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Sample records for interleukin-1 receptor phosphorylation

  1. JAK1 kinase forms complexes with interleukin-4 receptor and 4PS/insulin receptor substrate-1-like protein and is activated by interleukin-4 and interleukin-9 in T lymphocytes.

    Science.gov (United States)

    Yin, T; Tsang, M L; Yang, Y C

    1994-10-28

    Interleukin (IL)-4 and IL-9 regulate the proliferation of T lymphocytes through interactions with their receptors. Previous studies have shown that unknown tyrosine kinases are involved in the proliferative signaling triggered by IL-4 and IL-9. Here we show that IL-4 and IL-9 induce overlapping (170, 130, and 125 kilodalton (kDa)) and distinct (45 and 88/90 kDa, respectively) protein tyrosine phosphorylation in T lymphocytes. We further identify the 170-kDa tyrosine-phosphorylated protein as 4PS/insulin receptor substrate-1-like (IRS-1L) protein and 130-kDa protein as JAK1 kinase. Furthermore, we demonstrate for the first time that JAK1 forms complexes with the IL-4 receptor and 4PS/IRS-1L protein following ligand-receptor interaction. In addition, we demonstrate that IL-9, but not IL-4, induced tyrosine phosphorylation of Stat 91 transcriptional factor. The overlapping and distinct protein tyrosine phosphorylation and activation of the same JAK1 kinase in T lymphocytes strongly suggests that IL-4 and IL-9 share the common signal transduction pathways and that the specificity for each cytokine could be achieved through the unique tyrosine-phosphorylated proteins triggered by individual cytokines.

  2. Interleukins 2, 4, 7, and 15 stimulate tyrosine phosphorylation of insulin receptor substrates 1 and 2 in T cells. Potential role of JAK kinases.

    Science.gov (United States)

    Johnston, J A; Wang, L M; Hanson, E P; Sun, X J; White, M F; Oakes, S A; Pierce, J H; O'Shea, J J

    1995-12-01

    The signaling molecules insulin receptor substrate (IRS)-1 and the newly described IRS-2 (4PS) molecule are major insulin and interleukin 4 (IL-4)-dependent phosphoproteins. We report here that IL-2, IL-7, and IL-15, as well as IL-4, rapidly stimulate the tyrosine phosphorylation of IRS-1 and IRS-2 in human peripheral blood T cells, NK cells, and in lymphoid cell lines. In addition, we show that the Janus kinases, JAK1 and JAK3, associate with IRS-1 and IRS-2 in T cells. Coexpression studies demonstrate that these kinases can tyrosine-phosphorylate IRS-2, suggesting a possible mechanism by which cytokine receptors may induce the tyrosine phosphorylation of IRS-1 and IRS-2. We further demonstrate that the p85 subunit of phosphoinositol 3-kinase associates with IRS-1 in response to IL-2 and IL-4 in T cells. Therefore, these data indicate that IRS-1 and IRS-2 may have important roles in T lymphocyte activation not only in response to IL-4, but also in response to IL-2, IL-7, and IL-15.

  3. Signaling pathways of interleukin-1 actions in the brain: anatomical distribution of phospho-ERK1/2 in the brain of rat treated systemically with interleukin-1beta.

    Science.gov (United States)

    Nadjar, A; Combe, C; Busquet, P; Dantzer, R; Parnet, P

    2005-01-01

    Interleukin-1beta is released at the periphery during infection and acts on the nervous system to induce fever, neuroendocrine activation, and behavioral changes. These effects are mediated by brain type I IL-1 receptors. In vitro studies have shown the ability of interleukin-1beta to activate mitogen-activated protein kinase signaling pathways including p38, c-Jun N-terminal kinase and extracellular signal-regulated protein kinase 1 and 2 (ERK1/2). In contrast to other mitogen-activated protein kinases, little is known about ERK1/2 activation in the rat brain in response to interleukin-1beta. The aim of the present study was therefore to investigate spatial and temporal activation of ERK1/2 in the rat brain after peripheral administration of interleukin-1beta using immunohistochemistry to detect the phosphorylated form of the kinase. In non-stimulated conditions, phosphorylated ERK1/2 immunoreactivity was observed in neurons throughout the brain. Administration of interleukin-1beta (60 microg/kg, i.p.) induced the phosphorylation of ERK1/2 in areas at the interface between brain and blood or cerebrospinal fluid: meninges, circumventricular organs, endothelial like cells of the blood vessels, and in brain nuclei involved in behavioral depression, fever and neuroendocrine activation: paraventricular nucleus of the hypothalamus, supraoptic nucleus, central amygdala and arcuate nucleus. Double labeling of phosphorylated ERK1/2 and cell markers revealed the expression of phosphorylated ERK1/2 in neurons, astrocytes and microglia. Since phosphorylated ERK1/2 was found in structures in which type I IL-1 receptor has already been identified as well as in structures lacking this receptor, activation of ERK1/2 is likely to occur in response to both direct and indirect action of interleukin-1beta on its target cells.

  4. The insulin receptor substrate-1-related 4PS substrate but not the interleukin-2R gamma chain is involved in interleukin-13-mediated signal transduction.

    Science.gov (United States)

    Wang, L M; Michieli, P; Lie, W R; Liu, F; Lee, C C; Minty, A; Sun, X J; Levine, A; White, M F; Pierce, J H

    1995-12-01

    Interleukin-13 (IL-13) induced a potent mitogenic response in IL-3-dependent TF-1 cells and DNA synthesis to a lesser extent in MO7E and FDC-P1 cells. IL-13 stimulation of these lines, like IL-4 and insulin-like growth factor-1 (IGF-1), resulted in tyrosine phosphorylation of a 170-kD substrate. The tyrosine-phosphorylated 170-kD substrate strongly associated with the 85-kD subunit of phosphoinositol-3 (PI-3) kinase and with Grb-2. Anti-4PS serum readily detected the 170-kD substrate in lysates from both TF-1 and FDC-P1 cells stimulated with IL-13 or IL-4. These data provide evidence that IL-13 induces tyrosine phosphorylation of the 4PS substrate, providing an essential interface between the IL-13 receptor and signaling molecules containing SH2 domains. IL-13 and IL-4 stimulation of murine L cell fibroblasts, which endogenously express the IL-4 receptor (IL-4R alpha) and lack expression of the IL-2 receptor gamma subunit (IL-2R gamma), resulted in tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1)/4PS. Enhanced tyrosine phosphorylation of IRS-1/4PS was observed in response to IL-4, but not IL-13 treatment of L cells transfected with the IL-2R gamma chain. These results indicate that IL-13 does not use the IL-2R gamma subunit in its receptor complex and that expression of IL-2R gamma enhances, but is not absolutely required for mediating IL-4-induced tyrosine phosphorylation of IRS-1/4PS.

  5. Interleukin 1β induces rapid phosphorylation and redistribution of talin: A possible mechanism for modulation of fibroblast focal adhesion

    International Nuclear Information System (INIS)

    Qwarnstroem, E.E.; MacFarlane, S.A.; Page, R.C.; Dower, S.K.

    1991-01-01

    The majority of interleukin 1 (IL-1) receptors in human fibroblasts has been shown to be localized at focal adhesions. This study describes rapid alterations caused by IL-1β/IL-1-receptor interaction at these sites. Fibroblast monolayers, incubated with IL-1β and prepared for electron microscopy, showed successive loss of cell-substratum contact and fewer and less-pronounced processes. Immunocytochemistry revealed loss and redistribution of the talin staining initially observed after 5-15 min of IL-1β incubation. Similarly, the cytoskeleton showed a decrease in staining and a disorganization starting from 15 to 30 min after IL-1 addition, whereas extracellular fibronectin appeared largely unaffected. Prelabeling with [ 32 P]phosphate showed a 2- to 3-fold increase in the level of talin phosphorylation, peaking at 15 min. Phospho amino acid analyses revealed a higher level of serine and threonine phosphorylation. The data suggest that the action of IL-1β on fibroblasts may be partially mediated by direct phosphorylation of talin via activation of a protein serine/threonine kinase, leading to changes in transmembrane linkage proteins and the cytoskeleton. Such alterations at focal adhesions may provide a mechanism by which IL-1 can rapidly modulate cell-matrix interactions during inflammation and wound healing

  6. The interleukin-4 receptor: signal transduction by a hematopoietin receptor.

    Science.gov (United States)

    Keegan, A D; Pierce, J H

    1994-02-01

    Over the last several years, the receptors for numerous cytokines have been molecularly characterized. Analysis of their amino acid sequences shows that some of these receptors bear certain motifs in their extracellular domains that define a family of receptors called the Hematopoietin receptor superfamily. Significant advances in characterizing the structure, function, and mechanisms of signal transduction have been made for several members of this family. The purpose of this review is to discuss the recent advances made for one of the family members, the interleukin (IL) 4 receptor. Other receptor systems have recently been reviewed elsewhere. The IL-4 receptor consists of, at the minimum, the cloned 140 kDa IL-4-binding chain with the potential for associating with other chains. The IL-4 receptor transduces its signal by activating a tyrosine kinase that phosphorylates cellular substrates, including the receptor itself, and the 170 kDa substrate called 4PS. Phosphorylated 4PS interacts with the SH2 domain of the enzyme PI-3'-kinase and increases its enzymatic activity. These early events in the IL-4 receptor initiated signaling pathway may trigger a series of signals that will ultimately lead to an IL-4 specific biologic outcome.

  7. Interleukin-1-receptor antagonist in type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Larsen, Claus M; Faulenbach, Mirjam; Vaag, Allan

    2007-01-01

    BACKGROUND: The expression of interleukin-1-receptor antagonist is reduced in pancreatic islets of patients with type 2 diabetes mellitus, and high glucose concentrations induce the production of interleukin-1beta in human pancreatic beta cells, leading to impaired insulin secretion, decreased cell...... proliferation, and apoptosis. METHODS: In this double-blind, parallel-group trial involving 70 patients with type 2 diabetes, we randomly assigned 34 patients to receive 100 mg of anakinra (a recombinant human interleukin-1-receptor antagonist) subcutaneously once daily for 13 weeks and 36 patients to receive...... placebo. At baseline and at 13 weeks, all patients underwent an oral glucose-tolerance test, followed by an intravenous bolus of 0.3 g of glucose per kilogram of body weight, 0.5 mg of glucagon, and 5 g of arginine. In addition, 35 patients underwent a hyperinsulinemic-euglycemic clamp study. The primary...

  8. New Role for Interleukin-13 Receptor α1 in Myocardial Homeostasis and Heart Failure.

    Science.gov (United States)

    Amit, Uri; Kain, David; Wagner, Allon; Sahu, Avinash; Nevo-Caspi, Yael; Gonen, Nir; Molotski, Natali; Konfino, Tal; Landa, Natalie; Naftali-Shani, Nili; Blum, Galia; Merquiol, Emmanuelle; Karo-Atar, Danielle; Kanfi, Yariv; Paret, Gidi; Munitz, Ariel; Cohen, Haim Y; Ruppin, Eytan; Hannenhalli, Sridhar; Leor, Jonathan

    2017-05-20

    The immune system plays a pivotal role in myocardial homeostasis and response to injury. Interleukins-4 and -13 are anti-inflammatory type-2 cytokines, signaling via the common interleukin-13 receptor α1 chain and the type-2 interleukin-4 receptor. The role of interleukin-13 receptor α1 in the heart is unknown. We analyzed myocardial samples from human donors (n=136) and patients with end-stage heart failure (n=177). We found that the interleukin-13 receptor α1 is present in the myocardium and, together with the complementary type-2 interleukin-4 receptor chain Il4ra , is significantly downregulated in the hearts of patients with heart failure. Next, we showed that Il13ra1 -deficient mice develop severe myocardial dysfunction and dyssynchrony compared to wild-type mice (left ventricular ejection fraction 29.7±9.9 versus 45.0±8.0; P =0.004, left ventricular end-diastolic diameter 4.2±0.2 versus 3.92±0.3; P =0.03). A bioinformatic analysis of mouse hearts indicated that interleukin-13 receptor α1 regulates critical pathways in the heart other than the immune system, such as extracellular matrix (normalized enrichment score=1.90; false discovery rate q=0.005) and glucose metabolism (normalized enrichment score=-2.36; false discovery rate q=0). Deficiency of Il13ra1 was associated with reduced collagen deposition under normal and pressure-overload conditions. The results of our studies in humans and mice indicate, for the first time, a role of interleukin-13 receptor α1 in myocardial homeostasis and heart failure and suggests a new therapeutic target to treat heart disease. © 2017 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

  9. Interleukin-1B and Interleukin-1 Receptor Antagonist in Patients with Helicobacter pylori Associated Diseases

    Directory of Open Access Journals (Sweden)

    Elizaveta S. Ageeva, PhD

    2012-06-01

    Full Text Available The ethnic people of the Republic of Khakassia (the Khakas with ulcer disease show a significant T-cell activation and humoral immune response when compared with the Europoids. The reasons for such differences could be due to certain ethno-specific allelic variants of the interleukins, which considerably change the degree of cytokine expression. The aim was to study the peculiarities of the association of the interleukin-1 (IL-1 gene polymorphisms and interleukin-1 receptor antagonist (IL-1Ra. Patients with chronic gastritis and ulcer disease were examined using the restriction analysis method. The most wide-spread allelic variants among the Khakas were discovered to be С�� IL-1β and R4R4 IL-1Ra. In this study, we suggest the necessity to define the population’s risk and the protective genotypes that promote Helicobacter pylori-associated ulcer disease among the Khakas people.

  10. DMPD: Modulation of Toll-interleukin 1 receptor mediated signaling. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 15662540 Modulation of Toll-interleukin 1 receptor mediated signaling. Li X, Qin J.... J Mol Med. 2005 Apr;83(4):258-66. Epub 2005 Jan 21. (.png) (.svg) (.html) (.csml) Show Modulation of Toll-i...nterleukin 1 receptor mediated signaling. PubmedID 15662540 Title Modulation of Toll-interleukin 1 receptor

  11. Cloning the interleukin 1 receptor from human T cells

    International Nuclear Information System (INIS)

    Sims, J.E.; Acres, R.B.; Grubin, C.E.; McMahan, C.J.; Wignall, J.M.; March, C.J.; Dower, S.K.

    1989-01-01

    cDNA clones of the interleukin 1 (IL-1) receptor expressed in a human T-cell clone have been isolated by using a murine IL-1 receptor cDNA as a probe. The human and mouse receptors show a high degree of sequence conservation. Both are integral membrane proteins possessing a single membrane-spanning segment. Similar to the mouse receptor, the human IL-1 receptor contains a large cytoplasmic region and an extracellular, IL-1 binding portion composed of three immunoglobulin-like domains. When transfected into COS cells, the human IL-1 receptor cDNA clone leads to expression of two different affinity classes of receptors, with K a values indistinguishable from those determined for IL-1 receptors in the original T-cell clone. An IL-1 receptor expressed in human dermal fibroblasts has also been cloned and sequenced and found to be identical to the IL-1 receptor expressed in T cells

  12. Activation of the protein tyrosine phosphatase SHP2 via the interleukin-6 signal transducing receptor protein gp130 requires tyrosine kinase Jak1 and limits acute-phase protein expression.

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    Schaper, F; Gendo, C; Eck, M; Schmitz, J; Grimm, C; Anhuf, D; Kerr, I M; Heinrich, P C

    1998-11-01

    Stimulation of the interleukin-6 (IL-6) signalling pathway occurs via the IL-6 receptor-glycoprotein 130 (IL-6R-gp130) receptor complex and results in the regulation of acute-phase protein genes in liver cells. Ligand binding to the receptor complex leads to tyrosine phosphorylation and activation of Janus kinases (Jak), phosphorylation of the signal transducing subunit gp130, followed by recruitment and phosphorylation of the signal transducer and activator of transcription factors STAT3 and STAT1 and the src homology domain (SH2)-containing protein tyrosine phosphatase (SHP2). The tyrosine phosphorylated STAT factors dissociate from the receptor, dimerize and translocate to the nucleus where they bind to enhancer sequences of IL-6 target genes. Phosphorylated SHP2 is able to bind growth factor receptor bound protein (grb2) and thus might link the Jak/STAT pathway to the ras/raf/mitogen-activated protein kinase pathway. Here we present data on the dose-dependence, kinetics and kinase requirements for SHP2 phosphorylation after the activation of the signal transducer, gp130, of the IL-6-type family receptor complex. When human fibrosarcoma cell lines deficient in Jak1, Jak2 or tyrosine kinase 2 (Tyk2) were stimulated with IL-6-soluble IL-6R complexes it was found that only in Jak1-, but not in Jak 2- or Tyk2-deficient cells, SHP2 activation was greatly impaired. It is concluded that Jak1 is required for the tyrosine phosphorylation of SHP2. This phosphorylation depends on Tyr-759 in the cytoplasmatic domain of gp130, since a Tyr-759-->Phe exchange abrogates SHP2 activation and in turn leads to elevated and prolonged STAT3 and STAT1 activation as well as enhanced acute-phase protein gene induction. Therefore, SHP2 plays an important role in acute-phase gene regulation.

  13. Hyperinsulinemia enhances interleukin-17-induced inflammation to promote prostate cancer development in obese mice through inhibiting glycogen synthase kinase 3-mediated phosphorylation and degradation of interleukin-17 receptor

    Science.gov (United States)

    Chen, Chong; Ge, Dongxia; Qu, Yine; Chen, Rongyi; Fan, Yi-Ming; Li, Nan; Tang, Wendell W.; Zhang, Wensheng; Zhang, Kun; Wang, Alun R.; Rowan, Brian G.; Hill, Steven M.; Sartor, Oliver; Abdel, Asim B.; Myers, Leann; Lin, Qishan; You, Zongbing

    2016-01-01

    Interleukin-17 (IL-17) plays important roles in inflammation, autoimmune diseases, and some cancers. Obese people are in a chronic inflammatory state with increased serum levels of IL-17, insulin, and insulin-like growth factor 1 (IGF1). How these factors contribute to the chronic inflammatory status that promotes development of aggressive prostate cancer in obese men is largely unknown. We found that, in obese mice, hyperinsulinemia enhanced IL-17-induced expression of downstream proinflammatory genes with increased levels of IL-17 receptor A (IL-17RA), resulting in development of more invasive prostate cancer. Glycogen synthase kinase 3 (GSK3) constitutively bound to and phosphorylated IL-17RA at T780, leading to ubiquitination and proteasome-mediated degradation of IL-17RA, thus inhibiting IL-17-mediated inflammation. IL-17RA phosphorylation was reduced, while the IL-17RA levels were increased in the proliferative human prostate cancer cells compared to the normal cells. Insulin and IGF1 enhanced IL-17-induced inflammatory responses through suppressing GSK3, which was shown in the cultured cell lines in vitro and obese mouse models of prostate cancer in vivo. These findings reveal a mechanism underlying the intensified inflammation in obesity and obesity-associated development of aggressive prostate cancer, suggesting that targeting GSK3 may be a potential therapeutic approach to suppress IL-17-mediated inflammation in the prevention and treatment of prostate cancer, particularly in obese men. PMID:26871944

  14. Interleukin 18 receptor 1 gene polymorphisms are associated with asthma

    DEFF Research Database (Denmark)

    Zhu, Guohua; Whyte, Moira K B; Vestbo, Jørgen

    2008-01-01

    The interleukin 18 receptor (IL18R1) gene is a strong candidate gene for asthma. It has been implicated in the pathophysiology of asthma and maps to an asthma susceptibility locus on chromosome 2q12. The possibility of association between polymorphisms in IL18R1 and asthma was examined by genotyp...

  15. Phosphorylation and Internalization of Lysophosphatidic Acid Receptors LPA1, LPA2, and LPA3.

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    Rocío Alcántara-Hernández

    Full Text Available The lysophosphatidic acid receptors LPA1, LPA2, and LPA3 were individually expressed in C9 cells and their signaling and regulation were studied. Agonist-activation increases intracellular calcium concentration in a concentration-dependent fashion. Phorbol myristate acetate markedly inhibited LPA1- and LPA3-mediated effect, whereas that mediated by LPA2 was only partially diminished; the actions of the phorbol ester were inhibited by bisindolylmaleimide I and by overnight incubation with the protein kinase C activator, which leads to down regulation of this protein kinase. Homologous desensitization was also observed for the three LPA receptors studied, with that of LPA2 receptors being consistently of lesser magnitude; neither inhibition nor down-regulation of protein kinase C exerted any effect on homologous desensitization. Activation of LPA1-3 receptors induced ERK 1/2 phosphorylation; this effect was markedly attenuated by inhibition of epidermal growth factor receptor tyrosine kinase activity, suggesting growth factor receptor transactivation in this effect. Lysophosphatidic acid and phorbol myristate acetate were able to induce LPA1-3 phosphorylation, in time- and concentration-dependent fashions. It was also clearly observed that agonists and protein kinase C activation induced internalization of these receptors. Phosphorylation of the LPA2 subtype required larger concentrations of these agents and its internalization was less intense than that of the other subtypes.Our data show that these three LPA receptors are phosphoproteins whose phosphorylation state is modulated by agonist-stimulation and protein kinase C-activation and that differences in regulation and cellular localization exist, among the subtypes.

  16. Gβ promotes pheromone receptor polarization and yeast chemotropism by inhibiting receptor phosphorylation.

    Science.gov (United States)

    Ismael, Amber; Tian, Wei; Waszczak, Nicholas; Wang, Xin; Cao, Youfang; Suchkov, Dmitry; Bar, Eli; Metodiev, Metodi V; Liang, Jie; Arkowitz, Robert A; Stone, David E

    2016-04-12

    Gradient-directed cell migration (chemotaxis) and growth (chemotropism) are processes that are essential to the development and life cycles of all species. Cells use surface receptors to sense the shallow chemical gradients that elicit chemotaxis and chemotropism. Slight asymmetries in receptor activation are amplified by downstream signaling systems, which ultimately induce dynamic reorganization of the cytoskeleton. During the mating response of budding yeast, a model chemotropic system, the pheromone receptors on the plasma membrane polarize to the side of the cell closest to the stimulus. Although receptor polarization occurs before and independently of actin cable-dependent delivery of vesicles to the plasma membrane (directed secretion), it requires receptor internalization. Phosphorylation of pheromone receptors by yeast casein kinase 1 or 2 (Yck1/2) stimulates their internalization. We showed that the pheromone-responsive Gβγ dimer promotes the polarization of the pheromone receptor by interacting with Yck1/2 and locally inhibiting receptor phosphorylation. We also found that receptor phosphorylation is essential for chemotropism, independently of its role in inducing receptor internalization. A mathematical model supports the idea that the interaction between Gβγ and Yck1/2 results in differential phosphorylation and internalization of the pheromone receptor and accounts for its polarization before the initiation of directed secretion. Copyright © 2016, American Association for the Advancement of Science.

  17. Phosphorylation of the dimeric cytoplasmic domain of the phytosulfokine receptor, PSKR1

    KAUST Repository

    Muleya, V.

    2016-08-04

    Phytosulfokines (PSKs) are plant peptide hormones that co-regulate plant growth, differentiation and defense responses. PSKs signal through a plasma membrane localized leucine-rich repeat receptor-like kinase (phytosulfokine receptor 1, PSKR1) that also contains a functional cytosolic guanylate cyclase with its cyclase catalytic center embedded within the kinase domain. To functionally characterize this novel type of overlapping dual catalytic function, we investigated the phosphorylation of PSKR1 in vitro Tandem mass spectrometry of the cytoplasmic domain of PSKR1 (PSKR1cd) revealed at least 11 phosphorylation sites (8 serines, 2 threonines and 1 tyrosine) within the PSKR1cd. Phosphomimetic mutations of three serine residues (Ser686, Ser696 and Ser698) in tandem at the juxta-membrane position resulted in enhanced kinase activity in the on-mutant that was suppressed in the off-mutant, but both mutations reduced guanylate cyclase activity. Both the on and off phosphomimetic mutations of the phosphotyrosine (Tyr888) residue in the activation loop suppressed kinase activity, while neither mutation affected guanylate cyclase activity. Size exclusion and analytical ultracentrifugation analysis of the PSKR1cd suggest that it is reversibly dimeric in solution, which was further confirmed by biflourescence complementation. Taken together, these data suggest that in this novel type of receptor domain architecture, specific phosphorylation and dimerization are possibly essential mechanisms for ligand-mediated catalysis and signaling.

  18. Phosphorylation of the dimeric cytoplasmic domain of the phytosulfokine receptor, PSKR1

    KAUST Repository

    Muleya, V.; Marondedze, Claudius; Wheeler, J. I.; Thomas, Ludivine; Mok, Y.-F.; Griffin, M. D. W.; Manallack, D. T.; Kwezi, L.; Lilley, K. S.; Gehring, Christoph A; Irving, H. R.

    2016-01-01

    Phytosulfokines (PSKs) are plant peptide hormones that co-regulate plant growth, differentiation and defense responses. PSKs signal through a plasma membrane localized leucine-rich repeat receptor-like kinase (phytosulfokine receptor 1, PSKR1) that also contains a functional cytosolic guanylate cyclase with its cyclase catalytic center embedded within the kinase domain. To functionally characterize this novel type of overlapping dual catalytic function, we investigated the phosphorylation of PSKR1 in vitro Tandem mass spectrometry of the cytoplasmic domain of PSKR1 (PSKR1cd) revealed at least 11 phosphorylation sites (8 serines, 2 threonines and 1 tyrosine) within the PSKR1cd. Phosphomimetic mutations of three serine residues (Ser686, Ser696 and Ser698) in tandem at the juxta-membrane position resulted in enhanced kinase activity in the on-mutant that was suppressed in the off-mutant, but both mutations reduced guanylate cyclase activity. Both the on and off phosphomimetic mutations of the phosphotyrosine (Tyr888) residue in the activation loop suppressed kinase activity, while neither mutation affected guanylate cyclase activity. Size exclusion and analytical ultracentrifugation analysis of the PSKR1cd suggest that it is reversibly dimeric in solution, which was further confirmed by biflourescence complementation. Taken together, these data suggest that in this novel type of receptor domain architecture, specific phosphorylation and dimerization are possibly essential mechanisms for ligand-mediated catalysis and signaling.

  19. Postoperative ileus involves interleukin-1 receptor signaling in enteric glia.

    Science.gov (United States)

    Stoffels, Burkhard; Hupa, Kristof Johannes; Snoek, Susanne A; van Bree, Sjoerd; Stein, Kathy; Schwandt, Timo; Vilz, Tim O; Lysson, Mariola; Veer, Cornelis Van't; Kummer, Markus P; Hornung, Veit; Kalff, Joerg C; de Jonge, Wouter J; Wehner, Sven

    2014-01-01

    Postoperative ileus (POI) is a common consequence of abdominal surgery that increases the risk of postoperative complications and morbidity. We investigated the cellular mechanisms and immune responses involved in the pathogenesis of POI. We studied a mouse model of POI in which intestinal manipulation leads to inflammation of the muscularis externa and disrupts motility. We used C57BL/6 (control) mice as well as mice deficient in Toll-like receptors (TLRs) and cytokine signaling components (TLR-2(-/-), TLR-4(-/-), TLR-2/4(-/-), MyD88(-/-), MyD88/TLR adaptor molecule 1(-/-), interleukin-1 receptor [IL-1R1](-/-), and interleukin (IL)-18(-/-) mice). Bone marrow transplantation experiments were performed to determine which cytokine receptors and cell types are involved in the pathogenesis of POI. Development of POI did not require TLRs 2, 4, or 9 or MyD88/TLR adaptor molecule 2 but did require MyD88, indicating a role for IL-1R1. IL-1R1(-/-) mice did not develop POI; however, mice deficient in IL-18, which also signals via MyD88, developed POI. Mice given injections of an IL-1 receptor antagonist (anakinra) or antibodies to deplete IL-1α and IL-1β before intestinal manipulation were protected from POI. Induction of POI activated the inflammasome in muscularis externa tissues of C57BL6 mice, and IL-1α and IL-1β were released in ex vivo organ bath cultures. In bone marrow transplantation experiments, the development of POI required activation of IL-1 receptor in nonhematopoietic cells. IL-1R1 was expressed by enteric glial cells in the myenteric plexus layer, and cultured primary enteric glia cells expressed IL-6 and the chemokine monocyte chemotactic protein 1 in response to IL-1β stimulation. Immunohistochemical analysis of human small bowel tissue samples confirmed expression of IL-1R1 in the ganglia of the myenteric plexus. IL-1 signaling, via IL-1R1 and MyD88, is required for development of POI after intestinal manipulation in mice. Agents that interfere with

  20. Association between GRB2/Sos and insulin receptor substrate 1 is not sufficient for activation of extracellular signal-regulated kinases by interleukin-4: implications for Ras activation by insulin.

    Science.gov (United States)

    Pruett, W; Yuan, Y; Rose, E; Batzer, A G; Harada, N; Skolnik, E Y

    1995-03-01

    Insulin receptor substrate 1 (IRS-1) mediates the activation of a variety of signaling pathways by the insulin and insulin-like growth factor 1 receptors by serving as a docking protein for signaling molecules with SH2 domains. We and others have shown that in response to insulin stimulation IRS-1 binds GRB2/Sos and have proposed that this interaction is important in mediating Ras activation by the insulin receptor. Recently, it has been shown that the interleukin (IL)-4 receptor also phosphorylates IRS-1 and an IRS-1-related molecule, 4PS. Unlike insulin, however, IL-4 fails to activate Ras, extracellular signal-regulated kinases (ERKs), or mitogen-activated protein kinases. We have reconstituted the IL-4 receptor into an insulin-responsive L6 myoblast cell line and have shown that IRS-1 is tyrosine phosphorylated to similar degrees in response to insulin and IL-4 stimulation in this cell line. In agreement with previous findings, IL-4 failed to activate the ERKs in this cell line or to stimulate DNA synthesis, whereas the same responses were activated by insulin. Surprisingly, IL-4's failure to activate ERKs was not due to a failure to stimulate the association of tyrosine-phosphorylated IRS-1 with GRB2/Sos; the amounts of GRB2/Sos associated with IRS-1 were similar in insulin- and IL-4-stimulated cells. Moreover, the amounts of phosphatidylinositol 3-kinase activity associated with IRS-1 were similar in insulin- and IL-4-stimulated cells. In contrast to insulin, however, IL-4 failed to induce tyrosine phosphorylation of Shc or association of Shc with GRB2. Thus, ERK activation correlates with Shc tyrosine phosphorylation and formation of an Shc/GRB2 complex. Thus, ERK activation correlates with Shc tyrosine phosphorylation and formation of an Shc/GRB2 complex. Previous studies have indicated that activation of ERks in this cell line is dependent upon Ras since a dominant-negative Ras (Asn-17) blocks ERK activation by insulin. Our findings, taken in the context

  1. The role of glucocorticoid receptor phosphorylation in Mcl-1 and NOXA gene expression

    Directory of Open Access Journals (Sweden)

    Demonacos Constantinos

    2010-02-01

    Full Text Available Abstract Background The cyclin-dependent kinase (CDK and mitogen-activated protein kinase (MAPK mediated phosphorylation of glucocorticoid receptor (GR exerts opposite effects on GR transcriptional activity and affects other posttranslational modifications within this protein. The major phosphorylation site of human GR targeted by MAPK family is the serine 226 and multiple kinase complexes phosphorylate receptor at the serine 211 residue. We hypothesize that GR posttranslational modifications are involved in the determination of the cellular fate in human lymphoblastic leukemia cells. We investigated whether UV signalling through alternative GR phosphorylation determined the cell type specificity of glucocorticoids (GCs mediated apoptosis. Results We have identified putative Glucocorticoid Response Elements (GREs within the promoter regulatory regions of the Bcl-2 family members NOXA and Mcl-1 indicating that they are direct GR transcriptional targets. These genes were differentially regulated in CEM-C7-14, CEM-C1-15 and A549 cells by glucocorticoids and JNK pathway. In addition, our results revealed that the S211 phosphorylation was dominant in CEM-C7-14, whereas the opposite was the case in CEM-C1-15 where prevalence of S226 GR phosphorylation was observed. Furthermore, multiple GR isoforms with cell line specific patterns were identified in CEM-C7-14 cells compared to CEM-C1-15 and A549 cell lines with the same antibodies. Conclusions GR phosphorylation status kinetics, and site specificity as well as isoform variability differ in CEM-C7-14, CEM-C1-15, and A549 cells. The positive or negative response to GCs induced apoptosis in these cell lines is a consequence of the variable equilibrium of NOXA and Mcl-1 gene expression potentially mediated by alternatively phosphorylated GR, as well as the balance of MAPK/CDK pathways controlling GR phosphorylation pattern. Our results provide molecular base and valuable knowledge for improving the GC

  2. Radiolabeling with fluorine-18 of a protein, interleukin-1 receptor antagonist

    Energy Technology Data Exchange (ETDEWEB)

    Prenant, C., E-mail: cprenant@cyclopharma.f [Wolfson Molecular Imaging Centre, University of Manchester, Manchester (United Kingdom); Cawthorne, C. [Academic Department of Radiation Oncology, Christie NHS Foundation Trust, Manchester (United Kingdom); Fairclough, M. [Wolfson Molecular Imaging Centre, University of Manchester, Manchester (United Kingdom); Rothwell, N.; Boutin, H. [Faculty of Life Sciences, University of Manchester, Manchester (United Kingdom)

    2010-09-15

    IL-1RA is a naturally occurring antagonist of the pro-inflammatory cytokine interleukin-1 (IL-1) with high therapeutic promise, but its pharmacokinetic remains poorly documented. In this report, we describe the radiolabeling of recombinant human interleukin-1 receptor antagonist (rhIL-1RA) with fluorine-18 to allow pharmacokinetic studies by positron emission tomography (PET). rhIL-1RA was labeled randomly by reductive alkylation of free amino groups (the {epsilon}-amino group of lysine residues or amino-terminal residues) using [{sup 18}F]fluoroacetaldehyde under mild reaction conditions. Radiosyntheses used a remotely controlled experimental rig within 100 min and the radiochemical yield was in the range 7.1-24.2% (decay corrected, based on seventeen syntheses). We showed that the produced [{sup 18}F]fluoroethyl-rhIL-1ra retained binding specificity by conducting an assay on rat brain sections, allowing its pharmakokinetic study using PET.

  3. Murine interleukin 1 receptor. Direct identification by ligand blotting and purification to homogeneity of an interleukin 1-binding glycoprotein

    International Nuclear Information System (INIS)

    Bird, T.A.; Gearing, A.J.; Saklatvala, J.

    1988-01-01

    Functional receptors (IL1-R) for the proinflammatory cytokine interleukin 1 (IL1) were solubilized from plasma membranes of the NOB-1 subclone of murine EL4 6.1 thymoma cells using the zwitterionic detergent 3[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate (CHAPS). Membrane extracts were subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to nitrocellulose membranes, and ligand blotted with 125 I-labeled recombinant human IL1 alpha in order to reveal proteins capable of specifically binding IL1. A single polydisperse polypeptide of Mr approximately equal to 80,000 was identified in this way, which bound IL1 alpha and IL1 beta with the same affinity as the IL1-R on intact NOB-1 cells (approximately equal to 10(-10) M). The IL1-binding polypeptide was only seen in membranes from IL1-R-bearing cells and did not react with interleukin 2, tumor necrosis factor alpha, or interferon. IL1-R was purified to apparent homogeneity from solubilized NOB-1 membranes by affinity chromatography on wheat germ agglutinin-Sepharose and IL1 alpha-Sepharose. Gel electrophoresis and silver staining of purified preparations revealed a single protein of Mr approximately equal to 80,000 which reacted positively in the ligand-blotting procedure and which we identify as the ligand-binding moiety of the murine IL1-R. Purified IL1-R exhibited the same affinity and specificity as the receptor on intact cells. The relationship of this protein to proteins identified by covalent cross-linking studies is discussed

  4. Deletion of interleukin 1 receptor-associated kinase 1 (Irak1) improves glucose tolerance primarily by increasing insulin sensitivity in skeletal muscle.

    Science.gov (United States)

    Sun, Xiao-Jian; Kim, Soohyun Park; Zhang, Dongming; Sun, Helen; Cao, Qi; Lu, Xin; Ying, Zhekang; Li, Liwu; Henry, Robert R; Ciaraldi, Theodore P; Taylor, Simeon I; Quon, Michael J

    2017-07-21

    Chronic inflammation may contribute to insulin resistance via molecular cross-talk between pathways for pro-inflammatory and insulin signaling. Interleukin 1 receptor-associated kinase 1 (IRAK-1) mediates pro-inflammatory signaling via IL-1 receptor/Toll-like receptors, which may contribute to insulin resistance, but this hypothesis is untested. Here, we used male Irak1 null (k/o) mice to investigate the metabolic role of IRAK-1. C57BL/6 wild-type (WT) and k/o mice had comparable body weights on low-fat and high-fat diets (LFD and HFD, respectively). After 12 weeks on LFD (but not HFD), k/o mice ( versus WT) had substantially improved glucose tolerance (assessed by the intraperitoneal glucose tolerance test (IPGTT)). As assessed with the hyperinsulinemic euglycemic glucose clamp technique, insulin sensitivity was 30% higher in the Irak1 k/o mice on chow diet, but the Irak1 deletion did not affect IPGTT outcomes in mice on HFD, suggesting that the deletion did not overcome the impact of obesity on glucose tolerance. Moreover, insulin-stimulated glucose-disposal rates were higher in the k/o mice, but we detected no significant difference in hepatic glucose production rates (± insulin infusion). Positron emission/computed tomography scans indicated higher insulin-stimulated glucose uptake in muscle, but not liver, in Irak1 k/o mice in vivo Moreover, insulin-stimulated phosphorylation of Akt was higher in muscle, but not in liver, from Irak1 k/o mice ex vivo In conclusion, Irak1 deletion improved muscle insulin sensitivity, with the effect being most apparent in LFD mice. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Noradrenaline, oxymetazoline and phorbol myristate acetate induce distinct functional actions and phosphorylation patterns of α1A-adrenergic receptors.

    Science.gov (United States)

    Alcántara-Hernández, Rocío; Hernández-Méndez, Aurelio; Romero-Ávila, M Teresa; Alfonzo-Méndez, Marco A; Pupo, André S; García-Sáinz, J Adolfo

    2017-12-01

    In LNCaP cells that stably express α 1A -adrenergic receptors, oxymetazoline increased intracellular calcium and receptor phosphorylation, however, this agonist was a weak partial agonist, as compared to noradrenaline, for calcium signaling. Interestingly, oxymetazoline-induced receptor internalization and desensitization displayed greater effects than those induced by noradrenaline. Phorbol myristate acetate induced modest receptor internalization and minimal desensitization. α 1A -Adrenergic receptor interaction with β-arrestins (colocalization/coimmunoprecipitation) was induced by noradrenaline and oxymetazoline and, to a lesser extent, by phorbol myristate acetate. Oxymetazoline was more potent and effective than noradrenaline in inducing ERK 1/2 phosphorylation. Mass spectrometric analysis of immunopurified α 1A -adrenergic receptors from cells treated with adrenergic agonists and the phorbol ester clearly showed that phosphorylated residues were present both at the third intracellular loop and at the carboxyl tail. Distinct phosphorylation patterns were observed under the different conditions. The phosphorylated residues were: a) Baseline and all treatments: T233; b) noradrenaline: S220, S227, S229, S246, S250, S389; c) oxymetazoline: S227, S246, S381, T384, S389; and d) phorbol myristate acetate: S246, S250, S258, S351, S352, S401, S402, S407, T411, S413, T451. Our novel data, describing the α 1A -AR phosphorylation sites, suggest that the observed different phosphorylation patterns may participate in defining adrenoceptor localization and action, under the different conditions examined. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Interleukin 1β, tumor necrosis factor-α and interleukin 6 decreas nuclear thyroid hormone receptor capacity in a liver cell line

    International Nuclear Information System (INIS)

    Wolf, M.; Hansen, N.; Greten, H.

    1994-01-01

    Many of the acute inflammatory responses in critical illness are mediated by tumor necrosis factor-α (TNTF-α), interleukin 1β (IL-1β) and interleukin 6 (IL-6). Furthermore, these cytokines are involved in mediating the characteristic changes of thyroid function during acute disease known as non-thyroidal illness. In the present studies the authors investigated in vitro whether TNF-α, IL-1β and IL-6 modify nuclear thyroid hormone receptor (TR) capacity and/or affinity. Regulation of TR synthesis was studied in the human hepatoma cell line Hep-G2. Subconfluent cells were incubated with recombinant cytokines in serum-free medium. Nuclear extracts were prepared by high-salt extraction of cell nuclei. Binding assays were performed with [ 125 I]-triiodothyronine; bound and free hormone were separated by filtration. Interleukin 1β decreased TR capacity in a dose-dependent manner. Compared with unstimulated cells, the TR capacity was reduced to 87.9 ± 3.9% after incubation with 0.1, 1.0 and 100 μg/l IL-1β, respectively. Interleukin 6 and TNF-α significantly reduced receptor capacity only at concentrations of 10μg/l or higher and the magnitude of the reduction was lower than with IL-1β. The TR capacity was reduced to 81.2 ± 2.3% and 83.2 ± 6.6% after stimulation with 10μg/l IL-6 or TNF-α, respectively. TR affinity was not altered significantly after stimulation with any of the cytokines. 44 refs., 4 figs

  7. Phenobarbital Meets Phosphorylation of Nuclear Receptors.

    Science.gov (United States)

    Negishi, Masahiko

    2017-05-01

    Phenobarbital was the first therapeutic drug to be characterized for its induction of hepatic drug metabolism. Essentially at the same time, cytochrome P450, an enzyme that metabolizes drugs, was discovered. After nearly 50 years of investigation, the molecular target of phenobarbital induction has now been delineated to phosphorylation at threonine 38 of the constitutive androstane receptor (NR1I3), a member of the nuclear receptor superfamily. Determining this mechanism has provided us with the molecular basis to understand drug induction of drug metabolism and disposition. Threonine 38 is conserved as a phosphorylation motif in the majority of both mouse and human nuclear receptors, providing us with an opportunity to integrate diverse functions of nuclear receptors. Here, I review the works and accomplishments of my laboratory at the National Institutes of Health National Institute of Environmental Health Sciences and the future research directions of where our study of the constitutive androstane receptor might take us. U.S. Government work not protected by U.S. copyright.

  8. The safety of interleukin-1 receptor antagonist (anakinra in the treatment of rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    L. Riente

    2011-09-01

    Full Text Available The safety profile of interleukin-1 receptor antagonist (anakinra has been studied with randomised, placebo-controlled trials involving 2932 patients affected by rheumatoid arthritis. The most frequently reported adverse events were represented by injection site reactions (71% and headache (13.6%. No statistically significant difference in the incidence of infections was observed among the patients treated with the interleukin-1 receptor antagonist and the patients receiving placebo. In particular, the incidence of serious infections was 1,8% in rheumatoid arthritis patients on anakinra therapy and 0,7% in patients on placebo. The reported serious infections consisted of pneumonia, cellulitis, bone and joint infections, bursitis. No case of opportunistic infections or tubercolosis was observed. The results of clinical studies suggest that anakinra is a new well-tolerated drug for the treatment of patients affected by rheumatoid arthritis.

  9. Structure-function similarities between a plant receptor-like kinase and the human interleukin-1 receptor-associated kinase-4.

    Science.gov (United States)

    Klaus-Heisen, Dörte; Nurisso, Alessandra; Pietraszewska-Bogiel, Anna; Mbengue, Malick; Camut, Sylvie; Timmers, Ton; Pichereaux, Carole; Rossignol, Michel; Gadella, Theodorus W J; Imberty, Anne; Lefebvre, Benoit; Cullimore, Julie V

    2011-04-01

    Phylogenetic analysis has previously shown that plant receptor-like kinases (RLKs) are monophyletic with respect to the kinase domain and share an evolutionary origin with the animal interleukin-1 receptor-associated kinase/Pelle-soluble kinases. The lysin motif domain-containing receptor-like kinase-3 (LYK3) of the legume Medicago truncatula shows 33% amino acid sequence identity with human IRAK-4 over the kinase domain. Using the structure of this animal kinase as a template, homology modeling revealed that the plant RLK contains structural features particular to this group of kinases, including the tyrosine gatekeeper and the N-terminal extension α-helix B. Functional analysis revealed the importance of these conserved features for kinase activity and suggests that kinase activity is essential for the biological role of LYK3 in the establishment of the root nodule nitrogen-fixing symbiosis with rhizobia bacteria. The kinase domain of LYK3 has dual serine/threonine and tyrosine specificity, and mass spectrometry analysis identified seven serine, eight threonine, and one tyrosine residue as autophosphorylation sites in vitro. Three activation loop serine/threonine residues are required for biological activity, and molecular dynamics simulations suggest that Thr-475 is the prototypical phosphorylated residue that interacts with the conserved arginine in the catalytic loop, whereas Ser-471 and Thr-472 may be secondary sites. A threonine in the juxtamembrane region and two threonines in the C-terminal lobe of the kinase domain are important for biological but not kinase activity. We present evidence that the structure-function similarities that we have identified between LYK3 and IRAK-4 may be more widely applicable to plant RLKs in general.

  10. Tumor-produced, active Interleukin-1 β regulates gene expression in carcinoma-associated fibroblasts

    International Nuclear Information System (INIS)

    Dudas, Jozsef; Fullar, Alexandra; Bitsche, Mario; Schartinger, Volker; Kovalszky, Ilona; Sprinzl, Georg Mathias; Riechelmann, Herbert

    2011-01-01

    Recently we described a co-culture model of periodontal ligament (PDL) fibroblasts and SCC-25 lingual squamous carcinoma cells, which resulted in conversion of normal fibroblasts into carcinoma-associated fibroblasts (CAFs), and in epithelial-mesenchymal transition (EMT) of SCC-25 cells. We have found a constitutive high interleukin-1β (IL1-β) expression in SCC-25 cells in normal and in co-cultured conditions. In our hypothesis a constitutive IL1-β expression in SCC-25 regulates gene expression in fibroblasts during co-culture. Co-cultures were performed between PDL fibroblasts and SCC-25 cells with and without dexamethasone (DEX) treatment; IL1-β processing was investigated in SCC-25 cells, tumor cells and PDL fibroblasts were treated with IL1-β. IL1-β signaling was investigated by western blot and immunocytochemistry. IL1-β-regulated genes were analyzed by real-time qPCR. SCC-25 cells produced 16 kD active IL1-β, its receptor was upregulated in PDL fibroblasts during co-culture, which induced phosphorylation of interleukin-1 receptor-associated kinase-1 (IRAK-1), and nuclear translocalization of NFκBα. Several genes, including interferon regulatory factor 1 (IRF1) interleukin-6 (IL-6) and prostaglandin-endoperoxide synthase 2 (COX-2) were induced in CAFs during co-culture. The most enhanced induction was found for IL-6 and COX-2. Treatment of PDL fibroblasts with IL1-β reproduced a time- and dose-dependent upregulation of IL1-receptor, IL-6 and COX-2. A further proof was achieved by DEX inhibition for IL1-β-stimulated IL-6 and COX-2 gene expression. Constitutive expression of IL1-β in the tumor cells leads to IL1-β-stimulated gene expression changes in tumor-associated fibroblasts, which are involved in tumor progression. -- Graphical abstract: SCC-25 cells produce active, processed IL1-β. PDL fibroblasts possess receptor for IL1-β, and its expression is increased 4.56-times in the presence of SCC-25 tumor cells. IL1receptor expression in

  11. Tumor-produced, active Interleukin-1 {beta} regulates gene expression in carcinoma-associated fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Dudas, Jozsef, E-mail: Jozsef.Dudas@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Fullar, Alexandra, E-mail: fullarsz@gmail.com [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); 1st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Ulloei ut 26, H-1085 Budapest (Hungary); Bitsche, Mario, E-mail: Mario.Bitsche@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Schartinger, Volker, E-mail: Volker.Schartinger@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Kovalszky, Ilona, E-mail: koval@korb1.sote.hu [1st Institute of Pathology and Experimental Cancer Research, Semmelweis University, Ulloei ut 26, H-1085 Budapest (Hungary); Sprinzl, Georg Mathias, E-mail: Georg.Sprinzl@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria); Riechelmann, Herbert, E-mail: Herbert.Riechelmann@i-med.ac.at [Department of Otorhinolaryngology, Medical University Innsbruck, Anichstrasse 35, A-6020 Innsbruck (Austria)

    2011-09-10

    Recently we described a co-culture model of periodontal ligament (PDL) fibroblasts and SCC-25 lingual squamous carcinoma cells, which resulted in conversion of normal fibroblasts into carcinoma-associated fibroblasts (CAFs), and in epithelial-mesenchymal transition (EMT) of SCC-25 cells. We have found a constitutive high interleukin-1{beta} (IL1-{beta}) expression in SCC-25 cells in normal and in co-cultured conditions. In our hypothesis a constitutive IL1-{beta} expression in SCC-25 regulates gene expression in fibroblasts during co-culture. Co-cultures were performed between PDL fibroblasts and SCC-25 cells with and without dexamethasone (DEX) treatment; IL1-{beta} processing was investigated in SCC-25 cells, tumor cells and PDL fibroblasts were treated with IL1-{beta}. IL1-{beta} signaling was investigated by western blot and immunocytochemistry. IL1-{beta}-regulated genes were analyzed by real-time qPCR. SCC-25 cells produced 16 kD active IL1-{beta}, its receptor was upregulated in PDL fibroblasts during co-culture, which induced phosphorylation of interleukin-1 receptor-associated kinase-1 (IRAK-1), and nuclear translocalization of NF{kappa}B{alpha}. Several genes, including interferon regulatory factor 1 (IRF1) interleukin-6 (IL-6) and prostaglandin-endoperoxide synthase 2 (COX-2) were induced in CAFs during co-culture. The most enhanced induction was found for IL-6 and COX-2. Treatment of PDL fibroblasts with IL1-{beta} reproduced a time- and dose-dependent upregulation of IL1-receptor, IL-6 and COX-2. A further proof was achieved by DEX inhibition for IL1-{beta}-stimulated IL-6 and COX-2 gene expression. Constitutive expression of IL1-{beta} in the tumor cells leads to IL1-{beta}-stimulated gene expression changes in tumor-associated fibroblasts, which are involved in tumor progression. -- Graphical abstract: SCC-25 cells produce active, processed IL1-{beta}. PDL fibroblasts possess receptor for IL1-{beta}, and its expression is increased 4.56-times in the

  12. Structural complementarity of Toll/interleukin-1 receptor domains in Toll-like receptors and the adaptors Mal and MyD88.

    Science.gov (United States)

    Dunne, Aisling; Ejdeback, Mikael; Ludidi, Phumzile L; O'Neill, Luke A J; Gay, Nicholas J

    2003-10-17

    The Toll/interleukin 1 receptor (TIR) domain is a region found in the cytoplasmic tails of members of the Toll-like receptor/interleukin-1 receptor superfamily. The domain is essential for signaling and is also found in the adaptor proteins Mal (MyD88 adaptor-like) and MyD88, which function to couple activation of the receptor to downstream signaling components. Experimental structures of two Toll/interleukin 1 receptor domains reveal a alpha-beta-fold similar to that of the bacterial chemotaxis protein CheY, and other evidence suggests that the adaptors can make heterotypic interactions with both the receptors and themselves. Here we show that the purified TIR domains of Mal and MyD88 can form stable heterodimers and also that Mal homodimers and oligomers are dissociated in the presence of ATP. To identify structural features that may contribute to the formation of signaling complexes, we produced models of the TIR domains from human Toll-like receptor 4 (TLR4), Mal, and MyD88. We found that although the overall fold is conserved the electrostatic surface potentials are quite distinct. Docking studies of the models suggest that Mal and MyD88 bind to different regions in TLRs 2 and 4, a finding consistent with a cooperative role of the two adaptors in signaling. Mal and MyD88 are predicted to interact at a third non-overlapping site, suggesting that the receptor and adaptors may form heterotetrameric complexes. The theoretical model of the interactions is supported by experimental data from glutathione S-transferase pull-downs and co-immunoprecipitations. Neither theoretical nor experimental data suggest a direct role for the conserved proline in the BB-loop in the association of TLR4, Mal, and MyD88. Finally we show a sequence relationship between the Drosophila protein Tube and Mal that may indicate a functional equivalence of these two adaptors in the Drosophila and vertebrate Toll pathways.

  13. Stress induces pain transition by potentiation of AMPA receptor phosphorylation.

    Science.gov (United States)

    Li, Changsheng; Yang, Ya; Liu, Sufang; Fang, Huaqiang; Zhang, Yong; Furmanski, Orion; Skinner, John; Xing, Ying; Johns, Roger A; Huganir, Richard L; Tao, Feng

    2014-10-08

    Chronic postsurgical pain is a serious issue in clinical practice. After surgery, patients experience ongoing pain or become sensitive to incident, normally nonpainful stimulation. The intensity and duration of postsurgical pain vary. However, it is unclear how the transition from acute to chronic pain occurs. Here we showed that social defeat stress enhanced plantar incision-induced AMPA receptor GluA1 phosphorylation at the Ser831 site in the spinal cord and greatly prolonged plantar incision-induced pain. Interestingly, targeted mutation of the GluA1 phosphorylation site Ser831 significantly inhibited stress-induced prolongation of incisional pain. In addition, stress hormones enhanced GluA1 phosphorylation and AMPA receptor-mediated electrical activity in the spinal cord. Subthreshold stimulation induced spinal long-term potentiation in GluA1 phosphomimetic mutant mice, but not in wild-type mice. Therefore, spinal AMPA receptor phosphorylation contributes to the mechanisms underlying stress-induced pain transition. Copyright © 2014 the authors 0270-6474/14/3413737-10$15.00/0.

  14. The role of GH receptor tyrosine phosphorylation in Stat5 activation

    DEFF Research Database (Denmark)

    Hansen, J A; Hansen, L H; Wang, X

    1997-01-01

    Stimulation of GH receptors leads to rapid activation of Jak2 kinase and subsequent tyrosine phosphorylation of the GH receptor. Three specific tyrosines located in the C-terminal domain of the GH receptor have been identified as being involved in GH-stimulated transcription of the Spi 2.1 promoter....... Mutated GH receptors lacking all but one of these three tyrosines are able to mediate a transcriptional response when transiently transfected into CHO cells together with a Spi 2.1 promoter/luciferase construct. Similarly, these GH receptors were found to be able to mediate activation of Stat5 DNA......-binding activity, whereas the GH receptor mutant lacking all intracellular tyrosines was not. Synthetic tyrosine phosphorylated peptides corresponding to the GH receptor sequence around the three tyrosines inhibited Stat5 DNA-binding activity while their non-phosphorylated counterparts were ineffective. Tyrosine...

  15. Phospholipase C-{delta}{sub 1} regulates interleukin-1{beta} and tumor necrosis factor-{alpha} mRNA expression

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Eric; Jakinovich, Paul; Bae, Aekyung [Department of Anesthesiology, Health Sciences Center L4 Rm 081, Stony Brook University, Stony Brook, NY 11794 (United States); Rebecchi, Mario, E-mail: Mario.rebecchi@SBUmed.org [Department of Anesthesiology, Health Sciences Center L4 Rm 081, Stony Brook University, Stony Brook, NY 11794 (United States)

    2012-10-01

    Phospholipase C-{delta}{sub 1} (PLC{delta}{sub 1}) is a widely expressed highly active PLC isoform, modulated by Ca{sup 2+} that appears to operate downstream from receptor signaling and has been linked to regulation of cytokine production. Here we investigated whether PLC{delta}{sub 1} modulated expression of the pro-inflammatory cytokines interleukin-1{beta} (IL-1{beta}), tumor necrosis factor-{alpha} (TNF-{alpha}) and interleukin-6 (IL-6) in rat C6 glioma cells. Expression of PLC{delta}{sub 1} was specifically suppressed by small interfering RNA (siRNA) and the effects on cytokine mRNA expression, stimulated by the Toll-like receptor (TLR) agonist, lipopolysaccharide (LPS), were examined. Real-time polymerase chain reaction (RT-PCR) results showed that PLC{delta}{sub 1} knockdown enhanced expression IL-1{beta} and tumor necrosis factor-{alpha} (TNF-{alpha}) mRNA by at least 100 fold after 4 h of LPS stimulation compared to control siRNA treatment. PLC{delta}{sub 1} knock down caused persistently high Nf{kappa}b levels at 4 h of LPS stimulation compared to control siRNA-treated cells. PLC{delta}{sub 1} knockdown was also associated with elevated nuclear levels of c-Jun after 30 min of LPS stimulation, but did not affect LPS-stimulated p38 or p42/44 MAPK phosphorylation, normally associated with TLR activation of cytokine gene expression; rather, enhanced protein kinase C (PKC) phosphorylation of cellular proteins was observed in the absence of LPS stimulation. An inhibitor of PKC, bisindolylmaleimide II (BIM), reversed phosphorylation, prevented elevation of nuclear c-Jun levels, and inhibited LPS-induced increases of IL-1{beta} and TNF-{alpha} mRNA's induced by PLC{delta}{sub 1} knockdown. Our results show that loss of PLC{delta}{sub 1} enhances PKC/c-Jun signaling and up-modulates pro-inflammatory cytokine gene transcription in concert with the TLR-stimulated p38MAPK/Nf{kappa}b pathway. Our findings are consistent with the idea that PLC{delta}{sub 1} is a

  16. Interleukin-1 antagonism in type 1 diabetes of recent onset

    DEFF Research Database (Denmark)

    Moran, Antoinette; Bundy, Brian; Becker, Dorothy J

    2013-01-01

    Innate immunity contributes to the pathogenesis of autoimmune diseases, such as type 1 diabetes, but until now no randomised, controlled trials of blockade of the key innate immune mediator interleukin-1 have been done. We aimed to assess whether canakinumab, a human monoclonal anti-interleukin-1...... antibody, or anakinra, a human interleukin-1 receptor antagonist, improved β-cell function in recent-onset type 1 diabetes....

  17. In vitro phosphorylation of insulin receptor substrate 1 by protein kinase C-zeta: functional analysis and identification of novel phosphorylation sites.

    Science.gov (United States)

    Sommerfeld, Mark R; Metzger, Sabine; Stosik, Magdalene; Tennagels, Norbert; Eckel, Jürgen

    2004-05-18

    Protein kinase C-zeta (PKC-zeta) participates both in downstream insulin signaling and in the negative feedback control of insulin action. Here we used an in vitro approach to identify PKC-zeta phosphorylation sites within insulin receptor substrate 1 (IRS-1) and to characterize the functional implications. A recombinant IRS-1 fragment (rIRS-1(449)(-)(664)) containing major tyrosine motifs for interaction with phosphatidylinositol (PI) 3-kinase strongly associated to the p85alpha subunit of PI 3-kinase after Tyr phosphorylation by the insulin receptor. Phosphorylation of rIRS-1(449)(-)(664) by PKC-zeta induced a prominent inhibition of this process with a mixture of classical PKC isoforms being less effective. Both PKC-zeta and the classical isoforms phosphorylated rIRS-1(449)(-)(664) on Ser(612). However, modification of this residue did not reduce the affinity of p85alpha binding to pTyr-containing peptides (amino acids 605-615 of rat IRS-1), as determined by surface plasmon resonance. rIRS-1(449)(-)(664) was then phosphorylated by PKC-zeta using [(32)P]ATP and subjected to tryptic phosphopeptide mapping based on two-dimensional HPLC coupled to mass spectrometry. Ser(498) and Ser(570) were identified as novel phosphoserine sites targeted by PKC-zeta. Both sites were additionally confirmed by phosphopeptide mapping of the corresponding Ser --> Ala mutants of rIRS-1(449)(-)(664). Ser(570) was specifically targeted by PKC-zeta, as shown by immunoblotting with a phosphospecific antiserum against Ser(570) of IRS-1. Binding of p85alpha to the S570A mutant was less susceptible to inhibition by PKC-zeta, when compared to the S612A mutant. In conclusion, our in vitro data demonstrate a strong inhibitory action of PKC-zeta at the level of IRS-1/PI 3-kinase interaction involving multiple serine phosphorylation sites. Whereas Ser(612) appears not to participate in the negative control of insulin signaling, Ser(570) may at least partly contribute to this process.

  18. Measurement of biologically active interleukin-1 by a soluble receptor binding assay

    International Nuclear Information System (INIS)

    Riske, F.; Chizzonite, R.; Nunes, P.; Stern, A.S.

    1990-01-01

    A soluble receptor binding assay has been developed for measuring human interleukin-1 alpha (IL-1 alpha), human IL-1 beta, and mouse IL-1 alpha. The assay is based on a competition between unlabeled IL-1 and 125I-labeled mouse recombinant IL-1 alpha for binding to soluble IL-1 receptor prepared from mouse EL-4 cells. The assay measures only biologically active IL-1 folded in its native conformation. The ratio of human IL-1 alpha to human IL-1 beta can be measured in the same sample by a pretreatment step which removes human IL-1 beta from samples prior to assay. This technique has been used to monitor the purification of recombinant IL-1, and may be utilized to specifically and accurately measure bioactive IL-1 in human serum and cell culture supernatants

  19. Kinome analysis of receptor-induced phosphorylation in human natural killer cells.

    Directory of Open Access Journals (Sweden)

    Sebastian König

    Full Text Available BACKGROUND: Natural killer (NK cells contribute to the defense against infected and transformed cells through the engagement of multiple germline-encoded activation receptors. Stimulation of the Fc receptor CD16 alone is sufficient for NK cell activation, whereas other receptors, such as 2B4 (CD244 and DNAM-1 (CD226, act synergistically. After receptor engagement, protein kinases play a major role in signaling networks controlling NK cell effector functions. However, it has not been characterized systematically which of all kinases encoded by the human genome (kinome are involved in NK cell activation. RESULTS: A kinase-selective phosphoproteome approach enabled the determination of 188 kinases expressed in human NK cells. Crosslinking of CD16 as well as 2B4 and DNAM-1 revealed a total of 313 distinct kinase phosphorylation sites on 109 different kinases. Phosphorylation sites on 21 kinases were similarly regulated after engagement of either CD16 or co-engagement of 2B4 and DNAM-1. Among those, increased phosphorylation of FYN, KCC2G (CAMK2, FES, and AAK1, as well as the reduced phosphorylation of MARK2, were reproducibly observed both after engagement of CD16 and co-engagement of 2B4 and DNAM-1. Notably, only one phosphorylation on PAK4 was differentally regulated. CONCLUSIONS: The present study has identified a significant portion of the NK cell kinome and defined novel phosphorylation sites in primary lymphocytes. Regulated phosphorylations observed in the early phase of NK cell activation imply these kinases are involved in NK cell signaling. Taken together, this study suggests a largely shared signaling pathway downstream of distinct activation receptors and constitutes a valuable resource for further elucidating the regulation of NK cell effector responses.

  20. Distinct Phosphorylation Clusters Determine the Signaling Outcome of Free Fatty Acid Receptor 4/G Protein-Coupled Receptor 120

    DEFF Research Database (Denmark)

    Prihandoko, Rudi; Alvarez-Curto, Elisa; Hudson, Brian D

    2016-01-01

    of these phosphoacceptor sites to alanine completely prevented phosphorylation of mFFA4 but did not limit receptor coupling to extracellular signal regulated protein kinase 1 and 2 (ERK1/2) activation. Rather, an inhibitor of Gq/11proteins completely prevented receptor signaling to ERK1/2. By contrast, the recruitment...... activation. These unique observations define differential effects on signaling mediated by phosphorylation at distinct locations. This hallmark feature supports the possibility that the signaling outcome of mFFA4 activation can be determined by the pattern of phosphorylation (phosphorylation barcode...

  1. Activation of JAK3, but not JAK1, is critical to interleukin-4 (IL4) stimulated proliferation and requires a membrane-proximal region of IL4 receptor alpha.

    Science.gov (United States)

    Malabarba, M G; Kirken, R A; Rui, H; Koettnitz, K; Kawamura, M; O'Shea, J J; Kalthoff, F S; Farrar, W L

    1995-04-21

    The tyrosine kinases JAK1 and JAK3 have been shown to undergo tyrosine phosphorylation in response to interleukin-2 (IL), IL4, IL7, and IL9, cytokines which share the common IL2 receptor gamma-chain (IL2R gamma), and evidence has been found for a preferential coupling of JAK3 to IL2R gamma and JAK1 to IL2R beta. Here we show, using human premyeloid TF-1 cells, that IL4 stimulates JAK3 to a larger extent than JAK1, based upon three different evaluation criteria. These include a more vigorous tyrosine phosphorylation of JAK3 as measured by anti-phosphotyrosine immunoblotting, a more marked activation of JAK3 as determined by in vitro tyrosine kinase assays and a more manifest presence of JAK3 in activated IL4-receptor complexes. These observations suggest that IL4 receptor signal transduction does not depend on equimolar heterodimerization of JAK1 and JAK3 following IL4-induced heterodimerization of IL4R alpha and IL2R gamma. Indeed, when human IL4R alpha was stably expressed in mouse BA/F3 cells, robust IL4-induced proliferation and JAK3 activation occurred without detectable involvement of JAK1, JAK2, or TYK2. The present study suggests that JAK1 plays a subordinate role in IL4 receptor signaling, and that in certain cells exclusive JAK3 activation may mediate IL4-induced cell growth. Moreover, mutational analysis of human IL4R alpha showed that a membrane-proximal cytoplasmic region was critical for JAK3 activation, while the I4R motif was not, which is compatible with a role of JAK3 upstream of the recruitment of the insulin receptor substrate-1/4PS signaling proteins by IL4 receptors.

  2. An unusual protein kinase phosphorylates the chemotactic receptor of Dictystelium discoideum

    International Nuclear Information System (INIS)

    Meier, K.; Klein, C.

    1988-01-01

    The authors report the cAMP-dependent phosphorylation of the chemotactic receptor of Dictyostelium discoideum in partially purified plasma membranes. The protein kinase responsible for receptor phosphorylation is associated with this fraction and preferentially phosphorylates the ligand-occupied form of the receptor. 8-Azido[ 32 P]cAMP labeling of the cell surface has shown that the cAMP receptor exists in two forms. A 45-kDa protein is predominant on unstimulated cells. cAMP stimulation results in an increased receptor phosphorylation such that the receptor migrates on NaDodSO 4 /PAGE as a 47-kDa protein. Phosphorylation of the chemotactic receptor is not detected in membrane preparations unless cAMP is added to the incubation mixture. Only under those conditions is the phosphorylated 47-kDa form observed. The requirement for cAMP reflects the fact that the kinase involved preferentially uses the ligand-occupied receptor as a substrate. In vitro phosphorylation of the receptor does not involve tyrosine residues. The enzyme does not appear to be a cAMP- or cGMP-dependent protein kinase nor is it sensitive to guanine nucleotides, Ca 2+ /calmodulin, Ca 2+ /phospholipid, or EGTA. Similarities with the β-adrenergic receptor protein kinase are discussed

  3. Prevention of cold-associated acute inflammation in familial cold autoinflammatory syndrome by interleukin-1 receptor antagonist.

    Science.gov (United States)

    Hoffman, Hal M; Rosengren, Sanna; Boyle, David L; Cho, Jae Y; Nayar, Jyothi; Mueller, James L; Anderson, Justin P; Wanderer, Alan A; Firestein, Gary S

    Familial cold autoinflammatory syndrome (FCAS) is an autosomal dominant disorder characterised by recurrent episodes of rash, arthralgia, and fever after cold exposure. The genetic basis of this disease has been elucidated. Cryopyrin, the protein that is altered in FCAS, is one of the adaptor proteins that activate caspase 1, resulting in release of interleukin 1. An experimental cold challenge protocol was developed to study the acute inflammatory mechanisms occurring after a general cold exposure in FCAS patients and to investigate the effects of pretreatment with an antagonist of interleukin 1 receptor (IL-1Ra). ELISA, real-time PCR, and immunohistochemistry were used to measure cytokine responses. After cold challenge, untreated patients with FCAS developed rash, fever, and arthralgias within 1-4 h. Significant increases in serum concentrations of interleukin 6 and white-blood-cell counts were seen 4-8 h after cold challenge. Serum concentrations of interleukin 1 and cytokine mRNA in peripheral-blood leucocytes were not raised, but amounts of interleukin 1 protein and mRNA were high in affected skin. IL-1Ra administered before cold challenge blocked symptoms and increases in white-blood-cell counts and serum interleukin 6. The ability of IL-1Ra to prevent the clinical features and haematological and biochemical changes in patients with FCAS indicates a central role for interleukin 1beta in this disorder. Involvement of cryopyrin in activation of caspase 1 and NF-kappaB signalling suggests that it might have a role in many chronic inflammatory diseases. These findings support a new therapy for a disorder with no previously known acceptable treatment. They also offer insights into the role of interleukin 1beta in more common inflammatory diseases.

  4. Very late-onset group B Streptococcus meningitis, sepsis, and systemic shigellosis due to interleukin-1 receptor-associated kinase-4 deficiency.

    Science.gov (United States)

    Krause, Jens C; Ghandil, Pegah; Chrabieh, Maya; Casanova, Jean-Laurent; Picard, Capucine; Puel, Anne; Creech, C Buddy

    2009-11-01

    We describe a child with very late-onset group B Streptococcus sepsis and meningitis, systemic shigellosis, and chronic osteomyelitis. Peripheral blood cells obtained from the patient and her brother did not respond to stimulation with either interleukin-1beta or lipopolysaccharide. Sequencing of the interleukin-1 receptor-associated kinase-4 gene revealed 2 novel mutations.

  5. Phosphorylation of the Transient Receptor Potential Ankyrin 1 by Cyclin-dependent Kinase 5 affects Chemo-nociception

    OpenAIRE

    Hall, Bradford E.; Prochazkova, Michaela; Sapio, Matthew R.; Minetos, Paul; Kurochkina, Natalya; Binukumar, B. K.; Amin, Niranjana D.; Terse, Anita; Joseph, John; Raithel, Stephen J.; Mannes, Andrew J.; Pant, Harish C.; Chung, Man-Kyo; Iadarola, Michael J.; Kulkarni, Ashok B.

    2018-01-01

    Cyclin-dependent kinase 5 (Cdk5) is a key neuronal kinase that is upregulated during inflammation, and can subsequently modulate sensitivity to nociceptive stimuli. We conducted an in silico screen for Cdk5 phosphorylation sites within proteins whose expression was enriched in nociceptors and identified the chemo-responsive ion channel Transient Receptor Potential Ankyrin 1 (TRPA1) as a possible Cdk5 substrate. Immunoprecipitated full length TRPA1 was shown to be phosphorylated by Cdk5 and th...

  6. Curcumin blocks interleukin (IL)-2 signaling in T-lymphocytes by inhibiting IL-2 synthesis, CD25 expression, and IL-2 receptor signaling

    International Nuclear Information System (INIS)

    Forward, Nicholas A.; Conrad, David M.; Power Coombs, Melanie R.; Doucette, Carolyn D.; Furlong, Suzanne J.; Lin, Tong-Jun; Hoskin, David W.

    2011-01-01

    Highlights: → Curcumin inhibits CD4 + T-lymphocyte proliferation. → Curcumin inhibits interleukin-2 (IL-2) synthesis and CD25 expression by CD4 + T-lymphocytes. → Curcumin interferes with IL-2 receptor signaling by inhibiting JAK3 and STAT5 phosphorylation. → IL-2-dependent regulatory T-lymphocyte function and Foxp3 expression is downregulated by curcumin. -- Abstract: Curcumin (diferulomethane) is the principal curcuminoid in the spice tumeric and a potent inhibitor of activation-induced T-lymphocyte proliferation; however, the molecular basis of this immunosuppressive effect has not been well studied. Here we show that micromolar concentrations of curcumin inhibited DNA synthesis by mouse CD4 + T-lymphocytes, as well as interleukin-2 (IL-2) and CD25 (α chain of the high affinity IL-2 receptor) expression in response to antibody-mediated cross-linking of CD3 and CD28. Curcumin acted downstream of protein kinase C activation and intracellular Ca 2+ release to inhibit IκB phosphorylation, which is required for nuclear translocation of the transcription factor NFκB. In addition, IL-2-dependent DNA synthesis by mouse CTLL-2 cells, but not constitutive CD25 expression, was impaired in the presence of curcumin, which demonstrated an inhibitory effect on IL-2 receptor (IL-2R) signaling. IL-2-induced phosphorylation of STAT5A and JAK3, but not JAK1, was diminished in the presence of curcumin, indicating inhibition of critical proximal events in IL-2R signaling. In line with the inhibitory action of curcumin on IL-2R signaling, pretreatment of CD4 + CD25 + regulatory T-cells with curcumin downregulated suppressor function, as well as forkhead box p3 (Foxp3) expression. We conclude that curcumin inhibits IL-2 signaling by reducing available IL-2 and high affinity IL-2R, as well as interfering with IL-2R signaling.

  7. Emerging Role of Interleukin-1 in Cardiovascular Diseases

    Czech Academy of Sciences Publication Activity Database

    Vicenová, B.; Vopálenský, D.; Burýšek, L.; Pospíšek, Martin

    2009-01-01

    Roč. 58, č. 4 (2009), s. 481-498 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) 1M06014 Keywords : interleukin-1 * interleukin-1 receptor antagonist protein * signal pathways * cardiovascular diseases Subject RIV: ED - Physiology Impact factor: 1.430, year: 2009 http://www.biomed.cas.cz/physiolres/pdf/58/58_481.pdf

  8. A computational study of the chemokine receptor CXCR1 bound with interleukin-8

    Science.gov (United States)

    Wang, Yang; Severin Lupala, Cecylia; Wang, Ting; Li, Xuanxuan; Yun, Ji-Hye; Park, Jae-hyun; Jin, Zeyu; Lee, Weontae; Tan, Leihan; Liu, Haiguang

    2018-03-01

    CXCR1 is a G-protein coupled receptor, transducing signals from chemokines, in particular the interleukin-8 (IL8) molecules. This study combines homology modeling and molecular dynamics simulation methods to study the structure of CXCR1-IL8 complex. By using CXCR4-vMIP-II crystallography structure as the homologous template, CXCR1-IL8 complex structure was constructed, and then refined using all-atom molecular dynamics simulations. Through extensive simulations, CXCR1-IL8 binding poses were investigated in detail. Furthermore, the role of the N-terminal of CXCR1 receptor was studied by comparing four complex models differing in the N-terminal sequences. The results indicate that the receptor N-terminal affects the binding of IL8 significantly. With a shorter N-terminal domain, the binding of IL8 to CXCR1 becomes unstable. The homology modeling and simulations also reveal the key receptor-ligand residues involved in the electrostatic interactions known to be vital for complex formation. Project supported by the National Natural Science Foundation of China (Grant Nos. 11575021, U1530401, and U1430237) and the National Research Foundation of Korea (Grant Nos. NRF-2017R1A2B2008483 and NRF-2016R1A6A3A04010213).

  9. Changes in haematological indices following local application of interleukin-1 receptor antagonist protein after tenotomy in rabbits

    Directory of Open Access Journals (Sweden)

    Marko Pecin

    2017-01-01

    Full Text Available Interleukin-1 (IL-1 is the most important cytokine in the inflammation cascade activation in all tissues and is present in acute and chronic phases of inflammation. By blocking IL-1 binding to target cells, numerous inflammation processes are prevented. The use of autologous conditioned serum rich with IL-1 receptor antagonist protein (IL-1Ra is a novel treatment method of tendon inflammation in domestic animals and humans. Injections of autologous conditioned serum (ACS have demonstrated clinical efficacy and safety in animal models and humans in the treatment of osteoarthritis, disc prolapse and muscles and tendons injuries with low side effect. Neutropaenia, reduced white blood cell count, and infections or local irritations are described as side effects of IL-1 antagonist use in humans. Therefore, a study of blood changes in rabbits after local administration of IL-1Ra in the Achilles tendon tissue after iatrogenic inflammation was conducted. Interleukin-1 receptor antagonist protein was used to prevent and reduce tendon inflammation after longitudinal tenotomy. The study was done on 26 white Californian rabbits, divided into two equal groups consisting of 13 animals each; the experimental interleukin-1 receptor antagonist protein (irap group, and the control group. In the irap group, autologous serum rich with IL-1Ra was used (Orthokine®vet irap, Alfa-Arthro, Croatia. Differences between two groups were considered significant as changes in the blood for certain blood elements at P < 0.01. The P value was P = 0.0153 for the white blood cells, P = 0.00153 for neutrophils, P = 0.00017 and for platelets. In the control group, an increased platelet count was noticed in 70% of blood samples and a decreased neutrophil count was found in all of the irap group samples at the end of the study in comparison to the initial blood count prior to application.

  10. A single tyrosine of the interleukin-9 (IL-9) receptor is required for STAT activation, antiapoptotic activity, and growth regulation by IL-9.

    Science.gov (United States)

    Demoulin, J B; Uyttenhove, C; Van Roost, E; DeLestré, B; Donckers, D; Van Snick, J; Renauld, J C

    1996-09-01

    Interleukin-9 (IL-9), a T-cell-derived cytokine, interacts with a specific receptor associated with the IL-2 receptor gamma chain. In this report, we analyze the functional domains of the human IL-9 receptor transfected into mouse lymphoid cell lines. Three different functions were examined: growth stimulation in factor-dependent pro-B Ba/F3 cells, protection against dexamethasone-induced apoptosis, and Ly-6A2 induction in BW5147 lymphoma cells. The results indicated that a single tyrosine, at position 116 in the cytoplasmic domain, was required for all three activities. In addition, we observed that human IL-9 reduced the proliferation rate of transfected BW5147 cells, an effect also dependent on the same tyrosine. This amino acid was necessary for IL-9-mediated tyrosine phosphorylation of the receptor and for STAT activation but not for IRS-2/4PS activation or for JAK1 phosphorylation, which depended on a domain closer to the plasma membrane. We also showed that JAK1 was constitutively associated with the IL-9 receptor. Activated STAT complexes induced by IL-9 were found to contain STAT1, STAT3, and STAT5 transcription factors. Moreover, sequence homologies between human IL-9 receptor tyrosine 116 and tyrosines (of other receptors activating STAT3 and STAT5 were observed. Taken together, these data indicate that a single tyrosine of the IL-9 receptor, required for activation of three different STAT proteins, is necessary for distinct activities of this cytokine, including proliferative responses.

  11. Gemfibrozil, a lipid-lowering drug, upregulates interleukin-1 receptor antagonist in mouse cortical neurons: Implications for neuronal self-defense

    Science.gov (United States)

    Corbett, Grant T.; Roy, Avik; Pahan, Kalipada

    2012-01-01

    Chronic inflammation is becoming a hallmark of several neurodegenerative disorders and accordingly, interleukin-1 beta (IL-1β), a proinflammatory cytokine, is implicated in the pathogenesis of neurodegenerative diseases. While IL-1β binds to its high-affinity receptor, interleukin-1 receptor (IL-1R), and upregulates proinflammatory signaling pathways, interleukin-1 receptor antagonist (IL-1Ra) adheres to the same receptor and inhibits proinflammatory cell signaling. Therefore, upregulation of IL-1Ra is considered important in attenuating inflammation. The present study underlines a novel application of gemfibrozil, an FDA-approved lipid-lowering drug, in increasing the expression of IL-1Ra in primary mouse and human neurons. Gemfibrozil alone induced an early and pronounced increase in the expression of IL-1Ra in primary mouse cortical neurons. Activation of type IA p110α phosphatidylinositol 3-kinase (PI3-K) and Akt by gemfibrozil and abrogation of gemfibrozil-induced upregulation of IL-1Ra by inhibitors of PI3-K and Akt indicate a role of the PI3-K – Akt pathway in the upregulation of IL-1Ra. Gemfibrozil also induced the activation of cAMP response element-binding (CREB) via the PI3-K – Akt pathway and siRNA attenuation of CREB abolished the gemfibrozil-mediated increase in IL-1Ra. Furthermore, gemfibrozil was able to protect neurons from IL-1β insult. However, siRNA knockdown of neuronal IL-1Ra abrogated the protective effect of gemfibrozil against IL-1β suggesting that this drug increases the defense mechanism of cortical neurons via upregulation of IL-1Ra. Together, these results highlight the importance of the PI3-K – Akt – CREB pathway in mediating gemfibrozil-induced upregulation of IL-1Ra in neurons and suggest gemfibrozil as a possible therapeutic treatment for propagating neuronal self defense in neuroinflammatory and neurodegenerative disorders. PMID:22706077

  12. Interleukin-1 receptors in mouse brain: Characterization and neuronal localization

    International Nuclear Information System (INIS)

    Takao, T.; Tracey, D.E.; Mitchell, W.M.; De Souza, E.B.

    1990-01-01

    The cytokine interleukin-1 (IL-1) has a variety of effects in brain, including induction of fever, alteration of slow wave sleep, and alteration of neuroendocrine activity. To examine the potential sites of action of IL-1 in brain, we used iodine-125-labeled recombinant human interleukin-1 [( 125I]IL-1) to identify and characterize IL-1 receptors in crude membrane preparations of mouse (C57BL/6) hippocampus and to study the distribution of IL-1-binding sites in brain using autoradiography. In preliminary homogenate binding and autoradiographic studies, [125I]IL-1 alpha showed significantly higher specific binding than [125I]IL-1 beta. Thus, [125I]IL-1 alpha was used in all subsequent assays. The binding of [125I]IL-1 alpha was linear over a broad range of membrane protein concentrations, saturable, reversible, and of high affinity, with an equilibrium dissociation constant value of 114 +/- 35 pM and a maximum number of binding sites of 2.5 +/- 0.4 fmol/mg protein. In competition studies, recombinant human IL-1 alpha, recombinant human IL-1 beta, and a weak IL-1 beta analog. IL-1 beta +, inhibited [125I]IL-1 alpha binding to mouse hippocampus in parallel with their relative bioactivities in the T-cell comitogenesis assay, with inhibitory binding affinity constants of 55 +/- 18, 76 +/- 20, and 2940 +/- 742 pM, respectively; rat/human CRF and human tumor necrosis factor showed no effect on [125I]IL-1 alpha binding. Autoradiographic localization studies revealed very low densities of [125I]IL-1 alpha-binding sites throughout the brain, with highest densities present in the molecular and granular layers of the dentate gyrus of the hippocampus and in the choroid plexus. Quinolinic acid lesion studies demonstrated that the [125I]IL-1 alpha-binding sites in the hippocampus were localized to intrinsic neurons

  13. Cardiometabolic effects of genetic upregulation of the interleukin 1 receptor antagonist

    DEFF Research Database (Denmark)

    2015-01-01

    BACKGROUND: To investigate potential cardiovascular and other effects of long-term pharmacological interleukin 1 (IL-1) inhibition, we studied genetic variants that produce inhibition of IL-1, a master regulator of inflammation. METHODS: We created a genetic score combining the effects of alleles...... of two common variants (rs6743376 and rs1542176) that are located upstream of IL1RN, the gene encoding the IL-1 receptor antagonist (IL-1Ra; an endogenous inhibitor of both IL-1α and IL-1β); both alleles increase soluble IL-1Ra protein concentration. We compared effects on inflammation biomarkers...... of this genetic score with those of anakinra, the recombinant form of IL-1Ra, which has previously been studied in randomised trials of rheumatoid arthritis and other inflammatory disorders. In primary analyses, we investigated the score in relation to rheumatoid arthritis and four cardiometabolic diseases (type...

  14. C1qTNF-related protein 1 improve insulin resistance by reducing phosphorylation of serine 1101 in insulin receptor substrate 1.

    Science.gov (United States)

    Xin, Yaping; Zhang, Dongming; Fu, Yanqin; Wang, Chongxian; Li, Qingju; Tian, Chenguang; Zhang, Suhe; Lyu, Xiaodong

    2017-08-30

    C1qTNF-related protein 1 (CTRP1) is independently associated with type 2 diabetes. However, the relationship between CTRP1 and insulin resistance is still not established. This study aimed to explore the role of CTRP1 under the situation of insulin resistance in adipose tissue. Plasma CTRP1 level was investigated in type 2 diabetic subjects (n = 35) and non-diabetic subjects (n = 35). The relationship between CTRP1 and phosphorylation of multi insulin receptor substrate 1 (IRS-1) serine (Ser) sites was further explored. Our data showed that Plasma CTRP1 was higher and negative correlation with insulin resistance in diabetic subjects (r = -0.283, p = 0.018). Glucose utilisation test revealed that the glucose utilisation rate of mature adipocytes was improved by CTRP1 in the presence of insulin. CTRP1 was not only related to IRS-1 protein, but also negatively correlated with IRS-1 Ser1101 phosphorylation (r = -0.398, p = 0.031). Furthermore, Phosphorylation levels of IRS-1 Ser1101 were significantly lower after incubation with 40 ng/mL CTRP1 in mature adipocytes than those with no intervention (p insulin resistance by reducing the phosphorylation of IRS-1 Ser1101, induced in the situation of insulin resistance as a feedback adipokine.

  15. [Interleukin-37 induces apoptosis and autophagy of SMMC-7721 cells by inhibiting phosphorylation of mTOR].

    Science.gov (United States)

    Li, Tingting; Zhu, Di; Mou, Tong; Guo, Zhen; Pu, Junliang; Wu, Zhongjun

    2017-04-01

    Objective To investigate the underlying mechanism by which interleukin-37 (IL-37) induces the apoptosis and autophagy in SMMC-7721 cells. Methods SMMC-7721 cells were incubated in vitro and divided into two groups, IL-37 treated group and control group. The cells were treated with (50, 100, 200) ng/mL of recombinant human interleukin-37 (rhIL-37). CCK-8 assay was used to detect the cell proliferation of SMMC-7721 cells. Cell apoptosis was measured by flow cytometry. Western blot analysis was performed to examine the expressions of apoptosis-related proteins, Bax, Bcl-2, and autophagy related proteins, microtubule-associated proteins 1 light chain 3 (LC3), beclin 1 and mammalian target of rapamycin (mTOR). Transmission electron microscopy (TEM) was used to observe the ultrastructures of autophagosomes. Results The rhIL-37 inhibited the proliferation of hepatocellular carcinoma SMMC-7721 cells. It induced the apoptosis and autophagy in SMMC-7721 cells. In the IL-37 treated group, the levels of Bax, LC3 and beclin 1 increased but Bcl-2 decreased. The phosphorylation of mTOR was inhibited in the IL-37 treated group. Autophagosome was obvious in the IL-37 treated group. Conclusion IL-37 induces the apoptosis and autophagy in SMMC-7721 cells, which may be related to the phosphorylation of mTOR.

  16. The transmembrane domain of the p75 neurotrophin receptor stimulates phosphorylation of the TrkB tyrosine kinase receptor.

    Science.gov (United States)

    Saadipour, Khalil; MacLean, Michael; Pirkle, Sean; Ali, Solav; Lopez-Redondo, Maria-Luisa; Stokes, David L; Chao, Moses V

    2017-10-06

    The function of protein products generated from intramembraneous cleavage by the γ-secretase complex is not well defined. The γ-secretase complex is responsible for the cleavage of several transmembrane proteins, most notably the amyloid precursor protein that results in Aβ, a transmembrane (TM) peptide. Another protein that undergoes very similar γ-secretase cleavage is the p75 neurotrophin receptor. However, the fate of the cleaved p75 TM domain is unknown. p75 neurotrophin receptor is highly expressed during early neuronal development and regulates survival and process formation of neurons. Here, we report that the p75 TM can stimulate the phosphorylation of TrkB (tyrosine kinase receptor B). In vitro phosphorylation experiments indicated that a peptide representing p75 TM increases TrkB phosphorylation in a dose- and time-dependent manner. Moreover, mutagenesis analyses revealed that a valine residue at position 264 in the rat p75 neurotrophin receptor is necessary for the ability of p75 TM to induce TrkB phosphorylation. Because this residue is just before the γ-secretase cleavage site, we then investigated whether the p75(αγ) peptide, which is a product of both α- and γ-cleavage events, could also induce TrkB phosphorylation. Experiments using TM domains from other receptors, EGFR and FGFR1, failed to stimulate TrkB phosphorylation. Co-immunoprecipitation and biochemical fractionation data suggested that p75 TM stimulates TrkB phosphorylation at the cell membrane. Altogether, our results suggest that TrkB activation by p75(αγ) peptide may be enhanced in situations where the levels of the p75 receptor are increased, such as during brain injury, Alzheimer's disease, and epilepsy. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Curcumin blocks interleukin (IL)-2 signaling in T-lymphocytes by inhibiting IL-2 synthesis, CD25 expression, and IL-2 receptor signaling

    Energy Technology Data Exchange (ETDEWEB)

    Forward, Nicholas A.; Conrad, David M. [Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia (Canada); Power Coombs, Melanie R.; Doucette, Carolyn D. [Department of Pathology, Dalhousie University, Halifax, Nova Scotia (Canada); Furlong, Suzanne J. [Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia (Canada); Lin, Tong-Jun [Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia (Canada); Department of Pediatrics, Dalhousie University, Halifax, Nova Scotia (Canada); Hoskin, David W., E-mail: d.w.hoskin@dal.ca [Department of Microbiology and Immunology, Dalhousie University, Halifax, Nova Scotia (Canada); Department of Pathology, Dalhousie University, Halifax, Nova Scotia (Canada); Department of Surgery, Dalhousie University, Halifax, Nova Scotia (Canada)

    2011-04-22

    Highlights: {yields} Curcumin inhibits CD4{sup +} T-lymphocyte proliferation. {yields} Curcumin inhibits interleukin-2 (IL-2) synthesis and CD25 expression by CD4{sup +} T-lymphocytes. {yields} Curcumin interferes with IL-2 receptor signaling by inhibiting JAK3 and STAT5 phosphorylation. {yields} IL-2-dependent regulatory T-lymphocyte function and Foxp3 expression is downregulated by curcumin. -- Abstract: Curcumin (diferulomethane) is the principal curcuminoid in the spice tumeric and a potent inhibitor of activation-induced T-lymphocyte proliferation; however, the molecular basis of this immunosuppressive effect has not been well studied. Here we show that micromolar concentrations of curcumin inhibited DNA synthesis by mouse CD4{sup +} T-lymphocytes, as well as interleukin-2 (IL-2) and CD25 ({alpha} chain of the high affinity IL-2 receptor) expression in response to antibody-mediated cross-linking of CD3 and CD28. Curcumin acted downstream of protein kinase C activation and intracellular Ca{sup 2+} release to inhibit I{kappa}B phosphorylation, which is required for nuclear translocation of the transcription factor NF{kappa}B. In addition, IL-2-dependent DNA synthesis by mouse CTLL-2 cells, but not constitutive CD25 expression, was impaired in the presence of curcumin, which demonstrated an inhibitory effect on IL-2 receptor (IL-2R) signaling. IL-2-induced phosphorylation of STAT5A and JAK3, but not JAK1, was diminished in the presence of curcumin, indicating inhibition of critical proximal events in IL-2R signaling. In line with the inhibitory action of curcumin on IL-2R signaling, pretreatment of CD4{sup +}CD25{sup +} regulatory T-cells with curcumin downregulated suppressor function, as well as forkhead box p3 (Foxp3) expression. We conclude that curcumin inhibits IL-2 signaling by reducing available IL-2 and high affinity IL-2R, as well as interfering with IL-2R signaling.

  18. Interleukin-1 interaction with neuroregulatory systems: selective enhancement by recombinant human and mouse interleukin-1 of in vitro opioid peptide receptor binding in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Wiedermann, C.J.

    1989-02-01

    Interleukin-1 (IL-1) exerts a wide variety of biological effects on various cell types and may be regarded as a pleiotropic peptide hormone. Biological evidence suggests that IL-1 participates in the modulation of central nervous system physiology and behavior in a fashion characteristic of neuroendocrine hormones. In this investigation, recombinant (r) human (h) IL-1 and r mouse (m) IL-1 were examined for their modulation of opioid peptide receptor binding in vitro. Experiments were performed on frozen sections of rat brain. Receptor binding of radiolabeled substance P and of radiolabeled neurotensin were not significantly affected by the presence of rIL-1s. Recombinant IL-1s, however, significantly enhanced specific binding of 125I-beta-endorphin (125I-beta-END) and of D-ala2-(tyrosyl-3,5-3H)enkephalin-(5-D-leucine) (3H-D-ALA), equipotently and in a concentration-dependent manner with maximal activity occurring at a concentration of 10 LAF units/ml. The increased binding of 125I-beta-END and 3H-D-ALA was blocked steroselectively by (-)-naloxone and by etorphine, suggesting detection of opiate receptors. In addition, brain distribution patterns of receptors labeled in the presence of rIL-1s corresponded to patterns previously published for opiate receptors. Autoradiographic visualization of receptors revealed that rIL-1s in the different areas of the brain exert their effect on opioid binding with comparable potencies. The data suggest that certain central nervous system effects of IL-1s may be mediated by their selective interaction with opiatergic systems at the receptor level.

  19. An Epstein-Barr Virus MicroRNA Blocks Interleukin-1 (IL-1) Signaling by Targeting IL-1 Receptor 1.

    Science.gov (United States)

    Skinner, Camille M; Ivanov, Nikita S; Barr, Sarah A; Chen, Yan; Skalsky, Rebecca L

    2017-11-01

    Epstein-Barr virus (EBV) encodes >44 viral microRNAs (miRNAs) that are differentially expressed throughout infection, can be detected in Epstein-Barr virus (EBV)-positive tumors, and manipulate several biological processes, including cell proliferation, apoptosis, and immune responses. Here, we show that EBV BHRF1-2 miRNAs block NF-κB activation following treatment with proinflammatory cytokines, specifically interleukin-1β (IL-1β). Analysis of EBV PAR-CLIP miRNA targetome data sets combined with pathway analysis revealed multiple BHRF1-2 miRNA targets involved in interleukin signaling pathways. By further analyzing changes in cellular gene expression patterns, we identified the IL-1 receptor 1 (IL1R1) as a direct target of miR-BHRF1-2-5p. Targeting the IL1R1 3' untranslated region (UTR) by EBV miR-BHRF1-2-5p was confirmed using 3'-UTR luciferase reporter assays and Western blot assays. Manipulation of EBV BHRF1-2 miRNA activity in latently infected B cells altered steady-state cytokine levels and disrupted IL-1β responsiveness. These studies demonstrate functionally relevant BHRF1-2 miRNA interactions during EBV infection, which is an important step in understanding their roles in pathogenesis. IMPORTANCE IL-1 signaling plays an important role in inflammation and early activation of host innate immune responses following virus infection. Here, we demonstrate that a viral miRNA downregulates the IL-1 receptor 1 during EBV infection, which consequently alters the responsiveness of cells to IL-1 stimuli and changes the cytokine expression levels within infected cell populations. We postulate that this viral miRNA activity not only disrupts IL-1 autocrine and paracrine signaling loops that can alert effector cells to sites of infection but also provides a survival advantage by dampening excessive inflammation that may be detrimental to the infected cell. Copyright © 2017 American Society for Microbiology.

  20. Internalization of interleukin 1 (IL 1) correlates with IL 1-induced IL 2 receptor expression and IL 2 secretion of EL4 thymoma cells

    OpenAIRE

    Von Hoegen, I.; Falk, Werner; Kojouharoff, G.; Krammer, P. H.

    1989-01-01

    The cytokine interleukin 1 (IL 1) plays an important role in the induction of IL 2 secretion and high-affinity IL 2 receptor (IL 2R) expression by T cells. The events that follow binding of IL 1 to IL 1R, however, are still unknown. In this study we describe two variants of the murine thymoma EL4 (5D3 and D6/76) that express comparable numbers of cell surface IL 1 receptors and bind IL 1 with the same affinity, but show distinct IL 1-dependent IL 2 secretion and IL 2R expression. In the prese...

  1. Different behaviour of radioiodinated human recombinant interleukin-1 and its receptor antagonist in an animal model of infection

    International Nuclear Information System (INIS)

    Laken, C.J. van der; Boerman, O.C.; Oyen, W.J.G.; Ven, M.T.P. van den; Claessens, R.A.M.J.; Meer, J.W.M. van der; Corstens, F.H.M.

    1996-01-01

    Recently, we demonstrated that radiolabelled interleukin-1α (IL-1) specifically accumulates in focal infection in mice through interaction with its receptor. Unfortunately, systemic side-effects of IL-1 limit its clinical application. We investigated whether this problem could be circumvented by using the interleukin-1 receptor antagonist (IL-1ra), an equally sized protein that binds to the same receptors as IL-1 without induction of biological effects. Biodistribution of 125 I-IL-1 and 125 I-IL-1ra was determined in Swiss mice with Staphylococcus aureus-induced abscesses in the left calf muscle at 4, 12, 24 and 48 h after injection of either 0.4 MBq 125 I-IL-1 or 0.4 MBq 125 I-IL-1ra. In vitro, the proteins displayed similar binding characteristics. High-performance liquid chromatographic analysis revealed a tendency for IL-1ra to associate with serum proteins. Both proteins rapidly cleared from most organs. However, the abscess uptake of 125 I-IL-1ra was significantly lower than that of 125 I-IL-1 at all time points (48 h p.i.: 0.06±0.01%ID/g vs 0.60±0.04%ID/g; P 125 I-IL-1ra, while the ratios for 125 I-IL-1 reached 46.9±5.7 at 48 h p.i. Despite similar in vitro receptor binding, the abscess uptake of IL-1ra was much lower than that of IL-1. The interaction of IL-1ra with serum proteins in vivo may reduce its availability for receptor binding in the infection. Although on theoretical grounds IL-1ra is very interesting, these characteristics will prevent its development as a clinically useful radiopharmaceutical to image infection. (orig.). With 4 figs., 2 tabs

  2. G Protein-coupled Receptor Kinases of the GRK4 Protein Subfamily Phosphorylate Inactive G Protein-coupled Receptors (GPCRs).

    Science.gov (United States)

    Li, Lingyong; Homan, Kristoff T; Vishnivetskiy, Sergey A; Manglik, Aashish; Tesmer, John J G; Gurevich, Vsevolod V; Gurevich, Eugenia V

    2015-04-24

    G protein-coupled receptor (GPCR) kinases (GRKs) play a key role in homologous desensitization of GPCRs. It is widely assumed that most GRKs selectively phosphorylate only active GPCRs. Here, we show that although this seems to be the case for the GRK2/3 subfamily, GRK5/6 effectively phosphorylate inactive forms of several GPCRs, including β2-adrenergic and M2 muscarinic receptors, which are commonly used as representative models for GPCRs. Agonist-independent GPCR phosphorylation cannot be explained by constitutive activity of the receptor or membrane association of the GRK, suggesting that it is an inherent ability of GRK5/6. Importantly, phosphorylation of the inactive β2-adrenergic receptor enhanced its interactions with arrestins. Arrestin-3 was able to discriminate between phosphorylation of the same receptor by GRK2 and GRK5, demonstrating preference for the latter. Arrestin recruitment to inactive phosphorylated GPCRs suggests that not only agonist activation but also the complement of GRKs in the cell regulate formation of the arrestin-receptor complex and thereby G protein-independent signaling. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Phorbol ester-induced serine phosphorylation of the insulin receptor decreases its tyrosine kinase activity.

    Science.gov (United States)

    Takayama, S; White, M F; Kahn, C R

    1988-03-05

    The effect of 12-O-tetradecanoylphorbol-13-acetate (TPA) on the function of the insulin receptor was examined in intact hepatoma cells (Fao) and in solubilized extracts purified by wheat germ agglutinin chromatography. Incubation of ortho[32P]phosphate-labeled Fao cells with TPA increased the phosphorylation of the insulin receptor 2-fold after 30 min. Analysis of tryptic phosphopeptides from the beta-subunit of the receptor by reverse-phase high performance liquid chromatography and determination of their phosphoamino acid composition suggested that TPA predominantly stimulated phosphorylation of serine residues in a single tryptic peptide. Incubation of the Fao cells with insulin (100 nM) for 1 min stimulated 4-fold the phosphorylation of the beta-subunit of the insulin receptor. Prior treatment of the cells with TPA inhibited the insulin-stimulated tyrosine phosphorylation by 50%. The receptors extracted with Triton X-100 from TPA-treated Fao cells and purified on immobilized wheat germ agglutinin retained the alteration in kinase activity and exhibited a 50% decrease in insulin-stimulated tyrosine autophosphorylation and phosphotransferase activity toward exogenous substrates. This was due primarily to a decrease in the Vmax for these reactions. TPA treatment also decreased the Km of the insulin receptor for ATP. Incubation of the insulin receptor purified from TPA-treated cells with alkaline phosphatase decreased the phosphate content of the beta-subunit to the control level and reversed the inhibition, suggesting that the serine phosphorylation of the beta-subunit was responsible for the decreased tyrosine kinase activity. Our results support the notion that the insulin receptor is a substrate for protein kinase C in the Fao cell and that the increase in serine phosphorylation of the beta-subunit of the receptor produced by TPA treatment inhibited tyrosine kinase activity in vivo and in vitro. These data suggest that protein kinase C may regulate the function

  4. Growth hormone, interferon-gamma, and leukemia inhibitory factor promoted tyrosyl phosphorylation of insulin receptor substrate-1

    DEFF Research Database (Denmark)

    Argetsinger, L S; Hsu, G W; Myers, M G

    1995-01-01

    ), the principle substrate of the insulin receptor. Tyrosyl phosphorylation of IRS-1 is a critical step in insulin signaling and provides binding sites for proteins with the appropriate Src homology 2 domains, including the 85-kDa regulatory subunit of phosphatidylinositol (PI) 3'-kinase. In 3T3-F442A fibroblasts......., Campbell, G. S., Allevato, G., Billestrup, N., Norstedt, G., and Carter-Su, C. (1994) J. Biol. Chem. 269, 21709-21717). When other cytokines that activate JAK2 were tested for the ability to stimulate the tyrosyl phosphorylation of IRS-1, stimulation was detected with interferon-gamma and leukemia...... to JAK2. GH is also shown to stimulate binding of IRS-1 to the 85-kDa regulatory subunit of PI 3'-kinase. The ability of GH to stimulate tyrosyl phosphorylation of IRS-1 and its association with PI 3'-kinase provides a biochemical basis for responses shared by insulin and GH including the well...

  5. A neuroligin-1-derived peptide stimulates phosphorylation of the NMDA receptor NR1 subunit and rescues MK-801-induced decrease in long-term potentiation and memory impairment

    DEFF Research Database (Denmark)

    Korshunova, Irina; Gjørlund, Michelle D; Jacobsen, Sylwia Owczarek

    2015-01-01

    neurolide-1 effects on short- and long-term social and spatial memory in social recognition, Morris water-maze, and Y-maze tests. We found that subcutaneous neurolide-1 administration, restored hippocampal LTP compromised by NMDA receptor inhibitor MK-801. It counteracted MK-801-induced memory deficit...... in the water-maze and Y-maze tests after long-term treatment (24 h and 1-2 h before the test), but not after short-term exposure (1-2 h). Long-term exposure to neurolide-1 also facilitated social recognition memory. In addition, neurolide-1-induced phosphorylation of the NMDA receptor NR1 subunit on a site...... receptor phosphorylation after treatment with NL1 or a mimetic peptide, neurolide-1, was quantified by immunoblotting. Subsequently, we investigated effects of neurolide-1 on long-term potentiation (LTP) induction in hippocampal slices compromised by NMDA receptor inhibitor MK-801. Finally, we investigated...

  6. Associations between interleukin and interleukin receptor gene polymorphisms and risk of gout.

    Science.gov (United States)

    Liu, Shiguo; Zhou, Zheng; Wang, Can; Guo, Mingzhen; Chu, Nan; Li, Changgui

    2015-09-24

    Gout is a self-limiting, auto-inflammatory arthritis induced by the deposition of monosodium urate crystals in the synovial fluid and periarticular tissues. The aim of this study was to investigate the associations between genetic variants in the interleukin (IL) and interleukin receptor (ILR) genes IL-33, IL-1RL1, IL-23R, and signal transducer and activator of transcription 4 (STAT4) and susceptibility to gout in Chinese Han male individuals. The genetic distributions of rs3939286 in IL-33, rs13015714 in IL-1RL1, rs10889677 in IL-23R, and rs7574865 in STAT4 were detected in 1100 men with gout and 1227 ethnically matched controls, using Taqman allelic discrimination real-time polymerase chain reaction (PCR). Differences in these polymorphisms between the groups were investigated using χ(2) tests. The genotype-phenotype relationship among gout patients was tested by analysis of variance. There was a significant difference in genotypic frequencies of IL-23R rs10889677 between gout patients and controls (χ(2) = 81.386, P gout in Chinese Han male individuals. However, further studies in other ethnic groups are needed to confirm these results.

  7. Association between Interleukin-1 Receptor Antagonist (IL1RN) Variable Number of Tandem Repeats (VNTR) Polymorphism and Pulmonary Tuberculosis.

    Science.gov (United States)

    Hashemi, Mohammad; Naderi, Mohammad; Ebrahimi, Mahboubeh; Amininia, Shadi; Bahari, Gholamreza; Taheri, Mohsen; Eskandari-Nasab, Ebrahim; Ghavami, Saeid

    2015-02-01

    Macrophages and T-lymphocytes are involved in immune response to Mycobacterium tuberculosis. Macrophage produces interleukin (IL)-1 as an inflammatory mediator. IL-1 receptor antagonist (IL1-Ra) is a natural antagonist of IL-1 receptors. In this study we aimed to examine the possible association between the variable number of tandem repeats (VNTR) of the IL-1 receptor antagonist (IL1RN) gene and pulmonary tuberculosis (TB) in a sample of Iranian population. Our study is a case-control study and we examined the VNTR of the IL1RN gene in 265 PTB and 250 healthy subjects by PCR. Neither the overall chi-square comparison of PTB and control subjects nor the logistic regression analysis indicated any association between VNTR IL1RN polymorphism and PTB. Our data suggest that VNTR IL1RN polymorphism may not be associated with the risk of PTB in a sample of Iranian population. Larger studies with different ethnicities are needed to find out the impact of IL1RN VNTR polymorphism on risk of developing TB.

  8. ZINC-INDUCED EGF RECEPTOR SIGNALING REQUIRES SRC-MEDIATED PHOSPHORYLATION OF THE EGF RECEPTOR ON TYROSINE 845 (Y845)

    Science.gov (United States)

    ZINC-INDUCED EGF RECEPTOR SIGNALING REQUIRES Src-MEDIATED PHOSPHORYLATION OF THE EGF RECEPTOR ON TYROSINE 845 (Y845)Weidong Wu1, Lee M. Graves2, Gordon N. Gill3 and James M. Samet4 1Center for Environmental Medicine and Lung Biology; 2Department of Pharmacology, University o...

  9. Interactions among the components of the interleukin-10 receptor complex.

    Science.gov (United States)

    Krause, Christopher D; Mei, Erwen; Mirochnitchenko, Olga; Lavnikova, Natasha; Xie, Junxia; Jia, Yiwei; Hochstrasser, Robin M; Pestka, Sidney

    2006-02-10

    We used fluorescence resonance energy transfer previously to show that the interferon-gamma (IFN-gamma) receptor complex is a preformed entity mediated by constitutive interactions between the IFN-gammaR2 and IFN-gammaR1 chains, and that this preassembled entity changes its structure after the treatment of cells with IFN-gamma. We applied this technique to determine the structure of the interleukin-10 (IL-10) receptor complex and whether it undergoes a similar conformational change after treatment of cells with IL-10. We report that, like the IFN-gamma receptor complex, the IL-10 receptor complex is preassembled: constitutive but weaker interactions occur between the IL-10R1 and IL-10R2 chains, and between two IL-10R2 chains. The IL-10 receptor complex undergoes no major conformational changes when cells are treated with cellular or Epstein-Barr viral IL-10. Receptor complex preassembly may be an inherent feature of Class 2 cytokine receptor complexes.

  10. Identification of steroid-binding and phosphorylated sites within the glucocorticoid receptor

    International Nuclear Information System (INIS)

    Smith, L.I.

    1989-01-01

    The primary goal of these studies was to localize the steroid-binding and phosphorylated sites of the glucocorticoid receptor. The synthetic steroid, dexamethasone 21-mesylate (DM) forms a covalent thioether bond via the sulfhydryl group of a cysteine residue in the receptor. To determine the covalent site of attachment of this ligand, receptors in WEHI-7 mouse thymoma cells were labeled with [ 3 H]DM and purified with a monoclonal antibody. The receptor was completely digested with trypsin and a single peptide covalently labeled with steroid identified by reversed-phase HPLC. This peptide was analyzed by automated Edman degradation to determine the location of the steroid-labeled residue. A similar analysis was performed on an overlapping peptide produced by Staphylococcus aureus protease digestion. Analysis of tryptic peptides from receptors labeled with both [ 3 H]DM and L-[ 35 S]methionine indicated that this peptide contained methionine. These analyses, coupled with the published amino acid sequence of the receptor, identified Cysteine-644 in the steroid-binding domain of the mouse glucocorticoid receptor as the residue involved in covalent steroid-binding. A synthetic peptide representing amino acids 640-650 of the mouse receptor was prepared and analyzed to confirm the identification. These biochemical studies represent a direct demonstration of an amino acid important in receptor function. It has been proposed that the receptor functions through a phosphorylation-dephosphorylation cycle to explain the dependence of hormone binding capacity upon cellular ATP. The glucocorticoid receptor has been shown to be a phosphoprotein. As an initial step to identifying a role of phosphorylation in receptor action, phosphorylated sites within the functional domains of the protein were identified

  11. Interleukin-1 Receptor Antagonist and Interleukin-4 Genes Variable Number Tandem Repeats Are Associated with Adiposity in Malaysian Subjects

    Directory of Open Access Journals (Sweden)

    Yung-Yean Kok

    2017-01-01

    Full Text Available Interleukin-1 receptor antagonist (IL1RA intron 2 86 bp repeat and interleukin-4 (IL4 intron 3 70 bp repeat are variable number tandem repeats (VNTRs that have been associated with various diseases, but their role in obesity is elusive. The objective of this study was to investigate the association of IL1RA and IL4 VNTRs with obesity and adiposity in 315 Malaysian subjects (128 M/187 F; 23 Malays/251 ethnic Chinese/41 ethnic Indians. The allelic distributions of IL1RA and IL4 were significantly different among ethnicities, and the alleles were associated with total body fat (TBF classes. Individuals with IL1RA I/II genotype or allele II had greater risk of having higher overall adiposity, relative to those having the I/I genotype or I allele, respectively, even after controlling for ethnicity [Odds Ratio (OR of I/II genotype = 12.21 (CI = 2.54, 58.79; p=0.002; II allele = 5.78 (CI = 1.73, 19.29; p=0.004]. However, IL4 VNTR B2 allele was only significantly associated with overall adiposity status before adjusting for ethnicity [OR = 1.53 (CI = 1.04, 2.23; p=0.03]. Individuals with IL1RA II allele had significantly higher TBF than those with I allele (31.79±2.52 versus 23.51±0.40; p=0.005. Taken together, IL1RA intron 2 VNTR seems to be a genetic marker for overall adiposity status in Malaysian subjects.

  12. Interleukin 1 receptor antagonist (IL1RN) genetic variations condition post-orthodontic external root resorption in endodontically-treated teeth.

    Science.gov (United States)

    Iglesias-Linares, Alejandro; Yañez-Vico, Rosa Ma; Ballesta-Mudarra, Sofía; Ortiz-Ariza, Estefanía; Mendoza-Mendoza, Asunción; Perea-Pérez, Evelio; Moreno-Fernández, Ana Ma; Solano-Reina, Enrique

    2013-06-01

    External apical root resorption (EARR) is a frequent iatrogenic problem following orthodontic treatment in endodontically-treated teeth, about which the literature reports substantial variability in post-orthodontic treatment EARR responses. The main focus of the present study is to clarify whether variants in the interleukin-1 receptor antagonist gene coding for the IL-1ra protein have a positive/negative influence on EARR of endodontically-treated teeth. Ninety-three orthodontic patients were genetically screened for a single nucleotide polymorphism (SNP:rs419598) in the IL1 cluster. The sample was classified into 2 groups: group 1 (affected-group) showed radiographic EARR of more than 2mm; group 2 (control-group), had no EARR or EARR ≤ to 2mm following orthodontic treatment on root-filled teeth. Logistic regression analysis was performed to obtain an adjusted estimate between the SNPs studied and EARR. Genotype distributions, allelic frequencies, adjusted odds ratios (OR) and 95% confidence intervals were also calculated. We found that subjects homozygous [1/1(TT)] for the IL1RN gene [OR:10.85; p=0.001;CI:95%] were at risk of EARR in root-filled teeth. Genetic variants in the antagonist axis balance of the IL1RN (rs419598) have a direct repercussion on the predisposition to post-orthodontic EARR in root-filled teeth. Variants in allele 1 of the interleukin-1 receptor antagonist gene(rs419598) are associated(p=0.001**) with an increased risk of suffering post-orthodontic EARR in root-filled teeth.

  13. Interleukin 4 signals through two related pathways.

    Science.gov (United States)

    Pernis, A; Witthuhn, B; Keegan, A D; Nelms, K; Garfein, E; Ihle, J N; Paul, W E; Pierce, J H; Rothman, P

    1995-08-15

    The interleukin 4 (IL-4) signaling pathway involves activation, by tyrosine phosphorylation, of two distinct substrates, a signal-transducing factor (STF-IL4) and the IL-4-induced phosphotyrosine substrate (4PS). It is not known whether the IL-4-mediated activation of these substrates occurs via related or distinct signaling pathways. We report that 32D cells, an IL-3-dependent myeloid progenitor cell line in which no phosphorylated 4PS is found, activate high levels of STF-IL4 in response to IL-4. Consistent with the known requirement for 4PS or insulin receptor substrate 1 (IRS-1) in IL-4-mediated mitogenesis, activation of STF-IL4 in 32D cells is not sufficient for IL-4-inducible c-myc expression. In addition, we have examined the ability of 32D cells transfected with different truncation mutants of the human IL-4 receptor to activate Jak-3 kinase and STF-IL4 in response to human IL-4. As in the case of 4PS/IRS-1, we have found that activation of both Jak-3 and STF-IL4 requires the presence of the IL-4 receptor region comprising aa 437-557. The finding that the same region of the IL-4 receptor is required for the induction of both 4PS/IRS-1 and STF-IL4 suggests that the IL-4-stimulated activation of these two substrates might involve common factors.

  14. DMPD: The involvement of the interleukin-1 receptor-associated kinases (IRAKs) incellular signaling networks controlling inflammation. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available ncellular signaling networks controlling inflammation. Ringwood L, Li L. Cytokine. 2008 Apr;42(1):1-7. Epub ...ases (IRAKs) incellular signaling networks controlling inflammation. PubmedID 182...49132 Title The involvement of the interleukin-1 receptor-associated kinases (IRAKs) incellular signaling networks controlling

  15. Changes in plasma concentrations of interleukin-6 and interleukin-1 receptor antagonists in response to adrenaline infusion in humans

    DEFF Research Database (Denmark)

    Søndergaard, S R; Ostrowski, K.; Ullum, H

    2000-01-01

    To investigate the possible role of adrenaline in the response of interleukin (IL)-6 and IL-1 receptor antagonists (ra) to extreme physiological conditions such as trauma and exercise, we examined the concentrations in the plasma of these cytokines during an adrenaline infusion. Given the fact...... that HIV infected patients have elevated levels of IL-6 in plasma, 12 HIV seropositive subjects and 6 HIV seronegative control subjects received a 1-h adrenaline infusion. Baseline concentrations of IL-6 and IL-1ra were higher in the HIV patients compared with the controls (P...), being most pronounced in the untreated subgroup of HIV infected patients (n = 6). The plasma concentration of adrenaline had increased 24-fold after 15 min of adrenaline infusion. The plasma concentration of IL-6 had increased by two- to threefold after 45 min of adrenaline infusion (P

  16. Interleukin-1 receptor type I gene-deficient mice are less susceptible to Staphylococcus epidermidis biomaterial-associated infection than are wild-type mice

    NARCIS (Netherlands)

    Boelens, J. J.; van der Poll, T.; Zaat, S. A.; Murk, J. L.; Weening, J. J.; Dankert, J.

    2000-01-01

    Elevated concentrations of interleukin-1 (IL-1) were found in tissue surrounding biomaterials infected with Staphylococcus epidermidis. To determine the role of IL-1 in biomaterial-associated infection (BAI), IL-1 receptor type I-deficient (IL-1R(-/-)) and wild-type mice received subcutaneous

  17. Neurotensin-induced Erk1/2 phosphorylation and growth of human colonic cancer cells are independent from growth factors receptors activation

    Energy Technology Data Exchange (ETDEWEB)

    Massa, Fabienne; Tormo, Aurelie; Beraud-Dufour, Sophie; Coppola, Thierry [Institut de Pharmacologie Moleculaire et Cellulaire, Universite de Nice-Sophia Antipolis, CNRS UMR 6097, 660 route des Lucioles, 06560 Valbonne (France); Mazella, Jean, E-mail: mazella@ipmc.cnrs.fr [Institut de Pharmacologie Moleculaire et Cellulaire, Universite de Nice-Sophia Antipolis, CNRS UMR 6097, 660 route des Lucioles, 06560 Valbonne (France)

    2011-10-14

    Highlights: {yields} We compare intracellular pathways of NT and EGF in HT29 cells. {yields} NT does not transactivate EGFR. {yields} Transactivation of EGFR is not a general rule in cancer cell growth. -- Abstract: Neurotensin (NT) promotes the proliferation of human colonic cancer cells by undefined mechanisms. We already demonstrated that, in the human colon adenocarcinoma cell line HT29, the effects of NT were mediated by a complex formed between the NT receptor-1 (NTSR1) and-3 (NTSR3). Here we examined cellular mechanisms that led to NT-induced MAP kinase phosphorylation and growth factors receptors transactivation in colonic cancer cells and proliferation in HT29 cells. With the aim to identify upstream signaling involved in NT-elicited MAP kinase activation, we found that the stimulatory effects of the peptide were totally independent from the activation of the epidermal growth factor receptor (EGFR) both in the HT29 and the HCT116 cells. NT was unable to promote phosphorylation of EGFR and to compete with EGF for its binding to the receptor. Pharmacological approaches allowed us to differentiate EGF and NT signaling in HT29 cells since only NT activation of Erk1/2 was shown to be sensitive to PKC inhibitors and since only NT increased the intracellular level of calcium. We also observed that NT was not able to transactivate Insulin-like growth factor receptor. Our findings indicate that, in the HT29 and HCT116 cell lines, NT stimulates MAP kinase phosphorylation and cell growth by a pathway which does not involve EGF system but rather NT receptors which transduce their own intracellular effectors. These results indicate that depending on the cell line used, blocking EGFR is not the general rule to inhibit NT-induced cancer cell proliferation.

  18. Interleukin-6 receptor pathways in coronary heart disease

    DEFF Research Database (Denmark)

    Sarwar, Nadeem; Butterworth, Adam S; Freitag, Daniel F

    2012-01-01

    Persistent inflammation has been proposed to contribute to various stages in the pathogenesis of cardiovascular disease. Interleukin-6 receptor (IL6R) signalling propagates downstream inflammation cascades. To assess whether this pathway is causally relevant to coronary heart disease, we studied ...

  19. Importance of tyrosine phosphorylation in receptor kinase complexes.

    Science.gov (United States)

    Macho, Alberto P; Lozano-Durán, Rosa; Zipfel, Cyril

    2015-05-01

    Tyrosine phosphorylation is an important post-translational modification that is known to regulate receptor kinase (RK)-mediated signaling in animals. Plant RKs are annotated as serine/threonine kinases, but recent work has revealed that tyrosine phosphorylation is also crucial for the activation of RK-mediated signaling in plants. These initial observations have paved the way for subsequent detailed studies on the mechanism of activation of plant RKs and the biological relevance of tyrosine phosphorylation for plant growth and immunity. In this Opinion article we review recent reports on the contribution of RK tyrosine phosphorylation in plant growth and immunity; we propose that tyrosine phosphorylation plays a major regulatory role in the initiation and transduction of RK-mediated signaling in plants. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. The three α1-adrenoceptor subtypes show different spatio-temporal mechanisms of internalization and ERK1/2 phosphorylation.

    Science.gov (United States)

    Perez-Aso, M; Segura, V; Montó, F; Barettino, D; Noguera, M A; Milligan, G; D'Ocon, P

    2013-10-01

    We analyzed the kinetic and spatial patterns characterizing activation of the MAP kinases ERK 1 and 2 (ERK1/2) by the three α1-adrenoceptor (α1-AR) subtypes in HEK293 cells and the contribution of two different pathways to ERK1/2 phosphorylation: protein kinase C (PKC)-dependent ERK1/2 activation and internalization-dependent ERK1/2 activation. The different pathways of phenylephrine induced ERK phosphorylation were determined by western blot, using the PKC inhibitor Ro 31-8425, the receptor internalization inhibitor concanavalin A and the siRNA targeting β-arrestin 2. Receptor internalization properties were studied using CypHer5 technology and VSV-G epitope-tagged receptors. Activation of α1A- and α1B-ARs by phenylephrine elicited rapid ERK1/2 phosphorylation that was directed to the nucleus and inhibited by Ro 31-8425. Concomitant with phenylephrine induced receptor internalization α1A-AR, but not α1B-AR, produced a maintained and PKC-independent ERK phosphorylation, which was restricted to the cytosol and inhibited by β-arrestin 2 knockdown or concanavalin A treatment. α1D-AR displayed constitutive ERK phosphorylation, which was reduced by incubation with prazosin or the selective α1D antagonist BMY7378. Following activation by phenylephrine, α1D-AR elicited rapid, transient ERK1/2 phosphorylation that was restricted to the cytosol and not inhibited by Ro 31-8425. Internalization of the α1D-AR subtype was not observed via CypHer5 technology. The three α1-AR subtypes present different spatio-temporal patterns of receptor internalization, and only α1A-AR stimulation translates to a late, sustained ERK1/2 phosphorylation that is restricted to the cytosol and dependent on β-arrestin 2 mediated internalization. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Plk1 phosphorylation of IRS2 prevents premature mitotic exit via AKT inactivation

    Science.gov (United States)

    Chen, Long; Li, Zhiguo; Ahmad, Nihal; Liu, Xiaoqi

    2016-01-01

    Insulin receptor substrate (IRS) proteins play important roles by acting as a platform in transducing signals from transmembrane receptors upon growth factor stimulation. Although tyrosine phosphorylation on IRS proteins plays critical roles in signal transduction, phosphorylation of IRS proteins on serine/threonine residues are believed to play various regulatory roles on IRS protein function. However, studies on serine/threonine phosphorylation of IRS proteins are very limited, especially for insulin receptor substrate 2 (IRS2), one member of the IRS protein family. In this study, we identify Polo-like kinase 1 (Plk1) as the responsible kinase for phosphorylation of IRS2 on two serine residues, Ser 556 and Ser 1098. Phosphorylation of IRS2 on these two serine residues by Plk1 prevents the activation of the PI3K pathway upon growth factor stimulation by inhibiting the binding between IRS2 and the PI3K pathway components and increasing IRS2 protein degradation. Of significance, we show that IRS2 phosphorylation is cell cycle regulated and that Plk1 phosphorylation of IRS2 prevents premature mitotic exit via AKT inactivation. PMID:25830382

  2. Differential regulation of the transcriptional activity of the glucocorticoid receptor through site-specific phosphorylation

    Directory of Open Access Journals (Sweden)

    Raj Kumar

    2008-08-01

    Full Text Available Raj Kumar1, William J Calhoun21Division of Gastroenterology; 2Division of Allergy, Pulmonary, Immunology, Critical Care, and Sleep (APICS, Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, USAAbstract: Post-translational modifications such as phosphorylation are known to play an important role in the gene regulation by the transcription factors including the nuclear hormone receptor superfamily of which the glucocorticoid receptor (GR is a member. Protein phosphorylation often switches cellular activity from one state to another. Like many other transcription factors, the GR is a phosphoprotein, and phosphorylation plays an important role in the regulation of GR activity. Cell signaling pathways that regulate phosphorylation of the GR and its associated proteins are important determinants of GR function under various physiological conditions. While the role of many phosphorylation sites in the GR is still not fully understood, the role of others is clearer. Several aspects of transcription factor function, including DNA binding affinity, interaction of transactivation domains with the transcription initiation complex, and shuttling between the cytoplasmic compartments, have all been linked to site-specific phosphorylation. All major phosphorylation sites in the human GR are located in the N-terminal domain including the major transactivation domain, AF1. Available literature clearly indicates that many of these potential phosphorylation sites are substrates for multiple kinases, suggesting the potential for a very complex regulatory network. Phosphorylated GR interacts favorably with critical coregulatory proteins and subsequently enhances transcriptional activity. In addition, the activities and specificities of coregulators may be subject to similar regulation by phosphorylation. Regulation of the GR activity due to phosphorylation appears to be site-specific and dependent upon specific cell signaling cascade

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

    International Nuclear Information System (INIS)

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

    1985-01-01

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

  4. β-Adrenergic receptor-mediated suppression of interleukin 2 receptors in human lymphocytes

    International Nuclear Information System (INIS)

    Feldman, R.D.; Hunninghake, G.W.; McArdle, W.L.

    1987-01-01

    Adrenergic receptor agonists are know to attenuate the proliferative response of human lymphocytes after activation; however, their mechanism of action is unknown. Since expression of interleukin 2 (IL-2) receptors is a prerequisite for proliferation, the effect of β-adrenergic receptor agonists on lymphocyte IL-2 receptors was studied on both mitogen-stimulated lymphocytes and IL-2-dependent T lymphocyte cell lines. In both cell types the β-adrenergic receptor agonist isoproterenol blocked the expression of IL-2 receptors, as determined with the IL-2 receptor anti-TAC antibody. To determine the effect of β-adrenergic agonists on expression of the high affinity IL-2 receptors, [ 125 I]IL-2 binding studies were performed at concentrations selective for high affinity sites. No significant effect of β-adrenergic agonists on high affinity IL-2 receptor sites could be detected. The data demonstrate that β-adrenergic receptor agonists down-regulate IL-2 receptors primarily affecting low affinity sites

  5. Tyrosine Phosphorylation in Toll-Like Receptor Signaling

    Science.gov (United States)

    Chattopadhyay, Saurabh; Sen, Ganes C.

    2014-01-01

    There is a wealth of knowledge about how different Ser/Thr protein kinases participate in Toll-like receptor (TLR) signaling. In many cases, we know the identities of the Ser/Thr residues of various components of the TLR-signaling pathways that are phosphorylated, the functional consequences of the phosphorylation and the responsible protein kinases. In contrast, the analysis of Tyr-phosphorylation of TLRs and their signaling proteins is currently incomplete, because several existing analyses are not systematic or they do not rely on robust experimental data. Nevertheless, it is clear that many TLRs require, for signaling, ligand-dependent phosphorylation of specific Tyr residues in their cytoplasmic domains; the list includes TLR2, TLR3, TLR4, TLR5, TLR8 and TLR9. In this article, we discuss the current status of knowledge on the effect of Tyr-phosphorylation of TLRs and their signaling proteins on their biochemical and biological functions, the possible identities of the relevant protein tyrosine kinases (PTKs) and the nature of regulations of PTK-mediated activation of TLR signaling pathways. PMID:25022196

  6. Signal transduction through the IL-4 and insulin receptor families.

    Science.gov (United States)

    Wang, L M; Keegan, A; Frankel, M; Paul, W E; Pierce, J H

    1995-07-01

    Activation of tyrosine kinase-containing receptors and intracellular tyrosine kinases by ligand stimulation is known to be crucial for mediating initial and subsequent events involved in mitogenic signal transduction. Receptors for insulin and insulin-like growth factor 1 (IGF-1) contain cytoplasmic tyrosine kinase domains that undergo autophosphorylation upon ligand stimulation. Activation of these receptors also leads to pronounced and rapid tyrosine phosphorylation of insulin receptor substrate 1 (IRS-1) in cells of connective tissue origin. A related substrate, designated 4PS, is similarly phosphorylated by insulin and IGF-1 stimulation in many hematopoietic cell types. IRS-1 and 4PS possess a number of tyrosine phosphorylation sites that are within motifs that bind specific SH2-containing molecules known to be involved in mitogenic signaling such as PI-3 kinase, SHPTP-2 (Syp) and Grb-2. Thus, they appear to act as docking substrates for a variety of signaling molecules. The majority of hematopoietic cytokines bind to receptors that do not possess intrinsic kinase activity, and these receptors have been collectively termed as members of the hematopoietin receptor superfamily. Despite their lack of tyrosine kinase domains, stimulation of these receptors has been demonstrated to activate intracellular kinases leading to tyrosine phosphorylation of multiple substrates. Recent evidence has demonstrated that activation of different members of the Janus family of tyrosine kinases is involved in mediating tyrosine phosphorylation events by specific cytokines. Stimulation of the interleukin 4 (IL-4) receptor, a member of the hematopoietin receptor superfamily, is thought to result in activation of Jak1, Jak3, and/or Fes tyrosine kinases.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Interleukin 1 induces early protein phosphorylation and requires only a short exposure for late induced secretion of β-endorphin in a mouse pituitary cell line

    International Nuclear Information System (INIS)

    Fagarasan, M.O.; Axelrod, J.; Bishop, J.F.; Rinaudo, M.S.

    1990-01-01

    Previous work has shown that prolonged pretreatment of a mouse anterior pituitary cell line, AtT-20 cells, with the cytokine interleukin 1 (IL-1) stimulates β-endorphin release and potentiates the secretion induced by many secretagogues. Desensitization of protein kinase C (PKC) by pretreatment with phorbol ester [phorbol 12-tetradecanoate 13-acetate (TPA)] for 8 hr abolished the secretion induced by TPA as well as the enhancement of TPA-induced β-endorphin release produced by IL-1. Desensitization of PKC only partly abolished the potentiating effects of IL-1 on corticotropin-releasing factor-induced β-endorphin secretion. In contrast, IL-1-induced β-endorphin release was independent of PKC. The authors observed that treatment of AtT-20 cells with IL-1 markedly phosphorylated 19-, 20-, and 60-kDa proteins within minutes, presumably by early activation of protein kinases. Prolonged treatment with TPA, which was shown to desensitize an 87-kDa protein (a substrate for PKC), had no effect on IL-1-induced phosphorylation of 20-, 60-, and 87-kDa proteins, indicating that the phosphorylation of these proteins does not involve PKC. IL-1 does not generate cAMP in AtT-20 cells, suggesting that a cAMP-dependent protein kinase is also not involved. These observations indicate that once IL-1 generates an early signal, its presence is no longer necessary for the subsequent secretion of β-endorphin

  8. Sigma-1 receptor regulates Tau phosphorylation and axon extension by shaping p35 turnover via myristic acid.

    Science.gov (United States)

    Tsai, Shang-Yi A; Pokrass, Michael J; Klauer, Neal R; Nohara, Hiroshi; Su, Tsung-Ping

    2015-05-26

    Dysregulation of cyclin-dependent kinase 5 (cdk5) per relative concentrations of its activators p35 and p25 is implicated in neurodegenerative diseases. P35 has a short t½ and undergoes rapid proteasomal degradation in its membrane-bound myristoylated form. P35 is converted by calpain to p25, which, along with an extended t½, promotes aberrant activation of cdk5 and causes abnormal hyperphosphorylation of tau, thus leading to the formation of neurofibrillary tangles. The sigma-1 receptor (Sig-1R) is an endoplasmic reticulum chaperone that is implicated in neuronal survival. However, the specific role of the Sig-1R in neurodegeneration is unclear. Here we found that Sig-1Rs regulate proper tau phosphorylation and axon extension by promoting p35 turnover through the receptor's interaction with myristic acid. In Sig-1R-KO neurons, a greater accumulation of p35 is seen, which results from neither elevated transcription of p35 nor disrupted calpain activity, but rather to the slower degradation of p35. In contrast, Sig-1R overexpression causes a decrease of p35. Sig-1R-KO neurons exhibit shorter axons with lower densities. Myristic acid is found here to bind Sig-1R as an agonist that causes the dissociation of Sig-1R from its cognate partner binding immunoglobulin protein. Remarkably, treatment of Sig-1R-KO neurons with exogenous myristic acid mitigates p35 accumulation, diminishes tau phosphorylation, and restores axon elongation. Our results define the involvement of Sig-1Rs in neurodegeneration and provide a mechanistic explanation that Sig-1Rs help maintain proper tau phosphorylation by potentially carrying and providing myristic acid to p35 for enhanced p35 degradation to circumvent the formation of overreactive cdk5/p25.

  9. Phosphorylation of SLP-76 by the ZAP-70 protein-tyrosine kinase is required for T-cell receptor function.

    Science.gov (United States)

    Bubeck Wardenburg, J; Fu, C; Jackman, J K; Flotow, H; Wilkinson, S E; Williams, D H; Johnson, R; Kong, G; Chan, A C; Findell, P R

    1996-08-16

    Two families of tyrosine kinases, the Src and Syk families, are required for T-cell receptor activation. While the Src kinases are responsible for phosphorylation of receptor-encoded signaling motifs and for up-regulation of ZAP-70 activity, the downstream substrates of ZAP-70 are unknown. Evidence is presented herein that the Src homology 2 (SH2) domain-containing leukocyte protein of 76 kDa (SLP-76) is a substrate of ZAP-70. Phosphorylation of SLP-76 is diminished in T cells that express a catalytically inactive ZAP-70. Moreover, SLP-76 is preferentially phosphorylated by ZAP-70 in vitro and in heterologous cellular systems. In T cells, overexpression of wild-type SLP-76 results in a hyperactive receptor, while expression of a SLP-76 molecule that is unable to be tyrosine-phosphorylated attenuates receptor function. In addition, the SH2 domain of SLP-76 is required for T-cell receptor function, although its role is independent of the ability of SLP-76 to undergo tyrosine phosphorylation. As SLP-76 interacts with both Grb2 and phospholipase C-gamma1, these data indicate that phosphorylation of SLP-76 by ZAP-70 provides an important functional link between the T-cell receptor and activation of ras and calcium pathways.

  10. GABAB receptor phosphorylation regulates KCTD12-induced K+ current desensitization

    DEFF Research Database (Denmark)

    Adelfinger, L; Turecek, R; Ivankova, K

    2014-01-01

    released from the G-protein. Receptor-activated K+ currents desensitize in the sustained presence of agonist to avoid excessive effects on neuronal activity. Desensitization of K+ currents integrates distinct mechanistic underpinnings. GABAB receptor activity reduces protein kinase-A activity, which...... reduces phosphorylation of serine-892 in GABAB2 and promotes receptor degradation. This form of desensitization operates on the time scale of several minutes to hours. A faster form of desensitization is induced by the auxiliary subunit KCTD12, which interferes with channel activation by binding to the G......-protein βγ subunits. Here we show that the two mechanisms of desensitization influence each other. Serine-892 phosphorylation in heterologous cells rearranges KCTD12 at the receptor and slows KCTD12-induced desensitization. Likewise, protein kinase-A activation in hippocampal neurons slows fast...

  11. Peri- and Postoperative Treatment with the Interleukin-1 Receptor Antagonist Anakinra Is Safe in Patients Undergoing Renal Transplantation: Case Series and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Catharina M. Mulders-Manders

    2017-05-01

    Full Text Available In patients undergoing solid organ transplantation, the presence of an interleukin-1 (IL-1 driven disease may require the addition of IL-1 inhibiting drugs to the standard immunosuppressive regimen to protect against inflammation and negative graft outcome. Three patients undergoing renal transplantation were treated perioperatively with the interleukin-1 receptor antagonist anakinra. Kidney function increased rapidly in all three and the only complications seen were minor infections. In vitro studies report associations between serum and urinary levels of IL-1β and IL-1 receptor antagonist and negative graft outcome, and studies in animals and two small human trials illustrate a possible protective effect of anti-IL-1 therapy after solid organ transplantation. Peri- and postoperative use of anakinra is safe and effective in patients undergoing renal transplantation.

  12. Soluble intercellular adhesion molecule-1 (sICAM-1) and soluble interleukin-2 receptors (sIL-2R) in scleroderma skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Deleuran, Mette; Heickendorff, Lene

    1998-01-01

    In order to investigate whether soluble intercellular adhesion molecule-1 (sICAM-1) and soluble interleukin-2 receptors (sIL-2R) were present in scleroderma skin, and to compare their levels to concentrations measured in plasma and clinical parameters, we examined suction blister fluid and plasma...... from 13 patients with systemic sclerosis and 11 healthy volunteers. Suction blisters and biopsies were from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin. The levels of sICAM-1 and sIL-2R were significantly increased in both plasma and suction blister fluid from...

  13. RECOMBINANT HUMAN INTERLEUKIN-1 RECEPTOR ANTAGONIST IN THE TREATMENT OF PATIENTS WITH SEPSIS SYNDROME - RESULTS FROM A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED TRIAL

    NARCIS (Netherlands)

    FISHER, C. J.; DHAINAUT, J. F. A.; Opal, S. M.; Pribble, J. P.; BALK, R. A.; SLOTMAN, G. J.; IBERTI, T. J.; RACKOW, E. C.; SHAPIRO, M. J.; GREENMAN, R. L.; REINES, H. D.; SHELLY, M. P.; THOMPSON, B. W.; LABRECQUE, J. F.; Catalano, M. A.; KNAUS, W. A.; Sadoff, J. C.; ASTIZ, M.; CARPATI, C.; BONE, R. C.; FREIDMAN, B.; MURE, A. J.; BRATHWAITE, C.; SHAPIRO, E.; MELHORN, L.; TAYLOR, R.; KEEGAN, M.; OBRIEN, J.; SCHEIN, R.; PENA, M.; WASSERLOUF, M.; OROPELLO, J.; BENJAMIN, E.; DELGUIDICE, R.; EMMANUEL, G.; LIE, T.; Anderson, L.; Marshall, J.; DEMAJO, W.; ROTSTEIN, O.; FOSTER, D.; Abraham, E.; MIDDLETON, H.; Perry, C.; LEVY, H.; FRY, D. E.; SIMPSON, S. Q.; CROWELL, R. E.; Neidhart, M.; Stevens, D.; COFFMAN, T.; NARASIMHAM, N.; MERRICK, D. K.; BERGQUIST, W.; MATZEL, K. E.; HUEBLER, M.; Foulke, G. E.; ALBERTSON, T. E.; WALBY, W. F.; ALLEN, R. P.; Baughman, R.; HASSELGREN, P. O.; Fink, M. P.; FAVORITO, F.; THOMPSON, B. T.; CORBIN, R.; SHELLHORSE, G. Y.; FRAZIER, A.; White, S.; GARRARD, C.; ACOURT, C.; STORER, S.; GERVICH, D. H.; FOSHE, D.; BRASE, R.; BAGDAHN, A.; COONEY, R.; Smith, J. S.; MARTIN, L. F.; Vincent, J. L.; Friedman, G.; Berlot, G.; FLETCHER, J. R.; WILLIAMS, M. D.; WRIGHT, T. F.; Johnson, S.; FEILD, C.; WOLF, K.; MACINTYRE, N.; DUBIN, H. G.; DURKIN, M. R.; DUBIN, P. K.; STAUBACH, K. H.; FEIN, A. M.; SCHULMAN, D. B.; NIEDERMAN, M. S.; CHALFIN, D. B.; van Leeuwen, P. A. M.; Boermeester, M. A.; Schneider, A. J.; BANDER, J.; IMM, A.; BERNARD, G.; Nelson, L.; Stroud, M.; SAFCSAK, K.; CERRA, F.; RINDAL, J.; Mann, H.; HALPERN, N.; SILVERSTEIN, J.; ALICEA, M.; Sibbald, W. J.; MARTIN, C. M.; RUTLEDGE, F. S.; PETTI, K.; RUSSELL, J. A.; KRUGER, R.; DRUMMOND, A.; LANGE, P.; SEIFERT, T.; DUROCHER, A.; TENAILLON, A.; BOITEAU, R.; LHERM, T.; Lowry, S. F.; Coyle, S. M.; Barie, P. S.; DEMARIA, E.; SNYDMAN, D. R.; SCHWAITZBERG, S. D.; NASRAWAY, S. A.; GRINDLINGER, J.; SUMMER, W.; DEBOISBLANC, B.; WAHL, M.; ALESTIG, K.; GROSSMAN, J.; MAKI, D.; PAZ, H. L.; Weiner, M.; BIHARI, D.; Campbell, D.; BLEICHNER, G.; DAHN, M. S.; LANGE, M. P. A.; Hall, J.; POHLMAN, A.; WENZEL, R. P.; GROSSERODE, M.; COSTIGAN, M.; MILESKI, W.; WEIGELT, J.; YESTON, N.; IRIZARRY, C.; Ross, J.; ROBBINS, J.; NIGHTINGALE, P.; OWEN, K.; SANDSTEDT, S.; Berg, S.; SIMON, G. L.; SENEFF, M. G.; CONRY, K. M.; ZIMMERMAN, J. L.; Dellinger, R. P.; Johnston, R.; ALLEE, P.; GRANDE, P. O.; MYHRE, E.; DHAINAUT, J. F.; HAMY, I.; Mira, J. P.; HARMON, J.; White, J.; MCKIE, L.; SILVERMAN, H.; TUMA, P.; Bennett, D.; PORTER, J. C.; LAURELL, M. H.; Jacobs, S.; ASH, S.; Stiles, D. M.; PRIOR, M. J.; KNATTERUD, G.; TERRIN, M.; KUFERA, J.; WILKENS, P.; RA, K.; MONROE, L.; SPRUNG, C.; HAMILTON, C. M.; MATTHAY, R.; MCCABE, W.; TONASCIA, J.; WIEDEMAN, H.; Wittes, J.; CAMPION, G. V.; CROFT, C. R.; LUSTICK, R.; LOOKABAUGH, J.; GORDON, G. S.; NOE, L.; BLOEDOW, D.; SMITH, C. G.; BRANNON, D.; KUSH, R.; NG, D.; MOORE, E.; BAZEMORE, K.; GALVAN, M.; Wagner, D.; HARRELL, F.; STABLEIN, D.

    1994-01-01

    Objective.-To further define the safety and efficacy of recombinant human interleukin 1 receptor antagonist (rhlL-1ra) in the treatment of sepsis syndrome. Study Design.-Randomized, double-blind, placebo-controlled, multicenter, multinational clinical trial. Population.-A total of 893 patients with

  14. Proinflammatory genotype of interleukin-1 and interleukin-1 receptor antagonist is associated with ESRD in proteinase 3-ANCA vasculitis patients.

    Science.gov (United States)

    Borgmann, Stefan; Endisch, Georg; Hacker, Ulrich T; Song, Bong-Seok; Fricke, Harald

    2003-05-01

    Small-vessel vasculitides are associated with antineutrophil cytoplasmic antibodies (ANCAs). Cytoplasmic ANCAs are targeted mainly against proteinase 3 (PR3), whereas myeloperoxidase (MPO) is the major antigen of perinuclear ANCAs. These relapsing vasculitides show heterogeneous clinical pictures, and disease severity may vary broadly from mild local organ manifestation to acute organ failure (eg, renal failure). We tested whether two cytokine polymorphisms in the interleukin-1beta (IL-1beta) and IL-1 receptor antagonist (IL-1ra) genes, known to determine cytokine secretion, are associated with clinical manifestations and outcome of ANCA-associated vasculitides. Polymerase chain reaction and restriction fragment length polymorphism analyses were performed to determine polymorphisms in the IL-1beta and IL-1ra genes in 79 patients with PR3-ANCA, 30 patients with MPO-ANCA vasculitis, and 196 healthy controls. The frequency of the so-called proinflammatory genotype, characterized by high secretion of IL-1beta and low secretion of its antagonist IL-1ra, was increased significantly in patients with PR3-ANCA with end-stage renal disease. Patients with a renal manifestation of PR3-ANCA vasculitis have an increased risk for developing end-stage renal disease when carrying the proinflammatory IL-1beta/IL-1ra genotype. Anti-inflammatory therapy specifically antagonizing the proinflammatory effect of IL-1beta may be a promising treatment for patients with Wegener's granulomatosis with renal manifestations.

  15. Levels of inhibitors of tumor necrosis factor alpha and interleukin 1beta in urine and sera of patients with urosepsis

    NARCIS (Netherlands)

    Olszyna, D. P.; Prins, J. M.; Buis, B.; van Deventer, S. J.; Speelman, P.; van der Poll, T.

    1998-01-01

    The antiinflammatory cytokine response during urosepsis was determined by measurement of concentrations of soluble tumor necrosis factor receptor (sTNFR) types I and II, interleukin 1 receptor antagonist (IL-1ra), soluble IL-1 receptor type II (sIL-1RII), and interleukin 10 in sera and urine of 30

  16. Interleukin-1 Receptor Antagonist Gene Polymorphism in Patients with Coronary Artery Diseases

    International Nuclear Information System (INIS)

    Abdel Aziz, A.F.; El Said, A.M.; El Maghraby, T.K.; Hassan, M.M.

    2012-01-01

    Cytokine gene variations are contributory factors in inflammatory pathology. Allele frequencies of Interleukin-1 receptor antagonist (IL-1Ra) gene intron 2 VNTR were measured in healthy blood donors (healthy control subjects) and patients with angina, myocardial infarction (MI) and acute coronary syndrome(ACS). Patients were classified into three groups: thirty one MI patients, twenty two angina patients and thirteen ACS patients. A1/A2 genotype showed significant resistant factor for angina and myocardial infarction and angina (70.97% vs. 29.03%; p=0.0001, 70.97% vs. 31.82%; p0.0004, respectively). A1/A1 homo zygote was a risk factor in MI and angina (p=0.012; p= 0.0001), Moreover, A1/A3 and A2/A3 heterozygotes were found in MI only (p= 0.025; p= 0.0047, respectively). All genotypes didn't show any effect on ACS patients. In conclusion, the data reflected that A1/A1 homo zygote was considered as a significantly risk factor associated with patients with angina as well as MI patients. But, A1/A2 heterozygote was considered a resistance factor against both diseases.

  17. NADPH oxidase 1 deficiency alters caveolin phosphorylation and angiotensin II-receptor localization in vascular smooth muscle.

    Science.gov (United States)

    Basset, Olivier; Deffert, Christine; Foti, Michelangelo; Bedard, Karen; Jaquet, Vincent; Ogier-Denis, Eric; Krause, Karl-Heinz

    2009-10-01

    The superoxide-generating NADPH oxidase NOX1 is thought to be involved in signaling by the angiotensin II-receptor AT1R. However, underlying signaling steps are poorly understood. In this study, we investigated the effect of AngII on aortic smooth muscle from wild-type and NOX1-deficient mice. NOX1-deficient cells showed decreased basal ROS generation and did not produce ROS in response to AngII. Unexpectedly, AngII-dependent Ca(2+) signaling was markedly decreased in NOX1-deficient cells. Immunostaining demonstrated that AT1R was localized on the plasma membrane in wild-type, but intracellularly in NOX1-deficient cells. Immunohistochemistry and immunoblotting showed a decreased expression of AT1R in the aorta of NOX1-deficient mice. To investigate the basis of the abnormal AT1R targeting, we studied caveolin expression and phosphorylation. The amounts of total caveolin and of caveolae were not different in NOX1-deficient mice, but a marked decrease occurred in the phosphorylated form of caveolin. Exogenous H(2)O(2) or transfection of a NOX1 plasmid restored AngII responses in NOX1-deficient cells. Based on these findings, we propose that NOX1-derived reactive oxygen species regulate cell-surface expression of AT1R through mechanisms including caveolin phosphorylation. The lack cell-surface AT1R expression in smooth muscle could be involved in the decreased blood pressure in NOX1-deficient mice.

  18. Associations between interleukin and interleukin receptor gene polymorphisms and risk of gout

    Science.gov (United States)

    Liu, Shiguo; Zhou, Zheng; Wang, Can; Guo, Mingzhen; Chu, Nan; Li, Changgui

    2015-01-01

    Gout is a self-limiting, auto-inflammatory arthritis induced by the deposition of monosodium urate crystals in the synovial fluid and periarticular tissues. The aim of this study was to investigate the associations between genetic variants in the interleukin (IL) and interleukin receptor (ILR) genes IL-33, IL-1RL1, IL-23R, and signal transducer and activator of transcription 4 (STAT4) and susceptibility to gout in Chinese Han male individuals. The genetic distributions of rs3939286 in IL-33, rs13015714 in IL-1RL1, rs10889677 in IL-23R, and rs7574865 in STAT4 were detected in 1100 men with gout and 1227 ethnically matched controls, using Taqman allelic discrimination real-time polymerase chain reaction (PCR). Differences in these polymorphisms between the groups were investigated using χ2 tests. The genotype-phenotype relationship among gout patients was tested by analysis of variance. There was a significant difference in genotypic frequencies of IL-23R rs10889677 between gout patients and controls (χ2 = 81.386, P < 0.001). However, there were no significant differences in distributions of the other polymorphisms between the groups. Our results revealed that the rs10889677 variant in IL-23R may be involved in the development of gout in Chinese Han male individuals. However, further studies in other ethnic groups are needed to confirm these results. PMID:26399911

  19. Coordinate phosphorylation of insulin-receptor kinase and its 175,000-Mr endogenous substrate in rat hepatocytes

    International Nuclear Information System (INIS)

    Okamoto, M.; Karasik, A.; White, M.F.; Kahn, C.R.

    1991-01-01

    To investigate the early events in insulin signal transmission in liver, isolated rat hepatocytes were labeled with 32 P, and proteins phosphorylated in response to insulin were detected by immunoprecipitation with anti-phosphotyrosine and anti-receptor antibodies and analyzed by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis and autoradiography. In these cells, insulin rapidly stimulated tyrosine phosphorylation of the 95,000-Mr beta-subunit of the insulin receptor and a 175,000-Mr phosphoprotein (pp175). Both proteins were precipitated by anti-phosphotyrosine antibody, whereas only the insulin receptor was recognized with anti-insulin-receptor antibody. In the insulin-stimulated state, both pp175 and the receptor beta-subunit were found to be phosphorylated on tyrosine and serine residues. Based on precipitation by the two antibodies, receptor phosphorylation was biphasic with an initial increase in tyrosine phosphorylation followed by a more gradual increase in serine phosphorylation over the first 30 min of stimulation. The time course of phosphorylation of pp175 was rapid and paralleled that of the beta-subunit of the insulin receptor. The pp175 was clearly distinguished from the insulin receptor, because it was detected only when boiling SDS was used to extract cellular phosphoproteins, whereas the insulin receptor was extracted with either Triton X-100 or SDS. In addition, the tryptic peptide maps of the two proteins were distinct. The dose-response curve for insulin stimulation was shifted slightly to the left of the insulin receptor, suggesting some signal amplification at this step. These data suggest that pp175 is a major endogenous substrate of the insulin receptor in liver and may be a cytoskeletal-associated protein

  20. Urokinase receptor expression involves tyrosine phosphorylation of phosphoglycerate kinase.

    Science.gov (United States)

    Shetty, Praveenkumar; Velusamy, Thirunavukkarasu; Bhandary, Yashodhar P; Liu, Ming C; Shetty, Sreerama

    2010-02-01

    The interaction of urokinase-type plasminogen activator (uPA) with its receptor, uPAR, plays a central role in several pathophysiological processes, including cancer. uPA induces its own cell surface receptor expression through stabilization of uPAR mRNA. The mechanism involves binding of a 51 nt uPAR mRNA coding sequence with phosphoglycerate kinase (PGK) to down regulate cell surface uPAR expression. Tyrosine phosphorylation of PGK mediated by uPA treatment enhances uPAR mRNA stabilization. In contrast, inhibition of tyrosine phosphorylation augments PGK binding to uPAR mRNA and attenuates uPA-induced uPAR expression. Mapping the specific peptide region of PGK indicated that its first quarter (amino acids 1-100) interacts with uPAR mRNA. To determine if uPAR expression by uPA is regulated through activation of tyrosine residues of PGK, we mutated the specific tyrosine residue and tested mutant PGK for its ability to interfere with uPAR expression. Inhibition of tyrosine phosphorylation by mutating Y76 residue abolished uPAR expression induced by uPA treatment. These findings collectively demonstrate that Y76 residue present in the first quarter of the PGK molecule is involved in lung epithelial cell surface uPAR expression. This region can effectively mimic the function of a whole PGK molecule in inhibiting tumor cell growth.

  1. Phosphorylation of G Protein-Coupled Receptors: From the Barcode Hypothesis to the Flute Model.

    Science.gov (United States)

    Yang, Zhao; Yang, Fan; Zhang, Daolai; Liu, Zhixin; Lin, Amy; Liu, Chuan; Xiao, Peng; Yu, Xiao; Sun, Jin-Peng

    2017-09-01

    Seven transmembrane G protein-coupled receptors (GPCRs) are often phosphorylated at the C terminus and on intracellular loops in response to various extracellular stimuli. Phosphorylation of GPCRs by GPCR kinases and certain other kinases can promote the recruitment of arrestin molecules. The arrestins critically regulate GPCR functions not only by mediating receptor desensitization and internalization, but also by redirecting signaling to G protein-independent pathways via interactions with numerous downstream effector molecules. Accumulating evidence over the past decade has given rise to the phospho-barcode hypothesis, which states that ligand-specific phosphorylation patterns of a receptor direct its distinct functional outcomes. Our recent work using unnatural amino acid incorporation and fluorine-19 nuclear magnetic resonance ( 19 F-NMR) spectroscopy led to the flute model, which provides preliminary insight into the receptor phospho-coding mechanism, by which receptor phosphorylation patterns are recognized by an array of phosphate-binding pockets on arrestin and are translated into distinct conformations. These selective conformations are recognized by various effector molecules downstream of arrestin. The phospho-barcoding mechanism enables arrestin to recognize a wide range of phosphorylation patterns of GPCRs, contributing to their diverse functions. Copyright © 2017 by The Author(s).

  2. Toll-like receptor induced pro-interleukin-1β and interleukin-6 in monocytes are lower in healthy infants compared to adults.

    Science.gov (United States)

    Libraty, Daniel H; Zhang, Lei; Woda, Marcia; Acosta, Luz P; Obcena, Anamae; Brion, Job D; Capeding, Rosario Z

    2013-01-01

    Infants have long been known to have higher infectious diseases morbidity and mortality and suboptimal vaccination responses compared to older children and adults. A variety of differences in innate and adaptive immune responses have been described between these two groups. We compared Toll-like receptor (TLR)-induced production of pro-interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α between 2-month-old infants and adults. TLR 7/8-induced production of pro-IL-1β and IL-6 in monocytes was lower in 2-month-old infants compared to adults. There was no difference in TLR 7/8-induced production of TNF-α. Lower TLR-induced production of pro-IL-1β and IL-6 in innate immune cells during early infancy likely contributes to suboptimal vaccine responses and infectious diseases susceptibility.

  3. Toll-like receptor induced pro-interleukin-1β and interleukin-6 in monocytes are lower in healthy infants compared to adults.

    Directory of Open Access Journals (Sweden)

    Daniel H Libraty

    Full Text Available Infants have long been known to have higher infectious diseases morbidity and mortality and suboptimal vaccination responses compared to older children and adults. A variety of differences in innate and adaptive immune responses have been described between these two groups. We compared Toll-like receptor (TLR-induced production of pro-interleukin (IL-1β, IL-6, and tumor necrosis factor (TNF-α between 2-month-old infants and adults. TLR 7/8-induced production of pro-IL-1β and IL-6 in monocytes was lower in 2-month-old infants compared to adults. There was no difference in TLR 7/8-induced production of TNF-α. Lower TLR-induced production of pro-IL-1β and IL-6 in innate immune cells during early infancy likely contributes to suboptimal vaccine responses and infectious diseases susceptibility.

  4. Generation and Characterization of Mice Expressing a Conditional Allele of the Interleukin-1 Receptor Type 1.

    Directory of Open Access Journals (Sweden)

    Matthew J Robson

    Full Text Available The cytokines IL-1α and IL-1β exert powerful pro-inflammatory actions throughout the body, mediated primarily by the intracellular signaling capacity of the interleukin-1 receptor (IL-1R1. Although Il1r1 knockout mice have been informative with respect to a requirement for IL-1R1 signaling in inflammatory events, the constitutive nature of gene elimination has limited their utility in the assessment of temporal and spatial patterns of cytokine action. To pursue such questions, we have generated C57Bl/6J mice containing a floxed Il1r1 gene (Il1r1loxP/loxP, with loxP sites positioned to flank exons 3 and 4 and thereby the ability to spatially and temporally eliminate Il1r1 expression and signaling. We found that Il1r1loxP/loxP mice breed normally and exhibit no gross physical or behavioral phenotypes. Moreover, Il1r1loxP/loxP mice exhibit normal IL-1R1 receptor expression in brain and spleen, as well as normal IL-1R1-dependent increases in serum IL-6 following IL-1α injections. Breeding of Il1r1loxP/loxP mice to animals expressing a cytomegalovirus (CMV-driven Cre recombinase afforded efficient excision at the Il1r1 locus. The Il1r1loxP/loxP line should be a valuable tool for the assessment of contributions made by IL-1R1 signaling in diverse cell types across development.

  5. Interleukin-1β inhibits insulin signaling and prevents insulin-stimulated system A amino acid transport in primary human trophoblasts.

    Science.gov (United States)

    Aye, Irving L M H; Jansson, Thomas; Powell, Theresa L

    2013-12-05

    Interleukin-1β (IL-1β) promotes insulin resistance in tissues such as liver and skeletal muscle; however the influence of IL-1β on placental insulin signaling is unknown. We recently reported increased IL-1β protein expression in placentas of obese mothers, which could contribute to insulin resistance. In this study, we tested the hypothesis that IL-1β inhibits insulin signaling and prevents insulin-stimulated amino acid transport in cultured primary human trophoblast (PHT) cells. Cultured trophoblasts isolated from term placentas were treated with physiological concentrations of IL-1β (10pg/ml) for 24h. IL-1β increased the phosphorylation of insulin receptor substrate-1 (IRS-1) at Ser307 (inhibitory) and decreased total IRS-1 protein abundance but did not affect insulin receptor β expression. Furthermore, IL-1β inhibited insulin-stimulated phosphorylation of IRS-1 (Tyr612, activation site) and Akt (Thr308) and prevented insulin-stimulated increase in PI3K/p85 and Grb2 protein expression. IL-1β alone stimulated cRaf (Ser338), MEK (Ser221) and Erk1/2 (Thr202/Tyr204) phosphorylation. The inflammatory pathways nuclear factor kappa B and c-Jun N-terminal kinase, which are involved in insulin resistance, were also activated by IL-1β treatment. Moreover, IL-1β inhibited insulin-stimulated System A, but not System L amino acid uptake, indicating functional impairment of insulin signaling. In conclusion, IL-1β inhibited the insulin signaling pathway by inhibiting IRS-1 signaling and prevented insulin-stimulated System A transport, thereby promoting insulin resistance in cultured PHT cells. These findings indicate that conditions which lead to increased systemic maternal or placental IL-1β levels may attenuate the effects of maternal insulin on placental function and consequently fetal growth. Published by Elsevier Ireland Ltd.

  6. Functional expression of BMP7 receptors in oral epithelial cells. Interleukin-17F production in response to BMP7.

    Science.gov (United States)

    Nishio, Kensuke; Ozawa, Yasumasa; Ito, Hisanori; Kifune, Takashi; Narita, Tatsuya; Iinuma, Toshimitsu; Gionhaku, Nobuhito; Asano, Masatake

    2017-10-01

    Bone morphogenetic proteins (BMPs) are members of the transforming growth factor-β (TGF-β) superfamily. Recently, BMP7 has been demonstrated to be produced by salivary glands and contribute to embryonic branching in mice. The BMP7 in saliva is thought to be delivered to the oral cavity and is expected to contact with stratified squamous epithelial cells which line the surface of oral mucosa. In this study, we attempted to investigate the effects of BMP7 on oral epithelial cells. The expression of BMP receptors was examined by reverse transcriptase-polymerase chain reaction (RT-PCR). OSCCs were stimulated with human recombinant BMP7 (hrBMP7) and the phosphorylation status of Smad1/5/8 was examined by western blotting. For microarray analysis, Ca9-22 cells were stimulated with 100 ng/mL of hrBMP7 and total RNA was extracted and subjected to real-time PCR. The 5'-untranslated region (5'-UTR) of IL-17 F gene was cloned to pGL4-basic vector and used for luciferase assay. Ca9-22 cells were pre-incubated with DM3189, a specific inhibitor of Smad1/5/8, for inhibition assay. All isoforms of type I and type II BMP receptors were expressed in both Ca9-22 and HSC3 cells and BMP7 stimulation resulted in the phosphorylation of Smad1/5/8 in both cell lines. The microarray analysis revealed the induction of interleukin-17 F (IL-17 F), netrin G2 (NTNG2) and hyaluronan synthase 1 (HAS1). Luciferase assay using the 5'-UTR of the IL-17 F gene revealed transcriptional regulation. Induced IL-17 F production was further confirmed at the protein level by ELISA. Smad1/5/8 inhibitor pretreatment decreased IL-17 F expression levels in the cells.

  7. Role of interleukin-1 receptor signaling in the behavioral effects of ethanol and benzodiazepines.

    Science.gov (United States)

    Blednov, Yuri A; Benavidez, Jillian M; Black, Mendy; Mayfield, Jody; Harris, R Adron

    2015-08-01

    Gene expression studies identified the interleukin-1 receptor type I (IL-1R1) as part of a pathway associated with a genetic predisposition to high alcohol consumption, and lack of the endogenous IL-1 receptor antagonist (IL-1ra) strongly reduced ethanol intake in mice. Here, we compared ethanol-mediated behaviors in mice lacking Il1rn or Il1r1. Deletion of Il1rn (the gene encoding IL-1ra) increases sensitivity to the sedative/hypnotic effects of ethanol and flurazepam and reduces severity of acute ethanol withdrawal. Conversely, deletion of Il1r1 (the gene encoding the IL-1 receptor type I, IL-1R1) reduces sensitivity to the sedative effects of ethanol and flurazepam and increases the severity of acute ethanol withdrawal. The sedative effects of ketamine and pentobarbital were not altered in the knockout (KO) strains. Ethanol intake and preference were not changed in mice lacking Il1r1 in three different tests of ethanol consumption. Recovery from ethanol-induced motor incoordination was only altered in female mice lacking Il1r1. Mice lacking Il1rn (but not Il1r1) showed increased ethanol clearance and decreased ethanol-induced conditioned taste aversion. The increased ethanol- and flurazepam-induced sedation in Il1rn KO mice was decreased by administration of IL-1ra (Kineret), and pre-treatment with Kineret also restored the severity of acute ethanol withdrawal. Ethanol-induced sedation and withdrawal severity were changed in opposite directions in the null mutants, indicating that these responses are likely regulated by IL-1R1 signaling, whereas ethanol intake and preference do not appear to be solely regulated by this pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Role of Interleukin-6 and Its Receptor in Endometriosis

    OpenAIRE

    Li, Shihui; Fu, Xiaoxia; Wu, Tingting; Yang, Liwei; Hu, Changchang; Wu, RuiJin

    2017-01-01

    Background Studies have shown that the concentration of interleukin (IL)-6 in peritoneal fluid is increased in patients with endometriosis; however, whether the disorders involving IL-6 contribute to the development of endometriosis is still unclear. In the present study, we evaluated the potential role of IL-6 and IL-6 receptor (IL-6R) in the pathogenesis of endometriosis. Material/Methods We examined activated macrophages and the expression of membrane-binding receptor (mIL-6R) in peritonea...

  9. Coarse-grained molecular simulation of epidermal growth factor receptor protein tyrosine kinase multi-site self-phosphorylation.

    Directory of Open Access Journals (Sweden)

    John G Koland

    2014-01-01

    Full Text Available Upon the ligand-dependent dimerization of the epidermal growth factor receptor (EGFR, the intrinsic protein tyrosine kinase (PTK activity of one receptor monomer is activated, and the dimeric receptor undergoes self-phosphorylation at any of eight candidate phosphorylation sites (P-sites in either of the two C-terminal (CT domains. While the structures of the extracellular ligand binding and intracellular PTK domains are known, that of the ∼225-amino acid CT domain is not, presumably because it is disordered. Receptor phosphorylation on CT domain P-sites is critical in signaling because of the binding of specific signaling effector molecules to individual phosphorylated P-sites. To investigate how the combination of conventional substrate recognition and the unique topological factors involved in the CT domain self-phosphorylation reaction lead to selectivity in P-site phosphorylation, we performed coarse-grained molecular simulations of the P-site/catalytic site binding reactions that precede EGFR self-phosphorylation events. Our results indicate that self-phosphorylation of the dimeric EGFR, although generally believed to occur in trans, may well occur with a similar efficiency in cis, with the P-sites of both receptor monomers being phosphorylated to a similar extent. An exception was the case of the most kinase-proximal P-site-992, the catalytic site binding of which occurred exclusively in cis via an intramolecular reaction. We discovered that the in cis interaction of P-site-992 with the catalytic site was facilitated by a cleft between the N-terminal and C-terminal lobes of the PTK domain that allows the short CT domain sequence tethering P-site-992 to the PTK core to reach the catalytic site. Our work provides several new mechanistic insights into the EGFR self-phosphorylation reaction, and demonstrates the potential of coarse-grained molecular simulation approaches for investigating the complexities of self-phosphorylation in

  10. Phosphorylation inhibits DNA-binding of alternatively spliced aryl hydrocarbon receptor nuclear translocator

    International Nuclear Information System (INIS)

    Kewley, Robyn J.; Whitelaw, Murray L.

    2005-01-01

    The basic helix-loop-helix/PER-ARNT-SIM homology (bHLH/PAS) transcription factor ARNT (aryl hydrocarbon receptor nuclear translocator) is a key component of various pathways which induce the transcription of cytochrome P450 and hypoxia response genes. ARNT can be alternatively spliced to express Alt ARNT, containing an additional 15 amino acids immediately N-terminal to the DNA-binding basic region. Here, we show that ARNT and Alt ARNT proteins are differentially phosphorylated by protein kinase CKII in vitro. Phosphorylation had an inhibitory effect on DNA-binding to an E-box probe by Alt ARNT, but not ARNT, homodimers. This inhibitory phosphorylation occurs through Ser77. Moreover, a point mutant, Alt ARNT S77A, shows increased activity on an E-box reporter gene, consistent with Ser77 being a regulatory site in vivo. In contrast, DNA binding by an Alt ARNT/dioxin receptor heterodimer to the xenobiotic response element is not inhibited by phosphorylation with CKII, nor does Alt ARNT S77A behave differently from wild type Alt ARNT in the context of a dioxin receptor heterodimer

  11. Characterization of the interleukin 3 receptor

    International Nuclear Information System (INIS)

    Murthy, S.C.; Mui, A.L.; Krystal, G.

    1990-01-01

    A variety of homobifunctional crosslinking agents have been used to gain insight into the nature of the murine interleukin 3 (mIL-3) receptor. When [125I]mIL-3 was cross-linked to receptor sites on the surfaces of intact B6SUtA1 cells with disuccinimidyl suberate (DSS), sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed the existence of two radiolabeled species with molecular weights of 140 (p140) and 70 (p70) kd (after subtraction of [125I]mIL-3). The relative intensities of the two bands did not change when the [125I]mIL-3 concentration was varied, confirming Scatchard results which suggested only one affinity class. However, when [125I]mIL-3 was crosslinked to intact cells and then incubated at 37 degrees C, the intensity of p140 decreased relative to p70, suggesting a conversion of p140 to p70. This conversion could be inhibited by sodium azide, methylamine, and bacitracin and could also be prevented by first boiling for 1 min in 2% SDS and 5% 2-mercaptoethanol. The putative protease that carried out this apparent conversion appeared to be associated both with plasma membranes prepared from these cells and also with solubilized receptors. Moreover, when p140, crosslinked with both dithiobis succinimidylpropionate and glutaraldehyde, was purified and reelectrophoresed under reducing conditions, p70 could be generated. N-glycanase digestion of p140 and p70 revealed a similar level of N-linked carbohydrate, which upon closer study appeared to consist of two chains, a 3-kd and an 8-kd moiety. Consistent with this data, we propose that the receptor is a 140-kd glycoprotein that is cleaved to a 70-kd surface protein upon mIL-3 binding and chemical crosslinking

  12. Characterization of a receptor for human monocyte-derived neutrophil chemotactic factor/interleukin-8

    International Nuclear Information System (INIS)

    Grob, P.M.; David, E.; Warren, T.C.; DeLeon, R.P.; Farina, P.R.; Homon, C.A.

    1990-01-01

    Monocyte-derived neutrophil chemotactic factor/interleukin-8 (MDNCF/IL-8) is an 8,000-dalton protein produced by monocytes which exhibits activity as a chemoattractant for neutrophils with maximal activity achieved at a concentration of 50 ng/ml. This polypeptide has been iodinated by chloramine-T methodology (350 Ci/mM), and specific receptors for MDNCF/IL-8 have been detected on human neutrophils, U937 cells, THP-1 cells, and dimethyl sulfoxide-differentiated HL-60 cells. The binding of MDNCF/IL-8 to human neutrophils is not inhibited by interleukin-1 alpha, tumor necrosis factor-alpha, insulin, or epidermal growth factor. In addition, chemoattractants such as C5a, fMet-Leu-Phe, leukotriene B4, and platelet-activating factor fail to inhibit binding, suggesting that MDNCF/IL-8 utilizes a unique receptor. The receptor for MDNCF/IL-8 is apparently glycosylated since ligand binding is inhibited by the presence of wheat germ agglutinin, a lectin with a binding specificity for N-acetylglucosamine and neuraminic acid. Steady state binding experiments indicate Kd values of 4 and 0.5 nM and receptor numbers of 75,000 and 7,400 for human neutrophils and differentiated HL-60 cells, respectively. 125I-MDNCF/IL-8 bound to human neutrophils is rapidly internalized and subsequently released from cells as trichloroacetic acid-soluble radioactivity. Affinity labeling experiments suggest that the human neutrophil MDNCF/IL-8 receptor exhibits a mass of approximately 58,000 daltons

  13. Association of interleukin-1 receptor antagonist VNTR polymorphism and risk of pre-eclampsia in southeast Iranian population.

    Science.gov (United States)

    Salimi, Saeedeh; Mohammadoo-Khorasani, Milad; Mousavi, Mahdieh; Yaghmaei, Minoo; Mokhtari, Mojgan; Farajian-Mashhadi, Farzaneh

    2016-02-01

    Pre-eclampsia (PE) is an obstetric disorder that may result in maternal and neonatal mortality and morbidity. Growing evidence indicates that cytokines, such as interleukins, are involved in the pathogenesis of this complication. Hence the current study aimed to assess the possible association between interleukin-1 receptor antagonist (IL-1Ra) VNTR polymorphism, and PE susceptibility in southeast Iranian women. The IL-Ra VNTR polymorphism was evaluated in 192 PE women and 186 age-matched normotensive pregnant women by the polymerase chain reaction method. The frequency of the A2 allele and the A2A2 genotype of IL-Ra VNTR polymorphism was significantly lower in PE patients compared to controls: therefore, A2 allele may play a protective role in PE development (odds ratio = 0.13 95% CI, [0.04-0.03]; P VNTR polymorphism and severity of the disease. The A2 allele of the IL-Ra VNTR polymorphism could be a protective factor for PE susceptibility. © 2015 Japan Society of Obstetrics and Gynecology.

  14. Minimally-invasive Sampling of Interleukin-1α and Interleukin-1 Receptor Antagonist from the Skin: A Systematic Review of In vivo Studies in Humans.

    Science.gov (United States)

    Falcone, Denise; Spee, Pieter; van de Kerkhof, Peter C M; van Erp, Piet E J

    2017-10-02

    Interleukin-1α (IL-1α) and its receptor antagonist IL-1RA play a pivotal role in skin homeostasis and disease. Although the use of biopsies to sample these cytokines from human skin is widely employed in dermatological practice, knowledge about less invasive, in vivo sampling methods is scarce. The aim of this study was to provide an overview of such methods by systematically reviewing studies in Medline, EMBASE, Web of Science and Cochrane Library using combinations of the terms "IL-1α", IL-1RA", "skin", "human", including all possible synonyms. Quality was assessed using the STrengthening the Reporting of OBservational studies in Epidemiology (STROBE) checklist. The search, performed on 14 October 2016, revealed 10 different sampling methods, with varying degrees of invasiveness and wide application spectrum, including assessment of both normal and diseased skin, from several body sites. The possibility to sample quantifiable amounts of cytokines from human skin with no or minimal discomfort holds promise for linking clinical outcomes to molecular profiles of skin inflammation.

  15. Divergent responses to thermogenic stimuli in BAT and subcutaneous adipose tissue from interleukin 18 and interleukin 18 receptor 1-deficient mice.

    Science.gov (United States)

    Pazos, Patricia; Lima, Luis; Tovar, Sulay; González-Touceda, David; Diéguez, Carlos; García, María C

    2015-12-10

    Brown and beige adipocytes recruitment in brown (BAT) or white adipose tissue, mainly in the inguinal fat pad (iWAT), meet the need for temperature adaptation in cold-exposure conditions and protect against obesity in face of hypercaloric diets. Using interleukin18 (Il18) and Il18 receptor 1- knockout (Il18r1-KO) mice, this study aimed to investigate the role of IL18 signaling in BAT and iWAT activation and thermogenesis under both stimuli. Il18-KO, extremely dietary obesity-prone as previously described, failed to develop diet-induced thermogenesis as assessed by BAT and iWAT Ucp1 mRNA levels. Overweight when fed standard chow but not HFD, HFD-fed Il18r1-KO mice exhibited increased iWAT Ucp1 gene expression. Energy expenditure was reduced in pre-obese Il18r1-KO mice and restored upon HFD-challenge. Cold exposure lead to similar results; Il18r1-KO mice were protected against acute body temperature drop, displaying a more brown-like structure, alternative macrophage activation and thermogenic gene expression in iWAT than WT controls. Opposite effects were observed in Il18-KO mice. Thus, Il18 and Il18r1 genetic ablation disparate effects on energy homeostasis are likely mediated by divergent BAT responses to thermogenic stimuli as well as iWAT browning. These results suggest that a more complex receptor-signaling system mediates the IL18 adipose-tissue specific effects in energy expenditure.

  16. Determination of sites of U50,488H-promoted phosphorylation of the mouse κ opioid receptor (KOPR): disconnect between KOPR phosphorylation and internalization.

    Science.gov (United States)

    Chen, Chongguang; Chiu, Yi-Ting; Wu, Wenman; Huang, Peng; Mann, Anika; Schulz, Stefan; Liu-Chen, Lee-Yuan

    2016-02-15

    Phosphorylation sites of KOPR (κ opioid receptor) following treatment with the selective agonist U50,488H {(-)(trans)-3,4-dichloro-N-methyl-N-[2-(1-pyrrolidiny)cyclo-hexyl]benzeneacetamide} were identified after affinity purification, SDS/PAGE, in-gel digestion with Glu-C and HPLC-MS/MS. Single- and double-phosphorylated peptides were identified containing phosphorylated Ser(356), Thr(357), Thr(363) and Ser(369) in the C-terminal domain. Antibodies were generated against three phosphopeptides containing pSer(356)/pThr(357), pThr(363) and pSer(369) respectively, and affinity-purified antibodies were found to be highly specific for phospho-KOPR. U50,488H markedly enhanced staining of the KOPR by pThr(363)-, pSer(369)- and pSer(356)/pThr(357)-specific antibodies in immunoblotting, which was blocked by the selective KOPR antagonist norbinaltorphimine. Ser(369) phosphorylation affected Thr(363) phosphorylation and vice versa, and Thr(363) or Ser(369) phosphorylation was important for Ser(356)/Thr(357) phosphorylation, revealing a phosphorylation hierarchy. U50,488H, but not etorphine, promoted robust KOPR internalization, although both were full agonists. U50,488H induced higher degrees of phosphorylation than etorphine at Ser(356)/Thr(357), Thr(363) and Ser(369) as determined by immunoblotting. Using SILAC (stable isotope labelling by amino acids in cell culture) and HPLC-MS/MS, we found that, compared with control (C), U50,488H (U) and etorphine (E) KOPR promoted single phosphorylation primarily at Thr(363) and Ser(369) with U/E ratios of 2.5 and 2 respectively. Both induced double phosphorylation at Thr(363)+Ser(369) and Thr(357)+Ser(369) with U/E ratios of 3.3 and 3.4 respectively. Only U50,488H induced triple phosphorylation at Ser(356)+Thr(357)+Ser(369). An unphosphorylated KOPR-(354-372) fragment containing all of the phosphorylation sites was detected with a C/E/U ratio of 1/0.7/0.4, indicating that ∼60% and ∼30% of the mouse KOPR are phosphorylated

  17. Opium addiction increases interleukin 1 receptor antagonist (IL-1Ra) in the coronary artery disease patients.

    Science.gov (United States)

    Saadat, Habibollah; Ziai, Seyed Ali; Ghanemnia, Maryam; Namazi, Mohammad Hasan; Safi, Morteza; Vakili, Hosein; Dabbagh, Ali; Gholami, Omid

    2012-01-01

    There is evidence that opium addiction has immunosuppressant effects. Coronary artery disease (CAD) is a condition resulted from atherosclerosis which is dependent on the immune response. To evaluate plasma levels of interleukin-6 and interleukin-1Ra in 30 patients with three-vessel coronary artery disease, ejection fraction of more than 35% and to evaluate their changes after prognostic treadmill test in 15 opium addicted and 15 non-addicted patients. The participants underwent prognostic treadmill test and plasma levels of interleukin-6 (IL-6) and interleukin-1Ra (IL-1Ra) were evaluated with ELISA method before, just after and 4 hours after the test. IL-1Ra (2183 pg/ml) tended to decrease over time in the opium addicted group (1372 pg/ml after prognostic treadmill test and 1034 pg/ml 4 hours after that), although such decrease did not reach the statistical significance. IL-1Ra levels were significantly higher in opium addicted than in non addicted patients. Opium addiction had no significant effect on IL-6 changes. Consumption of opium in CAD patients is associated with higher IL-1Ra levels.

  18. Opium addiction increases interleukin 1 receptor antagonist (IL-1Ra in the coronary artery disease patients.

    Directory of Open Access Journals (Sweden)

    Habibollah Saadat

    Full Text Available BACKGROUND: There is evidence that opium addiction has immunosuppressant effects. Coronary artery disease (CAD is a condition resulted from atherosclerosis which is dependent on the immune response. PURPOSE: To evaluate plasma levels of interleukin-6 and interleukin-1Ra in 30 patients with three-vessel coronary artery disease, ejection fraction of more than 35% and to evaluate their changes after prognostic treadmill test in 15 opium addicted and 15 non-addicted patients. METHODS: The participants underwent prognostic treadmill test and plasma levels of interleukin-6 (IL-6 and interleukin-1Ra (IL-1Ra were evaluated with ELISA method before, just after and 4 hours after the test. RESULTS: IL-1Ra (2183 pg/ml tended to decrease over time in the opium addicted group (1372 pg/ml after prognostic treadmill test and 1034 pg/ml 4 hours after that, although such decrease did not reach the statistical significance. IL-1Ra levels were significantly higher in opium addicted than in non addicted patients. Opium addiction had no significant effect on IL-6 changes. CONCLUSION: Consumption of opium in CAD patients is associated with higher IL-1Ra levels.

  19. Synthetic alleles at position 121 define a functional domain of human interleukin-1 beta.

    Science.gov (United States)

    Ambrosetti, D C; Palla, E; Mirtella, A; Galeotti, C; Solito, E; Navarra, P; Parente, L; Melli, M

    1996-06-01

    The non-conservative substitution of the tyrosine residue at position 121 of human interleukin-1 beta (IL-1 beta) generates protein mutants showing strong reduction of the capacity to induce (a) prostaglandin E2 (PGE2) release from fibroblasts and smooth muscle cells, (b) murine T-cells proliferation and (c) activation of interleukin-6 (IL-6) gene expression. It is generally accepted that these functions are mediated by the type-I interleukin-1 receptor (IL-1RI). However, the mutant proteins maintain the binding affinity to the types-I and II IL-1 receptors, which is the same as the control IL-1 beta, suggesting that this amino acid substitution does not alter the structure of the molecule, except locally. Thus we have identified a new functional site of IL-1 beta different from the known receptor binding region, responsible for fundamental IL-1 beta functions. Moreover, we show that the same mutants maintain at least two hypothalamic functions, that is, the in vitro short-term PGE2 release from rat hypothalamus and the induction of fever in rabbits. This result suggests that there is yet another site of the molecule responsible for the hypothalamic functions, implying that multiple active sites on the IL-1 beta molecule, possibly binding to more than one receptor chain, trigger different signals.

  20. A highly phosphorylated subpopulation of insulin-like growth factor II/mannose 6-phosphate receptors is concentrated in a clathrin-enriched plasma membrane fraction

    International Nuclear Information System (INIS)

    Corvera, S.; Folander, K.; Clairmont, K.B.; Czech, M.P.

    1988-01-01

    Insulin-like growth factor II (IGF-II)/mannose 6-phosphate (Man-6-P) receptors immunoprecipitated from purified plasma membranes of 32 P-labeled rat adipocytes are markedly heterogenous in their phosphorylation state. Approximately 80% of the plasma membrane receptors are solubilized in 1% (vol/vol) Triton X-100 and are phosphorylated on serine residues at a stoichiometry of ∼ 0.1-0.2 mol of phosphate per mol of receptor. In contrast, 15-20% of the receptors are Triton X-100-insoluble and are phosphorylated on serine and threonine residues at ∼ 4 or 5 mol of phosphate per mol of receptor. This Triton X-100-insoluble membrane subfraction contains only 5% of the total plasma membrane protein and yet contains all of the clathrin heavy chain associated with plasma membrane. Based on the relative yields of protein in the detergent-insoluble material, IGF-II/Man-6-P receptors are concentrated ∼ 3-fold in this clathrin-enriched subfraction. Taken together, these results indicate that insulin decreases the phosphorylation state of a highly phosphorylated subpopulation of IGF-II/Man-6-P receptors on the plasma membrane. In addition, insulin action may prevent the concentration of these receptors in a clathrin-enriched membrane subfraction

  1. Ghrelin upregulates the phosphorylation of the GluN2B subunit of the NMDA receptor by activating GHSR1a and Fyn in the rat hippocampus.

    Science.gov (United States)

    Berrout, Liza; Isokawa, Masako

    2018-01-01

    Ghrelin and its receptor GHSR1a have been shown to exert numerous physiological functions in the brain, in addition to the well-established orexigenic role in the hypothalamus. Earlier work indicated that ghrelin stimulated the phosphorylation of the GluN1 subunit of the NMDA receptor (NMDAR) and enhanced synaptic transmission in the hippocampus. In the present study, we report that the exogenous application of ghrelin increased GluN2B phosphorylation. This increase was independent of GluN2B subunit activity or NMDAR channel activity. However, it depended on the activation of GHSR1a and Fyn as it was blocked by D-Lys3-GHRP-6 and PP2, respectively. Inhibitors for G-protein-regulated second messengers, such as Rp-cAMP, H89, TBB, ryanodine, and thapsigargin, unexpectedly enhanced GluN2B phosphorylation, suggesting that cAMP, PKA, casein kinase II, and cytosolic calcium signaling may oppose to the effect of ghrelin on the phosphorylation of GluN2B. Our findings suggest that 1) GluN2B is likely a molecular target of ghrelin and GHSR1a-driven signaling cascades, and 2) the ghrelin-mediated phosphorylation of GluN2B depends on Fyn activation under complex negative regulation by other second messengers. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. M1 muscarinic receptor facilitates cognitive function by interplay with AMPA receptor GluA1 subunit.

    Science.gov (United States)

    Zhao, Lan-Xue; Ge, Yan-Hui; Xiong, Cai-Hong; Tang, Ling; Yan, Ying-Hui; Law, Ping-Yee; Qiu, Yu; Chen, Hong-Zhuan

    2018-03-06

    M1 muscarinic acetylcholine receptors (M1 mAChRs) are the most abundant muscarinic receptors in the hippocampus and have been shown to have procognitive effects. AMPA receptors (AMPARs), an important subtype of ionotropic glutamate receptors, are key components in neurocognitive networks. However, the role of AMPARs in procognitive effects of M1 mAChRs and how M1 mAChRs affect the function of AMPARs remain poorly understood. Here, we found that basal expression of GluA1, a subunit of AMPARs, and its phosphorylation at Ser845 were maintained by M1 mAChR activity. Activation of M1 mAChRs promoted membrane insertion of GluA1, especially to postsynaptic densities. Impairment of hippocampus-dependent learning and memory by antagonism of M1 mAChRs paralleled the reduction of GluA1 expression, and improvement of learning and memory by activation of M1 mAChRs was accompanied by the synaptic insertion of GluA1 and its increased phosphorylation at Ser845. Furthermore, abrogation of phosphorylation of Ser845 residue of GluA1 ablated M1 mAChR-mediated improvement of learning and memory. Taken together, these results show a functional correlation of M1 mAChRs and GluA1 and the essential role of GluA1 in M1 mAChR-mediated cognitive improvement.-Zhao, L.-X., Ge, Y.-H., Xiong, C.-H., Tang, L., Yan, Y.-H., Law, P.-Y., Qiu, Y., Chen, H.-Z. M1 muscarinic receptor facilitates cognitive function by interplay with AMPA receptor GluA1 subunit.

  3. Sphingosine-1-Phosphate and the S1P3 Receptor Initiate Neuronal Retraction via RhoA/ROCK Associated with CRMP2 Phosphorylation

    Science.gov (United States)

    Quarta, Serena; Camprubí-Robles, Maria; Schweigreiter, Rüdiger; Matusica, Dusan; Haberberger, Rainer V.; Proia, Richard L.; Bandtlow, Christine E.; Ferrer-Montiel, Antonio; Kress, Michaela

    2017-01-01

    The bioactive lipid sphingosine-1-phosphate (S1P) is an important regulator in the nervous system. Here, we explored the role of S1P and its receptors in vitro and in preclinical models of peripheral nerve regeneration. Adult sensory neurons and motor neuron-like cells were exposed to S1P in an in vitro assay, and virtually all neurons responded with a rapid retraction of neurites and growth cone collapse which were associated with RhoA and ROCK activation. The S1P1 receptor agonist SEW2871 neither activated RhoA or neurite retraction, nor was S1P-induced neurite retraction mitigated in S1P1-deficient neurons. Depletion of S1P3 receptors however resulted in a dramatic inhibition of S1P-induced neurite retraction and was on the contrary associated with a significant elongation of neuronal processes in response to S1P. Opposing responses to S1P could be observed in the same neuron population, where S1P could activate S1P1 receptors to stimulate elongation or S1P3 receptors and retraction. S1P was, for the first time in sensory neurons, linked to the phosphorylation of collapsin response-mediated protein-2 (CRMP2), which was inhibited by ROCK inhibition. The improved sensory recovery after crush injury further supported the relevance of a critical role for S1P and receptors in fine-tuning axonal outgrowth in peripheral neurons. PMID:29066950

  4. Phosphorylation site dynamics of early T-cell receptor signaling

    DEFF Research Database (Denmark)

    Chylek, Lily A; Akimov, Vyacheslav; Dengjel, Jörn

    2014-01-01

    In adaptive immune responses, T-cell receptor (TCR) signaling impacts multiple cellular processes and results in T-cell differentiation, proliferation, and cytokine production. Although individual protein-protein interactions and phosphorylation events have been studied extensively, we lack...... that diverse dynamic patterns emerge within seconds. We detected phosphorylation dynamics as early as 5 s and observed widespread regulation of key TCR signaling proteins by 30 s. Development of a computational model pointed to the presence of novel regulatory mechanisms controlling phosphorylation of sites...... a systems-level understanding of how these components cooperate to control signaling dynamics, especially during the crucial first seconds of stimulation. Here, we used quantitative proteomics to characterize reshaping of the T-cell phosphoproteome in response to TCR/CD28 co-stimulation, and found...

  5. Distinct phosphorylation sites on the ghrelin receptor, GHSR1a, establish a code that determines the functions of ß-arrestins

    Science.gov (United States)

    Bouzo-Lorenzo, Monica; Santo-Zas, Icía; Lodeiro, Maria; Nogueiras, Rubén; Casanueva, Felipe F.; Castro, Marian; Pazos, Yolanda; Tobin, Andrew B; Butcher, Adrian J.; Camiña, Jesús P.

    2016-01-01

    The growth hormone secretagogue receptor, GHSR1a, mediates the biological activities of ghrelin, which includes the secretion of growth hormone, as well as the stimulation of appetite, food intake and maintenance of energy homeostasis. Mapping phosphorylation sites on GHSR1a and knowledge of how these sites control specific functional consequences unlocks new strategies for the development of therapeutic agents targeting individual functions. Herein, we have identified the phosphorylation of different sets of sites within GHSR1a which engender distinct functionality of ß-arrestins. More specifically, the Ser362, Ser363 and Thr366 residues at the carboxyl-terminal tail were primarily responsible for ß-arrestin 1 and 2 binding, internalization and ß-arrestin-mediated proliferation and adipogenesis. The Thr350 and Ser349 are not necessary for ß-arrestin recruitment, but are involved in the stabilization of the GHSR1a-ß-arrestin complex in a manner that determines the ultimate cellular consequences of ß-arrestin signaling. We further demonstrated that the mitogenic and adipogenic effect of ghrelin were mainly dependent on the ß-arrestin bound to the phosphorylated GHSR1a. In contrast, the ghrelin function on GH secretion was entirely mediated by G protein signaling. Our data is consistent with the hypothesis that the phosphorylation pattern on the C terminus of GHSR1a determines the signaling and physiological output. PMID:26935831

  6. Adaptor Protein Complex-2 (AP-2) and Epsin-1 Mediate Protease-activated Receptor-1 Internalization via Phosphorylation- and Ubiquitination-dependent Sorting Signals*

    Science.gov (United States)

    Chen, Buxin; Dores, Michael R.; Grimsey, Neil; Canto, Isabel; Barker, Breann L.; Trejo, JoAnn

    2011-01-01

    Signaling by protease-activated receptor-1 (PAR1), a G protein-coupled receptor (GPCR) for thrombin, is regulated by desensitization and internalization. PAR1 desensitization is mediated by β-arrestins, like most classic GPCRs. In contrast, internalization of PAR1 occurs through a clathrin- and dynamin-dependent pathway independent of β-arrestins. PAR1 displays two modes of internalization. Constitutive internalization of unactivated PAR1 is mediated by the clathrin adaptor protein complex-2 (AP-2), where the μ2-adaptin subunit binds directly to a tyrosine-based motif localized within the receptor C-tail domain. However, AP-2 depletion only partially inhibits agonist-induced internalization of PAR1, suggesting a function for other clathrin adaptors in this process. Here, we now report that AP-2 and epsin-1 are both critical mediators of agonist-stimulated PAR1 internalization. We show that ubiquitination of PAR1 and the ubiquitin-interacting motifs of epsin-1 are required for epsin-1-dependent internalization of activated PAR1. In addition, activation of PAR1 promotes epsin-1 de-ubiquitination, which may increase its endocytic adaptor activity to facilitate receptor internalization. AP-2 also regulates activated PAR1 internalization via recognition of distal C-tail phosphorylation sites rather than the canonical tyrosine-based motif. Thus, AP-2 and epsin-1 are both required to promote efficient internalization of activated PAR1 and recognize discrete receptor sorting signals. This study defines a new pathway for internalization of mammalian GPCRs. PMID:21965661

  7. Significance of the interleukin-1 receptor antagonist/interleukin-1 beta ratio as a prognostic factor in patients with pulmonary sarcoidosis.

    Science.gov (United States)

    Mikuniya, T; Nagai, S; Takeuchi, M; Mio, T; Hoshino, Y; Miki, H; Shigematsu, M; Hamada, K; Izumi, T

    2000-01-01

    Various factors such as serum angiotensin-converting enzyme (sACE) activity, bronchoalveolar lavage (BAL) fluid lymphocyte percent, CD4/CD8 ratio, and shadows on chest radiograph have been identified as indexes of disease activity in patients with sarcoidosis. However, it remains to be confirmed whether these factors can predict clinical outcomes. To examine whether the interleukin-1 receptor antagonist (IL-1ra)/IL-1 beta ratio can predict the clinical course, we prospectively followed the clinical courses of 30 patients with pulmonary sarcoidosis 4 years after measurement of immunoreactive amounts of IL-1ra or IL-1 beta in the culture supernatants obtained from BAL fluid macrophages. Immunoreactive amounts of IL-1ra or IL-1 beta were measured using ELISA. Changes in pulmonary function, sACE activity, and shadows on chest radiographs during observation periods were evaluated as markers of changes in disease activity. We found that the patients whose shadows on chest radiographs showed improvement had a higher molar IL-1ra/IL-1 beta ratio than the patients whose shadows persistently remained 4 years after BAL examination (p sACE activity at the time of the last observation to sACE activity at the time of BAL (sACE(LAST)/sACE(BAL), p sACE(LAST)/sACE(BAL) ratio was significantly lower in patients whose shadows on chest radiographs decreased than in those whose shadows remained unchanged (p < 0.005). The IL-1ra/IL-1 beta ratio in the BAL fluid macrophage culture supernatants in patients with pulmonary sarcoidosis could be a useful marker in predicting the persistence of granulomatous lesions (chronicity). Copyright 2000 S. Karger AG, Basel

  8. Interleukin-1 and cutaneous inflammation: a crucial link between innate and acquired immunity.

    Science.gov (United States)

    Murphy, J E; Robert, C; Kupper, T S

    2000-03-01

    As our primary interface with the environment, the skin is constantly subjected to injury and invasion by pathogens. The fundamental force driving the evolution of the immune system has been the need to protect the host against overwhelming infection. The ability of T and B cells to recombine antigen receptor genes during development provides an efficient, flexible, and powerful immune system with nearly unlimited specificity for antigen. The capacity to expand subsets of antigen-specific lymphocytes that become activated by environmental antigens (memory response) is termed "acquired" immunity. Immunologic memory, although a fundamental aspect of mammalian biology, is a relatively recent evolutionary event that permits organisms to live for years to decades. "Innate" immunity, mediated by genes that remain in germ line conformation and encode for proteins that recognize conserved structural patterns on microorganisms, is a much more ancient system of host defense. Defensins and other antimicrobial peptides, complement and opsonins, and endocytic receptors are all considered components of the innate immune system. None of these, however, are signal-transducing receptors. Most recently, a large family of cell surface receptors that mediate signaling through the NF-kappaB transcription factor has been identified. This family of proteins shares striking homology with plant and Drosophila genes that mediate innate immunity. In mammals, this family includes the type I interleukin-1 receptor, the interleukin-18 receptor, and a growing family of Toll-like receptors, two of which were recently identified as signal-transducing receptors for bacterial endotoxin. In this review, we discuss how interleukin-1 links the innate and acquired immune systems to provide synergistic host defense activities in skin.

  9. Prokineticin-1 (PROK1) modulates interleukin (IL)-11 expression via prokineticin receptor 1 (PROKR1) and the calcineurin/NFAT signalling pathway.

    Science.gov (United States)

    Cook, Ian H; Evans, Jemma; Maldonado-Pérez, David; Critchley, Hilary O; Sales, Kurt J; Jabbour, Henry N

    2010-03-01

    Prokineticin-1 (PROK1) is a multifunctional secreted protein which signals via the G-protein coupled receptor, PROKR1. Previous data from our laboratory using a human genome survey microarray showed that PROK1-prokineticin receptor 1 (PROKR1) signalling regulates numerous genes important for establishment of early pregnancy, including the cytokine interleukin (IL)-11. Here, we have shown that PROK1-PROKR1 induces the expression of IL-11 in PROKR1 Ishikawa cells and first trimester decidua via the calcium-calcineurin signalling pathway in a guanine nucleotide-binding protein (G(q/11)), extracellular signal-regulated kinases, Ca(2+) and calcineurin-nuclear factor of activated T cells dependent manner. Conversely, treatment of human decidua with a lentiviral miRNA to abolish endogenous PROK1 expression results in a significant reduction in IL-11 expression and secretion. Importantly, we have also shown a regulatory role for the regulator of calcineurin 1 isoform 4 (RCAN1-4). Overexpression of RCAN1-4 in PROKR1 Ishikawa cells using an adenovirus leads to a reduction in PROK1 induced IL-11 indicating that RCAN1-4 is a negative regulator in the calcineurin-mediated signalling to IL-11. Finally, we have shown the potential for both autocrine and paracrine signalling in the human endometrium by co-localizing IL-11, IL-11Ralpha and PROKR1 within the stromal and glandular epithelial cells of non-pregnant endometrium and first trimester decidua. Overall we have identified and characterized the signalling components of a novel PROK1-PROKR1 signalling pathway regulating IL-11.

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

    DEFF Research Database (Denmark)

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

    1995-01-01

    and a reduction of GH-dependent phosphorylation of the full-length receptor. Consistent with Tyr333 and/or Tyr338 serving as substrates of JAK2, these substitutions resulted in a loss of tyrosyl phosphorylation of truncated receptor in an in vitro kinase assay using substantially purified GH.GHR.JAK2 complexes...

  11. The IRS-1 signaling system.

    Science.gov (United States)

    Myers, M G; Sun, X J; White, M F

    1994-07-01

    Insulin-receptor substrate 1 (IRS-1) is a principal substrate of the receptor tyrosine kinase for insulin and insulin-like growth factor 1, and a substrate for a tyrosine kinase activated by interleukin 4. IRS-1 undergoes multisite tyrosine phosphorylation and mediates downstream signals by 'docking' various proteins that contain Src homology 2 domains. IRS-1 appears to be a unique molecule; however, 4PS, a protein found mainly in hemopoietic cells, may represent another member of this family.

  12. γ-aminobutyric acidA (GABAA) receptor regulates ERK1/2 phosphorylation in rat hippocampus in high doses of Methyl Tert-Butyl Ether (MTBE)-induced impairment of spatial memory

    International Nuclear Information System (INIS)

    Zheng Gang; Zhang Wenbin; Zhang Yun; Chen Yaoming; Liu Mingchao; Yao Ting; Yang Yanxia; Zhao Fang; Li Jingxia; Huang Chuanshu; Luo Wenjing; Chen Jingyuan

    2009-01-01

    Experimental and occupational exposure to Methyl Tert-Butyl Ether (MTBE) has been reported to induce neurotoxicological and neurobehavioral effects, such as headache, nausea, dizziness, and disorientation, etc. However, the molecular mechanisms involved in MTBE-induced neurotoxicity are still not well understood. In the present study, we investigated the effects of MTBE on spatial memory and the expression and function of GABA A receptor in the hippocampus. Our results demonstrated that intraventricular injection of MTBE impaired the performance of the rats in a Morris water maze task, and significantly increased the expression of GABA A receptor α1 subunit in the hippocampus. The phosphorylation of ERK1/2 decreased after the MTBE injection. Furthermore, the decreased ability of learning and the reduction of phosphorylated ERK1/2 level of the MTBE-treated rats was partly reversed by bicuculline injected 30 min before the training. These results suggested that MTBE exposure could result in impaired spatial memory. GABA A receptor may play an important role in the MTBE-induced impairment of learning and memory by regulating the phosphorylation of ERK in the hippocampus.

  13. Phorbol ester induced phosphorylation of the estrogen receptor in intact MCF-7 human breast cancer cells

    International Nuclear Information System (INIS)

    Knabbe, C.; Lippman, M.E.; Greene, G.L.; Dickson, R.B.

    1986-01-01

    Recent studies with a variety of cellular receptors have shown that phorbol ester induced phosphorylation modulates ligand binding and function. In this study the authors present direct evidence that the estrogen receptor in MCF-7 human breast cancer cells is a phosphoprotein whose phosphorylation state can be enhanced specifically by phorbol-12-myristate-13-acetate (PMA). Cells were cultured to 6h in the presence of [ 32 P]-orthophosphate. Whole cell extracts were immunoprecipitated with a monoclonal antibody (D58) against the estrogen receptor and subjected to SDS-polyacrylamide electrophoresis. Autoradiography showed a specific band in the region of 60-62 kDa which was significantly increased in preparations from PMA treated cells. Phospho-amino acid analysis demonstrated specific phosphorylation of serine and threonine residues. Cholera toxin or forskolin did not change the phosphorylation state of this protein. In a parallel binding analysis PMA led to a rapid decrease of estrogen binding sites. The estrogen induction of both progesterone receptors and growth in semisolid medium was blocked by PMA, whereas the estrogen induction of the 8kDa protein corresponding to the ps2 gene product and of the 52 kDa protein was not affected. In conclusion, phorbol esters can induce phosphorylation of the estrogen receptor. This process may be associated with the inactivation of certain receptor functions

  14. Nutrition, anthropometry, gastrointestinal dysfunction, and circulating levels of tumour necrosis factor alpha receptor I and interleukin-1 receptor antagonist in children during stem cell transplantation

    DEFF Research Database (Denmark)

    Andreassen, B. U.; Pærregaard, Anders; Michaelsen, Kim F.

    2008-01-01

    To evaluate anthropometry, nutrition and gastrointestinal dysfunction, and to characterize the relation between these parameters and the inflammatory activity evaluated by plasma levels of soluble tumour necrosis factor alpha receptor I (sTNFRI) and interleukin-1 receptor antagonist (IL-1Ra) levels...... during stem cell transplantation (SCT) in children. Clinical assessments and blood sampling were performed on days -3, 0, +7, +15 and +31 in eight children undergoing SCT. Energy intake, anthropometry, gastrointestinal dysfunction (WHO toxicity score) and sTNFRI and IL-1Ra were evaluated. The energy...... intake was below recommended levels. There was a loss of lean body mass (arm muscle area)(median, 2031 mm(2) (day -3) vs 1477 mm(2) (day 31); p = 0.04), and of fat mass (arm fat area) (791 mm(2) (day -3) vs 648 mm(2) (day +31); p = 0.04). sTNFRI was elevated throughout the course of transplantation...

  15. Human Interleukine-1 receptor antagonist:Cloning, Expression and Optimization in E.coli Host

    Directory of Open Access Journals (Sweden)

    Gh. Barati

    2014-07-01

    Full Text Available Introduction & Objective: Interleukine-1 receptor antagonist (IL-1RA is a powerful anti-inflammatory cytokine which limits the biological effects of IL-1. Due to structural similarity between IL-1 and its antagonist, IL-1RA competitively binds to IL-1 receptor which leads to no signal transduction. Therefore , it is applied in the treatment of patients with inflammatory diseases such as Rheumatoid Arthritis. The aim of this study is cloning, expression and op-timization of IL-1RA in E. coli. Materials & Methods: In this experimental study synthetically prepared cDNA was amplified by PCR. After double digestion with NdeI and XhoI restriction enzymes, this gene was cloned in pET28a expression vector. Expression of desired gene was analyzed at RNA level by RT-PCR and at protein level by SDS-PAGE and followed by western blot to confirm SDS-PAGE results. Optimization of recombinant protein expression was performed in dif-ferent IPTG concentrations and harvesting times after induction. Results: The presence of gene in pET28a was determined by colony-PCR and confirmed by restriction digestion. Transcription of cloned gene and expression of high yield recombinant protein were shown by RT-PCR and SDS-PAGE, respectively. The result of SDS-PAGE was confirmed by western blot. Expression was optimized in different induction time and IPTG concentrations Conclusion: The result of this study demonstrated expression of this recombinant protein at high level in E.coli system by pET28a expression vector. This study also showed a direct as-sociation between the increased level of expression and time of induction . Therefore, an overnight induction time with 0.1 mM IPTG concentration is recommended for a high level expression. (Sci J Hamadan Univ Med Sci 2014; 21 (2:145-151

  16. Integrated regulation of AMPA glutamate receptor phosphorylation in the striatum by dopamine and acetylcholine.

    Science.gov (United States)

    Xue, Bing; Chen, Elton C; He, Nan; Jin, Dao-Zhong; Mao, Li-Min; Wang, John Q

    2017-01-01

    Dopamine (DA) and acetylcholine (ACh) signals converge onto protein kinase A (PKA) in medium spiny neurons of the striatum to control cellular and synaptic activities of these neurons, although underlying molecular mechanisms are less clear. Here we measured phosphorylation of the α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid receptor (AMPAR) at a PKA site (S845) as an indicator of AMPAR responses in adult rat brains in vivo to explore how DA and ACh interact to modulate AMPARs. We found that subtype-selective activation of DA D1 receptors (D1Rs), D2 receptors (D2Rs), or muscarinic M4 receptors (M4Rs) induced specific patterns of GluA1 S845 responses in the striatum. These defined patterns support a local multitransmitter interaction model in which D2Rs inhibited an intrinsic inhibitory element mediated by M4Rs to enhance the D1R efficacy in modulating AMPARs. Consistent with this, selective enhancement of M4R activity by a positive allosteric modulator resumed the cholinergic inhibition of D1Rs. In addition, D1R and D2R coactivation recruited GluA1 and PKA preferentially to extrasynaptic sites. In sum, our in vivo data support an existence of a dynamic DA-ACh balance in the striatum which actively modulates GluA1 AMPAR phosphorylation and trafficking. This article is part of the Special Issue entitled 'Ionotropic glutamate receptors'. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Identification of a new adapter protein that may link the common beta subunit of the receptor for granulocyte/macrophage colony-stimulating factor, interleukin (IL)-3, and IL-5 to phosphatidylinositol 3-kinase.

    Science.gov (United States)

    Jücker, M; Feldman, R A

    1995-11-17

    Binding of human granulocyte/macrophage colony-stimulating factor (hGM-CSF) to its receptor induces the rapid activation of phosphatidylinositol-3 kinase (PI 3-kinase). As hGM-CSF receptor (hGMR) does not contain a consensus sequence for binding of PI 3-kinase, hGMR must use a distinct mechanism for its association with and activation of PI 3-kinase. Here, we describe the identification of a tyrosine-phosphorylated protein of 76-85 kDa (p80) that associates with the common beta subunit of hGMR and with the SH2 domains of the p85 subunit of PI 3-kinase in hGM-CSF-stimulated cells. Src/Yes and Lyn were tightly associated with the p80.PI 3-kinase complex, suggesting that p80 and other phosphotyrosyl proteins present in the complex were phosphorylated by Src family kinases. Tyrosine phosphorylation of p80 was only detected in hGM-CSF or human interleukin-3-stimulated cells, suggesting that activation of p80 might be specific for signaling via the common beta subunit. We postulate that p80 functions as an adapter protein that may participate in linking the hGM-CSF receptor to the PI 3-kinase signaling pathway.

  18. IGF-I Stimulates Cooperative Interaction between the IGF-I Receptor and CSK Homologous Kinase that Regulates SHPS-1 Phosphorylation in Vascular Smooth Muscle Cells

    Science.gov (United States)

    Radhakrishnan, Yashwanth; Shen, Xinchun; Maile, Laura A.; Xi, Gang

    2011-01-01

    IGF-I plays an important role in smooth muscle cell proliferation and migration. In vascular smooth muscle cells cultured in 25 mm glucose, IGF-I stimulated a significant increase in Src homology 2 domain containing protein tyrosine phosphatase substrate-1 (SHPS-1) phosphorylation compared with 5 mm glucose and this increase was required for smooth muscle cell proliferation. A proteome-wide screen revealed that carboxyl-terminal SRC kinase homologous kinase (CTK) bound directly to phosphotyrosines in the SHPS-1 cytoplasmic domain. Because the kinase(s) that phosphorylates these tyrosines in response to IGF-I is unknown, we determined the roles of IGF-I receptor (IGF-IR) and CTK in mediating SHPS-1 phosphorylation. After IGF-I stimulation, CTK was recruited to IGF-IR and subsequently to phospho-SHPS-1. Expression of an IGF-IR mutant that eliminated CTK binding reduced CTK transfer to SHPS-1, SHPS-1 phosphorylation, and cell proliferation. IGF-IR phosphorylated SHPS-1, which provided a binding site for CTK. CTK recruitment to SHPS-1 resulted in a further enhancement of SHPS-1 phosphorylation. CTK knockdown also impaired IGF-I-stimulated SHPS-1 phosphorylation and downstream signaling. Analysis of specific tyrosines showed that mutation of tyrosines 428/452 in SHPS-1 to phenylalanine reduced SHPS-1 phosphorylation but allowed CTK binding. In contrast, the mutation of tyrosines 469/495 inhibited IGF-IR-mediated the phosphorylation of SHPS-1 and CTK binding, suggesting that IGF-IR phosphorylated Y469/495, allowing CTK binding, and that CTK subsequently phosphorylated Y428/452. Based on the above findings, we conclude that after IGF-I stimulation, CTK is recruited to IGF-IR and its recruitment facilitates CTK's subsequent association with phospho-SHPS-1. This results in the enhanced CTK transfer to SHPS-1, and the two kinases then fully phosphorylate SHPS-1, which is necessary for IGF-I stimulated cellular proliferation. PMID:21799000

  19. Interleukin-1β causes fluoxetine resistance in an animal model of epilepsy-associated depression.

    Science.gov (United States)

    Pineda, Eduardo A; Hensler, Julie G; Sankar, Raman; Shin, Don; Burke, Teresa F; Mazarati, Andréy M

    2012-04-01

    Depression represents a common comorbidity of epilepsy and is frequently resistant to selective serotonin reuptake inhibitors (SSRI). We tested the hypothesis that the SSRI resistance in epilepsy associated depression may be a result of a pathologically enhanced interleukin-1β (IL1-β) signaling, and consequently that the blockade of IL1-β may restore the effectiveness of SSRI. Epilepsy and concurrent depression-like impairments were induced in Wistar rats by pilocarpine status epilepticus (SE). The effects of the 2-week long treatment with fluoxetine, interleukin-1 receptor antagonist (IL-1ra), and their combination were examined using behavioral, biochemical, neuroendocrine, and autoradiographic assays. In post-SE rats, depression-like impairments included behavioral deficits indicative of hopelessness and anhedonia; the hyperactivity of the hypothalamo-pituitary-adrenocortical axis; the diminished serotonin output from raphe nucleus; and the upregulation of presynaptic serotonin 1-A (5-HT1A) receptors. Fluoxetine monotherapy exerted no antidepressant effects, whereas the treatment with IL-1ra led to the complete reversal of anhedonia and to a partial improvement of all other depressive impairments. Combined administration of fluoxetine and IL-1ra completely abolished all hallmarks of epilepsy-associated depressive abnormalities, with the exception of the hyperactivity of the hypothalamo-pituitary-adrenocortical axis, the latter remaining only partially improved. We propose that in certain forms of depression, including but not limited to depression associated with epilepsy, the resistance to SSRI may be driven by the pathologically enhanced interleukin-1β signaling and by the subsequent upregulation of presynaptic 5-HT1A receptors. In such forms of depression, the use of interleukin-1β blockers in conjunction with SSRI may represent an effective therapeutic approach.

  20. Interleukin-1 signaling is essential for host defense during murine pulmonary tuberculosis

    NARCIS (Netherlands)

    Juffermans, N. P.; Florquin, S.; Camoglio, L.; Verbon, A.; Kolk, A. H.; Speelman, P.; van Deventer, S. J.; van der Poll, T.

    2000-01-01

    Interleukin (IL)-1 signaling is required for the containment of infections with intracellular microorganisms, such as Listeria monocytogenes and Leishmania major. To determine the role of IL-1 in the host response to tuberculosis, we infected IL-1 type I receptor-deficient (IL-1R(-/-)) mice, in

  1. SP600125 Induces Src and Type I IGF Receptor Phosphorylation Independent of JNK

    Directory of Open Access Journals (Sweden)

    Qingbin Kong

    2014-09-01

    Full Text Available c-Jun N-terminal kinases (JNK are members of the mitogen-activated protein kinase (MAPK family that have important roles in signal transduction. The small molecule SP600125 is widely used in biochemical studies as a JNK inhibitor. However, recent studies indicate that SP600125 may also act independent of JNK. Here, we report that SP600125 can induce Src, type I insulin-like growth factor receptor (IGF-IR, Akt and Erk1/2 phosphorylation. Notably, these effects are independent of its inhibition of JNK. Inhibition of Src abrogates the stimulation of IGF-IR, Akt and Erk1/2 phosphorylation. IGF-IR knockdown blunts the induction of both Akt and Erk1/2 phosphorylation by SP600125. Moreover, combination of SP600125 and the Src inhibitor saracatinib synergistically inhibits cell proliferation. We conclude that SP600125 can activate Src-IGF-IR-Akt/Erk1/2 signaling pathways independent of JNK.

  2. Bisphenol-A rapidly enhanced passive avoidance memory and phosphorylation of NMDA receptor subunits in hippocampus of young rats

    International Nuclear Information System (INIS)

    Xu Xiaohong; Li Tao; Luo Qingqing; Hong Xing; Xie Lingdan; Tian Dong

    2011-01-01

    Bisphenol-A (BPA), an endocrine disruptor, is found to influence development of brain and behaviors in rodents. The previous study indicated that perinatal exposure to BPA impaired learning-memory and inhibited N-methyl-D-aspartate receptor (NMDAR) subunits expressions in hippocampus during the postnatal development in rats; and in cultured hippocampal neurons, BPA rapidly promotes dynamic changes in dendritic morphology through estrogen receptor-mediated pathway by concomitant phosphorylation of NMDAR subunit NR2B. In the present study, we examined the rapid effect of BPA on passive avoidance memory and NMDAR in the developing hippocampus of Sprague-Dawley rats at the age of postnatal day 18. The results showed that BPA or estradiol benzoate (EB) rapidly extended the latency to step down from the platform 1 h after footshock and increased the phosphorylation levels of NR1, NR2B, and mitogen-activated extracellular signal-regulated kinase (ERK) in hippocampus within 1 h. While 24 h after BPA or EB treatment, the improved memory and the increased phosphorylation levels of NR1, NR2B, ERK disappeared. Furthermore, pre-treatment with an estrogen receptors (ERs) antagonist, ICI182,780, or an ERK-activating kinase inhibitor, U0126, significantly attenuated EB- or BPA-induced phosphorylations of NR1, NR2B, and ERK within 1 h. These data suggest that BPA rapidly enhanced short-term passive avoidance memory in the developing rats. A non-genomic effect via ERs may mediate the modulation of the phosphorylation of NMDAR subunits NR1 and NR2B through ERK signaling pathway. - Highlights: → BPA rapidly extended the latency to step down from platform 1 h after footshock. → BPA rapidly increased pNR1, pNR2B, and pERK in hippocampus within 1 h. → ERs antagonist or MEK inhibitor attenuated BPA-induced pNR1, pNR2B, and pERK.

  3. H1 antihistamines in allergic rhinitis: The molecular pathways of interleukin and toll - like receptor systems

    Directory of Open Access Journals (Sweden)

    Jonny Karunia Fajar

    2016-03-01

    Full Text Available The complex interaction between inflammatory mediators in allergic rhinitis (AR is determined by the role of genetic polymorphisms, including interleukin (IL and toll-like receptor (TLR genes. This study aimed to discuss the effects of H1-antihistamines on IL and TLR systems. Several ILs involved in AR pathogenesis are: IL-4 (rs2243250, rs1800925, rs1801275, rs2227284, rs2070874, IL-6 (rs1800795, rs1800797, IL-10 (rs1800871, rs1800872, IL-12R (rs438421, IL-13 (rs1800925, rs20541, IL-17 (rs3819024, IL-18 (rs360721, rs360718, rs360717, rs187238, IL-23R (rs7517847, and IL-27 (rs153109, rs17855750. In the IL system, histamines stimulate the IL production in Type 2 helper T (Th2 cells through protein kinase A (PKA, janus kinase-signal transducer and activator of transcription (JAK-STAT pathway, and the activation of H1-histamine receptor and histidine decarboxylase (HDC genes. On contrary, antihistamines down-regulate the H1-histamine receptor gene expression through the transcription suppression of HDC and IL genes and suppress histamine basal signaling through the inverse agonistic activity. TLRs involved in AR pathogenesis are TLR2 (rs4696480, rs3804099, rs5743708, TLR4 (rs4986790, TLR6 (rs2381289, TLR7 (rs179008, rs5935438, TRL8 (rs2407992, rs5741883, rs17256081, rs4830805, rs3788935, rs178998, and TLR10 (rs11466651. In the TLR system, histamines trigger the TLR expression by stimulating interferon-γ (IFN-γ to up-regulate mast cells and by stimulating receptor-interacting protein (RIP to activate IκB kinase-β. Contrastingly, antihistamines suppress TIR-domain-containing adaptor protein inducing IFN-β (TRIF and RIP protein and thus inhibit the expression of TLR. In addition, several studies indicated that H1-antihistamines inhibit the IL and TLR systems indirectly.

  4. Molecular basis of a high affinity murine interleukin-5 receptor.

    OpenAIRE

    Devos, R; Plaetinck, G; Van der Heyden, J; Cornelis, S; Vandekerckhove, J; Fiers, W; Tavernier, J

    1991-01-01

    The mouse interleukin-5 receptor (mIL-5R) consists of two components one of which, the mIL-5R alpha-chain, binds mIL-5 with low affinity. Recently we demonstrated that monoclonal antibodies (Mabs) recognizing the second mIL-5R beta-chain, immunoprecipitate a p130-140 protein doublet which corresponds to the mIL-3R and the mIL-3R-like protein, the latter chain for which so far no ligand has been identified. In this study we show that a high affinity mIL-5R can be reconstituted on COS1 cells by...

  5. Carboxyl-terminal multi-site phosphorylation regulates internalization and desensitization of the human sst2 somatostatin receptor.

    Science.gov (United States)

    Lehmann, Andreas; Kliewer, Andrea; Schütz, Dagmar; Nagel, Falko; Stumm, Ralf; Schulz, Stefan

    2014-04-25

    The somatostatin receptor 2 (sst2) is the pharmacological target of somatostatin analogs that are widely used in the diagnosis and treatment of human neuroendocrine tumors. We have recently shown that the stable somatostatin analogs octreotide and pasireotide (SOM230) stimulate distinct patterns of sst2 receptor phosphorylation and internalization. Like somatostatin, octreotide promotes the phosphorylation of at least six carboxyl-terminal serine and threonine residues namely S341, S343, T353, T354, T356 and T359, which in turn leads to a robust receptor endocytosis. Unlike somatostatin, pasireotide stimulates a selective phosphorylation of S341 and S343 of the human sst2 receptor followed by a partial receptor internalization. Here, we show that exchange of S341 and S343 by alanine is sufficient to block pasireotide-driven internalization, whereas mutation of T353, T354, T356 and T359 to alanine is required to strongly inhibited both octreotide- and somatostatin-induced internalization. Yet, combined mutation of T353, T354, T356 and T359 is not sufficient to prevent somatostatin-driven β-arrestin mobilization and receptor desensitization. Replacement of all fourteen carboxyl-terminal serine and threonine residues by alanine completely abrogates sst2 receptor internalization and β-arrestin mobilization in HEK293 cells. Together, our findings demonstrate for the first time that agonist-selective sst2 receptor internalization is regulated by multi-site phosphorylation of its carboxyl-terminal tail. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Augmenter of liver regeneration causes different kinetics of ERK1/2 and Akt/PKB phosphorylation than EGF and induces hepatocyte proliferation in an EGF receptor independent and liver specific manner

    Energy Technology Data Exchange (ETDEWEB)

    Ilowski, Maren; Putz, Christine [Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany); Weiss, Thomas S. [Department of Surgery, University of Regensburg Hospital, Regensburg (Germany); Brand, Stephan [Department of Internal Medicine II, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany); Hengstler, Jan G. [Leibniz Research Centre for Working Environment and Human Factors, TU Dortmund University, Dortmund (Germany); Thasler, Wolfgang Erwin, E-mail: wolfgang.thasler@med.uni-muenchen.de [Department of Surgery, Ludwig-Maximilians-University of Munich Hospital Grosshadern, Munich (Germany)

    2010-04-16

    Background/Aim: Augmenter of liver regeneration (ALR) is a potent growth factor which supports liver regeneration in experimental animals. The aim of this study was to compare proliferation as well as the kinetics of ERK1/2 and Akt/PKB phosphorylation by recombinant human ALR (rhALR) and EGF in human hepatocytes and extrahepatic cells. Methods: Kinetics of ERK1/2 and Akt/PKB phosphorylation were determined in primary human hepatocytes (phh) after stimulation with rhALR and EGF. Induction of proliferation was analyzed in phh and several cell lines of hepatic and extrahepatic origin by the MTT and [{sup 3}H]-thymidine assay. Results: The kinetics of ERK phosphorylation showed clear differences, whereby rhALR caused a transient and EGF a permanent increase during the observation period of 60 min. For both, Akt and ERK phosphorylation, EGF caused a faster effect with maximal levels observed already after 2 min, whereas rhALR caused maximal phosphorylation between 10 and 15 min. Using the EGF receptor inhibitor AG1478 we provide evidence of an EGF receptor independent induction of proliferation by rhALR. Furthermore, rhALR induced proliferation only in phh and the human liver derived cell lines HepG2 and Chang. In contrast, EGF enhanced proliferation in all analyzed cell types including cell lines of colon, bronchial, pancreatic and gastric origin (SW480, BC1, L36PL and GC1). Conclusion: rhALR and EGF induce different kinetics of ERK and Akt phosphorylation in human hepatocytes. The mitogenic effect of rhALR is liver specific and seems to be at least partially independent from EGF receptor mediated signaling.

  7. Complex formation of EphB1/Nck/Caskin1 leads to tyrosine phosphorylation and structural changes of the Caskin1 SH3 domain

    Directory of Open Access Journals (Sweden)

    Pesti Szabolcs

    2012-11-01

    Full Text Available Abstract Background Scaffold proteins have an important role in the regulation of signal propagation. These proteins do not possess any enzymatic activity but can contribute to the formation of multiprotein complexes. Although scaffold proteins are present in all cell types, the nervous system contains them in the largest amount. Caskin proteins are typically present in neuronal cells, particularly, in the synapses. However, the signaling mechanisms by which Caskin proteins are regulated are largely unknown. Results Here we demonstrate that EphB1 receptor tyrosine kinase can recruit Caskin1 through the adaptor protein Nck. Upon activation of the receptor kinase, the SH2 domain of Nck binds to one of its tyrosine residues, while Nck SH3 domains interact with the proline-rich domain of Caskin1. Complex formation of the receptor, adaptor and scaffold proteins results in the tyrosine phosphorylation of Caskin1 on its SH3 domain. The phosphorylation sites were identified by mass-spectrometry as tyrosines 296 and 336. To reveal the structural consequence of this phosphorylation, CD spectroscopy was performed. This measurement suggests that upon tyrosine phosphorylation the structure of the Caskin1 SH3 domain changes significantly. Conclusion Taken together, we propose that the scaffold protein Caskin1 can form a complex with the EphB1 tyrosine kinase via the Nck protein as a linker. Complex formation results in tyrosine phosphorylation of the Caskin1 SH3 domain. Although we were not able to identify any physiological partner of the SH3 domain so far, we could demonstrate that phosphorylation on conserved tyrosine residues results in marked changes in the structure of the SH3 domain.

  8. Lipoxin A4 regulates expression of the estrogen receptor and inhibits 17β-estradiol induced p38 mitogen-activated protein kinase phosphorylation in human endometriotic stromal cells.

    Science.gov (United States)

    Chen, Shuo; Wu, Rong-Feng; Su, Lin; Zhou, Wei-Dong; Zhu, Mao-Bi; Chen, Qiong-Hua

    2014-07-01

    To study the role of lipoxin A4 (LXA4) in endometriosis. Molecular analysis in human samples and primary human endometriotic stromal cells (ESCs). University hospital. Forty-nine premenopausal women (30 patients with endometriosis and 19 controls). Normal and ectopic endometrial biopsies obtained during surgery performed during the proliferative phase of the menstrual cycle; ESCs used for in vitro studies. Levels of LXA4 measured by enzyme-linked immunosorbent assay (ELISA); mRNA levels of the estrogen receptor (ER), progestogen receptor (PR), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) quantified by quantitative reverse-transcription polymerase chain reaction (qRT-PCR); and p38 mitogen-activated protein kinase (p38 MAPK) phosphorylation evaluated by Western blotting. The LXA4 expression level decreased in ectopic tissue as well as ERα and PR, although the expression of ERβ increased in ectopic endometrium compared with the controls. Investigations with correlation analysis revealed the expression of LXA4 was positively correlated with ERα and negatively correlated with ERβ in vivo. Moreover, administering LXA4 could augment ERβ expression in ESCs and inhibit the 17β-estradiol-induced phosphorylation of p38 MAPK very likely through ERβ. Our findings indicate that LXA4 regulates ERβ expression and inhibits 17β-estradiol-induced phosphorylation of p38 MAPK, very likely through ERβ in ESCs. Copyright © 2014. Published by Elsevier Inc.

  9. Mangiferin inhibits lipopolysaccharide-induced production of interleukin-6 in human oral epithelial cells by suppressing toll-like receptor signaling.

    Science.gov (United States)

    Li, Hao; Wang, Qi; Chen, Xinmin; Ding, Yi; Li, Wei

    2016-11-01

    Oral epithelial cells have currently been found to play an important role in inflammatory modulation in periodontitis. Mangiferin is a natural glucosylxanthone with anti-inflammatory activity. The aim of this study was to investigate the regulatory effect of mangiferin on lipopolysaccharide (LPS)-induced production of proinflammatory cytokine interleukin-6 (IL-6) in oral epithelial cells and the underlying mechanisms. The levels of LPS-induced IL-6 production in OKF6/TERT-2 oral keratinocytes were detected using enzyme-linked immunosorbent assay (ELISA). The expression of Toll-like receptor (TLR) 2 and TLR4 was determined using western blot analysis. And the phosphorylation of TLR downstream nuclear factor-κB (NF-κB), p38 mitogen-activated protein kinase (p38 MAPK) and c-Jun N-terminal kinase (JNK) was examined using cell-based protein phosphorylation ELISA kits. We found that mangiferin reduced LPS-upregulated IL-6 production in OKF6/TERT-2 cells. Additionally, mangiferin inhibited LPS-induced TLR2 and TLR4 overexpression, and suppressed the phosphorylation of NF-κB, p38 MAPK and JNK. Moreover, mangiferin repressed IL-6 production and TLR signaling activation in a dose-dependent manner after 24h treatment. Mangiferin decreases LPS-induced production of IL-6 in human oral epithelial cells by suppressing TLR signaling, and this glucosylxanthone may have potential for the treatment of periodontitis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. The protein pheromone Er-1 of the ciliate Euplotes raikovi stimulates human T-cell activity: Involvement of interleukin-2 system

    Energy Technology Data Exchange (ETDEWEB)

    Cervia, Davide, E-mail: d.cervia@unitus.it [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Catalani, Elisabetta; Belardinelli, Maria Cristina [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Perrotta, Cristiana [Department of Biomedical and Clinical Sciences, “Luigi Sacco” University Hospital, University of Milan, Milano (Italy); Picchietti, Simona [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Alimenti, Claudio [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy); Casini, Giovanni; Fausto, Anna Maria [Department for Innovation in Biological, Agro-food and Forest systems (DIBAF), University of Tuscia, Viterbo (Italy); Vallesi, Adriana [Department of Environmental and Natural Sciences, University of Camerino, Camerino (Italy)

    2013-02-01

    Water-soluble protein signals (pheromones) of the ciliate Euplotes have been supposed to be functional precursors of growth factors and cytokines that regulate cell–cell interaction in multi-cellular eukaryotes. This work provides evidence that native preparations of the Euplotes raikovi pheromone Er-1 (a helical protein of 40 amino acids) specifically increases viability, DNA synthesis, proliferation, and the production of interferon-γ, tumor necrosis factor-α, interleukin (IL)-1β, IL-2, and IL-13 in human Jurkat T-cells. Also, Er-1 significantly decreases the mRNA levels of the β and γ subunits of IL-2 receptor (IL-2R), while the mRNA levels of the α subunit appeared to be not affected. Jurkat T-cell treatments with Er-1 induced the down-regulation of the IL-2Rα subunit by a reversible and time-dependent endocytosis, and increased the levels of phosphorylation of the extracellular signal-regulated kinases (ERK). The cell-type specificity of these effects was supported by the finding that Er-1, although unable to directly influence the growth of human glioma U-373 cells, induced Jurkat cells to synthesize and release factors that, in turn, inhibited the U-373 cell proliferation. Overall, these findings imply that Er-1 coupling to IL-2R and ERK immuno-enhances T-cell activity, and that this effect likely translates to an inhibition of glioma cell growth. -- Highlights: ► Euplotes pheromone Er-1 increases the growth of human Jurkat T-cells. ► Er-1 increases the T-cell production of specific cytokines. ► Er-1 activates interleukin-2 receptor and extracellular signal-regulated kinases. ► The immuno-enhancing effect of Er-1 on Jurkat cells translates to an inhibition of human glioma cell growth.

  11. The role of interleukin-1ß and interleukin-33 in atopic dermatitis

    Directory of Open Access Journals (Sweden)

    Rania M. Abdel Hay

    2013-01-01

    Full Text Available Introduction: Interleukin-1 super family is a group of cytokines that play a role in the regulation of immune and inflammatory responses. Interleukin-33 is a member of this family and is known to induce expression of the T helper2 cytokines that are important players in atopic dermatitis. Aim: To evaluate the expression of interleukins-1ß and 33 as T helper2 cytokines inducers in patients with atopic dermatitis. Materials andMethods: This study included 20 atopic patients and 20 apparently healthy individuals serving as controls. Skin biopsies from all participants will be examined for detection of interleukins-1ß and 33 by ELISA technique.Results: Both interleukins were statistically higher (P<0.001 in patients than in controls. A statistically significant (P=0.011 highest levels of interleukin-33 was detected in severe cases of atopics when compared to mild and moderate cases. A significant correlation (r=0.632, P=0.003 between both interleukins was detected in atopics.Conclusions: This is the first study to evaluate both interleukin-1ß and33 together in atopic patients. Both interleukins could play a role in the recruitment of lymphocytes during the inflammatory reaction in atopic dermatitis and could be targeted in the treatment of resistant cases.

  12. Phosphorylation of ERK in neurokinin 1 receptor-expressing neurons in laminae III and IV of the rat spinal dorsal horn following noxious stimulation

    Directory of Open Access Journals (Sweden)

    Watanabe Masahiko

    2007-02-01

    Full Text Available Abstract Background There is a population of large neurons with cell bodies in laminae III and IV of the spinal dorsal horn which express the neurokinin 1 receptor (NK1r and have dendrites that enter the superficial laminae. Although it has been shown that these are all projection neurons and that they are innervated by substance P-containing (nociceptive primary afferents, we know little about their responses to noxious stimuli. In this study we have looked for phosphorylation of extracellular signal-regulated kinases (ERKs in these neurons in response to different types of noxious stimulus applied to one hindlimb of anaesthetised rats. The stimuli were mechanical (repeated pinching, thermal (immersion in water at 52°C or chemical (injection of 2% formaldehyde. Results Five minutes after each type of stimulus we observed numerous cells with phosphorylated ERK (pERK in laminae I and IIo, together with scattered positive cells in deeper laminae. We found that virtually all of the lamina III/IV NK1r-immunoreactive neurons contained pERK after each of these stimuli and that in the great majority of cases there was internalisation of the NK1r on the dorsal dendrites of these cells. In addition, we also saw neurons in lamina III that were pERK-positive but lacked the NK1r, and these were particularly evident in animals that had had the pinch stimulus. Conclusion Our results demonstrate that lamina III/IV NK1r-immunoreactive neurons show receptor internalisation and ERK phosphorylation after mechanical, thermal or chemical noxious stimuli.

  13. PPARγ1 phosphorylation enhances proliferation and drug resistance in human fibrosarcoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Pang, Xiaojuan; Shu, Yuxin; Niu, Zhiyuan; Zheng, Wei; Wu, Haochen [State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing (China); Lu, Yan, E-mail: luyan@nju.edu.cn [State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing (China); Shen, Pingping, E-mail: ppshen@nju.edu.cn [State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing (China); Model Animal Research Center (MARC), Nanjing University, Nanjing (China)

    2014-03-10

    Post-translational regulation plays a critical role in the control of cell growth and proliferation. The phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ) is the most important post-translational modification. The function of PPARγ phosphorylation has been studied extensively in the past. However, the relationship between phosphorylated PPARγ1 and tumors remains unclear. Here we investigated the role of PPARγ1 phosphorylation in human fibrosarcoma HT1080 cell line. Using the nonphosphorylation (Ser84 to alanine, S84A) and phosphorylation (Ser84 to aspartic acid, S84D) mutant of PPARγ1, the results suggested that phosphorylation attenuated PPARγ1 transcriptional activity. Meanwhile, we demonstrated that phosphorylated PPARγ1 promoted HT1080 cell proliferation and this effect was dependent on the regulation of cell cycle arrest. The mRNA levels of cyclin-dependent kinase inhibitor (CKI) p21{sup Waf1/Cip1} and p27{sup Kip1} descended in PPARγ1{sup S84D} stable HT1080 cell, whereas the expression of p18{sup INK4C} was not changed. Moreover, compared to the PPARγ1{sup S84A}, PPARγ1{sup S84D} up-regulated the expression levels of cyclin D1 and cyclin A. Finally, PPARγ1 phosphorylation reduced sensitivity to agonist rosiglitazone and increased resistance to anticancer drug 5-fluorouracil (5-FU) in HT1080 cell. Our findings establish PPARγ1 phosphorylation as a critical event in human fibrosarcoma growth. These findings raise the possibility that chemical compounds that prevent the phosphorylation of PPARγ1 could act as anticancer drugs. - Highlights: • Phosphorylation attenuates PPARγ1 transcriptional activity. • Phosphorylated PPARγ1 promotes HT1080 cells proliferation. • PPARγ1 phosphorylation regulates cell cycle by mediating expression of cell cycle regulators. • PPARγ1 phosphorylation reduces sensitivity to agonist and anticancer drug. • Our findings establish PPARγ1 phosphorylation as a critical event in HT1080

  14. Interleukin-9 receptor α chain mRNA formation in CD8+ T cells producing anti-human immunodeficiency virus type 1 substance(s)

    International Nuclear Information System (INIS)

    Hossain, M.M.; Tsuchie, H.; Detorio, M.A.; Shirono, H.; Hara, C.; Nishimoto, A.; Saji, A.; Koga, J.; Takata, N.; Maniar, J.K.; Saple, D.G.; Taniguchi, K.; Kageyama, S.; Ichimura, H.; Kurimura, T.

    1998-01-01

    A search for gene(s) associated with anti-human immunodeficiency virus type 1 (HIV-l) activity of CD8 + T cells was attempted using molecular cloning and the relation between the anti-HIV activity of CD8 + T cells and the interleukin-9 receptor a chain (IL-9R-α) mRNA expression from the cDNA clones obtained was examined. The anti-HIV-l activity of CD8 + T cell culture supernatants was assessed by measuring the level of HIV-l replication in a CD4 + T cell line transfected with an infectious HIV-l DNA clone. IL-9R-a mRNA was assayed by reverse transcriptase-polymerase chain reaction (RT-PCR). Of 5 cases showing high level of anti-HIV-l activity (more than 80% suppression of HIV-l replication), the mRNA was detected in 4 cases. Of 10 cases showing low level of anti-HIV-l activity (less than 80% suppression of HIV-l replication), the mRNA was detected in one case. Soluble recombinant human IL-9 receptor (rhIL-9sR) did not suppress HIV-l replication at a concentration of 1 μg/ml. These data suggest that the IL-9R-a mRNA formation in CD8 + T cells may correlate with and play some role in the anti-HIV-l activity of CD8+ T cells from HIV-l-infected individuals. Key words: CD8+ T cells; anti-HIV-l activity; cytokines; interleukin-9 receptor (authors)

  15. H2O2 attenuates IGF-1R tyrosine phosphorylation and its survival signaling properties in neuronal cells via NR2B containing NMDA receptor.

    Science.gov (United States)

    Zeng, Zhiwen; Wang, Dejun; Gaur, Uma; Rifang, Liao; Wang, Haitao; Zheng, Wenhua

    2017-09-12

    Impairment of insulin-like growth factor I (IGF-I) signaling plays an important role in the development of neurodegeneration. In the present study, we investigated the effect of H 2 O 2 on the survival signaling of IGF-1 and its underlying mechanisms in human neuronal cells SH-SY5Y. Our results showed that IGF-1 promoted cell survival and stimulated phosphorylation of IGF-1R as well as its downstream targets like AKT and ERK1/2 in these cells. Meanwhile, these effects of IGF-1 were abolished by H 2 O 2 at 200μM concentration which did not cause any significant toxicity to cells itself in our experiments. Moreover, studies using various glutamate receptor subtype antagonists displayed that N-methyl-D -aspartate (NMDA) receptor antagonist dizocilpine maleate (MK-801) blocked the effects of H 2 O 2 , whereas other glutamate receptor subtype antagonists, such as non-NMDA receptor antagonist 6,7-dinitroquinoxaline-2,3-dione (DNQX), metabolic glutamate receptor antagonists LY341495 and CPCCOEt, had no effect. Further studies revealed that NR2B-containing NMDARs are responsible for these effects as its effects were blocked by pharmacological inhibitor Ro25-698 or specific siRNA for NR2B, but not NR2A. Finally, our data also showed that Ca 2+ influx contributes to the effects of H 2 O 2 . Similar results were obtained in primary cultured cortical neurons. Taken together, the results from the present study suggested that H 2 O 2 attenuated IGF-1R tyrosine phosphorylation and its survival signaling properties via NR2B containing NMDA receptors and Ca 2+ influx in SH-SY5Y cells. Therefore, NMDAR antagonists, especially NR2B-selective ones, combined with IGF-1 may serve as an alternative therapeutic agent for oxidative stress related neurodegenerative disease.

  16. Interleukin-1 (IL-1 system gene expression in granulosa cells: kinetics during terminal preovulatory follicle maturation in the mare

    Directory of Open Access Journals (Sweden)

    Gérard Nadine

    2003-05-01

    Full Text Available Abstract Background A growing body of evidences suggests that the ovary is a site of inflammatory reactions, and thus, ovarian cells could represent sources and targets of the interleukin-1 (IL-1 system. The purpose of this study was to examine the IL-1 system gene expressions in equine granulosa cells, and to study the IL-1β content in follicular fluid during the follicle maturation. For this purpose, granulosa cells and follicular fluids were collected from the largest follicle at the early dominance stage (diameter 24 ± 3 mm or during the preovulatory maturation phase, at T0 h, T6 h, T12 h, T24 h and T34 h after induction of ovulation. Cells were analysed by RT-PCR and follicular fluids were studied by gel electrophoresis and immunoblotting. Results We demonstrated that interleukin-1β (IL-1β, interleukin-1 receptor 2 (IL-1R2 and interleukin-1 receptor antagonist (IL-1RA genes are expressed in equine granulosa cells. We observed that the IL-1β and IL-1RA mRNA content changed in granulosa cells during the terminal follicular maturation whereas IL-1R2 mRNA did not vary. In follicular fluid, IL-1β content fluctuated few hours after induction of ovulation. Conclusions The expression of IL-1β gene in granulosa cells and the follicular fluid IL-1β content seem to be regulated by gonadotropins suggesting that IL-1β could be an intermediate paracrine factor involved in ovulation.

  17. PROLACTIN-INDUCED TYROSINE PHOSPHORYLATION, ACTIVATION AND RECEPTOR ASSOCIATION OF FOCAL ADHESION KINASE (FAK) IN MAMMARY EPITHELIAL CELLS

    Science.gov (United States)

    Prolactin-Induced Tyrosine Phosphorylation, Activation and ReceptorAssociation of Focal Adhesion Kinase (FAK) in Mammary Epithelial Cells. Suzanne E. Fenton1 and Lewis G. Sheffield2. 1U.S. Environmental ProtectionAgency, MD-72, Research Triangle Park, NC 27711, and

  18. Interleukin-34 Regulates Th1 and Th17 Cytokine Production by Activating Multiple Signaling Pathways through CSF-1R in Chicken Cell Lines

    Directory of Open Access Journals (Sweden)

    Anh Duc Truong

    2018-06-01

    Full Text Available Interleukin-34 (IL-34 is a newly recognized cytokine with functions similar to macrophage colony-stimulating factor 1. It is expressed in macrophages and fibroblasts, where it induces cytokine production; however, the mechanism of chicken IL-34 (chIL-34 signaling has not been identified to date. The aim of this study was to analyze the signal transduction pathways and specific biological functions associated with chIL-34 in chicken macrophage (HD11 and fibroblast (OU2 cell lines. We found that IL-34 is a functional ligand for the colony-stimulating factor receptor (CSF-1R in chicken cell lines. Treatment with chIL-34 increased the expression of Th1 and Th17 cytokines through phosphorylation of tyrosine and serine residues in Janus kinase (JAK 2, tyrosine kinase 2 (TYK2, signal transducer and activator of transcription (STAT 1, STAT3, and Src homology 2-containing tyrosine phosphatase 2 (SHP-2, which also led to phosphorylation of NF-κB1, p-mitogen-activated protein kinase kinase kinase 7 (TAK1, MyD88, suppressor of cytokine signaling 1 (SOCS1, and extracellular signal-regulated kinase 1 and 2 (ERK1/2. Taken together, these results suggest that chIL-34 functions by binding to CSF-1R and activating the JAK/STAT, nuclear factor κ B (NF-κB, and mitogen-activated protein kinase signaling pathways; these signaling events regulate cytokine expression and suggest roles for chIL-34 in innate and adaptive immunity.

  19. Five genetic markers in the interleukin 1 family in relation to inflammatory bowel disease

    NARCIS (Netherlands)

    Stokkers, P. C.; van Aken, B. E.; Basoski, N.; Reitsma, P. H.; Tytgat, G. N.; van Deventer, S. J.

    1998-01-01

    An imbalance between the proinflammatory cytokine interleukin 1 beta (IL-1 beta) and the anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) has been postulated as a pathogenic factor in inflammatory bowel disease (IBD). To study allelic frequencies of novel polymorphisms in the genes for

  20. Structure-function relationships for the interleukin 2 receptor system

    Directory of Open Access Journals (Sweden)

    Richard J. Robb

    1987-01-01

    Full Text Available Receptors for interleukin 2 (IL-2 esit in at least three forms which differ in their subunit compositio, their affinity for ligand and their ability to mediate a cellular reponse. Type I receptors occur following cellular acitivation and consist of the 55,000 m. w. glycoprotein Tac. These receptors bind IL-2 with a low affinity, do not internalize ligand and have not been definitively associated with any response. Type II receptors, on the other hand, conssit of one or more glycoproteins of 70,000 m. w. which have been termed "beta ([beta] chains." They bind IL-2 with an intermediate affinity and rapidly internalize the ligand. [Beta] proteins mediate many cellular IL-2-dependent reponses, including the short-term activation of natural killer cells and the induction of Tac protein expression. Type III receptors consist of a ternary complex of the Tac protein, the [beta] chain(s and IL-2. They are characterized by a paricularly high affinity for ligand association. Type III receptors also internalize ligand and mediate IL-2-dependent responses at low factor concentrations. The identification of two independent IL-2-binding molecules, Tac and [beta], thus provides the elusive molecular explanation for the differences in IL-2 receptor affinity and suggests the potential for selective therapeutic manipulation of IL-2 reponses.

  1. Human interleukin 1. beta. stimulates islet insulin release by a mechanism not dependent on changes in phospholipase C and protein kinase C activities or Ca sup 2+ handling

    Energy Technology Data Exchange (ETDEWEB)

    Welsh, N.; Nilsson, T.; Hallberg, A.; Arkhammar, P.; Berggren, P.-O.; Sandler, S.

    1989-01-01

    Isolated islets from adult rats or obese hyperglycemic (ob/ob) mice were incubated with human recombinant interleukin 1{beta} in order to study whether the acute effects of the cytokine on islet insulin release are associated with changes in islet phospholipase C activity, Ca{sup 2+} handling or protein phosphorylation. The cytokine stimulated insulin release both at low and high glucose concentrations during one hour incubations. In shortterm incubations (<1 min) interleukin 1{beta} did not affect the production of inositoltrisphosphate. Addition of interleukin 1{beta} affected neither the cytoplasmic free Ca{sup 2+} concentration at rest nor that observed subsequent to stimulation with a high concentration of glucose. Furthermore, the endogenous protein kinase C activity, as visualized by immunoprecipitation of a {sup 32}P-labelled substrate for this enzyme, was not altered by interleukin 1{beta}. Separation of {sup 32}P-labelled proteins by means of 2-dimensional gel electrophoresis failed to reveal any specific effects of the cytokine on the total protein phosphorylation activity. These results suggest that the stimulatory effects on insulin release exerted by interleukin 1{beta} are not caused by acute activation of phospholipase C and protein kinase C or by an alternation of islet Ca{sup 2+} handling of the B-cells. (author).

  2. Prenatal stress affects insulin-like growth factor-1 (IGF-1) level and IGF-1 receptor phosphorylation in the brain of adult rats.

    Science.gov (United States)

    Basta-Kaim, Agnieszka; Szczesny, Ewa; Glombik, Katarzyna; Stachowicz, Katarzyna; Slusarczyk, Joanna; Nalepa, Irena; Zelek-Molik, Agnieszka; Rafa-Zablocka, Katarzyna; Budziszewska, Boguslawa; Kubera, Marta; Leskiewicz, Monika; Lason, Wladyslaw

    2014-09-01

    It has been shown that stressful events occurring in early life have a powerful influence on the development of the central nervous system. Insulin-like growth factor-1 (IGF-1) promotes the growth, differentiation and survival of both neurons and glial cells and is thought to exert antidepressant-like activity. Thus, it is possible that disturbances in the function of the IGF-1 system may be responsible for disturbances observed over the course of depression. Prenatal stress was used as a valid model of depression. Adult male offspring of control and stressed rat dams were subjected to behavioural testing (forced swim test). The level of IGF-1 in the blood and the expression of IGF-1, IGF-1R, and IRS-1/2 in the hippocampus and frontal cortex using RT-PCR, ELISA and western blotting were measured. In addition the effect of intracerebroventricularly administered IGF-1 and/or the IGF-1R receptor antagonist JB1 in the forced swim test was studied. Prenatally stressed rats showed depressive like behaviour, including increased immobility time as well as decreased mobility and climbing. Intracerebroventricular administration of IGF-1 reversed these effects in stressed animals, whereas concomitant administration of the IGF-1R antagonist JB1 completely blocked the effects. Biochemical analysis of homogenates from the hippocampus and frontal cortex revealed decreases in IGF-1 level and IGF-1R phosphorylation along with disturbances in IRS-1 phosphorylation. These findings reveal that prenatal stress alters IGF-1 signalling, which may contribute to the behavioural changes observed in depression. Copyright © 2014 Elsevier B.V. and ECNP. All rights reserved.

  3. Self-renewal of human embryonic stem cells requires insulin-like growth factor-1 receptor and ERBB2 receptor signaling

    Science.gov (United States)

    Wang, Linlin; Schulz, Thomas C.; Sherrer, Eric S.; Dauphin, Derek S.; Shin, Soojung; Nelson, Angelique M.; Ware, Carol B.; Zhan, Mei; Song, Chao-Zhong; Chen, Xiaoji; Brimble, Sandii N.; McLean, Amanda; Galeano, Maria J.; Uhl, Elizabeth W.; D'Amour, Kevin A.; Chesnut, Jonathan D.; Rao, Mahendra S.

    2007-01-01

    Despite progress in developing defined conditions for human embryonic stem cell (hESC) cultures, little is known about the cell-surface receptors that are activated under conditions supportive of hESC self-renewal. A simultaneous interrogation of 42 receptor tyrosine kinases (RTKs) in hESCs following stimulation with mouse embryonic fibroblast (MEF) conditioned medium (CM) revealed rapid and prominent tyrosine phosphorylation of insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R); less prominent tyrosine phosphorylation of epidermal growth factor receptor (EGFR) family members, including ERBB2 and ERBB3; and trace phosphorylation of fibroblast growth factor receptors. Intense IGF1R and IR phosphorylation occurred in the absence of MEF conditioning (NCM) and was attributable to high concentrations of insulin in the proprietary KnockOut Serum Replacer (KSR). Inhibition of IGF1R using a blocking antibody or lentivirus-delivered shRNA reduced hESC self-renewal and promoted differentiation, while disruption of ERBB2 signaling with the selective inhibitor AG825 severely inhibited hESC proliferation and promoted apoptosis. A simple defined medium containing an IGF1 analog, heregulin-1β (a ligand for ERBB2/ERBB3), fibroblast growth factor-2 (FGF2), and activin A supported long-term growth of multiple hESC lines. These studies identify previously unappreciated RTKs that support hESC proliferation and self-renewal, and provide a rationally designed medium for the growth and maintenance of pluripotent hESCs. PMID:17761519

  4. Effects of interleukin-1 receptor antagonist (IL-1Ra) gene 86 bp VNTR polymorphism on recurrent pregnancy loss: a case-control study.

    Science.gov (United States)

    Hajizadeh, Yasamin Sayed; Emami, Elina; Nottagh, Marina; Amini, Zahra; Maroufi, Nazila Fathi; Azimian, Saba Haj; Isazadeh, Alireza

    2017-05-26

    Objective Recurrent pregnancy loss (RPL) is a heterogeneous disease which is defined as two or more consecutive fetal losses during early pregnancy. Interleukin-1 receptor antagonist (IL-1Ra) is a anti-inflammatory cytokine, which inhibits IL-1 activity by binding to its receptors. The aim of this study was to investigate the association between RPL and IL-1Ra intron 2 polymorphism (86 bp VNTR) in Iranian women. Materials and methods In this case control study, genetic polymorphism was studied in 140 RPL patients and 140 healthy women as controls. Genomic DNA was extracted from the blood samples and polymorphism analysis was performed using the polymerase chain reaction (PCR) method. Finally, the data obtained were analyzed by statistical software. Results We found an increased frequency of the IL-1Ra 1/1 genotype in the case group compared to the control group. Whereas, the frequency of IL-1Ra genotype 1/2 was higher in control group than in the case group. However, we did not observe an association between IL-1Ra 86 bp VNTR polymorphism in intron 2 and RPL patients (p > 0.05). Conclusion IL-1Ra VNTR polymorphism may not be a genetic factor for RPL. However, investigation of IL-1Ra polymorphism was recommended in other populations and patients with recurrent pregnancy loss.

  5. Characterization of phosphorylation sites in the cytoplasmic domain of the 300 kDa mannose-6-phosphate receptor

    DEFF Research Database (Denmark)

    Rosorius, O; Mieskes, G; Issinger, O G

    1993-01-01

    The human 300 kDa mannose-6-phosphate receptor (MPR 300) is phosphorylated in vivo at serine residues of its cytoplasmic domain. Two-dimensional separation can resolve tryptic phosphopeptides into four major species. To identify the kinases involved in MPR 300 phosphorylation and the phosphorylat......The human 300 kDa mannose-6-phosphate receptor (MPR 300) is phosphorylated in vivo at serine residues of its cytoplasmic domain. Two-dimensional separation can resolve tryptic phosphopeptides into four major species. To identify the kinases involved in MPR 300 phosphorylation...... and the phosphorylation sites the entire coding sequence of the cytoplasmic tail was expressed in Escherichia coli. The isolated cytoplasmic domain was used as a substrate for four purified serine/threonine kinases [casein kinase II (CK II), protein kinase A (PKA), protein kinase C and Ca2+/calmodulin kinase]. All...... kinases phosphorylate the cytoplasmic tail exclusively on serine residues. Inhibition studies using synthetic peptides, partial sequencing of isolated tryptic phosphopeptides and co-migration with tryptic phosphopeptides from MPR 300 labelled in vivo showed that (i) PKA phosphorylates the cytoplasmic MPR...

  6. Clinical features of Candidiasis in patients with inherited interleukin 12 receptor β1 deficiency.

    Science.gov (United States)

    Ouederni, Monia; Sanal, Ozden; Ikinciogullari, Aydan; Tezcan, Ilhan; Dogu, Figen; Sologuren, Ithaisa; Pedraza-Sánchez, Sigifredo; Keser, Melike; Tanir, Gonul; Nieuwhof, Chris; Colino, Elena; Kumararatne, Dinakantha; Levy, Jacov; Kutukculer, Necil; Aytekin, Caner; Herrera-Ramos, Estefanía; Bhatti, Micah; Karaca, Neslihan; Barbouche, Ridha; Broides, Arnon; Goudouris, Ekaterini; Franco, José Luis; Parvaneh, Nima; Reisli, Ismail; Strickler, Alexis; Shcherbina, Anna; Somer, Ayper; Segal, Anthony; Angel-Moreno, Alfonso; Lezana-Fernandez, José Luis; Bejaoui, Mohamed; Bobadilla-Del Valle, Miriam; Kachboura, Salem; Sentongo, Timothy; Ben-Mustapha, Imen; Bustamante, Jacinta; Picard, Capucine; Puel, Anne; Boisson-Dupuis, Stéphanie; Abel, Laurent; Casanova, Jean-Laurent; Rodríguez-Gallego, Carlos

    2014-01-01

    Interleukin 12Rβ1 (IL-12Rβ1)-deficient patients are prone to clinical disease caused by mycobacteria, Salmonella, and other intramacrophagic pathogens, probably because of impaired interleukin 12-dependent interferon γ production. About 25% of patients also display mucocutaneous candidiasis, probably owing to impaired interleukin 23-dependent interleukin 17 immunity. The clinical features and outcome of candidiasis in these patients have not been described before, to our knowledge. We report here the clinical signs of candidiasis in 35 patients with IL-12Rβ1 deficiency. Most (n = 71) of the 76 episodes of candidiasis were mucocutaneous. Isolated oropharyngeal candidiasis (OPC) was the most common presentation (59 episodes, 34 patients) and was recurrent or persistent in 26 patients. Esophageal candidiasis (n = 7) was associated with proven OPC in 2 episodes, and cutaneous candidiasis (n = 2) with OPC in 1 patient, whereas isolated vulvovaginal candidiasis (VVC; n = 3) was not. Five episodes of proven invasive candidiasis were documented in 4 patients; 1 of these episodes was community acquired in the absence of any other comorbid condition. The first episode of candidiasis occurred earlier in life (median age±standard deviation, 1.5 ± 7.87 years) than infections with environmental mycobacteria (4.29 ± 11.9 years), Mycobacterium tuberculosis (4 ± 3.12 years), or Salmonella species (4.58 ± 4.17 years) or other rare infections (3 ± 11.67 years). Candidiasis was the first documented infection in 19 of the 35 patients, despite the vaccination of 10 of these 19 patients with live bacille Calmette-Guérin. Patients who are deficient in IL-12Rβ1 may have candidiasis, usually mucocutaneous, which is frequently recurrent or persistent. Candidiasis may be the first clinical manifestation in these patients.

  7. Clinical Features of Candidiasis in Patients With Inherited Interleukin 12 Receptor β1 Deficiency

    Science.gov (United States)

    Ouederni, Monia; Sanal, Ozden; Ikincioğullari, Aydan; Tezcan, Ilhan; Dogu, Figen; Sologuren, Ithaisa; Pedraza-Sánchez, Sigifredo; Keser, Melike; Tanir, Gonul; Nieuwhof, Chris; Colino, Elena; Kumararatne, Dinakantha; Levy, Jacov; Kutukculer, Necil; Aytekin, Caner; Herrera-Ramos, Estefanía; Bhatti, Micah; Karaca, Neslihan; Barbouche, Ridha; Broides, Arnon; Goudouris, Ekaterini; Franco, José Luis; Parvaneh, Nima; Reisli, Ismail; Strickler, Alexis; Shcherbina, Anna; Somer, Ayper; Segal, Anthony; Angel-Moreno, Alfonso; Lezana-Fernandez, José Luis; Bejaoui, Mohamed; Bobadilla-Del Valle, Miriam; Kachboura, Salem; Sentongo, Timothy; Ben-Mustapha, Imen; Bustamante, Jacinta; Picard, Capucine; Puel, Anne; Boisson-Dupuis, Stéphanie; Abel, Laurent; Casanova, Jean-Laurent; Rodríguez-Gallego, Carlos

    2014-01-01

    Background. Interleukin 12Rβ1 (IL-12Rβ1)–deficient patients are prone to clinical disease caused by mycobacteria, Salmonella, and other intramacrophagic pathogens, probably because of impaired interleukin 12–dependent interferon γ production. About 25% of patients also display mucocutaneous candidiasis, probably owing to impaired interleukin 23–dependent interleukin 17 immunity. The clinical features and outcome of candidiasis in these patients have not been described before, to our knowledge. We report here the clinical signs of candidiasis in 35 patients with IL-12Rβ1 deficiency. Results. Most (n = 71) of the 76 episodes of candidiasis were mucocutaneous. Isolated oropharyngeal candidiasis (OPC) was the most common presentation (59 episodes, 34 patients) and was recurrent or persistent in 26 patients. Esophageal candidiasis (n = 7) was associated with proven OPC in 2 episodes, and cutaneous candidiasis (n = 2) with OPC in 1 patient, whereas isolated vulvovaginal candidiasis (VVC; n = 3) was not. Five episodes of proven invasive candidiasis were documented in 4 patients; 1 of these episodes was community acquired in the absence of any other comorbid condition. The first episode of candidiasis occurred earlier in life (median age±standard deviation, 1.5 ± 7.87 years) than infections with environmental mycobacteria (4.29 ± 11.9 years), Mycobacterium tuberculosis (4 ± 3.12 years), or Salmonella species (4.58 ± 4.17 years) or other rare infections (3 ± 11.67 years). Candidiasis was the first documented infection in 19 of the 35 patients, despite the vaccination of 10 of these 19 patients with live bacille Calmette-Guérin. Conclusions. Patients who are deficient in IL-12Rβ1 may have candidiasis, usually mucocutaneous, which is frequently recurrent or persistent. Candidiasis may be the first clinical manifestation in these patients. PMID:24186907

  8. Interleukin-6 triggers human cerebral endothelial cells proliferation and migration: The role for KDR and MMP-9

    International Nuclear Information System (INIS)

    Yao, Jianhua S.; Zhai Wenwu; Young, William L.; Yang Guoyuan

    2006-01-01

    Interleukin-6 (IL-6) is involved in angiogenesis. However, the underlying mechanisms are unknown. Using human cerebral endothelial cell (HCEC), we report for First time that IL-6 triggers HCEC proliferation and migration in a dose-dependent manner, specifically associated with enhancement of VEGF expression, up-regulated and phosphorylated VEGF receptor-2 (KDR), and stimulated MMP-9 secretion. We investigated the signal pathway of IL-6/IL-6R responsible for KDR's regulation. Pharmacological inhibitor of PI3K failed to inhibit IL-6-mediated VEGF overexpression, while blocking ERK1/2 with PD98059 could abolish IL-6-induced KDR overexpression. Further, neutralizing endogenous VEGF attenuated KDR expression and phosphorylation, suggesting that IL-6-induced KDR activation is independent of VEGF stimulation. MMP-9 inhibitor GM6001 significantly decreases HCEC proliferation and migration (p < 0.05), indicating the crucial function of MMP-9 in promoting angiogenic changes in HCECs. We conclude that IL-6 triggers VEGF-induced angiogenic activity through increasing VEGF release, up-regulates KDR expression and phosphorylation through activating ERK1/2 signaling, and stimulates MMP-9 overexpression

  9. Interleukin-6 stimulates Akt and p38 MAPK phosphorylation and fibroblast migration in non-diabetic but not diabetic mice.

    Directory of Open Access Journals (Sweden)

    Tsubame Nishikai-Yan Shen

    Full Text Available Persistent inflammatory environment and abnormal macrophage activation are characteristics of chronic diabetic wounds. Here, we attempted to characterize the differences in macrophage activation and temporal variations in cytokine expression in diabetic and non-diabetic wounds, with a focus on interleukin (IL-6 mRNA expression and the p38 MAPK and PI3K/Akt signaling pathways. Cutaneous wound closure, CD68- and arginase-1 (Arg-1-expressing macrophages, and cytokine mRNA expression were examined in non-diabetic and streptozotocin-induced type 1 diabetic mice at different time points after injury. The effect of IL-6 on p38 MAPK and Akt phosphorylation was investigated, and an in vitro scratch assay was performed to determine the role of IL-6 in primary skin fibroblast migration. Before injury, mRNA expression levels of the inflammatory markers iNOS, IL-6, and TNF-α were higher in diabetic mice; however, IL-6 expression was significantly lower 6 h post injury in diabetic wounds than that in non-diabetic wounds. Non-diabetic wounds exhibited increased p38 MAPK and Akt phosphorylation; however, no such increase was found in diabetic wounds. In fibroblasts from non-diabetic mice, IL-6 increased the phosphorylation of p38 MAPK and levels of its downstream factor CREB, and also significantly increased Akt phosphorylation and levels of its upstream factor P13K. These effects of IL-6 were not detected in fibroblasts derived from the diabetic mice. In scratch assays, IL-6 stimulated the migration of primary cultured skin fibroblasts from the non-diabetic mice, and the inhibition of p38 MAPK was found to markedly suppress IL-6-stimulated fibroblast migration. These findings underscore the critical differences between diabetic and non-diabetic wounds in terms of macrophage activation, cytokine mRNA expression profile, and involvement of the IL-6-stimulated p38 MAPK-Akt signaling pathway. Aberrant macrophage activation and abnormalities in the cytokine m

  10. The mechanisms behind decreased internalization of angiotensin II type 1 receptor.

    Science.gov (United States)

    Bian, Jingwei; Zhang, Suli; Yi, Ming; Yue, Mingming; Liu, Huirong

    2018-04-01

    The internalization of angiotensin II type 1 receptor (AT 1 R) plays an important role in maintaining cardiovascular homeostasis. Decreased receptor internalization is closely related to cardiovascular diseases induced by the abnormal activation of AT 1 R, such as hypertension. However, the mechanism behind reduced AT 1 R internalization is not fully understood. This review focuses on four parts of the receptor internalization process (the combination of agonists and receptors, receptor phosphorylation, endocytosis, and recycling) and summarizes the possible mechanisms by which AT 1 R internalization is reduced based on these four parts of the process. (1) The agonist has a large molecular weight or a stronger ability to hydrolyze phosphatidylinositol 4,5-bisphosphate (PtdIns (4,5) P 2 ), which can increase the consumption of PtdIns (4,5) P 2 . (2) AT 1 R phosphorylation is weakened because of an abnormal function of phosphorylated kinase or changes in phospho-barcoding and GPCR-β-arrestin complex conformation. (3) The abnormal formation of vesicles or AT 1 R heterodimers with fewer endocytic receptors results in less AT 1 R endocytosis. (4) The enhanced activity and upregulated expression of small GTP-binding protein 4 (Rab4) and 11 (Rab11), which regulate receptor recycling, and phosphatidylinositol 3-kinase increase AT 1 R recycling. In addition, lower expression of AT 1 R-associated protein (ATRAP) or higher expression of AT 1 R-associated protein 1 (ARAP1) can reduce receptor internalization. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Association of of IL-1 receptor antagonist (IL-1RN) and interleukin-1β genes (IL-1β) polymorphisms with recurrent pregnancy loss in Iranian Azeri women.

    Science.gov (United States)

    Ali Rahmani, Seyyed; Paknejad, Zeynab; Mohammadkhanlou, Masoumeh; Daneshparvar, Marina

    2017-12-27

    Objective One of the most important problems in human reproduction is recurrent pregnancy loss (RPL). RPL is defined as three or more consecutive abortions in the first trimester of pregnancy. The association between the polymorphisms in the immunological factors and RPL was investigated. The aim of our study was to determine the association of interleukin receptor antagonist (IL-IRN) and interleukin-1β (IL-1β) polymorphisms with RPL in Iranian Azeri women. Materials and methods The study participants consisted of 100 women with RPL of Iranian Azeri origin. The control group comprised 100 age- and ethnically-matched healthy women of the same reproductive age. Genomic DNA was extracted from the whole blood and genotype determinations were performed using polymerase chain reaction (PCR) amplification followed by restriction fragment length polymorphism (RFLP) analysis. Results Our results showed no significant relationship between IL-1RN polymorphism and RPL. The homozygous state in -857 C/T variant was seen to be higher in RPL patients than in control subjects. Also frequency of wild type genotype was lower in RPL patients than in controls. However, this associations was not significant. Conclusion This study suggested that -511 C/T (rs16944) and -31 C/T (rs1143627) polymorphisms in IL-1β gene may not be involved in RPL in Iranian Azeri women. Also the promoter polymorphism of the IL-1RN gene may not play a role in the susceptibility to RPL.

  12. A Role for Estrogen Receptor Phosphorylation in the Resistance to Tamoxifen

    International Nuclear Information System (INIS)

    De Leeuw, R.; Neefjes, J.; Michalides, R.

    2011-01-01

    About two thirds of all human breast cancer cases are estrogen receptor positive. The drug of first choice for these patients is tamoxifen. However, about half of the recurrences after removal of the primary tumor are or become resistant to this drug. While many mechanisms have been identified for tamoxifen resistance in the lab, at present only a few have been translated to the clinic. This paper highlights the role in tamoxifen resistance of phosphorylation by different kinases on different sites of the estrogen receptor. We will discuss the molecular pathways and kinases that are involved in phosphorylation of ERa and how these affect tamoxifen resistance. Finally, we will elaborate on the clinical translation of these observations and the possibility to predict tamoxifen responses in patient tumor samples before treatment onset. The findings made originally on the bench may translate into a better and personalized treatment of breast cancer patients using an old and safe anticancer drug: tamoxifen

  13. Interleukin-1 antagonism moderates the inflammatory state associated with Type 1 diabetes during clinical trials conducted at disease onset

    DEFF Research Database (Denmark)

    Cabrera, Susanne M; Wang, Xujing; Chen, Yi-Guang

    2016-01-01

    It was hypothesized that IL-1 antagonism would preserve β-cell function in new onset Type 1 diabetes (T1D). However, the Anti-Interleukin-1 in Diabetes Action (AIDA) and TrialNet Canakinumab (TN-14) trials failed to show efficacy of IL-1 receptor antagonist (IL-1Ra) or canakinumab, as measured...

  14. Phosphorylation of Threonine 794 on Tie1 by Rac1/PAK1 Reveals a Novel Angiogenesis Regulatory Pathway.

    Directory of Open Access Journals (Sweden)

    Jessica L Reinardy

    Full Text Available The endothelial receptor tyrosine kinase (RTK Tie1 was discovered over 20 years ago, yet its precise function and mode of action remain enigmatic. To shed light on Tie1's role in endothelial cell biology, we investigated a potential threonine phosphorylation site within the juxtamembrane domain of Tie1. Expression of a non-phosphorylatable mutant of this site (T794A in zebrafish (Danio rerio significantly disrupted vascular development, resulting in fish with stunted and poorly branched intersomitic vessels. Similarly, T794A-expressing human umbilical vein endothelial cells formed significantly shorter tubes with fewer branches in three-dimensional Matrigel cultures. However, mutation of T794 did not alter Tie1 or Tie2 tyrosine phosphorylation or downstream signaling in any detectable way, suggesting that T794 phosphorylation may regulate a Tie1 function independent of its RTK properties. Although T794 is within a consensus Akt phosphorylation site, we were unable to identify a physiological activator of Akt that could induce T794 phosphorylation, suggesting that Akt is not the physiological Tie1-T794 kinase. However, the small GTPase Ras-related C3 botulinum toxin substrate 1 (Rac1, which is required for angiogenesis and capillary morphogenesis, was found to associate with phospho-T794 but not the non-phosphorylatable T794A mutant. Pharmacological activation of Rac1 induced downstream activation of p21-activated kinase (PAK1 and T794 phosphorylation in vitro, and inhibition of PAK1 abrogated T794 phosphorylation. Our results provide the first demonstration of a signaling pathway mediated by Tie1 in endothelial cells, and they suggest that a novel feedback loop involving Rac1/PAK1 mediated phosphorylation of Tie1 on T794 is required for proper angiogenesis.

  15. Intense resistance exercise induces early and transient increases in ryanodine receptor 1 phosphorylation in human skeletal muscle.

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    Sebastian Gehlert

    Full Text Available BACKGROUND: While ryanodine receptor 1 (RyR1 critically contributes to skeletal muscle contraction abilities by mediating Ca²⁺ion oscillation between sarcoplasmatic and myofibrillar compartments, AMP-activated protein kinase (AMPK senses contraction-induced energetic stress by phosphorylation at Thr¹⁷². Phosphorylation of RyR1 at serine²⁸⁴³ (pRyR1Ser²⁸⁴³ results in leaky RyR1 channels and impaired Ca²⁺homeostasis. Because acute resistance exercise exerts decreased contraction performance in skeletal muscle, preceded by high rates of Ca²⁺-oscillation and energetic stress, intense myofiber contractions may induce increased RyR1 and AMPK phosphorylation. However, no data are available regarding the time-course and magnitude of early RyR1 and AMPK phosphorylation in human myofibers in response to acute resistance exercise. PURPOSE: Determine the effects and early time-course of resistance exercise on pRyR1Ser²⁸⁴³ and pAMPKThr¹⁷² in type I and II myofibers. METHODS: 7 male subjects (age 23±2 years, height: 185±7 cm, weight: 82±5 kg performed 3 sets of 8 repetitions of maximum eccentric knee extensions. Muscle biopsies were taken at rest, 15, 30 and 60 min post exercise. pRyR1Ser²⁸⁴³ and pAMPKThr¹⁷² levels were determined by western blot and semi-quantitative immunohistochemistry techniques. RESULTS: While total RyR1 and total AMPK levels remained unchanged, RyR1 was significantly more abundant in type II than type I myofibers. pRyR1Ser²⁸⁴³ increased 15 min and peaked 30 min (p<0.01 post exercise in both myofiber types. Type I fibers showed relatively higher increases in pRyR1Ser²⁸⁴³ levels than type II myofibers and remained elevated up to 60 min post resistance exercise (p<0.05. pAMPKThr¹⁷² also increased 15 to 30 min post exercise (p<0.01 in type I and II myofibers and in whole skeletal muscle. CONCLUSION: Resistance exercise induces acutely increased pRyR1Ser²⁸⁴³ and

  16. Duration and severity of symptoms and levels of plasma interleukin-1 receptor antagonist, soluble tumor necrosis factor receptor, and adhesion molecules in patients with common cold treated with zinc acetate.

    Science.gov (United States)

    Prasad, Ananda S; Beck, Frances W J; Bao, Bin; Snell, Diane; Fitzgerald, James T

    2008-03-15

    Zinc lozenges have been used for treatment of the common cold; however, the results remain controversial. Fifty ambulatory volunteers were recruited within 24 h of developing symptoms of the common cold for a randomized, double-blind, placebo-controlled trial of zinc. Participants took 1 lozenge containing 13.3 mg of zinc (as zinc acetate) or placebo every 2-3 h while awake. The subjective scores for common cold symptoms were recorded daily. Plasma zinc, soluble interleukin (IL)-1 receptor antagonist (sIL-1ra), soluble tumor necrosis factor receptor 1, soluble vascular endothelial cell adhesion molecule, and soluble intercellular adhesion molecule (sICAM)-1 were assayed on days 1 and 5. Compared with the placebo group, the zinc group had a shorter mean overall duration of cold (4.0 vs. 7.1 days; P cold symptoms. We related the improvement in cold symptoms to the antioxidant and anti-inflammatory properties of zinc.

  17. Selective delivery of interleukine-1 receptor antagonist to inflamed joint by albumin fusion

    Directory of Open Access Journals (Sweden)

    Liu Mengyuan

    2012-09-01

    Full Text Available Abstract Background Interleukin-1 receptor antagonist, a cytokine that is highly therapeutic to rheumatoid arthritis and several other inflammatory diseases, exhibits rapid blood clearance and poor retention time on the target in clinical application due to its small size and lack of specificity to target tissue. Albumin has been widely employed as macromolecular carrier for drug delivery purpose to extend the plasma half-life of therapeutic molecules and has been shown to selectively accumulate and to be metabolized in the inflamed joints of patients with rheumatoid arthritis. This suggests that genetic fusion of IL-1ra to albumin can probably overcome the drawbacks of in vivo application of IL-1ra. Result A recombinant protein, engineered by fusing human serum albumin (HSA to the carboxyl terminal of IL-1ra, was produced in Pichia pastoris and purified to homogeneity. The fusion protein retained the antagonist activity of IL-1ra and had a plasma half-life of approximately 30-fold more than that of IL-1ra in healthy mice. In vivo bio-distribution studies demonstrated that the fusion protein selectively accumulated in arthritic paws for a long period of time in mice with collagen-induced arthritis, showing low uptake rates in normal organs such as liver, kidney, spleen and lung in contrast to IL-1ra alone. Moreover, this fusion protein was able to significantly improve the therapeutic efficacy of IL-1ra in collagen-induced arthritis mouse model. Conclusions The fusion protein described here, able to selectively deliver IL-1ra to inflamed tissue, could yield important contributions for the therapy of rheumatoid arthritis and other inflammatory diseases.

  18. CysLT1 receptor-induced human airway smooth muscle cells proliferation requires ROS generation, EGF receptor transactivation and ERK1/2 phosphorylation

    Directory of Open Access Journals (Sweden)

    Capra Valérie

    2006-03-01

    Full Text Available Abstract Background Cysteine-containing leukotrienes (cysteinyl-LTs are pivotal inflammatory mediators that play important roles in the pathophysiology of asthma, allergic rhinitis, and other inflammatory conditions. In particular, cysteinyl-LTs exert a variety of effects with relevance to the aetiology of asthma such as smooth muscle contraction, eosinophil recruitment, increased microvascular permeability, enhanced mucus secretion and decreased mucus transport and, finally, airway smooth muscle cells (ASMC proliferation. We used human ASMC (HASMC to identify the signal transduction pathway(s of the leukotriene D4 (LTD4-induced DNA synthesis. Methods Proliferation of primary HASMC was measured by [3H]thymidine incorporation. Phosphorylation of EGF receptor (EGF-R and ERK1/2 was assessed with a polyclonal anti-EGF-R or anti-phosphoERKl/2 monoclonal antibody. A Ras pull-down assay kit was used to evaluate Ras activation. The production of reactive oxygen species (ROS was estimated by measuring dichlorodihydrofluorescein (DCF oxidation. Results We demonstrate that in HASMC LTD4-stimulated thymidine incorporation and potentiation of EGF-induced mitogenic signaling mostly depends upon EGF-R transactivation through the stimulation of CysLT1-R. Accordingly, we found that LTD4 stimulation was able to trigger the increase of Ras-GTP and, in turn, to activate ERK1/2. We show here that EGF-R transactivation was sensitive to pertussis toxin (PTX and phosphoinositide 3-kinase (PI3K inhibitors and that it occurred independently from Src activity, despite the observation of a strong impairment of LTD4-induced DNA synthesis following Src inhibition. More interestingly, CysLT1-R stimulation increased the production of ROS and N-acetylcysteine (NAC abolished LTD4-induced EGF-R phosphorylation and thymidine incorporation. Conclusion Collectively, our data demonstrate that in HASMC LTD4 stimulation of a Gi/o coupled CysLT1-R triggers the transactivation of the EGF

  19. Recruitment of SHP-1 protein tyrosine phosphatase and signalling by a chimeric T-cell receptor-killer inhibitory receptor

    DEFF Research Database (Denmark)

    Christensen, M D; Geisler, C

    2000-01-01

    Receptors expressing the immunoreceptor tyrosine-based inhibitory motif (ITIM) in their cytoplasmic tail play an important role in the negative regulation of natural killer and B-cell activation. A subpopulation of T cells expresses the ITIM containing killer cell inhibitory receptor (KIR), which...... recognize MHC class I molecules. Following coligation of KIR with an activating receptor, the tyrosine in the ITIM is phosphorylated and the cytoplasmic protein tyrosine phosphatase SHP-1 is recruited to the ITIM via its SH2 domains. It is still not clear how SHP-1 affects T-cell receptor (TCR) signalling...... regarding total protein tyrosine phosphorylation, TCR down-regulation, mobilization of intracellular free calcium, or induction of the activation markers CD69 and CD25....

  20. Heterologous activation of protein kinase C stimulates phosphorylation of delta-opioid receptor at serine 344, resulting in beta-arrestin- and clathrin-mediated receptor internalization

    DEFF Research Database (Denmark)

    Xiang, B; Yu, G H; Guo, J

    2001-01-01

    The purpose of the current study is to investigate the effect of opioid-independent, heterologous activation of protein kinase C (PKC) on the responsiveness of opioid receptor and the underlying molecular mechanisms. Our result showed that removing the C terminus of delta opioid receptor (DOR......) containing six Ser/Thr residues abolished both DPDPE- and phorbol 12-myristate 13-acetate (PMA)-induced DOR phosphorylation. The phosphorylation levels of DOR mutants T352A, T353A, and T358A/T361A/S363S were comparable to that of the wild-type DOR, whereas S344G substitution blocked PMA-induced receptor......, and ionomycin resulted in DOR internalization that required phosphorylation of Ser-344. Expression of dominant negative beta-arrestin and hypertonic sucrose treatment blocked PMA-induced DOR internalization, suggesting that PKC mediates DOR internalization via a beta-arrestin- and clathrin-dependent mechanism...

  1. IRS-1 serine phosphorylation and insulin resistance in skeletal muscle from pancreas tranplant recipient

    DEFF Research Database (Denmark)

    Bouzakri, K; Karlsson, HRK; Vestergaard, Henrik

    2006-01-01

    Insulin-dependent diabetic recipients of successful pancreas allografts achieve self-regulatory insulin secretion and discontinue exogenous insulin therapy; however, chronic hyperinsulinemia and impaired insulin sensitivity generally develop. To determine whether insulin resistance is accompanied....... In conclusion, peripheral insulin resistance in pancreas-kidney transplant recipients may arise from a negative feedback regulation of the canonical insulin-signaling cascade from excessive serine phosphorylation of IRS-1, possibly as a consequence of immunosuppressive therapy and hyperinsulinemia....... insulin receptor substrate (IRS)-1 Ser (312) and Ser (616) phosphorylation, IRS-1-associated phosphatidylinositol 3-kinase activity, and extracellular signal-regulated kinase (ERK)-1/2 phosphorylation were elevated in pancreas-kidney transplant recipients, coincident with fasting hyperinsulinemia. Basal...

  2. Interleukin-1 Receptor in Seizure Susceptibility after Traumatic Injury to the Pediatric Brain.

    Science.gov (United States)

    Semple, Bridgette D; O'Brien, Terence J; Gimlin, Kayleen; Wright, David K; Kim, Shi Eun; Casillas-Espinosa, Pablo M; Webster, Kyria M; Petrou, Steven; Noble-Haeusslein, Linda J

    2017-08-16

    Epilepsy after pediatric traumatic brain injury (TBI) is associated with poor quality of life. This study aimed to characterize post-traumatic epilepsy in a mouse model of pediatric brain injury, and to evaluate the role of interleukin-1 (IL-1) signaling as a target for pharmacological intervention. Male mice received a controlled cortical impact or sham surgery at postnatal day 21, approximating a toddler-aged child. Mice were treated acutely with an IL-1 receptor antagonist (IL-1Ra; 100 mg/kg, s.c.) or vehicle. Spontaneous and evoked seizures were evaluated from video-EEG recordings. Behavioral assays tested for functional outcomes, postmortem analyses assessed neuropathology, and brain atrophy was detected by ex vivo magnetic resonance imaging. At 2 weeks and 3 months post-injury, TBI mice showed an elevated seizure response to the convulsant pentylenetetrazol compared with sham mice, associated with abnormal hippocampal mossy fiber sprouting. A robust increase in IL-1β and IL-1 receptor were detected after TBI. IL-1Ra treatment reduced seizure susceptibility 2 weeks after TBI compared with vehicle, and a reduction in hippocampal astrogliosis. In a chronic study, IL-1Ra-TBI mice showed improved spatial memory at 4 months post-injury. At 5 months, most TBI mice exhibited spontaneous seizures during a 7 d video-EEG recording period. At 6 months, IL-1Ra-TBI mice had fewer evoked seizures compared with vehicle controls, coinciding with greater preservation of cortical tissue. Findings demonstrate this model's utility to delineate mechanisms underlying epileptogenesis after pediatric brain injury, and provide evidence of IL-1 signaling as a mediator of post-traumatic astrogliosis and seizure susceptibility. SIGNIFICANCE STATEMENT Epilepsy is a common cause of morbidity after traumatic brain injury in early childhood. However, a limited understanding of how epilepsy develops, particularly in the immature brain, likely contributes to the lack of efficacious treatments

  3. The insulin and IGF1 receptor kinase domains are functional dimers in the activated state

    Science.gov (United States)

    Cabail, M. Zulema; Li, Shiqing; Lemmon, Eric; Bowen, Mark E.; Hubbard, Stevan R.; Miller, W. Todd

    2015-03-01

    The insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1R) are highly related receptor tyrosine kinases with a disulfide-linked homodimeric architecture. Ligand binding to the receptor ectodomain triggers tyrosine autophosphorylation of the cytoplasmic domains, which stimulates catalytic activity and creates recruitment sites for downstream signalling proteins. Whether the two phosphorylated tyrosine kinase domains within the receptor dimer function independently or cooperatively to phosphorylate protein substrates is not known. Here we provide crystallographic, biophysical and biochemical evidence demonstrating that the phosphorylated kinase domains of IR and IGF1R form a specific dimeric arrangement involving an exchange of the juxtamembrane region proximal to the kinase domain. In this dimer, the active position of α-helix C in the kinase N lobe is stabilized, which promotes downstream substrate phosphorylation. These studies afford a novel strategy for the design of small-molecule IR agonists as potential therapeutic agents for type 2 diabetes.

  4. Contribution of interleukin-1 to activation of coagulation and fibrinolysis, neutrophil degranulation, and the release of secretory-type phospholipase A2 in sepsis: studies in nonhuman primates after interleukin-1 alpha administration and during lethal bacteremia

    NARCIS (Netherlands)

    Jansen, P. M.; Boermeester, M. A.; Fischer, E.; de Jong, I. W.; van der Poll, T.; Moldawer, L. L.; Hack, C. E.; Lowry, S. F.

    1995-01-01

    Although studies with interleukin-1 receptor antagonist (IL-1ra) in animal models have shown that IL-1 contributes to mortality in sepsis, the mechanisms whereby IL-1 mediates lethal effects are not well established. A possible mechanism is that IL-1 enhances the activation and release of other

  5. Ganoderma lucidum Polysaccharides Reduce Lipopolysaccharide-Induced Interleukin-1β Expression in Cultured Smooth Muscle Cells and in Thoracic Aortas in Mice

    Directory of Open Access Journals (Sweden)

    Chan-Jung Liang

    2014-01-01

    Full Text Available The expression of inflammatory cytokines on vascular walls is a critical event in vascular diseases and inflammation. The aim of the present study was to examine the effects of an extract of Ganoderma lucidum (Reishi polysaccharides (EORPs, which is effective against immunological disorders, on interleukin- (IL- 1β expression by human aortic smooth muscle cells (HASMCs and the underlying mechanism. The lipopolysaccharide- (LPS- induced IL-1β expression was significantly reduced when HASMCs were pretreated with EORP by Western blot and immunofluorescent staining. Pretreatment with 10 μg/mL EORP decreased LPS-induced ERK, p38, JNK, and Akt phosphorylation. But the increase in IL-1β expression with LPS treatment was only inhibited by pretreatment with the ERK1/2 inhibitor, while the JNK and p38 inhibitors had no effect. In addition, EORP reduced the phosphorylation and nuclear translocation of nuclear factor- (NF- κB p65 in LPS-treated HASMCs. Furthermore, in vivo, IL-1β expression was strongly expressed in thoracic aortas in LPS-treated mice. Oral administration of EORP decreased IL-1β expression. The level of IL-1β expression in LPS-treated or in LPS/EORP-treated group was very low and was similar to that of the saline-treated group in toll-like receptor 4-deficient (TLR4−/− mice. These findings suggest that EORP has the anti-inflammatory property and could prove useful in the prevention of vascular diseases and inflammatory responses.

  6. Decreased concentrations of soluble interleukin-1 receptor accessory protein levels in the peritoneal fluid of women with endometriosis.

    Science.gov (United States)

    Michaud, Nadège; Al-Akoum, Mahéra; Gagnon, Geneviève; Girard, Karine; Blanchet, Pierre; Rousseau, Julie Anne; Akoum, Ali

    2011-12-01

    Interleukin 1 (IL1) may play an important role in endometriosis-associated pelvic inflammation, and natural specific inhibitors, including soluble IL1 receptor accessory protein (sIL1RAcP) and soluble IL1 receptor type 2 (sIL1R2), are critical for counterbalancing the pleiotropic effects of IL1. The objective of this study was to evaluate the levels of sIL1RAcP, together with those of sIL1R2 and IL1β, in the peritoneal fluid of women with and without endometriosis. Peritoneal fluid samples were obtained at laparoscopy and assessed by ELISA. sIL1RAcP concentrations were reduced in endometriosis stages I-II and III-IV. sIL1R2 concentrations were decreased, and those of IL1β were significantly increased in endometriosis stages I-II. sIL1RAcP and sIL1R2 concentrations were significantly decreased in the secretory phase of the menstrual cycle, and IL1β concentrations were elevated in the proliferative and the secretory phases. sIL1RAcP and sIL1R2 concentrations were reduced in women with endometriosis who were infertile, fertile, suffering from pelvic pain or pain-free. However, IL1β concentrations were significantly reduced in women with endometriosis who were infertile or had pelvic pain. These changes may exacerbate the local peritoneal inflammatory reaction observed in women with endometriosis and contribute to endometriosis pathophysiology and the major symptoms of this disease. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  7. AZD5363 inhibits inflammatory synergy between interleukin-17 and insulin/insulin-like growth factor 1

    Directory of Open Access Journals (Sweden)

    Chong eChen

    2014-12-01

    Full Text Available In the United States, one third of population is affected by obesity and almost 29 million people are suffering from type 2 diabetes. Obese people have elevated serum levels of insulin, insulin-like growth factor 1 (IGF1 and interleukin-17 (IL-17. Insulin and IGF1 are known to enhance IL-17-induced expression of inflammatory cytokines and chemokines, which may contribute to the chronic inflammatory status observed in obese people. We have previously demonstrated that insulin/IGF1 signaling pathway crosstalks with IL-17-activated nuclear factor-kappa B (NF-κB pathway through inhibiting glycogen synthase kinase 3β (GSK3β activity. However, it is unclear whether GSK3α also plays a role and whether this crosstalk can be manipulated by AZD5363, a novel pan-Akt inhibitor that has been shown to increase GSK3 activity through reducing phosphorylation of GSK3α and GSK3β. In this study, we investigated IL-17-induced expression of C-X-C motif ligand 1 (Cxcl1, C-C motif ligand 20 (Ccl20 and interleukin-6 (Il-6 in wild-type, GSK3α-/-, and GSK3β-/- mouse embryonic fibroblast (MEF cells as well as in mouse prostate tissues by real-time quantitative PCR. We examined the proteins involved in the signaling pathways by Western blot analysis. We found that insulin and IGF1 enhanced IL-17- induced expression of Cxcl1, Ccl20 and Il-6, which was associated with increased phosphorylation of GSK3α and GSK3β in the presence of insulin and IGF1. AZD5363 inhibited the synergy between IL-17 and insulin/IGF1 through reducing phosphorylation of GSK3α and GSK3β by inhibiting Akt function. These findings imply that the cooperative crosstalk of IL-17 and insulin/IGF1 in initiating inflammatory responses may be alleviated by AZD5363.

  8. Acute ethanol intake induces superoxide anion generation and mitogen-activated protein kinase phosphorylation in rat aorta: A role for angiotensin type 1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Yogi, Alvaro; Callera, Glaucia E. [Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario (Canada); Mecawi, André S. [Department of Physiology, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP (Brazil); Batalhão, Marcelo E.; Carnio, Evelin C. [Department of General and Specialized Nursing, College of Nursing of Ribeirão Preto, USP, São Paulo (Brazil); Antunes-Rodrigues, José [Department of Physiology, Faculty of Medicine of Ribeirão Preto, University of São Paulo (USP), Ribeirão Preto, SP (Brazil); Queiroz, Regina H. [Department of Clinical, Toxicological and Food Science Analysis, Faculty of Pharmaceutical Sciences, USP, São Paulo (Brazil); Touyz, Rhian M. [Kidney Research Centre, Ottawa Hospital Research Institute, University of Ottawa, Ontario (Canada); Tirapelli, Carlos R., E-mail: crtirapelli@eerp.usp.br [Department of Psychiatric Nursing and Human Sciences, Laboratory of Pharmacology, College of Nursing of Ribeirão Preto, USP, Ribeirão Preto, SP (Brazil)

    2012-11-01

    Ethanol intake is associated with increase in blood pressure, through unknown mechanisms. We hypothesized that acute ethanol intake enhances vascular oxidative stress and induces vascular dysfunction through renin–angiotensin system (RAS) activation. Ethanol (1 g/kg; p.o. gavage) effects were assessed within 30 min in male Wistar rats. The transient decrease in blood pressure induced by ethanol was not affected by the previous administration of losartan (10 mg/kg; p.o. gavage), a selective AT{sub 1} receptor antagonist. Acute ethanol intake increased plasma renin activity (PRA), angiotensin converting enzyme (ACE) activity, plasma angiotensin I (ANG I) and angiotensin II (ANG II) levels. Ethanol induced systemic and vascular oxidative stress, evidenced by increased plasma thiobarbituric acid-reacting substances (TBARS) levels, NAD(P)H oxidase‐mediated vascular generation of superoxide anion and p47phox translocation (cytosol to membrane). These effects were prevented by losartan. Isolated aortas from ethanol-treated rats displayed increased p38MAPK and SAPK/JNK phosphorylation. Losartan inhibited ethanol-induced increase in the phosphorylation of these kinases. Ethanol intake decreased acetylcholine-induced relaxation and increased phenylephrine-induced contraction in endothelium-intact aortas. Ethanol significantly decreased plasma and aortic nitrate levels. These changes in vascular reactivity and in the end product of endogenous nitric oxide metabolism were not affected by losartan. Our study provides novel evidence that acute ethanol intake stimulates RAS activity and induces vascular oxidative stress and redox-signaling activation through AT{sub 1}-dependent mechanisms. These findings highlight the importance of RAS in acute ethanol-induced oxidative damage. -- Highlights: ► Acute ethanol intake stimulates RAS activity and vascular oxidative stress. ► RAS plays a role in acute ethanol-induced oxidative damage via AT{sub 1} receptor activation.

  9. PEST Motif Serine and Tyrosine Phosphorylation Controls Vascular Endothelial Growth Factor Receptor 2 Stability and Downregulation ▿

    Science.gov (United States)

    Meyer, Rosana D.; Srinivasan, Srimathi; Singh, Amrik J.; Mahoney, John E.; Gharahassanlou, Kobra Rezazadeh; Rahimi, Nader

    2011-01-01

    The internalization and degradation of vascular endothelial growth factor receptor 2 (VEGFR-2), a potent angiogenic receptor tyrosine kinase, is a central mechanism for the regulation of the coordinated action of VEGF in angiogenesis. Here, we show that VEGFR-2 is ubiquitinated in response to VEGF, and Lys 48-linked polyubiquitination controls its degradation via the 26S proteosome. The degradation and ubiquitination of VEGFR-2 is controlled by its PEST domain, and the phosphorylation of Ser1188/Ser1191 is required for the ubiquitination of VEGFR-2. F-box-containing β-Trcp1 ubiquitin E3 ligase is recruited to S1188/S1191 VEGFR-2 and mediates the ubiquitination and degradation of VEGFR-2. The PEST domain also controls the activation of p38 mitogen-activated protein kinase (MAPK) through phospho-Y1173. The activation of p38 stabilizes VEGFR-2, and its inactivation accelerates VEGFR-2 downregulation. The VEGFR-2-mediated activation of p38 is established through the protein kinase A (PKA)/MKK6 pathway. PKA is recruited to VEGFR-2 through AKAP1/AKAP149, and its phosphorylation requires Y1173 of VEGFR-2. The study has identified a unique mechanism in which VEGFR-2 stability and degradation is modulated. The PEST domain acts as a dual modulator of VEGFR-2; the phosphorylation of S1188/S1191 controls ubiquitination and degradation via β-Trcp1, where the phosphorylation of Y1173 through PKA/p38 MAPK controls the stability of VEGFR-2. PMID:21402774

  10. Curcumin blocks interleukin-1 signaling in chondrosarcoma cells.

    Directory of Open Access Journals (Sweden)

    Thomas Kalinski

    Full Text Available Interleukin (IL-1 signaling plays an important role in inflammatory processes, but also in malignant processes. The essential downstream event in IL-1 signaling is the activation of nuclear factor (NF-κB, which leads to the expression of several genes that are involved in cell proliferation, invasion, angiogenesis and metastasis, among them VEGF-A. As microenvironment-derived IL-1β is required for invasion and angiogenesis in malignant tumors, also in chondrosarcomas, we investigated IL-1β-induced signal transduction and VEGF-A expression in C3842 and SW1353 chondrosarcoma cells. We additionally performed in vitro angiogenesis assays and NF-κB-related gene expression analyses. Curcumin is a substance which inhibits IL-1 signaling very early by preventing the recruitment of IL-1 receptor associated kinase (IRAK to the IL-1 receptor. We demonstrate that IL-1 signaling and VEGF-A expression are blocked by Curcumin in chondrosarcoma cells. We further show that Curcumin blocks IL-1β-induced angiogenesis and NF-κB-related gene expression. We suppose that IL-1 blockade is an additional treatment option in chondrosarcoma, either by Curcumin, its derivatives or other IL-1 blocking agents.

  11. Insulin receptor substrates 1 and 2 but not Shc can activate the insulin receptor independent of insulin and induce proliferation in CHO-IR cells

    International Nuclear Information System (INIS)

    Niessen, Markus; Jaschinski, Frank; Item, Flurin; McNamara, Morgan P.; Spinas, Giatgen A.; Trueb, Thomas

    2007-01-01

    Ligand-activated insulin receptor (IR) attracts and phosphorylates various substrates such as insulin receptor substrates 1-4 (IRS) and Shc. To investigate how binding affinity for substrate affects signalling we generated chimeric receptors with the β-chain of the insulin receptor containing NPXY motives with different affinities for receptor substrates. We found that the extent of receptor tyrosine phosphorylation positively correlates with binding affinity towards IRS1/2 but not towards Shc. Moreover, overexpression of IRS1 or IRS2 but not of Shc increased IR tyrosine phosphorylation in a dose-dependent manner, also independent of insulin. Molecular truncations of IRS1 revealed that neither the isolated PH and PTB domains nor the C-terminus with the tyrosine phosphorylation sites alone are sufficient for substrate-dependent receptor activation. Overexpression of IRS1 and IRS2 impaired insulin-induced internalization of the IR in a dose-dependent manner suggesting that IRS proteins prevent endosome-associated receptor dephosphorylation/inactivation. IRS1 and IRS2 could therefore target the activated IR to different cellular compartments. Overexpression of IRS1 and IRS2 inhibited insulin-stimulated activation of the MAP kinases Erk1/2 while it increased/induced activation of Akt/PKB. Finally, overexpression of IRS1 and IRS2 but not of Shc induced DNA synthesis in starved CHO-IR cells independent of exogenous growth factors. Our results demonstrate that variations in cellular IRS1 and IRS2 concentration affect insulin signalling both upstream and downstream and that IRS proteins could play instructive rather than just permissive roles in signal transmission

  12. β1-adrenergic receptors activate two distinct signaling pathways in striatal neurons

    Science.gov (United States)

    Meitzen, John; Luoma, Jessie I.; Stern, Christopher M.; Mermelstein, Paul G.

    2010-01-01

    Monoamine action in the dorsal striatum and nucleus accumbens plays essential roles in striatal physiology. Although research often focuses on dopamine and its receptors, norepinephrine and adrenergic receptors are also crucial in regulating striatal function. While noradrenergic neurotransmission has been identified in the striatum, little is known regarding the signaling pathways activated by β-adrenergic receptors in this brain region. Using cultured striatal neurons, we characterized a novel signaling pathway by which activation of β1-adrenergic receptors leads to the rapid phosphorylation of cAMP Response Element Binding Protein (CREB), a transcription-factor implicated as a molecular switch underlying long-term changes in brain function. Norepinephrine-mediated CREB phosphorylation requires β1-adrenergic receptor stimulation of a receptor tyrosine kinase, ultimately leading to the activation of a Ras/Raf/MEK/MAPK/MSK signaling pathway. Activation of β1-adrenergic receptors also induces CRE-dependent transcription and increased c-fos expression. In addition, stimulation of β1-adrenergic receptors produces cAMP production, but surprisingly, β1-adrenergic receptor activation of adenylyl cyclase was not functionally linked to rapid CREB phosphorylation. These findings demonstrate that activation of β1-adrenergic receptors on striatal neurons can stimulate two distinct signaling pathways. These adrenergic actions can produce long-term changes in gene expression, as well as rapidly modulate cellular physiology. By elucidating the mechanisms by which norepinephrine and β1-adrenergic receptor activation affects striatal physiology, we provide the means to more fully understand the role of monoamines in modulating striatal function, specifically how norepinephrine and β1-adrenergic receptors may affect striatal physiology. PMID:21143600

  13. Human interleukin 1β stimulates islet insulin release by a mechanism not dependent on changes in phospholipase C and protein kinase C activities or Ca2+ handling

    International Nuclear Information System (INIS)

    Welsh, N.; Nilsson, T.; Hallberg, A.; Arkhammar, P.; Berggren, P.-O.; Sandler, S.

    1989-01-01

    Isolated islets from adult rats or obese hyperglycemic (ob/ob) mice were incubated with human recombinant interleukin 1β in order to study whether the acute effects of the cytokine on islet insulin release are associated with changes in islet phospholipase C activity, Ca 2+ handling or protein phosphorylation. The cytokine stimulated insulin release both at low and high glucose concentrations during one hour incubations. In shortterm incubations ( 2+ concentration at rest nor that observed subsequent to stimulation with a high concentration of glucose. Furthermore, the endogenous protein kinase C activity, as visualized by immunoprecipitation of a 32 P-labelled substrate for this enzyme, was not altered by interleukin 1β. Separation of 32 P-labelled proteins by means of 2-dimensional gel electrophoresis failed to reveal any specific effects of the cytokine on the total protein phosphorylation activity. These results suggest that the stimulatory effects on insulin release exerted by interleukin 1β are not caused by acute activation of phospholipase C and protein kinase C or by an alternation of islet Ca 2+ handling of the B-cells. (author)

  14. Endocytosis of G protein-coupled receptors is regulated by clathrin light chain phosphorylation.

    Science.gov (United States)

    Ferreira, Filipe; Foley, Matthew; Cooke, Alex; Cunningham, Margaret; Smith, Gemma; Woolley, Robert; Henderson, Graeme; Kelly, Eamonn; Mundell, Stuart; Smythe, Elizabeth

    2012-08-07

    Signaling by transmembrane receptors such as G protein-coupled receptors (GPCRs) occurs at the cell surface and throughout the endocytic pathway, and signaling from the cell surface may differ in magnitude and downstream output from intracellular signaling. As a result, the rate at which signaling molecules traverse the endocytic pathway makes a significant contribution to downstream output. Modulation of the core endocytic machinery facilitates differential uptake of individual cargoes. Clathrin-coated pits are a major entry portal where assembled clathrin forms a lattice around invaginating buds that have captured endocytic cargo. Clathrin assembles into triskelia composed of three clathrin heavy chains and associated clathrin light chains (CLCs). Despite the identification of clathrin-coated pits at the cell surface over 30 years ago, the functions of CLCs in endocytosis have been elusive. In this work, we identify a novel role for CLCs in the regulated endocytosis of specific cargoes. Small interfering RNA-mediated knockdown of either CLCa or CLCb inhibits the uptake of GPCRs. Moreover, we demonstrate that phosphorylation of Ser204 in CLCb is required for efficient endocytosis of a subset of GPCRs and identify G protein-coupled receptor kinase 2 (GRK2) as a kinase that can phosphorylate CLCb on Ser204. Overexpression of CLCb(S204A) specifically inhibits the endocytosis of those GPCRs whose endocytosis is GRK2-dependent. Together, these results indicate that CLCb phosphorylation acts as a discriminator for the endocytosis of specific GPCRs. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Changes in interleukin-1 signal modulators induced by 3,4-methylenedioxymethamphetamine (MDMA: regulation by CB2 receptors and implications for neurotoxicity

    Directory of Open Access Journals (Sweden)

    O'Shea Esther

    2011-05-01

    Full Text Available Abstract Background 3,4-Methylenedioxymethamphetamine (MDMA produces a neuroinflammatory reaction in rat brain characterized by an increase in interleukin-1 beta (IL-1β and microglial activation. The CB2 receptor agonist JWH-015 reduces both these changes and partially protects against MDMA-induced neurotoxicity. We have examined MDMA-induced changes in IL-1 receptor antagonist (IL-1ra levels and IL-1 receptor type I (IL-1RI expression and the effects of JWH-015. The cellular location of IL-1β and IL-1RI was also examined. MDMA-treated animals were given the soluble form of IL-1RI (sIL-1RI and neurotoxic effects examined. Methods Dark Agouti rats received MDMA (12.5 mg/kg, i.p. and levels of IL-1ra and expression of IL-1RI measured 1 h, 3 h or 6 h later. JWH-015 (2.4 mg/kg, i.p. was injected 48 h, 24 h and 0.5 h before MDMA and IL-1ra and IL-1RI measured. For localization studies, animals were sacrificed 1 h or 3 h following MDMA and stained for IL-1β or IL-1RI in combination with neuronal and microglial markers. sIL-1RI (3 μg/animal; i.c.v. was administered 5 min before MDMA and 3 h later. 5-HT transporter density was determined 7 days after MDMA injection. Results MDMA produced an increase in IL-ra levels and a decrease in IL-1RI expression in hypothalamus which was prevented by CB2 receptor activation. IL-1RI expression was localized on neuronal cell bodies while IL-1β expression was observed in microglial cells following MDMA. sIL-1RI potentiated MDMA-induced neurotoxicity. MDMA also increased IgG immunostaining indicating that blood brain-barrier permeability was compromised. Conclusions In summary, MDMA produces changes in IL-1 signal modulators which are modified by CB2 receptor activation. These results indicate that IL-1β may play a partial role in MDMA-induced neurotoxicity.

  16. Tumor-extrinsic discoidin domain receptor 1 promotes mammary tumor growth by regulating adipose stromal interleukin 6 production in mice.

    Science.gov (United States)

    Sun, Xiujie; Gupta, Kshama; Wu, Bogang; Zhang, Deyi; Yuan, Bin; Zhang, Xiaowen; Chiang, Huai-Chin; Zhang, Chi; Curiel, Tyler J; Bendeck, Michelle P; Hursting, Stephen; Hu, Yanfen; Li, Rong

    2018-02-23

    Discoidin domain receptor 1 (DDR1) is a collagen receptor that mediates cell communication with the extracellular matrix (ECM). Aberrant expression and activity of DDR1 in tumor cells are known to promote tumor growth. Although elevated DDR1 levels in the stroma of breast tumors are associated with poor patient outcome, a causal role for tumor-extrinsic DDR1 in cancer promotion remains unclear. Here we report that murine mammary tumor cells transplanted to syngeneic recipient mice in which Ddr1 has been knocked out (KO) grow less robustly than in WT mice. We also found that the tumor-associated stroma in Ddr1- KO mice exhibits reduced collagen deposition compared with the WT controls, supporting a role for stromal DDR1 in ECM remodeling of the tumor microenvironment. Furthermore, the stromal-vascular fraction (SVF) of Ddr1 knockout adipose tissue, which contains committed adipose stem/progenitor cells and preadipocytes, was impaired in its ability to stimulate tumor cell migration and invasion. Cytokine array-based screening identified interleukin 6 (IL-6) as a cytokine secreted by the SVF in a DDR1-dependent manner. SVF-produced IL-6 is important for SVF-stimulated tumor cell invasion in vitro , and, using antibody-based neutralization, we show that tumor promotion by IL-6 in vivo requires DDR1. In conclusion, our work demonstrates a previously unrecognized function of DDR1 in promoting tumor growth. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Tyrosine phosphorylation of Grb14 by Tie2

    Directory of Open Access Journals (Sweden)

    Dumont Daniel J

    2010-10-01

    Full Text Available Abstract Background Growth factor receptor bound (Grb proteins 7, 10 and 14 are a family of structurally related multi-domain adaptor proteins involved in a variety of biological processes. Grb7, 10 and 14 are known to become serine and/or threonine phosphorylated in response to growth factor (GF stimulation. Grb7 and 10 have also been shown to become tyrosine phosphorylated under certain conditions. Under experimental conditions Grb7 is tyrosine phosphorylated by the Tie2/Tie-2/Tek angiogenic receptor tyrosine kinase (RTK. Furthermore, Grb14 has also been shown to interact with Tie2, however tyrosine phosphorylation of this Grb family member has yet to be reported. Results Here we report for the first time tyrosine phosphorylation of Grb14. This phosphorylation requires a kinase competent Tie2 as well as intact tyrosines 1100 and 1106 (Y1100 and Y1106 on the receptor. Furthermore, a complete SH2 domain on Grb14 is required for Grb14 tyrosine phosphorylation by Tie2. Grb14 was also able to become tyrosine phosphorylated in primary endothelial cells when treated with a soluble and potent variant of the Tie2 ligand, cartilage oligomeric matrix protein (COMP Ang1. Conclusion Our results show that Grb14, like its family members Grb7 and Grb10, is able to be tyrosine phosphorylated. Furthermore, our data indicate a role for Grb14 in endothelial signaling downstream of the Tie2 receptor.

  18. Interleukin-6 receptor pathways in coronary heart disease: a collaborative meta-analysis of 82 studies

    NARCIS (Netherlands)

    Sarwar, Nadeem; Butterworth, Adam S.; Freitag, Daniel F.; Gregson, John; Willeit, Peter; Gorman, Donal N.; Gao, Pei; Saleheen, Danish; Rendon, Augusto; Nelson, Christopher P.; Braund, Peter S.; Hall, Alistair S.; Chasman, Daniel I.; Tybjærg-Hansen, Anne; Chambers, John C.; Benjamin, Emelia J.; Franks, Paul W.; Clarke, Robert; Wilde, Arthur A. M.; Trip, Mieke D.; Steri, Maristella; Witteman, Jacqueline C. M.; Qi, Lu; van der Schoot, C. Ellen; de Faire, Ulf; Erdmann, Jeanette; Stringham, Heather M.; Koenig, Wolfgang; Rader, Daniel J.; Melzer, David; Reich, David; Psaty, Bruce M.; Kleber, Marcus E.; Panagiotakos, Demosthenes B.; Willeit, Johann; Wennberg, Patrik; Woodward, Mark; Adamovic, Svetlana; Rimm, Eric B.; Meade, Tom W.; Gillum, Richard F.; Shaffer, Jonathan A.; Hofman, Albert; Onat, Altan; Sundström, Johan; Wassertheil-Smoller, Sylvia; Mellström, Dan; Gallacher, John; Cushman, Mary; Tracy, Russell P.; Kauhanen, Jussi; Karlsson, Magnus; Salonen, Jukka T.; Wilhelmsen, Lars; Amouyel, Philippe; Cantin, Bernard; Best, Lyle G.; Ben-Shlomo, Yoav; Manson, JoAnn E.; Davey-Smith, George; de Bakker, Paul I. W.; O'Donnell, Christopher J.; Wilson, James F.; Wilson, Anthony G.; Assimes, Themistocles L.; Jansson, John-Olov; Ohlsson, Claes; Tivesten, Åsa; Ljunggren, Östen; Reilly, Muredach P.; Hamsten, Anders; Ingelsson, Erik; Cambien, Francois; Hung, Joseph; Thomas, G. Neil; Boehnke, Michael; Schunkert, Heribert; Asselbergs, Folkert W.; Kastelein, John J. P.; Gudnason, Vilmundur; Salomaa, Veikko; Harris, Tamara B.; Kooner, Jaspal S.; Allin, Kristine H.; Nordestgaard, Børge G.; Hopewell, Jemma C.; Goodall, Alison H.; Ridker, Paul M.; Hólm, Hilma; Watkins, Hugh; Ouwehand, Willem H.; Samani, Nilesh J.; Kaptoge, Stephen; Di Angelantonio, Emanuele; Harari, Olivier; Danesh, John; Quertermous, Thomas; Go, Alan S.; Hlatky, Mark A.; Knowles, Joshua W.; Smith, Albert V.; Chrysohoou, Christina; Pitsavos, Christos; Stefanadis, Christodoulos; Balmforth, Anthony J.; Thompson, John R.; Sivapalaratnam, Suthesh; Maiwald, Stephani; Basart, Hanneke; Motazacker, Mahdi; de Jong, Jonas S. S. G.; Dekker, Lucas R. C.; Tanck, Michael; Bezzina, Connie R.; Whincup, Peter H.; Morris, Richard W.; Wannamethee, S. Goya; Kiechl, Stefan; Yarnell, John W. G.; Lowe, Gordon; Rumley, Ann; Mukamal, Kenneth J.; Havulinna, Aki S.; Lokki, Marja-Liisa; Nieminen, Markku S.; Ripatti, Samuli; Sinisalo, Juha; McQuillan, Brendan M.; Beilby, John P.; Thompson, Peter L.; Thorleifsson, Guðmar; Thorgeirsson, Guðmundur; Thorsteinsdóttir, Unnur; Stefansson, Kari; Jula, Antti; Männistö, Satu; Perola, Markus; Tikkanen, Emmi; Boer, Jolanda M. A.; Onland-Moret, N. Charlott; van der Schouw, Yvonne T.; Verschuren, W. M. Monique; Jansson, Jan-Håkan; Dupuis, Josée; Fontes, João D.; Yin, Xiaoyan; Tuomilehto, Jaakko; Koenig, Inke R.; Nahrstaedt, Janja; Loley, Christina; Stark, Klaus; Willenborg, Christina; Hengstenberg, Christian; Schreiber, Stefan; Preuss, Michael; Barroso, Inês; Hallmans, Göran; Shungin, Dmitry; Cheng, Kar Keung; Lam, Tai Hing; Jiang, Chao Chiang; Pai, Jennifer; Collins, Rory; Parish, Sarah; Armitage, Jane; Jackson, Anne; Hveem, Kristian; Wiggins, Kerri L.; Heckbert, Susan R.; Smith, Nicholas L.; Bis, Joshua C.; Ferrucci, Luigi; Guralnik, Jack M.; Bandinelli, Stefania; Singleton, Andrew B.; Tuomainen, Tomi-Pekka; Kurl, Sudhir; Zhang, Weihua; Kooner, Angad S.; Das, Debashis; März, Winfried; Scharnagl, Hubert; Böhm, Bernhard O.; Winkelmann, Bernhard R.; Folsom, Aaron R.; Shea, Steven J.; Laakso, Markku; Kuusisto, Johanna; Baumert, Jens; Thorand, Barbara; Illig, Thomas; Meisinger, Christa; Rosengren, Annika; Karlsson, Magnus K.; Hu, Frank B.; Hankinson, Susan E.; Davidson, Karina W.; Fraser, Ross; Wild, Sarah; Campbell, Harry; Qasim, Atif; Qu, Liming; Li, Mingyao; Lind, Lars; Syvänen, Ann-Christine; Arveiler, Dominique; Farrall, Martin; Peden, John F.; Deloukas, Panos; Sheikh, Nasir; Rasheed, Asif; Dagenais, Gilles R.; Dehghan, Abbas; van Duijn, Cornelia M.; Uitterlinden, Andre G.; Abecasis, Goncalo R.; Cucca, Francesco; Sanna, Serena; Uda, Manuela; Schlessinger, David; Sabater-Lleal, Maria; Silveira, Angela; Gigante, Bruna; Howard, Barbara V.; Basu, Samar; Rose, Lynda M.; Buring, Julie

    2012-01-01

    Background Persistent inflammation has been proposed to contribute to various stages in the pathogenesis of cardiovascular disease. Interleukin-6 receptor (IL6R) signalling propagates downstream inflammation cascades. To assess whether this pathway is causally relevant to coronary heart disease, we

  19. Amniotic-fluid-derived mesenchymal stem cells overexpressing interleukin-1 receptor antagonist improve fulminant hepatic failure.

    Directory of Open Access Journals (Sweden)

    Yu-Bao Zheng

    Full Text Available Uncontrolled hepatic immunoactivation is regarded as the primary pathological mechanism of fulminant hepatic failure (FHF. The major acute-phase mediators associated with FHF, including IL-1β, IL-6, and TNF-α, impair the regeneration of liver cells and stem cell grafts. Amniotic-fluid-derived mesenchymal stem cells (AF-MSCs have the capacity, under specific conditions, to differentiate into hepatocytes. Interleukin-1-receptor antagonist (IL-1Ra plays an anti-inflammatory and anti-apoptotic role in acute and chronic inflammation, and has been used in many experimental and clinical applications. In the present study, we implanted IL-1Ra-expressing AF-MSCs into injured liver via the portal vein, using D-galactosamine-induced FHF in a rat model. IL-1Ra expression, hepatic injury, liver regeneration, cytokines (IL-1β, IL-6, and animal survival were assessed after cell transplantation. Our results showed that AF-MSCs over-expressing IL-1Ra prevented liver failure and reduced mortality in rats with FHF. These animals also exhibited improved liver function and increased survival rates after injection with these cells. Using green fluorescent protein as a marker, we demonstrated that the engrafted cells and their progeny were incorporated into injured livers and produced albumin. This study suggests that AF-MSCs genetically modified to over-express IL-1Ra can be implanted into the injured liver to provide a novel therapeutic approach to the treatment of FHF.

  20. Understanding the Differential Selectivity of Arrestins toward the Phosphorylation State of the Receptor

    NARCIS (Netherlands)

    Sensoy, Ozge; de Sousa Moreira, Irina; Morra, Giulia

    2016-01-01

    Proteins in the arrestin family exhibit a conserved structural fold that nevertheless allows for significant differences in their selectivity for G-protein coupled receptors (GPCRs) and their phosphorylation states. To reveal the mechanism of activation that prepares arrestin for selective

  1. Similarities and differences in signal transduction by interleukin 4 and interleukin 13: analysis of Janus kinase activation.

    Science.gov (United States)

    Keegan, A D; Johnston, J A; Tortolani, P J; McReynolds, L J; Kinzer, C; O'Shea, J J; Paul, W E

    1995-08-15

    The cytokines interleukin (IL) 4 and IL-13 induce many of the same biological responses, including class switching to IgE and induction of major histocompatibility complex class II antigens and CD23 on human B cells. It has recently been shown that IL-4 induces the tyrosine phosphorylation of a 170-kDa protein, a substrate called 4PS, and of the Janus kinase (JAK) family members JAK1 and JAK3. Because IL-13 has many functional effects similar to those of IL-4, we compared the ability of IL-4 and IL-13 to activate these signaling molecules in the human multifactor-dependent cell line TF-1. In this report we demonstrate that both IL-4 and IL-13 induced the tyrosine phosphorylation of 4PS and JAK1. Interestingly, although IL-4 induced the tyrosine phosphorylation of JAK3, we did not detect JAK3 phosphorylation in response to IL-13. These data suggest that IL-4 and IL-13 signal in similar ways via the activation of JAK1 and 4PS. However, our data further indicate that there are significant differences because IL-13 does not activate JAK3.

  2. PTP1B is a negative regulator of interleukin 4–induced STAT6 signaling

    Science.gov (United States)

    Lu, Xiaoqing; Malumbres, Raquel; Shields, Benjamin; Jiang, Xiaoyu; Sarosiek, Kristopher A.; Natkunam, Yasodha

    2008-01-01

    Protein tyrosine phosphatase 1B (PTP1B) is a ubiquitously expressed enzyme shown to negatively regulate multiple tyrosine phosphorylation-dependent signaling pathways. PTP1B can modulate cytokine signaling pathways by dephosphorylating JAK2, TYK2, and STAT5a/b. Herein, we report that phosphorylated STAT6 may serve as a cytoplasmic substrate for PTP1B. Overexpression of PTP1B led to STAT6 dephosphorylation and the suppression of STAT6 transcriptional activity, whereas PTP1B knockdown or deficiency augmented IL-4–induced STAT6 signaling. Pretreatment of these cells with the PTK inhibitor staurosporine led to sustained STAT6 phosphorylation consistent with STAT6 serving as a direct substrate of PTP1B. Furthermore, PTP1B-D181A “substrate-trapping” mutants formed stable complexes with phosphorylated STAT6 in a cellular context and endogenous PTP1B and STAT6 interacted in an interleukin 4 (IL-4)–inducible manner. We delineate a new negative regulatory loop of IL-4–JAK-STAT6 signaling. We demonstrate that IL-4 induces PTP1B mRNA expression in a phosphatidylinositol 3-kinase–dependent manner and enhances PTP1B protein stability to suppress IL-4–induced STAT6 signaling. Finally, we show that PTP1B expression may be preferentially elevated in activated B cell–like diffuse large B-cell lymphomas. These observations identify a novel regulatory loop for the regulation of IL-4–induced STAT6 signaling that may have important implications in both neoplastic and inflammatory processes. PMID:18716132

  3. Homologous desensitization of adenylate cyclase: the role of β-adrenergic receptor phosphorylation and dephosphorylation

    International Nuclear Information System (INIS)

    Sibley, D.R.; Strasser, R.H.; Daniel, K.; Lefkowitz, R.J.

    1986-01-01

    The authors utilized the frog erythrocyte (FE) as a β-adreneric receptor (βAR) model system in which to study homologous desensitization. Preincubation with isoproterenol (ISO) leads to a 50% decline in ISO-stimulated adenylate cyclase (AC) activity without significant changes in basal, PGE 1 -, NaF-, GppNHp-, forskolin-, or MnCl 2 -stimulated AC activities. ISO treatment also induces the sequestration of βAR from the cell surface as evidenced by a 35% decline in [ 3 H]CGP-12177 binding sites on the surface of intact FE. Treatment of intact FE with ISO also promotes βAR phosphorylation to 2 mol PO 4 /mol of βAR. At 25 0 C, the time courses of ISO-induced AC desensitization, βAR sequestration and βAR phosphorylation are identical occurring without a lag and exhibiting a t 1/2 of 30 min and a maximal response at 2.5 hrs. The sequestered βAR can be partially recovered upon cell lysis in a light membrane fraction (LMF), separable from the plasma membranes using sucrose gradients or differential centrifugation. βAR phosphorylation is reversed in the sequestered LMF exhibiting a PO 4 /βAR stoichiometry of 0.7 mol/mol - similar to that observed under basal conditions. These data suggest that phosphorylation of βAR in the plasma membrane promotes their translocation away from the cell surface into a sequestered membrane domain where the phosphorylation is reversed, thus, enabling the return of βAR back to the cell surface and recoupling with AC

  4. The history of fever, leukocytic pyrogen and interleukin-1.

    Science.gov (United States)

    Dinarello, Charles A

    2015-01-01

    There has been great progress in the 30 y since the reporting in 1984 of the cDNA for interleukin1 (IL1) β in the human and IL1α in the mouse. However, the history of IL1 begins in the early 1940s with investigations into the nature of an endogenous fever-producing protein released rabbit peritoneal neutrophils. Most researchers in immunology today are unaware that the field of cytokines, particularly the field of inflammatory cytokines. Toll-like receptors and innate immunity traces back to studies on fever. Researchers in infectious diseases wanted to know about an endogenous protein that caused fever, independent of infection. The endogenous fever-producing protein was called by various names: granulocyte, endogenous or leukocytic pyrogen. It is a fascinating and sometimes controversial story for biology and medicine and for the treatment of inflammatory diseases. Few imagined that this fever-producing protein would play such a major role in nearly every cell and in most diseases. This paper reviews the true background and milestones of interleukin1 from the purification of leukocytic pyrogen to the first cDNA of IL1β and the validation of cytokine biology from ill-defined factors to its present day importance.

  5. An anti-interleukin-2 receptor drug attenuates T- helper 1 lymphocytes-mediated inflammation in an acute model of endotoxin-induced uveitis.

    Directory of Open Access Journals (Sweden)

    Salvador Mérida

    Full Text Available The aim of the present study was to evaluate the anti-inflammatory efficacy of Daclizumab, an anti-interleukin-2 receptor drug, in an experimental uveitis model upon a subcutaneous injection of lipopolysaccharide into Lewis rats, a valuable model for ocular acute inflammatory processes. The integrity of the blood-aqueous barrier was assessed 24 h after endotoxin-induced uveitis by evaluating two parameters: cell count and protein concentration in aqueous humors. The histopathology of all the ocular structures (cornea, lens, sclera, choroid, retina, uvea, and anterior and posterior chambers was also considered. Enzyme-linked immunosorbent assays of the aqueous humor samples were performed to quantify the levels of the different chemokine and cytokine proteins. Similarly, a biochemical analysis of oxidative stress-related markers was also assessed. The inflammation observed in the anterior chamber of the eyes when Daclizumab was administered with endotoxin was largely prevented since the aqueous humor protein concentration substantially lowered concomitantly with a significant reduction in the uveal and vitreous histopathological grading. Th1 lymphocytes-related cytokines, such as Interleukin-2 and Interferon-γ, also significantly reduced with related anti-oxidant systems recovery. Daclizumab treatment in endotoxin-induced uveitis reduced Th1 lymphocytes-related cytokines, such as Interleukin-2 and Interferon gamma, by about 60-70% and presented a preventive role in endotoxin-induced oxidative stress. This antioxidant protective effect of Daclizumab may be related to several of the observed Daclizumab effects in our study, including IL-6 cytokine regulatory properties and a substantial concomitant drop in INFγ. Concurrently, Daclizumab treatment triggered a significant reduction in both the uveal histopathological grading and protein concentration in aqueous humors, but not in cellular infiltration.

  6. Dual Mechanism of Interleukin-3 Receptor Blockade by an Anti-Cancer Antibody

    Directory of Open Access Journals (Sweden)

    Sophie E. Broughton

    2014-07-01

    Full Text Available Interleukin-3 (IL-3 is an activated T cell product that bridges innate and adaptive immunity and contributes to several immunopathologies. Here, we report the crystal structure of the IL-3 receptor α chain (IL3Rα in complex with the anti-leukemia antibody CSL362 that reveals the N-terminal domain (NTD, a domain also present in the granulocyte-macrophage colony-stimulating factor (GM-CSF, IL-5, and IL-13 receptors, adopting unique “open” and classical “closed” conformations. Although extensive mutational analyses of the NTD epitope of CSL362 show minor overlap with the IL-3 binding site, CSL362 only inhibits IL-3 binding to the closed conformation, indicating alternative mechanisms for blocking IL-3 signaling. Significantly, whereas “open-like” IL3Rα mutants can simultaneously bind IL-3 and CSL362, CSL362 still prevents the assembly of a higher-order IL-3 receptor-signaling complex. The discovery of open forms of cytokine receptors provides the framework for development of potent antibodies that can achieve a “double hit” cytokine receptor blockade.

  7. Identification of Cyclin-dependent Kinase 1 Specific Phosphorylation Sites by an In Vitro Kinase Assay.

    Science.gov (United States)

    Cui, Heying; Loftus, Kyle M; Noell, Crystal R; Solmaz, Sozanne R

    2018-05-03

    Cyclin-dependent kinase 1 (Cdk1) is a master controller for the cell cycle in all eukaryotes and phosphorylates an estimated 8 - 13% of the proteome; however, the number of identified targets for Cdk1, particularly in human cells is still low. The identification of Cdk1-specific phosphorylation sites is important, as they provide mechanistic insights into how Cdk1 controls the cell cycle. Cell cycle regulation is critical for faithful chromosome segregation, and defects in this complicated process lead to chromosomal aberrations and cancer. Here, we describe an in vitro kinase assay that is used to identify Cdk1-specific phosphorylation sites. In this assay, a purified protein is phosphorylated in vitro by commercially available human Cdk1/cyclin B. Successful phosphorylation is confirmed by SDS-PAGE, and phosphorylation sites are subsequently identified by mass spectrometry. We also describe purification protocols that yield highly pure and homogeneous protein preparations suitable for the kinase assay, and a binding assay for the functional verification of the identified phosphorylation sites, which probes the interaction between a classical nuclear localization signal (cNLS) and its nuclear transport receptor karyopherin α. To aid with experimental design, we review approaches for the prediction of Cdk1-specific phosphorylation sites from protein sequences. Together these protocols present a very powerful approach that yields Cdk1-specific phosphorylation sites and enables mechanistic studies into how Cdk1 controls the cell cycle. Since this method relies on purified proteins, it can be applied to any model organism and yields reliable results, especially when combined with cell functional studies.

  8. Association between interleukin 1 receptor antagonist gene 86-bp VNTR polymorphism and sepsis: a meta-analysis.

    Science.gov (United States)

    Fang, Fang; Pan, Jian; Li, Yiping; Xu, Lixiao; Su, Guanghao; Li, Gang; Wang, Jian

    2015-01-01

    Many studies have focused on the relationship between interleukin 1 receptor antagonist (IL1RN) gene 86-bp VNTR polymorphism and sepsis, but the results remain inconsistent. Thus, a meta-analysis was carried out to derive a more precise estimation of the association between IL1RN 86-bp VNTR polymorphism and risk of sepsis and sepsis-related mortality. Relevant publications were searched in several widely used databases and six eligible studies were included in the meta-analysis. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to evaluate the strength of the association between IL1RN 86-bp VNTR polymorphism and risk of sepsis and sepsis-related mortality. Significant associations between IL1RN 86-bp VNTR polymorphism and sepsis risk were observed in both overall meta-analysis for L2 versus 22 (OR=0.75, 95% CI=0.59-0.94) and severe sepsis subgroup for LL+L2 versus 22 (OR=0.67, 95% CI=0.47-0.93). L stands for long alleles containing three to six repeats; 2 stands for short allele containing two repeats. However, no significant sepsis mortality variation was detected for all genetic models. According to the results of our meta-analysis, the IL1RN 86-bp VNTR polymorphism probably associates with sepsis risk but not with sepsis-related mortality. Copyright © 2014. Published by Elsevier Inc.

  9. Receptor tyrosine phosphatase R-PTP-alpha is tyrosine-phosphorylated and associated with the adaptor protein Grb2

    DEFF Research Database (Denmark)

    Su, J; Batzer, A; Sap, J

    1994-01-01

    Receptor tyrosine phosphatases (R-PTPases) have generated interest because of their suspected involvement in cellular signal transduction. The adaptor protein Grb2 has been implicated in coupling receptor tyrosine kinases to Ras. We report that a ubiquitous R-PTPase, R-PTP-alpha, is tyrosine......-phosphorylated and associated in vivo with the Grb2 protein. This association can be reproduced in stably and transiently transfected cells, as well as in vitro using recombinant Grb2 protein. Association requires the presence of an intact SH2 domain in Grb2, as well as tyrosine phosphorylation of R-PTP-alpha. This observation...... links a receptor tyrosine phosphatase with a key component of a central cellular signalling pathway and provides a basis for addressing R-PTP-alpha function....

  10. Cardiometabolic effects of genetic upregulation of the interleukin 1 receptor antagonist: A Mendelian randomisation analysis

    NARCIS (Netherlands)

    C.M. Freitag (Christine); A.S. Butterworth (Adam); J. Willeit (Johann); J.M.M. Howson (Joanna M.M.); S. Burgess (Stephen); S. Kaptoge (Stephen); R. Young (Robin); W.K. Ho (Weang Kee); A.M. Wood (Angela); M. Sweeting (Michael); S. Spackman (Sarah); J.R. Staley (James R.); A. Ramond (Anna); E. Harshfield (Eric); S.F. Nielsen (Sune); P. Grande (Peer); L.A. Lange (Leslie); M.J. Bown (Matthew J.); G.T. Jones (Gregory); R.A. Scott (Robert); S. Bevan (Steve); E. Porcu (Eleonora); G. Thorleifsson (Gudmar); L. Zeng (Lingyao); T. Kessler (Thorsten); M. Nikpay (Majid); R. Do (Ron); W. Zhang (Weihua); J. Hopewell; M.E. Kleber (Marcus); G. Delgado; C.P. Nelson (Christopher P.); A. Goel (Anuj); J.C. Bis (Joshua); A. Dehghan (Abbas); S. Ligthart (Symen); G.D. Smith; L. Qu (Liming); F.N.G. Van 'T Hof (Femke); P.I.W. de Bakker (Paul); A.F. Baas (Annette); A.M. van Rij (Andre); G. Tromp (Gerard); H. Kuivaniemi (Helena); M.D. Ritchie (Marylyn D.); S.S. Verma (Shefali S.); D.C. Crawford (Dana); J. Malinowski (Jennifer); M. de Andrade (Mariza); I. Kullo (Iftikhar); P.L. Peissig (Peggy L.); C.A. McCarty (Catherine A.); E.P. Bottinger (Erwin); R.F. Gottesman (Rebecca); D.R. Crosslin (David); D.S. Carrell (David); L.J. Rasmussen-Torvik (Laura); J.A. Pacheco (Jennifer A.); J. Huang (Jie); N.J. Timpson (Nicholas); J. Kettunen (Johannes); M. Ala-Korpela (Mika); G.F. Mitchell (Gary); A. Parsa (Afshin); I.B. Wilkinson (Ian B.); M. Gorski (Mathias); Y. Li (Yong); N. Franceschini (Nora); M.F. Keller (Margaux); S.K. Ganesh (Santhi); C.D. Langefeld (Carl); L. Bruijn (Lucie); M.A. Brown (Matthew); D.M. Evans (David M.); S. Baltic (Svetlana); M.A. Ferreira (Manuel); H. Baurecht (Hansjörg); S. Weidinger (Stephan); A. Franke (Andre); S.A. Lubitz (Steven); M. Müller-Nurasyid (Martina); J.F. Felix (Janine); N.L. Smith (Nicholas); M. Sudman (Marc); S.D. Thompson (Susan D.); E. Zeggini (Eleftheria); K. Panoutsopoulou (Kalliope); M.A. Nalls (Michael); A. Singleton (Andrew); C. Polychronakos (Constantin); J.P. Bradfield (Jonathan); H. Hakonarson (Hakon); D.F. Easton (Douglas); D. Thompson (Deborah); I.P. Tomlinson (Ian); M. Dunlop (Malcolm); K. Hemminki (Kari); G. Morgan (Gareth); T. Eisen (Timothy); H. Goldschmidt (Hartmut); J.M. Allan (James); M. Henrion (Marc); N. Whiffin (Nicola); Y. Wang (Yufei); D. Chubb (Daniel); M.M. Iles (Mark M.); D.T. Bishop (David Timothy); M.H. Law (Matthew H.); N. Hayward (Nick); Y. Luo (Yang); S. Nejentsev (Sergey); M. Barbalic (maja); D. Crossman (David); S. Sanna (Serena); N. Soranzo (Nicole); H.S. Markus (Hugh); N.J. Wareham (Nick); D.J. Rader (Daniel); M.P. Reilly (Muredach); T.L. Assimes (Themistocles); T.B. Harris (Tamara B.); A. Hofman (Albert); O.H. Franco (Oscar); V. Gudnason (Vilmundur); R.P. Tracy (Russell); B.M. Psaty (Bruce); M. Farrall (Martin); H. Watkins (Hugh); A.S. Hall (Alistair); N.J. Samani (Nilesh); W. März (Winfried); R. Clarke (Robert); F.S. Collins (Francis); J.S. Kooner (Jaspal S.); J.C. Chambers (John C.); S. Kathiresan (Sekar); R. McPherson (Ruth); J. Erdmann (Jeanette); A. Kastrati (Adnan); H. Schunkert (Heribert); J-A. Zwart (John-Anker); U. Thorsteinsdottir (Unnur); J. Walston (Jeremy); A. Tybjaerg-Hansen; D.S. Alam (Dewan S.); A. Al Shafi Majumder (Abdullah); E.D. Angelantonio (Emanuele Di); R. Chowdhury (Rajiv); B.G. Nordestgaard (Børge); D. Saleheen; S.G. Thompson (Simon); J. Danesh (John); R. Houlston (Richard)

    2015-01-01

    textabstractTo investigate potential cardiovascular and other effects of long-term pharmacological interleukin 1 (IL-1) inhibition, we studied genetic variants that produce inhibition of IL-1, a master regulator of inflammation. Methods: We created a genetic score combining the effects of alleles of

  11. Cardiometabolic effects of genetic upregulation of the interleukin 1 receptor antagonist : A Mendelian randomisation analysis

    NARCIS (Netherlands)

    Freitag, Daniel; Butterworth, Adam S.; Willeit, Peter; Howson, Joanna M M; Burgess, Stephen; Kaptoge, Stephen; Young, Robin; Ho, Weang Kee; Wood, Angela M.; Sweeting, Michael; Spackman, Sarah; Staley, James R.; Ramond, Anna; Harshfield, Eric; Nielsen, Sune F.; Grande, Peer; Lange, Leslie A.; Bown, Matthew J.; Jones, Gregory T.; Scott, Robert A.; Bevan, Steve; Porcu, Eleonora; Thorleifsson, Gudmar; Zeng, Lingyao; Kessler, Thorsten; Nikpay, Majid; Do, Ron; Zhang, Weihua; Hopewell, Jemma C.; Kleber, Marcus; Delgado, Graciela E.; Nelson, Christopher P.; Goel, Anuj; Bis, Joshua C.; Dehghan, Abbas; Ligthart, Symen; Smith, Albert V.; Qu, Liming; van 't Hof, Femke N G; de Bakker, Paul I W; Baas, Annette F.; van Rij, Andre; Tromp, Gerard; Kuivaniemi, Helena; Ritchie, Marylyn D.; Verma, Shefali S.; Crawford, Dana C.; Malinowski, Jennifer; de Andrade, Mariza; Kullo, Iftikhar J.; Peissig, Peggy L.; McCarty, Catherine A.; Böttinger, Erwin P.; Gottesman, Omri; Crosslin, David R.; Carrell, David S.; Rasmussen-Torvik, Laura J.; Pacheco, Jennifer A.; Huang, Jie; Timpson, Nicholas J.; Kettunen, Johannes; Ala-Korpela, Mika; Mitchell, Gary F.; Parsa, Afshin; Wilkinson, Ian B.; Gorski, Mathias; Li, Yong; Franceschini, Nora; Keller, Margaux F.; Ganesh, Santhi K.; Langefeld, Carl D.; Bruijn, Lucie; Brown, Matthew A.; Evans, David M.; Baltic, Svetlana; Ferreira, Manuel A.; Baurecht, Hansjörg; Weidinger, Stephan; Franke, Andre; Lubitz, Steven A.; Müller-Nurasyid, Martina; Felix, Janine F.; Smith, Nicholas L.; Sudman, Marc; Thompson, Susan D.; Zeggini, Eleftheria; Panoutsopoulou, Kalliope; Nalls, Mike A.; Singleton, Andrew; Polychronakos, Constantin; Bradfield, Jonathan P.; Hakonarson, Hakon; Easton, Douglas F.; Thompson, Deborah; Tomlinson, Ian P.; Dunlop, Malcolm; Hemminki, Kari; Morgan, Gareth; Eisen, Timothy; Goldschmidt, Hartmut; Allan, James M.; Henrion, Marc; Whiffin, Nicola; Wang, Yufei; Chubb, Daniel; Iles, Mark M.; Bishop, D. Timothy; Law, Matthew H.; Hayward, Nicholas K.; Luo, Yang; Nejentsev, Sergey; Barbalic, Maja; Crossman, David; Sanna, Serena; Soranzo, Nicole; Markus, Hugh S.; Wareham, Nicholas J.; Rader, Daniel J.; Reilly, Muredach; Assimes, Themistocles; Harris, Tamara B.; Hofman, Albert; Franco, Oscar H.; Gudnason, Vilmundur; Tracy, Russell; Psaty, Bruce M.; Farrall, Martin; Watkins, Hugh; Hall, Alistair S.; Samani, Nilesh J.; März, Winfried; Clarke, Robert; Collins, Rory; Kooner, Jaspal S.; Chambers, John C.; Kathiresan, Sekar; McPherson, Ruth; Erdmann, Jeanette; Kastrati, Adnan; Schunkert, Heribert; Stefánsson, Kári; Thorsteinsdottir, Unnur; Walston, Jeremy D.; Tybjærg-Hansen, Anne; Alam, Dewan S.; Al Shafi Majumder, Abdullah; Angelantonio, Emanuele Di; Chowdhury, Rajiv; Nordestgaard, Børge G.; Saleheen, Danish; Thompson, Simon G.; Danesh, John; Houlston, Richard S.

    2015-01-01

    To investigate potential cardiovascular and other effects of long-term pharmacological interleukin 1 (IL-1) inhibition, we studied genetic variants that produce inhibition of IL-1, a master regulator of inflammation. Methods: We created a genetic score combining the effects of alleles of two common

  12. Tyr721 regulates specific binding of the CSF-1 receptor kinase insert to PI 3'-kinase SH2 domains: a model for SH2-mediated receptor-target interactions.

    Science.gov (United States)

    Reedijk, M; Liu, X; van der Geer, P; Letwin, K; Waterfield, M D; Hunter, T; Pawson, T

    1992-01-01

    Efficient binding of active phosphatidylinositol (PI) 3'-kinase to the autophosphorylated macrophage colony stimulating factor receptor (CSF-1R) requires the noncatalytic kinase insert (KI) region of the receptor. To test whether this region could function independently to bind PI 3'-kinase, the isolated CSF-1R KI was expressed in Escherichia coli, and was inducibly phosphorylated on tyrosine. The tyrosine phosphorylated form of the CSF-1R KI bound PI 3'-kinase in vitro, whereas the unphosphorylated form had no binding activity. The p85 alpha subunit of PI 3'-kinase contains two Src homology (SH)2 domains, which are implicated in the interactions of signalling proteins with activated receptors. Bacterially expressed p85 alpha SH2 domains complexed in vitro with the tyrosine phosphorylated CSF-1R KI. Binding of the CSF-1R KI to PI 3'-kinase activity, and to the p85 alpha SH2 domains, required phosphorylation of Tyr721 within the KI domain, but was independent of phosphorylation at Tyr697 and Tyr706. Tyr721 was also critical for the association of activated CSF-1R with PI 3'-kinase in mammalian cells. Complex formation between the CSF-1R and PI 3'-kinase can therefore be reconstructed in vitro in a specific interaction involving the phosphorylated receptor KI and the SH2 domains of p85 alpha. Images PMID:1314163

  13. Nitric oxide generated by ionizing radiation and EGF is implicated in EGF receptor phosphorylation in A549 lung carcinoma cells

    International Nuclear Information System (INIS)

    Park, In Chul; Lee, Hyung Chahn; Rhee, Chang Hun; Hong, Seok Il

    2004-01-01

    Although it has been demonstrated that ionizing radiation (IR) control various cell functions in a different cell types, the mechanisms of its action via NO are not well understood. NO may potentially affect every type of mammalian cells, owing to its ubiquitous production and participate in the control of cell proliferation in a great variety of cell types. The epidermal growth factor (EGF) receptor is a transmembrane glycoprotein of Mr 170,000. When EGF binds to its receptor, the receptor is dimerized and autophosphorylated at the carboxyl-terminal tyrosine 992, 1608, 1086, 1148 and 1173. This phosphorylated receptor initiates a series of signal tranduction events through interacting proteins of SH2 family including Shc, Grb2 and Sos, which in turn trigger ativation of MAPK cascades. Although the number of signaling events mediated by IR-induced NO is growing, it is still unclear how NO activate cellular signaling events. Thus, we examined the effect of NO on cellular phosphorylation and found that NO was produced by ionizing radiation in A549 lung adenocarcinoma cells and enhances the unique tyrosine phosphorylation on EGF receptor

  14. No linkage and association of atopy to chromosome 16 including the interleukin-4 receptor gene

    DEFF Research Database (Denmark)

    Haagerup, A; Bjerke, T; Schiøtz, P O

    2001-01-01

    BACKGROUND: Several susceptibility genes for atopy have been suggested in recent years. Few have been investigated as intensively as the interleukin-4-receptor alpha (IL4Ralpha) gene on chromosome 16. The results remain in dispute. Therefore, in a robust design, we tested for association of type ...

  15. Quantitation of multisite EGF receptor phosphorylation using mass spectrometry and a novel normalization approach

    DEFF Research Database (Denmark)

    Erba, Elisabetta Boeri; Matthiesen, Rune; Bunkenborg, Jakob

    2007-01-01

    Using stable isotope labeling and mass spectrometry, we performed a sensitive, quantitative analysis of multiple phosphorylation sites of the epidermal growth factor (EGF) receptor. Phosphopeptide detection efficiency was significantly improved by using the tyrosine phosphatase inhibitor sodium p...

  16. Interleukin-6 infusion during human endotoxaemia inhibits in vitro release of the urokinase receptor from peripheral blood mononuclear cells

    DEFF Research Database (Denmark)

    Ostrowski, S R; Plomgaard, P; Fischer, C P

    2005-01-01

    Leucocyte expression of the urokinase receptor [urokinase-type plasminogen activator receptor (uPAR)] is regulated by inflammatory mediators. This study investigated the in vivo effect of endotoxin, interleukin (IL)-6 and tumour necrosis factor (TNF)-alpha on uPAR-release in vivo and in vitro in ...

  17. The upregulation of receptor activator NF-kappaB ligand expression by interleukin-1alpha and Porphyromonas endodontalis in human osteoblastic cells.

    Science.gov (United States)

    Chen, S-C; Huang, F-M; Lee, S-S; Li, M-Z; Chang, Y-C

    2009-04-01

    To investigate the receptor activator of nuclear factor-kappa B (NF-kappaB) ligand (RANKL) in osteoblastic cells stimulated with inflammatory mediators. The expression of RANKL in human osteoblastic cell line U2OS stimulated by pro-inflammatory cytokine interleukin (IL)-1alpha and black-pigmented bacteria Porphyromonas endodontalis was investigated by Western blot and enzyme-linked immunosorbent assay (ELISA). The significance of the results obtained from control and treated groups was statistically analysed by the paired Student's t-test. IL-1alpha was found to upregulate RANKL production in U2OS cells (P endodontalis also increased RANKL expression in U2OS cells after 4-h incubation period demonstrated by Western blot and ELISA (P endodontalis may be involved in developing apical periodontitis through the stimulation of RANKL production.

  18. Increased cortisol responsivity to adrenocorticotropic hormone and low plasma levels of interleukin-1 receptor antagonist in women with functional hypothalamic amenorrhea.

    Science.gov (United States)

    Lindahl, Magnus S; Olovsson, Matts; Nyberg, Sigrid; Thorsen, Kim; Olsson, Tommy; Sundström Poromaa, Inger

    2007-01-01

    To assess the hypothalamic-pituitary-adrenal (HPA) axis at all levels, to determine the origin of the previously reported hypercortisolism in patients with functional hypothalamic amenorrhea. A secondary aim was to evaluate factors outside the central nervous system which are known to affect the HPA axis, i.e., circulating levels of interleukin-6 (IL-6), interleukin-1 receptor antagonist (IL-1Ra), and fat mass-adjusted leptin levels, in patients with functional hypothalamic amenorrhea and healthy controls. Cross-sectional study. Umeå University Hospital, Umeå, Sweden. Fifteen subjects with hypothalamic amenorrhea, and 14 age- and weight-matched controls. None. We collected blood samples four times during a 24-hour interval for analysis of cortisol, leptin, IL-1Ra, and IL-6 levels. We performed a low-dose oral dexamethasone test and a low-dose ACTH test. We measured body-fat percentage using a dual-energy X-ray absorptiometer. Patients with hypothalamic amenorrhea had increased diurnal cortisol levels (P<.001). The cortisol response to intravenous low-dose ACTH was increased in functional hypothalamic amenorrhea patients compared to control subjects (P<.01), but they had similar rates of dexamethasone suppression. Patients with hypothalamic amenorrhea also had decreased diurnal leptin (P<.05), and decreased diurnal IL-1Ra levels (P<.05), compared to controls. Body-fat percentage was the main predictor of leptin levels. The present study suggests novel links for the development of functional hypothalamic amenorrhea, including increased adrenal responsiveness and impairments in proinflammatory cytokine pathways.

  19. Hyperosmotic stress inhibits insulin receptor substrate-1 function by distinct mechanisms in 3T3-L1 adipocytes

    DEFF Research Database (Denmark)

    Gual, Philippe; Gonzalez, Teresa; Grémeaux, Thierry

    2003-01-01

    . Furthermore, the mammalian target of rapamycin (mTOR) inhibitor rapamycin prevented the osmotic shock-induced phosphorylation of IRS-1 on Ser307. The inhibition of mTOR completely reversed the inhibitory effect of hyperosmotic stress on insulin-induced IRS-1 tyrosine phosphorylation and PI 3-kinase activation......In 3T3-L1 adipocytes, hyperosmotic stress was found to inhibit insulin signaling, leading to an insulin-resistant state. We show here that, despite normal activation of insulin receptor, hyperosmotic stress inhibits both tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1) and IRS-1....... In addition, prolonged osmotic stress enhanced the degradation of IRS proteins through a rapamycin-insensitive pathway and a proteasome-independent process. These data support evidence of new mechanisms involved in osmotic stress-induced cellular insulin resistance. Short-term osmotic stress induces...

  20. Modern and Convensional Wound Dressing to Interleukin 1 and Interleukin 6 in Diabetic wound

    Directory of Open Access Journals (Sweden)

    Werna Nontji

    2015-04-01

    Full Text Available Introduction:Holistic wound care is one of the ways to prevent gangrene and amputation, modern wound dressing is more effective than convensional with increasing transforming growth factor and cytokine, especially interleukin. This study aims to identify the effectiveness of Modern and Convensional Wound Dressing to Interleukin 1 (IL-1 and Interleukin 6 (IL-6 in Diabetic wound. Method:A Quasi eksperimental pre-post with control group design was used. The intervention given was modern wound dressing and Control group by convensional wound dressing, This study was conducted in Makassar with 32 samples (16 in intervention group and 16 in control group. Result: The result of Pooled T- test showed that p = 0.00 (p < 0.05, it means that there was signifi cant correlation between modern wound dressing to IL-6 and IL-1 than Convensional wound dressing. Discussion: Process of wound healing was produced growth factor and cytokine (IL-1 and IL-6, it will stimulated by wound dressing, modern wound dressing (Calcium alginat can absorb wound drainage, non oklusive, non adhesif, and autolytic debridement. Keywords: Modern wound dressing, Interleukin 1 (IL-1, Interleukin 6 (IL-6

  1. Association between genetic polymorphisms in the human interleukin-7 receptor alpha-chain and inhalation allergy

    DEFF Research Database (Denmark)

    Shamim, Z; Müller, K; Svejgaard, A

    2007-01-01

    Thymic stromal-derived lymphopoietin (TSLP) and interleukin-7 share a common receptor chain, IL-7Ralpha. IL-7 is involved in T-cell homeostasis, and TSLP induces production of pro-allergic cytokines. The gene encoding the IL-7Ralpha chain is polymorphic, and investigation of inhalation allergic p...

  2. Cerebrospinal fluid markers of neuroinflammation in delirium: a role for interleukin-1β in delirium after hip fracture

    NARCIS (Netherlands)

    Cape, Eleanor; Hall, Roanna J.; van Munster, Barbara C.; de Vries, Annick; Howie, Sarah E. M.; Pearson, Andrew; Middleton, Scott D.; Gillies, Fiona; Armstrong, Ian R.; White, Tim O.; Cunningham, Colm; de Rooij, Sophia E.; Maclullich, Alasdair M. J.

    2014-01-01

    Exaggerated central nervous system (CNS) inflammatory responses to peripheral stressors may be implicated in delirium. This study hypothesised that the IL-1β family is involved in delirium, predicting increased levels of interleukin-1β (IL-1β) and decreased IL-1 receptor antagonist (IL-1ra) in the

  3. Resistance to EGF receptor inhibitors in glioblastoma mediated by phosphorylation of the PTEN tumor suppressor at tyrosine 240.

    Science.gov (United States)

    Fenton, Tim R; Nathanson, David; Ponte de Albuquerque, Claudio; Kuga, Daisuke; Iwanami, Akio; Dang, Julie; Yang, Huijun; Tanaka, Kazuhiro; Oba-Shinjo, Sueli Mieko; Uno, Miyuki; Inda, Maria del Mar; Wykosky, Jill; Bachoo, Robert M; James, C David; DePinho, Ronald A; Vandenberg, Scott R; Zhou, Huilin; Marie, Suely K N; Mischel, Paul S; Cavenee, Webster K; Furnari, Frank B

    2012-08-28

    Glioblastoma multiforme (GBM) is the most aggressive of the astrocytic malignancies and the most common intracranial tumor in adults. Although the epidermal growth factor receptor (EGFR) is overexpressed and/or mutated in at least 50% of GBM cases and is required for tumor maintenance in animal models, EGFR inhibitors have thus far failed to deliver significant responses in GBM patients. One inherent resistance mechanism in GBM is the coactivation of multiple receptor tyrosine kinases, which generates redundancy in activation of phosphoinositide-3'-kinase (PI3K) signaling. Here we demonstrate that the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) tumor suppressor is frequently phosphorylated at a conserved tyrosine residue, Y240, in GBM clinical samples. Phosphorylation of Y240 is associated with shortened overall survival and resistance to EGFR inhibitor therapy in GBM patients and plays an active role in mediating resistance to EGFR inhibition in vitro. Y240 phosphorylation can be mediated by both fibroblast growth factor receptors and SRC family kinases (SFKs) but does not affect the ability of PTEN to antagonize PI3K signaling. These findings show that, in addition to genetic loss and mutation of PTEN, its modulation by tyrosine phosphorylation has important implications for the development and treatment of GBM.

  4. Src kinase regulation by phosphorylation and dephosphorylation

    International Nuclear Information System (INIS)

    Roskoski, Robert

    2005-01-01

    Src and Src-family protein-tyrosine kinases are regulatory proteins that play key roles in cell differentiation, motility, proliferation, and survival. The initially described phosphorylation sites of Src include an activating phosphotyrosine 416 that results from autophosphorylation, and an inhibiting phosphotyrosine 527 that results from phosphorylation by C-terminal Src kinase (Csk) and Csk homologous kinase. Dephosphorylation of phosphotyrosine 527 increases Src kinase activity. Candidate phosphotyrosine 527 phosphatases include cytoplasmic PTP1B, Shp1 and Shp2, and transmembrane enzymes include CD45, PTPα, PTPε, and PTPλ. Dephosphorylation of phosphotyrosine 416 decreases Src kinase activity. Thus far PTP-BL, the mouse homologue of human PTP-BAS, has been shown to dephosphorylate phosphotyrosine 416 in a regulatory fashion. The platelet-derived growth factor receptor protein-tyrosine kinase mediates the phosphorylation of Src Tyr138; this phosphorylation has no direct effect on Src kinase activity. The platelet-derived growth factor receptor and the ErbB2/HER2 growth factor receptor protein-tyrosine kinases mediate the phosphorylation of Src Tyr213 and activation of Src kinase activity. Src kinase is also a substrate for protein-serine/threonine kinases including protein kinase C (Ser12), protein kinase A (Ser17), and CDK1/cdc2 (Thr34, Thr46, and Ser72). Of the three protein-serine/threonine kinases, only phosphorylation by CDK1/cdc2 has been demonstrated to increase Src kinase activity. Although considerable information on the phosphoprotein phosphatases that catalyze the hydrolysis of Src phosphotyrosine 527 is at hand, the nature of the phosphatases that mediate the hydrolysis of phosphotyrosine 138 and 213, and phosphoserine and phosphothreonine residues has not been determined

  5. Phosphorylation of the dimeric cytoplasmic domain of the phytosulfokine receptor, PSKR1

    CSIR Research Space (South Africa)

    Muleya, V

    2016-10-01

    Full Text Available Phytosulfokines (PSKs) are plant peptide hormones that co-regulate plant growth, differentiation and defense responses. PSKs signal through a plasma membrane localized leucine-rich repeat receptor-like kinase (phytosulfokine receptor 1, PSKR1...

  6. A1 adenosine receptor-induced phosphorylation and modulation of transglutaminase 2 activity in H9c2 cells: A role in cell survival.

    Science.gov (United States)

    Vyas, Falguni S; Hargreaves, Alan J; Bonner, Philip L R; Boocock, David J; Coveney, Clare; Dickenson, John M

    2016-05-01

    The regulation of tissue transglutaminase (TG2) activity by the GPCR family is poorly understood. In this study, we investigated the modulation of TG2 activity by the A1 adenosine receptor in cardiomyocyte-like H9c2 cells. H9c2 cells were lysed following stimulation with the A1 adenosine receptor agonist N(6)-cyclopentyladenosine (CPA). Transglutaminase activity was determined using an amine incorporating and a protein cross linking assay. TG2 phosphorylation was assessed via immunoprecipitation and Western blotting. The role of TG2 in A1 adenosine receptor-induced cytoprotection was investigated by monitoring hypoxia-induced cell death. CPA induced time and concentration-dependent increases in amine incorporating and protein crosslinking activity of TG2. CPA-induced increases in TG2 activity were attenuated by the TG2 inhibitors Z-DON and R283. Responses to CPA were blocked by PKC (Ro 31-8220), MEK1/2 (PD 98059), p38 MAPK (SB 203580) and JNK1/2 (SP 600125) inhibitors and by removal of extracellular Ca(2+). CPA triggered robust increases in the levels of TG2-associated phosphoserine and phosphothreonine, which were attenuated by PKC, MEK1/2 and JNK1/2 inhibitors. Fluorescence microscopy revealed TG2-mediated biotin-X-cadaverine incorporation into proteins and proteomic analysis identified known (Histone H4) and novel (Hexokinase 1) protein substrates for TG2. CPA pre-treatment reversed hypoxia-induced LDH release and decreases in MTT reduction. TG2 inhibitors R283 and Z-DON attenuated A1 adenosine receptor-induced cytoprotection. TG2 activity was stimulated by the A1 adenosine receptor in H9c2 cells via a multi protein kinase dependent pathway. These results suggest a role for TG2 in A1 adenosine receptor-induced cytoprotection. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Signaling Properties of Chemerin Receptors CMKLR1, GPR1 and CCRL2.

    Science.gov (United States)

    De Henau, Olivier; Degroot, Gaetan-Nagim; Imbault, Virginie; Robert, Virginie; De Poorter, Cédric; Mcheik, Saria; Galés, Céline; Parmentier, Marc; Springael, Jean-Yves

    2016-01-01

    Chemerin is a small chemotactic protein originally identified as the natural ligand of CMKLR1. More recently, two other receptors, GPR1 and CCRL2, have been reported to bind chemerin but their functional relevance remains poorly understood. In this study, we compared the binding and signaling properties of the three human chemerin receptors and showed differences in mode of chemerin binding and receptor signaling. Chemerin binds to all three receptors with low nanomolar affinities. However, the contribution of the chemerin C-terminus to binding efficiency varies greatly amongst receptors. By using BRET-based biosensors monitoring the activation of various G proteins, we showed that binding of chemerin and the chemerin 9 nonapeptide (149YFPGQFAFS157) to CMKLR1 activates the three Gαi subtypes (Gαi1, Gαi2 and Gαi3) and the two Gαo isoforms (Gαoa and Gαob) with potencies correlated to binding affinities. In contrast, no significant activation of G proteins was detected upon binding of chemerin to GPR1 or CCRL2. Binding of chemerin and the chemerin 9 peptide also induced the recruitment of β-arrestin1 and 2 to CMKLR1 and GPR1, though to various degree, but not to CCRL2. However, the propensity of chemerin 9 to activate β-arrestins relative to chemerin is higher when bound to GPR1. Finally, we showed that binding of chemerin to CMKLR1 and GPR1 promotes also the internalization of the two receptors and the phosphorylation of ERK1/2 MAP kinases, although with a different efficiency, and that phosphorylation of ERK1/2 requires both Gαi/o and β-arrestin2 activation but not β-arrestin1. Collectively, these data support a model in which each chemerin receptor displays selective signaling properties.

  8. Integrating TRPV1 Receptor Function with Capsaicin Psychophysics

    Directory of Open Access Journals (Sweden)

    Gregory Smutzer

    2016-01-01

    Full Text Available Capsaicin is a naturally occurring vanilloid that causes a hot, pungent sensation in the human oral cavity. This trigeminal stimulus activates TRPV1 receptors and stimulates an influx of cations into sensory cells. TRPV1 receptors function as homotetramers that also respond to heat, proinflammatory substances, lipoxygenase products, resiniferatoxin, endocannabinoids, protons, and peptide toxins. Kinase-mediated phosphorylation of TRPV1 leads to increased sensitivity to both chemical and thermal stimuli. In contrast, desensitization occurs via a calcium-dependent mechanism that results in receptor dephosphorylation. Human psychophysical studies have shown that capsaicin is detected at nanomole amounts and causes desensitization in the oral cavity. Psychophysical studies further indicate that desensitization can be temporarily reversed in the oral cavity if stimulation with capsaicin is resumed at short interstimulus intervals. Pretreatment of lingual epithelium with capsaicin modulates the perception of several primary taste qualities. Also, sweet taste stimuli may decrease the intensity of capsaicin perception in the oral cavity. In addition, capsaicin perception and hedonic responses may be modified by diet. Psychophysical studies with capsaicin are consistent with recent findings that have identified TRPV1 channel modulation by phosphorylation and interactions with membrane inositol phospholipids. Future studies will further clarify the importance of capsaicin and its receptor in human health and nutrition.

  9. Odor preference learning and memory modify GluA1 phosphorylation and GluA1 distribution in the neonate rat olfactory bulb: testing the AMPA receptor hypothesis in an appetitive learning model.

    Science.gov (United States)

    Cui, Wen; Darby-King, Andrea; Grimes, Matthew T; Howland, John G; Wang, Yu Tian; McLean, John H; Harley, Carolyn W

    2011-01-01

    An increase in synaptic AMPA receptors is hypothesized to mediate learning and memory. AMPA receptor increases have been reported in aversive learning models, although it is not clear if they are seen with memory maintenance. Here we examine AMPA receptor changes in a cAMP/PKA/CREB-dependent appetitive learning model: odor preference learning in the neonate rat. Rat pups were given a single pairing of peppermint and 2 mg/kg isoproterenol, which produces a 24-h, but not a 48-h, peppermint preference in the 7-d-old rat pup. GluA1 PKA-dependent phosphorylation peaked 10 min after the 10-min training trial and returned to baseline within 90 min. At 24 h, GluA1 subunits did not change overall but were significantly increased in synaptoneurosomes, consistent with increased membrane insertion. Immunohistochemistry revealed a significant increase in GluA1 subunits in olfactory bulb glomeruli, the targets of olfactory nerve axons. Glomerular increases were seen at 3 and 24 h after odor exposure in trained pups, but not in control pups. GluA1 increases were not seen as early as 10 min after training and were no longer observed 48 h after training when odor preference is no longer expressed behaviorally. Thus, the pattern of increased GluA1 membrane expression closely follows the memory timeline. Further, blocking GluA1 insertion using an interference peptide derived from the carboxyl tail of the GluA1 subunit inhibited 24 h odor preference memory providing causative support for our hypothesis. PKA-mediated GluA1 phosphorylation and later GluA1 insertion could, conjointly, provide increased AMPA function to support both short-term and long-term appetitive memory.

  10. Determination of HER2 phosphorylation at tyrosine 1221/1222 improves prediction of poor survival for breast cancer patients with hormone receptor-positive tumors

    DEFF Research Database (Denmark)

    Frogne, Thomas; Laenkholm, Anne-Vibeke; Lyng, Maria B

    2009-01-01

    INTRODUCTION: High expression of total HER2 protein confers poor prognosis for breast cancer patients. HER2 is a member of the HER family consisting of four receptors, HER1 to HER4. HER receptor activity is regulated by a variety of mechanisms, and phosphorylation of the C-terminal part of the HER...... metastases, by evaluating the expression of phosphorylated HER1, HER2, HER3, Erk, Akt and the total level of HER4 and HER2. METHODS: Immunohistochemical analysis was performed on 268 primary breast tumors and 30 paired metastatic lesions from postmenopausal women with hormone receptor-positive breast tumors...... of Akt and Erk were quite uniformly expressed in the categories; negative, moderate or strong. In univariate analysis, expression of total HER2, pHER1, pHER2 and pHER3 was significantly associated with poor disease-free survival. Strong HER4 expression was associated with prolonged disease-free as well...

  11. Follicle-stimulating hormone (FSH) activates extracellular signal-regulated kinase phosphorylation independently of beta-arrestin- and dynamin-mediated FSH receptor internalization

    Science.gov (United States)

    Piketty, Vincent; Kara, Elodie; Guillou, Florian; Reiter, Eric; Crepieux, Pascale

    2006-01-01

    Background The follicle-stimulating hormone receptor (FSH-R) is a seven transmembrane spanning receptor (7TMR) which plays a crucial role in male and female reproduction. Upon FSH stimulation, the FSH-R activates the extracellular signal-regulated kinases (ERK). However, the mechanisms whereby the agonist-stimulated FSH-R activates ERK are poorly understood. In order to activate ERK, some 7 TMRs require beta-arrestin-and dynamin-dependent internalization to occur, whereas some others do not. In the present study, we examined the ability of the FSH-activated FSH-R to induce ERK phosphorylation, in conditions where its beta-arrestin- and dynamin-mediated internalization was impaired. Methods Human embryonic kidney (HEK) 293 cells were transiently transfected with the rat FSH-R. Internalization of the FSH-R was manipulated by co-expression of either a beta-arrestin (319–418) dominant negative peptide, either an inactive dynamin K44A mutant or of wild-type beta-arrestin 1 or 2. The outcomes on the FSH-R internalization were assayed by measuring 125I-FSH binding at the cell surface when compared to internalized 125I-FSH binding. The resulting ERK phosphorylation level was visualized by Western blot analysis. Results In HEK 293 cells, FSH stimulated ERK phosphorylation in a dose-dependent manner. Co-transfection of the beta- arrestin (319–418) construct, or of the dynamin K44A mutant reduced FSH-R internalization in response to FSH, without affecting ERK phosphorylation. Likewise, overexpression of wild-type beta-arrestin 1 or 2 significantly increased the FSH-R internalization level in response to FSH, without altering FSH-induced ERK phosphorylation. Conclusion From these results, we conclude that the FSH-R does not require beta-arrestin- nor dynamin-mediated internalization to initiate ERK phosphorylation in response to FSH. PMID:16787538

  12. Increased Eps15 homology domain 1 and RAB11FIP3 expression regulate breast cancer progression via promoting epithelial growth factor receptor recycling.

    Science.gov (United States)

    Tong, Dandan; Liang, Ya-Nan; Stepanova, A A; Liu, Yu; Li, Xiaobo; Wang, Letian; Zhang, Fengmin; Vasilyeva, N V

    2017-02-01

    Recent research indicates that the C-terminal Eps15 homology domain 1 is associated with epithelial growth factor receptor-mediated endocytosis recycling in non-small-cell lung cancer. The aim of this study was to determine the clinical significance of Eps15 homology domain 1 gene expression in relation to phosphorylation of epithelial growth factor receptor expression in patients with breast cancer. Primary breast cancer samples from 306 patients were analyzed for Eps15 homology domain 1, RAB11FIP3, and phosphorylation of epithelial growth factor receptor expression via immunohistochemistry. The clinical significance was assessed via a multivariate Cox regression analysis, Kaplan-Meier curves, and the log-rank test. Eps15 homology domain 1 and phosphorylation of epithelial growth factor receptor were upregulated in 60.46% (185/306) and 53.92% (165/306) of tumor tissues, respectively, as assessed by immunohistochemistry. The statistical correlation analysis indicated that Eps15 homology domain 1 overexpression was positively correlated with the increases in phosphorylation of epithelial growth factor receptor ( r = 0.242, p breast cancer for the overall survival in the total, chemotherapy, and human epidermal growth factor receptor 2 (-) groups. However, the use of combined expression of Eps15 homology domain 1 and phosphorylation of epithelial growth factor receptor markers is more effective for the disease-free survival in the overall population, chemotherapy, and human epidermal growth factor receptor 2 (-) groups. Moreover, the combined markers are also significant prognostic markers of breast cancer in the human epidermal growth factor receptor 2 (+), estrogen receptor (+), and estrogen receptor (-) groups. Eps15 homology domain 1 has a tumor suppressor function, and the combined marker of Eps15 homology domain 1/phosphorylation of epithelial growth factor receptor expression was identified as a better prognostic marker in breast cancer diagnosis

  13. Agonistic effects of a monoclonal antibody specific for the interleukin-2 receptor

    International Nuclear Information System (INIS)

    Eardley, D.D.; Makrides, V.

    1986-01-01

    Interleukin-2 (IL-2) mediated immune responses can be blocked by monoclonal antibodies to the IL-2 receptor. The monoclonal antibody, M720, is defined as specific for the IL-2 receptor because it blocks 35 S-IL-2 binding to Con A blasts, reacts with lymphoblasts but not resting splenocytes, and inhibits IL-2 induced proliferation to mitogen, antigen, or allogeneic stimuli. Under appropriate culture conditions, the IL-2 receptor-specific antibody can act like IL-2 in that it will induce proliferation in T cells in the absence of additional antigen or mitogen. This agonistic effect is dependent on time, dose of antibody, and requires fetal calf serum (FCS) in the media. Because the FCS is not mitogenic by itself, the authors propose that the FCS components act as incomplete mitogen to induce appearance of IL-2 receptors but lack a factor which would push the majority of the cells into the S phase of the cell cycle. This factor is usually IL-2, but in the authors experiments, the IL-2 receptor-specific antibody can provide the same stimulus. These data indicate that factors like FCS can induce IL-2 receptors, but without additional IL-2 or receptor triggering, the cells will not proceed through the synthetic and proliferative phases of cell growth

  14. Interleukin 1 is an autocrine regulator of human endothelial cell growth

    International Nuclear Information System (INIS)

    Cozzolino, F.; Torcia, M.; Aldinucci, D.; Ziche, M.; Bani, D.; Almerigogna, F.; Stern, D.M.

    1990-01-01

    Proliferation of endothelial cells is regulated through the autocrine production of growth factors and the expression of cognate surface receptors. In this study, the authors demonstrate that interleukin 1 (IL-1) is an inhibitor of endothelial growth in vitro and in vivo. IL-1 arrested growing, cultured endothelial cells in G 1 phase; inhibition of proliferation was dose dependent and occurred in parallel with occupancy of endothelial surface IL-1 receptors. In an angiogenesis model, IL-1 could inhibit fibroblast growth factor-induced vessel formation. The autocrine nature of the IL-1 effect on endothelial proliferation was demonstrated by the observation that occupancy of cell-surface receptors by endogenous IL-1 depressed cell growth. The potential significance of this finding was emphasized by the detection of IL-1 in the native endothelium of human umbilical veins. A mechanism by which IL-1 may exert its inhibitory effect on endothelial cell growth was suggested by studies showing that IL-1 decreased the expression of high-affinity fibroblast growth factor binding sites on endothelium. These results point to a potentially important role of IL-1 in regulating blood vessel growth the suggest that autocrine production of inhibitory factors may be a mechanism controlling proliferation of normal cells

  15. Expression of an insulin/interleukin-1 receptor antagonist hybrid gene in insulin-producing cell lines (HIT-T15 and NIT-1) confers resistance against interleukin-1-induced nitric oxide production.

    Science.gov (United States)

    Welsh, N; Bendtzen, K; Welsh, M

    1995-01-01

    A hybrid gene consisting of the insulin gene enhancer/promoter region, the signal sequence, the insulin B- and C-chains, and the human interleukin-1 receptor antagonist (IL-1ra) gene was constructed. This hybrid gene was transfected together with the pSV2-neo construct into the insulin-producing cell lines HIT-T15 and NIT-1. One of the geneticin-selected clones, HITra2, expressed a 1.4-kb mRNA, which hybridized both to insulin and IL-1ra-cDNA in Northern blot analysis. Three proteins, with the mol wt 23, 17, and 14 kD, were immunoprecipitated with anti-IL-1ra antibodies from [35S]methionine-labeled HITra2 cells. Both at a low and at a high glucose concentration, 4-5 ng of IL-1ra/10(6) cells (ELISA) was released from these cells. On the other hand, a high glucose concentration evoked a three-fold increase in the release of insulin, suggesting that IL-1ra was released constitutively. Measured by nitrite production, transfected HIT, and NIT-1 cells exhibited a more than 10-fold decrease in IL-1 beta sensitivity. Since the conditioned culture media from the HITra2 cells exhibited an anti-IL-1 beta activity of only 0.5 U/ml, and mixed culture of HITra2 cells and isolated rat islets prevented IL-1 beta induced inhibition of insulin release, it is likely that IL-1ra acts locally at the cell surface. It is concluded that expression of a hybrid insulin/IL-1ra gene confers resistance to IL-1 and that this technique may be used to elucidate the role of IL-1 in autoimmune disorders such as insulin-dependent diabetes mellitus. Images PMID:7706480

  16. ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, Junko; Takahashi, Katsuyuki; Ogawa, Hiroko; Asano, Keiichi; Faruk Hatipoglu, Omer; Zeynel Cilek, Mehmet; Obika, Masanari; Ohtsuki, Takashi [Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama (Japan); Hofmann, Matthias [Department of Dermatology, Venereology and Allergology, Goethe University, Frankfurt (Germany); Kusachi, Shozo [Department of Medical Technology, Okayama University Graduate School of Health Sciences, Okayama (Japan); Ninomiya, Yoshifumi [Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama (Japan); Hirohata, Satoshi, E-mail: hirohas@cc.okayama-u.ac.jp [Department of Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama (Japan); International Center, Okayama University, Okayama (Japan)

    2014-05-01

    Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy. - Highlights: • ADAMTS1 significantly inhibited tube formation and cell proliferation in HMVEC-dLy. • Reduced lymph endothelial cell migration in ADAMTS1 transduced co-culture systems. • VEGFC-stimulated phosphorylation of VEGFR3 is attenuated by ADAMTS1. • Reduced phosphorylation of Akt and ERK1/2 in ADAMTS1 treated HMVEC-dLy. • ADAMTS1 binds directly to VEGFC.

  17. ADAMTS1 inhibits lymphangiogenesis by attenuating phosphorylation of the lymphatic endothelial cell-specific VEGF receptor

    International Nuclear Information System (INIS)

    Inagaki, Junko; Takahashi, Katsuyuki; Ogawa, Hiroko; Asano, Keiichi; Faruk Hatipoglu, Omer; Zeynel Cilek, Mehmet; Obika, Masanari; Ohtsuki, Takashi; Hofmann, Matthias; Kusachi, Shozo; Ninomiya, Yoshifumi; Hirohata, Satoshi

    2014-01-01

    Angiogenesis and lymphangiogenesis play roles in malignant tumor progression, dissemination, and metastasis. ADAMTS1, a member of the matrix metalloproteinase family, is known to inhibit angiogenesis. Recombinant ADAMTS1 was shown to strongly inhibit angiogenesis. We investigated whether ADAMTS1 inhibited lymphangiogenesis in the present study. We examined cell proliferation and cell migration in normal human dermal lymphatic microvascular endothelial cells (HMVEC-dLy) transduced with or without adenoviral human ADAMTS1 gene therapy. We then examined the VEGFC/VEGFR3 signal transduction pathway in ADAMTS1-transduced HMVEC-dLy. Cell proliferation and tube formation in Matrigel were significantly lower with transduced ADAMTS1 than with control (non-transduced HMVEC-dLy). The phosphorylation of VEGFR3 was also attenuated by ADAMTS1 gene therapy in HMVEC-dLy. Immunoprecipitation assays revealed that ADAMTS1 formed a complex with VEGFC. Our results demonstrated that ADAMTS1 inhibited lymphangiogenesis in vitro. The data highlight the new function of ADAMTS1 in the regulation of lymphangiogenesis and the therapeutic potential of ADAMTS1 in cancer therapy. - Highlights: • ADAMTS1 significantly inhibited tube formation and cell proliferation in HMVEC-dLy. • Reduced lymph endothelial cell migration in ADAMTS1 transduced co-culture systems. • VEGFC-stimulated phosphorylation of VEGFR3 is attenuated by ADAMTS1. • Reduced phosphorylation of Akt and ERK1/2 in ADAMTS1 treated HMVEC-dLy. • ADAMTS1 binds directly to VEGFC

  18. Interleukins in preeclampsia

    International Nuclear Information System (INIS)

    Olusi, Samuel O.; Diejomahoh, M.; Omu, A.; Abdulaziz, A.; Prabha, K.; George, S.

    2000-01-01

    Preeclampsia is a multisystemic disorder of unknown etiology. Recently,endothelial damage has been implicated in its cause. The objective of thisstudy was to determine the role of interleukins in the etiology ofpreeclampsia. 32 primigravidas with preeclampsia but without any clinicalevidence of infection and 32 age-matched primigravidas with uncomplicatednormal pregnancies were investigated. Phlebotomy was performed at 32 weeks ofgestation and blood collected for immunoassay of interleukin-2 (IL-2),interleukin-2 receptor (IL-2R), interleukin-6 (IL-6), interleukin-8 (IL-8)andvinterleukin-10 (IL-10), using commercially available immunoassay kits.Although the maternal plasma concentrations of IL-2 and IL-2R were slightlyhigher in normal pregnant women (76.3+-13.7 pg/mL and 526+-47.1pg/mL,respectively) than in women with preeclampsia (57.8+-1.08 pg/mL and476.9+-3.9pg/mL, respectively), the difference was not statistically significant(P>0.05). However, maternal plasma IL-6 and IL-8 concentrations weresignificantly higher (P<0.05) in normal pregnancy (158.0+-35.4 pg/mL and5163.6+- 800pg/mL, respectively) than in pregnancy complicated withpreeclampsia (60.0+-13.7 pg/mL and 2495.8+-729 pg/mL, respectively). On thepther hand, maternal plasma concentration of IL-10 was significantly higher(P<0.05) in preeclampsia (93.2+-24.1 pg/mL) than in normal pregnancy(31.0+-7.0 pg/mL). It is concluded that the elevated maternal plasma IL-10concentration in preeclampsia may be protective response to maternalimmunorejection. (author)

  19. PICK1 interacts with ABP/GRIP to regulate AMPA receptor trafficking.

    Science.gov (United States)

    Lu, Wei; Ziff, Edward B

    2005-08-04

    PICK1 and ABP/GRIP bind to the AMPA receptor (AMPAR) GluR2 subunit C terminus. Transfer of the receptor from ABP/GRIP to PICK1, facilitated by GluR2 S880 phosphorylation, may initiate receptor trafficking. Here we report protein interactions that regulate these steps. The PICK1 BAR domain interacts intermolecularly with the ABP/GRIP linker II region and intramolecularly with the PICK1 PDZ domain. Binding of PKCalpha or GluR2 to the PICK1 PDZ domain disrupts the intramolecular interaction and facilitates the PICK1 BAR domain association with ABP/GRIP. Interference with the PICK1-ABP/GRIP interaction impairs S880 phosphorylation of GluR2 by PKC and decreases the constitutive surface expression of GluR2, the NMDA-induced endocytosis of GluR2, and recycling of internalized GluR2. We suggest that the PICK1 interaction with ABP/GRIP is a critical step in controlling GluR2 trafficking.

  20. Insulin-Mimetic Action of Rhoifolin and Cosmosiin Isolated from Citrus grandis (L. Osbeck Leaves: Enhanced Adiponectin Secretion and Insulin Receptor Phosphorylation in 3T3-L1 Cells

    Directory of Open Access Journals (Sweden)

    Yerra Koteswara Rao

    2011-01-01

    Full Text Available Citrus grandis (L. Osbeck (red wendun leaves have been used in traditional Chinese medicine to treat several illnesses including diabetes. However, there is no scientific evidence supporting these actions and its active compounds. Two flavone glycosides, rhoifolin and cosmosiin were isolated for the first time from red wendun leaves and, identified these leaves are rich source for rhoifolin (1.1%, w/w. In differentiated 3T3-L1 adipocytes, rhoifolin and cosmosiin showed dose-dependent response in concentration range of o.oo1–5 μM and 1–20 μM, respectively, in biological studies beneficial to diabetes. Particularly, rhoifolin and cosmosiin at 0.5 and 20 μM, respectively showed nearly similar response to that 10 nM of insulin, on adiponectin secretion level. Furthermore, 5 μM of rhoifolin and 20 μM of cosmosiin showed equal potential with 10 nM of insulin to increase the phosphorylation of insulin receptor-β, in addition to their positive effect on GLUT4 translocation. These findings indicate that rhoifolin and cosmosiin from red wendun leaves may be beneficial for diabetic complications through their enhanced adiponectin secretion, tyrosine phosphorylation of insulin receptor-β and GLUT4 translocation.

  1. Genetic polymorphism of interleukin-1A (IL-1A), IL-1B, and IL-1 receptor antagonist (IL-1RN) and prostate cancer risk.

    Science.gov (United States)

    Xu, Hua; Ding, Qiang; Jiang, Hao-Wen

    2014-01-01

    We aimed to investigate the associations between polymorphisms of interleukin-1A (IL-1A), IL-1B, and IL-1 receptor antagonist (IL-1RN) and prostate cancer (PCa) risk. A comprehensive search for articles of MEDLINE and EMBASE databases and bibliographies of retrieved articles published up to August 3, 2014 was performed. Methodological quality assessment of the trials was based on a standard quality scoring system. The meta-analysis was performed using STATA 12.0. We included 9 studies (1 study for IL-1A, 5 studies for IL-1B, and 3 studies for IL-1RN), and significant association was found between polymorphisms of IL-1B-511 (rs16944) as well as IL-1B-31 (rs1143627) and PCa risk. IL-1B-511 (rs16944) polymorphism was significantly associated with PCa risk in homozygote and recessive models, as well as allele contrast (TT vs CC: OR, 0.74; 95%CI, 0.58-0.94; P=0.012; TT vs TC+CC; OR, 0.79; 95%CI, 0.63-0.98; P=0.033; T vs C: OR, 0.86; 95%CI, 0.77-0.96; P=0.008). The association between IL-1B-31 (rs1143627) polymorphism and PCa risk was weakly significant under a heterozygote model (OR, 1.35; 95%CI, 1.00-1.80; P=0.047). Sequence variants in IL-1B-511 (rs16944) and IL-1B-31 (rs1143627) are significantly associated with PCa risk, which provides additional novel evidence that proinflammatory cytokines and inflammation play an important role in the etiology of PCa.

  2. Discoidin Domain Receptor 1 Mediates Myosin-Dependent Collagen Contraction

    Directory of Open Access Journals (Sweden)

    Nuno M. Coelho

    2017-02-01

    Full Text Available Discoidin domain receptor 1 (DDR1 is a tyrosine kinase collagen adhesion receptor that mediates cell migration through association with non-muscle myosin IIA (NMIIA. Because DDR1 is implicated in cancer fibrosis, we hypothesized that DDR1 interacts with NMIIA to enable collagen compaction by traction forces. Mechanical splinting of rat dermal wounds increased DDR1 expression and collagen alignment. In periodontal ligament of DDR1 knockout mice, collagen mechanical reorganization was reduced >30%. Similarly, cultured cells with DDR1 knockdown or expressing kinase-deficient DDR1d showed 50% reduction of aligned collagen. Tractional remodeling of collagen was dependent on DDR1 clustering, activation, and interaction of the DDR1 C-terminal kinase domain with NMIIA filaments. Collagen remodeling by traction forces, DDR1 tyrosine phosphorylation, and myosin light chain phosphorylation were increased on stiff versus soft substrates. Thus, DDR1 clustering, activation, and interaction with NMIIA filaments enhance the collagen tractional remodeling that is important for collagen compaction in fibrosis.

  3. The O-β-linked N-acetylglucosaminylation of the Lamin B receptor and its impact on DNA binding and phosphorylation.

    Science.gov (United States)

    Smet-Nocca, Caroline; Page, Adeline; Cantrelle, François-Xavier; Nikolakaki, Eleni; Landrieu, Isabelle; Giannakouros, Thomas

    2018-04-01

    Lamin B Receptor (LBR) is an integral protein of the interphase inner nuclear membrane that is implicated in chromatin anchorage to the nuclear envelope. Phosphorylation of a stretch of arginine-serine (RS) dipeptides in the amino-terminal nucleoplasmic domain of LBR regulates the interactions of the receptor with other nuclear proteins, DNA and RNA and thus modulates tethering of heterochromatin to the nuclear envelope. While phosphorylation has been extensively studied, very little is known about other post-translational modifications of the protein. There is only one report on the O-β-linked N-acetyl-glucosaminylation (O-GlcNAcylation) of a serine residue downstream of the RS domain of rat LBR. In the present study we identify additional O-GlcNAcylation sites by using as substrates of O-β-N-acetylglucosaminyltransferase (OGT) a set of peptides containing the entire LBR RS domain or parts of it as well as flanking sequences. The in vitro activity of OGT was assessed by tandem mass spectrometry and NMR spectroscopy. Furthermore, we provide evidence that O-GlcNAcylation hampers DNA binding while it marginally affects RS domain phosphorylation mediated by SRPK1, Akt2 and cdk1 kinases. Our methodology providing a quantitative description of O-GlcNAc patterns based on a combination of mass spectrometry and high resolution NMR spectroscopy on short peptide substrates allows subsequent functional analyses. Hence, our approach is of general interest to a wide audience of biologists aiming at deciphering the functional role of O-GlcNAc glycosylation and its crosstalk with phosphorylation. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Nuclear insulin-like growth factor 1 receptor phosphorylates proliferating cell nuclear antigen and rescues stalled replication forks after DNA damage.

    Science.gov (United States)

    Waraky, Ahmed; Lin, Yingbo; Warsito, Dudi; Haglund, Felix; Aleem, Eiman; Larsson, Olle

    2017-11-03

    We have previously shown that the insulin-like growth factor 1 receptor (IGF-1R) translocates to the cell nucleus, where it binds to enhancer-like regions and increases gene transcription. Further studies have demonstrated that nuclear IGF-1R (nIGF-1R) physically and functionally interacts with some nuclear proteins, i.e. the lymphoid enhancer-binding factor 1 (Lef1), histone H3, and Brahma-related gene-1 proteins. In this study, we identified the proliferating cell nuclear antigen (PCNA) as a nIGF-1R-binding partner. PCNA is a pivotal component of the replication fork machinery and a main regulator of the DNA damage tolerance (DDT) pathway. We found that IGF-1R interacts with and phosphorylates PCNA in human embryonic stem cells and other cell lines. In vitro MS analysis of PCNA co-incubated with the IGF-1R kinase indicated tyrosine residues 60, 133, and 250 in PCNA as IGF-1R targets, and PCNA phosphorylation was followed by mono- and polyubiquitination. Co-immunoprecipitation experiments suggested that these ubiquitination events may be mediated by DDT-dependent E2/E3 ligases ( e.g. RAD18 and SHPRH/HLTF). Absence of IGF-1R or mutation of Tyr-60, Tyr-133, or Tyr-250 in PCNA abrogated its ubiquitination. Unlike in cells expressing IGF-1R, externally induced DNA damage in IGF-1R-negative cells caused G 1 cell cycle arrest and S phase fork stalling. Taken together, our results suggest a role of IGF-1R in DDT. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Phosphorylation sites of Arabidopsis MAP Kinase Substrate 1 (MKS1)

    DEFF Research Database (Denmark)

    Caspersen, M.B.; Qiu, J.-L.; Zhang, X.

    2007-01-01

    The Arabidopsis MAP kinase 4 (MPK4) substrate MKS1 was expressed in Escherichia coli and purified, full-length, 6x histidine (His)-tagged MKS1 was phosphorylated in vitro by hemagglutinin (HA)-tagged MPK4 immuno-precipitated from plants. MKS1 phosphorylation was initially verified by electrophore......The Arabidopsis MAP kinase 4 (MPK4) substrate MKS1 was expressed in Escherichia coli and purified, full-length, 6x histidine (His)-tagged MKS1 was phosphorylated in vitro by hemagglutinin (HA)-tagged MPK4 immuno-precipitated from plants. MKS1 phosphorylation was initially verified...... phosphopeptide detection. As MAP kinases generally phosphorylate serine or threonine followed by proline (Ser/Thr-Pro), theoretical masses of potentially phosphorylated peptides were calculated and mass spectrometric peaks matching these masses were fragmented and searched for a neutral-loss signal...... at approximately 98 Da indicative of phosphorylation. Additionally, mass spectrometric peaks present in the MPK4-treated MKS1, but not in the control peptide map of untreated MKS1, were fragmented. Fragmentation spectra were subjected to a MASCOT database search which identified three of the twelve Ser-Pro serine...

  6. Proteotoxic stress induces phosphorylation of p62/SQSTM1 by ULK1 to regulate selective autophagic clearance of protein aggregates.

    Directory of Open Access Journals (Sweden)

    Junghyun Lim

    Full Text Available Disruption of proteostasis, or protein homeostasis, is often associated with aberrant accumulation of misfolded proteins or protein aggregates. Autophagy offers protection to cells by removing toxic protein aggregates and injured organelles in response to proteotoxic stress. However, the exact mechanism whereby autophagy recognizes and degrades misfolded or aggregated proteins has yet to be elucidated. Mounting evidence demonstrates the selectivity of autophagy, which is mediated through autophagy receptor proteins (e.g. p62/SQSTM1 linking autophagy cargos and autophagosomes. Here we report that proteotoxic stress imposed by the proteasome inhibition or expression of polyglutamine expanded huntingtin (polyQ-Htt induces p62 phosphorylation at its ubiquitin-association (UBA domain that regulates its binding to ubiquitinated proteins. We find that autophagy-related kinase ULK1 phosphorylates p62 at a novel phosphorylation site S409 in UBA domain. Interestingly, phosphorylation of p62 by ULK1 does not occur upon nutrient starvation, in spite of its role in canonical autophagy signaling. ULK1 also phosphorylates S405, while S409 phosphorylation critically regulates S405 phosphorylation. We find that S409 phosphorylation destabilizes the UBA dimer interface, and increases binding affinity of p62 to ubiquitin. Furthermore, lack of S409 phosphorylation causes accumulation of p62, aberrant localization of autophagy proteins and inhibition of the clearance of ubiquitinated proteins or polyQ-Htt. Therefore, our data provide mechanistic insights into the regulation of selective autophagy by ULK1 and p62 upon proteotoxic stress. Our study suggests a potential novel drug target in developing autophagy-based therapeutics for the treatment of proteinopathies including Huntington's disease.

  7. The insulin receptor substrate (IRS)-1 pleckstrin homology domain functions in downstream signaling.

    Science.gov (United States)

    Vainshtein, I; Kovacina, K S; Roth, R A

    2001-03-16

    The pleckstrin homology (PH) domain of the insulin receptor substrate-1 (IRS-1) plays a role in directing this molecule to the insulin receptor, thereby regulating its tyrosine phosphorylation. In this work, the role of the PH domain in subsequent signaling was studied by constructing constitutively active forms of IRS-1 in which the inter-SH2 domain of the p85 subunit of phosphatidylinositol 3-kinase was fused to portions of the IRS-1 molecule. Chimeric molecules containing the PH domain were found to activate the downstream response of stimulating the Ser/Thr kinase Akt. A chimera containing point mutations in the PH domain that abolished the ability of this domain to bind phosphatidylinositol 4,5-bisphosphate prevented these molecules from activating Akt. These mutations also decreased by about 70% the amount of the constructs present in a particulate fraction of the cells. These results indicate that the PH domain of IRS-1, in addition to directing this protein to the receptor for tyrosine phosphorylation, functions in the ability of this molecule to stimulate subsequent responses. Thus, compromising the function of the PH domain, e.g. in insulin-resistant states, could decrease both the ability of IRS-1 to be tyrosine phosphorylated by the insulin receptor and to link to subsequent downstream targets.

  8. IRS-1 serine phosphorylation and insulin resistance in skeletal muscle from pancreas tranplant recipient

    DEFF Research Database (Denmark)

    Bouzakri, K; Karlsson, HRK; Vestergaard, Henrik

    2006-01-01

    Insulin-dependent diabetic recipients of successful pancreas allografts achieve self-regulatory insulin secretion and discontinue exogenous insulin therapy; however, chronic hyperinsulinemia and impaired insulin sensitivity generally develop. To determine whether insulin resistance is accompanied...... by altered signal transduction, skeletal muscle biopsies were obtained from pancreas-kidney transplant recipients (n = 4), nondiabetic kidney transplant recipients (receiving the same immunosuppressive drugs; n = 5), and healthy subjects (n = 6) before and during a euglycemic-hyperinsulinemic clamp. Basal...... insulin receptor substrate (IRS)-1 Ser (312) and Ser (616) phosphorylation, IRS-1-associated phosphatidylinositol 3-kinase activity, and extracellular signal-regulated kinase (ERK)-1/2 phosphorylation were elevated in pancreas-kidney transplant recipients, coincident with fasting hyperinsulinemia. Basal...

  9. IRS-1 serine phosphorylation and insulin resistance in skeletal muscle from pancreas transplant recipients

    DEFF Research Database (Denmark)

    Bouzakri, Karim; Karlsson, Håkan K R; Vestergaard, Henrik

    2006-01-01

    Insulin-dependent diabetic recipients of successful pancreas allografts achieve self-regulatory insulin secretion and discontinue exogenous insulin therapy; however, chronic hyperinsulinemia and impaired insulin sensitivity generally develop. To determine whether insulin resistance is accompanied...... by altered signal transduction, skeletal muscle biopsies were obtained from pancreas-kidney transplant recipients (n = 4), nondiabetic kidney transplant recipients (receiving the same immunosuppressive drugs; n = 5), and healthy subjects (n = 6) before and during a euglycemic-hyperinsulinemic clamp. Basal...... insulin receptor substrate (IRS)-1 Ser (312) and Ser (616) phosphorylation, IRS-1-associated phosphatidylinositol 3-kinase activity, and extracellular signal-regulated kinase (ERK)-1/2 phosphorylation were elevated in pancreas-kidney transplant recipients, coincident with fasting hyperinsulinemia. Basal...

  10. Large-scale meta-analysis of interleukin-1 beta and interleukin-1 receptor antagonist polymorphisms on risk of radiographic hip and knee osteoarthritis and severity of knee osteoarthritis.

    Science.gov (United States)

    Kerkhof, H J M; Doherty, M; Arden, N K; Abramson, S B; Attur, M; Bos, S D; Cooper, C; Dennison, E M; Doherty, S A; Evangelou, E; Hart, D J; Hofman, A; Javaid, K; Kerna, I; Kisand, K; Kloppenburg, M; Krasnokutsky, S; Maciewicz, R A; Meulenbelt, I; Muir, K R; Rivadeneira, F; Samuels, J; Sezgin, M; Slagboom, E; Smith, A J P; Spector, T D; Tamm, A; Tamm, A; Uitterlinden, A G; Wheeler, M; Zhai, G; Zhang, W; van Meurs, J B J; Valdes, A M

    2011-03-01

    To clarify the role of common genetic variation in the Interleukin-1β (IL1B) and Interleukin-1R antagonist (IL1RN) genes on risk of knee and hip osteoarthritis (OA) and severity of knee OA by means of large-scale meta-analyses. We searched PubMed for articles assessing the role of IL1B and IL1RN polymorphisms/haplotypes on the risk of hip and/or knee OA. Novel data were included from eight unpublished studies. Meta-analyses were performed using fixed- and random-effects models with a total of 3595 hip OA and 5013 knee OA cases, and 6559 and 9132 controls respectively. The role of ILRN haplotypes on radiographic severity of knee OA was tested in 1918 cases with Kellgren-Lawrence (K/L) 1 or 2 compared to 199 cases with K/L 3 or 4. The meta-analysis of six published studies retrieved from the literature search and eight unpublished studies showed no evidence of association between common genetic variation in the IL1B or IL1RN genes and risk of hip OA or knee OA (P>0.05 for rs16944, rs1143634, rs419598 and haplotype C-G-C (rs1143634, rs16944 and rs419598) previously implicated in risk of hip OA). The C-T-A haplotype formed by rs419598, rs315952 and rs9005, previously implicated in radiographic severity of knee OA, was associated with reduced severity of knee OA (odds ratio (OR)=0.71 95%CI 0.56-0.91; P=0.006, I(2)=74%), and achieved borderline statistical significance in a random-effects model (OR=0.61 95%CI 0.35-1.06 P=0.08). Common genetic variation in the Interleukin-1 region is not associated with prevalence of hip or knee OA but our data suggest that IL1RN might have a role in severity of knee OA. Copyright © 2010 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  11. The potential role of SOCS-3 in the interleukin-1beta-induced desensitization of insulin signaling in pancreatic beta-cells

    DEFF Research Database (Denmark)

    Emanuelli, Brice; Glondu, Murielle; Filloux, Chantal

    2004-01-01

    insulin signaling is required for the optimal beta-cell function, we assessed the effect of IL-1beta on the insulin pathway in a rat pancreatic beta-cell line. We show that IL-1beta decreases insulin-induced tyrosine phosphorylation of the insulin receptor (IR) and insulin receptor substrate (IRS...

  12. Isoflavones enhance interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

    Science.gov (United States)

    Kojima, Hiroyuki; Takeda, Yukimasa; Muromoto, Ryuta; Takahashi, Miki; Hirao, Toru; Takeuchi, Shinji; Jetten, Anton M.; Matsuda, Tadashi

    2018-01-01

    The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. In this study, we investigated the effects of isoflavones on RORα/γ activity and the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In doxycycline-inducible CHO stable cell lines, we found that four isoflavones, biochanin A (BA), genistein, formononetin, and daidzein, enhanced RORα- or RORγ-mediated transcriptional activity in a dose-dependent manner. In an activation assay of the Il17a promoter using Jurkat cells, these compounds enhanced the RORα- or RORγ-mediated activation of the Il17a promoter at concentrations of 1 × 10−6 M to 1 × 10−5 M. In mammalian two-hybrid assays, the four isoflavones enhanced the interaction between the RORα- or RORγ-ligand binding domain and the co-activator LXXLL peptide in a dose-dependent manner. In addition, these isoflavones potently enhanced Il17a mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin, but showed slight enhancement of Il17a gene expression in RORα/γ-knockdown EL4 cells. Immunoprecipitation and immunoblotting assays also revealed that BA enhanced the interaction between RORγt and SRC-1, which is a co-activator for nuclear receptors. Taken together, these results suggest that the isoflavones have the ability to enhance IL-17 gene expression by stabilizing the interactions between RORα/γ and co-activators. This also provides the first evidence that dietary chemicals can enhance IL-17 gene expression in immune cells. PMID:25583575

  13. Interleukin-8 and Its Receptors in Human Milk from Mothers of Full-Term and Premature Infants.

    Science.gov (United States)

    Polat, Adem; Tunc, Turan; Erdem, Galip; Yerebasmaz, Neslihan; Tas, Ahmet; Beken, Serdar; Basbozkurt, Gokalp; Saldir, Mehmet; Zenciroglu, Aysegul; Yaman, Halil

    2016-06-01

    In addition to its nutritional benefits, human milk also has bioactive elements. Limited immunological functions of newborns are supported and altered by the immunological elements of mother milk. Chemokines are of importance among these immune factors. Interleukin-8 (IL-8) has been demonstrated in mother's milk, and its receptors, CXC chemokine receptors (CXCR)-1 and CXCR-2, were detected on cells, responsible for immunological reactions and mammary glandular cells. The soluble forms of these receptors are yet to be described in human milk. In this study, it was aimed to assess the IL-8 levels and the concentrations of its receptors in colostrum and mature mother's milk in regard to preterm and term delivery. The results of this study indicated a decline in IL-8 levels with the lactation stage, but no difference was observed between term and preterm mother's milk. Regarding the CXCR-1 and CXCR-2, the concentrations of these receptors were similar in both colostrum and mature milk. Furthermore, there was not any significant difference between term and preterm mother's milk. In conclusion, this is the first study to investigate the concentrations of CXCR-1 and CXCR-2 with the levels of IL-8 in colostrum and mature human milk of term and preterm newborns. The alterations in IL-8 levels were similar in some of the studies reported. CXCR-1 and CXCR-2 levels did not demonstrate any significant difference. Further studies are required to investigate the soluble forms of these receptors and their relation to IL-8 with larger cohort.

  14. Sphingosine 1-phosphate receptor activation enhances BMP-2-induced osteoblast differentiation

    International Nuclear Information System (INIS)

    Sato, Chieri; Iwasaki, Tsuyoshi; Kitano, Sachie; Tsunemi, Sachi; Sano, Hajime

    2012-01-01

    Highlights: ► We investigated the role of S1P signaling for osteoblast differentiation. ► Both S1P and FTY enhanced BMP-2-stimulated osteoblast differentiation by C2C12 cells. ► S1P signaling enhanced BMP-2-stimulated Smad and ERK phosphorylation by C2C12 cells. ► MEK/ERK signaling is a pathway underlying S1P signaling for osteoblast differentiation. -- Abstract: We previously demonstrated that sphingosine 1-phosphate (S1P) receptor-mediated signaling induced proliferation and prostaglandin productions by synovial cells from rheumatoid arthritis (RA) patients. In the present study we investigated the role of S1P receptor-mediated signaling for osteoblast differentiation. We investigated osteoblast differentiation using C2C12 myoblasts, a cell line derived from murine satellite cells. Osteoblast differentiation was induced by the treatment of bone morphogenic protein (BMP)-2 in the presence or absence of either S1P or FTY720 (FTY), a high-affinity agonist of S1P receptors. Osteoblast differentiation was determined by osteoblast-specific transcription factor, Runx2 mRNA expression, alkaline phosphatase (ALP) activity and osteocalcin production by the cells. Smad1/5/8 and extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was examined by Western blotting. Osteocalcin production by C2C12 cells were determined by ELISA. Runx2 expression and ALP activity by BMP-2-stimulated C2C12 cells were enhanced by addition of either S1P or FTY. Both S1P and FTY enhanced BMP-2-induced ERK1/2 and Smad1/5/8 phosphorylation. The effect of FTY was stronger than that of S1P. S1P receptor-mediated signaling on osteoblast differentiation was inhibited by addition of mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, indicating that the S1P receptor-mediated MEK1/2-ERK1/2 signaling pathway enhanced BMP-2-Smad signaling. These results indicate that S1P receptor-mediated signaling plays a crucial role for osteoblast differentiation.

  15. Activation of macrophages by a laccase-polymerized polyphenol is dependent on phosphorylation of Rac1.

    Science.gov (United States)

    Tajima, Katsuya; Akanuma, Satoshi; Matsumoto-Akanuma, Akiko; Yamanaka, Daisuke; Ishibashi, Ken-Ichi; Adachi, Yoshiyuki; Ohno, Naohito

    2018-01-15

    Various physiologically active effects of polymerized polyphenols have been reported. In this study, we synthesized a polymerized polyphenol (mL2a-pCA) by polymerizing caffeic acid using mutant Agaricus brasiliensis laccase and analyzed its physiological activity and mechanism of action. We found that mL2a-pCA induced morphological changes and the production of cytokines and chemokines in C3H/HeN mouse-derived resident peritoneal macrophages in vitro. The mechanisms of action of polymerized polyphenols on in vitro mouse resident peritoneal cells have not been characterized in detail previously. Herein, we report that the mL2a-pCA-induced production of interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in C3H/HeN mouse-derived resident peritoneal cells was inhibited by treatment with the Rac1 inhibitor NSC23766 trihydrochloride. In addition, we found that mL2a-pCA activated the phosphorylation Rac1. Taken together, the results show that mL2a-pCA induced macrophage activation via Rac1 phosphorylation-dependent pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Tyrosine phosphorylation switching of a G protein.

    Science.gov (United States)

    Li, Bo; Tunc-Ozdemir, Meral; Urano, Daisuke; Jia, Haiyan; Werth, Emily G; Mowrey, David D; Hicks, Leslie M; Dokholyan, Nikolay V; Torres, Matthew P; Jones, Alan M

    2018-03-30

    Heterotrimeric G protein complexes are molecular switches relaying extracellular signals sensed by G protein-coupled receptors (GPCRs) to downstream targets in the cytoplasm, which effect cellular responses. In the plant heterotrimeric GTPase cycle, GTP hydrolysis, rather than nucleotide exchange, is the rate-limiting reaction and is accelerated by a receptor-like regulator of G signaling (RGS) protein. We hypothesized that posttranslational modification of the Gα subunit in the G protein complex regulates the RGS-dependent GTPase cycle. Our structural analyses identified an invariant phosphorylated tyrosine residue (Tyr 166 in the Arabidopsis Gα subunit AtGPA1) located in the intramolecular domain interface where nucleotide binding and hydrolysis occur. We also identified a receptor-like kinase that phosphorylates AtGPA1 in a Tyr 166 -dependent manner. Discrete molecular dynamics simulations predicted that phosphorylated Tyr 166 forms a salt bridge in this interface and potentially affects the RGS protein-accelerated GTPase cycle. Using a Tyr 166 phosphomimetic substitution, we found that the cognate RGS protein binds more tightly to the GDP-bound Gα substrate, consequently reducing its ability to accelerate GTPase activity. In conclusion, we propose that phosphorylation of Tyr 166 in AtGPA1 changes the binding pattern with AtRGS1 and thereby attenuates the steady-state rate of the GTPase cycle. We coin this newly identified mechanism "substrate phosphoswitching." © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  17. Interleukin-6, interleukin-8, and soluble tumor necrosis factor receptor-I in the cord blood as predictors of chronic lung disease in premature infants.

    Science.gov (United States)

    An, Hiromi; Nishimaki, Shigeru; Ohyama, Makiko; Haruki, Atsushi; Naruto, Takuya; Kobayashi, Naoki; Sugai, Toshiyuki; Kobayashi, Yoshinori; Mori, Masaaki; Seki, Kazuo; Yokota, Shumpei

    2004-11-01

    In order to predict the late-development of chronic lung disease of prematurity (CLD), cytokines in the cord blood were assessed in this study. Eighteen premature infants with CLD were enrolled. Cord blood plasma levels of cytokines of these infants and 12 control infants without CLD were measured including interleukin (IL)-1beta, IL-2, IL-4, IL-6, IL-8, IL-10, interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, soluble TNF receptor-I, and soluble IL-6 receptor using a cytometric bead array and an enzyme-linked immunosorbent assay. The cord blood IL-6, IL-8, and sTNFR-I levels were significantly elevated in CLD infants compared with those in control (P < .05). IL-1beta, IL-2, IL-4, IL-10, and IFN-gamma were undetectable in both groups. CLD infants with maternal chorioamnionitis had higher IL-6 than those without chorioamnionitis (P < .01). In CLD infants, IL-6 was higher in the infants who required prolonged oxygen therapy (P < .05). Elevated inflammatory cytokines in the cord blood are associated with the progression to CLD.

  18. PKA regulates calcineurin function through the phosphorylation of RCAN1: Identification of a novel phosphorylation site

    International Nuclear Information System (INIS)

    Kim, Seon Sook; Lee, Eun Hye; Lee, Kooyeon; Jo, Su-Hyun; Seo, Su Ryeon

    2015-01-01

    Calcineurin is a calcium/calmodulin-dependent phosphatase that has been implicated in T cell activation through the induction of nuclear factors of activated T cells (NFAT). We have previously suggested that endogenous regulator of calcineurin (RCAN1, also known as DSCR1) is targeted by protein kinase A (PKA) for the control of calcineurin activity. In the present study, we characterized the PKA-mediated phosphorylation site in RCAN1 by mass spectrometric analysis and revealed that PKA directly phosphorylated RCAN1 at the Ser 93. PKA-induced phosphorylation and the increase in the half-life of the RCAN1 protein were prevented by the substitution of Ser 93 with Ala (S93A). Furthermore, the PKA-mediated phosphorylation of RCAN1 at Ser 93 potentiated the inhibition of calcineurin-dependent pro-inflammatory cytokine gene expression by RCAN1. Our results suggest the presence of a novel phosphorylation site in RCAN1 and that its phosphorylation influences calcineurin-dependent inflammatory target gene expression. - Highlights: • We identify novel phosphorylation sites in RCAN1 by LC-MS/MS analysis. • PKA-dependent phosphorylation of RCAN1 at Ser 93 inhibits calcineurin-mediated intracellular signaling. • We show the immunosuppressive function of RCAN1 phosphorylation at Ser 93 in suppressing cytokine expression

  19. Tyrosine phosphorylation of platelet derived growth factor β receptors in coronary artery lesions: implications for vascular remodelling after directional coronary atherectomy and unstable angina pectoris

    Science.gov (United States)

    Abe, J; Deguchi, J; Takuwa, Y; Hara, K; Ikari, Y; Tamura, T; Ohno, M; Kurokawa, K

    1998-01-01

    Background—Growth factors such as platelet derived growth factor (PDGF) have been postulated to be important mediators of neointimal proliferation observed in atherosclerotic plaques and restenotic lesions following coronary interventions. Binding of PDGF to its receptor results in intrinsic receptor tyrosine kinase activation and subsequent cellular migration, proliferation, and vascular contraction.
Aims—To investigate whether the concentration of PDGF β receptor tyrosine phosphorylation obtained from directional coronary atherectomy (DCA) samples correlate with atherosclerotic plaque burden, the ability of diseased vessels to remodel, coronary risk factors, and clinical events.
Methods—DCA samples from 59 patients and 15 non-atherosclerotic left internal thoracic arteries (LITA) were analysed for PDGF β receptor tyrosine phosphorylation content by receptor immunoprecipitation and antiphosphotyrosine western blot. The amount of PDGF β receptor phosphorylation was analysed in relation to angiographic follow up data and clinical variables.
Results—PDGF β receptor tyrosine phosphorylation in the 59 DCA samples was greater than in the 15 non-atherosclerotic LITA (mean (SD) 0.84 (0.67) v 0.17 (0.08) over a control standard, p atherectomy;  restenosis PMID:9616351

  20. Mechanical stress activates Smad pathway through PKCδ to enhance interleukin-11 gene transcription in osteoblasts.

    Directory of Open Access Journals (Sweden)

    Shinsuke Kido

    Full Text Available BACKGROUND: Mechanical stress rapidly induces ΔFosB expression in osteoblasts, which binds to interleukin (IL-11 gene promoter to enhance IL-11 expression, and IL-11 enhances osteoblast differentiation. Because bone morphogenetic proteins (BMPs also stimulate IL-11 expression in osteoblasts, there is a possibility that BMP-Smad signaling is involved in the enhancement of osteoblast differentiation by mechanical stress. The present study was undertaken to clarify whether mechanical stress affects BMP-Smad signaling, and if so, to elucidate the role of Smad signaling in mechanical stress-induced enhancement of IL-11 gene transcription. METHODOLOGY/PRINCIPAL FINDINGS: Mechanical loading by fluid shear stress (FSS induced phosphorylation of BMP-specific receptor-regulated Smads (BR-Smads, Smad1/5, in murine primary osteoblasts (mPOBs. FSS rapidly phosphorylated Y311 of protein kinase C (PKCδ, and phosphorylated PKCδ interacted with BR-Smads to phosphorylate BR-Smads. Transfection of PKCδ siRNA or Y311F mutant PKCδ abrogated BR-Smads phosphorylation and suppressed IL-11 gene transcription enhanced by FSS. Activated BR-Smads bound to the Smad-binding element (SBE of IL-11 gene promoter and formed complex with ΔFosB/JunD heterodimer via binding to the C-terminal region of JunD. Site-directed mutagenesis in the SBE and the AP-1 site revealed that both SBE and AP-1 sites were required for full activation of IL-11 gene promoter by FSS. CONCLUSIONS/SIGNIFICANCE: These results demonstrate that PKCδ-BR-Smads pathway plays an important role in the intracellular signaling in response to mechanical stress, and that a cross-talk between PKCδ-BR-Smads and ΔFosB/JunD pathways synergistically stimulates IL-11 gene transcription in response to mechanical stress.

  1. IL-1RI (Interleukin-1 Receptor Type I Signalling is Essential for Host Defence and Hemichannel Activity During Acute Central Nervous System Bacterial Infection

    Directory of Open Access Journals (Sweden)

    Juan Xiong

    2012-03-01

    Full Text Available Staphylococcus aureus is a common aetiological agent of bacterial brain abscesses. We have previously established that a considerable IL-1 (interleukin-1 response is elicited immediately following S. aureus infection, where the cytokine can exert pleiotropic effects on glial activation and blood–brain barrier permeability. To assess the combined actions of IL-1α and IL-1β during CNS (central nervous system infection, host defence responses were evaluated in IL-1RI (IL-1 receptor type I KO (knockout animals. IL-1RI KO mice were exquisitely sensitive to intracerebral S. aureus infection, as demonstrated by enhanced mortality rates and bacterial burdens within the first 24 h following pathogen exposure compared with WT (wild-type animals. Loss of IL-1RI signalling also dampened the expression of select cytokines and chemokines, concomitant with significant reductions in neutrophil and macrophage infiltrates into the brain. In addition, the opening of astrocyte hemichannels during acute infection was shown to be dependent on IL-1RI activity. Collectively, these results demonstrate that IL-1RI signalling plays a pivotal role in the genesis of immune responses during the acute stage of brain abscess development through S. aureus containment, inflammatory mediator production, peripheral immune cell recruitment, and regulation of astrocyte hemichannel activity. Taken in the context of previous studies with MyD88 (myeloid differentiation primary response gene 88 and TLR2 (Toll-like receptor 2 KO animals, the current report advances our understanding of MyD88-dependent cascades and implicates IL-1RI signalling as a major antimicrobial effector pathway during acute brain-abscess formation.

  2. Interleukin 1B variant -1473G/C (rs1143623) influences triglyceride and interleukin 6 metabolism

    Science.gov (United States)

    Interleukin 1b (IL1B or IL-1ß), is a key modulator of the immune response which exerts its functions mainly via interleukin 6 (IL6) regulation. Fatty meals cause transient hypertriglyceridemia and are considered to be proinflammatory, but the extent of these responses shows high interindividual susc...

  3. β-Arrestin regulation of myosin light chain phosphorylation promotes AT1aR-mediated cell contraction and migration.

    Directory of Open Access Journals (Sweden)

    Elie Simard

    Full Text Available Over the last decade, it has been established that G-protein-coupled receptors (GPCRs signal not only through canonical G-protein-mediated mechanisms, but also through the ubiquitous cellular scaffolds β-arrestin-1 and β-arrestin-2. Previous studies have implicated β-arrestins as regulators of actin reorganization in response to GPCR stimulation while also being required for membrane protrusion events that accompany cellular motility. One of the most critical events in the active movement of cells is the cyclic phosphorylation and activation of myosin light chain (MLC, which is required for cellular contraction and movement. We have identified the myosin light chain phosphatase Targeting Subunit (MYPT-1 as a binding partner of the β-arrestins and found that β-arrestins play a role in regulating the turnover of phosphorylated myosin light chain. In response to stimulation of the angiotensin Type 1a Receptor (AT1aR, MLC phosphorylation is induced quickly and potently. We have found that β-arrestin-2 facilitates dephosphorylation of MLC, while, in a reciprocal fashion, β-arrestin 1 limits dephosphorylation of MLC. Intriguingly, loss of either β-arrestin-1 or 2 blocks phospho-MLC turnover and causes a decrease in the contraction of cells as monitored by atomic force microscopy (AFM. Furthermore, by employing the β-arrestin biased ligand [Sar(1,Ile(4,Ile(8]-Ang, we demonstrate that AT1aR-mediated cellular motility involves a β-arrestin dependent component. This suggests that the reciprocal regulation of MLC phosphorylation status by β-arrestins-1 and 2 causes turnover in the phosphorylation status of MLC that is required for cell contractility and subsequent chemotaxic motility.

  4. The Fyn tyrosine kinase binds Irs-1 and forms a distinct signaling complex during insulin stimulation.

    Science.gov (United States)

    Sun, X J; Pons, S; Asano, T; Myers, M G; Glasheen, E; White, M F

    1996-05-03

    Irs-proteins link the receptors for insulin/IGF-1, growth hormones, and several interleukins and interferons to signaling proteins that contain Src homology-2 (SH2). To identify new Irs-1-binding proteins, we screened a mouse embryo expression library with recombinant [32P]Irs-1, which revealed a specific association between p59fyn and Irs-1. The SH2 domain in p59fyn bound to phosphorylated Tyr895 and Tyr1172, which are located in YXX(L/I) motifs. Mutation of p59fyn at the COOH-terminal tyrosine phosphorylation site (Tyr531) enhanced its binding to Irs-1 during insulin stimulation. Binding experiments with various SH2 protein revealed that Grb-2 was largely excluded from Irs-1 complexes containing p59fyn, whereas Grb-2 and p85 occurred in the same Irs-1 complex. By comparison with the insulin receptor, p59fyn kinase phosphorylated a unique cohort of tyrosine residues in Irs-1. These results outline a role for p59fyn or other related Src-kinases during insulin and cytokine signaling.

  5. Topical interleukin 1 receptor antagonist for treatment of dry eye disease: a randomized clinical trial.

    Science.gov (United States)

    Amparo, Francisco; Dastjerdi, Mohammad H; Okanobo, Andre; Ferrari, Giulio; Smaga, Leila; Hamrah, Pedram; Jurkunas, Ula; Schaumberg, Debra A; Dana, Reza

    2013-06-01

    The immunopathogenic mechanisms of dry eye disease (DED), one of the most common ophthalmic conditions, is incompletely understood. Data from this prospective, double-masked, randomized trial demonstrate that targeting interleukin 1 (IL-1) by topical application of an IL-1 antagonist is efficacious in significantly reducing DED-related patient symptoms and corneal epitheliopathy. To evaluate the safety and efficacy of treatment with the topical IL-1 receptor antagonist anakinra (Kineret; Amgen Inc) in patients having DED associated with meibomian gland dysfunction. Prospective phase 1/2, randomized, double-masked, vehicle-controlled clinical trial. Seventy-five patients with refractory DED. Participants were randomized to receive treatment with topical anakinra, 2.5% (n = 30), anakinra, 5% (n = 15), or vehicle (1% carboxymethylcellulose) (n = 30) 3 times daily for 12 weeks. Primary outcomes were corneal fluorescein staining (CFS), complete bilateral CFS clearance, dry eye-related symptoms as measured by the Ocular Surface Disease Index, tear film breakup time, and meibomian gland secretion quality. Topical anakinra was well tolerated compared with vehicle, with no reports of serious adverse reactions attributable to the therapy. After 12 weeks of therapy, participants treated with anakinra, 2.5%, achieved a 46% reduction in their mean CFS score (P = .12 compared with vehicle and P treatment with anakinra, 2.5%, and treatment with anakinra, 5%, led to significant reductions in symptoms of 30% and 35%, respectively (P = .02 and P = .01, respectively, compared with vehicle); treatment with vehicle led to a 5% reduction in symptoms. Treatment with topical anakinra, 2.5%, for 12 weeks was safe and significantly reduced symptoms and corneal epitheliopathy in patients with DED. These data suggest that the use of an IL-1 antagonist may have a role as a novel therapeutic option for patients with DED. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00681109.

  6. Sphingosine 1-phosphate (S1P) suppresses the collagen-induced activation of human platelets via S1P4 receptor.

    Science.gov (United States)

    Onuma, Takashi; Tanabe, Kumiko; Kito, Yuko; Tsujimoto, Masanori; Uematsu, Kodai; Enomoto, Yukiko; Matsushima-Nishiwaki, Rie; Doi, Tomoaki; Nagase, Kiyoshi; Akamatsu, Shigeru; Tokuda, Haruhiko; Ogura, Shinji; Iwama, Toru; Kozawa, Osamu; Iida, Hiroki

    2017-08-01

    Sphingosine 1-phosphate (S1P) is as an extracellular factor that acts as a potent lipid mediator by binding to specific receptors, S1P receptors (S1PRs). However, the precise role of S1P in human platelets that express S1PRs has not yet been fully clarified. We previously reported that heat shock protein 27 (HSP27) is released from human platelets accompanied by its phosphorylation stimulated by collagen. In the present study, we investigated the effect of S1P on the collagen-induced platelet activation. S1P pretreatment markedly attenuated the collagen-induced aggregation. Co-stimulation with S1P and collagen suppressed collagen-induced platelet activation, but the effect was weaker than that of S1P-pretreatment. The collagen-stimulated secretion of platelet-derived growth factor (PDGF)-AB and the soluble CD40 ligand (sCD40L) release were significantly reduced by S1P. In addition, S1P suppressed the collagen-induced release of HSP27 as well as the phosphorylation of HSP27. S1P significantly suppressed the collagen-induced phosphorylation of p38 mitogen-activated protein kinase. S1P increased the levels of GTP-bound Gαi and GTP-bound Gα13 coupled to S1PPR1 and/or S1PR4. CYM50260, a selective S1PR4 agonist, but not SEW2871, a selective S1PR1 agonist, suppressed the collagen-stimulated platelet aggregation, PDGF-AB secretion and sCD40L release. In addition, CYM50260 reduced the release of phosphorylated-HSP27 by collagen as well as the phosphorylation of HSP27. The selective S1PR4 antagonist CYM50358, which failed to affect collagen-induced HSP27 phosphorylation, reversed the S1P-induced attenuation of HSP27 phosphorylation by collagen. These results strongly suggest that S1P inhibits the collagen-induced human platelet activation through S1PR4 but not S1PR1. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

    Science.gov (United States)

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

    2016-07-01

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

  8. Differential Expression of the Activator Protein 1 Transcription Factor Regulates Interleukin-1ß Induction of Interleukin 6 in the Developing Enterocyte.

    Directory of Open Access Journals (Sweden)

    Catherine M Cahill

    Full Text Available The innate immune response is characterized by activation of transcription factors, nuclear factor kappa B and activator protein-1 and their downstream targets, the pro-inflammatory cytokines including interleukin 1β and interleukin 6. Normal development of this response in the intestine is critical to survival of the human neonate and delays can cause the onset of devastating inflammatory diseases such as necrotizing enterocolitis. Previous studies have addressed the role of nuclear factor kappa B in the development of the innate immune response in the enterocyte, however despite its central role in the control of multiple pro-inflammatory cytokine genes, little is known on the role of Activator Protein 1 in this response in the enterocyte. Here we show that the canonical Activator Protein 1 members, cJun and cFos and their upstream kinases JNK and p38 play an essential role in the regulation of interleukin 6 in the immature enterocyte. Our data supports a model whereby the cFos/cJun heterodimer and the more potent cJun homodimer downstream of JNK are replaced by less efficient JunD containing dimers, contributing to the decreased responsiveness to interleukin 1β and decreased interleukin 6 secretion observed in the mature enterocyte. The tissue specific expression of JunB in colonocytes and colon derived tissues together with its ability to repress Interleukin-1β induction of an Interleukin-6 gene reporter in the NCM-460 colonocyte suggests that induction of JunB containing dimers may offer an attractive therapeutic strategy for the control of IL-6 secretion during inflammatory episodes in this area of the intestine.

  9. Biodistribution of an anti-interleukin 2 receptor monoclonal antibody in rat recipients of a heart allograft, and its use as a rejection marker in gamma scintigraphy

    International Nuclear Information System (INIS)

    Thedrez, P.; Paineau, J.; Jacques, Y.; Chatal, J.F.; Pelegrin, A.; Bouchaud, C.; Soulillou, J.P.

    1989-01-01

    Anti-interleukin-2 receptor monoclonal antibodies have been shown to prevent allograft rejection. This paper reports on the biodistribution of a mouse MoAb directed at the 55 Kd alpha chain of rat interleukin-2 receptor (IL2-R) during allograft rejection. Only a low percentage (approximately 1%) of intact 125I-labeled MoAb was detected in the rejected graft, and irrelevant control IgG1 was found at a similar level. This suggests that most of the injected intact MoAb bound to graft tissue via its monomorphic Fc segment. In contrast, OX39 F(ab')2 fragments showed a preferential localization in the rejected allograft and did not bind to the LEW-to-LEW syngeneic heart graft. Irrelevant F(ab')2 did not concentrate in the allogeneic graft. Accordingly, F(ab')2 fragments from OX39 or irrelevant MoAb were used for gamma-scintigraphy on allograft recipients together with biodistribution studies. Results show that scintigraphy was able to detect allograft accumulation of 131I OX39 F(ab')2, whereas no imaging was obtained when OX39 F(ab')2 was used in the syngeneic combination or when irrelevant 131-IgG1 F(ab')2 was given to allograft recipients. This method, applied to the clinical situation, could be of interest for detection of early graft rejection episodes by immunoscintigraphy using reagents specific for activation determinants on lymphocyte membranes, such as anti-interleukin-2 receptor MoAb

  10. Inhibition of the Transforming Growth Factor β (TGFβ) Pathway by Interleukin-1β Is Mediated through TGFβ-activated Kinase 1 Phosphorylation of SMAD3

    NARCIS (Netherlands)

    Benus, G.F.J.D.; Wierenga, A.T. J.; de Gorter, D.J.J.; Schuringa, Jan-Jacob; van Bennekum, A.M.; Drenth - Diephuis, L.; Vellenga, E.; Eggen, B.J.L.

    2005-01-01

    Transforming growth factor β is the prototype of a large family of secreted factors that regulate multiple biological processes. In the immune system, TGFβ acts as an anti-inflammatory and immunosuppressive molecule, whereas the cytokine interleukin (IL)-1β is a crucial mediator of inflammatory

  11. IRS-1: essential for insulin- and IL-4-stimulated mitogenesis in hematopoietic cells.

    Science.gov (United States)

    Wang, L M; Myers, M G; Sun, X J; Aaronson, S A; White, M; Pierce, J H

    1993-09-17

    Although several interleukin-3 (IL-3)-dependent cell lines proliferate in response to IL-4 or insulin, the 32D line does not. Insulin and IL-4 sensitivity was restored to 32D cells by expression of IRS-1, the principal substrate of the insulin receptor. Although 32D cells possessed receptors for both factors, they lacked the IRS-1--related protein, 4PS, which becomes phosphorylated by tyrosine in insulin- or IL-4--responsive lines after stimulation. These results indicate that factors that bind unrelated receptors can use similar mitogenic signaling pathways in hematopoietic cells and that 4PS and IRS-1 are functionally similar proteins that are essential for insulin- and IL-4--induced proliferation.

  12. Contraction regulates site-specific phosphorylation of TBC1D1 in skeletal muscle.

    Science.gov (United States)

    Vichaiwong, Kanokwan; Purohit, Suneet; An, Ding; Toyoda, Taro; Jessen, Niels; Hirshman, Michael F; Goodyear, Laurie J

    2010-10-15

    TBC1D1 (tre-2/USP6, BUB2, cdc16 domain family member 1) is a Rab-GAP (GTPase-activating protein) that is highly expressed in skeletal muscle, but little is known about TBC1D1 regulation and function. We studied TBC1D1 phosphorylation on three predicted AMPK (AMP-activated protein kinase) phosphorylation sites (Ser231, Ser660 and Ser700) and one predicted Akt phosphorylation site (Thr590) in control mice, AMPKα2 inactive transgenic mice (AMPKα2i TG) and Akt2-knockout mice (Akt2 KO). Muscle contraction significantly increased TBC1D1 phosphorylation on Ser231 and Ser660, tended to increase Ser700 phosphorylation, but had no effect on Thr590. AICAR (5-aminoimidazole-4-carboxyamide ribonucleoside) also increased phosphorylation on Ser231, Ser660 and Ser700, but not Thr590, whereas insulin only increased Thr590 phosphorylation. Basal and contraction-stimulated TBC1D1 Ser231, Ser660 and Ser700 phosphorylation were greatly reduced in AMPKα2i TG mice, although contraction still elicited a small increase in phosphorylation. Akt2 KO mice had blunted insulin-stimulated TBC1D1 Thr590 phosphorylation. Contraction-stimulated TBC1D1 Ser231 and Ser660 phosphorylation were normal in high-fat-fed mice. Glucose uptake in vivo was significantly decreased in tibialis anterior muscles overexpressing TBC1D1 mutated on four predicted AMPK phosphorylation sites. In conclusion, contraction causes site-specific phosphorylation of TBC1D1 in skeletal muscle, and TBC1D1 phosphorylation on AMPK sites regulates contraction-stimulated glucose uptake. AMPK and Akt regulate TBC1D1 phosphorylation, but there must be additional upstream kinases that mediate TBC1D1 phosphorylation in skeletal muscle.

  13. HSF1 stress response pathway regulates autophagy receptor SQSTM1/p62-associated proteostasis

    Science.gov (United States)

    Watanabe, Yoshihisa; Tsujimura, Atsushi; Taguchi, Katsutoshi; Tanaka, Masaki

    2017-01-01

    ABSTRACT Proteostasis is important for protecting cells from harmful proteins and is mainly controlled by the HSF1 (heat shock transcription factor 1) stress response pathway. This pathway facilitates protein refolding by molecular chaperones; however, it is unclear whether it functions in autophagy or inclusion formation. The autophagy receptor SQSTM1/p62 is involved in selective autophagic clearance and inclusion formation by harmful proteins, and its phosphorylation at S349, S403, and S407 is required for binding to substrates. Here, we demonstrate that casein kinase 1 phosphorylates the SQSTM1 S349 residue when harmful proteins accumulate. Investigation of upstream factors showed that both SQSTM1 S349 and SQSTM1 S403 residues were phosphorylated in an HSF1 dependent manner. Inhibition of SQSTM1 phosphorylation suppressed inclusion formation by ubiquitinated proteins and prevented colocalization of SQSTM1 with aggregation-prone proteins. Moreover, HSF1 inhibition impaired aggregate-induced autophagosome formation and elimination of protein aggregates. Our findings indicate that HSF1 triggers SQSTM1-mediated proteostasis. PMID:27846364

  14. HSF1 stress response pathway regulates autophagy receptor SQSTM1/p62-associated proteostasis.

    Science.gov (United States)

    Watanabe, Yoshihisa; Tsujimura, Atsushi; Taguchi, Katsutoshi; Tanaka, Masaki

    2017-01-02

    Proteostasis is important for protecting cells from harmful proteins and is mainly controlled by the HSF1 (heat shock transcription factor 1) stress response pathway. This pathway facilitates protein refolding by molecular chaperones; however, it is unclear whether it functions in autophagy or inclusion formation. The autophagy receptor SQSTM1/p62 is involved in selective autophagic clearance and inclusion formation by harmful proteins, and its phosphorylation at S349, S403, and S407 is required for binding to substrates. Here, we demonstrate that casein kinase 1 phosphorylates the SQSTM1 S349 residue when harmful proteins accumulate. Investigation of upstream factors showed that both SQSTM1 S349 and SQSTM1 S403 residues were phosphorylated in an HSF1 dependent manner. Inhibition of SQSTM1 phosphorylation suppressed inclusion formation by ubiquitinated proteins and prevented colocalization of SQSTM1 with aggregation-prone proteins. Moreover, HSF1 inhibition impaired aggregate-induced autophagosome formation and elimination of protein aggregates. Our findings indicate that HSF1 triggers SQSTM1-mediated proteostasis.

  15. Interleukin 4: signalling mechanisms and control of T cell differentiation.

    Science.gov (United States)

    Paul, W E

    1997-01-01

    Interleukin 4 (IL-4) is a pleiotropic type I cytokine that controls both growth and differentiation among haemopoietic and non-haemopoietic cells. Its receptor is a heterodimer. One chain, the IL-4R alpha chain, binds IL-4 with high affinity and determines the nature of the biochemical signals that are induced. The second chain, gamma c, is required for the induction of such signals. IL-4-mediated growth depends upon activation events that involve phosphorylation of Y497 of IL-4R alpha, leading to the binding and phosphorylation of 4PS/IRS-2 in haemopoietic cells and of IRS-1 in non-haemopoietic cells. By contrast, IL-4-mediated differentiation events depend upon more distal regions of the IL-4R alpha chain that include a series of STAT-6 binding sites. The distinctive roles of these receptor domains was verified by receptor-reconstruction experiments. The 'growth' and 'differentiation' domains of the IL-4R alpha chain, independently expressed as chimeric structures with a truncated version of the IL-2R beta chain, were shown to convey their functions to the hybrid receptor. The critical role of STAT-6 in IL-4-mediated gene activation and differentiation was made clear by the finding that lymphocytes from STAT-6 knockout mice are strikingly deficient in these functions but have retained the capacity to grow, at least partially, in response to IL-4. IL-4 plays a central role in determining the phenotype of naive CD4+ T cells. In the presence of IL-4, newly primed naive T cells develop into IL-4 producers while in its absence they preferentially become gamma-interferon (IFN-gamma) producers. Recently, a specialized subpopulation of T cells, CD4+/NK1.1+ cells, has been shown to produce large amounts of IL-4 upon stimulation. Two examples of mice with deficiencies in these cells are described--beta 2-microglobulin knockout mice and SJL mice. Both show defects in the development of IL-4-producing cells and in the increase in serum IgE in response to stimulation with the

  16. Odin (ANKS1A modulates EGF receptor recycling and stability.

    Directory of Open Access Journals (Sweden)

    Jiefei Tong

    Full Text Available The ANKS1A gene product, also known as Odin, was first identified as a tyrosine-phosphorylated component of the epidermal growth factor receptor network. Here we show that Odin functions as an effector of EGFR recycling. In EGF-stimulated HEK293 cells tyrosine phosphorylation of Odin was induced prior to EGFR internalization and independent of EGFR-to-ERK signaling. Over-expression of Odin increased EGF-induced EGFR trafficking to recycling endosomes and recycling back to the cell surface, and decreased trafficking to lysosomes and degradation. Conversely, Odin knockdown in both HEK293 and the non-small cell lung carcinoma line RVH6849, which expresses roughly 10-fold more EGF receptors than HEK293, caused decreased EGFR recycling and accelerated trafficking to the lysosome and degradation. By governing the endocytic fate of internalized receptors, Odin may provide a layer of regulation that enables cells to contend with receptor cell densities and ligand concentration gradients that are physiologically and pathologically highly variable.

  17. PKCδ-mediated IRS-1 Ser24 phosphorylation negatively regulates IRS-1 function

    International Nuclear Information System (INIS)

    Greene, Michael W.; Ruhoff, Mary S.; Roth, Richard A.; Kim, Jeong-a; Quon, Michael J.; Krause, Jean A.

    2006-01-01

    The IRS-1 PH and PTB domains are essential for insulin-stimulated IRS-1 Tyr phosphorylation and insulin signaling, while Ser/Thr phosphorylation of IRS-1 disrupts these signaling events. To investigate consensus PKC phosphorylation sites in the PH-PTB domains of human IRS-1, we changed Ser24, Ser58, and Thr191 to Ala (3A) or Glu (3E), to block or mimic phosphorylation, respectively. The 3A mutant abrogated the inhibitory effect of PKCδ on insulin-stimulated IRS-1 Tyr phosphorylation, while reductions in insulin-stimulated IRS-1 Tyr phosphorylation, cellular proliferation, and Akt activation were observed with the 3E mutant. When single Glu mutants were tested, the Ser24 to Glu mutant had the greatest inhibitory effect on insulin-stimulated IRS-1 Tyr phosphorylation. PKCδ-mediated IRS-1 Ser24 phosphorylation was confirmed in cells with PKCδ catalytic domain mutants and by an RNAi method. Mechanistic studies revealed that IRS-1 with Ala and Glu point mutations at Ser24 impaired phosphatidylinositol-4,5-bisphosphate binding. In summary, our data are consistent with the hypothesis that Ser24 is a negative regulatory phosphorylation site in IRS-1

  18. HSF1 phosphorylation by ERK/GSK3 suppresses RNF126 to sustain IGF-IIR expression for hypertension-induced cardiomyocyte hypertrophy.

    Science.gov (United States)

    Huang, Chih-Yang; Lee, Fa-Lun; Peng, Shu-Fen; Lin, Kuan-Ho; Chen, Ray-Jade; Ho, Tsung-Jung; Tsai, Fu-Jen; Padma, Vijaya V; Kuo, Wei-Wen; Huang, Chih-Yang

    2018-02-01

    Hypertension-induced cardiac hypertrophy and apoptosis are major characteristics of early-stage heart failure (HF). Inhibition of extracellular signal-regulated kinases (ERK) efficaciously suppressed angiotensin II (ANG II)-induced cardiomyocyte hypertrophy and apoptosis by blocking insulin-like growth factor II receptor (IGF-IIR) signaling. However, the detailed mechanism by which ANG II induces ERK-mediated IGF-IIR signaling remains elusive. Here, we found that ANG II activated ERK to upregulate IGF-IIR expression via the angiotensin II type I receptor (AT 1 R). ERK activation subsequently phosphorylates HSF1 at serine 307, leading to a secondary phosphorylation by glycogen synthase kinase III (GSK3) at serine 303. Moreover, we found that ANG II mediated ERK/GSK3-induced IGF-IIR protein stability by downregulating the E3 ubiquitin ligase of IGF-IIR RING finger protein CXXVI (RNF126). The expression of RNF126 decreased following ANG II-induced HSF1 S303 phosphorylation, resulting in IGF-IIR protein stability and increased cardiomyocyte injury. Inhibition of GSK3 significantly alleviated ANG II-induced cardiac hypertrophy in vivo and in vitro. Taken together, these results suggest that HSF1 phosphorylation stabilizes IGF-IIR protein stability by downregulating RNF126 during cardiac hypertrophy. ANG II activates ERK/GSK3 to phosphorylate HSF1, resulting in RNF126 degradation, which stabilizes IGF-IIR protein expression and eventually results in cardiac hypertrophy. HSF1 could be a valuable therapeutic target for cardiac diseases among hypertensive patients. © 2017 Wiley Periodicals, Inc.

  19. Lapatinib Plasma and Tumor Concentrations and Effects on HER Receptor Phosphorylation in Tumor.

    Directory of Open Access Journals (Sweden)

    Neil L Spector

    Full Text Available The paradigm shift in cancer treatment from cytotoxic drugs to tumor targeted therapies poses new challenges, including optimization of dose and schedule based on a biologically effective dose, rather than the historical maximum tolerated dose. Optimal dosing is currently determined using concentrations of tyrosine kinase inhibitors in plasma as a surrogate for tumor concentrations. To examine this plasma-tumor relationship, we explored the association between lapatinib levels in tumor and plasma in mice and humans, and those effects on phosphorylation of human epidermal growth factor receptors (HER in human tumors.Mice bearing BT474 HER2+ human breast cancer xenografts were dosed once or twice daily (BID with lapatinib. Drug concentrations were measured in blood, tumor, liver, and kidney. In a randomized phase I clinical trial, 28 treatment-naïve female patients with early stage HER2+ breast cancer received lapatinib 1000 or 1500 mg once daily (QD or 500 mg BID before evaluating steady-state lapatinib levels in plasma and tumor.In mice, lapatinib levels were 4-fold higher in tumor than blood with a 4-fold longer half-life. Tumor concentrations exceeded the in vitro IC90 (~ 900 nM or 500 ng/mL for inhibition of HER2 phosphorylation throughout the 12-hour dosing interval. In patients, tumor levels were 6- and 10-fold higher with QD and BID dosing, respectively, compared to plasma trough levels. The relationship between tumor and plasma concentration was complex, indicating multiple determinants. HER receptor phosphorylation varied depending upon lapatinib tumor concentrations, suggestive of changes in the repertoire of HER homo- and heterodimers.Plasma lapatinib concentrations underestimated tumor drug levels, suggesting that optimal dosing should be focused on the site of action to avoid to inappropriate dose escalation. Larger clinical trials are required to determine optimal dose and schedule to achieve tumor concentrations that maximally

  20. E3 Ubiquitin Ligase RNF125 Activates Interleukin-36 Receptor Signaling and Contributes to Its Turnover.

    Science.gov (United States)

    Saha, Siddhartha S; Caviness, Gary; Yi, Guanghui; Raymond, Ernest L; Mbow, M Lamine; Kao, C Cheng

    2018-01-01

    Signaling by the interleukin-36 receptor (IL-36R) is linked to inflammatory diseases such as psoriasis. However, the regulation of IL-36R signaling is poorly understood. Activation of IL-36R signaling in cultured cells results in an increased polyubiquitination of the receptor subunit, IL-1Rrp2. Treatment with deubiquitinases shows that the receptor subunit of IL-36R, IL-1Rrp2, is primarily polyubiquitinated at the K63 position, which is associated with endocytic trafficking and signal transduction. A minor amount of ubiquitination is at the K48 position that is associated with protein degradation. A focused siRNA screen identified RNF125, an E3 ubiquitin ligase, to ubiquitinate IL-1Rrp2 upon activation of IL-36R signaling while not affecting the activated IL-1 receptor. Knockdown of RNF125 decreases signal transduction by the IL-36R. Overexpression of RNF125 in HEK293T cells activates IL-36R signaling and increases the ubiquitination of IL-1Rrp2 and its subsequent turnover. RNF125 can coimmunoprecipitate with the IL-36R, and it traffics with IL-1Rrp2 from the cell surface to lysosomes. Mutations of Lys568 and Lys569 in the C-terminal tail of IL-1Rrp2 decrease ubiquitination by RNF125 and increase the steady-state levels of IL-1Rrp2. These results demonstrate that RNF125 has multiple regulatory roles in the signaling, trafficking, and turnover of the IL-36R. © 2017 S. Karger AG, Basel.

  1. Interleukin-1 receptor antagonist modulates the early phase of liver regeneration after partial hepatectomy in mice.

    Directory of Open Access Journals (Sweden)

    Antonino Sgroi

    Full Text Available BACKGROUND: Cytokine administration is a potential therapy for acute liver failure by reducing inflammatory responses and favour hepatocyte regeneration. The aim of this study was to evaluate the role of interleukin-1 receptor antagonist (IL-1ra during liver regeneration and to study the effect of a recombinant human IL-1ra on liver regeneration. METHODS: We performed 70%-hepatectomy in wild type (WT mice, IL-1ra knock-out (KO mice and in WT mice treated by anakinra. We analyzed liver regeneration at regular intervals by measuring the blood levels of cytokines, the hepatocyte proliferation by bromodeoxyuridin (BrdU incorporation, proliferating cell nuclear antigen (PCNA and Cyclin D1 expression. The effect of anakinra on hepatocyte proliferation was also tested in vitro using human hepatocytes. RESULTS: At 24h and at 48 h after hepatectomy, IL-1ra KO mice had significantly higher levels of pro-inflammatory cytokines (IL-6, IL-1β and MCP-1 and a reduced and delayed hepatocyte proliferation measured by BrdU incorporation, PCNA and Cyclin D1 protein levels, when compared to WT mice. IGFBP-1 and C/EBPβ expression was significantly decreased in IL-1ra KO compared to WT mice. WT mice treated with anakinra showed significantly decreased levels of IL-6 and significantly higher hepatocyte proliferation at 24h compared to untreated WT mice. In vitro, primary human hepatocytes treated with anakinra showed significantly higher proliferation at 24h compared to hepatocytes without treatment. CONCLUSION: IL1ra modulates the early phase of liver regeneration by decreasing the inflammatory stress and accelerating the entry of hepatocytes in proliferation. IL1ra might be a therapeutic target to improve hepatocyte proliferation.

  2. Hypoxemia increases serum interleukin-6 in humans

    DEFF Research Database (Denmark)

    Klausen, T; Olsen, Niels Vidiendal; Poulsen, T D

    1997-01-01

    Serum concentrations of interleukin (IL) 1 beta, IL-1 receptor antagonist (IL-1ra), IL-6, tumor necrosis factor (TNF) alpha, and C-reactive protein (CRP) were determined in ten healthy men at sea level and during four days of altitude hypoxia (4350m above sea level). The mean (SD) arterial blood...

  3. Insulin treatment promotes tyrosine phosphorylation of PKR and inhibits polyIC induced PKR threonine phosphorylation.

    Science.gov (United States)

    Swetha, Medchalmi; Ramaiah, Kolluru V A

    2015-11-01

    Tyrosine phosphorylation of insulin receptor beta (IRβ) in insulin treated HepG2 cells is inversely correlated to ser(51) phosphorylation in the alpha-subunit of eukaryotic initiation factor 2 (eIF2α) that regulates protein synthesis. Insulin stimulates interaction between IRβ and PKR, double stranded RNA-dependent protein kinase, also known as EIF2AK2, and phosphorylation of tyrosine residues in PKR, as analyzed by immunoprecipitation and pull down assays using anti-IRβ and anti-phosphotyrosine antibodies, recombinant IRβ and immunopurified PKR. Further polyIC or synthetic double stranded RNA-induced threonine phosphorylation or activation of immunopurified and cellular PKR is suppressed in the presence of insulin treated purified IRβ and cell extracts. Acute, but not chronic, insulin treatment enhances tyrosine phosphorylation of IRβ, its interaction with PKR and tyrosine phosphorylation of PKR. In contrast, lipopolysaccharide that stimulates threonine phosphorylation of PKR and eIF2α phosphorylation and AG 1024, an inhibitor of the tyrosine kinase activity of IRβ, reduces PKR association with the receptor, IRβ in HepG2 cells. These findings therefore may suggest that tyrosine phosphorylated PKR plays a role in the regulation of insulin induced protein synthesis and in maintaining insulin sensitivity, whereas, suppression of polyIC-mediated threonine phosphorylation of PKR by insulin compromises its ability to fight against virus infection in host cells. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Isoflavones enhance interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

    International Nuclear Information System (INIS)

    Kojima, Hiroyuki; Takeda, Yukimasa; Muromoto, Ryuta; Takahashi, Miki; Hirao, Toru; Takeuchi, Shinji; Jetten, Anton M.; Matsuda, Tadashi

    2015-01-01

    Highlights: • Nuclear receptors, RORα and RORγ, are key regulators of Th17 cell differentiation. • Isoflavones have RORα/γ agonistic activities. • Isoflavones enhance the interaction of RORα/γ with co-activator. • These compounds enhance the expression of Il17a mRNA in mouse EL4 cells. • Dietary isoflavones can act as modulators of Il17a expression via RORα/γ. - Abstract: The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. In this study, we investigated the effects of isoflavones on RORα/γ activity and the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In doxycycline-inducible CHO stable cell lines, we found that four isoflavones, biochanin A (BA), genistein, formononetin, and daidzein, enhanced RORα- or RORγ-mediated transcriptional activity in a dose-dependent manner. In an activation assay of the Il17a promoter using Jurkat cells, these compounds enhanced the RORα- or RORγ-mediated activation of the Il17a promoter at concentrations of 1 × 10 −6 M to 1 × 10 −5 M. In mammalian two-hybrid assays, the four isoflavones enhanced the interaction between the RORα- or RORγ-ligand binding domain and the co-activator LXXLL peptide in a dose-dependent manner. In addition, these isoflavones potently enhanced Il17a mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin, but showed slight enhancement of Il17a gene expression in RORα/γ-knockdown EL4 cells. Immunoprecipitation and immunoblotting assays also revealed that BA enhanced the interaction between RORγt and SRC-1, which is a co-activator for nuclear receptors. Taken together, these results suggest that the isoflavones have the ability to enhance IL-17 gene expression by stabilizing the interactions between RORα/γ and co-activators. This also

  5. Reduced phosphorylation of brain insulin receptor substrate and Akt proteins in apolipoprotein-E4 targeted replacement mice.

    Science.gov (United States)

    Ong, Qi-Rui; Chan, Elizabeth S; Lim, Mei-Li; Cole, Gregory M; Wong, Boon-Seng

    2014-01-17

    Human ApoE4 accelerates memory decline in ageing and in Alzheimer's disease. Although intranasal insulin can improve cognition, this has little effect in ApoE4 subjects. To understand this ApoE genotype-dependent effect, we examined brain insulin signaling in huApoE3 and huApoE4 targeted replacement (TR) mice. At 32 weeks, lower insulin receptor substrate 1 (IRS1) at S636/639 and Akt phosphorylation at T308 were detected in fasting huApoE4 TR mice as compared to fasting huApoE3 TR mice. These changes in fasting huApoE4 TR mice were linked to lower brain glucose content and have no effect on plasma glucose level. However, at 72 weeks of age, these early changes were accompanied by reduction in IRS2 expression, IRS1 phosphorylation at Y608, Akt phosphorylation at S473, and MAPK (p38 and p44/42) activation in the fasting huApoE4 TR mice. The lower brain glucose was significantly associated with higher brain insulin in the aged huApoE4 TR mice. These results show that ApoE4 reduces brain insulin signaling and glucose level leading to higher insulin content.

  6. Sphingosine 1-phosphate receptor activation enhances BMP-2-induced osteoblast differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Chieri [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan); Iwasaki, Tsuyoshi, E-mail: tsuyo-i@huhs.ac.jp [Division of Pharmacotherapy, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, 1-3-6 Minatojima, Chuo-ku, Kobe 650-8530 (Japan); Kitano, Sachie; Tsunemi, Sachi; Sano, Hajime [Division of Rheumatology, Department of Internal Medicine, Hyogo College of Medicine, 1-1 Mukogawa-cho, Nishinomiya, Hyogo 663-8501 (Japan)

    2012-06-22

    Highlights: Black-Right-Pointing-Pointer We investigated the role of S1P signaling for osteoblast differentiation. Black-Right-Pointing-Pointer Both S1P and FTY enhanced BMP-2-stimulated osteoblast differentiation by C2C12 cells. Black-Right-Pointing-Pointer S1P signaling enhanced BMP-2-stimulated Smad and ERK phosphorylation by C2C12 cells. Black-Right-Pointing-Pointer MEK/ERK signaling is a pathway underlying S1P signaling for osteoblast differentiation. -- Abstract: We previously demonstrated that sphingosine 1-phosphate (S1P) receptor-mediated signaling induced proliferation and prostaglandin productions by synovial cells from rheumatoid arthritis (RA) patients. In the present study we investigated the role of S1P receptor-mediated signaling for osteoblast differentiation. We investigated osteoblast differentiation using C2C12 myoblasts, a cell line derived from murine satellite cells. Osteoblast differentiation was induced by the treatment of bone morphogenic protein (BMP)-2 in the presence or absence of either S1P or FTY720 (FTY), a high-affinity agonist of S1P receptors. Osteoblast differentiation was determined by osteoblast-specific transcription factor, Runx2 mRNA expression, alkaline phosphatase (ALP) activity and osteocalcin production by the cells. Smad1/5/8 and extracellular signal-regulated kinase (ERK) 1/2 phosphorylation was examined by Western blotting. Osteocalcin production by C2C12 cells were determined by ELISA. Runx2 expression and ALP activity by BMP-2-stimulated C2C12 cells were enhanced by addition of either S1P or FTY. Both S1P and FTY enhanced BMP-2-induced ERK1/2 and Smad1/5/8 phosphorylation. The effect of FTY was stronger than that of S1P. S1P receptor-mediated signaling on osteoblast differentiation was inhibited by addition of mitogen-activated protein kinase/ERK kinase (MEK) 1/2 inhibitor, indicating that the S1P receptor-mediated MEK1/2-ERK1/2 signaling pathway enhanced BMP-2-Smad signaling. These results indicate that S1P

  7. Increased Level of Phosphorylated ShcA Measured by Chemiluminescence-Linked Immunoassay Is a Predictor of Good Prognosis in Primary Breast Cancer Expressing Low Levels of Estrogen Receptor

    International Nuclear Information System (INIS)

    Cicenas, Jonas; Küng, Willy; Eppenberger, Urs; Eppenberger-Castori, Serenella

    2010-01-01

    The SH2 domain-containing adaptor protein ShcA is a proto-oncogene involved in growth factor receptor signaling. The role of phosphorylated ShcA is to link receptor tyrosine kinases with the SH2-containing adaptor protein Grb2, thus facilitating signal transduction from receptor tyrosine kinases to Ras, leading to MAPK activation. The present study was designed to investigate the prognostic significance of phosphorylated ShcA in primary breast cancer and its association in the interactions between the ER and ErbB2 pathways. Using a two-site chemiluminescence-linked immunosorbent assay, we detected the quantitative expression levels of total tyrosine- and threonine-phosphorylated ShcA in cytosol fractions obtained from fresh frozen tissue samples of 153 selected primary breast cancer patients. ShcA phosphorylation was not associated with nodal status, estrogen receptor (ER) status or grading. High levels of both tyrosine (pYShcA) and serine (pSShcA) phosphorylated ShcA correlated with good prognosis (p < 0.01), with respect to both disease-free (DFS) and overall survival (OS). In addition, pShcA levels were found to correlate with threonine-phosphorylated ErbB2 and inversely with phosphorylated Akt (pAkt), as well as ErbB2 and ER expression levels. Our findings demonstrate that ShcA activation in primary breast cancer patients correlates with low levels of ER, and is associated with good prognosis

  8. Mutation of the SHP-2 binding site in growth hormone (GH) receptor prolongs GH-promoted tyrosyl phosphorylation of GH receptor, JAK2, and STAT5B

    DEFF Research Database (Denmark)

    Stofega, M R; Herrington, J; Billestrup, Nils

    2000-01-01

    phosphorylation. Consistent with the effects on STAT5B phosphorylation, tyrosine-to-phenylalanine mutation of tyrosine 595 prolongs the duration of tyrosyl phosphorylation of GHR and JAK2. These data suggest that tyrosine 595 is a major site of interaction of GHR with SHP-2, and that GHR-bound SHP-2 negatively......Binding of GH to GH receptor (GHR) rapidly and transiently activates multiple signal transduction pathways that contribute to the growth-promoting and metabolic effects of GH. While the events that initiate GH signal transduction, such as activation of the Janus tyrosine kinase JAK2, are beginning...

  9. Insulin receptor substrate proteins create a link between the tyrosine phosphorylation cascade and the Ca2+-ATPases in muscle and heart.

    Science.gov (United States)

    Algenstaedt, P; Antonetti, D A; Yaffe, M B; Kahn, C R

    1997-09-19

    Following phosphorylation by the insulin receptor kinase, the insulin receptor substrates (IRS)-1 and IRS-2 bind to and activate several Src homology 2 (SH2) domain proteins. To identify novel proteins that interact with IRS proteins in muscle, a human skeletal muscle cDNA expression library was created in the lambdaEXlox system and probed with baculovirus-produced and tyrosine-phosphorylated human IRS-1. One clone of the 10 clones which was positive through three rounds of screening represented the C terminus of the human homologue of the adult fast twitch skeletal muscle Ca2+-ATPase (SERCA1) including the cytoplasmic tail and part of transmembrane region 10. Western blot analysis of extracts of rat muscle demonstrated co-immunoprecipitation of both IRS-1 and IRS-2 with the skeletal muscle Ca2+-ATPase (SERCA1) and the cardiac muscle isoform (SERCA2). In both cases, injection of insulin stimulated a 2- to 6-fold increase in association of which was maximal within 5 min. In primary cultures of aortic smooth muscle cells and C2C12 cells, the insulin-stimulated interaction between IRS proteins and SERCA1 and -2 was dose-dependent with a maximum induction at 100 nM insulin. This interaction was confirmed in a "pull down" experiment using a glutathione S-transferase fusion protein containing the C terminus of the human SERCA isoform and phosphorylated IRS-1 in vitro and could be blocked by a FLVRES-like domain peptide present in the human SERCA sequence. Affinity chromatography of phosphopeptide libraries using the glutathione S-transferase fusion protein of the C terminus of SERCA1 indicated a consensus sequence for binding of XpYGSS; this is identical to potential tyrosine phosphorylation sites at position 431 of human IRS-1 and at position 500 of human IRS-2. In streptozotocin diabetic rats the interaction between IRS proteins and SERCA1 in skeletal muscle and SERCA2 in cardiac muscle was significantly reduced. Taken together, these results indicate that the IRS

  10. OsBRI1 Activates BR Signaling by Preventing Binding between the TPR and Kinase Domains of OsBSK3 via Phosphorylation.

    Science.gov (United States)

    Zhang, Baowen; Wang, Xiaolong; Zhao, Zhiying; Wang, Ruiju; Huang, Xiahe; Zhu, Yali; Yuan, Li; Wang, Yingchun; Xu, Xiaodong; Burlingame, Alma L; Gao, Yingjie; Sun, Yu; Tang, Wenqiang

    2016-02-01

    Many plant receptor kinases transduce signals through receptor-like cytoplasmic kinases (RLCKs); however, the molecular mechanisms that create an effective on-off switch are unknown. The receptor kinase BR INSENSITIVE1 (BRI1) transduces brassinosteroid (BR) signal by phosphorylating members of the BR-signaling kinase (BSK) family of RLCKs, which contain a kinase domain and a C-terminal tetratricopeptide repeat (TPR) domain. Here, we show that the BR signaling function of BSKs is conserved in Arabidopsis (Arabidopsis thaliana) and rice (Oryza sativa) and that the TPR domain of BSKs functions as a "phospho-switchable" autoregulatory domain to control BSKs' activity. Genetic studies revealed that OsBSK3 is a positive regulator of BR signaling in rice, while in vivo and in vitro assays demonstrated that OsBRI1 interacts directly with and phosphorylates OsBSK3. The TPR domain of OsBSK3, which interacts directly with the protein's kinase domain, serves as an autoinhibitory domain to prevent OsBSK3 from interacting with bri1-SUPPRESSOR1 (BSU1). Phosphorylation of OsBSK3 by OsBRI1 disrupts the interaction between its TPR and kinase domains, thereby increasing the binding between OsBSK3's kinase domain and BSU1. Our results not only demonstrate that OsBSK3 plays a conserved role in regulating BR signaling in rice, but also provide insight into the molecular mechanism by which BSK family proteins are inhibited under basal conditions but switched on by the upstream receptor kinase BRI1. © 2016 American Society of Plant Biologists. All Rights Reserved.

  11. AMPA receptor phosphorylation and recognition memory: learning-related, time-dependent changes in the chick brain following filial imprinting.

    Science.gov (United States)

    Solomonia, Revaz O; Meparishvili, Maia; Mikautadze, Ekaterine; Kunelauri, Nana; Apkhazava, David; McCabe, Brian J

    2013-04-01

    There is strong evidence that a restricted part of the chick forebrain, the intermediate medial mesopallium (IMM), stores information acquired through the learning process of visual imprinting. We have previously demonstrated that at 1 h but not 24 h after imprinting training, a learning-specific increase in the amount of membrane Thr286-autophosphorylated α-calcium/calmodulin-dependent protein kinase II (αCaMKII), and in the proportion of total αCaMKII that is phosphorylated, occurs in the IMM but not in a control brain region, the posterior pole of the nidopallium (PPN). αCaMKII directly phosphorylates Ser831 in the GluA1 subunit of the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor. In the present study we have inquired whether the learning-related increase in αCaMKII autophosphorylation is followed by changes in the Ser831 phosphorylation of GluA1 (P-GluA1) and in the total amount of this subunit (T-GluA1). Trained chicks together with untrained control chicks were killed either 1 or 24 h after training. Tissue was removed from the IMM together with tissue from the PPN as a control. Amounts of P-GluA1 and T-GluA1 were measured. In the left IMM of the 1 h group the P-GluA1/T-GluA1 ratio increased in a learning-specific way. No learning-related changes were observed in other brain regions at 1 h or in any region 24 h after training. The results indicate that a time- and regionally-dependent, learning-specific increase in GluA1 phosphorylation occurs early in recognition memory formation.

  12. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium.

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2012-02-01

    BACKGROUND: Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. RESULTS: Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. CONCLUSION: Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  13. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    LENUS (Irish Health Repository)

    Dooley, Ruth

    2011-08-22

    Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  14. Purinergic receptor antagonists inhibit odorant-mediated CREB phosphorylation in sustentacular cells of mouse olfactory epithelium

    Directory of Open Access Journals (Sweden)

    Hatt Hanns

    2011-08-01

    Full Text Available Abstract Background Extracellular nucleotides have long been known to play neuromodulatory roles and to be involved in intercellular signalling. In the olfactory system, ATP is released by olfactory neurons, and exogenous ATP can evoke an increase in intracellular calcium concentration in sustentacular cells, the nonneuronal supporting cells of the olfactory epithelium. Here we investigate the hypothesis that olfactory neurons communicate with sustentacular cells via extracellular ATP and purinergic receptor activation. Results Here we show that exposure of mice to a mixture of odorants induced a significant increase in the levels of the transcription factor CREB phosphorylated at Ser-133 in the nuclei of both olfactory sensory neurons and sustentacular cells. This activation was dependent on adenylyl cyclase III-mediated olfactory signaling and on activation of P2Y purinergic receptors on sustentacular cells. Purinergic receptor antagonists inhibited odorant-dependent CREB phosphorylation specifically in the nuclei of the sustentacular cells. Conclusion Our results point to a possible role for extracellular nucleotides in mediating intercellular communication between the neurons and sustentacular cells of the olfactory epithelium in response to odorant exposure. Maintenance of extracellular ionic gradients and metabolism of noxious chemicals by sustentacular cells may therefore be regulated in an odorant-dependent manner by olfactory sensory neurons.

  15. Prognostic significance of interleukin-7 receptor-α gene polymorphisms in allogeneic stem-cell transplantation: a confirmatory study

    DEFF Research Database (Denmark)

    Shamim, Zaiba; Ryder, Lars P; Christensen, Ib J

    2011-01-01

    BACKGROUND: Interleukin-7 (IL-7) is a hematopoietic cytokine essential for T-cell development in the thymus and for the maintenance of peripheral T cells. A previous study of single nucleotide polymorphisms in the exons of IL-7 receptor a-chain (IL-7Ra) in a Danish cohort of patients undergoing a...

  16. Exercise increases TBC1D1 phosphorylation in human skeletal muscle

    Science.gov (United States)

    Jessen, Niels; An, Ding; Lihn, Aina S.; Nygren, Jonas; Hirshman, Michael F.; Thorell, Anders

    2011-01-01

    Exercise and weight loss are cornerstones in the treatment and prevention of type 2 diabetes, and both interventions function to increase insulin sensitivity and glucose uptake into skeletal muscle. Studies in rodents demonstrate that the underlying mechanism for glucose uptake in muscle involves site-specific phosphorylation of the Rab-GTPase-activating proteins AS160 (TBC1D4) and TBC1D1. Multiple kinases, including Akt and AMPK, phosphorylate TBC1D1 and AS160 on distinct residues, regulating their activity and allowing for GLUT4 translocation. In contrast to extensive rodent-based studies, the regulation of AS160 and TBC1D1 in human skeletal muscle is not well understood. In this study, we determined the effects of dietary intervention and a single bout of exercise on TBC1D1 and AS160 site-specific phosphorylation in human skeletal muscle. Ten obese (BMI 33.4 ± 2.4, M-value 4.3 ± 0.5) subjects were studied at baseline and after a 2-wk dietary intervention. Muscle biopsies were obtained from the subjects in the resting (basal) state and immediately following a 30-min exercise bout (70% V̇o2 max). Muscle lysates were analyzed for AMPK activity and Akt phosphorylation and for TBC1D1 and AS160 phosphorylation on known or putative AMPK and Akt sites as follows: AS160 Ser711 (AMPK), TBC1D1 Ser231 (AMPK), TBC1D1 Ser660 (AMPK), TBC1D1 Ser700 (AMPK), and TBC1D1 Thr590 (Akt). The diet intervention that consisted of a major shift in the macronutrient composition resulted in a 4.2 ± 0.4 kg weight loss (P < 0.001) and a significant increase in insulin sensitivity (M value 5.6 ± 0.6), but surprisingly, there was no effect on expression or phosphorylation of any of the muscle-signaling proteins. Exercise increased muscle AMPKα2 activity but did not increase Akt phosphorylation. Exercise increased phosphorylation on AS160 Ser711, TBC1D1 Ser231, and TBC1D1 Ser660 but had no effect on TBC1D1 Ser700. Exercise did not increase TBC1D1 Thr590 phosphorylation or TBC1D1/AS160 PAS

  17. Glycoprotein VI/Fc receptor γ chain-independent tyrosine phosphorylation and activation of murine platelets by collagen

    OpenAIRE

    Jarvis, Gavin E.; Best, Denise; Watson, Steve P.

    2004-01-01

    We have investigated the ability of collagen to induce signalling and functional responses in suspensions of murine platelets deficient in the FcRγ (Fc receptor γ) chain, which lack the collagen receptor GPVI (glycoprotein VI). In the absence of the FcRγ chain, collagen induced a unique pattern of tyrosine phosphorylation which was potentiated by the thromboxane analogue U46619. Immunoprecipitation studies indicated that neither collagen alone nor the combination of collagen plus U46619 induc...

  18. Diversifying selection and functional analysis of interleukin-4 suggests antagonism-driven evolution at receptor-binding interfaces

    Directory of Open Access Journals (Sweden)

    Brown Scott

    2010-07-01

    Full Text Available Abstract Background Interleukin-4 (IL4 is a secreted immunoregulatory cytokine critically involved in host protection from parasitic helminths 1. Reasoning that helminths may have evolved mechanisms to antagonize IL4 to maximize their dispersal, we explored mammalian IL4 evolution. Results This analysis revealed evidence of diversifying selection at 15 residues, clustered in epitopes responsible for IL4 binding to its Type I and Type II receptors. Such a striking signature of selective pressure suggested either recurrent episodes of pathogen antagonism or ligand/receptor co-evolution. To test the latter possibility, we performed detailed functional analysis of IL4 allotypes expressed by Mus musculus musculus and Mus musculus castaneus, which happen to differ at 5 residues (including three at positively selected sites in and adjacent to the site 1 epitope that binds the IL4Rα subunit shared by the Type I and Type II IL4 receptors. We show that this intra-species variation affects the ability of IL4 neither to bind IL4 receptor alpha (IL4Rα nor to signal biological responses through its Type I receptor. Conclusions Our results -- reminiscent of clustered positively selected sites revealing functionally important residues at host-virus interaction interfaces -- are consistent with IL4 having evolved to avoid recurrent pathogen antagonism, while maintaining the capacity to bind and signal through its cognate receptor. This work exposes what may be a general feature of evolutionary conflicts fought by pathogen antagonists at host protein-protein interaction interfaces involved in immune signaling: the emergence of receptor-binding ligand epitopes capable of buffering amino acid variation.

  19. Interleukin-1/toll-like receptor-induced nuclear factor kappa B signaling participates in intima hyperplasia after carotid artery balloon injury in goto-kakizaki rats: a potential target therapy pathway.

    Directory of Open Access Journals (Sweden)

    Xiaotian Zhang

    Full Text Available The value of restenosis after percutaneous coronary intervention (PCI is recognized worldwide, especially for diabetic patients. Interleukin-1/Toll-like receptor (IL-1/TLR signaling is involved in innate and adaptive immune responses, but whether and how the IL-1/TLR-induced nuclear factor kappa B (NFκB pathway plays key roles in intimal formation is unclear. The underlying mechanism of intima hyperplasia was investigated with a model of carotid balloon injury in Goto-Kakizaki (GK and Wistar rats and with lipopolysaccharide-stimulated macrophages. Elastic-van Gieson staining showed the medial area peakedon Day 3 post-injury and decreased by Day 7 post-injury in both GK and Wistar rats. The N/M at Day 7 in GK rats was significantly higher than in Wistar rats (p<0.001. The percent of 5-ethynyl-2'-deoxyuridine (EdU staining-positive cells on Day 3 post-injury was greater than seen on Day 7 post-injury in GK and Wistar rats. The percent of EdU-positive cells on Days 3 and 7 post-injury in Wistar rats was less than that found in GK rats (p<0.01; p<0.05. NFκBp65 immunostaining had increased by Day 7 post-injury. Agilent Whole Genome Oligo Microarray verified that the IL-1/TLR-induced NFκB pathway was activated by carotid balloon injury. TLR4, IL-1 receptor associated kinase, inhibitors α of NFκB, human antigen R, c-Myc (Proto-Oncogene Proteins, EGF-like module-containing mucin-like hormone receptor-like 1 and Interleukin-6 were up-regulated or down-regulated according to immunochemistry, quantitative real-time PCR, Western blotting and Enzyme linked immunosorbent assay. Overall, we conclude that the IL-1/TLR-induced NFκB pathway participates in the intimal hyperplasia after carotid injury in GK and Wistar rats and that GK rats respond more intensely to the inflammation than Wistar rats.

  20. Combination of PKCε Activation and PTP1B Inhibition Effectively Suppresses Aβ-Induced GSK-3β Activation and Tau Phosphorylation.

    Science.gov (United States)

    Kanno, Takeshi; Tsuchiya, Ayako; Tanaka, Akito; Nishizaki, Tomoyuki

    2016-09-01

    Glycogen synthase kinase-3β (GSK-3β) is a key element to phosphorylate tau and form neurofibrillary tangles (NFTs) found in tauopathies including Alzheimer's disease (AD). A current topic for AD therapy is focused upon how to prevent tau phosphorylation. In the present study, PKCε activated Akt and inactivated GSK-3β by directly interacting with each protein. Inhibition of protein tyrosine phosphatase 1B (PTP1B), alternatively, caused an enhancement in the tyrosine phosphorylation of insulin receptor substrate 1 (IRS-1), allowing activation of Akt through a pathway along an IRS-1/phosphatidylinositol 3 kinase (PI3K)/3-phosphoinositide-dependent protein kinase-1 (PDK1)/Akt axis, to phosphorylate and inactivate GSK-3β. Combination of PKCε activation and PTP1B inhibition more sufficiently activated Akt and inactivated GSK-3β than each independent treatment, to suppress amyloid β (Aβ)-induced tau phosphorylation and ameliorate spatial learning and memory impairment in 5xFAD transgenic mice, an animal model of AD. This may represent an innovative strategy for AD therapy.

  1. Sphingosine 1-Phosphate Induces Platelet/Endothelial Cell Adhesion Molecule-1 Tyrosine Phosphorylation in Bovine Aortic Endothelial Cells through a PP2-Inhibitable Mechanism

    Directory of Open Access Journals (Sweden)

    Yu-Ting Huang

    2007-12-01

    Full Text Available Sphingosine-1-phosphate (S1P is a low-molecular-weight phospholipid derivative released by activated platelets. S1P transduces signals through a family of G protein-coupled receptors to modulate various physiological behaviors of endothelial cells. Platelet/endothelial cell adhesion molecule-1 (PECAM-1; CD31 is a 130-kDa protein expressed on the surfaces of leukocytes, platelets, and endothelial cells. Upon PECAM-1 activation, its cytoplasmic tyrosine residues become phosphorylated and bind with SH2 domain-containing proteins, thus leading to the downstream functions mediated by PECAM-1. In the present study, we found that S1P induced PECAM-1 tyrosine phosphorylation and SHP-2 association in bovine aortic endothelial cells (BAECs by immunoprecipitation and western blotting. The pretreatment of BAECs with a series of chemical inhibitors to determine the signaling pathway showed that the PECAM-1 phosphorylation was inhibited by PP2, indicating the participation of Src family kinases. These results demonstrated that S1P induced PECAM-1 tyrosine phosphorylation in BAECs through mediation of Src family kinases, and this may regulate the physiological behaviors of endothelial cells.

  2. Insulin stimulates the tyrosine phosphorylation of a Mr = 160,000 glycoprotein in adipocyte plasma membranes

    International Nuclear Information System (INIS)

    Yu, K.T.; Khalaf, N.; Czech, M.P.

    1986-01-01

    In an attempt to identify putative substrates for the insulin receptor kinase, adipocyte plasma membranes were incubated with [γ- 32 P]ATP in the presence and absence of insulin. Insulin stimulates the tyrosine phosphorylation of its receptor β subunit but does not detectably alter the phosphorylation of other membrane proteins. In contrast, when plasma membranes from insulin-treated adipocytes are phosphorylated, the 32 P-labeling of a Mr=160,000 species (p160) and insulin receptor β subunit are markedly increased when compared to controls. p160 exhibits a rapid response (max. at 1 min) and high sensitivity (ED 50 = 2 x 10 -10 M) to insulin. The stimulatory effect of insulin on the phosphorylation of p160 is rapidly reversed following the addition of anti-insulin serum. Cold chase experiments indicate that insulin promotes the phosphorylation of p160 rather than inhibiting its dephosphorylation. p160 is a glycoprotein as evidenced by its adsorption to immobilized lectins and does not represent the insulin receptor precursor. The action of insulin on p160 tyrosine phosphorylation is mimicked by concanavalin A but not by EGF and other insulin-like agents such as hydrogen peroxide and vanadate. These results suggest that p160 tyrosine phosphorylation is an insulin receptor-mediated event and may participate in signalling by the insulin receptor

  3. Type I and type II interferons upregulate functional type I interleukin-1 receptor in a human fibroblast cell line TIG-1.

    Science.gov (United States)

    Takii, T; Niki, N; Yang, D; Kimura, H; Ito, A; Hayashi, H; Onozaki, K

    1995-12-01

    The regulation of type I interleukin-1 receptor (IL-1R) expression by type I, interferon (IFN)-alpha A/D, and type II IFN, IFN-gamma, in a human fibroblast cell line TIG-1 was investigated. After 2 h stimulation with human IFN-alpha A/D or IFN-gamma, the levels of type I IL-1R mRNA increased. We previously reported that IL-1 upregulates transcription and cell surface molecules of type I IL-1R in TIG-1 cells through induction of prostaglandin (PG) E2 and cAMP accumulation. However, indomethacin was unable to inhibit the effect of IFNs, indicating that IFNs augment IL-1R expression through a pathway distinct from that of IL-1. The augmentation was also observed in other fibroblast cell lines. Nuclear run-on assays and studies of the stability of mRNA suggested that the increase in IL-1R mRNA was a result of the enhanced transcription of IL-1R gene. Binding studies using 125I-IL-1 alpha revealed that the number of cell surface IL-1R increased with no change in binding affinity by treatment with these IFNs. Pretreatment of the cells with IFNs enhanced IL-1-induced IL-6 production, indicating that IFNs upregulate functional IL-1R. IL-1 and IFNs are produced by the same cell types, as well as by the adjacent different cell types, and are concomitantly present in lesions of immune and inflammatory reactions. These results therefore suggest that IFNs exhibit synergistic effects with IL-1 through upregulation of IL-1R. Augmented production of IL-6 may also contribute to the reactions.

  4. Engineering of GlcNAc-1-Phosphotransferase for Production of Highly Phosphorylated Lysosomal Enzymes for Enzyme Replacement Therapy.

    Science.gov (United States)

    Liu, Lin; Lee, Wang-Sik; Doray, Balraj; Kornfeld, Stuart

    2017-06-16

    Several lysosomal enzymes currently used for enzyme replacement therapy in patients with lysosomal storage diseases contain very low levels of mannose 6-phosphate, limiting their uptake via mannose 6-phosphate receptors on the surface of the deficient cells. These enzymes are produced at high levels by mammalian cells and depend on endogenous GlcNAc-1-phosphotransferase α/β precursor to phosphorylate the mannose residues on their glycan chains. We show that co-expression of an engineered truncated GlcNAc-1-phosphotransferase α/β precursor and the lysosomal enzyme of interest in the producing cells resulted in markedly increased phosphorylation and cellular uptake of the secreted lysosomal enzyme. This method also results in the production of highly phosphorylated acid β-glucocerebrosidase, a lysosomal enzyme that normally has just trace amounts of this modification.

  5. P2X7, NMDA and BDNF receptors converge on GSK3 phosphorylation and cooperate to promote survival in cerebellar granule neurons.

    Science.gov (United States)

    Ortega, Felipe; Pérez-Sen, Raquel; Morente, Verónica; Delicado, Esmerilda G; Miras-Portugal, Maria Teresa

    2010-05-01

    Glycogen synthase kinase-3 (GSK3) is a key player in the regulation of neuronal survival. Herein, we report evidence of an interaction between P2X7 receptors with NMDA and BDNF receptors at the level of GSK3 signalling and neuroprotection. The activation of these receptors in granule neurons led to a sustained pattern of GSK3 phosphorylation that was mainly PKC-dependent. BDNF was the most potent at inducing GSK3 phosphorylation, which was also dependent on PI3K. The P2X7 agonist, BzATP, exhibited additive effects with both NMDA and BDNF to rescue granule neurons from cell death induced by PI3K inhibition. This survival effect was mediated by the PKC-dependent GSK3 pathway. In addition, ERK1/2 proteins were also involved in BDNF protective effect. These results show the function of ATP in amplifying neuroprotective actions of glutamate and neurotrophins, and support the role of GSK3 as an important convergence point for these survival promoting factors in granule neurons.

  6. Interleukin-2 induces tyrosine phosphorylation and nuclear translocation of stat3 in human T lymphocytes

    DEFF Research Database (Denmark)

    Nielsen, M; Svejgaard, A; Skov, S

    1994-01-01

    that stimulation through the IL-2R induced tyrosine phosphorylation and subsequent nuclear translocation of stat3, a newly identified member of the signal transducers and activators of transcription (STAT) family of proteins. In contrast, stat1 proteins were not tyrosine phosphorylated after IL-2 ligation, whereas...... an apparent molecular mass of 84 kDa and was not recognized by stat3 or stat1 mAb or antisera. Since IL-2 induced nuclear translocation of the 84 kDa protein and stat3 followed identical kinetics, p84 is a candidate for a new, yet undefined, member of the STAT family. Taken together, we report that IL-2...... induces tyrosine phosphorylation and subsequent nuclear translocation of stat3 and an as yet undefined 84-kDa protein in antigen-specific human T cell lines....

  7. Mechanical stretch augments insulin-induced vascular smooth muscle cell proliferation by insulin-like growth factor-1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Gang [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Department of Anesthesiology, First Affiliated Hospital of China Medical University, Shenyang (China); Hitomi, Hirofumi, E-mail: hitomi@kms.ac.jp [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Hosomi, Naohisa [Department of Cardiorenal and Cerebrovascular Medicine, Faculty of Medicine, Kagawa University, Kagawa (Japan); Lei, Bai; Nakano, Daisuke [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Deguchi, Kazushi; Mori, Hirohito; Masaki, Tsutomu [Department of Gastroenterology and Neurology, Faculty of Medicine, Kagawa University, Kagawa (Japan); Ma, Hong [Department of Anesthesiology, First Affiliated Hospital of China Medical University, Shenyang (China); Griendling, Kathy K. [Department of Medicine, Division of Cardiology, Emory University School of Medicine, Atlanta, GA (United States); Nishiyama, Akira [Department of Pharmacology, Faculty of Medicine, Kagawa University, Kagawa (Japan)

    2011-10-15

    Insulin resistance and hypertension have been implicated in the pathogenesis of cardiovascular disease; however, little is known about the roles of insulin and mechanical force in vascular smooth muscle cell (VSMC) remodeling. We investigated the contribution of mechanical stretch to insulin-induced VSMC proliferation. Thymidine incorporation was stimulated by insulin in stretched VSMCs, but not in un-stretched VSMCs. Insulin increased 2-deoxy-glucose incorporation in both stretched and un-stretched VSMCs. Mechanical stretch augmented insulin-induced extracellular signal-regulated kinase (ERK) and Akt phosphorylation. Inhibitors of epidermal growth factor (EGF) receptor tyrosine kinase and Src attenuated insulin-induced ERK and Akt phosphorylation, as well as thymidine incorporation, whereas 2-deoxy-glucose incorporation was not affected by these inhibitors. Moreover, stretch augmented insulin-like growth factor (IGF)-1 receptor expression, although it did not alter the expression of insulin receptor and insulin receptor substrate-1. Insulin-induced ERK and Akt activation, and thymidine incorporation were inhibited by siRNA for the IGF-1 receptor. Mechanical stretch augments insulin-induced VSMC proliferation via upregulation of IGF-1 receptor, and downstream Src/EGF receptor-mediated ERK and Akt activation. Similar to in vitro experiment, IGF-1 receptor expression was also augmented in hypertensive rats. These results provide a basis for clarifying the molecular mechanisms of vascular remodeling in hypertensive patients with hyperinsulinemia. -- Highlights: {yields} Mechanical stretch augments insulin-induced VSMC proliferation via IGF-1 receptor. {yields} Src/EGFR-mediated ERK and Akt phosphorylation are augmented in stretched VSMCs. {yields} Similar to in vitro experiment, IGF-1 receptor is increased in hypertensive rats. {yields} Results provide possible mechanisms of vascular remodeling in hypertension with DM.

  8. Bach2 represses the AP-1-driven induction of interleukin-2 gene transcription in CD4+ T cells

    OpenAIRE

    Jang, Eunkyeong; Lee, Hye Rim; Lee, Geon Hee; Oh, Ah-Reum; Cha, Ji-Young; Igarashi, Kazuhiko; Youn, Jeehee

    2017-01-01

    The transcription repressor Bach2 has been proposed as a regulator of T cell quiescence, but the underlying mechanism is not fully understood. Given the importance of interleukin-2 in T cell activation, we investigated whether Bach2 is a component of the network of factors that regulates interleukin-2 expression. In primary and transformed CD4+ T cells, Bach2 overexpression counteracted T cell receptor/CD28- or PMA/ionomycin-driven induction of interleukin-2 expression, and silencing of Bach2...

  9. Increased Level of Phosphorylated ShcA Measured by Chemiluminescence-Linked Immunoassay Is a Predictor of Good Prognosis in Primary Breast Cancer Expressing Low Levels of Estrogen Receptor

    Directory of Open Access Journals (Sweden)

    Serenella Eppenberger-Castori

    2010-03-01

    Full Text Available The SH2 domain-containing adaptor protein ShcA is a proto-oncogene involved in growth factor receptor signaling. The role of phosphorylated ShcA is to link receptor tyrosine kinases with the SH2-containing adaptor protein Grb2, thus facilitating signal transduction from receptor tyrosine kinases to Ras, leading to MAPK activation. The present study was designed to investigate the prognostic significance of phosphorylated ShcA in primary breast cancer and its association in the interactions between the ER and ErbB2 pathways. Using a two-site chemiluminescence-linked immunosorbent assay, we detected the quantitative expression levels of total tyrosine- and threonine-phosphorylated ShcA in cytosol fractions obtained from fresh frozen tissue samples of 153 selected primary breast cancer patients. ShcA phosphorylation was not associated with nodal status, estrogen receptor (ER status or grading. High levels of both tyrosine (pYShcA and serine (pSShcA phosphorylated ShcA correlated with good prognosis (p < 0.01, with respect to both disease-free (DFS and overall survival (OS. In addition, pShcA levels were found to correlate with threonine-phosphorylated ErbB2 and inversely with phosphorylated Akt (pAkt, as well as ErbB2 and ER expression levels. Our findings demonstrate that ShcA activation in primary breast cancer patients correlates with low levels of ER, and is associated with good prognosis.

  10. Deficiency of Interleukin-1 Receptor Antagonist (DIRA): Report of the First Indian Patient and a Novel Deletion Affecting IL1RN.

    Science.gov (United States)

    Mendonca, Leonardo O; Malle, Louise; Donovan, Frank X; Chandrasekharappa, Settara C; Montealegre Sanchez, Gina A; Garg, Megha; Tedgard, Ulf; Castells, Mariana; Saini, Shiv S; Dutta, Sourabh; Goldbach-Mansky, Raphaela; Suri, Deepti; Jesus, Adriana A

    2017-07-01

    Deficiency of interleukin-1 receptor antagonist (DIRA) is a rare life-threatening autoinflammatory disease caused by autosomal recessive mutations in IL1RN. DIRA presents clinically with early onset generalized pustulosis, multifocal osteomyelitis, and elevation of acute phase reactants. We evaluated and treated an antibiotic-unresponsive patient with presumed DIRA with recombinant IL-1Ra (anakinra). The patient developed anaphylaxis to anakinra and was subsequently desensitized. Genetic analysis of IL1RN was undertaken and treatment with anakinra was initiated. A 5-month-old Indian girl born to healthy non-consanguineous parents presented at the third week of life with irritability, sterile multifocal osteomyelitis including ribs and clavicles, a mild pustular rash, and elevated acute phase reactants. SNP array of the patient's genomic DNA revealed a previously unrecognized homozygous deletion of approximately 22.5 Kb. PCR and Sanger sequencing of the borders of the deleted area allowed identification of the breakpoints of the deletion, thus confirming a homozygous 22,216 bp deletion that spans the first four exons of IL1RN. Due to a clinical suspicion of DIRA, anakinra was initiated which resulted in an anaphylactic reaction that triggered desensitization with subsequent marked and sustained clinical and laboratory improvement. We report a novel DIRA-causing homozygous deletion affecting IL1RN in an Indian patient. The mutation likely is a founder mutation; the design of breakpoint-specific primers will enable genetic screening in Indian patients suspected of DIRA. The patient developed anaphylaxis to anakinra, was desensitized, and is in clinical remission on continued treatment.

  11. Human GH Receptor-IGF-1 Receptor Interaction: Implications for GH Signaling

    Science.gov (United States)

    Gan, Yujun; Buckels, Ashiya; Liu, Ying; Zhang, Yue; Paterson, Andrew J.; Jiang, Jing; Zinn, Kurt R.

    2014-01-01

    GH signaling yields multiple anabolic and metabolic effects. GH binds the transmembrane GH receptor (GHR) to activate the intracellular GHR-associated tyrosine kinase, Janus kinase 2 (JAK2), and downstream signals, including signal transducer and activator of transcription 5 (STAT5) activation and IGF-1 gene expression. Some GH effects are partly mediated by GH-induced IGF-1 via IGF-1 receptor (IGF-1R), a tyrosine kinase receptor. We previously demonstrated in non-human cells that GH causes formation of a GHR-JAK2-IGF-1R complex and that presence of IGF-1R (even without IGF-1 binding) augments proximal GH signaling. In this study, we use human LNCaP prostate cancer cells as a model system to further study the IGF-1R's role in GH signaling. GH promoted JAK2 and GHR tyrosine phosphorylation and STAT5 activation in LNCaP cells. By coimmunoprecipitation and a new split luciferase complementation assay, we find that GH augments GHR/IGF-1R complex formation, which is inhibited by a Fab of an antagonistic anti-GHR monoclonal antibody. Short hairpin RNA-mediated IGF-1R silencing in LNCaP cells reduced GH-induced GHR, JAK2, and STAT5 phosphorylation. Similarly, a soluble IGF-1R extracellular domain fragment (sol IGF-1R) interacts with GHR in response to GH and blunts GH signaling. Sol IGF-1R also markedly inhibits GH-induced IGF-1 gene expression in both LNCaP cells and mouse primary osteoblast cells. On the basis of these and other findings, we propose a model in which IGF-1R augments GH signaling by allowing a putative IGF-1R-associated molecule that regulates GH signaling to access the activated GHR/JAK2 complex and envision sol IGF-1R as a dominant-negative inhibitor of this IGF-1R-mediated augmentation. Physiological implications of this new model are discussed. PMID:25211187

  12. Expression of Tac antigen component of bovine interleukin-2 receptor in different leukocyte populations infected with Theileria parva or Theileria annulata.

    Science.gov (United States)

    Dobbelaere, D A; Prospero, T D; Roditi, I J; Kelke, C; Baumann, I; Eichhorn, M; Williams, R O; Ahmed, J S; Baldwin, C L; Clevers, H

    1990-01-01

    The Tac antigen component of the bovine interleukin-2 receptor was expressed as a Cro-beta-galactosidase fusion protein in Escherichia coli and used to raise antibodies in rabbits. These antibodies were used for flow cytofluorimetric analysis to investigate the expression of Tac antigen in a variety of Theileria parva-infected cell lines and also in three Theileria annulata-infected cell lines. Cells expressing Tac antigen on their surface were found in all T. parva-infected cell lines tested whether these were of T- or B-cell origin. T cells expressing Tac antigen could be CD4- CD8-, CD4+ CD8-, CD4- CD8+, or CD4+ CD8+. Tac antigen expression was observed both in cultures which had been maintained in the laboratory for several years and in transformed cell lines which had recently been established by infection of lymphocytes in vitro with T. parva. Northern (RNA) blot analysis demonstrated Tac antigen transcripts in RNA isolated from all T. parva-infected cell lines. Three T. annulata-infected cell lines which were not of T-cell origin were also tested. Two of them expressed Tac antigen on their surface. Abundant Tac antigen mRNA was detected in these T. annulata-infected cell lines, but only trace amounts were demonstrated in the third cell line, which contained very few Tac antigen-expressing cells. In all cell lines tested, whether cloned or uncloned, a proportion of the cells did not express detectable levels of Tac antigen on their surface. This was also the case for a number of other leukocyte surface markers. In addition, we showed that the interleukin-2 receptors were biologically functional, because addition of recombinant interleukin-2 to cultures stimulated cell proliferation. Recombinant interleukin-2 treatment also resulted in increased amounts of steady-state Tac antigen mRNA. The relevance of interleukin-2 receptor expression on Theileria-infected cells is discussed. Images PMID:1979317

  13. The effect of interleukin-1 on iron metabolism in rats

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, Tatsumi; Yamagiwa, Akio; Nakamura, Kenichi (The First Department of Internal Medicine, Fukushima Medical College, Fukushima (Japan))

    1991-01-01

    The effect of interleukin-1 on iron metabolism in rats was evaluated. Plasma iron decreased from 184 +- 16 {mu}g/dl (mean +- SE) to 24 +- 12 at 6 hours after interleukin-1 intramuscular administration in non-fasting rats and 109 +- 6 {mu}g/dl to 12 +- 1 {mu}g/dl in fasting rats, which was significantly lower than in control rats. Ferrokinetic studies showed a more rapid disapperance rate and lower iron turnover in interleukin-1-injected rats. The release of iron from the mononuclear phagocyte system to plasma was studied at 3 h after interleukin-1 administration. Although the percent of radioactivity in plasma of the total injected dose was 3.2 +- 0.6% in interleukin-1, which was significantly lower than in the control rats (5.4 +- 0.6%) at 9 h after intravenous injection of {sup 59}Fe chondroitin ferrous sulfate, there was no differnece between the amount of {sup 59}Fe released from the mononuclear phagocyte system over the first 9 h in interleukin-1 and control rats. These data appear to imply that iron release is unimpaired but that, for some reason, there is an enhanced rate of clearance of the {sup 59}Fe once it has been released from the mononuclear phagocyte system into the plasma. (author).

  14. Disruption of δ-opioid receptor phosphorylation at threonine 161 attenuates morphine tolerance in rats with CFA-induced inflammatory hypersensitivity.

    Science.gov (United States)

    Chen, Hai-Jing; Xie, Wei-Yan; Hu, Fang; Zhang, Ying; Wang, Jun; Wang, Yun

    2012-04-01

    Our previous study identified Threonine 161 (Thr-161), located in the second intracellular loop of the δ-opioid receptor (DOR), as the only consensus phosphorylation site for cyclin-dependent kinase 5 (Cdk5). The aim of this study was to assess the function of DOR phosphorylation by Cdk5 in complete Freund's adjuvant (CFA)-induced inflammatory pain and morphine tolerance. Dorsal root ganglion (DRG) neurons of rats with CFA-induced inflammatory pain were acutely dissociated and the biotinylation method was used to explore the membrane localization of phosphorylated DOR at Thr-161 (pThr-161-DOR), and paw withdrawal latency was measured after intrathecal delivery of drugs or Tat-peptide, using a radiant heat stimulator in rats with CFA-induced inflammatory pain. Both the total amount and the surface localization of pThr-161-DOR were significantly enhanced in the ipsilateral DRG following CFA injection. Intrathecal delivery of the engineered Tat fusion-interefering peptide corresponding to the second intracellular loop of DOR (Tat-DOR-2L) increased inflammatory hypersensitivity, and inhibited DOR- but not µ-opioid receptor-mediated spinal analgesia in CFA-treated rats. However, intrathecal delivery of Tat-DOR-2L postponed morphine antinociceptive tolerance in rats with CFA-induced inflammatory pain. Phosphorylation of DOR at Thr-161 by Cdk5 attenuates hypersensitivity and potentiates morphine tolerance in rats with CFA-induced inflammatory pain, while disruption of the phosphorylation of DOR at Thr-161 attenuates morphine tolerance.

  15. Interleukin 9 and its receptor: an overview of structure and function.

    Science.gov (United States)

    Demoulin, J B; Renauld, J C

    1998-01-01

    Interleukin-9 (IL-9) is a multifunctional cytokine produced by activated TH2 clones in vitro and during TH2-like T cell responses in vivo. Although IL-9 was initially described as a T cell growth factor, its role in T cell responses is still unclear. While freshly isolated normal T cells do not respond to IL-9, this cytokine induces the proliferation of murine T cell lymphomas in vitro, and in vivo overexpression of IL-9 results in the development of thymic lymphomas. In the human, the existence of an IL-9 mediated autocrine loop has been suggested for some malignancies such as Hodgkin's disease. Various observations indicate that IL-9 is actively involved in mast cells responses by inducing the proliferation and differentiation of these cells. Other potential biological targets for IL-9 include B lymphocytes, and hematopoietic progenitors, for which higher responses were observed with foetal or transformed cells as compared to normal adult progenitors. The IL-9 receptor is a member of the hemopoietin receptor superfamily and interacts with the gamma chain of the IL-2 receptor for signaling. Signal transduction studies have stressed the role of the Jak-STAT pathway in various IL-9 bioactivities, whereas the 4PS/IRS2 adaptor protein might also play a significant role in IL-9 signaling.

  16. Effect of Interleukin 1b on rat thymus microenvironment

    Directory of Open Access Journals (Sweden)

    M Artico

    2009-12-01

    Full Text Available The effect of interleukin 1b on the thymus of control and chemically sympathectomized adult and aged rats was studied with the aim of assessing the importance of adrenergic nerve fibres (ANF in the regulation of some immunological functions.The whole thymus was removed from normal, sympathectomized (with the neurotoxin 6-OH-dopamine and treated (interleukin 1b rats. Thymic slices were stained with eosin orange (for the recognition of microanatomical details of the thymic microenvironment and with Bodian’s method for staining of nerve fibres. Histofluorescence microscopy was employed for staining ANF and immunofluorescence was used for detecting NPY-like immunoreactivity. All images were submitted to quantitative morphometrical analysis and statistical analysis of data. Moreover, the amount of proteins and noradrenaline was measured on thymic homogenates. The results indicate that in normal conditions the formation of the thymic nerve plexi in the rat is complex: the majority of ANF are destroyed after chemical sympathectomy with 6-OH-dopamine and do not change after treatment with interleukin 1b; on the contrary, treatment with interleukin 1b induces substantial changes in the fresh weight of the thymus, the thymic microenvironment, thymic nerve fibers, ANF, NPY-like positive nerve fibres, and on the total amount of proteins and noradrenaline in rat thymic tissue homogenates.Immunostimulation with interleukin 1b induces substantial changes in the whole thymus, in its microenvironment and in ANF and NPY-like nerve fibres. After chemical sympathectomy, no significant immune response was evoked by interleukin 1b, since the majority of ANF was destroyed by chemical sympathectomy.

  17. Increased circulating interleukin-8 in patients with resistance to thyroid hormone receptor α

    Directory of Open Access Journals (Sweden)

    Anne H van der Spek

    2017-11-01

    Full Text Available Innate immune cells have recently been identified as novel thyroid hormone (TH target cells in which intracellular TH levels appear to play an important functional role. The possible involvement of TH receptor alpha (TRα, which is the predominant TR in these cells, has not been studied to date. Studies in TRα0/0 mice suggest a role for this receptor in innate immune function. The aim of this study was to determine whether TRα affects the human innate immune response. We assessed circulating interleukin-8 concentrations in a cohort of 8 patients with resistance to TH due to a mutation of TRα (RTHα and compared these results to healthy controls. In addition, we measured neutrophil and macrophage function in one of these RTHα patients (mutation D211G. Circulating interleukin-8 levels were elevated in 7 out of 8 RTHα patients compared to controls. These patients harbor different mutations, suggesting that this is a general feature of the syndrome of RTHα. Neutrophil spontaneous apoptosis, bacterial killing, NAPDH oxidase activity and chemotaxis were unaltered in cells derived from the RTHαD211G patient. RTHα macrophage phagocytosis and cytokine induction after LPS treatment were similar to results from control cells. The D211G mutation did not result in clinically relevant impairment of neutrophil or pro-inflammatory macrophage function. As elevated circulating IL-8 is also observed in hyperthyroidism, this observation could be due to the high-normal to high levels of circulating T3 found in patients with RTHα.

  18. Angiotensin II modulates interleukin-1β-induced inflammatory gene expression in vascular smooth muscle cells via interfering with ERK-NF-κB crosstalk

    International Nuclear Information System (INIS)

    Xu, Shanqin; Zhi, Hui; Hou, Xiuyun; Jiang, Bingbing

    2011-01-01

    Highlights: → We examine how angiotensin II modulates ERK-NF-κB crosstalk and gene expression. → Angiotensin II suppresses IL-1β-induced prolonged ERK and NF-κB activation. → ERK-RSK1 signaling is required for IL-1β-induced prolonged NF-κB activation. → Angiotensin II modulates NF-κB responsive genes via regulating ERK-NF-κB crosstalk. → ERK-NF-κB crosstalk is a novel mechanism regulating inflammatory gene expression. -- Abstract: Angiotensin II is implicated in cardiovascular diseases, which is associated with a role in increasing vascular inflammation. The present study investigated how angiotensin II modulates vascular inflammatory signaling and expression of inducible nitric oxide synthase (iNOS) and vascular cell adhesion molecule (VCAM)-1. In cultured rat aortic vascular smooth muscle cells (VSMCs), angiotensin II suppressed interleukin-1β-induced prolonged phosphorylation of extracellular signal-regulated kinase (ERK) and ribosomal S6 kinase (RSK)-1, and nuclear translocation of nuclear factor (NF)-κB, leading to decreased iNOS but enhanced VCAM-1 expression, associated with an up-regulation of mitogen-activated protein kinase phosphatase-1 expression. Knock-down of RSK1 selectively down regulated interleukin-1β-induced iNOS expression without influencing VCAM-1 expression. In vivo experiments showed that interleukin-1β, iNOS, and VCAM-1 expression were detectable in the aortic arches of both wild-type and apolipoprotein E-deficient (ApoE -/- ) mice. VCAM-1 and iNOS expression were higher in ApoE -/- than in wild type mouse aortic arches. Angiotensin II infusion (3.2 mg/kg/day, for 6 days, via subcutaneous osmotic pump) in ApoE -/- mice enhanced endothelial and adventitial VCAM-1 and iNOS expression, but reduced medial smooth muscle iNOS expression associated with reduced phosphorylation of ERK and RSK-1. These results indicate that angiotensin II can differentially modulate inflammatory gene expression in aortic smooth muscle cells

  19. Investigation of the role of interleukin-1 receptor antagonist VNTR variant on the Behçet’s disease

    Science.gov (United States)

    Dursun, Gül; Demir, Helin Deniz; Karakuş, Nevin; Demir, Osman; Yiğit, Serbülent

    2018-01-01

    Objective Behçet’s disease (BD), a chronic multisystem inflammatory disorder, is mainly characterized by relapsing periods of a wide range of clinical symptoms. Several cytokine genes may play important roles in the pathogenesis of BD. Therefore, interleukin-1 receptor antagonist (IL-1Ra) gene 86bp variable number tandem repeat (VNTR) variant was investigated in patients with BD in a Turkish population. Methods One hundred nine patients (60 females, 49 males; the mean age±standard deviation [SD] was 36.56±9.571 years) with BD and one hundred healthy individuals (54 females, 46 males; the mean age±SD was 36.64±2.294 years) were examined in the study. For genotyping, polymerase chain reaction-restriction fragment length polymorphism analysis was employed. Data were analyzed using Statistical Package for Social Sciences (SPSS) 22.0 (IBM Corp.; Armonk, NY, USA) (p0.05). The frequency of the a1/a1, a1/a2 genotypes and a1, a2 alleles were the most common both in patients and healthy controls (p=0.37, p=0.26, and p=0.53, respectively). Also, no statistically significant difference was found between the IL-1Ra VNTR variant genotypes and clinical characteristics (p>0.05). Conclusion The results of this study do not support an association between the IL-1Ra VNTR variant and the risk of BD in a Turkish population. However, further studies of this variant with larger sample sizes and different ethnicities are required for confirmation. PMID:29657871

  20. Characterization of phosphorylated beta-adrenergic receptors from desensitized turkey erythrocytes

    International Nuclear Information System (INIS)

    Rebar, R.; Crooke, S.T.; Stadel, J.M.

    1986-01-01

    Catecholamine-induced desensitization of turkey erythrocyte (TE) adenylate cyclase results in a 40-50 percent decrease in agonist stimulated cyclase activity. Desensitization is accompanied by decreased mobility on SDS-PAGE of beta-adrenergic receptor (BAR) proteins photoaffinity labeled with [ 125 I]-p-azidobenzylcarazolol compared to control. Using a low crosslinked gel, the M/sub r/ = 42,000 band of BAR from desensitized TE was further resolved into a doublet compared to a single M/sub r/ = 38,000 band for control. The formation of the doublet appears to correlate with the amount of adenylate cyclase desensitization. Preincubating TE for 20 hr at 37 0 C with 32 P-/sub i/ labels BAR. 32 P-BAR was partially purified by affinity chromatography over alprenolol-Sepharose. Limited digest peptide maps of 32 P-BAR using papain identified a unique peptide (M/sub r/ = 2800) from BAR of desensitized TE which was absent in control. This unique 32 P-peptide was found only in the upper band of the doublet of BAR from desensitized TE. These data indicate that BAR is not uniformly phosphorylated following agonist-induced desensitization of TE and identify a peptide of BAR which is a site of phosphorylation correlating with desensitization of TE adenylate cyclase

  1. CSF-1 Receptor Signaling in Myeloid Cells

    Science.gov (United States)

    Stanley, E. Richard; Chitu, Violeta

    2014-01-01

    The CSF-1 receptor (CSF-1R) is activated by the homodimeric growth factors colony-stimulating factor-1 (CSF-1) and interleukin-34 (IL-34). It plays important roles in development and in innate immunity by regulating the development of most tissue macrophages and osteoclasts, of Langerhans cells of the skin, of Paneth cells of the small intestine, and of brain microglia. It also regulates the differentiation of neural progenitor cells and controls functions of oocytes and trophoblastic cells in the female reproductive tract. Owing to this broad tissue expression pattern, it plays a central role in neoplastic, inflammatory, and neurological diseases. In this review we summarize the evolution, structure, and regulation of expression of the CSF-1R gene. We review, the structures of CSF-1, IL-34, and the CSF-1R and the mechanism of ligand binding to and activation of the receptor. We further describe the pathways regulating macrophage survival, proliferation, differentiation, and chemotaxis downstream from the CSF-1R. PMID:24890514

  2. Synaptotagmin-7 phosphorylation mediates GLP-1-dependent potentiation of insulin secretion from β-cells

    DEFF Research Database (Denmark)

    Wu, Bingbing; Wei, Shunhui; Petersen, Natalia

    2015-01-01

    Glucose stimulates insulin secretion from β-cells by increasing intracellular Ca(2+). Ca(2+) then binds to synaptotagmin-7 as a major Ca(2+) sensor for exocytosis, triggering secretory granule fusion and insulin secretion. In type-2 diabetes, insulin secretion is impaired; this impairment...... is ameliorated by glucagon-like peptide-1 (GLP-1) or by GLP-1 receptor agonists, which improve glucose homeostasis. However, the mechanism by which GLP-1 receptor agonists boost insulin secretion remains unclear. Here, we report that GLP-1 stimulates protein kinase A (PKA)-dependent phosphorylation...... of synaptotagmin-7 at serine-103, which enhances glucose- and Ca(2+)-stimulated insulin secretion and accounts for the improvement of glucose homeostasis by GLP-1. A phospho-mimetic synaptotagmin-7 mutant enhances Ca(2+)-triggered exocytosis, whereas a phospho-inactive synaptotagmin-7 mutant disrupts GLP-1...

  3. PTPRZ1 regulates calmodulin phosphorylation and tumor progression in small-cell lung carcinoma

    International Nuclear Information System (INIS)

    Makinoshima, Hideki; Ishii, Genichiro; Kojima, Motohiro; Fujii, Satoshi; Higuchi, Youichi; Kuwata, Takeshi; Ochiai, Atsushi

    2012-01-01

    Small-cell lung carcinoma (SCLC) is a neuroendocrine tumor subtype and comprises approximately 15% of lung cancers. Because SCLC is still a disease with a poor prognosis and limited treatment options, there is an urgent need to develop targeted molecular agents for this disease. We screened 20 cell lines from a variety of pathological phenotypes established from different organs by RT-PCR. Paraffin-embedded tissue from 252 primary tumors was examined for PTPRZ1 expression using immunohistochemistry. shRNA mediated PTPRZ1 down-regulation was used to study impact on tyrosine phosphorylation and in vivo tumor progression in SCLC cell lines. Here we show that PTPRZ1, a member of the protein tyrosine- phosphatase receptor (PTPR) family, is highly expressed in SCLC cell lines and specifically exists in human neuroendocrine tumor (NET) tissues. We also demonstrate that binding of the ligand of PTPRZ1, pleiotrophin (PTN), activates the PTN/PTPRZ1 signaling pathway to induce tyrosine phosphorylation of calmodulin (CaM) in SCLC cells, suggesting that PTPRZ1 is a regulator of tyrosine phosphorylation in SCLC cells. Furthermore, we found that PTPRZ1 actually has an important oncogenic role in tumor progression in the murine xenograft model. PTPRZ1 was highly expressed in human NET tissues and PTPRZ1 is an oncogenic tyrosine phosphatase in SCLCs. These results imply that a new signaling pathway involving PTPRZ1 could be a feasible target for treatment of NETs

  4. Interleukin 17 receptor A modulates monocyte subsets and macrophage generation in vivo.

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    Shuwang Ge

    Full Text Available Interleukin (IL-17A signaling via Interleukin 17 receptor A (Il17ra contributes to the inflammatory host response by inducing recruitment of innate immune cells, but also plays a role in homeostatic neutrophilic granulocyte regulation. Monocytes, the other main innate immune cell, have a longer life span and can pursue multiple differentiation pathways towards tissue macrophages. Monocytes are divided into two subpopulations by expression of the Ly6C/Gr1 surface marker in mice. We here investigated the role of Il17ra in monocyte homeostasis and macrophage generation. In Il17ra(-/- and in mixed bone marrow chimeric wt/Il17ra(-/- mice, the concentrations of circulating Il17ra(-/- Gr1(low monocytes were significantly decreased compared to wt cells. Pulmonary, splenic and resident peritoneal Il17ra(-/- macrophages were significantly fewer than of wt origin. Bone marrow progenitor and monocyte numbers were equal, but the proportion of Il17ra(-/- Gr1(low monocytes was already decreased at bone marrow level. After monocyte depletion, initial Gr1(high and Gr1(low monocyte regeneration of Il17ra(-/- and wt cells was very similar. However, Il17ra(-/- Gr1(low counts were not sustained. After labeling with either fluorescent beads or BrdU, Il17ra(-/- Gr1(high monocyte transition to Gr1(low cells was not detectable unlike wt cells. Monocyte recruitment in acute peritonitis, which is known to be largely due to Gr1(high cell migration, was unaffected in an identical environment. Unilateral ureteral obstruction induces a less acute inflammatory and fibrotic kidney injury. Compared to wt cells in the same environment, Il17ra(-/- macrophage accumulation in the kidney was decreased. In the absence of Il17ra on all myeloid cells, renal fibrosis was significantly attenuated. Our data show that Il17ra modulates Gr1(low monocyte counts and suggest defective Gr1(high to Gr1(low monocyte transition as an underlying mechanism. Lack of Il17ra altered homeostatic tissue

  5. A Polysaccharide Virulence Factor from Aspergillus fumigatus Elicits Anti-inflammatory Effects through Induction of Interleukin-1 Receptor Antagonist

    Science.gov (United States)

    Gresnigt, Mark S.; Bozza, Silvia; Becker, Katharina L.; Joosten, Leo A. B.; Abdollahi-Roodsaz, Shahla; van der Berg, Wim B.; Dinarello, Charles A.; Netea, Mihai G.; Fontaine, Thierry; De Luca, Antonella; Moretti, Silvia; Romani, Luigina; Latge, Jean-Paul; van de Veerdonk, Frank L.

    2014-01-01

    The galactosaminogalactan (GAG) is a cell wall component of Aspergillus fumigatus that has potent anti-inflammatory effects in mice. However, the mechanisms responsible for the anti-inflammatory property of GAG remain to be elucidated. In the present study we used in vitro PBMC stimulation assays to demonstrate, that GAG inhibits proinflammatory T-helper (Th)1 and Th17 cytokine production in human PBMCs by inducing Interleukin-1 receptor antagonist (IL-1Ra), a potent anti-inflammatory cytokine that blocks IL-1 signalling. GAG cannot suppress human T-helper cytokine production in the presence of neutralizing antibodies against IL-1Ra. In a mouse model of invasive aspergillosis, GAG induces IL-1Ra in vivo, and the increased susceptibility to invasive aspergillosis in the presence of GAG in wild type mice is not observed in mice deficient for IL-1Ra. Additionally, we demonstrate that the capacity of GAG to induce IL-1Ra could also be used for treatment of inflammatory diseases, as GAG was able to reduce severity of an experimental model of allergic aspergillosis, and in a murine DSS-induced colitis model. In the setting of invasive aspergillosis, GAG has a significant immunomodulatory function by inducing IL-1Ra and notably IL-1Ra knockout mice are completely protected to invasive pulmonary aspergillosis. This opens new treatment strategies that target IL-1Ra in the setting of acute invasive fungal infection. However, the observation that GAG can also protect mice from allergy and colitis makes GAG or a derivative structure of GAG a potential treatment compound for IL-1 driven inflammatory diseases. PMID:24603878

  6. Thyrocyte-interleukin-1 interactions

    DEFF Research Database (Denmark)

    Rasmussen, A K; Bendtzen, K; Feldt-Rasmussen, U

    2000-01-01

    Autoimmune thyroid disease is the most common organ-specific autoimmune disease and is a very common cause of thyroid dysfunction such as autoimmune hypothyroidism, Graves' disease and postpartum thyroiditis. The thyroid gland from patients with autoimmune thyroid disease is morphologically...... characterized by massive infiltration of lymphoid cells. The interleukin-1 (IL-1) family of molecules is together with other cytokines an integral component of the complex intercellular communication required to mount and control an immune response. IL-1alpha/beta in moderate and high concentrations reversibly...

  7. Tyrosine phosphorylation of LRP6 by Src and Fer inhibits Wnt/β-catenin signalling

    Science.gov (United States)

    Chen, Qing; Su, Yi; Wesslowski, Janine; Hagemann, Anja I; Ramialison, Mirana; Wittbrodt, Joachim; Scholpp, Steffen; Davidson, Gary

    2014-01-01

    Low-density lipoprotein receptor-related proteins 5 and 6 (LRP5/6) function as transmembrane receptors to transduce Wnt signals. A key mechanism for signalling is Wnt-induced serine/threonine phosphorylation at conserved PPPSPxS motifs in the LRP6 cytoplasmic domain, which promotes pathway activation. Conserved tyrosine residues are positioned close to all PPPSPxS motifs, which suggests they have a functional significance. Using a cell culture-based cDNA expression screen, we identified the non-receptor tyrosine kinases Src and Fer as novel LRP6 modifiers. Both Src and Fer associate with LRP6 and phosphorylate LRP6 directly. In contrast to the known PPPSPxS Ser/Thr kinases, tyrosine phosphorylation by Src and Fer negatively regulates LRP6-Wnt signalling. Epistatically, they function upstream of β-catenin to inhibit signalling and in agreement with a negative role in regulating LRP6, MEF cells lacking these kinases show enhanced Wnt signalling. Wnt3a treatment of cells enhances tyrosine phosphorylation of endogenous LRP6 and, mechanistically, Src reduces cell surface LRP6 levels and disrupts LRP6 signalosome formation. Interestingly, CK1γ inhibits Fer-induced LRP6 phosphorylation, suggesting a mechanism whereby CK1γ acts to de-represses inhibitory LRP6 tyrosine phosphorylation. We propose that LRP6 tyrosine phosphorylation by Src and Fer serves a negative regulatory function to prevent over-activation of Wnt signalling at the level of the Wnt receptor, LRP6. Subject Categories Membrane & Intracellular Transport; Post-translational Modifications, Proteolysis & Proteomics PMID:25391905

  8. Effect of interleukin-2 on cell proliferation, sister-chromatid exchange induction, and nuclear stress protein phosphorylation in PHA-stimulated Fischer 344 rat spleen lymphocytes: Modulation by 2-mercaptoethanol

    Energy Technology Data Exchange (ETDEWEB)

    Morris, S.M.; Aidoo, A.; Domon, O.E.; McGarrity, L.J.; Kodell, R.L.; Schol, H.M.; Hinson, W.G.; Pipkin, J.L.; Casciano, D.A. (National Center for Toxicological Research, Jefferson, AR (USA))

    1990-01-01

    The effect of interleukin-2 (IL-2) on cell proliferation, sister-chromatid exchange (SCE) frequency, and the phosphorylation of nuclear stress proteins was evaluated in phytohemagglutinin (PHA)-stimulated spleen lymphocytes isolated from Fischer 344 rats. In addition, the ability of 2-mercaptoethanol (2-ME) to modulate the induction of these biological responses was characterized. Cell proliferation, as measured by the mitotic index, increased significantly. The average generation time (AGT) did not respond to IL-2 in a concentration-dependent manner and decreased significantly. The number of SCE increased significantly from control frequencies, to frequencies of 18.5 to 21.5 SCE per cell as the concentration of IL-2 in the culture medium increased to 50 half-maximal units per ml. A reduction in SCE frequency was observed when cells were cultured with 20 {mu}M 2-ME and IL-2 compared to IL-2 alone. Three nuclear proteins, with relative molecular masses of approximately 13,000-18,000, 20,000, and 80,000, were phosphorylated in IL-2-exposed G{sub 1}-phase nuclei. Elicitation of these nuclear proteins in IL-2-exposed cells was not affected by exposure to 2-ME.

  9. Sustained Interleukin-1β Exposure Modulates Multiple Steps in Glucocorticoid Receptor Signaling, Promoting Split-Resistance to the Transactivation of Prominent Anti-Inflammatory Genes by Glucocorticoids

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    Pedro Escoll

    2015-01-01

    Full Text Available Clinical treatment with glucocorticoids (GC can be complicated by cytokine-induced glucocorticoid low-responsiveness (GC-resistance, GCR, a condition associated with a homogeneous reduction in the expression of GC-receptor- (GR- driven anti-inflammatory genes. However, GR level and phosphorylation changes modify the expression of individual GR-responsive genes differently. As sustained IL-1β exposure is key in the pathogenesis of several major diseases with prevalent GCR, we examined GR signaling and the mRNA expression of six GR-driven genes in cells cultured in IL-1β and afterwards challenged with GC. After a GC challenge, sustained IL-1β exposure reduced the cytoplasmic GR level, GRSer203 and GRSer211 phosphorylation, and GR nuclear translocation and led to selective GCR in the expression of the studied genes. Compared to GC alone, in a broad range of GC doses plus sustained IL-1β, FKBP51 mRNA expression was reduced by 1/3, TTP by 2/3, and IRF8 was completely knocked down. In contrast, high GC doses did not change the expression of GILZ and DUSP1, while IGFBP1 was increased by 5-fold. These effects were cytokine-selective, IL-1β dose- and IL-1R1-dependent. The integrated gain and loss of gene functions in the “split GCR” model may provide target cells with a survival advantage by conferring resistance to apoptosis, chemotherapy, and GC.

  10. Phosphorylation regulates SIRT1 function.

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    Tsutomu Sasaki

    Full Text Available BACKGROUND: SIR2 is an NAD(+-dependent deacetylase [1]-[3] implicated in the regulation of lifespan in species as diverse as yeast [4], worms [5], and flies [6]. We previously reported that the level of SIRT1, the mammalian homologue of SIR2 [7], [8], is coupled to the level of mitotic activity in cells both in vitro and in vivo[9]. Cells from long-lived mice maintained SIRT1 levels of young mice in tissues that undergo continuous cell replacement by proliferating stem cells. Changes in SIRT1 protein level were not associated with changes in mRNA level, suggesting that SIRT1 could be regulated post-transcriptionally. However, other than a recent report on sumoylation [10] and identification of SIRT1 as a nuclear phospho-protein by mass spectrometry [11], post-translational modifications of this important protein have not been reported. METHODOLOGY/PRINCIPAL FINDINGS: We identified 13 residues in SIRT1 that are phosphorylated in vivo using mass spectrometry. Dephosphorylation by phosphatases in vitro resulted in decreased NAD(+-dependent deacetylase activity. We identified cyclinB/Cdk1 as a cell cycle-dependent kinase that forms a complex with and phosphorylates SIRT1. Mutation of two residues phosphorylated by Cyclin B/Cdk1 (threonine 530 and serine 540 disturbs normal cell cycle progression and fails to rescue proliferation defects in SIRT1-deficient cells [12], [13]. CONCLUSIONS/SIGNIFICANCE: Pharmacological manipulation of SIRT1 activity is currently being tested as a means of extending lifespan in mammals. Treatment of obese mice with resveratrol, a pharmacological activator of SIRT1, modestly but significantly improved longevity and, perhaps more importantly, offered some protection against the development of type 2 diabetes mellitus and metabolic syndrome [14]-[16]. Understanding the endogenous mechanisms that regulate the level and activity of SIRT1, therefore, has obvious relevance to human health and disease. Our results identify

  11. Uncaria rhynchophylla inhibits the production of nitric oxide and interleukin-1β through blocking nuclear factor κB, Akt, and mitogen-activated protein kinase activation in macrophages.

    Science.gov (United States)

    Kim, Ji-Hee; Bae, Chang Hwan; Park, Sun Young; Lee, Sang Joon; Kim, YoungHee

    2010-10-01

    The stems with hook of Uncaria rhynchophylla have been used in traditional medicine as an antipyretic, antihypertensive, and anticonvulsant in China and Korea. In this study, we investigated the mechanism responsible for anti-inflammatory effects of U. rhynchophylla in RAW 264.7 macrophages. The aqueous extract of U. rhynchophylla inhibited lipopolysaccharide (LPS)-induced nitric oxide (NO) and interleukin (IL)-1β secretion as well as inducible NO synthase (iNOS) expression, without affecting cell viability. Furthermore, U. rhynchophylla suppressed LPS-induced nuclear factor κB (NF-κB) activation, phosphorylation, and degradation of inhibitory protein IκB (IκB)-α, phosphorylation of Akt, extracellular signal-regulated kinase 1/2, p38 kinase, and c-Jun N-terminal kinase. These results suggest that U. rhynchophylla has the inhibitory effects on LPS-induced NO and IL-1β production in macrophages through blockade in the phosphorylation of Akt and mitogen-activated protein kinases, following IκB-α degradation and NF-κB activation.

  12. Academic Stress Influences Periodontal Health Condition and Interleukin-1 beta Level

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    Sandra O. Kuswandani

    2014-10-01

    Full Text Available Stress is a risk factor for periodontal disease, causing increase levels of interleukin-1 beta that involve in periodontal destruction. Objective: To analyze the relationship between academic stress in residency program students conditions and levels of interleukin-1 beta in gingival crevicular fluid. Methods: Thirty eight subjects filled the questionnaire of Graduate Dental Environtmental Stress (GDES, periodontal examination and samples of gingival crevicular fluid were tested for interleukin-1 beta with the Enzyme-linked Immunosorbent Assay (ELISA test. Results: There were significant differences between academic stress to periodontal tissue in oral hygiene (p=0.038, bleeding on probing index (p=0.02, but no significant differences in pocket depth and loss of attachment (p=0.972. There were significant differences between academic stress to levels of interleukin-1 beta (p=0.03, but no significant differences between levels of interleukin-1 beta to periodontal tissue in oral hygiene (p=0.465, bleeding on probing index (p=0.826, pocket depth (p=0.968, and loss of attachment (p=0.968. Conclusion: Academic stress influences the periodontal risk factor and level of interleukin-1 beta.

  13. Cloning and expression of porcine Colony Stimulating Factor-1 (CSF-1) and Colony Stimulating Factor-1 Receptor (CSF-1R) and analysis of the species specificity of stimulation by CSF-1 and Interleukin 34

    Science.gov (United States)

    Gow, Deborah J.; Garceau, Valerie; Kapetanovic, Ronan; Sester, David P.; Fici, Greg J.; Shelly, John A.; Wilson, Thomas L.; Hume, David A.

    2012-01-01

    Macrophage Colony Stimulating Factor (CSF-1) controls the survival, differentiation and proliferation of cells of the mononuclear phagocyte system. A second ligand for the CSF-1R, Interleukin 34 (IL-34), has been described, but its physiological role is not yet known. The domestic pig provides an alternative to traditional rodent models for evaluating potential therapeutic applications of CSF-1R agonists and antagonists. To enable such studies, we cloned and expressed active pig CSF-1. To provide a bioassay, pig CSF-1R was expressed in the factor-dependent Ba/F3 cell line. On this transfected cell line, recombinant porcine CSF-1 and human CSF-1 had identical activity. Mouse CSF-1 does not interact with the human CSF-1 receptor but was active on pig. By contrast, porcine CSF-1 was active on mouse, human, cat and dog cells. IL-34 was previously shown to be species-specific, with mouse and human proteins demonstrating limited cross-species activity. The pig CSF-1R was equally responsive to both mouse and human IL-34. Based upon the published crystal structures of CSF-1/CSF-1R and IL34/CSF-1R complexes, we discuss the molecular basis for the species specificity. PMID:22974529

  14. Upregulation of Shiga toxin receptor CD77/Gb3 and interleukin-1β expression in the brain of EHEC patients with hemolytic uremic syndrome and neurologic symptoms.

    Science.gov (United States)

    Hagel, Christian; Krasemann, Susanne; Löffler, Judith; Püschel, Klaus; Magnus, Tim; Glatzel, Markus

    2015-03-01

    In 2011, a large outbreak of Shiga toxin-producing enterohemorrhagic Escherichia coli (EHEC) infections occurred in northern Germany, which mainly affected adults. Out of 3842 patients, 104 experienced a complicated course comprising hemolytic uremic syndrome and neurological complications, including cognitive impairment, aphasia, seizures and coma. T2 hyperintensities on magnet resonance imaging (MRI) bilateral in the thalami and in the dorsal pons were found suggestive of a metabolic toxic effect. Five of the 104 patients died because of toxic heart failure. In the present study, the post-mortem neuropathological findings of the five EHEC patients are described. Histological investigation of 13 brain regions (frontal, temporal, occipital cortex, corpora mammillaria, thalamus, frontal operculum, corona radiata, gyrus angularis, pons, medulla oblongata, cerebellar vermis and cerebellar hemisphere) showed no thrombosis, ischemic changes or fresh infarctions. Further, no changes were found in electron microscopy. In comparison with five age-matched controls, slightly increased activation of microglia and a higher neuronal expression of interleukin-1β and of Shiga toxin receptor CD77/globotriaosylceramide 3 was observed. The findings were confirmed by Western blot analyses. It is suggested that CD77/globotriaosylceramide upregulation may be a consequence to Shiga toxin exposure, whereas increased interleukin-1β expression may point to activation of inflammatory cascades. © 2014 International Society of Neuropathology.

  15. Resveratrol inhibits PDGF receptor mitogenic signaling in mesangial cells: role of PTP1B

    Science.gov (United States)

    Venkatesan, Balachandar; Ghosh-Choudhury, Nandini; Das, Falguni; Mahimainathan, Lenin; Kamat, Amrita; Kasinath, Balakuntalam S.; Abboud, Hanna E.; Choudhury, Goutam Ghosh

    2008-01-01

    Mesangioproliferative glomerulonephritis is associated with overactive PDGF receptor signal transduction. We show that the phytoalexin resveratrol dose dependently inhibits PDGF-induced DNA synthesis in mesangial cells with an IC50 of 10 μM without inducing apoptosis. Remarkably, the increased SIRT1 deacetylase activity induced by resveratrol was not necessary for this inhibitory effect. Resveratrol significantly blocked PDGF-stimulated c-Src and Akt kinase activation, resulting in reduced cyclin D1 expression and attenuated pRb phosphorylation and cyclin-dependent kinase-2 (CDK2) activity. Furthermore, resveratrol inhibited PDGFR phosphorylation at the PI 3 kinase and Grb-2 binding sites tyrosine-751 and tyrosine-716, respectively. This deficiency in PDGFR phosphorylation resulted in significant inhibition of PI 3 kinase and Erk1/2 MAPK activity. Interestingly, resveratrol increased the activity of protein tyrosine phosphatase PTP1B, which dephosphorylates PDGF-stimulated phosphorylation at tyrosine-751 and tyrosine-716 on PDGFR with concomitant reduction in Akt and Erk1/2 kinase activity. PTP1B significantly inhibited PDGF-induced DNA synthesis without inducing apoptosis. These results for the first time provide evidence that the stilbene resveratrol targets PTP1B to inhibit PDGFR mitogenic signaling.—Venkatesan, B., Ghosh-Choudhury, N., Das, F., Mahimainathan, L., Kamat, A., Kasinath, B. S., Abboud, H. E., Choudhury, G. G. Resveratrol inhibits PDGF receptor mitogenic signaling in mesangial cells: role of PTP1B. PMID:18567737

  16. Interleukin-6-receptor polymorphisms rs12083537, rs2228145, and rs4329505 as predictors of response to tocilizumab in rheumatoid arthritis

    DEFF Research Database (Denmark)

    Enevold, Christian; Baslund, Bo; Linde, Louise

    2014-01-01

    Tocilizumab (TCZ), a monoclonal antibody targeting the human interleukin-6-receptor (IL-6R), is indicated for the treatment of rheumatoid arthritis (RA). We examined whether three IL6R single-nucleotide polymorphisms rs12083537, rs2228145 (formerly rs8192284), and rs4329505 with previously report...

  17. Dopaminergic and cholinergic regulation of Fyn tyrosine kinase phosphorylation in the rat striatum in vivo.

    Science.gov (United States)

    Mao, Li-Min; Wang, John Q

    2015-12-01

    Src and Fyn are two Src family kinase (SFK) members that are expressed in mammalian brains and play important roles in the regulation of a variety of neuronal and synaptic substrates. Here we investigated the responsiveness of these SFKs to changing dopamine receptor signals in dopamine responsive regions of adult rat brains in vivo. Pharmacological activation of dopamine D1 receptors (D1Rs) by a systemic injection of the selective agonist SKF81297 increased phosphorylation of SFKs at a conserved and activation-associated autophosphorylation site (Y416) in the striatum, indicating activation of SFKs following SKF81297 injection. The dopamine D2 receptor (D2R) agonist quinpirole had no effect. Blockade of D1Rs with an antagonist SCH23390 did not alter striatal Y416 phosphorylation, while the D2R antagonist eticlopride elevated it. Between Src and Fyn, SKF81297 seemed to preferentially facilitate Fyn phosphorylation. Activation of muscarinic acetylcholine M4 receptors (M4Rs) with a positive allosteric modulator VU0152100 suppressed SFK Y416 responses to SKF81297. Additionally, SKF81297 induced a correlated increase in phosphorylation of N-methyl-D-aspartate (NMDA) receptor GluN2B subunits at a Fyn site (Y1472), which was attenuated by VU0152100. SKF81297 also enhanced synaptic recruitments of active Fyn and GluN1/GluN2B-containing NMDA receptors. These data demonstrate that D1Rs regulate Fyn and downstream NMDA receptors in striatal neurons in vivo. Acetylcholine through activating M4Rs inhibits Fyn and NMDA receptors in their sensitivity to D1R signaling. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. CB1 receptor-mediated signaling underlies the hippocampal synaptic, learning, and memory deficits following treatment with JWH-081, a new component of spice/K2 preparations.

    Science.gov (United States)

    Basavarajappa, Balapal S; Subbanna, Shivakumar

    2014-02-01

    Recently, synthetic cannabinoids have been sprayed onto plant material, which is subsequently packaged and sold as "Spice" or "K2" to mimic the effects of marijuana. A recent report identified several synthetic additives in samples of "Spice/K2", including JWH-081, a synthetic ligand for the cannabinoid receptor 1 (CB1). The deleterious effects of JWH-081 on brain function are not known, particularly on CB1 signaling, synaptic plasticity, learning and memory. Here, we evaluated the effects of JWH-081 on pCaMKIV, pCREB, and pERK1/2 signaling events followed by long-term potentiation (LTP), hippocampal-dependent learning and memory tasks using CB1 receptor wild-type (WT) and knockout (KO) mice. Acute administration of JWH-081 impaired CaMKIV phosphorylation in a dose-dependent manner, whereas inhibition of CREB phosphorylation in CB1 receptor WT mice was observed only at higher dose of JWH-081 (1.25 mg/kg). JWH-081 at higher dose impaired CaMKIV and CREB phosphorylation in a time-dependent manner in CB1 receptor WT mice but not in KO mice and failed to alter ERK1/2 phosphorylation. In addition, SR treated or CB1 receptor KO mice have a lower pCaMKIV/CaMKIV ratio and higher pCREB/CREB ratio compared with vehicle or WT littermates. In hippocampal slices, JWH-081 impaired LTP in CB1 receptor WT but not in KO littermates. Furthermore, JWH-081 at higher dose impaired object recognition, spontaneous alternation and spatial memory on the Y-maze in CB1 receptor WT mice but not in KO mice. Collectively our findings suggest that deleterious effects of JWH-081 on hippocampal function involves CB1 receptor mediated impairments in CaMKIV and CREB phosphorylation, LTP, learning and memory in mice. © 2013 Wiley Periodicals, Inc.

  19. Interleukin-1 antagonists in the treatment of autoinflammatory syndromes, including cryopyrin-associated periodic syndrome

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    Pierre Quartier

    2011-01-01

    Full Text Available Pierre QuartierUnité d'Immunologie-Hématologie et Rhumatologie pédiatriques, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, FranceAbstract: Cryopyrin-associated periodic syndrome (CAPS include a group of rare autoinflammatory disorders, the spectrum of which ranges from the mildest form, ie, familial cold autoinflammatory syndrome to more severe phenotypes, ie, Muckle-Wells syndrome, and chronic infantile neurological cutaneous and articular syndrome, also known as neonatal-onset multisystem inflammatory disease. Three interleukin (IL-1 antagonists have been tested in adults and children with CAPS, ie, anakinra, a recombinant homolog of the human IL-1 receptor antagonist; rilonacept, a fusion protein comprising the extracellular domains of IL-1 receptor I and the IL-1 adaptor protein, IL-1RAcP, attached to a human immunoglobulin G molecule; and canakinumab, the anti-IL-1β monoclonal antibody. Following rapid clinical development, rilonacept and canakinumab were approved by both the US Food and Drug Administration and the European Medicines Agency for use in adults and children. This review describes how the study of CAPS has helped us to understand better the way the innate immune system works, the pathogenesis of autoinflammatory syndromes, and the key role of IL-1. It also reviews the effects of IL-1 blockade in CAPS and other disorders, in particular systemic juvenile idiopathic arthritis, adult-onset Still's disease, and gout. Finally, this review covers some issues addressed by very recent and ongoing work regarding treatment indications, from orphan diseases to common disorders, continuous versus intermittent treatment, the pharmacokinetics, pharmacodynamics, and optimal dosages of the different drugs, as well as the need for Phase IV trials, exhaustive registries, and long-term follow-up of several patient cohorts.Keywords: inflammation, interleukin-1, cytokines, treatment

  20. Nonstructural 5A Protein of Hepatitis C Virus Interferes with Toll-Like Receptor Signaling and Suppresses the Interferon Response in Mouse Liver.

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    Takeya Tsutsumi

    Full Text Available The hepatitis C virus nonstructural protein NS5A is involved in resistance to the host immune response, as well as the viral lifecycle such as replication and maturation. Here, we established transgenic mice expressing NS5A protein in the liver and examined innate immune responses against lipopolysaccharide (LPS in vivo. Intrahepatic gene expression levels of cytokines such as interleukin-6, tumor necrosis factor-α, and interferon-γ were significantly suppressed after LPS injection in the transgenic mouse liver. Induction of the C-C motif chemokine ligand 2, 4, and 5 was also suppressed. Phosphorylation of the signal transducer and activator of transcription 3, which is activated by cytokines, was also reduced, and expression levels of interferon-stimulated genes, 2'-5' oligoadenylate synthase, interferon-inducible double-stranded RNA-activated protein kinase, and myxovirus resistance 1 were similarly suppressed. Since LPS binds to toll-like receptor 4 and stimulates the downstream pathway leading to induction of these genes, we examined the extracellular signal-regulated kinase and IκB-α. The phosphorylation levels of these molecules were reduced in transgenic mouse liver, indicating that the pathway upstream of the molecules was disrupted by NS5A. Further analyses revealed that the interaction between interleukin-1 receptor-associated kinase-1 and tumor necrosis factor receptor associated factor-6 was dispersed in transgenic mice, suggesting that NS5A may interfere with this interaction via myeloid differentiation primary response gene 88, which was shown to interact with NS5A. Since the gut microbiota, a source of LPS, is known to be associated with pathological conditions in liver diseases, our results suggest the involvement of NS5A in the pathogenesis of HCV infected-liver via the suppression of innate immunity.

  1. Lower levels of interleukin-1β gene expression are associated with impaired Langerhans' cell migration in aged human skin.

    Science.gov (United States)

    Pilkington, Suzanne M; Ogden, Stephanie; Eaton, Laura H; Dearman, Rebecca J; Kimber, Ian; Griffiths, Christopher E M

    2018-01-01

    Langerhans' cells (LC) play pivotal roles in skin immune responses, linking innate and adaptive immunity. In aged skin there are fewer LC and migration is impaired compared with young skin. These changes may contribute to declining skin immunity in the elderly, including increased skin infections and skin cancer. Interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α) are mandatory signals for LC migration and previous studies suggest that IL-1β signalling may be dysregulated in aged skin. Therefore, we sought to explore the mechanisms underlying these phenomena. In skin biopsies of photoprotected young ( 70 years) human skin ex vivo, we assessed the impact of trauma, and mandatory LC mobilizing signals on LC migration and gene expression. Biopsy-related trauma induced LC migration from young epidermis, whereas in aged skin, migration was greatly reduced. Interleukin-1β treatment restored LC migration in aged epidermis whereas TNF-α was without effect. In uncultured, aged skin IL-1β gene expression was lower compared with young skin; following culture, IL-1βmRNA remained lower in aged skin under control and TNF-α conditions but was elevated after culture with IL-1β. Interleukin-1 receptor type 2 (IL1R2) gene expression was significantly increased in aged, but not young skin, after cytokine treatment. Keratinocyte-derived factors secreted from young and aged primary cells did not restore or inhibit LC migration from aged and young epidermis, respectively. These data suggest that in aged skin, IL-1β signalling is diminished due to altered expression of IL1B and decoy receptor gene IL1R2. © 2017 The Authors. Immunology Published by John Wiley & Sons Ltd., Immunology.

  2. CD86 and beta2-adrenergic receptor signaling pathways, respectively, increase Oct-2 and OCA-B Expression and binding to the 3'-IgH enhancer in B cells.

    Science.gov (United States)

    Podojil, Joseph R; Kin, Nicholas W; Sanders, Virginia M

    2004-05-28

    Stimulation of CD86 (formerly known as B7-2) and/or the beta2-adrenergic receptor on a CD40 ligand/interleukin-4-activated B cell increased the rate of mature IgG1 transcription. To identify the mechanism responsible for this effect, we determined whether CD86 and/or beta2-adrenergic receptor stimulation regulated transcription factor expression and binding to the 3'-IgH enhancer in vitro and in vivo. We showed that CD86 stimulation increased the nuclear localization of NF-kappaB1 (p50) and phosphorylated RelA (p65) and increased Oct-2 expression and binding to the 3'-IgH enhancer, in a protein kinase C-dependent manner. These effects were lost when CD86-deficient or NF-kappaB1-deficient B cells were used. CD86 stimulation also increased the level of IkappaB-alpha phosphorylation but in a protein kinase C-independent manner. Beta2-adrenergic receptor stimulation increased CREB phosphorylation, OCA-B expression, and OCA-B binding to the 3'-IgH enhancer in a protein kinase A-dependent manner, an effect lost when beta2-adrenergic receptor-deficient B cells were used. Also, the beta2-adrenergic receptor-induced increase in the level of mature IgG1 transcript was lost when OCA-B-deficient B cells were used. These data are the first to show that CD86 stimulation up-regulates the expression of the transcription factor Oct-2 in a protein kinase C- and NF-kappaB1-dependent manner, and that beta2-adrenergic receptor stimulation up-regulates the expression of the coactivator OCA-B in a protein kinase A-dependent manner to cooperate with Oct-2 binding to the 3'-IgH enhancer.

  3. Misexpression of AtTX12 encoding a Toll/interleukin-1 receptor domain induces growth defects and expression of defense-related genes partially independently of EDS1 in Arabidopsis.

    Science.gov (United States)

    Song, Sang-Kee

    2016-12-01

    In this study, a tissue-specific GAL4/UAS activation tagging system was used for the characterization of genes which could induce lethality when ubiquitously expressed. A dominant mutant exhibiting stunted growth was isolated and named defective root development 1-D (drd1-D). The T-DNA tag was located within the promoter region of AtTX12, which is predicted to encode a truncated nucleotide-binding leucinerich repeat (NLR) protein, containing a Toll/interleukin-1 receptor (TIR) domain. The transcript levels of AtTX12 and defense-related genes were elevated in drd1-D, and the misexpression of AtTX12 recapitulated the drd1-D phenotypes. In the presence of ENHANCED DISEASE SUSCEPTIBILITY 1 (EDS1), a key transducer of signals triggered by TIR-type NLRs, a low-level of AtTX12 misexpression induced strong defective phenotypes including seedling lethality whereas, in the absence of EDS1, a high-level of AtTX12 misexpression induced weak growth defects like dwarfism, suggesting that AtTX12 might function mainly in an EDS1-dependent and partially in an EDS1-independent manner. [BMB Reports 2016; 49(12): 693-698].

  4. Adenosine A2A receptor-dependent proliferation of pulmonary endothelial cells is mediated through calcium mobilization, PI3-kinase and ERK1/2 pathways

    International Nuclear Information System (INIS)

    Ahmad, Aftab; Schaack, Jerome B.; White, Carl W.; Ahmad, Shama

    2013-01-01

    Highlights: •A 2A receptor-induced pulmonary endothelial growth is mediated by PI3K and ERK1/2. •Cytosolic calcium mobilization is also critical for pulmonary endothelial growth. •Effectors of A 2A receptor, like tyrosine kinases and cAMP increase PI3K/Akt signaling. •Activation of A 2A receptor can contribute to vascular remodeling. -- Abstract: Hypoxia and HIF-2α-dependent A 2A receptor expression and activation increase proliferation of human lung microvascular endothelial cells (HLMVECs). This study was undertaken to investigate the signaling mechanisms that mediate the proliferative effects of A 2A receptor. A 2A receptor-mediated proliferation of HLMVECs was inhibited by intracellular calcium chelation, and by specific inhibitors of ERK1/2 and PI3-kinase (PI3K). The adenosine A 2A receptor agonist CGS21680 caused intracellular calcium mobilization in controls and, to a greater extent, in A 2A receptor-overexpressing HLMVECs. Adenoviral-mediated A 2A receptor overexpression as well as receptor activation by CGS21680 caused increased PI3K activity and Akt phosphorylation. Cells overexpressing A 2A receptor also manifested enhanced ERK1/2 phosphorylation upon CGS21680 treatment. A 2A receptor activation also caused enhanced cAMP production. Likewise, treatment with 8Br-cAMP increased PI3K activity. Hence A 2A receptor-mediated cAMP production and PI3K and Akt phosphorylation are potential mediators of the A 2A -mediated proliferative response of HLMVECs. Cytosolic calcium mobilization and ERK1/2 phosphorylation are other critical effectors of HLMVEC proliferation and growth. These studies underscore the importance of adenosine A 2A receptor in activation of survival and proliferative pathways in pulmonary endothelial cells that are mediated through PI3K/Akt and ERK1/2 pathways

  5. G protein-coupled receptors (GPCRs) That Signal via Protein Kinase A (PKA) Cross-talk at Insulin Receptor Substrate 1 (IRS1) to Activate the phosphatidylinositol 3-kinase (PI3K)/AKT Pathway.

    Science.gov (United States)

    Law, Nathan C; White, Morris F; Hunzicker-Dunn, Mary E

    2016-12-30

    G protein-coupled receptors (GPCRs) activate PI3K/v-AKT thymoma viral oncoprotein (AKT) to regulate many cellular functions that promote cell survival, proliferation, and growth. However, the mechanism by which GPCRs activate PI3K/AKT remains poorly understood. We used ovarian preantral granulosa cells (GCs) to elucidate the mechanism by which the GPCR agonist FSH via PKA activates the PI3K/AKT cascade. Insulin-like growth factor 1 (IGF1) is secreted in an autocrine/paracrine manner by GCs and activates the IGF1 receptor (IGF1R) but, in the absence of FSH, fails to stimulate YXXM phosphorylation of IRS1 (insulin receptor substrate 1) required for PI3K/AKT activation. We show that PKA directly phosphorylates the protein phosphatase 1 (PP1) regulatory subunit myosin phosphatase targeting subunit 1 (MYPT1) to activate PP1 associated with the IGF1R-IRS1 complex. Activated PP1 is sufficient to dephosphorylate at least four IRS1 Ser residues, Ser 318 , Ser 346 , Ser 612 , and Ser 789 , and promotes IRS1 YXXM phosphorylation by the IGF1R to activate the PI3K/AKT cascade. Additional experiments indicate that this mechanism also occurs in breast cancer, thyroid, and preovulatory granulosa cells, suggesting that the PKA-dependent dephosphorylation of IRS1 Ser/Thr residues is a conserved mechanism by which GPCRs signal to activate the PI3K/AKT pathway downstream of the IGF1R. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Interleukin-36 cytokines may overcome microbial immune evasion strategies that inhibit interleukin-1 family signaling.

    Science.gov (United States)

    Jensen, Liselotte E

    2017-08-15

    Pathogens deploy immune evasion strategies to successfully establish infections within their hosts. Naturally, the host responds by acquiring mechanisms to counter these strategies. There is increasing evidence that the three interleukin-36 (IL-36) cytokines, IL-36α, IL-36β and IL-36γ, play important roles in host immunity. With a focus on the skin as a target for microbial and viral invasion, the current knowledge of IL-36 functions is reviewed. Furthermore, the hypothesis that the IL-36s have evolved to counteract virulence factors is presented using viruses as an example. The IL-36s are related to IL-1α, IL-1β, IL-18, and IL-33. Numerous viruses affecting the skin have developed immune evasion strategies that neutralize IL-1α, IL-1β, or IL-18 signaling or combinations of these pathways. Through small differences in activation mechanisms and receptor utilization, it is possible that IL-36 signaling may proceed unhindered in the presence of these viral inhibitors. Thus, one physiological function of the IL-36s may be to counteract microbial immune evasion. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  7. NK cell cytotoxicity mediated by 2B4 and NTB-A is dependent on SAP acting downstream of receptor phosphorylation

    Directory of Open Access Journals (Sweden)

    Stephan eMeinke

    2013-01-01

    Full Text Available 2B4 (CD244 and NK-T-B-antigen (NTB-A, CD352 are activating receptors on human NK cells and belong to the family of SLAM-related receptors. Engagement of these receptors leads to phosphorylation of their cytoplasmic tails and recruitment of the adapter proteins SAP and EAT-2. X-linked lymphoproliferative syndrome (XLP is a severe immunodeficiency that results from mutations in the SAP gene. 2B4 and NTB-A-mediated cytotoxicity are abrogated in XLP NK cells. To elucidate the molecular basis for this defect we analyzed early signaling events in SAP knockdown cells. Similar to XLP NK cells, knockdown of SAP in primary human NK cells leads to a reduction of 2B4 and NTB-A-mediated cytotoxicity. We found that early signaling events such as raft recruitment and receptor phosphorylation are not affected by the absence of SAP, indicating the defect in the absence of SAP is downstream of these events. In addition, knockdown of EAT-2 does not impair 2B4 or NTB-A-mediated cytotoxicity. Surprisingly, EAT-2 recruitment to both receptors is abrogated in the absence of SAP, revealing a novel cooperativity between these adapters.

  8. Receptor-type Protein Tyrosine Phosphatase β Regulates Met Phosphorylation and Function in Head and Neck Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Yiru Xu

    2012-11-01

    Full Text Available Head and neck squamous cell carcinoma (HNSCC is the sixth most common cancer and has a high rate of mortality. Emerging evidence indicates that hepatocyte growth factor receptor (or Met pathway plays a pivotal role in HNSCC metastasis and resistance to chemotherapy. Met function is dependent on tyrosine phosphorylation that is under direct control by receptor-type protein tyrosine phosphatase β (RPTP-β. We report here that RPTP-β expression is significantly downregulated in HNSCC cells derived from metastatic tumors compared to subject-matched cells from primary tumors. Knockdown of endogenous RPTP-β in HNSCC cells from primary tumor potentiated Met tyrosine phosphorylation, downstream mitogen-activated protein (MAP kinase pathway activation, cell migration, and invasion. Conversely, restoration of RPTP-β expression in cells from matched metastatic tumor decreased Met tyrosine phosphorylation and downstream functions. Furthermore, we observed that six of eight HNSCC tumors had reduced levels of RPTP-β protein in comparison with normal oral tissues. Collectively, the results demonstrate the importance of RPTP-β in tumor biology of HNSCC through direct dephosphorylation of Met and regulation of downstream signal transduction pathways. Reduced RPTP-β levels, with or without Met overexpression, could promote Met activation in HNSCC tumors.

  9. Interaction of the phosphorylated DNA-binding domain in nuclear receptor CAR with its ligand-binding domain regulates CAR activation.

    Science.gov (United States)

    Shizu, Ryota; Min, Jungki; Sobhany, Mack; Pedersen, Lars C; Mutoh, Shingo; Negishi, Masahiko

    2018-01-05

    The nuclear protein constitutive active/androstane receptor (CAR or NR1I3) regulates several liver functions such as drug and energy metabolism and cell growth or death, which are often involved in the development of diseases such as diabetes and hepatocellular carcinoma. CAR undergoes a conversion from inactive homodimers to active heterodimers with retinoid X receptor α (RXRα), and phosphorylation of the DNA-binding domain (DBD) at Thr-38 in CAR regulates this conversion. Here, we uncovered the molecular mechanism by which this phosphorylation regulates the intramolecular interaction between CAR's DBD and ligand-binding domain (LBD), enabling the homodimer-heterodimer conversion. Phosphomimetic substitution of Thr-38 with Asp increased co-immunoprecipitation of the CAR DBD with CAR LBD in Huh-7 cells. Isothermal titration calorimetry assays also revealed that recombinant CAR DBD-T38D, but not nonphosphorylated CAR DBD, bound the CAR LBD peptide. This DBD-LBD interaction masked CAR's dimer interface, preventing CAR homodimer formation. Of note, EGF signaling weakened the interaction of CAR DBD T38D with CAR LBD, converting CAR to the homodimer form. The DBD-T38D-LBD interaction also prevented CAR from forming a heterodimer with RXRα. However, this interaction opened up a CAR surface, allowing interaction with protein phosphatase 2A. Thr-38 dephosphorylation then dissociated the DBD-LBD interaction, allowing CAR heterodimer formation with RXRα. We conclude that the intramolecular interaction of phosphorylated DBD with the LBD enables CAR to adapt a transient monomer configuration that can be converted to either the inactive homodimer or the active heterodimer.

  10. Hyperactivity of Hypothalamic-Pituitary-Adrenal Axis Due to Dysfunction of the Hypothalamic Glucocorticoid Receptor in Sigma-1 Receptor Knockout Mice

    Directory of Open Access Journals (Sweden)

    Tingting Di

    2017-09-01

    Full Text Available Sigma-1 receptor knockout (σ1R-KO mice exhibit a depressive-like phenotype. Because σ1R is highly expressed in the neuronal cells of hypothalamic paraventricular nuclei (PVN, this study investigated the influence of σ1R deficiency on the regulation of the hypothalamic-pituitary-adrenocortical (HPA axis. Here, we show that the levels of basal serum corticosterone (CORT, adrenocorticotropic hormone (ACTH and corticotrophin releasing factor (CRF as well as the level of CRF mRNA in PVN did not significantly differ between adult male σ1R-KO mice and wild-type (WT mice. Acute mild restraint stress (AMRS induced a higher and more sustainable increase in activity of HPA axis and CRF expression in σ1R-KO mice. Percentage of dexamethasone (Dex-induced reduction in level of CORT was markedly attenuated in σ1R−/− mice. The levels of glucocorticoid receptor (GR and protein kinase C (PKC phosphorylation were reduced in the PVN of σ1R-KO mice and σ1R antagonist NE100-treated WT mice. The exposure to AMRS in σ1R-KO mice induced a stronger phosphorylation of cAMP-response element binding protein (CREB in PVN than that in WT mice. Intracerebroventricular (i.c.v. injection of PKC activator PMA for 3 days in σ1R-KO mice not only recovered the GR phosphorylation and the percentage of Dex-reduced CORT but also corrected the AMRS-induced hyperactivity of HPA axis and enhancement of CRF mRNA and CREB phosphorylation. Furthermore, the injection (i.c.v. of PMA in σ1R-KO mice corrected the prolongation of immobility time in forced swim test (FST and tail suspension test (TST. These results indicate that σ1R deficiency causes down-regulation of GR by reducing PKC phosphorylation, which attenuates GR-mediated feedback inhibition of HPA axis and facilitates the stress response of HPA axis leading to the production of depressive-like behaviors.

  11. Spinal Tolerance and Dependence: Some Observations on the Role of Spinal N-Methyl-D-Aspartate Receptors and Phosphorylation in the Loss of Opioid Analgesic Responses

    Directory of Open Access Journals (Sweden)

    Tony L Yaksh

    2000-01-01

    Full Text Available The continuous delivery of opiates can lead to a reduction in analgesic effects. In humans, as in other animals, some component of this change in sensitivity seems likely to have a strong pharmacodynamic component. Such loss of effect, deemed to be tolerance in the present article, can be readily demonstrated in animals with repeated bolus and continuous intrathecal infusion of mu and delta opioids and alpha-2 adrenergic agonists. Research has shown that this loss of effect can be diminished by concurrent treatment with N-methyl-D-aspartate (NMDA receptor antagonists and by the suppression of the activity of spinal protein kinase C (PKC. This suggests in part the probable role of PKC-mediated phosphorylation in the right shift in the dose-effect curves observed with continuous opiate or adrenergic exposure. Importantly, this right shift is seen to occur in parallel with an increase in the phosphorylating activity in the dorsal horn and in the expression of several PKC isozymes. The target of this phosphorylation is not certain. Phosphorylation of the NMDA receptor enhances its functionality, while phosphorylation of the opioid receptor or associated channels seems to diminish their activity or to enhance internalization. While the focus is on several specific components, the accumulating data emphasize the biological complexity of these changes in spinal drug reactivity.

  12. Cross-regulation of cytokine signalling: pro-inflammatory cytokines restrict IL-6 signalling through receptor internalisation and degradation.

    Science.gov (United States)

    Radtke, Simone; Wüller, Stefan; Yang, Xiang-ping; Lippok, Barbara E; Mütze, Barbara; Mais, Christine; de Leur, Hildegard Schmitz-Van; Bode, Johannes G; Gaestel, Matthias; Heinrich, Peter C; Behrmann, Iris; Schaper, Fred; Hermanns, Heike M

    2010-03-15

    The inflammatory response involves a complex interplay of different cytokines which act in an auto- or paracrine manner to induce the so-called acute phase response. Cytokines are known to crosstalk on multiple levels, for instance by regulating the mRNA stability of targeted cytokines through activation of the p38-MAPK pathway. In our study we discovered a new mechanism that answers the long-standing question how pro-inflammatory cytokines and environmental stress restrict immediate signalling of interleukin (IL)-6-type cytokines. We show that p38, activated by IL-1beta, TNFalpha or environmental stress, impairs IL-6-induced JAK/STAT signalling through phosphorylation of the common cytokine receptor subunit gp130 and its subsequent internalisation and degradation. We identify MK2 as the kinase that phosphorylates serine 782 in the cytoplasmic part of gp130. Consequently, inhibition of p38 or MK2, deletion of MK2 or mutation of crucial amino acids within the MK2 target site or the di-leucine internalisation motif blocks receptor depletion and restores IL-6-dependent STAT activation as well as gene induction. Hence, a novel negative crosstalk mechanism for cytokine signalling is described, where cytokine receptor turnover is regulated in trans by pro-inflammatory cytokines and stress stimuli to coordinate the inflammatory response.

  13. Inter-domain tagging implicates caveolin-1 in insulin receptor trafficking and Erk signaling bias in pancreatic beta-cells

    Directory of Open Access Journals (Sweden)

    Tobias Boothe

    2016-05-01

    Full Text Available Objective: The role and mechanisms of insulin receptor internalization remain incompletely understood. Previous trafficking studies of insulin receptors involved fluorescent protein tagging at their termini, manipulations that may be expected to result in dysfunctional receptors. Our objective was to determine the trafficking route and molecular mechanisms of functional tagged insulin receptors and endogenous insulin receptors in pancreatic beta-cells. Methods: We generated functional insulin receptors tagged with pH-resistant fluorescent proteins between domains. Confocal, TIRF and STED imaging revealed a trafficking pattern of inter-domain tagged insulin receptors and endogenous insulin receptors detected with antibodies. Results: Surprisingly, interdomain-tagged and endogenous insulin receptors in beta-cells bypassed classical Rab5a- or Rab7-mediated endocytic routes. Instead, we found that removal of insulin receptors from the plasma membrane involved tyrosine-phosphorylated caveolin-1, prior to trafficking within flotillin-1-positive structures to lysosomes. Multiple methods of inhibiting caveolin-1 significantly reduced Erk activation in vitro or in vivo, while leaving Akt signaling mostly intact. Conclusions: We conclude that phosphorylated caveolin-1 plays a role in insulin receptor internalization towards lysosomes through flotillin-1-positive structures and that caveolin-1 helps bias physiological beta-cell insulin signaling towards Erk activation. Author Video: Author Video Watch what authors say about their articles Keywords: Insulin receptor internalization, Insulin resistance, Pancreatic islet beta-cells, Autocrine insulin signaling

  14. Interleukin-6 and interleukin-1 production in acute leukemia with monocytoid differentiation

    NARCIS (Netherlands)

    van der Schoot, C. E.; Jansen, P.; Poorter, M.; Wester, M. R.; von dem Borne, A. E.; Aarden, L. A.; van Oers, R. H.

    1989-01-01

    Several authors have reported the in vitro production of colony-stimulating factors (CSF) and interleukin-1 (IL-1) by the neoplastic cells from patients with acute myeloid leukemia (AML). Using a sensitive bioassay for IL-6, the capacity of the leukemic cells of 30 patients with AML to produce IL-6

  15. Interleukins 1alpha and 1beta secreted by some melanoma cell lines strongly reduce expression of MITF-M and melanocyte differentiation antigens.

    Science.gov (United States)

    Kholmanskikh, Olga; van Baren, Nicolas; Brasseur, Francis; Ottaviani, Sabrina; Vanacker, Julie; Arts, Nathalie; van der Bruggen, Pierre; Coulie, Pierre; De Plaen, Etienne

    2010-10-01

    We report that melanoma cell lines expressing the interleukin-1 receptor exhibit 4- to 10-fold lower levels of mRNA of microphthalmia-associated transcription factor (MITF-M) when treated with interleukin-1beta. This effect is NF-kappaB and JNK-dependent. MITF-M regulates the expression of melanocyte differentiation genes such as MLANA, tyrosinase and gp100, which encode antigens recognized on melanoma cells by autologous cytolytic T lymphocytes. Accordingly, treating some melanoma cells with IL-1beta reduced by 40-100% their ability to activate such antimelanoma cytolytic T lymphocytes. Finally, we observed large amounts of biologically active IL-1alpha or IL-1beta secreted by two melanoma cell lines that did not express MITF-M, suggesting an autocrine MITF-M downregulation. We estimate that approximately 13% of melanoma cell lines are MITF-M-negative and secrete IL-1 cytokines. These results indicate that the repression of melanocyte-differentiation genes by IL-1 produced by stromal cells or by tumor cells themselves may represent an additional mechanism of melanoma immune escape.

  16. Endothelin-1 stimulates catalase activity through the PKCδ mediated phosphorylation of Serine 167

    Science.gov (United States)

    Rafikov, Ruslan; Kumar, Sanjiv; Aggarwal, Saurabh; Hou, Yali; Kangath, Archana; Pardo, Daniel; Fineman, Jeffrey R.; Black, Stephen M.

    2013-01-01

    Our previous studies have shown that endothelin-1 (ET-1) stimulates catalase activity in endothelial cells and lambs with acute increases in pulmonary blood flow (PBF), without altering gene expression. The purpose of this study was to investigate the molecular mechanism by which this occurs. Exposing pulmonary arterial endothelial cells (PAEC) to ET-1 increased catalase activity and decreased cellular hydrogen peroxide (H2O2) levels. These changes correlated with an increase in serine phosphorylated catalase. Using the inhibitory peptide δV1.1, this phosphorylation was shown to be PKCδ dependent. Mass spectrometry identified serine167 as the phosphorylation site. Site-directed mutagenesis was used to generate a phospho-mimic (S167D) catalase. Activity assays using recombinant protein purified from E.coli or transiently transfected COS-7 cells, demonstrated that S167D-catalase had an increased ability to degrade H2O2 compared to the wildtype enzyme. Using a phospho-specific antibody, we were able to verify that pS167 catalase levels are modulated in lambs with acute increases in PBF in the presence and absence of the ET receptor antagonist, tezosentan. S167 is being located on the dimeric interface suggesting it could be involved in regulating the formation of catalase tetramers. To evaluate this possibility we utilized analytical gel-filtration to examine the multimeric structure of recombinant wildtype- and S167D-catalase. We found that recombinant wildtype catalase was present as a mixture of monomers and dimers while S167D catalase was primarily tetrameric. Further, the incubation of wildtype catalase with PKCδ was sufficient to convert wildtype catalase into a tetrameric structure. In conclusion, this is the first report indicating that the phosphorylation of catalase regulates its multimeric structure and activity. PMID:24211614

  17. Viral vector mediated continuous expression of interleukin-10 in DRG alleviates pain in type 1 diabetic animals.

    Science.gov (United States)

    Thakur, Vikram; Gonzalez, Mayra; Pennington, Kristen; Chattopadhyay, Munmun

    2016-04-01

    Painful diabetic neuropathy is a common and difficult to treat complication of diabetes. A growing body of evidence implicates the role of inflammatory mediators in the damage to the peripheral axons and in the pathogenesis of neuropathic pain. Increased expression of pro-inflammatory cytokines such as interleukin (IL)-1β and tumor necrosis factor (TNF)-α in the peripheral nervous system suggests the possibility of change in pain perception in diabetes. In this study we investigated that continuous delivery of IL10 in the nerve fibers achieved by HSV vector mediated transduction of dorsal root ganglion (DRG) in animals with Type 1 diabetes, blocks the nociceptive and stress responses in the DRG neurons by reducing IL1β expression along with inhibition of phosphorylation of p38 MAPK (mitogen-activated protein kinase) and protein kinase C (PKC). The continuous expression of IL10 also alters Toll like receptor (TLR)-4 expression in the DRG with increased expression of heat shock protein (HSP)-70 in conjunction with the reduction of pain. Taken together, this study suggests that macrophage activation in the peripheral nervous system may be involved in the pathogenesis of pain in Type 1 diabetes and therapeutic benefits of HSV mediated local expression of IL10 in the DRG with the reduction of a number of proinflammatory cytokines, subsequently inhibits the development of painful neuropathy along with a decrease in stress associated markers in the DRG. This basic and preclinical study provides an important evidence for a novel treatment strategy that could lead to a clinical trial for what is currently a treatment resistant complication of diabetes. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Signal-transducing mechanisms of ketamine-caused inhibition of interleukin-1β gene expression in lipopolysaccharide-stimulated murine macrophage-like Raw 264.7 cells

    International Nuclear Information System (INIS)

    Chen, T.-L.; Chang, C.-C.; Lin, Y.-L.; Ueng, Y.-F.; Chen, R.-M.

    2009-01-01

    Ketamine may affect the host immunity. Interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) are pivotal cytokines produced by macrophages. This study aimed to evaluate the effects of ketamine on the regulation of inflammatory cytokine gene expression, especially IL-1β, in lipopolysaccharide (LPS)-activated murine macrophage-like Raw 264.7 cells and its possible signal-transducing mechanisms. Administration of Raw 264.7 cells with a therapeutic concentration of ketamine (100 μM), LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. Exposure to 100 μM ketamine decreased the binding affinity of LPS and LPS-binding protein but did not affect LPS-induced RNA and protein synthesis of TLR4. Treatment with LPS significantly increased IL-1β, IL-6, and TNF-α gene expressions in Raw 264.7 cells. Ketamine at a clinically relevant concentration did not affect the synthesis of these inflammatory cytokines, but significantly decreased LPS-caused increases in these cytokines. Immunoblot analyses, an electrophoretic mobility shift assay, and a reporter luciferase activity assay revealed that ketamine significantly decreased LPS-induced translocation and DNA binding activity of nuclear factor-kappa B (NFκB). Administration of LPS sequentially increased the phosphorylations of Ras, Raf, MEK1/2, ERK1/2, and IKK. However, a therapeutic concentration of ketamine alleviated such augmentations. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA reduced cellular TLR4 amounts and ameliorated LPS-induced RAS activation and IL-1β synthesis. Co-treatment with ketamine and TLR4 siRNA synergistically ameliorated LPS-caused enhancement of IL-1β production. Results of this study show that a therapeutic concentration of ketamine can inhibit gene expression of IL-1β possibly through suppressing TLR4-mediated signal-transducing phosphorylations of Ras, Raf, MEK1/2, ERK1/2, and IKK and subsequent translocation and

  19. STAT6 Mediates Interleukin-4 Growth Inhibition in Human Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Jennifer L. Gooch

    2002-01-01

    Full Text Available In addition to acting as a hematopoietic growth factor, interleukin-4 (IL-4 inhibits growth of some transformed cells in vitro and in vivo. In this study, we show that insulin receptor substrate (IRS-1, IRS-2, and signal transducer and activator of transcription 6 (STAT6 are phosphorylated following IL-4 treatment in MCF-7 breast cancer cells. STAT6 DNA binding is enhanced by IL-4 treatment. STAT6 activation occurs even after IRS-1 depletion, suggesting the two pathways are independent. To examine the role of STAT6 in IL-4-mediated growth inhibition and apoptosis, a fulllength STAT6 cDNA was transfected into MCF-7 cells. Transient overexpression of STAT6 resulted in both cytoplasmic and nuclear expression of the protein, increased DNA binding in response to IL-4, and increased transactivation of an IL-4 responsive promoter. In STAT6-transfected cells, basal proliferation was reduced whereas apoptosis was increased. Finally, stable expression of STAT6 resulted in reduced foci formation compared to vector-transfected cells alone. These results suggest STAT6 is required for IL-4mediated growth inhibition and induction of apoptosis in human breast cancer cells.

  20. Crystallization and preliminary X-ray diffraction of human interleukin-7 bound to unglycosylated and glycosylated forms of its α-receptor

    Energy Technology Data Exchange (ETDEWEB)

    Wickham, Joseph Jr; Walsh, Scott T. R., E-mail: walsh.220@osu.edu [Department of Molecular and Cellular Biochemistry, Comprehensive Cancer Center, Ohio State University, 467 Hamilton Hall, 1645 Neil Avenue, Columbus, OH 43210 (United States)

    2007-10-01

    Bacterial and insect cell expression systems have been developed to produce unglycosylated and glycosylated forms of human interleukin-7 (IL-7) and the extracellular domain of its α receptor, IL-7Rα. We report the crystallization and X-ray diffraction of IL-7 complexes to both unglycosylated and glycosylated forms of the IL-7Rα to 2.7 and 3.0 Å, respectively. The interleukin-7 (IL-7) signaling pathway plays an essential role in the development, proliferation and homeostasis of T and B cells in cell-mediated immunity. Understimulation and overstimulation of the IL-7 signaling pathway leads to severe combined immunodeficiency, autoimmune reactions, heart disease and cancers. Stimulation of the IL-7 pathway begins with IL-7 binding to its α-receptor, IL-7Rα. Protein crystals of unglycosylated and glycosylated complexes of human IL-7–IL-7Rα extracellular domain (ECD) obtained using a surface entropy-reduction approach diffract to 2.7 and 3.0 Å, respectively. Anomalous dispersion methods will be used to solve the unglycosylated IL-7–IL-7Rα ECD complex structure and this unglycosylated structure will then serve as a model in molecular-replacement attempts to solve the structure of the glycosylated IL-7–α-receptor complex.

  1. Crystallization and preliminary X-ray diffraction of human interleukin-7 bound to unglycosylated and glycosylated forms of its α-receptor

    International Nuclear Information System (INIS)

    Wickham, Joseph Jr; Walsh, Scott T. R.

    2007-01-01

    Bacterial and insect cell expression systems have been developed to produce unglycosylated and glycosylated forms of human interleukin-7 (IL-7) and the extracellular domain of its α receptor, IL-7Rα. We report the crystallization and X-ray diffraction of IL-7 complexes to both unglycosylated and glycosylated forms of the IL-7Rα to 2.7 and 3.0 Å, respectively. The interleukin-7 (IL-7) signaling pathway plays an essential role in the development, proliferation and homeostasis of T and B cells in cell-mediated immunity. Understimulation and overstimulation of the IL-7 signaling pathway leads to severe combined immunodeficiency, autoimmune reactions, heart disease and cancers. Stimulation of the IL-7 pathway begins with IL-7 binding to its α-receptor, IL-7Rα. Protein crystals of unglycosylated and glycosylated complexes of human IL-7–IL-7Rα extracellular domain (ECD) obtained using a surface entropy-reduction approach diffract to 2.7 and 3.0 Å, respectively. Anomalous dispersion methods will be used to solve the unglycosylated IL-7–IL-7Rα ECD complex structure and this unglycosylated structure will then serve as a model in molecular-replacement attempts to solve the structure of the glycosylated IL-7–α-receptor complex

  2. Experimental transmission of AA amyloidosis by injecting the AA amyloid protein into interleukin-1 receptor antagonist knockout (IL-1raKO) mice.

    Science.gov (United States)

    Watanabe, K; Uchida, K; Chambers, J K; Tei, M; Shoji, A; Ushio, N; Nakayama, H

    2015-05-01

    The incidence of AA amyloidosis is high in humans with rheumatoid arthritis and several animal species, including cats and cattle with prolonged inflammation. AA amyloidosis can be experimentally induced in mice using severe inflammatory stimuli and a coinjection of AA amyloid; however, difficulties have been associated with transmitting AA amyloidosis to a different animal species, and this has been attributed to the "species barrier." The interleukin-1 receptor antagonist knockout (IL-1raKO) mouse, a rodent model of human rheumatoid arthritis, has been used in the transmission of AA amyloid. When IL-1raKO and BALB/c mice were intraperitoneally injected with mouse AA amyloid together with a subcutaneous pretreatment of 2% AgNO3, all mice from both strains that were injected with crude or purified murine AA amyloid developed AA amyloidosis. However, the amyloid index, which was determined by the intensity of AA amyloid deposition, was significantly higher in IL-1raKO mice than in BALB/c mice. When IL-1raKO and BALB/c mice were injected with crude or purified bovine AA amyloid together with the pretreatment, 83% (5/6 cases) and 38% (3/8 cases) of IL-1raKO mice and 17% (1/6 cases) and 0% (0/6 cases) of BALB/c mice, respectively, developed AA amyloidosis. Similarly, when IL-1raKO and BALB/c mice were injected with crude or purified feline AA amyloid, 33% (2/6 cases) and 88% (7/8 cases) of IL-1raKO mice and 0% (0/6 cases) and 29% (2/6 cases) of BALB/c mice, respectively, developed AA amyloidosis. These results indicated that IL-1raKO mice are a useful animal model for investigating AA amyloidogenesis. © The Author(s) 2014.

  3. Lemur tyrosine kinase-2 signalling regulates kinesin-1 light chain-2 phosphorylation and binding of Smad2 cargo.

    LENUS (Irish Health Repository)

    Manser, C

    2012-05-31

    A recent genome-wide association study identified the gene encoding lemur tyrosine kinase-2 (LMTK2) as a susceptibility gene for prostate cancer. The identified genetic alteration is within intron 9, but the mechanisms by which LMTK2 may impact upon prostate cancer are not clear because the functions of LMTK2 are poorly understood. Here, we show that LMTK2 regulates a known pathway that controls phosphorylation of kinesin-1 light chain-2 (KLC2) by glycogen synthase kinase-3β (GSK3β). KLC2 phosphorylation by GSK3β induces the release of cargo from KLC2. LMTK2 signals via protein phosphatase-1C (PP1C) to increase inhibitory phosphorylation of GSK3β on serine-9 that reduces KLC2 phosphorylation and promotes binding of the known KLC2 cargo Smad2. Smad2 signals to the nucleus in response to transforming growth factor-β (TGFβ) receptor stimulation and transport of Smad2 by kinesin-1 is required for this signalling. We show that small interfering RNA loss of LMTK2 not only reduces binding of Smad2 to KLC2, but also inhibits TGFβ-induced Smad2 signalling. Thus, LMTK2 may regulate the activity of kinesin-1 motor function and Smad2 signalling.

  4. Haloperidol Regulates the State of Phosphorylation of Ribosomal Protein S6 via Activation of PKA and Phosphorylation of DARPP-32

    Science.gov (United States)

    Valjent, Emmanuel; Bertran-Gonzalez, Jesus; Bowling, Heather; Lopez, Sébastien; Santini, Emanuela; Matamales, Miriam; Bonito-Oliva, Alessandra; Hervé, Denis; Hoeffer, Charles; Klann, Eric; Girault, Jean-Antoine; Fisone, Gilberto

    2011-01-01

    Administration of typical antipsychotic drugs, such as haloperidol, promotes cAMP-dependent signaling in the medium spiny neurons (MSNs) of the striatum. In this study, we have examined the effect of haloperidol on the state of phosphorylation of the ribosomal protein S6 (rpS6), a component of the small 40S ribosomal subunit. We found that haloperidol increases the phosphorylation of rpS6 at the dual site Ser235/236, which is involved in the regulation of mRNA translation. This effect was exerted in the MSNs of the indirect pathway, which express specifically dopamine D2 receptors (D2Rs) and adenosine A2 receptors (A2ARs). The effect of haloperidol was decreased by blockade of A2ARs or by genetic attenuation of the Gαolf protein, which couples A2ARs to activation of adenylyl cyclase. Moreover, stimulation of cAMP-dependent protein kinase A (PKA) increased Ser235/236 phosphorylation in cultured striatal neurons. The ability of haloperidol to promote rpS6 phosphorylation was abolished in knock-in mice deficient for PKA activation of the protein phosphatase-1 inhibitor, dopamine- and cAMP-regulated phosphoprotein of 32 kDa. In contrast, pharmacological or genetic inactivation of p70 rpS6 kinase 1, or extracellular signal-regulated kinases did not affect haloperidol-induced rpS6 phosphorylation. These results identify PKA as a major rpS6 kinase in neuronal cells and suggest that regulation of protein synthesis through rpS6 may be a potential target of antipsychotic drugs. PMID:21814187

  5. Neurexin-1β Binding to Neuroligin-1 Triggers the Preferential Recruitment of PSD-95 versus Gephyrin through Tyrosine Phosphorylation of Neuroligin-1

    Directory of Open Access Journals (Sweden)

    Grégory Giannone

    2013-06-01

    Full Text Available Adhesion between neurexin-1β (Nrx1β and neuroligin-1 (Nlg1 induces early recruitment of the postsynaptic density protein 95 (PSD-95 scaffold; however, the associated signaling mechanisms are unknown. To dissociate the effects of ligand binding and receptor multimerization, we compared conditions in which Nlg1 in neurons was bound to Nrx1β or nonactivating HA antibodies. Time-lapse imaging, fluorescence recovery after photobleaching, and single-particle tracking demonstrated that in addition to aggregating Nlg1, Nrx1β binding stimulates the interaction between Nlg1 and PSD-95. Phosphotyrosine immunoblots and pull-down of gephyrin by Nlg1 peptides in vitro showed that Nlg1 can be phosphorylated at a unique tyrosine (Y782, preventing gephyrin binding. Expression of Nlg1 point mutants in neurons indicated that Y782 phosphorylation controls the preferential binding of Nlg1 to PSD-95 versus gephyrin, and accordingly the formation of inhibitory and excitatory synapses. We propose that ligand-induced changes in the Nlg1 phosphotyrosine level control the balance between excitatory and inhibitory scaffold assembly during synapse formation and stabilization.

  6. Combined Blockade of Interleukin-1α and -1β Signaling Protects Mice from Cognitive Dysfunction after Traumatic Brain Injury.

    Science.gov (United States)

    Newell, Elizabeth A; Todd, Brittany P; Mahoney, Jolonda; Pieper, Andrew A; Ferguson, Polly J; Bassuk, Alexander G

    2018-01-01

    Diffuse activation of interleukin-1 inflammatory cytokine signaling after traumatic brain injury (TBI) elicits progressive neurodegeneration and neuropsychiatric dysfunction, and thus represents a potential opportunity for therapeutic intervention. Although interleukin (IL)-1α and IL-1β both activate the common type 1 IL-1 receptor (IL-1RI), they manifest distinct injury-specific roles in some models of neurodegeneration. Despite its potential relevance to treating patients with TBI, however, the individual contributions of IL-1α and IL-1β to TBI-pathology have not been previously investigated. To address this need, we applied genetic and pharmacologic approaches in mice to dissect the individual contributions of IL-1α, IL-β, and IL-1RI signaling to the pathophysiology of fluid percussion-mediated TBI, a model of mixed focal and diffuse TBI. IL-1RI ablation conferred a greater protective effect on brain cytokine expression and cognitive function after TBI than did individual IL-1α or IL-1β ablation. This protective effect was recapitulated by treatment with the drug anakinra, a recombinant naturally occurring IL-1RI antagonist. Our data thus suggest that broad targeting of IL-1RI signaling is more likely to reduce neuroinflammation and preserve cognitive function after TBI than are approaches that individually target IL-1α or IL-1β signaling.

  7. Regulated internalization of NMDA receptors drives PKD1-mediated suppression of the activity of residual cell-surface NMDA receptors.

    Science.gov (United States)

    Fang, Xiao-Qian; Qiao, Haifa; Groveman, Bradley R; Feng, Shuang; Pflueger, Melissa; Xin, Wen-Kuan; Ali, Mohammad K; Lin, Shuang-Xiu; Xu, Jindong; Duclot, Florian; Kabbaj, Mohamed; Wang, Wei; Ding, Xin-Sheng; Santiago-Sim, Teresa; Jiang, Xing-Hong; Salter, Michael W; Yu, Xian-Min

    2015-11-19

    Constitutive and regulated internalization of cell surface proteins has been extensively investigated. The regulated internalization has been characterized as a principal mechanism for removing cell-surface receptors from the plasma membrane, and signaling to downstream targets of receptors. However, so far it is still not known whether the functional properties of remaining (non-internalized) receptor/channels may be regulated by internalization of the same class of receptor/channels. The N-methyl-D-aspartate receptor (NMDAR) is a principal subtype of glutamate-gated ion channel and plays key roles in neuronal plasticity and memory functions. NMDARs are well-known to undergo two types of regulated internalization - homologous and heterologous, which can be induced by high NMDA/glycine and DHPG, respectively. In the present work, we investigated effects of regulated NMDAR internalization on the activity of residual cell-surface NMDARs and neuronal functions. In electrophysiological experiments we discovered that the regulated internalization of NMDARs not only reduced the number of cell surface NMDARs but also caused an inhibition of the activity of remaining (non-internalized) surface NMDARs. In biochemical experiments we identified that this functional inhibition of remaining surface NMDARs was mediated by increased serine phosphorylation of surface NMDARs, resulting from the activation of protein kinase D1 (PKD1). Knockdown of PKD1 did not affect NMDAR internalization but prevented the phosphorylation and inhibition of remaining surface NMDARs and NMDAR-mediated synaptic functions. These data demonstrate a novel concept that regulated internalization of cell surface NMDARs not only reduces the number of NMDARs on the cell surface but also causes an inhibition of the activity of remaining surface NMDARs through intracellular signaling pathway(s). Furthermore, modulating the activity of remaining surface receptors may be an effective approach for treating receptor

  8. Phosphorylation of the cytoplasmic tail of the 300-kDa mannose 6-phosphate receptor is required for the interaction with a cytosolic protein

    DEFF Research Database (Denmark)

    Rosorius, O; Issinger, O G; Braulke, T

    1993-01-01

    The cytoplasmic tail of the human 300-kDa mannose 6-phosphate receptor (MPR 300-CT) is an excellent substrate for casein kinase II in vitro. The phosphorylated MPR 300-CT was cross-linked by means of bis(sulfosuccinimidyl)suberate mainly to a cytosolic protein of 35 kDa (referred to as TIP 35...... with TIP 35 is phosphorylation-specific. Furthermore, TIP 35 was only cross-linked to the MPR 300-CT phosphorylated by casein kinase II whereas the MPR 300-CT phosphorylated by protein kinase A failed to cross-link to TIP 35. These results indicate that the cytoplasmic tail of the MPR 300 interacts...

  9. Phosphorylated hepatocyte growth factor receptor/c-Met is associated with tumor growth and prognosis in patients with bladder cancer: correlation with matrix metalloproteinase-2 and -7 and E-cadherin.

    Science.gov (United States)

    Miyata, Yasuyoshi; Sagara, Yuji; Kanda, Shigeru; Hayashi, Tomayoshi; Kanetake, Hiroshi

    2009-04-01

    Hepatocyte growth factor receptor/c-Met is associated with malignant aggressiveness and survival in various cancers including bladder cancer. Although phosphorylation of hepatocyte growth factor receptor/c-Met is essential for its function, the pathologic significance of phosphorylated hepatocyte growth factor receptor/c-Met in bladder cancer remains elusive. We investigated the clinical significance of its expression, and its correlation with cancer cell progression-related molecules. The expression levels of 2 tyrosine residues of hepatocyte growth factor receptor/c-Met (pY1234/1235 and pY1349) were examined immunohistochemically in 133 specimens with nonmetastatic bladder cancer. We also investigated their correlation with matrix metalloproteinase-1, -2, -7, and -14; urokinase-type plasminogen activator; E-cadherin; CD44 standard, variant 3, and variant 6; and vascular endothelial growth factor. Expression of phosphorylated hepatocyte growth factor receptor/c-Met was detected in cancer cells, but was rare in normal urothelial cells. Although hepatocyte growth factor receptor/c-Met, pY1234/1235 hepatocyte growth factor receptor/c-Met, and pY1349 hepatocyte growth factor receptor/c-Met were associated with pT stage, multivariate analysis identified pY1349 hepatocyte growth factor receptor/c-met expression only as a significant factor for high pT stage. Expression of pY1349 hepatocyte growth factor receptor/c-Met was a marker of metastasis and (P = .001) and cause-specific survival (P = .003). Expressions of matrix metalloproteinase-2, matrix metalloproteinase-7, and E-cadherin correlated with pY1349 hepatocyte growth factor receptor/c-Met expression. Our results demonstrated that pY1349 hepatocyte growth factor receptor/c-Met plays an important role in tumor development, and its expression is a significant predictor of metastasis and survival of patients with bladder cancer. The results suggest that these activities are mediated, at least in part, by matrix

  10. Internalization of the human CRF receptor 1 is independent of classical phosphorylation sites and of beta-arrestin 1 recruitment

    DEFF Research Database (Denmark)

    Rasmussen, Trine N; Novak, Ivana; Nielsen, Søren M

    2004-01-01

    The corticotropin releasing factor receptor 1 (CRFR1) belongs to the superfamily of G-protein coupled receptors. Though CRF is involved in the aetiology of several stress-related disorders, including depression and anxiety, details of CRFR1 regulation such as internalization remain uncharacterized...

  11. Phosphorylation of AIB1 at Mitosis Is Regulated by CDK1/CYCLIN B

    Science.gov (United States)

    Ferrero, Macarena; Ferragud, Juan; Orlando, Leonardo; Valero, Luz; Sánchez del Pino, Manuel; Farràs, Rosa; Font de Mora, Jaime

    2011-01-01

    Background Although the AIB1 oncogene has an important role during the early phase of the cell cycle as a coactivator of E2F1, little is known about its function during mitosis. Methodology/Principal Findings Mitotic cells isolated by nocodazole treatment as well as by shake-off revealed a post-translational modification occurring in AIB1 specifically during mitosis. This modification was sensitive to the treatment with phosphatase, suggesting its modification by phosphorylation. Using specific inhibitors and in vitro kinase assays we demonstrate that AIB1 is phosphorylated on Ser728 and Ser867 by Cdk1/cyclin B at the onset of mitosis and remains phosphorylated until exit from M phase. Differences in the sensitivity to phosphatase inhibitors suggest that PP1 mediates dephosphorylation of AIB1 at the end of mitosis. The phosphorylation of AIB1 during mitosis was not associated with ubiquitylation or degradation, as confirmed by western blotting and flow cytometry analysis. In addition, luciferase reporter assays showed that this phosphorylation did not alter the transcriptional properties of AIB1. Importantly, fluorescence microscopy and sub-cellular fractionation showed that AIB1 phosphorylation correlated with the exclusion from the condensed chromatin, thus preventing access to the promoters of AIB1-dependent genes. Phospho-specific antibodies developed against Ser728 further demonstrated the presence of phosphorylated AIB1 only in mitotic cells where it was localized preferentially in the periphery of the cell. Conclusions Collectively, our results describe a new mechanism for the regulation of AIB1 during mitosis, whereby phosphorylation of AIB1 by Cdk1 correlates with the subcellular redistribution of AIB1 from a chromatin-associated state in interphase to a more peripheral localization during mitosis. At the exit of mitosis, AIB1 is dephosphorylated, presumably by PP1. This exclusion from chromatin during mitosis may represent a mechanism for governing the

  12. c-Abl Mediated Tyrosine Phosphorylation of Aha1 Activates Its Co-chaperone Function in Cancer Cells

    Directory of Open Access Journals (Sweden)

    Diana M. Dunn

    2015-08-01

    Full Text Available The ability of Heat Shock Protein 90 (Hsp90 to hydrolyze ATP is essential for its chaperone function. The co-chaperone Aha1 stimulates Hsp90 ATPase activity, tailoring the chaperone function to specific “client” proteins. The intracellular signaling mechanisms directly regulating Aha1 association with Hsp90 remain unknown. Here, we show that c-Abl kinase phosphorylates Y223 in human Aha1 (hAha1, promoting its interaction with Hsp90. This, consequently, results in an increased Hsp90 ATPase activity, enhances Hsp90 interaction with kinase clients, and compromises the chaperoning of non-kinase clients such as glucocorticoid receptor and CFTR. Suggesting a regulatory paradigm, we also find that Y223 phosphorylation leads to ubiquitination and degradation of hAha1 in the proteasome. Finally, pharmacologic inhibition of c-Abl prevents hAha1 interaction with Hsp90, thereby hypersensitizing cancer cells to Hsp90 inhibitors both in vitro and ex vivo.

  13. Interleukin-10 increases reverse cholesterol transport in macrophages through its bidirectional interaction with liver X receptor α

    International Nuclear Information System (INIS)

    Halvorsen, Bente; Holm, Sverre; Yndestad, Arne; Scholz, Hanne; Sagen, Ellen Lund; Nebb, Hilde; Holven, Kirsten B.; Dahl, Tuva B.; Aukrust, Pål

    2014-01-01

    Highlights: • IL-10 promotes reverse cholesterol efflux from lipid loaded macrophages. • IL-10 increases the expression of ABCA-1 and ABCG-1. • IL-10 exhibits cross-talk with the nuclear receptor LXRα. - Abstract: Interleukin (IL)-10 is a prototypical anti-inflammatory cytokine that has been shown to attenuate atherosclerosis development. In addition to its anti-inflammatory properties, the anti-atherogenic effect of IL-10 has recently also been suggested to reflect a complex effect of IL-10 on lipid metabolism in macrophages. In the present study we examined the effects of IL-10 on cholesterol efflux mechanism in lipid-loaded THP-1 macrophages. Our main findings were: (i) IL-10 significantly enhanced cholesterol efflux induced by fetal-calf serum, high-density lipoprotein (HDL) 2 and apolipoprotein A-1. (ii) The IL-10-mediated effects on cholesterol efflux were accompanied by an increased IL-10-mediated expression of the ATP-binding cassette transporters ABCA1 and ABCG1, that was further enhanced when the cells were co-activated with the liver X receptor (LXR)α agonist (22R)-hydroxycholesterol. (iii) The effect of LXRα activation on the IL-10-mediated effects on the ATP-binding cassette transporters seems to include enhancing effects on the IL-10 receptor 1 (IL10R1) expression and interaction with STAT-3 signaling. (iv) These enhancing effects on ABCA1 and ABCG1 was not seen when the cells were stimulated with the IL-10 family members IL-22 and IL-24. This study suggests that the anti-atherogenic properties of IL-10 may include enhancing effects on cholesterol efflux mechanism that involves cross-talk with LXRα activation

  14. Interleukin-10 increases reverse cholesterol transport in macrophages through its bidirectional interaction with liver X receptor α

    Energy Technology Data Exchange (ETDEWEB)

    Halvorsen, Bente, E-mail: Bente.Halvorsen@rr-research.no [Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway); K.G. Jebsen Inflammation Research Center, University of Oslo, Oslo (Norway); Holm, Sverre [Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo (Norway); Yndestad, Arne [Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway); K.G. Jebsen Inflammation Research Center, University of Oslo, Oslo (Norway); Scholz, Hanne [Section for Transplantation, Institute for Surgical Research, Oslo University Hospital Rikshospitalet, Oslo (Norway); Sagen, Ellen Lund [Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo (Norway); Nebb, Hilde [Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway); Holven, Kirsten B. [Department of Nutrition, Institute for Basic Medical Sciences, University of Oslo, Oslo (Norway); Dahl, Tuva B. [Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway); Aukrust, Pål [Research Institute of Internal Medicine, Oslo University Hospital Rikshospitalet, Oslo (Norway); Section of Clinical Immunology and Infectious Diseases, Oslo University Hospital Rikshospitalet, Oslo (Norway); Institute of Clinical Medicine, University of Oslo, Oslo (Norway); K.G. Jebsen Inflammation Research Center, University of Oslo, Oslo (Norway)

    2014-08-08

    Highlights: • IL-10 promotes reverse cholesterol efflux from lipid loaded macrophages. • IL-10 increases the expression of ABCA-1 and ABCG-1. • IL-10 exhibits cross-talk with the nuclear receptor LXRα. - Abstract: Interleukin (IL)-10 is a prototypical anti-inflammatory cytokine that has been shown to attenuate atherosclerosis development. In addition to its anti-inflammatory properties, the anti-atherogenic effect of IL-10 has recently also been suggested to reflect a complex effect of IL-10 on lipid metabolism in macrophages. In the present study we examined the effects of IL-10 on cholesterol efflux mechanism in lipid-loaded THP-1 macrophages. Our main findings were: (i) IL-10 significantly enhanced cholesterol efflux induced by fetal-calf serum, high-density lipoprotein (HDL){sub 2} and apolipoprotein A-1. (ii) The IL-10-mediated effects on cholesterol efflux were accompanied by an increased IL-10-mediated expression of the ATP-binding cassette transporters ABCA1 and ABCG1, that was further enhanced when the cells were co-activated with the liver X receptor (LXR)α agonist (22R)-hydroxycholesterol. (iii) The effect of LXRα activation on the IL-10-mediated effects on the ATP-binding cassette transporters seems to include enhancing effects on the IL-10 receptor 1 (IL10R1) expression and interaction with STAT-3 signaling. (iv) These enhancing effects on ABCA1 and ABCG1 was not seen when the cells were stimulated with the IL-10 family members IL-22 and IL-24. This study suggests that the anti-atherogenic properties of IL-10 may include enhancing effects on cholesterol efflux mechanism that involves cross-talk with LXRα activation.

  15. Expression of FLNa in human melanoma cells regulates the function of integrin α1β1 and phosphorylation and localisation of PKB/AKT/ERK1/2 kinases.

    Science.gov (United States)

    Krebs, Kristi; Ruusmann, Anu; Simonlatser, Grethel; Velling, Teet

    2015-12-01

    FLNa is a ubiquitous cytoskeletal protein that links transmembrane receptors, including integrins, to F-actin and functions as a signalling intermediate. We investigated FLNa's role in the function of integrin-type collagen receptors, EGF-EGFR signalling and regulation of PKB/Akt and ERK1/2. Using FLNa-deficient M2 human melanoma cells, and same cells expressing EGFP-FLNa (M2F) or its Ig-like repeats 1-8+24, 8-15+24 and 16-24, we found that in M2F and M2 8-15+24 cells, EGF induced the increased phosphorylation of PKB/Akt and ERK1/2. In M2F cells EGF induced the localisation of these kinases to cell nucleus and lamellipodia, respectively, and the ERK1/2 phosphorylation-dependent co-immunoprecipitation of FLNa with ERK1/2. Only M2F and M2 8-15+24 cells adhered to and spread on type I collagen whereas on fibronectin all cells behaved similarly. α1β1 and α2β1 were the integrin-type collagen receptors expressed on these cells with primarily α1β1 localising to focal contacts and affecting cell adhesion and migration in a manner dependent on FLNa or its Ig-like repeats 8-15. Our results suggest a role for FLNa repeats 8-15 in the α1-subunit-dependent regulation of integrin α1β1 function, EGF-EGFR signalling to PKB/Akt and ERK1/2, identify ERK1/2 in EGF-induced FLNa-associated protein complexes, and show that the function of different integrins is subjected to differential regulation by FLNa. Copyright © 2015. Published by Elsevier GmbH.

  16. mTORC1 directly phosphorylates and regulates human MAF1.

    Science.gov (United States)

    Michels, Annemieke A; Robitaille, Aaron M; Buczynski-Ruchonnet, Diane; Hodroj, Wassim; Reina, Jaime H; Hall, Michael N; Hernandez, Nouria

    2010-08-01

    mTORC1 is a central regulator of growth in response to nutrient availability, but few direct targets have been identified. RNA polymerase (pol) III produces a number of essential RNA molecules involved in protein synthesis, RNA maturation, and other processes. Its activity is highly regulated, and deregulation can lead to cell transformation. The human phosphoprotein MAF1 becomes dephosphorylated and represses pol III transcription after various stresses, but neither the significance of the phosphorylations nor the kinase involved is known. We find that human MAF1 is absolutely required for pol III repression in response to serum starvation or TORC1 inhibition by rapamycin or Torin1. The protein is phosphorylated mainly on residues S60, S68, and S75, and this inhibits its pol III repression function. The responsible kinase is mTORC1, which phosphorylates MAF1 directly. Our results describe molecular mechanisms by which mTORC1 controls human MAF1, a key repressor of RNA polymerase III transcription, and add a new branch to the signal transduction cascade immediately downstream of TORC1.

  17. Ex vivo modulation of the Foxo1 phosphorylation state does not lead to dysfunction of T regulatory cells.

    Directory of Open Access Journals (Sweden)

    Kristen Kelley Penberthy

    Full Text Available Peripheral regulatory CD4+ T cells (Treg cells prevent maladaptive inflammatory responses to innocuous foreign antigens. Treg cell dysfunction has been linked to many inflammatory diseases, including allergic airway inflammation. Glucocorticoids that are used to treat allergic airway inflammation and asthma are thought to work in part by promoting Treg cell differentiation; patients who are refractory to these drugs have defective induction of anti-inflammatory Treg cells. Previous observations suggest that Treg cells deficient in the transcription factor FoxO1 are pro-inflammatory, and that FoxO1 activity is regulated by its phosphorylation status and nuclear localization. Here, we asked whether altering the phosphorylation state of FoxO1 through modulation of a regulatory phosphatase might affect Treg cell function. In a mouse model of house dust mite-induced allergic airway inflammation, we observed robust recruitment of Treg cells to the lungs and lymph nodes of diseased mice, without an apparent increase in the Treg cytokine interleukin-10 in the airways. Intriguingly, expression of PP2A, a serine/threonine phosphatase linked to the regulation of FoxO1 phosphorylation, was decreased in the mediastinal lymph nodes of HDM-treated mice, mirroring the decreased PP2A expression seen in peripheral blood monocytes of glucocorticoid-resistant asthmatic patients. When we asked whether modulation of PP2A activity alters Treg cell function via treatment with the PP2A inhibitor okadaic acid, we observed increased phosphorylation of FoxO1 and decreased nuclear localization. However, dysregulation of FoxO1 did not impair Treg cell differentiation ex vivo or cause Treg cells to adopt a pro-inflammatory phenotype. Moreover, inhibition of PP2A activity did not affect the suppressive function of Treg cells ex vivo. Collectively, these data suggest that modulation of the phosphorylation state of FoxO1 via PP2A inhibition does not modify Treg cell function ex

  18. Production of bioactive soluble interleukin-15 in complex with interleukin-15 receptor alpha from a conditionally-replicating oncolytic HSV-1.

    Directory of Open Access Journals (Sweden)

    David C Gaston

    Full Text Available Oncolytic type-1 herpes simplex viruses (oHSVs lacking the γ134.5 neurovirulence gene are being evaluated for treatment of a variety of malignancies. oHSVs replicate within and directly kill permissive cancer cells. To augment their anti-tumor activity, oHSVs have been engineered to express immunostimulatory molecules, including cytokines, to elicit tumor-specific immune responses. Interleukin-15 (IL-15 holds potential as an immunotherapeutic cytokine because it has been demonstrated to promote both natural killer (NK cell-mediated and CD8(+ T cell-mediated cytotoxicity against cancer cells. The purpose of these studies was to engineer an oHSV producing bioactive IL-15. Two oHSVs were constructed encoding murine (mIL-15 alone (J100 or with the mIL-15 receptor α (mIL-15Rα, J100D to determine whether co-expression of these proteins is required for production of bioactive mIL-15 from oHSV. The following were demonstrated: i both oHSVs retain replication competence and cytotoxicity in permissive tumor cell lines. ii Enhanced production of mIL-15 was detected in cell lysates of neuro-2a cells following J100D infection as compared to J100 infection, suggesting that mIL-15Rα improved mIL-15 production. iii Soluble mIL-15 in complex with mIL-15Rα was detected in supernates from J100D-infected, but not J100-infected, neuro-2a, GL261, and CT-2A cells. These cell lines vary in permissiveness to oHSV replication and cytotoxicity, demonstrating soluble mIL-15/IL-15Rα complex production from J100D was independent of direct oHSV effects. iv The soluble mIL-15/IL-15Rα complex produced by J100D was bioactive, stimulating NK cells to proliferate and reduce the viability of syngeneic GL261 and CT-2A cells. v J100 and J100D were aneurovirulent inasmuch as no neuropathologic effects were documented following direct inoculation into brains of CBA/J mice at up to 1x10(7 plaque forming units. The production of mIL-15/mIL-15Rα from multiple tumor lines, as well

  19. Mutation of androgen receptor N-terminal phosphorylation site Tyr-267 leads to inhibition of nuclear translocation and DNA binding.

    Directory of Open Access Journals (Sweden)

    Mehmet Karaca

    Full Text Available Reactivation of androgen receptor (AR may drive recurrent prostate cancer in castrate patients. Ack1 tyrosine kinase is overexpressed in prostate cancer and promotes castrate resistant xenograft tumor growth and enhances androgen target gene expression and AR recruitment to enhancers. Ack1 phosphorylates AR at Tyr-267 and possibly Tyr-363, both in the N-terminal transactivation domain. In this study, the role of these phosphorylation sites was investigated by characterizing the phosphorylation site mutants in the context of full length and truncated AR lacking the ligand-binding domain. Y267F and Y363F mutants showed decreased transactivation of reporters. Expression of wild type full length and truncated AR in LNCaP cells increased cell proliferation in androgen-depleted conditions and increased colony formation. However, the Y267F mutant of full length and truncated AR was defective in stimulating cell proliferation. The Y363F mutant was less severely affected than the Y267F mutant. The full length AR Y267F mutant was defective in nuclear translocation induced by androgen or Ack1 kinase. The truncated AR was constitutively localized to the nucleus. Chromatin immunoprecipitation analysis showed that it was recruited to the target enhancers without androgen. The truncated Y267F AR mutant did not exhibit constitutive nuclear localization and androgen enhancer binding activity. These results support the concept that phosphorylation of Tyr-267, and to a lesser extent Tyr-363, is required for AR nuclear translocation and recruitment and DNA binding and provide a rationale for development of novel approaches to inhibit AR activity.

  20. [Function of the interleukin-1 gene system in immunomodulation, apoptosis and proliferation in the male gonad].

    Science.gov (United States)

    Rozwadowska, Natalia; Fiszer, Dorota; Kurpisz, Maciej

    2005-03-07

    Spermatogenesis is a phenomenon where two main processes proliferation and apoptosis, meet. Slight changes in their activities could lead to different pathologies, such as fertility disorder (excessive apoptosis) or testicular cancer (overproliferation). The IL-1 gene family includes genes which play important roles in both these processes and consists of IL-1?, IL-1ss, IL-18, the IL-1 receptor antagonist (IL-1RA), two IL-1 receptors (IL-1RI, IL-1RII), the IL-18 receptor (IL-18R?), and the receptor-associated proteins - IL-1RAcP and IL-18Rss. Caspase-1 (ICE - interleukin-1 converting enzyme), directly connected with apoptosis and responsible for the cleavage of IL-1b and IL-18, is also a member of the IL-1 family. The system of the numerous IL-1 receptors and their signal transduction involving protein cascades provokes a range of gene expressions necessary for the initiation and maintenance of inflammatory reaction. In the testis, IL-1 is constitutively expressed, where it creates a unique microenvironment for diploid gametogenic cell conversion into specialized haploid spermatozoa. It may also be an element of the physiological protection from autoimmune attack by host testicular antigens and a part of immune privilege. This review is to summarize the knowledge of the local control of spermatogenesis and immunomodulation in the male gonad. As infertility is one of the main problems of industrialized countries, study of the pathophysiology of the male genital tract appears essential in future clinical practice.

  1. Tyrosine phosphorylation of Eps15 is required for ligand-regulated, but not constitutive, endocytosis

    DEFF Research Database (Denmark)

    Confalonieri, S; Salcini, A E; Puri, C

    2000-01-01

    for endocytosis of the epidermal growth factor receptor (EGFR), the prototypical ligand-inducible receptor, but not of the transferrin receptor (TfR), the prototypical constitutively internalized receptor. Eps15, an endocytic protein that is tyrosine phosphorylated by EGFR, is a candidate for such a function....... Here, we show that tyrosine phosphorylation of Eps15 is necessary for internalization of the EGFR, but not of the TfR. We mapped Tyr 850 as the major in vivo tyrosine phosphorylation site of Eps15. A phosphorylation-negative mutant of Eps15 acted as a dominant negative on the internalization...... of the EGFR, but not of the TfR. A phosphopeptide, corresponding to the phosphorylated sequence of Eps15, inhibited EGFR endocytosis, suggesting that phosphotyrosine in Eps15 serves as a docking site for a phosphotyrosine binding protein. Thus, tyrosine phosphorylation of Eps15 represents the first molecular...

  2. PTP1B regulates Eph receptor function and trafficking

    OpenAIRE

    Nievergall, Eva; Janes, Peter W.; Stegmayer, Carolin; Vail, Mary E.; Haj, Fawaz G.; Teng, Shyh Wei; Neel, Benjamin G.; Bastiaens, Philippe I.; Lackmann, Martin

    2010-01-01

    Eph receptors orchestrate cell positioning during normal and oncogenic development. Their function is spatially and temporally controlled by protein tyrosine phosphatases (PTPs), but the underlying mechanisms are unclear and the identity of most regulatory PTPs are unknown. We demonstrate here that PTP1B governs signaling and biological activity of EphA3. Changes in PTP1B expression significantly affect duration and amplitude of EphA3 phosphorylation and biological function, whereas confocal ...

  3. Phosphorylation of Ser1928 mediates the enhanced activity of the L-type Ca2+ channel Cav1.2 by the β2-adrenergic receptor in neurons.

    Science.gov (United States)

    Qian, Hai; Patriarchi, Tommaso; Price, Jennifer L; Matt, Lucas; Lee, Boram; Nieves-Cintrón, Madeline; Buonarati, Olivia R; Chowdhury, Dhrubajyoti; Nanou, Evanthia; Nystoriak, Matthew A; Catterall, William A; Poomvanicha, Montatip; Hofmann, Franz; Navedo, Manuel F; Hell, Johannes W

    2017-01-24

    The L-type Ca 2+ channel Ca v 1.2 controls multiple functions throughout the body including heart rate and neuronal excitability. It is a key mediator of fight-or-flight stress responses triggered by a signaling pathway involving β-adrenergic receptors (βARs), cyclic adenosine monophosphate (cAMP), and protein kinase A (PKA). PKA readily phosphorylates Ser 1928 in Ca v 1.2 in vitro and in vivo, including in rodents and humans. However, S1928A knock-in (KI) mice have normal PKA-mediated L-type channel regulation in the heart, indicating that Ser 1928 is not required for regulation of cardiac Ca v 1.2 by PKA in this tissue. We report that augmentation of L-type currents by PKA in neurons was absent in S1928A KI mice. Furthermore, S1928A KI mice failed to induce long-term potentiation in response to prolonged theta-tetanus (PTT-LTP), a form of synaptic plasticity that requires Ca v 1.2 and enhancement of its activity by the β 2 -adrenergic receptor (β 2 AR)-cAMP-PKA cascade. Thus, there is an unexpected dichotomy in the control of Ca v 1.2 by PKA in cardiomyocytes and hippocampal neurons. Copyright © 2017, American Association for the Advancement of Science.

  4. The Interplay of the Interleukin 1 System in Pregnancy and Labor

    Science.gov (United States)

    Liong, Stella; Permezel, Michael; Rice, Gregory E.; Quinzio, Megan K. W. Di; Georgiou, Harry M.

    2014-01-01

    This work assessed the temporal coexpression of interleukin 1 (IL-1) and its inhibitor, IL-1 receptor antagonist (IL-1ra), in the cervicovaginal fluid (CVF) beyond 24 weeks gestation including women in spontaneous term labor. Two cohorts of women were recruited at 24 to 35 weeks’ gestation (n = 65) and in late pregnancy (>36 weeks’ gestation; n = 88). The CVF was serially collected either every 4 weeks between 24 and 35 weeks’ gestation (n = 123 samples) or weekly during late pregnancy (n = 240 samples). The IL-1 and IL-1ra were quantitated by enzyme-linked immunosorbent assay, and the effect of vaginal microflora and unprotected sexual intercourse were also investigated. The IL-1β and IL-1ra remain unaltered between 24 and 35 weeks’ gestation. At late pregnancy, IL-1α and β concentrations peak at 4 to 14 days prior to labor onset, while IL-1ra decreases with approaching spontaneous term labor (P labor with 86% sensitivity and 92% specificity. This study indicates a shifting inflammatory balance in the gestational tissues prior to labor onset. PMID:23749763

  5. Subcellular distribution of cyclin-dependent kinase-like 5 (CDKL5) is regulated through phosphorylation by dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A)

    International Nuclear Information System (INIS)

    Oi, Ami; Katayama, Syouichi; Hatano, Naoya; Sugiyama, Yasunori; Kameshita, Isamu; Sueyoshi, Noriyuki

    2017-01-01

    Cyclin-dependent kinase-like 5 (CDKL5) is a Ser/Thr protein kinase primarily expressed in the central nervous system and is known to cause X-linked neurodevelopmental disorders such as Rett syndrome. However, the mechanisms regulating CDKL5 have not yet been fully clarified. Therefore, in this study, we investigated the protein kinase that directly phosphorylates CDKL5, identifying it as dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A), an enzyme binding to and phosphorylating CDKL5. We showed that subcellular distribution of CDKL5 was regulated by its phosphorylation by DYRK1A. In mouse neuroblastoma Neuro2a cells, CDKL5 was localized in both the cytosol and nucleus, whereas DYRK1A showed a typical nuclear localization. When CDKL5 and DYRK1A were co-expressed, the cytosolic localization of CDKL5 was significantly increased. Results of site-directed mutagenesis revealed that the phosphorylation site was Ser-308, in the vicinity of the nuclear localization signal. A mutation mimicking the phosphorylated serine residue by aspartate substitution (S308D) changed CDKL5 localization to the cytosol, whereas the corresponding alanine-substituted analog, CDKL5(S308A), was primarily localized to the nucleus. Taken together, these results strongly suggested that DYRK1A bound to CDKL5 and phosphorylated it on Ser-308, thus interfering with its nuclear localization. - Highlights: • We investigated the mechanism regulating subcellular localization of CDKL5. • DYRK1A was identified as an enzyme that bound to and phosphorylated CDKL5. • The phosphorylation site of CDKL5 was Ser-308, in the vicinity of the NLS. • When DYRK1A was co-expressed, the cytosolic CDKL5 was significantly increased. • In conclusion, DYRK1A regulates CDKL5 localization via phosphorylation on Ser-308.

  6. Cardiac adverse effects of naloxone-precipitated morphine withdrawal on right ventricle: Role of corticotropin-releasing factor (CRF) 1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Navarro-Zaragoza, J.; Martínez-Laorden, E.; Mora, L.; Hidalgo, J.; Milanés, M.V.; Laorden, M.L., E-mail: laorden@um.es

    2014-02-15

    Opioid addiction is associated with cardiovascular disease. However, mechanisms linking opioid addiction and cardiovascular disease remain unclear. This study investigated the role of corticotropin-releasing factor (CRF) 1 receptor in mediating somatic signs and the behavioural states produced during withdrawal from morphine dependence. Furthermore, it studied the efficacy of CRF1 receptor antagonist, CP-154,526 to prevent the cardiac sympathetic activity induced by morphine withdrawal. In addition, tyrosine hydroxylase (TH) phosphorylation pathways were evaluated. Like stress, morphine withdrawal induced an increase in the hypothalamic–pituitary–adrenal (HPA) axis activity and an enhancement of noradrenaline (NA) turnover. Pre-treatment with CRF1 receptor antagonist significantly reduced morphine withdrawal-induced increases in plasma adrenocorticotropic hormone (ACTH) levels, NA turnover and TH phosphorylation at Ser31 in the right ventricle. In addition, CP-154,526 reduced the phosphorylation of extracellular signal-regulated kinase (ERK) after naloxone-precipitated morphine withdrawal. In addition, CP-154,526 attenuated the increases in body weight loss during morphine treatment and suppressed some of morphine withdrawal signs. Altogether, these results support the idea that cardiac sympathetic pathways are activated in response to naloxone-precipitated morphine withdrawal suggesting that treatment with a CRF1 receptor antagonist before morphine withdrawal would prevent the development of stress-induced behavioural and autonomic dysfunction in opioid addicts. - Highlights: • Morphine withdrawal caused an increase in myocardial sympathetic activity. • ERK regulates TH phosphorylation after naloxone-induced morphine withdrawal. • CRF1R is involved in cardiac adaptive changes during morphine dependence.

  7. Cardiac adverse effects of naloxone-precipitated morphine withdrawal on right ventricle: Role of corticotropin-releasing factor (CRF) 1 receptor

    International Nuclear Information System (INIS)

    Navarro-Zaragoza, J.; Martínez-Laorden, E.; Mora, L.; Hidalgo, J.; Milanés, M.V.; Laorden, M.L.

    2014-01-01

    Opioid addiction is associated with cardiovascular disease. However, mechanisms linking opioid addiction and cardiovascular disease remain unclear. This study investigated the role of corticotropin-releasing factor (CRF) 1 receptor in mediating somatic signs and the behavioural states produced during withdrawal from morphine dependence. Furthermore, it studied the efficacy of CRF1 receptor antagonist, CP-154,526 to prevent the cardiac sympathetic activity induced by morphine withdrawal. In addition, tyrosine hydroxylase (TH) phosphorylation pathways were evaluated. Like stress, morphine withdrawal induced an increase in the hypothalamic–pituitary–adrenal (HPA) axis activity and an enhancement of noradrenaline (NA) turnover. Pre-treatment with CRF1 receptor antagonist significantly reduced morphine withdrawal-induced increases in plasma adrenocorticotropic hormone (ACTH) levels, NA turnover and TH phosphorylation at Ser31 in the right ventricle. In addition, CP-154,526 reduced the phosphorylation of extracellular signal-regulated kinase (ERK) after naloxone-precipitated morphine withdrawal. In addition, CP-154,526 attenuated the increases in body weight loss during morphine treatment and suppressed some of morphine withdrawal signs. Altogether, these results support the idea that cardiac sympathetic pathways are activated in response to naloxone-precipitated morphine withdrawal suggesting that treatment with a CRF1 receptor antagonist before morphine withdrawal would prevent the development of stress-induced behavioural and autonomic dysfunction in opioid addicts. - Highlights: • Morphine withdrawal caused an increase in myocardial sympathetic activity. • ERK regulates TH phosphorylation after naloxone-induced morphine withdrawal. • CRF1R is involved in cardiac adaptive changes during morphine dependence

  8. APPL1 potentiates insulin sensitivity by facilitating the binding of IRS1/2 to the insulin receptor.

    Science.gov (United States)

    Ryu, Jiyoon; Galan, Amanda K; Xin, Xiaoban; Dong, Feng; Abdul-Ghani, Muhammad A; Zhou, Lijun; Wang, Changhua; Li, Cuiling; Holmes, Bekke M; Sloane, Lauren B; Austad, Steven N; Guo, Shaodong; Musi, Nicolas; DeFronzo, Ralph A; Deng, Chuxia; White, Morris F; Liu, Feng; Dong, Lily Q

    2014-05-22

    Binding of insulin receptor substrate proteins 1 and 2 (IRS1/2) to the insulin receptor (IR) is essential for the regulation of insulin sensitivity and energy homeostasis. However, the mechanism of IRS1/2 recruitment to the IR remains elusive. Here, we identify adaptor protein APPL1 as a critical molecule that promotes IRS1/2-IR interaction. APPL1 forms a complex with IRS1/2 under basal conditions, and this complex is then recruited to the IR in response to insulin or adiponectin stimulation. The interaction between APPL1 and IR depends on insulin- or adiponectin-stimulated APPL1 phosphorylation, which is greatly reduced in insulin target tissues in obese mice. appl1 deletion in mice consistently leads to systemic insulin resistance and a significant reduction in insulin-stimulated IRS1/2, but not IR, tyrosine phosphorylation, indicating that APPL1 sensitizes insulin signaling by acting at a site downstream of the IR. Our study uncovers a mechanism regulating insulin signaling and crosstalk between the insulin and adiponectin pathways. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  9. Interleukin (IL) 36 gamma induces mucin 5AC, oligomeric mucus/gel-forming expression via IL-36 receptor-extracellular signal regulated kinase 1 and 2, and p38-nuclear factor kappa-light-chain-enhancer of activated B cells in human airway epithelial cells.

    Science.gov (United States)

    Bae, Chang Hoon; Choi, Yoon Seok; Na, Hyung Gyun; Song, Si-Youn; Kim, Yong-Dae

    2018-03-01

    Mucin 5AC, oligomeric mucus/gel-forming (MUC5AC) expression is significantly increased in allergic and inflammatory airway diseases. Interleukin (IL) 36 gamma is predominantly expressed in airway epithelial cells and plays an important role in innate and adaptive immune responses. IL-36 gamma is induced by many inflammatory mediators, including cytokines and bacterial and viral infections. However, the association between IL-36 gamma and mucin secretion in human airway epithelial cells has not yet been fully investigated. The objective of this study was to determine whether IL-36 gamma might play a role in the regulation of mucin secretion in airway epithelial cells. We investigated the effect and brief signaling pathway of IL-36 gamma on MUC5AC expression in human airway epithelial cells. Enzyme immunoassay, immunoblot analysis, immunofluorescence staining, reverse transcriptase-polymerase chain reaction (PCR), and real-time PCR were performed in mucin-producing human airway epithelial NCI-H292 cells and in human nasal epithelial cells after pretreatment with IL-36 gamma, several specific inhibitors, or small interfering RNAs (siRNA). IL-36 gamma induced MUC5AC expression and activated the phosphorylation of extracellular signal regulated kinase (ERK) 1 and 2, p38, and nuclear factor-kappa-light-chain-enhancer of activated B cells (NF-kappa B). IL-36 receptor antagonist significantly attenuated these effects. The specific inhibitor and siRNA of ERK1, ERK2, p38, and NF-kappa B significantly attenuated IL-36 gamma induced MUC5AC expression. These results indicated that IL-36 gamma induced MUC5AC expression via the IL-36 receptor-mediated ERK1/2 and p38/NF-kappa B pathway in human airway epithelial cells.

  10. Unraveling a phosphorylation event in a folded protein by NMR spectroscopy: phosphorylation of the Pin1 WW domain by PKA

    International Nuclear Information System (INIS)

    Smet-Nocca, Caroline; Launay, Hélène; Wieruszeski, Jean-Michel; Lippens, Guy; Landrieu, Isabelle

    2013-01-01

    The Pin1 protein plays a critical role in the functional regulation of the hyperphosphorylated neuronal Tau protein in Alzheimer’s disease and is by itself regulated by phosphorylation. We have used Nuclear Magnetic Resonance (NMR) spectroscopy to both identify the PKA phosphorylation site in the Pin1 WW domain and investigate the functional consequences of this phosphorylation. Detection and identification of phosphorylation on serine/threonine residues in a globular protein, while mostly occurring in solvent-exposed flexible loops, does not lead to chemical shift changes as obvious as in disordered proteins and hence does not necessarily shift the resonances outside the spectrum of the folded protein. Other complications were encountered to characterize the extent of the phosphorylation, as part of the 1 H, 15 N amide resonances around the phosphorylation site are specifically broadened in the unphosphorylated state. Despite these obstacles, NMR spectroscopy was an efficient tool to confirm phosphorylation on S16 of the WW domain and to quantify the level of phosphorylation. Based on this analytical characterization, we show that WW phosphorylation on S16 abolishes its binding capacity to a phosphorylated Tau peptide. A reduced conformational heterogeneity and flexibility of the phospho-binding loop upon S16 phosphorylation could account for part of the decreased affinity for its phosphorylated partner. Additionally, a structural model of the phospho-WW obtained by molecular dynamics simulation and energy minimization suggests that the phosphate moiety of phospho-S16 could compete with the phospho-substrate.

  11. Modulator effects of interleukin-1beta and tumor necrosis factor-alpha on AMPA-induced excitotoxicity in mouse organotypic hippocampal slice cultures

    DEFF Research Database (Denmark)

    Bernardino, Liliana; Xapelli, Sara; Silva, Ana P

    2005-01-01

    The inflammatory cytokines interleukin-1beta and tumor necrosis factor-alpha (TNF-alpha) have been identified as mediators of several forms of neurodegeneration in the brain. However, they can produce either deleterious or beneficial effects on neuronal function. We investigated the effects...... of mouse recombinant TNF-alpha (10 ng/ml) enhanced excitotoxicity when the cultures were simultaneously exposed to AMPA and to this cytokine. Decreasing the concentration of TNF-alpha to 1 ng/ml resulted in neuroprotection against AMPA-induced neuronal death independently on the application protocol....... By using TNF-alpha receptor (TNFR) knock-out mice, we demonstrated that the potentiation of AMPA-induced toxicity by TNF-alpha involves TNF receptor-1, whereas the neuroprotective effect is mediated by TNF receptor-2. AMPA exposure was associated with activation and proliferation of microglia as assessed...

  12. NMDA receptor adjusted co-administration of ecstasy and cannabinoid receptor-1 agonist in the amygdala via stimulation of BDNF/Trk-B/CREB pathway in adult male rats.

    Science.gov (United States)

    Ashabi, Ghorbangol; Sadat-Shirazi, Mitra-Sadat; Khalifeh, Solmaz; Elhampour, Laleh; Zarrindast, Mohammad-Reza

    2017-04-01

    Consumption of cannabinoid receptor-1 (CB-1) agonist such as cannabis is widely taken in 3,4- methylenedioxymethamphetamine (MDMA) or ecstasy users; it has been hypothesized that co-consumption of CB-1 agonist might protect neurons against MDMA toxicity. N-methyl-d-aspartate (NMDA) receptors regulate neuronal plasticity and firing rate in the brain through Tyrosine-kinase B (Trk-B) activation. The molecular and electrophysiological association among NMDA and MDMA/Arachidonylcyclopropylamide (ACPA, a selective CB-1 receptor agonist) co-consumption was not well-known. Here, neuronal spontaneous activity, Brain-derived neurotrophic factor (BDNF), Trk-B and cAMP response element binding protein (CREB) phosphorylation levels were recognized in ACPA and MDMA co-injected rats. Besides, we proved the role of NMDA receptor on MDMA and ACPA combination on neuronal spontaneous activity and Trk-B/BDNF pathway in the central amygdala (CeA). Male rats were anesthetized with intra-peritoneal injections of urethane; MDMA, D-2-amino-5-phosphonopentanoate (D-AP5, NMDA receptor antagonist) were injected into CeA. ACPA was administrated by intra-cerebroventricular injection. Thirty minutes following injections, neuronal firing rate was recorded from CeA. Two hours after drug injection, amygdala was collected from brain for molecular evaluations. Single administration of MDMA and/or ACPA reduced firing rates compared with sham group in the CeA dose-dependently. Injection of D-AP5, ACPA and MDMA reduced firing rate compared with sham group (P<0.001). Interestingly, injection of ACPA+MDMA enhanced BDNF, Trk-B and CREB phosphorylation compared with MDMA groups. D-AP5, ACPA and MDMA co-injection decreased BDNF, Trk-B and CREB phosphorylation levels compared with ACPA+MDMA in the amygdala (P<0.01). Probably, NMDA receptors are involved in the protective role of acute MDMA+ACPA co-injection via BDNF/Trk-B/CREB pathways. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Glucocorticoid up-regulation of high-affinity interleukin 6 receptors on human epithelial cells

    International Nuclear Information System (INIS)

    Snyers, L.; De Wit, L.; Content, J.

    1990-01-01

    Interleukin 6 (IL-6) is a potent pleiotropic cytokine, known, among others, to stimulate immunoglobulin production by B cells and to trigger acute-phase protein synthesis by hepatocytes. Similar to IL-1, it is produced by monocytes and macrophages following an inflammatory challenge. Analysis of IL-6 receptor (IL-6R) expression on different human cell lines indicates that dexamethasone could up-regulate the number of IL-6R on one epithelial cell line (UAC) and on two hepatoma cell lines (HepG2 and Hep3B). This effect was confirmed by Scatchard analysis of binding experiments, using [ 35 S]methionine and [ 35 S]cysteine metabolically labeled IL-6. It was confirmed at the level of mRNA expression by Northern blot analysis. These results provide evidence for a link between IL-6 and glucocorticoids. They could represent an example of a system in which one role of glucocorticoids is to define more accurately the target of cytokines, and they could explain, at least partly, the frequently observed synergy between IL-6 and glucocorticoids, notably in the case of hepatocytes

  14. Unraveling a phosphorylation event in a folded protein by NMR spectroscopy: phosphorylation of the Pin1 WW domain by PKA

    Energy Technology Data Exchange (ETDEWEB)

    Smet-Nocca, Caroline, E-mail: caroline.smet@univ-lille1.fr; Launay, Helene; Wieruszeski, Jean-Michel; Lippens, Guy; Landrieu, Isabelle, E-mail: isabelle.landrieu@univ-lille1.fr [Universite de Lille-Nord de France, Institut Federatif de Recherches 147, CNRS UMR 8576 (France)

    2013-04-15

    The Pin1 protein plays a critical role in the functional regulation of the hyperphosphorylated neuronal Tau protein in Alzheimer's disease and is by itself regulated by phosphorylation. We have used Nuclear Magnetic Resonance (NMR) spectroscopy to both identify the PKA phosphorylation site in the Pin1 WW domain and investigate the functional consequences of this phosphorylation. Detection and identification of phosphorylation on serine/threonine residues in a globular protein, while mostly occurring in solvent-exposed flexible loops, does not lead to chemical shift changes as obvious as in disordered proteins and hence does not necessarily shift the resonances outside the spectrum of the folded protein. Other complications were encountered to characterize the extent of the phosphorylation, as part of the {sup 1}H,{sup 15}N amide resonances around the phosphorylation site are specifically broadened in the unphosphorylated state. Despite these obstacles, NMR spectroscopy was an efficient tool to confirm phosphorylation on S16 of the WW domain and to quantify the level of phosphorylation. Based on this analytical characterization, we show that WW phosphorylation on S16 abolishes its binding capacity to a phosphorylated Tau peptide. A reduced conformational heterogeneity and flexibility of the phospho-binding loop upon S16 phosphorylation could account for part of the decreased affinity for its phosphorylated partner. Additionally, a structural model of the phospho-WW obtained by molecular dynamics simulation and energy minimization suggests that the phosphate moiety of phospho-S16 could compete with the phospho-substrate.

  15. The Plant Leucine-Rich Repeat Receptor-Like Kinase PSY1R from Head to Toe

    DEFF Research Database (Denmark)

    Oehlenschlæger, Christian Berg

    PSY1R belongs to the family of plant leucine-rich repeat receptor-like kinases that play important roles in processes such as growth regulation and plant immunity response. PSY1R was proposed to be the receptor of the plant peptide hormone PSY1 which promotes cell expansion. PSY1R was furthermore...... is activated. This work provides the first study of the direct interaction between PSY1R and the peptide ligand PSY1. The binding was evaluated both for full length PSY1R expressed in plants and for the isolated extracellular domain expressed in insect cells. PSY1 binds to the extracellular domain of PSY1R...... shown to phosphorylate and regulate the activity of the plasma membrane localized H+-ATPase, AHA2. While the mechanism of PSY1R-mediated AHA2 phosphorylation has previously been studied in detail, little is known about how PSY1R binds PSY1 peptide ligand and how the intracellular PSY1R kinase domain...

  16. The selective phosphorylation of a guanine nucleotide-binding regulatory protein

    International Nuclear Information System (INIS)

    Carlson, K.E.

    1989-01-01

    Receptor-activated signal transduction pathways regulate the responsiveness of cells to external stimuli. These transduction pathways themselves are subject to regulation, most commonly by phosphorylation. Guanine nucleotide-binding regulatory proteins (G Proteins), as requisite signal transducing elements for many plasma membrane receptors, are considered likely targets for regulation by phosphorylation. Protein kinase C (PKC) has been shown to phosphorylate the α subunit of G i and other G proteins in solution. However, the occurrence of the phosphorylation of G 1 within intact cells in response to activation of PKC has not been rigorously demonstrated. In this thesis, the extent to which the α subunits of G i undergo phosphorylation within human platelets in response to activation of PKC was examined by means of radiolabeling and immunoprecipitation. Incubation of platelets with phorbol-12-myristate-13-acetate (PMA), a potent activator of PKC, promoted the phosphorylation of several proteins within saponin-permeabilized and intact platelets incubated with [γ 32 P]ATP and [ 32 P]H 3 PO 4 , respectively. None of the phosphoproteins, however, were precipitated by either of two antisera containing antibodies differing in specificities for epitopes within G iα -despite precipitation of a substantial fraction of the subunit itself. In contrast, other antisera, containing antibodies specific for the recently describe G zα , or antibodies for both G zα and G iα , precipitated a 40-kDa phosphoprotein

  17. Rat1p maintains RNA polymerase II CTD phosphorylation balance

    DEFF Research Database (Denmark)

    Jimeno-González, Silvia; Schmid, Manfred; Malagon, Francisco

    2014-01-01

    . Here we describe a function of Rat1p in regulating phosphorylation levels of the C-terminal domain (CTD) of the largest RNAPII subunit, Rpb1p, during transcription elongation. The rat1-1 mutant exhibits highly elevated levels of CTD phosphorylation as well as RNAPII distribution and transcription...... termination defects. These phenotypes are all rescued by overexpression of the CTD phosphatase Fcp1p, suggesting a functional relationship between the absence of Rat1p activity, elevated CTD phosphorylation, and transcription defects. We also demonstrate that rat1-1 cells display increased RNAPII...

  18. Agonist-induced internalisation of the glucagon-like peptide-1 receptor is mediated by the Gαq pathway.

    Science.gov (United States)

    Thompson, Aiysha; Kanamarlapudi, Venkateswarlu

    2015-01-01

    The glucagon-like peptide-1 receptor (GLP-1R) is a G-protein-coupled receptor (GPCR) and an important target in the treatment of type 2 diabetes mellitus (T2DM). Upon stimulation with agonist, the GLP-1R signals through both Gαs and Gαq coupled pathways to stimulate insulin secretion. The agonist-induced GLP-1R internalisation has recently been shown to be important for insulin secretion. However, the molecular mechanisms underlying GLP-1R internalisation remain unknown. The aim of this study was to determine the role of GLP-1R downstream signalling pathways in its internalisation. Agonist-induced human GLP-1R (hGLP-1R) internalisation and activity were examined using a number of techniques including immunoblotting, ELISA, immunofluorescence and luciferase assays to determine cAMP production, intracellular Ca(2+) accumulation and ERK phosphorylation. Agonist-induced hGLP-1R internalisation is dependent on caveolin-1 and dynamin. Inhibition of the Gαq pathway but not the Gαs pathway affected hGLP-1R internalisation. Consistent with this, hGLP-1R mutant T149M and small-molecule agonists (compound 2 and compound B), which activate only the Gαs pathway, failed to induce internalisation of the receptor. Chemical inhibitors of the Gαq pathway, PKC and ERK phosphorylation significantly reduced agonist-induced hGLP-1R internalisation. These inhibitors also suppressed agonist-induced ERK1/2 phosphorylation demonstrating that the phosphorylated ERK acts downstream of the Gαq pathway in the hGLP-1R internalisation. In summary, agonist-induced hGLP-1R internalisation is mediated by the Gαq pathway. The internalised hGLP-1R stimulates insulin secretion from pancreatic β-cells, indicating the importance of GLP-1 internalisation for insulin secretion. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Variation in melatonin receptors (Mel(1a) and Mel(1b)) and androgen receptor (AR) expression in the spleen of a seasonally breeding bird, Perdicula asiatica.

    Science.gov (United States)

    Yadav, S K; Haldar, C; Singh, S S

    2011-12-01

    Daily variation in the peripheral level of melatonin plays a major role in integrating reproduction and environmental information for seasonally breeding birds. However, the variation in immunity and reproduction has never been assessed in any avian species on a 24 h time scale. Therefore, to understand the relationship between immune function and reproductive phases in a seasonally breeding bird, Perdicula asiatica, the Indian jungle bush quail, we studied the daily variation of melatonin and testosterone levels along with expression of their receptors Mel(1a), Mel(1b), and androgen receptor in the spleen during the reproductively active phase. Immunocytochemistry for the melatonin receptors Mel(1a) and Mel(1b) presented a differential distribution pattern. Western blot of splenic protein suggested a daily rhythm of melatonin receptors, while acrophases for the two melatonin receptors Mel(1a) and Mel(1b) differed by 4 h, suggesting that the expression of the receptors may peak at different times, causing more of either Mel(1a) or Mel(1b) to be available at a particular time to mediate function. The circulatory melatonin level correlated with percentage stimulation ratio of splenocytes and plasma interleukin-2 level, but did not correlate with testosterone or androgen receptor, suggesting that melatonin could be a major hormone imparting a time-of-day effect on the modulation of immune function in a seasonally breeding bird during the reproductively active phase. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Primary Blast-Induced Changes in Akt and GSK3β Phosphorylation in Rat Hippocampus

    Directory of Open Access Journals (Sweden)

    Yushan Wang

    2017-08-01

    Full Text Available Traumatic brain injury (TBI due to blast from improvised explosive devices has been a leading cause of morbidity and mortality in recent conflicts in Iraq and Afghanistan. However, the mechanisms of primary blast-induced TBI are not well understood. The Akt signal transduction pathway has been implicated in various brain pathologies including TBI. In the present study, the effects of simulated primary blast waves on the phosphorylation status of Akt and its downstream effector kinase, glycogen synthase kinase 3β (GSK3β, in rat hippocampus, were investigated. Male Sprague-Dawley (SD rats (350–400 g were exposed to a single pulse shock wave (25 psi; ~7 ms duration and sacrificed 1 day, 1 week, or 6 weeks after exposure. Total and phosphorylated Akt, as well as phosphorylation of its downstream effector kinase GSK3β (at serine 9, were detected with western blot analysis and immunohistochemistry. Results showed that Akt phosphorylation at both serine 473 and threonine 308 was increased 1 day after blast on the ipsilateral side of the hippocampus, and this elevation persisted until at least 6 weeks postexposure. Similarly, phosphorylation of GSK3β at serine 9, which inhibits GSK3β activity, was also increased starting at 1 day and persisted until at least 6 weeks after primary blast on the ipsilateral side. In contrast, p-Akt was increased at 1 and 6 weeks on the contralateral side, while p-GSK3β was increased 1 day and 1 week after primary blast exposure. No significant changes in total protein levels of Akt and GSK were observed on either side of the hippocampus at any time points. Immunohistochemical results showed that increased p-Akt was mainly of neuronal origin in the CA1 region of the hippocampus and once phosphorylated, the majority was translocated to the dendritic and plasma membranes. Finally, electrophysiological data showed that evoked synaptic N-methyl-d-aspartate (NMDA receptor activity was

  1. Selective inhibition reveals cyclin-dependent kinase 2 as another kinase that phosphorylates the androgen receptor at serine 81

    Czech Academy of Sciences Publication Activity Database

    Jorda, Radek; Bučková, Zuzana; Řezníčková, Eva; Bouchal, J.; Kryštof, Vladimír

    2018-01-01

    Roč. 1865, č. 2 (2018), s. 354-363 ISSN 0167-4889 R&D Projects: GA MŠk(CZ) LO1204; GA MŠk(CZ) LO1304 Institutional support: RVO:61389030 Keywords : Androgen receptor * Cyclin-dependent kinase * Inhibitor * Phosphorylation * Serine 81 Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 4.521, year: 2016

  2. Internalisation of the protease-activated receptor 1: role of the third intracellular loop and of the cytoplasmic tail.

    Science.gov (United States)

    Chen, X; Berrou, J; Vigneau, C; Delarue, F; Rondeau, E

    2001-06-01

    To analyse the mechanisms of PAR-1 internalisation, we constructed several PAR-1 mutants and stably expressed them in CHO cells. Our study shows that the Ser(306)-->Ala mutation (S306A), which eliminates a potential site of phosphorylation by PKC in the third intracellular loop of PAR-1, did not change the rate of phosphorylation but reduced the rate of thrombin-induced internalisation of the PAR-1 mutant (58 versus 78% of membrane PAR-1 in 15 min, pinternalisation upon activation. This deletion also inhibited the PMA-induced and the agonist-independent internalisation of the receptor. The Tyr(371)--> Ala mutation (Y371A), in a NPXXY motif of the seventh transmembrane domain of the receptor had no effect on the receptor behaviour. Our results indicate that both the C-tail and the third intracellular loop are involved in PAR-1 internalisation induced by thrombin while only the C-tail plays a role in the PMA-induced and in the agonist-independent PAR-1 internalisation.

  3. Overexpression of interleukin-1β and interferon-γ in type I thoracic aortic dissections and ascending thoracic aortic aneurysms: possible correlation with matrix metalloproteinase-9 expression and apoptosis of aortic media cells.

    Science.gov (United States)

    Zhang, Lei; Liao, Ming-fang; Tian, Lei; Zou, Si-li; Lu, Qing-sheng; Bao, Jun-min; Pei, Yi-fei; Jing, Zai-ping

    2011-07-01

    To examine the expression of interleukin-1β and interferon-γ and their possible roles in aortic dissections and aneurysms. Aortic specimens were obtained from patients with type I thoracic aortic dissection, ascending thoracic aortic aneurysms, and control organ donors. The expression of interleukin-1β, interferon-γ, matrix metalloproteinase-9, and signal transduction factors phospho-p38 and phosphorylated c-jun N-terminal kinase (phospho-JNK) were detected by real time reverse transcription-polymerase chain reaction (real time RT-PCR), Western blot, and immunohistochemistry, respectively. Terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining was performed to detect apoptosis of media cells. The correlation of these factors and apoptosis was also studied. Apoptosis in the media of thoracic aortic dissection and in ascending thoracic aortic aneurysms was dramatically higher than in the control group. The expression of interleukin-1β gradually increased from the control group, thoracic aortic dissection to ascending thoracic aortic aneurysms (p matrix metalloproteinase-9 was significantly increased in the media of thoracic aortic dissection and ascending thoracic aortic aneurysms compared with the control group (p correlations between interleukin-1β versus matrix metalloproteinase-9, interleukin-1β versus phospho-p38 in thoracic aortic dissection (p matrix metalloproteinase-9, interferon-γ versus phospho-JNK, interferon-γ versus apoptosis, and interleukin-1β versus apoptosis in ascending thoracic aortic aneurysms (p = 0.02, 0.02, p matrix metalloproteinase-9 and the apoptosis of media cells in humans. Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.

  4. Deficiency of Lipoprotein Lipase in Neurons Decreases AMPA Receptor Phosphorylation and Leads to Neurobehavioral Abnormalities in Mice.

    Directory of Open Access Journals (Sweden)

    Tian Yu

    Full Text Available Alterations in lipid metabolism have been found in several neurodegenerative disorders, including Alzheimer's disease. Lipoprotein lipase (LPL hydrolyzes triacylglycerides in lipoproteins and regulates lipid metabolism in multiple organs and tissues, including the central nervous system (CNS. Though many brain regions express LPL, the functions of this lipase in the CNS remain largely unknown. We developed mice with neuron-specific LPL deficiency that became obese on chow by 16 wks in homozygous mutant mice (NEXLPL-/- and 10 mo in heterozygous mice (NEXLPL+/-. In the present study, we show that 21 mo NEXLPL+/- mice display substantial cognitive function decline including poorer learning and memory, and increased anxiety with no difference in general motor activities and exploratory behavior. These neurobehavioral abnormalities are associated with a reduction in the 2-amino-3-(3-hydroxy-5-methyl-isoxazol-4-yl propanoic acid (AMPA receptor subunit GluA1 and its phosphorylation, without any alterations in amyloid β accumulation. Importantly, a marked deficit in omega-3 and omega-6 polyunsaturated fatty acids (PUFA in the hippocampus precedes the development of the neurobehavioral phenotype of NEXLPL+/- mice. And, a diet supplemented with n-3 PUFA can improve the learning and memory of NEXLPL+/- mice at both 10 mo and 21 mo of age. We interpret these findings to indicate that LPL regulates the availability of PUFA in the CNS and, this in turn, impacts the strength of synaptic plasticity in the brain of aging mice through the modification of AMPA receptor and its phosphorylation.

  5. Interleukin-17 retinotoxicity is prevented by gene transfer of a soluble interleukin-17 receptor acting as a cytokine blocker: implications for age-related macular degeneration.

    Directory of Open Access Journals (Sweden)

    Daniel Ardeljan

    Full Text Available Age-related macular degeneration (AMD is a common yet complex retinal degeneration that causes irreversible central blindness in the elderly. Pathology is widely believed to follow loss of retinal pigment epithelium (RPE and photoreceptor degeneration. Here we report aberrant expression of interleukin-17A (IL17A and the receptor IL17RC in the macula of AMD patients. In vitro, IL17A induces RPE cell death characterized by the accumulation of cytoplasmic lipids and autophagosomes with subsequent activation of pro-apoptotic Caspase-3 and Caspase-9. This pathology is reduced by siRNA knockdown of IL17RC. IL17-dependent retinal degeneration in a mouse model of focal retinal degeneration can be prevented by gene therapy with adeno-associated virus vector encoding soluble IL17 receptor. This intervention rescues RPE and photoreceptors in a MAPK-dependent process. The IL17 pathway plays a key role in RPE and photoreceptor degeneration and could hold therapeutic potential in AMD.

  6. Insulin rapidly stimulates phosphorylation of a 46-kDa membrane protein on tyrosine residues as well as phosphorylation of several soluble proteins in intact fat cells

    International Nuclear Information System (INIS)

    Haering, H.U.; White, M.F.; Machicao, F.; Ermel, B.; Schleicher, E.; Obermaier, B.

    1987-01-01

    It is speculated that the transmission of an insulin signal across the plasma membrane of cells occurs through activation of the tyrosine-specific receptor kinase, autophosphorylation of the receptor, and subsequent phosphorylation of unidentified substrates in the cell. In an attempt to identify possible substrates, the authors labeled intact rat fat cells with [ 32 P]orthophosphate and used an antiphosphotyrosine antibody to identify proteins that become phosphorylated on tyrosine residues in an insulin-stimulated way. In the membrane fraction of the fat cells, they found, in addition to the 95-kDa β-subunit of the receptor, a 46-kDa phosphoprotein that is phosphorylated exclusively on tyrosine residues. This protein is not immunoprecipitated by antibodies against different regions of the insulin receptor and its HPLC tryptic peptide map is different from the tryptic peptide map of the insulin receptor, suggesting that it is not derived from the receptor β-subunit. Insulin stimulates the tyrosine phosphorylation of the 46-kDa protein within 150 sec in the intact cell 3- to 4-fold in a dose-dependent way at insulin concentrations between 0.5 nM and 100 nM. Insulin (0.5 nM, 100 nM) stimulated within 2 min the 32 P incorporation into a 116-kDa band, a 62 kDa band, and three bands between 45 kDa and 50 kDa 2- to 10-fold. They suggest that the 46-kDa membrane protein and possibly also the soluble proteins are endogenous substrates of the receptor tyrosine kinase in fat cells and that their phosphorylation is an early step in insulin signal transmission

  7. PTH1 receptor is involved in mediating cellular response to long-chain polyunsaturated fatty acids.

    Directory of Open Access Journals (Sweden)

    Jose Candelario

    Full Text Available The molecular pathways by which long chain polyunsaturated fatty acids (LCPUFA influence skeletal health remain elusive. Both LCPUFA and parathyroid hormone type 1 receptor (PTH1R are known to be involved in bone metabolism while any direct link between the two is yet to be established. Here we report that LCPUFA are capable of direct, PTH1R dependent activation of extracellular ligand-regulated kinases (ERK. From a wide range of fatty acids studied, varying in chain length, saturation, and position of double bonds, eicosapentaenoic (EPA and docosahexaenoic fatty acids (DHA caused the highest ERK phosphorylation. Moreover, EPA potentiated the effect of parathyroid hormone (PTH(1-34 in a superagonistic manner. EPA or DHA dependent ERK phosphorylation was inhibited by the PTH1R antagonist and by knockdown of PTH1R. Inhibition of PTH1R downstream signaling molecules, protein kinases A (PKA and C (PKC, reduced EPA and DHA dependent ERK phosphorylation indicating that fatty acids predominantly activate G-protein pathway and not the β-arrestin pathway. Using picosecond time-resolved fluorescence microscopy and a genetically engineered PTH1R sensor (PTH-CC, we detected conformational responses to EPA similar to those caused by PTH(1-34. PTH1R antagonist blocked the EPA induced conformational response of the PTH-CC. Competitive binding studies using fluorescence anisotropy technique showed that EPA and DHA competitively bind to and alter the affinity of PTH1 receptor to PTH(1-34 leading to a superagonistic response. Finally, we showed that EPA stimulates protein kinase B (Akt phosphorylation in a PTH1R-dependent manner and affects the osteoblast survival pathway, by inhibiting glucocorticoid-induced cell death. Our findings demonstrate for the first time that LCPUFAs, EPA and DHA, can activate PTH1R receptor at nanomolar concentrations and consequently provide a putative molecular mechanism for the action of fatty acids in bone.

  8. Cdk1 Restrains NHEJ through Phosphorylation of XRCC4-like Factor Xlf1

    Directory of Open Access Journals (Sweden)

    Pierre Hentges

    2014-12-01

    Full Text Available Eukaryotic cells use two principal mechanisms for repairing DNA double-strand breaks (DSBs: homologous recombination (HR and nonhomologous end-joining (NHEJ. DSB repair pathway choice is strongly regulated during the cell cycle. Cyclin-dependent kinase 1 (Cdk1 activates HR by phosphorylation of key recombination factors. However, a mechanism for regulating the NHEJ pathway has not been established. Here, we report that Xlf1, a fission yeast XLF ortholog, is a key regulator of NHEJ activity in the cell cycle. We show that Cdk1 phosphorylates residues in the C terminus of Xlf1 over the course of the cell cycle. Mutation of these residues leads to the loss of Cdk1 phosphorylation, resulting in elevated levels of NHEJ repair in vivo. Together, these data establish that Xlf1 phosphorylation by Cdc2Cdk1 provides a molecular mechanism for downregulation of NHEJ in fission yeast and indicates that XLF is a key regulator of end-joining processes in eukaryotic organisms.

  9. Stat1 phosphorylation determines Ras oncogenicity by regulating p27 kip1.

    Directory of Open Access Journals (Sweden)

    Shuo Wang

    Full Text Available Inactivation of p27 Kip1 is implicated in tumorigenesis and has both prognostic and treatment-predictive values for many types of human cancer. The transcription factor Stat1 is essential for innate immunity and tumor immunosurveillance through its ability to act downstream of interferons. Herein, we demonstrate that Stat1 functions as a suppressor of Ras transformation independently of an interferon response. Inhibition of Ras transformation and tumorigenesis requires the phosphorylation of Stat1 at tyrosine 701 but is independent of Stat1 phosphorylation at serine 727. Stat1 induces p27 Kip1 expression in Ras transformed cells at the transcriptional level through mechanisms that depend on Stat1 phosphorylation at tyrosine 701 and activation of Stat3. The tumor suppressor properties of Stat1 in Ras transformation are reversed by the inactivation of p27 Kip1. Our work reveals a novel functional link between Stat1 and p27 Kip1, which act in coordination to suppress the oncogenic properties of activated Ras. It also supports the notion that evaluation of Stat1 phosphorylation in human tumors may prove a reliable prognostic factor for patient outcome and a predictor of treatment response to anticancer therapies aimed at activating Stat1 and its downstream effectors.

  10. ABA renewal involves enhancements in both GluA2-lacking AMPA receptor activity and GluA1 phosphorylation in the lateral amygdala.

    Directory of Open Access Journals (Sweden)

    Kyungjoon Park

    Full Text Available Fear renewal, the context-specific relapse of fear following fear extinction, is a leading animal model of post-traumatic stress disorders (PTSD and fear-related disorders. Although fear extinction can diminish fear responses, this effect is restricted to the context where the extinction is carried out, and the extinguished fear strongly relapses when assessed in the original acquisition context (ABA renewal or in a context distinct from the conditioning and extinction contexts (ABC renewal. We have previously identified Ser831 phosphorylation of GluA1 subunit in the lateral amygdala (LA as a key molecular mechanism for ABC renewal. However, molecular mechanisms underlying ABA renewal remain to be elucidated. Here, we found that both the excitatory synaptic efficacy and GluA2-lacking AMPAR activity at thalamic input synapses onto the LA (T-LA synapses were enhanced upon ABA renewal. GluA2-lacking AMPAR activity was also increased during low-threshold potentiation, a potential cellular substrate of renewal, at T-LA synapses. The microinjection of 1-naphtylacetyl-spermine (NASPM, a selective blocker of GluA2-lacking AMPARs, into the LA attenuated ABA renewal, suggesting a critical role of GluA2-lacking AMPARs in ABA renewal. We also found that Ser831 phosphorylation of GluA1 in the LA was increased upon ABA renewal. We developed a short peptide mimicking the Ser831-containing C-tail region of GluA1, which can be phosphorylated upon renewal (GluA1S; thus, the phosphorylated GluA1S may compete with Ser831-phosphorylated GluA1. This GluA1S peptide blocked the low-threshold potentiation when dialyzed into a recorded neuron. The microinjection of a cell-permeable form of GluA1S peptide into the LA attenuated ABA renewal. In support of the GluA1S experiments, a GluA1D peptide (in which the serine at 831 is replaced with a phosphomimetic amino acid, aspartate attenuated ABA renewal when microinjected into the LA. These findings suggest that enhancements

  11. ABA renewal involves enhancements in both GluA2-lacking AMPA receptor activity and GluA1 phosphorylation in the lateral amygdala.

    Science.gov (United States)

    Park, Kyungjoon; Song, Beomjong; Kim, Jeongyeon; Hong, Ingie; Song, Sangho; Lee, Junuk; Park, Sungmo; Kim, Jihye; An, Bobae; Lee, Hyun Woo; Lee, Seungbok; Kim, Hyun; Lee, Justin C; Lee, Sukwon; Choi, Sukwoo

    2014-01-01

    Fear renewal, the context-specific relapse of fear following fear extinction, is a leading animal model of post-traumatic stress disorders (PTSD) and fear-related disorders. Although fear extinction can diminish fear responses, this effect is restricted to the context where the extinction is carried out, and the extinguished fear strongly relapses when assessed in the original acquisition context (ABA renewal) or in a context distinct from the conditioning and extinction contexts (ABC renewal). We have previously identified Ser831 phosphorylation of GluA1 subunit in the lateral amygdala (LA) as a key molecular mechanism for ABC renewal. However, molecular mechanisms underlying ABA renewal remain to be elucidated. Here, we found that both the excitatory synaptic efficacy and GluA2-lacking AMPAR activity at thalamic input synapses onto the LA (T-LA synapses) were enhanced upon ABA renewal. GluA2-lacking AMPAR activity was also increased during low-threshold potentiation, a potential cellular substrate of renewal, at T-LA synapses. The microinjection of 1-naphtylacetyl-spermine (NASPM), a selective blocker of GluA2-lacking AMPARs, into the LA attenuated ABA renewal, suggesting a critical role of GluA2-lacking AMPARs in ABA renewal. We also found that Ser831 phosphorylation of GluA1 in the LA was increased upon ABA renewal. We developed a short peptide mimicking the Ser831-containing C-tail region of GluA1, which can be phosphorylated upon renewal (GluA1S); thus, the phosphorylated GluA1S may compete with Ser831-phosphorylated GluA1. This GluA1S peptide blocked the low-threshold potentiation when dialyzed into a recorded neuron. The microinjection of a cell-permeable form of GluA1S peptide into the LA attenuated ABA renewal. In support of the GluA1S experiments, a GluA1D peptide (in which the serine at 831 is replaced with a phosphomimetic amino acid, aspartate) attenuated ABA renewal when microinjected into the LA. These findings suggest that enhancements in both the

  12. Synergistic reversal of type 1 diabetes in NOD mice with anti-CD3 and interleukin-1 blockade

    DEFF Research Database (Denmark)

    Ablamunits, Vitaly; Henegariu, Octavian; Hansen, Jakob Bondo

    2012-01-01

    (ab')(2) fragments of anti-CD3 mAb with or without IL-1 receptor antagonist (IL-1RA), or anti-IL-1ß mAb. We studied the reversal of diabetes and effects of treatment on the immune system. Mice that received a combination of anti-CD3 mAb with IL-1RA showed a more rapid rate of remission of diabetes than......Inflammatory cytokines are involved in autoimmune diabetes: among the most prominent is interleukin (IL)-1ß. We postulated that blockade of IL-1ß would modulate the effects of anti-CD3 monoclonal antibody (mAb) in treating diabetes in NOD mice. To test this, we treated hyperglycemic NOD mice with F...... arginase expression in macrophages and dendritic cells, and had delayed adoptive transfer of diabetes. After 1 month, there were increased concentrations of IgG1 isotype antibodies and reduced intrapancreatic expression of IFN-¿, IL-6, and IL-17 despite normal splenocyte cytokine secretion. These studies...

  13. Effects of intraplantar botulinum toxin-B on carrageenan-induced changes in nociception and spinal phosphorylation of GluA1 and Akt.

    Science.gov (United States)

    Sikandar, Shafaq; Gustavsson, Ynette; Marino, Marc J; Dickenson, Anthony H; Yaksh, Tony L; Sorkin, Linda S; Ramachandran, Roshni

    2016-07-01

    Increasing evidence suggests that botulinum neurotoxins (BoNTs) delivered into the skin and muscle in certain human and animal pain states may exert antinociceptive efficacy though their uptake and transport to central afferent terminals. Cleavage of soluble N-methylaleimide-sensitive attachment protein receptor by BoNTs can impede vesicular mediated neurotransmitter release as well as transport/insertion of channel/receptor subunits into plasma membranes, an effect that can reduce activity-evoked facilitation. Here, we explored the effects of intraplantar botulinum toxin- B (BoNT-B) on peripheral inflammation and spinal nociceptive processing in an inflammatory model of pain. C57BL/6 mice (male) received unilateral intraplantar BoNT (1 U, 30 μL) or saline prior to intraplantar carrageenan (20 μL, 2%) or intrathecal N-methyl-D-aspartate (NMDA), substance P or saline (5 μL). Intraplantar carrageenan resulted in edema and mechanical allodynia in the injected paw and increased phosphorylation of a glutamate subunit (pGluA1ser845) and a serine/threonine-specific protein kinase (pAktser473) in spinal dorsal horn along with an increased incidence of spinal c-Fos positive cells. Pre-treatment with intraplantar BoNT-B reduced carrageenan evoked: (i) allodynia, but not edema; (ii) pGluA1 and pAkt and (iii) c-Fos expression. Further, intrathecal NMDA and substance P each increased dorsal horn levels of pGluA1 and pAkt. Intraplantar BoNT-B inhibited NMDA, but not substance P evoked phosphorylation of GluA1 and Akt. These results suggest that intraplantar toxin is transported centrally to block spinal activation and prevent phosphorylation of a glutamate receptor subunit and a kinase, which otherwise contribute to facilitated states. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  14. mTORC1 Directly Phosphorylates and Regulates Human MAF1

    Science.gov (United States)

    Michels, Annemieke A.; Robitaille, Aaron M.; Buczynski-Ruchonnet, Diane; Hodroj, Wassim; Reina, Jaime H.; Hall, Michael N.; Hernandez, Nouria

    2010-01-01

    mTORC1 is a central regulator of growth in response to nutrient availability, but few direct targets have been identified. RNA polymerase (pol) III produces a number of essential RNA molecules involved in protein synthesis, RNA maturation, and other processes. Its activity is highly regulated, and deregulation can lead to cell transformation. The human phosphoprotein MAF1 becomes dephosphorylated and represses pol III transcription after various stresses, but neither the significance of the phosphorylations nor the kinase involved is known. We find that human MAF1 is absolutely required for pol III repression in response to serum starvation or TORC1 inhibition by rapamycin or Torin1. The protein is phosphorylated mainly on residues S60, S68, and S75, and this inhibits its pol III repression function. The responsible kinase is mTORC1, which phosphorylates MAF1 directly. Our results describe molecular mechanisms by which mTORC1 controls human MAF1, a key repressor of RNA polymerase III transcription, and add a new branch to the signal transduction cascade immediately downstream of TORC1. PMID:20516213

  15. Sphingosine-1-phosphate receptors: Zooming in on ligand-induced intracellular trafficking and its functional implications

    NARCIS (Netherlands)

    Verzijl, Dennis; Peters, Stephan L. M.; Alewijnse, Astrid E.

    2010-01-01

    Regulatory processes including receptor phosphorylation and intracellular trafficking, also referred to as receptor internalization, are important processes to terminate G protein-coupled receptor (GPCR) signaling. Compelling evidence now indicates that internalization of a receptor is not

  16. Molecular Characterisation of Small Molecule Agonists Effect on the Human Glucagon Like Peptide-1 Receptor Internalisation.

    Science.gov (United States)

    Thompson, Aiysha; Stephens, Jeffrey W; Bain, Stephen C; Kanamarlapudi, Venkateswarlu

    2016-01-01

    The glucagon-like peptide receptor (GLP-1R), which is a G-protein coupled receptor (GPCR), signals through both Gαs and Gαq coupled pathways and ERK phosphorylation to stimulate insulin secretion. The aim of this study was to determine molecular details of the effect of small molecule agonists, compounds 2 and B, on GLP-1R mediated cAMP production, intracellular Ca2+ accumulation, ERK phosphorylation and its internalisation. In human GLP-1R (hGLP-1R) expressing cells, compounds 2 and B induced cAMP production but caused no intracellular Ca2+ accumulation, ERK phosphorylation or hGLP-1R internalisation. GLP-1 antagonists Ex(9-39) and JANT-4 and the orthosteric binding site mutation (V36A) in hGLP-1R failed to inhibit compounds 2 and B induced cAMP production, confirming that their binding site distinct from the GLP-1 binding site on GLP-1R. However, K334A mutation of hGLP-1R, which affects Gαs coupling, inhibited GLP-1 as well as compounds 2 and B induced cAMP production, indicating that GLP-1, compounds 2 and B binding induce similar conformational changes in the GLP-1R for Gαs coupling. Additionally, compound 2 or B binding to the hGLP-1R had significantly reduced GLP-1 induced intracellular Ca2+ accumulation, ERK phosphorylation and hGLP-1R internalisation. This study illustrates pharmacology of differential activation of GLP-1R by GLP-1 and compounds 2 and B.

  17. Molecular Characterisation of Small Molecule Agonists Effect on the Human Glucagon Like Peptide-1 Receptor Internalisation.

    Directory of Open Access Journals (Sweden)

    Aiysha Thompson

    Full Text Available The glucagon-like peptide receptor (GLP-1R, which is a G-protein coupled receptor (GPCR, signals through both Gαs and Gαq coupled pathways and ERK phosphorylation to stimulate insulin secretion. The aim of this study was to determine molecular details of the effect of small molecule agonists, compounds 2 and B, on GLP-1R mediated cAMP production, intracellular Ca2+ accumulation, ERK phosphorylation and its internalisation. In human GLP-1R (hGLP-1R expressing cells, compounds 2 and B induced cAMP production but caused no intracellular Ca2+ accumulation, ERK phosphorylation or hGLP-1R internalisation. GLP-1 antagonists Ex(9-39 and JANT-4 and the orthosteric binding site mutation (V36A in hGLP-1R failed to inhibit compounds 2 and B induced cAMP production, confirming that their binding site distinct from the GLP-1 binding site on GLP-1R. However, K334A mutation of hGLP-1R, which affects Gαs coupling, inhibited GLP-1 as well as compounds 2 and B induced cAMP production, indicating that GLP-1, compounds 2 and B binding induce similar conformational changes in the GLP-1R for Gαs coupling. Additionally, compound 2 or B binding to the hGLP-1R had significantly reduced GLP-1 induced intracellular Ca2+ accumulation, ERK phosphorylation and hGLP-1R internalisation. This study illustrates pharmacology of differential activation of GLP-1R by GLP-1 and compounds 2 and B.

  18. Itk tyrosine kinase substrate docking is mediated by a nonclassical SH2 domain surface of PLCgamma1.

    Science.gov (United States)

    Min, Lie; Joseph, Raji E; Fulton, D Bruce; Andreotti, Amy H

    2009-12-15

    Interleukin-2 tyrosine kinase (Itk) is a Tec family tyrosine kinase that mediates signaling processes after T cell receptor engagement. Activation of Itk requires recruitment to the membrane via its pleckstrin homology domain, phosphorylation of Itk by the Src kinase, Lck, and binding of Itk to the SLP-76/LAT adapter complex. After activation, Itk phosphorylates and activates phospholipase C-gamma1 (PLC-gamma1), leading to production of two second messengers, DAG and IP(3). We have previously shown that phosphorylation of PLC-gamma1 by Itk requires a direct, phosphotyrosine-independent interaction between the Src homology 2 (SH2) domain of PLC-gamma1 and the kinase domain of Itk. We now define this docking interface using a combination of mutagenesis and NMR spectroscopy and show that disruption of the Itk/PLCgamma1 docking interaction attenuates T cell signaling. The binding surface on PLCgamma1 that mediates recognition by Itk highlights a nonclassical binding activity of the well-studied SH2 domain providing further evidence that SH2 domains participate in important signaling interactions beyond recognition of phosphotyrosine.

  19. Role of Ubiquitination in IGF-1 Receptor Signaling and Degradation

    OpenAIRE

    Sehat, Bita; Andersson, Sandra; Vasilcanu, Radu; Girnita, Leonard; Larsson, Olle

    2007-01-01

    BACKGROUND: The insulin-like growth factor 1 receptor (IGF-1R) plays numerous crucial roles in cancer biology. The majority of knowledge on IGF-1R signaling is concerned with its role in the activation of the canonical phosphatidyl inositol-3 kinase (PI3K)/Akt and MAPK/ERK pathways. However, the role of IGF-1R ubiquitination in modulating IGF-1R function is an area of current research. In light of this we sought to determine the relationship between IGF-1R phosphorylation, ubiquitination, and...

  20. Radioimmunodetection of human leukemia with anti-interleukin-2 receptor antibody in severe combined immunodeficiency mice

    International Nuclear Information System (INIS)

    Hosono, Makoto; Takaori-Kondo, Akifumi; Zheng-Sheng, Yao; Kobayashi, Hisataka; Hosono, Masako N.; Sakahara, Harumi; Imada, Kazunori; Okuma, Minoru; Uchiyama, Takashi; Konishi, Junji

    1995-01-01

    Anti-Tac monoclonal antibody recognizes human interleukin-2 receptor, which is overexpressed in leukemic cells of most adult T-cell leukemia (ATL) patients. To examine the potency of anti-Tac for targeting of ATL, biodistributions of intravenously administered 125 I- and 111 In-labeled anti-Tac were examined in severe combined immunodeficiency (SCID) mice inoculated with ATL cells. Significant amounts of radiolabeled anti-Tac were found in the spleen and thymus. The trafficking of ATL cells in SCID mice was detected using 111 In-oxine-labeled ATL cells. These results were coincident with the histologically confirmed infiltration of ATL cells. The radiolabeled anti-Tac seemed potent for targeting of ATL

  1. Characterization of interleukin-8 receptors in non-human primates

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, V.; Coto, E.; Gonzalez-Roces, S.; Lopez-Larrea, C. [Hospital Central de Asturias, Oviedo (Spain)] [and others

    1996-09-01

    Interleukin-8 is a chemokine with a potent neutrophil chemoatractant activity. In humans, two different cDNAs encoding human IL8 receptors designated IL8RA and IL8RB have been cloned. IL8RA binds IL8, while IL8RB binds IL8 as well as other {alpha}-chemokines. Both human IL8Rs are encoded by two genes physically linked on chromosome 2. The IL8RA and IL8RB genes have open reading frames (ORF) lacking introns. By direct sequencing of the polymerase chain reaction products, we sequenced the IL8R genes of cell lines from four non-human primates: chimpanzee, gorilla, orangutan, and macaca. The IL8RB encodes an ORF in the four non-human primates, showing 95%-99% similarity to the human IL8RB sequence. The IL8RA homologue in gorilla and chimpanzee consisted of two ORF 98%-99% identical to the human sequence. The macaca and orangutan IL8RA homologues are pseudogenes: a 2 base pair insertion generated a sequence with several stop codons. In addition, we describe the physical linkage of these genes in the four non-human primates and discuss the evolutionary implications of these findings. 25 refs., 5 figs., 3 tabs.

  2. 4PS/insulin receptor substrate (IRS)-2 is the alternative substrate of the insulin receptor in IRS-1-deficient mice.

    Science.gov (United States)

    Patti, M E; Sun, X J; Bruening, J C; Araki, E; Lipes, M A; White, M F; Kahn, C R

    1995-10-20

    Insulin receptor substrate-1 (IRS-1) is the major cytoplasmic substrate of the insulin and insulin-like growth factor (IGF)-1 receptors. Transgenic mice lacking IRS-1 are resistant to insulin and IGF-1, but exhibit significant residual insulin action which corresponds to the presence of an alternative high molecular weight substrate in liver and muscle. Recently, Sun et al. (Sun, X.-J., Wang, L.-M., Zhang, Y., Yenush, L. P., Myers, M. G., Jr., Glasheen, E., Lane, W.S., Pierce, J. H., and White, M. F. (1995) Nature 377, 173-177) purified and cloned 4PS, the major substrate of the IL-4 receptor-associated tyrosine kinase in myeloid cells, which has significant structural similarity to IRS-1. To determine if 4PS is the alternative substrate of the insulin receptor in IRS-1-deficient mice, we performed immunoprecipitation, immunoblotting, and phosphatidylinositol (PI) 3-kinase assays using specific antibodies to 4PS. Following insulin stimulation, 4PS is rapidly phosphorylated in liver and muscle, binds to the p85 subunit of PI 3-kinase, and activates the enzyme. Insulin stimulation also results in the association of 4PS with Grb 2 in both liver and muscle. In IRS-1-deficient mice, both the phosphorylation of 4PS and associated PI 3-kinase activity are enhanced, without an increase in protein expression. Immunodepletion of 4PS from liver and muscle homogenates removes most of the phosphotyrosine-associated PI 3-kinase activity in IRS-1-deficient mice. Thus, 4PS is the primary alternative substrate, i.e. IRS-2, which plays a major role in physiologic insulin signal transduction via both PI 3-kinase activation and Grb 2/Sos association. In IRS-1-deficient mice, 4PS/IRS-2 provides signal transduction to these two major pathways of insulin signaling.

  3. Eicosapentaenoic acid abolishes inhibition of insulin-induced mTOR phosphorylation by LPS via PTP1B downregulation in skeletal muscle.

    Science.gov (United States)

    Wei, Hong-Kui; Deng, Zhao; Jiang, Shu-Zhong; Song, Tong-Xing; Zhou, Yuan-Fei; Peng, Jian; Tao, Ya-Xiong

    2017-01-05

    Dietary n-3 polyunsaturated fatty acids (n-3 PUFAs) increase insulin signaling in skeletal muscle. In the current study, we investigated the effect of eicosapentaenoic acid (EPA) on insulin-induced mammalian target of rapamycin (mTOR) phosphorylation in myotubes. We showed that EPA did not affect basal and insulin-induced mTOR phosphorylation in myotubes. However, EPA abolished lipopolysaccharide (LPS) -induced deficiency in insulin signaling (P  0.05). In myotubes, LPS stimulated PTP1B expression via NF-κB and activation protein-1 (AP1). Pre-incubation of 50 μM EPA prevented the LPS-induced activation of AP1 and NF-κΒ as well as PTP1B expression (P < 0.05). Interestingly, incubation of peroxisome proliferator-activated receptor γ (PPARγ) antagonist (GW9662) prior to EPA treatment, the effect of EPA on insulin-induced mTOR phosphorylation was blocked. Accordingly, EPA did not inhibit the LPS-induced activation of AP1 or NF-κΒ as well as PTP1B expression when incubation of GW9662 prior to EPA treatment. The in vivo study showed that EPA prevented LPS-induced PTPT1B expression and a decrease in insulin-induced mTOR phosphorylation in muscle of mice. In summary, EPA abolished LPS inhibition of insulin-induced mTOR phosphorylation in myotubes, and one of the key mechanisms was to inhibit AP1 and NF-κB activation and PTP1B transcription. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Polymorphism in interleukin-7 receptor α gene is associated with faster CD4 T-cell recovery after initiation of combination antiretroviral therapy

    DEFF Research Database (Denmark)

    Hartling, Hans J; Thørner, Lise W; Erikstrup, Christian

    2014-01-01

    OBJECTIVES: To investigate single-nucleotide polymorphisms (SNPs) in the gene encoding interleukin-7 receptor α (IL7RA) as predictors for CD4⁺ T-cell change after initiation of combination antiretroviral therapy (cART) in HIV-infected whites. DESIGN: SNPs in IL7RA were determined in the Danish HIV...

  5. Serum concentrations of interleukin-1 alpha, interleukin-6 and tumor necrosis factor-alpha in neonatal sepsis and meningitis

    International Nuclear Information System (INIS)

    Fida, Nadia M.; Fadelallah, Mohamed F.; Al-Mughales, Jamil A.

    2006-01-01

    To investigate whether serum levels of interleukin-1alpha (IL-1alpha), IL-6, tumor necrosis factor alpha (TNF-alpha), C-reactive protein (CRP) are useful in the diagnosis of neonatal sepsis and meningitis and differentiate them. Blood samples were collected from 35 full term neonates with suspected infection who admitted to the Neonatology Unit, Pediatric Department, King Abdul-Aziz University Hospital, Jeddah, Saudi Arabia during January 2002 - June 2003. On the basis of laboratory and bacteriological results, newborns were classified into: sepsis (n=28), meningitis (n=7), and healthy controls (n=16). Sepsis groups were further subdivided according to culture results into: group 1 = proven sepsis (n=6), group 2 = clinical sepsis (n=14), and group 3 = possible-infected (n=8). Serum levels of IL-1alpha, IL-6, TNF-alpha were measured using Enzyme-Linked Immunosorbent Assay while CRP by nephelometer: In sepsis and meningitis patients, serum levels of CRP (p<0.01, p<0.05,) and IL-1alpha (p<0.001, p<0.05) were elevated than controls. C-reactive protein levels elevated in proven sepsis (p<0.001) and IL-1alpha elevated in all subgroups of sepsis (groups 1, 2, 3) compared with (p<0.05, p<0.001, p<0.01) controls. Interleukin-6, TNF-alpha showed no significant differences between studied groups. In sepsis and meningitis, IL-1alpha had a highest sensitivity (89%, 86%), and negative predictive values (89% and 93%). Interleukin-1alpha and CRP increased in neonatal sepsis and meningitis, but cannot differentiate between them. Interleukin-1alpha had a highest sensitivity in prediction of neonatal infection and its assessment may improve accuracy of diagnosis. (author)

  6. Essential roles of Gab1 tyrosine phosphorylation in growth factor-mediated signaling and angiogenesis.

    Science.gov (United States)

    Wang, Weiye; Xu, Suowen; Yin, Meimei; Jin, Zheng Gen

    2015-02-15

    Growth factors and their downstream receptor tyrosine kinases (RTKs) mediate a number of biological processes controlling cell function. Adaptor (docking) proteins, which consist exclusively of domains and motifs that mediate molecular interactions, link receptor activation to downstream effectors. Recent studies have revealed that Grb2-associated-binders (Gab) family members (including Gab1, Gab2, and Gab3), when phosphorylated on tyrosine residues, provide binding sites for multiple effector proteins, such as Src homology-2 (SH2)-containing protein tyrosine phosphatase 2 (SHP2) and phosphatidylinositol 3-kinase (PI3K) regulatory subunit p85, thereby playing important roles in transducing RTKs-mediated signals into pathways with diversified biological functions. Here, we provide an up-to-date overview on the domain structure and biological functions of Gab1, the most intensively studied Gab family protein, in growth factor signaling and biological functions, with a special focus on angiogenesis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  7. Elevated insulin-like growth factor 1 receptor signaling induces antiestrogen resistance through the MAPK/ERK and PI3K/Akt signaling routes

    NARCIS (Netherlands)

    Zhang, Y.; Moerkens, M.; Ramaiahgari, S.; Bont, de H.J.G.M.; Price, L.; Meerman, J.H.N.; Water, van de B.

    2011-01-01

    INTRODUCTION: Insulin-like growth factor 1 (IGF-1) receptor (IGF-1R) is phosphorylated in all breast cancer subtypes. Past findings have shown that IGF-1R mediates antiestrogen resistance through cross-talk with estrogen receptor (ER) signaling and via its action upstream of the epidermal growth

  8. The interleukin-20 receptor axis in early rheumatoid arthritis: novel links between disease-associated autoantibodies and radiographic progression

    DEFF Research Database (Denmark)

    Kragstrup, Tue Wenzel; Greisen, Stinne Ravn; Nielsen, Morten Aagaard

    2016-01-01

    BACKGROUND: Rheumatoid arthritis (RA) is often characterized by the presence of rheumatoid factor, anti-citrullinated protein antibodies, and bone erosions. Current therapies can compromise immunity, leading to risk of infection. The interleukin-20 receptor (IL-20R) axis comprising IL-19, IL-20...... the production of the IL-20R cytokines by monocytes/macrophages. Increased baseline plasma concentrations of IL-20 and IL-24 were associated with Sharp-van der Heijde score progression after 24 months (Spearman's rho = 0.19 and 0.26, both P ... by osteoclast precursors and in multinucleated osteoclasts. IL-20 and IL-24 increased the secretion of monocyte chemoattractant protein 1 by these cells. CONCLUSIONS: This study suggests that IL-20 and IL-24 link RA-associated autoantibodies with radiographic progression via the IL-22R1. Modulation of this axis...

  9. Subcellular distribution of cyclin-dependent kinase-like 5 (CDKL5) is regulated through phosphorylation by dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A).

    Science.gov (United States)

    Oi, Ami; Katayama, Syouichi; Hatano, Naoya; Sugiyama, Yasunori; Kameshita, Isamu; Sueyoshi, Noriyuki

    2017-01-08

    Cyclin-dependent kinase-like 5 (CDKL5) is a Ser/Thr protein kinase primarily expressed in the central nervous system and is known to cause X-linked neurodevelopmental disorders such as Rett syndrome. However, the mechanisms regulating CDKL5 have not yet been fully clarified. Therefore, in this study, we investigated the protein kinase that directly phosphorylates CDKL5, identifying it as dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A), an enzyme binding to and phosphorylating CDKL5. We showed that subcellular distribution of CDKL5 was regulated by its phosphorylation by DYRK1A. In mouse neuroblastoma Neuro2a cells, CDKL5 was localized in both the cytosol and nucleus, whereas DYRK1A showed a typical nuclear localization. When CDKL5 and DYRK1A were co-expressed, the cytosolic localization of CDKL5 was significantly increased. Results of site-directed mutagenesis revealed that the phosphorylation site was Ser-308, in the vicinity of the nuclear localization signal. A mutation mimicking the phosphorylated serine residue by aspartate substitution (S308D) changed CDKL5 localization to the cytosol, whereas the corresponding alanine-substituted analog, CDKL5(S308A), was primarily localized to the nucleus. Taken together, these results strongly suggested that DYRK1A bound to CDKL5 and phosphorylated it on Ser-308, thus interfering with its nuclear localization. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. α-MSH stimulates glucose uptake in mouse muscle and phosphorylates Rab-GTPase-activating protein TBC1D1 independently of AMPK

    DEFF Research Database (Denmark)

    Møller, Cathrine Laustrup; Kjøbsted, Rasmus; Enriori, Pablo J

    2016-01-01

    The melanocortin system includes five G-protein coupled receptors (family A) defined as MC1R-MC5R, which are stimulated by endogenous agonists derived from proopiomelanocortin (POMC). The melanocortin system has been intensely studied for its central actions in body weight and energy expenditure...... pathway involved in α-MSH-stimulated glucose uptake in differentiated L6 myotubes and mouse muscle explants. In order to examine the involvement of AMPK, we investigate -MSH stimulation in both wild type and AMPK deficient mice. We found that -MSH significantly induces phosphorylation of TBC1 domain (TBC1...

  11. Ketamine inhibits tumor necrosis factor-α and interleukin-6 gene expressions in lipopolysaccharide-stimulated macrophages through suppression of toll-like receptor 4-mediated c-Jun N-terminal kinase phosphorylation and activator protein-1 activation

    International Nuclear Information System (INIS)

    Wu, G.-J.; Chen, T.-L.; Ueng, Y.-F.; Chen, R.-M.

    2008-01-01

    Our previous study showed that ketamine, an intravenous anesthetic agent, has anti-inflammatory effects. In this study, we further evaluated the effects of ketamine on the regulation of tumor necrosis factor-α (TNF-α) and interlukin-6 (IL-6) gene expressions and its possible signal-transducing mechanisms in lipopolysaccharide (LPS)-activated macrophages. Exposure of macrophages to 1, 10, and 100 μM ketamine, 100 ng/ml LPS, or a combination of ketamine and LPS for 1, 6, and 24 h was not cytotoxic to macrophages. A concentration of 1000 μM of ketamine alone or in combined treatment with LPS caused significant cell death. Administration of LPS increased cellular TNF-α and IL-6 protein levels in concentration- and time-dependent manners. Meanwhile, treatment with ketamine concentration- and time-dependently alleviated the enhanced effects. LPS induced TNF-α and IL-6 mRNA syntheses. Administration of ketamine at a therapeutic concentration (100 μM) significantly inhibited LPS-induced TNF-α and IL-6 mRNA expressions. Application of toll-like receptor 4 (TLR4) small interfering (si)RNA into macrophages decreased cellular TLR4 levels. Co-treatment of macrophages with ketamine and TLR4 siRNA decreased the LPS-induced TNF-α and IL-6 productions more than alone administration of TLR4 siRNA. LPS stimulated phosphorylation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos from the cytoplasm to nuclei. However, administration of ketamine significantly decreased LPS-induced activation of c-Jun N-terminal kinase and translocation of c-Jun and c-Fos. LPS increased the binding of nuclear extracts to activator protein-1 consensus DNA oligonucleotides. Administration of ketamine significantly ameliorated LPS-induced DNA binding activity of activator protein-1. Therefore, a clinically relevant concentration of ketamine can inhibit TNF-α and IL-6 gene expressions in LPS-activated macrophages. The suppressive mechanisms occur through suppression of TLR4-mediated

  12. Granulocyte-macrophage colony-stimulating factor primes interleukin-13 production by macrophages via protease-activated receptor-2.

    Science.gov (United States)

    Aoki, Manabu; Yamaguchi, Rui; Yamamoto, Takatoshi; Ishimaru, Yasuji; Ono, Tomomichi; Sakamoto, Arisa; Narahara, Shinji; Sugiuchi, Hiroyuki; Hirose, Eiji; Yamaguchi, Yasuo

    2015-04-01

    Chronic inflammation is often linked to the presence of type 2-polarized macrophages, which are induced by the T helper type 2 cytokines interleukin-4 and interleukin-13 (IL-13). IL-13 is a key mediator of tissue fibrosis caused by T helper type 2-based inflammation. Human neutrophil elastase (HNE) plays a pivotal role in the pathogenesis of pulmonary fibrosis. This study investigated the priming effect of granulocyte-macrophage colony-stimulating factor (GM-CSF) on IL-13 expression by macrophages stimulated with HNE. Adherent macrophages were obtained from primary cultures of human mononuclear cells. Expression of IL-13 mRNA and protein by GM-CSF-dependent macrophages was investigated after stimulation with HNE, using the polymerase chain reaction and enzyme-linked immunosorbent assay. GM-CSF had a priming effect on IL-13 mRNA and protein expression by macrophages stimulated with HNE, while this effect was not observed for various other cytokines. GM-CSF-dependent macrophages showed a significant increase in the expression of protease activated receptor-2 (PAR-2) mRNA and protein. The response of IL-13 mRNA to HNE was significantly decreased by pretreatment with alpha1-antitrypsin, a PAR-2 antibody (SAM11), or a PAR-2 antagonist (ENMD-1068). These findings suggest that stimulation with HNE can induce IL-13 production by macrophages, especially GM-CSF-dependent macrophages. Accordingly, neutrophil elastase may have a key role in fibrosis associated with chronic inflammation. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Conserved salt-bridge competition triggered by phosphorylation regulates the protein interactome

    KAUST Repository

    Skinner, John J.

    2017-12-05

    Phosphorylation is a major regulator of protein interactions; however, the mechanisms by which regulation occurs are not well understood. Here we identify a salt-bridge competition or “theft” mechanism that enables a phospho-triggered swap of protein partners by Raf Kinase Inhibitory Protein (RKIP). RKIP transitions from inhibiting Raf-1 to inhibiting G-protein–coupled receptor kinase 2 upon phosphorylation, thereby bridging MAP kinase and G-Protein–Coupled Receptor signaling. NMR and crystallography indicate that a phosphoserine, but not a phosphomimetic, competes for a lysine from a preexisting salt bridge, initiating a partial unfolding event and promoting new protein interactions. Structural elements underlying the theft occurred early in evolution and are found in 10% of homo-oligomers and 30% of hetero-oligomers including Bax, Troponin C, and Early Endosome Antigen 1. In contrast to a direct recognition of phosphorylated residues by binding partners, the salt-bridge theft mechanism represents a facile strategy for promoting or disrupting protein interactions using solvent-accessible residues, and it can provide additional specificity at protein interfaces through local unfolding or conformational change.

  14. Conserved salt-bridge competition triggered by phosphorylation regulates the protein interactome

    KAUST Repository

    Skinner, John J.; Wang, Sheng; Lee, Jiyoung; Ong, Colin; Sommese, Ruth; Sivaramakrishnan, Sivaraj; Koelmel, Wolfgang; Hirschbeck, Maria; Schindelin, Hermann; Kisker, Caroline; Lorenz, Kristina; Sosnick, Tobin R.; Rosner, Marsha Rich

    2017-01-01

    Phosphorylation is a major regulator of protein interactions; however, the mechanisms by which regulation occurs are not well understood. Here we identify a salt-bridge competition or “theft” mechanism that enables a phospho-triggered swap of protein partners by Raf Kinase Inhibitory Protein (RKIP). RKIP transitions from inhibiting Raf-1 to inhibiting G-protein–coupled receptor kinase 2 upon phosphorylation, thereby bridging MAP kinase and G-Protein–Coupled Receptor signaling. NMR and crystallography indicate that a phosphoserine, but not a phosphomimetic, competes for a lysine from a preexisting salt bridge, initiating a partial unfolding event and promoting new protein interactions. Structural elements underlying the theft occurred early in evolution and are found in 10% of homo-oligomers and 30% of hetero-oligomers including Bax, Troponin C, and Early Endosome Antigen 1. In contrast to a direct recognition of phosphorylated residues by binding partners, the salt-bridge theft mechanism represents a facile strategy for promoting or disrupting protein interactions using solvent-accessible residues, and it can provide additional specificity at protein interfaces through local unfolding or conformational change.

  15. Sigma-1 receptor enhances neurite elongation of cerebellar granule neurons via TrkB signaling.

    Science.gov (United States)

    Kimura, Yuriko; Fujita, Yuki; Shibata, Kumi; Mori, Megumi; Yamashita, Toshihide

    2013-01-01

    Sigma-1 receptor (Sig-1R) is an integral membrane protein predominantly expressed in the endoplasmic reticulum. Sig-1R demonstrates a high affinity to various synthetic compounds including well-known psychotherapeutic drugs in the central nervous system (CNS). For that, it is considered as an alternative target for psychotherapeutic drugs. On the cellular level, when Sig-1R is activated, it is known to play a role in neuroprotection and neurite elongation. These effects are suggested to be mediated by its ligand-operated molecular chaperone activity, and/or upregulation of various Ca(2+) signaling. In addition, recent studies show that Sig-1R activation induces neurite outgrowth via neurotrophin signaling. Here, we tested the hypothesis that Sig-1R activation promotes neurite elongation through activation of tropomyosin receptor kinase (Trk), a family of neurotrophin receptors. We found that 2-(4-morpholinethyl)1-phenylcyclohexanecarboxylate (PRE-084), a selective Sig-1R agonist, significantly promoted neurite outgrowth, and K252a, a Trk inhibitor, attenuated Sig-1R-mediated neurite elongation in cerebellar granule neurons (CGNs). Moreover, we revealed that Sig-1R interacts with TrkB, and PRE-084 treatment enhances phosphorylation of Y515, but not Y706. Thus, our results indicate that Sig-1R activation promotes neurite outgrowth in CGNs through Y515 phosphorylation of TrkB.

  16. Angiotensin II reduces cardiac AdipoR1 expression through AT1 receptor/ROS/ERK1/2/c-Myc pathway.

    Directory of Open Access Journals (Sweden)

    Li Li

    Full Text Available Adiponectin, an abundant adipose tissue-derived protein, exerts protective effect against cardiovascular disease. Adiponectin receptors (AdipoR1 and AdipoR2 mediate the beneficial effects of adiponectin on the cardiovascular system. However, the alteration of AdipoRs in cardiac remodeling is not fully elucidated. Here, we investigated the effect of angiotensin II (AngII on cardiac AdipoRs expression and explored the possible molecular mechanism. AngII infusion into rats induced cardiac hypertrophy, reduced AdipoR1 but not AdipoR2 expression, and attenuated the phosphorylations of adenosine monophosphate-activated protein kinase and acetyl coenzyme A carboxylase, and those effects were all reversed by losartan, an AngII type 1 (AT1 receptor blocker. AngII reduced expression of AdipoR1 mRNA and protein in cultured neonatal rat cardiomyocytes, which was abolished by losartan, but not by PD123319, an AT2 receptor antagonist. The antioxidants including reactive oxygen species (ROS scavenger NAC, NADPH oxidase inhibitor apocynin, Nox2 inhibitor peptide gp91 ds-tat, and mitochondrial electron transport chain complex I inhibitor rotenone attenuated AngII-induced production of ROS and phosphorylation of extracellular signal-regulated kinase (ERK 1/2. AngII-reduced AdipoR1 expression was reversed by pretreatment with NAC, apocynin, gp91 ds-tat, rotenone, and an ERK1/2 inhibitor PD98059. Chromatin immunoprecipitation assay demonstrated that AngII provoked the recruitment of c-Myc onto the promoter region of AdipoR1, which was attenuated by PD98059. Moreover, AngII-induced DNA binding activity of c-Myc was inhibited by losartan, NAC, apocynin, gp91 ds-tat, rotenone, and PD98059. c-Myc small interfering RNA abolished the inhibitory effect of AngII on AdipoR1 expression. Our results suggest that AngII inhibits cardiac AdipoR1 expression in vivo and in vitro and AT1 receptor/ROS/ERK1/2/c-Myc pathway is required for the downregulation of AdipoR1 induced by AngII.

  17. Immunohistochemical expression of interleukin-2 receptor and interleukin-6 in patients with prostate cancer and benign prostatic hyperplasia: association with asymptomatic inflammatory prostatitis NIH category IV.

    Science.gov (United States)

    Engelhardt, Paul Friedrich; Seklehner, Stephan; Brustmann, Hermann; Lusuardi, Lukas; Riedl, Claus R

    2015-04-01

    This study prospectively investigated the immunohistochemical expression of interleukin-2 receptor (IL-2R) and interleukin-6 (IL-6) in patients with prostate cancer and benign prostatic hyperplasia (BPH), and a possible association of these conditions with asymptomatic inflammatory prostatitis National Institutes of Health (NIH) category IV. The study included 139 consecutive patients who underwent transurethral resection of the prostate and transvesical enucleation of the prostate (n = 82) or radical prostatectomy (n = 57). To characterize inflammatory changes the criteria proposed by Irani et al. [J Urol 1997;157:1301-3] were used. IL-2R and IL-6 expression was studied by a standard immunohistochemical method. Results were correlated with tumour, node, metastasis stage, Gleason scores, total prostate-specific antigen, International Prostate Symptom Score and body mass index. IL-2R and IL-6 expression was significantly higher in neoplastic prostate cancer tissue than in normal tissue of prostate cancer patients (p Prostate cancer patients with prostatitis showed significantly higher IL-2R expression than those without inflammation (p prostatitis than in those without (p prostate cancer tissue than in normal tissue. Patients with asymptomatic inflammatory prostatitis NIH category IV showed significantly greater activity.

  18. Cytokines and Bone Loss in a 5-Year Longitudinal Study—Hormone Replacement Therapy Suppresses Serum Soluble Interleukin-6 Receptor and Increases Interleukin-1-Receptor Antagonist

    DEFF Research Database (Denmark)

    Abrahamsen, B.; Bonnevie-Nielsen, V.; Ebbesen, E.N.

    2000-01-01

    ) and the soluble IL-6 receptor (sIL-6R) potentially modify cytokine bioactivity. We therefore assessed the impact of menopause and hormone replacement therapy (HRT) on cytokines and activity modifiers in serum within a 5-year longitudinal study. One hundred sixty perimenopausal women (age 50.1 +/- 2.8 years) were.......16; p = 0.17). In conclusion, serum IL-1ra and sIL-6R are influenced by HRT and are associated with the rate of bone loss in perimenopausal women....

  19. Phosphorylated c-Mpl tyrosine 591 regulates thrombopoietin-induced signaling.

    Science.gov (United States)

    Sangkhae, Veena; Saur, Sebastian Jonas; Kaushansky, Alexis; Kaushansky, Kenneth; Hitchcock, Ian Stuart

    2014-06-01

    Thrombopoietin (TPO) is the primary regulator of platelet production, affecting cell survival, proliferation, and differentiation through binding to and stimulation of the cell surface receptor the cellular myeloproliferative leukemia virus oncogene (c-Mpl). Activating mutations in c-Mpl constitutively stimulate downstream signaling pathways, leading to aberrant hematopoiesis, and contribute to development of myeloproliferative neoplasms. Several studies have mapped the tyrosine residues within the cytoplasmic domain of c-Mpl that mediate these cellular signals; however, secondary signaling pathways are incompletely understood. In this study, we focused on c-Mpl tyrosine 591 (Y591). We found Y591 of wild-type c-Mpl to be phosphorylated in the presence of TPO. Additionally, eliminating Y591 phosphorylation by mutation to Phe resulted in decreased total receptor phosphorylation. Using a Src homology 2/phosphotyrosine-binding (SH2/PTB) domain binding microarray, we identified novel c-Mpl binding partners for phosphorylated Y591, including Src homology region 2 domain-containing phosphatase-1 (SHP-1), spleen tyrosine kinase (SYK) and Bruton's tyrosine kinase (BTK). The functional significance of binding partners was determined through small interfering RNA treatment of Ba/F3-Mpl cells, confirming that the increase in pERK1/2 resulting from removal of Y591 may be mediated by spleen tyrosine kinase. These findings identify a novel negative regulatory pathway that controls TPO-mediated signaling, advancing our understanding of the mechanisms required for successful maintenance of hematopoietic stem cells and megakaryocyte development. Copyright © 2014 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.

  20. Ligand binding affinity at the insulin receptor isoform A (IR-A and subsequent IR-A tyrosine phosphorylation kinetics are important determinants of mitogenic biological outcomes.

    Directory of Open Access Journals (Sweden)

    Harinda eRajapaksha

    2015-07-01

    Full Text Available The insulin receptor (IR is a tyrosine kinase receptor that can mediate both metabolic and mitogenic biological actions. The IR isoform-A (IR-A arises from alternative splicing of exon 11 and has different ligand binding and signalling properties compared to the IR isoform-B. The IR-A not only binds insulin but also insulin-like growth factor-II (IGF-II with high affinity. IGF-II acting through the IR-A promotes cancer cell proliferation, survival and migration by activating some unique signalling molecules compared to those activated by insulin. This observation led us to investigate whether the different IR-A signalling outcomes in response to IGF-II and insulin could be attributed to phosphorylation of a different subset of IR-A tyrosine residues or to the phosphorylation kinetics. We correlated IR-A phosphorylation to activation of molecules involved in mitogenic and metabolic signalling (MAPK and Akt and receptor internalisation rates (related to mitogenic signalling. We also extended this study to incorporate two ligands that are known to promote predominantly mitogenic ([His4, Tyr15, Thr49, Ile51] IGF-I, qIGF-I or metabolic (S597 peptide biological actions, to see if common mechanisms can be used to define mitogenic or metabolic signalling through the IR-A. The 3-fold lower mitogenic action of IGF-II compared to insulin was associated with a decreased potency in activation of Y960, Y1146, Y1150, Y1151, Y1316 and Y1322, in MAPK phosphorylation and in IR-A internalization. With the poorly mitogenic S597 peptide it was a decreased rate of tyrosine phosphorylation rather than potency that was associated with a low mitogenic potential. We conclude that both decreased affinity of IR-A binding and the kinetics of IR-A phosphorylation can independently lead to a lower mitogenic activity. None of the studied parameters could account for the lower metabolic activity of qIGF-I.

  1. The anti-interleukin-1 in type 1 diabetes action trial--background and rationale

    DEFF Research Database (Denmark)

    Pickersgill, Linda M S; Mandrup-Poulsen, Thomas R

    2009-01-01

    Type 1 diabetes (T1D) is caused by an inflammatory destruction of pancreatic beta-cells. Pro-inflammatory cytokines, in particular interleukin-1 (IL-1), have been suggested to be effector molecules based on the observations that pro-inflammatory cytokines cause beta-cell apoptosis in vitro...... and aggravate diabetes in vivo, and that inhibition of the action of these cytokines reduce diabetes incidence in animal models of type 1 diabetes and islet graft destruction. This review presents the rationale for and design of a recently launched double-blind, multicenter, randomized clinical trial...... that investigates the effect of interleukin-1 antagonism on beta-cell function in subjects with T1D of recent-onset....

  2. Helicobacter pylori VacA, acting through receptor protein tyrosine phosphatase ?, is crucial for CagA phosphorylation in human duodenum carcinoma cell line AZ-521

    OpenAIRE

    Nakano, Masayuki; Yahiro, Kinnosuke; Yamasaki, Eiki; Kurazono, Hisao; Akada, Junko; Yamaoka, Yoshio; Niidome, Takuro; Hatakeyama, Masanori; Suzuki, Hidekazu; Yamamoto, Taro; Moss, Joel; Isomoto, Hajime; Hirayama, Toshiya

    2016-01-01

    ABSTRACT Helicobacter pylori, a major cause of gastroduodenal diseases, produces vacuolating cytotoxin (VacA) and cytotoxin-associated gene A (CagA), which seem to be involved in virulence. VacA exhibits pleiotropic actions in gastroduodenal disorders via its specific receptors. Recently, we found that VacA induced the phosphorylation of cellular Src kinase (Src) at Tyr418 in AZ-521 cells. Silencing of receptor protein tyrosine phosphatase (RPTP)?, a VacA receptor, reduced VacA-induced Src ph...

  3. The IkappaB kinase family phosphorylates the Parkinson's disease kinase LRRK2 at Ser935 and Ser910 during Toll-like receptor signaling.

    Directory of Open Access Journals (Sweden)

    Nicolas Dzamko

    Full Text Available Mutations in leucine-rich repeat kinase 2 (LRRK2 are strongly associated with late-onset autosomal dominant Parkinson's disease. LRRK2 is highly expressed in immune cells and recent work points towards a link between LRRK2 and innate immunity. Here we demonstrate that stimulation of the Toll-Like Receptor (TLR pathway by MyD88-dependent agonists in bone marrow-derived macrophages (BMDMs or RAW264.7 macrophages induces marked phosphorylation of LRRK2 at Ser910 and Ser935, the phosphorylation sites that regulate the binding of 14-3-3 to LRRK2. Phosphorylation of these residues is prevented by knock-out of MyD88 in BMDMs, but not the alternative TLR adaptor protein TRIF. Utilising both pharmacological inhibitors, including a new TAK1 inhibitor, NG25, and genetic models, we provide evidence that both the canonical (IKKα and IKKβ and IKK-related (IKKε and TBK1 kinases mediate TLR agonist induced phosphorylation of LRRK2 in vivo. Moreover, all four IKK members directly phosphorylate LRRK2 at Ser910 and Ser935 in vitro. Consistent with previous work describing Ser910 and Ser935 as pharmacodynamic biomarkers of LRRK2 activity, we find that the TLR independent basal phosphorylation of LRRK2 at Ser910 and Ser935 is abolished following treatment of macrophages with LRRK2 kinase inhibitors. However, the increased phosphorylation of Ser910 and Ser935 induced by activation of the MyD88 pathway is insensitive to LRRK2 kinase inhibitors. Finally, employing LRRK2-deficient BMDMs, we present data indicating that LRRK2 does not play a major role in regulating the secretion of inflammatory cytokines induced by activation of the MyD88 pathway. Our findings provide the first direct link between LRRK2 and the IKKs that mediate many immune responses. Further work is required to uncover the physiological roles that phosphorylation of LRRK2 by IKKs play in controlling macrophage biology and to determine how phosphorylation of LRRK2 by IKKs impacts upon the use of Ser

  4. Phosphorylation regulates human T-cell leukemia virus type 1 Rex function

    Directory of Open Access Journals (Sweden)

    Ward Michael

    2009-11-01

    Full Text Available Abstract Background Human T-cell leukemia virus type 1 (HTLV-1 is a pathogenic complex deltaretrovirus, which is the causative agent of adult T-cell leukemia/lymphoma (ATL and HTLV-1-associated myelopathy/tropical spastic paraparesis. In addition to the structural and enzymatic viral gene products, HTLV-1 encodes the positive regulatory proteins Tax and Rex along with viral accessory proteins. Tax and Rex proteins orchestrate the timely expression of viral genes important in viral replication and cellular transformation. Rex is a nucleolar-localizing shuttling protein that acts post-transcriptionally by binding and facilitating the export of the unspliced and incompletely spliced viral mRNAs from the nucleus to the cytoplasm. HTLV-1 Rex (Rex-1 is a phosphoprotein and general protein kinase inhibition correlates with reduced function. Therefore, it has been proposed that Rex-1 function may be regulated through site-specific phosphorylation. Results We conducted a phosphoryl mapping of Rex-1 over-expressed in transfected 293 T cells using a combination of affinity purification and liquid chromatography tandem mass spectrometry. We achieved 100% physical coverage of the Rex-1 polypeptide and identified five novel phosphorylation sites at Thr-22, Ser-36, Thr-37, Ser-97, and Ser-106. We also confirmed evidence of two previously identified residues, Ser-70 and Thr-174, but found no evidence of phosphorylation at Ser-177. The functional significance of these phosphorylation events was evaluated using a Rex reporter assay and site-directed mutational analysis. Our results indicate that phosphorylation at Ser-97 and Thr-174 is critical for Rex-1 function. Conclusion We have mapped completely the site-specific phosphorylation of Rex-1 identifying a total of seven residues; Thr-22, Ser-36, Thr-37, Ser-70, Ser-97, Ser-106, and Thr-174. Overall, this work is the first to completely map the phosphorylation sites in Rex-1 and provides important insight into

  5. Synergistic augmentation of ATP-induced interleukin-6 production by arsenite in HaCaT cells.

    Science.gov (United States)

    Sumi, Daigo; Asao, Masashi; Okada, Hideta; Yogi, Kuniko; Miyataka, Hideki; Himeno, Seiichiro

    2016-06-01

    Chronic arsenic exposure causes cutaneous diseases such as hyperkeratosis and skin cancer. However, little information has been available regarding the molecular mechanisms underlying these symptoms. Because extracellular ATP and interleukin-6 (IL-6) are involved in pathological aspects of cutaneous diseases, we examined whether sodium arsenite (As(III)) affects ATP-induced IL-6 production in human epidermal keratinocyte HaCaT cells. The results showed that the addition of As(III) into the medium of HaCaT cells dose dependently increased the production of IL-6 induced by extracellular ATP, although As(III) alone had no effect on IL-6 production. To elucidate the mechanism of the synergistic effect of As(III) on IL-6 production by extracellular ATP, we next examined the phosphorylation of p38, ERK and epidermal growth factor receptor (EGFR), since we found that these signaling molecules were stimulated by exposure to extracellular ATP. The results indicated that ATP-induced phosphorylation of p38, ERK and EGFR was synergistically enhanced by co-exposure to As(III). To clarify the mechanisms underlying the enhanced phosphorylation of p38, ERK and EGFR by As(III), we explored two possible mechanisms: the inhibition of extracellular ATP degradation and the inhibition of protein tyrosine phosphatases (PTPs) activity by As(III). The degradation of extracellular ATP was not changed by As(III), whereas the activity of PTPs was significantly inhibited by As(III). Our results suggest that As(III) augments ATP-induced IL-6 production in HaCaT cells through enhanced phosphorylation of the EGFR and p38/ERK pathways, which is associated with the inhibition of PTPs activity.

  6. The role of interleukin-8 (IL-8) and IL-8 receptors in platinum response in high grade serous ovarian carcinoma.

    Science.gov (United States)

    Stronach, Euan A; Cunnea, Paula; Turner, Christina; Guney, Tankut; Aiyappa, Radhika; Jeyapalan, Senthuran; de Sousa, Camila H; Browne, Alacoque; Magdy, Nesreen; Studd, James B; Sriraksa, Ruethairat; Gabra, Hani; El-Bahrawy, Mona

    2015-10-13

    Platinum based drugs are the cornerstone of chemotherapy for ovarian cancer, however the development of chemoresistance hinders its success. IL-8 is involved in regulating several pro-survival pathways in cancer. We studied the expression of IL-8 and IL-8 receptors in platinum sensitive and resistant cell lines. Using qRT-PCR and immunohistochemistry, both platinum sensitive (PEA1, PEO14) and resistant (PEA2, PEO23) show increased expression of IL-8 and IL-8 receptors. IL-8RA shows nuclear and cytoplasmic expression, whilst IL-8RB is present solely in the cytoplasm. Knockdown of IL-8 increased sensitivity to cisplatin in platinum sensitive and reversed platinum resistance in resistant cell lines, decreased the expression of anti-apoptotic Bcl-2 and decreased inhibitory phosphorylation of pro-apoptotic Bad. IL-8 receptor antagonist treatment also enhanced platinum sensitivity. Nuclear localisation of IL-8RA was only detected in platinum resistant tumours. Inhibition of IL-8 signalling can enhance response in platinum sensitive and resistant disease. Nuclear IL-8RA may have potential as a biomarker of resistant disease.

  7. Lack of Association between an Interleukin-I Receptor Antagonist Gene Polymorphism and Systemic Lupus Erythematosus

    Directory of Open Access Journals (Sweden)

    Victor A. Danis

    1994-01-01

    Full Text Available Non-MHC linked genes may contribute to genetic predisposition to the development of systemic lupus erythematosus. The possibility that cytokine genes may be involved was raised by the observation of increased frequency in expression of an uncommon allele of an interleukin-I receptor antagonist gene polymorphism and SLE in a recent U.K. study. We have not been able to show any significant differences in expression of this allele in SLE patients as a whole or in any patient subgroups. Our results actually show a slight decrease in the expression of this allele in SLE patients compared with healthy controls and in SLE patients with malar rash compared with SLE patients without malar rash.

  8. Inhibition of Toll-like receptor 2-mediated interleukin-8 production in Cystic Fibrosis airway epithelial cells via the alpha7-nicotinic acetylcholine receptor.

    LENUS (Irish Health Repository)

    Greene, Catherine M

    2010-01-01

    Cystic Fibrosis (CF) is an inherited disorder characterised by chronic inflammation of the airways. The lung manifestations of CF include colonization with Pseudomonas aeruginosa and Staphylococcus aureus leading to neutrophil-dominated airway inflammation and tissue damage. Inflammation in the CF lung is initiated by microbial components which activate the innate immune response via Toll-like receptors (TLRs), increasing airway epithelial cell production of proinflammatory mediators such as the neutrophil chemokine interleukin-8 (IL-8). Thus modulation of TLR function represents a therapeutic approach for CF. Nicotine is a naturally occurring plant alkaloid. Although it is negatively associated with cigarette smoking and cardiovascular damage, nicotine also has anti-inflammatory properties. Here we investigate the inhibitory capacity of nicotine against TLR2- and TLR4-induced IL-8 production by CFTE29o- airway epithelial cells, determine the role of alpha7-nAChR (nicotinic acetylcholine receptor) in these events, and provide data to support the potential use of safe nicotine analogues as anti-inflammatories for CF.

  9. Opposing regulation of PROX1 by interleukin-3 receptor and NOTCH directs differential host cell fate reprogramming by Kaposi sarcoma herpes virus.

    Directory of Open Access Journals (Sweden)

    Jaehyuk Yoo

    Full Text Available Lymphatic endothelial cells (LECs are differentiated from blood vascular endothelial cells (BECs during embryogenesis and this physiological cell fate specification is controlled by PROX1, the master regulator for lymphatic development. When Kaposi sarcoma herpes virus (KSHV infects host cells, it activates the otherwise silenced embryonic endothelial differentiation program and reprograms their cell fates. Interestingly, previous studies demonstrated that KSHV drives BECs to acquire a partial lymphatic phenotype by upregulating PROX1 (forward reprogramming, but stimulates LECs to regain some BEC-signature genes by downregulating PROX1 (reverse reprogramming. Despite the significance of this KSHV-induced bidirectional cell fate reprogramming in KS pathogenesis, its underlying molecular mechanism remains undefined. Here, we report that IL3 receptor alpha (IL3Rα and NOTCH play integral roles in the host cell type-specific regulation of PROX1 by KSHV. In BECs, KSHV upregulates IL3Rα and phosphorylates STAT5, which binds and activates the PROX1 promoter. In LECs, however, PROX1 was rather downregulated by KSHV-induced NOTCH signal via HEY1, which binds and represses the PROX1 promoter. Moreover, PROX1 was found to be required to maintain HEY1 expression in LECs, establishing a reciprocal regulation between PROX1 and HEY1. Upon co-activation of IL3Rα and NOTCH, PROX1 was upregulated in BECs, but downregulated in LECs. Together, our study provides the molecular mechanism underlying the cell type-specific endothelial fate reprogramming by KSHV.

  10. Quantitative Phospho-proteomic Analysis of TNFα/NFκB Signaling Reveals a Role for RIPK1 Phosphorylation in Suppressing Necrotic Cell Death.

    Science.gov (United States)

    Mohideen, Firaz; Paulo, Joao A; Ordureau, Alban; Gygi, Steve P; Harper, J Wade

    2017-07-01

    TNFα is a potent inducer of inflammation due to its ability to promote gene expression, in part via the NFκB pathway. Moreover, in some contexts, TNFα promotes Caspase-dependent apoptosis or RIPK1/RIPK3/MLKL-dependent necrosis. Engagement of the TNF Receptor Signaling Complex (TNF-RSC), which contains multiple kinase activities, promotes phosphorylation of several downstream components, including TAK1, IKKα/IKKβ, IκBα, and NFκB. However, immediate downstream phosphorylation events occurring in response to TNFα signaling are poorly understood at a proteome-wide level. Here we use Tandem Mass Tagging-based proteomics to quantitatively characterize acute TNFα-mediated alterations in the proteome and phosphoproteome with or without inhibition of the cIAP-dependent survival arm of the pathway with a SMAC mimetic. We identify and quantify over 8,000 phosphorylated peptides, among which are numerous known sites in the TNF-RSC, NFκB, and MAP kinase signaling systems, as well as numerous previously unrecognized phosphorylation events. Functional analysis of S320 phosphorylation in RIPK1 demonstrates a role for this event in suppressing its kinase activity, association with CASPASE-8 and FADD proteins, and subsequent necrotic cell death during inflammatory TNFα stimulation. This study provides a resource for further elucidation of TNFα-dependent signaling pathways. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Sleeping Beauty Transposition of Chimeric Antigen Receptors Targeting Receptor Tyrosine Kinase-Like Orphan Receptor-1 (ROR1 into Diverse Memory T-Cell Populations.

    Directory of Open Access Journals (Sweden)

    Drew C Deniger

    Full Text Available T cells modified with chimeric antigen receptors (CARs targeting CD19 demonstrated clinical activity against some B-cell malignancies. However, this is often accompanied by a loss of normal CD19+ B cells and humoral immunity. Receptor tyrosine kinase-like orphan receptor-1 (ROR1 is expressed on sub-populations of B-cell malignancies and solid tumors, but not by healthy B cells or normal post-partum tissues. Thus, adoptive transfer of T cells specific for ROR1 has potential to eliminate tumor cells and spare healthy tissues. To test this hypothesis, we developed CARs targeting ROR1 in order to generate T cells specific for malignant cells. Two Sleeping Beauty transposons were constructed with 2nd generation ROR1-specific CARs signaling through CD3ζ and either CD28 (designated ROR1RCD28 or CD137 (designated ROR1RCD137 and were introduced into T cells. We selected for T cells expressing CAR through co-culture with γ-irradiated activating and propagating cells (AaPC, which co-expressed ROR1 and co-stimulatory molecules. Numeric expansion over one month of co-culture on AaPC in presence of soluble interleukin (IL-2 and IL-21 occurred and resulted in a diverse memory phenotype of CAR+ T cells as measured by non-enzymatic digital array (NanoString and multi-panel flow cytometry. Such T cells produced interferon-γ and had specific cytotoxic activity against ROR1+ tumors. Moreover, such cells could eliminate ROR1+ tumor xenografts, especially T cells expressing ROR1RCD137. Clinical trials will investigate the ability of ROR1-specific CAR+ T cells to specifically eliminate tumor cells while maintaining normal B-cell repertoire.

  12. Generation of a Novel T Cell Specific Interleukin-1 Receptor Type 1 Conditional Knock Out Mouse Reveals Intrinsic Defects in Survival, Expansion and Cytokine Production of CD4 T Cells.

    Directory of Open Access Journals (Sweden)

    Ilgiz A Mufazalov

    Full Text Available Interleukin-1 (IL-1 plays a crucial role in numerous inflammatory diseases via action on its only known signaling IL-1 receptor type 1 (IL-1R1. To investigate the role of IL-1 signaling in selected cell types, we generated a new mouse strain in which exon 5 of the Il1r1 gene is flanked by loxP sites. Crossing of these mice with CD4-Cre transgenic mice resulted in IL-1R1 loss of function specifically in T cells. These mice, termed IL-1R1ΔT, displayed normal development under steady state conditions. Importantly, isolated CD4 positive T cells retained their capacity to differentiate toward Th1 or Th17 cell lineages in vitro, and strongly proliferated in cultures supplemented with either anti-CD3/CD28 or Concanavalin A, but, as predicted, were completely unresponsive to IL-1β administration. Furthermore, IL-1R1ΔT mice were protected from gut inflammation in the anti-CD3 treatment model, due to dramatically reduced frequencies and absolute numbers of IL-17A and interferon (IFN-γ producing cells. Taken together, our data shows the necessity of intact IL-1 signaling for survival and expansion of CD4 T cells that were developed in an otherwise IL-1 sufficient environment.

  13. Medicinal Chemistry, Pharmacology, and Clinical Implications of TRPV1 Receptor Antagonists.

    Science.gov (United States)

    Aghazadeh Tabrizi, Mojgan; Baraldi, Pier Giovanni; Baraldi, Stefania; Gessi, Stefania; Merighi, Stefania; Borea, Pier Andrea

    2017-07-01

    Transient receptor potential vanilloid 1 (TRPV1) is an ion channel expressed on sensory neurons triggering an influx of cations. TRPV1 receptors function as homotetramers responsive to heat, proinflammatory substances, lipoxygenase products, resiniferatoxin, endocannabinoids, protons, and peptide toxins. Its phosphorylation increases sensitivity to both chemical and thermal stimuli, while desensitization involves a calcium-dependent mechanism resulting in receptor dephosphorylation. TRPV1 functions as a sensor of noxious stimuli and may represent a target to avoid pain and injury. TRPV1 activation has been associated to chronic inflammatory pain and peripheral neuropathy. Its expression is also detected in nonneuronal areas such as bladder, lungs, and cochlea where TRPV1 activation is responsible for pathology development of cystitis, asthma, and hearing loss. This review offers a comprehensive overview about TRPV1 receptor in the pathophysiology of chronic pain, epilepsy, cough, bladder disorders, diabetes, obesity, and hearing loss, highlighting how drug development targeting this channel could have a clinical therapeutic potential. Furthermore, it summarizes the advances of medicinal chemistry research leading to the identification of highly selective TRPV1 antagonists and their analysis of structure-activity relationships (SARs) focusing on new strategies to target this channel. © 2016 Wiley Periodicals, Inc.

  14. The phosphorylation state of CD3gamma influences T cell responsiveness and controls T cell receptor cycling

    DEFF Research Database (Denmark)

    Dietrich, J; Bäckström, T; Lauritsen, J P

    1998-01-01

    The T cell receptor (TCR) is internalized following activation of protein kinase C (PKC) via a leucine (Leu)-based motif in CD3gamma. Some studies have indicated that the TCR is recycled back to the cell surface following PKC-mediated internalization. The functional state of recycled TCR and the ......The T cell receptor (TCR) is internalized following activation of protein kinase C (PKC) via a leucine (Leu)-based motif in CD3gamma. Some studies have indicated that the TCR is recycled back to the cell surface following PKC-mediated internalization. The functional state of recycled TCR...... the phosphorylation state of CD3gamma and T cell responsiveness. Based on these observations a physiological role of CD3gamma and TCR cycling is proposed....

  15. Crystal Structure of Human Interferon-[lamda]1 in Complex with Its High-Affinity Receptor Interferon-[lamda]R1

    Energy Technology Data Exchange (ETDEWEB)

    Miknis, Zachary; Magracheva, Eugenia; Li, Wei; Zdanov, Alexander; Kotenko, Sergei V.; Wlodawer, Alexander (NJMS); (NCI)

    2010-12-01

    Interferon (IFN)-{lambda}1 [also known as interleukin (IL)-29] belongs to the recently discovered group of type III IFNs. All type III IFNs initiate signaling processes through formation of specific heterodimeric receptor complexes consisting of IFN-{lambda}R1 and IL-10R2. We have determined the structure of human IFN-{lambda}1 complexed with human IFN-{lambda}R1, a receptor unique to type III IFNs. The overall structure of IFN-{lambda}1 is topologically similar to the structure of IL-10 and other members of the IL-10 family of cytokines. IFN-{lambda}R1 consists of two distinct domains having fibronectin type III topology. The ligand-receptor interface includes helix A, loop AB, and helix F on the IFN site, as well as loops primarily from the N-terminal domain and inter-domain hinge region of IFN-{lambda}R1. Composition and architecture of the interface that includes only a few direct hydrogen bonds support an idea that long-range ionic interactions between ligand and receptor govern the process of initial recognition of the molecules while hydrophobic interactions finalize it.

  16. Distinct signalling properties of insulin receptor substrate (IRS)-1 and IRS-2 in mediating insulin/IGF-1 action

    DEFF Research Database (Denmark)

    Rabiee, Atefeh; Krüger, Marcus; Ardenkjær-Larsen, Jacob

    2018-01-01

    Insulin/IGF-1 action is driven by a complex and highly integrated signalling network. Loss-of-function studies indicate that the major insulin/IGF-1 receptor substrate (IRS) proteins, IRS-1 and IRS-2, mediate different biological functions in vitro and in vivo, suggesting specific signalling...... properties despite their high degree of homology. To identify mechanisms contributing to the differential signalling properties of IRS-1 and IRS-2 in the mediation of insulin/IGF-1 action, we performed comprehensive mass spectrometry (MS)-based phosphoproteomic profiling of brown preadipocytes from wild type......, IRS-1-/-and IRS-2-/-mice in the basal and IGF-1-stimulated states. We applied stable isotope labeling by amino acids in cell culture (SILAC) for the accurate quantitation of changes in protein phosphorylation. We found ~10% of the 6262 unique phosphorylation sites detected to be regulated by IGF-1...

  17. Neonatal CD8+ T-cell differentiation is dependent on interleukin-12.

    LENUS (Irish Health Repository)

    McCarron, Mark J

    2012-02-01

    Neonatal CD8(+) T-cell activation is significantly impaired compared with that in adults. Recent studies have demonstrated that interleukin (IL)-12 is necessary as a third signal, in addition to antigen and co-stimulation, to authorize the differentiation of naive CD8(+) T cells. We examined whether human neonatal CD8(+) T cells, which possess an exclusively naive T-cell phenotype, required a third signal to authorize a productive T-cell response. IL-12 enhanced activated naive CD8(+) T-cell survival, expansion, CD25 expression, and IL-2 production. Activated CD8(+) T cells produced interferon-gamma and intracellular granzyme B and were cytotoxic only in the presence of IL-12. Sustained IL-12 signaling for 72 hours was required for optimal interferon-gamma production. IL-12, in concert with T cell receptor (TCR) stimulation, sustained late-stage (48-72 hours) intracellular phosphorylation and particularly total protein levels of the proximal TCR components, Lck, and CD3xi. The requirement for a third signal for productive human neonatal CD8(+) T-cell differentiation may have implications for neonatal vaccination strategies.

  18. Thromboxane A2 increases endothelial permeability through upregulation of interleukin-8

    International Nuclear Information System (INIS)

    Kim, Su-Ryun; Bae, Soo-Kyung; Park, Hyun-Joo; Kim, Mi-Kyoung; Kim, Koanhoi; Park, Shi-Young; Jang, Hye-Ock; Yun, Il; Kim, Yung-Jin; Yoo, Mi-Ae; Bae, Moon-Kyoung

    2010-01-01

    Thromboxane A 2 (TXA 2 ), a major prostanoid formed from prostaglandin H 2 by thromboxane synthase, is involved in the pathogenesis of a variety of vascular diseases. In this study, we report that TXA 2 mimetic U46619 significantly increases the endothelial permeability both in vitro and in vivo. U46619 enhanced the expression and secretion of interleukin-8 (IL-8), a major inducer of vascular permeability, in endothelial cells. Promoter analysis showed that the U46619-induced expression of IL-8 was mainly regulated by nuclear factor-κB (NF-κB). U46619 induced the activation of NF-κB through IκB kinase (IKK) activation, IκB phosphorylation and NF-κB nuclear translocation. Furthermore, the inhibition of IL-8 or blockade of the IL-8 receptor attenuated the U46619-induced endothelial cell permeability by modulating the cell-cell junctions. Overall, these results suggest that U46619 promotes vascular permeability through the production of IL-8 via NF-κB activation in endothelial cells.

  19. Interleukin 1 as an autocrine growth factor for acute myeloid leukemia cells

    International Nuclear Information System (INIS)

    Cozzolino, F.; Rubartelli, A.; Aldinucci, D.; Sitia, R.; Torcia, M.; Shaw, A.; Di Guglielmo, R.

    1989-01-01

    Production of interleukin 1 (IL-1) by leukemic cells was studied in 13 cases of acute myeloid leukemia. Intracytoplasmic immunofluorescence studies showed that the cells invariably contained the cytokine. Endogenous labeling studies demonstrated that acute myeloid leukemia cells produced either only the 33-kDa propeptide or both the propeptide and the 17-kDa mature form of IL-1β. The 33-kDa propeptide IL-1α was always produced but was less frequently released. Involvement of IL-1 in leukemic cell growth was investigated using two antibodies specific for IL-1 subtypes, which inhibited spontaneous cell proliferation in the six cases studied. After acid treatment of the cells, a surface receptor for IL-1 could be demonstrated, which mediated 125 I-labeled IL-1-specific uptake by leukemic cells. Furthermore, recombinant IL-1α or IL-1β induced significant cell proliferation in 10 12 cases. The above findings were uncorrelated with the cytologic type (French-American-British classification) of leukemia. The studies suggest that IL-1 may act as an autocrine growth factor in most cases of acute myeloid leukemia

  20. One week treatment with the IL-1 receptor antagonist anakinra leads to a sustained improvement in insulin sensitivity in insulin resistant patients with type 1 diabetes mellitus

    NARCIS (Netherlands)

    Asseldonk, van E.J.P.; Poppel, van P.C.M.; Ballak, D.B.; Stienstra, Rinke; Netea, M.G.; Tack, C.J.

    2015-01-01

    Inflammation associated with obesity is involved in the development of insulin resistance. We hypothesized that anti-inflammatory treatment with the Interleukin-1 receptor antagonist anakinra would improve insulin sensitivity.In an open label proof-of-concept study, we included overweight

  1. SH2-B promotes insulin receptor substrate 1 (IRS1)- and IRS2-mediated activation of the phosphatidylinositol 3-kinase pathway in response to leptin.

    Science.gov (United States)

    Duan, Chaojun; Li, Minghua; Rui, Liangyou

    2004-10-15

    Leptin regulates energy homeostasis primarily by binding and activating its long form receptor (LRb). Deficiency of either leptin or LRb causes morbid obesity. Leptin stimulates LRb-associated JAK2, thus initiating multiple pathways including the Stat3 and phosphatidylinositol (PI) 3-kinase pathways that mediate leptin biological actions. Here we report that SH2-B, a JAK2-interacting protein, promotes activation of the PI 3-kinase pathway by recruiting insulin receptor substrate 1 (IRS1) and IRS2 in response to leptin. SH2-B directly bound, via its PH and SH2 domain, to both IRS1 and IRS2 both in vitro and in intact cells and mediated formation of a JAK2/SH2-B/IRS1 or IRS2 tertiary complex. Consequently, SH2-B dramatically enhanced leptin-stimulated tyrosine phosphorylation of IRS1 and IRS2 in HEK293 cells stably expressing LRb, thus promoting association of IRS1 and IRS2 with the p85 regulatory subunit of PI 3-kinase and phosphorylation and activation of Akt. SH2-B mutants with lower affinity for IRS1 and IRS2 exhibited reduced ability to promote association of JAK2 with IRS1, tyrosine phosphorylation of IRS1, and association of IRS1 with p85 in response to leptin. Moreover, deletion of the SH2-B gene impaired leptin-stimulated tyrosine phosphorylation of endogenous IRS1 in mouse embryonic fibroblasts (MEF), which was reversed by reintroduction of SH2-B. Similarly, SH2-B promoted growth hormone-stimulated tyrosine phosphorylation of IRS1 in both HEK293 and MEF cells. Our data suggest that SH2-B is a novel mediator of the PI 3-kinase pathway in response to leptin or other hormones and cytokines that activate JAK2.

  2. Activation of the LRR Receptor-Like Kinase PSY1R Requires Transphosphorylation of Residues in the Activation Loop

    Directory of Open Access Journals (Sweden)

    Christian B. Oehlenschlæger

    2017-11-01

    Full Text Available PSY1R is a leucine-rich repeat (LRR receptor-like kinase (RLK previously shown to act as receptor for the plant peptide hormone PSY1 (peptide containing sulfated tyrosine 1 and to regulate cell expansion. PSY1R phosphorylates and thereby regulates the activity of plasma membrane-localized H+-ATPases. While this mechanism has been studied in detail, little is known about how PSY1R itself is activated. Here we studied the activation mechanism of PSY1R. We show that full-length PSY1R interacts with members of the SERK co-receptor family in planta. We identified seven in vitro autophosphorylation sites on serine and threonine residues within the kinase domain of PSY1R using mass spectrometry. We furthermore show that PSY1R autophosphorylation occurs in trans and that the initial transphosphorylation takes place within the activation loop at residues Ser951, Thr959, and Thr963. While Thr959 and Thr963 are conserved among other related plant LRR RLKs, Ser951 is unique to PSY1R. Based on homology modeling we propose that phosphorylation of Ser951 stabilize the inactive conformation of PSY1R.

  3. Direct activation of Transient Receptor Potential Vanilloid 1(TRPV1 by Diacylglycerol (DAG

    Directory of Open Access Journals (Sweden)

    Oh Seog

    2008-10-01

    Full Text Available Abstract The capsaicin receptor, known as transient receptor potential channel vanilloid subtype 1 (TRPV1, is activated by a wide range of noxious stimulants and putative ligands such as capsaicin, heat, pH, anandamide, and phosphorylation by protein kinase C (PKC. However, the identity of endogenous activators for TRPV1 under physiological condition is still debated. Here, we report that diacylglycerol (DAG directly activates TRPV1 channel in a membrane-delimited manner in rat dorsal root ganglion (DRG neurons. 1-oleoyl-2-acetyl-sn-glycerol (OAG, a membrane-permeable DAG analog, elicited intracellular Ca2+ transients, cationic currents and cobalt uptake that were blocked by TRPV1-selective antagonists, but not by inhibitors of PKC and DAG lipase in rat DRG neurons or HEK 293 cells heterologously expressing TRPV1. OAG induced responses were about one fifth of capsaicin induced signals, suggesting that OAG displays partial agonism. We also found that endogenously produced DAG can activate rat TRPV1 channels. Mutagenesis of rat TRPV1 revealed that DAG-binding site is at Y511, the same site for capsaicin binding, and PtdIns(4,5P2binding site may not be critical for the activation of rat TRPV1 by DAG in heterologous system. We propose that DAG serves as an endogenous ligand for rat TRPV1, acting as an integrator of Gq/11-coupled receptors and receptor tyrosine kinases that are linked to phospholipase C.

  4. Novel Role of Src in Priming Pyk2 Phosphorylation.

    Directory of Open Access Journals (Sweden)

    Ming Zhao

    Full Text Available Proline-rich tyrosine kinase 2 (Pyk2 is a member of the focal adhesion kinase (FAK family of non-receptor tyrosine kinases and plays an important role in diverse cellular events downstream of the integrin-family of receptors, including cell migration, proliferation and survival. Here, we have identified a novel role for Src kinase in priming Pyk2 phosphorylation and subsequent activation upon cell attachment on the integrin-ligand fibronectin. By using complementary methods, we show that Src activity is indispensable for the initial Pyk2 phosphorylation on the Y402 site observed in response to cell attachment. In contrast, the initial fibronectin-induced autophosphorylation of FAK in the homologous Y397 site occurs in a Src-independent manner. We demonstrate that the SH2-domain of Src is required for Src binding to Pyk2 and for Pyk2 phosphorylation at sites Y402 and Y579. Moreover, Y402 phosphorylation is a prerequisite for the subsequent Y579 phosphorylation. While this initial phosphorylation of Pyk2 by Src is independent of Pyk2 kinase activity, subsequent autophosphorylation of Pyk2 in trans is required for full Pyk2 phosphorylation and activation. Collectively, our studies reveal a novel function of Src in priming Pyk2 (but not FAK phosphorylation and subsequent activation downstream of integrins, and shed light on the signaling events that regulate the function of Pyk2.

  5. PTP1B Inhibition Causes Rac1 Activation by Enhancing Receptor Tyrosine Kinase Signaling

    Directory of Open Access Journals (Sweden)

    Ayako Tsuchiya

    2014-04-01

    Full Text Available Background/Aims: The present study investigated the signaling pathway underlying Rac1 activation induced by the linoleic acid derivative 8-[2-(2-pentyl-cyclopropylmethyl-cyclopropyl]-octanoic acid (DCP-LA. Methods: Activity of protein tyrosine phosphatase 1B (PTP1B was assayed under cell-free conditions. Western blot was carried out to quantify phosphorylation of insulin receptor substrate-1 (IRS-1 and Akt in PC-12 cells. Rac1 activity was monitored in the föerster resonance energy transfer (FRET analysis using living and fixed PC-12 cells. Results: DCP-LA markedly suppressed PTP1B activity in a concentration (100 pM-100 µM-dependent manner. In the DCP-LA binding assay, fluorescein-conjugated DCP-LA produced a single fluorescent signal band at 60 kDa, corresponding to the molecule of PTP1B, and the signal was attenuated or abolished by co-treatment or pretreatment with non-conjugated DCP-LA. DCP-LA significantly enhanced nerve growth factor (NGF-stimulated phosphorylation of IRS-1 at Tyr1222 and Akt1/2 at Thr308/309 and Ser473/474 in PC-12 cells. In the FRET analysis, DCP-LA significantly enhanced NGF-stimulated Rac1 activation, which is abrogated by the phosphatidylinositol 3 kinase (PI3K inhibitor wortmannin, the 3-phosphoinositide-dependent protein kinase-1 (PDK1 inhibitor BX912, or the Akt inhibitor MK2206. Conclusion: The results of the present study show that DCP-LA-induced PTP1B inhibition, possibly through its direct binding, causes Rac1 activation by enhancing a pathway along a receptor tyrosine kinase (RTK/IRS-1/PI3K/Akt/Rac1 axis.

  6. HSP20 phosphorylation and airway smooth muscle relaxation

    Directory of Open Access Journals (Sweden)

    Mariam Ba

    2009-06-01

    Full Text Available Mariam Ba1, Cherie A Singer1, Manoj Tyagi2, Colleen Brophy3, Josh E Baker4, Christine Cremo4, Andrew Halayko5, William T Gerthoffer21Department of Pharmacology, University of Nevada School of Medicine, Reno, NV, USA; 2Department of Biochemistry and Molecular Biology, University of South Alabama, Mobile, AL, USA; 3Harrington Department of Biochemistry, Arizona State University, Tempe, AZ, USA; 4Department of Biochemistry and Molecular Biology, University of Nevada, Reno, NV, USA; 5Departments of Physiology and Internal Medicine, University of Manitoba, Winnipeg, MB, CanadaAbstract: HSP20 (HSPB6 is a small heat shock protein expressed in smooth muscles that is hypothesized to inhibit contraction when phosphorylated by cAMP-dependent protein kinase. To investigate this hypothesis in airway smooth muscle (ASM we showed that HSP20 was constitutively expressed as well as being inducible in cultured hASM cells by treatment with 1 µM isoproterenol or 10 µM salmeterol. In contrast, a mixture of proinflammatory mediators (interleukin-1β, tumor necrosis factor α, and interferon γ inhibited expression of HSP20 by about 50% in 48 hours. To determine whether phosphorylation of HSP20 is sufficient to induce relaxation, canine tracheal smooth muscle was treated with a cell permeant phosphopeptide that mimics the phosphorylation of HSP20. The HSP20 phosphopeptide antagonized carbacholinduced contraction by 60% with no change in myosin light chain phosphorylation. Recombinant full length HSP20 inhibited skeletal actin binding to smooth muscle myosin subfragment 1 (S1, and recombinant cell permeant TAT-HSP20 S16D mutant reduced F-actin filaments in cultured hASM cells. Carbachol stimulation of canine tracheal smooth muscle tissue caused redistribution of HSP20 from large macromolecular complexes (200–500 kDa to smaller complexes (<60 kDa. The results are consistent with HSP20 expression and macromolecular structure being dynamically regulated in airway

  7. Cyclooxygenase-2 up-regulates CCR7 expression via AKT-mediated phosphorylation and activation of Sp1 in breast cancer cells.

    Science.gov (United States)

    Chuang, Chun-Wei; Pan, Mei-Ren; Hou, Ming-Feng; Hung, Wen-Chun

    2013-02-01

    Up-regulation of cyclooxygenase-2 (COX-2) is frequently found in human cancers and is significantly associated with tumor metastasis. Our previous results demonstrate that COX-2 and its metabolite prostaglandin E2 (PGE2) stimulate the expression of CCR7 chemokine receptor via EP2/EP4 receptors to promote lymphatic invasion in breast cancer cells. In this study, we address the underlying mechanism of COX-2/PGE2-induced CCR7 expression. We find that COX-2/PGE2 increase CCR7 expression via the AKT signaling pathway in breast cancer cells. Promoter deletion and mutation assays identify the Sp1 site located at the -60/-57 region of CCR7 gene promoter is critical for stimulation. Chromatin immunoprecipitation (ChIP) assay confirms that in vivo binding of Sp1 to human CCR7 promoter is increased by COX-2 and PGE2. Knockdown of Sp1 by shRNA reduces the induction of CCR7 by PGE2. We demonstrate for the first time that AKT may directly phosphorylate Sp1 at S42, T679, and S698. Phosphorylation-mimic Sp1 protein harboring S42D, T679D, and S698D mutation strongly activates CCR7 expression. In contrast, change of these three residues to alanine completely blocks the induction of CCR7 by PGE2. Pathological investigation demonstrates that CCR7 expression is strongly associated with phospho-AKT and Sp1 in 120 breast cancer tissues. Collectively, our results demonstrate that COX-2 up-regulates CCR7 expression via AKT-mediated phosphorylation and activation of Sp1 and this pathway is highly activated in metastatic breast cancer. Copyright © 2012 Wiley Periodicals, Inc.

  8. Interleukin-21 receptor deficiency increases the initial toll-like receptor 2 response but protects against joint pathology by reducing Th1 and Th17 cells during streptococcal cell wall arthritis.

    Science.gov (United States)

    Marijnissen, Renoud J; Roeleveld, Debbie M; Young, Deborah; Nickerson-Nutter, Cheryl; Abdollahi-Roodsaz, Shahla; Garcia de Aquino, Sabrina; van de Loo, Fons A J; van Spriel, Annemiek B; Boots, Annemieke M H; van den Berg, Wim B; Koenders, Marije I

    2014-04-01

    The cytokine interleukin-21 (IL-21) can have both proinflammatory and immunosuppressive effects. The purpose of this study was to investigate the potential dual role of IL-21 in experimental arthritis in relation to Th17 cells. Antigen-induced arthritis (AIA) and chronic streptococcal cell wall (SCW) arthritis were induced in IL-21 receptor-deficient (IL-21R(-/-) ) and wild-type mice. Knee joints, synovial tissue, and serum were analyzed for arthritis pathology and inflammatory markers. During AIA and chronic SCW arthritis, IL-21R deficiency protected against severe inflammation and joint destruction. This was accompanied by suppressed serum IgG1 levels and antigen-specific T cell responses. Levels of IL-17 were reduced during AIA, and synovial lymphocytes isolated during SCW arthritis for flow cytometry demonstrated that mainly IL-17+ interferon-γ (IFNγ)-positive T cells were reduced in IL-21R(-/-) mice. However, during the acute phases of SCW arthritis, significantly higher joint swelling scores were observed, consistent with enhanced tumor necrosis factor and IL-6 expression. Interestingly, IL-21R(-/-) mice were significantly less capable of up-regulating suppressor of cytokine signaling 1 (SOCS-1) and SOCS-3 messenger RNA. IL-21 stimulation also affected the Toll-like receptor 2 (TLR-2)/caspase recruitment domain 15 response to SCW fragments in vitro, indicating that impaired SOCS regulation in the absence of IL-21 signaling might contribute to the increased local activation during SCW arthritis. In contrast to the proinflammatory role of IL-21 in adaptive immunity, which drives IL-17+IFN+ cells and joint pathology during chronic experimental arthritis, IL-21 also has an important immunosuppressive role, presumably by inhibiting TLR signaling via SOCS-1 and SOCS-3. If this dual role of IL-21 in various immune processes is present in human disease, it could make IL-21 a difficult therapeutic target in rheumatoid arthritis. Copyright © 2014 by the American

  9. Syndecan-4 Phosphorylation Is a Control Point for Integrin Recycling

    Science.gov (United States)

    Morgan, Mark R.; Hamidi, Hellyeh; Bass, Mark D.; Warwood, Stacey; Ballestrem, Christoph; Humphries, Martin J.

    2013-01-01

    Summary Precise spatiotemporal coordination of integrin adhesion complex dynamics is essential for efficient cell migration. For cells adherent to fibronectin, differential engagement of α5β1 and αVβ3 integrins is used to elicit changes in adhesion complex stability, mechanosensation, matrix assembly, and migration, but the mechanisms responsible for receptor regulation have remained largely obscure. We identify phosphorylation of the membrane-intercalated proteoglycan syndecan-4 as an essential switch controlling integrin recycling. Src phosphorylates syndecan-4 and, by driving syntenin binding, leads to suppression of Arf6 activity and recycling of αVβ3 to the plasma membrane at the expense of α5β1. The resultant elevation in αVβ3 engagement promotes stabilization of focal adhesions. Conversely, abrogation of syndecan-4 phosphorylation drives surface expression of α5β1, destabilizes adhesion complexes, and disrupts cell migration. These data identify the dynamic spatiotemporal regulation of Src-mediated syndecan-4 phosphorylation as an essential switch controlling integrin trafficking and adhesion dynamics to promote efficient cell migration. PMID:23453597

  10. Chemerin C9 peptide induces receptor internalization through a clathrin-independent pathway

    Science.gov (United States)

    Zhou, Jun-xian; Liao, Dan; Zhang, Shuo; Cheng, Ni; He, Hui-qiong; Ye, Richard D

    2014-01-01

    Aim: The chemerin receptor CMKLR1 is one type of G protein-coupled receptors abundant in monocyte-derived dendritic cells and macrophages, which plays a key role in the entry of a subset of immunodeficiency viruses including HIV/SIV into lymphocytes and macrophages. The aim of this work was to investigate how CMKLR1 was internalized and whether its internalization affected cell signaling in vitro. Methods: Rat basophilic leukemia RBL-2H3 cells, HEK 293 cells, and HeLa cells were used. CMKLR1 internalization was visualized by confocal microscopy imaging or using a FACScan flow cytometer. Six potential phosphorylation sites (Ser337, Ser343, Thr352, Ser344, Ser347, and Ser350) in CMKLR1 were substituted with alanine using site-directed mutagenesis. Heterologous expression of wild type and mutant CMKLR1 allowed for functional characterization of endocytosis, Ca2+ flux and extracellular signal-regulated kinase (ERK) phosphorylation. Results: Chemerin and the chemerin-derived nonapeptide (C9) induced dose-dependent loss of cell surface CMKLR1-GFP fusion protein and increased its intracellular accumulation in HEK 293 cells and RBL-2H3 cells stably expressing CMKLR1. Up to 90% of CMKLR1 was internalized after treatment with C9 (1 μmol/L). By using different agents, it was demonstrated that clathrin-independent mechanism was involved in CMKLR1 internalization. Mutations in Ser343 for G protein-coupled receptor kinase phosphorylation and in Ser347 for PKC phosphorylation abrogated CMKLR1 internalization. Loss of CMKLR1 internalization partially enhanced the receptor signaling, as shown by increased Ca2+ flux and a shorter latency to peak level of ERK phosphorylation. Conclusion: CMKLR1 internalization occurs in a clathrin-independent manner, which negatively regulated the receptor-mediated Ca2+ flux and ERK phosphorylation. PMID:24658352

  11. Tyrosine phosphorylation in T cells is regulated by phosphatase activity: studies with phenylarsine oxide.

    OpenAIRE

    Garcia-Morales, P; Minami, Y; Luong, E; Klausner, R D; Samelson, L E

    1990-01-01

    Activation of T cells induces rapid tyrosine phosphorylation on the T-cell receptor zeta chain and other substrates. These phosphorylations can be regulated by a number of protein-tyrosine kinases (ATP: protein-tyrosine O-phosphotransferase, EC 2.7.1.112) and protein-tyrosine-phosphatases (protein-tyrosine-phosphate phosphohydrolase, EC 3.1.3.48). In this study, we demonstrate that phenylarsine oxide can inhibit tyrosine phosphatases while leaving tyrosine kinase function intact. We use this ...

  12. Glufosinate aerogenic exposure induces glutamate and IL-1 receptor dependent lung inflammation.

    Science.gov (United States)

    Maillet, Isabelle; Perche, Olivier; Pâris, Arnaud; Richard, Olivier; Gombault, Aurélie; Herzine, Ameziane; Pichon, Jacques; Huaux, Francois; Mortaud, Stéphane; Ryffel, Bernhard; Quesniaux, Valérie F J; Montécot-Dubourg, Céline

    2016-11-01

    Glufosinate-ammonium (GLA), the active component of an herbicide, is known to cause neurotoxicity. GLA shares structural analogy with glutamate. It is a powerful inhibitor of glutamine synthetase (GS) and may bind to glutamate receptors. Since these potentials targets of GLA are present in lung and immune cells, we asked whether airway exposure to GLA may cause lung inflammation in mice. A single GLA exposure (1 mg/kg) induced seizures and inflammatory cell recruitment in the broncho-alveolar space, and increased myeloperoxidase (MPO), inducible NO synthase (iNOS), interstitial inflammation and disruption of alveolar septae within 6-24 h. Interleukin 1β (IL-1β) was increased and lung inflammation depended on IL-1 receptor 1 (IL-1R1). We demonstrate that glutamate receptor pathway is central, since the N-methyl-D-aspartate (NMDA) receptor inhibitor MK-801 prevented GLA-induced lung inflammation. Chronic exposure (0.2 mg/kg 3× per week for 4 weeks) caused moderate lung inflammation and enhanced airway hyperreactivity with significant increased airway resistance. In conclusion, GLA aerosol exposure causes glutamate signalling and IL-1R-dependent pulmonary inflammation with airway hyperreactivity in mice. © 2016 The Author(s). published by Portland Press Limited on behalf of the Biochemical Society.

  13. Phosphorylation of mouse serine racemase regulates D-serine synthesis

    DEFF Research Database (Denmark)

    Foltyn, Veronika N; Zehl, Martin; Dikopoltsev, Elena

    2010-01-01

    Serine racemase (SR) catalyses the synthesis of the transmitter/neuromodulator D-serine, which plays a major role in synaptic plasticity and N-methyl D-aspartate receptor neurotoxicity. We now report that SR is phosphorylated at Thr71 and Thr227 as revealed by mass spectrometric analysis and in v...... with a phosphorylation-deficient SR mutant indicate that Thr71 phosphorylation increases SR activity, suggesting a novel mechanism for regulating D-serine production....

  14. IL-1 receptor-antagonist (IL-1Ra) knockout mice show anxiety-like behavior by aging.

    Science.gov (United States)

    Wakabayashi, Chisato; Numakawa, Tadahiro; Odaka, Haruki; Ooshima, Yoshiko; Kiyama, Yuji; Manabe, Toshiya; Kunugi, Hiroshi; Iwakura, Yoichiro

    2015-07-10

    Interleukin 1 (IL-1) plays a critical role in stress responses, and its mRNA is induced in the brain by restraint stress. Previously, we reported that IL-1 receptor antagonist (IL-1Ra) knockout (KO) mice, which lacked IL-1Ra molecules that antagonize the IL-1 receptor, showed anti-depression-like behavior via adrenergic modulation at the age of 8 weeks. Here, we report that IL-1Ra KO mice display an anxiety-like phenotype that is induced spontaneously by aging in the elevated plus-maze (EPM) test. This anxiety-like phenotype was improved by the administration of diazepam. The expression of the anxiety-related molecule glucocorticoid receptor (GR) was significantly reduced in 20-week-old but not in 11-week-old IL-1Ra KO mice compared to wild-type (WT) littermates. The expression of the mineralocorticoid receptor (MR) was not altered between IL-1Ra KO mice and WT littermates at either 11 or 20 weeks old. Analysis of monoamine concentration in the hippocampus revealed that tryptophan, the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), and the dopamine metabolite homovanillic acid (HVA) were significantly increased in 20-week-old IL-1Ra KO mice compared to littermate WT mice. These findings strongly suggest that the anxiety-like behavior observed in older mice was caused by the complicated alteration of monoamine metabolism and/or GR expression in the hippocampus. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. The emerging role of interleukin (IL)-1 in the pathogenesis and treatment of inflammatory and degenerative eye diseases.

    Science.gov (United States)

    Fabiani, Claudia; Sota, Jurgen; Tosi, Gian Marco; Franceschini, Rossella; Frediani, Bruno; Galeazzi, Mauro; Rigante, Donato; Cantarini, Luca

    2017-10-01

    Interleukin (IL)-1 plays a key role in the pathogenesis and thereafter in the search for specific treatments of different inflammatory and degenerative eye diseases. Indeed, an overactivity of IL-1 might be an initiating factor for many immunopathologic sceneries in the eye, as proven by the efficacy of the specific IL-1 blockade in different ocular diseases. For instance, the uveitis in monogenic autoinflammatory disorders, such as Blau syndrome and cryopyrin-associated periodic syndrome, or in complex polygenic autoinflammatory disorders, such as Behçet's disease, has been successfully treated with IL-1 blockers. Similarly, therapy with the IL-1 receptor antagonist anakinra has proven successful also in scleritis and episcleritis in the context of different rheumatic conditions. Moreover, interesting findings deriving from animal models of ocular disease have set a rational basis from a therapeutic viewpoint to manage patients also with dry eye disease and a broadening number of ocular inflammatory and degenerative conditions, which start from an imbalance between IL-1 and its receptor antagonist.

  16. Potent homocysteine-induced ERK phosphorylation in cultured neurons depends on self-sensitization via system Xc-

    International Nuclear Information System (INIS)

    Gu Li; Hu Xiaoling; Xue Zhanxia; Yang Jun; Wan Lishu; Ren Yan; Hertz, Leif; Peng Liang

    2010-01-01

    Homocysteine is increased during pathological conditions, endangering vascular and cognitive functions, and elevated homocysteine during pregnancy may be correlated with an increased incidence of schizophrenia in the offspring. This study showed that millimolar homocysteine concentrations in saline medium cause phosphorylation of extracellular-signal regulated kinases 1 and 2 (ERK 1/2 ) in cerebellar granule neurons, inhibitable by metabotropic but not ionotropic glutamate receptor antagonists. These findings are analogous to observations by , that similar concentrations cause neuronal death. However, these concentrations are much higher than those occurring clinically during hyperhomocysteinemia. It is therefore important that a ∼ 10-fold increase in potency occurred in the presence of the glutamate precursor glutamine, when ERK 1/2 phosphorylation became inhibitable by NMDA or non-NMDA antagonists and dependent upon epidermal growth factor (EGF) receptor transactivation. However, glutamate release to the medium was reduced, suggesting that reversal of the cystine/glutamate antiporter, system X c - could be involved in potentiation of the response by causing a localized release of initially accumulated homocysteine. In agreement with this hypothesis further enhancement of ERK 1/2 phosphorylation occurred in the additional presence of cystine. Pharmacological inhibition of system X c - prevented the effect of micromolar homocysteine concentrations, and U0126-mediated inhibition of ERK 1/2 phosphorylation enhanced homocysteine-induced death. In conclusion, homocysteine interacts with system X c - like quisqualate (Venkatraman et al. 1994), by 'self-sensitization' with initial accumulation and subsequent release in exchange with cystine and/or glutamate, establishing high local homocysteine concentrations, which activate adjacent ionotropic glutamate receptors and cause neurotoxicity.

  17. The SRC homology 2 domain of Rin1 mediates its binding to the epidermal growth factor receptor and regulates receptor endocytosis.

    Science.gov (United States)

    Barbieri, M Alejandro; Kong, Chen; Chen, Pin-I; Horazdovsky, Bruce F; Stahl, Philip D

    2003-08-22

    Activated epidermal growth factor receptors (EGFRs) recruit intracellular proteins that mediate receptor signaling and endocytic trafficking. Rin1, a multifunctional protein, has been shown to regulate EGFR internalization (1). Here we show that EGF stimulation induces a specific, rapid, and transient membrane recruitment of Rin1 and that recruitment is dependent on the Src homology 2 (SH2) domain of Rin1. Immunoprecipitation of EGFR is accompanied by co-immunoprecipitation of Rin1 in a time- and ligand-dependent manner. Association of Rin1 and specifically the SH2 domain of Rin1 with the EGFR was dependent on tyrosine phosphorylation of the intracellular domain of the EGFR. The recruitment of Rin1, observed by light microscopy, indicated that although initially cytosolic, Rin1 was recruited to both plasma membrane and endosomes following EGF addition. Moreover, the expression of the SH2 domain of Rin1 substantially impaired the internalization of EGF without affecting internalization of transferrin. Finally, we found that Rin1 co-immunoprecipitated with a number of tyrosine kinase receptors but not with cargo endocytic receptors. These results indicate that Rin1 provides a link via its SH2 domain between activated tyrosine kinase receptors and the endocytic pathway through the recruitment and activation of Rab5a.

  18. The insulin receptor substrate 1 associates with phosphotyrosine phosphatase SHPTP2 in liver and muscle of rats

    Directory of Open Access Journals (Sweden)

    Lima M.H.M.

    1998-01-01

    Full Text Available Insulin stimulates the tyrosine kinase activity of its receptor resulting in the phosphorylation of its cytosolic substrate, insulin receptor substrate-1 (IRS-1 which, in turn, associates with proteins containing SH2 domains. It has been shown that IRS-1 associates with the tyrosine phosphatase SHPTP2 in cell cultures. While the effect of the IRS-1/SHPTP2 association on insulin signal transduction is not completely known, this association may dephosphorylate IRS-1 and may play a critical role in the mitogenic actions of insulin. However, there is no physiological demonstration of this pathway of insulin action in animal tissues. In the present study we investigated the ability of insulin to induce association between IRS-1 and SHPTP2 in liver and muscle of intact rats, by co-immunoprecipitation with anti-IRS-1 antibody and anti-SHPTP2 antibody. In both tissues there was an increase in IRS-1 association with SHPTP2 after insulin stimulation. This association occurred when IRS-1 had the highest level of tyrosine phosphorylation and the decrease in this association was more rapid than the decrease in IRS-1 phosphorylation levels. The data provide evidence against the participation of SHPTP2 in IRS-1 dephosphorylation in rat tissues, and suggest that the insulin signal transduction pathway in rat tissues is related mainly to the mitogenic effects of the hormone.

  19. Insight into Phosphatidylinositol-Dependent Membrane Localization of the Innate Immune Adaptor Protein Toll/Interleukin 1 Receptor Domain-Containing Adaptor Protein

    Directory of Open Access Journals (Sweden)

    Mahesh Chandra Patra

    2018-01-01

    Full Text Available The toll/interleukin 1 receptor (TIR domain-containing adaptor protein (TIRAP plays an important role in the toll-like receptor (TLR 2, TLR4, TLR7, and TLR9 signaling pathways. TIRAP anchors to phosphatidylinositol (PI 4,5-bisphosphate (PIP2 on the plasma membrane and PI (3,4,5-trisphosphate (PIP3 on the endosomal membrane and assists in recruitment of the myeloid differentiation primary response 88 protein to activated TLRs. To date, the structure and mechanism of TIRAP’s membrane association are only partially understood. Here, we modeled an all-residue TIRAP dimer using homology modeling, threading, and protein–protein docking strategies. Molecular dynamics simulations revealed that PIP2 creates a stable microdomain in a dipalmitoylphosphatidylcholine bilayer, providing TIRAP with its physiologically relevant orientation. Computed binding free energy values suggest that the affinity of PI-binding domain (PBD for PIP2 is stronger than that of TIRAP as a whole for PIP2 and that the short PI-binding motif (PBM contributes to the affinity between PBD and PIP2. Four PIP2 molecules can be accommodated by distinct lysine-rich surfaces on the dimeric PBM. Along with the known PI-binding residues (K15, K16, K31, and K32, additional positively charged residues (K34, K35, and R36 showed strong affinity toward PIP2. Lysine-to-alanine mutations at the PI-binding residues abolished TIRAP’s affinity for PIP2; however, K34, K35, and R36 consistently interacted with PIP2 headgroups through hydrogen bond (H-bond and electrostatic interactions. TIRAP exhibited a PIP2-analogous intermolecular contact and binding affinity toward PIP3, aided by an H-bond network involving K34, K35, and R36. The present study extends our understanding of TIRAP’s membrane association, which could be helpful in designing peptide decoys to block TLR2-, TLR4-, TLR7-, and TLR9-mediated autoimmune diseases.

  20. DIFFERENTIAL BINDING OF HUMAN INTERLEUKIN-1 (IL-1) RECEPTOR ANTAGONIST TO NATURAL AND RECOMBINANT SOLUBLE AND CELLULAR IL-1 TYPE-I RECEPTORS

    DEFF Research Database (Denmark)

    Svenson, Morten; Nedergaard, Susanne; Heegaard, Peter M. H.

    1995-01-01

    antagonist (IL-1ra). Recombinant soluble human IL-1RI expressed in COS cells (sIL-1RI) consists of the extracellular part of the receptor and binds all three known IL-1 species but preferentially to IL-1ra. We further characterized the sizes and binding of IL-1raBF and sIL-1RI to IL-1ra by polyacrylamide gel...... electrophoresis in the presence of sodium dodecylsulfate, ligand binding interference analyses, N-glycosidase treatment, concanavalin A affinity chromatography, and with the use of monoclonal antibodies (mAb) to human recombinant IL-1ra. We also evaluated the binding of IL-1ra to cellular IL-1RI on MRC5...... binding of both molecules to IL-1ra. Both factors blocked binding of IL-1ra to cellular IL-1RI, as did mAb to IL-1ra, but the sites on IL-1ra which bound to the mAb, and to IL-1raBF and sIL-1RI, differed. We conclude that there are important differences between the natural and recombinant forms of soluble...

  1. Histone H1 phosphorylation is associated with transcription by RNA polymerases I and II

    Science.gov (United States)

    Zheng, Yupeng; John, Sam; Pesavento, James J.; Schultz-Norton, Jennifer R.; Schiltz, R. Louis; Baek, Sonjoon; Nardulli, Ann M.; Hager, Gordon L.; Kelleher, Neil L.

    2010-01-01

    Histone H1 phosphorylation affects chromatin condensation and function, but little is known about how specific phosphorylations impact the function of H1 variants in higher eukaryotes. In this study, we show that specific sites in H1.2 and H1.4 of human cells are phosphorylated only during mitosis or during both mitosis and interphase. Antisera generated to individual H1.2/H1.4 interphase phosphorylations reveal that they are distributed throughout nuclei and enriched in nucleoli. Moreover, interphase phosphorylated H1.4 is enriched at active 45S preribosomal RNA gene promoters and is rapidly induced at steroid hormone response elements by hormone treatment. Our results imply that site-specific interphase H1 phosphorylation facilitates transcription by RNA polymerases I and II and has an unanticipated function in ribosome biogenesis and control of cell growth. Differences in the numbers, structure, and locations of interphase phosphorylation sites may contribute to the functional diversity of H1 variants. PMID:20439994

  2. Activation of the HMGB1-RAGE axis upregulates TH expression in dopaminergic neurons via JNK phosphorylation.

    Science.gov (United States)

    Kim, Soo Jeong; Ryu, Min Jeong; Han, Jeongsu; Jang, Yunseon; Kim, Jungim; Lee, Min Joung; Ryu, Ilhwan; Ju, Xianshu; Oh, Eungseok; Chung, Woosuk; Kweon, Gi Ryang; Heo, Jun Young

    2017-11-04

    The derangement of tyrosine hydroxylase (TH) activity reduces dopamine synthesis and is implicated in the pathogenesis of Parkinson's disease. However, the extracellular modulator and intracellular regulatory mechanisms of TH have yet to be identified. Recently, high-mobility group box 1 (HMGB1) was reported to be actively secreted from glial cells and is regarded as a mediator of dopaminergic neuronal loss. However, the mechanism for how HMGB1 affects TH expression, particularly through the receptor for advanced glycation endproducts (RAGE), has not yet been investigated. We found that recombinant HMGB1 (rHMGB1) upregulates TH mRNA expression via simultaneous activation of JNK phosphorylation, and this induction of TH expression is blocked by inhibitors of RAGE and JNK. To investigate how TH expression levels change through the HMGB1-RAGE axis as a result of MPP + toxicity, we co-treated SN4741 dopaminergic cells with MPP + and rHMGB1. rHMGB1 blocked the reduction of TH mRNA following MPP + treatment without altering cell survival rates. Our results suggest that HMGB1 upregulates TH expression to maintain dopaminergic neuronal function via activating RAGE, which is dependent on JNK phosphorylation. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Fatty acid represses insulin receptor gene expression by impairing HMGA1 through protein kinase Cε

    International Nuclear Information System (INIS)

    Dey, Debleena; Bhattacharya, Anirban; Roy, SibSankar; Bhattacharya, Samir

    2007-01-01

    It is known that free fatty acid (FFA) contributes to the development of insulin resistance and type2 diabetes. However, the underlying mechanism in FFA-induced insulin resistance is still unclear. In the present investigation we have demonstrated that palmitate significantly (p < 0.001) inhibited insulin-stimulated phosphorylation of PDK1, the key insulin signaling molecule. Consequently, PDK1 phosphorylation of plasma membrane bound PKCε was also inhibited. Surprisingly, phosphorylation of cytosolic PKCε was greatly stimulated by palmitate; this was then translocated to the nuclear region and associated with the inhibition of insulin receptor (IR) gene transcription. A PKCε translocation inhibitor peptide, εV1, suppressed this inhibitory effect of palmitate, suggesting requirement of phospho-PKCε migration to implement palmitate effect. Experimental evidences indicate that phospho-PKCε adversely affected HMGA1. Since HMGA1 regulates IR promoter activity, expression of IR gene was impaired causing reduction of IR on cell surface and that compromises with insulin sensitivity

  4. Common elements in interleukin 4 and insulin signaling pathways in factor-dependent hematopoietic cells.

    Science.gov (United States)

    Wang, L M; Keegan, A D; Li, W; Lienhard, G E; Pacini, S; Gutkind, J S; Myers, M G; Sun, X J; White, M F; Aaronson, S A

    1993-05-01

    Interleukin 4 (IL-4), insulin, and insulin-like growth factor I (IGF-I) efficiently induced DNA synthesis in the IL-3-dependent murine myeloid cell lines FDC-P1 and FDC-P2. Although these factors could not individually sustain long-term growth of these lines, a combination of IL-4 with either insulin or IGF-I did support continuous growth. The principal tyrosine-phosphorylated substrate observed in FDC cells stimulated with IL-4, previously designated 4PS, was of the same size (170 kDa) as the major substrate phosphorylated in response to insulin or IGF-I. These substrates had phosphopeptides of the same size when analyzed by digestion with Staphylococcus aureus V8 protease, and each tightly associated with the 85-kDa component of phosphatidylinositol 3-kinase after factor stimulation. IRS-1, the principal substrate phosphorylated in response to insulin or IGF-I stimulation in nonhematopoietic cells, is similar in size to 4PS. However, anti-IRS-1 antibodies failed to efficiently precipitate 4PS, and some phosphopeptides generated by V8 protease digestion of IRS-1 were distinct in size from the phosphopeptides of 4PS. Nevertheless, IL-4, insulin, and IGF-I were capable of stimulating tyrosine phosphorylation of IRS-1 in FDC cells that expressed this substrate as a result of transfection. These findings indicate that (i) IL-4, insulin, and IGF-I use signal transduction pathways in FDC lines that have at least one major feature in common, the rapid tyrosine phosphorylation of 4PS, and (ii) insulin and IGF-I stimulation of hematopoietic cell lines leads to the phosphorylation of a substrate that may be related to but is not identical to IRS-1.

  5. Tyrosine Phosphorylation of Rac1: A Role in Regulation of Cell Spreading

    Science.gov (United States)

    Chang, Fumin; Lemmon, Christopher; Lietha, Daniel; Eck, Michael; Romer, Lewis

    2011-01-01

    Rac1 influences a multiplicity of vital cellular- and tissue-level control functions, making it an important candidate for targeted therapeutics. The activity of the Rho family member Cdc42 has been shown to be modulated by tyrosine phosphorylation at position 64. We therefore investigated consequences of the point mutations Y64F and Y64D in Rac1. Both mutations altered cell spreading from baseline in the settings of wild type, constitutively active, or dominant negative Rac1 expression, and were accompanied by differences in Rac1 targeting to focal adhesions. Rac1-Y64F displayed increased GTP-binding, increased association with βPIX, and reduced binding with RhoGDI as compared with wild type Rac1. Rac1-Y64D had less binding to PAK than Rac1-WT or Rac1-64F. In vitro assays demonstrated that Y64 in Rac1 is a target for FAK and Src. Taken together, these data suggest a mechanism for the regulation of Rac1 activity by non-receptor tyrosine kinases, with consequences for membrane extension. PMID:22163037

  6. Targeting non-small cell lung cancer cells by dual inhibition of the insulin receptor and the insulin-like growth factor-1 receptor.

    Directory of Open Access Journals (Sweden)

    Emma E Vincent

    Full Text Available Phase III trials of the anti-insulin-like growth factor-1 receptor (IGF1R antibody figitumumab in non-small cell lung cancer (NSCLC patients have been discontinued owing to lack of survival benefit. We investigated whether inhibition of the highly homologous insulin receptor (IR in addition to the IGF1R would be more effective than inhibition of the IGF1R alone at preventing the proliferation of NSCLC cells. Signalling through IGF1R and IR in the NSCLC cell lines A549 and Hcc193 was stimulated by a combination of IGF1, IGF2 and insulin. It was inhibited by antibodies that block ligand binding, αIR3 (IGF1R and IR47-9 (IR, and by the ATP-competitive small molecule tyrosine kinase inhibitors AZ12253801 and NVPAWD742 which inhibit both IGF1R and IR tyrosine kinases. The effect of inhibitors was determined by an anchorage-independent proliferation assay and by analysis of Akt phosphorylation. In Hcc193 cells the reduction in cell proliferation and Akt phosphorylation due to anti-IGF1R antibody was enhanced by antibody-mediated inhibition of the IR whereas in A549 cells, with a relatively low IR:IGF1R expression ratio, it was not. In each cell line proliferation and Akt phosphorylation were more effectively inhibited by AZ12253801 and NVPAWD742 than by combined αIR3 and IR47-9. When the IGF1R alone is inhibited, unencumbered signalling through the IR can contribute to continued NSCLC cell proliferation. We conclude that small molecule inhibitors targeting both the IR and IGF1R more effectively reduce NSCLC cell proliferation in a manner independent of the IR:IGF1R expression ratio, providing a therapeutic rationale for the treatment of this disease.

  7. Radiolabelled Interleukin-12, a new radiopharmaceutical for imaging chronic TH1-mediated inflammation

    International Nuclear Information System (INIS)

    Annovazzi, A.; Cornelissen, B.; Slegers, G.; D'Alessandria, C.; Bonanno, E.; Signore, A.

    2003-01-01

    Full text: Cytokines have been extensively used to image inflammatory processes (IL1, IL2, IL6, IL8 and others). In particular, for chronic inflammation, labelled IL2 has been successfully used although it binds to both T helper-1 (Th1) and T helper-2 (Th2) cells. In order to increase the specificity for the detection of Th1-mediated inflammation (i.e. organ specific autoimmune diseases), we considered the possibility to label the interleukin-12 (IL12), an heterodimeric cytokine which play a key role in the development of Th1 cells. Objectives: Aim of the present study was to label the Interleukin-12 with 123I and to test its potential as radiopharmaceutical to image chronic inflammatory disorders. Methods: IL12 was labelled with 123I using the IODOGEN method and purified by gel-filtration chromatography on PD10 columns. 123I-IL12 biodistribution was studied in normal NMRI mice at 1,2 and 4h after injection. A mouse model of autoimmune chronic colitis induced by intrarectal instillation of Trinitrobenzen sulfonic acid (TNBS) has been used for imaging purposes and, as controls, mice receiving 50% ethanol in phosphate buffer saline. Results: 123I-IL12 labelling efficiency ranged between 52-65%. Results of biodistribution studies showed a rapid plasma clearance and a main renal excretion route. No significant 123I-IL12 accumulation in major organs and tissues was observed. 123I-IL12 accumulated in areas of chronic inflamed colon as assessed by histological examination. No significant 123I-IL12 uptake is detectable in mice with acute colitis, confirming the specificity of 123IIL12 binding on its receptors expressed on T-lymphocytes. Conclusions: We conclude that this cytokine could be used for the in vivo imaging of Th1 mediated inflammatory processes. (author)

  8. Active inhibitor-1 maintains protein hyper-phosphorylation in aging hearts and halts remodeling in failing hearts.

    Science.gov (United States)

    Pritchard, Tracy J; Kawase, Yoshiaki; Haghighi, Kobra; Anjak, Ahmad; Cai, Wenfeng; Jiang, Min; Nicolaou, Persoulla; Pylar, George; Karakikes, Ioannis; Rapti, Kleopatra; Rubinstein, Jack; Hajjar, Roger J; Kranias, Evangelia G

    2013-01-01

    Impaired sarcoplasmic reticulum calcium cycling and depressed contractility are key characteristics in heart failure. Defects in sarcoplasmic reticulum function are characterized by decreased SERCA2a Ca-transport that is partially attributable to dephosphorylation of its regulator phospholamban by increased protein phosphatase 1 activity. Inhibition of protein phosphatase 1 through activation of its endogenous inhibitor-1 has been shown to enhance cardiac Ca-handling and contractility as well as protect from pathological stress remodeling in young mice. In this study, we assessed the long-term effects of inducible expression of constitutively active inhibitor-1 in the adult heart and followed function and remodeling through the aging process, up to 20 months. Mice with inhibitor-1 had normal survival and similar function to WTs. There was no overt remodeling as evidenced by measures of left ventricular end-systolic and diastolic diameters and posterior wall dimensions, heart weight to tibia length ratio, and histology. Higher phosphorylation of phospholamban at both Ser16 and Thr17 was maintained in aged hearts with active inhibitor-1, potentially offsetting the effects of elevated Ser2815-phosphorylation in ryanodine receptor, as there were no increases in arrhythmias under stress conditions in 20-month old mice. Furthermore, long-term expression of active inhibitor-1 via recombinant adeno-associated virus type 9 gene transfer in rats with pressure-overload induced heart failure improved function and prevented remodeling, associated with increased phosphorylation of phospholamban at Ser16 and Thr17. Thus, chronic inhibition of protein phosphatase 1, through increases in active inhibitor-1, does not accelerate age-related cardiomyopathy and gene transfer of this molecule in vivo improves function and halts remodeling in the long term.

  9. The Innate Immune Receptor NLRX1 Functions as a Tumor Suppressor by Reducing Colon Tumorigenesis and Key Tumor-Promoting Signals

    Directory of Open Access Journals (Sweden)

    A. Alicia Koblansky

    2016-03-01

    Full Text Available NOD-like receptor (NLR proteins are intracellular innate immune sensors/receptors that regulate immunity. This work shows that NLRX1 serves as a tumor suppressor in colitis-associated cancer (CAC and sporadic colon cancer by keeping key tumor promoting pathways in check. Nlrx1−/− mice were highly susceptible to CAC, showing increases in key cancer-promoting pathways including nuclear factor κB (NF-κB, mitogen-activated protein kinase (MAPK, signal transducer and activator of transcription 3 (STAT3, and interleukin 6 (IL-6. The tumor-suppressive function of NLRX1 originated primarily from the non-hematopoietic compartment. This prompted an analysis of NLRX1 function in the Apcmin/+ genetic model of sporadic gastrointestinal cancer. NLRX1 attenuated Apcmin/+ colon tumorigenesis, cellular proliferation, NF-κB, MAPK, STAT3 activation, and IL-6 levels. Application of anti-interleukin 6 receptor (IL6R antibody therapy reduced tumor burden, increased survival, and reduced STAT3 activation in Nlrx1−/−Apcmin/+ mice. As an important clinical correlate, human colon cancer samples expressed lower levels of NLRX1 than healthy controls in multiple patient cohorts. These data implicate anti-IL6R as a potential personalized therapy for colon cancers with reduced NLRX1.

  10. Impaired degradation followed by enhanced recycling of epidermal growth factor receptor caused by hypo-phosphorylation of tyrosine 1045 in RBE cells

    International Nuclear Information System (INIS)

    Gui, Anping; Kobayashi, Akira; Motoyama, Hiroaki; Kitazawa, Masato; Takeoka, Michiko; Miyagawa, Shinichi

    2012-01-01

    Since cholangiocarcinoma has a poor prognosis, several epidermal growth factor receptor (EGFR)-targeted therapies with antibody or small molecule inhibitor treatment have been proposed. However, their effect remains limited. The present study sought to understand the molecular genetic characteristics of cholangiocarcinoma related to EGFR, with emphasis on its degradation and recycling. We evaluated EGFR expression and colocalization by immunoblotting and immunofluorescence, cell surface EGFR expression by fluorescence-activated cell sorting (FACS), and EGFR ubiquitination and protein binding by immunoprecipitation in the human cholangiocarcinoma RBE and immortalized cholangiocyte MMNK-1 cell lines. Monensin treatment and Rab11a depletion by siRNA were adopted for inhibition of EGFR recycling. Upon stimulation with EGF, ligand-induced EGFR degradation was impaired and the expression of phospho-tyrosine 1068 and phospho-p44/42 MAPK was sustained in RBE cells as compared with MMNK-1 cells. In RBE cells, the process of EGFR sorting for lysosomal degradation was blocked at the early endosome stage, and non-degradated EGFR was recycled to the cell surface. A disrupted association between EGFR and the E3 ubiquitin ligase c-Cbl, as well as hypo-phosphorylation of EGFR at tyrosine 1045 (Tyr1045), were also observed in RBE cells. In RBE cells, up-regulation of EGFR Tyr1045 phosphorylation is a potentially useful molecular alteration in EGFR-targeted therapy. The combination of molecular-targeted therapy determined by the characteristics of individual EGFR phosphorylation events and EGFR recycling inhibition show promise in future treatments of cholangiocarcinoma

  11. Charomers-Interleukin-6 Receptor Specific Aptamers for Cellular Internalization and Targeted Drug Delivery.

    Science.gov (United States)

    Hahn, Ulrich

    2017-12-06

    Interleukin-6 (IL-6) is a key player in inflammation and the main factor for the induction of acute phase protein biosynthesis. Further to its central role in many aspects of the immune system, IL-6 regulates a variety of homeostatic processes. To interfere with IL-6 dependent diseases, such as various autoimmune diseases or certain cancers like multiple myeloma or hepatocellular carcinoma associated with chronic inflammation, it might be a sensible strategy to target human IL-6 receptor (hIL-6R) presenting cells with aptamers. We therefore have selected and characterized different DNA and RNA aptamers specifically binding IL-6R. These IL-6R aptamers, however, do not interfere with the IL-6 signaling pathway but are internalized with the receptor and thus can serve as vehicles for the delivery of different cargo molecules like therapeutics. We succeeded in the construction of a chlorin e6 derivatized aptamer to be delivered for targeted photodynamic therapy (PDT). Furthermore, we were able to synthesize an aptamer intrinsically comprising the cytostatic 5-Fluoro-2'-deoxy-uridine for targeted chemotherapy. The α6β4 integrin specific DNA aptamer IDA, also selected in our laboratory is internalized, too. All these aptamers can serve as vehicles for targeted drug delivery into cells. We call them charomers-in memory of Charon, the ferryman in Greek mythology, who ferried the deceased into the underworld.

  12. Phosphorylation of Nanog is Essential to Regulate Bmi1 and Promote Tumorigenesis

    Science.gov (United States)

    Xie, Xiujie; Piao, Longzhu; Cavey, Greg S.; Old, Matthew; Teknos, Theodoros N.; Mapp, Anna K; Pan, Quintin

    2014-01-01

    Emerging evidence indicates that Nanog is intimately involved in tumorigenesis in part through regulation of the cancer initiating cell population. However, the regulation and role of Nanog in tumorigenesis are still poorly understood. In this study, human Nanog was identified to be phosphorylated by human PKCε at multiple residues including T200 and T280. Our work indicated that phosphorylation at T200 and T280 modulates Nanog function through several regulatory mechanisms. Results with phosphorylation-insensitive and phosphorylation-mimetic mutant Nanog revealed that phosphorylation at T200 and T280 enhance Nanog protein stability. Moreover, phosphorylation-insensitive T200A and T280A mutant Nanog had a dominant-negative function to inhibit endogenous Nanog transcriptional activity. Inactivation of Nanog was due to impaired homodimerization, DNA binding, promoter occupancy, and p300, a transcriptional co-activator, recruitment resulting in a defect in target gene promoter activation. Ectopic expression of phosphorylation-insensitive T200A or T280A mutant Nanog reduced cell proliferation, colony formation, invasion, migration, and the cancer initiating cell population in head and neck squamous cell carcinoma (HNSCC) cells. The in vivo cancer initiating ability was severely compromised in HNSCC cells expressing phosphorylation-insensitive T200A or T280A mutant Nanog; 87.5% (14/16), 12.5% (1/8), and 0% (0/8) for control, T200A, and T280A, respectively. Nanog occupied the Bmi1 promoter to directly transactivate and regulate Bmi1. Genetic ablation and rescue experiments demonstrated that Bmi1 is a critical downstream signaling node for the pleiotropic, pro-oncogenic effects of Nanog. Taken together, our study revealed, for the first time, that post-translational phosphorylation of Nanog is essential to regulate Bmi1 and promote tumorigenesis. PMID:23708658

  13. Insulin receptors mediate growth effects in cultured fetal neurons. II. Activation of a protein kinase that phosphorylates ribosomal protein S6

    International Nuclear Information System (INIS)

    Heidenreich, K.A.; Toledo, S.P.

    1989-01-01

    As an initial attempt to identify early steps in insulin action that may be involved in the growth responses of neurons to insulin, we investigated whether insulin receptor activation increases the phosphorylation of ribosomal protein S6 in cultured fetal neurons and whether activation of a protein kinase is involved in this process. When neurons were incubated for 2 h with 32Pi, the addition of insulin (100 ng/ml) for the final 30 min increased the incorporation of 32Pi into a 32K microsomal protein. The incorporation of 32Pi into the majority of other neuronal proteins was unaltered by the 30-min exposure to insulin. Cytosolic extracts from insulin-treated neurons incubated in the presence of exogenous rat liver 40S ribosomes and [gamma-32P]ATP displayed a 3- to 8-fold increase in the phosphorylation of ribosomal protein S6 compared to extracts from untreated cells. Inclusion of cycloheximide during exposure of the neurons to insulin did not inhibit the increased cytosolic kinase activity. Activation of S6 kinase activity by insulin was dose dependent (seen at insulin concentration as low as 0.1 ng/ml) and reached a maximum after 20 min of incubation. Addition of phosphatidylserine, diolein, and Ca2+ to the in vitro kinase reaction had no effect on the phosphorylation of ribosomal protein S6. Likewise, treatment of neurons with (Bu)2cAMP did not alter the phosphorylation of ribosomal protein S6 by neuronal cytosolic extracts. We conclude that insulin activates a cytosolic protein kinase that phosphorylates ribosomal S6 in neurons and is distinct from protein kinase-C and cAMP-dependent protein kinase. Stimulation of this kinase may play a role in insulin signal transduction in neurons

  14. Phosphorylation of Human Metapneumovirus M2-1 Protein Upregulates Viral Replication and Pathogenesis.

    Science.gov (United States)

    Cai, Hui; Zhang, Yu; Lu, Mijia; Liang, Xueya; Jennings, Ryan; Niewiesk, Stefan; Li, Jianrong

    2016-08-15

    Human metapneumovirus (hMPV) is a major causative agent of upper- and lower-respiratory-tract infections in infants, the elderly, and immunocompromised individuals worldwide. Like all pneumoviruses, hMPV encodes the zinc binding protein M2-1, which plays important regulatory roles in RNA synthesis. The M2-1 protein is phosphorylated, but the specific role(s) of the phosphorylation in viral replication and pathogenesis remains unknown. In this study, we found that hMPV M2-1 is phosphorylated at amino acid residues S57 and S60. Subsequent mutagenesis found that phosphorylation is not essential for zinc binding activity and oligomerization, whereas inhibition of zinc binding activity abolished the phosphorylation and oligomerization of the M2-1 protein. Using a reverse genetics system, recombinant hMPVs (rhMPVs) lacking either one or both phosphorylation sites in the M2-1 protein were recovered. These recombinant viruses had a significant decrease in both genomic RNA replication and mRNA transcription. In addition, these recombinant viruses were highly attenuated in cell culture and cotton rats. Importantly, rhMPVs lacking phosphorylation in the M2-1 protein triggered high levels of neutralizing antibody and provided complete protection against challenge with wild-type hMPV. Collectively, these data demonstrated that phosphorylation of the M2-1 protein upregulates hMPV RNA synthesis, replication, and pathogenesis in vivo The pneumoviruses include many important human and animal pathogens, such as human respiratory syncytial virus (hRSV), hMPV, bovine RSV, and avian metapneumovirus (aMPV). Among these viruses, hRSV and hMPV are the leading causes of acute respiratory tract infection in infants and children. Currently, there is no antiviral or vaccine to combat these diseases. All known pneumoviruses encode a zinc binding protein, M2-1, which is a transcriptional antitermination factor. In this work, we found that phosphorylation of M2-1 is essential for virus

  15. Anti-interleukin-2 receptor antibodies—basiliximab and daclizumab—for the prevention of acute rejection in renal transplantation

    Directory of Open Access Journals (Sweden)

    Junichiro Sageshima

    2009-06-01

    Full Text Available Junichiro Sageshima, Gaetano Ciancio, Linda Chen, George W Burke IIIDewitt Daughtry Family Department of Surgery, Division of Kidney and Pancreas Transplantation, The Lillian Jean Kaplan Renal Transplant Center, University of Miami Leonard M. Miller School of Medicine, Miami, FL, USAAbstract: The use of antibody induction after kidney transplantation has increased from 25% to 63% in the past decade and roughly one half of the induction agent used is anti-interleukin-2 receptor antibody (IL-2RA, ie, basiliximab or daclizumab. When combined with calcineurin inhibitor (CNI-based immunosuppression, IL-2RAs have been shown to reduce the incidence of acute rejection, one of the predictors of poor graft survival, without increasing risks of infections and malignancies in kidney transplantation. For low-immunological-risk patients, IL-2RAs, as compared with lymphocyte-depleting antibodies, are equally efficacious and have better safety profiles. For high-risk patients, however, IL-2RAs may be inferior to lymphocyte-depleting antibodies for the prophylaxis of acute rejection. In an effort to reduce toxicities of other immunosuppressive medications without increasing the risk of acute rejection and chronic graft loss, IL-2RAs have often been combined with steroid- and CNI-sparing immunosuppression protocols. More data support the benefits of early steroid withdrawal with IL-2RA in low-risk patients, but preferred induction therapy for high-risk patients has yet to be determined. Although CNI-sparing protocols with IL-2RA may preserve renal function and improve long-term survival in selected patients, further studies are needed to identify those who benefit most from this strategy.Keywords: basiliximab, daclizumab, interleukin-2 receptor antagonist, kidney transplantation, monoclonal antibody

  16. Lipoprotein receptor LRP1 regulates leptin signaling and energy homeostasis in the adult central nervous system.

    Science.gov (United States)

    Liu, Qiang; Zhang, Juan; Zerbinatti, Celina; Zhan, Yan; Kolber, Benedict J; Herz, Joachim; Muglia, Louis J; Bu, Guojun

    2011-01-11

    Obesity is a growing epidemic characterized by excess fat storage in adipocytes. Although lipoprotein receptors play important roles in lipid uptake, their role in controlling food intake and obesity is not known. Here we show that the lipoprotein receptor LRP1 regulates leptin signaling and energy homeostasis. Conditional deletion of the Lrp1 gene in the brain resulted in an obese phenotype characterized by increased food intake, decreased energy consumption, and decreased leptin signaling. LRP1 directly binds to leptin and the leptin receptor complex and is required for leptin receptor phosphorylation and Stat3 activation. We further showed that deletion of the Lrp1 gene specifically in the hypothalamus by Cre lentivirus injection is sufficient to trigger accelerated weight gain. Together, our results demonstrate that the lipoprotein receptor LRP1, which is critical in lipid metabolism, also regulates food intake and energy homeostasis in the adult central nervous system.

  17. Identification of a novel antagonist of the ErbB1 receptor capable of inhibiting migration of human glioblastoma cells

    DEFF Research Database (Denmark)

    Staberg, Mikkel; Riemer, Christian; Xu, Ruodan

    2013-01-01

    B1 targeting peptide, termed Herfin-1, was designed based on a model of the tertiary structure of the EGF-EGFR ternary complex. The binding kinetics of this peptide were determined employing surface plasmon resonance analyses. ErbB1-4 expression and phosphorylation in human glioblastoma cell lines U...... processing. RESULTS: The present study shows that Herfin-1 functions as an ErbB1 antagonist. It binds to the extracellular domain of ErbB1 with a KD value of 361 nM. In U87 and U118 cells, both expressing high levels of ErbB1, Herfin-1 inhibits EGF-induced ErbB1 phosphorylation and cell migration....... Additionally, Herfin-1 was found to increase neurite outgrowth in cerebellar granule neurons, likely through the inhibition of a sustained weak ErbB1 activation. CONCLUSIONS: Targeting the ErbB1 receptor dimerization interface is a promising strategy to inhibit receptor activation in ErbB1-expressing glioma...

  18. Phosphorylation of histone H3 at threonine 11 establishes a novel chromatin mark for transcriptional regulation

    OpenAIRE

    Metzger, Eric; Yin, Na; Wissmann, Melanie; Kunowska, Natalia; Fischer, Kristin; Friedrichs, Nicolaus; Patnaik, Debasis; Higgins, Jonathan M.G.; Potier, Noelle; Scheidtmann, Karl-Heinz; Buettner, Reinhard; Schüle, Roland

    2007-01-01

    Posttranslational modifications of histones such as methylation, acetylation, and phosphorylation regulate chromatin structure and gene expression. Here we show that protein kinase C-related kinase 1 (PRK1) phosphorylates histone H3 at threonine 11 (H3T11) upon ligand-dependent recruitment to androgen receptor (AR) target genes. PRK1 is pivotal to AR function since PRK1 knockdown or inhibition impedes AR-dependent transcription. Blocking PRK1 function abrogates androgen-induced H3T11 phosphor...

  19. A Mass Spectrometry-Based Predictive Strategy Reveals ADAP1 is Phosphorylated at Tyrosine 364

    Energy Technology Data Exchange (ETDEWEB)

    Littrell, BobbiJo R [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2018-04-16

    The goal of this work was to identify phosphorylation sites within the amino acid sequence of human ADAP1. Using traditional mass spectrometry-based techniques we were unable to produce interpretable spectra demonstrating modification by phosphorylation. This prompted us to employ a strategy in which phosphorylated peptides were first predicted using peptide mapping followed by targeted MS/MS acquisition. ADAP1 was immunoprecipitated from extracts of HEK293 cells stably-transfected with ADAP1 cDNA. Immunoprecipitated ADAP1 was digested with proteolytic enzymes and analyzed by LC-MS in MS1 mode by high-resolution quadrupole time-of-flight mass spectrometry (QTOF-MS). Peptide molecular features were extracted using an untargeted data mining algorithm. Extracted peptide neutral masses were matched against the ADAP1 amino acid sequence with phosphorylation included as a predicted modification. Peptides with predicted phosphorylation sites were analyzed by targeted LC-MS2. Acquired MS2 spectra were then analyzed using database search engines to confirm phosphorylation. Spectra of phosphorylated peptides were validated by manual interpretation. Further confirmation was performed by manipulating phospho-peptide abundance using calf intestinal phosphatase (CIP) and the phorbol ester, phorbol 12-myristate 13-acetate (PMA). Of five predicted phosphopeptides, one, comprised of the sequence AVDRPMLPQEYAVEAHFK, was confirmed to be phosphorylated on a Tyrosine at position 364. Pre-treatment of cells with PMA prior to immunoprecipitation increased the ratio of phosphorylated to unphosphorylated peptide as determined by area counts of extracted ion chromatograms (EIC). Addition of CIP to immunoprecipitation reactions eliminated the phosphorylated form. A novel phosphorylation site was identified at Tyrosine 364. Phosphorylation at this site is increased by treatment with PMA. PMA promotes membrane translocation and activation of protein kinase C (PKC), indicating that Tyrosine 364

  20. Forsythoside A exerts antipyretic effect on yeast-induced pyrexia mice via inhibiting transient receptor potential vanilloid 1 function

    Science.gov (United States)

    Liu, Cuiling; Su, Hongchang; Wan, Hongye; Qin, Qingxia; Wu, Xuan; Kong, Xiangying; Lin, Na

    2017-01-01

    Transient receptor potential vanilloid 1 (TRPV1) is a non-selective cation channel gated by noxious heat, playing major roles in thermoregulation. Forsythoside A (FT-A) is the most abundant phenylethanoid glycosides in Fructus Forsythiae, which has been prescribed as a medicinal herb for treating fever in China for a long history. However, how FT-A affects pyrexia and what is the underlying molecular mechanism remain largely unknown. Here we found that FT-A exerted apparent antipyretic effect through decreasing the levels of prostaglandin E2 (PGE2) and interleukin 8 (IL-8) in a dose-dependent fashion on the yeast induced pyrexia mice. Interestingly, FT-A significantly downregulated TRPV1 expression in the hypothalamus and dorsal root ganglion (DRG) of the yeast induced pyrexia mice. Moreover, FT-A inhibited IL-8 and PGE2 secretions, and calcium influx in the HEK 293T-TRPV1 cells after stimulated with capsaicin, the specific TRPV1 agonist. Further investigation of the molecular mechanisms revealed that FT-A treatment rapidly inhibited phosphorylation of extracellular signal-regulated kinase (ERK), Jun N-terminal kinase (JNK) and p38 in both yeast induced pyrexia mice and HEK 293T-TRPV1 cells. These results suggest that FT-A may serve as a potential antipyretic agent and the therapeutic action of Fructus Forsythiae on pyretic related disease is, in part, due to the FT-A activities. PMID:28123347