Science.gov

Sample records for adipokinetic hormone akh

  1. Energy Homeostasis Control in Drosophila Adipokinetic Hormone Mutants.

    PubMed

    Gáliková, Martina; Diesner, Max; Klepsatel, Peter; Hehlert, Philip; Xu, Yanjun; Bickmeyer, Iris; Predel, Reinhard; Kühnlein, Ronald P

    2015-10-01

    Maintenance of biological functions under negative energy balance depends on mobilization of storage lipids and carbohydrates in animals. In mammals, glucagon and glucocorticoid signaling mobilizes energy reserves, whereas adipokinetic hormones (AKHs) play a homologous role in insects. Numerous studies based on AKH injections and correlative studies in a broad range of insect species established the view that AKH acts as master regulator of energy mobilization during development, reproduction, and stress. In contrast to AKH, the second peptide, which is processed from the Akh encoded prohormone [termed "adipokinetic hormone precursor-related peptide" (APRP)] is functionally orphan. APRP is discussed as ecdysiotropic hormone or as scaffold peptide during AKH prohormone processing. However, as in the case of AKH, final evidence for APRP functions requires genetic mutant analysis. Here we employed CRISPR/Cas9-mediated genome engineering to create AKH and AKH plus APRP-specific mutants in the model insect Drosophila melanogaster. Lack of APRP did not affect any of the tested steroid-dependent processes. Similarly, Drosophila AKH signaling is dispensable for ontogenesis, locomotion, oogenesis, and homeostasis of lipid or carbohydrate storage until up to the end of metamorphosis. During adulthood, however, AKH regulates body fat content and the hemolymph sugar level as well as nutritional and oxidative stress responses. Finally, we provide evidence for a negative autoregulatory loop in Akh gene regulation. PMID:26275422

  2. Energy Homeostasis Control in Drosophila Adipokinetic Hormone Mutants

    PubMed Central

    Gáliková, Martina; Diesner, Max; Klepsatel, Peter; Hehlert, Philip; Xu, Yanjun; Bickmeyer, Iris; Predel, Reinhard; Kühnlein, Ronald P.

    2015-01-01

    Maintenance of biological functions under negative energy balance depends on mobilization of storage lipids and carbohydrates in animals. In mammals, glucagon and glucocorticoid signaling mobilizes energy reserves, whereas adipokinetic hormones (AKHs) play a homologous role in insects. Numerous studies based on AKH injections and correlative studies in a broad range of insect species established the view that AKH acts as master regulator of energy mobilization during development, reproduction, and stress. In contrast to AKH, the second peptide, which is processed from the Akh encoded prohormone [termed “adipokinetic hormone precursor-related peptide” (APRP)] is functionally orphan. APRP is discussed as ecdysiotropic hormone or as scaffold peptide during AKH prohormone processing. However, as in the case of AKH, final evidence for APRP functions requires genetic mutant analysis. Here we employed CRISPR/Cas9-mediated genome engineering to create AKH and AKH plus APRP-specific mutants in the model insect Drosophila melanogaster. Lack of APRP did not affect any of the tested steroid-dependent processes. Similarly, Drosophila AKH signaling is dispensable for ontogenesis, locomotion, oogenesis, and homeostasis of lipid or carbohydrate storage until up to the end of metamorphosis. During adulthood, however, AKH regulates body fat content and the hemolymph sugar level as well as nutritional and oxidative stress responses. Finally, we provide evidence for a negative autoregulatory loop in Akh gene regulation. PMID:26275422

  3. New insights into adipokinetic hormone signaling.

    PubMed

    Vroemen, S F; Van der Horst, D J; Van Marrewijk, W J

    1998-06-25

    Flight activity of insects comprises one of the most intense biochemical processes known in nature, and therefore provides an attractive model system to study the hormonal regulation of metabolism during physical exercise. In long-distance flying insects, such as the migratory locust, both carbohydrate and lipid reserves are utilized as fuels for sustained flight activity. The mobilization of these energy stores in Locusta migratoria is mediated by three structurally related adipokinetic hormones (AKHs), which are all capable of stimulating the release of both carbohydrates and lipids from the fat body. To exert their effects intracellularly, these hormones induce a variety of signal transduction events, involving the activation of AKH receptors, GTP-binding proteins, cyclic AMP, inositol phosphates and Ca2+. In this review, we discuss recent advances in the research into AKH signaling. This not only includes the effects of the three AKHs on each of the signaling molecules, but also crosstalk between signaling cascades and the degradation rates of the hormones in the hemolymph. On the basis of the observed differences between the three AKHs, we have tried to construct a physiological model for their action in locusts, in order to answer a fundamental question in endocrinology: why do several structurally and functionally related peptide hormones co-exist in locusts (and animals in general), when apparently one single hormone would be sufficient to exert the desired effects? We suggest that the success of the migratory locust in performing long-distance flights is in part based on this neuropeptide multiplicity, with AKH-I being the strongest lipid-mobilizing hormone, AKH-II the most powerful carbohydrate mobilizer and AKH-III, a modulatory entity that predominantly serves to provide the animal with energy at rest. PMID:9723879

  4. Locust adipokinetic hormones mobilize diacylglycerols selectively.

    PubMed

    Tomcala, Ales; Bártů, Iva; Simek, Petr; Kodrík, Dalibor

    2010-05-01

    The diacylglycerols (DG) molecular species and their fatty acid (FA) composition were investigated by electrospray mass spectrometry (ESI-MS) and by gas chromatography with flame ionisation detection (GC-FID) in haemolymph of Locusta migratoria after application of adipokinetic hormones Locmi-AKH-I, -II and -III. The analyses showed (1) a heterogeneous distribution of individual DGs in haemolymph after the hormone application. The results revealed that mobilization of the DGs is molecular species-specific with the highest proportion of 34:1 DG (16:0/18:1 - mw 594Da) for all Locmi-AKHs bearing palmitic acid (C16:0) and oleic acid (C18:1) residues, and forming about 20% of the total mobilized DG content. (2) Analysis of fat body triacylglycerols revealed that all Locmi-AKHs mobilize the DGs selectively with the preference of those possessing the C18 and C16 FAs. The fat body FAs with carbon chain longer than 18 did not participate in the mobilization. (3) A distribution of FAs in the DG structures obtained by LC/ESI-MS, and FA analysis by GC-FID after transmethylation indicated a certain degree of Locmi-AKH selectivity toward the mobilized DGs and hence the FAs. The Locmi-AKH-I significantly prefers mobilization of DGs containing unsaturated FAs, while Locmi-AKH-II and -III prefer mobilization of saturated FAs. PMID:20139028

  5. The adipokinetic hormone family in Chrysomeloidea: structural and functional considerations *

    PubMed Central

    Gäde, Gerd; Marco, Heather G.

    2011-01-01

    Abstract The presented work is a hybrid of an overview and an original research paper on peptides belonging to the adipokinetic hormone (AKH) family that are present in the corpora cardiaca of Chrysomeloidea. First, we introduce the AKH/red pigment-concentrating hormone (RPCH) peptide family. Second, we collate the available primary sequence data on AKH peptides in Cerambycidae and Chrysomelidae, and we present new sequencing data (from previously unstudied species) obtained by liquid-chromatography coupled with ion trap electrospray ionisation mass spectrometry. Our expanded data set encompasses the primary structure of AKHs from seven species of Cerambycidae and three species of Chrysomelidae. All of these species synthesise the octapeptide code-named Peram-CAH-I (pGlu-Val-Asn-Phe-Ser-Pro-Asn-Trp amide). Whereas this is the sole AKH peptide in Cerambycidae, Chrysomelidae demonstrate a probable event of AKH gene duplication, thereby giving rise to an additional AKH. This second AKH peptide may be either Emppe-AKH (pGlu-Val-Asn-Phe-Thr-Pro-Asn-Trp amide) or Peram-CAH-II (pGlu-Leu-Thr-Phe-Thr-Pro-Asn-Trp amide). The peptide distribution and structural data suggest that both families are closely related and that Peram-CAH-I is the ancestral peptide. We hypothesise on the molecular evolution of Emppe-AKH and Peram-CAH-II from the ancestral peptide due to nonsynonymous missense single nucleotide polymorphism in the nucleotide coding sequence of prepro-AKH. Finally, we review the biological significance of the AKH peptides as hyperprolinaemic hormones in Chrysomeloidea, i.e. they cause an increase in the circulating concentration of proline. The mobilisation of proline has been demonstrated during flight in both cerambycid and chrysomelid beetles. PMID:22303105

  6. Structure-activity relationship of adipokinetic hormone analogs in the striped hawk moth, Hippotion eson.

    PubMed

    Marco, Heather G; Gäde, Gerd

    2015-06-01

    We showed previously that the sphingid moth Hippotion eson synthesizes the highest number of adipokinetic hormones (AKHs) ever recorded, viz. five, in its corpus cardiacum: two octa-, two nona- and one decapeptide. Further, the endogenous decapeptide (Manse-AKH-II) and the other four AKHs are all active in lipid mobilization, whereas a non-lepidopteran decapeptide (Lacsp-AKH, five amino acid substitutions compared with Manse-AKH-II), was inactive in H. eson. We tested the decapeptide, Lacol-AKH, from a noctuid moth for the first time in a bioassay and it shows a maximal AKH effect in H. eson. Lacol-AKH differs from Manse-AKH-II in three places and from Lacsp-AKH in four places. We, thus, used Lacol-AKH as a lead peptide on which a series of AKH analogs are based to represent: (a) single amino acid replacements (according to the substitutions in Lacsp-AKH), (b) shorter chain lengths, (c) modified termini, and (d) a replacement of Trp in position 8. These analogs, as well as a few naturally occurring AKHs from other lepidopterans were tested in in vivo adipokinetic assays to gain insight into the ligand-receptor interaction in H. eson. Our results show that the second and third amino acids are important for biological activity in the sphingid moth. Analogs with an N-[acetylated]Glu(1) (instead of a pyroGlu), or a free C-terminus, or Ala(8) were not active in the bioassays, while shortened Lacol-AKH analogs and the undecapeptide, non-amidated Vanca-AKH showed very reduced activity (below 25%). This information is important for the consideration of peptide mimetics to combat specific lepidopteran pest insects.

  7. Localization and Functional Characterization of a Novel Adipokinetic Hormone in the Mollusk, Aplysia californica

    PubMed Central

    Johnson, Joshua I.; Kavanaugh, Scott I.; Nguyen, Cindy; Tsai, Pei-San

    2014-01-01

    Increasing evidence suggests that gonadotropin-releasing hormone (GnRH), corazonin, adipokinetic hormone (AKH), and red pigment-concentrating hormone all share common ancestry to form a GnRH superfamily. Despite the wide presence of these peptides in protostomes, their biological effects remain poorly characterized in many taxa. This study had three goals. First, we cloned the full-length sequence of a novel AKH, termed Aplysia-AKH, and examined its distribution in an opisthobranch mollusk, Aplysia californica. Second, we investigated in vivo biological effects of Aplysia-AKH. Lastly, we compared the effects of Aplysia-AKH to a related A. californica peptide, Aplysia-GnRH. Results suggest that Aplysia-AKH mRNA and peptide are localized exclusively in central tissues, with abdominal, cerebral, and pleural ganglia being the primary sites of Aplysia-AKH production. However, Aplysia-AKH-positive fibers were found in all central ganglia, suggesting diverse neuromodulatory roles. Injections of A. californica with Aplysia-AKH significantly inhibited feeding, reduced body mass, increased excretion of feces, and reduced gonadal mass and oocyte diameter. The in vivo effects of Aplysia-AKH differed substantially from Aplysia-GnRH. Overall, the distribution and biological effects of Aplysia-AKH suggest it has diverged functionally from Aplysia-GnRH over the course of evolution. Further, that both Aplysia-AKH and Aplysia-GnRH failed to activate reproduction suggest the critical role of GnRH as a reproductive activator may be a phenomenon unique to vertebrates. PMID:25162698

  8. Characterization of the adipokinetic hormone receptor of the anautogenous flesh fly, Sarcophaga crassipalpis.

    PubMed

    Bil, Magdalena; Timmermans, Iris; Verlinden, Heleen; Huybrechts, Roger

    2016-06-01

    Adipokinetic hormone (AKH) is an insect neuropeptide mainly involved in fat body energy mobilization. In flies (Phormia regina, Sarcophaga crassipalpis), bugs (Pyrrhocoris apterus) and cockroaches (Periplaneta americana) AKH was also demonstrated to be involved in the regulation of digestion. This makes AKH an important peptide for anautogenous female flies that need to feed on a supplementary protein meal to initiate vitellogenesis, the large scale synthesis of yolk proteins and their uptake by the developing oocytes. Flesh fly AKH, originally identified as Phormia terraenovae hypertrehalosemic hormone (PhoteHrTH), functions through activation of the AKH receptor (AKHR). This is a G protein-coupled receptor that is the orthologue of the human gonadotropin-releasing hormone receptor. Pharmacological characterization indicated that the receptor can be activated by two related dipteran AKH ligands with an EC50 value in the low nanomolar range, whereas micromolar concentrations of the Tribolium castaneum AKH were needed. Consistent with the energy mobilizing function of AKH, the receptor transcript levels were most abundant in the fat body tissue. Nonetheless, Sarcophaga crassipalpis AKHR transcript levels were also high in the brain, the foregut and the hindgut. Interestingly, the receptor transcript numbers were reduced in almost all measured tissues after protein feeding. These changes may enforce the use of ingested energy carrying molecules prior to stored energy mobilization.

  9. Trehalose inhibits the release of adipokinetic hormones from the corpus cardiacum in the African migratory locust, Locusta migratoria, at the level of the adipokinetic cells.

    PubMed

    Passier, P C; Vullings, H G; Diederen, J H; Van der Horst, D J

    1997-05-01

    The effect of trehalose at various concentrations on the release of adipokinetic hormones (AKHs) from the adipokinetic cells in the glandular part of the corpus cardiacum of Locusta migratoria was studied in vitro. Pools of five corpora cardiaca or pools of five glandular parts of corpora cardiaca were incubated in a medium containing different concentrations of trehalose in the absence or presence of AKH-release-inducing agents. It was demonstrated that trehalose inhibits spontaneous release of AKH I in a dose-dependent manner. At a concentration of 80 mM, which is the concentration found in the hemolymph at rest, trehalose significantly decreased the release of AKH I induced by 100 microM locustatachykinin 1, 10 microM 3-isobutyl-1-methylxanthine (IBMX) or high potassium concentrations. The specificity of the effect of trehalose was studied by incubating pools of corpora cardiaca with the non-hydrolyzable disaccharide sucrose or with glucose, the degradation product of trehalose, both in the presence and absence of 10 microM IBMX. Sucrose had no effect at all on the release of AKH I, whereas glucose strongly inhibited its release. The results point to the inhibitory effect of trehalose on the release of AKH I being exerted, at least partly, at the level of the adipokinetic cells, possibly after its conversion into glucose. The data presented in this study support the hypothesis that in vivo the relatively high concentration of trehalose (80 mM) at rest strongly inhibits the release of AKHs. At the onset of flight, the demand for energy substrates exceeds the amount of trehalose that can be mobilized from the fat body and consequently the trehalose concentration in the hemolymph decreases. This relieves the inhibitory effect of trehalose on the release of AKHs, which in turn mobilize lipids from the fat body. PMID:9166120

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

    PubMed Central

    Li, Shizhong; Hauser, Frank; Skadborg, Signe K.; Nielsen, Stine V.; Kirketerp-Møller, Nikolaj; Grimmelikhuijzen, Cornelis J. P.

    2016-01-01

    Most multicellular animals belong to two evolutionary lineages, the Proto– and Deuterostomia, which diverged 640–760 million years (MYR) ago. Neuropeptide signaling is abundant in animals belonging to both lineages, but it is often unclear whether there exist evolutionary relationships between the neuropeptide systems used by proto- or deuterostomes. An exception, however, are members of the gonadotropin-releasing hormone (GnRH) receptor superfamily, which occur in both evolutionary lineages, where GnRHs are the ligands in Deuterostomia and GnRH-like peptides, adipokinetic hormone (AKH), corazonin, and AKH/corazonin-related peptide (ACP) are the ligands in Protostomia. AKH is a well-studied insect neuropeptide that mobilizes lipids and carbohydrates from the insect fat body during flight. In our present paper, we show that AKH is not only widespread in insects, but also in other Ecdysozoa and in Lophotrochozoa. Furthermore, we have cloned and deorphanized two G protein-coupled receptors (GPCRs) from the oyster Crassostrea gigas (Mollusca) that are activated by low nanomolar concentrations of oyster AKH (pQVSFSTNWGSamide). Our discovery of functional AKH receptors in molluscs is especially significant, because it traces the emergence of AKH signaling back to about 550 MYR ago and brings us closer to a more complete understanding of the evolutionary origins of the GnRH receptor superfamily. PMID:27628442

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

    PubMed

    Li, Shizhong; Hauser, Frank; Skadborg, Signe K; Nielsen, Stine V; Kirketerp-Møller, Nikolaj; Grimmelikhuijzen, Cornelis J P

    2016-01-01

    Most multicellular animals belong to two evolutionary lineages, the Proto- and Deuterostomia, which diverged 640-760 million years (MYR) ago. Neuropeptide signaling is abundant in animals belonging to both lineages, but it is often unclear whether there exist evolutionary relationships between the neuropeptide systems used by proto- or deuterostomes. An exception, however, are members of the gonadotropin-releasing hormone (GnRH) receptor superfamily, which occur in both evolutionary lineages, where GnRHs are the ligands in Deuterostomia and GnRH-like peptides, adipokinetic hormone (AKH), corazonin, and AKH/corazonin-related peptide (ACP) are the ligands in Protostomia. AKH is a well-studied insect neuropeptide that mobilizes lipids and carbohydrates from the insect fat body during flight. In our present paper, we show that AKH is not only widespread in insects, but also in other Ecdysozoa and in Lophotrochozoa. Furthermore, we have cloned and deorphanized two G protein-coupled receptors (GPCRs) from the oyster Crassostrea gigas (Mollusca) that are activated by low nanomolar concentrations of oyster AKH (pQVSFSTNWGSamide). Our discovery of functional AKH receptors in molluscs is especially significant, because it traces the emergence of AKH signaling back to about 550 MYR ago and brings us closer to a more complete understanding of the evolutionary origins of the GnRH receptor superfamily. PMID:27628442

  12. Locust adipokinetic hormones: carrier-independent transport and differential inactivation at physiological concentrations during rest and flight.

    PubMed Central

    Oudejans, R C; Vroemen, S F; Jansen, R F; Van der Horst, D J

    1996-01-01

    Since concomitant release of structurally related peptide hormones with apparently similar functions seems to be a general concept in endocrinology, we have studied the dynamics of the lifetime of the three known adipokinetic hormones (AKHs) of the migratory locust, which control flight-directed mobilization of carbohydrate and lipid from fat body stores. Although the structure of the first member of the AKHs has been known for 20 years, until now, reliable data on their inactivation and removal from the hemolymph are lacking, because measurement requires AKHs with high specific radioactivity. Employing tritiated AKHs with high specific radioactivity, obtained by catalytic reduction with tritium gas of the dehydroLeu2 analogues of the AKHs synthesized by the solid-phase procedure, studies with physiological doses of as low as 1.0 pmol per locust could be conducted. The AKHs appear to be transported in the hemolymph in their free forms and not associated with a carrier protein, despite their strong hydrophobicity. Application of AKHs in their free form in in vivo and in vitro studies therefore now has been justified. We have studied the degradation of the three AKHs during rest and flight. The first cleavage step by an endopeptidase is crucial, since the resulting degradation products lack any adipokinetic activity. Half-lives for AKH-I, -II and -III were 51, 40, and 5 min, respectively, for rest conditions and 35, 37, and 3 min, respectively, during flight. The rapid and differential degradation of structurally related hormones leads to changes in the ratio in which they are released and therefore will have important consequences for concerted hormone action at the level of the target organ or organs, suggesting that each of the known AKHs may play its own biological role in the overall syndrome of insect flight. PMID:8710926

  13. Effects of chronic administration of adipokinetic and hypertrehalosemic hormone on animal behavior, BDNF, and CREB expression in the hippocampus and neurogenesis in mice.

    PubMed

    Mutlu, Oguz; Gumuslu, Esen; Kokturk, Sibel; Ulak, Guner; Akar, Furuzan; Erden, Faruk; Kaya, Havva; Tanyeri, Pelin

    2016-02-01

    Neurosecretory cells in corpus cardiacum of insects synthesize a set of hormones that are called adipokinetic, hypertrehalosaemic or hyperprolinaemic, depending on insect in question. This study investigated effects of chronic administration of Anax imperator adipokinetic hormone (Ani-AKH), Libellula auripennis adipokinetic hormone (Lia-AKH), and Phormia-Terra hypertrehalosaemic hormone (Pht-HrTH) on depression, anxiety, analgesy, locomotion in forced swimming (FST), elevated plus-maze (EPM), hot plate, and locomotor activity tests. Ani-AKH (1 and 2 mg/kg), Lia-AKH (1 and 2 mg/kg), and Pht-HrTH (1 and 2 mg/kg) had antidepressant effects in forced swimming test. Lia-AKH (2 mg/kg) and Pht-HrTH (1 and 2 mg/kg) had anxiolytic effects when given chronically in elevated plus-maze test. Ani-AKH (1 and 2 mg/kg) and Pht-HrTH (2 mg/kg) had antinociceptive effects in hot plate test in male balb-c mice. Ani-AKH (2 mg/kg), Lia-AKH (1 and 2 mg/kg), and Pht-HrTH had locomotion-enhancing effects in locomotor activity test in male balb-c mice. Drug treatment significantly increased brain-derived neurotrophic factor (BDNF) and cyclic adenosine monophosphate (cAMP) response element binding protein (CREB) gene expression levels compared to control levels. Pht-HrTH and Ani-AKH groups had significantly increased numbers of BrdU-labeled cells, while neurodegeneration was lower in the Pht-HrTH group. Our study showed that AKH/RPCH family peptides may be used in treatment of psychiatric illness such as depression and anxiety, in treatment of pain and in diseases related to locomotion system. AKH/RPCH family peptides increase neurotrophic factors in brain and have potential proliferative and neuroprotective effects in hippocampal neurogenesis and neurodegeneration.

  14. Molecular characterization, tissue distribution, and ultrastructural localization of adipokinetic hormones in the CNS of the firebug Pyrrhocoris apterus (Heteroptera, Insecta).

    PubMed

    Kodrík, Dalibor; Stašková, Tereza; Jedličková, Veronika; Weyda, František; Závodská, Radka; Pflegerová, Jitka

    2015-01-01

    Adipokinetic hormones (AKHs) are a group of insect metabolic neurohormones, synthesized and released from an endocrine retrocerebral gland, the corpus cardiacum (CC). Small amounts of AKH have also been identified in the brain, although their role in this organ is not clear. To address this gap in the knowledge about insect brain biology, we studied the nucleotide sequence, tissue distribution, and subcellular localization of AKHs in the brain and CC of the firebug Pyrrhocoris apterus. This insect expresses two AKHs; the octapeptides Pyrap-AKH and Peram-CAH-II, the presence of which was documented in the both studied organs. In situ hybridization and quantitative reverse-transcription (q-RT)-PCR revealed the expression of the genes encoding for both AKHs not only in the CC, but also in brain. Electron microscopy analysis of the brain revealed the presence of these hormones in specialized secretory granules localized predominantly in the cellular bodies of neurons. The hormones might be transported from the granules into the axons, where they could play a role in neuronal signaling. Under acute stress induced by the injection of 3μmol KCl, the level of AKHs in the brain increased to a greater extent than that in the CC. These results might indicate an enhanced role of brain-derived AKHs in defence reaction under acute stress situations. PMID:25449136

  15. Role of adipokinetic hormone and adenosine in the anti-stress response in Drosophila melanogaster.

    PubMed

    Zemanová, Milada; Stašková, Tereza; Kodrík, Dalibor

    2016-01-01

    The role of adipokinetic hormone (AKH) and adenosine in the anti-stress response was studied in Drosophila melanogaster larvae and adults carrying a mutation in the Akh gene (Akh(1)), the adenosine receptor gene (AdoR(1)), or in both of these genes (Akh(1) AdoR(1) double mutant). Stress was induced by starvation or by the addition of an oxidative stressor paraquat (PQ) to food. Mortality tests revealed that the Akh(1) mutant was the most resistant to starvation, while the AdoR(1) mutant was the most sensitive. Conversely, the Akh(1) AdoR(1) double mutant was more sensitive to PQ toxicity than either of the single mutants. Administration of PQ significantly increased the Drome-AKH level in w(1118) and AdoR(1) larvae; however, this was not accompanied by a simultaneous increase in Akh gene expression. In contrast, PQ significantly increased the expression of the glutathione S-transferase D1 (GstD1) gene. The presence of both a functional adenosine receptor and AKH seem to be important for the proper control of GstD1 gene expression under oxidative stress, however, the latter appears to play more dominant role. On the other hand, differences in glutathione S-transferase (GST) activity among the strains, and between untreated and PQ-treated groups were minimal. In addition, the glutathione level was significantly lower in all untreated AKH- or AdoR-deficient mutant flies as compared with the untreated control w(1118) flies and further declined following treatment with PQ. All oxidative stress characteristics modified by mutations in Akh gene were restored or even improved by 'rescue' mutation in flies which ectopically express Akh. Thus, the results of the present study demonstrate the important roles of AKH and adenosine in the anti-stress response elicited by PQ in a D. melanogaster model, and provide the first evidence for the involvement of adenosine in the anti-oxidative stress response in insects. PMID:27374982

  16. The proprotein convertase encoded by amontillado (amon) is required in Drosophila corpora cardiaca endocrine cells producing the glucose regulatory hormone AKH.

    PubMed

    Rhea, Jeanne M; Wegener, Christian; Bender, Michael

    2010-05-01

    Peptide hormones are potent signaling molecules that coordinate animal physiology, behavior, and development. A key step in activation of these peptide signals is their proteolytic processing from propeptide precursors by a family of proteases, the subtilisin-like proprotein convertases (PCs). Here, we report the functional dissection of amontillado (amon), which encodes the Drosophila homolog of the mammalian PC2 protein, using cell-type specific inactivation and rescue experiments, and we show that amon is required in the islet-like adipokinetic hormone (AKH)-producing cells that regulate sugar homeostasis. In Drosophila, AKH acts analogously to vertebrate glucagon to increase circulating sugar levels from energy stores, while insulin-like peptides (DILPs) act to decrease sugar levels. amon mutant larvae have significantly reduced hemolymph sugar levels, and thus phenocopy larvae where the AKH-producing cells in the corpora cardiaca have been ablated. Reduction of amon expression in these cells via cell-specific RNA inactivation also results in larvae with reduced sugar levels while expression of amon in AKH cells in an amon mutant background rescues hypoglycemia. Hypoglycemia in larvae resulting from amon RNA inactivation in the AKH cells can be rescued by global expression of the akh gene. Finally, mass spectrometric profiling shows that the production of mature AKH is inhibited in amon mutants. Our data indicate that amon function in the AKH cells is necessary to maintain normal sugar homeostasis, that amon functions upstream of akh, and that loss of mature AKH is correlated with loss of amon activity. These observations indicate that the AKH propeptide is a proteolytic target of the amon proprotein convertase and provide evidence for a conserved role of PC2 in processing metabolic peptide hormones. PMID:20523747

  17. The Proprotein Convertase Encoded by amontillado (amon) Is Required in Drosophila Corpora Cardiaca Endocrine Cells Producing the Glucose Regulatory Hormone AKH

    PubMed Central

    Rhea, Jeanne M.; Wegener, Christian; Bender, Michael

    2010-01-01

    Peptide hormones are potent signaling molecules that coordinate animal physiology, behavior, and development. A key step in activation of these peptide signals is their proteolytic processing from propeptide precursors by a family of proteases, the subtilisin-like proprotein convertases (PCs). Here, we report the functional dissection of amontillado (amon), which encodes the Drosophila homolog of the mammalian PC2 protein, using cell-type specific inactivation and rescue experiments, and we show that amon is required in the islet-like adipokinetic hormone (AKH)–producing cells that regulate sugar homeostasis. In Drosophila, AKH acts analogously to vertebrate glucagon to increase circulating sugar levels from energy stores, while insulin-like peptides (DILPs) act to decrease sugar levels. amon mutant larvae have significantly reduced hemolymph sugar levels, and thus phenocopy larvae where the AKH–producing cells in the corpora cardiaca have been ablated. Reduction of amon expression in these cells via cell-specific RNA inactivation also results in larvae with reduced sugar levels while expression of amon in AKH cells in an amon mutant background rescues hypoglycemia. Hypoglycemia in larvae resulting from amon RNA inactivation in the AKH cells can be rescued by global expression of the akh gene. Finally, mass spectrometric profiling shows that the production of mature AKH is inhibited in amon mutants. Our data indicate that amon function in the AKH cells is necessary to maintain normal sugar homeostasis, that amon functions upstream of akh, and that loss of mature AKH is correlated with loss of amon activity. These observations indicate that the AKH propeptide is a proteolytic target of the amon proprotein convertase and provide evidence for a conserved role of PC2 in processing metabolic peptide hormones. PMID:20523747

  18. Two novel tyrosine-containing peptides (Tyr(4)) of the adipokinetic hormone family in beetles of the families Coccinellidae and Silphidae.

    PubMed

    Gäde, Gerd; Šimek, Petr; Marco, Heather G

    2015-11-01

    Novel members of the adipokinetic hormone family of peptides have been identified from the corpora cardiaca (CC) of two species of beetles representing two families, the Silphidae and the Coccinellidae. A crude CC extract (0.3 gland equivalents) of the burying beetle, Nicrophorus vespilloides, was active in mobilizing trehalose in a heterologous assay using the cockroach Periplaneta americana, whereas the CC extract (0.5 gland equivalents) of the ladybird beetle, Harmonia axyridis, exhibited no hypertrehalosemic activity. Primary sequences of one adipokinetic hormone from each species were elucidated by liquid chromatography coupled to electrospray mass spectrometry (LC-MS). The multiple MS(N) electrospray mass data revealed an octapeptide with an unusual tyrosine residue at position 4 for each species: pGlu-Leu-Thr-Tyr-Ser-Thr-Gly-Trp amide for N. vespilloides (code-named Nicve-AKH) and pGlu-Ile-Asn-Tyr-Ser-Thr-Gly-Trp amide for H. axyridis (code-named Harax-AKH). Assignment of the correct sequences was confirmed by synthesis of the peptides and co-elution in reversed-phase high-performance liquid chromatography with fluorescence detection or by LC-MS. Moreover, synthetic peptides were shown to be active in the heterologous cockroach assay system, but Harax-AKH only at a dose of 30 pmol, which explains the negative result with the crude CC extract. It appears that the tyrosine residue at position 4 can be used as a diagnostic feature for certain beetle adipokinetic peptides, because this feature has not been found in another order other than Coleoptera. PMID:26031827

  19. Two novel tyrosine-containing peptides (Tyr(4)) of the adipokinetic hormone family in beetles of the families Coccinellidae and Silphidae.

    PubMed

    Gäde, Gerd; Šimek, Petr; Marco, Heather G

    2015-11-01

    Novel members of the adipokinetic hormone family of peptides have been identified from the corpora cardiaca (CC) of two species of beetles representing two families, the Silphidae and the Coccinellidae. A crude CC extract (0.3 gland equivalents) of the burying beetle, Nicrophorus vespilloides, was active in mobilizing trehalose in a heterologous assay using the cockroach Periplaneta americana, whereas the CC extract (0.5 gland equivalents) of the ladybird beetle, Harmonia axyridis, exhibited no hypertrehalosemic activity. Primary sequences of one adipokinetic hormone from each species were elucidated by liquid chromatography coupled to electrospray mass spectrometry (LC-MS). The multiple MS(N) electrospray mass data revealed an octapeptide with an unusual tyrosine residue at position 4 for each species: pGlu-Leu-Thr-Tyr-Ser-Thr-Gly-Trp amide for N. vespilloides (code-named Nicve-AKH) and pGlu-Ile-Asn-Tyr-Ser-Thr-Gly-Trp amide for H. axyridis (code-named Harax-AKH). Assignment of the correct sequences was confirmed by synthesis of the peptides and co-elution in reversed-phase high-performance liquid chromatography with fluorescence detection or by LC-MS. Moreover, synthetic peptides were shown to be active in the heterologous cockroach assay system, but Harax-AKH only at a dose of 30 pmol, which explains the negative result with the crude CC extract. It appears that the tyrosine residue at position 4 can be used as a diagnostic feature for certain beetle adipokinetic peptides, because this feature has not been found in another order other than Coleoptera.

  20. A unique charged tyrosine-containing member of the adipokinetic hormone/red-pigment-concentrating hormone peptide family isolated and sequenced from two beetle species.

    PubMed

    Gäde, G

    1991-05-01

    An identical neuropeptide was isolated from the corpora cardiaca of two beetle species, Melolontha melolontha and Geotrupes stercorosus. Its primary structure was determined by pulsed-liquid-phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal pyroglutamate residue. The C-terminus was also blocked, as indicated by the lack of digestion when the peptide was incubated with carboxypeptidase A. The sequence of this peptide, which is designated Mem-CC, is pGlu-Leu-Asn-Tyr-Ser-Pro-Asp-Trp-NH2. It is a new member of the adipokinetic hormone/red-pigment-concentrating hormone (AKH/RPCH) family of peptides with two unusual structural features: it is charged and contains a tyrosine residue at position 4, where all other family members have a phenylalanine residue. Structure-activity studies in the migratory locust (Locusta migratoria) and the American cockroach (Periplaneta americana) revealed that the peptide was poorly active, owing to its structural uniqueness. PMID:2039445

  1. Unique translational modification of an invertebrate neuropeptide: a phosphorylated member of the adipokinetic hormone peptide family

    PubMed Central

    2005-01-01

    Separation of an extract of corpora cardiaca from the protea beetle, Trichostetha fascicularis, by single-step RP (reverse-phase)-HPLC and monitoring of tryptophan fluorescence resulted in two distinctive peaks, the material of which mobilized proline and carbohydrates in a bioassay performed using the beetle. Material from one of these peaks was; however, inactive in the classical bioassays of locusts and cockroaches that are used for detecting peptides belonging to the AKH (adipokinetic hormone) family. After enzymatically deblocking the N-terminal pyroglutamic acid (pGlu) residue in the peptide material and sequencing by Edman degradation, a partial sequence was obtained: (pGlu)-Ile-Asn-Met-Thr-Xaa-Gly-Trp. The complete sequence was deduced from ESI-MSn (electrospray ionization multi-stage-MS); position six was identified as a phosphothreonine residue and the C-terminus is amidated. The peptide, code-named Trifa-CC, was chemically synthesized and used in confirmatory experiments to show that the primary structure had been correctly assigned. To our knowledge, this is the first report of a phosphorylated invertebrate neuropeptide. Synthetic Trifa-CC co-elutes with the natural peptide, found in the gland of the protea beetle, after RP-HPLC. Moreover, the natural peptide can be dephosphorylated by alkaline phosphatase and the product of that reaction has the same retention time as a synthetic nonphosphorylated octapeptide which has the same sequence as Trifa-CC. Finally, synthetic Trifa-CC has hypertrehalosaemic and hyperprolinaemic biological activity in the protea beetle, but even high concentrations of synthetic Trifa-CC are inactive in locusts and cockroaches. Hence, the correct peptide structure has been assigned. Trifa-CC of the protea beetle is an unusual member of the AKH family that is unique in its post-translational modification. Since it increases the concentration of carbohydrates and proline in the haemolymph when injected into the protea beetle, and

  2. The adipokinetic neuropeptide of Mantodea. Sequence elucidation and evolutionary relationships.

    PubMed

    Gäde, G

    1991-03-01

    A neuropeptide with adipokinetic activity in Locusta migratoria and the mantid Empusa pennata, and hypertrehalosaemic activity in Periplaneta americana, was isolated by reversed-phase high performance liquid chromatography from corpora cardiaca of the mantids E. pennata and Sphodromantis sp. After brief enzymatic digestion by 5-oxoprolylpeptidase the primary structure of the peptide of each species was determined by pulsed-liquid phase sequencing employing Edman degradation. The C-terminus of both peptides was blocked, as indicated by the lack of digestion with carboxypeptidase A. The peptides of both species were identical: a blocked, uncharged octapeptide with the sequence L-Glu-Val-Asn-Phe-Thr-Pro-Asn-Trp-NH2. The peptide is now called mantid adipokinetic hormone (Emp-AKH). The synthetic peptide was chromatographically indistinguishable from the natural compound and increased blood lipids in locusts and blood carbohydrates in cockroaches when administered in low doses. The structural features clearly define the peptide as a novel member of the large AKH/RPCH-family of peptides. Seven amino-acid residues are at identical positions in Emp-AKH when compared with the adipokinetic hormone of a dragonfly (Lia-AKH) and the hypertrehalosaemic hormone I from the American cockroach (Pea-CAH-I). Evolutionary relationships to other insect orders are discussed.

  3. Identification of distinct c-terminal domains of the Bombyx adipokinetic hormone receptor that are essential for receptor export, phosphorylation and internalization.

    PubMed

    Huang, Haishan; Deng, Xiaoyan; He, Xiaobai; Yang, Wen; Li, Guo; Shi, Ying; Shi, Liangen; Mei, Lijuan; Gao, Jimin; Zhou, Naiming

    2011-09-01

    Neuropeptides of the adipokinetic hormone (AKH) family play important roles in insect hemolymph sugar homeostasis, larval lipolysis and storage-fat mobilization. Our previous studies have shown that the adipokinetic hormone receptor (AKHR), a Gs-coupled receptor, induces intracellular cAMP accumulation, calcium mobilization and ERK1/2 phosphorylation upon agonist stimulation. However, the underlying molecular mechanisms that regulate the internalization and desensitization of AKHR remain largely unknown. In the current study we made a construct to express AKHR fused with enhanced green fluorescent protein (EGFP) at its C-terminal end to further characterize AKHR internalization. In stable AKHR-EGFP-expressing HEK-293 cells, AKHR-EGFP was mainly localized at the plasma membrane and was rapidly internalized in a dose- and time-dependent manner via the clathrin-coated pit pathway upon agonist stimulation, and internalized receptors were slowly recovered to the cell surface after the removal of AKH peptides. The results derived from RNA interference and arrestin translocation demonstrated that G protein-coupled receptor kinase 2 and 5 (GRK2/5) and β-arrestin2 were involved in receptor phosphorylation and internalization. Furthermore, experiments using deletion and site-directed mutagenesis strategies identified the three residues (Thr356, Ser359 and Thr362) responsible for GRK-mediated phosphorylation and internalization and the C-terminal domain from residue-322 to residue-342 responsible for receptor export from ER. This is the first detailed investigation of the internalization and trafficking of insect G protein-coupled receptors.

  4. Isolation and structure of a novel charged member of the red-pigment-concentrating hormone-adipokinetic hormone family of peptides isolated from the corpora cardiaca of the blowfly Phormia terraenovae (Diptera).

    PubMed

    Gäde, G; Wilps, H; Kellner, R

    1990-07-15

    A hypertrehalosaemic neuropeptide from the corpora cardiaca of the blowfly Phormia terraenovae has been isolated by reversed-phase h.p.l.c., and its primary structure was determined by pulsed-liquid phase sequencing employing Edman chemistry after enzymically deblocking the N-terminal pyroglutamate residue. The C-terminus was also blocked, as indicated by the lack of digestion when the peptide was incubated with carboxypeptidase A. The octapeptide has the sequence pGlu-Leu-Thr-Phe-Ser-Pro-Asp-Trp-NH2 and is clearly defined as a novel member of the RPCH/AKH (red-pigment-concentrating hormone/adipokinetic hormone) family of peptides. It is the first charged member of this family to be found. The synthetic peptide causes an increase in the haemolymph carbohydrate concentration in a dose-dependent fashion in blowflies and therefore is named 'Phormia terraenovae hypertrehalosaemic hormone' (Pht-HrTH). In addition, receptors in the fat-body of the American cockroach (Periplaneta americana) recognize the peptide, resulting in carbohydrate elevation in the blood. However, fat-body receptors of the migratory locust (Locusta migratoria) do not recognize this charged molecule, and thus no lipid mobilization is observed in this species. PMID:2386478

  5. Water sensor ppk28 modulates Drosophila lifespan and physiology through AKH signaling

    PubMed Central

    Waterson, Michael J.; Chung, Brian Y.; Harvanek, Zachary M.; Ostojic, Ivan; Alcedo, Joy; Pletcher, Scott D.

    2014-01-01

    Sensory perception modulates lifespan across taxa, presumably due to alterations in physiological homeostasis after central nervous system integration. The coordinating circuitry of this control, however, remains unknown. Here, we used the Drosophila melanogaster gustatory system to dissect one component of sensory regulation of aging. We found that loss of the critical water sensor, pickpocket 28 (ppk28), altered metabolic homeostasis to promote internal lipid and water stores and extended healthy lifespan. Additionally, loss of ppk28 increased neuronal glucagon-like adipokinetic hormone (AKH) signaling, and the AKH receptor was necessary for ppk28 mutant effects. Furthermore, activation of AKH-producing cells alone was sufficient to enhance longevity, suggesting that a perceived lack of water availability triggers a metabolic shift that promotes the production of metabolic water and increases lifespan via AKH signaling. This work provides an example of how discrete gustatory signals recruit nutrient-dependent endocrine systems to coordinate metabolic homeostasis, thereby influencing long-term health and aging. PMID:24821805

  6. Dietary sugar promotes systemic TOR activation in Drosophila through AKH-dependent selective secretion of Dilp3

    PubMed Central

    Kim, Jung; Neufeld, Thomas P.

    2015-01-01

    Secreted ligands of the insulin family promote cell growth and maintain sugar homeostasis. Insulin release is tightly regulated in response to dietary conditions, but how insulin producing cells (IPCs) coordinate their responses to distinct nutrient signals is unclear. Here, we show that regulation of insulin secretion in Drosophila larvae has been segregated into distinct branches: whereas amino acids promote secretion of Drosophila insulin-like peptide 2 (Dilp2), circulating sugars promote selective release of Dilp3. Dilp3 is uniquely required for sugar-mediated activation of TOR signaling and suppression of autophagy in the larval fat body. Sugar levels are not sensed directly by the IPCs, but rather by the adipokinetic hormone (AKH)-producing cells of the corpora cardiaca, and we demonstrate that AKH signaling is required in the IPCs for sugar-dependent Dilp3 release. Thus, IPCs integrate multiple cues to regulate secretion of distinct insulin subtypes under varying nutrient conditions. PMID:25882208

  7. Water scorpions (Heteroptera, Nepidae) and giant water bugs (Heteroptera, Belostomatidae): sources of new members of the adipokinetic hormone/red pigment-concentrating hormone family.

    PubMed

    Gäde, Gerd; Simek, Petr; Marco, Heather G

    2007-07-01

    Two novel octapeptide members of the AKH/RPCH family have been identified from the corpora cardiaca (CC) of two species of water bugs. The giant water bug Lethocerus indicus (family: Belostomatidae) contains a peptide code-named Letin-AKH with the sequence pGlu-Val-Asn-Phe-Ser-Pro-Tyr-Trp amide, and the water scorpion Nepa cinerea (family: Nepidae) has the peptide code-named Nepci-AKH with the sequence pGlu-Leu/Ile-Asn-Phe-Ser-Ser-Gly-Trp amide. The sequences were deduced from the multiple MS(N) electrospray mass data from crude CC extracts. Synthetic peptides were made and co-elution on reversed-phase high performance liquid chromatography (RP-HPLC) with the natural peptide from crude gland extract confirmed the accuracy of the deduced sequence for Letin-AKH and demonstrated that Nepci-AKH contains a Leu residue at position 2 and not an Ile residue. A previously characterized member of the AKH/RPCH family was identified in the stick water scorpion Ranatra linearis by mass spectrometry: Grybi-AKH (pGlu-Val-Asn-Phe-Ser-Thr-Gly-Trp amide) has the same mass (919 Da) as Nepci-AKH and differs in two positions from Nepci-AKH (residues 2 and 6). The apparent function of the peptides is to achieve lipid mobilization in the species under investigation; indications for this came from conspecific bioassays using the appropriate synthetic peptides for injecting into the insects. This function is very likely linked to dispersal flight metabolism of water bugs. Swimming activity in N. cinerea also results in an increase in lipid concentration in the hemolymph.

  8. Hormonal enhancement of insecticide efficacy in Tribolium castaneum: oxidative stress and metabolic aspects.

    PubMed

    Plavšin, Ivana; Stašková, Tereza; Šerý, Michal; Smýkal, Vlastimil; Hackenberger, Branimir K; Kodrík, Dalibor

    2015-04-01

    Insect anti-stress responses, including those induced by insecticides, are controlled by adipokinetic hormones (AKHs). We examined the physiological consequences of Pyrap-AKH application on Tribolium castaneum adults (AKH-normal and AKH-deficient prepared by the RNAi technique) treated by two insecticides, pirimiphos-methyl and deltamethrin. Co-application of pirimiphos-methyl and/or deltamethrin with AKH significantly increased beetle mortality compared with application of the insecticides alone. This co-treatment was accompanied by substantial stimulation of general metabolism, as monitored by carbon dioxide production. Further, the insecticide treatment alone affected some basic markers of oxidative stress: it lowered total antioxidative capacity as well as the activity of superoxide dismutase in the beetle body; in addition, it enhanced the activity of catalase and glutathione-S-transferase. However, these discrepancies in oxidative stress markers were eliminated/reduced by co-application with Pyrap-AKH. We suggest that the elevation of metabolism, which is probably accompanied with faster turnover of toxins, might be responsible for the higher mortality that results after AKH and insecticide co-application. Changes in oxidative stress markers are probably not included in the mechanisms responsible for increased mortality.

  9. Hormonal Regulation of Response to Oxidative Stress in Insects-An Update.

    PubMed

    Kodrík, Dalibor; Bednářová, Andrea; Zemanová, Milada; Krishnan, Natraj

    2015-01-01

    Insects, like other organisms, must deal with a wide variety of potentially challenging environmental factors during the course of their life. An important example of such a challenge is the phenomenon of oxidative stress. This review summarizes the current knowledge on the role of adipokinetic hormones (AKH) as principal stress responsive hormones in insects involved in activation of anti-oxidative stress response pathways. Emphasis is placed on an analysis of oxidative stress experimentally induced by various stressors and monitored by suitable biomarkers, and on detailed characterization of AKH's role in the anti-stress reactions. These reactions are characterized by a significant increase of AKH levels in the insect body, and by effective reversal of the markers-disturbed by the stressors-after co-application of the stressor with AKH. A plausible mechanism of AKH action in the anti-oxidative stress response is discussed as well: this probably involves simultaneous employment of both protein kinase C and cyclic adenosine 3',5'-monophosphate pathways in the presence of extra and intra-cellular Ca(2+) stores, with the possible involvement of the FoxO transcription factors. The role of other insect hormones in the anti-oxidative defense reactions is also discussed. PMID:26516847

  10. Hormonal Regulation of Response to Oxidative Stress in Insects-An Update.

    PubMed

    Kodrík, Dalibor; Bednářová, Andrea; Zemanová, Milada; Krishnan, Natraj

    2015-10-27

    Insects, like other organisms, must deal with a wide variety of potentially challenging environmental factors during the course of their life. An important example of such a challenge is the phenomenon of oxidative stress. This review summarizes the current knowledge on the role of adipokinetic hormones (AKH) as principal stress responsive hormones in insects involved in activation of anti-oxidative stress response pathways. Emphasis is placed on an analysis of oxidative stress experimentally induced by various stressors and monitored by suitable biomarkers, and on detailed characterization of AKH's role in the anti-stress reactions. These reactions are characterized by a significant increase of AKH levels in the insect body, and by effective reversal of the markers-disturbed by the stressors-after co-application of the stressor with AKH. A plausible mechanism of AKH action in the anti-oxidative stress response is discussed as well: this probably involves simultaneous employment of both protein kinase C and cyclic adenosine 3',5'-monophosphate pathways in the presence of extra and intra-cellular Ca(2+) stores, with the possible involvement of the FoxO transcription factors. The role of other insect hormones in the anti-oxidative defense reactions is also discussed.

  11. Hormonal Regulation of Response to Oxidative Stress in Insects—An Update

    PubMed Central

    Kodrík, Dalibor; Bednářová, Andrea; Zemanová, Milada; Krishnan, Natraj

    2015-01-01

    Insects, like other organisms, must deal with a wide variety of potentially challenging environmental factors during the course of their life. An important example of such a challenge is the phenomenon of oxidative stress. This review summarizes the current knowledge on the role of adipokinetic hormones (AKH) as principal stress responsive hormones in insects involved in activation of anti-oxidative stress response pathways. Emphasis is placed on an analysis of oxidative stress experimentally induced by various stressors and monitored by suitable biomarkers, and on detailed characterization of AKH’s role in the anti-stress reactions. These reactions are characterized by a significant increase of AKH levels in the insect body, and by effective reversal of the markers—disturbed by the stressors—after co-application of the stressor with AKH. A plausible mechanism of AKH action in the anti-oxidative stress response is discussed as well: this probably involves simultaneous employment of both protein kinase C and cyclic adenosine 3′,5′-monophosphate pathways in the presence of extra and intra-cellular Ca2+ stores, with the possible involvement of the FoxO transcription factors. The role of other insect hormones in the anti-oxidative defense reactions is also discussed. PMID:26516847

  12. Sequence analyses of two neuropeptides of the AKH/RPCH-family from the lubber grasshopper, Romalea microptera.

    PubMed

    Gäde, G; Hilbich, C; Beyreuther, K; Rinehart, K L

    1988-01-01

    Two neuropeptides with adipokinetic activity in Locusta migratoria and hypertrehalosaemic activity in Periplaneta americana were purified by high-performance liquid chromatography from the corpus cardiacum of the lubber grasshopper, Romalea microptera. The sequences of both peptides, designated Ro I and Ro II, were determined by gas-phase sequencing employing Edman degradation after the N-terminal pyroglutamate residue was enzymatically deblocked, as well as by fast atom bombardment mass spectrometry. Ro I was found to be a decapeptide with the primary structure: pGlu-Val-Asn-Phe-Thr-Pro-Asn-Trp-Gly-Thr-NH2, whereas Ro II is an octapeptide with the structure: pGlu-Val-Asn-Phe-Ser-Thr-Gly-Trp-NH2. Ro II is identical with AKH-G isolated from the cricket Gryllus bimaculatus. Synthetic materials having the assigned structures were found to be chromatographically, mass spectrometrically, and biologically indistinguishable from the natural peptides, confirming the sequences and establishing the Romalea peptides as members of the AKH/RPCH-family of peptides. PMID:3226948

  13. Nosema ceranae alters a highly conserved hormonal stress pathway in honeybees.

    PubMed

    Mayack, C; Natsopoulou, M E; McMahon, D P

    2015-12-01

    Nosema ceranae, an emerging pathogen of the western honeybee (Apis mellifera), is implicated in recent pollinator losses and causes severe energetic stress. However, whether precocious foraging and accelerated behavioural maturation in infected bees are caused by the infection itself or via indirect energetic stress remains unknown. Using a combination of nutritional and infection treatments, we investigated how starvation and infection alters the regulation of adipokinetic hormone (AKH) and octopamine, two highly conserved physiological pathways that respond to energetic stress by mobilizing fat stores and increasing search activity for food. Although there was no response from AKH when bees were experimentally infected with N. ceranae or starved, supporting the notion that honeybees have lost this pathway, there were significant regulatory changes in the octopamine pathway. Significantly, we found no evidence of acute energetic stress being the only cause of symptoms associated with N. ceranae infection. Therefore, the parasite itself appears to alter regulatory components along a highly conserved physiological pathway in an infection-specific manner. This indicates that pathogen-induced behavioural alteration of chronically infected bees should not just be viewed as a coincidental short-term by-product of pathogenesis (acute energetic stress) and may be a result of a generalist manipulation strategy to obtain energy for reproduction.

  14. Nosema ceranae alters a highly conserved hormonal stress pathway in honeybees.

    PubMed

    Mayack, C; Natsopoulou, M E; McMahon, D P

    2015-12-01

    Nosema ceranae, an emerging pathogen of the western honeybee (Apis mellifera), is implicated in recent pollinator losses and causes severe energetic stress. However, whether precocious foraging and accelerated behavioural maturation in infected bees are caused by the infection itself or via indirect energetic stress remains unknown. Using a combination of nutritional and infection treatments, we investigated how starvation and infection alters the regulation of adipokinetic hormone (AKH) and octopamine, two highly conserved physiological pathways that respond to energetic stress by mobilizing fat stores and increasing search activity for food. Although there was no response from AKH when bees were experimentally infected with N. ceranae or starved, supporting the notion that honeybees have lost this pathway, there were significant regulatory changes in the octopamine pathway. Significantly, we found no evidence of acute energetic stress being the only cause of symptoms associated with N. ceranae infection. Therefore, the parasite itself appears to alter regulatory components along a highly conserved physiological pathway in an infection-specific manner. This indicates that pathogen-induced behavioural alteration of chronically infected bees should not just be viewed as a coincidental short-term by-product of pathogenesis (acute energetic stress) and may be a result of a generalist manipulation strategy to obtain energy for reproduction. PMID:26335565

  15. Locust flight activity as a model for hormonal regulation of lipid mobilization and transport.

    PubMed

    Van der Horst, Dick J; Rodenburg, Kees W

    2010-08-01

    Flight activity of insects provides a fascinating yet relatively simple model system for studying the regulation of processes involved in energy metabolism. This is particularly highlighted during long-distance flight, for which the locust constitutes a long-standing favored model insect, which as one of the most infamous agricultural pests additionally has considerable economical importance. Remarkably many aspects and processes pivotal to our understanding of (neuro)hormonal regulation of lipid mobilization and transport during insect flight activity have been discovered in the locust; among which are the peptide adipokinetic hormones (AKHs), synthesized and stored by the neurosecretory cells of the corpus cardiacum, that regulate and integrate lipid (diacylglycerol) mobilization and transport, the functioning of the reversible conversions of lipoproteins (lipophorins) in the hemolymph during flight activity, revealing novel concepts for the transport of lipids in the circulatory system, and the structure and functioning of the exchangeable apolipopotein, apolipophorin III, which exhibits a dual capacity to exist in both lipid-bound and lipid-free states that is essential to these lipophorin conversions. Besides, the lipophorin receptor (LpR) was identified and characterized in the locust. In an integrative approach, this short review aims at highlighting the locust as an unrivalled model for studying (neuro)hormonal regulation of lipid mobilization and transport during insect flight activity, that additionally has offered a broad and profound research model for integrative physiology and biochemistry, and particularly focuses on recent developments in the concept of AKH-induced changes in the lipophorin system during locust flight, that deviates fundamentally from the lipoprotein-based transport of lipids in the circulation of mammals. Current studies in this field employing the locust as a model continue to attribute to its role as a favored model organism, but

  16. Gustatory perception and fat body energy metabolism are jointly affected by vitellogenin and juvenile hormone in honey bees.

    PubMed

    Wang, Ying; Brent, Colin S; Fennern, Erin; Amdam, Gro V

    2012-06-01

    Honey bees (Apis mellifera) provide a system for studying social and food-related behavior. A caste of workers performs age-related tasks: young bees (nurses) usually feed the brood and other adult bees inside the nest, while older bees (foragers) forage outside for pollen, a protein/lipid source, or nectar, a carbohydrate source. The workers' transition from nursing to foraging and their foraging preferences correlate with differences in gustatory perception, metabolic gene expression, and endocrine physiology including the endocrine factors vitellogenin (Vg) and juvenile hormone (JH). However, the understanding of connections among social behavior, energy metabolism, and endocrine factors is incomplete. We used RNA interference (RNAi) to perturb the gene network of Vg and JH to learn more about these connections through effects on gustation, gene transcripts, and physiology. The RNAi perturbation was achieved by single and double knockdown of the genes ultraspiracle (usp) and vg, which encode a putative JH receptor and Vg, respectively. The double knockdown enhanced gustatory perception and elevated hemolymph glucose, trehalose, and JH. We also observed transcriptional responses in insulin like peptide 1 (ilp1), the adipokinetic hormone receptor (AKHR), and cGMP-dependent protein kinase (PKG, or "foraging gene" Amfor). Our study demonstrates that the Vg-JH regulatory module controls changes in carbohydrate metabolism, but not lipid metabolism, when worker bees shift from nursing to foraging. The module is also placed upstream of ilp1, AKHR, and PKG for the first time. As insulin, adipokinetic hormone (AKH), and PKG pathways influence metabolism and gustation in many animals, we propose that honey bees have conserved pathways in carbohydrate metabolism and conserved connections between energy metabolism and gustatory perception. Thus, perhaps the bee can make general contributions to the understanding of food-related behavior and metabolic disorders.

  17. Induced hyperlipaemia and immune challenge in locusts.

    PubMed

    Mullen, Lisa M; Lightfoot, Mary E; Goldsworthy, Graham J

    2004-05-01

    Injections of immunogens, such as beta-1,3-glucan or lipopolysaccharide (LPS), bring about a marked hyperlipaemia with associated changes in lipophorins and apolipophorin-III in the haemolymph of Locusta migratoria. These changes are similar to those observed after injection of adipokinetic hormone (AKH). The possibility that endogenous AKH is released as part of the response to these immunogens is investigated using passive immunisation against AKH-I, and measurement of AKH-I titre in the haemolymph after injection of immunogens. The data presented show that, despite the similarity of the changes brought about by the presence of immunogens in the haemolymph to those brought about by AKH, there is no release of endogenous AKH after injection of laminarin or LPS. A direct effect of the immunogens on release of neutral lipids by the fat body cannot be demonstrated in vitro, and the mechanism by which hyperlipaemia is induced during immune challenge remains uncertain. PMID:15121454

  18. Hormones

    MedlinePlus

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

  19. Energy-Dependent Modulation of Glucagon-Like Signaling in Drosophila via the AMP-Activated Protein Kinase

    PubMed Central

    Braco, Jason T.; Gillespie, Emily L.; Alberto, Gregory E.; Brenman, Jay E.; Johnson, Erik C.

    2012-01-01

    Adipokinetic hormone (AKH) is the equivalent of mammalian glucagon, as it is the primary insect hormone that causes energy mobilization. In Drosophila, current knowledge of the mechanisms regulating AKH signaling is limited. Here, we report that AMP-activated protein kinase (AMPK) is critical for normal AKH secretion during periods of metabolic challenges. Reduction of AMPK in AKH cells causes a suite of behavioral and physiological phenotypes resembling AKH cell ablations. Specifically, reduced AMPK function increases life span during starvation and delays starvation-induced hyperactivity. Neither AKH cell survival nor gene expression is significantly impacted by reduced AMPK function. AKH immunolabeling was significantly higher in animals with reduced AMPK function; this result is paralleled by genetic inhibition of synaptic release, suggesting that AMPK promotes AKH secretion. We observed reduced secretion in AKH cells bearing AMPK mutations employing a specific secretion reporter, confirming that AMPK functions in AKH secretion. Live-cell imaging of wild-type AKH neuroendocrine cells shows heightened excitability under reduced sugar levels, and this response was delayed and reduced in AMPK-deficient backgrounds. Furthermore, AMPK activation in AKH cells increases intracellular calcium levels in constant high sugar levels, suggesting that the underlying mechanism of AMPK action is modification of ionic currents. These results demonstrate that AMPK signaling is a critical feature that regulates AKH secretion, and, ultimately, metabolic homeostasis. The significance of these findings is that AMPK is important in the regulation of glucagon signaling, suggesting that the organization of metabolic networks is highly conserved and that AMPK plays a prominent role in these networks. PMID:22798489

  20. Energy-dependent modulation of glucagon-like signaling in Drosophila via the AMP-activated protein kinase.

    PubMed

    Braco, Jason T; Gillespie, Emily L; Alberto, Gregory E; Brenman, Jay E; Johnson, Erik C

    2012-10-01

    Adipokinetic hormone (AKH) is the equivalent of mammalian glucagon, as it is the primary insect hormone that causes energy mobilization. In Drosophila, current knowledge of the mechanisms regulating AKH signaling is limited. Here, we report that AMP-activated protein kinase (AMPK) is critical for normal AKH secretion during periods of metabolic challenges. Reduction of AMPK in AKH cells causes a suite of behavioral and physiological phenotypes resembling AKH cell ablations. Specifically, reduced AMPK function increases life span during starvation and delays starvation-induced hyperactivity. Neither AKH cell survival nor gene expression is significantly impacted by reduced AMPK function. AKH immunolabeling was significantly higher in animals with reduced AMPK function; this result is paralleled by genetic inhibition of synaptic release, suggesting that AMPK promotes AKH secretion. We observed reduced secretion in AKH cells bearing AMPK mutations employing a specific secretion reporter, confirming that AMPK functions in AKH secretion. Live-cell imaging of wild-type AKH neuroendocrine cells shows heightened excitability under reduced sugar levels, and this response was delayed and reduced in AMPK-deficient backgrounds. Furthermore, AMPK activation in AKH cells increases intracellular calcium levels in constant high sugar levels, suggesting that the underlying mechanism of AMPK action is modification of ionic currents. These results demonstrate that AMPK signaling is a critical feature that regulates AKH secretion, and, ultimately, metabolic homeostasis. The significance of these findings is that AMPK is important in the regulation of glucagon signaling, suggesting that the organization of metabolic networks is highly conserved and that AMPK plays a prominent role in these networks. PMID:22798489

  1. Conformational study on an insect neuropeptide of the AKH/RPCH-family by combined 1H NMR spectroscopy and molecular mechanics.

    PubMed

    Zubrzycki, I Z; Gäde, G

    1994-01-14

    Peptides of the AKH/RPCH family are mainly involved in influencing energy metabolism in insects, i.e., regulating carbohydrate and/or lipid breakdown in the fat body. We have studied the solution conformation of a member of this family, the peptide Emp-AKH from praying mantis. It has been characterized by use of two dimensional nuclear magnetic resonance spectroscopy and molecular modelling. The proton spectrum of the Emp-AKH peptide was assigned by sequential assignment procedure. Proton-proton distances were derived from the volumes of cross-peaks in two dimensional nuclear Overhauser enhancement spectra. The three dimensional structure was built using Evans & Sutherland molecular modelling station. Our data indicate that the Emp-AKH peptide has adopted a beta-sheet structure for amino acids 1 to 5 and a beta-turn for amino acids at positions 5 to 8. The type of turn appears to be a Non-specific beta-turn. PMID:8292025

  2. Metabolic regulation and behavior: how hunger produces arousal - an insect study.

    PubMed

    Wicher, Dieter

    2007-12-01

    The metabolic state affects the level of general activity of an organism. Satiety is related to relaxation while hunger is coupled to elevated activity which supports the chance to balance the energy deficiency. The unrestricted food availability in modern industrial nations along with no required locomotor activity are risk factors to develop disorders such as obesity. One of the strategies to find new targets for future treatment of metabolic disorders in men is to gain detailed knowledge of molecular and cellular mechanisms involved in the regulation of metabolic homeostasis in less complex, i.e. invertebrate systems. This review reports recent molecular studies in insects about how hunger signals may be linked to global activation. Adipokinetic peptide hormones (AKHs) are the insect counterpart to the mammalian glucagon. They are released upon lack of energy and mobilize internal fuel reserves. In addition, AKHs stimulate the locomotor activity which involves their activity within the central nervous system. In the cockroach Periplaneta americana various neurons express the AKH receptor. Some of these, the dorsal unpaired median (DUM) neurons belonging to a general arousal system, release the biogenic amine octopamine, the insect counterpart to mammalian adrenergic hormones. The two Periplaneta AKHs activate Gs proteins, and AKH I also potently activates Gq proteins. AKH I and - less effectively - AKH II accelerate spiking of DUM neurons via an increase of a pacemaking Ca2+ current. Systemically injected AKH I stimulates locomotion in contrast to AKH II. This behavioral difference corresponds to the different effectiveness of the AKHs on the level of G-proteins. PMID:18220952

  3. Comparative peptidomics of four related hemipteran species: Pyrokinins, myosuppressin, corazonin, adipokinetic hormone, sNPF, and periviscerokinins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We performed the first comprehensive peptidomic analysis of neurohormones from hemipteran insects by analyzing the neuropeptides of two major neurohemal organs, namely the corpora cardiaca and abdominal perisympathetic organs. For the experiments we selected four related species of polyphagous stin...

  4. The Neuropeptide Allatostatin A Regulates Metabolism and Feeding Decisions in Drosophila

    PubMed Central

    Hentze, Julie L.; Carlsson, Mikael A.; Kondo, Shu; Nässel, Dick R.; Rewitz, Kim F.

    2015-01-01

    Coordinating metabolism and feeding is important to avoid obesity and metabolic diseases, yet the underlying mechanisms, balancing nutrient intake and metabolic expenditure, are poorly understood. Several mechanisms controlling these processes are conserved in Drosophila, where homeostasis and energy mobilization are regulated by the glucagon-related adipokinetic hormone (AKH) and the Drosophila insulin-like peptides (DILPs). Here, we provide evidence that the Drosophila neuropeptide Allatostatin A (AstA) regulates AKH and DILP signaling. The AstA receptor gene, Dar-2, is expressed in both the insulin and AKH producing cells. Silencing of Dar-2 in these cells results in changes in gene expression and physiology associated with reduced DILP and AKH signaling and animals lacking AstA accumulate high lipid levels. This suggests that AstA is regulating the balance between DILP and AKH, believed to be important for the maintenance of nutrient homeostasis in response to changing ratios of dietary sugar and protein. Furthermore, AstA and Dar-2 are regulated differentially by dietary carbohydrates and protein and AstA-neuronal activity modulates feeding choices between these types of nutrients. Our results suggest that AstA is involved in assigning value to these nutrients to coordinate metabolic and feeding decisions, responses that are important to balance food intake according to metabolic needs. PMID:26123697

  5. Hormone levels

    MedlinePlus

    Blood or urine tests can determine the levels of various hormones in the body. This includes reproductive hormones, thyroid hormones, adrenal hormones, pituitary hormones, and many others. For more information, see: ...

  6. Changes in lipophorins are related to the activation of phenoloxidase in the haemolymph of Locusta migratoria in response to injection of immunogens.

    PubMed

    Mullen, L; Goldsworthy, G

    2003-07-01

    In Locusta migratoria, activation of phenoloxidase in the haemolymph in response to injection of laminarin is age-dependent: being absent in fifth instar nymphs and newly emerged adults, and only becoming evident four days after the final moult. This pattern of change in phenoloxidase activation correlates with the pattern of change in the concentration of apolipophorin-III (apoLp-III) in the haemolymph. Injection of a conspecific adipokinetic hormone (Lom-AKH-I) has no effect on the phenoloxidase response in nymphs or newly emerged adults but, in adults older than four days, co-injection of the hormone with laminarin prolongs the activation of phenoloxidase in the haemolymph: a similar enhancement of the response to laminarin is observed in locusts that have been starved for 48 h but not injected with AKH-I. During most of the fifth stadium, injection of laminarin results in a decrease in the level of prophenoloxidase in the haemolymph; an effect that is not observed in adults of any age. Marked changes in the concentration of apoLp-III, and the formation of LDLp in the haemolymph, are observed after injection of laminarin (or LPS) and these are remarkably similar, at least qualitatively, to those that occur after injection of AKH-I. The involvement of lipophorins in the activation of locust prophenoloxidase in response to immunogens is discussed. PMID:12826093

  7. Dibutyl Phthalate Exposure Disrupts Evolutionarily Conserved Insulin and Glucagon-Like Signaling in Drosophila Males.

    PubMed

    Williams, Michael J; Wiemerslage, Lyle; Gohel, Priya; Kheder, Sania; Kothegala, Lakshmi V; Schiöth, Helgi B

    2016-06-01

    Phthalate diesters are commonly used as industrial plasticisers, as well as in cosmetics and skin care products, as a result people are constantly exposed to these xenobiotics. Recent epidemiological studies have found a correlation between circulating phthalate levels and type 2 diabetes, whereas animal studies indicate that phthalates are capable of disrupting endocrine signaling. Nonetheless, how phthalates interfere with metabolic function is still unclear. Here, we show that feeding Drosophila males the xenobiotic dibutyl phthalate (DBP) affects conserved insulin- and glucagon-like signaling. We report that raising flies on food containing DBP leads to starvation resistance, increased lipid storage, hyperglycemia, and hyperphagia. We go on to show that the starvation-resistance phenotype can be rescued by overexpression of the glucagon analogue adipokinetic hormone (Akh). Furthermore, although acute DBP exposure in adult flies is able to affect insulin levels, only chronic feeding influences Akh expression. We establish that raising flies on DBP-containing food or feeding adults DBP food affects the expression of homologous genes involved in xenobiotic and lipid metabolism (AHR [Drosophila ss], NR1I2 [Hr96], ABCB1 [MDR50], ABCC3 [MRP], and CYP3A4 [Cyp9f2]). Finally, we determined that the expression of these genes is also influenced by Akh. Our results provide comprehensive evidence that DBP can disrupt metabolism in Drosophila males, by regulating genes involved in glucose, lipid, and xenobiotic metabolism. PMID:27100621

  8. Prediction of Scylla olivacea (Crustacea; Brachyura) peptide hormones using publicly accessible transcriptome shotgun assembly (TSA) sequences.

    PubMed

    Christie, Andrew E

    2016-05-01

    The aquaculture of crabs from the genus Scylla is of increasing economic importance for many Southeast Asian countries. Expansion of Scylla farming has led to increased efforts to understand the physiology and behavior of these crabs, and as such, there are growing molecular resources for them. Here, publicly accessible Scylla olivacea transcriptomic data were mined for putative peptide-encoding transcripts; the proteins deduced from the identified sequences were then used to predict the structures of mature peptide hormones. Forty-nine pre/preprohormone-encoding transcripts were identified, allowing for the prediction of 187 distinct mature peptides. The identified peptides included isoforms of adipokinetic hormone-corazonin-like peptide, allatostatin A, allatostatin B, allatostatin C, bursicon β, CCHamide, corazonin, crustacean cardioactive peptide, crustacean hyperglycemic hormone/molt-inhibiting hormone, diuretic hormone 31, eclosion hormone, FMRFamide-like peptide, HIGSLYRamide, insulin-like peptide, intocin, leucokinin, myosuppressin, neuroparsin, neuropeptide F, orcokinin, pigment dispersing hormone, pyrokinin, red pigment concentrating hormone, RYamide, short neuropeptide F, SIFamide and tachykinin-related peptide, all well-known neuropeptide families. Surprisingly, the tissue used to generate the transcriptome mined here is reported to be testis. Whether or not the testis samples had neural contamination is unknown. However, if the peptides are truly produced by this reproductive organ, it could have far reaching consequences for the study of crustacean endocrinology, particularly in the area of reproductive control. Regardless, this peptidome is the largest thus far predicted for any brachyuran (true crab) species, and will serve as a foundation for future studies of peptidergic control in members of the commercially important genus Scylla.

  9. Imbalanced Hemolymph Lipid Levels Affect Feeding Motivation in the Two-Spotted Cricket, Gryllus bimaculatus.

    PubMed

    Konuma, Takahiro; Tsukamoto, Yusuke; Nagasawa, Hiromichi; Nagata, Shinji

    2016-01-01

    Insect feeding behavior is regulated by many intrinsic factors, including hemolymph nutrient levels. Adipokinetic hormone (AKH) is a peptide factor that modulates hemolymph nutrient levels and regulates the nutritional state of insects by triggering the transfer of lipids into the hemolymph. We recently demonstrated that RNA interference (RNAi)-mediated knockdown of the AKH receptor (AKHR) reduces hemolymph lipid levels, causing an increase in the feeding frequency of the two-spotted cricket, Gryllus bimaculatus. This result indicated that reduced hemolymph lipid levels might motivate crickets to feed. In the present study, to elucidate whether hemolymph lipid levels contribute to insect feeding behavior, we attempted to manipulate hemolymph lipid levels via the lipophorin (Lp)-mediated lipid transferring system in G. bimaculatus. Of the constituent proteins in Lp, we focused on apolipophorin-III (GrybiApoLp-III) because of its possible role in facilitating lipid mobilization. First, we used RNAi to reduce the expression of GrybiApoLp-III. RNAi-mediated knockdown of GrybiApoLp-III had little effect on basal hemolymph lipid levels and the amount of food intake. In addition, hemolymph lipid levels remained static even after injecting AKH into GrybiApoLp-IIIRNAi crickets. These observations indicated that ApoLp-III does not maintain basal hemolymph lipid levels in crickets fed ad libitum, but is necessary for mobilizing lipid transfer into the hemolymph following AKH stimulation. Second, Lp (containing lipids) was injected into the hemolymph to induce a temporary increase in hemolymph lipid levels. Consequently, the initiation of feeding was delayed in a dose-dependent manner, indicating that increased hemolymph lipid levels reduced the motivation to feed. Taken together, these data validate the importance of basal hemolymph lipid levels in the control of energy homeostasis and for regulating feeding behavior in crickets. PMID:27144650

  10. Imbalanced Hemolymph Lipid Levels Affect Feeding Motivation in the Two-Spotted Cricket, Gryllus bimaculatus

    PubMed Central

    Konuma, Takahiro; Tsukamoto, Yusuke; Nagasawa, Hiromichi; Nagata, Shinji

    2016-01-01

    Insect feeding behavior is regulated by many intrinsic factors, including hemolymph nutrient levels. Adipokinetic hormone (AKH) is a peptide factor that modulates hemolymph nutrient levels and regulates the nutritional state of insects by triggering the transfer of lipids into the hemolymph. We recently demonstrated that RNA interference (RNAi)-mediated knockdown of the AKH receptor (AKHR) reduces hemolymph lipid levels, causing an increase in the feeding frequency of the two-spotted cricket, Gryllus bimaculatus. This result indicated that reduced hemolymph lipid levels might motivate crickets to feed. In the present study, to elucidate whether hemolymph lipid levels contribute to insect feeding behavior, we attempted to manipulate hemolymph lipid levels via the lipophorin (Lp)-mediated lipid transferring system in G. bimaculatus. Of the constituent proteins in Lp, we focused on apolipophorin-III (GrybiApoLp-III) because of its possible role in facilitating lipid mobilization. First, we used RNAi to reduce the expression of GrybiApoLp-III. RNAi-mediated knockdown of GrybiApoLp-III had little effect on basal hemolymph lipid levels and the amount of food intake. In addition, hemolymph lipid levels remained static even after injecting AKH into GrybiApoLp-IIIRNAi crickets. These observations indicated that ApoLp-III does not maintain basal hemolymph lipid levels in crickets fed ad libitum, but is necessary for mobilizing lipid transfer into the hemolymph following AKH stimulation. Second, Lp (containing lipids) was injected into the hemolymph to induce a temporary increase in hemolymph lipid levels. Consequently, the initiation of feeding was delayed in a dose-dependent manner, indicating that increased hemolymph lipid levels reduced the motivation to feed. Taken together, these data validate the importance of basal hemolymph lipid levels in the control of energy homeostasis and for regulating feeding behavior in crickets. PMID:27144650

  11. Growth Hormone

    MedlinePlus

    ... the dose of glucose. Growth hormone stimulates the production of insulin-like growth factor-1 (IGF-1) . ... regular intervals for years afterward to monitor GH production and to detect tumor recurrence. Other blood tests ...

  12. Hormone Therapy

    MedlinePlus

    ... based lubricants include petroleum jelly, baby oil, or mineral oil. Oil-based types should not be used ... caused by low levels of these hormones. Hysterectomy: Removal of the uterus. Menopause: The time in a ...

  13. Food odors trigger an endocrine response that affects food ingestion and metabolism.

    PubMed

    Lushchak, Oleh V; Carlsson, Mikael A; Nässel, Dick R

    2015-08-01

    Food odors stimulate appetite and innate food-seeking behavior in hungry animals. The smell of food also induces salivation and release of gastric acid and insulin. Conversely, sustained odor exposure may induce satiation. We demonstrate novel effects of food odors on food ingestion, metabolism and endocrine signaling in Drosophila melanogaster. Acute exposure to attractive vinegar odor triggers a rapid and transient increase in circulating glucose, and a rapid upregulation of genes encoding the glucagon-like hormone adipokinetic hormone (AKH), four insulin-like peptides (DILPs) and some target genes in peripheral tissues. Sustained exposure to food odors, however, decreases food intake. Hunger-induced strengthening of synaptic signaling from olfactory sensory neurons (OSNs) to brain neurons increases food-seeking behavior, and conversely fed flies display reduced food odor sensitivity and feeding. We show that increasing the strength of OSN signaling chronically by genetic manipulation of local peptide neuromodulation reduces feeding, elevates carbohydrates and diminishes lipids. Furthermore, constitutively strengthened odor sensitivity altered gene transcripts for AKH, DILPs and some of their targets. Thus, we show that food odor can induce a transient anticipatory endocrine response, and that boosted sensitivity to this odor affects food intake, as well as metabolism and hormonal signaling.

  14. Activation of the lipid droplet controls the rate of lipolysis of triglycerides in the insect fat body.

    PubMed

    Patel, Rajesh T; Soulages, Jose L; Hariharasundaram, Balaji; Arrese, Estela L

    2005-06-17

    The hydrolysis of triglyceride (TG) stored in the lipid droplets of the insect fat body is under hormonal regulation by the adipokinetic hormone (AKH), which triggers a rapid activation cAMP-dependent kinase cascade (protein kinase A (PKA)). The role of phosphorylation on two components of the lipolytic process, the TG-lipase and the lipid droplet, was investigated in fat body adipocytes. The activity of purified TG-lipase determined using in vivo TG-radiolabeled lipid droplets was unaffected by the phosphorylation of the lipase. However, the activity of purified lipase was 2.4-fold higher against lipid droplets isolated from hormone-stimulated fat bodies than against lipid droplets isolated from unstimulated tissue. In vivo stimulation of lipolysis promotes a rapid phosphorylation of a lipid droplet protein with an apparent mass of 42-44 kDa. This protein was identified as "Lipid Storage Droplet Protein 1" (Lsdp1). In vivo phosphorylation of this protein reached a peak approximately 10 min after the injection of AKH. Supporting a role of Lsdp1 in lipolysis, maximum TG-lipase activity was also observed with lipid droplets isolated 10 min after hormonal stimulation. The activation of lipolysis was reconstituted in vitro using purified insect PKA and TG-lipase and lipid droplets. In vitro phosphorylation of lipid droplets catalyzed by PKA enhanced the phosphorylation of Lsdp1 and the lipolytic rate of the lipase, demonstrating a prominent role PKA and protein phosphorylation on the activation of the lipid droplets. AKH-induced changes in the properties of the substrate do not promote a tight association of the lipase with the lipid droplets. It is concluded that the lipolysis in fat body adipocytes is controlled by the activation of the lipid droplet. This activation is achieved by PKA-mediated phosphorylation of the lipid droplet. Lsdp1 is the main target of PKA, suggesting that this protein is a major player in the activation of lipolysis in insects.

  15. Opposing effects of dietary protein and sugar regulate a transcriptional target of Drosophila insulin-like peptide signaling.

    PubMed

    Buch, Susanne; Melcher, Christoph; Bauer, Matthias; Katzenberger, Joerg; Pankratz, Michael J

    2008-04-01

    Specific neurosecretory cells of the Drosophila brain express insulin-like peptides (dilps), which regulate growth, glucose homeostasis, and aging. Through microarray analysis of flies in which the insulin-producing cells (IPCs) were ablated, we identified a target gene, target of brain insulin (tobi), that encodes an evolutionarily conserved alpha-glucosidase. Flies with lowered tobi levels are viable, whereas tobi overexpression causes severe growth defects and a decrease in body glycogen. Interestingly, tobi expression is increased by dietary protein and decreased by dietary sugar. This pattern is reminiscent of mammalian glucagon secretion, which is increased by protein intake and decreased by sugar intake, suggesting that tobi is regulated by a glucagon analog. tobi expression is also eliminated upon ablation of neuroendocrine cells that produce adipokinetic hormone (AKH), an analog of glucagon. tobi is thus a target of the insulin- and glucagon-like signaling system that responds oppositely to dietary protein and sugar.

  16. Intra-myocellular fatty acid metabolism plays a critical role in mediating responses to dietary restriction in Drosophila melanogaster

    PubMed Central

    Katewa, Subhash D.; Demontis, Fabio; Kolipinski, Marysia; Hubbard, Allan; Gill, Matthew S.; Perrimon, Norbert; Melov, Simon; Kapahi, Pankaj

    2012-01-01

    Summary Changes in fat content have been associated with dietary restriction (DR), but whether they play a causal role in mediating various responses to DR remains unknown. We demonstrate that upon DR, Drosophila melanogaster shift their metabolism towards increasing both fatty acid synthesis and breakdown, which is required for various responses to DR. Inhibition of fatty acid synthesis or oxidation genes specifically in the muscle tissue inhibited lifespan extension upon DR. Furthermore, DR enhances spontaneous activity of flies which was found to be dependent on the enhanced fatty acid metabolism. This increase in activity was found to be at least partially required for the lifespan extension upon DR. Over-expression of adipokinetic hormone (dAKH), the functional ortholog of glucagon, enhances fat metabolism, spontaneous activity and lifespan. Together, these results suggest that enhanced fat metabolism in the muscle and physical activity play a key role in the protective effects of DR. PMID:22768842

  17. Endocrine control of TAG lipase in the fat body of the migratory locust, Locusta migratoria.

    PubMed

    Auerswald, Lutz; Gäde, Gerd

    2006-10-01

    Aspects of the role and activation of the enzyme triacylglycerol lipase (TAG lipase) in the fat body of the migratory locust Locusta migratoria were investigated. TAG lipase is under the hormonal control of the three endogenous adipokinetic peptides of the migratory locust, Locmi-AKH-I, Locmi-AKH-II and Locmi-AKH-III. Injection of low doses (5-10 pmol) of each peptide causes an increase in lipase activity. The activation of lipase is time dependent: an elevated activity was recorded 15 min after injection of 10 pmol Locmi-AKH-I and maximum activation was reached after 45-60 min. The activation of TAG lipase is also dose-dependent. Doses of 2 pmol of each Locmi-AKH had no effect, whereas 5 pmol caused a significant activation. Maximum activation is reached with a dose of 10 pmol. Analogues of the second messengers cAMP (cpt-cAMP) and IP(3) (F-IP(3)) both activate the enzyme glycogen phosphorylase whereas only cpt-cAMP, but not F-IP(3), activates TAG lipase; cpt-cAMP elevates the lipid levels in the haemolymph. Activation of lipase is specific to the three endogenous AKH peptides: 5 pmol of the endogenous peptide Locmi-HrTH and 10 pmol of corazonin failed to activate lipase. High doses of octopamine did not activate lipase nor did they elevate the lipid concentration in the haemolymph. TAG lipase is stimulated by flight activity but activation is slower than that of glycogen phosphorylase: after 30 min of flight or after 5 min of flight plus 1h of subsequent rest, activity of TAG lipase is increased, but not immediately after 5 min of flight. In contrast, glycogen phosphorylase is activated significantly after 5 min of flight. These activation patterns of the two enzymes mirror-image the concentration of their substrates in the haemolymph: there is a significant decrease in the concentration of carbohydrates after 5 min of flight, whereas no change of the concentration of lipids can be measured after such short time of flight activity; however, a subsequent rest

  18. Hormone impostors

    SciTech Connect

    Colborn, T.; Dumanoski, D.; Myers, J.P.

    1997-01-01

    This article discusses the accumulating evidence that some synthetic chemicals disrupt hormones in one way or another. Some mimic estrogen and others interfere with other parts of the body`s control or endocrine system such as testosterone and thyroid metabolism. Included are PCBs, dioxins, furans, atrazine, DDT. Several short sidebars highlight areas where there are or have been particular problems.

  19. The satiety signaling neuropeptide perisulfakinin inhibits the activity of central neurons promoting general activity.

    PubMed

    Wicher, Dieter; Derst, Christian; Gautier, Hélène; Lapied, Bruno; Heinemann, Stefan H; Agricola, Hans-Jürgen

    2007-01-01

    The metabolic state is one of the determinants of the general activity level. Satiety is related to resting or sleep whereas hunger correlates to wakefulness and activity. The counterpart to the mammalian satiety signal cholecystokinin (CCK) in insects are the sulfakinins. The aim of this study was to resolve the mechanism by which the antifeedant activity of perisulfakinin (PSK) in Periplaneta americana is mediated. We identified the sources of PSK which is used both as hormone and as paracrine messenger. PSK is found in the neurohemal organ of the brain and in nerve endings throughout the central nervous system. To correlate the distributions of PSK and its receptor (PSKR), we cloned the gene coding for PSKR and provide evidence for its expression within the nervous system. It occurs only in a few neurons, among them are the dorsal unpaired median (DUM) neurons which release octopamine thereby regulating the general level of activity. Application of PSK to DUM neurons attenuated the spiking frequency (EC(50)=11pM) due to reduction of a pacemaker Ca(2+) current through cAMP-inhibited pTRPgamma channels. PSK increased the intracellular cAMP level while decreasing the intracellular Ca(2+) concentration in DUM neurons. Thus, the satiety signal conferred by PSK acts antagonistically to the hunger signal, provided by the adipokinetic hormone (AKH): PSK depresses the electrical activity of DUM neurons by inhibiting the pTRPgamma channel that is activated by AKH under conditions of food shortage. PMID:18946521

  20. Urbilaterian origin of paralogous GnRH and corazonin neuropeptide signalling pathways.

    PubMed

    Tian, Shi; Zandawala, Meet; Beets, Isabel; Baytemur, Esra; Slade, Susan E; Scrivens, James H; Elphick, Maurice R

    2016-01-01

    Gonadotropin-releasing hormone (GnRH) is a key regulator of reproductive maturation in humans and other vertebrates. Homologs of GnRH and its cognate receptor have been identified in invertebrates-for example, the adipokinetic hormone (AKH) and corazonin (CRZ) neuropeptide pathways in arthropods. However, the precise evolutionary relationships and origins of these signalling systems remain unknown. Here we have addressed this issue with the first identification of both GnRH-type and CRZ-type signalling systems in a deuterostome-the echinoderm (starfish) Asterias rubens. We have identified a GnRH-like neuropeptide (pQIHYKNPGWGPG-NH2) that specifically activates an A. rubens GnRH-type receptor and a novel neuropeptide (HNTFTMGGQNRWKAG-NH2) that specifically activates an A. rubens CRZ-type receptor. With the discovery of these ligand-receptor pairs, we demonstrate that the vertebrate/deuterostomian GnRH-type and the protostomian AKH systems are orthologous and the origin of a paralogous CRZ-type signalling system can be traced to the common ancestor of the Bilateria (Urbilateria). PMID:27350121

  1. Urbilaterian origin of paralogous GnRH and corazonin neuropeptide signalling pathways

    PubMed Central

    Tian, Shi; Zandawala, Meet; Beets, Isabel; Baytemur, Esra; Slade, Susan E.; Scrivens, James H.; Elphick, Maurice R.

    2016-01-01

    Gonadotropin-releasing hormone (GnRH) is a key regulator of reproductive maturation in humans and other vertebrates. Homologs of GnRH and its cognate receptor have been identified in invertebrates–for example, the adipokinetic hormone (AKH) and corazonin (CRZ) neuropeptide pathways in arthropods. However, the precise evolutionary relationships and origins of these signalling systems remain unknown. Here we have addressed this issue with the first identification of both GnRH-type and CRZ-type signalling systems in a deuterostome–the echinoderm (starfish) Asterias rubens. We have identified a GnRH-like neuropeptide (pQIHYKNPGWGPG-NH2) that specifically activates an A. rubens GnRH-type receptor and a novel neuropeptide (HNTFTMGGQNRWKAG-NH2) that specifically activates an A. rubens CRZ-type receptor. With the discovery of these ligand-receptor pairs, we demonstrate that the vertebrate/deuterostomian GnRH-type and the protostomian AKH systems are orthologous and the origin of a paralogous CRZ-type signalling system can be traced to the common ancestor of the Bilateria (Urbilateria). PMID:27350121

  2. The Satiety Signaling Neuropeptide Perisulfakinin Inhibits the Activity of Central Neurons Promoting General Activity

    PubMed Central

    Wicher, Dieter; Derst, Christian; Gautier, Hélène; Lapied, Bruno; Heinemann, Stefan H.; Agricola, Hans-Jürgen

    2007-01-01

    The metabolic state is one of the determinants of the general activity level. Satiety is related to resting or sleep whereas hunger correlates to wakefulness and activity. The counterpart to the mammalian satiety signal cholecystokinin (CCK) in insects are the sulfakinins. The aim of this study was to resolve the mechanism by which the antifeedant activity of perisulfakinin (PSK) in Periplaneta americana is mediated. We identified the sources of PSK which is used both as hormone and as paracrine messenger. PSK is found in the neurohemal organ of the brain and in nerve endings throughout the central nervous system. To correlate the distributions of PSK and its receptor (PSKR), we cloned the gene coding for PSKR and provide evidence for its expression within the nervous system. It occurs only in a few neurons, among them are the dorsal unpaired median (DUM) neurons which release octopamine thereby regulating the general level of activity. Application of PSK to DUM neurons attenuated the spiking frequency (EC50=11pM) due to reduction of a pacemaker Ca2+ current through cAMP-inhibited pTRPγ channels. PSK increased the intracellular cAMP level while decreasing the intracellular Ca2+ concentration in DUM neurons. Thus, the satiety signal conferred by PSK acts antagonistically to the hunger signal, provided by the adipokinetic hormone (AKH): PSK depresses the electrical activity of DUM neurons by inhibiting the pTRPγ channel that is activated by AKH under conditions of food shortage. PMID:18946521

  3. Types of hormone therapy

    MedlinePlus

    ... types of hormone therapy; Hormone replacement therapy - types; Menopause - types of hormone therapy; HT - types; Menopausal hormone ... Menopause symptoms include: Hot flashes Night sweats Sleep problems Vaginal dryness Anxiety Moodiness Less interest in sex ...

  4. A novel function of red pigment-concentrating hormone in crustaceans: Porcellio scaber (Isopoda) as a model species.

    PubMed

    Zralá, Jana; Kodrík, Dalibor; Zahradnícková, Helena; Zemek, Rostislav; Socha, Radomír

    2010-04-01

    The RP HPLC and LC/MS QTOF analyses of the methanolic CNS extract from isopod crustacean the woodlouse, Porcellio scaber revealed a presence of the red pigment-concentrating hormone (Panbo-RPCH) in this species. It has been shown that this neuropeptide plays a role in mobilization of energy stores: topical treatments of P. scaber individuals by Panbo-RPCH in a concentration 20 pmol/microl increased the level of glucose in haemolymph about 4 times, while the level of trehalose was only doubled. The results demonstrated that glucose was the main carbohydrate mobilized by the Panbo-RPCH treatment: glucose was responsible for about 97% of total carbohydrate increasing. Despite the demonstration of hyperglycaemic activity of Panbo-RPCH, no stimulatory effect of this hormone on the locomotory activity of P. scaber was observed. The present study is the first discovery of an occurrence of Panbo-RPCH and its hyperglycaemic activity in the representative of the isopod crustaceans. The relationship of the function of Panbo-RPCH in P. scaber to the role of this neuropeptide and adipokinetic hormones in insects is discussed.

  5. Growth hormone.

    PubMed

    Bidlingmaier, Martin; Strasburger, Christian J

    2010-01-01

    Human growth hormone (hGH) is a proteohormone secreted by the pituitary gland. It acts through binding to the hGH receptor, inducing either direct effects or initiating the production of insulin-like growth-factor I (IGF-I), the most important mediator of hGH effects. Growth hormone is primarily known to promote longitudinal growth in children and adolescents, but has also various important metabolic functions throughout adult life. Effects of hGH on the adult organism are well established from studies with recombinant growth hormone (rhGH) therapy in growth hormone deficient subjects. In this particular group of patients, replacement of hGH leads to increased lipolysis and lean body mass, decreased fat mass, improvements in VO(2max), and maximal power output. Although extrapolation from these findings to the situation in well trained healthy subjects is impossible, and controlled studies in healthy subjects are scarce, abuse of hGH seems to be popular among athletes trying to enhance physical performance. Detection of the application of rhGH is difficult, especially because the amino acid sequence of rhGH is identical to the major 22,000 Da isoform of hGH normally secreted by the pituitary. Furthermore, some physiological properties of hGH secretion also hindered the development of a doping test: secreted in a pulsatile manner, it has a very short half-life in circulation, which leads to highly variable serum levels. Concentration alone therefore cannot prove the exogenous administration of hGH.Two approaches have independently been developed for the detection of hGH doping: The so-called "marker approach" investigates changes in hGH-dependent parameters like IGF-I or components of bone and collagen metabolism, which are increased after hGH injection. In contrast, the so-called "isoform approach" directly analyses the spectrum of molecular isoforms in circulation: the pituitary gland secretes a spectrum of homo- and heterodimers and - multimers of a variable

  6. [Incretin hormones].

    PubMed

    Cáp, J

    2011-04-01

    Incretin hormones are peptides that are secreted from endocrine cell of gastrointestinal tract after nutrient ingestion and stimulate insulin secretion. Glucosodependent Insulinotropic Peptide--GIP is released from K-cells of duodenum and proximal jejunum, recently GIP synthesis has been proved in pancreatic alpha cells. Besides the incretin effect causes GIP increased lipogenesis and decreased lipolysis in fat tissue, increased bone formation and decreased resorption and has protective and proliferative effect on CNS neurons. Both GIP agonists (to treat diabetes) and antagonist (to treat obesity) are being studied. Another incretin hormone is derived in intestinal I-cells by posttranslational processing of proglucagon--glucagon-like peptides 1 and 2 (GLP-1 and GLP-2). GLP-1 stimulates insuline production and inhibits glucagon secretion, exerts proliferative and antiapoptotic effect on beta-cells. Via receptors on vagal nerve and central mechanisms decreases food intake and decreases body weight. By deceleration of gastric emptying it attenuates increases in meal-associated blood glucose levels. It exerts cardioprotective effects. GLP-1 receptors have been proved in liver recently but decreased liver glucose production and increased glucose uptake by liver and muscle are mediated indirectly by altering insulin and glucagons levels. GLP-2 stimulates enterocytes proliferation, up-regulates intestinal nutrient transport, improves intestinal barrier function, and inhibits gastric and intestinal motility. GLP-2 also reduces bone resorption. PMID:21612069

  7. Suppression of conditioned odor approach by feeding is independent of taste and nutritional value in Drosophila.

    PubMed

    Gruber, Franz; Knapek, Stephan; Fujita, Michiko; Matsuo, Koichiro; Bräcker, Lasse; Shinzato, Nao; Siwanowicz, Igor; Tanimura, Teiichi; Tanimoto, Hiromu

    2013-03-18

    Motivation controls behavior [1]. A variety of food-related behaviors undergo motivational modulation by hunger, satiety, and other states [2-4]. Here we searched for critical satiation factors modulating approach to an odor associated with sugar reward in Drosophila melanogaster. We selectively manipulated different parameters associated with feeding, such as internal glucose levels, and determined which are required for suppressing conditioned odor approach. Surprisingly, glucose levels in the hemolymph, nutritional value, sweetness of the food, and ingested volume (above a minimal threshold) did not influence behavior suppression. Instead, we found that the total osmolarity of ingested food is a critical satiation factor. In parallel, we found that conditioned approach is transiently suppressed by artificial stimulation of adipokinetic hormone (AKH) expressing corpora cardiaca cells, which causes elevation of hemolymph carbohydrate and lipid concentrations [5, 6]. This result implies that a rise in hemolymph osmolarity, without the experience of feeding, is sufficient to satiate conditioned odor approach. AKH stimulation did not affect innate sugar preference, suggesting that multiple satiation signals control different sets of appetitive behaviors.

  8. Octopamine partially restores walking in hypokinetic cockroaches stung by the parasitoid wasp Ampulex compressa.

    PubMed

    Rosenberg, Lior Ann; Glusman, Jose Gustavo; Libersat, Frederic

    2007-12-01

    When stung by the parasitoid wasp Ampulex compressa, cockroaches Periplaneta americana enter a hypokinetic state that is characterized by little, if any, spontaneous locomotor activity. In the present study we investigate the effect of an octopamine receptor agonist and an antagonist on the locomotor behavior of stung and control cockroaches. We show that in cockroaches stung by a wasp the octopamine receptor agonist chlordimeform induces a significant increase in spontaneous walking. In good agreement, in control individuals an octopamine receptor antagonist significantly reduces walking activity. Adipokinetic hormone I (AKH-I) promotes spontaneous walking in controls but does not do so in stung individuals, which suggests that the venom effect is most probably not mediated by AKH-I. Dopamine receptor agonists or antagonists had no significant effect on the spontaneous walking of stung or control cockroaches, respectively. The effect of the octopamine receptor agonist was maximal when injected into the brain, suggesting that the wasp venom interferes with octopaminergic modulation of walking initiation in central structures of the cockroach brain. PMID:18055629

  9. Hormone Replacement Therapy

    MedlinePlus

    ... before and during menopause, the levels of female hormones can go up and down. This can cause ... hot flashes and vaginal dryness. Some women take hormone replacement therapy (HRT), also called menopausal hormone therapy, ...

  10. Growth hormone test

    MedlinePlus

    ... page: //medlineplus.gov/ency/article/003706.htm Growth hormone test To use the sharing features on this page, please enable JavaScript. The growth hormone test measures the amount of growth hormone in ...

  11. Deciding about hormone therapy

    MedlinePlus

    HRT - deciding; Estrogen replacement therapy - deciding; ERT- deciding; Hormone replacement therapy - deciding; Menopause - deciding; HT - deciding; Menopausal hormone therapy - deciding; MHT - deciding

  12. Hormones talking

    PubMed Central

    Marsch-Martínez, Nayelli; Reyes-Olalde, J. Irepan; Ramos-Cruz, Daniela; Lozano-Sotomayor, Paulina; Zúñiga-Mayo, Victor M.; de Folter, Stefan

    2012-01-01

    The proper development of fruits is important for the sexual reproduction and propagation of many plant species. The fruit of Arabidopsis derives from the fertilized gynoecium, which initiates at the center of the flower and obtains its final shape, size, and functional tissues through progressive stages of development. Hormones, specially auxins, play important roles in gynoecium and fruit patterning. Cytokinins, which act as counterparts to auxins in other plant tissues, have been studied more in the context of ovule formation and parthenocarpy. We recently studied the role of cytokinins in gynoecium and fruit patterning and found that they have more than one role during gynoecium and fruit patterning. We also compared the cytokinin response localization to the auxin response localization in these organs, and studied the effects of spraying cytokinins in young flowers of an auxin response line. In this addendum, we discuss further the implications of the observed results in the knowledge about the relationship between cytokinins and auxins at the gynoecium. PMID:23072997

  13. Hormone therapy in acne.

    PubMed

    Lakshmi, Chembolli

    2013-01-01

    Underlying hormone imbalances may render acne unresponsive to conventional therapy. Relevant investigations followed by initiation of hormonal therapy in combination with regular anti-acne therapy may be necessary if signs of hyperandrogenism are present. In addition to other factors, androgen-stimulated sebum production plays an important role in the pathophysiology of acne in women. Sebum production is also regulated by other hormones, including estrogens, growth hormone, insulin, insulin-like growth factor-1, glucocorticoids, adrenocorticotropic hormone, and melanocortins. Hormonal therapy may also be beneficial in female acne patients with normal serum androgen levels. An understanding of the sebaceous gland and the hormonal influences in the pathogenesis of acne would be essential for optimizing hormonal therapy. Sebocytes form the sebaceous gland. Human sebocytes express a multitude of receptors, including receptors for peptide hormones, neurotransmitters and the receptors for steroid and thyroid hormones. Various hormones and mediators acting through the sebocyte receptors play a role in the orchestration of pathogenetic lesions of acne. Thus, the goal of hormonal treatment is a reduction in sebum production. This review shall focus on hormonal influences in the elicitation of acne via the sebocyte receptors, pathways of cutaneous androgen metabolism, various clinical scenarios and syndromes associated with acne, and the available therapeutic armamentarium of hormones and drugs having hormone-like actions in the treatment of acne.

  14. Growth hormone deficiency - children

    MedlinePlus

    ... the same age. The child will have normal intelligence in most cases. In older children, puberty may ... hormones cause the body to make. Tests can measure these growth factors. Accurate growth hormone deficiency testing ...

  15. Hormone Health Network

    MedlinePlus

    ... Cuidadores Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types of ... Health Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types of ...

  16. Hormones and Obesity

    MedlinePlus

    ... y Cuidadores Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types ... Women's Health Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types ...

  17. Hormones and Hypertension

    MedlinePlus

    Fact Sheet Hormones and Hypertension What is hypertension? Hypertension, or chronic (long-term) high blood pressure, is a main cause of ... tobacco, alcohol, and certain medications play a part. Hormones made in the kidneys and in blood vessels ...

  18. ADH (Antidiuretic Hormone) Test

    MedlinePlus

    ... Also known as: Vasopressin; AVP Formal name: Antidiuretic Hormone; Arginine Vasopressin Related tests: Osmolality , BUN , Creatinine , Sodium , ... should know? How is it used? The antidiuretic hormone (ADH) test is used to help detect, diagnose, ...

  19. Menopause and Hormones

    MedlinePlus

    ... Consumer Information by Audience For Women Menopause and Hormones: Common Questions Share Tweet Linkedin Pin it More ... reproduction and distribution. Learn More about Menopause and Hormones Menopause--Medicines to Help You Links to other ...

  20. Aging changes in hormone production

    MedlinePlus

    The endocrine system is made up of organs and tissues that produce hormones. Hormones are natural chemicals produced in one ... hormones that control the other structures in the endocrine system. The amount of these regulating hormones stays about ...

  1. [Growth hormone treatment update].

    PubMed

    2014-02-01

    Short stature in children is a common cause for referral to pediatric endocrinologists, corresponding most times to normal variants of growth. Initially growth hormone therapy was circumscribed to children presenting growth hormone deficiency. Since the production of recombinant human hormone its use had spread to other pathologies.

  2. Immunohistochemical localisation of the hypertrehalosaemic hormone II (Cam-HrTH-II) and related peptides in the nervous system of Carausius morosus and Sarcophaga bullata.

    PubMed

    Clottens, F; Gäde, G; Huybrechts, R; De Loof, A

    1989-12-01

    A polyclonal antiserum was prepared against an N-terminal modified Cam-HrTH-II (Leu-Asn-Phe-...), one of the members of the large AKH/RPCH peptide family, first isolated from Carausius morosus. The localisation of this peptide was performed by means of immunocytochemical methods in the brain and corpora cardiaca-corpora allata complex of the stick insect, Carausius morosus and the grey fleshfly, Sarcophaga bullata. The distribution patterns of molecules reactive to the Cam-HrTH-II and the Lom-AKH-I antisera in both insect species were compared. In Carausius, both antisera reacted in the same cell bodies. In Sarcophaga, some neurons were stained by both, others only by one of the two antisera. By combining two different antisera, we demonstrated that there are no Lom-AKH-I-like molecules present in Carausius and that there must occur at least three different AKH-like molecules in the brain of Sarcophaga. One is similar to Cam-HrTH-II, the second to Lom-AKH-I and the third is an AKH/RPCH-like peptide, different from Lom-AKH-I and Cam-HrTH-II.

  3. Was sind hormone?

    NASA Astrophysics Data System (ADS)

    Karlson, P.

    1982-01-01

    Historically, the meaning of the term hormone has changed during the last decades. Morphological studies of secreting cells lead Feyrter to the concept of paracrine action of some hormones. While endocrine regulators are blood-borne, paracrine messengers reach their target cells through the diffusion in the intracellular space. Though it is rather difficult to draw a line between true hormones and hormone-like substances, valid definitions for endocrine and paracrine regulatory systems can be given. The term ‘hormonal control’ should be restricted to endocrine systems. For effectors acting by paracrine mechanisms, the term paramone is proposed in this article.

  4. Human growth hormone.

    PubMed

    Strobl, J S; Thomas, M J

    1994-03-01

    The study of human growth hormone is a little more than 100 years old. Growth hormone, first identified for its dramatic effect on longitudinal growth, is now known to exert generalized effects on protein, lipid, and carbohydrate metabolism. Additional roles for growth hormone in human physiology are likely to be discovered in the areas of sleep research and reproduction. Furthermore, there is some indication that growth hormone also may be involved in the regulation of immune function, mental well-being, and the aging process. Recombinant DNA technology has provided an abundant and safe, albeit expensive, supply of human growth hormone for human use, but the pharmacological properties of growth hormone are poor. Most growth hormone-deficient individuals exhibit a secretory defect rather than a primary defect in growth hormone production, however, and advances in our understanding of the neuroendocrine regulation of growth hormone secretion have established the basis for the use of drugs to stimulate release of endogenously synthesized growth hormone. This promises to be an important area for future drug development. PMID:8190748

  5. Hormones and endometrial carcinogenesis.

    PubMed

    Kamal, Areege; Tempest, Nicola; Parkes, Christina; Alnafakh, Rafah; Makrydima, Sofia; Adishesh, Meera; Hapangama, Dharani K

    2016-02-01

    Endometrial cancer (EC) is the commonest gynaecological cancer in the Western World with an alarmingly increasing incidence related to longevity and obesity. Ovarian hormones regulate normal human endometrial cell proliferation, regeneration and function therefore are implicated in endometrial carcinogenesis directly or via influencing other hormones and metabolic pathways. Although the role of unopposed oestrogen in the pathogenesis of EC has received considerable attention, the emerging role of other hormones in this process, such as androgens and gonadotropin-releasing hormones (GnRH) is less well recognised. This review aims to consolidate the current knowledge of the involvement of the three main endogenous ovarian hormones (oestrogens, progesterone and androgens) as well as the other hormones in endometrial carcinogenesis, to identify important avenues for future research. PMID:26966933

  6. Headaches and hormones.

    PubMed

    Pakalnis, Ann; Gladstein, Jack

    2010-06-01

    It is clear that hormones play an important role in modulating and exacerbating headaches. From an epidemiologic standpoint, we know that before puberty, incidence of new headache is similar for boys and girls. By age 18, however, most new cases of migraine occur in young women. The role of sex hormones in headache is described in the context of pubertal development. Obesity and Pseudotumor also impact headache through hormonal influences. Menstrual migraine will often present in the teenage years. Oral contraceptives may worsen or ameliorate headache. This article will introduce these concepts and help the reader become familiar with the role of hormones in headache.

  7. The mechanism of regulation of ovarian maturation by red pigment concentrating hormone in the mud crab Scylla paramamosain.

    PubMed

    Zeng, Hui; Bao, Chenchang; Huang, Huiyang; Ye, Haihui; Li, Shaojing

    2016-01-01

    In this study a full-length cDNA (Sp-RPCH) was cloned from the eyestalk ganglia of the mud crab Scylla paramamosain. Sp-RPCH is 660 base pairs in length and its open reading frame encodes a precursor that is predicted to be processed into a 25-residue signal peptide, a mature red pigment concentrating hormone (RPCH, an octapeptide), and a 75-residue precursor-related peptide. Phylogenetic analysis indicates that it clusters with other crustacean RPCHs and belongs to the adipokinetic hormone/RPCH peptide superfamily. Sp-RPCH gene expression was detected, using an end-point polymerase chain reaction (PCR), not only in the eyestalk ganglia but also in the brain and thoracic ganglia. Quantified using a real-time PCR, Sp-RPCH gene expression levels in the three tissues fluctuated along a cycle of ovarian maturation, with the levels progressively increased from stages I to IV, after which the expression levels decreased (although they remained significantly higher than stage I levels) when the ovary reached the mature stage (stage V). It was demonstrated using a patch clamp analysis that synthetic RPCH was able to evoke a Ca(2+) current in dissociated brain neurons and synthetic RPCH significantly increased the mean oocyte diameter of the ovarian tissues co-cultured with the eyestalk ganglia, brain, or thoracic ganglia; the stimulatory effect of RPCH was absent when the nervous tissues were not included in the ovarian incubation. Animals administrated with RPCH had significantly higher levels of gonad-somatic index, hepatopancreas-somatic index, and vitellogenin gene expression, when compared to control animals receiving a saline injection. The combined results clearly show that RPCH is involved in ovarian maturation in the mud crab; the stimulatory effects of RPCH are likely mediated by its actions on the release from the nervous tissues of factor(s) that directly regulate vitellogenesis in the ovary and hepatopancreas. PMID:26679434

  8. Growth Hormone Promotes Lymphangiogenesis

    PubMed Central

    Banziger-Tobler, Nadja Erika; Halin, Cornelia; Kajiya, Kentaro; Detmar, Michael

    2008-01-01

    The lymphatic system plays an important role in inflammation and cancer progression, although the molecular mechanisms involved are poorly understood. As determined using comparative transcriptional profiling studies of cultured lymphatic endothelial cells versus blood vascular endothelial cells, growth hormone receptor was expressed at much higher levels in lymphatic endothelial cells than in blood vascular endothelial cells. These findings were confirmed by quantitative real-time reverse transcriptase-polymerase chain reaction and Western blot analyses. Growth hormone induced in vitro proliferation, sprouting, tube formation, and migration of lymphatic endothelial cells, and the mitogenic effect was independent of vascular endothelial growth factor receptor-2 or -3 activation. Growth hormone also inhibited serum starvation-induced lymphatic endothelial cell apoptosis. No major alterations of lymphatic vessels were detected in the normal skin of bovine growth hormone-transgenic mice. However, transgenic delivery of growth hormone accelerated lymphatic vessel ingrowth into the granulation tissue of full-thickness skin wounds, and intradermal delivery of growth hormone resulted in enlargement and enhanced proliferation of cutaneous lymphatic vessels in wild-type mice. These results identify growth hormone as a novel lymphangiogenic factor. PMID:18583315

  9. Sex hormone-related and growth hormone-related alopecias.

    PubMed

    Schmeitzel, L P

    1990-11-01

    Canine endocrine dermatoses are characterized by bilateral symmetrical alopecia. Although growth hormone-related and sex hormone-related dermatoses are less common than hypothyroidism and hyperadrenocorticism, they are important causes of hormonal skin disease. Several new syndromes associated with growth and sex hormones recently have been described.

  10. Bioidentical Hormones and Menopause

    MedlinePlus

    ... There are two types of bioidentical hormone products: • Pharmaceutical products. These products have been approved by the ... made products. These are made in a compounding pharmacy (a pharmacy that mixes medications according to a ...

  11. Bioidentical Hormones and Menopause

    MedlinePlus

    ... There are two types of bioidentical hormone products: Pharmaceutical products . These products have been approved by the ... made products. These are made in a compounding pharmacy(a pharmacy that mixes medications according to a ...

  12. Endocrine Glands & Their Hormones

    MedlinePlus

    ... Home » Cancer Registration & Surveillance Modules » Anatomy & Physiology » Endocrine System » Endocrine Glands & Their Hormones Cancer Registration & Surveillance Modules Anatomy & Physiology Intro to the Human Body Body Functions & Life Process Anatomical Terminology Review Quiz ...

  13. Thyroid Hormone Treatment

    MedlinePlus

    ... is to closely replicate normal thyroid functioning. Pure, synthetic thyroxine (T4) works in the same way as ... needing thyroid hormone replacement (see Hypothyroidism brochure ). Pure synthetic thyroxine (T4), taken once daily by mouth, successfully ...

  14. [Advances in hormonal contraception].

    PubMed

    Villanueva Egan, Luis Alberto; Pichardo Cuevas, Mauricio

    2007-01-01

    This review provides an update regarding newer options in hormonal contraception that include the progestin-releasing intrauterine system, the contraceptive patch and ring, the single rod progestin-releasing implant, extended and emergency oral contraception and recent advances in hormonal male contraception. These methods represent a major advancement in this field, allowing for the development of more acceptable, safety and effective birth control regimens.

  15. Growth Hormone-Releasing Hormone in Diabetes

    PubMed Central

    Fridlyand, Leonid E.; Tamarina, Natalia A.; Schally, Andrew V.; Philipson, Louis H.

    2016-01-01

    Growth hormone-releasing hormone (GHRH) is produced by the hypothalamus and stimulates growth hormone synthesis and release in the anterior pituitary gland. In addition, GHRH is an important regulator of cellular functions in many cells and organs. Expression of GHRH G-Protein Coupled Receptor (GHRHR) has been demonstrated in different peripheral tissues and cell types, including pancreatic islets. Among the peripheral activities, recent studies demonstrate a novel ability of GHRH analogs to increase and preserve insulin secretion by beta-cells in isolated pancreatic islets, which makes them potentially useful for diabetes treatment. This review considers the role of GHRHR in the beta-cell and addresses the unique engineered GHRH agonists and antagonists for treatment of type 2 diabetes mellitus. We discuss the similarity of signaling pathways activated by GHRHR in pituitary somatotrophs and in pancreatic beta-cells and possible ways as to how the GHRHR pathway can interact with glucose and other secretagogues to stimulate insulin secretion. We also consider the hypothesis that novel GHRHR agonists can improve glucose metabolism in Type 2 diabetes by preserving the function and survival of pancreatic beta-cells. Wound healing and cardioprotective action with new GHRH agonists suggest that they may prove useful in ameliorating certain diabetic complications. These findings highlight the future potential therapeutic effectiveness of modulators of GHRHR activity for the development of new therapeutic approaches in diabetes and its complications. PMID:27777568

  16. Treatment with thyroid hormone.

    PubMed

    Biondi, Bernadette; Wartofsky, Leonard

    2014-06-01

    Thyroid hormone deficiency can have important repercussions. Treatment with thyroid hormone in replacement doses is essential in patients with hypothyroidism. In this review, we critically discuss the thyroid hormone formulations that are available and approaches to correct replacement therapy with thyroid hormone in primary and central hypothyroidism in different periods of life such as pregnancy, birth, infancy, childhood, and adolescence as well as in adult patients, the elderly, and in patients with comorbidities. Despite the frequent and long term use of l-T4, several studies have documented frequent under- and overtreatment during replacement therapy in hypothyroid patients. We assess the factors determining l-T4 requirements (sex, age, gender, menstrual status, body weight, and lean body mass), the major causes of failure to achieve optimal serum TSH levels in undertreated patients (poor patient compliance, timing of l-T4 administration, interferences with absorption, gastrointestinal diseases, and drugs), and the adverse consequences of unintentional TSH suppression in overtreated patients. Opinions differ regarding the treatment of mild thyroid hormone deficiency, and we examine the recent evidence favoring treatment of this condition. New data suggesting that combined therapy with T3 and T4 could be indicated in some patients with hypothyroidism are assessed, and the indications for TSH suppression with l-T4 in patients with euthyroid multinodular goiter and in those with differentiated thyroid cancer are reviewed. Lastly, we address the potential use of thyroid hormones or their analogs in obese patients and in severe cardiac diseases, dyslipidemia, and nonthyroidal illnesses.

  17. Feeding and Fasting Signals Converge on the LKB1-SIK3 Pathway to Regulate Lipid Metabolism in Drosophila.

    PubMed

    Choi, Sekyu; Lim, Dae-Sik; Chung, Jongkyeong

    2015-05-01

    LKB1 plays important roles in governing energy homeostasis by regulating AMP-activated protein kinase (AMPK) and other AMPK-related kinases, including the salt-inducible kinases (SIKs). However, the roles and regulation of LKB1 in lipid metabolism are poorly understood. Here we show that Drosophila LKB1 mutants display decreased lipid storage and increased gene expression of brummer, the Drosophila homolog of adipose triglyceride lipase (ATGL). These phenotypes are consistent with those of SIK3 mutants and are rescued by expression of constitutively active SIK3 in the fat body, suggesting that SIK3 is a key downstream kinase of LKB1. Using genetic and biochemical analyses, we identify HDAC4, a class IIa histone deacetylase, as a lipolytic target of the LKB1-SIK3 pathway. Interestingly, we found that the LKB1-SIK3-HDAC4 signaling axis is modulated by dietary conditions. In short-term fasting, the adipokinetic hormone (AKH) pathway, related to the mammalian glucagon pathway, inhibits the kinase activity of LKB1 as shown by decreased SIK3 Thr196 phosphorylation, and consequently induces HDAC4 nuclear localization and brummer gene expression. However, under prolonged fasting conditions, AKH-independent signaling decreases the activity of the LKB1-SIK3 pathway to induce lipolytic responses. We also identify that the Drosophila insulin-like peptides (DILPs) pathway, related to mammalian insulin pathway, regulates SIK3 activity in feeding conditions independently of increasing LKB1 kinase activity. Overall, these data suggest that fasting stimuli specifically control the kinase activity of LKB1 and establish the LKB1-SIK3 pathway as a converging point between feeding and fasting signals to control lipid homeostasis in Drosophila.

  18. Feeding and Fasting Signals Converge on the LKB1-SIK3 Pathway to Regulate Lipid Metabolism in Drosophila

    PubMed Central

    Choi, Sekyu; Lim, Dae-Sik; Chung, Jongkyeong

    2015-01-01

    LKB1 plays important roles in governing energy homeostasis by regulating AMP-activated protein kinase (AMPK) and other AMPK-related kinases, including the salt-inducible kinases (SIKs). However, the roles and regulation of LKB1 in lipid metabolism are poorly understood. Here we show that Drosophila LKB1 mutants display decreased lipid storage and increased gene expression of brummer, the Drosophila homolog of adipose triglyceride lipase (ATGL). These phenotypes are consistent with those of SIK3 mutants and are rescued by expression of constitutively active SIK3 in the fat body, suggesting that SIK3 is a key downstream kinase of LKB1. Using genetic and biochemical analyses, we identify HDAC4, a class IIa histone deacetylase, as a lipolytic target of the LKB1-SIK3 pathway. Interestingly, we found that the LKB1-SIK3-HDAC4 signaling axis is modulated by dietary conditions. In short-term fasting, the adipokinetic hormone (AKH) pathway, related to the mammalian glucagon pathway, inhibits the kinase activity of LKB1 as shown by decreased SIK3 Thr196 phosphorylation, and consequently induces HDAC4 nuclear localization and brummer gene expression. However, under prolonged fasting conditions, AKH-independent signaling decreases the activity of the LKB1-SIK3 pathway to induce lipolytic responses. We also identify that the Drosophila insulin-like peptides (DILPs) pathway, related to mammalian insulin pathway, regulates SIK3 activity in feeding conditions independently of increasing LKB1 kinase activity. Overall, these data suggest that fasting stimuli specifically control the kinase activity of LKB1 and establish the LKB1-SIK3 pathway as a converging point between feeding and fasting signals to control lipid homeostasis in Drosophila. PMID:25996931

  19. [Paraneoplastic hormonal syndromes].

    PubMed

    Forga, L; Anda, E; Martínez de Esteban, J P

    2005-01-01

    We can define paraneoplastic syndromes as a combination of effects occurring far from the original location of the tumour and independently from the local repercussion of its metastases. Paraneoplastic hormonal syndromes depend on the secretion of hormonal peptides or their precursors, cytokines and, more rarely, thyroidal hormones and Vitamin D, which act in an endocrine, paracrine or autocrine way. Sometimes, paraneoplastic syndromes can be more serious than the consequences of the primary tumour itself and can precede, develop in parallel, or follow the manifestations of this tumour. It is important to recognise a paraneoplastic hormonal syndrome for several reasons, amongst which we would draw attention to three: 1) It can lead to the diagnosis of a previously undetected, underlying malign or benign neoplasia; 2) It can dominate the clinical picture and thus lead to errors with respect to the origin and type of primary tumour; and 3) It can follow the clinical course of the underlying tumour and thus be useful for monitoring its evolution. The molecular mechanisms responsible for the development of these syndromes are not well-known, but it is believed that they might be inherent to the mutations responsible for the primary tumour or depend on epigenetic factors such as methylation. In this review, we consider the following paraneoplastic hormonal syndromes: malign hypercalcaemia, hyponatraemia (inappropiate secretion of the antidiuretic hormone), ectopic Cushing's syndrome, ectopic acromegaly, hypoglycaemia due to tumours different from those of the islet cells and paraneoplastic gynaecomastia; we make a brief final reference to other hormones (calcitonin, somatostatin, and VIP). PMID:16155618

  20. Plant peptide hormone signalling.

    PubMed

    Motomitsu, Ayane; Sawa, Shinichiro; Ishida, Takashi

    2015-01-01

    The ligand-receptor-based cell-to-cell communication system is one of the most important molecular bases for the establishment of complex multicellular organisms. Plants have evolved highly complex intercellular communication systems. Historical studies have identified several molecules, designated phytohormones, that function in these processes. Recent advances in molecular biological analyses have identified phytohormone receptors and signalling mediators, and have led to the discovery of numerous peptide-based signalling molecules. Subsequent analyses have revealed the involvement in and contribution of these peptides to multiple aspects of the plant life cycle, including development and environmental responses, similar to the functions of canonical phytohormones. On the basis of this knowledge, the view that these peptide hormones are pivotal regulators in plants is becoming increasingly accepted. Peptide hormones are transcribed from the genome and translated into peptides. However, these peptides generally undergo further post-translational modifications to enable them to exert their function. Peptide hormones are expressed in and secreted from specific cells or tissues. Apoplastic peptides are perceived by specialized receptors that are located at the surface of target cells. Peptide hormone-receptor complexes activate intracellular signalling through downstream molecules, including kinases and transcription factors, which then trigger cellular events. In this chapter we provide a comprehensive summary of the biological functions of peptide hormones, focusing on how they mature and the ways in which they modulate plant functions.

  1. Reproductive hormones and bone.

    PubMed

    Nicks, Kristy M; Fowler, Tristan W; Gaddy, Dana

    2010-06-01

    Hypothalamic gonadotropin-releasing hormone (GnRH) stimulates secretion of pituitary luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which directly regulate ovarian function. Pituitary FSH can modulate osteoclast development, and thereby influence bone turnover. Pituitary oxytocin and prolactin effects on the skeleton are not merely limited to pregnancy and lactation; oxytocin stimulates osteoblastogenesis and bone formation, whereas prolactin exerts skeletal effects in an age-dependent manner. Cyclic levels of inhibins and estrogen suppress FSH and LH, respectively, and also suppress bone turnover via their suppressive effects on osteoblast and osteoclast differentiation. However, continuous exposure to inhibins or estrogen/androgens is anabolic for the skeleton in intact animals and protects against gonadectomy-induced bone loss. Alterations of one hormone in the hypothalamic-pituitary-gonadal (HPG) axis influence other bone-active hormones in the entire feedback loop in the axis. Thus, we propose that the action of the HPG axis should be extended to include its combined effects on the skeleton, thus creating the HPG skeletal (HPGS) axis.

  2. Plant peptide hormone signalling.

    PubMed

    Motomitsu, Ayane; Sawa, Shinichiro; Ishida, Takashi

    2015-01-01

    The ligand-receptor-based cell-to-cell communication system is one of the most important molecular bases for the establishment of complex multicellular organisms. Plants have evolved highly complex intercellular communication systems. Historical studies have identified several molecules, designated phytohormones, that function in these processes. Recent advances in molecular biological analyses have identified phytohormone receptors and signalling mediators, and have led to the discovery of numerous peptide-based signalling molecules. Subsequent analyses have revealed the involvement in and contribution of these peptides to multiple aspects of the plant life cycle, including development and environmental responses, similar to the functions of canonical phytohormones. On the basis of this knowledge, the view that these peptide hormones are pivotal regulators in plants is becoming increasingly accepted. Peptide hormones are transcribed from the genome and translated into peptides. However, these peptides generally undergo further post-translational modifications to enable them to exert their function. Peptide hormones are expressed in and secreted from specific cells or tissues. Apoplastic peptides are perceived by specialized receptors that are located at the surface of target cells. Peptide hormone-receptor complexes activate intracellular signalling through downstream molecules, including kinases and transcription factors, which then trigger cellular events. In this chapter we provide a comprehensive summary of the biological functions of peptide hormones, focusing on how they mature and the ways in which they modulate plant functions. PMID:26374891

  3. Hormonal control of euryhalinity

    USGS Publications Warehouse

    Takei, Yoshio; McCormick, Stephen D.; McCormick, Stephen D.; Farrell, Anthony Peter; Brauner, Colin J.

    2013-01-01

    Hormones play a critical role in maintaining body fluid balance in euryhaline fishes during changes in environmental salinity. The neuroendocrine axis senses osmotic and ionic changes, then signals and coordinates tissue-specific responses to regulate water and ion fluxes. Rapid-acting hormones, e.g. angiotensins, cope with immediate challenges by controlling drinking rate and the activity of ion transporters in the gill, gut, and kidney. Slow-acting hormones, e.g. prolactin and growth hormone/insulin-like growth factor-1, reorganize the body for long-term acclimation by altering the abundance of ion transporters and through cell proliferation and differentiation of ionocytes and other osmoregulatory cells. Euryhaline species exist in all groups of fish, including cyclostomes, and cartilaginous and teleost fishes. The diverse strategies for responding to changes in salinity have led to differential regulation and tissue-specific effects of hormones. Combining traditional physiological approaches with genomic, transcriptomic, and proteomic analyses will elucidate the patterns and diversity of the endocrine control of euryhalinity.

  4. Thyroid hormone resistance.

    PubMed

    Olateju, Tolulope O; Vanderpump, Mark P J

    2006-11-01

    Resistance to thyroid hormone (RTH) is a rare autosomal dominant inherited syndrome of reduced end-organ responsiveness to thyroid hormone. Patients with RTH have elevated serum free thyroxine (FT4) and free triiodothyronine (FT3) concentrations and normal or slightly elevated serum thyroid stimulating hormone (TSH) level. Despite a variable clinical presentation, the common characteristic clinical features are goitre but an absence of the usual symptoms and metabolic consequences of thyroid hormone excess. Patients with RTH can be classified on clinical grounds alone into either generalized resistance (GRTH), pituitary resistance (PRTH) or combined. Mutations in the thyroid hormone receptor (TR) beta gene are responsible for RTH and 122 different mutations have now been identified belonging to 300 families. With the exception of one family found to have complete deletion of the TRbeta gene, all others have been demonstrated to have minor alterations at the DNA level. The differential diagnosis includes a TSH-secreting pituitary adenoma and the presence of endogenous antibodies directed against thyroxine (T4) and triiodothyronine (T3). Failure to differentiate RTH from primary thyrotoxicosis has resulted in the inappropriate treatment of nearly one-third of patients. Although occasionally desirable, no specific treatment is available for RTH; however, the diagnosis allows appropriate genetic counselling. PMID:17132274

  5. [Hormones and hair growth].

    PubMed

    Trüeb, R M

    2010-06-01

    With respect to the relationship between hormones and hair growth, the role of androgens for androgenetic alopecia (AGA) and hirsutism is best acknowledged. Accordingly, therapeutic strategies that intervene in androgen metabolism have been successfully developed for treatment of these conditions. Clinical observations of hair conditions involving hormones beyond the androgen horizon have determined their role in regulation of hair growth: estrogens, prolactin, thyroid hormone, cortisone, growth hormone (GH), and melatonin. Primary GH resistance is characterized by thin hair, while acromegaly may cause hypertrichosis. Hyperprolactinemia may cause hair loss and hirsutism. Partial synchronization of the hair cycle in anagen during late pregnancy points to an estrogen effect, while aromatase inhibitors cause hair loss. Hair loss in a causal relationship to thyroid disorders is well documented. In contrast to AGA, senescent alopecia affects the hair in a diffuse manner. The question arises, whether the hypothesis that a causal relationship exists between the age-related reduction of circulating hormones and organ function also applies to hair and the aging of hair.

  6. Hormonal therapy for epilepsy.

    PubMed

    Stevens, Scott J; Harden, Cynthia L

    2011-08-01

    In 2011, there are greater than 20 antiepileptic medications available. These medications work by modulating neuronal excitability. Reproductive hormones have been found to have a role in the pathogenesis and treatment of seizures by also altering neuronal excitability, especially in women with catamenial epilepsy. The female reproductive hormones have in general opposing effects on neuronal excitability; estrogens generally impart a proconvulsant neurophysiologic tone, whereas the progestogens have anticonvulsant effects. It follows then that fluctuations in the levels of serum progesterone and estrogen throughout a normal reproductive cycle bring about an increased or decreased risk of seizure occurrence based upon the serum estradiol/progesterone ratio. Therefore, using progesterone, its metabolite allopregnanolone, or other hormonal therapies have been explored in the treatment of patients with epilepsy. PMID:21451944

  7. Bioidentical hormone therapy.

    PubMed

    Files, Julia A; Ko, Marcia G; Pruthi, Sandhya

    2011-07-01

    The change in hormonal milieu associated with perimenopause and menopause can lead to a variety of symptoms that can affect a woman's quality of life. Postmenopausal hormone therapy (HT) is an effective, well-tolerated treatment for these symptoms. However, combined HT consisting of conjugated equine estrogen and medroxyprogesterone acetate has been associated with an increased number of health risks when compared with conjugated equine estrogen alone or placebo. As a result, some women are turning to alternative hormonal formulations known as compounded bioidentical HT because they perceive them to be a safer alternative. This article defines compounded bioidentical HT and explores the similarities and differences between it and US Food and Drug Administration-approved HT. We will examine the major claims made by proponents of compounded bioidentical HT and recommend strategies for management of patients who request bioidentical HT from physicians.

  8. Male hormonal contraception.

    PubMed

    Nieschlag, E

    2010-01-01

    The principle of hormonal male contraception based on suppression of gonadotropins and spermatogenesis has been established over the last three decades. All hormonal male contraceptives use testosterone, but only in East Asian men can testosterone alone suppress spermatogenesis to a level compatible with contraceptive protection. In Caucasians, additional agents are required of which progestins are favored. Current clinical trials concentrate on testosterone combined with norethisterone, desogestrel, etonogestrel, DMPA, or nestorone. The first randomized, placebo-controlled clinical trial performed by the pharmaceutical industry demonstrated the effectiveness of a combination of testosterone undecanoate and etonogestrel in suppressing spermatogenesis in volunteers. PMID:20839093

  9. Hormone Therapy for Breast Cancer

    MedlinePlus

    ... Cancers Breast Cancer Screening Research Hormone Therapy for Breast Cancer On This Page What are hormones? How do ... sensitive breast cancer: Adjuvant therapy for early-stage breast cancer : Research has shown that women treated for early- ...

  10. Luteinizing hormone (LH) blood test

    MedlinePlus

    ICSH - blood test; Luteinizing hormone - blood test; Interstitial cell stimulating hormone - blood test ... to temporarily stop medicines that may affect the test results. Be sure to tell your provider about ...

  11. Side Effects of Hormone Therapy

    MedlinePlus

    ... Men Living with Prostate Cancer Side Effects of Hormone Therapy Side Effects Urinary Dysfunction Bowel Dysfunction Erectile Dysfunction Loss of Fertility Side Effects of Hormone Therapy Side Effects of Chemotherapy Side Effects: When ...

  12. Thyroid hormones and bone development.

    PubMed

    Combs, C E; Nicholls, J J; Duncan Bassett, J H; Williams, G R

    2011-03-01

    Thyroid hormones are critical determinants of postnatal skeletal development. Thyroid hormone deficiency or excess in children results in severe abnormalities of linear growth and bone maturation. These clinical observations have been recapitulated in mutant mice and these models have facilitated studies of the mechanisms of thyroid hormone action in the developing skeleton. In this review, we consider in detail the direct and indirect effects of thyroid hormone on bone and the molecular mechanisms involved.

  13. [Hormonal contraception in autoimmpne diseases].

    PubMed

    Matyszkiewicz, Anna; Jach, Robert; Rajtar-Ciosek, Agnieszka; Basta, Tomasz

    2016-01-01

    The onset and the course of autoimmune diseases is influenced among other factors by the sex hormones. Hormonal contraception might affect the course of the autoimmune disease. The paper summarises the manner of save application of hormonal contraception in patients with autoimmune disease. PMID:27526427

  14. Hormonal Control of Fetal Growth.

    ERIC Educational Resources Information Center

    Cooke, Paul S.; Nicoll, Charles S.

    1983-01-01

    Summarizes recent research on hormonal control of fetal growth, presenting data obtained using a new method for studying the area. Effects of endocrine ablations and congenital deficiencies, studies of hormone/receptor levels, in-vitro techniques, hormones implicated in promoting fetal growth, problems with existing methodologies, and growth of…

  15. Thyroid Hormone and Wound Healing

    PubMed Central

    Safer, Joshua D.

    2013-01-01

    Although thyroid hormone is one of the most potent stimulators of growth and metabolic rate, the potential to use thyroid hormone to treat cutaneous pathology has never been subject to rigorous investigation. A number of investigators have demonstrated intriguing therapeutic potential for topical thyroid hormone. Topical T3 has accelerated wound healing and hair growth in rodents. Topical T4 has been used to treat xerosis in humans. It is clear that the use of thyroid hormone to treat cutaneous pathology may be of large consequence and merits further study. This is a review of the literature regarding thyroid hormone action on skin along with skin manifestations of thyroid disease. The paper is intended to provide a context for recent findings of direct thyroid hormone action on cutaneous cells in vitro and in vivo which may portend the use of thyroid hormone to promote wound healing. PMID:23577275

  16. Acne: hormonal concepts and therapy.

    PubMed

    Thiboutot, Diane

    2004-01-01

    Acne vulgaris is the most common skin condition observed in the medical community. Although we know that hormones are important in the development of acne, many questions remain unanswered regarding the mechanisms by which hormones exert their effects. Androgens such as dihydrotestosterone (DHT) and testosterone, the adrenal precursor dehydroepiandrosterone sulfate (DHEAS), estrogens such as estradiol, and other hormones, including growth hormone and insulin-like growth factors (IGFs), may be important in acne. It is not known whether these hormones are taken up from the serum by the sebaceous gland, whether they are produced locally within the gland, or whether a combination of these processes is involved. Finally, the cellular and molecular mechanisms by which these hormones exert their influence on the sebaceous gland have not been fully elucidated. Hormonal therapy is an option in women with acne not responding to conventional treatment or with signs of endocrine abnormalities. PMID:15556729

  17. Hormones in pregnancy

    PubMed Central

    Kumar, Pratap; Magon, Navneet

    2012-01-01

    The endocrinology of human pregnancy involves endocrine and metabolic changes that result from physiological alterations at the boundary between mother and fetus. Progesterone and oestrogen have a great role along with other hormones. The controversies of use of progestogen and others are discussed in this chapter. Progesterone has been shown to stimulate the secretion of Th2 and reduces the secretion of Th1 cytokines which maintains pregnancy. Supportive care in early pregnancy is associated with a significant beneficial effect on pregnancy outcome. Prophylactic hormonal supplementation can be recommended for all assisted reproduction techniques cycles. Preterm labor can be prevented by the use of progestogen. The route of administration plays an important role in the drug's safety and efficacy profile in different trimesters of pregnancy. Thyroid disorders have a great impact on pregnancy outcome and needs to be monitored and treated accordingly. Method of locating review: Pubmed, scopus PMID:23661874

  18. Biosimilar growth hormone.

    PubMed

    Saenger, Paul

    2012-01-01

    As the first wave of biopharmaceuticals is expiring, biosimilars or follow-on -protein products (FOPP's) have emerged. Biosimilar drugs are cheaper than the originator/comparator drug. The regulatory foundation for these products is more advanced and better codified in Europe than in the US. Biosimilar soamtropin has been approved in both the US and Europe. The scientific viability of biosimilar drugs and especially growth hormone has been proven by several rigorously conducted clinical trials. Efficacy and safety data (growth rates, IGF-1 generation) for up to 7 y for pediatric indications measure up favorably to previously approved growth hormones which served as reference comparators. The Obama Administration appears to be committed to establish innovative pathways for the approval of biologics and biosimilars in the US. The cost savings in health care expenditures will be substantial as the global sales of biologics have reached $ 93 billion in 2009.

  19. Peptidomics of Neuropeptidergic Tissues of the Tsetse Fly Glossina morsitans morsitans

    NASA Astrophysics Data System (ADS)

    Caers, Jelle; Boonen, Kurt; Van Den Abbeele, Jan; Van Rompay, Liesbeth; Schoofs, Liliane; Van Hiel, Matthias B.

    2015-12-01

    Neuropeptides and peptide hormones are essential signaling molecules that regulate nearly all physiological processes. The recent release of the tsetse fly genome allowed the construction of a detailed in silico neuropeptide database (International Glossina Genome Consortium, Science 344, 380-386 (2014)), as well as an in-depth mass spectrometric analysis of the most important neuropeptidergic tissues of this medically and economically important insect species. Mass spectrometric confirmation of predicted peptides is a vital step in the functional characterization of neuropeptides, as in vivo peptides can be modified, cleaved, or even mispredicted. Using a nanoscale reversed phase liquid chromatography coupled to a Q Exactive Orbitrap mass spectrometer, we detected 51 putative bioactive neuropeptides encoded by 19 precursors: adipokinetic hormone (AKH) I and II, allatostatin A and B, capability/pyrokinin (capa/PK), corazonin, calcitonin-like diuretic hormone (CT/DH), FMRFamide, hugin, leucokinin, myosuppressin, natalisin, neuropeptide-like precursor (NPLP) 1, orcokinin, pigment dispersing factor (PDF), RYamide, SIFamide, short neuropeptide F (sNPF) and tachykinin. In addition, propeptides, truncated and spacer peptides derived from seven additional precursors were found, and include the precursors of allatostatin C, crustacean cardioactive peptide, corticotropin releasing factor-like diuretic hormone (CRF/DH), ecdysis triggering hormone (ETH), ion transport peptide (ITP), neuropeptide F, and proctolin, respectively. The majority of the identified neuropeptides are present in the central nervous system, with only a limited number of peptides in the corpora cardiaca-corpora allata and midgut. Owing to the large number of identified peptides, this study can be used as a reference for comparative studies in other insects.

  20. Histological organization of the central nervous system and distribution of a gonadotropin-releasing hormone-like peptide in the blue crab, Portunus pelagicus.

    PubMed

    Saetan, Jirawat; Senarai, Thanyaporn; Tamtin, Montakan; Weerachatyanukul, Wattana; Chavadej, Jittipan; Hanna, Peter J; Parhar, Ishwar; Sobhon, Prasert; Sretarugsa, Prapee

    2013-09-01

    We present a detailed histological description of the central nervous system (CNS: brain, subesophageal ganglion, thoracic ganglia, abdominal ganglia) of the blue crab, Portunus pelagicus. Because the presence of gonadotropin-releasing hormone (GnRH) in crustaceans has been disputed, we examine the presence and localization of a GnRH-like peptide in the CNS of the blue crab by using antibodies against lamprey GnRH (lGnRH)-III, octopus GnRH (octGnRH) and tunicate GnRH (tGnRH)-I. These antibodies showed no cross-reactivity with red-pigment-concentrating hormone, adipokinetic hormone, or corazonin. In the brain, strong lGnRH-III immunoreactivity (-ir) was detected in small (7-17 μm diameter) neurons of clusters 8, 9 and 10, in medium-sized (21-36 μm diameter) neurons of clusters 6, 7 and 11 and in the anterior and posterior median protocerebral neuropils, olfactory neuropil, median and lateral antenna I neuropils, tegumentary neuropil and antenna II neuropil. In the subesophageal ganglion, lGnRH-III-ir was detected in medium-sized neurons and in the subesophageal neuropil. In the thoracic and abdominal ganglia, lGnRH-III-ir was detected in medium-sized and small neurons and in the neuropils. OctGnRH-ir was observed in neurons of the same clusters with moderate staining, particularly in the deutocerebrum, whereas tGnRH-I-ir was only detected in medium-sized neurons of cluster 11 in the brain. Thus, anti-lGnRH-III shows greater immunoreactivity in the crab CNS than anti-octGnRH and anti-tGnRH-I. Moreover, our functional bioassay demonstrates that only lGnRH-III has significant stimulatory effects on ovarian growth and maturation. We therefore conclude that, although the true identity of the crab GnRH eludes us, crabs possess a putative GnRH hormone similar to lGnRH-III. The identification and characterization of this molecule is part of our ongoing research.

  1. Thyroid Hormone, Cancer, and Apoptosis.

    PubMed

    Lin, Hung-Yun; Chin, Yu-Tan; Yang, Yu-Chen S H; Lai, Husan-Yu; Wang-Peng, Jacqueline; Liu, Leory F; Tang, Heng-Yuan; Davis, Paul J

    2016-01-01

    Thyroid hormones play important roles in regulating normal metabolism, development, and growth. They also stimulate cancer cell proliferation. Their metabolic and developmental effects and growth effects in normal tissues are mediated primarily by nuclear hormone receptors. A cell surface receptor for the hormone on integrin [alpha]vβ3 is the initiation site for effects on tumor cells. Clinical hypothyroidism may retard cancer growth, and hyperthyroidism was recently linked to the prevalence of certain cancers. Local levels of thyroid hormones are controlled through activation and deactivation of iodothyronine deiodinases in different organs. The relative activities of different deiodinases that exist in tissues or organs also affect the progression and development of specific types of cancers. In this review, the effects of thyroid hormone on signaling pathways in breast, brain, liver, thyroid, and colon cancers are discussed. The importance of nuclear thyroid hormone receptor isoforms and of the hormone receptor on the extracellular domain of integrin [alpha]vβ3 as potential cancer risk factors and therapeutic targets are addressed. We analyze the intracellular signaling pathways activated by thyroid hormones in cancer progression in hyperthyroidism or at physiological concentrations in the euthyroid state. Determining how to utilize the deaminated thyroid hormone analog (tetrac), and its nanoparticulate derivative to reduce risks of cancer progression, enhance therapeutic outcomes, and prevent cancer recurrence is also deliberated. © 2016 American Physiological Society. Compr Physiol 6:1221-1237, 2016. PMID:27347891

  2. Hormone therapy for prostate cancer

    MedlinePlus

    Androgen deprivation therapy; ADT; Androgen suppression therapy; Combined androgen blockade ... Androgens cause prostate cancer cells to grow. Hormone therapy for prostate cancer lowers the effect level of ...

  3. [Hormone replacement therapy--growth hormone, melatonin, DHEA and sex hormones].

    PubMed

    Fukai, Shiho; Akishita, Masahiro

    2009-07-01

    The ability to maintain active and independent living as long as possible is crucial for the healthy longevity. Hormones responsible for some of the manifestations associated with aging are growth hormone, insulin-like growth factor-1 (IGF-1), melatonin, dehydroepiandrosterone (DHEA), sex hormones and thyroid hormones. These hormonal changes are associated with changes in body composition, visceral obesity, muscle weakness, osteoporosis, urinary incontinence, loss of cognitive functioning, reduction in well being, depression, as well as sexual dysfunction. With the prolongation of life expectancy, both men and women today live the latter third life with endocrine deficiencies. Hormone replacement therapy may alleviate the debilitating conditions of secondary partial endocrine deficiencies by preventing or delaying some aspects of aging.

  4. Extrapituitary growth hormone.

    PubMed

    Harvey, S

    2010-12-01

    Pituitary somatotrophs secrete growth hormone (GH) into the bloodstream, to act as a hormone at receptor sites in most, if not all, tissues. These endocrine actions of circulating GH are abolished after pituitary ablation or hypophysectomy, indicating its pituitary source. GH gene expression is, however, not confined to the pituitary gland, as it occurs in neural, immune, reproductive, alimentary, and respiratory tissues and in the integumentary, muscular, skeletal, and cardiovascular systems, in which GH may act locally rather than as an endocrine. These actions are likely to be involved in the proliferation and differentiation of cells and tissues prior to the ontogeny of the pituitary gland. They are also likely to complement the endocrine actions of GH and are likely to maintain them after pituitary senescence and the somatopause. Autocrine or paracrine actions of GH are, however, sometimes mediated through different signaling mechanisms to those mediating its endocrine actions and these may promote oncogenesis. Extrapituitary GH may thus be of physiological and pathophysiological significance.

  5. Sex Hormones and Tendon.

    PubMed

    Hansen, Mette; Kjaer, Michael

    2016-01-01

    The risk of overuse and traumatic tendon and ligament injuries differ between women and men. Part of this gender difference in injury risk is probably explained by sex hormonal differences which are specifically distinct during the sexual maturation in the teenage years and during young adulthood. The effects of the separate sex hormones are not fully elucidated. However, in women, the presence of estrogen in contrast to very low estrogen levels may be beneficial during regular loading of the tissue or during recovering after an injury, as estrogen can enhance tendon collagen synthesis rate. Yet, in active young female athletes, physiological high concentration of estrogen may enhance the risk of injuries due to reduced fibrillar crosslinking and enhanced joint laxity. In men, testosterone can enhance tendon stiffness due to an enhanced tendon collagen turnover and collagen content, but testosterone has also been linked to a reduced responsiveness to relaxin. The present chapter will focus on sex difference in tendon injury risk, tendon morphology and tendon collagen turnover, but also on the specific effects of estrogen and androgens. PMID:27535256

  6. Bovine Parathyroid Hormone: Amino Acid Sequence

    PubMed Central

    Brewer, H. Bryan; Ronan, Rosemary

    1970-01-01

    Bovine parathyroid hormone has been isolated in homogeneous form, and its complete amino acid sequence determined. The bovine hormone is a single chain, 84 amino acids long. It contains amino-terminal alanine, and carboxyl-terminal glutamine. The bovine parathyroid hormone is approximately three times the length of the newly discovered hormone, thyrocalcitonin, whose action is reciprocal to parathyroid hormone. Images PMID:5275384

  7. Hormonal Programming Across the Lifespan

    PubMed Central

    Tobet, Stuart A; Lara, Hernan E; Lucion, Aldo B; Wilson, Melinda E; Recabarren, Sergio E; Paredes, Alfonso H

    2013-01-01

    Hormones influence countless biological processes across the lifespan, and during developmental sensitive periods hormones have the potential to cause permanent tissue-specific alterations in anatomy and physiology. There are numerous critical periods in development wherein different targets are affected. This review outlines the proceedings of the Hormonal Programming in Development session at the US-South American Workshop in Neuroendocrinology in August 2011. Here we discuss how gonadal hormones impact various biological processes within the brain and gonads during early development and describe the changes that take place in the aging female ovary. At the cellular level, hormonal targets in the brain include neurons, glia, or vasculature. On a genomic/epigenomic level, transcription factor signaling and epigenetic changes alter the expression of hormone receptor genes across development and following ischemic brain insult. In addition, organizational hormone exposure alters epigenetic processes in specific brain nuclei and may be a mediator of sexual differentiation of the neonatal brain. During development of the ovary, exposure to excess gonadal hormones leads to polycystic ovarian syndrome (PCOS). Exposure to excess androgens during fetal development also has a profound effect on the development of the male reproductive system. In addition, increased sympathetic nerve activity and stress during early life have been linked to PCOS symptomology in adulthood. Finally, we describe how age-related decreases in fertility are linked to high levels of nerve growth factor (NGF), which enhances sympathetic nerve activity and alters ovarian function. PMID:22700441

  8. Recent advances in hormonal contraception

    PubMed Central

    Li, HW Raymond

    2010-01-01

    This report reviews some of the new studies regarding new hormonal contraceptive formulations (e.g., Yaz, Qlaira®, extended-cycle or continuous combined contraceptives, subcutaneous depot medroxyprogesterone acetate, and ulipristal acetate as an emergency contraceptive). Recent data on the relationship between hormonal contraceptive use and bone health are also reviewed. PMID:21173872

  9. [Do hormones determine our fate?].

    PubMed

    Vermeulen, A

    1994-01-01

    The hormonal system is a communication system between cells and organs. Hence it is not surprising that it influences almost all physiological functions and, at least partially, our behaviour and fate. The sexual phenotype is determined by the sex hormones. Normally, the phenotype is in accordance with gonadal and genetic sex, but occasionally, as a consequence of enzymatic defects in the biosynthesis of sex hormones or of androgen resistance, gonadal and genetic sex are in discordance with the phenotype, the latter determining generally the civil sex and the sex of rearing. Whereas the gender role is generally determined by the sex of rearing and the phenotype, itself under hormonal influence, homo- and transsexuality constitute notorious exceptions to this rule. Although several authors consider homo- and transsexuality to be the consequence of an impairment in androgenic impregnation in the perinatal period, there are at present no convincing arguments for an hormonal origin for either homo- or transsexuality, although such a possibility can't be excluded either. Besides their role in psychosexual behaviour, sex hormones play also a role in our life expectancy. Indeed, although maximal life expectancy of man is genetically determined, a major determinant of individual life expectancy is cardiovascular pathology. The latter is partly responsible for the difference in life expectancy between men and women, cardiovascular mortality increasing rapidly at menopause and being halved by oestrogen replacement therapy. Also atherogenesis as such is, to a large extend, under hormonal control. Indeed insulin resistance and hyperinsulinism, which develop as a corollary of the aging process, is an important cause of atherosclerosis as well as of hypertension. Other hormones also play an important role in our behaviour. We can mention here the role of the thyroid hormones in the physical and mental development of children as well as in the regression of the intellectual

  10. Types of Cancer Treatment: Hormone Therapy

    Cancer.gov

    Describes how hormone therapy slows or stops the growth of breast and prostate cancers that use hormones to grow. Includes information about the types of hormone therapy and side effects that may happen.

  11. Growth hormone stimulation test - series (image)

    MedlinePlus

    The growth hormone (GH) is a protein hormone released from the anterior pituitary gland under the control of the hypothalamus. ... performed on infants and children to identify human growth hormone (hGH) deficiency as a cause of growth retardation. ...

  12. Genetics Home Reference: isolated growth hormone deficiency

    MedlinePlus

    ... Health Conditions isolated growth hormone deficiency isolated growth hormone deficiency Enable Javascript to view the expand/collapse ... PDF Open All Close All Description Isolated growth hormone deficiency is a condition caused by a severe ...

  13. Quo vadis plant hormone analysis?

    PubMed

    Tarkowská, Danuše; Novák, Ondřej; Floková, Kristýna; Tarkowski, Petr; Turečková, Veronika; Grúz, Jiří; Rolčík, Jakub; Strnad, Miroslav

    2014-07-01

    Plant hormones act as chemical messengers in the regulation of myriads of physiological processes that occur in plants. To date, nine groups of plant hormones have been identified and more will probably be discovered. Furthermore, members of each group may participate in the regulation of physiological responses in planta both alone and in concert with members of either the same group or other groups. The ideal way to study biochemical processes involving these signalling molecules is 'hormone profiling', i.e. quantification of not only the hormones themselves, but also their biosynthetic precursors and metabolites in plant tissues. However, this is highly challenging since trace amounts of all of these substances are present in highly complex plant matrices. Here, we review advances, current trends and future perspectives in the analysis of all currently known plant hormones and the associated problems of extracting them from plant tissues and separating them from the numerous potentially interfering compounds.

  14. Growth hormone neurosecretory dysfunction.

    PubMed

    Bercu, B B; Diamond, F B

    1986-08-01

    The basis for understanding clinical disorders in the neuroregulation of GH secretion is derived from the complexity of the CNS-hypothalamic-pituitary axis. Studies in animals and humans demonstrate an anatomic, physiological and pharmacological evidence for neurosecretory control over GH secretion including neurohormones (GRH, somatostatin), neurotransmitters (dopaminergic, adrenergic, cholinergic, serotonergic, histaminergic, GABAergic), and neuropeptides (gut hormones, opioids, CRH, TRH, etc). The observation of a defect in the neuroregulatory control of GH secretion in CNS-irradiated humans and animals led to the hypothesis of a disorder in neurosecretion, GHND, as a cause for short stature. We speculate that in this heterogeneous group of children a disruption in the neurotransmitter-neurohormonal functional pathway could modify secretion ultimately expressed as poor growth velocity and short stature.

  15. Hormonal adaptation to real and simulated microgravity.

    PubMed

    Strollo, F; Strollo, G; More, M; Bollanti, L; Ciarmatori, A; Longo, E; Quintiliani, R; Mambro, A; Mangrossa, N; Ferretti, C

    1998-07-01

    The authors provide an overview of relevant results from endocrine studies in astronauts before, during, and after space flight. The hormonal systems examined are the water-electrolyte regulation, the hypothalamic-pituitary-adrenal axis, the hypothalamic-pituitary gonadal axis, the growth hormone-insulin like growth factor 1-prolactin system, hormones which affect bone turnover, the hypothalamic-pituitary-thyroid axis, and the endocrine pancreas. Hormones studied include renin, aldosterone, vasopressin, atrial natriuretic factor, cortisol, testosterone, lutenizing hormone, prolactin, growth hormone, insulin-like growth factor-1, insulin, glucose, T4, thyroid stimulating hormone, calcitonin, active D3, and parathyroid hormone.

  16. Plant hormone signaling lightens up: integrators of light and hormones.

    PubMed

    Lau, On Sun; Deng, Xing Wang

    2010-10-01

    Light is an important environmental signal that regulates diverse growth and developmental processes in plants. In these light-regulated processes, multiple hormonal pathways are often modulated by light to mediate the developmental changes. Conversely, hormone levels in plants also serve as endogenous cues in influencing light responsiveness. Although interactions between light and hormone signaling pathways have long been observed, recent studies have advanced our understanding by identifying signaling integrators that connect the pathways. These integrators, namely PHYTOCHROME-INTERACTING FACTOR 3 (PIF3), PIF4, PIF3-LIKE 5 (PIL5)/PIF1 and LONG HYPOCOTYL 5 (HY5), are key light signaling components and they link light signals to the signaling of phytohormones, such as gibberellin (GA), abscisic acid (ABA), auxin and cytokinin, in regulating seedling photomorphogenesis and seed germination. This review focuses on these integrators in illustrating how light and hormone interact.

  17. Hormone signaling in plant development.

    PubMed

    Durbak, Amanda; Yao, Hong; McSteen, Paula

    2012-02-01

    Hormone signaling plays diverse and critical roles during plant development. In particular, hormone interactions regulate meristem function and therefore control formation of all organs in the plant. Recent advances have dissected commonalities and differences in the interaction of auxin and cytokinin in the regulation of shoot and root apical meristem function. In addition, brassinosteroid hormones have recently been discovered to regulate root apical meristem size. Further insights have also been made into our understanding of the mechanism of crosstalk among auxin, cytokinin, and strigolactone in axillary meristems.

  18. Gut hormones in tropical malabsorption.

    PubMed Central

    Besterman, H S; Cook, G C; Sarson, D L; Christofides, N D; Bryant, M G; Gregor, M; Bloom, S R

    1979-01-01

    Concentrations of various gut hormones were measured after a test breakfast in eight patients with severe tropical malabsorption and 12 controls. The patients with tropical malabsorption had greatly raised basal plasma motilin and enteroglucagon concentrations, but their postprandial release of both gastric inhibitory polypeptide and insulin was significantly reduced. The pattern of gut hormone release differed from that found in coeliac disease. The measurement of gut hormones, each of which has a specific site and function, thus throws new light on the pathophysiology of tropical malabsorption and may suggest approaches of treatment. PMID:519400

  19. Specific involvement of gonadal hormones in the functional maturation of growth hormone releasing hormone (GHRH) neurons.

    PubMed

    Gouty-Colomer, Laurie-Anne; Méry, Pierre-François; Storme, Emilie; Gavois, Elodie; Robinson, Iain C; Guérineau, Nathalie C; Mollard, Patrice; Desarménien, Michel G

    2010-12-01

    Growth hormone (GH) is the key hormone involved in the regulation of growth and metabolism, two functions that are highly modulated during infancy. GH secretion, controlled mainly by GH releasing hormone (GHRH), has a characteristic pattern during postnatal development that results in peaks of blood concentration at birth and puberty. A detailed knowledge of the electrophysiology of the GHRH neurons is necessary to understand the mechanisms regulating postnatal GH secretion. Here, we describe the unique postnatal development of the electrophysiological properties of GHRH neurons and their regulation by gonadal hormones. Using GHRH-eGFP mice, we demonstrate that already at birth, GHRH neurons receive numerous synaptic inputs and fire large and fast action potentials (APs), consistent with effective GH secretion. Concomitant with the GH secretion peak occurring at puberty, these neurons display modifications of synaptic input properties, decrease in AP duration, and increase in a transient voltage-dependant potassium current. Furthermore, the modulation of both the AP duration and voltage-dependent potassium current are specifically controlled by gonadal hormones because gonadectomy prevented the maturation of these active properties and hormonal treatment restored it. Thus, GHRH neurons undergo specific developmental modulations of their electrical properties over the first six postnatal weeks, in accordance with hormonal demand. Our results highlight the importance of the interaction between the somatotrope and gonadotrope axes during the establishment of adapted neuroendocrine functions.

  20. Hormonal Regulation of Leaf Abscission

    PubMed Central

    Jacobs, William P.

    1968-01-01

    A review is given of the progress made during the last 6 years in elucidating the nature, locus of action, and transport properties of the endogenous hormones that control leaf abscission. PMID:16657014

  1. Menopausal Hormone Therapy and Cancer

    MedlinePlus

    ... both combination and estrogen-alone hormone use made mammography less effective for the early detection of breast ... such as a reduction in the use of mammography, may also have contributed to this decline ( 15 ). ...

  2. Sex Hormones and Immune Dimorphism

    PubMed Central

    Bhatia, Aruna; Sekhon, Harmandeep Kaur; Kaur, Gurpreet

    2014-01-01

    The functioning of the immune system of the body is regulated by many factors. The abnormal regulation of the immune system may result in some pathological conditions. Sex hormones of reproductive system are one of the major factors that regulate immune system due to the presence of hormone receptors on immune cells. The interaction of sex hormones and immune cells through the receptors on these cells effect the release of cytokines which determines the proliferation, differentiation, and maturation of different types of immunocytes and as a result the outcome of inflammatory or autoimmune diseases. The different regulations of sex hormones in both sexes result in immune dimorphism. In this review article the mechanism of regulation of immune system in different sexes and its impact are discussed. PMID:25478584

  3. [Hormone therapy through changing times].

    PubMed

    Reuter, Miriam; Fassnacht, Martin

    2016-02-01

    Despite several studies in the last years, only women with menopausal symptoms who desire therapy are treated. There is still no recommendation for menopausale hormone therapy for primary prevention of diseases such as coronary artery disease, osteoporosis or depression. The risk of thrombosis, pulmonary embolism and stroke is elevated especially for elderly women with oral hormone therapy. Benefits may exceed risks in younger, early-menopausal women, for whom hormone therapy may be prescribed more liberally. Systemic hormone therapy is for vasomotor symptoms, local therapy for the genitourinary syndrome of menopause. Choice of formulation depends on the individual risk due to symptoms and favours of the patients. With moderate to high cardiovascular risk profile, a transdermal route of estrogen application - in women with an intact uterus in combination with micronized progesterone - seems to be the best option.

  4. Hormone Therapy for Prostate Cancer

    MedlinePlus

    ... agonists , which are sometimes called LHRH analogs, are synthetic proteins that are structurally similar to LHRH and ... gland to stop producing luteinizing hormone, which prevents testosterone from being produced. Treatment with an LHRH agonist ...

  5. Thyroid Hormone and Vascular Remodeling.

    PubMed

    Ichiki, Toshihiro

    2016-01-01

    Both hyperthyroidism and hypothyroidism affect the cardiovascular system. Hypothyroidism is known to be associated with enhanced atherosclerosis and ischemic heart diseases. The accelerated atherosclerosis in the hypothyroid state has been traditionally ascribed to atherogenic lipid profile, diastolic hypertension, and impaired endothelial function. However, recent studies indicate that thyroid hormone has direct anti-atherosclerotic effects, such as production of nitric oxide and suppression of smooth muscle cell proliferation. These data suggest that thyroid hormone inhibits atherogenesis through direct effects on the vasculature as well as modification of risk factors for atherosclerosis. This review summarizes the basic and clinical studies on the role of thyroid hormone in vascular remodeling. The possible application of thyroid hormone mimetics to the therapy of hypercholesterolemia and atherosclerosis is also discussed. PMID:26558400

  6. Network Identification of Hormonal Regulation

    PubMed Central

    Vis, Daniel J.; Westerhuis, Johan A.; Hoefsloot, Huub C. J.; Roelfsema, Ferdinand; van der Greef, Jan

    2014-01-01

    Relations among hormone serum concentrations are complex and depend on various factors, including gender, age, body mass index, diurnal rhythms and secretion stochastics. Therefore, endocrine deviations from healthy homeostasis are not easily detected or understood. A generic method is presented for detecting regulatory relations between hormones. This is demonstrated with a cohort of obese women, who underwent blood sampling at 10 minute intervals for 24-hours. The cohort was treated with bromocriptine in an attempt to clarify how hormone relations change by treatment. The detected regulatory relations are summarized in a network graph and treatment-induced changes in the relations are determined. The proposed method identifies many relations, including well-known ones. Ultimately, the method provides ways to improve the description and understanding of normal hormonal relations and deviations caused by disease or treatment. PMID:24852517

  7. Ghrelin: much more than a hunger hormone

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Ghrelin is a multifaceted gut hormone that activates its receptor, growth hormone secretagogue receptor (GHS-R). Ghrelin's hallmark functions are its stimulatory effects on growth hormone release, food intake and fat deposition. Ghrelin is famously known as the 'hunger hormone'. However, ample recen...

  8. [Hormonal disruptors and farm animals].

    PubMed

    van Os, J L

    1998-01-01

    A number of man made environmental contaminants displays a weak hormonal, usually oestrogenic, activity. Currently such contaminants are termed hormone disruptors, a terminology that also includes natural compounds with hormonal activity, such as phyto and fungal oestrogens. Fertility and morphological defects in wildlife are related to high exposure to man made hormone disruptors. The potential threat of such exposure for human reproductive health is widely discussed. A possible decline in sperm counts in men is one of the subjects related to such environmental factors. There are no firm indications for this threat. Additional research is needed, however, for a more complete assessment. Farm animals so far played a minor role in the discussion. Therefore, in a study published elsewhere, long term trends in sperm counts of Dutch Dairy Bulls have been evaluated (27). No decline was found in 75,238 ejaculates collected between 1977 and 1996 from 2,314 bulls of the centre for artificial insemination (AI) NOORDWEST. Results of this study, published elsewhere, formed the reason to broader go into the relation between hormone disruptors and farm animals, observed effects of phyto-oestrogens in such animal and the role these animals could play in further research. PMID:9537066

  9. Electrochemical biosensors for hormone analyses.

    PubMed

    Bahadır, Elif Burcu; Sezgintürk, Mustafa Kemal

    2015-06-15

    Electrochemical biosensors have a unique place in determination of hormones due to simplicity, sensitivity, portability and ease of operation. Unlike chromatographic techniques, electrochemical techniques used do not require pre-treatment. Electrochemical biosensors are based on amperometric, potentiometric, impedimetric, and conductometric principle. Amperometric technique is a commonly used one. Although electrochemical biosensors offer a great selectivity and sensitivity for early clinical analysis, the poor reproducible results, difficult regeneration steps remain primary challenges to the commercialization of these biosensors. This review summarizes electrochemical (amperometric, potentiometric, impedimetric and conductometric) biosensors for hormone detection for the first time in the literature. After a brief description of the hormones, the immobilization steps and analytical performance of these biosensors are summarized. Linear ranges, LODs, reproducibilities, regenerations of developed biosensors are compared. Future outlooks in this area are also discussed.

  10. Pathology of growth hormone excess.

    PubMed

    Kovacs, K

    1988-09-01

    This paper briefly reviews the pathology of growth hormone excess. Prolonged oversecretion of growth hormone is associated with elevated serum growth hormone as well as somatomedian C levels and the clinical signs and symptoms of acromegaly or gigantism. Morphologic studies, including immunohistochemistry and electron microscopy, revealed that several distinct morphologic lesions can be present in the pituitary gland of patients with acromegaly or gigantism. Although substantial progress has been achieved during the last two decades, more work is required to correlate the morphologic features of adenoma cells with their biologic behavior. We feel that the future can be viewed with optimism and further exciting results can be expected by the interaction of pathologists, clinical endocrinologists and basic scientists. PMID:3070506

  11. Growth Hormone and Cerebral Amyloidosis.

    PubMed

    Benvenga, S; Guarneri, F

    2016-08-01

    Great interest has recently been focused on a paper reporting characteristic deposits of amyloid-β protein associated with Alzheimer's disease in brains of adults who died of Creutzfeldt-Jakob disease. As they had contracted such disease after treatment with prion-contaminated human growth hormone extracted from cadaver-derived pituitaries, the authors have suggested that interhuman transmission of Alzheimer's disease had occurred. Our previous research led us to find that amyloid-forming peptides share amino acid sequence homology, summarized by a motif. Here, we probed the amino acid sequence of human growth hormone for such a motif, and found that 2 segments fit the motif and are potentially amyloid-forming. This finding was confirmed by Aggrescan, another well-known software for the prediction of amyloidogenic peptides. Our results, taken together with data from the literature that are missing in the aforementioned paper and associated commentaries, minimize the contagious nature of the iatrogenically-acquired coexistence of Creutzfeldt-Jakob disease and Alzheimer's disease. In particular, the above mentioned paper misses literature data on intratumoral amyloidosis in growth hormone- and prolactin-secreting adenomas, tumors relatively frequent in adults, which are often silent. It cannot be excluded that some pituitaries used to extract growth hormone contained clinically silent microadenomas, a fraction of which containing amyloid deposits, and patients might had received a fraction of growth hormone (with or without prolactin) that already was an amyloid seed. The intrinsic amyloidogenicity of growth hormone, in the presence of contaminating prion protein (and perhaps prolactin as well) and amyloid-β contained in some cadavers' pituitaries, may have led to the observed co-occurring of Creutzfeldt-Jakob disease and Alzheimer's disease. PMID:27214308

  12. Advances in male hormonal contraception.

    PubMed

    Costantino, Antonietta; Gava, Giulia; Berra, Marta; Meriggiola Maria, Cristina

    2014-11-01

    Contraception is a basic human right for its role on health, quality of life and wellbeing of the woman and of the society as a whole. Since the introduction of female hormonal contraception the responsibility of family planning has always been with women. Currently there are only a few contraceptive methods available for men, but recently, men have become more interested in supporting their partners actively. Over the last few decades different trials have been performed providing important advances in the development of a safe and effective hormonal contraceptive for men. This paper summarizes some of the most recent trials. PMID:25673544

  13. Hormonal Effects on Nodular GAVE

    PubMed Central

    Brijbassie, Alan; Osaimi, Abdullah Al; Powell, Steven M

    2013-01-01

    Gastric antral vascular ectasia (GAVE) and its nodular antral gastropathy (NAG) variant is a unique lesion associated with hypergastrinemic hormonal alterations that may be compounded by concurrent proton pump inhibitor (PPI) therapy. The use of octreotide as a somatostatin analogue and its role in the down regulation of variousenteric hormones has been well documented however its use in the management of NAG has not been widely reported. We herein present a case where octreotide induced gastrin down-regulation as well as PPI cessation facilitated NAG resolution.

  14. Advances in male hormonal contraception

    PubMed Central

    Antonietta, Costantino; Giulia, Gava; Marta, Berra; Cristina, Meriggiola Maria

    2014-01-01

    Contraception is a basic human right for its role on health, quality of life and wellbeing of the woman and of the society as a whole. Since the introduction of female hormonal contraception the responsibility of family planning has always been with women. Currently there are only a few contraceptive methods available for men, but recently, men have become more interested in supporting their partners actively. Over the last few decades different trials have been performed providing important advances in the development of a safe and effective hormonal contraceptive for men. This paper summarizes some of the most recent trials. PMID:25673544

  15. [Corticosteroid hormones and the brain].

    PubMed

    Le Moal, M; Vallée, M; Maccari, S; Mayo, W; Montaron, M F; Piazza, P V; Abrous, N

    1999-01-01

    The anatomical and functional links between the hormone stress axis and the cortico-limbic brain regions which integrate emotion and motivation are well documented. It is important, considering the consequences of stress on the brain, to take into account the regulatory buffer capacities of the personality-cognitive processes. Another point of interest is evaluation of the long term effects of repeated life events on chronic environmental pressures which induce brain negative feedback defects and, subsequently, insidious cellular changes in regions such as the hippocampus that lead to memory or adaptive impairments. An example is provided by perinatal stress that induces, later in life, both hormonal and cognitive deleterious changes. PMID:10542958

  16. Hormonal changes in headache patients.

    PubMed

    Elwan, O; Abdella, M; el Bayad, A B; Hamdy, S

    1991-11-01

    Seventy-three patients with headache underwent serum and cerebrospinal fluid (CSF) radioimmunoassays of follicle-stimulating hormone (FSH), luteinizing hormone (LH), cortisol and prolactin. Serum FSH showed significant increases in all headache patients while serum LH increased only in females. Such a rise of serum FSH and LH is attributed to disturbances of the sleep-wake cycle. On the other hand, serum cortisol was significantly decreased in the male headache patients, probably due to altered circadian rhythm. Serum prolactin remained within normal limits. CSF prolactin, FSH and LH showed detectable levels in all headache sufferers compared to undetectable levels in control subjects, while CSF cortisol was significantly reduced.

  17. The 'Love Hormone' May Quiet Tinnitus

    MedlinePlus

    ... medlineplus.gov/news/fullstory_161110.html The 'Love Hormone' May Quiet Tinnitus Small, preliminary study suggests oxytocin ... tinnitus -- may find some relief by spraying the hormone oxytocin in their nose, a small initial study ...

  18. Growth Hormone: Use and Abuse

    MedlinePlus

    ... than children of the same age), such as chronic kidney disease, Turner syndrome, and Prader-Willi syndrome In adults, GH is used to treat • Growth hormone deficiency • Muscle wasting (loss of muscle tissue) from HIV • Short bowel ...

  19. Aetiology of growth hormone deficiency.

    PubMed Central

    Herber, S M; Kay, R

    1987-01-01

    A retrospective analysis was performed in an attempt to identify perinatal risk factors for the development of growth hormone deficiency. More of the affected children were boys, and their birth weights were significantly lower than those of the national average; there were also considerably more preterm and post-term deliveries among boys. PMID:3632025

  20. Anabolic steroids and growth hormone.

    PubMed

    Haupt, H A

    1993-01-01

    Athletes are generally well educated regarding substances that they may use as ergogenic aids. This includes anabolic steroids and growth hormone. Fortunately, the abuse of growth hormone is limited by its cost and the fact that anabolic steroids are simply more enticing to the athlete. There are, however, significant potential adverse effects regarding its use that can be best understood by studying known growth hormone excess, as demonstrated in the acromegalic syndrome. Many athletes are unfamiliar with this syndrome and education of the potential consequences of growth hormone excess is important in counseling athletes considering its use. While athletes contemplating the use of anabolic steroids may correctly perceive their risks for significant physiologic effects to be small if they use the steroids for brief periods of time, many of these same athletes are unaware of the potential for habituation to the use of anabolic steroids. The result may be incessant use of steroids by an athlete who previously considered only short-term use. As we see athletes taking anabolic steroids for more prolonged periods, we are likely to see more severe medical consequences. Those who eventually do discontinue the steroids are dismayed to find that the improvements made with the steroids generally disappear and they have little to show for hours or even years of intense training beyond the psychological scars inherent with steroid use. Counseling of these athletes should focus on the potential adverse psychological consequences of anabolic steroid use and the significant risk for habituation.

  1. "Sex Hormones" in Secondary School Biology Textbooks

    ERIC Educational Resources Information Center

    Nehm, Ross H.; Young, Rebecca

    2008-01-01

    This study explores the extent to which the term "sex hormone" is used in science textbooks, and whether the use of the term "sex hormone" is associated with pre-empirical concepts of sex dualism, in particular the misconceptions that these so-called "sex hormones" are sex specific and restricted to sex-related physiological functioning. We found…

  2. Hormonal treatment of acne vulgaris: an update

    PubMed Central

    Elsaie, Mohamed L

    2016-01-01

    Acne vulgaris is a common skin condition associated with multiple factors. Although mostly presenting alone, it can likewise present with features of hyperandrogenism and hormonal discrepancies. Of note, hormonal therapies are indicated in severe, resistant-to-treatment cases and in those with monthly flare-ups and when standard therapeutic options are inappropriate. This article serves as an update to hormonal pathogenesis of acne, discusses the basics of endocrinal evaluation for patients with suspected hormonal acne, and provides an overview of the current hormonal treatment options in women. PMID:27621661

  3. Hormonal treatment of acne vulgaris: an update

    PubMed Central

    Elsaie, Mohamed L

    2016-01-01

    Acne vulgaris is a common skin condition associated with multiple factors. Although mostly presenting alone, it can likewise present with features of hyperandrogenism and hormonal discrepancies. Of note, hormonal therapies are indicated in severe, resistant-to-treatment cases and in those with monthly flare-ups and when standard therapeutic options are inappropriate. This article serves as an update to hormonal pathogenesis of acne, discusses the basics of endocrinal evaluation for patients with suspected hormonal acne, and provides an overview of the current hormonal treatment options in women.

  4. Hormonal treatment of acne vulgaris: an update.

    PubMed

    Elsaie, Mohamed L

    2016-01-01

    Acne vulgaris is a common skin condition associated with multiple factors. Although mostly presenting alone, it can likewise present with features of hyperandrogenism and hormonal discrepancies. Of note, hormonal therapies are indicated in severe, resistant-to-treatment cases and in those with monthly flare-ups and when standard therapeutic options are inappropriate. This article serves as an update to hormonal pathogenesis of acne, discusses the basics of endocrinal evaluation for patients with suspected hormonal acne, and provides an overview of the current hormonal treatment options in women. PMID:27621661

  5. Parathyroid hormone - Secretion and metabolism in vivo.

    NASA Technical Reports Server (NTRS)

    Habener, J. F.; Powell, D.; Murray, T. M.; Mayer, G. P.; Potts, J. T., Jr.

    1971-01-01

    Gel filtration and radioimmunoassay were used to determine the molecular size and immunochemical reactivity of parathyroid hormone present in gland extracts, in the general peripheral circulation, and in parathyroid effluent blood from patients with hyperparathyroidism, as well as from calves and from cattle. It was found that parathyroid hormone secreted from the parathyroids in man and cattle is at least as large as the molecule extracted from normal bovine glands. However, once secreted into the circulation the hormone is cleaved, and one or more fragments, immunologically, dissimilar to the originally secreted hormone, constitute the dominant form of circulating immunoreactive hormone.

  6. Growth hormone in musculoskeletal pain states.

    PubMed

    Bennett, Robert

    2004-08-01

    Growth hormone is essential for normal linear growth and the attainment of an adult mature height. It also plays an important role in cartilage growth and the attainment of normal bone mass. There is only one rheumatic disorder, namely acromegaly, in which abnormalities of growth hormone production play a major etiologic role. However, there is increasing appreciation that suboptimal growth hormone secretion, leading to a state of adult growth hormone deficiency, may occur in the setting of chronic inflammatory disease, chronic corticosteroid use, and fibromyalgia. Therefore, the evaluation and effective management of growth hormone oversecretion and undersecretion is relevant to practicing rheumatologists. PMID:15251074

  7. Developing a model of plant hormone interactions

    PubMed Central

    Wang, Yu Hua

    2011-01-01

    Plant growth and development is influenced by mutual interactions among plant hormones. The five classical plant hormones are auxins, cytokinins, gibberellins, abscisic acid and ethylene. They are small diffusible molecules that easily penetrate between cells. In addition, newer classes of plant hormones have been identified such as brassinosteroids, jasmonic acid, salicylic acid and various small proteins or peptides. These hormones also play important roles in the regulation of plant growth and development. This review begins with a brief summary of the current findings on plant hormones. Based on this knowledge, a conceptual model about interactions among plant hormones is built so as to link and develop an understanding of the diverse functions of different plant hormones as a whole in plants. PMID:21406974

  8. Ovarian hormones and drug abuse.

    PubMed

    Moran-Santa Maria, Megan M; Flanagan, Julianne; Brady, Kathleen

    2014-11-01

    There are significant gender differences in course, symptomology, and treatment of substance use disorders. In general data from clinical and preclinical studies of substance use disorders suggest that women are more vulnerable than men to the deleterious consequences of drug use at every phase of the addiction process. In addition data from epidemiologic studies suggest that the gender gap in the prevalence of substance use is narrowing particularly among adolescence. Therefore, understanding the role of estrogen and progesterone in mediating responses to drugs of abuse is of critical importance to women's health. In this review we will discuss findings from clinical and preclinical studies of (1) reproductive cycle phase; (2) endogenous ovarian hormones; and (3) hormone replacement on responses to stimulants, nicotine, alcohol, opioids, and marijuana. In addition, we discuss data from recent studies that have advanced our understanding of the neurobiologic mechanisms that interact with estrogen and progesterone to mediate drug-seeking behavior.

  9. Modelling hormonal response and development☆

    PubMed Central

    Voß, Ute; Bishopp, Anthony; Farcot, Etienne; Bennett, Malcolm J.

    2014-01-01

    As our knowledge of the complexity of hormone homeostasis, transport, perception, and response increases, and their outputs become less intuitive, modelling is set to become more important. Initial modelling efforts have focused on hormone transport and response pathways. However, we now need to move beyond the network scales and use multicellular and multiscale modelling approaches to predict emergent properties at different scales. Here we review some examples where such approaches have been successful, for example, auxin–cytokinin crosstalk regulating root vascular development or a study of lateral root emergence where an iterative cycle of modelling and experiments lead to the identification of an overlooked role for PIN3. Finally, we discuss some of the remaining biological and technical challenges. PMID:24630843

  10. A Simulated Growth Hormone Analysis

    NASA Astrophysics Data System (ADS)

    Harris, Mary

    1996-08-01

    Growth hormone is a drug that is sometimes abused by amateur or professional athletes for performance-enhancement. This laboratory is a semimicroscale simulation analysis of a sample of "urine" to detect proteins of two very different molecular weights. Gel filtration uses a 10 mL disposable pipette packed with Sephadex. Students analyze the fractions from the filtration by comparing colors of the Brilliant Blue Coomassie Dye as it interacts with the proteins in the sample to a standard set of known concentration of protein with the dye. The simulated analysis of growth hormone is intended to be included in a unit on organic chemistry or in the second year of high school chemistry.

  11. Parathyroid hormone therapy for hypoparathyroidism.

    PubMed

    Cusano, Natalie E; Rubin, Mishaela R; Bilezikian, John P

    2015-01-01

    Hypoparathyroidism is a disease characterized by hypocalcemia and insufficient parathyroid hormone (PTH). It is a rare disorder that has been given an orphan disease designation in the United States and European Union. Hypoparathyroidism is the only endocrine deficiency disease for which the missing hormone, PTH, is not yet an approved therapy. Conventional therapy includes calcium and active vitamin D supplementation, often in large doses. Although serum calcium can be controlled with conventional therapy, it can be a challenge and, moreover, does not address other aspects of the disease, such as abnormal skeletal features and reduced quality of life. This review focuses on PTH replacement therapy in hypoparathyroidism, utilizing the full-length molecule PTH(1-84) as well as the fully active but truncated form PTH(1-34). PTH therapy addresses some aspects of the disease not ameliorated with conventional therapy.

  12. Progestogens in menopausal hormone therapy

    PubMed Central

    Woroń, Jarosław

    2015-01-01

    Progestogens share one common effect: the ability to convert proliferative endometrium to its secretory form. In contrast, their biological activity is varied, depending on the chemical structure, pharmacokinetics, receptor affinity and different potency of action. Progestogens are widely used in the treatment of menstrual cycle disturbances, various gynaecological conditions, contraception and menopausal hormone therapy. The administration of progestogen in menopausal hormone therapy is essential in women with an intact uterus to protect against endometrial hyperplasia and cancer. Progestogen selection should be based on the characteristics available for each progestogen type, relying on the assessment of relative potency of action in experimental models and animal models, and on the indirect knowledge brought by studies of the clinical use of different progestogen formulations. The choice of progestogen should involve the conscious use of knowledge of its benefits, with a focus on minimizing potential side effects. Unfortunately, there are no direct clinical studies comparing the metabolic effects of different progestogens. PMID:26327902

  13. Long-acting hormonal contraception.

    PubMed

    Benagiano, Giuseppe; Gabelnick, Henry; Brosens, Ivo

    2015-11-01

    Today, a new category of fertility-regulating agents has been created: long-acting, reversible hormonal contraceptives; they minimize compliance, while maximize effectiveness. They comprise subdermal implants and intrauterine devices. Other long-acting agents exist, such as Depo Provera and Noristerat. Use of Depo Provera and Noristerat carries great effectiveness, good clinical safety and usefulness in developing countries. They cause no significant increase in breast cancer risk, but they may carry an increased risk of HIV. Subcutaneous delivery systems have two common features: prolongation of effect is obtained by a drug reservoir and for most of their duration of action they provide a continuous, sustained release of the active hormone. Finally, the intrauterine system Mirena represents both a very effective contraceptive and a specific treatment for menorrhagia.

  14. Thyroid hormone regulation of metabolism.

    PubMed

    Mullur, Rashmi; Liu, Yan-Yun; Brent, Gregory A

    2014-04-01

    Thyroid hormone (TH) is required for normal development as well as regulating metabolism in the adult. The thyroid hormone receptor (TR) isoforms, α and β, are differentially expressed in tissues and have distinct roles in TH signaling. Local activation of thyroxine (T4), to the active form, triiodothyronine (T3), by 5'-deiodinase type 2 (D2) is a key mechanism of TH regulation of metabolism. D2 is expressed in the hypothalamus, white fat, brown adipose tissue (BAT), and skeletal muscle and is required for adaptive thermogenesis. The thyroid gland is regulated by thyrotropin releasing hormone (TRH) and thyroid stimulating hormone (TSH). In addition to TRH/TSH regulation by TH feedback, there is central modulation by nutritional signals, such as leptin, as well as peptides regulating appetite. The nutrient status of the cell provides feedback on TH signaling pathways through epigentic modification of histones. Integration of TH signaling with the adrenergic nervous system occurs peripherally, in liver, white fat, and BAT, but also centrally, in the hypothalamus. TR regulates cholesterol and carbohydrate metabolism through direct actions on gene expression as well as cross-talk with other nuclear receptors, including peroxisome proliferator-activated receptor (PPAR), liver X receptor (LXR), and bile acid signaling pathways. TH modulates hepatic insulin sensitivity, especially important for the suppression of hepatic gluconeogenesis. The role of TH in regulating metabolic pathways has led to several new therapeutic targets for metabolic disorders. Understanding the mechanisms and interactions of the various TH signaling pathways in metabolism will improve our likelihood of identifying effective and selective targets.

  15. Parathyroid Hormone Levels and Cognition

    NASA Technical Reports Server (NTRS)

    Burnett, J.; Smith, S.M.; Aung, K.; Dyer, C.

    2009-01-01

    Hyperparathyroidism is a well-recognized cause of impaired cognition due to hypercalcemia. However, recent studies have suggested that perhaps parathyroid hormone itself plays a role in cognition, especially executive dysfunction. The purpose of this study was to explore the relationship of parathyroid hormone levels in a study cohort of elders with impaied cognition. Methods: Sixty community-living adults, 65 years of age and older, reported to Adult Protective Services for self-neglect and 55 controls matched (on age, ethnicity, gender and socio-economic status) consented and participated in this study. The research team conducted in-home comprehensive geriatric assessments which included the Mini-mental state exam (MMSE), the 15-item geriatric depression scale (GDS) , the Wolf-Klein clock test and a comprehensive nutritional panel, which included parathyroid hormone and ionized calcium. Students t tests and linear regression analyses were performed to assess for bivariate associations. Results: Self-neglecters (M = 73.73, sd=48.4) had significantly higher PTH levels compared to controls (M =47.59, sd=28.7; t=3.59, df=98.94, p<.01). There was no significant group difference in ionized calcium levels. Overall, PTH was correlated with the MMSE (r=-.323, p=.001). Individual regression analyses revealed a statistically significant correlation between PTH and MMSE in the self-neglect group (r=-.298, p=.024) and this remained significant after controlling for ionized calcium levels in the regression. No significant associations were revealed in the control group or among any of the other cognitive measures. Conclusion: Parathyroid hormone may be associated with cognitive performance.

  16. Premenstrual changes. Impaired hormonal homeostasis.

    PubMed

    Halbreich, U; Alt, I H; Paul, L

    1988-03-01

    Premenstrual changes (PMCs) in mood and behavior are very prevalent. Nonetheless, their pathophysiology is still obscure and no proven treatment is yet available. Evaluation of the plethora of available data leads to the suggestion that PMCs may result from a temporary impairment of homeostasis among a multitude of systems. This impairment is triggered by a differential pace and magnitude of change-over-time in levels of several hormones and other substances during the luteal phase. PMID:3288473

  17. [Neurotropic action of adrenocorticotropic hormone].

    PubMed

    Louis, J C; Anglard, P; Vincendon, G

    1986-02-01

    The adrenocorticotropic hormone (ACTH) is produced within the cell body of hypothalamic neurons by proteolytic cleavage of its large precursor molecule, pro-opiomelanocortin. These neurons distribute ACTH-containing nerve endings throughout the central nervous system. ACTH is able to evoke motor and behavioural responses and to modify neuronal metabolism. Since ACTH has been shown to regulate glucose uptake and utilization, its implication in the adaptative response to stress situations, such as cerebral hypoxia, deserves further investigations. PMID:3008142

  18. Keeping circadian time with hormones.

    PubMed

    Challet, E

    2015-09-01

    Daily variations of metabolism, physiology and behaviour are controlled by a network of coupled circadian clocks, comprising a master clock in the suprachiasmatic nuclei of the hypothalamus and a multitude of secondary clocks in the brain and peripheral organs. Light cues synchronize the master clock that conveys temporal cues to other body clocks via neuronal and hormonal signals. Feeding at unusual times can reset the phase of most peripheral clocks. While the neuroendocrine aspect of circadian regulation has been underappreciated, this review aims at showing that the role of hormonal rhythms as internal time-givers is the rule rather than the exception. Adrenal glucocorticoids, pineal melatonin and adipocyte-derived leptin participate in internal synchronization (coupling) within the multi-oscillatory network. Furthermore, pancreatic insulin is involved in food synchronization of peripheral clocks, while stomach ghrelin provides temporal signals modulating behavioural anticipation of mealtime. Circadian desynchronization induced by shift work or chronic jet lag has harmful effects on metabolic regulation, thus favouring diabetes and obesity. Circadian deregulation of hormonal rhythms may participate in internal desynchronization and associated increase in metabolic risks. Conversely, adequate timing of endocrine therapies can promote phase-adjustment of the master clock (e.g. via melatonin agonists) and peripheral clocks (e.g. via glucocorticoid agonists).

  19. Hormonal regulation of female reproduction.

    PubMed

    Christensen, A; Bentley, G E; Cabrera, R; Ortega, H H; Perfito, N; Wu, T J; Micevych, P

    2012-07-01

    Reproduction is an event that requires the coordination of peripheral organs with the nervous system to ensure that the internal and external environments are optimal for successful procreation of the species. This is accomplished by the hypothalamic-pituitary-gonadal axis that coordinates reproductive behavior with ovulation. The primary signal from the central nervous system is gonadotropin-releasing hormone (GnRH), which modulates the activity of anterior pituitary gonadotropes regulating follicle stimulating hormone (FSH) and luteinizing hormone (LH) release. As ovarian follicles develop they release estradiol, which negatively regulates further release of GnRH and FSH. As estradiol concentrations peak they trigger the surge release of GnRH, which leads to LH release inducing ovulation. Release of GnRH within the central nervous system helps modulate reproductive behaviors providing a node at which control of reproduction is regulated. To address these issues, this review focuses on several critical questions. How is the HPG axis regulated in species with different reproductive strategies? What internal and external conditions modulate the synthesis and release of GnRH? How does GnRH modulate reproductive behavior within the hypothalamus? How does disease shift the activity of the HPG axis?

  20. Sex Hormones and Macronutrient Metabolism

    PubMed Central

    Comitato, Raffaella; Saba, Anna; Turrini, Aida; Arganini, Claudia; Virgili, Fabio

    2015-01-01

    The biological differences between males and females are determined by a different set of genes and by a different reactivity to environmental stimuli, including the diet, in general. These differences are further emphasized and driven by the exposure to a different hormone flux throughout the life. These differences have not been taken into appropriate consideration by the scientific community. Nutritional sciences are not immune from this “bias” and when nutritional needs are concerned, females are considered only when pregnant, lactating or when their hormonal profile is returning back to “normal,” i.e., to the male-like profile. The authors highlight some of the most evident differences in aspects of biology that are associated with nutrition. This review presents and describes available data addressing differences and similarities of the “reference man” vs. the “reference woman” in term of metabolic activity and nutritional needs. According to this assumption, available evidences of sex-associated differences of specific biochemical pathways involved in substrate metabolism are reported and discussed. The modulation by sexual hormones affecting glucose, amino acid and protein metabolism and the metabolization of nutritional fats and the distribution of fat depots, is considered targeting a tentative starting up background for a gender concerned nutritional science. PMID:24915409

  1. Growth hormone deficiency: an update.

    PubMed

    Audí, L; Fernández-Cancio, M; Camats, N; Carrascosa, A

    2013-03-01

    Growth hormone (GH) deficiency (GHD) in humans manifests differently according to the individual developmental stage (early after birth, during childhood, at puberty or in adulthood), the cause or mechanism (genetic, acquired or idiopathic), deficiency intensity and whether it is the only pituitary-affected hormone or is combined with that of other pituitary hormones or forms part of a complex syndrome. Growing knowledge of the genetic basis of GH deficiency continues to provide us with useful information to further characterise mutation types and mechanisms for previously described and new candidate genes. Despite these advances, a high proportion of GH deficiencies with no recognisable acquired basis continue to be labelled as idiopathic, although less frequently when they are congenital and/or familial. The clinical and biochemical diagnoses continue to be a conundrum despite efforts to harmonise biochemical assays for GH and IGF-1 analysis, probably because the diagnosis based on the so-called GH secretion stimulation tests will prove to be of limited usefulness for predicting therapy indications.

  2. Steroid hormones in cluster headaches.

    PubMed

    Stillman, Mark

    2006-04-01

    For decades, glucocorticoid therapy has been a well-recognized abortive treatment for cluster headaches. However, the role of steroid hormones, including both glucocorticoids and sex steroids, in the pathophysiology and therapy of cluster headaches has been a topic of much debate and speculation. Current research now points to the importance of cortisol and testosterone in the pathogenesis of cluster headaches, and they appear to be linked mechanistically to another hormone, melatonin. Melatonin, unlike cortisol or testosterone, is not a product of the hypothalamic pituitary axis but of the retinohypothalamic pineal axis, and is the major biomarker of circadian rhythms. The regulation of steroids and melatonin in the pathogenesis of cluster headaches in turn depends on the sympathetic nervous system. Accumulated evidence suggests sympathetic dysfunction--embodied in the Horner sign so commonly seen in the cluster headache--as a necessary ingredient in the inception of the cluster headache. Sympathetic dysfunction now is thought to be associated with the hypercortisolism, hypotestosteronism, and lower-than-normal melatonin levels in the active cluster patient. Future research may hold the key to a fuller explanation of the complex interaction of hormonal systems in the cluster headache.

  3. The growth hormone secretagogue receptor.

    PubMed

    Cruz, Conrad Russell Young; Smith, Roy G

    2008-01-01

    The neuroendocrine hormone ghrelin, a recently discovered acylated peptide with numerous activities in various organ systems, exerts most of its known effects on the body through a highly conserved G-protein-coupled receptor, the growth hormone secretagogue receptor (GHSR) type 1a. The GHSR's wide expression in different tissues reflects activity of its ligands in the hypothalamic-pituitary, cardiovascular, immune, gastrointestinal, and reproductive systems. Its extensive cellular distribution along with its important actions on the growth hormone (GH)/insulin-like growth factor-1 (IGF-1) axis and other neuroendocrine and metabolic systems suggest a pivotal role in governing the mechanisms of aging. A more comprehensive characterization of the receptor, and a more thorough identification of its various agonists and antagonists, will undoubtedly introduce important clinical applications in age-related states like anorexia, cardiovascular pathology, cancer, impaired energy balance, and immune dysfunction. Although present knowledge points to a single functional receptor and a single endogenous ligand, recent investigations suggest the existence of additional GHSR subtypes, as well as other endogenous agonists. It has been more than a decade since the landmark cloning of this ubiquitous, highly conserved receptor, and the considerable extent of its effects on normal physiology and disease states have filled the literature with incredible insights on how organisms regulate various functions through subtle signaling processes. But science has barely scratched the surface, and we can be assured that the mysteries surrounding the precise nature of ghrelin and its receptor(s) are only beginning to unravel. PMID:17983853

  4. Thyroid hormone receptors bind to defined regions of the growth hormone and placental lactogen genes.

    PubMed Central

    Barlow, J W; Voz, M L; Eliard, P H; Mathy-Harter, M; De Nayer, P; Economidis, I V; Belayew, A; Martial, J A; Rousseau, G G

    1986-01-01

    The intracellular receptor for thyroid hormone is a protein found in chromatin. Since thyroid hormone stimulates transcription of the growth hormone gene through an unknown mechanism, the hypothesis that the thyroid hormone-receptor complex interacts with defined regions of this gene has been investigated in a cell-free system. Nuclear extracts from human lymphoblastoid IM-9 cells containing thyroid hormone receptors were incubated with L-3,5,3'-tri[125I]iodothyronine and calf thymus DNA-cellulose. Restriction fragments of the human growth hormone gene were added to determine their ability to inhibit labeled receptor binding to DNA-cellulose. These fragments encompassed nucleotide sequences from about three kilobase pairs upstream to about four kilobase pairs downstream from the transcription initiation site. The thyroid hormone-receptor complex bound preferentially to the 5'-flanking sequences of the growth hormone gene in a region between nucleotide coordinates -290 and -129. The receptor also bound to an analogous promoter region in the human placental lactogen gene, which has 92% nucleotide sequence homology with the growth hormone gene. These binding regions appear to be distinct from those that are recognized by the receptor for glucocorticoids, which stimulate growth hormone gene expression synergistically with thyroid hormone. The presence of thyroid hormone was required for binding of its receptor to the growth hormone gene promoter, suggesting that thyroid hormone renders the receptor capable of recognizing specific gene regions. PMID:3466175

  5. Interactions of growth hormone secretagogues and growth hormone-releasing hormone/somatostatin.

    PubMed

    Tannenbaum, G S; Bowers, C Y

    2001-02-01

    The class of novel synthetic compounds termed growth hormone secretagogues (GHSs) act in the hypothalamus through, as yet, unknown pathways. We performed physiologic and histochemical studies to further understand how the GHS system interacts with the well-established somatostatin (SRIF)/growth hormone-releasing hormone (GHRH) neuroendocrine system for regulating pulsatile GH secretion. Comparison of the GH-releasing activities of the hexapeptide growth hormone-releasing peptide-6 (GHRP-6) and GHRH administered intravenously to conscious adult male rats showed that the pattern of GH responsiveness to GHRP-6 was markedly time-dependent, similar to that observed with GHRH. Immunoneutralization of endogenous SRIF reversed the blunted GH response to GHRP-6 at trough times, suggesting that GHRP-6 neither disrupts nor inhibits the cyclical release of endogenous hypothalamic SRIF. By striking contrast, passive immunization with anti-GHRH serum virtually obliterated the GH responses to GHRP-6, irrespective of the time of administration. These findings suggest that the GHSs do not act by altering SRIF release but, rather, stimulate GH release via GHRH-dependent pathways. Our dual chromogenic and autoradiographic in situ hybridization experiments revealed that a subpopulation of GHRH mRNA-containing neurons in the arcuate (Arc) nucleus and ventromedial nucleus (VMN) of the hypothalamus expressed the GHS receptor (GHS-R) gene. These results provide strong anatomic evidence that GHSs may directly stimulate GHRH release into hypophyseal portal blood, and thereby influence GH secretion, through interaction with the GHS-R on GHRH- containing neurons. Altogether, these findings support the notion that an additional neuroendocrine pathway may exist to regulate pulsatile GH secretion, possibly through the influence of the newly discovered GHS natural peptide, ghrelin. PMID:11322498

  6. Hormone symphony during root growth and development.

    PubMed

    Garay-Arroyo, Adriana; De La Paz Sánchez, María; García-Ponce, Berenice; Azpeitia, Eugenio; Alvarez-Buylla, Elena R

    2012-12-01

    Hormones regulate plant growth and development in response to external environmental stimuli via complex signal transduction pathways, which in turn form complex networks of interaction. Several classes of hormones have been reported, and their activity depends on their biosynthesis, transport, conjugation, accumulation in the vacuole, and degradation. However, the activity of a given hormone is also dependent on its interaction with other hormones. Indeed, there is a complex crosstalk between hormones that regulates their biosynthesis, transport, and/or signaling functionality, although some hormones have overlapping or opposite functions. The plant root is a particularly useful system in which to study the complex role of plant hormones in the plastic control of plant development. Physiological, cellular, and molecular genetic approaches have been used to study the role of plant hormones in root meristem homeostasis. In this review, we discuss recent findings on the synthesis, signaling, transport of hormones and role during root development and examine the role of hormone crosstalk in maintaining homeostasis in the apical root meristem.

  7. Gastrointestinal hormone research - with a Scandinavian annotation.

    PubMed

    Rehfeld, Jens F

    2015-06-01

    Gastrointestinal hormones are peptides released from neuroendocrine cells in the digestive tract. More than 30 hormone genes are currently known to be expressed in the gut, which makes it the largest hormone-producing organ in the body. Modern biology makes it feasible to conceive the hormones under five headings: The structural homology groups a majority of the hormones into nine families, each of which is assumed to originate from one ancestral gene. The individual hormone gene often has multiple phenotypes due to alternative splicing, tandem organization or differentiated posttranslational maturation of the prohormone. By a combination of these mechanisms, more than 100 different hormonally active peptides are released from the gut. Gut hormone genes are also widely expressed outside the gut, some only in extraintestinal endocrine cells and cerebral or peripheral neurons but others also in other cell types. The extraintestinal cells may release different bioactive fragments of the same prohormone due to cell-specific processing pathways. Moreover, endocrine cells, neurons, cancer cells and, for instance, spermatozoa secrete gut peptides in different ways, so the same peptide may act as a blood-borne hormone, a neurotransmitter, a local growth factor or a fertility factor. The targets of gastrointestinal hormones are specific G-protein-coupled receptors that are expressed in the cell membranes also outside the digestive tract. Thus, gut hormones not only regulate digestive functions, but also constitute regulatory systems operating in the whole organism. This overview of gut hormone biology is supplemented with an annotation on some Scandinavian contributions to gastrointestinal hormone research.

  8. Drosophila TRPA1 isoforms detect UV light via photochemical production of H2O2.

    PubMed

    Guntur, Ananya R; Gu, Pengyu; Takle, Kendra; Chen, Jingyi; Xiang, Yang; Yang, Chung-Hui

    2015-10-20

    The transient receptor potential A1 (TRPA1) channel is an evolutionarily conserved detector of temperature and irritant chemicals. Here, we show that two specific isoforms of TRPA1 in Drosophila are H2O2 sensitive and that they can detect strong UV light via sensing light-induced production of H2O2. We found that ectopic expression of these H2O2-sensitive Drosophila TRPA1 (dTRPA1) isoforms conferred UV sensitivity to light-insensitive HEK293 cells and Drosophila neurons, whereas expressing the H2O2-insensitive isoform did not. Curiously, when expressed in one specific group of motor neurons in adult flies, the H2O2-sensitive dTRPA1 isoforms were as competent as the blue light-gated channelrhodopsin-2 in triggering motor output in response to light. We found that the corpus cardiacum (CC) cells, a group of neuroendocrine cells that produce the adipokinetic hormone (AKH) in the larval ring gland endogenously express these H2O2-sensitive dTRPA1 isoforms and that they are UV sensitive. Sensitivity of CC cells required dTRPA1 and H2O2 production but not conventional phototransduction molecules. Our results suggest that specific isoforms of dTRPA1 can sense UV light via photochemical production of H2O2. We speculate that UV sensitivity conferred by these isoforms in CC cells may allow young larvae to activate stress response--a function of CC cells--when they encounter strong UV, an aversive stimulus for young larvae.

  9. Drosophila TRPA1 isoforms detect UV light via photochemical production of H2O2

    PubMed Central

    Guntur, Ananya R.; Gu, Pengyu; Takle, Kendra; Chen, Jingyi; Xiang, Yang; Yang, Chung-Hui

    2015-01-01

    The transient receptor potential A1 (TRPA1) channel is an evolutionarily conserved detector of temperature and irritant chemicals. Here, we show that two specific isoforms of TRPA1 in Drosophila are H2O2 sensitive and that they can detect strong UV light via sensing light-induced production of H2O2. We found that ectopic expression of these H2O2-sensitive Drosophila TRPA1 (dTRPA1) isoforms conferred UV sensitivity to light-insensitive HEK293 cells and Drosophila neurons, whereas expressing the H2O2-insensitive isoform did not. Curiously, when expressed in one specific group of motor neurons in adult flies, the H2O2-sensitive dTRPA1 isoforms were as competent as the blue light-gated channelrhodopsin-2 in triggering motor output in response to light. We found that the corpus cardiacum (CC) cells, a group of neuroendocrine cells that produce the adipokinetic hormone (AKH) in the larval ring gland endogenously express these H2O2-sensitive dTRPA1 isoforms and that they are UV sensitive. Sensitivity of CC cells required dTRPA1 and H2O2 production but not conventional phototransduction molecules. Our results suggest that specific isoforms of dTRPA1 can sense UV light via photochemical production of H2O2. We speculate that UV sensitivity conferred by these isoforms in CC cells may allow young larvae to activate stress response—a function of CC cells—when they encounter strong UV, an aversive stimulus for young larvae. PMID:26443856

  10. Sex steroids and growth hormone interactions.

    PubMed

    Fernández-Pérez, Leandro; de Mirecki-Garrido, Mercedes; Guerra, Borja; Díaz, Mario; Díaz-Chico, Juan Carlos

    2016-04-01

    GH and sex hormones are critical regulators of body growth and composition, somatic development, intermediate metabolism, and sexual dimorphism. Deficiencies in GH- or sex hormone-dependent signaling and the influence of sex hormones on GH biology may have a dramatic impact on liver physiology during somatic development and in adulthood. Effects of sex hormones on the liver may be direct, through hepatic receptors, or indirect by modulating endocrine, metabolic, and gender-differentiated functions of GH. Sex hormones can modulate GH actions by acting centrally, regulating pituitary GH secretion, and peripherally, by modulating GH signaling pathways. The endocrine and/or metabolic consequences of long-term exposure to sex hormone-related compounds and their influence on the GH-liver axis are largely unknown. A better understanding of these interactions in physiological and pathological states will contribute to preserve health and to improve clinical management of patients with growth, developmental, and metabolic disorders.

  11. Thyroid hormone resistance and its management

    PubMed Central

    Lado-Abeal, Joaquin

    2016-01-01

    The syndrome of impaired sensitivity to thyroid hormone, also known as syndrome of thyroid hormone resistance, is an inherited condition that occurs in 1 of 40,000 live births characterized by a reduced responsiveness of target tissues to thyroid hormone due to mutations on the thyroid hormone receptor. Patients can present with symptoms of hyperthyroidism or hypothyroidism. They usually have elevated thyroid hormones and a normal or elevated thyroid-stimulating hormone level. Due to their nonspecific symptomatic presentation, these patients can be misdiagnosed if the primary care physician is not familiar with the condition. This can result in frustration for the patient and sometimes unnecessary invasive treatment such as radioactive iodine ablation, as in the case presented herein. PMID:27034574

  12. Ectopic acromegaly due to growth hormone releasing hormone.

    PubMed

    Ghazi, Ali A; Amirbaigloo, Alireza; Dezfooli, Azizollah Abbasi; Saadat, Navid; Ghazi, Siavash; Pourafkari, Marina; Tirgari, Farrokh; Dhall, Dheepti; Bannykh, Serguei; Melmed, Shlomo; Cooper, Odelia

    2013-04-01

    Acromegaly secondary to extra-pituitary tumors secreting growth hormone releasing hormone (GHRH) is rarely encountered. We review the literature on ectopic acromegaly and present the index report of ectopic acromegaly secondary to GHRH secretion from a mediastinal paraganglioma. Clinical and pathological manifestations and therapeutic management of 99 patients with ectopic acromegaly are reviewed. Acromegaly secondary to ectopic GHRH secretion is usually caused by a neuroendocrine tumor in the lung and pancreas. We report an additional cause of ectopic acromegaly from a mediastinal paraganglioma. Diagnostic criteria of ectopic GHRH syndrome include biochemical and pathologic tumoral confirmation of GHRH secretion and expression. Management of ectopic acromegaly consists of surgical resection of the primary tumor and biochemical normalization, with possible adjuvant use of somatostatin analogs. The review demonstrates that there are several tumor types, including paragangliomas which may secrete GHRH, leading to acromegaly. Clinical and laboratory manifestations of the syndrome and challenges in diagnosis and management of these rarely encountered patients require early diagnosis and appropriate treatment to prevent long-term morbidity and mortality with ectopic acromegaly. PMID:22983831

  13. [Hormone profiles and hormone therapy in early pregnancy (author's transl)].

    PubMed

    Friedrich, F; Kemeter, P; Salzer, H; Kratochwil, A; Knapp-Groll, E

    1978-08-11

    Hormone profiles in early pregnancy were established in 67 women and correlated to simultaneously performed ultrasonic examinations. Normal values for human chorionic gonadotropin (HCG), human chorionic somatotropin (HCS), oestradiol (E2) and progesterone (P) were established from the data obtained in 30 early pregnancies which culminated in the birth of a living child. Lowered HCG values were found in 17 out of 23 pregnancies which ended in miscarriage. In these cases ultrasonic examination failed to detect any heart action. Lowered HCS values after the 9th week of pregnancy are also certain proof of missed abortion. P and E2 values are shown to be a parameter reflecting activity of the corpus luteum graviditatis. In clomiphene- and gonadotropin-induced pregnancies higher values were found than in pregnancies managed by substitution treatment with twice weekly 10 mg oestradiolvalerianate + 500mg 17alpha-hydroxyprogesteronecapronate. Lowered P and E2 values with HCG values in the normal range indicate imminent insufficiency of the corpus luteum graviditatis. Pros and cons of hormonal therapy in early pregnancy are discussed. PMID:676313

  14. Aluminum, parathyroid hormone, and osteomalacia

    SciTech Connect

    Burnatowska-Hledin, M.A.; Kaiser, L.; Mayor, G.H.

    1983-01-01

    Aluminum exposure in man is unavoidable. The occurrence of dialysis dementia, vitamin D-resistant osteomalacia, and hypochromic microcytic anemia in dialysis patients underscores the potential for aluminum toxicity. Although exposure via dialysate and hyperalimentation leads to significant tissue aluminum accumulation, the ubiquitous occurrence of aluminum and the severe pathology associated with large aluminum burdens suggest that smaller exposures via the gastrointestinal tract and lungs could represent an important, though largely unrecognized, public health problem. It is clear that some aluminum absorption occurs with the ingestion of small amounts of aluminum in the diet and medicines, and even greater aluminum absorption is seen in individuals consuming large amounts of aluminum present in antacids. Aluminum absorption is enhanced in the presence of elevated circulating parathyroid hormone. In addition, elevated PTH leads to the preferential deposition of aluminum in brain and bone. Consequently, PTH is likely to be involved in the pathogenesis of toxicities in those organs. PTH excess also seems to lead to the deposition of aluminum in the parathyroid gland. The in vitro demonstration that aluminum inhibits parathyroid hormone release is consistent with the findings of a euparathyroid state in dialysis patients with aluminum related vitamin D-resistant osteomalacia. Nevertheless, it seems likely that hyperparathyroidism is at least initially involved in the pathogenesis of aluminum neurotoxicity and osteomalacia; the increases in tissue aluminum stores are followed by suppression of parathyroid hormone release, which is required for the evolution of osteomalacia. Impaired renal function is not a prerequisite for increased tissue aluminum burdens, nor for aluminum-related organ toxicity. Consequently, it is likely that these diseases will be observed in populations other than those with chronic renal disease.

  15. Pharmacologic development of male hormonal contraceptive agents.

    PubMed

    Roth, M Y; Amory, J K

    2011-01-01

    The world population continues to increase dramatically despite the existence of contraceptive technology. The use of male hormonal contraception may help in preventing un intended pregnancies and managing future population growth. Male hormonal contraception relies on the administration of exogenous hormones to suppress spermatogenesis. Clinical trials have tested several regimens using testosterone, alone or in combination with a progestin. These regimens were shown to be >90% effective in preventing conception and were not associated with serious adverse events.

  16. Hormonal Treatment of Acne in Women

    PubMed Central

    Ebede, Tobechi L.; Arch, Emily L.

    2009-01-01

    Acne vulgaris is a common and chronic disorder of the pilosebaceous unit. Standard treatment protocols include topical retinoids, topical and oral antimicrobials, and isotretinoin. Hormonal therapies can be added to the regimen in some patients. This article will review the hormonal pathogenesis of acne, discuss the basics of an endocrine evaluation, and provide an overview of the current hormonal treatment options in women. PMID:20725580

  17. Simultaneous radioimmunoassay for luteinizing hormone and prolactin

    SciTech Connect

    Steele, M.K.; Deschepper, C.F.

    1985-05-01

    A combined radioimmunoassay (RIA) for the measurement of the anterior pituitary proteins luteinizing hormone (LH) and prolactin (PRL) is described and compared with individual RIAs for these hormones. The standard curves and the sample values for LH and PRL were identical when determined in a combined or in an individual RIA. This technique may prove useful to a number of laboratories where it is desirable to determine levels of more than one hormone in limited sample volumes.

  18. [Laboratory diagnosis of growth hormone].

    PubMed

    Macchia, V; Mariano, A

    1993-09-01

    The role of Clinical Pathology Laboratory in normal and altered growth hormone secretion is discussed. In particular, it is reported that the normal GH secretion can be studied by serum and urine GH determinations whereas the diagnosis of GH deficiency rests upon the demonstration of an inadequate rise serum GH after provocative stimuli and serum measurement of somatomedins (IGF-I) by radioimmunoassay method. As it concerns increase GH secretion the diagnosis is clinically made (acromegaly and gigantism) and the laboratory has only the role to confirm it by the assessment of basal and stimulated GH secretion. PMID:7910655

  19. Growth hormone and its disorders.

    PubMed

    Ayuk, J; Sheppard, M C

    2006-01-01

    Growth hormone (GH) is synthesised and secreted by the somatotroph cells of the anterior lobe of the pituitary gland. Its actions involve multiple organs and systems, affecting postnatal longitudinal growth as well as protein, lipid, and carbohydrate metabolism. GH hypersecretion results in gigantism or acromegaly, a condition associated with significant morbidity and mortality, while GH deficiency results in growth retardation in children and the GH deficiency syndrome in adults. This article, aimed at non-paediatric physicians, examines the clinical features, diagnosis, and current concepts in the management of these conditions. PMID:16397076

  20. Growth Hormone and Craniofacial Tissues. An update

    PubMed Central

    Litsas, George

    2015-01-01

    Growth hormone is an important regulator of bone homeostasis. In childhood, it determines the longitudinal bone growth, skeletal maturation, and acquisition of bone mass. In adulthood, it is necessary to maintain bone mass throughout life. Although an association between craniofacial and somatic development has been clearly established, craniofacial growth involves complex interactions of genes, hormones and environment. Moreover, as an anabolic hormone seems to have an important role in the regulation of bone remodeling, muscle enhancement and tooth development. In this paper the influence of growth hormone on oral tissues is reviewed. PMID:25674165

  1. Effects of hormones on platelet aggregation.

    PubMed

    Farré, Antonio López; Modrego, Javier; Zamorano-León, José J

    2014-04-01

    Platelets and their activation/inhibition mechanisms play a central role in haemostasis. It is well known agonists and antagonists of platelet activation; however, during the last years novel evidences of hormone effects on platelet activation have been reported. Platelet functionality may be modulated by the interaction between different hormones and their platelet receptors, contributing to sex differences in platelet function and even in platelet-mediated vascular damage. It has suggested aspects that apparently are well established should be reviewed. Hormones effects on platelet activity are included among them. This article tries to review knowledge about the involvement of hormones in platelet biology and activity.

  2. Hormones and the blood-brain barrier.

    PubMed

    Hampl, Richard; Bičíková, Marie; Sosvorová, Lucie

    2015-03-01

    Hormones exert many actions in the brain, and brain cells are also hormonally active. To reach their targets in brain structures, hormones must overcome the blood-brain barrier (BBB). The BBB is a unique device selecting desired/undesired molecules to reach or leave the brain, and it is composed of endothelial cells forming the brain vasculature. These cells differ from other endothelial cells in their almost impermeable tight junctions and in possessing several membrane structures such as receptors, transporters, and metabolically active molecules, ensuring their selection function. The main ways how compounds pass through the BBB are briefly outlined in this review. The main part concerns the transport of major classes of hormones: steroids, including neurosteroids, thyroid hormones, insulin, and other peptide hormones regulating energy homeostasis, growth hormone, and also various cytokines. Peptide transporters mediating the saturable transport of individual classes of hormones are reviewed. The last paragraph provides examples of how hormones affect the permeability and function of the BBB either at the level of tight junctions or by various transporters.

  3. Determinants of Growth Hormone Resistance in Malnutrition

    PubMed Central

    Fazeli, Pouneh K.; Klibanski, Anne

    2014-01-01

    States of under-nutrition are characterized by growth hormone resistance. Decreased total energy intake, as well as isolated protein-calorie malnutrition and isolated nutrient deficiencies result in elevated growth hormone levels and low levels of IGF-I. We review various states of malnutrition and a disease state characterized by chronic under-nutrition -- anorexia nervosa -- and discuss possible mechanisms contributing to the state of growth hormone resistance, including FGF-21 and SIRT1. We conclude by examining the hypothesis that growth hormone resistance is an adaptive response to states of under-nutrition, in order to maintain euglycemia and preserve energy. PMID:24363451

  4. Postmenopausal hormone therapy and cognition.

    PubMed

    McCarrey, Anna C; Resnick, Susan M

    2015-08-01

    This article is part of a Special Issue "Estradiol and cognition". Prior to the publication of findings from the Women's Health Initiative (WHI) in 2002, estrogen-containing hormone therapy (HT) was used to prevent age-related disease, especially cardiovascular disease, and to treat menopausal symptoms such as hot flushes and sleep disruptions. Some observational studies of HT in midlife and aging women suggested that HT might also benefit cognitive function, but randomized clinical trials have produced mixed findings in terms of health and cognitive outcomes. This review focuses on hormone effects on cognition and risk for dementia in naturally menopausal women as well as surgically induced menopause, and highlights findings from the large-scale WHI Memory Study (WHIMS) which, contrary to expectation, showed increased dementia risk and poorer cognitive outcomes in older postmenopausal women randomized to HT versus placebo. We consider the 'critical window hypothesis', which suggests that a window of opportunity may exist shortly after menopause during which estrogen treatments are most effective. In addition, we highlight emerging evidence that potential adverse effects of HT on cognition are most pronounced in women who have other health risks, such as lower global cognition or diabetes. Lastly, we point towards implications for future research and clinical treatments.

  5. Alligators, contaminants and steroid hormones.

    PubMed

    Guillette, Louis J; Edwards, Thea M; Moore, Brandon C

    2007-01-01

    Steroids are essential for successful reproduction in all vertebrate species. Over the last several decades, extensive research has indicated that exposure to various environmental pollutants can disrupt steroidogenesis and steroid signaling. Although steroidogenesis is regulated by the hypothalamic-pituitary axis, it is also modified by various paracrine and autocrine factors. Furthermore, the classical two-cell model of steroidogenesis in the developing ovarian follicle, involving the granulosa and theca cells in mammals, may not be universal. Instead, birds and probably reptiles use the two thecal compartments (theca interna and theca externa) as sites of steroid production. We have documented that embryonic or juvenile exposure to a complex mixture of contaminants from agricultural and storm water runoff leads to altered steroid hormone profiles in American alligators. Our observations suggest that alterations in plasma steroid hormone concentrations are due in part to altered gene expression, modified hepatic biotransformation and altered gonadal steroidogenesis. Future studies must examine the interplay between endocrine and paracrine regulation in the development and expression of gonadal steroidogenesis in individuals exposed to endocrine disrupting contaminants at various life stages if we are to fully understand potential detrimental outcomes.

  6. Postmenopausal hormone therapy and cognition

    PubMed Central

    McCarrey, Anna C.; Resnick, Susan M.

    2015-01-01

    Prior to the publication of findings from the Women’s Health Initiative (WHI) in 2002, estrogen-containing hormone therapy (HT) was used to prevent age-related disease, especially cardiovascular disease, and to treat menopausal symptoms such as hot flushes and sleep disruptions. Some observational studies of HT in midlife and aging women suggested that HT might also benefit cognitive function, but randomized clinical trials have produced mixed findings in terms of health and cognitive outcomes. This review focuses on hormone effects on cognition and risk for dementia in naturally menopausal women as well as surgically induced menopause, and highlights findings from the large-scale WHI Memory Study (WHIMS) which, contrary to expectation, showed increased dementia risk and poorer cognitive outcomes in older postmenopausal women randomized to HT versus placebo. We consider the ‘critical window hypothesis’, which suggests that a window of opportunity may exist shortly after menopause during which estrogen treatments are most effective. In addition, we highlight emerging evidence that potential adverse effects of HT on cognition are most pronounced in women who have other health risks, such as cerebrovascular disease or diabetes. Lastly, we point towards implications for future research and clinical treatments. PMID:25935728

  7. Sex hormones and brain aging.

    PubMed

    Veiga, Sergio; Melcangi, Roberto C; Doncarlos, Lydia L; Garcia-Segura, Luis M; Azcoitia, Iñigo

    2004-01-01

    Sex steroids exert pleiotropic effects in the nervous system, preserving neural function and promoting neuronal survival. Therefore, the age-related decrease in sex steroids may have a negative impact on neural function. Progesterone, testosterone and estradiol prevent neuronal loss in the central nervous system in different experimental animal models of neurodegeneration. Furthermore, progesterone and its reduced derivatives dihydroprogesterone and tetrahydroprogesterone reduce aging-associated morphological abnormalities of myelin and aging-associated myelin fiber loss in rat peripheral nerves. However, the results from hormone replacement studies in humans are thus far inconclusive. A possible alternative to hormonal replacement therapy is to increase local steroidogenesis by neural tissues, which express enzymes for steroid synthesis and metabolism. Proteins involved in the intramitochondrial trafficking of cholesterol, the first step in steroidogenesis, such as the peripheral-type benzodiazepine receptor and the steroidogenic acute regulatory protein, are up-regulated in the nervous system after injury. Furthermore, steroidogenic acute regulatory protein expression is increased in the brain of 24-month-old rats compared with young adult rats. This suggests that brain steroidogenesis may be modified in adaptation to neurodegenerative conditions and to the brain aging process. Furthermore, recent studies have shown that local formation of estradiol in the brain, by the enzyme aromatase, is neuroprotective. Therefore, steroidogenic acute regulatory protein, peripheral-type benzodiazepine receptor and aromatase are attractive pharmacological targets to promote neuroprotection in the aged brain. PMID:15582278

  8. Hormonal mechanisms of cooperative behaviour

    PubMed Central

    Soares, Marta C.; Bshary, Redouan; Fusani, Leonida; Goymann, Wolfgang; Hau, Michaela; Hirschenhauser, Katharina; Oliveira, Rui F.

    2010-01-01

    Research on the diversity, evolution and stability of cooperative behaviour has generated a considerable body of work. As concepts simplify the real world, theoretical solutions are typically also simple. Real behaviour, in contrast, is often much more diverse. Such diversity, which is increasingly acknowledged to help in stabilizing cooperative outcomes, warrants detailed research about the proximate mechanisms underlying decision-making. Our aim here is to focus on the potential role of neuroendocrine mechanisms on the regulation of the expression of cooperative behaviour in vertebrates. We first provide a brief introduction into the neuroendocrine basis of social behaviour. We then evaluate how hormones may influence known cognitive modules that are involved in decision-making processes that may lead to cooperative behaviour. Based on this evaluation, we will discuss specific examples of how hormones may contribute to the variability of cooperative behaviour at three different levels: (i) within an individual; (ii) between individuals and (iii) between species. We hope that these ideas spur increased research on the behavioural endocrinology of cooperation. PMID:20679116

  9. Hormones as doping in sports.

    PubMed

    Duntas, Leonidas H; Popovic, Vera

    2013-04-01

    Though we may still sing today, as did Pindar in his eighth Olympian Victory Ode, "… of no contest greater than Olympia, Mother of Games, gold-wreathed Olympia…", we must sadly admit that today, besides blatant over-commercialization, there is no more ominous threat to the Olympic games than doping. Drug-use methods are steadily becoming more sophisticated and ever harder to detect, increasingly demanding the use of complex analytical procedures of biotechnology and molecular medicine. Special emphasis is thus given to anabolic androgenic steroids, recombinant growth hormone and erythropoietin as well as to gene doping, the newly developed mode of hormones abuse which, for its detection, necessitates high-tech methodology but also multidisciplinary individual measures incorporating educational and psychological methods. In this Olympic year, the present review offers an update on the current technologically advanced endocrine methods of doping while outlining the latest procedures applied-including both the successes and pitfalls of proteomics and metabolomics-to detect doping while contributing to combating this scourge.

  10. Growth Hormone Response after Administration of L-dopa, Clonidine, and Growth Hormone Releasing Hormone in Children with Down Syndrome.

    ERIC Educational Resources Information Center

    Pueschel, Seigfried M.

    1993-01-01

    This study of eight growth-retarded children with Down's syndrome (aged 1 to 6.5 years) found that administration of growth hormone was more effective than either L-dopa or clonidine. Results suggest that children with Down's syndrome have both anatomical and biochemical hypothalamic derangements resulting in decreased growth hormone secretion and…

  11. Ubiquitin, Hormones and Biotic Stress in Plants

    PubMed Central

    Dreher, Kate; Callis, Judy

    2007-01-01

    Background The covalent attachment of ubiquitin to a substrate protein changes its fate. Notably, proteins typically tagged with a lysine48-linked polyubiquitin chain become substrates for degradation by the 26S proteasome. In recent years many experiments have been performed to characterize the proteins involved in the ubiquitylation process and to identify their substrates, in order to understand better the mechanisms that link specific protein degradation events to regulation of plant growth and development. Scope This review focuses on the role that ubiquitin plays in hormone synthesis, hormonal signalling cascades and plant defence mechanisms. Several examples are given of how targeted degradation of proteins affects downstream transcriptional regulation of hormone-responsive genes in the auxin, gibberellin, abscisic acid, ethylene and jasmonate signalling pathways. Additional experiments suggest that ubiquitin-mediated proteolysis may also act upstream of the hormonal signalling cascades by regulating hormone biosynthesis, transport and perception. Moreover, several experiments demonstrate that hormonal cross-talk can occur at the level of proteolysis. The more recently established role of the ubiquitin/proteasome system (UPS) in defence against biotic threats is also reviewed. Conclusions The UPS has been implicated in the regulation of almost every developmental process in plants, from embryogenesis to floral organ production probably through its central role in many hormone pathways. More recent evidence provides molecular mechanisms for hormonal cross-talk and links the UPS system to biotic defence responses. PMID:17220175

  12. Insect Control (II): Hormones and Viruses

    ERIC Educational Resources Information Center

    Marx, Jean L.

    1973-01-01

    Discusses research in the use of hormones and viruses to control insect populations. Although entomologists do not think that pheromones, hormones, and viruses will completely replace more conventional chemical insecticides, they will become increasingly important and will reduce our dependence on traditional insecticides. (JR)

  13. The barrier within: endothelial transport of hormones.

    PubMed

    Kolka, Cathryn M; Bergman, Richard N

    2012-08-01

    Hormones are involved in a plethora of processes including development and growth, metabolism, mood, and immune responses. These essential functions are dependent on the ability of the hormone to access its target tissue. In the case of endocrine hormones that are transported through the blood, this often means that the endothelium must be crossed. Many studies have shown that the concentrations of hormones and nutrients in blood can be very different from those surrounding the cells on the tissue side of the blood vessel endothelium, suggesting that transport across this barrier can be rate limiting for hormone action. This transport can be regulated by altering the surface area of the blood vessel available for diffusion through to the underlying tissue or by the permeability of the endothelium. Many hormones are known to directly or indirectly affect the endothelial barrier, thus affecting their own distribution to their target tissues. Dysfunction of the endothelial barrier is found in many diseases, particularly those associated with the metabolic syndrome. The interrelatedness of hormones may help to explain why the cluster of diseases in the metabolic syndrome occur together so frequently and suggests that treating the endothelium may ameliorate defects in more than one disease. Here, we review the structure and function of the endothelium, its contribution to the function of hormones, and its involvement in disease.

  14. Menstrual cycle hormones, food intake, and cravings

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Objective: Food craving and intake are affected by steroid hormones during the menstrual cycle, especially in the luteal phase, when craving for certain foods has been reported to increase. However, satiety hormones such as leptin have also been shown to affect taste sensitivity, and therefore food ...

  15. Hormonal and Local Regulation of Bone Formation.

    ERIC Educational Resources Information Center

    Canalis, Ernesto

    1985-01-01

    Reviews effects of hormones, systemic factors, and local regulators on bone formation. Identifies and explains the impact on bone growth of several hormones as well as the components of systemic and local systems. Concentrates on bone collagen and DNA synthesis. (Physicians may earn continuing education credit by completing an appended test). (ML)

  16. Collective hormonal profiles predict group performance.

    PubMed

    Akinola, Modupe; Page-Gould, Elizabeth; Mehta, Pranjal H; Lu, Jackson G

    2016-08-30

    Prior research has shown that an individual's hormonal profile can influence the individual's social standing within a group. We introduce a different construct-a collective hormonal profile-which describes a group's hormonal make-up. We test whether a group's collective hormonal profile is related to its performance. Analysis of 370 individuals randomly assigned to work in 74 groups of three to six individuals revealed that group-level concentrations of testosterone and cortisol interact to predict a group's standing across groups. Groups with a collective hormonal profile characterized by high testosterone and low cortisol exhibited the highest performance. These collective hormonal level results remained reliable when controlling for personality traits and group-level variability in hormones. These findings support the hypothesis that groups with a biological propensity toward status pursuit (high testosterone) coupled with reduced stress-axis activity (low cortisol) engage in profit-maximizing decision-making. The current work extends the dual-hormone hypothesis to the collective level and provides a neurobiological perspective on the factors that determine who rises to the top across, not just within, social hierarchies. PMID:27528679

  17. Recombinant Bovine Growth Hormone Criticism Grows.

    ERIC Educational Resources Information Center

    Gaard, Greta

    1995-01-01

    Discusses concerns related to the use of recombinant bovine growth hormone in the United States and other countries. Analyses the issue from the perspectives of animal rights, human health, world hunger, concerns of small and organic farmers, costs to the taxpayer, and environmental questions. A sidebar discusses Canadian review of the hormone.…

  18. Hormones and pheromones in regulation of insect behavior

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Both pheromones and hormones are well recognized regulators of insect biology. However, the interactions between hormones and pheromones in coordinating insect biology are less well understood. We have studied the interactions between juvenile hormone, its precursor methyl farnesoate, and pheromon...

  19. Parathyroid Hormone, Calcitonin, and Vitamin D

    NASA Technical Reports Server (NTRS)

    Potts, J. T.

    1972-01-01

    Analyses of secretion of parathyroid hormone during tests of stimulation and suppression of hormone-secretory activity using infusions of EDTA and calcium, respectively, have established that, in contrast to previous views, secretion of the hormone is not autonomous in many patients that have adenomatous hyperparathyroidism, but is responsive to changes in blood-calcium concentration. These findings have led to a new understanding of the pathophysiology of hormone production in hyperparathy-roidism. A related application of the diagnostic use of the radioimmunoassay is the preoperative localization of parathyroid tumors and the distinction between adenomas and chief-cell hyperplasia. Work involving catheterization and radioimmunoassay of blood samples obtained from the subclavin and innominate veins and the venae cavae, led to localization in a high percentage of patients. However, this procedure has been adopted recently to detect hormone concentration in the small veins directly draining the parathyroid glands.

  20. [Plant hormones, plant growth regulators].

    PubMed

    Végvári, György; Vidéki, Edina

    2014-06-29

    Plants seem to be rather defenceless, they are unable to do motion, have no nervous system or immune system unlike animals. Besides this, plants do have hormones, though these substances are produced not in glands. In view of their complexity they lagged behind animals, however, plant organisms show large scale integration in their structure and function. In higher plants, such as in animals, the intercellular communication is fulfilled through chemical messengers. These specific compounds in plants are called phytohormones, or in a wide sense, bioregulators. Even a small quantity of these endogenous organic compounds are able to regulate the operation, growth and development of higher plants, and keep the connection between cells, tissues and synergy between organs. Since they do not have nervous and immume systems, phytohormones play essential role in plants' life.

  1. Hormonal changes in antiorthostatic rats

    NASA Technical Reports Server (NTRS)

    Popovic, V.; Popovic, P.; Honeycutt, C.

    1982-01-01

    Hypokinesia, especially hypokinesia with negative tilt ('antiorthostatic hypokinesia'), mimics some of the effects of weightlessness. It is shown that cardiac output is increased during early exposure of rats to antiorthostatic hypokinesia. The increase of the stroke volume and of the cardiac output observed in the antiorthostatic hypokinetic rats is probably the consequence of a blood volume shift toward the chest brought forth by head-down positioning of the animals. It is also possible that struggling of the animals to escape from the harness and an increased metabolism contribute to the elevation of cardiac output. In order to study this hypothesis 'stress hormones' were measured in the antiorthostatic rats. Plasma levels of ACTH, corticosterone and prolactin were measured in the arterial blood (0.3 ml) sampled before, during and after hypokinesia from chronic aortic cannulas of the rats.

  2. [Plant hormones, plant growth regulators].

    PubMed

    Végvári, György; Vidéki, Edina

    2014-06-29

    Plants seem to be rather defenceless, they are unable to do motion, have no nervous system or immune system unlike animals. Besides this, plants do have hormones, though these substances are produced not in glands. In view of their complexity they lagged behind animals, however, plant organisms show large scale integration in their structure and function. In higher plants, such as in animals, the intercellular communication is fulfilled through chemical messengers. These specific compounds in plants are called phytohormones, or in a wide sense, bioregulators. Even a small quantity of these endogenous organic compounds are able to regulate the operation, growth and development of higher plants, and keep the connection between cells, tissues and synergy between organs. Since they do not have nervous and immume systems, phytohormones play essential role in plants' life. PMID:24954142

  3. Growth hormone doping: a review

    PubMed Central

    Erotokritou-Mulligan, Ioulietta; Holt, Richard IG; Sönksen, Peter H

    2011-01-01

    The use of growth hormone (GH) as a performance enhancing substance was first promoted in lay publications, long before scientists fully acknowledged its benefits. It is thought athletes currently use GH to enhance their athletic performance and to accelerate the healing of sporting injuries. Over recent years, a number of high profile athletes have admitted to using GH. To date, there is only limited and weak evidence for its beneficial effects on performance. Nevertheless the “hype” around its effectiveness and the lack of a foolproof detection methodology that will detect its abuse longer than 24 hours after the last injection has encouraged its widespread use. This article reviews the current evidence of the ergogenic effects of GH along with the risks associated with its use. The review also examines methodologies, both currently available and in development for detecting its abuse. PMID:24198576

  4. Thyroid hormones, learning and memory.

    PubMed

    Rivas, M; Naranjo, J R

    2007-06-01

    Thyroid hormones (THs), T3 and T4, have many physiological actions and are essential for normal behavioral, intellectual and neurological development. THs have a broad spectrum of effects on the developing brain and mediate important effects within the CNS throughout life. Insufficient maternal iodine intake during gestation and TH deficiency during human development are associated to pathological alterations such as cretinism and mental retardation. In adulthood, thyroid dysfunction is related to neurological and behavioral abnormalities, including memory impairment. Analysis of different experimental models suggests that most of the effects on cognition as a result of thyroid dysfunction rely on hippocampal modifications. Insufficiency of THs during development thus alters hippocampal synaptic function and impairs behavioral performance of hippocampal-dependent learning and memory tasks that persist in euthyroid adult animals. In the present review, we summarize the current knowledge obtained by clinical observations and experimental models that shows the importance of THs in learning and mnemonic processes. PMID:17543038

  5. Daily regulation of hormone profiles.

    PubMed

    Kalsbeek, Andries; Fliers, Eric

    2013-01-01

    The highly coordinated output of the hypothalamic biological clock does not only govern the daily rhythm in sleep/wake (or feeding/fasting) behaviour but also has direct control over many aspects of hormone release. In fact, a significant proportion of our current understanding of the circadian clock has its roots in the study of the intimate connections between the hypothalamic clock and multiple endocrine axes. This chapter will focus on the anatomical connections used by the mammalian biological clock to enforce its endogenous rhythmicity on the rest of the body, using a number of different hormone systems as a representative example. Experimental studies have revealed a highly specialised organisation of the connections between the mammalian circadian clock neurons and neuroendocrine as well as pre-autonomic neurons in the hypothalamus. These complex connections ensure a logical coordination between behavioural, endocrine and metabolic functions that will help the organism adjust to the time of day most efficiently. For example, activation of the orexin system by the hypothalamic biological clock at the start of the active phase not only ensures that we wake up on time but also that our glucose metabolism and cardiovascular system are prepared for this increased activity. Nevertheless, it is very likely that the circadian clock present within the endocrine glands plays a significant role as well, for instance, by altering these glands' sensitivity to specific stimuli throughout the day. In this way the net result of the activity of the hypothalamic and peripheral clocks ensures an optimal endocrine adaptation of the metabolism of the organism to its time-structured environment. PMID:23604480

  6. Adipose tissues and thyroid hormones

    PubMed Central

    Obregon, Maria-Jesus

    2014-01-01

    The maintenance of energy balance is regulated by complex homeostatic mechanisms, including those emanating from adipose tissue. The main function of the adipose tissue is to store the excess of metabolic energy in the form of fat. The energy stored as fat can be mobilized during periods of energy deprivation (hunger, fasting, diseases). The adipose tissue has also a homeostatic role regulating energy balance and functioning as endocrine organ that secretes substances that control body homeostasis. Two adipose tissues have been identified: white and brown adipose tissues (WAT and BAT) with different phenotype, function and regulation. WAT stores energy, while BAT dissipates energy as heat. Brown and white adipocytes have different ontogenetic origin and lineage and specific markers of WAT and BAT have been identified. “Brite” or beige adipose tissue has been identified in WAT with some properties of BAT. Thyroid hormones exert pleiotropic actions, regulating the differentiation process in many tissues including the adipose tissue. Adipogenesis gives raise to mature adipocytes and is regulated by several transcription factors (c/EBPs, PPARs) that coordinately activate specific genes, resulting in the adipocyte phenotype. T3 regulates several genes involved in lipid mobilization and storage and in thermogenesis. Both WAT and BAT are targets of thyroid hormones, which regulate genes crucial for their proper function: lipogenesis, lipolysis, thermogenesis, mitochondrial function, transcription factors, the availability of nutrients. T3 acts directly through specific TREs in the gene promoters, regulating transcription factors. The deiodinases D3, D2, and D1 regulate the availability of T3. D3 is activated during proliferation, while D2 is linked to the adipocyte differentiation program, providing T3 needed for lipogenesis and thermogenesis. We examine the differences between BAT, WAT and brite/beige adipocytes and the process that lead to activation of UCP1 in WAT

  7. Antifertility effects of luteinizing hormone-releasing hormone (LHRH) agonists.

    PubMed

    Labrie, F; Bélanger, A; Kelly, P A; Séguin, C; Cusan, L; Lefebvre, F A; Reeves, J J; Lemay, A; Faure, N; Gourdeau, Y; Raynaud, J P

    1981-01-01

    This paper reviews the mechanisms responsible for the antifertility effects of luteinizing hormone-releasing hormone (LHRH) agonists. Large doses of the LHRH agonist LHRH-EA lead to a marked reduction of testicular and secondary sex organ weight, LH receptor levels, and plasma testosterone concentration. A marked inhibition of basal testicular and testosterone concentrations is obtained after daily administration of the LHRH agonists at doses greater than 10 ng. Treatment with low doses of the LHRH agonist can lead to an increased steroidogenic response to LH. Treatment with low doses of LHRH agonists could stimulate Leydig cell function while high doses are history. A study of the effects of longterm treatment with an LHRH agonsist on spermatogenesis revelaed that testis, prostate, and seminal vesicle weight decreased and plasma LH and FSH levels increased over 12 weeks. Comparison of the effects of increasing doses of LHRH agonist on testicular and ovarian gonadotropin receptors and steroidogenesis in male rats indicates that single or repeated administration of LHRH agonists can lead to loss of testicular LH receptors in the absence of the pituitary gland. The loss of ovarian gonadotropin receptors in female rats is also investigated. Antifertility effects of LHRH ethylamide are accompanied by a marked loss of LH/hCG and FSH receptors in ovarian tissue. The injection of 1,3, or 10 ng LHRH-EA in intact rats has no significant effect on ovarian LH receptor levels. A study of the direct action of LHRH agonists at the ovarian level demonstrates a close relationship between the binding activity of a large series of LHRH agonists and antagonists in the anterior pituitary gland and the ovary. Inhibition of testicular steroidogenesis in man by treatment with a potent LHRH agonist is also demonstrated. Intranasal administration of LHRH ethylamide has luteolytic effects in normal women. Daily administration of LHRH-EA inhibited ovulation in all but 2 of 89 treatment

  8. Analogues of luteinizing hormone-releasing hormone containing cytotoxic groups.

    PubMed Central

    Janáky, T; Juhász, A; Bajusz, S; Csernus, V; Srkalovic, G; Bokser, L; Milovanovic, S; Redding, T W; Rékási, Z; Nagy, A

    1992-01-01

    In an attempt to produce better cytotoxic analogues, chemotherapeutic antineoplastic radicals including an alkylating nitrogen mustard derivative of D-phenylalanine (D-melphalan), reactive cyclopropane, anthraquinone derivatives [2-(hydroxymethyl)anthraquinone and the anticancer antibiotic doxorubicin], and an antimetabolite (methotrexate) were coupled to suitably modified agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH). Analogues with D-lysine6 and D-ornithine6 or N epsilon-(2,3-diaminopropionyl)-D-lysine and N delta-(2,3-diaminopropionyl)-D-ornithine were used as carriers for one or two cytotoxic moieties. The enhanced biological activities produced by the incorporation of D amino acids into position 6 of the agonistic analogues were further increased by the attachment of hydrophobic cytotoxic groups, resulting in compounds with 10-50 times higher activity than LH-RH. Most of the monosubstituted agonistic analogues showed high affinities for the membrane receptors of human breast cancer cells, while the receptor binding affinities of peptides containing two cytotoxic side chains were lower. Antagonistic carriers [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,D-Lys6,D-Ala10] LH-RH [where Nal(2) is 3-(2-naphthyl)alanine], [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,N epsilon-(2,3-diaminopropionyl)-D-Lys6,D-Ala10]LH-RH, and their D-Pal(3)3 homologs [Pal(3) is 3-(3-pyridyl)alanine] as well as [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Pal(3)3,Tyr5,N epsilon-(2,3-diamino-propionyl)-D-Lys6,D-Ala10]LH-RH were linked to cytotoxic compounds. The hybrid molecules inhibited ovulation in rats at doses of 10 micrograms and suppressed LH release in vitro. The receptor binding of cytotoxic analogues was decreased compared to the precursor peptides, although analogues with 2-(hydroxymethyl)anthraquinone hemiglutarate had high affinities. All of the cytotoxic analogues tested inhibited [3H]thymidine incorporation into DNA in cultures of human breast and prostate cancer cell lines

  9. Effects of hormones on lipids and lipoproteins

    SciTech Connect

    Krauss, R.M.

    1991-12-01

    Levels of plasma lipids and lipoproteins are strong predictors for the development of atherosclerotic cardiovascular disease in postmenopausal women. In women, as in men, numerous factors contribute to variations in plasma lipoproteins that may affect cardiovascular disease risk. These include age, dietary components, adiposity, genetic traits, and hormonal changes. Each of these factors may operate to varying degrees in determining changes in plasma lipoprotein profiles accompanying menopause- Cross-sectional and longitudinal studies have suggested increases in levels of cholesterol, low density lipoproteins (LDL) and triglyceride-rich lipoproteins associated with menopause. High density lipoproteins (HDL), which are higher in women than men and are thought to contribute to relative protection of premenopausal women from cardiovascular disease, remain relatively constant in the years following menopause, although small, and perhaps transient reductions in the HDL{sub 2} subfraction have been reported in relation to reduced estradiol level following menopause. Despite these associations, it has been difficult to determine the role of endogenous hormones in influencing the plasma lipoproteins of postmenopausal women. In principle, the effects of hormone replacement should act to reverse any alterations in lipoprotein metabolism that are due to postmenopausal hormone changes. While there may be beneficial effects on lipoproteins, hormone treatment does not restore a premenopausal lipoprotein profile. Furthermore, it is not dear to what extent exogenous hormone-induced lipoprotein changes contribute to the reduced incidence of cardiovascular disease with hormone replacement therapy.

  10. Anabolic hormone profiles in elite military men.

    PubMed

    Taylor, Marcus K; Kviatkovsky, Shiloah A; Hernández, Lisa M; Sargent, Paul; Segal, Sabrina; Granger, Douglas A

    2016-06-01

    We recently characterized the awakening responses and daily profiles of the catabolic stress hormone cortisol in elite military men. Anabolic hormones follow a similar daily pattern and may counteract the catabolic effects of cortisol. This companion report is the first to characterize daily profiles of anabolic hormones dehydroepiandrosterone (DHEA) and testosterone in this population. Overall, the men in this study displayed anabolic hormone profiles comparable to that of healthy, athletic populations. Consistent with the cortisol findings in our prior report, summary parameters of magnitude (hormone output) within the first hour after awakening displayed superior stability versus summary parameters of pattern for both DHEA (r range: 0.77-0.82) and testosterone (r range: 0.62-0.69). Summary parameters of evening function were stable for the two hormones (both p<0.001), while the absolute decrease in testosterone across the day was a stable proxy of diurnal function (p<0.001). Removal of noncompliant subjects did not appreciably affect concentration estimates for either hormone at any time point, nor did it alter the repeatability of any summary parameter. The first of its kind, this report enables accurate estimations of anabolic balance and resultant effects upon health and human performance in this highly resilient yet chronically stressed population. PMID:27083310

  11. Anabolic hormone profiles in elite military men.

    PubMed

    Taylor, Marcus K; Kviatkovsky, Shiloah A; Hernández, Lisa M; Sargent, Paul; Segal, Sabrina; Granger, Douglas A

    2016-06-01

    We recently characterized the awakening responses and daily profiles of the catabolic stress hormone cortisol in elite military men. Anabolic hormones follow a similar daily pattern and may counteract the catabolic effects of cortisol. This companion report is the first to characterize daily profiles of anabolic hormones dehydroepiandrosterone (DHEA) and testosterone in this population. Overall, the men in this study displayed anabolic hormone profiles comparable to that of healthy, athletic populations. Consistent with the cortisol findings in our prior report, summary parameters of magnitude (hormone output) within the first hour after awakening displayed superior stability versus summary parameters of pattern for both DHEA (r range: 0.77-0.82) and testosterone (r range: 0.62-0.69). Summary parameters of evening function were stable for the two hormones (both p<0.001), while the absolute decrease in testosterone across the day was a stable proxy of diurnal function (p<0.001). Removal of noncompliant subjects did not appreciably affect concentration estimates for either hormone at any time point, nor did it alter the repeatability of any summary parameter. The first of its kind, this report enables accurate estimations of anabolic balance and resultant effects upon health and human performance in this highly resilient yet chronically stressed population.

  12. Hormonal Factors and Disturbances in Eating Disorders.

    PubMed

    Culbert, Kristen M; Racine, Sarah E; Klump, Kelly L

    2016-07-01

    This review summarizes the current state of the literature regarding hormonal correlates of, and etiologic influences on, eating pathology. Several hormones (e.g., ghrelin, CCK, GLP-1, PYY, leptin, oxytocin, cortisol) are disrupted during the ill state of eating disorders and likely contribute to the maintenance of core symptoms (e.g., dietary restriction, binge eating) and/or co-occurring features (e.g., mood symptoms, attentional biases). Some of these hormones (e.g., ghrelin, cortisol) may also be related to eating pathology via links with psychological stress. Despite these effects, the role of hormonal factors in the etiology of eating disorders remains unknown. The strongest evidence for etiologic effects has emerged for ovarian hormones, as changes in ovarian hormones predict changes in phenotypic and genetic influences on disordered eating. Future studies would benefit from utilizing etiologically informative designs (e.g., high risk, behavioral genetic) and continuing to explore factors (e.g., psychological, neural responsivity) that may impact hormonal influences on eating pathology. PMID:27222139

  13. Hormonal Factors and Disturbances in Eating Disorders.

    PubMed

    Culbert, Kristen M; Racine, Sarah E; Klump, Kelly L

    2016-07-01

    This review summarizes the current state of the literature regarding hormonal correlates of, and etiologic influences on, eating pathology. Several hormones (e.g., ghrelin, CCK, GLP-1, PYY, leptin, oxytocin, cortisol) are disrupted during the ill state of eating disorders and likely contribute to the maintenance of core symptoms (e.g., dietary restriction, binge eating) and/or co-occurring features (e.g., mood symptoms, attentional biases). Some of these hormones (e.g., ghrelin, cortisol) may also be related to eating pathology via links with psychological stress. Despite these effects, the role of hormonal factors in the etiology of eating disorders remains unknown. The strongest evidence for etiologic effects has emerged for ovarian hormones, as changes in ovarian hormones predict changes in phenotypic and genetic influences on disordered eating. Future studies would benefit from utilizing etiologically informative designs (e.g., high risk, behavioral genetic) and continuing to explore factors (e.g., psychological, neural responsivity) that may impact hormonal influences on eating pathology.

  14. Arabidopsis Hormone Database: a comprehensive genetic and phenotypic information database for plant hormone research in Arabidopsis.

    PubMed

    Peng, Zhi-yu; Zhou, Xin; Li, Linchuan; Yu, Xiangchun; Li, Hongjiang; Jiang, Zhiqiang; Cao, Guangyu; Bai, Mingyi; Wang, Xingchun; Jiang, Caifu; Lu, Haibin; Hou, Xianhui; Qu, Lijia; Wang, Zhiyong; Zuo, Jianru; Fu, Xiangdong; Su, Zhen; Li, Songgang; Guo, Hongwei

    2009-01-01

    Plant hormones are small organic molecules that influence almost every aspect of plant growth and development. Genetic and molecular studies have revealed a large number of genes that are involved in responses to numerous plant hormones, including auxin, gibberellin, cytokinin, abscisic acid, ethylene, jasmonic acid, salicylic acid, and brassinosteroid. Here, we develop an Arabidopsis hormone database, which aims to provide a systematic and comprehensive view of genes participating in plant hormonal regulation, as well as morphological phenotypes controlled by plant hormones. Based on data from mutant studies, transgenic analysis and gene ontology (GO) annotation, we have identified a total of 1026 genes in the Arabidopsis genome that participate in plant hormone functions. Meanwhile, a phenotype ontology is developed to precisely describe myriad hormone-regulated morphological processes with standardized vocabularies. A web interface (http://ahd.cbi.pku.edu.cn) would allow users to quickly get access to information about these hormone-related genes, including sequences, functional category, mutant information, phenotypic description, microarray data and linked publications. Several applications of this database in studying plant hormonal regulation and hormone cross-talk will be presented and discussed.

  15. Arabidopsis Hormone Database: a comprehensive genetic and phenotypic information database for plant hormone research in Arabidopsis.

    PubMed

    Peng, Zhi-yu; Zhou, Xin; Li, Linchuan; Yu, Xiangchun; Li, Hongjiang; Jiang, Zhiqiang; Cao, Guangyu; Bai, Mingyi; Wang, Xingchun; Jiang, Caifu; Lu, Haibin; Hou, Xianhui; Qu, Lijia; Wang, Zhiyong; Zuo, Jianru; Fu, Xiangdong; Su, Zhen; Li, Songgang; Guo, Hongwei

    2009-01-01

    Plant hormones are small organic molecules that influence almost every aspect of plant growth and development. Genetic and molecular studies have revealed a large number of genes that are involved in responses to numerous plant hormones, including auxin, gibberellin, cytokinin, abscisic acid, ethylene, jasmonic acid, salicylic acid, and brassinosteroid. Here, we develop an Arabidopsis hormone database, which aims to provide a systematic and comprehensive view of genes participating in plant hormonal regulation, as well as morphological phenotypes controlled by plant hormones. Based on data from mutant studies, transgenic analysis and gene ontology (GO) annotation, we have identified a total of 1026 genes in the Arabidopsis genome that participate in plant hormone functions. Meanwhile, a phenotype ontology is developed to precisely describe myriad hormone-regulated morphological processes with standardized vocabularies. A web interface (http://ahd.cbi.pku.edu.cn) would allow users to quickly get access to information about these hormone-related genes, including sequences, functional category, mutant information, phenotypic description, microarray data and linked publications. Several applications of this database in studying plant hormonal regulation and hormone cross-talk will be presented and discussed. PMID:19015126

  16. The Radioimmunoassay of Fluid and Electrolyte Hormones

    NASA Technical Reports Server (NTRS)

    Keil, Lanny C.

    1985-01-01

    The subject of the paper will be the assay of fluid/electrolyte hormones. ADH (antidiuretic hormone also referred to as vasopressin) reduces fluid loss by increasing water reabsorption by the kidney. The stimuli for its release from the pituitary are loss of blood, dehydration, or increased salt intake. Angiotensin II is the next hormone of interest. It is "generated" from a blood protein by the release of renin from the kidney. One of its functions is to stimulate the secretion of aldosterone from the adrenal gland. Release of renin is also stimulated by volume and sodium loss.

  17. Hormonal component of tumor photodynamic therapy response

    NASA Astrophysics Data System (ADS)

    Korbelik, Mladen; Merchant, Soroush

    2008-02-01

    The involvement of adrenal glucocorticoid hormones in the response of the treatment of solid tumors by photodynamic therapy (PDT) comes from the induction of acute phase response by this modality. This adrenal gland activity is orchestrated through the engagement of the hypothalamic-pituitary-adrenal hormonal axis incited by stress signals emanating from the PDT-treated tumor. Glucocorticoid hormone activity engendered within the context of PDT-induced acute phase response performs multiple important functions; among other involvements they beget acute phase reactant production, systemic neutrophil mobilization, and control the production of inflammation-modulating and immunoregulatory proteins.

  18. Obtaining growth hormone from calf blood

    NASA Technical Reports Server (NTRS)

    Kalchev, L. A.; Ralchev, K. K.; Nikolov, I. T.

    1979-01-01

    The preparation of a growth hormone from human serum was used for the isolation of the hormone from calf serum. The preparation was biologically active - it increased the quantity of the free fatty acids released in rat plasma by 36.4 percent. Electrophoresis in Veronal buffer, ph 8.6, showed the presence of a single fraction having mobility intermediate between that of alpha and beta globulins. Gel filtration through Sephadex G 100 showed an elutriation curve identical to that obtained by the growth hormone prepared from pituitary glands.

  19. Pituitary and placental hormone levels in pseudocyesis.

    PubMed

    Osotimehin, B O; Ladipo, O A; Adejuwon, C A; Otolorin, E O

    1981-10-01

    Twelve patients with clinical features of pseudocyesis were divided into two groups according to the presence or absence of galactorrhea. The mean serum prolactin level of patients with galactorrhea was significantly higher than the normal values of the patients without galactorrhea. The mean serum levels of luteinizing hormone and follicle-stimulating hormone were markedly elevated in patients without galactorrhea. This was especially true of luteinizing hormone. Serum levels of human chorionic gonadotropin were undetectable in all patients. The significance of these observations is discussed.

  20. Growth hormone insensitivity syndrome: unusual oral manifestations.

    PubMed

    Borges, Alvaro Henrique; Siqueira, Carlos Rodrigo Barros; Pedro, Fábio Luis Miranda; Palma, Vinícius Canavarros; Sakai, Vivien Thiemy; Volpato, Luiz Evaristo Ricci

    2013-01-01

    Children with significant growth retardation and normal levels of growth hormone are diagnosed with growth hormone insensitivity. The main oral findings observed in patients with growth hormone insensitivity syndrome (GHIS) are underdeveloped jaws, crowded teeth and delayed eruption of permanent teeth. This manuscript describes a 9-year-old child diagnosed with GHIS, who had delayed eruption of permanent teeth and 14 unerupted supernumerary teeth. All supernumerary teeth were extracted except for two maxillary and one mandibular teeth which were difficult to identify and access. Multiple supernumerary teeth have never been reported before in patients with GHIS.

  1. Luteinizing hormone and follicle stimulating hormone-releasing hormone test in patients with hypothalamic-pituitary-gonadal dysfunction.

    PubMed

    Mortimer, C H; Besser, G M; McNeilly, A S; Marshall, J C; Harsoulis, P; Tunbridge, W M; Gomez-Pan, A; Hall, R

    1973-10-13

    A standard intravenous 100 mug luteinizing hormone/follicle stimulating hormone-releasing hormone (LH/FSH-RH) test was used to assess the pituitary gonadotrophin responses in 155 patients with a variety of diseases of the hypothalamic-pituitary-gonadal axis. In all but nine patients there was an increase in circulating levels of either LH or FSH in response to the releasing hormone though 137 (88%) were clinically hypogonadal. It was not possible with this test to distinguish between hypothalamic and pituitary causes of hypogonadotrophic hypogonadism, since a variety of LH and FSH responses emerged within the disease groups. However, primary gonadal failure characteristically resulted in exaggerated gonadotrophin response. The potential therapeutic use of the gonadotrophin releasing decapeptide is suggested in certain patients with hypogonadotrophic hypogonadism.

  2. Calcium calmodulin and hormone secretion.

    PubMed

    Brown, B L; Walker, S W; Tomlinson, S

    1985-08-01

    As long ago as 1970, it was proposed that Ca2+ can act as a 'second messenger' like cAMP (Rasmussen & Nagata, 1979). The recognition that calmodulin is a major Ca2+ binding protein in non-muscle cells has prompted the suggestion that calmodulin may serve an analogous role for Ca2+ to that served by protein kinase for cAMP (Wang & Waisman, 1979), or at least to the regulatory subunit of the cyclic nucleotide-dependent kinases. It is becoming clear that calmodulin probably does play a role in stimulus secretion coupling in endocrine cells. Nevertheless, some of the experimental approaches which have led to this rather tentative conclusion do induce some doubts, as we have attempted to indicate. Many of the pharmacological agents used in the studies cited in this review are not specific in their interaction with calmodulin. For example, the phenothiazines also inhibit phospholipid-sensitive protein kinase. The introduction of more specific drugs, such as the naphthalene sulphonamides, may lead to a clearer picture of the role of calmodulin in hormone secretion. Relationships probably exist between cyclic nucleotides, calcium, calmodulin, phosphatidylinositol (PI) turnover and phospholipids in the overall control of the secretory process (see Fig. 1). There is considerable evidence that calcium is the primary internal signal initiating exocytosis of hormone from many glands. However, it appears that cyclic nucleotides can modulate the calcium signal either positively or negatively and it is possible that cAMP and calcium can separately activate secretion. The presence of both calmodulin-activated adenylate cyclase and cyclic nucleotide phosphodiesterase in the same tissue would appear to suggest either spatial or temporal control mechanisms or that (diagram; see text) the calcium requirement for calmodulin activation differs between the two enzymes. The true explanation is probably far more complex and involves perhaps as yet unknown factors that can differentially

  3. History of growth hormone therapy.

    PubMed

    Blizzard, Robert M

    2012-01-01

    The first human to receive GH therapy was in 1956; it was of bovine origin and was given for 3 wk for metabolic balance studies revealing no effects. By 1958, three separate laboratories utilizing different extraction methods retrieved hGH from human pituitaries, purified it and used for clinical investigation. By 1959 presumed GHD patients were being given native hGH collected and extracted by various methods. Since 1 mg of hGH was needed to treat one patient per day, >360 human pituitaries were needed per patient per year. Thus, the availability of hGH was limited and was awarded on the basis of clinical research protocols approved by the National Pituitary Agency (NPA) established in 1961. hGH was dispensed and injected on a milligram weight basis with varied concentrations between batches from 0.5 units/mg to 2.0 units/mg of hGH. By 1977 a centralized laboratory was established to extract all human pituitaries in the US, this markedly improved the yield of hGH obtained and most remarkably, hGH of this laboratory was never associated with Creutzfeld-Jacob disease (CJD) resulting from the injection of apparently prior- contaminated hGH produced years earlier. However, widespread rhGH use was not possible even if a pituitary from each autopsy performed in the US was collected, this would only permit therapy for about 4,000 patients. Thus, the mass production of rhGH required the identification of the gene structure of the hormone, methodology that began in 1976 to make insulin by recombinant technology. Serendipity was manifest in 1985 when patients who had received hGH years previously were reported to have died of CJD. This led to the discontinuation of the distribution and use of hGH, at a time when a synthetic rhGH became available for clinical use. The creation of a synthetic rhGH was accompanied by unlimited supplies of hGH for investigation and therapy. However, the appropriate use and the potential abuse of this hormone are to be dealt with. The

  4. Sex steroids modulate luteinizing hormone-releasing hormone secretion in a cholinergic cell line from the basal forebrain.

    PubMed

    Martínez-Morales, J R; López-Coviella, I; Hernández-Jiménez, J G; Reyes, R; Bello, A R; Hernández, G; Blusztajn, J K; Alonso, R

    2001-01-01

    The function of a particular neuronal population is in part determined by its neurotransmitter phenotype. We have found that a neuronal-derived septal cell line (SN56), known for its cholinergic properties, also synthesizes and releases luteinizing hormone-releasing hormone. In addition, these cells express the messenger RNAs encoding estrogen and progesterone receptors. The activation of these receptors by their respective ligands cooperatively modulates the depolarization-induced release of luteinizing hormone-releasing hormone in these cells. We have also found that a number of septal neurons in postnatal (1-week-old) mice are immunoreactive to both choline acetyltransferase and luteinizing hormone-releasing hormone. These results indicate that both neurotransmitters, acetylcholine and luteinizing hormone-releasing hormone, may co-exist in septal neurons of the CNS and that they could be modulated by gonadal hormones, and suggest that luteinizing hormone-releasing hormone could be involved in some of the actions of sex steroids on cholinergic neurotransmission.

  5. Thyroid Hormone and Seasonal Rhythmicity

    PubMed Central

    Dardente, Hugues; Hazlerigg, David G.; Ebling, Francis J. P.

    2014-01-01

    Living organisms show seasonality in a wide array of functions such as reproduction, fattening, hibernation, and migration. At temperate latitudes, changes in photoperiod maintain the alignment of annual rhythms with predictable changes in the environment. The appropriate physiological response to changing photoperiod in mammals requires retinal detection of light and pineal secretion of melatonin, but extraretinal detection of light occurs in birds. A common mechanism across all vertebrates is that these photoperiod-regulated systems alter hypothalamic thyroid hormone (TH) conversion. Here, we review the evidence that a circadian clock within the pars tuberalis of the adenohypophysis links photoperiod decoding to local changes of TH signaling within the medio-basal hypothalamus (MBH) through a conserved thyrotropin/deiodinase axis. We also focus on recent findings which indicate that, beyond the photoperiodic control of its conversion, TH might also be involved in longer-term timing processes of seasonal programs. Finally, we examine the potential implication of kisspeptin and RFRP3, two RF-amide peptides expressed within the MBH, in seasonal rhythmicity. PMID:24616714

  6. Development of growth hormone secretagogues.

    PubMed

    Smith, Roy G

    2005-05-01

    The GH secretagogues (GHS) were developed by reverse pharmacology. The objective was to develop small molecules with pharmacokinetics suitable for once-daily oral administration that would rejuvenate the GH/IGF-I axis. Neither the receptor nor the ligand that controlled pulse amplitude of hormone release was known; therefore, identification of lead structures was based on function. I reasoned that GH pulse amplitude could be increased by four possible mechanisms: 1) increasing GHRH release; 2) amplifying GHRH signaling in somatotrophs of the anterior pituitary gland; 3) reducing somatostatin release; and 4) antagonizing somatostatin receptor signaling. Remarkably, the GHS act through all four mechanisms to reproduce a young adult physiological GH profile in elderly subjects that was accompanied by increased bone mineral density and lean mass, modest improvements in strength, and improved recovery from hip fracture. Furthermore, restoration of thymic function was induced in old mice. The GHS receptor (GHS-R) was subsequently identified by expression cloning and found to be a previously unknown G protein-coupled receptor expressed predominantly in brain, pituitary gland, and pancreas. Reverse pharmacology was completed when the cloned GHS-R was exploited to identify an endogenous agonist (ghrelin) and a partial agonist (adenosine); ghsr-knockout mice studies confirmed that GHS are ghrelin mimetics. PMID:15814848

  7. Neuroendocrine hormone amylin in diabetes.

    PubMed

    Zhang, Xiao-Xi; Pan, Yan-Hong; Huang, Yan-Mei; Zhao, Hai-Lu

    2016-05-10

    The neuroendocrine hormone amylin, also known as islet amyloid polypeptide, is co-localized, co-packaged and co-secreted with insulin from adult pancreatic islet β cells to maintain glucose homeostasis. Specifically, amylin reduces secretion of nutrient-stimulated glucagon, regulates blood pressure with an effect on renin-angiotensin system, and delays gastric emptying. The physiological actions of human amylin attribute to the conformational α-helix monomers whereas the misfolding instable oligomers may be detrimental to the islet β cells and further transform to β-sheet fibrils as amyloid deposits. No direct evidence proves that the amylin fibrils in amyloid deposits cause diabetes. Here we also have performed a systematic review of human amylin gene changes and reported the S20G mutation is minor in the development of diabetes. In addition to the metabolic effects, human amylin may modulate autoimmunity and innate inflammation through regulatory T cells to impact on both human type 1 and type 2 diabetes. PMID:27162583

  8. [Neuroendocrine effect of sex hormones].

    PubMed

    Babichev, V N

    2005-01-01

    The paper provides a generalization of data and the results of own experiments on influence ovarian steroids on the hypothalamus and other brain areas related to reproduction. Ovarian hormones have widespread effects throughout the brain: on catecholaminergic neurons and serotonergic pathways and the basal forebrain cholinergic system, as well as the hipocampus, spinal cord, nigrostriatal and mesolimbic system, in addition to glial cells and blood-brain barrier. The widespread influences of these various neuronal systems ovarian steroids have measurable effects on mood and affect as well as on cognition, with implications for dementia. There are developmentally programmed sex differenced in hippocampal structure that may help to explain differences in the strategies which male and female rats use to solve spatial navigation problems. The multiple sites and mechanisms of estrogen action in brain underlie a variety of importants effects on cognitive and other brain functions--coordination of movement, pain, affective state, as well as possible protection in Alzheimer's disease. Estrogen withdrawal after natural or surgical menopause can lead to a host of changes in brain function and behavior.

  9. Extrapituitary growth hormone and growth?

    PubMed

    Harvey, Steve; Baudet, Marie-Laure

    2014-09-01

    While growth hormone (GH) is obligatory for postnatal growth, it is not required for a number of growth-without-GH syndromes, such as early embryonic or fetal growth. Instead, these syndromes are thought to be dependent upon local growth factors, rather than pituitary GH. The GH gene is, however, also expressed in many extrapituitary tissues, particularly during early development and extrapituitary GH may be one of the local growth factors responsible for embryonic or fetal growth. Moreover, as the expression of the GH receptor (GHR) gene mirrors that of GH in extrapituitary tissues the actions of GH in early development are likely to be mediated by local autocrine or paracrine mechanisms, especially as extrapituitary GH expression occurs prior to the ontogeny of pituitary somatotrophs or the appearance of GH in the circulation. The extrapituitary expression of pituitary somatotrophs or the appearance of GH in the circulation. The extrapituitary expression of GH in embryos has also been shown to be of functional relevance in a number of species, since the immunoneutralization of endogenous GH or the blockade of GH production is accompanied by growth impairment or cellular apoptosis. The extrapituitary expression of the GH gene also persists in some central and peripheral tissues postnatally, which may reflect its continued functional importance and physiological or pathophysiological significance. The expression and functional relevance of extrapituitary GH, particularly during embryonic growth, is the focus of this brief review.

  10. Chemosignals, hormones, and amphibian reproduction.

    PubMed

    Woodley, Sarah

    2015-02-01

    This article is part of a Special Issue "Chemosignals and Reproduction". Amphibians are often thought of as relatively simple animals especially when compared to mammals. Yet the chemosignaling systems used by amphibians are varied and complex. Amphibian chemosignals are particularly important in reproduction, in both aquatic and terrestrial environments. Chemosignaling is most evident in salamanders and newts, but increasing evidence indicates that chemical communication facilitates reproduction in frogs and toads as well. Reproductive hormones shape the production, dissemination, detection, and responsiveness to chemosignals. A large variety of chemosignals have been identified, ranging from simple, invariant chemosignals to complex, variable blends of chemosignals. Although some chemosignals elicit straightforward responses, others have relatively subtle effects. Review of amphibian chemosignaling reveals a number of issues to be resolved, including: 1) the significance of the complex, individually variable blends of courtship chemosignals found in some salamanders, 2) the behavioral and/or physiological functions of chemosignals found in anuran "breeding glands", 3) the ligands for amphibian V2Rs, especially V2Rs expressed in the main olfactory epithelium, and 4) the mechanism whereby transdermal delivery of chemosignals influences behavior. To date, only a handful of the more than 7000 species of amphibians has been examined. Further study of amphibians should provide additional insight to the role of chemosignals in reproduction.

  11. Thyroid hormones and renin secretion.

    PubMed

    Ganong, W F

    Circulating angiotensin is produced by the action of renin from the kidneys on circulating angiotensinogen. There are other renin-angiotensin systems in various organs in the body, and recent observations raise the intriguing possibility that angiotensin II is produced by a totally intracellular pathway in the juxtaglomerular cells, the gonadotrops of the anterior pituitary, neurons, in the brain, salivary duct cells, and neuroblastoma cells. Circulating angiotensin II levels depend in large part on the plasma concentration of angiotensinogen, which is hormonally regulated, and on the rate of renin secretion. Renin secretion is regulated by an intrarenal baroreceptor mechanism, a macula densa mechanism, angiotensin II, vasopressin, and the sympathetic nervous system. The increase in renin secretion produced by sympathetic discharge is mediated for the most part by beta-adrenergic receptors, which are probably located on the juxtaglomerular cells. Hyperthyroidism would be expected to be associated with increased renin secretion in view of the increased beta-adrenergic activity in this condition, and hypothyroidism would be associated with decreased plasma renin activity due to decreased beta-adrenergic activity. Our recent research on serotonin-mediated increases in renin secretion that depend on the integrity of the dorsal raphe nucleus and the mediobasal hypothalamus has led us to investigate the effect of the pituitary on the renin response to p-chloroamphetamine. The response is potentiated immediately after hypophysectomy, but 22 days after the operation, it is abolished. This slowly developing decrease in responsiveness may be due to decreased thyroid function.

  12. Silent pituitary macroadenoma co-secreting growth hormone and thyroid stimulating hormone.

    PubMed

    Sen, Orhan; Ertorer, M Eda; Aydin, M Volkan; Erdogan, Bulent; Altinors, Nur; Zorludemir, Suzan; Guvener, Nilgun

    2005-04-01

    Silent pituitary adenomas are a group of tumors showing heterogenous morphological features with no hormonal function observed clinically. To date no explanation has been provided as to why these tumors remain "silent". We report a case of a silent macroadenoma with both growth hormone (GH) and thyroid stimulating hormone (TSH) staining and secretion but with no clinical manifestations, in particular, the absence of features of acromegaly or hyperthyroidism. The relevant literature is reviewed. PMID:15851094

  13. Thyroid hormone, brain development, and the environment.

    PubMed Central

    Zoeller, Thomas R; Dowling, Amy L S; Herzig, Carolyn T A; Iannacone, Eric A; Gauger, Kelly J; Bansal, Ruby

    2002-01-01

    Thyroid hormone is essential for normal brain development. Therefore, it is a genuine concern that thyroid function can be altered by a very large number of chemicals routinely found in the environment and in samples of human and wildlife tissues. These chemicals range from natural to manufactured compounds. They can produce thyroid dysfunction when they are absent from the diet, as in the case of iodine, or when they are present in the diet, as in the case of thionamides. Recent clinical evidence strongly suggests that brain development is much more sensitive to thyroid hormone excess or deficit than previously believed. In addition, recent experimental research provides new insight into the developmental processes affected by thyroid hormone. Based on the authors' research focusing on the ability of polychlorinated biphenyls to alter the expression of thyroid hormone-responsive genes in the developing brain, this review provides background information supporting a new way of approaching risk analysis of thyroid disruptors. PMID:12060829

  14. Hormonal and biochemical responses to transcendental meditation.

    PubMed

    Cooper, R; Joffe, B I; Lamprey, J M; Botha, A; Shires, R; Baker, S G; Seftel, H C

    1985-04-01

    This study was designed to assess whether transcendental meditation (TM) could influence various endocrine responses in 10 experienced male meditators. Nine matched subjects, uninformed of the TM procedure, acted as controls. Meditators successfully practised their technique for 40 min in the morning while controls relaxed for this period. No significant differences emerged between these 2 groups with respect to carbohydrate metabolism (plasma glucose, insulin and pancreatic glucagon concentrations), pituitary hormones (growth hormone and prolactin) or the 'stress' hormones, cortisol and total catecholamines-although meditators tended to have higher mean catecholamine levels. Plasma free fatty acids were significantly elevated in meditators 40 min after completing the period of TM. No clear evidence was thus obtained that any of the stress, or stress-related, hormones were suppressed during or after meditation in the particular setting examined.

  15. Genetics Home Reference: combined pituitary hormone deficiency

    MedlinePlus

    ... People with combined pituitary hormone deficiency may have hypothyroidism, which is underactivity of the butterfly-shaped thyroid gland in the lower neck. Hypothyroidism can cause many symptoms, including weight gain and ...

  16. Hormones and pregnancy: thromboembolic risks for women.

    PubMed

    Kujovich, Jody L

    2004-08-01

    During their lifetimes, women face several unique situations with an increased risk of venous thromboembolism (VTE). Doctors in a variety of specialties must advise women on the risks of oral contraceptives (OC), hormone replacement or pregnancy. Modern 'low dose' OC are associated with a three to sixfold increased relative risk of VTE. Hormone replacement and selective oestrogen receptor modulators confer a similar two to fourfold increase in thrombotic risk. However, because the baseline incidence of thrombosis is higher in older postmenopausal women, the absolute risk is higher than in younger OC users. The risk of venous thrombosis is six to 10-fold higher during pregnancy than in non-pregnant women of similar age. Thrombophilic disorders increase the thrombotic risk of OC, hormone replacement and pregnancy, especially in women with homozygous or combined defects. This review focuses on recent data estimating the thrombotic risk of hormonal therapies and pregnancy in women with and without other thrombotic risk factors.

  17. IODIDE DEFICIENCY, THYROID HORMONES, AND NEURODEVELOPMENT

    EPA Science Inventory

    ABSTRACT BODY: Iodide is an essential nutrient for thyroid hormone synthesis. Severe iodide insufficiency during early development is associated with cognitive deficits. Environmental contaminants can perturb the thyroid axis and this perturbation may be more acute under conditio...

  18. Innovations in classical hormonal targets for endometriosis.

    PubMed

    Pluchino, Nicola; Freschi, Letizia; Wenger, Jean-Marie; Streuli, Isabelle

    2016-01-01

    Endometriosis is a chronic disease of unknown etiology that affects approximately 10% of women in reproductive age. Several evidences show that endometriosis lesions are associated to hormonal imbalance, including estrogen synthesis, metabolism and responsiveness and progesterone resistance. These hormonal alterations influence the ability of endometrial cells to proliferate, migrate and to infiltrate the mesothelium, causing inflammation, pain and infertility. Hormonal imbalance in endometriosis represents also a target for treatment. We provide an overview on therapeutic strategies based on innovations of classical hormonal mechanisms involved in the development of endometriosis lesions. The development phase of new molecules targeting these pathways is also discussed. Endometriosis is a chronic disease involving young women and additional biological targets of estrogen and progesterone pharmacological manipulation (brain, bone and cardiovascular tissue) need to be carefully considered in order to improve and overcome current limits of long-term medical management of endometriosis.

  19. Hormones in the seminal plasma. Cortisol.

    PubMed

    Abbaticchio, G; Giorgino, R; Urago, M; Gattuccio, F; Orlando, G; Jannì, A

    1981-09-01

    The data from previous studies on the seminal concentrations of proteic hormones result in the hypothesis that there exists a selective filter for these hormones, which is between the systemic circulation and the male genital canal. Previous data regarding sexual steroids are insufficient to verify if such a filter system also operates in the case of hormones of minor molecular weight. It would appear that the study of cortisol, a non-sexual steroid, will be more useful. The concentrations of this hormone in the peripheric blood (176 +/- 59, mean +/- ds, ng/ml) prove to be much greater than in the seminal plasma (20 +/- 9.6). No significant differences are found between normozoospermic and oligo-azoospermic subjects, either in the blood (173 +/- 184 +/- 53), or in the seminal plasma (21 +/- 12 versus 20 +/- 8). These data would seem to support the hypothesis under discussion.

  20. Strategies for the Determination of Plant Hormones.

    ERIC Educational Resources Information Center

    Davis, Gregory C.; And Others

    1985-01-01

    Describes methods for isolating, purifying, and analyzing plant hormones (molecules involved in plant growth regulation and development). The presentation reflects the historical development of analyses, beginning with bioassays and ending with novel immunochemical assays. (JN)

  1. Male reproductive hormone profile in Rwandan students.

    PubMed

    Gahutu, J B

    2014-12-01

    To illustrate the male reproductive hormone profile, a study was conducted among healthy male university students living at Butare, Rwanda (altitude: 1 768 m, barometric pressure: 629 mm Hg). Venous blood was collected in the morning, after overnight fasting. Hormonal assays were performed by classical sandwich ELISA technique. Mean values (±standard deviation SD) were follicle-stimulating hormone FSH: 3.7 ± 1.6 IU l(-1) ; luteinising hormone LH: 3.6 ± 2.2 IU l(-1) ; and total testosterone: 21.0 ± 7.5 nm. The results compare well with findings of other studies. PMID:24313662

  2. Young addicted men hormone profile detection

    NASA Astrophysics Data System (ADS)

    Zieliński, Paweł; Wasiewicz, Piotr; Leszczyńska, Bożena; Gromadzka-Ostrowska, Joanna

    2010-09-01

    Hormone parameters were determined in the serum of young addicted men in order to compare them with those obtained from the group of healthy subjects. Three groups were investigated which were named opiates, mixed and control group. Statistical and data mining methods were applied to obtain significant differences. R package was used for all computation. The determination of hormones parameters provide important information relative to impact of addiction.

  3. Screening methods for thyroid hormone disruptors.

    PubMed Central

    DeVito, M; Biegel, L; Brouwer, A; Brown, S; Brucker-Davis, F; Cheek, A O; Christensen, R; Colborn, T; Cooke, P; Crissman, J; Crofton, K; Doerge, D; Gray, E; Hauser, P; Hurley, P; Kohn, M; Lazar, J; McMaster, S; McClain, M; McConnell, E; Meier, C; Miller, R; Tietge, J; Tyl, R

    1999-01-01

    The U.S. Congress has passed legislation requiring the EPA to implement screening tests for identifying endocrine-disrupting chemicals. A series of workshops was sponsored by the EPA, the Chemical Manufacturers Association, and the World Wildlife Fund; one workshop focused on screens for chemicals that alter thyroid hormone function and homeostasis. Participants at this meeting identified and examined methods to detect alterations in thyroid hormone synthesis, transport, and catabolism. In addition, some methods to detect chemicals that bind to the thyroid hormone receptors acting as either agonists or antagonists were also identified. Screening methods used in mammals as well as other vertebrate classes were examined. There was a general consensus that all known chemicals which interfere with thyroid hormone function and homeostasis act by either inhibiting synthesis, altering serum transport proteins, or by increasing catabolism of thyroid hormones. There are no direct data to support the assertion that certain environmental chemicals bind and activate the thyroid hormone receptors; further research is indicated. In light of this, screening methods should reflect known mechanisms of action. Most methods examined, albeit useful for mechanistic studies, were thought to be too specific and therefore would not be applicable for broad-based screening. Determination of serum thyroid hormone concentrations following chemical exposure in rodents was thought to be a reasonable initial screen. Concurrent histologic evaluation of the thyroid would strengthen this screen. Similar methods in teleosts may be useful as screens, but would require indicators of tissue production of thyroid hormones. The use of tadpole metamorphosis as a screen may also be useful; however, this method requires validation and standardization prior to use as a broad-based screen. PMID:10210697

  4. 21 CFR 862.1370 - Human growth hormone test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Human growth hormone test system. 862.1370 Section... Systems § 862.1370 Human growth hormone test system. (a) Identification. A human growth hormone test system is a device intended to measure the levels of human growth hormone in plasma. Human growth...

  5. 21 CFR 862.1485 - Luteinizing hormone test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Luteinizing hormone test system. 862.1485 Section... Systems § 862.1485 Luteinizing hormone test system. (a) Identification. A luteinizing hormone test system is a device intended to measure luteinizing hormone in serum and urine. Luteinizing...

  6. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  7. 21 CFR 862.1485 - Luteinizing hormone test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Luteinizing hormone test system. 862.1485 Section... Systems § 862.1485 Luteinizing hormone test system. (a) Identification. A luteinizing hormone test system is a device intended to measure luteinizing hormone in serum and urine. Luteinizing...

  8. 21 CFR 862.1545 - Parathyroid hormone test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Parathyroid hormone test system. 862.1545 Section... Systems § 862.1545 Parathyroid hormone test system. (a) Identification. A parathyroid hormone test system is a device intended to measure the levels of parathyroid hormone in serum and plasma....

  9. 21 CFR 862.1485 - Luteinizing hormone test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Luteinizing hormone test system. 862.1485 Section... Systems § 862.1485 Luteinizing hormone test system. (a) Identification. A luteinizing hormone test system is a device intended to measure luteinizing hormone in serum and urine. Luteinizing...

  10. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  11. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  12. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  13. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  14. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  15. 21 CFR 862.1545 - Parathyroid hormone test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Parathyroid hormone test system. 862.1545 Section... Systems § 862.1545 Parathyroid hormone test system. (a) Identification. A parathyroid hormone test system is a device intended to measure the levels of parathyroid hormone in serum and plasma....

  16. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  17. 21 CFR 862.1370 - Human growth hormone test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Human growth hormone test system. 862.1370 Section... Systems § 862.1370 Human growth hormone test system. (a) Identification. A human growth hormone test system is a device intended to measure the levels of human growth hormone in plasma. Human growth...

  18. 21 CFR 862.1370 - Human growth hormone test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Human growth hormone test system. 862.1370 Section... Systems § 862.1370 Human growth hormone test system. (a) Identification. A human growth hormone test system is a device intended to measure the levels of human growth hormone in plasma. Human growth...

  19. 21 CFR 862.1025 - Adrenocorticotropic hormone (ACTH) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Adrenocorticotropic hormone (ACTH) test system... Test Systems § 862.1025 Adrenocorticotropic hormone (ACTH) test system. (a) Identification. An adrenocorticotropic hormone (ACTH) test system is a device intended to measure adrenocorticotropic hormone in...

  20. 21 CFR 862.1545 - Parathyroid hormone test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Parathyroid hormone test system. 862.1545 Section... Systems § 862.1545 Parathyroid hormone test system. (a) Identification. A parathyroid hormone test system is a device intended to measure the levels of parathyroid hormone in serum and plasma....

  1. 21 CFR 862.1370 - Human growth hormone test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Human growth hormone test system. 862.1370 Section... Systems § 862.1370 Human growth hormone test system. (a) Identification. A human growth hormone test system is a device intended to measure the levels of human growth hormone in plasma. Human growth...

  2. 21 CFR 862.1485 - Luteinizing hormone test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Luteinizing hormone test system. 862.1485 Section... Systems § 862.1485 Luteinizing hormone test system. (a) Identification. A luteinizing hormone test system is a device intended to measure luteinizing hormone in serum and urine. Luteinizing...

  3. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  4. 21 CFR 862.1485 - Luteinizing hormone test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Luteinizing hormone test system. 862.1485 Section... Systems § 862.1485 Luteinizing hormone test system. (a) Identification. A luteinizing hormone test system is a device intended to measure luteinizing hormone in serum and urine. Luteinizing...

  5. 21 CFR 862.1545 - Parathyroid hormone test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Parathyroid hormone test system. 862.1545 Section... Systems § 862.1545 Parathyroid hormone test system. (a) Identification. A parathyroid hormone test system is a device intended to measure the levels of parathyroid hormone in serum and plasma....

  6. 21 CFR 862.1545 - Parathyroid hormone test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Parathyroid hormone test system. 862.1545 Section... Systems § 862.1545 Parathyroid hormone test system. (a) Identification. A parathyroid hormone test system is a device intended to measure the levels of parathyroid hormone in serum and plasma....

  7. 21 CFR 862.1370 - Human growth hormone test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Human growth hormone test system. 862.1370 Section... Systems § 862.1370 Human growth hormone test system. (a) Identification. A human growth hormone test system is a device intended to measure the levels of human growth hormone in plasma. Human growth...

  8. 21 CFR 862.1690 - Thyroid stimulating hormone test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Thyroid stimulating hormone test system. 862.1690... Systems § 862.1690 Thyroid stimulating hormone test system. (a) Identification. A thyroid stimulating hormone test system is a device intended to measure thyroid stimulating hormone, also known...

  9. Hormone-independent pathways of sexual differentiation.

    PubMed

    Renfree, Marilyn B; Chew, Keng Yih; Shaw, Geoffrey

    2014-01-01

    New observations over the last 25 years of hormone-independent sexual dimorphisms have gradually and unequivocally overturned the dogma, arising from Jost's elegant experiments in the mid-1900s, that all somatic sex dimorphisms in vertebrates arise from the action of gonadal hormones. Although we know that Sry, a Y-linked gene, is the primary gonadal sex determinant in mammals, more recent analysis in marsupials, mice, and finches has highlighted numerous sexual dimorphisms that are evident well before the differentiation of the testis and which cannot be explained by a sexually dimorphic hormonal environment. In marsupials, scrotal bulges and mammary primordia are visible before the testis has differentiated due to the expression of a gene(s) on the X chromosome. ZZ and ZW gynandromorph finches have brains that develop in a sexually dimorphic way dependent on their sex chromosome content. In genetically manipulated mice, it is the X chromosomes, not the gonads, that determine many characters including rate of early development, adiposity, and neural circuits. Even spotted hyenas have sexual dimorphisms that cannot be simply explained by hormonal exposure. This review discusses the recent findings that confirm that there are hormone-independent sexual dimorphisms well before the gonads begin to produce their hormones. PMID:24577198

  10. Human sexuality, sex hormones, and epilepsy.

    PubMed

    Morris, George L; Vanderkolk, Colleen

    2005-12-01

    The function of the hypothalamic-pituitary axis (HPA), including the production of luteinizing hormone, follicle-stimulating hormone, gonadotropin-releasing hormone, and prolactin, and the concentrations and metabolism of its end products, such as estrogen, testosterone, and dehydroepiandrosterone, appear to be modified in many people with epilepsy. Effects of the disorder itself and effects of antiepileptic drugs (AEDs) both appear to contribute to these hormonal alterations, which may be associated with sexual dysfunction. Focal epileptic discharges from the temporal lobe may affect HPA function, as is suggested by the normalization of androgen levels seen in men with temporal lobe epilepsy who become seizure-free after surgery. Hepatic enzyme-inducing AEDs such as carbamazepine and phenytoin may be most clearly linked to altered metabolism of sex steroid hormones, but valproic acid, an enzyme inhibitor, has also been implicated in the causation of reproductive endocrine abnormalities. Polycystic ovaries and polycystic ovarian syndrome (PCOS) are widely believed to be common in women with epilepsy, but the actual prevalence and the pathogenesis of PCOS in this population are disputed. Hormonal changes and sexual dysfunction need to be addressed in any comprehensive approach to epilepsy management, as well as any comprehensive epilepsy research program. Avoidance of enzyme-inducing AEDs and achievement of freedom from seizures as the goal of treatment are strongly recommended.

  11. An update: salivary hormones and physical exercise.

    PubMed

    Gatti, R; De Palo, E F

    2011-04-01

    Saliva contains cells and compounds, of local and non-local oral origin, namely inorganic, organic non-protein, protein/polypeptide, and lipid molecules. Moreover, some hormones, commonly assayed in plasma, such as steroids, are detectable in oral fluid and peptide/protein, and non-steroid hormones have been investigated. The sports practice environment and athletes' availability, together with hormone molecule characteristics in saliva and physical exercise behavior effects, confirm this body fluid as an alternative to serum. This review focuses on the relation between salivary steroids and psycho-physiological stress and underlines how the measurement of salivary cortisol provides an approach of self-report psychological indicator and anxiety change in relation to exercise performance. The correlation between salivary and plasma steroid hormone (cortisol, testosterone, and dehydroepiandrosterone (DHEA)) levels, observed during exercise, has been considered, underlining how the type, duration, and intensity of the exercise influence the salivary steroid concentrations in the same way as serum-level variations. Training conditions have been considered in relation to the salivary hormonal response. This review focuses on studies related to salivary hormone measurements, mainly steroids, in physical exercise. Saliva use in physical disciplines, as a real alternative to serum, could be a future perspective.

  12. Hormonal Perturbations in Occupationally Exposed Nickel Workers

    PubMed Central

    Beshir, Safia; Ibrahim, Khadiga Salah; Shaheen, Weam; Shahy, Eman M.

    2016-01-01

    BACKGROUND: Nickel exposure is recognized as an endocrine disruptor because of its adverse effects on reproduction. AIM: This study was designed to investigate the possible testiculo-hormonal perturbations on workers occupationally exposed to nickel and to assess its effects on human male sexual function. METHODS: Cross-sectional comparative study, comprising 105 electroplating male non-smoker, non-alcoholic workers exposed to soluble nickel and 60 controls was done. Serum luteinizing hormone, follicle stimulating hormone, testosterone levels and urinary nickel concentrations were determined for the studied groups. RESULTS: Serum luteinizing hormone, follicle stimulating hormone, urinary nickel and the simultaneous incidence of more than one sexual disorder were significantly higher in the exposed workers compared to controls. The occurrence of various types of sexual disorders (decreased libido, impotence and premature ejaculation) in the exposed workers was 9.5, 5.1 and 4.4 folds respectively than the controls. CONCLUSIONS: Exposure to nickel produces possible testiculo-hormonal perturbations in those exposed workers. PMID:27335607

  13. Isotretinoin, tetracycline and circulating hormones in acne.

    PubMed

    Palatsi, R; Ruokonen, A; Oikarinen, A

    1997-09-01

    Isotretinoin, used to treat severe acne, has been shown to induce hormonal changes, especially to reduce 5 alpha-reductase in the production of the tissue-derived dihydrotestosterone (DHT) metabolite 3 alpha-Adiol G. However, the effects of isotretinoin on other pituitary, adrenal or gonadal hormones have not been thoroughly elucidated. In the present study, isotretinoin administered at a dose of 0.5 mg/kg/day for 4 weeks caused no marked changes in the serum levels of pituitary, adrenal or gonadal hormones or 3 alpha-Adiol G in patients with severe papulopustulotic acne (n = 19). After 12 weeks of therapy, there was a decrease in the levels of the precursor androgens androstenedione, testosterone and 3 alpha-Adiol G in 6/9 patients. Acne improved after 4.5 months in all but 2 male patients, who had very low serum hormone binding globulins (SHBG) and a high free androgen index (FAI). Isotretinoin did not affect the elevated LH/FSH ratio in a patient with the polycystic ovarian syndrome (PCOS); nor did it change the high FAI or low SHBG in the male patients. For comparison, tetracycline had no effects on the serum hormonal levels of patients with mild acne (n = 19) after 7 days of treatment. This study confirms that the effects of isotretinoin on the serum hormone levels are small and unlikely to be of relevance for the resolution of acne or the suppression of sebum excretion. PMID:9298137

  14. Sex hormones and the dry eye.

    PubMed

    Truong, Susan; Cole, Nerida; Stapleton, Fiona; Golebiowski, Blanka

    2014-07-01

    The greater prevalence of dry eye in women compared to men suggests that sex hormones may have a role in this condition. This review aims to present evidence for how sex hormones may affect the ocular structures involved in the production, regulation and maintenance of the normal tear film. It is hypothesised that hormone changes alter the homeostasis of the ocular surface and contribute to dry eye. Androgens impact on the structure and function of the meibomian and lacrimal glands and therefore androgen deficiency is, at least in part, associated with the aetiology of dry eye. In contrast, reports of the effects of oestrogen and progesterone on these ocular structures and on the conjunctiva are contradictory and the mechanisms of action of these female-specific sex hormones in the eye are not well understood. The uncertainty of the effects of oestrogen and progesterone on dry eye symptoms is reflected in the controversial relationship between hormone replacement therapy and the signs and symptoms of dry eye. Current understanding of sex hormone influences on the immune system suggests that oestrogen may modulate a cascade of inflammatory events, which underlie dry eye.

  15. Rapid steroid hormone actions via membrane receptors.

    PubMed

    Schwartz, Nofrat; Verma, Anjali; Bivens, Caroline B; Schwartz, Zvi; Boyan, Barbara D

    2016-09-01

    Steroid hormones regulate a wide variety of physiological and developmental functions. Traditional steroid hormone signaling acts through nuclear and cytosolic receptors, altering gene transcription and subsequently regulating cellular activity. This is particularly important in hormonally-responsive cancers, where therapies that target classical steroid hormone receptors have become clinical staples in the treatment and management of disease. Much progress has been made in the last decade in detecting novel receptors and elucidating their mechanisms, particularly their rapid signaling effects and subsequent impact on tumorigenesis. Many of these receptors are membrane-bound and lack DNA-binding sites, functionally separating them from their classical cytosolic receptor counterparts. Membrane-bound receptors have been implicated in a number of pathways that disrupt the cell cycle and impact tumorigenesis. Among these are pathways that involve phospholipase D, phospholipase C, and phosphoinositide-3 kinase. The crosstalk between these pathways has been shown to affect apoptosis and proliferation in cardiac cells, osteoblasts, and chondrocytes as well as cancer cells. This review focuses on rapid signaling by 17β-estradiol and 1α,25-dihydroxy vitamin D3 to examine the integrated actions of classical and rapid steroid signaling pathways both in contrast to each other and in concert with other rapid signaling pathways. This new approach lends insight into rapid signaling by steroid hormones and its potential for use in targeted drug therapies that maximize the benefits of traditional steroid hormone-directed therapies while mitigating their less desirable effects. PMID:27288742

  16. Hypermetabolic Conversion of Plant Oil into Water: Endothermic Biochemical Process Stimulated by Juvenile Hormone in the European Firebug, Pyrrhocoris apterus L.

    PubMed Central

    Sláma, Karel; Lukáš, Jan

    2016-01-01

    the warm and cold larvae of P. apterus was only some 30% (not a reported 10-fold difference), which was presumably due to their ability to drink. We conclude that a very important, though still largely neglected, epigenetic biochemical role of insect JH depends on switchover between the utilization of dietary lipid (+JH; production of metabolic water) and carbohydrate (−JH; lipid storage in the fat body). The hypermetabolic water supply in insects fed on dry food, which is associated with enormous rates of O2 consumption, liberates endothermic energy that heats the body and potentially influences the insect thermoregulation. A possibility that the JH-dependent lipolytic hormone stimulates the total metabolic breakdown of nutritional lipids may be absolutely different from the currently known adipokinetic peptides that have been emphasized. PMID:27790049

  17. Obesity, growth hormone and exercise.

    PubMed

    Thomas, Gwendolyn A; Kraemer, William J; Comstock, Brett A; Dunn-Lewis, Courtenay; Maresh, Carl M; Volek, Jeff S

    2013-09-01

    Growth hormone (GH) is regulated, suppressed and stimulated by numerous physiological stimuli. However, it is believed that obesity disrupts the physiological and pathological factors that regulate, suppress or stimulate GH release. Pulsatile GH has been potently stimulated in healthy subjects by both aerobic and resistance exercise of the right intensity and duration. GH modulates fuel metabolism, reduces total fat mass and abdominal fat mass, and could be a potent stimulus of lipolysis when administered to obese individuals exogenously. Only pulsatile GH has been shown to augment adipose tissue lipolysis and, therefore, increasing pulsatile GH response may be a therapeutic target. This review discusses the factors that cause secretion of GH, how obesity may alter GH secretion and how both aerobic and resistance exercise stimulates GH, as well as how exercise of a specific intensity may be used as a stimulus for GH release in individuals who are obese. Only five prior studies have investigated exercise as a stimulus of endogenous GH in individuals who are obese. Based on prior literature, resistance exercise may provide a therapeutic target for releasing endogenous GH in individuals who are obese if specific exercise programme variables are utilized. Biological activity of GH indicates that this may be an important precursor to beneficial changes in body fat and lean tissue mass in obese individuals. However, additional research is needed including what molecular GH variants are acutely released and involved at target tissues as a result of different exercise stimuli and what specific exercise programme variables may serve to stimulate GH in individuals who are obese.

  18. Hormone-dependent aggression in male and female rats: experiential, hormonal, and neural foundations.

    PubMed

    Albert, D J; Jonik, R H; Walsh, M L

    1992-01-01

    Hormone-dependent aggression in both male and female rats includes the distinctive behavioral characteristics of piloerection and lateral attack. In males the aggression is dependent on testicular testosterone and is commonly known as intermale aggression. In females, the aggression is most commonly observed as maternal aggression and is dependent on hormones whose identity is only beginning to emerge. The present review examines the experiential events which activate hormone-dependent aggression, the relation of the aggression to gonadal hormones, and the neural structures that participate in its modulation. In males and females, the aggression is activated by cohabitation with a conspecific of the opposite sex, by competitive experience, and by repeated exposure to unfamiliar conspecifics. In the female, the presence of pups also activates aggression. In both males and females, hormones are necessary for the full manifestation of the aggression. The essential hormone appears to be testosterone in males and a combination of testosterone and estradiol in females. The information available suggests the neural control systems for hormone-dependent aggression may be similar in males and females. It is argued that hormone-dependent aggression is behaviorally and biologically homologous in male and female rats.

  19. Control of Pituitary Thyroid-stimulating Hormone Synthesis and Secretion by Thyroid Hormones during Xenopus Metamorphosis

    EPA Science Inventory

    Serum thyroid hormone (TH) concentrations in anuran larvae rise rapidly during metamorphosis. Such a rise in an adult anuran would inevitably trigger a negative feedback response resulting in decreased synthesis and secretion of thyroid-stimulating hormone (TSH) by the pituitary....

  20. Growth Hormone Research Society perspective on the development of long-acting growth hormone preparations

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Growth Hormone (GH) Research Society (GRS) convened a workshop to address important issues regarding trial design, efficacy, and safety of long-acting growth hormone preparations (LAGH). A closed meeting of 55 international scientists with expertise in GH, including pediatric and adult endocrino...

  1. Negative regulation of parathyroid hormone-related protein expression by steroid hormones.

    PubMed

    Kajitani, Takashi; Tamamori-Adachi, Mimi; Okinaga, Hiroko; Chikamori, Minoru; Iizuka, Masayoshi; Okazaki, Tomoki

    2011-04-15

    Elevated parathyroid hormone-related protein (PTHrP) is responsible for humoral hypercalcemia of malignancy (HHM), which is of clinical significance in treatment of terminal patients with malignancies. Steroid hormones were known to cause suppression of PTHrP expression. However, detailed studies linking multiple steroid hormones to PTHrP expression are lacking. Here we studied PTHrP expression in response to steroid hormones in four cell lines with excessive PTHrP production. Our study established that steroid hormones negatively regulate PTHrP expression. Vitamin D receptor, estrogen receptor α, glucocorticoid receptor, and progesterone receptor, were required for repression of PTHrP expression by the cognate ligands. A notable exception was the androgen receptor, which was dispensable for suppression of PTHrP expression in androgen-treated cells. We propose a pathway(s) involving nuclear receptors to suppress PTHrP expression.

  2. Actions of Thyroid Hormone Analogues on Chemokines.

    PubMed

    Davis, Paul J; Glinsky, Gennadi V; Lin, Hung-Yun; Mousa, Shaker A

    2016-01-01

    The extracellular domain of plasma membrane integrin αvβ3 contains a receptor for thyroid hormone (L-thyroxine, T4; 3,5,3'-triiodo-L-thyronine, T3); this receptor also binds tetraiodothyroacetic acid (tetrac), a derivative of T4. Tetrac inhibits the binding of T4 and T3 to the integrin. Fractalkine (CX3CL1) is a chemokine relevant to inflammatory processes in the CNS that are microglia-dependent but also important to normal brain development. Expression of the CX3CL1 gene is downregulated by tetrac, suggesting that T4 and T3 may stimulate fractalkine expression. Independently of its specific receptor (CX3CR1), fractalkine binds to αvβ3 at a site proximal to the thyroid hormone-tetrac receptor and changes the physical state of the integrin. Tetrac also affects expression of the genes for other CNS-relevant chemokines, including CCL20, CCL26, CXCL2, CXCL3, and CXCL10. The chemokine products of these genes are important to vascularity of the brain, particularly of the choroid plexus, to inflammatory processes in the CNS and, in certain cases, to neuroprotection. Thyroid hormones are known to contribute to regulation of each of these CNS functions. We propose that actions of thyroid hormone and hormone analogues on chemokine gene expression contribute to regulation of inflammatory processes in brain and of brain blood vessel formation and maintenance. PMID:27493972

  3. How to use and interpret hormone ratios.

    PubMed

    Sollberger, Silja; Ehlert, Ulrike

    2016-01-01

    Hormone ratios have become increasingly popular throughout the neuroendocrine literature since they offer a straightforward way to simultaneously analyze the effects of two interdependent hormones. However, the analysis of ratios is associated with statistical and interpretational concerns which have not been sufficiently considered in the context of endocrine research. The aim of this article, therefore, is to demonstrate and discuss these issues, and to suggest suitable ways to address them. In a first step, we use exemplary testosterone and cortisol data to illustrate that one major concern of ratios lies in their distribution and inherent asymmetry. As a consequence, results of parametric statistical analyses are affected by the ultimately arbitrary decision of which way around the ratio is computed (i.e., A/B or B/A). We suggest the use of non-parametric methods as well as the log-transformation of hormone ratios as appropriate methods to deal with these statistical problems. However, in a second step, we also discuss the complicated interpretation of ratios, and propose moderation analysis as an alternative and oftentimes more insightful approach to ratio analysis. In conclusion, we suggest that researchers carefully consider which statistical approach is best suited to investigate reciprocal hormone effects. With regard to the hormone ratio method, further research is needed to specify what exactly this index reflects on the biological level and in which cases it is a meaningful variable to analyze.

  4. Sex hormones and brain dopamine functions.

    PubMed

    Sotomayor-Zarate, Ramon; Cruz, Gonzalo; Renard, Georgina M; Espinosa, Pedro; Ramirez, Victor D

    2014-01-01

    Sex hormones exert differential effects on a variety of sensitive tissues like the reproductive tract, gonads, liver, bone and adipose tissue, among others. In the brain, sex hormones act as neuroactive steroids regulating the function of neuroendocrine diencephalic structures like the hypothalamus. In addition, steroids can exert physiological effects upon cortical, limbic and midbrain structures, influencing different behaviors such as memory, learning, mood and reward. In the last three decades, the role of sex hormones on monoamine neurotransmitters in extra-hypothalamic areas related to motivated behaviors, learning and locomotion has been the focus of much research. The purpose of this thematic issue is to present the state of art concerning the effects of sex hormones on the neurochemical regulation of dopaminergic midbrain areas involved in neurobiological and pathological processes, such as addiction to drugs of abuse. We also discuss evidence of how neonatal exposure to sex hormones or endocrine disrupting chemicals can produce long-term changes on the neurochemical regulation of dopaminergic neurons in the limbic and midbrain areas. PMID:25540983

  5. Metabolic hormones in saliva: origins and functions

    PubMed Central

    Zolotukhin, S.

    2012-01-01

    The salivary proteome consists of thousands of proteins, which include, among others, hormonal modulators of energy intake and output. Although the functions of this prominent category of hormones in whole body energy metabolism are well characterized, their functions in the oral cavity, whether as a salivary component, or when expressed in taste cells, are less studied and poorly understood. The respective receptors for the majority of salivary metabolic hormones have been also shown to be expressed in salivary glands, taste cells, or other cells in the oral mucosa. This review provides a comprehensive account of the gastrointestinal hormones, adipokines, and neuropeptides identified in saliva, salivary glands, or lingual epithelium, as well as their respective cognate receptors expressed in the oral cavity. Surprisingly, few functions are assigned to salivary metabolic hormones, and these functions are mostly associated with the modulation of taste perception. Because of the well-characterized correlation between impaired oral nutrient sensing and increased energy intake and body mass index, a conceptually provocative point of view is introduced, whereupon it is argued that targeted changes in the composition of saliva could affect whole body metabolism in response to the activation of cognate receptors expressed locally in the oral mucosa. PMID:22994880

  6. Actions of Thyroid Hormone Analogues on Chemokines

    PubMed Central

    Glinsky, Gennadi V.

    2016-01-01

    The extracellular domain of plasma membrane integrin αvβ3 contains a receptor for thyroid hormone (L-thyroxine, T4; 3,5,3′-triiodo-L-thyronine, T3); this receptor also binds tetraiodothyroacetic acid (tetrac), a derivative of T4. Tetrac inhibits the binding of T4 and T3 to the integrin. Fractalkine (CX3CL1) is a chemokine relevant to inflammatory processes in the CNS that are microglia-dependent but also important to normal brain development. Expression of the CX3CL1 gene is downregulated by tetrac, suggesting that T4 and T3 may stimulate fractalkine expression. Independently of its specific receptor (CX3CR1), fractalkine binds to αvβ3 at a site proximal to the thyroid hormone-tetrac receptor and changes the physical state of the integrin. Tetrac also affects expression of the genes for other CNS-relevant chemokines, including CCL20, CCL26, CXCL2, CXCL3, and CXCL10. The chemokine products of these genes are important to vascularity of the brain, particularly of the choroid plexus, to inflammatory processes in the CNS and, in certain cases, to neuroprotection. Thyroid hormones are known to contribute to regulation of each of these CNS functions. We propose that actions of thyroid hormone and hormone analogues on chemokine gene expression contribute to regulation of inflammatory processes in brain and of brain blood vessel formation and maintenance. PMID:27493972

  7. The common molecular players in plant hormone crosstalk and signaling.

    PubMed

    Ohri, Puja; Bhardwaj, Renu; Bali, Shagun; Kaur, Ravinderjit; Jasrotia, Shivam; Khajuria, Anjali; Parihar, Ripu D

    2015-01-01

    Plant growth and development is under the control of mutual interactions among plant hormones. The five classical categories of plant hormones include auxins, cytokinins, gibberellins, abscisic acid and ethylene. Additionally, newer classes of plant hormones have been recognized like brassinosteroids, jasmonic acid, salicylic acid and polyamines. These hormones play significant roles in regulating the plant growth and development. Various receptors and key signaling components of these hormones have been studied and identified. At genetic level, crosstalk among the various plant hormones is found to be antagonistic or synergistic. In addition, components of signaling pathway of one plant hormone interact with the signaling components of other hormone. Thus, an attempt has been made to review the literature regarding the role of plant hormones in plant physiology and the common molecular players in their signaling and crosstalk.

  8. Thyroid hormone signaling in energy homeostasis and energy metabolism

    PubMed Central

    McAninch, Elizabeth A.; Bianco, Antonio C.

    2014-01-01

    The thyroid hormone plays a significant role in diverse processes related to growth, development, differentiation, and metabolism. Thyroid hormone signaling modulates energy expenditure through both central and peripheral pathways. At the cellular level, the thyroid hormone exerts its effects after concerted mechanisms facilitate binding to the thyroid hormone receptor. In the hypothalamus, signals from a range of metabolic pathways, including appetite, temperature, afferent stimuli via the autonomic nervous system, availability of energy substrates, hormones, and other biologically active molecules, converge to maintain plasma thyroid hormone at the appropriate level to preserve energy homeostasis. At the tissue level, thyroid hormone actions on metabolism are controlled by transmembrane transporters, deiodinases, and thyroid hormone receptors. In the modern environment, humans are susceptible to an energy surplus, which has resulted in an obesity epidemic and thus understanding the contribution of the thyroid hormone to cellular and organism metabolism is increasingly relevant. PMID:24697152

  9. The "multiple hormone deficiency" theory of aging: is human senescence caused mainly by multiple hormone deficiencies?

    PubMed

    Hertoghe, T

    2005-12-01

    In the human body, the productions, levels and cell receptors of most hormones progressively decline with age, gradually putting the body into various states of endocrine deficiency. The circadian cycles of these hormones also change, sometimes profoundly, with time. In aging individuals, the well-balanced endocrine system can fall into a chaotic condition with losses, phase-advancements, phase delays, unpredictable irregularities of nycthemeral hormone cycles, in particular in very old or sick individuals. The desynchronization makes hormone activities peak at the wrong times and become inefficient, and in certain cases health threatening. The occurrence of multiple hormone deficits and spilling through desynchronization may constitute the major causes of human senescence, and they are treatable causes. Several arguments can be put forward to support the view that senescence is mainly a multiple hormone deficiency syndrome: First, many if not most of the signs, symptoms and diseases (including cardiovascular diseases, cancer, obesity, diabetes, osteoporosis, dementia) of senescence are similar to physical consequences of hormone deficiencies and may be caused by hormone deficiencies. Second, most of the presumed causes of senescence such as excessive free radical formation, glycation, cross-linking of proteins, imbalanced apoptosis system, accumulation of waste products, failure of repair systems, deficient immune system, may be caused or favored by hormone deficiencies. Even genetic causes such as limits to cell proliferation (such as the Hayflick limit of cell division), poor gene polymorphisms, premature telomere shortening and activation of possible genetic "dead programs" may have links with hormone deficiencies, being either the consequence, the cause, or the major favoring factor of hormone deficiencies. Third, well-dosed and -balanced hormone supplements may slow down or stop the progression of signs, symptoms, or diseases of senescence and may often

  10. Steroid hormone sulphation in lead workers.

    PubMed Central

    Apostoli, P; Romeo, L; Peroni, E; Ferioli, A; Ferrari, S; Pasini, F; Aprili, F

    1989-01-01

    The metabolism of steroid hormones has been investigated in 10 workers exposed to lead and in 10 non-exposed subjects to determine whether lead interferes with the first or second phase reactions of steroid hormone biotransformation, or both. In the exposed workers blood lead concentrations (PbB) ranged from 45 to 69 micrograms/100 ml; in the controls PbB was less than 25 micrograms/100 ml. No statistical differences were found for the total amount of the urinary hormone metabolites, but a drop of about 50% was observed for the sulphated portion. It is suggested that lead interferes with the mechanisms of sulphoconjugation through an effect on the cytosol enzymes sulphotransferase and sulphokinase. PMID:2930732

  11. Gravitational effects on plant growth hormone concentration

    NASA Technical Reports Server (NTRS)

    Bandurski, R. S.; Schulze, A.

    1983-01-01

    Dolk's (1936) finding that more growth hormone diffuses from the lower side of a gravity-stimulated plant shoot than from the upper side is presently confirmed by means of both an isotope dilution assay and selected ion monitoring-gas chromatography-mass spectrometry, and it is established that the asymmetrically distributed hormone is indole-3-acetic acid (IAA). This is the first physicochemical demonstration that there is more IAA on the lower sides of a geostimulated plant shoot. It is also found that free IAA primarily occurs in the conductive vascular tissues of the shoot, while IAA esters predominate in the growing cortical cells. A highly sensitive gas chromatographic isotope dilution assay shows that the hormone asymmetry also occurs in the nonvascular tissue.

  12. Thyroid hormone metabolism and environmental chemical exposure

    PubMed Central

    2012-01-01

    Background Polychlorinated dioxins and –furans (PCDD/Fs) and polychlorinated-biphenyls (PCBs) are environmental toxicants that have been proven to influence thyroid metabolism both in animal studies and in human beings. In recent years polybrominated diphenyl ethers (PBDEs) also have been found to have a negative influence on thyroid hormone metabolism. The lower brominated flame retardants are now banned in the EU, however higher brominated decabromo-diphenyl ether (DBDE) and the brominated flame retardant hexabromocyclododecane (HBCD) are not yet banned. They too can negatively influence thyroid hormone metabolism. An additional brominated flame retardant that is still in use is tetrabromobisphenol-A (TBBPA), which has also been shown to influence thyroid hormone metabolism. Influences of brominated flame retardants, PCDD/F’s and dioxin like-PCBs (dl-PCB’s) on thyroid hormone metabolism in adolescence in the Netherlands will be presented in this study and determined if there are reasons for concern to human health for these toxins. In the period 1987-1991, a cohort of mother-baby pairs was formed in order to detect abnormalities in relation to dioxin levels in the perinatal period. The study demonstrated that PCDD/Fs were found around the time of birth, suggesting a modulation of the setpoint of thyroid hormone metabolism with a higher 3,3’, 5,5’tetrathyroxine (T4) levels and an increased thyroid stimulating hormone (TSH). While the same serum thyroid hormone tests (- TSH and T4) were again normal by 2 years of age and were still normal at 8-12 years, adolescence is a period with extra stress on thyroid hormone metabolism. Therefore we measured serum levels of TSH, T4, 3,3’,5- triiodothyronine (T3), free T4 (FT4), antibodies and thyroxine-binding globulin (TBG) in our adolescent cohort. Methods Vena puncture was performed to obtain samples for the measurement of thyroid hormone metabolism related parameters and the current serum dioxin (PCDD/Fs), PCB

  13. Plant hormones: a fungal point of view.

    PubMed

    Chanclud, Emilie; Morel, Jean-Benoit

    2016-10-01

    Most classical plant hormones are also produced by pathogenic and symbiotic fungi. The way in which these molecules favour the invasion of plant tissues and the development of fungi inside plant tissues is still largely unknown. In this review, we examine the different roles of such hormone production by pathogenic fungi. Converging evidence suggests that these fungal-derived molecules have potentially two modes of action: (i) they may perturb plant processes, either positively or negatively, to favour invasion and nutrient uptake; and (ii) they may also act as signals for the fungi themselves to engage appropriate developmental and physiological processes adapted to their environment. Indirect evidence suggests that abscisic acid, gibberellic acid and ethylene produced by fungi participate in pathogenicity. There is now evidence that auxin and cytokinins could be positive regulators required for virulence. Further research should establish whether or not fungal-derived hormones act like other fungal effectors.

  14. Plant hormone interactions: how complex are they?

    PubMed

    Ross, John J; Weston, Diana E; Davidson, Sandra E; Reid, James B

    2011-04-01

    Models describing plant hormone interactions are often complex and web-like. Here we assess several suggested interactions within one experimental system, elongating pea internodes. Results from this system indicate that at least some suggested interactions between auxin, gibberellins (GAs), brassinosteroids (BRs), abscisic acid (ABA) and ethylene do not occur in this system or occur in the reverse direction to that suggested. Furthermore, some of the interactions are relatively weak and may be of little physiological relevance. This is especially true if plant hormones are assumed to show a log-linear response curve as many empirical results suggest. Although there is strong evidence to support some interactions between hormones (e.g. auxin stimulating ethylene and bioactive GA levels), at least some of the web-like complexities do not appear to be justified or are overstated. Simpler and more targeted models may be developed by dissecting out key interactions with major physiological effects. PMID:21214880

  15. Thyroid Hormones, Oxidative Stress, and Inflammation.

    PubMed

    Mancini, Antonio; Di Segni, Chantal; Raimondo, Sebastiano; Olivieri, Giulio; Silvestrini, Andrea; Meucci, Elisabetta; Currò, Diego

    2016-01-01

    Inflammation and oxidative stress (OS) are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS) that typically manifests as reduced conversion of thyroxine (T4) to triiodothyronine (T3) in different acute and chronic systemic conditions is still a debated topic. The pathophysiological mechanisms of this syndrome are reviewed, together with the roles of deiodinases, the enzymes responsible for the conversion of T4 to T3, in both physiological and pathological situations. The presence of OS indexes in NTIS supports the hypothesis that it represents a condition of hypothyroidism at the tissue level and not only an adaptive mechanism to diseases. PMID:27051079

  16. Thyroid Hormones, Oxidative Stress, and Inflammation.

    PubMed

    Mancini, Antonio; Di Segni, Chantal; Raimondo, Sebastiano; Olivieri, Giulio; Silvestrini, Andrea; Meucci, Elisabetta; Currò, Diego

    2016-01-01

    Inflammation and oxidative stress (OS) are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS) that typically manifests as reduced conversion of thyroxine (T4) to triiodothyronine (T3) in different acute and chronic systemic conditions is still a debated topic. The pathophysiological mechanisms of this syndrome are reviewed, together with the roles of deiodinases, the enzymes responsible for the conversion of T4 to T3, in both physiological and pathological situations. The presence of OS indexes in NTIS supports the hypothesis that it represents a condition of hypothyroidism at the tissue level and not only an adaptive mechanism to diseases.

  17. Thyroid Hormones, Oxidative Stress, and Inflammation

    PubMed Central

    Raimondo, Sebastiano; Olivieri, Giulio; Meucci, Elisabetta; Currò, Diego

    2016-01-01

    Inflammation and oxidative stress (OS) are closely related processes, as well exemplified in obesity and cardiovascular diseases. OS is also related to hormonal derangement in a reciprocal way. Among the various hormonal influences that operate on the antioxidant balance, thyroid hormones play particularly important roles, since both hyperthyroidism and hypothyroidism have been shown to be associated with OS in animals and humans. In this context, the nonthyroidal illness syndrome (NTIS) that typically manifests as reduced conversion of thyroxine (T4) to triiodothyronine (T3) in different acute and chronic systemic conditions is still a debated topic. The pathophysiological mechanisms of this syndrome are reviewed, together with the roles of deiodinases, the enzymes responsible for the conversion of T4 to T3, in both physiological and pathological situations. The presence of OS indexes in NTIS supports the hypothesis that it represents a condition of hypothyroidism at the tissue level and not only an adaptive mechanism to diseases. PMID:27051079

  18. Influence of Thyroid Hormones on Tendon Homeostasis.

    PubMed

    Oliva, Francesco; Piccirilli, Eleonora; Berardi, Anna C; Tarantino, Umberto; Maffulli, Nicola

    2016-01-01

    Tendinopathies have a multifactorial etiology driven by extrinsic and intrinsic factors. Recent studies have elucidated the importance of thyroid hormones in the alteration of tendons homeostasis and in the failure of tendon healing after injury. The effects of thyroid hormones are mediated by receptors (TR)-α and -β that seem to be ubiquitous. In particular, T3 and T4 play an antiapoptotic role on tenocytes, causing an increase in vital tenocytes isolated from tendons in vitro and a reduction of apoptotic ones; they are also able to influence extra cellular matrix proteins secretion in vitro from tenocytes, enhancing collagen production. From a clinical point of view, disorders of thyroid function have been investigated only for rotator cuff calcific tendinopathy and tears. In this complex scenario, further research is needed to clarify the role of thyroid hormones on the onset of tendinopathies. PMID:27535255

  19. Preventing leaf identity theft with hormones.

    PubMed

    Lumba, Shelley; McCourt, Peter

    2005-10-01

    Genetic analysis of plant development has begun to demonstrate the importance of hormone synthesis and transport in regulating morphogenesis. In the case of leaf development, for example, auxin pooling determines where a primordium will emerge and leads to the activation of transcription factors, which determine leaf identities by modulating abscisic acid (ABA) and gibberellic acid (GA) concentrations. Signal transduction studies suggest that negative regulation of transcription factors through protein turnover is commonly used as a mechanism of hormone action. Together, these findings suggest that auxin might degrade a repressor that allows the activation of genes that modulate ABA/GA ratios in emerging leaves. With our increased understanding of the molecular basis of hormone signaling, it is becoming possible to overlay important regulators onto signaling modules that determine morphological outputs.

  20. Control of growth hormone synthesis.

    PubMed

    Tuggle, C K; Trenkle, A

    1996-01-01

    A large body of research, primarily in the rodent and human species, has elucidated many of the details regarding the control of GH synthesis and release. Cell type-specific transcriptional control has been identified as the main mechanism of the somatotroph-specific expression of GH. The recent detailed analysis in rodents and humans of a highly specific transcriptional activator protein, PIT-1, has opened several new areas of study. This is especially true for research in the farm animal species, where PIT-1 has been cloned and its binding elements on the GH gene are being investigated in a number of economically important species. Genetic and biochemical analyses of PIT-1 and other GH regulators have shown the central role of PIT-1 not only in the cell-autonomous stimulation of GH gene transcription, but also in the participation of PIT-1 in the response at the GH gene to exogenous hormones such as RA and TH. PIT-1 has been implicated in the proliferative development of the pituitary itself, in the maintenance of anterior pituitary cell types once cell types are defined, and in the mechanism by which the hypothalamic signal for GH release is transduced. However, PIT-1 by itself does not activate the GH gene, so that additional unknown factors exist that need to be identified to fully understand the cell type-specific activation of the GH gene. In addition, GH gene regulatory elements acting through well-characterized systems such as TH have seemingly different effects; the specific context of the regulatory elements relative to the promoter elements appear to be crucial. These contextual details of GH gene regulation are not well understood for any species and need to be further studied to be able to make predictions for particular elements and regulatory mechanisms across species. The regulation of the pulsatile secretion of GH by GHRH and SRIH is reasonably well understood after the cloning and analysis of the two releasing factors and their receptors

  1. Contraceptive Hormone Use and Cardiovascular Disease

    PubMed Central

    Shufelt, Chrisandra L.; Noel Bairey Merz, C.

    2009-01-01

    Contraceptive hormones, most commonly prescribed as oral contraceptives (OC), are a widely utilized method to prevent ovulation, implantation and therefore pregnancy. The Women’s Health Initiative demonstrated cardiovascular risk linked to menopausal hormone therapy among women without pre-existing cardiovascular disease, prompting review of the safety, efficacy and side effects of other forms of hormone therapy. A variety of basic science, animal and human data suggest that contraceptive hormones have anti-atheromatous effects, however relatively less is known regarding the impact on atherosclerosis, thrombosis, vasomotion and arrhythmogenesis. Newer generation OC formulations currently in use indicate no increased myocardial infarction (MI) risk for current users, but a persistent increased risk of venous thrombo-embolism (VTE). There are no cardiovascular data available for the newest generation contraceptive hormone formulations, including those that contain newer progestins that lower blood pressure, as well as the non-oral routes (topical and vaginal). Current guidelines indicate that, as with all medication, contraceptive hormones should be selected and initiated by weighing risks and benefits for the individual patient. Women 35 years and older should be assessed for cardiovascular risk factors including hypertension, smoking, diabetes, nephropathy and other vascular diseases including migraines, prior to use. Existing data are mixed with regard to possible protection from OC for atherosclerosis and cardiovascular events; longer-term cardiovascular follow-up of menopausal women with regard to prior OC use, including subgroup information regarding adequacy of ovulatory cycling, the presence of hyperandrogenic conditions, and the presence of prothrombotic genetic disorders is needed to address this important issue. PMID:19147038

  2. How sex hormones promote skeletal muscle regeneration.

    PubMed

    Velders, Martina; Diel, Patrick

    2013-11-01

    Skeletal muscle regeneration efficiency declines with age for both men and women. This decline impacts on functional capabilities in the elderly and limits their ability to engage in regular physical activity and to maintain independence. Aging is associated with a decline in sex hormone production. Therefore, elucidating the effects of sex hormone substitution on skeletal muscle homeostasis and regeneration after injury or disuse is highly relevant for the aging population, where sarcopenia affects more than 30 % of individuals over 60 years of age. While the anabolic effects of androgens are well known, the effects of estrogens on skeletal muscle anabolism have only been uncovered in recent times. Hence, the purpose of this review is to provide a mechanistic insight into the regulation of skeletal muscle regenerative processes by both androgens and estrogens. Animal studies using estrogen receptor (ER) antagonists and receptor subtype selective agonists have revealed that estrogens act through both genomic and non-genomic pathways to reduce leukocyte invasion and increase satellite cell numbers in regenerating skeletal muscle tissue. Although animal studies have been more conclusive than human studies in establishing a role for sex hormones in the attenuation of muscle damage, data from a number of recent well controlled human studies is presented to support the notion that hormonal therapies and exercise induce added positive effects on functional measures and lean tissue mass. Based on the fact that aging human skeletal muscle retains the ability to adapt to exercise with enhanced satellite cell activation, combining sex hormone therapies with exercise may induce additive effects on satellite cell accretion. There is evidence to suggest that there is a 'window of opportunity' after the onset of a hypogonadal state such as menopause, to initiate a hormonal therapy in order to achieve maximal benefits for skeletal muscle health. Novel receptor subtype selective

  3. Oral manifestations in growth hormone disorders.

    PubMed

    Atreja, Gaurav; Atreja, Shikha Handa; Jain, Nitul; Sukhija, Urvashi

    2012-05-01

    Growth hormone is of vital importance for normal growth and development. Individuals with growth hormone deficiency develop pituitary dwarfism with disproportionate delayed growth of skull and facial skeleton giving them a small facial appearance for their age. Both hyper and hypopituitarism have a marked effect on development of oro-facial structures including eruption and shedding patterns of teeth, thus giving an opportunity to treating dental professionals to first see the signs and symptoms of these growth disorders and correctly diagnose the serious underlying disease. PMID:22629503

  4. A major thyroid hormone response element in the third intron of the rat growth hormone gene.

    PubMed Central

    Sap, J; de Magistris, L; Stunnenberg, H; Vennström, B

    1990-01-01

    The rat growth hormone (RGH) gene constitutes a well-documented model system for the direct regulation of transcription by thyroid hormones. In order to analyse its interaction with sequences in the RGH gene, we have overproduced the thyroid hormone receptor-alpha (c-erbA) protein using a vaccinia virus expression system. The expressed protein bound T3 and DNA-cellulose with expected affinities, and the major binding site for the receptor protein was found to be located in the third intron of the RGH gene. This site displayed significantly higher affinity for the receptor protein than a previously described thyroid hormone response element (TRE) in the promoter of this gene, and also conferred stronger hormone responsiveness in vivo to a heterologous promoter. The data suggest that this novel TRE plays a major role in the regulation of rat growth hormone gene expression by thyroid hormones. Images Fig. 1. Fig. 3. Fig. 4. Fig. 5. Fig. 6. Fig. 7. Fig. 8. PMID:2155782

  5. Sex, hormones and neurogenesis in the hippocampus: hormonal modulation of neurogenesis and potential functional implications.

    PubMed

    Galea, L A M; Wainwright, S R; Roes, M M; Duarte-Guterman, P; Chow, C; Hamson, D K

    2013-11-01

    The hippocampus is an area of the brain that undergoes dramatic plasticity in response to experience and hormone exposure. The hippocampus retains the ability to produce new neurones in most mammalian species and is a structure that is targeted in a number of neurodegenerative and neuropsychiatric diseases, many of which are influenced by both sex and sex hormone exposure. Intriguingly, gonadal and adrenal hormones affect the structure and function of the hippocampus differently in males and females. Adult neurogenesis in the hippocampus is regulated by both gonadal and adrenal hormones in a sex- and experience-dependent way. Sex differences in the effects of steroid hormones to modulate hippocampal plasticity should not be completely unexpected because the physiology of males and females is different, with the most notable difference being that females gestate and nurse the offspring. Furthermore, reproductive experience (i.e. pregnancy and mothering) results in permanent changes to the maternal brain, including the hippocampus. This review outlines the ability of gonadal and stress hormones to modulate multiple aspects of neurogenesis (cell proliferation and cell survival) in both male and female rodents. The function of adult neurogenesis in the hippocampus is linked to spatial memory and depression, and the present review provides early evidence of the functional links between the hormonal modulation of neurogenesis that may contribute to the regulation of cognition and stress.

  6. Negative regulation of parathyroid hormone-related protein expression by steroid hormones

    SciTech Connect

    Kajitani, Takashi; Tamamori-Adachi, Mimi; Okinaga, Hiroko; Chikamori, Minoru; Iizuka, Masayoshi; Okazaki, Tomoki

    2011-04-15

    Highlights: {yields} Steroid hormones repress expression of PTHrP in the cell lines where the corresponding nuclear receptors are expressed. {yields} Nuclear receptors are required for suppression of PTHrP expression by steroid hormones, except for androgen receptor. {yields} Androgen-induced suppression of PTHrP expression appears to be mediated by estrogen receptor. -- Abstract: Elevated parathyroid hormone-related protein (PTHrP) is responsible for humoral hypercalcemia of malignancy (HHM), which is of clinical significance in treatment of terminal patients with malignancies. Steroid hormones were known to cause suppression of PTHrP expression. However, detailed studies linking multiple steroid hormones to PTHrP expression are lacking. Here we studied PTHrP expression in response to steroid hormones in four cell lines with excessive PTHrP production. Our study established that steroid hormones negatively regulate PTHrP expression. Vitamin D receptor, estrogen receptor {alpha}, glucocorticoid receptor, and progesterone receptor, were required for repression of PTHrP expression by the cognate ligands. A notable exception was the androgen receptor, which was dispensable for suppression of PTHrP expression in androgen-treated cells. We propose a pathway(s) involving nuclear receptors to suppress PTHrP expression.

  7. Retrospective evaluation of sex hormones and steroid hormone intermediates in dogs with alopecia.

    PubMed

    Frank, Linda A; Hnilica, Keith A; Rohrbach, Barton W; Oliver, Jack W

    2003-04-01

    The purpose of this study was to determine if there are specific steroid hormone aberrations associated with suspect endocrine alopecias in dogs in whom hypothyroidism and hyperadrenocorticism have been excluded. Steroid hormone panels submitted to the UTCVM endocrinology laboratory over a 7.5-year period (783 samples) from dogs with alopecia were reviewed. During this period, 276 dogs met the criteria for inclusion and were comprised of 54 different breeds. Approximately 73% of dogs had at least one baseline or post-ACTH stimulation steroid hormone intermediate greater than the normal range. The most frequent hormone elevation noted was for progesterone (57.6% of samples). When compared with normal dogs, oestradiol was significantly greater in Keeshond dogs and progesterone was significantly greater in Pomeranian and Siberian Husky dogs. Not all individual dogs had hormone abnormalities. Chow Chow, Samoyed and Malamute dogs had the greatest percentage of normal steroid hormone intermediates of the dogs in this study. Baseline cortisol concentrations were significantly correlated with progesterone, 17-hydroxyprogesterone (17-OHP) and androstenedione. Results of this study suggest that the pathomechanism of the alopecia, at least for some breeds, may not relate to steroid hormone intermediates and emphasizes the need for breed specific normals.

  8. Plant hormone signaling during development: insights from computational models.

    PubMed

    Oliva, Marina; Farcot, Etienne; Vernoux, Teva

    2013-02-01

    Recent years have seen an impressive increase in our knowledge of the topology of plant hormone signaling networks. The complexity of these topologies has motivated the development of models for several hormones to aid understanding of how signaling networks process hormonal inputs. Such work has generated essential insights into the mechanisms of hormone perception and of regulation of cellular responses such as transcription in response to hormones. In addition, modeling approaches have contributed significantly to exploring how spatio-temporal regulation of hormone signaling contributes to plant growth and patterning. New tools have also been developed to obtain quantitative information on hormone distribution during development and to test model predictions, opening the way for quantitative understanding of the developmental roles of hormones.

  9. Effects of phenobarbital on thyroid hormone contabolism in rat hepatocytes

    EPA Science Inventory

    Hepatic enzyme inducers such as phenobarbital (PB) decrease circulating thyroid hormone (TH) concentrations in rodents. PB induction of hepatic xenobiotic metabolizing enzymes increases thyroid hormones catabolism and biliary elimination. This study examines the catabolism and cl...

  10. Hormone Therapy Won't Help Memory After Menopause

    MedlinePlus

    ... page: https://medlineplus.gov/news/fullstory_159955.html Hormone Therapy Won't Help Memory After Menopause 5-year ... important risk cognitively associated with the use of hormone therapy over at least five years," said lead researcher ...

  11. 'Love Hormone' Gene May Be Key to Social Life

    MedlinePlus

    ... https://medlineplus.gov/news/fullstory_159485.html 'Love Hormone' Gene May Be Key to Social Life Early ... is involved in the production of oxytocin, a hormone linked with a large number of social behaviors ...

  12. Hormone Abuse Prevention and What You Need to Know

    MedlinePlus

    ... y Cuidadores Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types ... Women's Health Hormones and Health Journey Through the Endocrine System Endocrine Disrupting Chemicals (EDCs) Endocrine Glands and Types ...

  13. Preventing Growth Hormone Abuse: An Emerging Health Concern.

    ERIC Educational Resources Information Center

    White, George L.; And Others

    1989-01-01

    Facts about growth hormone abuse should be incorporated into substance abuse components of health education curriculums. Sources, uses, and dangers associated with human growth hormones are discussed. A sample lesson plan is included. (IAH)

  14. Effects of thyroid hormones on the heart.

    PubMed

    Vargas-Uricoechea, Hernando; Bonelo-Perdomo, Anilsa; Sierra-Torres, Carlos Hernán

    2014-01-01

    Thyroid hormones have a significant impact on heart function, mediated by genomic and non-genomic effects. Consequently, thyroid hormone deficiencies, as well as excesses, are expected to result in profound changes in cardiac function regulation and cardiovascular hemodynamics. Thyroid hormones upregulate the expression of the sarcoplasmic reticulum calcium-activated ATPase and downregulate the expression of phospholamban. Overall, hyperthyroidism is characterized by an increase in resting heart rate, blood volume, stroke volume, myocardial contractility, and ejection fraction. The development of "high-output heart failure" in hyperthyroidism may be due to "tachycardia-mediated cardiomyopathy". On the other hand, in a hypothyroid state, thyroid hormone deficiency results in lower heart rate and weakening of myocardial contraction and relaxation, with prolonged systolic and early diastolic times. Cardiac preload is decreased due to impaired diastolic function. Cardiac afterload is increased, and chronotropic and inotropic functions are reduced. Subclinical thyroid dysfunction is relatively common in patients over 65 years of age. In general, subclinical hypothyroidism increases the risk of coronary heart disease (CHD) mortality and CHD events, but not of total mortality. The risk of CHD mortality and atrial fibrillation (but not other outcomes) in subclinical hyperthyroidism is higher among patients with very low levels of thyrotropin. Finally, medications such as amiodarone may induce hypothyroidism (mediated by the Wolff-Chaikoff), as well as hyperthyroidism (mediated by the Jod-Basedow effect). In both instances, the underlying cause is the high concentration of iodine in this medication.

  15. Epilepsy, sex hormones, and antiepileptic drugs.

    PubMed

    Mattson, R H; Cramer, J A

    1985-01-01

    Many factors associated with hormone function have an impact on the course of epilepsy. Patients with epilepsy may have disturbances in sexual function such as anovulatory cycles in women and decreased libido and potency in men. Data indicate seizures, especially those arising in the limbic system, may influence the hypothalamic pituitary axis. Antiepileptic drugs also influence sexual function through direct brain effects as well as through induced changes in pharmacokinetics of the sex steroid hormones. Pregnancy has been reported to be a time of increased seizures; however, this has often been associated with low drug levels, for reasons that include inadequate drug dose, possible changes in pharmacokinetics, and noncompliance. Some evidence suggests that hormones affect seizure frequency. Changes in seizures during the menstrual cycle (catamenial epilepsy) have been found in some women: seizures were fewer during the luteal phase but increased when progesterone levels declined. Some improvement in seizure frequency has been shown in pilot studies using medroxyprogesterone acetate, a synthetic progesterone. Current concepts of the interrelationship among epilepsy, sex hormones, and antiepileptic drugs are discussed.

  16. Hormones, nicotine, and cocaine: clinical studies.

    PubMed

    Mello, Nancy K

    2010-06-01

    Nicotine and cocaine each stimulate hypothalamic-pituitary-adrenal and -gonadal axis hormones, and there is increasing evidence that the hormonal milieu may modulate the abuse-related effects of these drugs. This review summarizes some clinical studies of the acute effects of cigarette smoking or IV cocaine on plasma drug and hormone levels and subjective effects ratings. The temporal covariance between these dependent measures was assessed with a rapid (2 min) sampling procedure in nicotine-dependent volunteers or current cocaine users. Cigarette smoking and IV cocaine each stimulated a rapid increase in LH and ACTH, followed by gradual increases in cortisol and DHEA. Positive subjective effects ratings increased immediately after initiation of cigarette smoking or IV cocaine administration. However, in contrast to cocaine's sustained positive effects (<20 min), ratings of "high" and "rush" began to decrease within one or two puffs of a high-nicotine cigarette while nicotine levels were increasing. Peak nicotine levels increased progressively after each of three successive cigarettes smoked at 60 min intervals, but the magnitude of the subjective effects ratings and peak ACTH and cortisol levels diminished. Only DHEA increased consistently after successive cigarettes. The possible influence of neuroactive hormones on nicotine dependence and cocaine abuse and the implications for treatment of these addictive disorders are discussed.

  17. Antiepileptic drugs, sex hormones, and PCOS.

    PubMed

    Verrotti, Alberto; D'Egidio, Claudia; Mohn, Angelika; Coppola, Giangennaro; Parisi, Pasquale; Chiarelli, Francesco

    2011-02-01

    Reproductive endocrine dysfunction in women with epilepsy is an important issue, and in recent years there is growing evidence to support the effect on sex hormones of both epilepsy per se and various antiepileptic drugs (AEDs). Focal epileptic discharges from the temporal lobe may have a direct influence on the function of the hypothalamic-pituitary axis, thereby altering the release of sex steroid hormones. The role of laterality and severity of epilepsy is still conflicting. The use of the liver enzyme-inducing AEDs--such as phenobarbital, phenytoin, and carbamazepine--can increase serum sex hormone-binding globulin concentrations, leading to diminished bioactivity of testosterone (T) and estradiol. Valproic acid, an enzyme inhibitor, has been associated with the occurrence of reproductive endocrine disorders characterized by high serum T, free androgen index, androstenedione, dehydroepiandrosterone sulfate concentrations, and with polycystic changes in ovaries and menstrual disorders. A better understanding of the effects of AEDs on sex hormones is key to selecting the appropriate AEDs and is crucial for reproductive health in female patients.

  18. Plant Hormones: How They Affect Root Formation.

    ERIC Educational Resources Information Center

    Reinhard, Diana Hereda

    This science study aid, produced by the U.S. Department of Agriculture, includes a series of plant rooting activities for secondary science classes. The material in the pamphlet is written for students and includes background information on plant hormones, a vocabulary list, and five learning activities. Objectives, needed materials, and…

  19. Pharmaceuticals and Hormones in the Environment

    EPA Science Inventory

    Some of the earliest initial reports from Europe and the United States demonstrated that a variety of pharmaceuticals and hormones could be found in surface waters, source waters, drinking water, and influents and effluents from wastewater treatment plants (WWTPs). It is unknown...

  20. Thyroid hormone effect in human hepatocytes.

    PubMed

    Miler, Eliana A; Ríos de Molina, María Del Carmen; Domínguez, Gabriela; Guerra, Liliana N

    2008-01-01

    We have already demonstrated that a combined treatment of methimazole and an antioxidant mixture improved the condition of hyperthyroid patients both biochemically and clinically. Elevated thyroid hormone levels might trigger signs and symptoms of hyperthyroidism through the increase of free radicals. To study the direct effect of thyroid hormone on cellular markers of oxidative stress, we carried out in vitro assays in which 0.1-20.0 nM T3 (6.5-1300.0 ng/dl) doses were added to culture media of the human hepatocyte cell line Hep G2 for 1-24 h. T3 increased malondialdehyde (MDA) and intracellular oxidized glutathione (GSSG) levels; SOD activity was also higher with hormone treatment, whereas catalase and glutathione peroxidase activities showed no variation at different T3 doses and during all experimental times. When ascorbic acid was added to the culture, the MDA level decreased and SOD activity was increased. With higher doses of T3 (e.g. 200 nM), cell death occurred (69% of apoptotic cells). The increase in SOD activity was not enough to overcome the effect of T3 since MDA and GSSG remained high during a 24-h experiment. We showed a beneficial effect of ascorbic acid when cells were exposed to a T3 dose of 20 nM, a higher level of hormone than that achieved in hyperthyroidism. PMID:18647489

  1. Sex Hormone Effects on Body Fluid Regulation

    PubMed Central

    Stachenfeld, Nina S.

    2010-01-01

    In young women, estradiol and progesterone primarily control reproduction, but they also affect fluid regulation. Estradiol lowers the operating point for osmoregulation of arginine vasopressin and thirst and increases plasma volume. Although total body water and sodium content are only mildly affected, data presented in this article suggest that reproductive hormones alter homeostatic set points for body fluid and tonicity. PMID:18580296

  2. Plant hormones and ecophysiology of conifers

    SciTech Connect

    Davies, W.J.

    1995-07-01

    Over the past 30 years, there have been very substantial fluctuations in the interests of plant scientists in the involvement of plant growth regulators in the control of physiology, growth, and development of plants. In the years following the identification of the five major classes of growth regulators and identification of other groups of compounds of somewhat more restricted interest, an enormous number of papers reported the effects of hormones applied externally to a very wide range of plants. During this period, it became very fashionable to compare effects of hormones with the effects of the environment on developmental and physiological phenomena and to suggest a regulatory role for the hormone(s) in the processes under consideration. Ross et al. (1983) have published a very comprehensive survey of the effects of growth regulators applied externally to conifers, and even 10 years later, it is difficult to improve on what they have done. Nevertheless, in the light of recent changes in our understanding of how growth regulators may work, it is necessary to reexamine this field and ask what we really know about the involvement of growth regulators in the ecophysiology of conifers.

  3. Effects of thyroid hormones on the heart.

    PubMed

    Vargas-Uricoechea, Hernando; Bonelo-Perdomo, Anilsa; Sierra-Torres, Carlos Hernán

    2014-01-01

    Thyroid hormones have a significant impact on heart function, mediated by genomic and non-genomic effects. Consequently, thyroid hormone deficiencies, as well as excesses, are expected to result in profound changes in cardiac function regulation and cardiovascular hemodynamics. Thyroid hormones upregulate the expression of the sarcoplasmic reticulum calcium-activated ATPase and downregulate the expression of phospholamban. Overall, hyperthyroidism is characterized by an increase in resting heart rate, blood volume, stroke volume, myocardial contractility, and ejection fraction. The development of "high-output heart failure" in hyperthyroidism may be due to "tachycardia-mediated cardiomyopathy". On the other hand, in a hypothyroid state, thyroid hormone deficiency results in lower heart rate and weakening of myocardial contraction and relaxation, with prolonged systolic and early diastolic times. Cardiac preload is decreased due to impaired diastolic function. Cardiac afterload is increased, and chronotropic and inotropic functions are reduced. Subclinical thyroid dysfunction is relatively common in patients over 65 years of age. In general, subclinical hypothyroidism increases the risk of coronary heart disease (CHD) mortality and CHD events, but not of total mortality. The risk of CHD mortality and atrial fibrillation (but not other outcomes) in subclinical hyperthyroidism is higher among patients with very low levels of thyrotropin. Finally, medications such as amiodarone may induce hypothyroidism (mediated by the Wolff-Chaikoff), as well as hyperthyroidism (mediated by the Jod-Basedow effect). In both instances, the underlying cause is the high concentration of iodine in this medication. PMID:25438971

  4. Growth Hormone Deficiency, Brain Development, and Intelligence

    ERIC Educational Resources Information Center

    Meyer-Bahlburg, Heino F. L.; And Others

    1978-01-01

    Available from: American Medical Association, 535 N. Dearborn Street, Chicago, Illinois 60610. In order to determine what effect, if any, growth hormone (GH) has on human brain development, 29 patients (mean age 11.7 years) with GH deficiency were selected according to the following criteria: no evidence of reversible GH deficiency, onset of…

  5. Human Growth Hormone: The Latest Ergogenic Aid?

    ERIC Educational Resources Information Center

    Cowart, Virginia S.

    1988-01-01

    Believing that synthetic human growth hormone (hGH) will lead to athletic prowess and fortune, some parents and young athletes wish to use the drug to enhance sports performance. Should hGH become widely available, its abuse could present many problems, from potential health risks to the ethics of drug-enhanced athletic performance. (JL)

  6. Prolactin and growth hormone in fish osmoregulation

    USGS Publications Warehouse

    Sakamoto, T.; McCormick, S.D.

    2006-01-01

    Prolactin is an important regulator of multiple biological functions in vertebrates, and has been viewed as essential to ion uptake as well as reduction in ion and water permeability of osmoregulatory surfaces in freshwater and euryhaline fish. Prolactin-releasing peptide seems to stimulate prolactin expression in the pituitary and peripheral organs during freshwater adaptation. Growth hormone, a member of the same family of hormones as prolactin, promotes acclimation to seawater in several teleost fish, at least in part through the action of insulin-like growth factor I. In branchial epithelia, development and differentiation of the seawater-type chloride cell (and their underlying biochemistry) is regulated by GH, IGF-I, and cortisol, whereas the freshwater-type chloride cell is regulated by prolactin and cortisol. In the epithelia of gastrointestinal tract, prolactin induces cell proliferation during freshwater adaptation, whereas cortisol stimulates both cell proliferation and apoptosis. We propose that control of salinity acclimation in teleosts by prolactin and growth hormone primarily involves regulation of cell proliferation, apoptosis, and differentiation (the latter including upregulation of specific ion transporters), and that there is an important interaction of these hormones with corticosteroids. ?? 2005 Elsevier Inc. All rights reserved.

  7. Growth hormone: health considerations beyond height gain

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The therapeutic benefit of growth hormone (GH) therapy in improving height in short children is widely recognized; however, GH therapy is associated with other metabolic actions that may be of benefit in these children. Beneficial effects of GH on body composition have been documented in several dif...

  8. [Lithium induced dysfunction of the parathyroid hormone].

    PubMed

    Valeur, Nana; Andersen, Rikke Steen

    2002-01-28

    The prevalence of hyperparathyroidism (HPT) in patients treated with lithium is higher than that in controls. Lithium seems to affect calcium metabolism, by acting directly parathyroid hormone cells, and distal tubuli in the kidneys. Because hypercalcaemic HPT can cause psychiatric symptoms mistakenly attributed to the lithium treatment, ionised calcium should be a standard control.

  9. THYROID HORMONE DISRUPTION: FROM KINETICS TO DYNAMICS.

    EPA Science Inventory

    A wide range of chemicals with diverse structures act as thyroid disrupting chemicals (TDCs). Broadly defined, TDCs are chemicals that alter the structure or function of the thyroid gland, alter regulatory enzymes associated with thyroid hormones (THs), or change circulating or t...

  10. Evidence for activity-regulated hormone-binding cooperativity across glycoprotein hormone receptor homomers.

    PubMed

    Zoenen, Maxime; Urizar, Eneko; Swillens, Stéphane; Vassart, Gilbert; Costagliola, Sabine

    2012-01-01

    Glycoprotein hormone receptors show strong negative cooperativity. As a consequence, at physiological hormone concentrations, a single agonist binds to a receptor dimer. Here we present evidence that constitutively active receptors lose cooperative allosteric regulation in direct relation with their basal activity. The most constitutive mutants lost nearly all cooperativity and showed an increase of initial tracer binding, reflecting the ability of each protomer to bind with equal affinity. Allosteric interaction between the protomers takes place at the transmembrane domain. The allosteric message resulting from hormone binding to the ectodomain of one protomer travels 'downward' to its transmembrane domain, before affecting the transmembrane domain of the other protomer. This results in transmission of an 'upward' message lowering the binding affinity of the ectodomain of the second protomer. Our results demonstrate a direct relation between the conformational changes associated with activation of the transmembrane domain and the allosteric behaviour of glycoprotein hormone receptors dimers.

  11. Hormones, hormonal agents, and neuropeptides involved in the neuroendocrine regulation of sleep in humans.

    PubMed

    Kotronoulas, Grigorios; Stamatakis, Antonios; Stylianopoulou, Fotini

    2009-01-01

    Sleep is an essential ubiquitous biological process, a periodical state of quiescence in which there is minimal processing of sensory information and no interaction with conspecifics or the environment. Despite relevant research on sleep structure and testing of numerous endogenous sleep-affecting chemicals, questions as to the precise mechanisms and functions of sleep remain without satisfactory responses. The purpose of this review is to report on current evidence as regards the effect of several endogenous and exogenous hormones, hormonal agents, and neuropeptides on sleep onset or wake process, when administered in humans in specific doses and via different routes. The actions of several peptides are presented in detail. Some of them (growth hormone releasing hormone, ghrelin, galanin, neuropeptide Y) seem to promote sleep, whereas others (corticotropin, somatostatin) impair its continuity. PMID:20045796

  12. Neuroendocrine hormones such as growth hormone and prolactin are integral members of the immunological cytokine network.

    PubMed

    Redelman, Doug; Welniak, Lisbeth A; Taub, Dennis; Murphy, William J

    2008-01-01

    Neuroendocrine hormones such as growth hormone (GH) and prolactin (PRL) have been demonstrated to accelerate the recovery of the immune response after chemotherapy and bone marrow transplantation and to enhance the restoration of immunity in individuals infected with HIV and in normal individuals with compromised immune systems associated with aging. As the mechanism of action of these hormones has been elucidated, it has become clear that they are integral members of the immunological cytokine/chemokine network and share regulatory mechanisms with a wide variety of cytokines and chemokines. The members of this cytokine network induce and can be regulated by members of the suppressor of cytokine signaling (SOCS) family of intracellular proteins. In order to take advantage of the potential beneficial effects of hormones such as GH or PRL, it is essential to take into consideration the overall cytokine network and the regulatory effects of SOCS proteins.

  13. SnapShot: Hormones of the gastrointestinal tract.

    PubMed

    Coate, Katie C; Kliewer, Steven A; Mangelsdorf, David J

    2014-12-01

    Specialized endocrine cells secrete a variety of peptide hormones all along the gastrointestinal (GI) tract, making it one of the largest endocrine organs in the body. Nutrients and developmental and neural cues trigger the secretion of gastrointestinal (GI) hormones from specialized endocrine cells along the GI tract. These hormones act in target tissues to facilitate digestion and regulate energy homeostasis. This SnapShot summarizes the production and functions of GI hormones.

  14. Hormones and autoimmunity: animal models of arthritis.

    PubMed

    Wilder, R L

    1996-05-01

    Hormones, particularly those involved in the hypothalamic-pituitary-gonadal and -adrenal axes (HPG and HPA), play important roles in various animal models of autoimmunity such as systemic lupus erythematosus in mice and collagen-induced arthritis (CIA) in mice and rats, and the streptococcal cell wall, adjuvant and avridine arthritis models in rats. Intimately linked to the subject of hormones and autoimmunity are gender, sex chromosomes and age. The importance of these factors in the various animal models is emphasized in this chapter. Several major themes are apparent. First, oestrogens promote B-cell dependent immune-complex mediated disease (e.g. lupus nephritis) but suppress T-cell dependent pathology (CIA in mice and rats), and vice versa. Second, testosterone's effects are complicated and depend on species and disease model. In rats, testosterone suppresses both T-cell and B-cell immunity. In mice, the effects are complex and difficult to interpret, e.g. they tend to enhance CIA arthritis and suppress lupus. Sex chromosome/sex hormone interactions are clearly involved in generating these complicated effects. Third, studies in Lewis and Fischer F344 rats exemplify the importance of corticosteroids, corticotrophin releasing hormone and the HPA axis in the regulation of inflammation and the predisposition to autoimmune diseases. Fourth, the HPA axis is intimately linked to the HPG axis and is sexually dimorphic. Oestrogens stimulate higher corticosteroid responses in females. The animal model data have major implications for understanding autoimmunity in humans. In particular, adrenal and gonadal hormone deficiency is likely to facilitate T-cell dependent diseases like rheumatoid arthritis, while high oestrogen levels or effects, relative to testosterone, are likely to promote B-cell dependent immune-complex-mediated diseases such as lupus nephritis.

  15. Neuropeptides and steroid hormones in arthritis.

    PubMed

    Cerinic, M M; Konttinen, Y; Generini, S; Cutolo, M

    1998-05-01

    Primary afferent nociceptive and peptidergic efferent nerves are sensitized in arthritis and thus easily stimulated by mechanical and chemical stimuli. This leads to increased or disturbed release of neuropeptides from nerve terminals. This local (at the site of stimulation), expanded (expanded and additional receptive fields), and remote (cross-spinal reflexes) neuropeptide release leads to disturbed tissue homeostasis and neurogenic inflammation. In arthritis, raised levels of neuropeptides were detected in the synovial fluid, whereas nerve fibers were lacking in the synovial tissue. It has been hypothesized that cycles of nerve fiber destruction and degeneration follow the cycles of joint inflammation. This evidence suggests that the peripheral nervous system, through its neuropeptides, may contribute to the generation of inflammation, i.e., "neurogenic inflammation." Altered hypothalamic-pituitary-adrenocortical axis function and sex hormone status have been suggested to contribute to the development and persistence of arthritis. In particular, current evidence indicates that glucocorticoid secretion is closely and reciprocally interrelated with inflammation, and that an adrenal insufficiency is present in many forms of immune-mediated arthritis. Conversely, gonadal steroids seem to play a central role as predisposing factors in many forms of arthritis, with estrogens involved as immuno-enhancing hormones and androgens as natural immunosuppressors. Functional receptors for sex hormones have been described in cells involved in the immune response and, after activation, the hormone-receptor complex might modulate the expression of selected cytokines. The possibility of targeting the efferent nerves with specific peptides and replacement therapies with selected steroid hormones may represent a new and potentially efficient and natural system of modulation of the arthritis.

  16. Linker histones in hormonal gene regulation.

    PubMed

    Vicent, G P; Wright, R H G; Beato, M

    2016-03-01

    In the present review, we summarize advances in our knowledge on the role of the histone H1 family of proteins in breast cancer cells, focusing on their response to progestins. Histone H1 plays a dual role in gene regulation by hormones, both as a structural component of chromatin and as a dynamic modulator of transcription. It contributes to hormonal regulation of the MMTV promoter by stabilizing a homogeneous nucleosome positioning, which reduces basal transcription whereas at the same time promoting progesterone receptor binding and nucleosome remodeling. These combined effects enhance hormone dependent gene transcription, which eventually requires H1 phosphorylation and displacement. Various isoforms of histone H1 have specific functions in differentiated breast cancer cells and compact nucleosomal arrays to different extents in vitro. Genome-wide studies show that histone H1 has a key role in chromatin dynamics of hormone regulated genes. A complex sequence of enzymatic events, including phosphorylation by CDK2, PARylation by PARP1 and the ATP-dependent activity of NURF, are required for H1 displacement and gene de-repression, as a prerequisite for further nucleosome remodeling. Similarly, during hormone-dependent gene repression a dedicated enzymatic mechanism controls H1 deposition at promoters by a complex containing HP1γ, LSD1 and BRG1, the ATPase of the BAF complex. Thus, a broader vision of the histone code should include histone H1, as the linker histone variants actively participate in the regulation of the chromatin structure. How modifications of the core histones tails affect H1 modifications and vice versa is one of the many questions that remains to be addressed to provide a more comprehensive view of the histone cross-talk mechanisms.

  17. Growth hormone: its physiology and control.

    PubMed

    Scanes, C G; Lauterio, T J

    1984-12-01

    Growth hormone (GH) is a protein hormone produced by the somatotrophs of the anterior pituitary gland of birds and other vertebrates. The secretion of GH in birds is under hypothalamic control; it involves three peptidergic releasing factors: growth hormone-releasing factor (GRF) (stimulatory); thyrotropin-releasing hormone (TRH) (stimulatory); and somatostatin (SRIF) (inhibitory). In addition, there is evidence for effects of biogenic amines (including serotonin and norepinephrine) and prostaglandins at the level of the hypothalamus and possibly also the pituitary gland. In all avian species examined, plasma concentrations of GH are high in young posthatching chicks but low in the adult and embryo. The difference in plasma concentrations of GH between young and adult birds is due to both greater GH secretion and reduced clearance. The lower secretion of GH in adult birds reflects fewer somatotrophs in the pituitary, changes in somatotroph structure, and reduced GH responses to TRH or GRF administration. There is only limited data on the role of GH in birds. GH appears to be required for normal growth; acting at least in part by increasing somatomedin production. However, plasma concentrations of GH do not necessarily correlate with growth rate. For instance, in chicks with reduced growth rate owing to either goitrogen or protein deficiency in the diet, plasma concentrations of GH are elevated. GH also can influence lipid metabolism by increasing lipolysis, decreasing lipogenesis, and stimulating the uptake of glucose by adipose tissue. The physiological significance of these actions is, however, not established. In addition, GH affects the secretion of other hormones, the immune system, and perhaps also the reproductive system. PMID:6151579

  18. 21 CFR 522.1820 - Pituitary luteinizing hormone for injection.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Pituitary luteinizing hormone for injection. 522... ANIMAL DRUGS § 522.1820 Pituitary luteinizing hormone for injection. (a) Specifications. The drug is a... standard pituitary luteinizing hormone and is reconstituted for use by addition of 5 milliliters of...

  19. 21 CFR 522.1820 - Pituitary luteinizing hormone for injection.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Pituitary luteinizing hormone for injection. 522... ANIMAL DRUGS § 522.1820 Pituitary luteinizing hormone for injection. (a) Specifications. The drug is a... standard pituitary luteinizing hormone and is reconstituted for use by addition of 5 milliliters of...

  20. 21 CFR 522.1002 - Follicle stimulating hormone.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Follicle stimulating hormone. 522.1002 Section 522....1002 Follicle stimulating hormone. (a)(1) Specifications. Each package contains 2 vials. One vial... hormone. The other vial contains 10 milliliters of aqueous diluent. (2) Sponsor. See No. 052923 in §...

  1. 21 CFR 522.1002 - Follicle stimulating hormone.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Follicle stimulating hormone. 522.1002 Section 522....1002 Follicle stimulating hormone. (a)(1) Specifications. Each package contains 2 vials. One vial... hormone. The other vial contains 10 milliliters of aqueous diluent. (2) Sponsor. See No. 052923 in §...

  2. 21 CFR 522.1820 - Pituitary luteinizing hormone for injection.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Pituitary luteinizing hormone for injection. 522... ANIMAL DRUGS § 522.1820 Pituitary luteinizing hormone for injection. (a) Specifications. The drug is a... standard pituitary luteinizing hormone and is reconstituted for use by addition of 5 milliliters of...

  3. 21 CFR 522.1002 - Follicle stimulating hormone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Follicle stimulating hormone. 522.1002 Section 522....1002 Follicle stimulating hormone. (a)(1) Specifications. Each package contains 2 vials. One vial... hormone. The other vial contains 10 milliliters of aqueous diluent. (2) Sponsor. See 059521 in §...

  4. 21 CFR 522.1002 - Follicle stimulating hormone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Follicle stimulating hormone. 522.1002 Section 522....1002 Follicle stimulating hormone. (a)(1) Specifications. Each package contains 2 vials. One vial... hormone. The other vial contains 10 milliliters of aqueous diluent. (2) Sponsor. See No. 052923 in §...

  5. 21 CFR 522.1002 - Follicle stimulating hormone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Follicle stimulating hormone. 522.1002 Section 522....1002 Follicle stimulating hormone. (a)(1) Specifications. Each package contains 2 vials. One vial... hormone. The other vial contains 10 milliliters of aqueous diluent. (2) Sponsor. See No. 052923 in §...

  6. 21 CFR 522.1820 - Pituitary luteinizing hormone for injection.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Pituitary luteinizing hormone for injection. 522... ANIMAL DRUGS § 522.1820 Pituitary luteinizing hormone for injection. (a) Specifications. The drug is a... standard pituitary luteinizing hormone and is reconstituted for use by addition of 5 milliliters of...

  7. Partial end organ resistance to thyroid hormone in congenital hypothyroidism

    PubMed Central

    Connell, John M. C.; McLaren, E. H.

    1981-01-01

    End organ resistance to thyroid hormone has been described for a number of years: the defect may be partial or generalized. A case of partial end organ resistance to thyroid hormone in congenital hypothyroidism is described, with evidence of an alteration in TSH threshold to feedback inhibition by thyroid hormone. The implications of this factor in the management of hypothyroidism are discussed. PMID:7301701

  8. Active immunization to luteinizing hormone releasing hormone to inhibit the induction of mammary tumors in the rat

    SciTech Connect

    Ravdin, P.M.; Jordan, V.C.

    1988-01-01

    Immunization of female rats with a bovine serum albumin-luteinizing hormone releasing hormone conjugate results in suppression of dimethylbenzanthracene mammary tumor incidence. Tumor incidence was 1.3, and 1.29 tumors per rat in bovine serum albumin alone (n = 10) and unimmunized (n = 18) control groups, but no tumors were found in the bovine serum albumin-luteinizing hormone releasing hormone conjugate immunized animals (n = 10). In a second experiment immunization with bovine serum albumin-luteinizing hormone releasing hormone conjugates reduced tumor incidence to 0.3 tumors per rat (n = 10) from the 1.2 tumors per animal seen in the control animals (n = 10) immunized with bovine serum albumin alone. Bovine serum albumin-luteinizing hormone immunization caused the production of anti-LHRH antibodies, an interruption of estrous cycles, lowered serum estradiol and progesterone levels, and atrophy of the ovaries and uteri. Immunization BSA-hormone conjugates is a novel anti-tumor strategy.

  9. A priming effect of gonadotrophin releasing hormone on luteinizing hormone secretion in the boar.

    PubMed Central

    Liptrap, R M; Doble, E

    1982-01-01

    The possibility that gonadotrophin releasing hormone (GnRH) can prime the anterior pituitary to a second dose of GnRH resulting in a greatly enhanced secretion of luteinizing hormone was examined in three adult boars. Four experiments were conducted: saline injection followed one hour later by a second saline injection (control); 1 microgram of synthetic GnRH injection followed one hour later by saline injection; saline injection followed one hour later by GnRH injection; GnRH injection followed one hour later by a second GnRH injection. Immunoassayable levels of plasma luteinizing hormone resulting from GnRH plus GnRH treatment were significantly greater than the sum obtained when values from GnRH plus saline and saline plus GnRH were added. Testosterone values in plasma reached maximal concentrations about 60 minutes after peak values of luteinizing hormone were achieved. The results suggest that the first dose of GnRH, in addition to stimulating release of luteinizing hormone can also sensitize the gonadotrophs to a second dose of GnRH causing a significantly greater release of luteinizing hormone. PMID:6751507

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

    SciTech Connect

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

    2009-08-18

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

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

    PubMed Central

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

    2009-01-01

    Parathyroid hormone-related protein (PTHrP) plays a vital role in the embryonic development of the skeleton and other tissues. When it is produced in excess by cancers it can cause hypercalcemia, and its local production by breast cancer cells has been implicated in the pathogenesis of bone metastasis formation in that disease. Antibodies have been developed that neutralize the action of PTHrP through its receptor, parathyroid hormone receptor 1, without influencing parathyroid hormone action through the same receptor. Such neutralizing antibodies against PTHrP are therapeutically effective in animal models of the humoral hypercalcemia of malignancy and of bone metastasis formation. We have determined the crystal structure of the complex between PTHrP (residues 1–108) and a neutralizing monoclonal anti-PTHrP antibody that reveals the only point of contact is an α-helical structure extending from residues 14–29. Another striking feature is that the same residues that interact with the antibody also interact with parathyroid hormone receptor 1, showing that the antibody and the receptor binding site on the hormone closely overlap. The structure explains how the antibody discriminates between the two hormones and provides information that could be used in the development of novel agonists and antagonists of their common receptor. PMID:19346515

  12. Exogenous Hormone Use: Oral Contraceptives, Postmenopausal Hormone Therapy, and Health Outcomes in the Nurses’ Health Study

    PubMed Central

    Grodstein, Francine; Stampfer, Meir J.; Willett, Walter C.; Hu, Frank B.; Manson, JoAnn E.

    2016-01-01

    Objectives. To review the contribution of the Nurses’ Health Study (NHS) to our understanding of the complex relationship between exogenous hormones and health outcomes in women. Methods. We performed a narrative review of the publications of the NHS and NHS II from 1976 to 2016. Results. Oral contraceptive and postmenopausal hormone use were studied in relation to major health outcomes, including cardiovascular disease and cancer. Current or recent oral contraceptive use is associated with a higher risk of cardiovascular disease (mainly among smokers), melanoma, and breast cancer, and a lower risk of colorectal and ovarian cancer. Although hormone therapy is not indicated primarily for chronic disease prevention, findings from the NHS and a recent analysis of the Women’s Health Initiative indicate that younger women who are closer to menopause onset have a more favorable risk–benefit profile than do older women from use of hormone therapy for relief of vasomotor symptoms. Conclusions. With updated information on hormone use, lifestyle factors, and other variables, the NHS and NHS II continue to contribute to our understanding of the complex relationship between exogenous hormones and health outcomes in women. PMID:27459451

  13. Sex hormones affect neurotransmitters and shape the adult female brain during hormonal transition periods

    PubMed Central

    Barth, Claudia; Villringer, Arno; Sacher, Julia

    2015-01-01

    Sex hormones have been implicated in neurite outgrowth, synaptogenesis, dendritic branching, myelination and other important mechanisms of neural plasticity. Here we review the evidence from animal experiments and human studies reporting interactions between sex hormones and the dominant neurotransmitters, such as serotonin, dopamine, GABA and glutamate. We provide an overview of accumulating data during physiological and pathological conditions and discuss currently conceptualized theories on how sex hormones potentially trigger neuroplasticity changes through these four neurochemical systems. Many brain regions have been demonstrated to express high densities for estrogen- and progesterone receptors, such as the amygdala, the hypothalamus, and the hippocampus. As the hippocampus is of particular relevance in the context of mediating structural plasticity in the adult brain, we put particular emphasis on what evidence could be gathered thus far that links differences in behavior, neurochemical patterns and hippocampal structure to a changing hormonal environment. Finally, we discuss how physiologically occurring hormonal transition periods in humans can be used to model how changes in sex hormones influence functional connectivity, neurotransmission and brain structure in vivo. PMID:25750611

  14. Enzyme immunoassay for rat growth hormone: applications to the study of growth hormone variants

    SciTech Connect

    Farrington, M.A.; Hymer, W.C.

    1987-06-29

    A sensitive and specific competitive enzyme immunoassay (EIA) for rat growth hormone was developed. In this assay soluble growth hormone and growth hormone adsorbed to a solid-phase support compete for monkey anti-growth hormone antibody binding sites. The immobilized antibody-growth hormone complex is detected and quantified using goat anti-monkey immunoglobin G covalently conjugated to horse radish peroxidase. Therefore, a high concentration of soluble growth hormone in the sample will result in low absorbance detection from the colored products of the enzyme reaction. Assay parameters were optimized by investigating the concentration of reagents and the reaction kinetics in each of the assay steps. The assay can be performed in 27 hours. A sensitivity range of 0.19 ng to 25 ng in the region of 10 to 90% binding was obtained. Near 50% binding (3 ng) the intraassay coefficient of variation (CV) was 5.54% and the interassay CV was 5.33%. The correlation coefficient (r/sup 2/) between radioimmunoassay and EIA was 0.956 and followed the curve Y = 0.78X + 1.0. 9 references, 6 figures.

  15. Luteinizing Hormone-Releasing Hormone Distribution in the Anterior Hypothalamus of the Female Rats

    PubMed Central

    Castañeyra-Ruiz, Leandro; González-Marrero, Ibrahim; Castañeyra-Ruiz, Agustín; González-Toledo, Juan M.; Castañeyra-Ruiz, María; de Paz-Carmona, Héctor; Castañeyra-Perdomo, Agustín; Carmona-Calero, Emilia M.

    2013-01-01

    Luteinizing hormone-releasing hormone (LHRH) neurons and fibers are located in the anteroventral hypothalamus, specifically in the preoptic medial area and the organum vasculosum of the lamina terminalis. Most luteinizing hormone-releasing hormone neurons project to the median eminence where they are secreted in the pituitary portal system in order to control the release of gonadotropin. The aim of this study is to provide, using immunohistochemistry and female brain rats, a new description of the luteinizing hormone-releasing hormone fibers and neuron localization in the anterior hypothalamus. The greatest amount of the LHRH immunoreactive material was found in the organum vasculosum of the lamina terminalis that is located around the anterior region of the third ventricle. The intensity of the reaction of LHRH immunoreactive material decreases from cephalic to caudal localization; therefore, the greatest immunoreaction is in the organum vasculosum of the lamina terminalis, followed by the dorsomedial preoptic area, the ventromedial preoptic area, and finally the ventrolateral medial preoptic area, and in fibers surrounding the suprachiasmatic nucleus and subependymal layer on the floor of the third ventricle where the least amount immunoreactive material is found. PMID:25938107

  16. Sex hormone adjuvant therapy in rheumatoid arthritis.

    PubMed

    Cutolo, M

    2000-11-01

    RA is an autoimmune rheumatic disorder resulting from the combination of several predisposing factors, including the relation between epitopes of possible triggering agents and histocompatibility epitopes, the status of the stress response system, and the sex hormone status. Estrogens are implicated as enhancers of humoral immunity, and androgens and progesterone are natural immune suppressors. Sex hormone concentrations have been evaluated in RA patients before glucocorticoid therapy and have frequently been found to be altered, especially in premenopausal women and male patients. In particular, low levels of gonadal and adrenal androgens (testosterone and DHT, DHEA and DHEAS) and a reduced androgen:estrogen ratio have been detected in body fluids (i.e., blood, synovial fluid, smears, saliva) of male and female RA patients. These observations support a possible pathogenic role for the decreased levels of the immune-suppressive androgens. Exposure to environmental estrogens (estrogenic xenobiotics), genetic polymorphisms of genes coding for hormone metabolic enzymes or receptors, and gonadal disturbances related to stress system activation (hypothalamic-pituitary-adrenocortical axis) and physiologic hormonal perturbations such as during aging, the menstrual cycle, pregnancy, the postpartum period, and menopause may interfere with the androgen:estrogen ratio. Sex hormones might exert their immune-modulating effects, at least in RA synovitis, because synovial macrophages, monocytes, and lymphocytes possess functional androgen and estrogen receptors and may metabolize gonadal hormones. The molecular basis for sex hormone adjuvant therapy in RA is thus experimentally substantiated. By considering the well-demonstrated immune-suppressive activities exerted by androgens, male hormones and their derivatives seem to be the most promising therapeutic approach. Recent studies have shown positive effects of androgen replacement therapy at least in male RA patients

  17. Hormonal changes in humans during spaceflight.

    PubMed

    Strollo, F

    1999-01-01

    Readers of this review may feel that there is much more that we do not know about space endocrinology than what we know. Several reasons for this state of affairs have been given: 1. the complexity of the field of endocrinology with its still increasing number of known hormones, releasing factors and precursors, and of the interactions between them through various feedback mechanisms 2. the difficulty in separating the microgravity effects from the effects of stress from launch, isolation and confinement during flight, reentry, and postflight re-adaptation 3. the experimental limitations during flight, such as limited number of subjects, limited number of samples, impossibility of collecting triple samples for pulsatile hormones like growth hormone 4. the disturbing effects of countermeasures used by astronauts 5. the inadequacy of postflight samples for conclusions about inflight values 6. limitations of conclusions from animal experiments and space simulation studies The endocrinology field is divided in to nine systems or axes, which are successively reviewed: 1. Rapid bone demineralization in the early phase of spaceflight that, when unopposed, leads to catastrophic effects after three months but that slows down later. The endocrine mechanism, apart from the effect of exercise as a countermeasure, is not yet understood. 2. The hypothalamic-pituitary-adrenal axis is involved in stress reactions, which complicate our understanding and makes postflight analysis dubious. 3. In the hypothalamic-pituitary-gonadal axis, pulsatility poses a problem for obtaining representative values (e.g., for luteinizing hormone). Reproduction of rats in space is possible, but much more needs to be known about this aspect, particularly in women, before the advent of space colonies, but also in males because some evidence for reversible testicular dysfunction in space has been found. 4. The hypothalamic-pituitary-somato-mammotrophic axis involves prolactin and growth hormone. The

  18. Thyroid hormone receptor binds to a site in the rat growth hormone promoter required for induction by thyroid hormone.

    PubMed Central

    Koenig, R J; Brent, G A; Warne, R L; Larsen, P R; Moore, D D

    1987-01-01

    Transcription of the rat growth hormone (rGH) gene in pituitary cells is increased by addition of thyroid hormone (T3). This induction is dependent on the presence of specific sequences just upstream of the rGH promoter. We have partially purified T3 receptor from rat liver and examined its interaction with these rGH sequences. We show here that T3 receptor binds specifically to a site just upstream of the basal rGH promoter. This binding site includes two copies of a 7-base-pair direct repeat, the centers of which are separated by 10 base pairs. Deletions that specifically remove the T3 receptor binding site drastically reduce response to T3 in transient transfection experiments. These results demonstrate that T3 receptor can recognize specific DNA sequences and suggest that it can act directly as a positive transcriptional regulatory factor. Images PMID:3475698

  19. Luteinizing hormone release and androgen production of avian hybrids in response to luteinizing hormone releasing hormone injection.

    PubMed

    Mathis, G F; Burke, W H; McDougald, L R

    1983-04-01

    The levels of luteinizing hormone (LH) and androgens were measured in sterile avian hybrids. Guinea fowl-chicken and peafowl-guinea fowl hybrids were bled before and after injection with LH- releasing hormone (LHRH). The preinjection LH levels for the guinea fowl-chicken hybrids were below or at the very lower limit of the assay sensitivity and the peafowl-guinea fowl hybrids averaged 1.3 ng/ml. Within 10 min after LHRH injection, LH had increased dramatically in both hybrids and then began to slowly decline. Androgen levels in the guinea fowl-chicken hybrids increased from 16.2 pg/ml to 95.2 pg/ml and continued to increase, reaching 287 pg/ml at the last bleeding 60 min after injection.

  20. Luteinizing hormone release and androgen production of avian hybrids in response to luteinizing hormone releasing hormone injection.

    PubMed

    Mathis, G F; Burke, W H; McDougald, L R

    1983-04-01

    The levels of luteinizing hormone (LH) and androgens were measured in sterile avian hybrids. Guinea fowl-chicken and peafowl-guinea fowl hybrids were bled before and after injection with LH- releasing hormone (LHRH). The preinjection LH levels for the guinea fowl-chicken hybrids were below or at the very lower limit of the assay sensitivity and the peafowl-guinea fowl hybrids averaged 1.3 ng/ml. Within 10 min after LHRH injection, LH had increased dramatically in both hybrids and then began to slowly decline. Androgen levels in the guinea fowl-chicken hybrids increased from 16.2 pg/ml to 95.2 pg/ml and continued to increase, reaching 287 pg/ml at the last bleeding 60 min after injection. PMID:6346309

  1. Thyroid-stimulating Hormone (TSH): Measurement of Intracellular, Secreted, and Circulating Hormone in Xenopus laevis and Xenopus tropicalis.

    EPA Science Inventory

    Thyroid Stimulating Hormone (TSH) is a hormone produced in the pituitary that stimulates the thyroid gland to grow and produce thyroid hormone (TH). The concentration of TH controls developmental changes that take place in a wide variety of organisms. Many use the metaphoric ch...

  2. Luteinizing hormone-releasing hormone induces thyroxine release together with testosterone in the neotenic axolotl Ambystoma mexicanum.

    PubMed

    Jacobs, G F; Kühn, E R

    1988-09-01

    In male neotenic axolotls Ambystoma mexicanum plasma concentrations of thyroxine (T4) and testosterone were increased following intravenous injection of 10 micrograms luteinizing hormone-releasing hormone. A dose of 50 micrograms influenced only plasma T4 levels. This observation suggests for the first time that a hypothalamic hormone is capable of stimulating the thyroidal axis in the neotenic axolotl.

  3. Pathology of excessive production of growth hormone.

    PubMed

    Scheithauer, B W; Kovacs, K; Randall, R V; Horvath, E; Laws, E R

    1986-08-01

    Since its clinical description in the last century, much progress has been made in our understanding of acromegaly. From an initial description of pituitary enlargement as just another manifestation of generalized visceromegaly, the pituitary abnormality has come to be recognized, in most instances, as the underlying aetiological factor. Gigantism and acromegaly are manifestations of disordered pituitary physiology, but the lesion responsible may be hypothalamic, adenohypophyseal or ectopic in location. The best known pathological hypothalamic basis for acromegaly is represented by a neuronal malformation or 'gangliocytoma'. It usually takes the form of an intrasellar gangliocytoma or, more rarely, a hypothalamic hamartoma. The neuronal elaboration of GHRH may play a role in the development of a growth hormone adenoma; the pituitary process may pass through an intermediate stage of somatotropic hyperplasia. When acromegaly has its basis in a pituitary abnormality, the lesion is almost exclusively an adenoma; the non-tumorous adenohypophysis shows no evidence of coexistent hyperplasia. Surprisingly, such tumours are more often engaged in the formation of multiple hormones rather than GH alone. They frequently produce not only GH and prolactin, the products characteristics of cells of the acidophil line, but also glycoprotein hormones, usually TSH. The spectrum of adenomas also varies in its degree of differentiation from a histogenetically primitive lesion, the acidophil stem cell adenoma, to well-differentiated tumours of varying cellular composition and hormone content. Each adenoma type has its clinicopathological, histochemical, immunocytological and ultrastructural characteristics. The isolation and characterization of GHRH has permitted the identification of neuroendocrine tumours, most of foregut origin, elaborating this releasing hormone. Such functional tumours induce hyperplasia of pituitary somatotrophs and may, on occasion, result in the formation of

  4. The use of hormonal agents in the treatment of acne.

    PubMed

    Hassoun, Lauren A; Chahal, Dev S; Sivamani, Raja K; Larsen, Larissa N

    2016-06-01

    Hormones and androgens play an important role in the pathogenesis of acne. Multiple hormonal modulators are now available for the treatment of acne. The efficacies and side effects of currently available hormonal agents are reviewed here including the use of oral contraceptives, spironolactone, flutamide, cyproterone acetate, finasteride, and cortexolone 17α-propionate. Hormonal therapies are an efficacious treatment option for acne among females. With the growing need to reduce antibiotic exposures, hormonal therapies should be more widely studied and incorporated into acne treatment strategies. PMID:27416311

  5. The behavior of renal-regulating hormones during hypogravic stress

    NASA Technical Reports Server (NTRS)

    Leonard, J. I.

    1985-01-01

    The regulation of fluid and electrolyte behavior during space flight is believed to be under control, in large part, of a group of hormones which have their major effects on renal excretion. The hormones studied include renin-angitensin, aldosterone, and antidiuretic hormone (ADH). The regulatory systems of these renal-regulating hormones as they act individually and in concert with each other are analyzed. The analysis is based on simulations of the mathematical model of Guyton. A generalized theory is described which accounts for both short-term and long-term behavior of this set of hormones.

  6. [Growth hormone in children and adolescents: facts and fiction].

    PubMed

    Burckhardt, Marie-Anne; Zumsteg, Urs

    2013-06-19

    Growth Hormone therapy has been used therapeutically for over 50 years. Until recently, growth hormone therapy has been restricted for children and adolescents with proven hypothalamic-pituitary short stature. Today some other causes - but not all - can be treated with growth hormone. To the well-established indications belong apart from proven growth hormone deficiency, children with Turner Syndrome and with Prader Willi Syndrome, children born small for gestational age without catch-up growth and children with chronic kidney disease and with some haematological and oncological diseases. Careful and accurate diagnosis is essential. Growth hormone therapy is rare in everyday practice and requires close cooperation with a pediatric endocrinologist.

  7. The role of hormones in the pathogenesis of psoriasis vulgaris

    PubMed Central

    ROMAN, IULIA IOANA; CONSTANTIN, ANNE-MARIE; MARINA, MIHAELA ELENA; ORASAN, REMUS IOAN

    2016-01-01

    Psoriasis vulgaris is a chronic, common skin disease, which affects the patient’s quality of life to the highest degree. Several exogenous factors and endogenous hormonal changes may act as triggers for psoriasis. The skin possesses a true endocrine system, which is very important in multiple systemic diseases. A number of conditions are associated with psoriasis, and its severity can also be influenced by hormones. Even though the sex hormones and prolactin have a major role in psoriasis pathogenicity, there are a lot of other hormones which can influence the psoriasis clinical manifestations: glucocorticoids, epinephrine, thyroid hormones, and insulin. PMID:27004020

  8. Investigation of sexual dimorphisms through mouse models and hormone/hormone-disruptor treatments.

    PubMed

    Ipulan, Lerrie Ann; Raga, Dennis; Suzuki, Kentaro; Murashima, Aki; Matsumaru, Daisuke; Cunha, Gerald; Yamada, Gen

    2016-01-01

    Sexual dimorphism in mouse reproductive tissues is observable in adult, post-natal, and embryonic stages. The development of sexually dimorphic tissues starts with an ambisexual structure. It is followed by sex-specific organogenesis as guided by different signaling pathways that occur from late embryonic stages. The measurement of the anogenital distance (AGD), and the observation of the external genitalia are practical ways to distinguish male and female pups at birth and thereafter. Careful observation of the morphological or histological features and the molecular signatures of the external genitalia and perineum enable identification of sex or feminization/masculinization of embryos. Aberrations in hormone signaling via castration or treatment with hormones or hormone disruptors result in dysmorphogenesis of reproductive tissues. Several hormone disruptors have been used to modulate different aspects of hormone action through competitive inhibition and exogenous hormone treatment. Concomitantly, the vast advancement of conditional mutant mouse analysis leads to the frequent utilization of Cre recombination technology in the study of reproductive/urogenital tissue development. Mouse Cre-lines that are tissue-specific and cell-specific are also effective tools in identifying the molecular mechanisms during sexually dimorphic development. Cre-lines applicable to different cell populations in the prostate, seminal vesicles, testis and ovaries, and mammary glands are currently being utilized. In the external genitalia and perineum, Cre lines that examine the signaling pathways of cells of endodermal, ectodermal, and mesenchymal origin reveal the roles of these tissues in the development of the external genitalia. The interaction of hormones and growth factors can be examined further through a variety of techniques available for researchers. Such cumulative information about various technologies is summarized. PMID:26651426

  9. The biology of gonadotropin-releasing hormone and its analogs.

    PubMed

    Glode, L M

    1986-01-01

    Gonadotropin-releasing hormone (GnRH) is one of the hormones involved in the complex hypothalamic-pituitary-gonadal axis which regulates the release of testosterone from the testes or estrogen from the ovaries. The development of GnRH analogs has helped elucidate the mechanism of action of the natural hormone, and provided possible new ways to treat hormonally related conditions including hormone-dependent cancers, precocious puberty, and endometriosis. The effectiveness of GnRH agonists in clinical use lies in their ability, with long-term administration, to suppress sex-hormone production. GnRH antagonists may eventually replace agonists because they are able to reduce hormone levels without the initial, temporary rise caused by agonists.

  10. Hormonal effects on Tetrahymena: change in case of combined treatment.

    PubMed

    Csaba, G; Lajkó, Eszter; Pállinger, Eva

    2010-12-01

    In order to approach their natural conditions, populations of Tetrahymena were kept in Losina-Losinky's salt solution for 1 h, than in the tryptone+yeast medium. During this time they were treated with histamine, serotonin or insulin, or with the combinations of these hormones. Effect of the combined treatments on the production of serotonin (5HT), or adrenocorticotropic hormone (ACTH) or triiodothyronine (T₃) by the cells was compared to the effect of single-hormone treatments. Significant differences were seen between the results obtained following the single or combined treatments. There was no summation of the effects, however an elevation or diminution of the hormone production was observed after the combined treatment, as compared with the untreated controls or with the use of one of the hormones in the samples. The experiments demonstrate that there is a hormonal regulation between the Tetrahymena cells and the hormones influence each other's effect. PMID:21183424

  11. Combined hormonal infusion simulates the metabolic response to injury.

    PubMed Central

    Bessey, P Q; Watters, J M; Aoki, T T; Wilmore, D W

    1984-01-01

    To investigate the role of hormones as mediators of the metabolic response to injury, nine normal male volunteers received a continuous 74-hour infusion of the three 'stress' hormones: cortisol, glucagon, and epinephrine. As a control, each subject received a saline infusion during another 4-day period. Diets were constant and matched on both occasions. Hormonal infusion achieved hormone concentrations similar to those seen following mild-moderate injury. With this alteration in the endocrine environment significant hypermetabolism, negative nitrogen and potassium balances, glucose intolerance, hyperinsulinemia, insulin resistance, sodium retention, and peripheral leukocytosis were observed. Additional studies with single hormone infusions indicated that these responses resulted from both additive and synergistic interactions of the hormones. Triple hormone infusion simulated many of the metabolic responses observed following mild-moderate injury and other catabolic illnesses. PMID:6431917

  12. Thyroid hormones and growth in health and disease.

    PubMed

    Tarım, Ömer

    2011-01-01

    Thyroid hormones regulate growth by several mechanisms. In addition to their negative feedback effect on the stimulatory hormones thyrotropin-releasing hormone (TRH) and thyrotropin (TSH), thyroid hormones also regulate their receptors in various physiological and pathological conditions. Up-regulation and down-regulation of the thyroid receptors fine-tune the biological effects exerted by the thyroid hormones. Interestingly, the deiodinase enzyme system is another intrinsic regulator of thyroid physiology that adjusts the availability of thyroid hormones to the tissues, which is essential for normal growth and development. Almost all chronic diseases of childhood impair growth and development. Every disease may have a unique mechanism to halt linear growth, but reduced serum concentration or diminished local availability of thyroid hormones seems to be a common pathway. Therefore, the effects of systemic diseases on thyroid physiology must be taken into consideration in the evaluation of growth retardation in affected children.

  13. CRC handbook of neurohypophyseal hormone analogs. Volume I

    SciTech Connect

    Jost, K.; Lebl, M.; Brtnik, F.

    1987-01-01

    This book is discussed in two parts. Part one discusses Introductory Remarks. Nomenclature. Natural Forms of Neurohypophyseal Hormones. Synthesis, Purification, and Stability of the Neurohypophyseal Hormone Analogs. Isotopically Modified Analogs. Studies of Analogs Using Physiocochemical and Theoretical Methods. Conformational properties of Neurohypophyseal Hormone Analogs in Solution as Determined bu NMR and Laser Raman Spectroscopies. Other Methods used in the Investigation of Neurohypophyseal Hormone Analog Conformations. Conformation Properties of Analogs in Solution as Revealed by Circular Dichroism Spectroscopy. Conformational Energy Calculations. Quantitative Structure Activity Relationships. References. Part 2 discusses The Use of Neurohypophyseal Hormone Analogs in the Study of Neurophysin-Hormone Interactions. Enzymatic Inactivation. Immunochemistry. Studies of Neurohypopophyseal Hormone Activities at the Cellular Level. Fundamental Biological Evaluation. Important Structural Modifications. Noncoded Amino Acids. Modification of ..cap alpha..-Amino Group; 1-Deamino and 1-Hydroxy Analogs. Modifications in the Issulfide Bridge (Carba-Analogs). Modification of Other Functional Groups. Changes in the Backbone. References. Index.

  14. Pneumosinus dilatans multiplex associated with hormonal imbalance

    PubMed Central

    Ushas, P; Ravi, V; Painatt, Jaeson Mohanan; Nair, Preeti P

    2013-01-01

    Pneumosinus dilatans describes an abnormal dilation of one or more paranasal sinuses without radiological evidence of localised bone destruction, hyperostosis or mucous membrane thickening. Dilation of mastoid air cells also occurs rarely along with involvement of paranasal sinuses. This rare combination of unknown aetiology was reported in two cases in the literature and termed ‘Pneumosinus Dilatans Multiplex’ (PSDM). It is usually asymptomatic, and is detected incidentally on plain radiography, CT or MRI. If left untreated, it can further erode the bone leading to complications such as facial asymmetry, neurological disorders and pathological fractures. The aetiology of the condition remains obscure. Various hypotheses proposed are the presence of gas-forming microorganisms, spontaneous drainage of a mucocele, the presence of a one-way valve, dysregulation of hormonal levels leading to a disturbance of osteoblastic and osteoclastic activity. This paper describes a case of PSDM possibly secondary to hormonal disturbance. PMID:23978497

  15. Pneumosinus dilatans multiplex associated with hormonal imbalance.

    PubMed

    Ushas, P; Ravi, V; Painatt, Jaeson Mohanan; Nair, Preeti P

    2013-08-26

    Pneumosinus dilatans describes an abnormal dilation of one or more paranasal sinuses without radiological evidence of localised bone destruction, hyperostosis or mucous membrane thickening. Dilation of mastoid air cells also occurs rarely along with involvement of paranasal sinuses. This rare combination of unknown aetiology was reported in two cases in the literature and termed 'Pneumosinus Dilatans Multiplex' (PSDM). It is usually asymptomatic, and is detected incidentally on plain radiography, CT or MRI. If left untreated, it can further erode the bone leading to complications such as facial asymmetry, neurological disorders and pathological fractures. The aetiology of the condition remains obscure. Various hypotheses proposed are the presence of gas-forming microorganisms, spontaneous drainage of a mucocele, the presence of a one-way valve, dysregulation of hormonal levels leading to a disturbance of osteoblastic and osteoclastic activity. This paper describes a case of PSDM possibly secondary to hormonal disturbance.

  16. [Hormonal changes in inflammatory bowel disease].

    PubMed

    Kollerová, Jana; Koller, Tomáš; Hlavatý, Tibor; Payer, Juraj

    2015-12-01

    Inflammatory bowel disease is often accompanied by extraintestinal manifestations due to a common autoimmune etiopathogenesis, chronic systemic inflammation, frequent nutrition deficits, and the treatment. Endocrine system changes belong to manifestations too. Interaction is mutual, Crohn's disease and ulcerative colitis cause functional and morphological changes of endocrine tissues. On the other hand the endocrine disorders negatively influence the course of bowel disease. In the article we analyze correlation of IBD with gonadal hormone production and fertility, with adrenal function, with the function and morphology of the thyroid, with growth hormone production and growth disorders in children, and with bone mineral density reduction. This topic is not studied enough and needs more analysis and clarification. PMID:27124970

  17. Update: brain and pituitary hormones of lampreys.

    PubMed

    Sower, S A; Kawauchi, H

    2001-06-01

    Lampreys and hagfish of the class Agnatha are of particular importance in understanding endocrinological relationships since they represent the oldest lineages of extant vertebrates which evolved over 550 million years ago. This review briefly summarizes the latest findings on the reproductive endocrinology of the sea lampreys. Since the First International Symposium of Fish Endocrinology in 1988, when virtually little was known of the hypothalamic-pituitary-gonadal axis, substantial new biochemical, molecular, physiological and immunological evidence has now clearly shown that lamprey reproduction is controlled by the neuroendocrine axis. In addition, five brain and six pituitary hormones of lampreys have been identified mainly by Sower and Kawauchi and colleagues between 1986 and 2000. We now hypothesize that lamprey reproduction is a highly synchronized process that is initiated or mediated by a coordination of complex integration of environmental cues and hormonal mechanisms which is broadly similar to that exhibited by gnathostome vertebrates.

  18. The pituitary growth hormone cell in space

    NASA Technical Reports Server (NTRS)

    Hymer, Wesley C.; Grindeland, R.

    1989-01-01

    Growth hormone (GH), produced and secreted from specialized cells in the pituitary gland, controls the metabolism of protein, fat, and carbohydrate. It is also probably involved in the regulation of proper function of bone, muscle and immune systems. The behavior of the GH cell system was studied by flying either isolated pituitary cells or live rats. In the latter case, pituitary GH cells are prepared on return to earth and then either transplanted into hypophysectomized rats or placed into cell culture so that function of GH cells in-vivo vs. in-vitro can be compared. The results from three flights to date (STS-8, 1983; SL-3, 1985; Cosmos 1887, 1987) established that the ability of GH cells to release hormone, on return to earth, is compromised. The mechanism(s) responsible for this attenuation response is unknown. However, the data are sufficiently positive to indicate that the nature of the secretory defect resides directly within the GH cells.

  19. Cross-gender hormone therapy in adolescents.

    PubMed

    Steever, John

    2014-06-01

    Many transgender youth experience significant amounts of emotional distress regarding the incongruence between their internal gender identity and their physical body. Cross-gender hormonal medical treatments, as managed by a multidisciplinary medical/mental health team, assist patients in transitioning to their desired gender by aligning the physical body to match the gender identity. The World Professional Association for Transgender Health Standards of Care and the Endocrine Society's Clinical Practice Guidelines provide a basic road map for practitioners. Expectations of the youth and the concerns of the family must be addressed and the youth psychologically supported during the transition period. Issues around future fertility should be explored as well. The goal of this article is to introduce the general pediatrician to cross-gender hormone treatments, their management, monitoring laboratory tests and clinical effects, and the issues surrounding their use in adolescents.

  20. Electrophysiological responses of osteoclasts to hormones.

    PubMed

    Ferrier, J; Ward, A; Kanehisa, J; Heersche, J N

    1986-07-01

    Electrophysiological measurements were carried out on osteoclasts in vitro. Such isolated osteoclasts are able to resorb bone in vitro and contract in response to calcitonin (CT). Our measurements show that individual osteoclasts respond to CT with a significant transient hyperpolarization of membrane potential. Application of parathyroid hormone (PTH) and dibutyryl cAMP produced a transient hyperpolarization in some osteoclasts. Measurements on an osteoblastlike line (ROS 17/2.8) showed a sustained hyperpolarizing response to CT, which is similar to but smaller than the hyperpolarizing response to PTH and dibutyryl cAMP in this and some other osteoblastlike lines. In contrast to osteoblastlike cells, the osteoclasts have no long term membrane potential response to CT, to PTH, or to dibutyryl cAMP. These results show that there are distinct differences between osteoclasts and osteoblasts in their ion transport responses to hormones.

  1. Venous thromboembolism in women taking hormonal contraceptives.

    PubMed

    Blanco-Molina, Angeles; Monreal, Manuel

    2010-02-01

    Hormonal contraceptives are a popular method of contraception, but their use has been associated with an increased risk for venous thromboembolism. In order to reduce such risk, these compounds have been changed in their dosage, chemical composition and route of administration. The absolute risk of death from pulmonary embolism in contraceptive users has been estimated to be 10.5 (95% CI: 6.2-16.6) per million woman-years. The safest option is an oral contraceptive containing levonorgestrel combined with a low dose of estrogen. Identifying women at increased risk for venous thromboembolism is difficult, and greater use of thromboprophylaxis during immobility or minor surgery should be warranted. Several authors have called for all women to be screened for thrombophilia before prescription of hormonal contraceptives, but its cost-effectiveness remains uncertain.

  2. Futures Challenges in Thyroid Hormone Signaling Research.

    PubMed

    Flamant, Frédéric

    2016-01-01

    The canonical pathway of thyroid hormone signaling involves its binding to nuclear receptors (TRs) acting directly on the transcription of a number of genes. Recent genome-wide studies revealed that chromatin occupancy by TR is not sufficient for transactivation of gene expression. Reciprocally, in some cases, DNA binding by TR may not be required for cellular response. This leaves many new questions to be addressed in future research. PMID:27445973

  3. Hormonal changes during long-term isolation.

    PubMed

    Custaud, M A; Belin de Chantemele, E; Larina, I M; Nichiporuk, I A; Grigoriev, A; Duvareille, M; Gharib, C; Gauquelin-Koch, G

    2004-05-01

    Confinement and inactivity induce considerable psychological and physiological modifications through social and sensory deprivation. The aim of the SFINCSS-99 experiment was to determine the cardiovascular and hormonal pattern of blood volume regulation during long-term isolation and confinement. Simulation experiments were performed in pressurized chambers similar in size to the volumes of modern space vehicles. Group I consisted of four Russian male volunteers, who spent 240 days in a 100-m(3 )chamber. Group II included four males (one German and three Russians) who spent 110 days in isolation (200-m(3) module). The blood samples, taken before, during and after the isolation period, were used to determine haematocrit (Ht), growth hormone (GH), active renin, aldosterone, and osmolality levels. From the urine samples, electrolytes, osmolality, nitrites, nitrates, cortisol, antidiuretic hormone (ADH), aldosterone, normetanephrine and metanephrine levels were determined. The increase in plasma volume (PV) that is associated with a tendency for a decrease in plasma active renin is likely to be due to decreased sympathetic activity, and concords with the changes in urinary catecholamine levels during confinement. Urinary catecholamine levels were significantly higher during the recovery period than during confinement. This suggests that the sympathoadrenal system was activated, and concords with the increase in heart rate. Vascular resistance is determined by not only the vasoconstrictor but also vasodilator systems. The ratio of nitrite/nitrate in urine, as an indicator of nitric oxide release, did not reveal any significant changes. Analysis of data suggests that the duration of the isolation was a main factor involved in the regulation of hormones.

  4. Sex hormones in juvenile nasopharyngeal angiofibroma tissue.

    PubMed

    Kumagami, H

    1993-01-01

    Five cases of juvenile nasopharyngeal angiofibroma were studied in terms of the presence of progesterone, estradiol, testosterone, and dihydrotestosterone in the juvenile nasopharyngeal angiofibroma tissue using the peroxidase-antiperoxidase method. Progesterone and estradiol were positive in all cases. Testosterone was positive in 2 of the 5 patients. Dihydrotestosterone was positive in 3 of the 5 patients. Hormone in the juvenile nasopharyngeal angiofibroma tissue seems to change by the activity of nasopharyngeal angiofibroma.

  5. Futures Challenges in Thyroid Hormone Signaling Research

    PubMed Central

    Flamant, Frédéric

    2016-01-01

    The canonical pathway of thyroid hormone signaling involves its binding to nuclear receptors (TRs) acting directly on the transcription of a number of genes. Recent genome-wide studies revealed that chromatin occupancy by TR is not sufficient for transactivation of gene expression. Reciprocally, in some cases, DNA binding by TR may not be required for cellular response. This leaves many new questions to be addressed in future research. PMID:27445973

  6. Immunoprecipitation of the parathyroid hormone receptor

    SciTech Connect

    Wright, B.S.; Tyler, G.A.; O'Brien, R.; Caporale, L.H.; Rosenblatt, M.

    1987-01-01

    An /sup 125/I-labeled synthetic analog of bovine parathyroid hormone, (8-norleucine,18-norleucine,34-tyrosine)PTH-(1-34) amide ((Nle)PTH-(1-34)-NH/sub 2/), purified by high-pressure liquid chromatography (HPLC), was employed to label the parathyroid hormone (PTH) receptor in cell lines derived from PTH target tissues: the ROS 17/2.8 rat osteosarcoma of bone and the CV1 and COS monkey kidney lines. After incubation of the radioligand with intact cultured cells, the hormone was covalently attached to receptors by using either a photoaffinity technique or chemical (affinity) crosslinking. In each case, covalent labeling was specific, as evidenced by a reduction of labeling when excess competing nonradioactive ligand was present. After covalent attachment of radioligand, membranes were prepared form the cells and solubilized in the nonionic detergent Nonidet P-40 or octyl glucoside. Analysis of the immunoprecipitate on NaDod-SO/sub 4//polyacrylamide gel electrophoresis followed by autoradiography revealed the presence of a doublet of apparent molecular mass 69-70 kDa. Specifically labeled bands of approximate molecular mass 95 and 28 kDa were also observed. The anti-PTH IgG was affinity purified by passage over a PTH-Sepharose column and used to made an immunoaffinity column. These studies suggest that the use of an anti-PTH antiserum that binds receptor-bound hormone is likely to be a useful step in the further physicochemical characterization and purification of the PTH receptor.

  7. Christmas: an event driven by our hormones?

    PubMed

    Ludwig, M

    2011-12-01

    No other event in the Christian calendar has such a deep impact on our behaviour as the annual event called Christmas. Christmas is not just 'Christmas Day'; indeed, it is a long developmental rhythm with a period of almost exactly 365 days. Here, I describe the neuronal and hormonal changes and their effects on our behaviour during the preparation and the execution of the event(1) .

  8. Thyroid Hormone Signaling and Cone Photoreceptor Viability.

    PubMed

    Ma, Hongwei; Ding, Xi-Qin

    2016-01-01

    Thyroid hormone (TH) signaling regulates cell proliferation, differentiation, and apoptosis. In the retina, TH signaling plays a central role in cone opsin expression. TH signaling inhibits S opsin expression, stimulates M opsin expression, and promotes dorsal-ventral opsin patterning. TH signaling has also been associated with cone photoreceptor viability. Treatment with thyroid hormone triiodothyronine (T3) or induction of high T3 by deleting the hormone-inactivating enzyme type 3 iodothyronine deiodinase (DIO3) causes cone death in mice. This effect is reversed by deletion of the TH receptor (TR) gene. Consistent with the T3 treatment effect, suppressing TH signaling preserves cones in mouse models of retinal degeneration. The regulation of cone survival by TH signaling appears to be independent of its regulatory role in cone opsin expression. The mechanism by which TH signaling regulates cone viability remains to be identified. The current understanding of TH signaling regulation in photoreceptor viability suggests that suppressing TH signaling locally in the retina may represent a novel strategy for retinal degeneration management. PMID:26427466

  9. Internet informs parents about growth hormone

    PubMed Central

    Cousounis, Pamela; Lipman, Terri H.; Ginsburg, Kenneth; Grimberg, Adda

    2013-01-01

    Background Parent knowledge influences decisions regarding medical care for their children. Methods Parents of pediatric primary care patients aged 9-14 years, irrespective of height, participated in open focus groups (OFG). Moderators asked, “How do people find out about growth hormone (GH)?” Because many parents cited the Internet, the top 10 results from the Google searches, growth hormone children and parents of children who take growth hormone, were examined as representative. Three investigators independently performed content analysis, then reached consensus. Results were tabulated via summary statistics. Results Eighteen websites were reviewed, most with the purpose of education (56%) and many funded by commercial sources (44%). GH treatment information varied, with 33% of sites containing content only about U.S Food and Drug Administration-approved indications. Fifty-six percent of sites included information about psychosocial benefits from treatment, 44% acknowledging them as controversial. Although important to OFG participants, risks and costs were each omitted from 39% of websites. Conclusion Parents often turn to the Internet for GH-related information for their children, though its content may be incomplete and/or biased. Clinicians may want to provide parents with tools for critically evaluating Internet-based information, a list of pre-reviewed websites, or their own educational materials. PMID:23942255

  10. Multiple hormone deficiencies in children with hemochromatosis.

    PubMed

    Oerter, K E; Kamp, G A; Munson, P J; Nienhuis, A W; Cassorla, F G; Manasco, P K

    1993-02-01

    Patients with thalassemia major require multiple blood transfusions leading to hemochromatosis. These patients often have pubertal delay and growth failure, the etiology of which has not been fully elucidated. We performed an extensive endocrine evaluation which included measurements of spontaneous and stimulated levels of gonadotropins, GH, thyroid hormone, and adrenal hormones in 17 patients between the ages of 12 and 18 yr with hemochromatosis receiving desferoxamine therapy. All of the 17 patients had at least one endocrine abnormality, and 12 had more than one abnormality. Abnormalities of the hypothalamic-pituitary-gonadal axis were the most common. Six patients had clinical evidence of delayed puberty with spontaneous and stimulated gonadotropin and sex steroid levels appropriate for their delayed pubertal stage. All 14 children in puberty LH pulsatility index below the mean for pubertal stage compared to normal children. Six of the 14 had LH pulsatility index more than 2 SD below the mean for pubertal stage. This may be an indicator of abnormal pituitary function. Six patients failed either the provocative GH tests (peak GH < 7 micrograms/L) or had a mean spontaneous GH less than 1 microgram/L. The 4 patients who failed provocative tests had growth velocities more than 2 SD below the mean for bone age. Three patients had evidence of primary hypothyroidism. We conclude that all patients with hemochromatosis need periodic careful endocrine evaluations because the incidence of endocrine dysfunction is substantial and they may benefit from hormonal therapy.

  11. Effects of hypothalamic dopamine on growth hormone-releasing hormone-induced growth hormone secretion and thyrotropin-releasing hormone-induced prolactin secretion in goats.

    PubMed

    Jin, Jin; Hashizume, Tsutomu

    2015-06-01

    The aim of the present study was to clarify the effects of hypothalamic dopamine (DA) on the secretion of growth hormone (GH) in goats. The GH-releasing response to an intravenous (i.v.) injection of GH-releasing hormone (GHRH, 0.25 μg/kg body weight (BW)) was examined after treatments to augment central DA using carbidopa (carbi, 1 mg/kg BW) and L-dopa (1 mg/kg BW) in male and female goats under a 16-h photoperiod (16 h light, 8 h dark) condition. GHRH significantly and rapidly stimulated the release of GH after its i.v. administration to goats (P < 0.05). The carbi and L-dopa treatments completely suppressed GH-releasing responses to GHRH in both male and female goats (P < 0.05). The prolactin (PRL)-releasing response to an i.v. injection of thyrotropin-releasing hormone (TRH, 1 μg/kg BW) was additionally examined in male goats in this study to confirm modifications to central DA concentrations. The treatments with carbi and L-dopa significantly reduced TRH-induced PRL release in goats (P < 0.05). These results demonstrated that hypothalamic DA was involved in the regulatory mechanisms of GH, as well as PRL secretion in goats.

  12. Sex hormones in the cardiovascular system.

    PubMed

    dos Santos, Roger Lyrio; da Silva, Fabrício Bragança; Ribeiro, Rogério Faustino; Stefanon, Ivanita

    2014-05-01

    Gender-associated differences in the development of cardiovascular diseases have been described in humans and animals. These differences could explain the low incidence of cardiovascular disease in women in the reproductive period, such as stroke, hypertension, and atherosclerosis. The cardiovascular protection observed in females has been attributed to the beneficial effects of estrogen on endothelial function. Besides estrogen, sex hormones are able to modulate blood pressure by acting on important systems as cardiovascular, renal, and neural. They can have complementary or antagonistic actions. For example, testosterone can raise blood pressure by stimulating the renin-angiotensin-aldosterone system, whereas estrogen alone or combined with progesterone has been associated with decreased blood pressure. The effects of testosterone in the development of cardiovascular disease are contradictory. Although some researchers suggest a positive effect, others indicate negative actions of testosterone. Estrogens physiologically stimulate the release of endothelium-derived vasodilator factors and inhibit the renin-angiotensin system. Although the cardioprotective effects of estrogen are widely appreciated, little is known about the effects of progesterone, which is commonly used in hormone replacement therapy. Progesterone has both vasodilatory and vasoconstrictive effects in the vasculature, depending on the location of the vessel and the level of exposure. Nevertheless, the mechanisms through which sex hormones modulate blood pressure have not been fully elucidated. Therefore, the characterization of those could lead to a better understanding of hypertension in women and men and perhaps to improved forms of therapy.

  13. [Regulation of SWS by hormones and cytokines].

    PubMed

    Li, L H; Ku, B S

    2000-01-01

    SWS is the most important component of sleep. (1) VLPO-TMN seems to generate sleep and wakefulness. The rostral basal forebrain, which was defined as PGD2-SPZ, may be involved in regulation of sleep. (2) PGD2 promotes sleep, especially SWS, while PGE2 prolongs wakefulness and depresses both SWS and REMS. (3) During SWS the activation of hypothalamus-pituitary-adrenocortic axis is inhibited, while the release of growth hormone is accelerated. The soporific effects of melatonin may be attributed to its hypothermic effects. (4) Interleukin-1 prolongs sleep, especially SWS, which seems to be mediated by PGD2. Tumor necrosis factor (TFN) may promote SWS through 5-HT and its receptor. Therefore, the development of new hypnotics, which selectively prolong SWS, might follow the following ways: PGD2 and chemicals which act like PGD2; immuno-regulators; substances with effects on 5-HT receptors; hormone, such as melatonin and growth hormone, which play roles in the physiological regulation on sleep-wakefulness. PMID:12532764

  14. Active acromegaly enhances spontaneous parathyroid hormone pulsatility.

    PubMed

    Mazziotti, Gherardo; Cimino, Vincenzo; De Menis, Ernesto; Bonadonna, Stefania; Bugari, Giovanna; De Marinis, Laura; Veldhuis, Johannes D; Giustina, Andrea

    2006-06-01

    In healthy subjects, parathyroid hormone (PTH) is secreted in a dual fashion, with low-amplitude and high-frequency pulses superimposed on tonic secretion. These 2 components of PTH secretion seem to have different effects on target organs. The aim of our study was to evaluate whether growth hormone excess in acromegaly may modify the spontaneous pulsatility of PTH. Five male patients with newly diagnosed active acromegaly and 8 healthy subjects were evaluated by 3-minute blood sampling for 6 hours. Plasma PTH concentrations were evaluated by multiparameter deconvolution analysis. Plasma PTH release profiles were also subjected to an approximate entropy (ApEn) estimate, which provides an ensemble measure of the serial regularity or orderliness of the release process. In acromegalic patients, baseline serum PTH values were not significantly different from those measured in the healthy subjects, as well as tonic PTH secretion rate, number of bursts, fractional pulsatile PTH secretion, and ApEn ratio. Conversely, PTH pulse half-duration was significantly longer in acromegalic patients vs healthy subjects (11.8+/-0.95 vs 6.9+/-1.6 minutes; P=.05), whereas PTH pulse mass showed a tendency (P=.06) to be significantly greater in acromegalic patients. These preliminary data suggest that growth hormone excess may affect PTH secretory dynamics in patients with acromegaly. Potentially negative bone effects of the modifications of PTH secretory pattern in acromegaly should be investigated.

  15. [Hormonal factors in etiology of common acne].

    PubMed

    Bergler-Czop, Beata; Brzezińska-Wcisło, Ligia

    2004-05-01

    Common acne is steatorrhoeic chronic disease, to which specific is, among others, the presence of blackheads, papulopustular eruptions, purulent cysts and cicatrices. Such hormonal factors belong to elements inherent in etiology of the affection. Sebaceous glands have cell receptors on their surface for androgens. In etiopathogenesis of common/simple acne, a decisive role is played by a derivative of testosterone, i.e. 5-alpha-dihydrotestosterone (DHT). However, some experts are of opinion that there is no correlation between the increased intensity of common acne and other symptoms of hyperandrogenism. Numerous authors assume, however, that common acne-affected patients may be sometimes subjected to intense reactions caused by sebaceous glands against physiological androgens concentrations. Naturally, estrogens can inhibit release of such androgens. Under physiological conditions, natural progesterone does not conduct to intensification of the seborrhea, but the activity of sebum secretion may be triggered off by its synthetic counterparts. Hormonal etiology can be very distinctly visible in the steroid, androgenic, premenstrual, menopausal acne, as well as in juvenile acne and acne neonatorum. In case of females affected by acne, hormonal therapy should be persistently supported and consulted with dermatologists, endocrinologists and gynecologists. Antiandrogenic preparations are applied, such as: cyproterone acetate concurrently administered with estrogens and, as well as not so frequently with chlormadinone acetate (independently or during estrogenic therapy). PMID:15518435

  16. Vitamin D, steroid hormones, and autoimmunity.

    PubMed

    Cutolo, Maurizio; Paolino, Sabrina; Sulli, Alberto; Smith, Vanessa; Pizzorni, Carmen; Seriolo, Bruno

    2014-05-01

    The endogenous serum metabolite of vitamin D (calcitriol, 1,25(OH)2 D3 ) is considered a true steroid hormone (D hormone), and like glucocorticoids (GCs) and gonadal hormones, may exert several immunomodulatory activities. Serum vitamin D deficiency (25(OH) D), and therefore reduced 1,25(OH)2 D3 availability, is considered a risk factor for several chronic/inflammatory or autoimmune conditions, including infectious diseases, type 1 diabetes, multiple sclerosis, and especially autoimmune rheumatic diseases (ARD). In ARD in particular, 1,25(OH)2 D3 regulates both innate and adaptive immunity, potentiating the innate response (antimicrobial activity) but reducing adaptive immunity (antigen presentation, T and B cell activities). Regarding a possible synergism between vitamin D and GCs, several studies show that 1,25(OH)2 D3 has significant additive effects on dexamethasone-mediated inhibition of human lymphocyte and monocyte proliferation. Conversely, vitamin D deficiency seems to play a role in increasing autoantibody production by B cells, and seasonal vitamin D declines may trigger flares in ARD, as recently shown. Finally, 1,25(OH)2 D3 seems to reduce aromatase activity and limit the negative effects related to increased peripheral estrogen metabolism (cell proliferation, B cell overactivity).

  17. Thyroid Hormone and Leptin in the Testis

    PubMed Central

    Ramos, Cristiane Fonte; Zamoner, Ariane

    2014-01-01

    Leptin is primarily expressed in white adipose tissue; however, it is expressed in the hypothalamus and reproductive tissues as well. Leptin acts by activating the leptin receptors (Ob-Rs). Additionally, the regulation of several neuroendocrine and reproductive functions, including the inhibition of glucocorticoids and enhancement of thyroxine and sex hormone concentrations in human beings and mice are leptin functions. It has been suggested that thyroid hormones (TH) could directly regulate leptin expression. Additionally, hypothyroidism compromises the intracellular integration of leptin signaling specifically in the arcuate nucleus. Two TH receptor isoforms are expressed in the testis, TRa and TRb, with TRa being the predominant one that is present in all stages of development. The effects of TH involve the proliferation and differentiation of Sertoli and Leydig cells during development, spermatogenesis, and steroidogenesis. In this context, TH disorders are associated with sexual dysfunction. An endocrine and/or direct paracrine effect of leptin on the gonads inhibits testosterone production in Leydig cells. Further studies are necessary to clarify the effects of both hormones in the testis during hypothyroidism. The goal of this review is to highlight the current knowledge regarding leptin and TH in the testis. PMID:25505448

  18. The current state of male hormonal contraception.

    PubMed

    Chao, Jing H; Page, Stephanie T

    2016-07-01

    World population continues to grow at an unprecedented rate, doubling in a mere 50years to surpass the 7-billion milestone in 2011. This steep population growth exerts enormous pressure on the global environment. Despite the availability of numerous contraceptive choices for women, approximately half of all pregnancies are unintended and at least half of those are unwanted. Such statistics suggest that there is still a gap in contraceptive options for couples, particularly effective reversible contraceptives for men, who have few contraceptive choices. Male hormonal contraception has been an active area of research for almost 50years. The fundamental concept involves the use of exogenous hormones to suppress endogenous production of gonadotropins, testosterone, and downstream spermatogenesis. Testosterone-alone regimens are effective in many men but high dosing requirements and sub-optimal gonadotropin suppression in 10-30% of men limit their use. A number of novel combinations of testosterone and progestins have been shown to be more efficacious but still require further refinement in delivery systems and a clearer understanding of the potential short- and long-term side effects. Recently, synthetic androgens with both androgenic and progestogenic activity have been developed. These agents have the potential to be single-agent male hormonal contraceptives. Early studies of these compounds are encouraging and there is reason for optimism that these may provide safe, reversible, and reliable contraception for men in the near future. PMID:27016468

  19. Gravitational effects on plant growth hormone concentration

    NASA Astrophysics Data System (ADS)

    Bandurski, Robert S.; Schulze, Aga

    Numerous studies, particularly those of H. Dolk in the 1930's, established by means of bio-assay, that more growth hormone diffused from the lower, than from the upper side of a gravity-stimulated plant shoot. Now, using an isotope dilution assay, with 4,5,6,7 tetradeutero indole-3-acetic acid as internal standard, and selected ion monitoring-gas chromatography-mass spectrometry as the method of determination, we have confirmed Dolk's finding and established that the asymmetrically distributed hormone is, in fact, indole-3-acetic acid (IAA). This is the first physico-chemical demonstration that there is more free IAA on the lower sides of a geo-stimulated plant shoot. We have also shown that free IAA occurs primarily in the conductive vascular tissues of the shoot, whereas IAA esters predominate in the growing cortical cells. Now, using an especially sensitive gas chromatographic isotope dilution assay we have found that the hormone asymmetry also occurs in the non-vascular tissue. Currently, efforts are directed to developing isotope dilution assays, with picogram sensitivity, to determine how this asymmetry of IAA distribution is attained so as to better understand how the plant perceives the geo-stimulus.

  20. Exercise and the Regulation of Endocrine Hormones.

    PubMed

    Hackney, Anthony C; Lane, Amy R

    2015-01-01

    The endocrine system has profound regulatory effects within the human body and thus the ability to control and maintain appropriate function within many physiological systems (i.e., homeostasis). The hormones associated with the endocrine system utilize autocrine, paracrine, or endocrine actions on the cells of their target tissues within these physiologic systems to adjust homeostasis. The introduction of exercise as a stressor to disrupt homeostasis can greatly amplify and impact the actions of these hormones. To that end, the endocrine response to an acute exercise session occurs in a progression of phases with the magnitude of the response being relative to the exercise work intensity or volume. Various physiologic mechanisms are considered responsible for these responses, although not all are completely understood or elucidated. Chronic exercise training does not eliminate the acute exercise response but may attenuate the overall effect of the responsiveness as the body adapts in a positive fashion to the training stimulus. Regrettably, an excessive intensity and/or volume of training may lead to maladaptation and is associated with inappropriate endocrine hormonal responses. The mechanisms leading to a deleterious maladaptive state are not well understood and require additional research for elucidation. PMID:26477919

  1. Sex disparity in colonic adenomagenesis involves promotion by male hormones, not protection by female hormones

    PubMed Central

    Amos-Landgraf, James M.; Heijmans, Jarom; Wielenga, Mattheus C. B.; Dunkin, Elisa; Krentz, Kathy J.; Clipson, Linda; Ederveen, Antwan G.; Groothuis, Patrick G.; Mosselman, Sietse; Muncan, Vanesa; Hommes, Daniel W.; Shedlovsky, Alexandra; Dove, William F.; van den Brink, Gijs R.

    2014-01-01

    It recently has been recognized that men develop colonic adenomas and carcinomas at an earlier age and at a higher rate than women. In the ApcPirc/+ (Pirc) rat model of early colonic cancer, this sex susceptibility was recapitulated, with male Pirc rats developing twice as many adenomas as females. Analysis of large datasets revealed that the ApcMin/+ mouse also shows enhanced male susceptibility to adenomagenesis, but only in the colon. In addition, WT mice treated with injections of the carcinogen azoxymethane (AOM) showed increased numbers of colonic adenomas in males. The mechanism underlying these observations was investigated by manipulation of hormonal status. The preponderance of colonic adenomas in the Pirc rat model allowed a statistically significant investigation in vivo of the mechanism of sex hormone action on the development of colonic adenomas. Females depleted of endogenous hormones by ovariectomy did not exhibit a change in prevalence of adenomas, nor was any effect observed with replacement of one or a combination of female hormones. In contrast, depletion of male hormones by orchidectomy (castration) markedly protected the Pirc rat from adenoma development, whereas supplementation with testosterone reversed that effect. These observations were recapitulated in the AOM mouse model. Androgen receptor was undetectable in the colon or adenomas, making it likely that testosterone acts indirectly on the tumor lineage. Our findings suggest that indirect tumor-promoting effects of testosterone likely explain the disparity between the sexes in the development of colonic adenomas. PMID:25368192

  2. Characterization of cDNA for precursor of human luteinizing hormone releasing hormone.

    PubMed

    Seeburg, P H; Adelman, J P

    Human reproduction is controlled by the hypothalamic-pituitary-gonadal axis laid down early in fetal development. Luteinizing hormone releasing hormone (LHRH), also termed gonadotropin releasing hormone (GnRH), is a decapeptide and is a key molecule in this control circuit. It is produced by hypothalamic neurones, secreted in a pulsatile manner into the capillary plexus of the median eminence and effects the release of luteinizing hormone and follicle stimulating hormone from gonadotropic cells in the anterior pituitary. The peptide may have further functions, including behavioural ones, as LHRH or LHRH-like immunoreactivity has been found in gonadal tissue, placenta and the central nervous system, and exogenously administered LHRH is shown to affect behaviour. To investigate the biosynthesis of LHRH, we have now isolated cloned genomic and cDNA sequences encoding the precursor form of LHRH, the existence of which had been suggested from chromatographic studies of hypothalamic and placental extracts. These DNA sequences code for a protein of 92 amino acids in which the LHRH decapeptide is preceded by a signal peptide of 23 amino acids and followed by a Gly-Lys-Arg sequence, as expected for enzymatic cleavage of the decapeptide from its precursor and amidation of the carboxy-terminal of LHRH.

  3. The role of testicular hormones and luteinizing hormone in spatial memory in adult male rats.

    PubMed

    McConnell, Sarah E A; Alla, Juliet; Wheat, Elizabeth; Romeo, Russell D; McEwen, Bruce; Thornton, Janice E

    2012-04-01

    Attempts to determine the influence of testicular hormones on learning and memory in males have yielded contradictory results. The present studies examined whether testicular hormones are important for maximal levels of spatial memory in young adult male rats. To minimize any effect of stress, we used the Object Location Task which is a spatial working memory task that does not involve food or water deprivation or aversive stimuli for motivation. In Experiment 1 sham gonadectomized male rats demonstrated robust spatial memory, but gonadectomized males showed diminished spatial memory. In Experiment 2 subcutaneous testosterone (T) capsules restored spatial memory performance in gonadectomized male rats, while rats with blank capsules demonstrated compromised spatial memory. In Experiment 3, gonadectomized male rats implanted with blank capsules again showed compromised spatial memory, while those with T, dihydrotestosterone (DHT), or estradiol (E) capsules demonstrated robust spatial memory, indicating that T's effects may be mediated by its conversion to E or to DHT. Gonadectomized male rats injected with Antide, a gonadotropin-releasing hormone receptor antagonist which lowers luteinizing hormone levels, also demonstrated spatial memory, comparable to that shown by T-, E-, or DHT-treated males. These data indicate that testicular androgens are important for maximal levels of spatial working memory in male rats, that testosterone may be converted to E and/or DHT to exert its effects, and that some of the effects of these steroid hormones may occur via negative feedback effects on LH.

  4. Endocrine interactions between plants and animals: Implications of exogenous hormone sources for the evolution of hormone signaling.

    PubMed

    Miller, Ashley E M; Heyland, Andreas

    2010-05-01

    Hormones are central to animal physiology, metabolism and development. Details on signal transduction systems and regulation of hormone synthesis, activation and release have only been studied for a small number of animal groups, notably arthropods and chordates. However, a significant body of literature suggests that hormonal signaling systems are not restricted to these phyla. For example, work on several echinoderm species shows that exogenous thyroid hormones (THs) affect larval development and metamorphosis and our new data provide strong evidence for endogenous synthesis of THs in sea urchin larvae. In addition to these endogenous sources, these larvae obtain THs when they consume phytoplankton. Another example of an exogenously acquired hormone or their precursors is in insect and arthropod signaling. Sterols from plants are essential for the synthesis of ecdysteroids, a crucial group of insect morphogenic steroids. The availability of a hormone or hormone precursor from food has implications for understanding hormone function and the evolution of hormonal signaling in animals. For hormone function, it creates an important link between the environment and the regulation of internal homeostatic systems. For the evolution of hormonal signaling it helps us to better understand how complex endocrine mechanisms may have evolved.

  5. The dynamic and static modification of the epigenome by hormones: a role in the developmental origin of hormone related cancers.

    PubMed

    Chiam, Karen; Tilley, Wayne D; Butler, Lisa M; Bianco-Miotto, Tina

    2009-04-01

    There are numerous diseases associated with abnormal hormonal regulation and these include cancers of the breast and prostate. There is substantial evidence that early hormonal perturbations (in utero or during early development) are associated with increased disease susceptibility later in life. These perturbations may arise from exposure to environmental agents or endocrine disruptors which mimic hormones and disrupt normal hormonal signaling. Epigenetic alterations have often been proposed as the underlying mechanism by which early hormonal perturbations may give rise to disease in adulthood. Currently, there is minimal evidence to support a direct link between early hormonal perturbations and epigenetic modifications; or between epigenetic alterations and subsequent onset of cancer. Given that epigenetic modifications may play an important role in hormone-dependent cancers, it is essential to better understand the relationship between the hormonal environment and epigenetic modifications in both normal and disease states. In this review, we highlight several important studies which support the hypothesis that: hormonal perturbations early in life may result in epigenetic changes that may modify hormone receptor function, thereby contributing to an increased risk of developing hormone-related cancers.

  6. Partial Target Organ Resistance to Thyroid Hormone

    PubMed Central

    Bode, Hans Henning; Danon, Marco; Weintraub, Bruce D.; Maloof, Farahe; Crawford, John D.

    1973-01-01

    An 8-year old boy with a small goiter, normal basal metabolic rate (BMR), and elevated serum thyroid hormone levels (thyroxine [T4] 19.5 μg per 100 ml, free T4 4 ng per 100 ml, triiodothyronine [T3] 505 ng per 100 ml) was studied. He had measurable serum thyroid-stimulating hormone (TSH) levels (average 5.5 μU per ml), and the thyroxine-binding proteins, hearing, and epiphyseal structures were normal. There was no parental consanguinity nor were there thyroid abnormalities either in the parents or six siblings. Methimazole, 50 mg daily, depressed thyroxine synthesis (T4 10.5, free T4 2.5) and caused a rise in TSH to 11 μU per ml. After discontinuation of treatment, TSH declined to 4.2 μU per ml and chemical hyperthyroidism returned (T4 21.0 μg per 100 ml, free T4 4.2, and total T3 475 ng per 100 ml, radioactive iodine [RAI] uptake 68%), but studies of BMR and insensible water loss showed the patient to be clinically euthyroid. Thyrotropin-releasing hormone (TRH), 200 μg i.v., caused a brisk rise in TSH to 28 μU per ml, with T4 rising to 28 μg per 100 ml, free T4 to 5.6, and T3 to 730 ng per 100 ml, thus indicating that the pituitary-thyroid system was intact and that the patient's TSH was biologically active. The unusual sensitivity of the pituitary cells to TRH in spite of the markedly elevated serum thyroid hormone levels also suggested that the pituitary was insensitive to suppression by T3 or T4. Serum dilution studies gave immunochemical evidence that this patient's TSH was normal. Neither propranolol, 60 mg, chlorpromazine, 30 mg, nor prednisone, 15 mg daily, influenced thyroid indices. Steroid treatment, however, suppressed the pituitary response to TRH, T3 in doses increased over a period of 12 days to as much as 150 μg daily caused a rise in serum T3 to above 800 ng per 100 ml, a decline of T4 to euthyroid levels (T4 9.5 μg per 100 ml, free T4 1.6 ng per 100 ml), suppression of the RAI uptake from 68% to 35%, and marked blunting of the responses

  7. Effect of hypothyroidism on female reproductive hormones

    PubMed Central

    Saran, Sanjay; Gupta, Bharti Sona; Philip, Rajeev; Singh, Kumar Sanjeev; Bende, Sureshrao Anoop; Agroiya, Puspalata; Agrawal, Pankaj

    2016-01-01

    Objective: Objective was to evaluate reproductive hormones levels in hypothyroid women and impact of treatment on their levels. Materials and Methods: A total of 59 women with untreated primary hypothyroidism were included in this prospective study. Venous blood was taken at baseline and after euthyroidism was achieved for measuring serum free thyroxine, free triiodothyronine (FT3), thyroid stimulating hormone (TSH), prolactin (PRL), follicular stimulating hormone (FSH), luteinizing hormone (LH), estradiol (E2), testosterone (T), and thyroid peroxidase antibody. Thirty-nine healthy women with regular menstrual cycles without any hormonal disturbances served as controls. The statistical analysis was performed using the Statistical Package for the Social Sciences Version 20 ([SPSS] IBM Corporation, Armonk, NY, USA). P < 0.05 was considered statistically significant. Results: On an average at diagnosis cases have more serum TSH (mean [M] = 77.85; standard error [SE] = 11.72), PRL (M = 39.65; SE = 4.13) and less serum E2 (M = 50.00; SE = 2.25) and T (M = 35.40; SE = 2.31) than after achieving euthyroidism (M = 1.74; SE = 0.73), (M = 16.04; SE = 0.84), (M = 76.25; SE = 2.60), and (M = 40.29; SE = 2.27), respectively. This difference was statistically significant t (58) = 6.48, P <0.05; t (58) = 6.49, P < 0.05; t (58) = 12.47; P < 0.05; and t (58) = 2.04, P < 0.05; respectively. Although average serum FSH (M = 12.14; SE = 0.40) and LH (M = 5.89; SE = 0.27) were lower in cases at diagnosis than after achieving euthyroidism (M = 12.70; SE = 0.40), (M = 6.22; SE = 0.25), respectively, but these differences were statistically insignificant t (58) = 1.61, P = 0.11; t (58) = 1.11, P = 0.27, respectively. Conclusion: The study has demonstrated low E2 and T levels in hypothyroid women which were increased after achieving euthyroidism. Although average serum FSH and LH were increased in hypothyroid women after achieving euthyroidism but this difference was statistically

  8. Weaponization of a Hormone: Convergent Recruitment of Hyperglycemic Hormone into the Venom of Arthropod Predators.

    PubMed

    Undheim, Eivind A B; Grimm, Lena L; Low, Chek-Fong; Morgenstern, David; Herzig, Volker; Zobel-Thropp, Pamela; Pineda, Sandy Steffany; Habib, Rosaline; Dziemborowicz, Slawomir; Fry, Bryan G; Nicholson, Graham M; Binford, Greta J; Mobli, Mehdi; King, Glenn F

    2015-07-01

    Arthropod venoms consist primarily of peptide toxins that are injected into their prey with devastating consequences. Venom proteins are thought to be recruited from endogenous body proteins and mutated to yield neofunctionalized toxins with remarkable affinity for specific subtypes of ion channels and receptors. However, the evolutionary history of venom peptides remains poorly understood. Here we show that a neuropeptide hormone has been convergently recruited into the venom of spiders and centipedes and evolved into a highly stable toxin through divergent modification of the ancestral gene. High-resolution structures of representative hormone-derived toxins revealed they possess a unique structure and disulfide framework and that the key structural adaptation in weaponization of the ancestral hormone was loss of a C-terminal α helix, an adaptation that occurred independently in spiders and centipedes. Our results raise a new paradigm for toxin evolution and highlight the value of structural information in providing insight into protein evolution.

  9. Multiple Effects of Growth Hormone in the Body: Is it Really the Hormone for Growth?

    PubMed Central

    Devesa, Jesús; Almengló, Cristina; Devesa, Pablo

    2016-01-01

    In this review, we analyze the effects of growth hormone on a number of tissues and organs and its putative role in the longitudinal growth of an organism. We conclude that the hormone plays a very important role in maintaining the homogeneity of tissues and organs during the normal development of the human body or after an injury. Its effects on growth do not seem to take place during the fetal period or during the early infancy and are mediated by insulin-like growth factor I (IGF-I) during childhood and puberty. In turn, IGF-I transcription is dependent on an adequate GH secretion, and in many tissues, it occurs independent of GH. We propose that GH may be a prohormone, rather than a hormone, since in many tissues and organs, it is proteolytically cleaved in a tissue-specific manner giving origin to shorter GH forms whose activity is still unknown. PMID:27773998

  10. Differential action of glycoprotein hormones: significance in cancer progression.

    PubMed

    Govindaraj, Vijayakumar; Arya, Swathy V; Rao, A J

    2014-02-01

    Growth of multicellular organisms depends on maintenance of proper balance between proliferation and differentiation. Any disturbance in this balance in animal cells can lead to cancer. Experimental evidence is provided to conclude with special reference to the action of follicle-stimulating hormone (FSH) on Sertoli cells, and luteinizing hormone (LH) on Leydig cells that these hormones exert a differential action on their target cells, i.e., stimulate proliferation when the cells are in an undifferentiated state which is the situation with cancer cells and promote only functional parameters when the cell are fully differentiated. Hormones and growth factors play a key role in cell proliferation, differentiation, and apoptosis. There is a growing body of evidence that various tumors express some hormones at high levels as well as their cognate receptors indicating the possibility of a role in progression of cancer. Hormones such as LH, FSH, and thyroid-stimulating hormone have been reported to stimulate cell proliferation and act as tumor promoter in a variety of hormone-dependent cancers including gonads, lung, thyroid, uterus, breast, prostate, etc. This review summarizes evidence to conclude that these hormones are produced by some cancer tissues to promote their own growth. Also an attempt is made to explain the significance of the differential action of hormones in progression of cancer with special reference to prostate cancer.

  11. [Sex Specificity in Age-Related Thyroid Hormone Responsiveness].

    PubMed

    Suzuki, Satoru

    2016-01-01

    Similar to other systems, the endocrine system is affected by aging. Thyroid hormone, the action of which is affected by many factors, has been shown to be associated with longevity. The most useful marker for assessment of the thyroid hormone action is the TSH level. Although age and sex are believed to modify the pituitary set point or response to the free thyroid hormone concentration, the precise age- and sex-dependent responses to thyroid hormone have yet to be reported. In this lecture, molecular aspects of resistance to thyroid hormone are initially overviewed. After presentation of the evidence that the TSH-thyroid hormone axis is evolutionarily modified, and that negative feedback mechanisms may start to play roles in homeostatic regulation at the time of delivery, the rationale of age-dependent thyroid hormone resistance is introduced. To assess the age- and sex-dependent resistance to thyroid hormone, the index is provided by the formula based on the relationship between thyroid hormone and TSH levels. The index is calculated by the results of thyroid function tests obtained from the two individual clinical groups. From the results, there were negative relationships between the free T3 resistance index and age in males of both groups, while there were no apparent relationships in females. These findings indicate that there is a male-specific response to thyroid hormone with aging. Furthermore, the specific features of the response may not be affected by environmental factors such as the presence of disorders or medical treatments. PMID:27192800

  12. Calcemic Fraction-A: Biosynthetic Peptide Precursor of Parathyroid Hormone

    PubMed Central

    Cohn, David V.; Macgregor, Ronal R.; Chu, Luke L. H.; Kimmel, Joe R.; Hamilton, James W.

    1972-01-01

    Calcemic fraction-A (CF-A) is a biologically active, hypercalcemic and bone resorptive peptide, which was detected in, and isolated from, bovine parathyroid glands [Hamilton et al. (1971) Endocrinology 89, 1440-1447]. It has been further purified, and its relationship to parathyroid hormone clarified. The peptide is present in fresh glands at a concentration of about 3 μg/g (parathyroid hormone, 100 μg/g). It contains 109 amino acids (hormone, 84), each of which is present in equal or greater molar ratio than in the hormone. Its molecular weight, calculated from amino-acid composition, is 12,144; determined by dodecyl sulfate-polyacrylamide gel electrophoresis, it is 12,500 (hormone, 9563). Per mole, it reacts with antiserum to parathyroid hormone to an extent of 7-10% that of the hormone, and is about 50% as active in its hypercalcemic and bone resorptive properties in the appropriate assays. Time course and pulse-chase experiments with parathyroid gland slices, in which the incorporation of amino acid into isolated peptide and hormone were measured, indicate that the hormone is made from a protein precursor; the patterns of incorporation of radioactivity are those that would be predicted from a precursor-product relationship. When the large peptide was incubated with parathyroid gland extracts it was partially converted to a molecule that appeared to be the hormone, as based upon its coelution with marker hormone from ion-exchange columns. Finally, tryptic digestion of the peptide increased the immunoreactivity of the sample in accord with the known greater immunoreactivity of the hormone than the peptide. On the basis of these results, it is proposed that the peptide is a biosynthetic precursor of the hormone in bovine parathyroid gland. PMID:4504366

  13. Relationship between urinary and serum growth hormone and pubertal status.

    PubMed Central

    Crowne, E C; Wallace, W H; Shalet, S M; Addison, G M; Price, D A

    1992-01-01

    Urinary growth hormone (uGH) excretion and serum growth hormone concentrations have been compared in three groups of children. Group 1 consisted of 21 children who had had cranial irradiation as part of their treatment for acute lymphoblastic leukaemia; group 2, 18 normal children; and group 3, 12 boys with constitutional delay in growth and puberty who were in early puberty. Children in groups 1 and 2 each had a 24 hour serum growth hormone profile (sampling every 20 minutes) and concurrent urine collection. The 12 boys in group 3 had a total of 21 profiles (sampling every 15 minutes for 12 hours) and concurrent urine collections. In the prepubertal children (n = 17), in both groups 1 and 2, there was a significant correlation between mean serum growth hormone and total uGHng/g creatinine. There were also significant correlations between total uGHng/g creatinine and both peak serum growth hormone and mean amplitude of the pulses in the growth hormone profile. In the pubertal children (n = 22), in groups 1 and 2, whether combined or in separate groups, there was no significant correlation between total uGHng/g creatinine and mean serum growth hormone, peak serum growth hormone, or mean amplitude of the pulses in the growth hormone profile. In group 3 there were significant correlations between total uGHng/g creatinine and both the mean serum growth hormone and mean amplitude of the pulses in the profile. Therefore uGH estimations appear to correlate well with serum growth hormone profiles in children who are prepubertal or in early puberty, but not in those further advanced in pubertal development. These results may reflect a variation in the renal handling of growth hormone during pubertal development. uGH estimation may be an unreliable screening investigation for growth hormone sufficiency in mid to late puberty. PMID:1739346

  14. Sex hormones, sex hormone binding globulin, and vertebral fractures in older men.

    PubMed

    Cawthon, Peggy M; Schousboe, John T; Harrison, Stephanie L; Ensrud, Kristine E; Black, Dennis; Cauley, Jane A; Cummings, Steven R; LeBlanc, Erin S; Laughlin, Gail A; Nielson, Carrie M; Broughton, Augusta; Kado, Deborah M; Hoffman, Andrew R; Jamal, Sophie A; Barrett-Connor, Elizabeth; Orwoll, Eric S

    2016-03-01

    The association between sex hormones and sex hormone binding globin (SHBG) with vertebral fractures in men is not well studied. In these analyses, we determined whether sex hormones and SHBG were associated with greater likelihood of vertebral fractures in a prospective cohort study of community dwelling older men. We included data from participants in MrOS who had been randomly selected for hormone measurement (N=1463, including 1054 with follow-up data 4.6years later). Major outcomes included prevalent vertebral fracture (semi-quantitative grade≥2, N=140, 9.6%) and new or worsening vertebral fracture (change in SQ grade≥1, N=55, 5.2%). Odds ratios per SD decrease in sex hormones and per SD increase in SHBG were estimated with logistic regression adjusted for potentially confounding factors, including age, bone mineral density, and other sex hormones. Higher SHBG was associated with a greater likelihood of prevalent vertebral fractures (OR: 1.38 per SD increase, 95% CI: 1.11, 1.72). Total estradiol analyzed as a continuous variable was not associated with prevalent vertebral fractures (OR per SD decrease: 0.86, 95% CI: 0.68 to 1.10). Men with total estradiol values ≤17pg/ml had a borderline higher likelihood of prevalent fracture than men with higher values (OR: 1.46, 95% CI: 0.99, 2.16). There was no association between total testosterone and prevalent fracture. In longitudinal analyses, SHBG (OR: 1.42 per SD increase, 95% CI: 1.03, 1.95) was associated with new or worsening vertebral fracture, but there was no association with total estradiol or total testosterone. In conclusion, higher SHBG (but not testosterone or estradiol) is an independent risk factor for vertebral fractures in older men. PMID:26778261

  15. Sex hormones, sex hormone binding globulin, and vertebral fractures in older men.

    PubMed

    Cawthon, Peggy M; Schousboe, John T; Harrison, Stephanie L; Ensrud, Kristine E; Black, Dennis; Cauley, Jane A; Cummings, Steven R; LeBlanc, Erin S; Laughlin, Gail A; Nielson, Carrie M; Broughton, Augusta; Kado, Deborah M; Hoffman, Andrew R; Jamal, Sophie A; Barrett-Connor, Elizabeth; Orwoll, Eric S

    2016-03-01

    The association between sex hormones and sex hormone binding globin (SHBG) with vertebral fractures in men is not well studied. In these analyses, we determined whether sex hormones and SHBG were associated with greater likelihood of vertebral fractures in a prospective cohort study of community dwelling older men. We included data from participants in MrOS who had been randomly selected for hormone measurement (N=1463, including 1054 with follow-up data 4.6years later). Major outcomes included prevalent vertebral fracture (semi-quantitative grade≥2, N=140, 9.6%) and new or worsening vertebral fracture (change in SQ grade≥1, N=55, 5.2%). Odds ratios per SD decrease in sex hormones and per SD increase in SHBG were estimated with logistic regression adjusted for potentially confounding factors, including age, bone mineral density, and other sex hormones. Higher SHBG was associated with a greater likelihood of prevalent vertebral fractures (OR: 1.38 per SD increase, 95% CI: 1.11, 1.72). Total estradiol analyzed as a continuous variable was not associated with prevalent vertebral fractures (OR per SD decrease: 0.86, 95% CI: 0.68 to 1.10). Men with total estradiol values ≤17pg/ml had a borderline higher likelihood of prevalent fracture than men with higher values (OR: 1.46, 95% CI: 0.99, 2.16). There was no association between total testosterone and prevalent fracture. In longitudinal analyses, SHBG (OR: 1.42 per SD increase, 95% CI: 1.03, 1.95) was associated with new or worsening vertebral fracture, but there was no association with total estradiol or total testosterone. In conclusion, higher SHBG (but not testosterone or estradiol) is an independent risk factor for vertebral fractures in older men.

  16. Role of sex-hormone-binding globulin and free sex steroid hormones in hyperandrogenic anovulation.

    PubMed

    Ohsawa, M; Asai, M; Masahashi, T; Narita, O; Tomoda, Y; Matsui, N

    1986-11-01

    To clarify the mechanism of hyperandrogenic anovulation, the binding capacity of sex-hormone-binding globulin (SHBG-BC), the levels of free steroid hormones, and the levels of basal serum testosterone (T), estradiol (E2), estrone (E1) and gonadotropins were determined in 42 hyperandrogenic anovulatory women. The mean levels of basal T (0.74 +/- 0.04 ng/ml, p less than 0.001), free T (3.07 +/- 0.51 ng/dl, p less than 0.01) and free E2 (2.26 +/- 0.27 pg/ml, p less than 0.05), basal luteinizing hormone (LH) (33.4 +/- 2.7 mIU/ml, p less than 0.001), responsiveness of LH (180.7 +/- 21.5 mIU/ml, p less than 0.001) after luteinizing hormone releasing hormone (LHRH) administration, and the basal LH/basal follicle stimulating hormone (FSH) ratio (3.42 +/- 0.25, p less than 0.001) in the patients were significantly higher, the SHBG-BC level (1.76 +/- 0.33 micrograms DHT bound/dl, p less than 0.05) significantly reduced, and basal levels of E2 (38.0 +/- 3.2 pg/ml) and E1 (110 +/- 13 pg/ml) unchanged compared to the controls. These findings suggest that increased T in hyperandrogenic anovulatory women results in decreased SHBG-BC and increased free T and E2 which might be the cause of inappropriate gonadotropin secretion followed by chronic anovulation. PMID:2947958

  17. A therapeutic response to a single diagnostic dose of luteinising hormone-releasing hormone.

    PubMed

    Distiller, L A; Sagel, J; Polakow, E S; Morley, J E

    1975-01-11

    Luteinising hormone-releasing hormone (LH-RH) administration is a useful provocative test for the evaluation of the hypothalamic-pituitary-gonadal axis. Seven cases with oligomenorrhoea or amenorrhoea are reported, in which a single diagnostic injection of LH-RH produced an apparent therapeutic response. Six patients converted to a regular normal menstrual cycle, and 4 of these had evidence of ovulation. The seventh patient conceived. It is postulated that in some cases of hypothalamic menstrual dysfunction the gonadotrophic imbalance may be corrected by a single intravenous dose of LH-RH.

  18. An improved thyroid hormone reporter assay to determine the thyroid hormone-like activity of amiodarone, bithionol, closantel and rafoxanide.

    PubMed

    Matsubara, Kana; Sanoh, Seigo; Ohta, Shigeru; Kitamura, Shigeyuki; Sugihara, Kazumi; Fujimoto, Nariaki

    2012-01-01

    A number of environmental chemicals have been reported to exhibit thyroid hormone-like activity. Since thyroid hormones play a crucial role in development, it is important to identify chemicals in the environment that are capable of endocrine disruption of thyroid hormone homeostasis. In order to detect thyroid hormone-like activity, the growth of pituitary cell lines has been commonly used as a sensitive marker, albeit with limited specificity to thyroid hormones. Reporter gene assays using the thyroid hormone responsive element (TRE) connected to the luciferase reporter gene have also been developed. Thus far however, this type of assay appears to have limited sensitivity compared to cell growth assays. In the present study, we developed a highly sensitive TRE reporter gene assay by using a pituitary cell line, MtT/E-2, and by culturing cells in a serum-free medium. Our assay was developed in order to detect T3 activity at a concentration of 10(-11)M. This assay identified thyroid hormone-like activity from the antiarrhythmic drug, amiodarone, and from three anti-parasitic drugs, bithionol, closantel and rafoxanide, all commonly used in veterinary medicine. Thyroid hormone-like activity of these compounds was further confirmed by the induction of BCL3 gene expression in MtT/E-2, which is known to be regulated by thyroid hormones. Our improved assay was proved to be a sensitive tool for assessing thyroid hormone-like activity of environmental chemicals. PMID:22015988

  19. Transport of thyroid hormones via the choroid plexus into the brain: the roles of transthyretin and thyroid hormone transmembrane transporters.

    PubMed

    Richardson, Samantha J; Wijayagunaratne, Roshen C; D'Souza, Damian G; Darras, Veerle M; Van Herck, Stijn L J

    2015-01-01

    Thyroid hormones are key players in regulating brain development. Thus, transfer of appropriate quantities of thyroid hormones from the blood into the brain at specific stages of development is critical. The choroid plexus forms the blood-cerebrospinal fluid barrier. In reptiles, birds and mammals, the main protein synthesized and secreted by the choroid plexus is a thyroid hormone distributor protein: transthyretin. This transthyretin is secreted into the cerebrospinal fluid and moves thyroid hormones from the blood into the cerebrospinal fluid. Maximal transthyretin synthesis in the choroid plexus occurs just prior to the period of rapid brain growth, suggesting that choroid plexus-derived transthyretin moves thyroid hormones from blood into cerebrospinal fluid just prior to when thyroid hormones are required for rapid brain growth. The structure of transthyretin has been highly conserved, implying strong selection pressure and an important function. In mammals, transthyretin binds T4 (precursor form of thyroid hormone) with higher affinity than T3 (active form of thyroid hormone). In all other vertebrates, transthyretin binds T3 with higher affinity than T4. As mammals are the exception, we should not base our thinking about the role of transthyretin in the choroid plexus solely on mammalian data. Thyroid hormone transmembrane transporters are involved in moving thyroid hormones into and out of cells and have been identified in many tissues, including the choroid plexus. Thyroid hormones enter the choroid plexus via thyroid hormone transmembrane transporters and leave the choroid plexus to enter the cerebrospinal fluid via either thyroid hormone transmembrane transporters or via choroid plexus-derived transthyretin secreted into the cerebrospinal fluid. The quantitative contribution of each route during development remains to be elucidated. This is part of a review series on ontogeny and phylogeny of brain barrier mechanisms.

  20. Hormone balance and abiotic stress tolerance in crop plants.

    PubMed

    Peleg, Zvi; Blumwald, Eduardo

    2011-06-01

    Plant hormones play central roles in the ability of plants to adapt to changing environments, by mediating growth, development, nutrient allocation, and source/sink transitions. Although ABA is the most studied stress-responsive hormone, the role of cytokinins, brassinosteroids, and auxins during environmental stress is emerging. Recent evidence indicated that plant hormones are involved in multiple processes. Cross-talk between the different plant hormones results in synergetic or antagonic interactions that play crucial roles in response of plants to abiotic stress. The characterization of the molecular mechanisms regulating hormone synthesis, signaling, and action are facilitating the modification of hormone biosynthetic pathways for the generation of transgenic crop plants with enhanced abiotic stress tolerance.

  1. Can Bayliss and Starling gut hormones cure a worldwide pandemic?

    PubMed

    Scott, R V; Tan, T M; Bloom, S R

    2014-12-01

    Bayliss and Starling first coined the term 'hormone' with reference to secretin, a substance they found that was produced by the gut, but released into the blood stream to act at a distance. The intestine is now known as the largest endocrine organ in the body, and it produces numerous hormones with a wide range of functions. These include controlling appetite and energy homeostasis. Obesity is one of the greatest health threats facing the world today. At present, the only successful treatment is surgery. Bariatric procedures such as the Roux-en-Y bypass work by elevating gut hormones that induce satiety. Significant research has gone into producing versions of these hormones that can be delivered therapeutically to treat obesity. This review looks at the role of gut hormones in obesity, and the development of gut hormone-derived obesity treatments. PMID:25217372

  2. The replacement of serum by hormones in cell culture media.

    PubMed

    Sato, G; Hayashi, I

    1976-12-01

    The replacement of serum by hormones in cell culture media. (Reemplazo del suero por hormonas en el medio de cultivo de células). Arch. Biol. Med. Exper. 10: 120-121, 1976. The serum used in cell culture media can be replaced by a mixture of hormones and some accesory blood factors. The pituitary cell line GH3 can be grown in a medium in which serum is replaced by triiodothyronine, transferrin, parathormone, tyrotrophin releasing hormone and somatomedins. Hela and BHK cell strains can also be grown in serum free medium supplemented with hormones. Each cell type appears to have different hormonal requirements yet it may found that some hormones are required for most cell types.

  3. Studies on the nature of plasma growth hormone

    NASA Technical Reports Server (NTRS)

    Ellis, S.; Grindeland, R. E.; Reilly, T. J.; Yang, S. H.

    1976-01-01

    The paper presents further evidence for the existence of two discrete forms of growth hormone in human plasma, one which is detectable by both radioimmunoassay and bioassay and is immunoreactive, and the other, termed 'bioactive', which is detected by tibial bioassay but shows little reactivity with currently available antisera to pituitary growth hormone. The same division of immunoactive and bioactive growth hormone occurs in rats, though with less disparity. Tests on rats indicated that the bioactive hormone is preferentially released into jugular vein plasma and that plasma concentrations of the bioactive hormone can be enhanced by insulin administration. The bioactive hormone was detectable by tibial assays in Cohn fractions IV, IV-1, and IV-4, and could be concentrated about 40-fold by fractionation with (NaPO3)6 and (NH4)2SO4.

  4. Genetics and epigenetics of parathyroid hormone resistance.

    PubMed

    Bastepe, Murat

    2013-01-01

    End-organ resistance to the actions of parathyroid hormone (PTH) is defined as pseudohypoparathyroidism (PHP). Described originally by Fuller Albright and his colleagues in early 1940s, this rare genetic disease is subclassified into two types according to the nephrogenous response to the administration of biologically active PTH. In type I, the PTH-induced urinary excretion of both phosphate and cyclic AMP (cAMP) is blunted. In type II, only the PTH-induced urinary excretion of phosphate is blunted, while the cAMP response is unimpaired. Different subtypes of PHP type I have been described based on the existence of additional clinical features, such as resistance to other hormones and Albright's hereditary osteodystrophy, and underlying molecular defects. Genetic mutations responsible for the different subtypes of PHP type I involve the GNAS complex locus, an imprinted gene encoding the α-subunit of the stimulatory G protein (Gsα) and several other transcripts that are expressed in a parent-of-origin specific manner. Mutations in Gsα-coding GNAS exons cause PHP-Ia and, in some cases, PHP-Ic, while mutations that disrupt the imprinting of GNAS lead to PHP-Ib. PHP type II is less well characterized with respect to its molecular cause. Recently, however, mutations in PRKAR1A, a regulatory subunit of the cAMP-dependent protein kinase, have been identified in several cases of PTH and other hormone resistance and skeletal dysplasia that are considered to be affected by PHP type II due to unimpaired urinary excretion of cAMP following PTH administration.

  5. Genetics and epigenetics of parathyroid hormone resistance.

    PubMed

    Bastepe, Murat

    2013-01-01

    End-organ resistance to the actions of parathyroid hormone (PTH) is defined as pseudohypoparathyroidism (PHP). Described originally by Fuller Albright and his colleagues in early 1940s, this rare genetic disease is subclassified into two types according to the nephrogenous response to the administration of biologically active PTH. In type I, the PTH-induced urinary excretion of both phosphate and cyclic AMP (cAMP) is blunted. In type II, only the PTH-induced urinary excretion of phosphate is blunted, while the cAMP response is unimpaired. Different subtypes of PHP type I have been described based on the existence of additional clinical features, such as resistance to other hormones and Albright's hereditary osteodystrophy, and underlying molecular defects. Genetic mutations responsible for the different subtypes of PHP type I involve the GNAS complex locus, an imprinted gene encoding the α-subunit of the stimulatory G protein (Gsα) and several other transcripts that are expressed in a parent-of-origin specific manner. Mutations in Gsα-coding GNAS exons cause PHP-Ia and, in some cases, PHP-Ic, while mutations that disrupt the imprinting of GNAS lead to PHP-Ib. PHP type II is less well characterized with respect to its molecular cause. Recently, however, mutations in PRKAR1A, a regulatory subunit of the cAMP-dependent protein kinase, have been identified in several cases of PTH and other hormone resistance and skeletal dysplasia that are considered to be affected by PHP type II due to unimpaired urinary excretion of cAMP following PTH administration. PMID:23392091

  6. Hormonal contraception. Current status and future perspectives.

    PubMed

    Holinka, C F

    1994-09-30

    Hormonal contraception was pioneered by Gregory Pincus in the 1950s. Today, hormonal contraception is accepted as having a highly favorable benefit/risk profile. There is, however, a need for the development of new contraceptive methods to broaden the range of choices and enhance motivation and compliance in users. With the staggering rate of increase in the world's population, the number of contraceptive users in developing countries is expected to increase from 381 million in 1990 to 567 million in the year 2000. This will require substantial supplies of inexpensive contraceptives and the development of new and improved methods. The use of contraceptives is an asset to women's health, which can be jeopardized by the risks of pregnancy, as well as to the psychological and social well-being of mother and child. Oral contraceptives also have noncontraceptive health benefits such as protecting against endometrial cancer, uterine fibroids, menorrhagia, benign breast disease, anemia, ovarian cancer, functional ovarian cysts, dysmenorrhea, ectopic pregnancy, salpingitis, and bone loss. The new low-dose formulations are considered to be very safe for most healthy, nonsmoking women of reproductive age. Therefore, current research efforts are focused on new delivery methods, such as vaginal rings, rather than on the development of new hormonally active steroids. Nonoral contraceptive methods which avoid first-pass effects on the liver are being developed or improved. These include implants, vaginal rings, vaginally applied pills, and progestogen-containing IUDs. Contraceptive research is also focusing on immunologic interference with the hypothalamic-pituitary-gonadal axis in both men and women. This may spawn as yet unforseen methods of molecular modulation of sperm-ovum interactions which would result in the inhibition of implantation.

  7. THE INTRACELLULAR LOCALIZATION OF PITUITARY THYROTROPIC HORMONE

    PubMed Central

    Greenspan, Francis S.; Hargadine, Judy R.

    1965-01-01

    The intracellular localization of a bovine anterior pituitary preparation of thyroid-stimulating hormone (TSH) was studied in guinea pigs and dogs. The preparation was administered intravascularly or applied directly to tissue sections. TSH was detected by an indirect technique utilizing bovine TSH antiserum and fluorescein-labeled anti-rabbit globulin; the presence of TSH in the tissue was indicated by fluorescence when the tissue was examined under the microscope with an ultraviolet light source. After either intravascular administration or direct application of the TSH preparation, striking fluorescence was found in the nuclei of the thyroid cells and to a lesser degree in the nuclei of retro-orbital fat tissue and kidney tubules in both species studied. A little fluorescence was also seen in spleen tissue. No fluorescence was noted in comparable tissues removed from control animals injected with bovine albumin or globulin or when the tissues were treated with the fluorescein-labeled globulin alone. Fluorescence was also noted in the nuclei of adrenal cells treated with unabsorbed antiserum, but this was greatly diminished when antiserum absorbed with crystalline ACTH was used. The positive reactions were all markedly decreased when the tissues were treated with antisera absorbed with the original TSH preparation. Fluorescence was noted in the cytoplasm of pituitary tissue from both treated and control animals, suggesting a cross-reaction between the bovine pituitary antisera and guinea pig or dog hypophysis. The indirect technique seems to be highly satisfactory for demonstration of the pitiutary hormone within the cell. In addition, the demonstration of immunologically active anterior pituitary TSH bound to cell nuclei offers a clue to the site of action of this hormone. PMID:5323607

  8. Hormonal and metabolic evaluation of adrenal incidentalomas.

    PubMed

    Wagnerova, H; Dudasova, D; Lazurova, I

    2009-01-01

    The biochemical and hormonal data in patients with adrenal incidentalomas were evaluated to compare the differences between adrenal adenomas and other benign lesions and to find the relationship between metabolic parameters and adrenal hormones. Ninety two patients (29men, age 20-90 years) with incidentally discovered unilateral or bilateral adrenal masses detected on CT were included in this study for the reasons others than adrenal pathology. Glycemia, cholesterolemia, triglyceridemia, hormonal evaluation including plasma ACTH, plasma aldosterone, plasma renin acitivity, overnight dexametasone test, ACTH test, free plasma metanephrines, urinary catecholamines were determined. In the group of patients with adrenal masses the prevalence of arterial hypertension was three fold higher, the prevalence of DM was approximately five fold higher and the prevalence of the overweight and obesity two fold higher than is reported in the general population. The most frequent adrenal masses were nonfunctional masses, the occurence of functional lesions was as follows: steroid enzymopathies (an exaggerated response of 17-OHP indicating a possible 21-hydroxylase deficiency), subclinical Cushing syndrome, primary aldosteronism and pheochromocytoma (5%, 2%, 2% and 1% respectively). There were no significant differences in evaluated data between patients with adenomas and hyperplasia and also no significant difference in evaluated data between lesions smaller than 3 cm and lesions greater than 3 cm. We did not find any correlations between plasma cortisol and lipid values. In this study we confirmed a higher prevalence of symptoms characteristic for different metabolic syndromes in these patients with adrenal incidentalomas, which indicate systematic screening for the metabolic syndrome including evaluation of the insuline resistance in this patients. PMID:19728761

  9. Postmenopausal Hormone Therapy and Risk of Stroke

    PubMed Central

    Carcaillon, Laure; Plu-Bureau, Geneviève; Oger, Emmanuel; Singh-Manoux, Archana; Tubert-Bitter, Pascale; Elbaz, Alexis; Scarabin, Pierre-Yves

    2016-01-01

    Background and Purpose— The benefit/risk analysis of hormone therapy in postmenopausal women is not straightforward and depends on cardiovascular disease. Evidence supports the safety of transdermal estrogens and the importance of progestogens for thrombotic risk. However, the differential association of oral and transdermal estrogens with stroke remains poorly investigated. Furthermore, there are no data regarding the impact of progestogens. Methods— We set up a nested case–control study of ischemic stroke (IS) within all French women aged 51 to 62 years between 2009 and 2011 without personal history of cardiovascular disease or contraindication to hormone therapy. Participants were identified using the French National Health Insurance database, which includes complete drug claims for the past 3 years and French National hospital data. We identified 3144 hospitalized IS cases who were matched for age and zip code to 12 158 controls. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Results— Compared with nonusers, the adjusted ORs of IS were1.58 (95% CI, 1.01–2.49) in oral estrogen users and 0.83 (0.56–1.24) in transdermal estrogens users (P<0.01). There was no association of IS with use of progesterone (OR, 0.78; 95% CI, 0.49–1.26), pregnanes (OR, 1.00; 95% CI, 0.60–1.67), and nortestosterones (OR, 1.26; 95% CI, 0.62–2.58), whereas norpregnanes increased IS risk (OR, 2.25; 95% CI, 1.05–4.81). Conclusions— Both route of estrogen administration and progestogens were important determinants of IS. Our findings suggest that transdermal estrogens might be the safest option for short-term hormone therapy use. PMID:27256671

  10. Hormonal regulation of hepatocyte tight junctional permeability

    SciTech Connect

    Lowe, P.J.; Miyai, K.; Steinbach, J.H.; Hardison, W.G.M. Univ. of California, San Diego )

    1988-10-01

    The authors have investigated the effects of hormones on the permeability of the hepatocyte tight junction to two probes, ({sup 14}C)sucrose and horseradish peroxidase, using one-pass perfused rat livers. Using a single injection of horseradish peroxidase the authors have demonstrated that this probe can enter bile by two pathways that are kinetically distinct, a fast pathway, which corresponds to the passage of the probe through the hepatocyte tight junctions, and a slow pathway, which corresponds to the transcytotic entry into bile. The passage of horseradish peroxidase through the hepatocyte tight junctions was confirmed by electron microscopic histochemistry. Vasopressin, epinephrine, and angiotensin II, hormones that act in the hepatocyte through the intracellular mediators calcium, the inositol polyphosphates, and diacylglycerol, increased the bile-to-perfusion fluid ratio of ({sup 14}C)sucrose and the rapid entry of horseradish peroxidase into bile, indicating that the permeability of the tight junctions to these probes was increased. The effect of these hormones was dose dependent and in the cases of angiotensin II and epinephrine was inhibited by the specific inhibitors (Sar{sup 1},Thr{sup 8})angiotensin II and prazosin, respectively. Dibutyryl adenosine 3{prime},5{prime}-cyclic monophosphate did not affect the ({sup 14}C)sucrose bile-to-perfusion fluid ratio or the fast entry of horseradish peroxidase into bile. These results suggest that the hepatocyte tight junction can no longer be considered a static system of pores separating blood from bile. It is rather a dynamic barrier potentially capable of influencing the composition of the bile.

  11. Growth hormone therapy in children with chronic renal failure.

    PubMed

    Cayir, Atilla; Kosan, Celalettin

    2015-02-01

    Growth is impaired in a chronic renal failure. Anemia, acidosis, reduced intake of calories and protein, decreased synthesis of vitamin D and increased parathyroid hormone levels, hyperphosphatemia, renal osteodystrophy and changes in growth hormone-insulin-like growth factor and the gonadotropin-gonadal axis are implicated in this study. Growth is adversely affected by immunosuppressives and corticosteroids after kidney transplantation. Treating metabolic disorders using the recombinant human growth hormone is an effective option for patients with inadequate growth rates. PMID:25745347

  12. Hormone supply of the organism in prolonged emotional stress

    NASA Technical Reports Server (NTRS)

    Amiragova, M. G.; Stulnikov, B. V.; Svirskaya, R. I.

    1980-01-01

    The effect of prolonged emotional stress of varying genesis on the hormonal function of the pancreas, thyroid gland, and adrenal cortex was studied. The amount of the hormonal secretion was found to depend on the type of adaptation activity and its duration. High secretion of the hormones observed outside the adaptation activity was examined as an index of the phase transition of defense reactions to the phase of overstress.

  13. Steroid plant hormones: effects outside plant kingdom.

    PubMed

    Zhabinskii, Vladimir N; Khripach, Natalia B; Khripach, Vladimir A

    2015-05-01

    Brassinosteroids (BS) are the first group of steroid-hormonal compounds isolated from and acting in plants. Among numerous physiological effects of BS growth stimulation and adaptogenic activities are especially remarkable. In this review, we provide evidence that BS possess similar types of activity also beyond plant kingdom at concentrations comparable with those for plants. This finding allows looking at steroids from a new point of view: how common are the mechanisms of steroid bioregulation in different types of organisms from protozoa to higher animals.

  14. Hormonal contraceptives and travel to high altitude.

    PubMed

    Keyes, Linda E

    2015-03-01

    Women frequently ask about the safety and efficacy of using hormonal contraception (HC), either oral contraceptive pills (OC) or other forms, when traveling to high altitude locales. What are the risks and benefits of using HC at high altitude? Does HC affect acclimatization, exercise performance, or occurrence of acute mountain sickness? This article reviews current data regarding the risks and benefits of HC at high altitude, both demonstrated and theoretical, with the aim of helping health care providers to advise women traveling above 2500 meters. Most healthy women can safely use HC when traveling to high altitude, but should be aware of the potential risks and inconveniences.

  15. [Pathologic manifestations of hormonal receptor mutations].

    PubMed

    Milgrom, E

    2000-01-01

    Mutations of receptor genes are involved in various aspects of thyroid and gonadal pathology. Activating mutations of TSH and LH receptors are associated with hyperthyroidism and premature puberty. These mutations are dominant and lead to the synthesis of a constitutive receptor, i.e. a receptor active even in the absence of hormone. Inactivating mutations of TSH, gonadotropin and GnRH receptors are recessive. They determine either a hypothyroidism or a hypogonadism. In the case of alterations of gonadotropin receptors the hypogonadism is hypergonadotrophic. It is hypogonadotrophic in the case of mutations of the GnRH receptor. PMID:10989556

  16. Reproductive Hormones and the Menopause Transition

    PubMed Central

    Santoro, Nanette; Randolph, John F

    2011-01-01

    The hormonal correlates of reproductive aging and the menopause transition reflect an initial loss of the follicle cohort, while a responsive ovary remains, and an eventual complete loss of follicle response, with persistent hypergonadotropic amenorrhea. The physiology of the process is described, along with key findings of relevant studies, with an emphasis on SWAN, the Study of Women’s Health Across the Nation. A clinical framework is provided to help clinicians forecast the major milestones of the menopausal transition and to predict potential symptoms or disease. PMID:21961713

  17. Alien environments and the hormone of love.

    PubMed

    Wickham, Sara

    2015-02-01

    Recent research collaboration between NASA and other agencies has led to the publication of a series of papers reviewing our knowledge about the impact of sex and gender on adaptation to Space. In this article, I look at some of the findings of the review on reproductive health, which considers the effects of radiation, microgravity and stress. The results show that, among other things, Space flight can have a significant effect on the hormones of astronauts and,cosmonauts, and I raise questions about the difference in approach taken in different fields and about how we evaluate the effects of different--and sometimes alien--environments on our health and wellbeing.

  18. Experience with hormone receptors in renal cancer.

    PubMed

    Romics, I; Rüssel, C; Bach, D

    1990-01-01

    The hormone receptor concentrations in tumour tissues from 20 renal carcinoma patients were determined before postoperative medroxyprogesterone acetate (MPA) therapy was started. Except for glucocorticoid receptors, the concentrations were either not measurable or were extremely low. The question is whether MPA therapy, solely on the strength of its character as a general roborant, is still useful in the treatment of renal tumours, even when it fails to exercise primary influence because of the absence of suitable receptors. None of the 20 patients was treated with MPA.

  19. [Changes in calcium regulating hormone in osteoporosis].

    PubMed

    Okamoto, Y; Ota, K

    1994-09-01

    We summarized the changes of humoral factors, vitamin D, parathyroid hormone, and calcitonin in blood concentration, which are cooperatively regulating calcium homeostasis in aging and osteoporosis. Although these factors may play a important role on pathogenesis of osteoporosis in aged and postmenopausal osteoporotic patients, the influence of these factors on the mechanism of age-related or postmenopausal bone loss is unclear. There is no characteristic change of these factors in blood because of heterogeneity of osteoporosis and it is controversial. Further studies are required to evaluate the state of osteoporosis. PMID:7967071

  20. Random Secretion of Growth Hormone in Humans

    NASA Astrophysics Data System (ADS)

    Prank, Klaus; Kloppstech, Mirko; Nowlan, Steven J.; Sejnowski, Terrence J.; Brabant, Georg

    1996-08-01

    In normal humans, growth hormone (GH) is secreted from a gland located adjacent to the brain (pituitary) into the blood in distinct pulses, but in patients bearing a tumor within the pituitary (acromegaly) GH is excessively secreted in an irregular manner. It has been hypothesized that GH secretion in the diseased state becomes random. This hypothesis is supported by demonstrating that GH secretion in patients with acromegaly cannot be distinguished from a variety of linear stochastic processes based on the predictability of the fluctuations of GH concentration in the bloodstream.

  1. Hormone purification by isoelectric focusing in space

    NASA Technical Reports Server (NTRS)

    Bier, M.

    1982-01-01

    The performance of a ground-prototype of an apparatus for recycling isoelectric focusing was evaluated in an effort to provide technology for large scale purification of peptide hormones, proteins, and other biologicals. Special emphasis was given to the effects of gravity on the function of the apparatus and to the determination of potential advantages deriveable from its use in a microgravity environment. A theoretical model of isoelectric focusing sing chemically defined buffer systems for the establishment of the pH gradients was developed. The model was transformed to a form suitable for computer simulations and was used extensively for the design of experimental buffers.

  2. Hormonal contraceptives and travel to high altitude.

    PubMed

    Keyes, Linda E

    2015-03-01

    Women frequently ask about the safety and efficacy of using hormonal contraception (HC), either oral contraceptive pills (OC) or other forms, when traveling to high altitude locales. What are the risks and benefits of using HC at high altitude? Does HC affect acclimatization, exercise performance, or occurrence of acute mountain sickness? This article reviews current data regarding the risks and benefits of HC at high altitude, both demonstrated and theoretical, with the aim of helping health care providers to advise women traveling above 2500 meters. Most healthy women can safely use HC when traveling to high altitude, but should be aware of the potential risks and inconveniences. PMID:25759908

  3. Responses of ram lambs to active immunization against testosterone and luteinizing hormone-releasing hormone.

    PubMed

    Schanbacher, B D

    1982-03-01

    Active immunization of young ram lambs against testosterone and luteinizing hormone-releasing hormone (LHRH) was shown to block the growth attributes characteristic of intact ram lambs. Testosterone and LHRH-immunized lambs grew at a slower rate and converted feed to live weight gain less efficiently than albumin-immunized controls. Lambs immunized against testosterone and LHRH had high antibody titers for their respective antigens. Moreover, testosterone-immunized lambs had high serum concentrations of luteinizing hormone (LH) and testosterone, whereas LHRH-immunized lambs had low to nondetectable serum concentrations of these hormones. Release of LH and testosterone following the intravenous administration of LHRH (250 ng) was absent in LHRH-immunized lambs, but quantitatively similar for intact and albumin-immunized control lambs. Testosterone-immunized lambs responded as did conventional castrates with a large LH release, but testosterone concentrations were unchanged. These findings are discussed relative to the integrity of the hypothalamic-pituitary-testicular endocrine axis and the importance of gonadotropin support for normal testicular development. These data show that LHRH immunoneutralization effectively retards testicular development and produces a castration effect in young ram lambs.

  4. Central administration of chicken growth hormone-releasing hormone decreases food intake in chicks.

    PubMed

    Tachibana, Tetsuya; Sugimoto, Ikue; Ogino, Madoka; Khan, Md Sakirul Islam; Masuda, Keiko; Ukena, Kazuyoshi; Wang, Yajun

    2015-02-01

    Growth hormone-releasing hormone (GHRH) is well known as a stimulator of growth hormone (GH) secretion. GHRH not only stimulates GH release but also modifies feeding behavior and energy homeostasis in rodents. In chickens (Gallus gallus domesticus), on the other hand, two types of GHRH, namely, chicken GHRH (cGHRH) and cGHRH-like peptide (cGHRH-LP), have been identified. The purpose of the present study was to investigate the effect of central injection of cGHRH and cGHRH-LP on feeding behavior in chicks. Intracerebroventricular (ICV) injection of both cGHRH and cGHRH-LP (0.04 to 1 nmol) significantly decreased food intake without any abnormal behavior in chicks. Furthermore, the feeding-inhibitory effect was not abolished by co-injection of the antagonist for pituitary adenylate cyclase-activating polypeptide (PACAP) or corticotropin-releasing hormone (CRH) receptors, suggesting that the anorexigenic effect of cGHRH and cGHRH-LP might not be related to the PACAP and CRH systems in the brain of chicks. Finally, 24-h food deprivation increased mRNA expression of cGHRH but not cGHRH-LP in the diencephalon. These results suggest that central cGHRH is related to inhibiting feeding behavior and energy homeostasis in chicks.

  5. THYROID HORMONE INSUFFICIENCY AND BRAIN DEVELOPMENT -- DETERMINATION OF NEUROTOXICITY AT LOW LEVELS OF HORMONE DISRUPTION.

    EPA Science Inventory

    Thyroid hormone (TH) deficiencies during development produce deleterious effects on brain structure and function. The degree to which TH must be perturbed to induce neurotoxicity remains unclear. The present study was conducted as part of a Cooperative Agreement between US EPA, U...

  6. Enzyme action in the regulation of plant hormone responses.

    PubMed

    Westfall, Corey S; Muehler, Ashley M; Jez, Joseph M

    2013-07-01

    Plants synthesize a chemically diverse range of hormones that regulate growth, development, and responses to environmental stresses. The major classes of plant hormones are specialized metabolites with exquisitely tailored perception and signaling systems, but equally important are the enzymes that control the dose and exposure to the bioactive forms of these molecules. Here, we review new insights into the role of enzyme families, including the SABATH methyltransferases, the methylesterases, the GH3 acyl acid-amido synthetases, and the hormone peptidyl hydrolases, in controlling the biosynthesis and modifications of plant hormones and how these enzymes contribute to the network of chemical signals responsible for plant growth, development, and environmental adaptation.

  7. Borjeson-Forssman-Lehmann syndrome and multiple pituitary hormone deficiency.

    PubMed

    Birrell, G; Lampe, A; Richmond, S; Bruce, S N; Gécz, J; Lower, K; Wright, M; Cheetham, T D

    2003-12-01

    We describe two brothers with Borjeson-Forssman-Lehmann syndrome and the 22A-->T (Lys8X) PHF6 mutation, who presented with the symptoms and signs of multiple pituitary hormone deficiency. Biochemical investigations and radiology confirmed growth hormone (GH), thyroid stimulating hormone (TSH) and adrenocorticotrophic hormone (ACTH) as well as gonadotrophin deficiency. They were also found to have optic nerve hypoplasia. This family suggests that the BFL gene product may play an important role in midline neuro-development including the hypothalamo-pituitary axis.

  8. Clinical implications of thyroid hormones effects on nervous system development.

    PubMed

    Carreón-Rodríguez, Alfonso; Pérez-Martínez, Leonor

    2012-03-01

    Thyroid hormones have an important role throughout prenatal and postnatal nervous system development. They are involved in several processes such as neurogenesis, gliogenesis, myelination, synaptogenesis, etc., as shown in many cases of deficiency like congenital hypothyroidism or hypothyroxinemia. Those pathologies if untreated could lead to severe damages in cognitive, motor, neudoendocrine functions among other effects. Some could be reversed after adequate supplementation of thyroid hormones at birth, however there are other cellular processes highly sensitive to low levels of thyroid hormones and lasting a limited period of time during which if thyroid hormone action is lacking or deficient, the functional and structural damages would produce permanent defects. PMID:22523832

  9. The effects of hormonal contraceptives on glycemic regulation

    PubMed Central

    Cortés, Manuel E.; Alfaro, Andrea A.

    2014-01-01

    A number of side effects have been linked to the use of hormonal contraceptives, among others, alterations in glucose levels. Hence, the objective of this mini-review is to show the main effects of hormonal contraceptive intake on glycemic regulation. First, the most relevant studies on this topic are described, then the mechanisms that might be accountable for this glycemic regulation impairment as exerted by hormonal contraceptives are discussed. Finally, we briefly discuss the ethical responsibility of health professionals to inform about the potential risks on glycemic homeostasis regarding hormonal contraceptive intake. PMID:25249703

  10. The growth hormone receptor: mechanism of activation and clinical implications.

    PubMed

    Brooks, Andrew J; Waters, Michael J

    2010-09-01

    Growth hormone is widely used clinically to promote growth and anabolism and for other purposes. Its actions are mediated via the growth hormone receptor, both directly by tyrosine kinase activation and indirectly by induction of insulin-like growth factor 1 (IGF-1). Insensitivity to growth hormone (Laron syndrome) can result from mutations in the growth hormone receptor and can be treated with IGF-1. This treatment is, however, not fully effective owing to the loss of the direct actions of growth hormone and altered availability of exogenous IGF-1. Excessive activation of the growth hormone receptor by circulating growth hormone results in gigantism and acromegaly, whereas cell transformation and cancer can occur in response to autocrine activation of the receptor. Advances in understanding the mechanism of receptor activation have led to a model in which the growth hormone receptor exists as a constitutive dimer. Binding of the hormone realigns the subunits by rotation and closer apposition, resulting in juxtaposition of the catalytic domains of the associated tyrosine-protein kinase JAK2 below the cell membrane. This change results in activation of JAK2 by transphosphorylation, then phosphorylation of receptor tyrosines in the cytoplasmic domain, which enables binding of adaptor proteins, as well as direct phosphorylation of target proteins. This model is discussed in the light of salient information from closely related class 1 cytokine receptors, such as the erythropoietin, prolactin and thrombopoietin receptors. PMID:20664532

  11. Socially selected ornaments influence hormone titers of signalers and receivers.

    PubMed

    Tibbetts, Elizabeth A; Crocker, Katherine; Huang, Zachary Y

    2016-07-26

    Decades of behavioral endocrinology research have shown that hormones and behavior have a bidirectional relationship; hormones both influence and respond to social behavior. In contrast, hormones are often thought to have a unidirectional relationship with ornaments. Hormones influence ornament development, but little empirical work has tested how ornaments influence hormones throughout life. Here, we experimentally alter a visual signal of fighting ability in Polistes dominulus paper wasps and measure the behavioral and hormonal consequences of signal alteration in signalers and receivers. We find wasps that signal inaccurately high fighting ability receive more aggression than controls and receiving aggression reduces juvenile hormone (JH) titers. As a result, immediately after contests, inaccurate signalers have lower JH titers than controls. Ornaments also directly influence rival JH titers. Three hours after contests, wasps who interacted with rivals signaling high fighting ability have higher JH titers than wasps who interacted with rivals signaling low fighting ability. Therefore, ornaments influence hormone titers of both signalers and receivers. We demonstrate that relationships between hormones and ornaments are flexible and bidirectional rather than static and unidirectional. Dynamic relationships among ornaments, behavior, and physiology may be an important, but overlooked factor in the evolution of honest communication. PMID:27402762

  12. Evolutionary Endocrinology of Hormonal Rhythms: Juvenile Hormone Titer Circadian Polymorphism in Gryllus firmus.

    PubMed

    Zera, Anthony J

    2016-08-01

    Daily rhythms for hormonal traits are likely widespread and important aspects of organismal (e.g., life history) adaptation. Yet they remain substantially understudied, especially with respect to variable rhythms within species. The cricket, Gryllus firmus, exhibits a genetically polymorphic circadian rhythm for the blood titer of the key hormone, juvenile hormone (JH). Gryllus firmus is also wing-polymorphic, consisting of a dispersing morph that delays reproduction and a flightless morph with substantially enhanced egg production. JH circadian phenotype strongly covaries with morph type: The blood JH titer is strongly rhythmic in multiple populations artificially-selected for the dispersing morph (LW(f) = long wings with functional flight muscles) and is essentially arrhythmic in populations selected for the SW (short-winged) morph. Association between JH titer cycle and LW(f) morph is also found in natural populations of G. firmus and in several related species in the field. This is one of the very few studies of endocrine titer variation in natural populations of an insect. The morph-specific cycle is underlain by a circadian rhythm in hormone biosynthesis, which in turn is underlain by a rhythm in a brain neuropeptide regulator of JH biosynthesis. The morph-specific JH titer circadian cycle is also strongly correlated with a morph-specific daily rhythm in global gene expression. This is currently the only example of a genetically-variable hormone circadian rhythm in both the laboratory and field that is strongly associated with an ecologically important polymorphism. The extensive information on the underlying causes of the morph-specific JH titer rhythm, coupled with the strong association between the JH circadian rhythm and wing polymorphism makes this system in G. firmus an exceptional experimental model to investigate the mechanisms underlying circadian hormonal adaptations. Genetic polymorphism for the JH titer circadian rhythm in G. firmus is discussed

  13. Comparison of the effect of hormones on the hormone synthesis of Tetrahymena in medium or salt solution.

    PubMed

    Csaba, G; Lajkó, Eszter; Pállinger, Eva

    2010-11-01

    Tetrahymena pyriformis was maintained in TYM (tryptone-yeast medium) as well as in Losina salt solution. One hour treatment of 10⁻¹⁵ M histamine, serotonin or insulin was given before the histamine, serotonin, triiodothyronine and adrenocorticotropin contents of the cells were measured by flow cytometry after immunocytochemical staining. Maintenance in salt solution increased the hormone level in the cells, and use of the treatment hormone treatments further increased the endogenous hormone content relative to that in medium. The cells in salt mimic better the natural conditions, which means that the effects of hormones under more natural conditions are expressed to a greater extent than the exogenously given hormones in TYM typically used under laboratory conditions. Intercellular hormonal communication between the cells of a Tetrahymena population might assist in the survival of the individual cells.

  14. Associations of Testosterone and Sex Hormone Binding Globulin with Adipose Tissue Hormones in Midlife Women

    PubMed Central

    Wildman, Rachel P.; Wang, Dan; Fernandez, Ivonne; Mancuso, Peter; Santoro, Nanette; Scherer, Philipp E.; Sowers, MaryFran R.

    2014-01-01

    Objective Regulators of adipose tissue hormones remain incompletely understood, but may include sex hormones. As adipose tissue hormones have been shown to contribute to numerous metabolic and cardiovascular disorders, understanding their regulation in midlife women is of clinical importance. Therefore, we assessed the associations between testosterone (T) and sex hormone binding globulin (SHBG) with leptin, high molecular weight (HMW) adiponectin, and the soluble form of the leptin receptor (sOB-R) in healthy midlife women. Design and Methods Cross-sectional analyses were performed using data from 1,881 midlife women (average age 52.6 (±2.7) years) attending the sixth Annual follow-up visit of the multiethnic Study of Women’s Health Across the Nation. Results T was weakly negatively associated with both HMW adiponectin and sOB-R (r = −0.12 and r = −0.10, respectively; P < 0.001 for both), and positively associated with leptin (r = 0.17; P < 0.001). SHBG was more strongly and positively associated with both HMW adiponectin and sOB-R (r = 0.29 and r = 0.24, respectively; P < 0.001 for both), and more strongly and negatively associated with leptin (r = −0.27; P < 0.001). Adjustment for fat mass, insulin resistance, or waist circumference only partially diminished associations with HMW adiponectin and sOB-R, but attenuated associations with leptin. In conclusion, in these midlife women, lower SHBG values, and to a lesser extent, higher T levels, were associated with lower, or less favorable, levels of adiponectin and sOB-R, independent of fat mass. Conclusions These data suggest that variation in these adipose hormones resulting from lower SHBG levels, and possibly, though less likely, greater androgenicity, may contribute to susceptibility for metabolic and cardiovascular outcomes during midlife in women. PMID:23592672

  15. Chronic exposure to pentachlorophenol alters thyroid hormones and thyroid hormone pathway mRNAs in zebrafish.

    PubMed

    Yu, Li-Qin; Zhao, Gao-Feng; Feng, Min; Wen, Wu; Li, Kun; Zhang, Pan-Wei; Peng, Xi; Huo, Wei-Jie; Zhou, Huai-Dong

    2014-01-01

    Pentachlorophenol (PCP) is frequently detected in the aquatic environment and has been implicated as an endocrine disruptor in fish. In the present study, 4-month-old zebrafish (Danio rerio) were exposed to 1 of 4 concentrations of PCP (0.1, 1, 9, and 27 µg/L) for 70 d. The effects of PCP exposure on plasma thyroid hormone levels, and the expression levels of selected genes, were measured in the brain and liver. The PCP exposure at 27 µg/L resulted in elevated plasma thyroxine concentrations in male and female zebrafish and depressed 3, 5, 3'-triiodothyronine concentrations in males only. In both sexes, PCP exposure resulted in decreased messenger RNA (mRNA) expression levels of thyroid-stimulating hormone β-subunit (tshβ) and thyroid hormone receptor β (trβ) in the brain, as well as increased liver levels of uridine diphosphoglucuronosyl transferase (ugt1ab) and decreased deiodinase 1 (dio1). The authors also identified several sex-specific effects of PCP exposure, including changes in mRNA levels for deiodinase 2 (dio2), cytosolic sulfotransferase (sult1 st5), and transthyretin (ttr) genes in the liver. Environmental PCP exposure also caused an increased malformation rate in offspring that received maternal exposure to PCP. The present study demonstrates that chronic exposure to environmental levels of PCP alters plasma thyroid hormone levels, as well as the expression of genes associated with thyroid hormone signaling and metabolism in the hypothalamic-pituitary-thyroid (HPT) axis and liver, resulting in abnormal zebrafish development.

  16. Vitamin D interferes with transactivation of the growth hormone gene by thyroid hormone and retinoic acid.

    PubMed Central

    Garcia-Villalba, P; Jimenez-Lara, A M; Aranda, A

    1996-01-01

    The thyroid hormone, retinoic acid (RA), and vitamin D regulate gene expression by binding to similar receptors which act as ligand-inducible transcription factors. Incubation of pituitary GH4C1 cells with nanomolar concentrations of vitamin D markedly reduces the response of the rat growth hormone mRNA to thyroid hormone triiodothyronine (T3) and RA. The stimulation of growth hormone gene expression by both ligands is mediated by a common hormone response element (TREGH) present in the 5'-flanking region of the gene, and the inhibition caused by vitamin D is due to transcriptional interference of the vitamin D receptor on this DNA element. No inhibition of the basal promoter activity by the vitamin was observed. The response to T3 and RA of a heterologous promoter containing this element, the palindromic T3- and RA-responsive sequence TREPAL, or a direct repeat of the same motif is also inhibited by vitamin D. In contrast, vitamin D strongly induces the activity of constructs containing a vitamin D response element, and neither T3 nor RA reduces vitamin D-mediated transactivation. Transfection with an expression vector for the retinoid X receptor alpha (RXR alpha) increases transactivation by T3 and RA but does not abolish the inhibition caused by the vitamin. Gel retardation experiments show that the vitamin D receptor (VDR) as a heterodimer with RXR weakly binds to the T3- and RA-responsive elements. Additionally, VDR displaces binding of T3 and RA receptors in a dose-dependent manner. Our data suggest the formation of TR-VDR and RAR-VDR heterodimers with RXR. The fact that the same response element mediates opposite effects of at least four different nuclear receptors provides a greater complexity and flexibility of the transcriptional responses to their ligands. PMID:8524311

  17. Influence of prostaglandins and thyrotropin releasing hormone (TRH) on hormone secretion and growth in wether lambs.

    PubMed

    Davis, S L; Anfinson, M S; Klindt, J; Ohlson, D L

    1977-06-01

    A series of experiments were conducted in ewes and whether (castrate male) lambs to evaluate the influence of prostaglandins on secretion of anabolic hormones and to determine if repeated injections of prostaglandin (PG) F2alpha would chronically influence the secretion of these hormones and perhaps growth rate as well. A single intravenous injection of PGA1 and PGB1 (100 microgram/kg) exerted no significant (P greater than .10) influence on plasma concentrations of prolactin (PRL), growth hormone (GH) or thyrotropin (TSH) in ewes. PGA1, but not PGB1, stimulated an increase in the plasma concentration of insulin. Infusion of PGF2alpha for 5.5 hr into ewes resulted in increased (P less than .05) plasma concentrations of both GH and ARL while TSH and insulin were not significantly influenced. Prostaglandin F2alpha, when injected subcutaneously into wether lambs (10 mg twice weekly) stimulated (P less than .05) plasma GH concentrations after the first injection, but not after 3 weeks of treatment. Changes in plasma PRL or TSH were not observed consistently in the lambs treated chronically with PGF2alpha or TRH. Prostaglandin F2alpha, in the present studies, and PGE1 in previously reported studies (1-3), has been demonstrated to be stimulatory to the secretion of PRL and GH. In contrast, PGA1 and PGB1, which lack an 11-hydroxyl group, failed to influence the secretion of either PRL or GH. It would, therefore, appear that the 11-hydroxyl group is a structural requirement for prostaglandins to influence the secretion of these two hormones in sheep. Treatment with thyrotropin releasing hormone (TRH), alone or in combination with PGF 2alpha, significantly (P less than .05) increased growth rate (average daily gains) while PGF2alpha did not, despite the fact that both compounds exerted similar effects on plasma GH.

  18. Experiment K-7-22: Growth Hormone Regulation Synthesis and Secretion in Microgravity. Part 3; Plasma Analysis Hormone Measurements

    NASA Technical Reports Server (NTRS)

    Grindeland, R. E.; Popova, I. A.; Grossman, E.; Rudolph, I.

    1994-01-01

    Plasma from space flight and tail suspended rats was analyzed for a number of constituents in order to evaluate their metabolic status and endocrine function. The data presented here cover plasma hormone measurements. Corticosterone, thyroxine, and testosterone were measured by radioimmunoassay. Prolactin and growth hormone were measured by double antibody immunoassays using hormones and antisera prepared in house. Data were evaluated by analysis of variance.

  19. Interactions between antiepileptic drugs and hormones.

    PubMed

    Svalheim, Sigrid; Sveberg, Line; Mochol, Monika; Taubøll, Erik

    2015-05-01

    Antiepileptic drugs (AEDs) are known to have endocrine side effects in both men and women. These can affect fertility, sexuality, thyroid function, and bone health, all functions of major importance for well-being and quality of life. The liver enzyme inducing antiepileptic drugs (EIAEDs), like phenobarbital, phenytoin, and carbamazepine, and also valproate (VPA), a non-EIAED, are most likely to cause such side effects. AED treatment can alter the levels of different sex hormones. EIAEDs increase sex hormone binding globulin (SHBG) concentrations in both men and women. Over time, this elevation can lead to lower levels of bioactive testosterone and estradiol, which may cause menstrual disturbances, sexual problems, and eventually reduced fertility. VPA can cause weight gain in both men and women. In women, VPA can also lead to androgenization with increased serum testosterone concentrations, menstrual disturbances, and polycystic ovaries. Lamotrigine has not been shown to result in endocrine side effects. The newer AEDs have not yet been thoroughly studied, but case reports indicate that some of these drugs could also be suspected to cause such effects if endocrine changes commence after treatment initiation. It is important to be aware of possible endocrine side effects of AEDs as they can have a major impact on quality of life, and are, at least partly, reversible after AED discontinuation.

  20. Nuclear hormone receptors put immunity on sterols

    PubMed Central

    Santori, Fabio R.

    2015-01-01

    Nuclear hormone receptors (NHRs) are transcription factors regulated by small molecules. The functions of NHRs range from development of primary and secondary lymphoid organs, to regulation of differentiation and function of DCs, macrophages and T cells. The human genome has 48 classic (hormone and vitamin receptors) and non-classic (all others) NHRs; 17 non-classic receptors are orphans, meaning that the endogenous ligand is unknown. Understanding the function of orphan NHRs requires the identification of their natural ligands. The mevalonate pathway, including its sterol and non-sterol intermediates and derivatives, is a source of ligands for many classic and non-classic NHRs. For example, cholesterol biosynthetic intermediates (CBIs) are natural ligands for RORγ/γt. CBIs are universal endogenous metabolites in mammalian cells, and to study NHRs that bind CBIs requires ligand-free reporters system in sterol auxotroph cells. Furthermore, RORγ/γt shows broad specificity to sterol lipids, suggesting that RORγ/γt is either a general sterol sensor or specificity is defined by an abundant endogenous ligand. Unlike other NHRs, which regulate specific metabolic pathways, there is no connection between the genetic programs induced by RORγ/γt and ligand biosynthesis. In this review we summarize the roles of non-classic NHRs and their potential ligands in the immune system. PMID:26222181

  1. Interactions between antiepileptic drugs and hormones.

    PubMed

    Svalheim, Sigrid; Sveberg, Line; Mochol, Monika; Taubøll, Erik

    2015-05-01

    Antiepileptic drugs (AEDs) are known to have endocrine side effects in both men and women. These can affect fertility, sexuality, thyroid function, and bone health, all functions of major importance for well-being and quality of life. The liver enzyme inducing antiepileptic drugs (EIAEDs), like phenobarbital, phenytoin, and carbamazepine, and also valproate (VPA), a non-EIAED, are most likely to cause such side effects. AED treatment can alter the levels of different sex hormones. EIAEDs increase sex hormone binding globulin (SHBG) concentrations in both men and women. Over time, this elevation can lead to lower levels of bioactive testosterone and estradiol, which may cause menstrual disturbances, sexual problems, and eventually reduced fertility. VPA can cause weight gain in both men and women. In women, VPA can also lead to androgenization with increased serum testosterone concentrations, menstrual disturbances, and polycystic ovaries. Lamotrigine has not been shown to result in endocrine side effects. The newer AEDs have not yet been thoroughly studied, but case reports indicate that some of these drugs could also be suspected to cause such effects if endocrine changes commence after treatment initiation. It is important to be aware of possible endocrine side effects of AEDs as they can have a major impact on quality of life, and are, at least partly, reversible after AED discontinuation. PMID:25797888

  2. Nuclear hormone receptors put immunity on sterols.

    PubMed

    Santori, Fabio R

    2015-10-01

    Nuclear hormone receptors (NHRs) are transcription factors regulated by small molecules. The functions of NHRs range from development of primary and secondary lymphoid organs, to regulation of differentiation and function of DCs, macrophages and T cells. The human genome has 48 classic (hormone and vitamin receptors) and nonclassic (all others) NHRs; 17 nonclassic receptors are orphans, meaning that the endogenous ligand is unknown. Understanding the function of orphan NHRs requires the identification of their natural ligands. The mevalonate pathway, including its sterol and nonsterol intermediates and derivatives, is a source of ligands for many classic and nonclassic NHRs. For example, cholesterol biosynthetic intermediates (CBIs) are natural ligands for RORγ/γt. CBIs are universal endogenous metabolites in mammalian cells, and to study NHRs that bind CBIs requires ligand-free reporters system in sterol auxotroph cells. Furthermore, RORγ/γt shows broad specificity to sterol lipids, suggesting that RORγ/γt is either a general sterol sensor or specificity is defined by an abundant endogenous ligand. Unlike other NHRs, which regulate specific metabolic pathways, there is no connection between the genetic programs induced by RORγ/γt and ligand biosynthesis. In this review, we summarize the roles of nonclassic NHRs and their potential ligands in the immune system.

  3. Hypoparathyroidism: Replacement Therapy with Parathyroid Hormone

    PubMed Central

    Underbjerg, Line; Sikjaer, Tanja

    2015-01-01

    Hypoparathyroidism (HypoPT) is characterized by low serum calcium levels caused by an insufficient secretion of parathyroid hormone (PTH). Despite normalization of serum calcium levels by treatment with activated vitamin D analogues and calcium supplementation, patients are suffering from impaired quality of life (QoL) and are at increased risk of a number of comorbidities. Thus, despite normalization of calcium levels in response to conventional therapy, this should only be considered as an apparent normalization, as patients are suffering from a number of complications and calcium-phosphate homeostasis is not normalized in a physiological manner. In a number of recent studies, replacement therapy with recombinant human PTH (rhPTH(1-84)) as well as therapy with the N-terminal PTH fragment (rhPTH(1-34)) have been investigated. Both drugs have been shown to normalize serum calcium while reducing needs for activated vitamin D and calcium supplements. However, once a day injections cause large fluctuations in serum calcium. Twice a day injections diminish fluctuations, but don't restore the normal physiology of calcium homeostasis. Recent studies using pump-delivery have shown promising results on maintaining normocalcemia with minimal fluctuations in calcium levels. Further studies are needed to determine whether this may improve QoL and lower risk of complications. Such data are needed before replacement with the missing hormone can be recommended as standard therapy. PMID:26394728

  4. Gender, sex hormones and pulmonary hypertension.

    PubMed

    Austin, Eric D; Lahm, Tim; West, James; Tofovic, Stevan P; Johansen, Anne Katrine; Maclean, Margaret R; Alzoubi, Abdallah; Oka, Masahiko

    2013-04-01

    Most subtypes of pulmonary arterial hypertension (PAH) are characterized by a greater susceptibility to disease among females, although females with PAH appear to live longer after diagnosis. While this "estrogen paradoxȍ of enhanced female survival despite increased female susceptibility remains a mystery, recent progress has begun to shed light upon the interplay of sex hormones, the pathogenesis of pulmonary hypertension, and the right ventricular response to stress. For example, emerging data in humans and experimental models suggest that estrogens or differential sex hormone metabolism may modify disease risk among susceptible subjects, and that estrogens may interact with additional local factors such as serotonin to enhance the potentially damaging chronic effects of estrogens on the pulmonary vasculature. Regardless, it remains unclear why not all estrogenic compounds behave equally, nor why estrogens appear to be protective in certain settings but detrimental in others. The contribution of androgens and other compounds, such as dehydroepiandrosterone, to pathogenesis and possibly treatment must be considered as well. In this review, we will discuss the recent understandings on how estrogens, estrogen metabolism, dehydroepiandrosterone, and additional susceptibility factors may all contribute to the pathogenesis or potentially to the treatment of pulmonary hypertension, by evaluating current human, cell-based, and experimental model data.

  5. Use of growth hormone in children.

    PubMed

    Hindmarsh, Peter C; Dattani, Mehul T

    2006-05-01

    The introduction of recombinant DNA-derived human growth hormone (rhGH) in the mid-1980s allowed studies to be undertaken in a number of growth disorders other than the classic indication--growth-hormone deficiency (GHD). In patients with GHD, optimizing the dose and frequency of rhGH administration, and early instigation of therapy, has led to near-normalization of final height. The use of rhGH in the treatment of Turner syndrome, Prader-Willi syndrome, intrauterine growth restriction, and chronic renal failure demonstrated the efficacy of therapy, although the increase in final height (5-7 cm) is less than that achieved in GHD. Cost-benefit implications need to be considered in the next phases of evaluating the role of rhGH therapy in these indications. To date, rhGH has only received approval for the management of idiopathic short stature in the US; as with the other wider growth indications, the lack of formal randomized, controlled trials hampers the full evaluation of efficacy, and a cautious approach should, therefore, be adopted for this particular indication. rhGH has a good safety record, although there are current concerns about the possible long-term increased risk of colonic and lymphatic malignancy, which will require monitoring through national cancer registries. PMID:16932297

  6. Growth hormone secretagogues: prospects and potential pitfalls.

    PubMed

    Smith, Roy G; Sun, Yuxiang; Betancourt, Lorena; Asnicar, Mark

    2004-09-01

    The growth hormone secretagogues (GHSs) are the first well-characterised agents that rejuvenate the growth hormone (GH)/insulin-like growth factor (IGF-1) axis. This property was discovered during investigations of the underlying causative mechanisms of age-related endocrine changes. Chronic administration of the long acting GHS, MK-0677, reverses the age-related decline in pulse-amplitude of GH secretion and restores IGF-1 levels producing profiles typical of young adults. This restoration is accompanied by improvements in body composition in frail elderly subjects. When given acutely, the GHSs also increase appetite. Following cloning and characterisation of the GHS-receptor (GHS-R) an endogenous ligand, ghrelin, was isolated and identified. Ghrelin shares the GH releasing and orexigenic properties of the GHSs. Studies using Ghsr-null mice confirmed that the GHS-R was the ghrelin-receptor; hence, the GHSs should be considered to be 'ghrelin mimetics.' Ghrelin levels are reported to decline during ageing, therefore long-acting GHSs are ideal candidates for ghrelin replacement therapy. PMID:15261841

  7. Degradation of parathyroid hormone in macrophage endosomes

    SciTech Connect

    Diment, S.; Martin, K.J.; Stahl, P.D.

    1986-05-01

    Parathyroid hormone (PTH) is secreted as an 84 amino acid protein that is rapidly cleaved between amino acids 34 and 35 by Kupffer cells in liver. The resulting amino terminal peptide (1-34) is active at PTH target organs (kidney and bone). Cathepsin D can process PTH to 1-34 in vitro, and a cathepsin D-like protease, which may rapidly process proteins, is present in endosomes of alveolar macrophages. The authors set out to determine whether PTH is degraded to 1-34 in endosomes, and to elucidate the mechanism of hormone processing in vivo. Intracellular transport of /sup 125/I-PTH was assessed by binding to alveolar macrophages at 4/sup 0/C, followed by internalization at 37/sup 0/C. Distribution of PTH among plasma membranes, endosomes and lysosomes was determined by subcellular fractionation. Degradation of the ligand to TCA-soluble fragments in each compartment was assayed at neutral and acid pH. 1-34 in supernatants was separated from undergraded PTH by gel filtration and detected by bioassay on kidney membranes. The authors data suggest that: 1) macrophages rapidly degrade PTH to TCA-soluble fragments. 2) macrophages do not secrete proteases that degrade extracellular PTH. 3) PTH is internalized into endocytic vesicles after 5 mins, but not delivered to lysosomes within 30 mins. 4) A bioactive peptide is released into the extracellular medium after 20 mins. 5) PTH is degraded in endosomes at acid pH by a pepstatin-sensitive protease.

  8. Parathyroid hormone levels predict posttotal thyroidectomy hypoparathyroidism.

    PubMed

    Rivere, Amy E; Brooks, Ashton J; Hayek, Genevieve A; Wang, Heng; Corsetti, Ralph L; Fuhrman, George M

    2014-08-01

    We hypothesized that parathyroid hormone (PTH) determination would be the most effective strategy to identify posttotal thyroidectomy hypoparathyroidism (PTTHP) compared with other clinical and laboratory parameters. We retrospectively reviewed our recent experience with total thyroidectomy. We recorded demographics, malignancy, thyroid weight, parathyroid autotransplantation, hospital stay, use of postoperative calcium and hormonally active vitamin D3 (calcitriol), and postoperative serum calcium and PTH levels. Patients were divided into two groups depending on whether supplemental calcitriol was required to maintain eucalcemia and therefore reflecting the diagnosis of PTTHP. From October 2010 to June 2013, a total of 202 total thyroidectomies were performed. Twenty-four patients (12%) developed PTTHP and required calcitriol replacement. Logistic regression analysis revealed that only postoperative calcium levels (P = 0.02) and PTH levels (P < 0.0001) statistically significantly predicted PTTHP. Twenty-two of 29 patients with PTH 13 pg/mL or less had PTTHP. Only two of 173 patients with a PTH level greater than 13 pg/mL were diagnosed with PTTHP. We recommend using PTH levels after total thyroidectomy to determine which patients will have hypoparathyroidism requiring calcitriol therapy. An early determination of PTTHP allows for prompt management that can shorten hospital stay and improve outcomes.

  9. Menopausal hormone therapy and venous thromboembolism

    PubMed Central

    2014-01-01

    Menopausal hormone therapy (MHT) is the most effective method of treating vasomotor symptoms and other climacteric symptoms related to estrogen deficiency in peri- and postmenopausal period. In addition to estrogen replacement, women with preserved uterus require the addition of progestagen in order to ensure endometrial safety. One of rare but severe complications of MHT is venous thromboembolism (VTE). The incidence of VTE rises in parallel to women's age and body weight. The condition is also linked to hereditary and acquired risk factors. Oral estrogens increase the risk of venous thromboembolic complications to varying extents, probably depending on their type and dose used. Observational studies have not found an association between an increased risk of VTE and transdermal estrogen treatment regardless of women's age and body mass index (BMI). Micronized progesterone and pregnanes, including dydrogesterone, have no effect on the risk of VTE, whereas norpregnane progestagens cause an additional increase in risk. Among hormonal preparations which are commercially available in Poland, the combination of transdermal estradiol with oral dydrogesterone appears to be the optimum choice, as it does not elevate the risk of VTE (compared to patients not using MHT), and dydrogesterone seems to be the progestagen of choice. PMID:26327865

  10. ``Sex Hormones'' in Secondary School Biology Textbooks

    NASA Astrophysics Data System (ADS)

    Nehm, Ross H.; Young, Rebecca

    2008-11-01

    This study explores the extent to which the term “sex hormone” is used in science textbooks, and whether the use of the term “sex hormone” is associated with pre-empirical concepts of sex dualism, in particular the misconceptions that these so-called “sex hormones” are sex specific and restricted to sex-related physiological functioning. We found that: (1) all the texts employed the term “sex hormone”; (2) in all texts estrogen is characterized as restricted to females and testosterone is characterized as restricted to males; and (3) in all texts testosterone and estrogen are discussed as exclusively involved in sex-related physiological roles. We conclude that (1) contemporary science textbooks preserve sex-dualistic models of steroid hormones (one sex, one “sex hormone”) that were rejected by medical science in the early 20th century and (2) use of the term “sex hormone” is associated with misconceptions regarding the presence and functions of steroid hormones in male and female bodies.

  11. Outcome of growth hormone therapy in children with growth hormone deficiency showing an inadequate response to growth hormone-releasing hormone.

    PubMed

    Saenger, P; Pescovitz, O H; Bercu, B B; Murray, F T; Landy, H; Brentzel, J; O'Dea, L; Hanson, B; Howard, C; Reiter, E O

    2001-06-01

    Saizen (recombinant growth hormone [GH]), 0.2 mg/(kg x wk), was given in an open-label fashion for an average of 51 mo to 27 children with presumed idiopathic GH deficiency who had withdrawn from a trial of Geref (recombinant GH-releasing hormone [GHRH] 1-29) because of inadequate height velocity (HV) (25 children), the onset of puberty (1 child), or injection site reactions (1 child). Measurements were made every 3-12 mo of a number of auxologic variables, including HV, height standard deviation score, and bone age. The children in the study showed excellent responses to Saizen. Moreover, first-year growth during Saizen therapy was inversely correlated with the GH response to provocative GHRH testing carried out 6 and 12 mo after the initiation of Geref treatment. These findings indicate that GH is effective in accelerating growth in GH-deficient children who do not show or maintain a satisfactory response to treatment with GHRH. In addition, they suggest that the initial response to GH therapy used in this way can be predicted by means of provoc-ative testing.

  12. Hypoparathyroidism: Replacement Therapy with Parathyroid Hormone.

    PubMed

    Rejnmark, Lars; Underbjerg, Line; Sikjaer, Tanja

    2015-12-01

    Hypoparathyroidism (HypoPT) is characterized by low serum calcium levels caused by an insufficient secretion of parathyroid hormone (PTH). Despite normalization of serum calcium levels by treatment with activated vitamin D analogues and calcium supplementation, patients are suffering from impaired quality of life (QoL) and are at increased risk of a number of comorbidities. Thus, despite normalization of calcium levels in response to conventional therapy, this should only be considered as an apparent normalization, as patients are suffering from a number of complications and calcium-phosphate homeostasis is not normalized in a physiological manner. In a number of recent studies, replacement therapy with recombinant human PTH (rhPTH(1-84)) as well as therapy with the N-terminal PTH fragment (rhPTH(1-34)) have been investigated. Both drugs have been shown to normalize serum calcium while reducing needs for activated vitamin D and calcium supplements. However, once a day injections cause large fluctuations in serum calcium. Twice a day injections diminish fluctuations, but don't restore the normal physiology of calcium homeostasis. Recent studies using pump-delivery have shown promising results on maintaining normocalcemia with minimal fluctuations in calcium levels. Further studies are needed to determine whether this may improve QoL and lower risk of complications. Such data are needed before replacement with the missing hormone can be recommended as standard therapy. PMID:26394728

  13. Detecting growth hormone misuse in athletes.

    PubMed

    Holt, Richard I G

    2013-10-01

    Athletes have been misusing growth hormone (GH) for its anabolic and metabolic effects since the early 1980s, at least a decade before endocrinologists began to treat adults with GH deficiency. Although there is an ongoing debate about whether GH is performance enhancing, recent studies suggest that GH improves strength and sprint capacity, particularly when combined with anabolic steroids. The detection of GH misuse is challenging because it is an endogenous hormone. Two approaches have been developed to detect GH misuse; the first is based on the measurement of pituitary GH isoforms and the ratio of 22-kDa isoform to total GH. The second is based on the measurement of insulin like growth factor-I (IGF-I) and N-terminal propeptide of type III procollagen (P-III-NP) which increase in a dose-dependent manner in response to GH administration. Both methodologies have been approved by the World Anti-Doping Agency (WADA) and have led to the detection of a number of athletes misusing GH.

  14. Gender, sex hormones and pulmonary hypertension

    PubMed Central

    Austin, Eric D.; Lahm, Tim; West, James; Tofovic, Stevan P.; Johansen, Anne Katrine; MacLean, Margaret R.; Alzoubi, Abdallah; Oka, Masahiko

    2013-01-01

    Most subtypes of pulmonary arterial hypertension (PAH) are characterized by a greater susceptibility to disease among females, although females with PAH appear to live longer after diagnosis. While this “estrogen paradoxȍ of enhanced female survival despite increased female susceptibility remains a mystery, recent progress has begun to shed light upon the interplay of sex hormones, the pathogenesis of pulmonary hypertension, and the right ventricular response to stress. For example, emerging data in humans and experimental models suggest that estrogens or differential sex hormone metabolism may modify disease risk among susceptible subjects, and that estrogens may interact with additional local factors such as serotonin to enhance the potentially damaging chronic effects of estrogens on the pulmonary vasculature. Regardless, it remains unclear why not all estrogenic compounds behave equally, nor why estrogens appear to be protective in certain settings but detrimental in others. The contribution of androgens and other compounds, such as dehydroepiandrosterone, to pathogenesis and possibly treatment must be considered as well. In this review, we will discuss the recent understandings on how estrogens, estrogen metabolism, dehydroepiandrosterone, and additional susceptibility factors may all contribute to the pathogenesis or potentially to the treatment of pulmonary hypertension, by evaluating current human, cell-based, and experimental model data. PMID:24015330

  15. Thyroid: biological actions of 'nonclassical' thyroid hormones.

    PubMed

    Senese, Rosalba; Cioffi, Federica; de Lange, Pieter; Goglia, Fernando; Lanni, Antonia

    2014-05-01

    Thyroid hormones (THs) are produced by the thyroid gland and converted in peripheral organs by deiodinases. THs regulate cell functions through two distinct mechanisms: genomic (nuclear) and nongenomic (non-nuclear). Many TH effects are mediated by the genomic pathway--a mechanism that requires TH activation of nuclear thyroid hormone receptors. The overall nongenomic processes, emerging as important accessory mechanisms in TH actions, have been observed at the plasma membrane, in the cytoplasm and cytoskeleton, and in organelles. Some products of peripheral TH metabolism (besides triiodo-L-thyronine), now termed 'nonclassical THs', were previously considered as inactive breakdown products. However, several reports have recently shown that they may have relevant biological effects. The recent accumulation of knowledge on how classical and nonclassical THs modulate the activity of membrane receptors, components of the mitochondrial respiratory chain, kinases and deacetylases, opened the door to the discovery of new pathways through which they act. We reviewed the current state-of-the-art on the actions of the nonclassical THs, discussing the role that these endogenous TH metabolites may have in the modulation of thyroid-related effects in organisms with differing complexity, ranging from nonmammals to humans.

  16. MULTIPLE STABLE PERIODIC SOLUTIONS IN A MODEL FOR THE HORMONAL REGULATION OF THE MENSTRUAL CYCLE

    EPA Science Inventory

    ABSTRACT

    The pituitary hormones, luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the ovarian hormones, estradiol (E2), progesterone (P4), and inhibin (Ih), are five hormones important for the regulation and maintenance of the human menstrual cycle. The...

  17. Effect of Growth Hormone Deficiency on Brain Structure, Motor Function and Cognition

    ERIC Educational Resources Information Center

    Webb, Emma A.; O'Reilly, Michelle A.; Clayden, Jonathan D.; Seunarine, Kiran K.; Chong, Wui K.; Dale, Naomi; Salt, Alison; Clark, Chris A.; Dattani, Mehul T.

    2012-01-01

    The growth hormone-insulin-like growth factor-1 axis plays a role in normal brain growth but little is known of the effect of growth hormone deficiency on brain structure. Children with isolated growth hormone deficiency (peak growth hormone less than 6.7 [micro]g/l) and idiopathic short stature (peak growth hormone greater than 10 [micro]g/l)…

  18. The Ontogenesis of Human Fetal Hormones

    PubMed Central

    Kaplan, S. L.; Grumbach, M. M.; Shepard, T. H.

    1972-01-01

    The content and concentration of immunoreactive growth hormone (GH) were measured in 117 human fetal pituitary glands from 68 days of gestation to term and in the pituitary glands of 20 children 1 month to 9 yr of age. Physicochemical and immunochemical properties of GH of fetal pituitary glands and GH from adult pituitary glands were indistinguishable by disc gel electrophoresis, immunoelectrophoresis, starch gel electrophoresis, and radioimmunoassay techniques. In the fetal pituitary gland, the GH content rose from mean levels of 0.44±0.2 μg at 10-14 wk of gestation, to 9.21±2.31 μg at 15-19 wk, to 59.38±11.08 μg at 20-24 wk, to 225.93±40.49 μg at 25-29 wk, to 577.67±90 μg at 30-34 wk, and to 675.17±112.33 μg at 35-40 wk. There was a significant positive correlation between growth hormone content of the pituitary and gestational age, crown-rump length, and the weight of the pituitary gland. The content and concentration (micrograms/milligram) of human growth hormone (HGH) in the fetal pituitary showed significant increments (P < 0.001) for each 4 wk period of gestation until 35 wk. Further increases in the HGH content were noted in pituitaries of children aged 1-9 yr (range of 832 to 11.211 μg). Immunoreactive GH was detected in fetal serum at a concentration of 14.5 ng/ml as early as 70 days gestation, the youngest fetus assayed. At 10-14 wk, the mean concentration of serum growth hormone was 65.2±7.6 ng/ml; at 15-19 wk 114.9±12.5 ng/ml; at 20-24 wk 119.3±19.8 ng/ml; at 25-29 wk 72.0±11.5 ng/ml; and 33.5±4.2 ng/ml at term. A significant negative correlation of serum growth hormone with advancing gestational age after 20-24 wk was observed (P < 0.001). In 17 fetuses paired serum and pituitary samples were assayed; no significant correlation between the concentration of serum GH and the pituitary content or concentration of GH was demonstrable. The serum concentration of chorionic somatomammotropin (HCS) in the fetus was unrelated to gestational

  19. Pediatric stress: hormonal mediators and human development.

    PubMed

    Charmandari, Evangelia; Kino, Tomoshige; Souvatzoglou, Emmanuil; Chrousos, George P

    2003-01-01

    Stress activates the central and peripheral components of the stress system, i.e., the hypothalamic-pituitary-adrenal (HPA) axis and the arousal/sympathetic system. The principal effectors of the stress system are corticotropin-releasing hormone (CRH), arginine vasopressin, the proopiomelanocortin-derived peptides alpha-melanocyte-stimulating hormone and beta-endorphin, the glucocorticoids, and the catecholamines norepinephrine and epinephrine. Appropriate responsiveness of the stress system to stressors is a crucial prerequisite for a sense of well-being, adequate performance of tasks and positive social interactions. By contrast, inappropriate responsiveness of the stress system may impair growth and development, and may account for a number of endocrine, metabolic, autoimmune and psychiatric disorders. The development and severity of these conditions primarily depend on the genetic vulnerability of the individual, the exposure to adverse environmental factors and the timing of the stressful event(s), given that prenatal life, infancy, childhood and adolescence are critical periods characterized by increased vulnerability to stressors. The developing brain undergoes rapid growth and is characterized by high turnover of neuronal connections during the prenatal and early postnatal life. These processes and, hence, brain plasticity, slow down during childhood and puberty, and plateau in young adulthood. Hormonal actions in early life, and to a much lesser extent later, can be organizational, i.e., can have effects that last for long periods of time, often for the entire life of the individual. Hormones of the stress system and sex steroids have such effects, which influence the behavior and certain physiologic functions of individuals for life. Exposure of the developing brain to severe and/or prolonged stress may result in hyperactivity/hyperreactivity of the stress system, with resultant amygdala hyperfunction (fear reaction), decreased activity of the hippocampus

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

    PubMed

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

    2015-08-01

    Di-(2-ethylhexyl) phthalate (DEHP) is used extensively in many personal care and consumer products, resulting in widespread nonoccupational human exposure through multiple routes and media. Limited studies suggest that exposure to DEHP may be associated with altered thyroid function, but detailed mechanisms are unclear. In order to elucidate potential mechanisms by which DEHP disturbs thyroid hormone homeostasis, Sprague-Dawley (SD) rats were dosed with DEHP by gavage at 0, 250, 500, and 750 mg/kg/day for 30 days and sacrificed within 24 h after the last dose. Gene expressions of thyroid hormone receptors, deiodinases, transthyretin, and hepatic enzymes were measured by RT-PCR; protein levels of transthyretin were also analyzed by Western blot. Results showed that DEHP caused histological changes in the thyroid and follicular epithelial cell hypertrophy and hyperplasia were observed. DEHP significantly reduced thyroid hormones (T3, T4) and thyrotropin releasing hormone (TRH) levels, whereas thyroid stimulating hormone (TSH) was not affected. After exposure to DEHP, biosynthesis of thyroid hormones was suppressed, and sodium iodide symporter (NIS) and thyroid peroxidase (TPO) levels were significantly reduced. Additionally, levels of deiodinases and transthyretin were also affected. TSH receptor (TSHr) level was downregulated, while TRH receptor (TRHr) level was upregulated. Metabolism of thyroid hormones was accelerated due to elevated gene expression of hepatic enzymes (UDPGTs and CYP2B1) by DEHP. Taken together, observed findings indicate that DEHP could reduce thyroid hormones through influencing biosynthesis, biotransformation, biotransport, receptor levels, and metabolism of thyroid hormones. PMID:25913319