Sample records for ck2 inhibitor dmat

  1. Selectivity analysis of protein kinase CK2 inhibitors DMAT, TBB and resorufin in cisplatin-induced stress responses

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    Fritz, Gerhard; Issinger, Olaf-Georg; Olsen, Birgitte Brinkmann


    by phosphorylation of JNK and H2AX). In the case of resorufin no interference with the stress-signaling pathway is observed, supporting the notion that TBB and DMAT interfere with upstream molecules involved in genotoxic stress signaling. We have also tested the protein kinase CK2 inhibitors with respect to cell......Targeting protein kinases as a therapeutic approach to treat various diseases, especially cancer is currently a fast growing business. Although many inhibitors are available, exhibiting remarkable potency, the major challenge is their selectivity. Here we show that the protein kinase CK2 inhibitors...

  2. Development of a high-throughput screening-compatible assay to identify inhibitors of the CK2alpha/CK2beta interaction

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    Hochscherf, Jennifer; Lindenblatt, Dirk; Steinkrueger, Michaela


    Increased activity of protein kinase CK2 is associated with various types of cancer, neurodegenerative diseases, and chronic inflammation. In the search for CK2 inhibitors, attention has expanded toward compounds disturbing the interaction between CK2alpha and CK2beta in addition to established...... active site-directed approaches. The current article describes the development of a fluorescence anisotropy-based assay that mimics the principle of CK2 subunit interaction by using CK2alpha1-335 and the fluorescent probe CF-Ahx-Pc as a CK2beta analog. In addition, we identified new inhibitors able...... to displace the fluorescent probe from the subunit interface on CK2alpha1-335. Both CF-Ahx-Pc and the inhibitors I-Pc and Cl-Pc were derived from the cyclic peptide Pc, a mimetic of the C-terminal CK2alpha-binding motif of CK2beta. The design of the two inhibitors was based on docking studies using the known...

  3. In Search of Small Molecule Inhibitors Targeting the Flexible CK2 Subunit Interface

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    Benoît Bestgen


    Full Text Available Protein kinase CK2 is a tetrameric holoenzyme composed of two catalytic (α and/or α’ subunits and two regulatory (β subunits. Crystallographic data paired with fluorescence imaging techniques have suggested that the formation of the CK2 holoenzyme complex within cells is a dynamic process. Although the monomeric CK2α subunit is endowed with a constitutive catalytic activity, many of the plethora of CK2 substrates are exclusively phosphorylated by the CK2 holoenzyme. This means that the spatial and high affinity interaction between CK2α and CK2β subunits is critically important and that its disruption may provide a powerful and selective way to block the phosphorylation of substrates requiring the presence of CK2β. In search of compounds inhibiting this critical protein–protein interaction, we previously designed an active cyclic peptide (Pc derived from the CK2β carboxy-terminal domain that can efficiently antagonize the CK2 subunit interaction. To understand the functional significance of this interaction, we generated cell-permeable versions of Pc, exploring its molecular mechanisms of action and the perturbations of the signaling pathways that it induces in intact cells. The identification of small molecules inhibitors of this critical interaction may represent the first-choice approach to manipulate CK2 in an unconventional way.

  4. The Development of CK2 Inhibitors: From Traditional Pharmacology to in Silico Rational Drug Design. (United States)

    Cozza, Giorgio


    Casein kinase II (CK2) is an ubiquitous and pleiotropic serine/threonine protein kinase able to phosphorylate hundreds of substrates. Being implicated in several human diseases, from neurodegeneration to cancer, the biological roles of CK2 have been intensively studied. Upregulation of CK2 has been shown to be critical to tumor progression, making this kinase an attractive target for cancer therapy. Several CK2 inhibitors have been developed so far, the first being discovered by "trial and error testing". In the last decade, the development of in silico rational drug design has prompted the discovery, de novo design and optimization of several CK2 inhibitors, active in the low nanomolar range. The screening of big chemical libraries and the optimization of hit compounds by Structure Based Drug Design (SBDD) provide telling examples of a fruitful application of rational drug design to the development of CK2 inhibitors. Ligand Based Drug Design (LBDD) models have been also applied to CK2 drug discovery, however they were mainly focused on methodology improvements rather than being critical for de novo design and optimization. This manuscript provides detailed description of in silico methodologies whose applications to the design and development of CK2 inhibitors proved successful and promising.

  5. Thermodynamics parameters for binding of halogenated benzotriazole inhibitors of human protein kinase CK2α. (United States)

    Winiewska, Maria; Kucińska, Katarzyna; Makowska, Małgorzata; Poznański, Jarosław; Shugar, David


    The interaction of human CK2α (hCK2α) with nine halogenated benzotriazoles, TBBt and its analogues representing all possible patterns of halogenation on the benzene ring of benzotriazole, was studied by biophysical methods. Thermal stability of protein-ligand complexes, monitored by calorimetric (DSC) and optical (DSF) methods, showed that the increase in the mid-point temperature for unfolding of protein-ligand complexes (i.e. potency of ligand binding to hCK2α) follow the inhibitory activities determined by biochemical assays. The dissociation constant for the ATP-hCK2α complex was estimated with the aid of microscale thermophoresis (MST) as 4.3±1.8 μM, and MST-derived dissociation constants determined for halogenated benzotriazoles, when converted according to known ATP concentrations, perfectly reconstruct IC50 values determined by the biochemical assays. Ligand-dependent quenching of tyrosine fluorescence, together with molecular modeling and DSC-derived heats of unfolding, support the hypothesis that halogenated benzotriazoles bind in at least two alternative orientations, and those that are efficient hCK2α inhibitors bind in the orientation which TBBt adopts in its complex with maize CK2α. DSC-derived apparent heat for ligand binding (ΔΔHbind) is driven by intermolecular electrostatic interactions between Lys68 and the triazole ring of the ligand, as indicated by a good correlation between ΔΔHbind and ligand pKa. Overall results, additionally supported by molecular modeling, confirm that a balance of hydrophobic and electrostatic interactions contribute predominantly (~40 kJ/mol), relative to possible intermolecular halogen/hydrogen bonding (less than 10 kJ/mol), in binding of halogenated benzotriazoles to the ATP-binding site of hCK2α. This article is part of a Special Issue entitled: Inhibitors of Protein Kinases. Copyright © 2015 Elsevier B.V. All rights reserved.

  6. Resorufin: a lead for a new protein kinase CK2 inhibitor

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    Sandholt, Iben Skjøth; Olsen, Birgitte Brinkmann; Guerra, Barbara


    Screening a natural compound library led to the identification of resorufin as a highly selective and potent inhibitor of protein kinase CK2. Out of 52 kinases tested, only CK2 was inhibited, in contrast to emodin, a structurally related, known CK2 inhibitor that, in addition to CK2, inhibited ten...... other kinases by 90%. The IC50 values determined for the CK2 holoenzymes were 1.5 mol/l and for the free catalytic subunits ca. 4 mol/l. Altogether four cell lines were subjected to resorufin and emodin treatment. In the case of the three prostate carcinoma cell lines (PC-3, DU-145, LNCaP), 24 h...... treatment with 40 mol/l resorufin led to 15-20% dead cells; however, no caspase-mediated apoptosis was observed. In the case of the colorectal carcinoma HCT116 cell line, a similar picture was obtained, yet, when resorufin was administered to cells treated with doxorubicin, apoptosis was strongly induced...

  7. Different Persistence of the Cellular Effects Promoted by Protein Kinase CK2 Inhibitors CX-4945 and TDB

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    Cristina Girardi


    Full Text Available We compare the cellular efficacy of two selective and cell permeable inhibitors of the antiapoptotic kinase CK2. One inhibitor, CX-4945, is already in clinical trials as antitumor drug, while the other, TDB, has been recently successfully employed to demonstrate the implication of CK2 in cellular (disregulation. We found that, upon treatment of cancer cells with these compounds, the extent of inhibition of endocellular CK2 is initially comparable but becomes significantly different after the inhibitors are removed from the cellular medium: while in CX-4945 treated cells CK2 activity is restored to control level after 24 h, in the case of TDB it is still strongly reduced after 4 days from removal. The biological effects of the two inhibitors have been analyzed by performing clonogenic, spheroid formation, and wound-healing assays: we observed a permanent inhibition of cell survival and migration in TDB-treated cells even after the inhibitor removal, while in the case of CX-4945 only its maintenance for the whole duration of the assay insured a persisting effect. We suggest that the superiority of TDB in maintaining kinase activity inhibited and perpetuating the consequent effects is an added value to be considered when planning new therapies based on CK2 targeting.

  8. Isomeric mono-, di-, and tri-bromobenzo-1H-triazoles as inhibitors of human protein kinase CK2α.

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    Romualda Wąsik

    Full Text Available To further clarify the role of the individual bromine atoms of 4,5,6,7-tetrabromotriazole (TBBt, a relatively selective inhibitor of protein kinase CK2, we have examined the inhibition (IC(50 of human CK2α by the two mono-, the four di-, and the two tri- bromobenzotriazoles relative to that of TBBt. Halogenation of the central vicinal C(5/C(6 atoms proved to be a key factor in enhancing inhibitory activity, in that 5,6-di-Br(2Bt and 4,5,6-Br(3Bt were almost as effective inhibitors as TBBt, notwithstanding their marked differences in pK(a for dissociation of the triazole proton. The decrease in pK(a on halogenation of the peripheral C(4/C(7 atoms virtually nullifies the gain due to hydrophobic interactions, and does not lead to a decrease in IC(50. Molecular modeling of structures of complexes of the ligands with the enzyme, as well as QSAR analysis, pointed to a balance of hydrophobic and electrostatic interactions as a discriminator of inhibitory activity. The role of halogen bonding remains debatable, as originally noted for the crystal structure of TBBt with CK2α (pdb1j91. Finally we direct attention to the promising applicability of our series of well-defined halogenated benzotriazoles to studies on inhibition of kinases other than CK2.

  9. Biochemical characterization of CK2alpha and alpha' paralogues and their derived holoenzymes: evidence for the existence of a heterotrimeric CK2alpha'-holoenzyme forming trimeric complexes

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    Olsen, Birgitte; Rasmussen, Tine; Niefind, Karsten


    cells, all others in Escherichia coli. IC(50) studies involving the established CK2 inhibitors DMAT, TBBt, TBBz, apigenin and emodin were carried out and the K(i) values calculated. Although the differences in the K(i) values found were modest, there was a general tendency showing that the CK2......'-derived holoenzyme lost ca. 90% of its activity after 14 min, whereas CK2alpha (2) (1-335) beta(2) only showed a loss of ca. 40% by this time of incubation. Gel filtration analyses were performed at high (500 mM) and low (150 mM) monovalent salt concentrations in the absence or presence of ATP. At 500 mM NaCl the CK...

  10. Synthesis, Biological Evaluation and Molecular Modeling of Substituted Indeno[1,2-b]indoles as Inhibitors of Human Protein Kinase CK2

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    Faten Alchab


    Full Text Available Due to their system of annulated 6-5-5-6-membered rings, indenoindoles have sparked great interest for the design of ATP-competitive inhibitors of human CK2. In the present study, we prepared twenty-one indeno[1,2-b]indole derivatives, all of which were tested in vitro on human CK2. The indenoindolones 5a and 5b inhibited human CK2 with an IC50 of 0.17 and 0.61 µM, respectively. The indeno[1,2-b]indoloquinone 7a also showed inhibitory activity on CK2 at a submicromolar range (IC50 = 0.43 µM. Additionally, a large number of indenoindole derivatives was evaluated for their cytotoxic activities against the cell lines 3T3, WI-38, HEK293T and MEF.

  11. A specific inhibitor of protein kinase CK2 delays gamma-H2Ax foci removal and reduces clonogenic survival of irradiated mammalian cells

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    Huber Peter E


    Full Text Available Abstract Background The protein kinase CK2 sustains multiple pro-survival functions in cellular DNA damage response and its level is tightly regulated in normal cells but elevated in cancers. Because CK2 is thus considered as potential therapeutic target, DNA double-strand break (DSB formation and rejoining, apoptosis induction and clonogenic survival was assessed in irradiated mammalian cells upon chemical inhibition of CK2. Methods MRC5 human fibroblasts and WIDR human colon carcinoma cells were incubated with highly specific CK2 inhibitor 4,5,6,7-tetrabromobenzotriazole (TBB, or mock-treated, 2 hours prior to irradiation. DSB was measured by pulsed-field electrophoresis (PFGE as well as gamma-H2AX foci formation and removal. Apoptosis induction was tested by DAPI staining and sub-G1 flow cytometry, survival was quantified by clonogenic assay. Results TBB treatment did not affect initial DNA fragmention (PFGE; up to 80 Gy or foci formation (1 Gy. While DNA fragment rejoining (PFGE was not inhibited by the drug, TBB clearly delayed gamma-H2AX foci disappearence during postirradiation incubation. No apoptosis induction could be detected for up to 38 hours for both cell lines and exposure conditions (monotherapies or combination, but TBB treatment at this moderately toxic concentration of 20 μM (about 40% survival enhanced radiation-induced cell killing in the clonogenic assay. Conclusions The data imply a role of CK2 in gamma-H2AX dephosporylation, most likely through its known ability to stimulate PP2A phosphatase, rather than DSB rejoining. The slight but definite clonogenic radiosensitization by TBB does apparently not result from interference with an apoptosis suppression function of CK2 in these cells but could reflect inhibitor-induced uncoupling of DNA damage response decay from break ligation.

  12. Protein Kinase CK2 Regulates Cytoskeletal Reorganization during Ionizing Radiation-Induced Senescence of Human Mesenchymal Stem Cells

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    Wang, Daojing; Jang, Deok-Jin


    Human mesenchymal stem cells (hMSC) are critical for tissue regeneration. How hMSC respond to genotoxic stresses and potentially contribute to aging and cancer remain underexplored. We demonstrated that ionizing radiation induced cellular senescence of hMSC over a period of 10 days, showing a critical transition between day 3 and day 6. This was confirmed by senescence-associated beta-galactosidase (SA-{beta}-gal) staining, protein expression profiles of key cell cycle regulators (retinoblastoma (Rb) protein, p53, p21{sup waf1/Cip1}, and p16{sup INK4A}), and senescence-associated secretory phenotypes (SASPs) (IL-8, IL-12, GRO, and MDC). We observed dramatic cytoskeletal reorganization of hMSC through reduction of myosin-10, redistribution of myosin-9, and secretion of profilin-1. Using a SILAC-based phosphoproteomics method, we detected significant reduction of myosin-9 phosphorylation at Ser1943, coinciding with its redistribution. Importantly, through treatment with cell permeable inhibitors (4,5,6,7-tetrabromo-1H-benzotriazole (TBB) and 2-dimethylamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT)), and gene knockdown using RNA interference, we identified CK2, a kinase responsible for myosin-9 phosphorylation at Ser1943, as a key factor contributing to the radiation-induced senescence of hMSC. We showed that individual knockdown of CK2 catalytic subunits CK2{alpha} and CK2{alpha}{prime} induced hMSC senescence. However, only knockdown of CK2{alpha} resulted in morphological phenotypes resembling those of radiation-induced senescence. These results suggest that CK2{alpha} and CK2{alpha}{prime} play differential roles in hMSC senescence progression, and their relative expression might represent a novel regulatory mechanism for CK2 activity.

  13. The CK2 alpha/CK2 beta interface of human protein kinase CK2 harbors a binding pocket for small molecules

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    Raaf, Jennifer; Brunstein, Elena; Issinger, Olaf-Georg


    . Inhibition kinetic studies corroborate the dual binding mode of the inhibitor. Structural comparisons reveal a surprising conformational plasticity of human CK2 alpha around both DRB binding sites. After local rearrangement, the allosteric site serves as a CK2 beta interface. This opens the potential......, selective CK2 inhibitors are required. An often-used CK2 inhibitor is 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole (DRB). In a complex structure with human CK2 alpha, DRB binds to the canonical ATP cleft, but additionally it occupies an allosteric site that can be alternatively filled by glycerol...

  14. The catalytic subunit of human protein kinase CK2 structurally deviates from its maize homologue in complex with the nucleotide competitive inhibitor emodin

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    Raaf, Jennifer; Klopffleisch, Karsten; Issinger, Olaf-Georg


    The Ser/Thr kinase CK2 (former name: casein kinase 2) is a heterotetrameric enzyme composed of two catalytic chains (CK2alpha) attached to a dimer of noncatalytic subunits. Together with the cyclin-dependent kinases and the mitogen-activated protein kinases, CK2alpha belongs to the CMGC family of...

  15. CK2: a protein kinase in need of control

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    Guerra, B; Boldyreff, B; Sarno, S


    Protein kinase CK2 is a heterotetrameric alpha2beta2 Ser/Thr protein kinase with some features unusual among the eukaryotic protein kinases: (1) CK2 recognizes phosphoacceptor sites specified by several acidic determinants; (2) CK2 can use both ATP and GTP as phosphoryl donors; and (3) the regula...... response to nucleotide analogs. The increasing knowledge of CK2 structure-function relationships will allow the design of highly selective inhibitors of this pleiotropic kinase with oncogenic potential....

  16. Structural Hypervariability of the Two Human Protein Kinase CK2 Catalytic Subunit Paralogs Revealed by Complex Structures with a Flavonol- and a Thieno[2,3-d]pyrimidine-Based Inhibitor

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    Karsten Niefind


    Full Text Available Protein kinase CK2 is associated with a number of human diseases, among them cancer, and is therefore a target for inhibitor development in industry and academia. Six crystal structures of either CK2α, the catalytic subunit of human protein kinase CK2, or its paralog CK2α′ in complex with two ATP-competitive inhibitors—based on either a flavonol or a thieno[2,3-d]pyrimidine framework—are presented. The structures show examples for extreme structural deformations of the ATP-binding loop and its neighbourhood and of the hinge/helix αD region, i.e., of two zones of the broader ATP site environment. Thus, they supplement our picture of the conformational space available for CK2α and CK2α′. Further, they document the potential of synthetic ligands to trap unusual conformations of the enzymes and allow to envision a new generation of inhibitors that stabilize such conformations.

  17. CK2 inhibitor CX-4945 blocks TGF-β1-induced epithelial-to-mesenchymal transition in A549 human lung adenocarcinoma cells.

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    Jiyeon Kim

    Full Text Available BACKGROUND: The epithelial-to-mesenchymal transition (EMT is a major phenotype of cancer metastasis and invasion. As a druggable cancer target, the inhibition of protein kinase CK2 (formally named to casein kinase 2 has been suggested as a promising therapeutic strategy to treat EMT-controlled cancer metastasis. This study aimed to evaluate the effect of the CK2 inhibitor CX-4945 on the processes of cancer migration and invasion during the EMT in A549 human lung adenocarcinoma cells. MATERIALS AND METHODS: The effect of CX-4945 on TGF-β1-induced EMT was evaluated in A549 cells treated with TGF-β1 (5 ng/ml and CX-4945. The effect of CX-4945 on TGF-β1-induced cadherin switch and activation of key signaling molecules involved in Smad, non-Smad, Wnt and focal adhesion signaling pathways were investigated by Western blot analysis, immunocytochemistry and reporter assay. Additionally, the effect of CX-4945 on TGF-β1-induced migration and invasion was investigated by wound healing assay, Boyden chamber assay, gelatin zymography, and the quantitative real-time PCR. RESULTS: CX-4945 inhibits the TGF-β1-induced cadherin switch and the activation of key signaling molecules involved in Smad (Smad2/3, Twist and Snail, non-Smad (Akt and Erk, Wnt (β-catenin and focal adhesion signaling pathways (FAK, Src and paxillin that cooperatively regulate the overall process of EMT. As a result, CX-4945 inhibits the migration and invasion of A549 cells accompanied with the downregulation of MMP-2 and 9. CONCLUSIONS: Clinical evaluation of CX-4945 in humans as a single agent in solid tumors and multiple myeloma has established its promising pharmacokinetic, pharmacodynamic, and safety profiles. Beyond regression of tumor mass, CX-4945 may be advanced as a new therapy for cancer metastasis and EMT-related disorders.

  18. Exploring the CK2 Paradox: Restless, Dangerous, Dispensable

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    Cinzia Franchin


    Full Text Available The history of protein kinase CK2 is crowded with paradoxes and unanticipated findings. Named after a protein (casein that is not among its physiological substrates, CK2 remained in search of its targets for more than two decades after its discovery in 1954, but it later came to be one of the most pleiotropic protein kinases. Being active in the absence of phosphorylation and/or specific stimuli, it looks unsuitable to participate in signaling cascades, but its “lateral” implication in a variety of signaling pathways is now soundly documented. At variance with many “onco-kinases”, CK2 is constitutively active, and no oncogenic CK2 mutant is known; still high CK2 activity correlates to neoplasia. Its pleiotropy and essential role may cast doubts on the actual “druggability” of CK2; however, a CK2 inhibitor is now in Phase II clinical trials for the treatment of cancer, and cell clones viable in the absence of CK2 are providing information about the mechanism by which cancer becomes addicted to high CK2 levels. A phosphoproteomics analysis of these CK2 null cells suggests that CK2 pleiotropy may be less pronounced than expected and supports the idea that the phosphoproteome generated by this kinase is flexible and not rigidly pre-determined.

  19. Safety and preliminary efficacy data of a novel Casein Kinase 2 (CK2 peptide inhibitor administered intralesionally at four dose levels in patients with cervical malignancies

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    Alonso Daniel F


    Full Text Available Abstract Background Cervical cancer is now considered the second leading cause of death among women worldwide, and its incidence has reached alarming levels, especially in developing countries. Similarly, high grade squamous intraepithelial lesion (HSIL, the precursor stage for cervical cancer, represents a growing health problem among younger women as the HSIL management regimes that have been developed are not fully effective. From the etiological point of view, the presence of Human Papillomavirus (HPV has been demonstrated to play a crucial role for developing cervical malignancies, and viral DNA has been detected in 99.7% of cervical tumors at the later stages. CIGB-300 is a novel cyclic synthetic peptide that induces apoptosis in malignant cells and elicits antitumor activity in cancer animal models. CIGB-300 impairs the Casein Kinase (CK2 phosphorylation, by targeting the substrate's phosphoaceptor domain. Based on the perspectives of CIGB-300 to treat cancer, this "first-in-human" study investigated its safety and tolerability in patients with cervical malignancies. Methods Thirty-one women with colposcopically and histologically diagnosed microinvasive or pre-invasive cervical cancer were enrolled in a dose escalating study. CIGB-300 was administered sequentially at 14, 70, 245 and 490 mg by intralesional injections during 5 consecutive days to groups of 7 – 10 patients. Toxicity was monitored daily until fifteen days after the end of treatment, when patients underwent conization. Digital colposcopy, histology, and HPV status were also evaluated. Results No maximum-tolerated dose or dose-limiting toxicity was achieved. The most frequent local events were pain, bleeding, hematoma and erythema at the injection site. The systemic adverse events were rash, facial edema, itching, hot flashes, and localized cramps. 75% of the patients experienced a significant lesion reduction at colposcopy and 19% exhibited full histological regression

  20. First inactive conformation of CK2 alpha, the catalytic subunit of protein kinase CK2

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    Raaf, Jennifer; Issinger, Olaf-Georg; Niefind, Karsten


    The Ser/Thr kinase casein kinase 2 (CK2) is a heterotetrameric enzyme composed of two catalytic chains (CK2alpha, catalytic subunit of CK2) attached to a dimer of two noncatalytic subunits (CK2beta, noncatalytic subunit of CK2). CK2alpha belongs to the superfamily of eukaryotic protein kinases...... and Tyr50, the space required by the triphospho moiety. We discuss some factors that may support or disfavor this inactive conformation, among them coordination of small molecules at a remote cavity at the CK2alpha/CK2beta interaction region and binding of a CK2beta dimer. The latter stabilizes...... of catalytic key elements. For CK2alpha, however, no strict physiological control of activity is known. Accordingly, CK2alpha was found so far exclusively in the characteristic conformation of active EPKs, which is, in this case, additionally stabilized by a unique intramolecular contact between the N...

  1. CK2 Secreted by Leishmania braziliensis Mediates Macrophage Association Invasion: A Comparative Study between Virulent and Avirulent Promastigotes

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    Ana Madeira Brito Zylbersztejn


    Full Text Available CK2 is a protein kinase distributed in different compartments of Leishmania braziliensis: an externally oriented ecto-CK2, an intracellular CK2, and a secreted CK2. This latter form is constitutively secreted from the parasite (CsCK2, but such secretion may be highly enhanced by the association of specific molecules, including enzyme substrates, which lead to a higher enzymatic activity, called inductively secreted CK2 (IsCK2. Here, we examined the influence of secreted CK2 (sCK2 activity on the infectivity of a virulent L. braziliensis strain. The virulent strain presented 121-fold higher total CK2 activity than those found in an avirulent strain. The use of specific CK2 inhibitors (TBB, DRB, or heparin inhibited virulent parasite growth, whereas no effect was observed in the avirulent parasites. When these inhibitors were added to the interaction assays between the virulent L. braziliensis strain and macrophages, association index was drastically inhibited. Polyamines enhanced sCK2 activity and increased the association index between parasites and macrophages. Finally, sCK2 and the supernatant of the virulent strain increased the association index between the avirulent strain and macrophages, which was inhibited by TBB. Thus, the kinase enzyme CK2 seems to be important to invasion mechanisms of L. braziliensis.

  2. Interaction between CK2α and CK2β, the subunits of protein kinase CK2: thermodynamic contributions of key residues on the CK2α surface

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    Raaf, Jennifer; Bischoff, Nils; Klopffleisch, Karsten


    The protein Ser/Thr kinase CK2 (former name: casein kinase II) exists predominantly as a heterotetrameric holoenzyme composed of two catalytic subunits (CK2α) bound to a dimer of noncatalytic subunits (CK2β). We undertook a study to further understand how these subunits interact to form...... the tetramer. To this end, we used recombinant, C-terminal truncated forms of human CK2 subunits that are able to form the holoenzyme. We analyzed the interaction thermodynamics between the binding of CK2α and CK2β as well as the impact of changes in temperature, pH, and the ionization enthalpy of the buffer...... using isothermal titration calorimetry (ITC). With structure-guided alanine scanning mutagenesis we truncated individual side chains in the hydrophobic amino acid cluster located within the CK2α interface to identify experimentally the amino acids that dominate affinity. The ITC results indicate...

  3. Low-density crystal packing of human protein kinase CK2 catalytic subunit in complex with resorufin or other ligands

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    Klopffleisch, Karsten; Niefind, Karsten; Issinger, Olaf-Georg


    A low-resolution structure of the catalytic subunit CK2α of human protein kinase CK2 (formerly known as casein kinase 2) in complex with the ATP-competitive inhibitor resorufin is presented. The structure supplements previous human CK2α structures in which the interdomain hinge/helix αD region...

  4. Primary and secondary interactions between CK2alpha and CK2beta lead to ring-like structures in the crystals of the CK2 holoenzyme

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    Niefind, Karsten; Issinger, Olaf-Georg


    Protein kinase CK2 predominantly exists as a heterotetrameric holoenyzme consisting of two catalytic subunits (CK2alpha) and two non-catalytic subunits (CK2beta). Early investigations which we review here had revealed the presence of two types of contacts between CK2alpha and CK2beta: a primary...... interaction responsible for the stability of the CK2 holoenzyme and stimulatory for the catalytic activity, and a secondary interaction which is inhibitory and in which the acidic loop of CK2beta associates with the basic stretch and the (p+1)-loop of CK2alpha. At the end of the last decade both types...... a distinct aggregation propensity of CK2. We demonstrate here that in the CK2 holoenzyme crystals contacts between different CK2 tetramers exists which provide structural details of the secondary CK2alpha/CK2beta interactions. These mainly ionic interactions lead to trimeric rings of CK2 holoenzymes...

  5. Protein kinase CK2 in health and disease: Protein kinase CK2: from structures to insights

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    Niefind, K; Raaf, J; Issinger, Olaf-Georg


    Within the last decade, 40 crystal structures corresponding to protein kinase CK2 (former name 'casein kinase 2'), to its catalytic subunit CK2alpha and to its regulatory subunit CK2beta were published. Together they provide a valuable, yet by far not complete basis to rationalize the biochemical...... the critical region of CK2alpha recruitment is pre-formed in the unbound state. In CK2alpha the activation segment - a key element of protein kinase regulation - adapts invariably the typical conformation of the active enzymes. Recent structures of human CK2alpha revealed a surprising plasticity in the ATP...

  6. Structure of the Human Protein Kinase CK2 Catalytic Subunit CK2α′ and Interaction Thermodynamics with the Regulatory Subunit CK2β

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    Bischoff, Nils; Olsen, Birgitte Brinkmann; Raaf, Jennifer


    Protein kinase CK2 (formerly "casein kinase 2") is composed of a central dimer of noncatalytic subunits (CK2β) binding two catalytic subunits. In humans, there are two isoforms of the catalytic subunit (and an additional splicing variant), one of which (CK2α) is well characterized. To supplement...... of CK2α' for CK2β is about 12 times lower than that of CK2α and is less driven by enthalpy. This result fits the observation that the β4/β5 loop, a key element of the CK2α/CK2β interface, adopts an open conformation in CK2α', while in CK2α, it opens only after assembly with CK2β. The open β4/β5 loop...

  7. Conformational plasticity of the catalytic subunit of protein kinase CK2 and its consequences for regulation and drug design

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    Niefind, Karsten; Issinger, Olaf-Georg


    well to the constitutive activity of the enzyme, meaning, its independence from phosphorylation or other characteristic control factors. Most CK2alpha structures are based on the enzyme from Zea mays, supplemented by an increasing number of human CK2alpha structures. In the latter a surprising...... molecule seems to favour the partially and fully inactive states. This observation may be exploited to design effective and selective CK2 inhibitors....

  8. A subnanomolar fluorescent probe for protein kinase CK2 interaction studies

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    Enkvist, Erki; Viht, Kaido; Bischoff, Nils


    assay that used thin layer chromatography for the measurement of the rate of phosphorylation of fluorescently labelled peptide 5-TAMRA-RADDSDDDDD. The most potent inhibitor, ARC-1502 (K(i) = 0.5 nM), revealed high selectivity for CK2α in a panel of 140 protein kinases. Labelling of ARC-1502 with Promo......Up-regulation of an acidophilic protein kinase, CK2, has been established in several types of cancer. This cognition has made CK2 an important target for drug development for cancer chemotherapy. The characterization of potential drug candidates, determination of the structure and clarification...

  9. Cancer-type dependent expression of CK2 transcripts.

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    Melissa M J Chua

    Full Text Available A multitude of proteins are aberrantly expressed in cancer cells, including the oncogenic serine-threonine kinase CK2. In a previous report, we found increases in CK2 transcript expression that could explain the increased CK2 protein levels found in tumors from lung and bronchus, prostate, breast, colon and rectum, ovarian and pancreatic cancers. We also found that, contrary to the current notions about CK2, some CK2 transcripts were downregulated in several cancers. Here, we investigate all other cancers using Oncomine to determine whether they also display significant CK2 transcript dysregulation. As anticipated from our previous analysis, we found cancers with all CK2 transcripts upregulated (e.g. cervical, and cancers where there was a combination of upregulation and/or downregulation of the CK2 transcripts (e.g. sarcoma. Unexpectedly, we found some cancers with significant downregulation of all CK2 transcripts (e.g. testicular cancer. We also found that, in some cases, CK2 transcript levels were already dysregulated in benign lesions (e.g. Barrett's esophagus. We also found that CK2 transcript upregulation correlated with lower patient survival in most cases where data was significant. However, there were two cancer types, glioblastoma and renal cell carcinoma, where CK2 transcript upregulation correlated with higher survival. Overall, these data show that the expression levels of CK2 genes is highly variable in cancers and can lead to different patient outcomes.

  10. Interaction of tubulin and protein kinase CK2 in Trypanosoma equiperdum. (United States)

    Boscán, Beatriz E; Uzcanga, Graciela L; Calabokis, Maritza; Camargo, Rocío; Aponte, Frank; Bubis, José


    A polypeptide band with an apparent molecular weight of 55,000 was phosphorylated in vitro in whole-cell lysates of Trypanosoma equiperdum. This band corresponds to tubulin as demonstrated by immunoprecipitation of the phosphorylated polypeptide from T. equiperdum extracts when anti-α and anti-β tubulin monoclonal antibodies were employed. A parasite protein kinase CK2 was in charge of modifying tubulin given that common mammalian CK2 inhibitors such as emodin and GTP, hindered the phosphorylation of tubulin and exogenously added casein. Interestingly, a divalent cation-dependent translocation of the T. equiperdum tubulin and the CK2 responsible for its phosphorylation was noticed, suggesting a direct interaction between these two proteins. Additionally, this fraction of tubulin and its kinase coeluted using separations based on parameters as different as charge (DEAE-Sepharose anion-exchange chromatography) and size (Sephacryl S-300 gel filtration chromatography). Analyses by non-denaturing polyacrylamide gel electrophoresis and immunoblot of the purified and radioactively labeled fraction containing both tubulin and the CK2 enzyme, established the phosphorylation of a single band that was recognized by anti-CK2 α-subunit and anti-tubulin antibodies. All these findings revealed a physical association between a pool of tubulin and a CK2 in T. equiperdum.

  11. Protein kinase CK2 in human diseases

    DEFF Research Database (Denmark)

    Guerra, Barbara; Issinger, Olaf-Georg


    ) it is found elevated in most tumors investigated and rapidly proliferating tissues. With the elucidation of the structure of the catalytic subunit, it was possible to explain why the enzyme is constitutively active [1] and why it can bind GTP [2]. Considerable information on the potential roles of CK2...... in various disease processes including cancer has been gained in recent years, and the present review may help to further elucidate its aberrant role in many disease states. Its peculiar structural features [3-9] may be advantageous in designing tailor-made compounds with the possibility to specifically...

  12. Protein kinase CK2 modulates IL-6 expression in inflammatory breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Drygin, Denis, E-mail:; Ho, Caroline B.; Omori, Mayuko; Bliesath, Joshua; Proffitt, Chris; Rice, Rachel; Siddiqui-Jain, Adam; O' Brien, Sean; Padgett, Claire; Lim, John K.C.; Anderes, Kenna; Rice, William G.; Ryckman, David


    Highlights: Black-Right-Pointing-Pointer We examine the potential cross-talk between CK2 and IL-6. Black-Right-Pointing-Pointer Inhibition of CK2 by siRNA or CX-4945 inhibits expression of IL-6 in models of IBC. Black-Right-Pointing-Pointer Treatment of IBC patient in the clinic with CX-4945 reduces her IL-6 plasma levels. Black-Right-Pointing-Pointer We demonstrate that CK2 is a potential therapeutic target for IL-6 driven diseases. -- Abstract: Inflammatory breast cancer is driven by pro-angiogenic and pro-inflammatory cytokines. One of them Interleukin-6 (IL-6) is implicated in cancer cell proliferation and survival, and promotes angiogenesis, inflammation and metastasis. While IL-6 has been shown to be upregulated by several oncogenes, the mechanism behind this phenomenon is not well characterized. Here we demonstrate that the pleotropic Serine/Threonine kinase CK2 is implicated in the regulation of IL-6 expression in a model of inflammatory breast cancer. We used siRNAs targeted toward CK2 and a selective small molecule inhibitor of CK2, CX-4945, to inhibit the expression and thus suppress the secretion of IL-6 in in vitro as well as in vivo models. Moreover, we report that in a clinical trial, CX-4945 was able to dramatically reduce IL-6 levels in plasma of an inflammatory breast cancer patient. Our data shed a new light on the regulation of IL-6 expression and position CX-4945 and potentially other inhibitors of CK2, for the treatment of IL-6-driven cancers and possibly other diseases where IL-6 is instrumental, including rheumatoid arthritis.

  13. Protein kinase CK2: evidence for a protein kinase CK2beta subunit fraction, devoid of the catalytic CK2alpha subunit, in mouse brain and testicles

    DEFF Research Database (Denmark)

    Guerra, B; Siemer, S; Boldyreff, B


    The highest CK2 activity was found in mouse testicles and brain, followed by spleen, liver, lung, kidney and heart. The activity values were directly correlated with the protein expression level of the CK2 subunits alpha (catalytic) and beta (regulatory). The alpha' subunit was only detected...... signals were observed for lung, liver and testicles. In the case of CK2beta mRNA the highest signals were found for testicles, kidney, brain and liver. The amount of CK2beta mRNA in testicles was estimated to be about 6-fold higher than in brain. The strongest CK2beta signals in the Western blot were...... found for testicles and brain. The amount of CK2beta protein in brain in comparison to the other organs (except testicles) was estimated to be ca. 2-3-fold higher whereas the ratio of CK2beta between testicles and brain was estimated to be 3-4-fold. Results from the immunoprecipitation experiments...

  14. CK2 Phosphorylates and Inhibits TAp73 Tumor Suppressor Function to Promote Expression of Cancer Stem Cell Genes and Phenotype in Head and Neck Cancer

    Directory of Open Access Journals (Sweden)

    Hai Lu


    Full Text Available Cancer stem cells (CSC and genes have been linked to cancer development and therapeutic resistance, but the signaling mechanisms regulating CSC genes and phenotype are incompletely understood. CK2 has emerged as a key signal serine/threonine kinase that modulates diverse signal cascades regulating cell fate and growth. We previously showed that CK2 is often aberrantly expressed and activated in head and neck squamous cell carcinomas (HNSCC, concomitantly with mutant (mt tumor suppressor TP53, and inactivation of its family member, TAp73. Unexpectedly, we observed that classical stem cell genes Nanog, Sox2, and Oct4, are overexpressed in HNSCC with inactivated TAp73 and mtTP53. However, the potential relationship between CK2, TAp73 inactivation, and CSC phenotype is unknown. We reveal that inhibition of CK2 by pharmacologic inhibitors or siRNA inhibits the expression of CSC genes and side population (SP, while enhancing TAp73 mRNA and protein expression. Conversely, CK2 inhibitor attenuation of CSC protein expression and the SP by was abrogated by TAp73 siRNA. Bioinformatic analysis uncovered a single predicted CK2 threonine phosphorylation site (T27 within the N-terminal transactivation domain of TAp73. Nuclear CK2 and TAp73 interaction, confirmed by co-immunoprecipitation, was attenuated by CK2 inhibitor, or a T27A point-mutation of this predicted CK2 threonine phospho-acceptor site of TAp73. Further, T27A mutation attenuated phosphorylation, while enhancing TAp73 function in repressing CSC gene expression and SP cells. A new CK2 inhibitor, CX-4945, inhibited CSC related SP cells, clonogenic survival, and spheroid formation. Our study unveils a novel regulatory mechanism whereby aberrant CK2 signaling inhibits TAp73 to promote the expression of CSC genes and phenotype.

  15. Protein kinase CK2 structure-function relationship

    DEFF Research Database (Denmark)

    Boldyreff, B; Meggio, F; Pinna, L A


    Protein kinase CK2 subunits alpha and beta were expressed either separately or together in a bacterial expression system (pT7-7/BL21(DE3)) and purified to homogeneity. After mixing the subunits, a CK2 holoenzyme (alpha 2 beta 2) was spontaneously reconstituted, which displays identical features a...

  16. Stress-induced activation of protein kinase CK2 by direct interaction with p38 mitogen-activated protein kinase

    DEFF Research Database (Denmark)

    Sayed, M; Kim, S O; Salh, B S


    in the human cervical carcinoma HeLa cells by up to 8-fold, and this could be blocked by the p38 MAP kinase inhibitor SB203580. We show that p38alpha MAP kinase, in a phosphorylation-dependent manner, can directly interact with the alpha and beta subunits of CK2 to activate the holoenzyme through what appears......Protein kinase CK2 has been implicated in the regulation of a wide range of proteins that are important in cell proliferation and differentiation. Here we demonstrate that the stress signaling agents anisomycin, arsenite, and tumor necrosis factor-alpha stimulate the specific enzyme activity of CK2...... to be an allosteric mechanism. Furthermore, we demonstrate that anisomycin- and tumor necrosis factor-alpha-induced phosphorylation of p53 at Ser-392, which is important for the transcriptional activity of this growth suppressor protein, requires p38 MAP kinase and CK2 activities....

  17. Crystal structure of human protein kinase CK2: insights into basic properties of the CK2 holoenzyme

    DEFF Research Database (Denmark)

    Niefind, K; Guerra, B; Ermakowa, I


    The crystal structure of a fully active form of human protein kinase CK2 (casein kinase 2) consisting of two C-terminally truncated catalytic and two regulatory subunits has been determined at 3.1 A resolution. In the CK2 complex the regulatory subunits form a stable dimer linking the two catalyt...

  18. Stimulation of Leishmania tropica protein kinase CK2 activities by platelet-activating factor (PAF). (United States)

    Dutra, Patricia M L; Vieira, Danielle P; Meyer-Fernandes, Jose R; Silva-Neto, Mario A C; Lopes, Angela H


    Leishmania tropica is one of the causative agents of cutaneous leishmaniasis. Platelet-activating factor (PAF) is a phospholipid mediator in diverse biological and pathophysiological processes. Here we show that PAF promoted a three-fold increase on ecto-protein kinase and a three-fold increase on the secreted kinase activity of L. tropica live promastigotes. When casein was added to the reaction medium, along with PAF, there was a four-fold increase on the ecto-kinase activity. When live L. tropica promastigotes were pre-incubated for 30 min in the presence of PAF-plus casein, a six-fold increase on the secreted kinase activity was observed. Also, a protein released from L. tropica promastigotes reacted with polyclonal antibodies for the mammalian CK2 alpha catalytic subunit. Furthermore, in vitro mouse macrophage infection by L. tropica was doubled when promastigotes were pre-treated for 2 h with PAF. Similar results were obtained when the interaction was performed in the presence of purified CK2 or casein. TBB and DRB, CK2 inhibitors, reversed PAF enhancement of macrophage infection by L. tropica. WEB 2086, a competitive PAF antagonist, reversed all PAF effects here described. This study shows for the first time that PAF promotes the activation of two isoforms of CK2, secreted and membrane-bound, correlating these activities to infection of mouse macrophages.

  19. Targeting CK2-driven non-oncogene addiction in B-cell tumors. (United States)

    Mandato, E; Manni, S; Zaffino, F; Semenzato, G; Piazza, F


    Genetic mutations of oncogenes often underlie deranged cell growth and altered differentiation pathways leading to malignant transformation of B-lymphocytes. However, addiction to oncogenes is not the only drive to lymphoid tumor pathogenesis. Dependence on non-oncogenes, which act by propelling basic mechanisms of cell proliferation and survival, has also been recognized in the pathobiology of lymphoid leukemias, lymphomas and multiple myeloma. Among the growing number of molecules that may uphold non-oncogene addiction, a key place is increasingly being recognized to the serine-threonine kinase CK2. This enzyme is overexpressed and overactive in B-acute lymphoblastic leukemia, multiple myeloma, chronic lymphocytic leukemia and non-Hodgkin lymphomas, such as mantle cell, follicular, Burkitt's and diffuse large B-cell lymphomas. In these tumors, CK2 may serve the activity of oncogenes, similar to BCR-ABL and c-MYC, control the activation of critical signaling cascades, such as NF-κB (nuclear factor-κB), STAT3 (signal transducer and activator of transcription 3) and PTEN/PI3K/AKT (phosphatase and tensin homolog protein/phosphoinositide 3-kinase/AKR thymoma), and sustain multiple cellular stress-elicited pathways, such as the proteotoxic stress, unfolded protein and DNA-damage responses. CK2 has also been shown to have an essential role in tuning signals derived from the stromal tumor microenvironment. Not surprisingly, targeting CK2 in lymphoid tumor cell lines or mouse xenograft models can boost the cytotoxic effects of both conventional chemotherapeutics and novel agents, similar to heat-shock protein 90, proteasome and tyrosine kinases inhibitors. In this review, we summarize the evidence indicating how CK2 embodies most of the features of a cancer growth-promoting non-oncogene, focusing on lymphoid tumors. We further discuss the preclinical data of the use of small ATP-competitive CK2 inhibitors, which hold the promise to be additional options in novel drug

  20. Targeting Protein Kinase CK2: Evaluating CX-4945 Potential for GL261 Glioblastoma Therapy in Immunocompetent Mice (United States)

    Ferrer-Font, Laura; Villamañan, Lucia; Arias-Ramos, Nuria; Vilardell, Jordi; Plana, Maria; Ruzzene, Maria; Pinna, Lorenzo A.; Itarte, Emilio; Arús, Carles; Candiota, Ana Paula


    Glioblastoma (GBM) causes poor survival in patients even with aggressive treatment. Temozolomide (TMZ) is the standard chemotherapeutic choice for GBM treatment but resistance always ensues. Protein kinase CK2 (CK2) contributes to tumour development and proliferation in cancer, and it is overexpressed in human GBM. Accordingly, targeting CK2 in GBM may benefit patients. Our goal has been to evaluate whether CK2 inhibitors (iCK2s) could increase survival in an immunocompetent preclinical GBM model. Cultured GL261 cells were treated with different iCK2s including CX-4945, and target effects evaluated in vitro. CX-4945 was found to decrease CK2 activity and Akt(S129) phosphorylation in GL261 cells. Longitudinal in vivo studies with CX-4945 alone or in combination with TMZ were performed in tumour-bearing mice. Increase in survival (p < 0.05) was found with combined CX-4945 and TMZ metronomic treatment (54.7 ± 11.9 days, n = 6) when compared to individual metronomic treatments (CX-4945: 24.5 ± 2.0 and TMZ: 38.7 ± 2.7, n = 6) and controls (22.5 ± 1.2, n = 6). Despite this, CX-4945 did not improve mice outcome when administered on every/alternate days, either alone or in combination with 3-cycle TMZ. The highest survival rate was obtained with the metronomic combined TMZ+CX-4945 every 6 days, pointing to the participation of the immune system or other ancillary mechanism in therapy response. PMID:28208677

  1. Targeting Protein Kinase CK2: Evaluating CX-4945 Potential for GL261 Glioblastoma Therapy in Immunocompetent Mice

    Directory of Open Access Journals (Sweden)

    Laura Ferrer-Font


    Full Text Available Glioblastoma (GBM causes poor survival in patients even with aggressive treatment. Temozolomide (TMZ is the standard chemotherapeutic choice for GBM treatment but resistance always ensues. Protein kinase CK2 (CK2 contributes to tumour development and proliferation in cancer, and it is overexpressed in human GBM. Accordingly, targeting CK2 in GBM may benefit patients. Our goal has been to evaluate whether CK2 inhibitors (iCK2s could increase survival in an immunocompetent preclinical GBM model. Cultured GL261 cells were treated with different iCK2s including CX-4945, and target effects evaluated in vitro. CX-4945 was found to decrease CK2 activity and Akt(S129 phosphorylation in GL261 cells. Longitudinal in vivo studies with CX-4945 alone or in combination with TMZ were performed in tumour-bearing mice. Increase in survival (p < 0.05 was found with combined CX-4945 and TMZ metronomic treatment (54.7 ± 11.9 days, n = 6 when compared to individual metronomic treatments (CX-4945: 24.5 ± 2.0 and TMZ: 38.7 ± 2.7, n = 6 and controls (22.5 ± 1.2, n = 6. Despite this, CX-4945 did not improve mice outcome when administered on every/alternate days, either alone or in combination with 3-cycle TMZ. The highest survival rate was obtained with the metronomic combined TMZ+CX-4945 every 6 days, pointing to the participation of the immune system or other ancillary mechanism in therapy response.

  2. Protein kinase CK2 inhibition is associated with the destabilization of HIF-1α in human cancer cells

    DEFF Research Database (Denmark)

    Guerra, Barbara; Rasmussen, Tine D. L.; Schnitzler, Alexander


    Screening for protein kinase CK2 inhibitors of the structural diversity compound library (DTP NCI/NIH) led to the discovery of 4-[(E)-(fluoren-9-ylidenehydrazinylidene)-methyl]benzoic acid (E9). E9 induces apoptotic cell death in various cancer cell lines and upon hypoxia, the compound suppresses...

  3. CIGB-300, an anti-CK2 peptide, inhibits angiogenesis, tumor cell invasion and metastasis in lung cancer models. (United States)

    Benavent Acero, Fernando; Capobianco, Carla S; Garona, Juan; Cirigliano, Stéfano M; Perera, Yasser; Urtreger, Alejandro J; Perea, Silvio E; Alonso, Daniel F; Farina, Hernan G


    Casein kinase 2 (CK2) is overexpressed in several types of cancer. It has more than 300 substrates mainly involved in DNA reparation and replication, chromatin remodeling and cellular growth. In recent years CK2 became an interesting target for anticancer drug development. CIGB-300 is a peptidic inhibitor of CK2 activity, designed to bind to the phospho-acceptor domain of CK2 substrates, impairing the correct phosphorylation by the enzyme. The aim of this work was to explore the antitumor effects of this inhibitor in preclinical lung cancer models. Human H125 and murine 3LL Lewis lung carcinoma cell lines were used to evaluate the effect of CIGB-300 treatment in vitro. For this purpose, adhesion, migration and invasion capabilities of cancer cells were tested. Proteolytic activity of tumor cell-secreted uPA and MMP after CIGB-300 incubation was also analyzed. In vivo anticancer efficacy of the peptide was evaluated using experimental and spontaneous lung colonization assays in C57BL/6 mice. Finally, in order to test the effect of CIGB-300 on tumor cell-induced angiogenesis, a modified Matrigel plug assay was conducted. We demonstrate that treatment with low micromolar concentrations of CIGB-300 caused a drastic reduction of adhesion, migration and invasion of lung cancer cells. Reduced invasiveness after CIGB-300 incubation was associated with decreased proteolytic activity of tumor cell-conditioned medium. In vivo, intravenous administration of CIGB-300 (10mg/kg) markly decreased lung colonization and metastasis development of 3LL cells. Interestingly, after 5days of systemic treatment with CIGB-300, tumor cell-driven neovascularization was significantly reduced in comparison to control group. Altogether our data suggest an important role of CK2 in lung tumor development, suggesting a potential use of CIGB-300 as a novel therapeutic agent against lung cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  4. Exploring the Pivotal Role of the CK2 Hinge Region Sub-Pocket in Binding with Tricyclic Quinolone Analogues by Computational Analysis

    Directory of Open Access Journals (Sweden)

    Yue Zhou


    Full Text Available Protein kinase CK2 has been considered as an attractive therapeutic target of cancer therapy. The tricyclic quinoline compound CX-4945 is the first representative of CK2 inhibitors used in human clinical trials. The binding of non-2,6-naphtyridine substituted compounds 27e (IC50 > 500 nM and 27h (IC50 > 1000 nM to CK2 is abolished. However, the unbinding mechanisms due to the key pharmacophore group replacement of compounds 27e and 27h are unveiled. In the present work, combined computational analysis was performed to investigate the underlying structural basis of the low-affinity of two systems. As indicated in the results, the loss of hydrogen bonds between the non-2,6-naphtyridine and the hinge region destroyed the proper recognition of the two complexes. Besides, the allosteric mechanisms between the deviated ligands and the changed regions (G-loop, C-loop and β4/β5 loop are proposed. Furthermore, energetic analysis was evaluated by detailed energy calculation and residue-based energy decomposition. More importantly, the summary of known polar pharmacophore groups elucidates the pivotal roles of hinge region sub-pocket in the binding of CK2 inhibitors. These results provide rational clues to the fragment-based design of more potent CK2 inhibitors.

  5. Evaluation of protein kinase CK2 as a therapeutic target for squamous cell carcinoma of cats. (United States)

    Cannon, Claire M; Trembley, Janeen H; Kren, Betsy T; Unger, Gretchen M; O'Sullivan, M Gerard; Cornax, Ingrid; Modiano, Jaime F; Ahmed, Khalil


    OBJECTIVE To investigate protein kinase CK2 (CK2) expression in squamous cell carcinoma (SCC) of cats and to examine effects of CK2 downregulation on in vitro apoptosis and viability in SCC. SAMPLE Biopsy specimens of oral mucosa and testis and blood samples from clinically normal cats, biopsy specimens of oral SCC from cats, and feline SCC (SCCF1) and mammary gland carcinoma (K12) cell lines. PROCEDURES Immunohistochemical labeling for CK2α was performed on biopsy specimens. Sequences of the CK2α subunit gene and CK2α' subunit gene in feline blood and feline cancer cell lines were determined by use of PCR and reverse-transcription PCR assays followed by direct Sanger sequencing. Specific small interfering RNAs (siRNAs) were developed for feline CK2α and CK2α'. The SCCF1 cells were treated with siRNA and assessed 72 hours later for CK2α and CK2α' expression and markers of apoptosis (via western blot analysis) and for viability (via 3-[4,5-dimethylthiazol-2-yl]-5-[3-carboxymethoxyphenyl]-2-[4-sulfophenyl]-2H-tetrazolium assays). RESULTS CK2α was expressed in all feline oral mucosa samples and 7 of 8 oral SCC samples. Expression of CK2α and CK2α' was successfully downregulated in SCCF1 cells by use of siRNAs, which resulted in decreased viability and induction of apoptosis. CONCLUSIONS AND CLINICAL RELEVANCE In this study, CK2 appeared to be a promising therapeutic target for SCCs of cats. A possible treatment strategy for SCCs of cats would be RNA interference that targets CK2.

  6. Human herpesvirus 6B induces phosphorylation of p53 in its regulatory domain by a CK2- and p38-independent pathway

    DEFF Research Database (Denmark)

    Øster, Bodil; Bundgaard, Bettina; Hupp, TR


    Here, we demonstrate that human herpesvirus 6B (HHV-6B) infection upregulates the tumour suppressor p53 and induces phosphorylation of p53 at Ser392. Interestingly, phosphorylation at the equivalent site has previously been shown to correlate with p53 tumour suppression in murine models. Although......, eluted in column fractions that phosphorylated p53 at Ser392. However, treatment of cells with neither the CK2 and Cdk9 inhibitor 5,6-dichloro-1-beta-d-ribofuranosylbenzimidazole (DRB) nor p38 kinase inhibitors reduced HHV-6B-induced Ser392 phosphorylation significantly. Knockdown of the CK2beta subunit...... or p38alpha by small interfering RNA had no effect on HHV-6B-induced phosphorylation of p53 at Ser392. Thus, HHV-6B induces p53 Ser392 phosphorylation by an atypical pathway independent of CK2 and p38 kinases, whereas mitogen-activated protein (MAP) kinase signalling pathways are involved in viral...

  7. Protein Kinase CK2: A Targetable BCR-ABL Partner in Philadelphia Positive Leukemias

    Directory of Open Access Journals (Sweden)

    Alessandro Morotti


    Full Text Available BCR-ABL-mediated leukemias, either Chronic Myeloid Leukemia (CML or Philadelphia positive Acute Lymphoblastic Leukemia (ALL, are the paradigm of targeted molecular therapy of cancer due to the impressive clinical responses obtained with BCR-ABL specific tyrosine kinase inhibitors (TKIs. However, BCR-ABL TKIs do not allow completely eradicating both CML and ALL. Furthermore, ALL therapy is associated with much worse responses to TKIs than those observed in CML. The identification of additional pathways that mediate BCR-ABL leukemogenesis is indeed mandatory to achieve synthetic lethality together with TKI. Here, we review the role of BCR-ABL/protein kinase CK2 interaction in BCR-ABL leukemias, with potentially relevant implications for therapy.

  8. Macro CK2 accumulation in tenofovir-treated HIV patients is facilitated by CK oligomer stabilization but is not predictive for pathology. (United States)

    Schmid, Holger; Tokarska-Schlattner, Malgorzata; Füeßl, Birgit; Röder, Maximilian; Kay, Laurence; Attia, Stéphane; Lederer, Stephan R; Goebel, Frank D; Schlattner, Uwe; Bogner, Johannes R


    Ubiquitous mitochondrial creatine kinase (uMtCK) accumulates as macroenzyme creatine kinase type 2 (macro CK2) in the serum of HIV-infected patients under a tenofovir disoproxil fumarate (TDF)-containing antiretroviral regimen. The genesis and clinical significance of this finding is unclear. A prospective observational 5-year follow-up study was performed on those patients in which macro CK2 appearance was initially described ('TDF switch study' cohort). In addition, tenofovir (TFV), its prodrug TDF and its active, intracellular derivative TFV diphosphate (TDP) were tested in vitro for their effects on different key properties of uMtCK to clarify possible interactions of uMtCK with TFV compounds. In just under 5 years of continuous TDF treatment, only 4/12 (33%) patients remained macro CK2-positive, whereas 8/12 (66%) originally positive patients were macro CK2-negative at the end of follow-up. Prospective clinical follow-up data indicate that macro CK2 appearance under TDF is not associated with significant cell damage or occurrence of malignancies. A trend towards grade 1 hypophosphataemia suggests subclinical proximal tubular dysfunction in macro-CK2-positive patients, although it was not associated with a significant decrease in estimated glomerular filtration rate. In vitro, TFV, TDF and TDP did not interfere with uMtCK enzyme activity as competitive inhibitors or pseudo-substrates, but TFV and TDF stabilized the native uMtCK octameric structure in dilute solutions. Appearance of octameric uMtCK as macro CK2 in the serum of TDF-treated patients is suggested to result from a combination of low-level mitochondrial damage caused by subclinical renal tubular dysfunction together with possible compensatory uMtCK overexpression and a putative concomitant stabilization of uMtCK octamers by higher levels of TFV in proximal tubules.

  9. Fas-associated factor 1 interacts with protein kinase CK2 in vivo upon apoptosis induction

    DEFF Research Database (Denmark)

    Guerra, B; Boldyreff, B; Issinger, O G


    We show here that in several different cell lines protein kinase CK2 and Fas-associated factor 1 (FAF1) exist together in a complex which is stable to high monovalent salt concentration. The CK2/FAF1 complex formation is significantly increased after induction of apoptosis with various DNA damaging...... the view that protein kinase CK2 plays an important role in certain steps of apoptosis....

  10. Crystal structure of the catalytic subunit of protein kinase CK2 from Zea mays at 2.1 A resolution

    DEFF Research Database (Denmark)

    Niefind, K; Guerra, B; Pinna, L A


    CK2alpha is the catalytic subunit of protein kinase CK2, an acidophilic and constitutively active eukaryotic Ser/Thr kinase involved in cell proliferation. A crystal structure, at 2.1 A resolution, of recombinant maize CK2alpha (rmCK2alpha) in the presence of ATP and Mg2+, shows the enzyme in an ...

  11. Purification and characterization of recombinant protein kinase CK2 from Zea mays expressed in Escherichia coli

    DEFF Research Database (Denmark)

    Riera, Marta; Pages, Montserrat; Issinger, Olaf Georg


    Recombinant protein kinase subunits rmCK2alpha-1 and rmCK2beta-1 from Zea mays were expressed separately in Escherichia coli and assembled to a fully active tetrameric holoenzyme complex in vitro. The obtained maize holoenzyme was purified to homogeneity, biochemically characterized, and compared...... between the maize holoenzyme and the catalytic subunit from CK2 maize shows that the incorporation of the catalytic subunit into the holoenzyme leads to a 14-fold activation in the case of ATP and 8-fold activation in the case of GTP. The maize holoenzyme is about 10 times more sensitive towards CK2...

  12. Experience from the Great East Japan Earthquake response as the basis for revising the Japanese Disaster Medical Assistance Team (DMAT) training program. (United States)

    Anan, Hideaki; Akasaka, Osamu; Kondo, Hisayoshi; Nakayama, Shinichi; Morino, Kazuma; Homma, Masato; Koido, Yuichi; Otomo, Yasuhiro


    The objective of this study was to draft a new Japanese Disaster Medical Assistance Team (DMAT) training program based on the responses to the Great East Japan Earthquake. Working group members of the Japan DMAT Investigative Commission, Ministry of Health, Labour and Welfare, reviewed reports and academic papers on DMAT activities after the disaster and identified items in the current Japanese DMAT training program that should be changed. A new program was proposed that incorporates these changes. New topics that were identified to be added to the DMAT training program were hospital evacuation, preparations to receive DMATs at damaged hospitals, coordination when DMAT activities are prolonged, and safety management and communication when on board small helicopters. The use of wide-area transport was reviewed and changes were made to cover selection of various transport means including helicopter ambulances. Content related to confined space medicine was removed. The time spent on emergency medical information system (EMIS) practical training was increased. Redundant or similar content was combined and reorganized, and a revised DMAT training program that did not increase the overall training time was designed. The revised DMAT training program will provide practical training better suited to the present circumstances in Japan.

  13. Expression, purification and crystallization of the catalytic subunit of protein kinase CK2 from Zea mays

    DEFF Research Database (Denmark)

    Guerra, B; Niefind, K; Pinna, L A


    The catalytic (alpha) subunit of protein kinase CK2 (CK2alpha) was originally cloned and overexpressed in the Escherichia coli strain pT7-7/BL21(DE3). The protein has been purified to homogeneity and crystallized. The crystals belong to the monoclinic space group C2, they have unit-cell parameter...

  14. Expression and characterization of a recombinant maize CK-2 alpha subunit

    DEFF Research Database (Denmark)

    Boldyreff, B; Meggio, F; Dobrowolska, G


    CKIIB, one of the CK-2 like enzymes which have been isolated from maize, has been shown to be a monomeric enzyme that cross-reacts with anti CK-2 alpha specific antibodies suggesting a possible relationship between the two proteins (Dobrowolska et al. (1992) Eur. J. Biochem. 204, 299-303). In ord...

  15. Structure of protein kinase CK2: dimerization of the human beta-subunit

    DEFF Research Database (Denmark)

    Boldyreff, B; Mietens, U; Issinger, O G


    Protein kinase CK2 has been shown to be elevated in all so far investigated solid tumors and its catalytic subunit has been shown to serve as an oncogene product. CK2 is a heterotetrameric serine-threonine kinase composed of two catalytic (alpha and/or alpha') and two regulatory beta-subunits. Us...

  16. Drosophila Protein Kinase CK2: Genetics, Regulatory Complexity and Emerging Roles during Development

    Directory of Open Access Journals (Sweden)

    Mohna Bandyopadhyay


    Full Text Available CK2 is a Ser/Thr protein kinase that is highly conserved amongst all eukaryotes. It is a well-known oncogenic kinase that regulates vital cell autonomous functions and animal development. Genetic studies in the fruit fly Drosophila are providing unique insights into the roles of CK2 in cell signaling, embryogenesis, organogenesis, neurogenesis, and the circadian clock, and are revealing hitherto unknown complexities in CK2 functions and regulation. Here, we review Drosophila CK2 with respect to its structure, subunit diversity, potential mechanisms of regulation, developmental abnormalities linked to mutations in the gene encoding CK2 subunits, and emerging roles in multiple aspects of eye development. We examine the Drosophila CK2 “interaction map” and the eye-specific “transcriptome” databases, which raise the prospect that this protein kinase has many additional targets in the developing eye. We discuss the possibility that CK2 functions during early retinal neurogenesis in Drosophila and mammals bear greater similarity than has been recognized, and that this conservation may extend to other developmental programs. Together, these studies underscore the immense power of the Drosophila model organism to provide new insights and avenues to further investigate developmentally relevant targets of this protein kinase.

  17. CK2-dependent phosphorylation positively regulates stress-induced activation of Msn2 in Saccharomyces cerevisiae. (United States)

    Cho, Bo-Ram; Hahn, Ji-Sook


    CK2 is a highly conserved Ser/Thr protein kinase involved in a large number of cellular processes. Here, we demonstrate that CK2-dependent phosphorylation positively regulates Msn2/4, the general stress response transcriptional activators in Saccharomyces cerevisiae, in response to various types of environmental stress conditions. CK2 overexpression elicits hyperactivation of Msn2/4, whereas deletion of one of the CK2 catalytic subunits, especially CKA2, leads to reduced transcriptional activity of Msn2/4 in response to glucose starvation, H2O2, and lactic acid. The CKA2 deletion mutant also shows increased stress sensitivity. CK2 phosphorylates Ser194 and Ser638 in Msn2 and replacement of Ser638 with alanine leads to reduced Msn2 activity upon stress and reduced tolerance to H2O2 and lactic acid. CKA2 deletion mutant shows shorter nuclear retention time of Msn2 upon lactic acid stress, suggesting that CK2 might regulate nuclear localization of Msn2. However, Msn2S194A, S638A mutant shows normal nuclear import and export patterns upon stress, suggesting that CK2 might positively regulate the general stress response not only by direct phosphorylation of Msn2/4, but also by regulating cellular translocation machinery. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. GTP plus water mimics ATP in the active site of protein kianse CK2

    DEFF Research Database (Denmark)

    Niefind, K; Pütter, M; Guerra, B


    The structures of the catalytic subunit of protein kinase CK2 from Zea mays complexed with Mg2+ and with analogs of ATP or GTP were determined to 2.2 A resolution. Unlike most other protein kinases, CK2 from various sources shows 'dual-cosubstrate specificity', that is, the ability to efficiently...... use either ATP or GTP as a cosubstrate. The structures of these complexes demonstrate that water molecules are critical to switch the active site of CK2 from an ATP- to a GTP-compatible state. An understanding of the structural basis of dual-cosubstrate specificity may help in the design of drugs...

  19. Role of protein kinases CK1α and CK2 in multiple myeloma: regulation of pivotal survival and stress-managing pathways

    Directory of Open Access Journals (Sweden)

    Sabrina Manni


    Full Text Available Abstract Multiple myeloma (MM is a malignant tumor of transformed plasma cells. MM pathogenesis is a multistep process. This cancer can occur de novo (rarely or it can develop from monoclonal gammopathy of undetermined significance (most of the cases. MM can be asymptomatic (smoldering myeloma or clinically active. Malignant plasma cells exploit intrinsic and extrinsic bone marrow microenvironment-derived growth signals. Upregulation of stress-coping pathways is also instrumental to maintain MM cell growth. The phylogenetically related Ser/Thr kinases CSNK1A1 (CK1α and CSNK2 (CK2 have recently gained a growing importance in hematologic malignancies arising both from precursors and from mature blood cells. In multiple myeloma, CK1α or CK2 sustain oncogenic cascades, such as the PI3K/AKT, JAK/STAT, and NF-κB, as well as propel stress-related signaling that help in coping with different noxae. Data also suggest that these kinases modulate the delivery of growth factors and cytokines from the bone marrow stroma. The “non-oncogene addiction” phenotype generated by the increased activity of CK1α and CK2 in multiple myeloma contributes to malignant plasma cell proliferation and survival and represents an Achilles’ heel for the activity of small ATP competitive CK1α or CK2 inhibitors.

  20. The carboxy terminus of p53 mimics the polylysine effect of protein kinase CK2-catalyzed MDM2 phosphorylation

    DEFF Research Database (Denmark)

    Guerra, B; Götz, C; Wagner, P


    product p53 (amino acids 264-393 which also harbors the CK2beta interaction site at amino acids 287-340) mimicked the polylysine effect in all respects, ie. stimulation of phosphate incorporation by CK2 holoenzyme and inhibition in the presence of the catalytic CK2 alpha-subunit. Stimulation by p53...

  1. Constitutive Phosphorylation of STAT3 by the CK2-BLNK-CD5 Complex. (United States)

    Rozovski, Uri; Harris, David M; Li, Ping; Liu, Zhiming; Jain, Preetesh; Veletic, Ivo; Ferrajoli, Alessandra; Burger, Jan; O'Brien, Susan; Bose, Prithviraj; Thompson, Philip; Jain, Nitin; Wierda, William; Keating, Michael J; Estrov, Zeev


    In chronic lymphocytic leukemia (CLL), STAT3 is constitutively phosphorylated on serine 727 and plays a role in the pathobiology of CLL. However, what induces constitutive phosphorylation of STAT3 is currently unknown. Mass spectrometry was used to identify casein kinase 2 (CK2), a serine/threonine kinase that coimmunoprecipitated with serine phosphorylated STAT3 (pSTAT3). Furthermore, activated CK2 incubated with recombinant STAT3 induced phosphorylation of STAT3 on serine 727. Although STAT3 and CK2 are present in normal B- and T cells, STAT3 is not constitutively phosphorylated in these cells. Further study found that CD5 and BLNK coexpressed in CLL, but not in normal B- or T cells, are required for STAT3 phosphorylation. To elucidate the relationship of CD5 and BLNK to CK2 and STAT3, STAT3 was immunoprecipitated from CLL cells, and CK2, CD5, and BLNK were detected in the immunoprecipitate. Conversely, STAT3, CD5, and BLNK were in the immunoprecipitate of CLL cells immunoprecipitated with CK2 antibodies. Furthermore, siRNA knockdown of CD5 or BLNK, or treatment with CD5-neutralizing antibodies significantly reduced the levels of serine pSTAT3 in CLL cells. Finally, confocal microscopy determined that CD5 is cell membrane bound, and fractionation studies revealed that the CK2/CD5/BLNK/STAT3 complex remains in the cytoplasm, whereas serine pSTAT3 is shuttled to the nucleus.Implications: These data show that the cellular proteins CK2, CD5, and BLNK are required for constitutive phosphorylation of STAT3 in CLL. Whether this protein complex phosphorylates other proteins or inhibiting its activity would have clinical benefit in patients has yet to be determined. Mol Cancer Res; 15(5); 610-8. ©2017 AACR. ©2017 American Association for Cancer Research.

  2. RP1 Is a Phosphorylation Target of CK2 and Is Involved in Cell Adhesion (United States)

    Göttig, Stephan; Henschler, Reinhard; Markuly, Norbert; Kleber, Sascha; Faust, Michael; Mischo, Axel; Bauer, Stefan; Zweifel, Martin; Knuth, Alexander; Renner, Christoph; Wadle, Andreas


    RP1 (synonym: MAPRE2, EB2) is a member of the microtubule binding EB1 protein family, which interacts with APC, a key regulatory molecule in the Wnt signalling pathway. While the other EB1 proteins are well characterized the cellular function and regulation of RP1 remain speculative to date. However, recently RP1 has been implicated in pancreatic cancerogenesis. CK2 is a pleiotropic kinase involved in adhesion, proliferation and anti-apoptosis. Overexpression of protein kinase CK2 is a hallmark of many cancers and supports the malignant phenotype of tumor cells. In this study we investigate the interaction of protein kinase CK2 with RP1 and demonstrate that CK2 phosphorylates RP1 at Ser236 in vitro. Stable RP1 expression in cell lines leads to a significant cleavage and down-regulation of N-cadherin and impaired adhesion. Cells expressing a Phospho-mimicking point mutant RP1-ASP236 show a marked decrease of adhesion to endothelial cells under shear stress. Inversely, we found that the cells under shear stress downregulate endogenous RP1, most likely to improve cellular adhesion. Accordingly, when RP1 expression is suppressed by shRNA, cells lacking RP1 display significantly increased cell adherence to surfaces. In summary, RP1 phosphorylation at Ser236 by CK2 seems to play a significant role in cell adhesion and might initiate new insights in the CK2 and EB1 family protein association. PMID:23844040

  3. Raf-1/CK2 and RhoA/ROCK signaling promote TNF-α-mediated endothelial apoptosis via regulating vimentin cytoskeleton. (United States)

    Yang, Lifeng; Tang, Lian; Dai, Fan; Meng, Guoliang; Yin, Runting; Xu, Xiaole; Yao, Wenjuan


    Both RhoA/ROCK and Raf-1/CK2 pathway play essential roles in cell proliferation, apoptosis, differentiation, and multiple other common cellular functions. We previously reported that vimentin is responsible for TNF-α-induced cell apoptosis. Herein, we investigated the regulation of RhoA/ROCK and Raf-1/CK2 signaling on vimentin filaments and endothelial apoptosis mediated by TNF-α. Treatment with TNF-α significantly induced the activation of RhoA and ROCK, and the expression of ROCK1. RhoA deficiency could obviously inhibit ROCK activation and ROCK1 expression induced by TNF-α. Both RhoA deficiency and ROCK activity inhibition (Y-27632) greatly inhibited endothelial apoptosis and preserved cell viability in TNF-α-induced human umbilical vein endothelial cells (HUVECs). Also vimentin phosphorylation and the remodeling of vimentin or phospho-vimentin induced by TNF-α were obviously attenuated by RhoA suppression and ROCK inhibition. TNF-α-mediated vimentin cleavage was significantly inhibited by RhoA suppression and ROCK inhibition through decreasing the activation of caspase3 and 8. Furthermore, TNF-α treatment greatly enhanced the activation of Raf-1. Suppression of Raf-1 or CK2 by its inhibitor (GW5074 or TBB) blocked vimentin phosphorylation, remodeling and endothelial apoptosis, and preserved cell viability in TNF-α-induced HUVECs. However, Raf-1 inhibition showed no significant effect on TNF-α-induced ROCK expression and activation, suggesting that the regulation of Raf-1/CK2 signaling on vimentin was independent of ROCK. Taken together, these results indicate that both RhoA/ROCK and Raf-1/CK2 pathway are responsible for TNF-α-mediated endothelial cytotoxicity via regulating vimentin cytoskeleton. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. CK2 phosphorylation of Schistosoma mansoni HMGB1 protein regulates its cellular traffic and secretion but not its DNA transactions.

    Directory of Open Access Journals (Sweden)

    Isabel Caetano de Abreu da Silva

    Full Text Available BACKGROUND: The helminth Schistosoma mansoni parasite resides in mesenteric veins where fecundated female worms lay hundred of eggs daily. Some of the egg antigens are trapped in the liver and induce a vigorous granulomatous response. High Mobility Group Box 1 (HMGB1, a nuclear factor, can also be secreted and act as a cytokine. Schistosome HMGB1 (SmHMGB1 is secreted by the eggs and stimulate the production of key cytokines involved in the pathology of schistosomiasis. Thus, understanding the mechanism of SmHMGB1 release becomes mandatory. Here, we addressed the question of how the nuclear SmHMGB1 can reach the extracellular space. PRINCIPAL FINDINGS: We showed in vitro and in vivo that CK2 phosphorylation was involved in the nucleocytoplasmic shuttling of SmHMGB1. By site-directed mutagenesis we mapped the two serine residues of SmHMGB1 that were phosphorylated by CK2. By DNA bending and supercoiling assays we showed that CK2 phosphorylation of SmHMGB1 had no effect in the DNA binding activities of the protein. We showed by electron microscopy, as well as by cell transfection and fluorescence microscopy that SmHMGB1 was present in the nucleus and cytoplasm of adult schistosomes and mammalian cells. In addition, we showed that treatments of the cells with either a phosphatase or a CK2 inhibitor were able to enhance or block, respectively, the cellular traffic of SmHMGB1. Importantly, we showed by confocal microscopy and biochemically that SmHMGB1 is significantly secreted by S. mansoni eggs of infected animals and that SmHMGB1 that were localized in the periovular schistosomotic granuloma were phosphorylated. CONCLUSIONS: We showed that secretion of SmHMGB1 is regulated by phosphorylation. Moreover, our results suggest that egg-secreted SmHMGB1 may represent a new egg antigen. Therefore, the identification of drugs that specifically target phosphorylation of SmHMGB1 might block its secretion and interfere with the pathogenesis of schistosomiasis.

  5. Nuclear localization of the CK2α-subunit correlates with poor prognosis in Clear Cell Renal Cell Carcinoma

    DEFF Research Database (Denmark)

    Rabjerg, Maj; Guerra, Barbara; Oliván-Viguera, Aida


    Protein kinase CK2a, one of the two catalytic isoforms of the protein kinase CK2 has been shown to contribute to tumor development, tumor proliferation and suppression of apoptosis in various malignancies. We conducted this study to investigate CK2 expression in different subtypes of Renal Cell...... renal cortex. Nuclear protein expression of CK2a correlated in univariate analysis with poor Progression Free Survival (HR = 8.11, p = 0.016). Functional analyses (cell proliferation assay) revealed an inhibitory effect of Caki-2 cell growth following CK2 inhibition with CX-4945. Our results suggest...

  6. The protein kinase CK2(Andante) holoenzyme structure supports proposed models of autoregulation and trans-autophosphorylation

    DEFF Research Database (Denmark)

    Schnitzler, Alexander; Olsen, Birgitte Brinkmann; Issinger, Olaf-Georg


    heterotetramer. Circular trimeric aggregates in which one-half of the CK2α chains show the predicted inhibitory proximity between those regions were detected within the crystal packing of the human CK2 holoenzyme. Here, we present further in vitro support of the "regulation-by-aggregation" model......(Andante) that contains a CK2β variant mutated in a CK2α-contact helix and described to be responsible for a prolonged circadian rhythm in Drosophila. The increased propensity of CK2(Andante) to form aggregates with completely blocked active sites may contribute to this phenotype....

  7. CK2 phosphorylates Sec31 and regulates ER-To-Golgi trafficking.

    Directory of Open Access Journals (Sweden)

    Mayuko Koreishi

    Full Text Available Protein export from the endoplasmic reticulum (ER is an initial and rate-limiting step of molecular trafficking and secretion. This is mediated by coat protein II (COPII-coated vesicles, whose formation requires small GTPase Sar1 and 6 Sec proteins including Sec23 and Sec31. Sec31 is a component of the outer layer of COPII coat and has been identified as a phosphoprotein. The initiation and promotion of COPII vesicle formation is regulated by Sar1; however, the mechanism regulating the completion of COPII vesicle formation followed by vesicle release is largely unknown. Hypothesizing that the Sec31 phosphorylation may be such a mechanism, we identified phosphorylation sites in the middle linker region of Sec31. Sec31 phosphorylation appeared to decrease its association with ER membranes and Sec23. Non-phosphorylatable mutant of Sec31 stayed longer at ER exit sites and bound more strongly to Sec23. We also found that CK2 is one of the kinases responsible for Sec31 phosphorylation because CK2 knockdown decreased Sec31 phosphorylation, whereas CK2 overexpression increased Sec31 phosphorylation. Furthermore, CK2 knockdown increased affinity of Sec31 for Sec23 and inhibited ER-to-Golgi trafficking. These results suggest that Sec31 phosphorylation by CK2 controls the duration of COPII vesicle formation, which regulates ER-to-Golgi trafficking.

  8. Crystal structure of a C-terminal deletion mutant of human protein kinase CK2 catalytic subunit

    DEFF Research Database (Denmark)

    Ermakova, Inessa; Boldyreff, Brigitte; Issinger, Olaf-Georg


    Protein kinase CK2 (formerly called: casein kinase 2) is a heterotetrameric enzyme composed of two separate catalytic chains (CK2alpha) and a stable dimer of two non-catalytic subunits (CK2beta). CK2alpha is a highly conserved member of the superfamily of eukaryotic protein kinases. The crystal...... main regions of conformational plasticity and regulatory importance in eukaryotic protein kinases, in active conformations stabilized by extensive contacts to the N-terminal segment. This arrangement is in accordance with the constitutive activity of the enzyme. By structural superimposition of human...... CK2alpha in isolated form and embedded in the human CK2 holoenzyme the loop connecting the strands beta4 and beta5 and the ATP-binding loop were identified as elements of structural variability. This structural comparison suggests that the ATP-binding loop may be the key region by which the non...

  9. Regulation of taurine transport systems by protein kinase CK2 in mammalian cells

    DEFF Research Database (Denmark)

    Lambert, Ian Henry; Hansen, Daniel Bloch


    Maintaining cell volume is critical for cellular function yet shift in cell volume is a prerequisite for mitosis and apoptosis. The ubiquitously and evolutionary conserved serine/threonine kinase CK2 promotes cell survival and suppresses apoptosis. The present review describes how mammalian cells...

  10. Structure of the gene encoding the murine protein kinase CK2 beta subunit

    DEFF Research Database (Denmark)

    Boldyreff, B; Issinger, O G


    II restriction endonuclease, and several blocks of sequence in the 5' flanking region are conserved between mouse and human. Despite all of these common features, one of the most striking differences found concerns the human CK2 alpha subunit binding domain at position -170 to -239 of the human gene. This domain...

  11. Regulation of taurine homeostasis by protein kinase CK2 in mouse fibroblasts

    DEFF Research Database (Denmark)

    Hansen, Daniel Bloch; Guerra, Barbara; Jacobsen, Jack Hummeland


    Increased expression of the ubiquitous serine/threonine protein kinase CK2 has been associated with increased proliferative capacity and increased resistance towards apoptosis. Taurine is the primary organic osmolyte involved in cell volume control in mammalian cells, and shift in cell volume is ...

  12. The synthetic peptide CIGB-300 modulates CK2-dependent signaling pathways affecting the survival and chemoresistance of non-small cell lung cancer cell lines. (United States)

    Cirigliano, Stéfano M; Díaz Bessone, María I; Berardi, Damián E; Flumian, Carolina; Bal de Kier Joffé, Elisa D; Perea, Silvio E; Farina, Hernán G; Todaro, Laura B; Urtreger, Alejandro J


    Lung cancer is the most frequently diagnosed cancer and the leading cause of cancer-related deaths worldwide. Up to 80% of cancer patients are classified as non-small-cell lung cancer (NSCLC) and cisplatin remains as the gold standard chemotherapy treatment, despite its limited efficacy due to both intrinsic and acquired resistance. The CK2 is a Ser/Thr kinase overexpressed in various types of cancer, including lung cancer. CIGB-300 is an antitumor peptide with a novel mechanism of action, since it binds to CK2 substrates thus preventing the enzyme activity. The aim of this work was to analyze the effects of CIGB-300 treatment targeting CK2-dependent signaling pathways in NSCLC cell lines and whether it may help improve current chemotherapy treatment. The human NSCLC cell lines NCI-H125 and NIH-A549 were used. Tumor spheroids were obtained through the hanging-drop method. A cisplatin resistant A549 cell line was obtained by chronic administration of cisplatin. Cell viability, apoptosis, immunoblotting, immunofluorescence and luciferase reporter assays were used to assess CIGB-300 effects. A luminescent assay was used to monitor proteasome activity. We demonstrated that CIGB-300 induces an anti-proliferative response both in monolayer- and three-dimensional NSCLC models, presenting rapid and complete peptide uptake. This effect was accompanied by the inhibition of the CK2-dependent canonical NF-κB pathway, evidenced by reduced RelA/p65 nuclear levels and NF-κB protein targets modulation in both lung cancer cell lines, as well as conditionally reduced NF-κB transcriptional activity. In addition, NF-κB modulation was associated with enhanced proteasome activity, possibly through its α7/C8 subunit. Neither the peptide nor a classical CK2 inhibitor affected cytoplasmic β-CATENIN basal levels. Given that NF-κB activation has been linked to cisplatin-induced resistance, we explored whether CIGB-300 could bring additional therapeutic benefits to the standard

  13. Mapping the residues of protein kinase CK2 alpha subunit responsible for responsiveness to polyanionic inhibitors

    DEFF Research Database (Denmark)

    Vaglio, P; Sarno, S; Marin, O


    .5-5 micrograms/ml concentration range. Two other mutants defective in substrate recognition, R191, 195K198A and K79R80K83A, display either a 100-fold reduction or no alteration at all in heparin inhibition, respectively. In contrast sensitivity to heparin inhibition is increased 30-fold by a single mutation...

  14. The C-terminal domain of human grp94 protects the catalytic subunit of protein kinase CK2 (CK2alpha) against thermal aggregation. Role of disulfide bonds

    DEFF Research Database (Denmark)

    Roher, N; Miró, F; Boldyreff, B


    The C-terminal domain (residues 518-803) of the 94 kDa glucose regulated protein (grp94) was expressed in Escherichia coli as a fusion protein with a His6-N-terminal tag (grp94-CT). This truncated form of grp94 formed dimers and oligomers that could be dissociated into monomers by treatment...... ratios of 4 : 1. The presence of dithiothreitol markedly reduced the anti-aggregation effects of grp94-CT on CK2alpha without altering the solubility of the chaperone. It is concluded that the chaperone activity of the C-terminal domain of human grp94 requires the maintenance of its quaternary structure...... (dimers and oligomers), which seems to be stabilised by disulphide bonds....

  15. CK2(beta)tes gene encodes a testis-specific isoform of the regulatory subunit of casein kinase 2 in Drosophila melanogaster

    DEFF Research Database (Denmark)

    Kalmykova, Alla I; Shevelyov, Yuri Y; Polesskaya, Oksana O


    An earlier described CK2(beta)tes gene of Drosophila melanogaster is shown to encode a male germline specific isoform of regulatory beta subunit of casein kinase 2. Western-analysis using anti-CK2(beta)tes Ig revealed CK2(beta)tes protein in Drosophila testes extract. Expression of a CK2(beta...... and coimmunoprecipitation analysis of protein extract from Drosophila testes, we demonstrated an association between CK2(beta)tes and CK2alpha. Northern-analysis has shown that another regulatory (beta') subunit found recently in D. melanogaster genome is also testis-specific. Thus, we describe the first example of two...

  16. Isolation and characterization of a monoclonal anti-protein kinase CK2 beta-subunit antibody of the IgG class for the direct detection of CK2 beta-subunit in tissue cultures of various mammalian species and human tumors

    DEFF Research Database (Denmark)

    Nastainczyk, W; Schmidt-Spaniol, I; Boldyreff, B


    A murine monoclonal anti-protein kinase CK2 beta antibody was isolated and characterized. The antibody detects 1 pmol of purified recombinant CK2 beta-subunit after analysis on SDS-PAGE. Alternatively undenatured CK2 beta-subunit was detected by an ELISA assay either as recombinant CK2 beta-subun...

  17. Concerns of Disaster Medical Assistance Team (DMAT) members about troubles at the nuclear power plant: experience from the Niigata Chuetsu-Oki earthquake, 16 July 2007, in Japan. (United States)

    Akashi, Makoto; Kumagaya, Ken; Kondo, Hisayoshi; Hirose, Yasuo


    An earthquake measuring 6.8 on the Richter scale struck the Niigata-Chuetsu region of Japan at 10:13 on 16 July 2007. The earthquake was followed by the sustained occurrence of numerous aftershocks, delaying the reconstruction of community lifelines. The earthquake affected the Kashiwazaki-Kariwa nuclear power plants (NPPs), the biggest NPP site in the world. The earthquake caused damage to NPPs, resulting in a small amount of radioactive materials being released into the air and the sea. However, no significant effects were detected in the public and the environment. As medical response to this earthquake, 42 Disaster Medical Assistance Teams (DMATs) were sent to hospitals and first-aid care centers at the NPP site. In order to evaluate the perceptions of the deployed DMAT personnel regarding concerns about the health effects of radiation and information about the damage to NPPs, questionnaires were sent to 40 facilities that dispatched DMATs to the earthquake area. Most of them were concerned with the effects of radiation, and adequate information about the problems at the NPPs was not communicated to them. This preliminary study suggests that communication of information is extremely important for DMAT members in the case of disasters, in particular if there exists a possibility of radiation exposure, since radiation cannot be detected by our senses. DMAT members are critical to any mass casualty incident, whether caused by humans or nature. We have learned from this earthquake that there is urgent need for an all-hazards approach, including a "combined disaster" strategy, which should be emphasized for current disaster planning and response. This is the first report on DMATs deployed to an earthquake site with damage to NPPs.

  18. Biophysical characterization of the structural change of Nopp140, an intrinsically disordered protein, in the interaction with CK2α

    Energy Technology Data Exchange (ETDEWEB)

    Na, Jung-Hyun [Department of Chemistry, Kookmin University, Jeongneung-dong, Seongbuk-gu, Seoul 02707 (Korea, Republic of); Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 02792 (Korea, Republic of); Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760 (Korea, Republic of); Lee, Won-Kyu [Department of Chemistry, Kookmin University, Jeongneung-dong, Seongbuk-gu, Seoul 02707 (Korea, Republic of); Kim, Yuyoung; Jeong, Cherlhyun [Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 02792 (Korea, Republic of); Song, Seung Soo [Department of Chemistry, Kookmin University, Jeongneung-dong, Seongbuk-gu, Seoul 02707 (Korea, Republic of); Cha, Sun-Shin [Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760 (Korea, Republic of); Han, Kyou-Hoon [Division of Biosystems Research, Korea Research Institute of Bioscience and Biotechnology, Daejeon 34141 (Korea, Republic of); Shin, Yeon-Kyun [Biomedical Research Institute, Korea Institute of Science and Technology, Seoul 02792 (Korea, Republic of); Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011 (United States); Yu, Yeon Gyu, E-mail: [Department of Chemistry, Kookmin University, Jeongneung-dong, Seongbuk-gu, Seoul 02707 (Korea, Republic of)


    Nucleolar phosphoprotein 140 (Nopp140) is a nucleolar protein, more than 80% of which is disordered. Previous studies have shown that the C-terminal region of Nopp140 (residues 568–596) interacts with protein kinase CK2α, and inhibits the catalytic activity of CK2. Although the region of Nopp140 responsible for the interaction with CK2α was identified, the structural features and the effect of this interaction on the structure of Nopp140 have not been defined due to the difficulty of structural characterization of disordered protein. In this study, the disordered feature of Nopp140 and the effect of CK2α on the structure of Nopp140 were examined using single-molecule fluorescence resonance energy transfer (smFRET) and electron paramagnetic resonance (EPR). The interaction with CK2α was increased conformational rigidity of the CK2α-interacting region of Nopp140 (Nopp140C), suggesting that the disordered and flexible conformation of Nopp140C became more rigid conformation as it binds to CK2α. In addition, site specific spin labeling and EPR analysis confirmed that the residues 574–589 of Nopp140 are critical for binding to CK2α. Similar technical approaches can be applied to analyze the conformational changes in other IDPs during their interactions with binding partners. - Highlights: • Nopp140 is intrinsically disordered protein (IDP). • Conformation of Nopp140 became more rigid conformation due to interaction with CK2α. • smFRET and EPR could be applied to analyze the structural changes of IDPs.

  19. Disruption of the regulatory beta subunit of protein kinase CK2 in mice leads to a cell-autonomous defect and early embryonic lethality

    DEFF Research Database (Denmark)

    Buchou, Thierry; Vernet, Muriel; Blond, Olivier


    Protein kinase CK2 is a ubiquitous protein kinase implicated in proliferation and cell survival. Its regulatory beta subunit, CK2beta, which is encoded by a single gene in mammals, has been suspected of regulating other protein kinases. In this work, we show that knockout of the CK2beta gene in m...

  20. CK2 Oppositely Modulates l-DOPA-Induced Dyskinesia via Striatal Projection Neurons Expressing D1 or D2 Receptors. (United States)

    Cortés, Marisol; Malave, Lauren; Castello, Julia; Flajolet, Marc; Cenci, M Angela; Friedman, Eitan; Rebholz, Heike


    We have previously shown that casein kinase 2 (CK2) negatively regulates dopamine D1 and adenosine A 2A receptor signaling in the striatum. Ablation of CK2 in D1 receptor-positive striatal neurons caused enhanced locomotion and exploration at baseline, whereas CK2 ablation in D2 receptor-positive neurons caused increased locomotion after treatment with A 2A antagonist, caffeine. Because both, D1 and A 2A receptors, play major roles in the cellular responses to l-DOPA in the striatum, these findings prompted us to examine the impact of CK2 ablation on the effects of l-DOPA treatment in the unilateral 6-OHDA lesioned mouse model of Parkinson's disease. We report here that knock-out of CK2 in striatonigral neurons reduces the severity of l-DOPA-induced dyskinesia (LID), a finding that correlates with lowered pERK but unchanged pPKA substrate levels in D1 medium spiny neurons as well as in cholinergic interneurons. In contrast, lack of CK2 in striatopallidal neurons enhances LID and ERK phosphorylation. Coadministration of caffeine with a low dose of l-DOPA reduces dyskinesia in animals with striatopallidal knock-out to wild-type levels, suggesting a dependence on adenosine receptor activity. We also detect reduced G olf levels in the striatonigral but not in the striatopallidal knock-out in response to l-DOPA treatment.Our work shows, in a rodent model of PD, that treatment-induced dyskinesia and striatal ERK activation are bidirectionally modulated by ablating CK2 in D1- or D2-positive projection neurons, in male and female mice. The results reveal that CK2 regulates signaling events critical to LID in each of the two main populations of striatal neurons. SIGNIFICANCE STATEMENT To date, l-DOPA is the most effective treatment for PD. Over time, however, its efficacy decreases, and side effects including l-DOPA-induced dyskinesia (LID) increase, affecting up to 78% of patients within 10 years of therapy (Hauser et al., 2007). It is understood that supersensitivity of

  1. Mapping the residues of protein kinase CK2 implicated in substrate recognition

    DEFF Research Database (Denmark)

    Sarno, S; Boldyreff, B; Marin, O


    , hampering the calculation of kinetic parameters. In contrast 3 mutants (K74-77A, K79R80K83A and R191,195K198A) phosphorylated the peptide with reduced efficiency accounted for by increased Km and decreased Vmax values. By using derivatives of the RRRADDSDDDDD peptide in which individual aspartyl residues......, respectively. These data support the conclusion that the basic residues present in the p+1 loop of CK2 alpha specifically recognize the acidic determinant adjacent to the C-terminal side of serine, while the specificity determinants located more down-stream are variably recognized by different residues...

  2. Structural and functional insights into the regulation mechanism of CK2 by IP6 and the intrinsically disordered protein Nopp140. (United States)

    Lee, Won-Kyu; Son, Sang Hyeon; Jin, Bong-Suk; Na, Jung-Hyun; Kim, Soo-Youl; Kim, Kook-Han; Kim, Eunice Eunkyeong; Yu, Yeon Gyu; Lee, Hyung Ho


    Protein kinase CK2 is a ubiquitous kinase that can phosphorylate hundreds of cellular proteins and plays important roles in cell growth and development. Deregulation of CK2 is related to a variety of human cancers, and CK2 is regarded as a suppressor of apoptosis; therefore, it is a target of anticancer therapy. Nucleolar phosphoprotein 140 (Nopp140), which is an intrinsically disordered protein, interacts with CK2 and inhibits the latter's catalytic activity in vitro. Interestingly, the catalytic activity of CK2 is recovered in the presence of d-myo-inositol 1,2,3,4,5,6-hexakisphosphate (IP6). IP6 is widely distributed in animal cells, but the molecular mechanisms that govern its cellular functions in animal cells have not been completely elucidated. In this study, the crystal structure of CK2 in complex with IP6 showed that the lysine-rich cluster of CK2 plays an important role in binding to IP6. The biochemical experiments revealed that a Nopp140 fragment (residues 568-596) and IP6 competitively bind to the catalytic subunit of CK2 (CK2α), and phospho-Ser574 of Nopp140 significantly enhances its interaction with CK2α. Substitutions of K74E, K76E, and K77E in CK2α significantly reduced the interactions of CK2α with both IP6 and the Nopp140-derived peptide. Our study gives an insight into the regulation of CK2. In particular, our work suggests that CK2 activity is inhibited by Nopp140 and reactivated by IP6 by competitive binding at the substrate recognition site of CK2.

  3. Protein kinase CK2 mutants defective in substrate recognition. Purification and kinetic analysis

    DEFF Research Database (Denmark)

    Sarno, S; Vaglio, P; Meggio, F


    of the recombinant beta subunit. By this latter procedure five mutated tetrameric holoenzymes were obtained as judged from their subunit composition, sedimentation coefficient on sucrose gradient ultracentrifugation, and increased activity toward a specific peptide substrate as compared with the isolated alpha......Five mutants of protein kinase CK2 alpha subunit in which altogether 14 basic residues were singly to quadruply replaced by alanines (K74A,K75A,K76A,K77A; K79A, R80A,K83A; R191A,R195A,K198A; R228A; and R278A, K279A,R280A) have been purified to near homogeneity either as such or after addition......A; and R191A,R195A, K198A, display dramatically lower phosphorylation efficiency and 8-50-fold higher Km values with the parent peptide, symptomatic of reduced attitude to bind the peptide substrate as compared with CK2 wild type. Such differences either disappear or are attentuated if the mutants R...

  4. Protein kinase CK2 potentiates translation efficiency by phosphorylating eIF3j at Ser127. (United States)

    Borgo, Christian; Franchin, Cinzia; Salizzato, Valentina; Cesaro, Luca; Arrigoni, Giorgio; Matricardi, Laura; Pinna, Lorenzo A; Donella-Deana, Arianna


    In eukaryotic protein synthesis the translation initiation factor 3 (eIF3) is a key player in the recruitment and assembly of the translation initiation machinery. Mammalian eIF3 consists of 13 subunits, including the loosely associated eIF3j subunit that plays a stabilizing role in the eIF3 complex formation and interaction with the 40S ribosomal subunit. By means of both co-immunoprecipitation and mass spectrometry analyses we demonstrate that the protein kinase CK2 interacts with and phosphorylates eIF3j at Ser127. Inhibition of CK2 activity by CX-4945 or down-regulation of the expression of CK2 catalytic subunit by siRNA cause the dissociation of j-subunit from the eIF3 complex as judged from glycerol gradient sedimentation. This finding proves that CK2-phosphorylation of eIF3j is a prerequisite for its association with the eIF3 complex. Expression of Ser127Ala-eIF3j mutant impairs both the interaction of mutated j-subunit with the other eIF3 subunits and the overall protein synthesis. Taken together our data demonstrate that CK2-phosphorylation of eIF3j at Ser127 promotes the assembly of the eIF3 complex, a crucial step in the activation of the translation initiation machinery. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Apigenin inhibits proliferation and induces apoptosis in human multiple myeloma cells through targeting the trinity of CK2, Cdc37 and Hsp90. (United States)

    Zhao, Ming; Ma, Jian; Zhu, Hai-Yan; Zhang, Xu-Hui; Du, Zhi-Yan; Xu, Yuan-Ji; Yu, Xiao-Dan


    Multiple myeloma (MM) is a B-cell malignancy that is largely incurable and is characterized by the accumulation of malignant plasma cells in the bone marrow. Apigenin, a common flavonoid, has been reported to suppress proliferation in a wide variety of solid tumors and hematological cancers; however its mechanism is not well understood and its effect on MM cells has not been determined. In this study, we investigated the effects of apigenin on MM cell lines and on primary MM cells. Cell viability assays demonstrated that apigenin exhibited cytotoxicity against both MM cell lines and primary MM cells but not against normal peripheral blood mononuclear cells. Together, kinase assays, immunoprecipitation and western blot analysis showed that apigenin inhibited CK2 kinase activity, decreased phosphorylation of Cdc37, disassociated the Hsp90/Cdc37/client complex and induced the degradation of multiple kinase clients, including RIP1, Src, Raf-1, Cdk4 and AKT. By depleting these kinases, apigenin suppressed both constitutive and inducible activation of STAT3, ERK, AKT and NF-κB. The treatment also downregulated the expression of the antiapoptotic proteins Mcl-1, Bcl-2, Bcl-xL, XIAP and Survivin, which ultimately induced apoptosis in MM cells. In addition, apigenin had a greater effects in depleting Hsp90 clients when used in combination with the Hsp90 inhibitor geldanamycin and the histone deacetylase inhibitor vorinostat. Our results suggest that the primary mechanisms by which apigenin kill MM cells is by targeting the trinity of CK2-Cdc37-Hsp90, and this observation reveals the therapeutic potential of apigenin in treating multiple myeloma.

  6. Protein kinase CK2 is coassembled with small conductance Ca(2+)-activated K+ channels and regulates channel gating

    DEFF Research Database (Denmark)

    Bildl, Wolfgang; Strassmaier, Tim; Thurm, Henrike


    and serves as the Ca2+ sensor. Here we show that, in addition, the cytoplasmic N and C termini of the channel protein form a polyprotein complex with the catalytic and regulatory subunits of protein kinase CK2 and protein phosphatase 2A. Within this complex, CK2 phosphorylates calmodulin at threonine 80......, reducing by 5-fold the apparent Ca2+ sensitivity and accelerating channel deactivation. The results show that native SK channels are polyprotein complexes and demonstrate that the balance between kinase and phosphatase activities within the protein complex shapes the hyperpolarizing response mediated by SK...

  7. The functional interplay between protein kinase CK2 and CCA1 transcriptional activity is essential for clock temperature compensation in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Sergi Portolés


    Full Text Available Circadian rhythms are daily biological oscillations driven by an endogenous mechanism known as circadian clock. The protein kinase CK2 is one of the few clock components that is evolutionary conserved among different taxonomic groups. CK2 regulates the stability and nuclear localization of essential clock proteins in mammals, fungi, and insects. Two CK2 regulatory subunits, CKB3 and CKB4, have been also linked with the Arabidopsis thaliana circadian system. However, the biological relevance and the precise mechanisms of CK2 function within the plant clockwork are not known. By using ChIP and Double-ChIP experiments together with in vivo luminescence assays at different temperatures, we were able to identify a temperature-dependent function for CK2 modulating circadian period length. Our study uncovers a previously unpredicted mechanism for CK2 antagonizing the key clock regulator CIRCADIAN CLOCK-ASSOCIATED 1 (CCA1. CK2 activity does not alter protein accumulation or subcellular localization but interferes with CCA1 binding affinity to the promoters of the oscillator genes. High temperatures enhance the CCA1 binding activity, which is precisely counterbalanced by the CK2 opposing function. Altering this balance by over-expression, mutation, or pharmacological inhibition affects the temperature compensation profile, providing a mechanism by which plants regulate circadian period at changing temperatures. Therefore, our study establishes a new model demonstrating that two opposing and temperature-dependent activities (CCA1-CK2 are essential for clock temperature compensation in Arabidopsis.

  8. CK2 targeted RNAi therapeutic delivered via malignant cell-directed tenfibgen nanocapsule: dose and molecular mechanisms of response in xenograft prostate tumors (United States)

    Vogel, Rachel I.; Shaughnessy, Daniel P.; Nacusi, Lucas; Korman, Vicci L.; Li, Yingming; Dehm, Scott M.; Zimmerman, Cheryl L.; Niehans, Gloria A.; Unger, Gretchen M.; Trembley, Janeen H.


    CK2, a protein serine/threonine kinase, promotes cell proliferation and suppresses cell death. This essential-for-survival signal demonstrates elevated expression and activity in all cancers examined, and is considered an attractive target for cancer therapy. Here, we present data on the efficacy of a tenfibgen (TBG) coated nanocapsule which delivers its cargo of siRNA (siCK2) or single stranded RNA/DNA oligomers (RNAi-CK2) simultaneously targeting CK2α and α′ catalytic subunits. Intravenous administration of TBG-siCK2 or TBG-RNAi-CK2 resulted in significant xenograft tumor reduction at low doses in PC3-LN4 and 22Rv1 models of prostate cancer. Malignant cell uptake and specificity in vivo was verified by FACS analysis and immunofluorescent detection of nanocapsules and PCR detection of released oligomers. Dose response was concordant with CK2αα′ RNA transcript levels and the tumors demonstrated changes in CK2 protein and in markers of proliferation and cell death. Therapeutic response corresponded to expression levels for argonaute and GW proteins, which function in oligomer processing and translational repression. No toxicity was detected in non-tumor tissues or by serum chemistry. Tumor specific delivery of anti-CK2 RNAi via the TBG nanoencapsulation technology warrants further consideration of translational potential. PMID:27557516

  9. Isolation and characterization of a monoclonal anti CK-2 alpha subunit antibody of the IgG1 subclass

    DEFF Research Database (Denmark)

    Schmidt-Spaniol, I; Boldyreff, B; Issinger, O G


    A monoclonal antibody was produced against the recombinant human alpha subunit of CK-2. The antibody was of the IgG1 subclass and it was isolated from serum-free cell culture media and purified by affinity chromatography on Protein G Sepharose. The antibody can be used to detect specifically the ...

  10. Mammalian FMRP S499 Is Phosphorylated by CK2 and Promotes Secondary Phosphorylation of FMRP. (United States)

    Bartley, Christopher M; O'Keefe, Rachel A; Blice-Baum, Anna; Mihailescu, Mihaela-Rita; Gong, Xuan; Miyares, Laura; Karaca, Esra; Bordey, Angélique


    The fragile X mental retardation protein (FMRP) is an mRNA-binding regulator of protein translation that associates with 4-6% of brain transcripts and is central to neurodevelopment. Autism risk genes' transcripts are overrepresented among FMRP-binding mRNAs, and FMRP loss-of-function mutations are responsible for fragile X syndrome, the most common cause of monogenetic autism. It is thought that FMRP-dependent translational repression is governed by the phosphorylation of serine residue 499 (S499). However, recent evidence suggests that S499 phosphorylation is not modulated by metabotropic glutamate receptor class I (mGluR-I) or protein phosphatase 2A (PP2A), two molecules shown to regulate FMRP translational repression. Moreover, the mammalian FMRP S499 kinase remains unknown. We found that casein kinase II (CK2) phosphorylates murine FMRP S499. Further, we show that phosphorylation of FMRP S499 permits phosphorylation of additional, nearby residues. Evidence suggests that these nearby residues are modulated by mGluR-I and PP2A pathways. These data support an alternative phosphodynamic model of FMRP that is harmonious with prior studies and serves as a framework for further investigation.

  11. Sphingosine kinase 1 mediates diabetic renal fibrosis via NF-κB signaling pathway: involvement of CK2α. (United States)

    Huang, Junying; Li, Jingyan; Chen, Zhiquan; Li, Jie; Chen, Qiuhong; Gong, Wenyan; Liu, Peiqing; Huang, Heqing


    Sphingosine kinase 1 (SphK1) plays a pivotal role in regulating diabetic renal fibrotic factors such as fibronectin (FN) and intercellular adhesion molecule-1 (ICAM-1). Especially, activation of SphK1 is closely linked to the body inflammatory reaction. Casein kinase 2α subunit (CK2α), a protein kinase related to inflammatory reaction, influences diabetic renal fibrosis and expressions of FN and ICAM-1 via NF-κB pathway. However, the mechanism by which SphK1 mediates diabetic renal fibrosis has not yet fully elucidated. The current study is aimed to investigate if SphK1 mediates diabetic renal fibrotic pathological process via inflammatory pathway and activation of CK2α. The following findings were observed: (1) Expressions of SphK1 were upregulated in kidneys of diabetic mice and rats; (2) Knockdown of SphK1 expression suppressed high glucose (HG)-induced NF-κB nuclear translocation and expressions of FN and ICAM-1; (3) Compared with C57 diabetic mice, SphK1 -/- diabetic mice exhibited less renal fibrotic lesions, FN accumulation and NF-κB nuclear accumulation in glomeruli of kidneys; (4) SphK1 mediated phosphorylation of CK2α, while CK2α knockdown depressed SphK1-induced activation of NF-κB pathway. This study indicates the essential role of SphK1 in regulating activation of CK2α and diabetic renal fibrotic pathological process via NF-κB.

  12. Phosphorylation of the Fas associated factor FAF1 by protein kinase CK2 and identification of serines 289 and 291 as the in vitro phosphorylation sites

    DEFF Research Database (Denmark)

    Jensen, H H; Hjerrild, M; Guerra, B


    obtained evidence that CK2 is the major cellular kinase responsible for FAF1 phosphorylation, using tissue extracts as kinase sources. By MALDI-MS we identified the two serine residues at positions 289 and 291 as the major in vitro CK2 phosphorylation sites. These data may help us elucidate the functions...

  13. Characterization of protein kinase CK2 protein subunits and p53 in F9 teratocarcinoma cells in the absence and presence of cisplatin

    DEFF Research Database (Denmark)

    Küpper, M; Köster, M; Schmidt-Spaniol, I


    The effect of cis-diaminedichloroplatinum(II) (cisplatin) on the induction of p53 and protein kinase CK2 activity was studied in the mouse teratocarcinoma cell line F9. Treatment of the cells with the chemotherapeutic agent cisplatin led to the detection of p53 3 h after addition of the drug. F9...... cell extracts treated with and without cisplatin were analyzed by ion exchange chromatography for protein kinase CK2 alpha/beta subunits and p53 distribution. The following results were obtained: (a) in crude extracts of cisplatin-treated cells, CK2 activity was sometimes reduced by as much as 50%; (b......) after separation by anionic exchange chromatography (MA7Q, BioRad) of the crude cellular extracts from cisplatin-treated cells, lower CK2 activity was found in the peak fractions confirming the results obtained with crude cellular extracts; (c) besides the detection of CK2 alpha subunit...

  14. CK2 phospho-independent assembly of the Tel2-associated stress-signaling complexes in Schizosaccharomyces pombe. (United States)

    Inoue, Haruna; Sugimoto, Shizuka; Takeshita, Yumiko; Takeuchi, Miho; Hatanaka, Mitsuko; Nagao, Koji; Hayashi, Takeshi; Kokubu, Aya; Yanagida, Mitsuhiro; Kanoh, Junko


    An evolutionarily conserved protein Tel2 regulates a variety of stress signals. In mammals, TEL2 associates with TTI1 and TTI2 to form the Triple T (TTT: TEL2-TTI1-TTI2) complex as well as with all the phosphatidylinositol 3-kinase-like kinases (PIKKs) and the R2TP (Ruvbl1-Ruvbl2-Tah1-Pih1 in budding yeast)/prefoldin-like complex that associates with HSP90. The phosphorylation of TEL2 by casein kinase 2 (CK2) enables direct binding of PIHD1 (mammalian Pih1) to TEL2 and is important for the stability and the functions of PIKKs. However, the regulatory mechanisms of Tel2 in fission yeast Schizosaccharomyces pombe remain largely unknown. Here, we report that S. pombe Tel2 is phosphorylated by CK2 at Ser490 and Thr493. Tel2 forms the TTT complex with Tti1 and Tti2 and also associates with PIKKs, Rvb2, and Hsp90 in vivo; however, the phosphorylation of Tel2 affects neither the stability of the Tel2-associated proteins nor their association with Tel2. Thus, Tel2 stably associates with its binding partners irrespective of its phosphorylation. Furthermore, the Tel2 phosphorylation by CK2 is not required for the various stress responses to which PIKKs are pivotal. Our results suggest that the Tel2-containing protein complexes are conserved among eukaryotes, but the molecular regulation of their formation has been altered during evolution. © 2016 Molecular Biology Society of Japan and John Wiley & Sons Australia, Ltd.

  15. Therapeutic Targeting of Protein Kinase CK2 Gene Expression in Feline Oral Squamous Cell Carcinoma: A Naturally Occurring Large-Animal Model of Head and Neck Cancer. (United States)

    Cannon, Claire M; Trembley, Janeen H; Kren, Betsy T; Unger, Gretchen M; O'Sullivan, M Gerard; Cornax, Ingrid; Modiano, Jaime F; Ahmed, Khalil


    Protein kinase CK2 (CK2) is a highly promising target for cancer therapy, and anti-CK2 gene expression therapy has shown effectiveness in rodent models of human head and neck cancer (HNC). To date, there has been no large-animal model of cancer in which to further explore anti-CK2 therapies. Feline oral squamous cell carcinoma (FOSCC) has been proposed as a large-animal model for human HNC, and we have previously shown that CK2 is a rational target in FOSCC. Here we have tested the hypothesis that a novel tenfibgen-coated tumor-specific nanocapsule carrying RNA interference (RNAi) oligonucleotides targeting feline CK2α and CK2α' (TBG-RNAi-fCK2αα') would be safe in cats with FOSCC; assessment of target inhibition and tumor response were secondary aims. Nine cats were enrolled and treated at two dose levels in a 3+3 escalation. Cats received a total of six treatments with TBG-RNAi-fCK2αα'. Pre- and posttreatment, tumor and normal oral mucosa biopsies were collected to assess CK2 expression, using immunohistochemistry (IHC) preparations evaluated by light microscopy. Toxicity and tumor response were assessed on the basis of standard criteria. The most common adverse events were grade 1 or 2 weight loss and anorexia. Grade 3 tissue necrosis was seen in association with tumor response in one cat, asymptomatic grade 4 elevations in aspartate transaminase and creatine phosphokinase in one cat, and asymptomatic grade 3 hypokalemia in one cat. Of six cats with evaluable biopsies, two had a reduction in CK2 IHC score in tumors after treatment. Four cats had progressive disease during the study period, three had stable disease, one had partial response, and response could not be evaluated in one cat. We conclude that the drug appeared safe and that there is some evidence of efficacy in FOSCC. Further investigation regarding dosing, schedule, target modulation, toxicity, and efficacy in a larger group of cats is warranted and may inform future clinical studies in human

  16. p21WAF1/CIP1 interacts with protein kinase CK2

    DEFF Research Database (Denmark)

    Götz, C; Wagner, P; Issinger, O G


    p21WAF1/CIP1 which belongs to a class of regulatory proteins that interact with cyclin dependent kinases is a potent inhibitor of these kinases. The inhibition of the cyclin dependent kinases induces an arrest of cells in the G phase of the cell cycle. In addition p21WAF1/CIP1 associates with PCN...

  17. Inhibitors (United States)

    ... and exercise, immune tolerance therapy, and needs of older adults with hemophilia and an inhibitor. For more information, visit The NHF’s Inhibitor Education Summits ...

  18. Protein Kinase CK2: A Targetable BCR-ABL Partner in Philadelphia Positive Leukemias


    Morotti, Alessandro; Carr?, Giovanna; Panuzzo, Cristina; Crivellaro, Sabrina; Taulli, Riccardo; Guerrasio, Angelo; Saglio, Giuseppe


    BCR-ABL-mediated leukemias, either Chronic Myeloid Leukemia (CML) or Philadelphia positive Acute Lymphoblastic Leukemia (ALL), are the paradigm of targeted molecular therapy of cancer due to the impressive clinical responses obtained with BCR-ABL specific tyrosine kinase inhibitors (TKIs). However, BCR-ABL TKIs do not allow completely eradicating both CML and ALL. Furthermore, ALL therapy is associated with much worse responses to TKIs than those observed in CML. The identification of additio...

  19. The regulatory beta-subunit of protein kinase CK2 regulates cell-cycle progression at the onset of mitosis

    DEFF Research Database (Denmark)

    Yde, C W; Olsen, B B; Meek, D


    Cell-cycle transition from the G(2) phase into mitosis is regulated by the cyclin-dependent protein kinase 1 (CDK1) in complex with cyclin B. CDK1 activity is controlled by both inhibitory phosphorylation, catalysed by the Myt1 and Wee1 kinases, and activating dephosphorylation, mediated by the CDC...... interference results in delayed cell-cycle progression at the onset of mitosis. Knockdown of CK2beta causes stabilization of Wee1 and increased phosphorylation of CDK1 at the inhibitory Tyr15. PLK1-Wee1 association is an essential event in the degradation of Wee1 in unperturbed cell cycle. We have found...... regulatory subunit, identifying it as a new component of signaling pathways that regulate cell-cycle progression at the entry of mitosis.Oncogene advance online publication, 12 May 2008; doi:10.1038/onc.2008.146....

  20. Inhibition of nucleoside diphosphate kinase activity by in vitro phosphorylation by protein kinase CK2. Differential phosphorylation of NDP kinases in HeLa cells in culture

    DEFF Research Database (Denmark)

    Biondi, R M; Engel, M; Sauane, M


    that in vitro protein kinase CK2 catalyzed phosphorylation of human NDPK A inhibits its enzymatic activity by inhibiting the first step of its ping-pong mechanism of catalysis: its autophosphorylation. Upon in vivo 32P labeling of HeLa cells, we observed that both human NDPKs, A and B, were autophosphorylated...

  1. The crystal structure of the complex of Zea mays alpha subunit with a fragment of human beta subunit provides the clue to the architecture of protein kinase CK2 holoenzyme

    DEFF Research Database (Denmark)

    Battistutta, R; Sarno, S; De Moliner, E


    The crystal structure of a complex between the catalytic alpha subunit of Zea mays CK2 and a 23-mer peptide corresponding the C-terminal sequence 181-203 of the human CK2 regulatory beta subunit has been determined at 3.16-A resolution. The complex, composed of two alpha chains and two peptides...

  2. Metastasis-associated protein Mts1 (S100A4) inhibits CK2-mediated phosphorylation and self-assembly of the heavy chain of nonmuscle myosin

    DEFF Research Database (Denmark)

    Kriajevska, M; Bronstein, I B; Scott, D J


    of Mts1. The short C-terminal fragment of the myosin heavy chain was totally soluble in the presence of an equimolar amount of Mts1 at low ionic conditions (50 mM NaCl). Depolymerization was found to be calcium-dependent and could be blocked by EGTA. Our data suggest that Mts1 can increase myosin...... a regulatory role in the myosin assembly. In the presence of calcium, Mts1 binds at the C-terminal end of the myosin heavy chain close to the site of phosphorylation by protein kinase CK2 (Ser1944). In the present study, we have shown that interaction of Mts1 with the human platelet myosin or C......-terminal fragment of the myosin heavy chain inhibits phosphorylation of the myosin heavy chain by protein kinase CK2 in vitro. Mts1 might also bind directly the beta subunit of protein kinase CK2, thereby modifying the enzyme activity. Our results indicate that myosin oligomers were disassembled in the presence...

  3. ck2-Dependent Phosphorylation of Progesterone Receptors (PR) on Ser81 Regulates PR-B Isoform-Specific Target Gene Expression in Breast Cancer Cells ▿ (United States)

    Hagan, Christy R.; Regan, Tarah M.; Dressing, Gwen E.; Lange, Carol A.


    Progesterone receptors (PR) are critical mediators of mammary gland development and contribute to breast cancer progression. Progestin-induced rapid activation of cytoplasmic protein kinases leads to selective regulation of growth-promoting genes by phospho-PR species. Herein, we show that phosphorylation of PR Ser81 is ck2 dependent and progestin regulated in intact cells but also occurs in the absence of PR ligands when cells enter the G1/S phase of the cell cycle. T47D breast cancer cells stably expressing a PR-B mutant receptor that cannot be phosphorylated at Ser79/81 (S79/81A) formed fewer soft agar colonies. Regulation of selected genes by PR-B, but not PR-A, also required Ser79/81 phosphorylation for basal and/or progestin-regulated (BIRC3, HSD11β2, and HbEGF) expression. Additionally, wild-type (wt) PR-B, but not S79/81A mutant PR, was robustly recruited to a progesterone response element (PRE)-containing transcriptional enhancer region of BIRC3; abundant ck2 also associated with this region in cells expressing wt but not S79/81A PR. We conclude that phospho-Ser81 PR provides a platform for ck2 recruitment and regulation of selected PR-B target genes. Understanding how ligand-independent PRs function in the context of high levels of kinase activities characteristic of breast cancer is critical to understanding the basis of tumor-specific changes in gene expression and will speed the development of highly selective treatments. PMID:21518957

  4. Modulation of LSD1 phosphorylation by CK2/WIP1 regulates RNF168-dependent 53BP1 recruitment in response to DNA damage. (United States)

    Peng, Bin; Wang, Jing; Hu, Yuan; Zhao, Hongli; Hou, Wenya; Zhao, Hongchang; Wang, Hailong; Liao, Ji; Xu, Xingzhi


    Proper DNA damage response is essential for the maintenance of genome integrity. The E3 ligase RNF168 deficiency fully prevents both the initial recruitment and retention of 53BP1 at sites of DNA damage. In response to DNA damage, RNF168-dependent recruitment of the lysine-specific demethylase LSD1 to the site of DNA damage promotes local H3K4me2 demethylation and ubiquitination of H2A/H2AX, facilitating 53BP1 recruitment to sites of DNA damage. Alternatively, RNF168-mediated K63-linked ubiquitylation of 53BP1 is required for the initial recruitment of 53BP1 to sites of DNA damage and for its function in repair. We demonstrated here that phosphorylation and dephosphorylation of LSD1 at S131 and S137 was mediated by casein kinase 2 (CK2) and wild-type p53-induced phosphatase 1 (WIP1), respectively. LSD1, RNF168 and 53BP1 interacted with each other directly. CK2-mediated phosphorylation of LSD1 exhibited no impact on its interaction with 53BP1, but promoted its interaction with RNF168 and RNF168-dependent 53BP1 ubiquitination and subsequent recruitment to the DNA damage sites. Furthermore, overexpression of phosphorylation-defective mutants failed to restore LSD1 depletion-induced cellular sensitivity to DNA damage. Taken together, our results suggest that LSD1 phosphorylation modulated by CK2/WIP1 regulates RNF168-dependent 53BP1 recruitment directly in response to DNA damage and cellular sensitivity to DNA damaging agents. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Role of CK2-dependent phosphorylation of Ifh1 and Crf1 in transcriptional regulation of ribosomal protein genes in Saccharomyces cerevisiae. (United States)

    Kim, Myung Sup; Hahn, Ji-Sook


    In Saccharomyces cerevisiae, Fhl1 is involved in the regulation of ribosomal protein (RP) genes through interaction with either its coactivator Ifh1 or corepressor Crf1, depending on nutrient conditions. Interaction of Fhl1 with Ifh1 or Crf1 is achieved through a forkhead-associated (FHA) domain of Fhl1, which binds to forkhead-binding (FHB) domains of Ifh1 and Crf1. Here, we demonstrate that CK2-dependent phosphorylation of T681 and T348 residues, located in the FHB domains of Ifh1 and Crf1, respectively, provides binding sites for the FHA domain of Fhl1. Cells expressing Ifh1(T681A) mutant showed reduced association of Ifh1 at the RP gene promoters and decreased levels of RP gene transcripts, thereby reducing the growth rate. On the other hand, cells expressing Crf1(T348A) showed a defect in repressing RP gene transcription upon inhibition of target of rapamycin complex 1 (TORC1) by rapamycin treatment. Taken together, these findings suggest the mechanisms by which CK2-dependent recruitment of Ifh1 and Crf1 at the RP gene promoters governs the transcription of RP genes. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Desregulació dels nivells de les subunitats alfa i beta de la proteïna quinasa CK2 en carcinoma renal de cèl·lules clares (ccRCC)


    Vilardell Vilà, Jordi


    La proteïna CK2 és una serina/treonina quinasa present en tots els organismes eucariotes i que actua sobre una àmplia varietat de substrats cel·lulars, implicats en una àmplia gamma de funcions diferents, moltes de les quals són essencials per la cèl·lula. De fet, CK2 ha estat considerada com una proteïna quinasa essencial per la viabilitat de les cèl·lules eucariotes. Les alteracions de CK2 en una àmplia varietat de tumors malignes s'han confirmat en diversos estudis, mostrant-se una activit...

  7. p53 and the ribosomal protein L5 participate in high molecular mass complex formation with protein kinase CK2 in murine teratocarcinoma cell line F9 after serum stimulation and cisplatin treatment

    DEFF Research Database (Denmark)

    Guerra, B; Issinger, O G


    Using the murine teratocarcinoma cell line F9 we investigated the influence of serum stimulation and cisplatin treatment on the p53, CK2, MDM2 levels. Both treatments led to an increase of p53, though with different kinetics; the other proteins investigated were not affected. We present direct...

  8. ITC-derived binding affinity may be biased due to titrant (nano-aggregation. Binding of halogenated benzotriazoles to the catalytic domain of human protein kinase CK2.

    Directory of Open Access Journals (Sweden)

    Maria Winiewska

    Full Text Available The binding of four bromobenzotriazoles to the catalytic subunit of human protein kinase CK2 was assessed by two complementary methods: Microscale Thermophoresis (MST and Isothermal Titration Calorimetry (ITC. New algorithm proposed for the global analysis of MST pseudo-titration data enabled reliable determination of binding affinities for two distinct sites, a relatively strong one with the Kd of the order of 100 nM and a substantially weaker one (Kd > 1 μM. The affinities for the strong binding site determined for the same protein-ligand systems using ITC were in most cases approximately 10-fold underestimated. The discrepancy was assigned directly to the kinetics of ligand nano-aggregates decay occurring upon injection of the concentrated ligand solution to the protein sample. The binding affinities determined in the reverse ITC experiment, in which ligands were titrated with a concentrated protein solution, agreed with the MST-derived data. Our analysis suggests that some ITC-derived Kd values, routinely reported together with PDB structures of protein-ligand complexes, may be biased due to the uncontrolled ligand (nano-aggregation, which may occur even substantially below the solubility limit.

  9. ITC-derived binding affinity may be biased due to titrant (nano)-aggregation. Binding of halogenated benzotriazoles to the catalytic domain of human protein kinase CK2 (United States)

    Winiewska, Maria; Bugajska, Ewa


    The binding of four bromobenzotriazoles to the catalytic subunit of human protein kinase CK2 was assessed by two complementary methods: Microscale Thermophoresis (MST) and Isothermal Titration Calorimetry (ITC). New algorithm proposed for the global analysis of MST pseudo-titration data enabled reliable determination of binding affinities for two distinct sites, a relatively strong one with the Kd of the order of 100 nM and a substantially weaker one (Kd > 1 μM). The affinities for the strong binding site determined for the same protein-ligand systems using ITC were in most cases approximately 10-fold underestimated. The discrepancy was assigned directly to the kinetics of ligand nano-aggregates decay occurring upon injection of the concentrated ligand solution to the protein sample. The binding affinities determined in the reverse ITC experiment, in which ligands were titrated with a concentrated protein solution, agreed with the MST-derived data. Our analysis suggests that some ITC-derived Kd values, routinely reported together with PDB structures of protein-ligand complexes, may be biased due to the uncontrolled ligand (nano)-aggregation, which may occur even substantially below the solubility limit. PMID:28273138

  10. Site-Specific Phosphorylation of Ikaros Induced by Low-Dose Ionizing Radiation Regulates Cell Cycle Progression of B Lymphoblast Through CK2 and AKT Activation

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Seong-Jun; Kang, Hana [KHNP Radiation Health Institute, Korea Hydro & Nuclear Power Co, Seoul (Korea, Republic of); Kim, Min Young [Department of Molecular Biology, College of Natural Sciences, Pusan National University, Busan (Korea, Republic of); Lee, Jung Eun; Kim, Sung Jin; Nam, Seon Young; Kim, Ji Young; Kim, Hee Sun [KHNP Radiation Health Institute, Korea Hydro & Nuclear Power Co, Seoul (Korea, Republic of); Pyo, Suhkneung [College of Pharmacy, Sungkyunkwan University, Suwon, Gyeonggi-do (Korea, Republic of); Yang, Kwang Hee, E-mail: [KHNP Radiation Health Institute, Korea Hydro & Nuclear Power Co, Seoul (Korea, Republic of)


    Purpose: To determine how low-dose ionizing radiation (LDIR) regulates B lympho-proliferation and its molecular mechanism related with Ikaros, transcription factor. Methods and Materials: Splenocytes and IM-9 cells were uniformly irradiated with various doses of a {sup 137}Cs γ-source, and cell proliferation was analyzed. To determine the LDIR-specific phosphorylation of Ikaros, immunoprecipitation and Western blot analysis were performed. To investigate the physiologic function of LDIR-mediatied Ikaros phosphorylation, Ikaros mutants at phosphorylation sites were generated, and cell cycle analysis was performed. Results: First, we found that LDIR enhances B lymphoblast proliferation in an Ikaros-dependent manner. Moreover, we found that LDIR elevates the phosphorylation level of Ikaros protein. Interestingly, we showed that CK2 and AKT are involved in LDIR-induced Ikaros phosphorylation and capable of regulating DNA binding activity of Ikaros via specific phosphorylation. Finally, we identified LDIR-specific Ikaros phosphorylation sites at S391/S393 and showed that the Ikaros phosphorylations at these sites control Ikaros's ability to regulate G1/S cell cycle progression. Conclusion: Low-dose ionizing radiation specifically phosphorylates Ikaros protein at Ser 391/393 residues to regulate cell cycle progression in B lymphoblast.

  11. Inactivation of the FoxO3a transcription factor is associated with the production of reactive oxygen species during protein kinase CK2 downregulation-mediated senescence in human colon cancer and breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Park, Seong-Yeol; Bae, Young-Seuk, E-mail:


    We previously showed that protein kinase CK2 downregulation mediates senescence through the reactive oxygen species (ROS)–p53–p21{sup Cip1/WAF1} pathway in various human cells. In the present study, we investigated whether the FoxO3a transcription factor is associated with ROS production during CK2 downregulation-induced senescence in human colon cancer HCT116 and breast cancer MCF-7 cells. FoxO3a overexpression suppressed ROS production and p53 stabilization induced by a CK2α knockdown. CK2α downregulation induced nuclear export of FoxO3a through stimulation of AKT-mediated phosphorylation of FoxO3a and decreased transcription of its target genes (Cu/ZnSOD, MnSOD, and catalase). In contrast, CK2α overexpression inhibited AKT-mediated FoxO3a phosphorylation. This resulted in nuclear accumulation of FoxO3a, and elevated expression of its target genes. Therefore, these data indicate for the first time that CK2 downregulation stimulates ROS generation by inhibiting FoxO3a during premature senescence in human colon and breast cancer cells. - Highlights: • FoxO3a overexpression inhibited ROS production mediated by CK2α knockdown. • CK2α downregulation induced nuclear export of FoxO3a via AKT activation. • CK2α downregulation reduced transcription of FoxO3a target genes including SOD. • CK2α upregulation elevated nuclear import and target gene expression of FoxO3a. • This study indicates that CK2 can modulate the intracellular ROS level via FoxO3a.

  12. Rational design of protein kinase inhibitors

    Directory of Open Access Journals (Sweden)

    Yarmoluk S. M.


    Full Text Available Modern methodological approaches to rational design of low molecular weight compounds with specific activity in relation to predetermined biomolecular targets are considered by example of development of high effective protein kinase inhibitors. The application of new computational methods that allow to significantly improve the quality of computational experiments (in, particular, accuracy of low molecular weight compounds activity prediction without increase of computational and time costs are highlighted. The effectiveness of strategy of rational design is demonstrated by examples of several own investigations devoted to development of new inhibitors that are high effective and selective towards protein kinases CK2, FGFR1 and ASK1.

  13. Halogenated imidazole derivatives block RNA polymerase II elongation along mitogen inducible genes

    Directory of Open Access Journals (Sweden)

    Rubel Tymon


    Full Text Available Abstract Background Aberrant activation of protein kinases is one of the essential oncogenic driving forces inherent to the process of tumorigenesis. The protein kinase CK2 plays an important role in diverse biological processes, including cell growth and proliferation as well as in the governing and transduction of prosurvival signals. Increased expression of CK2 is a hallmark of some cancers, hence its antiapoptotic properties may be relevant to cancer onset. Thus, the designing and synthesis of the CK2 inhibitors has become an important pursuit in the search for cancer therapies. Results Using a high-throughput microarray approach, we demonstrate that two potent inhibitors of CK2, 4,5,6,7-tetrabromo-benzimidazole (TBBz and 2-Dimethyloamino-4,5,6,7-tetrabromo-1H-benzimidazole (DMAT, blocked mitogen induced mRNA expression of immediate early genes. Given the impact of these inhibitors on the process of transcription, we investigated their effects on RNA Polymerase II (RNAPII elongation along the mitogen inducible gene, EGR1 (early growth response 1, using chromatin immunoprecipitation (ChIP assay. ChIP analysis demonstrated that both drugs arrest RNAPII elongation. Finally, we show that CDK9 kinase activity, essential for the triggering of RNAPII elongation, was blocked by TBBz and to lesser degree by DMAT. Conclusions Our approach revealed that small molecules derived from halogenated imidazole compounds may decrease cell proliferation, in part, by inhibiting pathways that regulate transcription elongation.

  14. Basic residues in the 74-83 and 191-198 segments of protein kinase CK2 catalytic subunit are implicated in negative but not in positive regulation by the beta-subunit

    DEFF Research Database (Denmark)

    Sarno, S; Vaglio, P; Marin, O


    by the beta-subunit many fold more than that of alpha wild type, while extrastimulation by beta mutant D55L56E57A, observable with alpha wild type, is abolished with these mutants. These data support the conclusion that down regulation by the acidic residues clustered in the N-terminal moiety of beta......Protein kinase CK2 is a ubiquitous pleiotropic serine/threonine protein kinase whose holoenzyme is comprised of two catalytic (alpha and/or alpha') and two non-catalytic, beta-subunits. The beta-subunit possesses antagonist functions that can be physically dissected by generating synthetic...... fragments encompassing its N-terminal and C-terminal domains. Here we show that by mutating basic residues in the 74-77 and in the 191-198 regions of the alpha-subunit, the negative regulation by the beta-subunit and by its N-terminal synthetic fragment CK2beta-(1-77), which is observable using calmodulin...

  15. Determination of mRNA, and protein levels of p53, MDM2 and protein kinase CK2 subunits in F9 cells after treatment with the apoptosis-inducing drugs cisplatin and carboplatin

    DEFF Research Database (Denmark)

    Siemer, S; Ornskov, D; Guerra, B


    cisplatin and carboplatin on the mRNA and protein levels of p53, MDM2 and CK2 in a murine teratocarcinoma cell line F9. Northern and Western blot analyses were performed and the CK2 activity was determined. The degree of apoptosis after drug treatment was assessed using the TUNEL test. Six hours after...... cisplatin and carboplatin treatment, the RNA level of p53 dropped by 59% +/- 9% and 86% +/- 8% respectively, whereas the observed level of p53 protein rose to 7 and 10 times over the untreated control, respectively. Treatment with 33 microM cisplatin prompted apoptosis as early as 4 h after drug treatment....... More than 50% apoptotic cells were seen after 6 h. We conclude that cisplatin and its second generation drug carboplatin act similarly i.e. both drugs cause a concomitant decrease in p53 mRNA and an increase in p53 protein level. After 4 h treatment with either of the two drugs, p53 levels reach...

  16. Stability of the Human Hsp90-p50Cdc37 Chaperone Complex against Nucleotides and Hsp90 Inhibitors, and the Influence of Phosphorylation by Casein Kinase 2 (United States)

    Olesen, Sanne H.; Ingles, Donna J.; Zhu, Jin-Yi; Martin, Mathew P.; Betzi, Stephane; Georg, Gunda I.; Tash, Joseph S.; Schönbrunn, Ernst


    The molecular chaperone Hsp90 is regulated by co-chaperones such as p50Cdc37, which recruits a wide selection of client protein kinases. Targeted disruption of the Hsp90-p50Cdc37 complex by protein-protein interaction (PPI) inhibitors has emerged as an alternative strategy to treat diseases characterized by aberrant Hsp90 activity. Using isothermal microcalorimetry, ELISA and GST-pull down assays we evaluated reported Hsp90 inhibitors and nucleotides for their ability to inhibit formation of the human Hsp90β-p50Cdc37 complex, reconstituted in-vitro from full-length proteins. Hsp90 inhibitors, including the proposed PPI inhibitors gedunin and H2-gamendazole, did not affect the interaction of Hsp90 with p50Cdc37 in vitro. Phosphorylation of Hsp90 and p50Cdc37 by casein kinase 2 (CK2) did not alter the thermodynamic signature of complex formation. However, the phosphorylated complex was vulnerable to disruption by ADP (IC50 = 32 µM), while ATP, AMPPNP and Hsp90 inhibitors remained largely ineffective. The differential inhibitory activity of ADP suggests that phosphorylation by CK2 primes the complex for dissociation in response to a drop in ATP/ADP levels. The approach applied herein provides robust assays for a comprehensive biochemical evaluation of potential effectors of the Hsp90-p50Cdc37 complex, such as phosphorylation by a kinase or the interaction with small molecule ligands. PMID:25608045

  17. Stability of the human Hsp90-p50Cdc37 chaperone complex against nucleotides and Hsp90 inhibitors, and the influence of phosphorylation by casein kinase 2. (United States)

    Olesen, Sanne H; Ingles, Donna J; Zhu, Jin-Yi; Martin, Mathew P; Betzi, Stephane; Georg, Gunda I; Tash, Joseph S; Schönbrunn, Ernst


    The molecular chaperone Hsp90 is regulated by co-chaperones such as p50Cdc37, which recruits a wide selection of client protein kinases. Targeted disruption of the Hsp90-p50Cdc37 complex by protein-protein interaction (PPI) inhibitors has emerged as an alternative strategy to treat diseases characterized by aberrant Hsp90 activity. Using isothermal microcalorimetry, ELISA and GST-pull down assays we evaluated reported Hsp90 inhibitors and nucleotides for their ability to inhibit formation of the human Hsp90β-p50Cdc37 complex, reconstituted in vitro from full-length proteins. Hsp90 inhibitors, including the proposed PPI inhibitors gedunin and H2-gamendazole, did not affect the interaction of Hsp90 with p50Cdc37 in vitro. Phosphorylation of Hsp90 and p50Cdc37 by casein kinase 2 (CK2) did not alter the thermodynamic signature of complex formation. However, the phosphorylated complex was vulnerable to disruption by ADP (IC50 = 32 µM), while ATP, AMPPNP and Hsp90 inhibitors remained largely ineffective. The differential inhibitory activity of ADP suggests that phosphorylation by CK2 primes the complex for dissociation in response to a drop in ATP/ADP levels. The approach applied herein provides robust assays for a comprehensive biochemical evaluation of potential effectors of the Hsp90-p50Cdc37 complex, such as phosphorylation by a kinase or the interaction with small molecule ligands.

  18. Stability of the Human Hsp90-p50Cdc37 Chaperone Complex against Nucleotides and Hsp90 Inhibitors, and the Influence of Phosphorylation by Casein Kinase 2

    Directory of Open Access Journals (Sweden)

    Sanne H. Olesen


    Full Text Available The molecular chaperone Hsp90 is regulated by co-chaperones such as p50Cdc37, which recruits a wide selection of client protein kinases. Targeted disruption of the Hsp90-p50Cdc37 complex by protein–protein interaction (PPI inhibitors has emerged as an alternative strategy to treat diseases characterized by aberrant Hsp90 activity. Using isothermal microcalorimetry, ELISA and GST-pull down assays we evaluated reported Hsp90 inhibitors and nucleotides for their ability to inhibit formation of the human Hsp90β-p50Cdc37 complex, reconstituted in vitro from full-length proteins. Hsp90 inhibitors, including the proposed PPI inhibitors gedunin and H2-gamendazole, did not affect the interaction of Hsp90 with p50Cdc37 in vitro. Phosphorylation of Hsp90 and p50Cdc37 by casein kinase 2 (CK2 did not alter the thermodynamic signature of complex formation. However, the phosphorylated complex was vulnerable to disruption by ADP (IC50 = 32 µM, while ATP, AMPPNP and Hsp90 inhibitors remained largely ineffective. The differential inhibitory activity of ADP suggests that phosphorylation by CK2 primes the complex for dissociation in response to a drop in ATP/ADP levels. The approach applied herein provides robust assays for a comprehensive biochemical evaluation of potential effectors of the Hsp90-p50Cdc37 complex, such as phosphorylation by a kinase or the interaction with small molecule ligands.

  19. [ALK inhibitor]. (United States)

    Mano, Hiroyuki


    While lung cancer is the leading cause of cancer deaths worldwide, the molecular mechanism underlying its carcinogenesis is mainly unknown. We have discovered a small, fusion-type tyrosine kinase EML4-ALK that is generated through a tiny inversion within the short arm of human chromosome 2. Transgenic mice expressing EML4-ALK in lung developed hundreds of lung cancer nodules soon after birth, but such nodules were readily eradicated upon treatment with an ALK inhibitor. Clinical trials for EML4-ALK-positive lung cancer with an ALK inhibitor is ongoing, with its interim results being highly promising.

  20. Angiogenesis Inhibitors (United States)

    ... blood vessels “feed” growing tumors with oxygen and nutrients , allowing the cancer cells to invade nearby tissue , to move throughout ... any angiogenesis inhibitors currently being used to treat cancer in humans? Yes. The U.S. Food and Drug Administration (FDA) has approved bevacizumab to ...

  1. Characterization of CK2 holoenzyme variants with regard to crystallization

    DEFF Research Database (Denmark)

    Guerra, B; Niefind, K; Ermakowa, I


    severely. One of the approaches chosen was the production of a chimeric holoenzyme made up from a human regulatory subunit and a catalytic subunit from Z. mays. The plant catalytic subunit, in contrast to the human counterpart is very stable and does not undergo this kind of degradation. The second...

  2. Alpha glucosidase inhibitors

    National Research Council Canada - National Science Library

    Kalra, Sanjay


    Alpha glucosidase inhibitors (AGIs) are a unique class of anti-diabetic drugs. Derived from bacteria, these oral drugs are enzyme inhibitors which do not have a pancreato -centred mechanism of action...

  3. Proton pump inhibitors (United States)

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by glands in ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This is a ...

  4. Zebrafish bioassay-guided natural product discovery: isolation of angiogenesis inhibitors from East African medicinal plants.

    Directory of Open Access Journals (Sweden)

    Alexander D Crawford

    Full Text Available Natural products represent a significant reservoir of unexplored chemical diversity for early-stage drug discovery. The identification of lead compounds of natural origin would benefit from therapeutically relevant bioassays capable of facilitating the isolation of bioactive molecules from multi-constituent extracts. Towards this end, we developed an in vivo bioassay-guided isolation approach for natural product discovery that combines bioactivity screening in zebrafish embryos with rapid fractionation by analytical thin-layer chromatography (TLC and initial structural elucidation by high-resolution electrospray mass spectrometry (HRESIMS. Bioactivity screening of East African medicinal plant extracts using fli-1:EGFP transgenic zebrafish embryos identified Oxygonum sinuatum and Plectranthus barbatus as inhibiting vascular development. Zebrafish bioassay-guided fractionation identified the active components of these plants as emodin, an inhibitor of the protein kinase CK2, and coleon A lactone, a rare abietane diterpenoid with no previously described bioactivity. Both emodin and coleon A lactone inhibited mammalian endothelial cell proliferation, migration, and tube formation in vitro, as well as angiogenesis in the chick chorioallantoic membrane (CAM assay. These results suggest that the combination of zebrafish bioassays with analytical chromatography methods is an effective strategy for the rapid identification of bioactive natural products.

  5. Zebrafish bioassay-guided natural product discovery: isolation of angiogenesis inhibitors from East African medicinal plants. (United States)

    Crawford, Alexander D; Liekens, Sandra; Kamuhabwa, Appolinary R; Maes, Jan; Munck, Sebastian; Busson, Roger; Rozenski, Jef; Esguerra, Camila V; de Witte, Peter A M


    Natural products represent a significant reservoir of unexplored chemical diversity for early-stage drug discovery. The identification of lead compounds of natural origin would benefit from therapeutically relevant bioassays capable of facilitating the isolation of bioactive molecules from multi-constituent extracts. Towards this end, we developed an in vivo bioassay-guided isolation approach for natural product discovery that combines bioactivity screening in zebrafish embryos with rapid fractionation by analytical thin-layer chromatography (TLC) and initial structural elucidation by high-resolution electrospray mass spectrometry (HRESIMS). Bioactivity screening of East African medicinal plant extracts using fli-1:EGFP transgenic zebrafish embryos identified Oxygonum sinuatum and Plectranthus barbatus as inhibiting vascular development. Zebrafish bioassay-guided fractionation identified the active components of these plants as emodin, an inhibitor of the protein kinase CK2, and coleon A lactone, a rare abietane diterpenoid with no previously described bioactivity. Both emodin and coleon A lactone inhibited mammalian endothelial cell proliferation, migration, and tube formation in vitro, as well as angiogenesis in the chick chorioallantoic membrane (CAM) assay. These results suggest that the combination of zebrafish bioassays with analytical chromatography methods is an effective strategy for the rapid identification of bioactive natural products.

  6. DPP-4 inhibitors

    DEFF Research Database (Denmark)

    Deacon, Carolyn F.


    Dipeptidyl peptidase (DPP)-4 inhibitors inhibit the activity of the enzyme responsible for the initial rapid degradation of the incretin hormones, thereby enhancing their antihyperglycemic effects.......Dipeptidyl peptidase (DPP)-4 inhibitors inhibit the activity of the enzyme responsible for the initial rapid degradation of the incretin hormones, thereby enhancing their antihyperglycemic effects....

  7. [Acquired coagulant factor inhibitors]. (United States)

    Nogami, Keiji


    Acquired coagulation factor inhibitors are an autoimmune disease causing bleeding symptoms due to decreases in the corresponding factor (s) which result from the appearance of autoantibodies against coagulation factors (inhibitor). This disease is quite different from congenital coagulation factor deficiencies based on genetic abnormalities. In recent years, cases with this disease have been increasing, and most have anti-factor VIII autoantibodies. The breakdown of the immune control mechanism is speculated to cause this disease since it is common in the elderly, but the pathology and pathogenesis are presently unclear. We herein describe the pathology and pathogenesis of factor VIII and factor V inhibitors. Characterization of these inhibitors leads to further analysis of the coagulation process and the activation mechanisms of clotting factors. In the future, with the development of new clotting examination method (s), we anticipate that further novel findings will be obtained in this field through inhibitor analysis. In addition, detailed elucidation of the coagulation inhibitory mechanism possibly leading to hemostatic treatment strategies for acquired coagulation factor disorders will be developed.

  8. Cathepsin D inhibitors

    Directory of Open Access Journals (Sweden)

    M. Gacko


    Full Text Available Inhibitors of cathepsin D belong to chemical compounds that estrify carboxyl groups of the Asp33 and Asp231residues of its catalytic site, penta-peptides containing statin, i.e. the amino acid similar in structure to the tetraedric indirectproduct, and polypeptides found in the spare organs of many plants and forming permanent noncovalent complexes withcathepsin. Cathepsin D activity is also inhibited by alpha2-macroglobulin and antibodies directed against this enzyme.Methods used to determine the activity and concentration of these inhibitors and their analytical, preparative and therapeuticapplications are discussed.

  9. Inhibitors of histone demethylases

    DEFF Research Database (Denmark)

    Lohse, Brian; Kristensen, Jesper L; Kristensen, Line H


    Methylated lysines are important epigenetic marks. The enzymes involved in demethylation have recently been discovered and found to be involved in cancer development and progression. Despite the relative recent discovery of these enzymes a number of inhibitors have already appeared. Most of the i...

  10. Protease inhibitors and beyond. (United States)


    A new generation of protease inhibitors is entering studies. Abbott Lab's ABT-378 and Pharmacia/Upjohn's PNU-140690 are beginning clinical studies and both are designed to overcome resistance problems. Several companies are developing new compounds to inhibit reverse transcriptase, such as Bristol-Myers Squibb's lobucavir and Hoechst/Bayer's HBY097. Calanolide A, which will soon begin trials, has a different resistance pattern than other non-nucleoside reverse transcriptase inhibitors, which may be an important advantage. Several groups are developing compounds to inhibit the HIV zinc finger, such as Parke-Davis' compound, CI-1012; and a Dutch company who is developing Azodicarbonamide, a drug currently in phase I/II trials for people with advanced disease in Europe. HIV drugs to date have not been successful in blocking viral fusion. However, three new fusion inhibitors are showing promise within the laboratory: Pentafuside (currently in phase I trials), Fuji ImmunoPharmaceuticals' FP-21399 (currently in phase I trials), and ISIS Pharmaceuticals' ISIS 5320. A new class of drugs known as integrase inhibitors has been of interest to pharmaceutical companies for the past several years; only one drug, Aronex Pharmaceuticals' Zintevir, has reached phase I/II trials.

  11. Transglutaminase inhibitor from milk

    NARCIS (Netherlands)

    Jong, G.A.H. de; Wijngaards, G.; Koppelman, S.J.


    Cross-linking experiments of skimmed bovine milk with bacterial transglutaminase isolated from Streptoverticillium mobaraense showed only some degree of formation of high-molecular-weight casein polymers. Studies on the nature of this phenomenon revealed that bovine milk contains an inhibitor of

  12. HIV protease inhibitor resistance

    NARCIS (Netherlands)

    Wensing, Annemarie M.J.; Fun, Axel; Nijhuis, Monique


    HIV protease is pivotal in the viral replication cycle and directs the formation of mature infectious virus particles. The development of highly specific HIV protease inhibitors (PIs), based on thorough understanding of the structure of HIV protease and its substrate, serves as a prime example of

  13. Phosphodiesterase 4 inhibitors. (United States)

    Zebda, Rema; Paller, Amy S


    Historically, drugs available for treating atopic dermatitis (AD) have been limited to topical corticosteroids and topical calcineurin inhibitors, with systemic immunosuppressants and phototherapy reserved for severe AD. Despite their efficacy and infrequent adverse events, phobia about the use of topical steroids and calcineurin inhibitors has limited their use. More targeted options with fewer systemic and cutaneous side effects are needed for treating AD. Phosphodiesterase 4 (PDE4) is involved in the regulation of proinflammatory cytokines via the degradation of cyclic adenosine monophosphate. PDE4 activity is increased in the inflammatory cells of patients with AD, leading to increased production of proinflammatory cytokines and chemokines. Targeting PDE4 reduces the production of these proinflammatory mediators in AD. Both topical and oral PDE4 inhibitors have a favorable safety profile. Crisaborole 2% ointment, a topical PDE4, is now US Food and Drug Administration-approved for children older than 2 years and adults in the treatment of AD. Crisaborole 2% ointment shows early and sustained improvement in disease severity and pruritus and other AD symptoms, with burning and/or stinging upon application as the only related adverse event. Other PDE4 inhibitors are currently in trials with promising efficacy and safety. Copyright © 2017. Published by Elsevier Inc.

  14. Proton-pump inhibitors

    African Journals Online (AJOL)

    Proton-pump inhibitors (PPIs) work by binding irreversibly to the. H+/K+-ATPase pump of the parietal cell, leading to inhibition of acid production in approximately 70% of active pumps.1The result is a dramatic increase in gastric pH mitigating the deleterious effects of acid in gastro-oesophageal reflux disease (GORD) and.

  15. Ck2-Dependent Phosphorylation Is Required to Maintain Pax7 Protein Levels in Proliferating Muscle Progenitors.

    Directory of Open Access Journals (Sweden)

    Natalia González

    Full Text Available Skeletal muscle regeneration and long term maintenance is directly link to the balance between self-renewal and differentiation of resident adult stem cells known as satellite cells. In turn, satellite cell fate is influenced by a functional interaction between the transcription factor Pax7 and members of the MyoD family of muscle regulatory factors. Thus, changes in the Pax7-to-MyoD protein ratio may act as a molecular rheostat fine-tuning acquisition of lineage identity while preventing precocious terminal differentiation. Pax7 is expressed in quiescent and proliferating satellite cells, while its levels decrease sharply in differentiating progenitors Pax7 is maintained in cells (reacquiring quiescence. While the mechanisms regulating Pax7 levels based on differentiation status are not well understood, we have recently described that Pax7 levels are directly regulated by the ubiquitin-ligase Nedd4, thus promoting proteasome-dependent Pax7 degradation in differentiating satellite cells. Here we show that Pax7 levels are maintained in proliferating muscle progenitors by a mechanism involving casein kinase 2-dependent Pax7 phosphorylation at S201. Point mutations preventing S201 phosphorylation or casein kinase 2 inhibition result in decreased Pax7 protein in proliferating muscle progenitors. Accordingly, this correlates directly with increased Pax7 ubiquitination. Finally, Pax7 down regulation induced by casein kinase 2 inhibition results in precocious myogenic induction, indicating early commitment to terminal differentiation. These observations highlight the critical role of post translational regulation of Pax7 as a molecular switch controlling muscle progenitor fate.

  16. Ability of CK2beta to selectively regulate cellular protein kinases

    DEFF Research Database (Denmark)

    Olsen, Birgitte; Guerra, Barbara


    The Wee1 protein kinase plays a prominent role in keeping cyclin dependent kinase 1 (CDK1) inactive during the G2 phase of the cell cycle. At the onset of mitosis, Wee1 is ubiquitinated by the E3 ubiquitin ligase SCF(beta-TrCP) and subsequently degraded by the proteasome machinery. Previously, it...

  17. Protein kinase CK2 and its role in cellular proliferation, development and pathology

    DEFF Research Database (Denmark)

    Guerra, B; Issinger, O G


    , signaling, proliferation and in various steps of development. The tetrameric holoenzyme (alpha2beta2) consists of two catalytic alpha-subunits and two regulatory beta-subunits. The structure of the catalytic subunit with the fixed positioning of the activation segment in the active conformation through its...

  18. [Cytoplasmic kinase inhibitors]. (United States)

    Mano, Hiroyuki


    Protein kinases play essential roles in the regulation of cell proliferation. Point mutations or/and fusions of protein kinases are frequently identified in human cancers, and targeting such activated kinases provides us with a chance to eradicate tumor cells. This was first proved by imatinib mesylate that inhibits ABL tyrosine kinase and, thereby, efficiently kills malignant cells in chronic myeloid leukemia. In addition, other clinical trials are ongoing for kinase inhibitors against EML4--ALK in lung cancer, JAK2 in myeloproliferative disorders and BRAF in malignant melanoma. Early reports indeed reveal that such targeting compounds are promising drugs for human cancers with activated kinases.

  19. Methyl Jasmonate Induces Papain Inhibitor(s) in Tomato Leaves. (United States)

    Bolter, C. J.


    Leaves of 18- to 24-d-old tomato (Lycopersicon esculentum) plants exposed to gaseous methyl jasmonate (MJ) for 24 h at 30[deg]C in continuous light contained high levels of soluble protein that inhibited papain. Chromatographic analysis demonstrated that the active protein had a molecular mass of 80 to 90 kD. Induction of papain inhibitor was directly related to the concentration of air-borne MJ up to a maximum of 0.1 [mu]L MJ per treatment and depended on the duration of exposure up to 18 h. Inhibitor activity in plants treated for less than 18 h increased with time after treatment. Levels remained constant for up to 4 d after treatment, after which time activity decreased. The youngest leaf, leaf 5, consistently lost activity at a faster rate than older, lower leaves. Inhibitor concentration in all leaves was reduced to minimum levels by 11 d after MJ treatment, but did not return to control levels. Treatment with MJ in the dark did induce inhibitor activity, but at a significantly lower rate. Polyclonal antibodies raised to purified potato tuber skin cysteine proteinase inhibitors (CPI) cross-reacted with the tomato inhibitor, suggesting that the tomato papain inhibitor and the potato CPI are closely related. No papain inhibitor activity was observed in extracts from wounded tomato leaves, nor was there any immunoreactivity with antibodies raised to potato tuber skin CPI.

  20. Inhibition of cholinergic potentiation of insulin secretion from pancreatic islets by chronic elevation of glucose and fatty acids: Protection by casein kinase 2 inhibitor

    Directory of Open Access Journals (Sweden)

    Nicolai M. Doliba


    Conclusions: These results show that chronic FA treatment decreases acetylcholine potentiation of insulin secretion and that this effect is strictly glucose dependent and might involve CK2 phosphorylation of β-cell M3 muscarinic receptors.

  1. Proteinase inhibitors in Brazilian leguminosae

    Directory of Open Access Journals (Sweden)

    C. A. M. Sampaio


    Full Text Available Serine proteinase inhitors, in the seeds of several Leguminosae from the Pantanal region (West Brazil, were studied using bovine trypsin, a digestive enzyme, Factor XIIa and human plasma Kallikrein, two blood clotting factors. The inhibitors were purified from Enterolobium contortisiliquum (Mr=23,000, Torresea cearensis (Mr = 13,000, Bauhinia pentandra (Mr = 20,000 and Bauhinia bauhinioides (Mr = 20,000. E. contortisiliquum inhibitor inactivates all three enzymes, whereas the T. cearensis inhibitor inactivates trypsin and Factor XSSa, but does nor affect plasma kallikrein; both Bauhinia inhibitors, on the other hand, inactivate trypsin and plasma kallikrein but only the Bpentandra inhibitor affects Factor XIIa. Ki values were calculated between 10 [raised to the power of] -7 and 10 [raised to the power of] -8 M.

  2. [Progress on matrix metalloproteinase inhibitors]. (United States)

    Lingling, Jia; Qianbing, Wan


    Continuing advances in dentin bonding technology and adhesives revolutionized bonding of resin-based composite restorations. However, hybrid layers created by contemporary dentin adhesives present imperfect durability, and degradation of collagen matrix by endogenous enzymes is a significant factor causing destruction of hybrid layers. Bond durability can be improved by using enzyme inhibitors to prevent collagen degradation and to preserve integrity of collagen matrix. This review summarizes progress on matrix metalloproteinase inhibitors (including chlorhexidine, ethylenediaminetetraacetic acid, quaternary ammonium salt, tetracycline and its derivatives, hydroxamic acid inhibitors, bisphosphonate derivative, and cross-linking agents) and suggests prospects for these compounds.

  3. Angiogenesis Inhibitors in NSCLC

    Directory of Open Access Journals (Sweden)

    Anna Manzo


    Full Text Available Angiogenesis is a complex biological process that plays a relevant role in sustaining the microenvironment, growth, and metastatic potential of several tumors, including non-small cell lung cancer (NSCLC. Bevacizumab was the first angiogenesis inhibitor approved for the treatment of patients with advanced NSCLC in combination with chemotherapy; however, it was limited to patients with non-squamous histology and first-line setting. Approval was based on the results of two phase III trials (ECOG4599 and AVAIL that demonstrated an improvement of about two months in progression-free survival (PFS in both trials, and in the ECOG4599 trial, an improvement in overall survival (OS also. Afterwards, other antiangiogenic agents, including sunitinib, sorafenib, and vandetanib have been unsuccessfully tested in first and successive lines. Recently, two new antiangiogenic agents (ramucirumab and nintedanib produced a significant survival benefit in second-line setting. In the REVEL study, ramucirumab plus docetaxel prolonged the median OS of patients with any histology NSCLC when compared with docetaxel alone (10.4 versus 9.1 months, hazard ratio (HR 0.857, p = 0.0235. In the LUME-Lung 1 study, nintedanib plus docetaxel prolonged the median PFS of patients with any tumor histology (p = 0.0019, and improved OS (12.6 versus 10.3 months in patients with adenocarcinoma. As a result, it became a new option for the second-line treatment of patients with advanced NSCLC and adenocarcinoma histology. Identifying predictive biomarkers to optimize the benefit of antiangiogenic drugs remains an ongoing challenge.

  4. Thrombin inhibitors from different animals. (United States)

    Tanaka-Azevedo, A M; Morais-Zani, K; Torquato, R J S; Tanaka, A S


    Venous and arterial thromboembolic diseases are still the most frequent causes of death and disability in high-income countries. Clinical anticoagulants are inhibitors of enzymes involved in the coagulation pathway, such as thrombin and factor X(a). Thrombin is a key enzyme of blood coagulation system, activating the platelets, converting the fibrinogen to the fibrin net, and amplifying its self-generation by the activation of factors V, VIII, and XI. Thrombin has long been a target for the development of oral anticoagulants. Furthermore, selective inhibitors of thrombin represent a new class of antithrombotic agents. For these reasons, a number of specific thrombin inhibitors are under evaluation for possible use as antithrombotic drugs. This paper summarizes old and new interests of specific thrombin inhibitors described in different animals.

  5. Thrombin Inhibitors from Different Animals

    Directory of Open Access Journals (Sweden)

    A. M. Tanaka-Azevedo


    Full Text Available Venous and arterial thromboembolic diseases are still the most frequent causes of death and disability in high-income countries. Clinical anticoagulants are inhibitors of enzymes involved in the coagulation pathway, such as thrombin and factor Xa. Thrombin is a key enzyme of blood coagulation system, activating the platelets, converting the fibrinogen to the fibrin net, and amplifying its self-generation by the activation of factors V, VIII, and XI. Thrombin has long been a target for the development of oral anticoagulants. Furthermore, selective inhibitors of thrombin represent a new class of antithrombotic agents. For these reasons, a number of specific thrombin inhibitors are under evaluation for possible use as antithrombotic drugs. This paper summarizes old and new interests of specific thrombin inhibitors described in different animals.

  6. Selective Serotonin Reuptake Inhibitors (SSRIs) (United States)

    ... Selective serotonin reuptake inhibitors: Pharmacology, administration, and side effects. Accessed June 2, 2016. Mental health medications. National Institute of Mental Health. http://www. ...

  7. Formulary management of ACE inhibitors. (United States)

    Gerbrandt, K R; Yedinak, K C


    An increasing number of ACE inhibitors have become available in recent years. Because these agents are all similar, careful scrutiny is required in order to determine specific advantages of particular agents when making formulary decisions. Differences between agents with regard to structure and tissue specificity have been identified, but the clinical relevance of these differences is not clear. ACE inhibitors vary greatly with regard to bioconversion, distribution and elimination. Disease states such as congestive heart failure (CHF) and hepatic or renal insufficiency may affect the disposition of specific ACE inhibitors. These agents may differ substantially in duration of action, and ACE inhibitors that are given once daily may optimise patient compliance and decrease costs. ACE inhibitors have been extensively studied in patients with hypertension, CHF or nephropathy, and following myocardial infarction (MI). Differences in efficacy between agents are often a result of variations in study design, or because nonequipotent dosages were compared. It is likely that the benefits of ACE inhibitors are class effects, and it is probably reasonable to use an agent even if large scale clinical trials have not been performed with that particular drug. Few differences have been found between ACE inhibitors with regard to adverse effects or drug interactions, and these factors are of minor importance when making formulary decisions. Cost and availability may vary among agents, and will depend on geographical location and institution-specific purchasing contracts. ACE inhibitors have shown positive effects on quality of life when compared with agents of other classes. Quality-of-life studies that have directly compared ACE inhibitors have produced conflicting results. In the setting of hypertension, cost-effectiveness evaluations typically find that the newer, longer-acting ACE inhibitors provide the greatest financial benefit. Differences in cost effectiveness in the post

  8. Positron emitter labeled enzyme inhibitors (United States)

    Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.


    This invention involved a new strategy for imaging and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide in activators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography. 2 figs.


    Directory of Open Access Journals (Sweden)

    O. V. Matseliukh


    Full Text Available In a review the literature data on protein inhibitors of peptidases synthesised by different types of microorganisms are systematized. It is shown that at the present time on the basis of amino acid sequence homology protein inhibitors are grouped into 77 families, 29 of which include inhibitors of microorganisms. The mechanism of inhibition of peptidases by proteins may be related to their catalytic mechanism of action or include unrelated blocking of the active site or its surroundings. The structural elements of the protein inhibitors are responsible for binding to the peptidases, mostly include the N- or C-terminal sequences, the unprotected polypeptide loops (chains, which are acting independently or in combination with other elements. The basic properties, structural features and, where it is established, the functions of the protein inhibitors of peptidases are considered. Since some of these proteins effectively inhibit such peptidases as subtilisin, chymotrypsin, pancreatic elastase, their practical use in the treatment of diseases such as emphysema, arthritis, pancreatitis, thrombosis, hypertension, muscular dystrophy, cancer. It is suggested that the role of a bacterial homologue of Escherichia coli alphaacroglobulin, which is a periplasmic protein, is to protect the periplasmic space from the action of bacteria own proteases. Based on the specific properties of alpha-2-macroglobulin to bind endopeptidases active molecules, they are used in biotechnology to isolate endopeptidases from crude biological preparations and titration of its active centers. Some free–living bacteria are able to synthesize protein inhibitors to protect from the effects of its own enzymes, while the presence of these proteins in pathogens may play a certain role both in the infectious process and in the protection of the host proteases.

  10. Proton pump inhibitors and gastroenteritis

    NARCIS (Netherlands)

    R.J. Hassing (Robert); A. Verbon (Annelies); H. de Visser (Herman); A. Hofman (Albert); B.H.Ch. Stricker (Bruno)


    textabstractAn association between proton pump inhibitor (PPI) therapy and bacterial gastroenteritis has been suggested as well as contradicted. The aim of this study was to examine the association between the use of PPIs and occurrence of bacterial gastroenteritis in the prospective Rotterdam

  11. Nicotinamide phosphoribosyltransferase inhibitors, design, preparation and SAR

    DEFF Research Database (Denmark)

    Christensen, Mette Knak; Erichsen, Kamille Dumong; Olesen, Uffe Hogh


    Existing pharmacological inhibitors for nicotinamide phosphoribosyltransferase (NAMPT) are promising therapeutics for treating cancer. Using medicinal and computational chemistry methods, the structure-activity relationship for novel classes of NAMPT inhibitors is described and compounds optimize...

  12. Allosteric small-molecule kinase inhibitors

    DEFF Research Database (Denmark)

    Wu, Peng; Clausen, Mads Hartvig; Nielsen, Thomas E.


    current barriers of kinase inhibitors, including poor selectivity and emergence of drug resistance. In spite of the small number of identified allosteric inhibitors in comparison with that of inhibitors targeting the ATP pocket, encouraging results, such as the FDA-approval of the first small...

  13. Electrochemiluminescence resonance energy transfer between graphene quantum dots and graphene oxide for sensitive protein kinase activity and inhibitor sensing

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Ru-Ping; Qiu, Wei-Bin; Zhao, Hui-Fang; Xiang, Cai-Yun; Qiu, Jian-Ding, E-mail:


    Herein, a novel electrochemiluminescence resonance energy transfer (ECL-RET) biosensor using graphene quantum dots (GQDs) as donor and graphene oxide (GO) as acceptor for monitoring the activity of protein kinase was presented for the first time. Anti-phosphoserine antibody conjugated graphene oxide (Ab-GO) nonocomposite could be captured onto the phosphorylated peptide/GQDs modified electrode surface through antibody–antigen interaction in the presence of casein kinase II (CK2) and adenosine 5′-triphosphate (ATP), resulting in ECL from the GQDs quenching by closely contacting GO. This ECL quenching degree was positively correlated with CK2 activity. Therefore, on the basis of ECL-RET between GQDs and GO, the activity of protein kinase can be detected sensitively. This biosensor can also be used for quantitative analysis CK2 activity in serum samples and qualitative screening kinase inhibition, indicating the potential application of the developed method in biochemical fundamental research and clinical diagnosis. - Highlights: • We reported a novel ECL-RET biosensor for sensitive analysis of casein kinase II activity. • The successful ECL-RET between GQDs and GO could be established. • GQDs was employed for casein kinase II activity monitoring and inhibition assay. • Highly sensitive detection of CK2 activity and inhibition was achieved.

  14. Proteasome inhibitors with photocontrolled activity. (United States)

    Hansen, Mickel J; Velema, Willem A; de Bruin, Gerjan; Overkleeft, Herman S; Szymanski, Wiktor; Feringa, Ben L


    Proteasome inhibitors are widely used in cancer treatment as chemotherapeutic agents. However, their employment often results in severe side effects, due to their non-specific cytotoxicity towards healthy tissue. This problem might be overcome by using a photopharmacological approach, that is, by attaining external, dynamic, spatiotemporal photocontrol over the activity of a cytotoxic agent, achieved by the introduction of a photoswitchable moiety into its molecular structure. Here we describe the design, synthesis, and activity of photoswitchable proteasome inhibitors. Substantial differences in proteasome inhibitory activity in cell extracts were observed before and after irradiation with light. The presented results show potential for the development of chemotherapeutic agents that can be switched on and off with light, constituting a new strategy for spatiotemporally modulating proteasomal activity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Small-molecule arginase inhibitors. (United States)

    Ivanenkov, Yan A; Chufarova, Nina V


    Arginase is an enzyme that metabolizes L-arginine to L-ornithine and urea. In addition to its fundamental role in the hepatic ornithine cycle, it also influences the immune systems in humans and mice. Arginase participates in many inflammatory disorders by decreasing the synthesis of nitric oxide and inducing fibrosis and tissue regeneration. L-arginine deficiency, which is modulated by myeloid cell arginase, suppresses T-cell immune response. This mechanism plays a fundamental role in inflammation-associated immunosuppression. Pathogens can synthesize their own arginase to elude immune reaction. Small-molecule arginase inhibitors are currently described as promising therapeutics for the treatment of several diseases, including allergic asthma, inflammatory bowel disease, ulcerative colitis, cardiovascular diseases (atherosclerosis and hypertension), diseases associated with pathogens (e.g., Helicobacter pylori, Trypanosoma cruzi, Leishmania, Mycobacterium tuberculosis and Salmonella), cancer and induced or spontaneous immune disorders. This article summarizes recent patents in the area of arginase inhibitors and discusses their properties.

  16. Proteasome inhibitors in cancer therapy

    Directory of Open Access Journals (Sweden)

    Wioletta Romaniuk


    Full Text Available Proteasomes are multisubunit enzyme complexes. They contain three enzymatic active sites which are termed chymotrypsin-like, trypsin-like, and caspase-like. The elementary function of the proteasomes is degradation of damaged proteins. Proteasome inhibition leads to accumulation of damaged protein, which leads to caspase activation and cell death. This relationship is used in cancer therapy. Bortezomib is the first proteasome inhibitor approved by the US Food and Drug Administration for the treatment of relapsed/refractory multiple myeloma. Carfilzomib belongs to the second generation of drugs, which was approved by the US FDA in 2012. Currently in the study phase there are four new inhibitors: ixazomib (MLN9780/MLN2238, delanzomib (CEP-18770, oprozomib (ONX0912/PR-047 and marizomib (NPI-0052.

  17. Natural Inhibitors of Maillard Browning (United States)


    incorporated into pre-selected candidate ration components for evaluation via storage, sensory and chemical analysis. The concentration of inhibitor was...inhibiting Maillard browning, also known as non-enzymatic browning, a complex reaction which can lead to darkening of color, off- odors , off-flavors...nutritional intake, and decrease waste due to non-consumption of sensory degraded ration components. 1.1 Maillard Browning Maillard browning, also

  18. Proton Pump Inhibitors and Gastritis


    Suzuki, Masayuki; Suzuki, Hidekazu; Hibi, Toshifumi


    Proton pump inhibitors (PPIs) are novel compounds that strongly inhibit the H+/K+-ATPase in the gastric parietal cells to cause profound suppression of acid secretion. Acid-generating ATPase, also known as vacuolar-type ATPase, is located in the lysozomes of leukocytes and osteoclasts and its activity is also reportedly influenced by treatment with PPIs. This concept is supported by the results of studies using autoradiography in which 3H-Lansoprazole uptake sites were clearly detected in the...

  19. Stabilization versus inhibition of TAFIa by competitive inhibitors in vitro

    NARCIS (Netherlands)

    Walker, J.B.; Hughes, B.; James, I.; Haddock, P.; Kluft, C.; Bajzar, L.


    Two competitive inhibitors of TAFIa (activated thrombin-activable fibrinolysis inhibitor), 2-guanidinoethyl-mercaptosuccinic acid and potato tuber carboxypeptidase inhibitor, variably affect fibrinolysis of clotted human plasma. Depending on their concentration, the inhibitors shortened, prolonged,

  20. Emerging therapies for atopic dermatitis: JAK inhibitors. (United States)

    Cotter, David G; Schairer, David; Eichenfield, Lawrence


    The Janus kinase-signal transducer and activator of transcription pathway is a conserved master regulator of immunity and myeloproliferation. Advanced understanding of this pathway has led to development of targeted inhibitors of Janus kinases (Jakinibs). As a class, JAK inhibitors effectively treat a multitude of hematologic and inflammatory diseases. Given such success, use of JAK inhibitors for mitigation of atopic dermatitis is under active investigation. Herein, we review the evolving data on the safety and efficacy of JAK inhibitors in treatment of atopic dermatitis. Although it is still early in the study of JAK inhibitors for atopic dermatitis, evidence identifies JAK inhibitors as effective alternatives to conventional therapies. Nonetheless, multiple large safety and efficacy trials are needed before widespread use of JAK inhibitors can be advocated for atopic dermatitis. Copyright © 2017. Published by Elsevier Inc.

  1. Targeting telomerase with radiolabeled inhibitors. (United States)

    Waghorn, Philip A; Jackson, Mark R; Gouverneur, Veronique; Vallis, Katherine A


    The expression of telomerase in approximately 85% of cancers and its absence in the majority of normal cells makes it an attractive target for cancer therapy. However the lag period between initiation of telomerase inhibition and growth arrest makes direct inhibition alone an insufficient method of treatment. However, telomerase inhibition has been shown to enhance cancer cell radiosensitivity. To investigate the strategy of simultaneously inhibiting telomerase while delivering targeted radionuclide therapy to cancer cells, 123 I-radiolabeled inhibitors of telomerase were synthesized and their effects on cancer cell survival studied. An 123 I-labeled analogue of the telomerase inhibitor MST-312 inhibited telomerase with an IC 50 of 1.58 μM (MST-312 IC 50 : 0.23 μM). Clonogenic assays showed a dose dependant effect of 123 I-MST-312 on cell survival in a telomerase positive cell line, MDA-MB-435. Copyright © 2016 The Authors. Published by Elsevier Masson SAS.. All rights reserved.

  2. Vanadium Compounds as PTP Inhibitors

    Directory of Open Access Journals (Sweden)

    Elsa Irving


    Full Text Available Phosphotyrosine signaling is regulated by the opposing actions of protein tyrosine kinases (PTKs and protein tyrosine phosphatases (PTPs. Here we discuss the potential of vanadium derivatives as PTP enzyme inhibitors and metallotherapeutics. We describe how vanadate in the V oxidized state is thought to inhibit PTPs, thus acting as a pan-inhibitor of this enzyme superfamily. We discuss recent developments in the biological and biochemical actions of more complex vanadium derivatives, including decavanadate and in particular the growing number of oxidovanadium compounds with organic ligands. Pre-clinical studies involving these compounds are discussed in the anti-diabetic and anti-cancer contexts. Although in many cases PTP inhibition has been implicated, it is also clear that many such compounds have further biochemical effects in cells. There also remain concerns surrounding off-target toxicities and long-term use of vanadium compounds in vivo in humans, hindering their progress through clinical trials. Despite these current misgivings, interest in these chemicals continues and many believe they could still have therapeutic potential. If so, we argue that this field would benefit from greater focus on improving the delivery and tissue targeting of vanadium compounds in order to minimize off-target toxicities. This may then harness their full therapeutic potential.

  3. Proteasome inhibitor patents (2010 - present). (United States)

    Metcalf, Rainer; Scott, Latanya M; Daniel, Kenyon G; Dou, Q Ping


    Over the past 3 years, numerous patents and patent applications have been submitted and published involving compounds designed to inhibit the proteasome. Proteasome inhibition has been of great interest in cancer research since disruption of proteolysis leads to a significant buildup of cytotoxic proteins and activation of apoptotic pathways, particularly in rapidly proliferating cells. The current standards in proteasome inhibition are the only FDA-approved inhibitors, bortezomib and carfilzomib. Although these drugs are quite effective in treating multiple myeloma and other blood tumors, there are shortcomings, including toxicities and resistance. Most of the current patents attempt to improve on existing compounds, by increasing bioavailability and selectivity, while attempting to reduce toxicity. A general categorization of similar compounds was employed to evaluate and compare drug design strategies. This review focuses on novel compounds and subsequent analogs developed for proteasome inhibition, used in preventing and treating human cancers. A comprehensive description and categorization of patents related to each type of compound and its derivatives, as well as their uses and efficacies as anticancer agents is included. A review of combination therapy patents has also been included. Although there are many diverse chemical scaffolds being published, there are few patented proteasome inhibitors whose method of inhibition is genuinely novel. Most patents utilize a destructive chemical warhead to attack the catalytic threonine residue of the proteasome active sites. Few patents try to depart from this, emphasizing the need for developing new mechanisms of action and specific targeting.

  4. Proton pump inhibitors and osteoporosis

    DEFF Research Database (Denmark)

    Andersen, Bjarne Nesgaard; Johansen, Per Birger; Abrahamsen, Bo


    PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months and a di......PURPOSE OF REVIEW: The purpose of the review is to provide an update on recent advances in the evidence based on proton pump inhibitors (PPI) as a possible cause of osteoporosis and osteoporotic fractures. This review focuses, in particular, on new studies published in the last 18 months...... and a discussion of these findings and how this has influenced our understanding of this association, the clinical impact and the underlying pathophysiology. RECENT FINDINGS: New studies have further strengthened existing evidence linking use of PPIs to osteoporosis. Short-term use does not appear to pose a lower...... risk than long-term use. There is a continued lack of conclusive studies identifying the pathogenesis. Direct effects on calcium absorption or on osteoblast or osteoclast action cannot at present plausibly explain the mechanism. SUMMARY: The use of PPIs is a risk factor for development of osteoporosis...

  5. Laura: Soybean variety lacking Kunitz trypsin inhibitor

    Directory of Open Access Journals (Sweden)

    Srebrić Mirjana


    Full Text Available Grain of conventional soybean varieties requires heat processing to break down trypsin inhibitor's activity before using as food or animal feed. At the same time, protein denaturation and other qualitative changes occur in soybean grain, especially if the temperature of heating is not controlled. Two types of trypsin inhibitor were found in soybean grain the Kunitz trypsin inhibitor and the Bowman-Birk inhibitor. Mature grain of soybean Laura is lacking Kunitz trypsin inhibitor. Grain yield of variety Laura is equal to high yielding varieties from the maturity group I, where it belongs. Lacking of Kunitz-trypsin inhibitor makes soybean grain suitable for direct feeding in adult non ruminant animals without previous thermal processing. Grain of variety Laura can be processed for a shorter period of time than conventional soybeans. This way we save energy, and preserve valuable nutritional composition of soybean grain, which is of interest in industrial processing.

  6. An inhibitor of phospholipase D in saliva (United States)

    Dawson, Rex M. C.; Hemington, Norma


    1. Bovine, dog and human saliva contain substances which inhibit the soluble phospholipase D present in grass leaf or celery stalk. 2. The inhibitor in bovine saliva is of high molecular weight and exhibits considerable stability to heat, acids and alkalis. 3. The inhibitor has been purified free from salivary mucoprotein. 4. It is suggested that the inhibitor could protect the upper alimentary tract of a herbage-eating animal from the necrotic action of phospholipase D. PMID:4376946

  7. Casein kinase 2 associates with initiation-competent RNA polymerase I and has multiple roles in ribosomal DNA transcription. (United States)

    Panova, Tatiana B; Panov, Kostya I; Russell, Jackie; Zomerdijk, Joost C B M


    Mammalian RNA polymerase I (Pol I) complexes contain a number of associated factors, some with undefined regulatory roles in transcription. We demonstrate that casein kinase 2 (CK2) in human cells is associated specifically only with the initiation-competent Pol Ibeta isoform and not with Pol Ialpha. Chromatin immunoprecipitation analysis places CK2 at the ribosomal DNA (rDNA) promoter in vivo. Pol Ibeta-associated CK2 can phosphorylate topoisomerase IIalpha in Pol Ibeta, activator upstream binding factor (UBF), and selectivity factor 1 (SL1) subunit TAFI110. A potent and selective CK2 inhibitor, 3,8-dibromo-7-hydroxy-4-methylchromen-2-one, limits in vitro transcription to a single round, suggesting a role for CK2 in reinitiation. Phosphorylation of UBF by CK2 increases SL1-dependent stabilization of UBF at the rDNA promoter, providing a molecular mechanism for the stimulatory effect of CK2 on UBF activation of transcription. These positive effects of CK2 in Pol I transcription contrast to that wrought by CK2 phosphorylation of TAFI110, which prevents SL1 binding to rDNA, thereby abrogating the ability of SL1 to nucleate preinitiation complex (PIC) formation. Thus, CK2 has the potential to regulate Pol I transcription at multiple levels, in PIC formation, activation, and reinitiation of transcription.

  8. Histone deacetylase inhibitors in cancer therapy. (United States)

    Lane, Andrew A; Chabner, Bruce A


    Epigenetic processes are implicated in cancer causation and progression. The acetylation status of histones regulates access of transcription factors to DNA and influences levels of gene expression. Histone deacetylase (HDAC) activity diminishes acetylation of histones, causing compaction of the DNA/histone complex. This compaction blocks gene transcription and inhibits differentiation, providing a rationale for developing HDAC inhibitors. In this review, we explore the biology of the HDAC enzymes, summarize the pharmacologic properties of HDAC inhibitors, and examine results of selected clinical trials. We consider the potential of these inhibitors in combination therapy with targeted drugs and with cytotoxic chemotherapy. HDAC inhibitors promote growth arrest, differentiation, and apoptosis of tumor cells, with minimal effects on normal tissue. In addition to decompaction of the histone/DNA complex, HDAC inhibition also affects acetylation status and function of nonhistone proteins. HDAC inhibitors have demonstrated antitumor activity in clinical trials, and one drug of this class, vorinostat, is US Food and Drug Administration approved for the treatment of cutaneous T-cell lymphoma. Other inhibitors in advanced stages of clinical development, including depsipeptide and MGCD0103, differ from vorinostat in structure and isoenzyme specificity, and have shown activity against lymphoma, leukemia, and solid tumors. Promising preclinical activity in combination with cytotoxics, inhibitors of heat shock protein 90, and inhibitors of proteasome function have led to combination therapy trials. HDAC inhibitors are an important emerging therapy with single-agent activity against multiple cancers, and have significant potential in combination use.

  9. [Development of new antiatherosclerotic agents--ACAT inhibitors and CETP inhibitors]. (United States)

    Miyazaki, A; Horiuchi, S


    Development of new antiatherosclerotic agents were reviewed focusing on ACAT inhibitors and CETP inhibitors. ACAT inhibitors enhance intracellular degradation of VLDL in hepatocytes. Cholesterol absorption in small intestine is inhibited by ACAT inhibitors. Thus, ACAT inhibitors reduce plasma cholesterol levels. In atherosclerotic lesions, ACAT inhibitors suppress foam cell formation (cholesteryl ester accumulation) in macrophages. Since ACAT inhibitors have multiple anti-atherogenic effects, they are considered future drugs controlling hypercholesterolemia and atherosclerosis. CETP inhibitors are expected to increase HDL and decrease LDL. Although the patients with CETP deficiency show high level of HDL, recent studies showed that they are not necessarily resistant to atherosclerosis. The strategy to inhibit CETP for suppressing atherosclerosis has not been established.

  10. Development of immune checkpoint inhibitors. (United States)

    Kitano, Shigehisa


    Immune checkpoint inhibitors are the most striking innovation in the clinical development of immunotherapy. Monoclonal antibodies (mAbs) restore and augment the antitumor immune activities of cytotoxic T cells by mainly blocking immune checkpoint molecules on T cells or their ligands on antigen-presenting and tumor cells. Based on preclinical data, many clinical trials have demonstrated the acceptable safety profiles and efficacies of mAb in various cancers. The A first-in-class approved immune checkpoint inhibitor is ipilimumab, which is a fully humanized mAb that blocks the immunosuppressive signal by cytotoxic T-lymphocyte antigen 4. In 2011, the US Food and Drug Administration approved the use of ipilimumab for the treatment of advanced metastatic melanoma. Then, nivolumab, which is a humanized mAb that blocks programmed death-1 (PD-1), was approved for use in the treatment of advanced melanoma in 2014 and of advanced non-small-cell lung carcinoma (NSCLC) in 2015 in Japan. Pembrolizumab, which is another anti-PD-1 antibody, was approved for use in the treatment of advanced melanoma and advanced NSCLC as the first-line therapy in 2016 in Japan. Thereafter, nivolumab was also approved for use in the treatment of advanced renal cell cancer in August 2016, of Hodgkin's lymphoma in December 2016, and of head and neck cancer in March 2017 in Japan. Moreover, phase III trials of anti-PD-1 mAb and anti-PD-ligand 1 mAb for use in the treatment of cancers, such as gastric, ovarian, bladder, and esophageal cancers, are ongoing. Several clinical trials have investigated new agents, alone and in combination, for use in the treatment of various cancers. Current advances in tumor immunology have unveiled the importance of immunosuppressive cells, such as regulatory T cells, myeloid-derived suppressor cells, and tumor-associated macrophages, especially in a tumor microenvironment (TME). Some data from basic research in mouse models and the immunomonitoring of cancer patients

  11. Calcineurin inhibitor minimisation versus continuation of calcineurin inhibitor treatment for liver transplant recipients

    DEFF Research Database (Denmark)

    Penninga, Luit; Wettergren, Andre; Chan, An-Wen


    The therapeutic success of liver transplantation has been largely attributable to the development of effective immunosuppressive treatment regimens. In particular, calcineurin inhibitors were essential in reducing acute rejection and improving early survival. Currently, more than 90% of all liver...... transplant recipients are treated with the calcineurin inhibitor cyclosporine or tacrolimus. Unfortunately, calcineurin inhibitors cause adverse events, such as nephrotoxicity, and because of this, minimisation (reduction and withdrawal) regimens of calcineurin inhibitor have been developed and studied...

  12. Integrin Inhibitors in Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Maylein C. Juan-Rivera


    Full Text Available Prostate cancer (PCa is the most frequently diagnosed cancer and the third highest cause of cancer-related deaths in men in the U.S. The development of chemotherapeutic agents that can bind PCa tumor cells with high specificity is critical in order to increase treatment effectiveness. Integrin receptors and their corresponding ligands have different expression patterns in PCa cells. They have been identified as promising targets to inhibit pathways involved in PCa progression. Currently, several compounds have proven to target specific integrins and their subunits in PCa cells. In this article, we review the role of integrins inhibitors in PCa and their potential as therapeutic targets for PCa treatments. We have discussed the following: natural compounds, monoclonal antibodies, statins, campothecins analog, aptamers, d-aminoacid, and snake venom. Recent studies have shown that their mechanisms of action result in decrease cell migration, cell invasion, cell proliferation, and metastasis of PCa cells.

  13. Protein C inhibitor (plasminogen activator inhibitor-3) and the risk of venous thrombosis

    NARCIS (Netherlands)

    Meijers, JCM; Marquart, JA; Bertina, RM; Rosendaal, FR; Bouma, Bonno N.

    Protein C inhibitor (PCI), also known as plasminogen activator inhibitor-3, is a serine proteinase inhibitor that can inhibit enzymes in blood coagulation, fibrinolysis and fertility. The role of PCI in regulating the blood coagulation mechanism is not known, as it can inhibit both procoagulant

  14. Intellectual property issues of immune checkpoint inhibitors. (United States)

    Storz, Ulrich


    Immune checkpoint inhibitors are drugs that interfere with tumor escape responses. Some members of this class are already approved, and expected to be blockbusters in the future. Many companies have developed patent activities in this field. This article focuses on the patent landscape, and discusses key players and cases related to immune checkpoint inhibitors.

  15. A cyclic peptidic serine protease inhibitor

    DEFF Research Database (Denmark)

    Zhao, Baoyu; Xu, Peng; Jiang, Longguang


    Peptides are attracting increasing interest as protease inhibitors. Here, we demonstrate a new inhibitory mechanism and a new type of exosite interactions for a phage-displayed peptide library-derived competitive inhibitor, mupain-1 (CPAYSRYLDC), of the serine protease murine urokinase...

  16. [Interaction between clopidogrel and proton pump inhibitors

    NARCIS (Netherlands)

    Harmsze, A.M.; Boer, A. de; Boot, H.; Deneer, V.H.; Heringa, M.; Mol, P.G.; Schalekamp, T.; Verduijn, M.M.; Verheugt, F.W.A.; Comte, M. le


    The drug interaction between proton pump inhibitors and clopidogrel has been the subject of much study in recent years. Contradictory results regarding the effect of proton pump inhibitors on platelet reactivity and on clinical outcome in clopidogrel-treated patients have been reported in

  17. Potential physiological role of plant glycosidase inhibitors

    DEFF Research Database (Denmark)

    Bellincampi, D.; Carmadella, L.; Delcour, J.A.


    Carbohydrate-active enzymes including glycosidases, transglycosidases, glycosyltransferases, polysaccharide lyases and carbohydrate esterases are responsible for the enzymatic processing of carbohydrates in plants. A number of carbohydrate-active enzymes are produced by microbial pathogens...... and insects responsible of severe crop losses. Plants have evolved proteinaceous inhibitors to modulate the activity of several of these enzymes. The continuing discovery of new inhibitors indicates that this research area is still unexplored and may lead to new exciting developments. To date, the role...... of the inhibitors is not completely understood. Here we review recent results obtained on the best characterised inhibitors, pointing to their possible biological role in vivo. Results recently obtained with plant transformation technology indicate that this class of inhibitors has potential biotechnological...

  18. A pharmacologically-based array to identify targets of cyclosporine A-induced toxicity in cultured renal proximal tubule cells

    Energy Technology Data Exchange (ETDEWEB)

    Sarró, Eduard, E-mail: [Departament de Bioquímica i Biologia Molecular, Unitat de Bioquímica de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona) (Spain); Renal Physiopathology, CIBBIM-Nanomedicine, Vall d' Hebron Research Institute (VHIR), 08035 Barcelona (Spain); Jacobs-Cachá, Conxita, E-mail: [Renal Physiopathology, CIBBIM-Nanomedicine, Vall d' Hebron Research Institute (VHIR), 08035 Barcelona (Spain); Itarte, Emilio, E-mail: [Departament de Bioquímica i Biologia Molecular, Unitat de Bioquímica de Biociències, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona) (Spain); Meseguer, Anna, E-mail: [Renal Physiopathology, CIBBIM-Nanomedicine, Vall d' Hebron Research Institute (VHIR), 08035 Barcelona (Spain); Departament de Bioquimica i Biologia Molecular, Facultat de Medicina, Universitat Autònoma de Barcelona, 08193 Bellaterra (Barcelona) (Spain)


    Mechanisms of cyclosporine A (CsA)-induced nephrotoxicity were generally thought to be hemodynamic in origin; however, there is now accumulating evidence of a direct tubular effect. Although genomic and proteomic experiments by our group and others provided overall information on genes and proteins up- or down-regulated by CsA in proximal tubule cells (PTC), a comprehensive view of events occurring after CsA exposure remains to be described. For this purpose, we applied a pharmacologic approach based on the use of known activities of a large panel of potentially protective compounds and evaluated their efficacy in preventing CsA toxicity in cultured mouse PTC. Our results show that compounds that blocked protein synthesis and apoptosis, together with the CK2 inhibitor DMAT and the PI3K inhibitor apigenin, were the most efficient in preventing CsA toxicity. We also identified GSK3, MMPs and PKC pathways as potential targets to prevent CsA damage. Additionally, heparinase-I and MAPK inhibitors afforded partial but significant protection. Interestingly, antioxidants and calcium metabolism-related compounds were unable to ameliorate CsA-induced cytotoxicity. Subsequent experiments allowed us to clarify the hierarchical relationship of targeted pathways after CsA treatment, with ER stress identified as an early effector of CsA toxicity, which leads to ROS generation, phenotypical changes and cell death. In summary, this work presents a novel experimental approach to characterizing cellular responses to cytotoxics while pointing to new targets to prevent CsA-induced toxicity in proximal tubule cells. Highlights: ► We used a novel pharmacological approach to elucidate cyclosporine (CsA) toxicity. ► The ability of a broad range of compounds to prevent CsA toxicity was evaluated. ► CsA toxicity was monitored using LDH release assay and PARP cleavage. ► Protein synthesis, PI3K, GSK3, MMP, PKC and caspase inhibitors prevented CsA toxicity. ► We also identified ER

  19. AZT as a telomerase inhibitor

    Directory of Open Access Journals (Sweden)

    Daniel E Gomez


    Full Text Available Telomerase is a highly specialized reverse transcriptase and the maintenance of telomeric length is determined by this specific enzyme. The human holoenzyme telomerase is a ribonucleoprotein composed by a catalytic subunit, hTERT, an RNA component, hTR, and a group of associated proteins. Telomerase is normally expressed in embryonic cells and is repressed during adulthood. The enzyme is reexpressed in around 85% of solid tumors. This observation makes it a potential target for developing drugs that could be developed for therapeutic purposes. The identification of the hTERT as a functional catalytic reverse transcriptase prompted studies of inhibiting telomerase with the HIV reverse transcriptase inhibitor azidothymidine (AZT. Previously, we have demonstrated that AZT binds preferentially to telomeres, inhibits telomerase and enhances tumor cell senescence and apoptosis after AZT treatment in breast mammary adenocarcinoma cells. Since then, several studies have considered AZT for telomerase inhibition and have led to potential clinical strategies for anticancer therapy. This review covers present thinking of the inhibition of telomerase by AZT and future treatment protocols using the drug.

  20. ALK inhibitors, a pharmaceutical perspective

    Directory of Open Access Journals (Sweden)

    Arturo eGalvani


    Full Text Available In 2007, the ALK tyrosine kinase, already known to be translocated and activated in Anaplastic Large Cell Lymphoma, and a few other rare cancers, was described as a potential therapeutic target for a subset of non small-cell lung cancer (NSCLC patients. Clinical proof of concept, culminating in the recent approval by the FDA of the Pfizer drug Xalkori (crizotinib, formerly known as PF-02341066 followed in record time. The drug was approved together with a companion diagnostic, the Vysis ALK Break Apart FISH Probe Kit (Abbott Molecular, Inc. for detection of eligible patients. This remarkable example of the coming of age of personalized medicine in cancer therapy is hopefully only an auspice of things to come in this rapidly developing field. Perhaps unsurprisingly, however, the appearance of clinical acquired resistance to crizotinib has already been observed early on in clinical testing, with the identification of several ALK secondary point mutations which diminish drug efficacy, and which open the way for development of second-generation inhibitors. It is also emerging that acquired resistance to crizotinib may also occur through ALK-independent mechanisms, which still need to be elucidated in detail.

  1. Novel Toxoplasma gondii inhibitor chemotypes. (United States)

    Sanford, A G; Schulze, T T; Potluri, L P; Hemsley, R M; Larson, J J; Judge, A K; Zach, S J; Wang, X; Charman, S A; Vennerstrom, J L; Davis, P H


    We profiled three novel T. gondii inhibitors identified from an antimalarial phenotypic high throughput screen (HTS) campaign: styryl 4-oxo-1,3-benzoxazin-4-one KG3, tetrahydrobenzo[b]pyran KG7, and benzoquinone hydrazone KG8. These compounds inhibit T. gondii in vitro with IC 50 values ranging from 0.3 to 2μM, comparable to that of 0.25 to 1.5μM for the control drug pyrimethamine. KG3 had no measurable cytotoxicity against five mammalian cell lines, whereas KG7 and KG8 inhibited the growth of 2 of 5 cell lines with KG8 being the least selective for T. gondii. None of the compounds were mutagenic in an Ames assay. Experimental gLogD 7.4 and calculated PSA values for the three compounds were well within the ranges predicted to be favorable for good ADME, even though each compound had relatively low aqueous solubility. All three compounds were metabolically unstable, especially KG3 and KG7. Multiple IP doses of 5mg/kg KG7 and KG8 increased survival in a T. gondii mouse model. Despite their liabilities, we suggest that these compounds are useful starting points for chemical prospecting, scaffold-hopping, and optimization. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Vascular calcification: Inducers and inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Donghyun, E-mail: [Department of Biomedical Engineering, Division of Integrative Engineering, Chung-Ang University, 221 Heukseok-Dong, Dongjak-Gu, Seoul 156-756 (Korea, Republic of)


    Highlights: {center_dot} Types of vascular calcification processes. {center_dot} Inducers of vascular calcification. {center_dot} Inhibitors of vascular calcifications. {center_dot} Clinical utility for vascular calcification therapy. {center_dot} Implications for the development of new tissue engineering strategies. - Abstract: Unlike the traditional beliefs, there are mounting evidences suggesting that ectopic mineral depositions, including vascular calcification are mostly active processes, many times resembling that of the bone mineralization. Numbers of agents are involved in the differentiation of certain subpopulation of smooth muscle cells (SMCs) into the osteoblast-like entity, and the activation and initiation of extracellular matrix ossification process. On the other hand, there are factors as well, that prevent such differentiation and ectopic calcium phosphate formation. In normal physiological environments, activities of such procalcific and anticalcific regulatory factors are in harmony, prohibiting abnormal calcification from occurring. However, in certain pathophysiological conditions, such as atherosclerosis, chronic kidney disease (CKD), and diabetes, such balances are altered, resulting in abnormal ectopic mineral deposition. Understanding the factors that regulate the formation and inhibition of ectopic mineral formation would be beneficial in the development of tissue engineering strategies for prevention and/or treatment of such soft-tissue calcification. Current review focuses on the factors that seem to be clinically relevant and/or could be useful in developing future tissue regeneration strategies. Clinical utilities and implications of such factors are also discussed.

  3. Development of green vapour corrosion inhibitor (United States)

    Asmara, Y. P.; Suraj, V.; Siregar, J. P.; Kurniawan, T.; Bachtiar, D.; Mohamed, N. M. Z. N.


    Corrosion control using inhibitor is an effective method to protect carbon steel from corrosion. Due to environmental toxicity of chemical inorganic corrosion inhibitors (synthetic), green inhibitors are potentially to develop. In atmospheric conditions, green vapour corrosion inhibitors are the best solutions to replace the uses of inorganic corrosion inhibitors. This research used chemical acid extraction from the key lime (citrus aurantiifolia) leaves and seeds. They are used as the main ingredients to produce this effective green corrosion inhibitor. The experiments investigated effects of corrosion inhibition on corrosion rate of low carbon steel in 3% NaCl solution using both fog salt chamber and electrochemical cell. Using salt fog chamber to represent atmospheric conditions, and corrosion rates are evaluated visually and calculated using weight loss methods. Corrosion rate on electrochemical cell were calculated using linear polarization resistance (LPR) methods. All of the experiments were set in natural conditions at pH 7. Using weight loss for three days exposure time, the efficiency of the inhibitor reached 82.39%.

  4. Histone Deacetylase Inhibitors as Anticancer Drugs

    Directory of Open Access Journals (Sweden)

    Tomas Eckschlager


    Full Text Available Carcinogenesis cannot be explained only by genetic alterations, but also involves epigenetic processes. Modification of histones by acetylation plays a key role in epigenetic regulation of gene expression and is controlled by the balance between histone deacetylases (HDAC and histone acetyltransferases (HAT. HDAC inhibitors induce cancer cell cycle arrest, differentiation and cell death, reduce angiogenesis and modulate immune response. Mechanisms of anticancer effects of HDAC inhibitors are not uniform; they may be different and depend on the cancer type, HDAC inhibitors, doses, etc. HDAC inhibitors seem to be promising anti-cancer drugs particularly in the combination with other anti-cancer drugs and/or radiotherapy. HDAC inhibitors vorinostat, romidepsin and belinostat have been approved for some T-cell lymphoma and panobinostat for multiple myeloma. Other HDAC inhibitors are in clinical trials for the treatment of hematological and solid malignancies. The results of such studies are promising but further larger studies are needed. Because of the reversibility of epigenetic changes during cancer development, the potency of epigenetic therapies seems to be of great importance. Here, we summarize the data on different classes of HDAC inhibitors, mechanisms of their actions and discuss novel results of preclinical and clinical studies, including the combination with other therapeutic modalities.

  5. Histone Deacetylase Inhibitors as Anticancer Drugs. (United States)

    Eckschlager, Tomas; Plch, Johana; Stiborova, Marie; Hrabeta, Jan


    Carcinogenesis cannot be explained only by genetic alterations, but also involves epigenetic processes. Modification of histones by acetylation plays a key role in epigenetic regulation of gene expression and is controlled by the balance between histone deacetylases (HDAC) and histone acetyltransferases (HAT). HDAC inhibitors induce cancer cell cycle arrest, differentiation and cell death, reduce angiogenesis and modulate immune response. Mechanisms of anticancer effects of HDAC inhibitors are not uniform; they may be different and depend on the cancer type, HDAC inhibitors, doses, etc. HDAC inhibitors seem to be promising anti-cancer drugs particularly in the combination with other anti-cancer drugs and/or radiotherapy. HDAC inhibitors vorinostat, romidepsin and belinostat have been approved for some T-cell lymphoma and panobinostat for multiple myeloma. Other HDAC inhibitors are in clinical trials for the treatment of hematological and solid malignancies. The results of such studies are promising but further larger studies are needed. Because of the reversibility of epigenetic changes during cancer development, the potency of epigenetic therapies seems to be of great importance. Here, we summarize the data on different classes of HDAC inhibitors, mechanisms of their actions and discuss novel results of preclinical and clinical studies, including the combination with other therapeutic modalities.

  6. An Updated Review of Tyrosinase Inhibitors

    Directory of Open Access Journals (Sweden)

    Te-Sheng Chang


    Full Text Available Tyrosinase is a multifunctional, glycosylated, and copper-containing oxidase, which catalyzes the first two steps in mammalian melanogenesis and is responsible for enzymatic browning reactions in damaged fruits during post-harvest handling and processing. Neither hyperpigmentation in human skin nor enzymatic browning in fruits are desirable. These phenomena have encouraged researchers to seek new potent tyrosinase inhibitors for use in foods and cosmetics. This article surveys tyrosinase inhibitors newly discovered from natural and synthetic sources. The inhibitory strength is compared with that of a standard inhibitor, kojic acid, and their inhibitory mechanisms are discussed.

  7. Contemporary protease inhibitors and cardiovascular risk

    DEFF Research Database (Denmark)

    Lundgren, Jens; Mocroft, Amanda; Ryom, Lene


    PURPOSE OF REVIEW: To review the evidence linking use of HIV protease inhibitors with excess risk of cardiovascular disease (CVD) in HIV+ populations. RECENT FINDINGS: For the two contemporary most frequently used protease inhibitors, darunavir and atazanavir [both pharmacologically boosted...... with ritonavir (/r)], darunavir/r has been shown to be associated with increased CVD risk. The effect is cumulative with longer exposure increasing risk and an effect size comparable to what has been observed for previously developed protease inhibitors. Biological mechanisms may be overlapping and include...... on individualization of care based on underlying risk of CVD....

  8. Calcineurin inhibitors in heart transplantation. (United States)

    Keogh, Anne


    The use of calcineurin inhibitors (CNIs; cyclosporine and tacrolimus) has dramatically increased medium-term life expectancy after heart transplantation but has had only limited impact on long-term outcomes for heart transplant recipients. The original oil-based formulation of cyclosporine has been superceded by a microemulsion formulation (Neoral), which has more predictable pharmacokinetics and allows more precise dose-tailoring. Cyclosporine microemulsion and tacrolimus (Prograf) have a similar efficacy in the prevention of acute rejection of heart transplants, but their use is accompanied by nephrotoxicity and by cardiovascular side effects. The efficacy of immunosuppression can be improved by adjunctive therapy, such as azathioprine, mycophenolate mofetil (MMF; Cellcept), corticosteroids, and induction therapy. One of the most important predictors of patient mortality at >5 years after heart transplantation is cardiac allograft vasculopathy (CAV)/late graft failure, which accounts for 31% of deaths. Neither cyclosporine nor tacrolimus have been shown to prevent the development of CAV. In terms of efficacy, MMF provides a modest advantage over azathioprine in preventing CAV, and the combination of cyclosporine plus MMF results in significantly lower mortality than cyclosporine plus azathioprine. Overall, CNIs have multiple cardiovascular side effects, such as hypertension, hyperlipidemia and new-onset diabetes after transplantation, although cyclosporine and tacrolimus have somewhat different cardiovascular side-effect profiles. The challenge in choosing the best immunosuppressive regimen is to balance efficacy and safety to optimize graft and patient survival over the course of many decades. Because cyclosporine and tacrolimus have similar efficacy against acute rejection the choice of CNI for heart transplant recipients should be based on the relative risk of cardiovascular and renal side effects.

  9. Predicting the Performance of Organic Corrosion Inhibitors

    Directory of Open Access Journals (Sweden)

    David A. Winkler


    Full Text Available The withdrawal of effective but toxic corrosion inhibitors has provided an impetus for the discovery of new, benign organic compounds to fill that role. Concurrently, developments in the high-throughput synthesis of organic compounds, the establishment of large libraries of available chemicals, accelerated corrosion inhibition testing technologies, and the increased capability of machine learning methods have made discovery of new corrosion inhibitors much faster and cheaper than it used to be. We summarize these technical developments in the corrosion inhibition field and describe how data-driven machine learning methods can generate models linking molecular properties to corrosion inhibition that can be used to predict the performance of materials not yet synthesized or tested. We briefly summarize the literature on quantitative structure–property relationships models of small organic molecule corrosion inhibitors. The success of these models provides a paradigm for rapid discovery of novel, effective corrosion inhibitors for a range of metals and alloys in diverse environments.

  10. Kinase inhibitors for advanced medullary thyroid carcinoma

    Directory of Open Access Journals (Sweden)

    Martin Schlumberger


    Full Text Available The recent availability of molecular targeted therapies leads to a reconsideration of the treatment strategy for patients with distant metastases from medullary thyroid carcinoma. In patients with progressive disease, treatment with kinase inhibitors should be offered.

  11. Electrochemical Behaviour of Environmentally Friendly Inhibitor of ...

    African Journals Online (AJOL)

    Electrochemical Behaviour of Environmentally Friendly Inhibitor of Aloe Secundiflora Extract in Corrosion Control of Carbon Steel in Soft Water Media. ... corrosion control in neutral and aerated soft water solutions have been investigated using electrochemical impedance spectroscopy and Tafel polarization techniques.

  12. Inhibitors of Acetylcholinesterase and Butyrylcholinesterase Meet Immunity

    Directory of Open Access Journals (Sweden)

    Miroslav Pohanka


    Full Text Available Acetylcholinesterase (AChE inhibitors are widely used for the symptomatic treatment of Alzheimer’s disease and other dementias. More recent use is for myasthenia gravis. Many of these inhibitors interact with the second known cholinesterase, butyrylcholinesterase (BChE. Further, evidence shows that acetylcholine plays a role in suppression of cytokine release through a “cholinergic anti-inflammatory pathway” which raises questions about the role of these inhibitors in the immune system. This review covers research and discussion of the role of the inhibitors in modulating the immune response using as examples the commonly available drugs, donepezil, galantamine, huperzine, neostigmine and pyridostigmine. Major attention is given to the cholinergic anti-inflammatory pathway, a well-described link between the central nervous system and terminal effector cells in the immune system.

  13. Small-Molecule Inhibitors of Urea Transporters (United States)

    Verkman, Alan S.; Esteva-Font, Cristina; Cil, Onur; Anderson, Marc O.; Li, Fei; Li, Min; Lei, Tianluo; Ren, Huiwen; Yang, Baoxue


    Urea transporter (UT) proteins, which include isoforms of UT-A in kidney tubule epithelia and UT-B in vasa recta endothelia and erythrocytes, facilitate urinary concentrating function. Inhibitors of urea transporter function have potential clinical applications as sodium-sparing diuretics, or ‘urearetics,’ in edema from different etiologies, such as congestive heart failure and cirrhosis, as well as in syndrome of inappropriate antidiuretic hormone (SIADH). High-throughput screening of drug-like small molecules has identified UT-A and UT-B inhibitors with nanomolar potency. Inhibitors have been identified with different UT-A versus UT-B selectivity profiles and putative binding sites on UT proteins. Studies in rodent models support the utility of UT inhibitors in reducing urinary concentration, though testing in clinically relevant animal models of edema has not yet been done. PMID:25298345

  14. The effect of chemical anti-inhibitors on fibrinolytic enzymes and inhibitors

    DEFF Research Database (Denmark)

    Sidelmann, Johannes Jakobsen; Jespersen, J; Kluft, C


    proteases. We studied the influence of chemical anti-inhibitors (chloramine T, flufenamate, sodium lauryl sulfate, and methylamine) on fibrinolytic serine proteases and fibrinolytic enzyme inhibitors using the physiological substrate fibrin as plasmin substrate. Low concentrations of chloramine T (0.01 mmol....../l) prevent the inhibition of plasminogen activators. Higher concentrations (1 mmol/l) reduce the inhibition of plasmin, but simultaneously quench the plasminogen activator activity. Flufenamate eliminates most fibrinolytic enzyme inhibitors, but increases the activity of plasmin (apparent recovery 140......Fibrinolytic enzyme inhibitors hamper the determination of the specific fibrinolytic serine protease activity. Reportedly, chemical anti-inhibitors eliminate the influence of fibrinolytic inhibitors, but it remains unclear to what extent they change the specific activity of fibrinolytic serine...

  15. Monoamine Oxidase B Inhibitors in Parkinson's Disease. (United States)

    Dezsi, Livia; Vecsei, Laszlo


    Parkinson's disease (PD) is a neurodegenerative disorder with a prevalence increasing with age. Oxidative stress and glutamate toxicity are involved in its pathomechanism. There are still many unmet needs of PD patients, including the alleviation of motor fluctuations and dyskinesias, and the development of therapies with neuroprotective potential. To give an overview of the pharmacological properties, the efficacy and safety of the monoamine oxidase B (MAO-B) inhibitors in the treatment of PD, with special focus on the results of randomized clinical trials. A literature search was conducted in PubMed for 'PD treatment', 'MAO-B inhibitors', 'selegiline', 'rasagiline', 'safinamide' and 'clinical trials' with 'MAO-B inhibitors' in 'Parkinson' disease'. MAO-B inhibitors have a favorable pharmacokinetic profile, improve the dopamine deficient state and may have neuroprotective properties. Safinamide exhibits an anti-glutamatergic effect as well. When applied as monotherapy, MAO-B inhibitors provide a modest, but significant improvement of motor function and delay the need for levodopa. Rasagiline and safinamide were proven safe and effective when added to a dopamine agonist in early PD. As add-on to levodopa, MAO-B inhibitors significantly reduced off-time and were comparable in efficacy to COMT inhibitors. Improvements were achieved as regards certain non-motor symptoms as well. Due to the efficacy shown in clinical trials and their favorable side-effect profile, MAO-B inhibitors are valuable drugs in the treatment of PD. They are recommended as monotherapy in the early stages of the disease and as add-on therapy to levodopa in advanced PD. Copyright© Bentham Science Publishers; For any queries, please email at

  16. Update on TNF Inhibitors in Dermatology. (United States)

    Sobell, Jeffrey M


    Emerging data describe new potential indications for tumor necrosis factor (TNF) inhibitors in dermatology, including pediatric psoriasis and hidradenitis suppurativa. New biosimilar TNF agents are in late stages of development and may be available in the United States in the near future. Biosimilar agents are similar but not identical to available TNF inhibitors, and approval requires extensive analytic, toxicity, pharmacokinetic, pharmacodynamic, and clinical testing. Semin Cutan Med Surg 35(supp6):S104-S106. 2016 published by Frontline Medical Communications.

  17. Emerging Corrosion Inhibitors for Interfacial Coating

    Directory of Open Access Journals (Sweden)

    Mona Taghavikish


    Full Text Available Corrosion is a deterioration of a metal due to reaction with environment. The use of corrosion inhibitors is one of the most effective ways of protecting metal surfaces against corrosion. Their effectiveness is related to the chemical composition, their molecular structures and affinities for adsorption on the metal surface. This review focuses on the potential of ionic liquid, polyionic liquid (PIL and graphene as promising corrosion inhibitors in emerging coatings due to their remarkable properties and various embedment or fabrication strategies. The review begins with a precise description of the synthesis, characterization and structure-property-performance relationship of such inhibitors for anti-corrosion coatings. It establishes a platform for the formation of new generation of PIL based coatings and shows that PIL corrosion inhibitors with various heteroatoms in different form can be employed for corrosion protection with higher barrier properties and protection of metal surface. However, such study is still in its infancy and there is significant scope to further develop new structures of PIL based corrosion inhibitors and coatings and study their behaviour in protection of metals. Besides, it is identified that the combination of ionic liquid, PIL and graphene could possibly contribute to the development of the ultimate corrosion inhibitor based coating.

  18. Aromatase inhibitors in the treatment of endometriosis

    Directory of Open Access Journals (Sweden)

    Radosław Słopień


    Full Text Available Endometriosis is a chronic inflammatory condition in which foci of endometrial tissue grow outside of the uterine cavity. Endometriosis was estimated to affect 176 million women of childbearing potential all over the world in 2010. The presence of extrauterine endometrial tissue is associated with pain and infertility. Typical symptoms of endometriosis include dysmenorrhoea, dyspareunia, heavy menstrual periods (menorrhagia, pelvic pain that is not related to menstrual cycles, dysuria, and chronic fatigue. Medical treatments for endometriosis include combined oral contraceptive pills, danazol, gestrinone, medroxyprogesterone acetate, and gonadotropin-releasing hormone agonists (aGnRHs. A new class of medications called aromatase inhibitors has been identified in recent years as potential therapeutic agents for endometriosis. This article provides general information about aromatase inhibitors, their use in gynaecology, and their adverse effects. In particular, the paper discusses the use of aromatase inhibitors in the treatment of endometriosis in postmenopausal women. Unlike oral contraceptives, gestagens, aGnRHs, and danazol, which suppress ovarian oestrogen synthesis, aromatase inhibitors inhibit mainly extra-ovarian synthesis of oestrogens. Therefore, the use of aromatase inhibitors seems to be particularly relevant in older patients, as most of the body’s oestrogen is produced outside the ovaries after menopause. The paper discusses also the use of aromatase inhibitors in the treatment of pain associated with endometriosis and infertility caused by endometriosis.

  19. Casein Kinase 2 Is a Novel Regulator of the Human Organic Anion Transporting Polypeptide 1A2 (OATP1A2) Trafficking. (United States)

    Chan, Ting; Cheung, Florence Shin Gee; Zheng, Jian; Lu, Xiaoxi; Zhu, Ling; Grewal, Thomas; Murray, Michael; Zhou, Fanfan


    Human organic anion transporting polypeptides (OATPs) mediate the influx of many important drugs into cells. Casein kinase 2 (CK2) is a critical protein kinase that phosphorylates >300 protein substrates and is dysregulated in a number of disease states. Among the CK2 substrates are several transporters, although whether this includes human OATPs has not been evaluated. The current study was undertaken to evaluate the regulation of human OATP1A2 by CK2. HEK-239T cells in which OATP1A2 was overexpressed were treated with CK2 specific inhibitors or transfected with CK2 specific siRNA, and the activity, expression, and subcellular trafficking of OATP1A2 was evaluated. CK2 inhibition decreased the uptake of the prototypic OATP1A2 substrate estrone-3-sulfate (E3S). Kinetic studies revealed that this was due to a decrease in the maximum velocity (Vmax) of E3S uptake, while the Michaelis constant was unchanged. The cell surface expression, but not the total cellular expression of OATP1A2, was impaired by CK2 inhibition and knockdown of the catalytic α-subunits of CK2. CK2 inhibition decreased the internalization of OATP1A2 via a clathrin-dependent pathway, decreased OATP1A2 recycling, and likely impaired OATP1A2 targeting to the cell surface. Consistent with these findings, CK2 inhibition also disrupted the colocalization of OATP1A2 and Rab GTPase (Rab)4-, Rab8-, and Rab9-positive endosomal and secretory vesicles. Taken together, CK2 has emerged as a novel regulator of the subcellular trafficking and stability of OATP1A2. Because OATP1A2 transports many molecules of physiological and pharmacological importance, the present data may inform drug selection in patients with diseases in which CK2 and OATP1A2 are dysregulated.

  20. Combined effects of EGFR tyrosine kinase inhibitors and vATPase inhibitors in NSCLC cells

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Hyeon-Ok [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Hong, Sung-Eun [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Kim, Chang Soon [Department of Microbiological Engineering, Kon-Kuk University, 120 Neungdong-ro, Gwangjin-gu, Seoul, 143–701 (Korea, Republic of); Park, Jin-Ah; Kim, Jin-Hee; Kim, Ji-Young; Kim, Bora [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Chang, Yoon Hwan; Hong, Seok-Il; Hong, Young Jun [Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Park, In-Chul, E-mail: [Division of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Lee, Jin Kyung, E-mail: [KIRAMS Radiation Biobank, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of); Department of Laboratory Medicine, Korea Cancer Center Hospital, Korea Institute of Radiological and Medical Sciences, 75 Nowon-ro, Nowon-gu, Seoul, 139–706 (Korea, Republic of)


    Despite excellent initial clinical responses of non-small cell lung cancer (NSCLC) patients to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), many patients eventually develop resistance. According to a recent report, vacuolar H + ATPase (vATPase) is overexpressed and is associated with chemotherapy drug resistance in NSCLC. We investigated the combined effects of EGFR TKIs and vATPase inhibitors and their underlying mechanisms in the regulation of NSCLC cell death. We found that combined treatment with EGFR TKIs (erlotinib, gefitinib, or lapatinib) and vATPase inhibitors (bafilomycin A1 or concanamycin A) enhanced synergistic cell death compared to treatments with each drug alone. Treatment with bafilomycin A1 or concanamycin A led to the induction of Bnip3 expression in an Hif-1α dependent manner. Knock-down of Hif-1α or Bnip3 by siRNA further enhanced cell death induced by bafilomycin A1, suggesting that Hif-1α/Bnip3 induction promoted resistance to cell death induced by the vATPase inhibitors. EGFR TKIs suppressed Hif-1α and Bnip3 expression induced by the vATPase inhibitors, suggesting that they enhanced the sensitivity of the cells to these inhibitors by decreasing Hif-1α/Bnip3 expression. Taken together, we conclude that EGFR TKIs enhance the sensitivity of NSCLC cells to vATPase inhibitors by decreasing Hif-1α/Bnip3 expression. We suggest that combined treatment with EGFR TKIs and vATPase inhibitors is potentially effective for the treatment of NSCLC. - Highlights: • Co-treatment with EGFR TKIs and vATPase inhibitors induces synergistic cell death • EGFR TKIs enhance cell sensitivity to vATPase inhibitors via Hif-1α downregulation • Co-treatment of these inhibitors is potentially effective for the treatment of NSCLC.

  1. Small molecule HIV entry inhibitors: Part II. Attachment and fusion inhibitors: 2004-2010. (United States)

    Singh, Inder Pal; Chauthe, Siddheshwar Kisan


    The first US FDA approved HIV entry inhibitor drug Enfuvirdine belongs to the fusion inhibitor category. Earlier efforts in this area were focused on peptides and monoclonal antibodies; recently, the focus has shifted towards the development of small molecule HIV attachment and fusion inhibitors. They can be used for prophylactic purposes and also hold potential for the development of HIV microbicides. In a previous paper ('Small molecule HIV entry inhibitors: Part I'), we reviewed patents and patent applications for small molecule chemokine receptor antagonists from major pharmaceutical companies. In this paper, the development of small molecule HIV attachment and fusion inhibitors is discussed in detail. It covers patents and patent applications for small molecule HIV attachment and fusion inhibitors published between 2004 and 2010 and related literature with a focus on recent developments based on lead generation and lead modification. To augment the potency of currently available antiretroviral drug combinations and to fight drug-resistant virus variants, more effective drugs which target additional steps in the viral replication cycle are urgently needed. HIV attachment and fusion processes are such targets. Inhibitors of these targets will provide additional options for the treatment of HIV drug-resistant strains. Small molecule HIV attachment inhibitors such as BMS-378806 and analogs from Bristol Myers Squibb, N-aryl piperidine derivatives from Propharmacon, and NBD-556 and NBD-557 from New York Blood Center may have potential as vaginal microbicidal agents and can be an economical alternative to monoclonal antibodies.

  2. Polyphenol oxidase inhibitor(s) from German cockroach (Blattella germanica) extract (United States)

    An extract from German cockroach appears effective in inhibiting browning on apples and potatoes. Successful identification of inhibitor(s) of PPO from German cockroach would be useful to the fruit and vegetable segments of the food industry, due to the losses they incur from enzymatic browning. Ide...

  3. Monoamine Reuptake Inhibitors in Parkinson's Disease (United States)

    Huot, Philippe; Fox, Susan H.; Brotchie, Jonathan M.


    The motor manifestations of Parkinson's disease (PD) are secondary to a dopamine deficiency in the striatum. However, the degenerative process in PD is not limited to the dopaminergic system and also affects serotonergic and noradrenergic neurons. Because they can increase monoamine levels throughout the brain, monoamine reuptake inhibitors (MAUIs) represent potential therapeutic agents in PD. However, they are seldom used in clinical practice other than as antidepressants and wake-promoting agents. This review article summarises all of the available literature on use of 50 MAUIs in PD. The compounds are divided according to their relative potency for each of the monoamine transporters. Despite wide discrepancy in the methodology of the studies reviewed, the following conclusions can be drawn: (1) selective serotonin transporter (SERT), selective noradrenaline transporter (NET), and dual SERT/NET inhibitors are effective against PD depression; (2) selective dopamine transporter (DAT) and dual DAT/NET inhibitors exert an anti-Parkinsonian effect when administered as monotherapy but do not enhance the anti-Parkinsonian actions of L-3,4-dihydroxyphenylalanine (L-DOPA); (3) dual DAT/SERT inhibitors might enhance the anti-Parkinsonian actions of L-DOPA without worsening dyskinesia; (4) triple DAT/NET/SERT inhibitors might exert an anti-Parkinsonian action as monotherapy and might enhance the anti-Parkinsonian effects of L-DOPA, though at the expense of worsening dyskinesia. PMID:25810948

  4. Janus kinase inhibitors: jackpot or potluck?

    Directory of Open Access Journals (Sweden)

    Pavithran Keechilat


    Full Text Available The reports of a unique mutation in the Janus kinase-2 gene (JAK2 in polycythemia vera by several independent groups in 2005 quickly spurred the development of the Janus kinase inhibitors. In one of the great victories of translational research in recent times, the first smallmolecule Janus kinase inhibitor ruxolitinib entered a phase I trial in 2007. With the approval of ruxolitinib by the US Federal Drug Administration in November 2011 for high-risk and intermediate-2 risk myelofibrosis, a change in paradigm has occurred in the management of a subset of myeloproliferative neoplasms (MPN: primary myelofibrosis, post-polycythemia vera myelofibrosis, and post-essential thrombocythemia myelofibrosis. Whereas the current evidence for ruxolitinib only covers high-risk and intermediate-2 risk myelofibrosis, inhibitors with greater potency are likely to offer better disease control and survival advantage in patients belonging to these categories, and possibly to the low-risk and intermediate-1 risk categories of MPN as well. But use of the Janus kinase inhibitors also probably has certain disadvantages, such as toxicity, resistance, withdrawal phenomenon, non-reversal of histology, and an implausible goal of disease clone eradication, some of which could offset the gains. In spite of this, Janus kinase inhibitors are here to stay, and for use in more than just myeloproliferative neoplasms.

  5. Protease Inhibitors from Plants with Antimicrobial Activity

    Directory of Open Access Journals (Sweden)

    Yoonkyung Park


    Full Text Available Antimicrobial proteins (peptides are known to play important roles in the innate host defense mechanisms of most living organisms, including plants, insects, amphibians and mammals. They are also known to possess potent antibiotic activity against bacteria, fungi, and even certain viruses. Recently, the rapid emergence of microbial pathogens that are resistant to currently available antibiotics has triggered considerable interest in the isolation and investigation of the mode of action of antimicrobial proteins (peptides. Plants produce a variety of proteins (peptides that are involved in the defense against pathogens and invading organisms, including ribosome-inactivating proteins, lectins, protease inhibitors and antifungal peptides (proteins. Specially, the protease inhibitors can inhibit aspartic, serine and cysteine proteinases. Increased levels of trypsin and chymotrypsin inhibitors correlated with the plants resistance to the pathogen. Usually, the purification of antimicrobial proteins (peptides with protease inhibitor activity was accomplished by salt-extraction, ultrafiltration and C18 reverse phase chromatography, successfully. We discuss the relation between antimicrobial and anti-protease activity in this review. Protease inhibitors from plants potently inhibited the growth of a variety of pathogenic bacterial and fungal strains and are therefore excellent candidates for use as the lead compounds for the development of novel antimicrobial agents.

  6. [Interaction between clopidogrel and proton pump inhibitors]. (United States)

    Harmsze, Ankie M; de Boer, Anthonius; Boot, Henk; Deneer, Vera H M; Heringa, Mette; Mol, Peter G M; Schalekamp, Tom; Verduijn, Monique M; Verheugt, Freek W A; le Comte, Marianne


    The drug interaction between proton pump inhibitors and clopidogrel has been the subject of much study in recent years. Contradictory results regarding the effect of proton pump inhibitors on platelet reactivity and on clinical outcome in clopidogrel-treated patients have been reported in literature. Concomitant use of omeprazole and clopidogrel was found to decrease the exposure (AUC) to clopidogrel's active metabolite by 50% and to sharply increase platelet reactivity, as a result of inhibition by omeprazole of CYP2C19, a cytochrome P450 (CYP) enzyme. Pantoprazole has a much weaker effect on clopidogrel's pharmacokinetics and on platelet reactivity during concomitant use. The influence of the other proton pump inhibitors when used simultaneously with clopidogrel has not yet been investigated in adequately randomized studies. Regulatory agencies state that the combination of clopidogrel and the CYP2C19 inhibitors omeprazole and esomeprazole should be avoided. To date, there is no conclusive evidence of a clinically-relevant interaction between any of the proton pump inhibitors and clopidogrel.

  7. Novel peptide-based protease inhibitors

    DEFF Research Database (Denmark)

    Roodbeen, Renée

    This thesis describes the design and synthesis of peptide-based serine protease inhibitors. The targeted protease, urokinase-type plasminogen activator (uPA) activates plasminogen, which plays a major role in cancer metastasis. The peptide upain-2 (S 1 ,S 12-cyclo-AcCSWRGLENHAAC-NH2) is a highly......, the disulfide bridge was replaced with amide bonds of various lengths. The novel peptides did not retain their inhibitory activity, but formed the basis for another strategy. Second, bicyclic peptides were obtained by creating head-to-tail cyclized peptides that were made bicyclic by the addition of a covalent...... bond across the ring. The second bridge was made by a disulfide bridge, amide bond formation or via ring-closing metathesis. A, with upain-2 equipotent, bicyclic inhibitor was obtained and its binding to uPA was studied by ITC, NMR and X-ray. The knowledge of how selective inhibitors bind uPA has been...

  8. Human tyrosinase inhibitor in rum distillate wastewater. (United States)

    Takara, Kensaku; Iwasaki, Hironori; Ujihara, Kunihiro; Wada, Koji


    An inhibitor of human tyrosinase activity in rum distillate wastewater was isolated and identified as (S)-(+)-imperanene (1). (S)-(+)-Imperanene significantly inhibited tyrosinase isolated from HMV-II cells (IC(50) 1.85 mM). Inhibition kinetics studies revealed that imperanene is a competitive inhibitor of tyrosinase when L-3,4-dihydroxyphenylalanine is used as the substrate. The inhibitory activities of 1, O-beta-D-glucopyranosyl imperanene (2) and O-beta-D-glucopyranosyl-3-methoxyl imperanene (3) were 1>2>3.

  9. Does plasminogen activator inhibitor-1 drive lymphangiogenesis?

    DEFF Research Database (Denmark)

    Bruyère, Françoise; Melen-Lamalle, Laurence; Blacher, Silvia


    The purpose of this study is to explore the function of plasminogen activator inhibitor-1 (PAI-1) during pathological lymphangiogenesis. PAI-1, the main physiological inhibitor of plasminogen activators is involved in pathological angiogenesis at least by controlling extracellular proteolysis...... by mammary carcinoma cell injection or spontaneously appearing in transgenic mice expressing the polyomavirus middle T antigen (PymT) under the control of a mouse mammary tumor virus long-terminal repeat promoter (MMTV-LTR). We also investigated inflammation-related lymphatic vessel recruitment by using two...... as a potential therapeutic target to counteract pathological lymphangiogenesis....

  10. A cyclic peptidic serine protease inhibitor

    DEFF Research Database (Denmark)

    Zhao, Baoyu; Xu, Peng; Jiang, Longguang


    plasminogen activator (uPA). We used X-ray crystal structure analysis, site-directed mutagenesis, liquid state NMR, surface plasmon resonance analysis, and isothermal titration calorimetry and wild type and engineered variants of murine and human uPA. We demonstrate that Arg6 inserts into the S1 specificity......Peptides are attracting increasing interest as protease inhibitors. Here, we demonstrate a new inhibitory mechanism and a new type of exosite interactions for a phage-displayed peptide library-derived competitive inhibitor, mupain-1 (CPAYSRYLDC), of the serine protease murine urokinase-type...

  11. 2-Aminobenzimidazoles as potent Aurora kinase inhibitors. (United States)

    Zhong, Min; Bui, Minna; Shen, Wang; Baskaran, Subramanian; Allen, Darin A; Elling, Robert A; Flanagan, W Michael; Fung, Amy D; Hanan, Emily J; Harris, Shannon O; Heumann, Stacey A; Hoch, Ute; Ivy, Sheryl N; Jacobs, Jeffrey W; Lam, Stuart; Lee, Heman; McDowell, Robert S; Oslob, Johan D; Purkey, Hans E; Romanowski, Michael J; Silverman, Jeffrey A; Tangonan, Bradley T; Taverna, Pietro; Yang, Wenjin; Yoburn, Josh C; Yu, Chul H; Zimmerman, Kristin M; O'Brien, Tom; Lew, Willard


    This Letter describes the discovery and key structure-activity relationship (SAR) of a series of 2-aminobenzimidazoles as potent Aurora kinase inhibitors. 2-Aminobenzimidazole serves as a bioisostere of the biaryl urea residue of SNS-314 (1c), which is a potent Aurora kinase inhibitor and entered clinical testing in patients with solid tumors. Compared to SNS-314, this series of compounds offers better aqueous solubility while retaining comparable in vitro potency in biochemical and cell-based assays; in particular, 6m has also demonstrated a comparable mouse iv PK profile to SNS-314.

  12. Synergistic apoptosis induction in leukemic cells by the phosphatase inhibitor salubrinal and proteasome inhibitors.

    Directory of Open Access Journals (Sweden)

    Hannes C A Drexler

    Full Text Available Cells adapt to endoplasmic reticulum (ER-stress by arresting global protein synthesis while simultaneously activating specific transcription factors and their downstream targets. These processes are mediated in part by the phosphorylation-dependent inactivation of the translation initiation factor eIF2alpha. Following restoration of homeostasis protein synthesis is resumed when the serine/threonine-protein phosphatase PP1 dephosphorylates and reactivates eIF2alpha. Proteasome inhibitors, used to treat multiple myeloma patients evoke ER-stress and apoptosis by blocking the ER-associated degradation of misfolded proteins (ERAD, however, the role of eIF2alpha phosphorylation in leukemic cells under conditions of proteasome inhibitor-mediated ER stress is currently unclear.Bcr-Abl-positive and negative leukemic cell lines were used to investigate the functional implications of PP1-related phosphatase activities on eIF2alpha phosphorylation in proteasome inhibitor-mediated ER stress and apoptosis. Rather unexpectedly, salubrinal, a recently identified PP1 inhibitor capable to protect against ER stress in various model systems, strongly synergized with proteasome inhibitors to augment apoptotic death of different leukemic cell lines. Salubrinal treatment did not affect the phosphorlyation status of eIF2alpha. Furthermore, the proapoptotic effect of salubrinal occurred independently from the chemical nature of the proteasome inhibitor, was recapitulated by a second unrelated phosphatase inhibitor and was unaffected by overexpression of a dominant negative eIF2alpha S51A variant that can not be phosphorylated. Salubrinal further aggravated ER-stress and proteotoxicity inflicted by the proteasome inhibitors on the leukemic cells since characteristic ER stress responses, such as ATF4 and CHOP synthesis, XBP1 splicing, activation of MAP kinases and eventually apoptosis were efficiently abrogated by the translational inhibitor cycloheximide.Although PP1

  13. Proton pump inhibitors affect the gut microbiome

    NARCIS (Netherlands)

    Imhann, Floris; Bonder, Marc Jan; Vich Vila, Arnau; Fu, Jingyuan; Mujagic, Zlatan; Vork, Lisa; Feenstra, Ettje T.; Jankipersadsing, Soesma A; Cenit, Maria Carmen; Harmsen, Hermie J M; Dijkstra, Gerard; Franke, Lude; Xavier, Ramnik J; Jonkers, Daisy; Wijmenga, Cisca; Weersma, Rinse K; Zhernakova, Alexandra

    BACKGROUND AND AIMS: Proton pump inhibitors (PPIs) are among the top 10 most widely used drugs in the world. PPI use has been associated with an increased risk of enteric infections, most notably Clostridium difficile. The gut microbiome plays an important role in enteric infections, by resisting or

  14. Thiosemicarbazones as inhibitors of tyrosinase enzyme. (United States)

    Soares, Mariana A; Almeida, Mariana A; Marins-Goulart, Carla; Chaves, Otávio A; Echevarria, Aurea; de Oliveira, Márcia C C


    In the search for compounds which may inhibit the development of melanomas, a series of thiosemicarbazones has been investigated as possible inhibitors of the tyrosinase enzyme. The results showed that all the thiosemicarbazones tested exhibited significant inhibitory effects on the enzyme. Thiosemicarbazones Thio-1, Thio-2, Thio-3 and Thio-4 substituted with oxygenate moieties, were better inhibitors (IC50 0.42, 0.35, 0.36 and 0.44mM, respectively) than Thio-5, Thio-6, Thio-7 and Thio-8. For the better inhibitors, molecular docking results suggested that the oxygen present in the para position of the aromatic ring is essential for the tyrosinase inhibition, due its high ability for complexation with Cu2+ ions. Inside the active protein pocket, Thio-2 - the best studied inhibitor - is able to interact with the amino acid residues His-155, Gly-170 and Val-172 via hydrogen bonding and hydrophobic force. Thio-2, containing a substituent on the aromatic ring similar to the substrate l-DOPA, showed a competitive inhibition mechanism as viewed in a Lineweaver-Burk plot. The same results were observed in the UV-Vis curves. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Vildagliptin: the first innovative DDP-4 inhibitor


    Edvin Villkhauer


    A review of the main stages of investigation undertaken by Novartis Pharmaceuticals in search of a new molecule for the treatment of type 2 diabetes mellitus, dipeptidyl peptidase-4 (DPP-4) inhibitor (Vildaglyptin). The data on specificity and selectivity of the action of this molecule are presented along with the results of its comparison with another agent of this group (sitagliptin).

  16. TLC bioautographic method for detecting lipase inhibitors. (United States)

    Hassan, Abdel Moniem Sadek


    Bioautographic assays using TLC play an important role in the search for active compounds from plants. A TLC bioautographic assay has previously been established for the detection of acetylcholinesterase inhibitors but not for lipases. Development of a TLC bioautographic method for detecting lipase inhibitors in plant extracts. After migration of the plant extracts, the TLC plate was sprayed with α-naphtyl acetate and enzyme solutions before incubation at 37°C for 20 min. Finally, the solution of Fast Blue B salt was sprayed onto the TLC plate giving a purple background colouration. Lipase inhibitors were visualised as white spots on the TLC plates. Orlistat (a known lipase inhibitor) inhibited lipase down to 0.01 µg. Methanolic extracts of Camellia sinensis (L.) kuntz and Rosmarinus officinalis L after migration on TLC gave enzymatic inhibition when applied in amounts of 82 and 56 µg, respectively. On the other hand the methanolic extract of Morus alba leaves did not exhibit any lipase inhibitory activity. The screening test was able to detect lipase inhibition by pure reference substances and by compounds present in complex matrices, such as plant extracts. Copyright © 2011 John Wiley & Sons, Ltd.

  17. Discovery of inhibitors of bacterial histidine kinases

    NARCIS (Netherlands)

    Velikova, N.R.


    Discovery of Inhibitors of Bacterial Histidine Kinases


    The thesis is on novel antibacterial drug discovery ( Using structure-based and fragment-based

  18. Are phosphodiesterase 4 inhibitors just more theophylline? (United States)

    Boswell-Smith, Victoria; Cazzola, Mario; Page, Clive P


    Theophylline has been relegated to a second- or even third-line therapy in the treatment of asthma and chronic obstructive pulmonary disease (COPD), behind glucocorticosteroids and beta2-agonists, although recent findings have suggested that theophylline possesses anti-inflammatory and immunomodulatory effects in addition to its well-recognized effects as a bronchodilator. In part, theophylline has fallen out of favor because of its adverse side-effect profile, and this has led to the search for more effective and safer drugs based on the knowledge that theophylline is orally active and that it is a nonselective phosphodiesterase (PDE) inhibitor. This has led to the development of selective PDE4 inhibitors, originally designed for depression, for the treatment of both COPD and asthma. Such drugs have shown clinical efficacy in the treatment of respiratory disease while having a considerably safer side-effect profile in comparison with theophylline, particularly because there are no reported drug interactions with PDE4 inhibitors, a feature that complicates the use of theophylline. In addition, it is also becoming increasingly apparent that theophylline is not working solely through PDE inhibition, as formerly assumed, and that this drug has other relevant pharmacologic activities that are likely to contribute to its efficacy, such as adenosine receptor antagonism and induction of histone deacetylase. Thus, the introduction of PDE4 inhibitors represents an entirely new class of drugs for the treatment of respiratory disease.

  19. Viral safety of C1-inhibitor NF

    NARCIS (Netherlands)

    Terpstra, F. G.; Kleijn, M.; Koenderman, A. H. L.; Over, J.; van Engelenburg, F. A. C.; Schuitemaker, H.; van 't Wout, A. B.


    We studied the efficacy of virus reduction by three process steps (polyethylene glycol 4000 (PEG) precipitation, pasteurization, and 15nm virus filtration) in the manufacturing of C1-inhibitor NF. The potential prion removing capacity in this process was estimated based on data from the literature.

  20. Developing ER Stress Inhibitors for Treating ALS (United States)


    in response to thapsigargin, an inhibitor of the sarco/endoplasmic reticulum Ca2+ ATPase ( SERCA ) channels which initiates ER stress by preventing...O’Regan, J. P., Deng, H. X., and et al. (1993) Mutations in Cu/Zn superoxide dismutase gene are associated with familial amyotrophic lateral

  1. Deconstructing Lipid Kinase Inhibitors by Chemical Proteomics. (United States)

    McCloud, Rebecca L; Franks, Caroline E; Campbell, Sean T; Purow, Benjamin W; Harris, Thurl E; Hsu, Ku-Lung


    Diacylglycerol kinases (DGKs) regulate lipid metabolism and cell signaling through ATP-dependent phosphorylation of diacylglycerol to biosynthesize phosphatidic acid. Selective chemical probes for studying DGKs are currently lacking and are needed to annotate isoform-specific functions of these elusive lipid kinases. Previously, we explored fragment-based approaches to discover a core fragment of DGK-α (DGKα) inhibitors responsible for selective binding to the DGKα active site. Here, we utilize quantitative chemical proteomics to deconstruct widely used DGKα inhibitors to identify structural regions mediating off-target activity. We tested the activity of a fragment (RLM001) derived from a nucleotide-like region found in the DGKα inhibitors R59022 and ritanserin and discovered that RLM001 mimics ATP in its ability to broadly compete at ATP-binding sites of DGKα as well as >60 native ATP-binding proteins (kinases and ATPases) detected in cell proteomes. Equipotent inhibition of activity-based probe labeling by RLM001 supports a contiguous ligand-binding site composed of C1, DAGKc, and DAGKa domains in the DGKα active site. Given the lack of available crystal structures of DGKs, our studies highlight the utility of chemical proteomics in revealing active-site features of lipid kinases to enable development of inhibitors with enhanced selectivity against the human proteome.

  2. Curcumin derivatives as HIV-1 protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sui, Z.; Li, J.; Craik, C.S.; Ortiz de Montellano, P.R. [Univ. of California, San Francisco, CA (United States)


    Curcumin, a non-toxic natural compound from Curcuma longa, has been found to be an HIV-1 protease inhibitor. Some of its derivatives were synthesized and their inhibitory activity against the HIV-1 protease was tested. Curcumin analogues containing boron enhanced the inhibitory activity. At least of the the synthesized compounds irreversibly inhibits the HIV-1 protease.

  3. Safety aspects of HIV-protease inhibitors

    NARCIS (Netherlands)

    J.P. Dieleman (Jeanne)


    textabstractThe objectives of this thesis were to provide more insight into the risk and risk factors of adverse drug reactions associated with HIV-protease inhibitor treatment under non-experimental everyday circumstances. By recognition of risk factors, patients at risk can be identified

  4. Curbing indoor mold growth with mold inhibitors (United States)

    Carol A. Clausen; Vina W. Yang


    Environmentally acceptable mold inhibitors are needed to curb the growth of mold fungi in woodframe housing when moisture management measures fail. Excess indoor moisture can lead to rapid mold establishment which, in turn, can have deleterious affects on indoor air quality. Compounds with known mold inhibitory properties and low mammalian toxicity, such as food...

  5. Natural peptides and proteins: potent tyrosinase inhibitors

    Directory of Open Access Journals (Sweden)

    R. Hariri*


    Full Text Available Background and objectives: Tyrosinase is a copper containing oxidase which is crucial for controlling the production of melanin in creatures such as bacteria, fungi, plants and mammals. It is involved in the first two steps of melanin biosynthesis and leads to pigmentation and different types of cancer such as melanoma. Also, it is responsible for browning of fruits and vegetables. Therefore, safe and efficient tyrosinase inhibitors are useful in the field of clinical medicine, cosmetics, agricultural and food industries. Conventional tyrosinase inhibitors such as hydroquinone, kojic acid, and arbutin have suffered from several problems such as melanocytes cytotoxicity, irritation, low permeability through the skin, contact allergy and low stability. Considering these difficulties, researchers have developed various naturally occurring anti-tyrosinase agents and in this regard, peptides and proteins have attracted lots of attention. Methods: In this work, anti-tyrosinase peptides and proteins obtained from natural resources were reviewed using credible databases. Results: Literature survey revealed that development of anti-tyrosinase activity of naturally occurring peptides and proteins started from 1974. Mushrooms (e.g. Agaricushortensis, bacteria (e.g. Lactobacillus helveticus and Oscillatoria agardhii, plants (e.g. Pseudostellaria heterophylla, rice bran,silk and egg yolk have been found as the most potent inhibitors. Conclusion: Literature review depicted that natural peptides and proteins can be consumed efficiently as tyrosinase inhibitors with much lower side effects. In this respect, new horizon will be opened to safe anti-tyrosinase agents.

  6. Structure-Based Design of Ricin Inhibitors

    Directory of Open Access Journals (Sweden)

    Jon D. Robertus


    Full Text Available Ricin is a potent cytotoxin easily purified in large quantities. It presents a significant public health concern due to its potential use as a bioterrorism agent. For this reason, extensive efforts have been underway to develop antidotes against this deadly poison. The catalytic A subunit of the heterodimeric toxin has been biochemically and structurally well characterized, and is an attractive target for structure-based drug design. Aided by computer docking simulations, several ricin toxin A chain (RTA inhibitors have been identified; the most promising leads belonging to the pterin family. Development of these lead compounds into potent drug candidates is a challenging prospect for numerous reasons, including poor solubility of pterins, the large and highly polar secondary binding pocket of RTA, as well as the enzyme’s near perfect catalytic efficiency and tight binding affinity for its natural substrate, the eukaryotic ribosome. To date, the most potent RTA inhibitors developed using this approach are only modest inhibitors with apparent IC50 values in the 10−4 M range, leaving significant room for improvement. This review highlights the variety of techniques routinely employed in structure-based drug design projects, as well as the challenges faced in the design of RTA inhibitors.

  7. Protease inhibitor mediated resistance to insects

    NARCIS (Netherlands)

    Outchkourov, N.S.


    Protease inhibitors (PIs) are among the defensive molecules that plants produce in order to defend themselves against herbivores. A major aim of this thesis is to develop novel insect resistance traits usingheterologous, non-plant PIs. Prerequisite for the success of the

  8. TNF-Alpha Inhibitors for Chronic Urticaria

    DEFF Research Database (Denmark)

    Sand, Freja Lærke; Thomsen, Simon Francis


    had a durable response with a mean of 11 months. Six patients (30%) experienced side effects and five patients had mild recurrent upper respiratory infections, whereas one patient experienced severe CNS toxicity that could be related to treatment with TNF-alpha inhibitor. Adalimumab and etanercept may...

  9. Aromatase inhibitors in stimulated IVF cycles

    DEFF Research Database (Denmark)

    Papanikolaou, Evangelos G; Polyzos, Nikolaos P; Al Humaidan, Peter Samir Heskjær


    Aromatase inhibitors have been introduced as a new treatment modality that could challenge clomiphene citrate as an ovulation induction regiment in patients with PCOS. Although several randomized trials have been conducted regarding their use as ovulation induction agents, only few trials are ava...

  10. The Glycosylation of Plasminogen Activator Inhibitor-1

    DEFF Research Database (Denmark)

    Skottrup, Peter Durand; Pedersen, Katrine Egelund; Christensen, Anni

    Plasminogen activator inhibitor type-1 (PAI-1) has three potential sites for N-linked glycosylation, including Asn209Tyr210Thr211, Asn265Met266Thr267, and Asn329Glu330Ser331. Using a HEK293 expression system, we have made mutants with Asp or Gln substitutions of the Asn residue in each of these s...

  11. Therapeutic substitution post-patent expiry: the cases of ACE inhibitors and proton pump inhibitors. (United States)

    Vandoros, Sotiris


    This paper examines whether there is a switch in total (originator and generic) consumption after generic entry from molecules that face generic competition towards other molecules of the same class, which are still in-patent. Data from six European countries for the time period 1991 to 2006 are used to study the cases of angiotensin-converting enzyme inhibitors and proton pump inhibitors. Empirical evidence shows that patent expiry of captopril and enalapril led to a switch in total (off-patent originator and generic) consumption towards other in-patent angiotensin-converting enzyme inhibitors, whereas patent expiry of omeprazole led to a switch in consumption towards other proton pump inhibitors. This phenomenon makes generic policies ineffective and results in an increase in pharmaceutical expenditure due to the absence of generic alternatives in the market of in-patent molecules. Copyright © 2013 John Wiley & Sons, Ltd.

  12. ROS inhibitor N-acetyl-l-cysteine antagonizes the activity of proteasome inhibitors (United States)

    Halasi, Marianna; Wang, Ming; Chavan, Tanmay S.; Gaponenko, Vadim; Hay, Nissim; Gartel, Andrei L.


    NAC (N-acetyl-l-cysteine) is commonly used to identify and test ROS (reactive oxygen species) inducers, and to inhibit ROS. In the present study, we identified inhibition of proteasome inhibitors as a novel activity of NAC. Both NAC and catalase, another known scavenger of ROS, similarly inhibited ROS levels and apoptosis associated with H2O2. However, only NAC, and not catalase or another ROS scavenger Trolox, was able to prevent effects linked to proteasome inhibition, such as protein stabilization, apoptosis and accumulation of ubiquitin conjugates. These observations suggest that NAC has a dual activity as an inhibitor of ROS and proteasome inhibitors. Recently, NAC was used as a ROS inhibitor to functionally characterize a novel anticancer compound, piperlongumine, leading to its description as a ROS inducer. In contrast, our own experiments showed that this compound depicts features of proteasome inhibitors including suppression of FOXM1 (Forkhead box protein M1), stabilization of cellular proteins, induction of ROS-independent apoptosis and enhanced accumulation of ubiquitin conjugates. In addition, NAC, but not catalase or Trolox, interfered with the activity of piperlongumine, further supporting that piperlongumine is a proteasome inhibitor. Most importantly, we showed that NAC, but not other ROS scavengers, directly binds to proteasome inhibitors. To our knowledge, NAC is the first known compound that directly interacts with and antagonizes the activity of proteasome inhibitors. Taken together, the findings of the present study suggest that, as a result of the dual nature of NAC, data interpretation might not be straightforward when NAC is utilized as an antioxidant to demonstrate ROS involvement in drug-induced apoptosis. PMID:23772801

  13. Peptidyl cyclopropenones: Reversible inhibitors, irreversible inhibitors, or substrates of cysteine proteases?


    Cohen, Meital; Bretler, Uriel; Albeck, Amnon


    Peptidyl cyclopropenones were previously introduced as selective cysteine protease reversible inhibitors. In the present study we synthesized one such peptidyl cyclopropenone and investigated its interaction with papain, a prototype cysteine protease. A set of kinetics, biochemical, HPLC, MS, and 13C-NMR experiments revealed that the peptidyl cyclopropenone was an irreversible inhibitor of the enzyme, alkylating the catalytic cysteine. In parallel, this cyclopropenone also behaved as an alter...

  14. Environmental life cycle analysis of potato sprout inhibitors

    NARCIS (Netherlands)

    Kerstholt, R.P.V.; Ree, C.M.; Moll, H.C.

    Potato sprout inhibitors are generally applied to suppress sprouting during winter storage. This study presents the compared environmental profiles of the two sprout inhibitors available on the Dutch market: A traditional chemical product with isopropyl-3-chlorophenylcarbamate (CIPC) and

  15. Glycosidase inhibitors: update and perspectives on practical use

    National Research Council Canada - National Science Library

    Asano, Naoki


    .... Since then, over 100 glycosidase inhibitors have been isolated from plants and microorganisms. Modifying or blocking biological processes by specific glycosidase inhibitors has revealed the vital functions of glycosidases in living systems...

  16. Extraction and Characterization of Cathepsin Inhibitor from Milkfish

    Directory of Open Access Journals (Sweden)

    Tati Nurhayati


    Full Text Available Proteolytic enzyme is distributed acros all organism including fish. Cysteine proteases are the largest group of proteolytic enzyme. Lysosomal cathepsin, one of cysteine protease enzyme, cause softening and degradation of myofibril protein and it’s activity is regulated by endogenous inhibitors. The purposes of this study were to optimize the extraction cathepsin inhibitors from the skin, muscles, and viscera of fish, to partially purify the cathepsin inhibitors of selected sources, and to study the characteristics of the cathepsin inhibitor. The cathepsin inhibitor could be extracted from muscle fish and partially purified using ammonium sulfate of 70%. The purified cathepsin inhibitor had optimum temperature at 40°C and the optimum at pH 8. Metal ions decreased the activity of the protease inhibitor, except 1 mM of metal ion Mn2+ and Na+. Keywords: Cathepsin, characterization, partial purification, protease inhibitor

  17. Cellular growth kinetics distinguish a cyclophilin inhibitor from an HSP90 inhibitor as a selective inhibitor of hepatitis C virus.

    Directory of Open Access Journals (Sweden)

    Rudolf K F Beran

    Full Text Available During antiviral drug discovery, it is critical to distinguish molecules that selectively interrupt viral replication from those that reduce virus replication by adversely affecting host cell viability. In this report we investigate the selectivity of inhibitors of the host chaperone proteins cyclophilin A (CypA and heat-shock protein 90 (HSP90 which have each been reported to inhibit replication of hepatitis C virus (HCV. By comparing the toxicity of the HSP90 inhibitor, 17-(Allylamino-17-demethoxygeldanamycin (17-AAG to two known cytostatic compounds, colchicine and gemcitabine, we provide evidence that 17-AAG exerts its antiviral effects indirectly through slowing cell growth. In contrast, a cyclophilin inhibitor, cyclosporin A (CsA, exhibited selective antiviral activity without slowing cell proliferation. Furthermore, we observed that 17-AAG had little antiviral effect in a non-dividing cell-culture model of HCV replication, while CsA reduced HCV titer by more than two orders of magnitude in the same model. The assays we describe here are useful for discriminating selective antivirals from compounds that indirectly affect virus replication by reducing host cell viability or slowing cell growth.

  18. Role of inhibitors and biodegradable material in mitigation of ...

    African Journals Online (AJOL)



    May 2, 2011 ... reduce ammonia volatilization loss from urea fertilizer. Coating with urease inhibitors can improve the bioavailability of N, resulting in increased dry matter yield and N uptake. Such increases result from delayed urea hydrolysis by urease inhibitors and coating materials. The value of inhibitors in mitigating.

  19. Enzyme inhibitors of marine microbial origin with pharmaceutical importance. (United States)

    Imada, Chiaki


    Several enzyme inhibitors with various industrial uses were isolated from bacteria and actinomycetes living in the marine environment. These inhibitors are useful in medicine and agriculture. All the compounds, except the monoamine oxidase inhibitors, are novel, and their activities have been characterized.

  20. Protein C inhibitor may modulate human sperm-oocyte interactions

    NARCIS (Netherlands)

    Elisen, M. G.; van Kooij, R. J.; Nolte, M. A.; Marquart, J. A.; Lock, T. M.; Bouma, B. N.; Meijers, J. C.


    Protein C inhibitor (PCI) is a heparin-binding plasma serine protease inhibitor that was originally identified as an inhibitor of activated protein C. PCI has a broad protease specificity, inhibiting several proteases in hemostasis and fibrinolysis by acting as a suicide substrate. Recently it has

  1. Replacing sulfa drugs with novel DHPS inhibitors. (United States)

    Hammoudeh, Dalia I; Zhao, Ying; White, Stephen W; Lee, Richard E


    More research effort needs to be invested in antimicrobial drug development to address the increasing threat of multidrug-resistant organisms. The enzyme DHPS has been a validated drug target for over 70 years as the target for the highly successful sulfa drugs. The use of sulfa drugs has been compromised by the widespread presence of resistant organisms and the adverse side effects associated with their use. Despite the large amount of structural information available for DHPS, few recent publications address the possibility of using this knowledge for novel drug design. This article reviews the relevant papers and patents that report promising new small-molecule inhibitors of DHPS, and discuss these data in light of new insights into the DHPS catalytic mechanism and recently determined crystal structures of DHPS bound to potent small-molecule inhibitors. This new functional understanding confirms that DHPS deserves further consideration as an antimicrobial drug target.

  2. Raltegravir: first in class HIV integrase inhibitor

    Directory of Open Access Journals (Sweden)

    Zelalem Temesgen


    Full Text Available Zelalem Temesgen1, Dawd S Siraj21Mayo Clinic, Rochester, MN, USA; 2East Carolina University Greenville, NC, USAAbstract: On October 16, 2007, the US Food and Drug Administration (FDA approved raltegravir for treatment of human immunodeficiency virus (HIV-1 infection in combination with other antiretroviral agents in treatment-experienced adult patients who have evidence of viral replication and HIV-1 strains resistant to multiple antiretroviral agents. Raltegravir is first in a novel class of antiretroviral drugs known as integrase inhibitors. It has demonstrated potent anti HIV activity in both antiretroviral treatment-naïve and experienced patients. The most common adverse events reported with raltegravir during phase 2 and 3 clinical trials were diarrhea, nausea, and headache. Laboratory abnormalities include mild elevations in liver transaminases and creatine phosphokinase.Keywords: raltegravir, HIV, antiretroviral agents, integrase inhibitors

  3. Are leukotriene inhibitors useful for bronchiolitis? (United States)

    Pérez-Gutiérrez, Fernanda; Otárola-Escobar, Isidora; Arenas, Deidyland


    Bronchiolitis is a prevalent disease in children under two years of age, which carries significant morbidity and mortality. However, there is controversy regarding the optimal therapeutic management. Leukotriene inhibitors have been proposed as an alternative, although its efficacy is not clear yet. Searching in Epistemonikos database, which is maintained by screening multiple databases, we identified two systematic reviews comprising six trials addressing the question of this article. We extracted data, combined the evidence using meta-analysis and generated a summary of findings following the GRADE approach. We concluded leukotriene inhibitors might not decrease mortality levels on bronchiolitis patients and it is not clear whether they decrease length of hospital stay. They might reduce recurrent wheezing, but the certainty of the evidence is low, and they increase adverse effects.

  4. Potent peptidic fusion inhibitors of influenza virus

    Energy Technology Data Exchange (ETDEWEB)

    Kadam, Rameshwar U.; Juraszek, Jarek; Brandenburg, Boerries; Buyck, Christophe; Schepens, Wim B. G.; Kesteleyn, Bart; Stoops, Bart; Vreeken, Rob J.; Vermond, Jan; Goutier, Wouter; Tang, Chan; Vogels, Ronald; Friesen, Robert H. E.; Goudsmit, Jaap; van Dongen, Maria J. P.; Wilson, Ian A.


    Influenza therapeutics with new targets and mechanisms of action are urgently needed to combat potential pandemics, emerging viruses, and constantly mutating strains in circulation. We report here on the design and structural characterization of potent peptidic inhibitors of influenza hemagglutinin. The peptide design was based on complementarity-determining region loops of human broadly neutralizing antibodies against the hemagglutinin (FI6v3 and CR9114). The optimized peptides exhibit nanomolar affinity and neutralization against influenza A group 1 viruses, including the 2009 H1N1 pandemic and avian H5N1 strains. The peptide inhibitors bind to the highly conserved stem epitope and block the low pH–induced conformational rearrangements associated with membrane fusion. These peptidic compounds and their advantageous biological properties should accelerate the development of new small molecule– and peptide-based therapeutics against influenza virus.

  5. SGLT2 Inhibitors: Benefit/Risk Balance. (United States)

    Scheen, André J


    Inhibitors of sodium-glucose cotransporters type 2 (SGLT2) reduce hyperglycemia by increasing urinary glucose excretion. They have been evaluated in patients with type 2 diabetes treated with diet/exercise, metformin, dual oral therapy or insulin. Three agents are available in Europe and the USA (canagliflozin, dapagliflozin, empagliflozin) and others are commercialized in Japan or in clinical development. SGLT2 inhibitors reduce glycated hemoglobin, with a minimal risk of hypoglycemia. They exert favorable effects beyond glucose control with consistent body weight, blood pressure, and serum uric acid reductions. Empagliflozin showed remarkable reductions in cardiovascular/all-cause mortality and in hospitalization for heart failure in patients with previous cardiovascular disease. Positive renal outcomes were also shown with empagliflozin. Mostly reported adverse events are genital mycotic infections, while urinary tract infections and events linked to volume depletion are rather rare. Concern about a risk of ketoacidosis and bone fractures has been recently raised, which deserves caution and further evaluation.

  6. Rho-kinase inhibitors from adlay seeds. (United States)

    Amen, Yhiya; Zhu, Qinchang; Tran, Hai-Bang; Afifi, Mohamed S; Halim, Ahmed F; Ashour, Ahmed; Fujimoto, Ryoji; Goto, Takahiro; Shimizu, Kuniyoshi


    Rho-kinase enzymes are one of the most important targets recently identified in our bodies. Several lines of evidence indicate that these enzymes are involved in many diseases and cellular disorders. ROCK inhibitors may have clinical applications for cancer, hypertension, glaucoma, etc. Our study aims to identify the possible involvement of Rho-kinase inhibition to the multiple biological activities of adlay seeds and provide a rationale for their folkloric medicines. Hence, we evaluated Rho-kinase I and II inhibitory activity of the ethanol extract and 28 compounds derived from the seeds. A molecular docking assay was designed to estimate the binding affinity of the tested compounds with the target enzymes. The results of our study suggest a possible involvement of Rho-kinase inhibition to the multiple biological activities of the seeds. Furthermore, the results obtained with the tested compounds revealed some interesting skeletons as a scaffold for design and development of natural Rho-kinase inhibitors.

  7. Caffeine as a Potential Quorum Sensing Inhibitor

    Directory of Open Access Journals (Sweden)

    Kok-Gan Chan


    Full Text Available Quorum sensing enables bacteria to control the gene expression in response to the cell density. It regulates a variety of bacterial physiological functions such as biofilm formation, bioluminescence, virulence factors and swarming which has been shown contribute to bacterial pathogenesis. The use of quorum sensing inhibitor would be of particular interest in treating bacterial pathogenicity and infections. In this work, we have tested caffeine as quorum sensing inhibitor by using Chromobacterium violaceum CV026 as a biosensor. We verified that caffeine did not degrade the N-acyl homoserine lactones tested. In this work, it is shown that caffeine could inhibit N-acyl homoserine lactone production and swarming of a human opportunistic pathogen, namely Pseudomonas aeruginosa PA01. To the best of our knowledge, this is the first documentation providing evidence on the presence of anti-quorum sensing activity in caffeine. Our work will allow caffeine to be explored as anti-infective drugs.

  8. Natural products inhibitors of the enzyme acetylcholinesterase

    Directory of Open Access Journals (Sweden)

    José M. Barbosa Filho

    Full Text Available Alzheimer's disease (AD is a progressive, neurodegenerative pathology that primarily affects the elderly population, and is estimated to account for 50-60% of dementia cases in persons over 65 years of age. The main symptoms associated with AD involve cognitive dysfunction, primarily memory loss. Other features associated with the later stages of AD include language deficits, depression, behavioural problems including agitation, mood disturbances and psychosis. One of the most promising approaches for treating this disease is to enhance the acetylcholine level in the brain using acetylcholinesterase (AChE inhibitors. The present work reviews the literature on plants and plant-derived compounds inhibitors of enzyme acetylcholinesterase. The review refers to 309 plant extracts and 260 compounds isolated from plants, which are classified in appropriate chemical groups and model tested, and cites their activity. For this purpose 175 references were consulted.

  9. Inhibitors of the Cellular Trafficking of Ricin

    Directory of Open Access Journals (Sweden)

    Daniel Gillet


    Full Text Available Throughout the last decade, efforts to identify and develop effective inhibitors of the ricin toxin have focused on targeting its N-glycosidase activity. Alternatively, molecules disrupting intracellular trafficking have been shown to block ricin toxicity. Several research teams have recently developed high-throughput phenotypic screens for small molecules acting on the intracellular targets required for entry of ricin into cells. These screens have identified inhibitory compounds that can protect cells, and sometimes even animals against ricin. We review these newly discovered cellular inhibitors of ricin intoxication, discuss the advantages and drawbacks of chemical-genetics approaches, and address the issues to be resolved so that the therapeutic development of these small-molecule compounds can progress.

  10. Cathepsin D inactivates cysteine proteinase inhibitors, cystatins. (United States)

    Lenarcic, B; Kos, J; Dolenc, I; Lucovnik, P; Krizaj, I; Turk, V


    The formation of inactive complexes in excess molar amounts of human cathepsins H and L with their protein inhibitors human stefin A, human stefin B and chicken cystatin at pH 5.6 has been shown by measurement of enzyme activity coupled with reverse-phase HPLC not to involve covalent cleavage of the inhibitors. Inhibition must be the direct result of binding. On the contrary the interaction of cystatins with aspartic proteinase cathepsin D at pH 3.5 for 60 min followed by HPLC resulted in their inactivation accompanied by peptide bond cleavage at several sites, preferentially those involving hydrophobic amino acid residues. The released peptides do not inhibit papain and cathepsin L. These results explain reported elevated levels of cysteine proteinases and lead to the proposal that cathepsin D exerts an important function, through inactivation of cystatins, in the increased activities of cysteine proteinases in human diseases including muscular distrophy.

  11. Classification of Cytochrome P450 1A2 Inhibitors and Non-Inhibitors by Machine Learning Techniques

    DEFF Research Database (Denmark)

    Vasanthanathan, Poongavanam; Taboureau, Olivier; Oostenbrink, Chris


    of CYP1A2 inhibitors and non-inhibitors. Training and test sets consisted of about 400 and 7000 compounds, respectively. Various machine learning techniques, like binary QSAR, support vector machine (SVM), random forest, kappa nearest neighbors (kNN), and decision tree methods were used to develop...... to be applicable for virtual screening of CYP1A2 inhibitors or non-inhibitors, or can be used as simple filters in the drug discovery process....

  12. Immune checkpoint inhibitor-related myocarditis. (United States)

    Tajiri, Kazuko; Aonuma, Kazutaka; Sekine, Ikuo


    Immune checkpoint inhibitors have demonstrated significant clinical benefit in many cancers. The clinical benefit afforded by these treatments can be accompanied by a unique and distinct spectrum of adverse events. Recently, several fatal cases of immune checkpoint inhibitor-related myocarditis were reported. Although its frequency is comparatively lower than that of other immune-related adverse events, myocarditis can lead to circulatory collapse and lethal ventricular arrhythmia. Immune checkpoints, cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed cell death protein 1 (PD-1), play important roles in establishing peripheral tolerance to the heart. Evidence from studies using genetically engineered mouse models suggests that CTLA-4 signaling terminates proliferation and promotes anergy during the primary response to cardiac self-peptide recognition. PD-1 signaling restrains autoreactive T cells that enter the peripheral tissues and recognize cardiac-peptide, maintaining them in an anergic state. Patients affected by immune checkpoint inhibitor-related myocarditis often experience rapid onset of profound hemodynamic compromise progressing to cardiogenic shock. Early diagnosis is mandatory to address specific therapy and correct the timing of circulatory support. However, the diagnosis of myocarditis is challenging due to the heterogeneity of clinical presentations. Owing to its early onset, nonspecific symptomatology and fulminant progression, especially when these drugs are used in combination, oncologists should be vigilant for immune checkpoint inhibitor-related myocarditis. With many questions yet to be answered, from basic immune biology to clinical management, future research should aim to optimize the use of these drugs by identifying predictive biomarkers of either a response to therapy or the risks of myocarditis development. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail:

  13. Acrosin inhibitor detecting along the boar epididymis

    Czech Academy of Sciences Publication Activity Database

    Maňásková-Postlerová, Pavla; Cozlová, Nina; Dorosh, Andriy; Šulc, Miroslav; Guyonet, B.; Jonáková, Věra


    Roč. 82, Jan 2016 (2016), s. 733-739 ISSN 0141-8130 R&D Projects: GA ČR(CZ) GAP503/12/1834; GA MŠk(CZ) ED1.1.00/02.0109; GA ČR GA14-05547S Institutional support: RVO:86652036 ; RVO:61388971 Keywords : Acrosin inhibitor * Boar epididymis * Spermatozoa Subject RIV: CE - Biochemistry Impact factor: 3.671, year: 2016

  14. BCR ABL Kinase Inhibitors for Cancer Therapy


    Dhara Patel; Maulik P. Suthar; Vipul Patel; Rajesh Singh


    BCR-ABL tyrosine kinase inhibitors have started era of molecular targeted therapy and marked a greatest milestone in cancer drug discovery. Despite of impressive cytogenetic response rates achieved with several agents in patients with chronic myelogenous leukemia (CML) in chronic phase, those with advanced stage CML frequently obtain more modest responses that are in many instances of short duration. Several mechanisms of resistance to imatinib are also observed among patients that develop cl...

  15. Adverse Effects of COX-2 Inhibitors

    Directory of Open Access Journals (Sweden)

    Jagdish N. Sharma


    Full Text Available Cyclooxygenase-2 selective inhibitors (COXIBs were developed with the prime object of minimizing gastrointestinal adverse effects, which are seen with the use of traditional nonsteroidal anti-inflammatory drugs (NSAIDs. Their long-term use is limited by the development of hypertension, edema, and congestive heart failure in a significant proportion of patients. NSAIDs block the activity of both COX isozymes, COX-1 and COX-2, which mediate the enzymatic conversion of arachidonate to prostaglandin H2 (PGH2 and other prostaglandin (PG metabolites. It is well established that the cardiovascular profile of COX-2 inhibitors can be accounted for by inhibition of COX-dependent PG synthesis. Following the COX-mediated synthesis of PGH2 from arachidonate, PGH2 is metabolized to one of at least five bioactive PGs, including PGE2, PGI2, PGF2, PGD2, or thromboxane A2 (TXA2. These prostanoids have pleiotropic cardiovascular effects, altering platelet function and renal function, and they are acting either as vasodilators or vasoconstrictors. Although COX-1 and COX-2 exhibit similar biochemical activity in converting arachidonate to PGH2in vitro, the ultimate prostanoids they produce in vivo may be different due to differential regulation of COX-1 and COX-2, tissue distribution, and availability of the prostanoid synthases. PGs have been established as being critically involved in mitigating hypertension, helping to maintain medullary blood flow (MBF, promoting urinary salt excretion, and preserving the normal homeostasis of thrombosis, and the researchers found that the use of COX-2 inhibitors caused many serious complications in altering the normal body homeostasis. The purpose of the present research is to explain briefly the side effects of COX-2 inhibitors on the renal and cardiovascular system.

  16. Morphology and Mechanism of Benign Inhibitors (United States)


    University of Cincinnati. Samples were mounted and coated with 2–3 nm of tungsten using a dual ion beam sputter coater (South Bay Technologies, Inc.) to...inhibitor precursor solution on the metal surface for 30 s, the wafer is accelerated to 2000 rpm and held for 1 minute to spin off the excess solution. To...24 hours before further characterization. The coating procedure was carried out using a Laurell single-wafer spin processor (WS-400A-6NPP-Lite

  17. Corrosion protection with eco-friendly inhibitors (United States)

    Shahid, Muhammad


    Corrosion occurs as a result of the interaction of a metal with its environment. The extent of corrosion depends on the type of metal, the existing conditions in the environment and the type of aggressive ions present in the medium. For example, CO3-2 and NO-3 produce an insoluble deposit on the surface of iron, resulting in the isolation of metal and consequent decrease of corrosion. On the other hand, halide ions are adsorbed selectively on the metal surface and prevent formation of the oxide phase on the metal surface, resulting in continuous corrosion. Iron, aluminum and their alloys are widely used, both domestically and industrially. Linear alkylbenzene and linear alkylbenzene sulfonate are commonly used as detergents. They have also been found together in waste water. It is claimed that these chemicals act as inhibitors for stainless steel and aluminum. Release of toxic gases as a result of corrosion in pipelines may lead in certain cases to air pollution and possible health hazards. Therefore, there are two ways to look at the relationship between corrosion and pollution: (i) corrosion of metals and alloys due to environmental pollution and (ii) environmental pollution as a result of corrosion protection. This paper encompasses the two scenarios and possible remedies for various cases, using 'green' inhibitors obtained either from plant extracts or from pharmaceutical compounds. In the present study, the effect of piperacillin sodium as a corrosion inhibitor for mild steel was investigated using a weight-loss method as well as a three-electrode dc electrochemical technique. It was found that the corrosion rate decreased as the concentration of the inhibitor increased up to 9×10-4 M 93% efficiency was exhibited at this concentration.

  18. FAITH - Fast Assembly Inhibitor Test for HIV

    Czech Academy of Sciences Publication Activity Database

    Hadravová, Romana; Rumlová, Michaela; Ruml, T.


    Roč. 486, Dec (2015), s. 78-87 ISSN 0042-6822 R&D Projects: GA ČR(CZ) GA14-15326S; GA MŠk LO1302; GA MŠk(CZ) LO1304 Institutional support: RVO:61388963 Keywords : retrovirus * HIV * assembly * assay * inhibitor Subject RIV: EE - Microbiology, Virology Impact factor: 3.200, year: 2015

  19. Identification of Neutrophil Exocytosis Inhibitors (Nexinhibs), Small Molecule Inhibitors of Neutrophil Exocytosis and Inflammation (United States)

    Johnson, Jennifer L.; Ramadass, Mahalakshmi; He, Jing; Brown, Steven J.; Zhang, Jinzhong; Abgaryan, Lusine; Biris, Nikolaos; Gavathiotis, Evripidis; Rosen, Hugh; Catz, Sergio D.


    Neutrophils constitute the first line of cellular defense in response to bacterial and fungal infections and rely on granular proteins to kill microorganisms, but uncontrolled secretion of neutrophil cargos is injurious to the host and should be closely regulated. Thus, increased plasma levels of neutrophil secretory proteins, including myeloperoxidase and elastase, are associated with tissue damage and are hallmarks of systemic inflammation. Here, we describe a novel high-throughput screening approach to identify small molecule inhibitors of the interaction between the small GTPase Rab27a and its effector JFC1, two central regulators of neutrophil exocytosis. Using this assay, we have identified small molecule inhibitors of Rab27a-JFC1 binding that were also active in cell-based neutrophil-specific exocytosis assays, demonstrating the druggability of Rab GTPases and their effectors. These compounds, named Nexinhibs (neutrophil exocytosis inhibitors), inhibit exocytosis of azurophilic granules in human neutrophils without affecting other important innate immune responses, including phagocytosis and neutrophil extracellular trap production. Furthermore, the compounds are reversible and potent inhibitors of the extracellular production of superoxide anion by preventing the up-regulation of the granule membrane-associated subunit of the NADPH oxidase at the plasma membrane. Nexinhibs also inhibit the up-regulation of activation signature molecules, including the adhesion molecules CD11b and CD66b. Importantly, by using a mouse model of endotoxin-induced systemic inflammation, we show that these inhibitors have significant activity in vivo manifested by decreased plasma levels of neutrophil secretory proteins and significantly decreased tissue infiltration by inflammatory neutrophils. Altogether, our data present the first neutrophil exocytosis-specific inhibitor with in vivo anti-inflammatory activity, supporting its potential use as an inhibitor of systemic

  20. Emicizumab Prophylaxis in Hemophilia A with Inhibitors. (United States)

    Oldenburg, Johannes; Mahlangu, Johnny N; Kim, Benjamin; Schmitt, Christophe; Callaghan, Michael U; Young, Guy; Santagostino, Elena; Kruse-Jarres, Rebecca; Negrier, Claude; Kessler, Craig; Valente, Nancy; Asikanius, Elina; Levy, Gallia G; Windyga, Jerzy; Shima, Midori


    Emicizumab (ACE910) bridges activated factor IX and factor X to restore the function of activated factor VIII, which is deficient in persons with hemophilia A. This phase 3, multicenter trial assessed once-weekly subcutaneous emicizumab prophylaxis in persons with hemophilia A with factor VIII inhibitors. We enrolled participants who were 12 years of age or older. Those who had previously received episodic treatment with bypassing agents were randomly assigned in a 2:1 ratio to emicizumab prophylaxis (group A) or no prophylaxis (group B). The primary end point was the difference in bleeding rates between group A and group B. Participants who had previously received prophylactic treatment with bypassing agents received emicizumab prophylaxis in group C. A total of 109 male participants with hemophilia A with inhibitors were enrolled. The annualized bleeding rate was 2.9 events (95% confidence interval [CI], 1.7 to 5.0) among participants who were randomly assigned to emicizumab prophylaxis (group A, 35 participants) versus 23.3 events (95% CI, 12.3 to 43.9) among those assigned to no prophylaxis (group B, 18 participants), representing a significant difference of 87% in favor of emicizumab prophylaxis (Phemophilia A with inhibitors. (Funded by F. Hoffmann-La Roche and Chugai Pharmaceutical; HAVEN 1 number, NCT02622321 .).

  1. Therapeutic Innovations: Tyrosine Kinase Inhibitors in Cancer

    Directory of Open Access Journals (Sweden)

    Nikolaos Dervisis


    Full Text Available Conventional cytotoxic chemotherapy involving DNA-interacting agents and indiscriminate cell death is no longer the future of cancer management. While chemotherapy is not likely to completely disappear from the armamentarium; the use of targeted therapies in combination with conventional treatment is becoming the standard of care in human medicine. Tyrosine kinases are pivotal points of functional cellular pathways and have been implicated in malignancy, inflammatory, and immune-mediated diseases. Pharmaceutical interventions targeting aberrant tyrosine kinase signaling has exploded and is the second most important area of drug development. The “Valley of Death” between drug discovery and approval threatens to blunt the enormous strides in cancer management seen thus far. Kinase inhibitors, as targeted small molecules, hold promise in the treatment and diagnosis of cancer. However, there are still many unanswered questions regarding the use of kinase inhibitors in the interpretation and management of cancer. Comparative oncology has the potential to address restrictions and limitations in the advancement in kinase inhibitor therapy.

  2. Modelling of potentially promising SARS protease inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Plewczynski, Dariusz [Interdisciplinary Centre for Mathematical and Computational Modelling, ICM, Warsaw University, Pawinskiego 5a Street, 02-106 Warsaw (Poland); Hoffmann, Marcin [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Grotthuss, Marcin von [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Knizewski, Lukasz [Interdisciplinary Centre for Mathematical and Computational Modelling, ICM, Warsaw University, Pawinskiego 5a Street, 02-106 Warsaw (Poland); Rychewski, Leszek [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Eitner, Krystian [BioInfoBank Institute, Limanowskiego 24A/16, 60-744 Poznan (Poland); Ginalski, Krzysztof [Interdisciplinary Centre for Mathematical and Computational Modelling, ICM, Warsaw University, Pawinskiego 5a Street, 02-106 Warsaw (Poland)


    In many cases, at the beginning of a high throughput screening experiment some information about active molecules is already available. Active compounds (such as substrate analogues, natural products and inhibitors of related proteins) are often identified in low throughput validation studies on a biochemical target. Sometimes the additional structural information is also available from crystallographic studies on protein and ligand complexes. In addition, the structural or sequence similarity of various protein targets yields a novel possibility for drug discovery. Co-crystallized compounds from homologous proteins can be used to design leads for a new target without co-crystallized ligands. In this paper we evaluate how far such an approach can be used in a real drug campaign, with severe acute respiratory syndrome (SARS) coronavirus providing an example. Our method is able to construct small molecules as plausible inhibitors solely on the basis of the set of ligands from crystallized complexes of a protein target, and other proteins from its structurally homologous family. The accuracy and sensitivity of the method are estimated here by the subsequent use of an electronic high throughput screening flexible docking algorithm. The best performing ligands are then used for a very restrictive similarity search for potential inhibitors of the SARS protease within the million compounds from the Ligand.Info small molecule meta-database. The selected molecules can be passed on for further experimental validation.

  3. Model for metabolic resistance against ALS inhibitors

    Directory of Open Access Journals (Sweden)

    Richter, Otto


    Full Text Available Due to herbicide selection pressure metabolic resistance has evolved in many weed species. In this paper we analyse the interaction between the branched chain amino acid (BBC pathway and detoxifying pathways for herbicide breakdown. The four phase detoxification pathway of herbicides comprising the action of P450, GST, glycosyltransferase and ABC transporter is modelled by a system of coupled enzyme kinetic reactions represented by nonlinear differential equations. The herbicide under consideration inhibits the enzyme ALS, which is the key enzyme for the biosynthesis of branched amino acids. For the kinetics of ALS a Monod approach is employed with a binding site for the inhibitor. Synthetic and detoxification pathways are coupled. The model is used to study the production of branched amino acids under the action of ALS inhibitors for different structures and modes of action of the detoxification pathway. The model is capable of generating typical dose response curves and their shift in dependence of the activity pattern of the enzymes of the detoxification pathway of the inhibitor.

  4. The most abundant protease inhibitor in potato tuber (Cv. Elkana) is a serine protease inhibitor from the Kunitz Family.

    NARCIS (Netherlands)

    Pouvreau, L.A.M.; Gruppen, H.; Koningsveld, van G.A.; Broek, van den L.A.M.; Voragen, A.G.J.


    The gene of the most abundant protease inhibitor in potato cv. Elkana was isolated and sequenced. The deduced amino acid sequence of this gene showed 98% identity with potato serine protease inhibitor (PSPI), a member of the Kunitz family. Therefore, the most abundant protease inhibitor was

  5. Structure-Based Search for New Inhibitors of Cholinesterases

    Directory of Open Access Journals (Sweden)

    Barbara Malawska


    Full Text Available Cholinesterases are important biological targets responsible for regulation of cholinergic transmission, and their inhibitors are used for the treatment of Alzheimer’s disease. To design new cholinesterase inhibitors, of different structure-based design strategies was followed, including the modification of compounds from a previously developed library and a fragment-based design approach. This led to the selection of heterodimeric structures as potential inhibitors. Synthesis and biological evaluation of selected candidates confirmed that the designed compounds were acetylcholinesterase inhibitors with IC50 values in the mid-nanomolar to low micromolar range, and some of them were also butyrylcholinesterase inhibitors.

  6. Pathophysiological significance and therapeutic applications of snake venom protease inhibitors. (United States)

    Thakur, Rupamoni; Mukherjee, Ashis K


    Protease inhibitors are important constituents of snake venom and play important roles in the pathophysiology of snakebite. Recently, research on snake venom protease inhibitors has provided valuable information to decipher the molecular details of various biological processes and offer insight for the development of some therapeutically important molecules from snake venom. The process of blood coagulation and fibrinolysis, in addition to affecting platelet function, are well known as the major targets of several snake venom protease inhibitors. This review summarizes the structure-functional aspects of snake venom protease inhibitors that have been described to date. Because diverse biological functions have been demonstrated by protease inhibitors, a comparative overview of their pharmacological and pathophysiological properties is also highlighted. In addition, since most snake venom protease inhibitors are non-toxic on their own, this review evaluates the different roles of individual protease inhibitors that could lead to the identification of drug candidates and diagnostic molecules. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. xtraction and Characterization of Cathepsin Inhibitor from Milkfish

    Directory of Open Access Journals (Sweden)

    Tati Nurhayati


    Full Text Available Abstract Proteolytic enzyme is distributed acros all organism including fish. Cysteine proteases are the largest group of proteolytic enzyme. Lysosomal cathepsin, one of cysteine protease enzyme, cause softening and degradation of myofibril protein and it’s activity is regulated by endogenous inhibitors. The purposes of this study were to optimize the extraction cathepsin inhibitors from the skin, muscles, and viscera of fish, to partially purify the cathepsin inhibitors of selected sources, and to study the characteristics of the cathepsin inhibitor. The cathepsin inhibitor could be extracted from muscle fish and partially purified using ammonium sulfate of 70%. The purified cathepsin inhibitor had optimum temperature at 40°C and the optimum at pH 8. Metal ions decreased the activity of the protease inhibitor, except 1 mM of metal ion Mn2+ and Na+.

  8. Evaluation of Encapsulated Inhibitor for Autonomous Corrosion Protection (United States)

    Johnsey, M. N.; Li, W.; Buhrow, J. W.; Calle, L. M.; Pearman, B. P.; Zhang, X.


    This work concerns the development of smart coating technologies based on microencapsulation for the autonomous control of corrosion. Microencapsulation allows the incorporation of corrosion inhibitors into coating which provides protection through corrosion-controlled release of these inhibitors.One critical aspect of a corrosion protective smart coating is the selection of corrosion inhibitor for encapsulation and comparison of the inhibitor function before and after encapsulation. For this purpose, a systematic approach is being used to evaluate free and encapsulated corrosion inhibitors by salt immersion. Visual, optical microscope, and Scanning Electron Microscope (with low-angle backscatter electron detector) are used to evaluate these inhibitors. It has been found that the combination of different characterization tools provide an effective method for evaluation of early stage localized corrosion and the effectiveness of corrosion inhibitors.

  9. The "SWOT" of BRAF inhibition in melanoma: RAF inhibitors, MEK inhibitors or both? (United States)

    Nissan, Moriah H; Solit, David B


    Activating mutations in the BRAF gene are among the most prevalent kinase mutations in human cancer. BRAF mutations are most frequent in patients with melanoma where they occur in approximately 50% of patients with advanced disease. Remarkable clinical activity has recently been reported with highly selective RAF inhibitors in melanoma patients whose tumors harbor V600E BRAF mutations. The response rates of RAF inhibitors in patients with BRAF-mutant melanomas far exceed the activity level of any prior therapy studied in this disease. The results suggest that we have entered an era of personalized therapy for patients with metastatic melanoma in which treatment selection will be guided by BRAF mutational status. This review will discuss the strengths, weaknesses, opportunities and threats ("SWOT") of developing RAF and MEK selective inhibitors as anti-cancer therapies, recent insights into the mechanisms of intrinsic and acquired resistance to these agents, and current efforts to develop mechanism-based combination therapies.

  10. F8 haplotype and inhibitor risk: results from the Hemophilia Inhibitor Genetics Study (HIGS) Combined Cohort (United States)

    Schwarz, John; Astermark, Jan; Menius, Erika D.; Carrington, Mary; Donfield, Sharyne M.; Gomperts, Edward D.; Nelson, George W.; Oldenburg, Johannes; Pavlova, Anna; Shapiro, Amy D.; Winkler, Cheryl A.; Berntorp, Erik


    Background Ancestral background, specifically African descent, confers higher risk for development of inhibitory antibodies to factor VIII (FVIII) in hemophilia A. It has been suggested that differences in the distribution of factor VIII gene (F8) haplotypes, and mismatch between endogenous F8 haplotypes and those comprising products used for treatment could contribute to risk. Design and Methods Data from the HIGS Combined Cohort were used to determine the association between F8 haplotype 3 (H3) vs. haplotypes 1 and 2 (H1+H2) and inhibitor risk among individuals of genetically-determined African descent. Other variables known to affect inhibitor risk including type of F8 mutation and HLA were included in the analysis. A second research question regarding risk related to mismatch in endogenous F8 haplotype and recombinant FVIII products used for treatment was addressed. Results H3 was associated with higher inhibitor risk among those genetically-identified (N=49) as of African ancestry, but the association did not remain significant after adjustment for F8 mutation type and the HLA variables. Among subjects of all racial ancestries enrolled in HIGS who reported early use of recombinant products (N=223), mismatch in endogenous haplotype and the FVIII proteins constituting the products used did not confer greater risk for inhibitor development. Conclusion H3 was not an independent predictor of inhibitor risk. Further, our findings did not support a higher risk of inhibitors in the presence of a haplotype mismatch between the FVIII molecule infused and that of the individual. PMID:22958194

  11. Corrosion inhibitor and method of use

    Energy Technology Data Exchange (ETDEWEB)

    Williams, D.A.; Holifield, P.K.; Looney, J.R.; McDougall, L.A.


    This paper discusses a corrosion inhibitor formulation capable of dispersion in aqueous well treating acids. It comprises from 1 to 25 wt % of a metal salt wherein the metal thereof is selected from the group consisting of Cu{sup +}, Sn, Zn, and a Group IIA metal having an atomic number from 12 to 56, a Group IVA metal having an atomic number of 22 or 40, a Group IIIB metal having an atomic number from 13 to 49, a Group VIA metal having an atomic number from 24 to 74, and a Group VB metal having an atomic number from 33 to 83; and mixtures thereof; from 3 to 50 wt% of a quaternary ammonium compound capable of forming a complex with the metal salt; sufficient amount of a highly polar aprotic solvent to dissolve the metal salt and the quaternary ammonium compounds, the concentration of the polar aprotic solvent being between 20 to 90 wt %; and from 1 to 15% of an organic amine dispersant for dispersing the complex of the quaternary ammonium compound and the metal salt in the sell treating acid, the wt % being based on the formulation. This patent also describes a method of acidizing a subterranean formation by injecting a well treating acid solution down pipe into the well. It comprises preparing the corrosion inhibitor formulation of claim 1; dispersing the formulation in the well treating acid solution to provide the solution with at least 0.08 wt % of the metal salt based on the combined weight of the well treating acid and formulation, and injecting the well treating acid solution containing the corrosion inhibitor formulation through the pipe into the formation.

  12. Kynurenine Aminotransferase Isozyme Inhibitors: A Review

    Directory of Open Access Journals (Sweden)

    Alireza Nematollahi


    Full Text Available Kynurenine aminotransferase isozymes (KATs 1–4 are members of the pyridoxal-5’-phosphate (PLP-dependent enzyme family, which catalyse the permanent conversion of l-kynurenine (l-KYN to kynurenic acid (KYNA, a known neuroactive agent. As KATs are found in the mammalian brain and have key roles in the kynurenine pathway, involved in different categories of central nervous system (CNS diseases, the KATs are prominent targets in the quest to treat neurodegenerative and cognitive impairment disorders. Recent studies suggest that inhibiting these enzymes would produce effects beneficial to patients with these conditions, as abnormally high levels of KYNA are observed. KAT-1 and KAT-3 share the highest sequence similarity of the isozymes in this family, and their active site pockets are also similar. Importantly, KAT-2 has the major role of kynurenic acid production (70% in the human brain, and it is considered therefore that suitable inhibition of this isozyme would be most effective in managing major aspects of CNS diseases. Human KAT-2 inhibitors have been developed, but the most potent of them, chosen for further investigations, did not proceed in clinical studies due to the cross toxicity caused by their irreversible interaction with PLP, the required cofactor of the KAT isozymes, and any other PLP-dependent enzymes. As a consequence of the possibility of extensive undesirable adverse effects, it is also important to pursue KAT inhibitors that reversibly inhibit KATs and to include a strategy that seeks compounds likely to achieve substantial interaction with regions of the active site other than the PLP. The main purpose of this treatise is to review the recent developments with the inhibitors of KAT isozymes. This treatise also includes analyses of their crystallographic structures in complex with this enzyme family, which provides further insight for researchers in this and related studies.

  13. The Epidemiology of FVIII Inhibitors in Indian Haemophilia A Patients. (United States)

    Pinto, Patricia; Shelar, Tejashree; Nawadkar, Vidhya; Mirgal, Darshana; Mukaddam, Alfiya; Nair, Preethi; Kasatkar, Priyanka; Gaikwad, Tejasvita; Ali, Shahnaz; Jadli, Anshul; Patil, Rucha; Parihar, Anita; Shanbhag, Sharda; Kulkarni, Bipin; Ghosh, Kanjaksha; Shetty, Shrimati


    A serious complication of replacement therapy in patients with bleeding disorders is the development of 'inhibitors', particularly FVIII inhibitors in haemophilia A patients. This leads to an increase in the management cost, morbidity and mortality, especially post-operatively. The mechanism of FVIII inhibitor development is quite complex and it is difficult to predict inhibitor development, but a prompt and accurate diagnosis is critical as early therapy can save lives. The aim of this study was to screen patients with bleeding disorders in India for inhibitors, and to analyse and compare the prevalence of inhibitors in different regions in India. Patient details were recorded and blood samples were collected in sodium citrate vacutainers from 1,505 patients with bleeding disorders, in different cities in India. Coagulation and inhibitor screening assays were performed, followed by the Bethesda assay in inhibitor positive samples to quantify the FVIII inhibitor titre. Out of the 1,505 samples analysed, 1,285 were Haemophilia A patients, out of which 78 (6.07 %) were positive for 'FVIII Inhibitors'. The highest incidence of FVIII Inhibitors was seen in South India (13.04 %). The highest incidence of 20.99 % was observed in Chennai, followed by Hyderabad (13.33 %), Jammu (9.90 %) and Guwahati (8.51 %), respectively, with respect to the samples analysed. The other regions showed an inhibitor incidence <8 %. The incidence of inhibitors in haemophilia A patients is different in different regions of India; this may be due to the intensity of treatment, type of product or the genetic characteristics of these patients.

  14. Understanding the mechanisms of aromatase inhibitor resistance. (United States)

    Miller, William R; Larionov, Alexey A


    Aromatase inhibitors (AIs) have a central role in the treatment of breast cancer; however, resistance is a major obstacle to optimal management. Evidence from endocrine, molecular and pathological measurements in clinical material taken before and after therapy with AIs and data from clinical trials in which AIs have been given as treatment either alone or in combination with other targeted agents suggest diverse causes for resistance. These include inherent tumour insensitivity to oestrogen, ineffective inhibition of aromatase, sources of oestrogenic hormones independent of aromatase, activation of signalling by non-endocrine pathways, enhanced cell survival and selection of hormone-insensitive cellular clones during treatment.

  15. Checkpoint inhibitors: a cutting edge in oncology. (United States)

    Jago, C


    The checkpoint inhibitor field, and indeed the whole of immuno-oncology, is fast-paced and fascinating, with huge clinical and commercial potential. The challenge in the coming years will be to define the best type and combination of immunotherapy, and the best target population to receive it. Keytruda's ground-breaking approval for a biomarker-based rather than location-based indication is a solid step in this direction, and is likely to be followed by other such approvals. As the field develops, it is to be hoped that immuno-oncology therapeutics will continue to deliver the significant improvements in patient outcome that have been seen so far.

  16. A New Urease Inhibitor from Viola betonicifolia

    Directory of Open Access Journals (Sweden)

    Naveed Muhammad


    Full Text Available Urease has attracted much attention, as it is directly involved in the formation of infection stones and contributes to the pathogenesis of urolithiasis, pyelonephritis, ammonia and hepatic encephalopathy, hepatic coma and urinary catheter encrustation. Moreover, urease is the major cause of pathologies induced by H. pylori, such as gastritis and peptic ulcer. In the present work, the new natural compound, 3-methoxydalbergione, was isolated from Viola betonicifolia. A mechanistic study of this compound as a natural urease inhibitor was performed by using enzyme kinetics and docking studies. 3-Methoxydalbergione could be considered as a lead molecule for drugs useful in the urease associated diseases.

  17. Protease inhibitors targeting coronavirus and filovirus entry. (United States)

    Zhou, Yanchen; Vedantham, Punitha; Lu, Kai; Agudelo, Juliet; Carrion, Ricardo; Nunneley, Jerritt W; Barnard, Dale; Pöhlmann, Stefan; McKerrow, James H; Renslo, Adam R; Simmons, Graham


    In order to gain entry into cells, diverse viruses, including Ebola virus, SARS-coronavirus and the emerging MERS-coronavirus, depend on activation of their envelope glycoproteins by host cell proteases. The respective enzymes are thus excellent targets for antiviral intervention. In cell culture, activation of Ebola virus, as well as SARS- and MERS-coronavirus can be accomplished by the endosomal cysteine proteases, cathepsin L (CTSL) and cathepsin B (CTSB). In addition, SARS- and MERS-coronavirus can use serine proteases localized at the cell surface, for their activation. However, it is currently unclear which protease(s) facilitate viral spread in the infected host. We report here that the cysteine protease inhibitor K11777, ((2S)-N-[(1E,3S)-1-(benzenesulfonyl)-5-phenylpent-1-en-3-yl]-2-{[(E)-4-methylpiperazine-1-carbonyl]amino}-3-phenylpropanamide) and closely-related vinylsulfones act as broad-spectrum antivirals by targeting cathepsin-mediated cell entry. K11777 is already in advanced stages of development for a number of parasitic diseases, such as Chagas disease, and has proven to be safe and effective in a range of animal models. K11777 inhibition of SARS-CoV and Ebola virus entry was observed in the sub-nanomolar range. In order to assess whether cysteine or serine proteases promote viral spread in the host, we compared the antiviral activity of an optimized K11777-derivative with that of camostat, an inhibitor of TMPRSS2 and related serine proteases. Employing a pathogenic animal model of SARS-CoV infection, we demonstrated that viral spread and pathogenesis of SARS-CoV is driven by serine rather than cysteine proteases and can be effectively prevented by camostat. Camostat has been clinically used to treat chronic pancreatitis, and thus represents an exciting potential therapeutic for respiratory coronavirus infections. Our results indicate that camostat, or similar serine protease inhibitors, might be an effective option for treatment of SARS and

  18. Inhibitors of unactivated p38 MAP kinase. (United States)

    Bullington, James; Argentieri, Dennis; Averill, Kristin; Carter, Demetrius; Cavender, Druie; Fahmy, Bohumila; Fan, Xiaodong; Hall, Daniel; Heintzelman, Geoffrey; Jackson, Paul; Leung, Wai-Ping; Li, Xun; Ling, Ping; Olini, Gilbert; Razler, Thomas; Reuman, Michael; Rupert, Kenneth; Russell, Ronald; Siekierka, John; Wadsworth, Scott; Wolff, Russell; Xiang, Bangping; Zhang, Yue-Mei


    Inhibition of the p38 map kinase pathway has been shown to be beneficial in the treatment of inflammatory diseases. The first class of potent p38 kinase inhibitors was the pyridinylimidazole compounds from SKB. Since then several pyridinylimidazole-based compounds have been shown to inhibit activated p38 kinase in vitro and in vivo. We have developed a novel series of pyridinylimidazole-based compounds, which potently inhibit the p38 pathway by binding to unactivated p38 kinase and only weakly inhibiting activated p38 kinase activity in vitro.

  19. Proton pump inhibitors inhibit pancreatic secretion

    DEFF Research Database (Denmark)

    Wang, Jing; Barbuskaite, Dagne; Tozzi, Marco


    +/K+-ATPases are expressed and functional in human pancreatic ducts and whether proton pump inhibitors (PPIs) have effect on those. Here we show that the gastric HKα1 and HKβ subunits (ATP4A; ATP4B) and non-gastric HKα2 subunits (ATP12A) of H+/K+-ATPases are expressed in human pancreatic cells. Pumps have similar...... localizations in duct cell monolayers (Capan-1) and human pancreas, and notably the gastric pumps are localized on the luminal membranes. In Capan-1 cells, PPIs inhibited recovery of intracellular pH from acidosis. Furthermore, in rats treated with PPIs, pancreatic secretion was inhibited but concentrations...

  20. Tyrosine Kinase Inhibitors and Proton Pump Inhibitors : An Evaluation of Treatment Options

    NARCIS (Netherlands)

    van Leeuwen, Roelof W. F.; Jansman, Frank G. A.; Hunfeld, Nicole G.; Peric, Robert; Reyners, Anna K. L.; Imholz, Alex L. T.; Brouwers, Jacobus R. B. J.; Aerts, Joachim G.; van Gelder, Teun; Mathijssen, Ron H. J.

    Tyrosine kinase inhibitors (TKIs) have rapidly become an established factor in oncology, and have been shown to be effective in a wide variety of solid and hematologic malignancies. Use of the oral administration route of TKIs offers flexibility and is convenient for the patient; however, despite

  1. Aromatase inhibitors in early breast cancer treatment. (United States)

    Mauriac, Louis; Smith, Ian


    A recent National Institutes of Health consensus guideline recommends the general use of adjuvant hormonal therapy for the treatment of early breast cancer in postmenopausal women with estrogen receptor-positive tumors. Standard therapy has been 5 years of tamoxifen, but about 30% of those patients fail to survive 10 years, many as a consequence of tamoxifen resistance. Promising results with the third-generation aromatase inhibitors anastrozole, letrozole, and exemestane in first- and second-line treatment of metastatic breast cancer has prompted their evaluation as adjuvant therapy in patients progressing on tamoxifen or as alternative first-line treatment. Anastrozole has recently achieved significantly longer disease-free survival than tamoxifen in a first-line adjuvant therapy trial, and letrozole is being investigated in several large adjuvant trials. Aromatase inhibitors appear to be well tolerated for long-term adjuvant treatment. In the neoadjuvant setting, letrozole has been especially effective compared with tamoxifen in downstaging primary tumors in postmenopausal women, permitting significantly more breast-conserving surgery.

  2. Synthesis of Novel Chalcones as Acetylcholinesterase Inhibitors

    Directory of Open Access Journals (Sweden)

    Thanh-Dao Tran


    Full Text Available A new series of benzylaminochalcone derivatives with different substituents on ring B were synthesized and evaluated as inhibitors of acetylcholinesterase. The study is aimed at identification of novel benzylaminochalcones capable of blocking acetylcholinesterase activity for further development of an approach to Alzheimer’s disease treatment. These compounds were produced in moderate to good yields via Claisen-Schmidt condensation and subjected to an in vitro acetylcholinesterase inhibition assay, using Ellman’s method. The in silico docking procedure was also employed to identify molecular interactions between the chalcone compounds and the enzyme. Compounds with ring B bearing pyridin-4-yl, 4-nitrophenyl, 4-chlorophenyl and 3,4-dimethoxyphenyl moieties were discovered to exhibit significant inhibitory activities against acetylcholinesterase, with IC50 values ranging from 23 to 39 µM. The molecular modeling studies are consistent with the hypothesis that benzylaminochalcones could exert their effects as dual-binding-site acetylcholinesterase inhibitors, which might simultaneously enhance cholinergic neurotransmission and inhibit β-amyloid aggregation through binding to both catalytic and peripheral sites of the enzyme. These derivatives could be further developed to provide novel leads for the discovery of new anti-Alzheimer drugs in the future.

  3. Polyphenol Compound as a Transcription Factor Inhibitor

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    Seyeon Park


    Full Text Available A target-based approach has been used to develop novel drugs in many therapeutic fields. In the final stage of intracellular signaling, transcription factor–DNA interactions are central to most biological processes and therefore represent a large and important class of targets for human therapeutics. Thus, we focused on the idea that the disruption of protein dimers and cognate DNA complexes could impair the transcriptional activation and cell transformation regulated by these proteins. Historically, natural products have been regarded as providing the primary leading compounds capable of modulating protein–protein or protein-DNA interactions. Although their mechanism of action is not fully defined, polyphenols including flavonoids were found to act mostly as site-directed small molecule inhibitors on signaling. There are many reports in the literature of screening initiatives suggesting improved drugs that can modulate the transcription factor interactions responsible for disease. In this review, we focus on polyphenol compound inhibitors against dimeric forms of transcription factor components of intracellular signaling pathways (for instance, c-jun/c-fos (Activator Protein-1; AP-1, c-myc/max, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and β-catenin/T cell factor (Tcf.

  4. Replication and Inhibitors of Enteroviruses and Parechoviruses

    Directory of Open Access Journals (Sweden)

    Lonneke van der Linden


    Full Text Available The Enterovirus (EV and Parechovirus genera of the picornavirus family include many important human pathogens, including poliovirus, rhinovirus, EV-A71, EV-D68, and human parechoviruses (HPeV. They cause a wide variety of diseases, ranging from a simple common cold to life-threatening diseases such as encephalitis and myocarditis. At the moment, no antiviral therapy is available against these viruses and it is not feasible to develop vaccines against all EVs and HPeVs due to the great number of serotypes. Therefore, a lot of effort is being invested in the development of antiviral drugs. Both viral proteins and host proteins essential for virus replication can be used as targets for virus inhibitors. As such, a good understanding of the complex process of virus replication is pivotal in the design of antiviral strategies goes hand in hand with a good understanding of the complex process of virus replication. In this review, we will give an overview of the current state of knowledge of EV and HPeV replication and how this can be inhibited by small-molecule inhibitors.

  5. Lonafarnib is a potential inhibitor for neovascularization.

    Directory of Open Access Journals (Sweden)

    Linlin Sun

    Full Text Available Atherosclerosis is a common cardiovascular disease that involves the build-up of plaque on the inner walls of the arteries. Intraplaque neovacularization has been shown to be essential in the pathogenesis of atherosclerosis. Previous studies showed that small-molecule compounds targeting farnesyl transferase have the ability to prevent atherosclerosis in apolipoprotein E-deficient mice, but the underlying mechanism remains to be elucidated. In this study, we found that lonafarnib, a specific inhibitor of farnesyl transferase, elicits inhibitory effect on vascular endothelial capillary assembly in vitro in a dose-dependent manner. In addition, we showed that lonafarnib treatment led to a dose-dependent decrease in scratch wound closure in vitro, whereas it had little effect on endothelial cell proliferation. These data indicate that lonafarnib inhibits neovascularization via directly targeting endothelial cells and disturbing their motility. Moreover, we demonstrated that pharmacological inhibition of farnesyl transferase by lonafarnib significantly impaired centrosome reorientation toward the leading edge of endothelial cells. Mechanistically, we found that the catalytic β subunit of farnesyl transferase associated with a cytoskeletal protein important for the establishment and maintenance of cell polarity. Additionally, we showed that lonafarnib remarkably inhibited the expression of the cytoskeletal protein and interrupted its interaction with farnesyl transferase. Our findings thus offer novel mechanistic insight into the protective effect of farnesyl transferase inhibitors on atherosclerosis and provide encouraging evidence for the potential use of this group of agents in inhibiting plaque neovascularization.

  6. Phytochemicals as Inhibitors of Candida Biofilm. (United States)

    Raut, Jayant Shankar; Karuppayil, Sankunny Mohan


    Candida biofilm and associated infections is a serious threat to the large population of immunocompromised patients. Biofilm growth on prosthetic devices or host tissue shows reduced sensitivity to antifungal agents and persists as a reservoir of infective cells. Options for successful treatment of biofilm associated Candida infections are restricted because most of the available antifungal drugs fail to eradicate biofilms. Various plant actives are known to possess interesting antifungal properties. To explore and review the potential of phytochemicals as a novel strategy against Candida biofilms is the intent of present article. Thorough literature search is performed to identify Candida biofilm inhibitors of plant origin. An account of efficacy of selected phytochemicals is presented taking into consideration their biofilm inhibitory concentrations. This review discusses biofilm formation by Candida species, their involvement in human infections, and associated drug resistance. It gives insight into the biofilm inhibitory potential of various phytochemicals. Based on the available reports including the work done in our laboratory, several plant extracts, essential oils and phytomolecules have been identified as excellent inhibitors of biofilms of C. albicans and non-albicans Candida species (NACS). Selected phytochemicals which exhibit activities at low concentrations without displaying toxicity to host are potential therapeutic agents against biofilm associated Candida infections. In vivo testing in animal models and clinical trials in humans are required to be taken up seriously to propose few of the phytochemicals as candidate drug molecules.

  7. PD-1 Checkpoint Inhibitor Associated Autoimmune Encephalitis

    Directory of Open Access Journals (Sweden)

    Stephanie Schneider


    Full Text Available Objective: To report first-hand narrative experience of autoimmune encephalitis and to briefly review currently available evidence of autoimmune encephalitis in cancer patients treated with immune checkpoint inhibitors. Setting: A case study is presented on the management of a patient who developed autoimmune encephalitis during nivolumab monotherapy occurring after 28 weeks on anti-PD-1 monotherapy (nivolumab 3 mg/kg every 2 weeks for non-small cell lung cancer. Results: No substantial improvement was observed by antiepileptic treatment. After administration of 80 mg methylprednisolone, neurologic symptoms disappeared within 24 h and the patient fully recovered. Conclusions: Immune checkpoint inhibitor treatment can lead to autoimmune encephalitis. Clinical trial data indicate a frequency of autoimmune encephalitis of ≥0.1 to <1% with a higher probability during combined or sequential anti-CTLA-4/anti-PD-1 therapy than during anti-PD-1 or anti-PD-L1 monotherapy. Further collection of evidence and translational research is warranted.

  8. RNA aptamer inhibitors of a restriction endonuclease. (United States)

    Mondragón, Estefanía; Maher, L James


    Restriction endonucleases (REases) recognize and cleave short palindromic DNA sequences, protecting bacterial cells against bacteriophage infection by attacking foreign DNA. We are interested in the potential of folded RNA to mimic DNA, a concept that might be applied to inhibition of DNA-binding proteins. As a model system, we sought RNA aptamers against the REases BamHI, PacI and KpnI using systematic evolution of ligands by exponential enrichment (SELEX). After 20 rounds of selection under different stringent conditions, we identified the 10 most enriched RNA aptamers for each REase. Aptamers were screened for binding and specificity, and assayed for REase inhibition. We obtained eight high-affinity (Kd ∼12-30 nM) selective competitive inhibitors (IC50 ∼20-150 nM) for KpnI. Predicted RNA secondary structures were confirmed by in-line attack assay and a 38-nt derivative of the best anti-KpnI aptamer was sufficient for inhibition. These competitive inhibitors presumably act as KpnI binding site analogs, but lack the primary consensus KpnI cleavage sequence and are not cleaved by KpnI, making their potential mode of DNA mimicry fascinating. Anti-REase RNA aptamers could have value in studies of REase mechanism and may give clues to a code for designing RNAs that competitively inhibit DNA binding proteins including transcription factors. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

  9. Structure-based inhibitors of tau aggregation (United States)

    Seidler, P. M.; Boyer, D. R.; Rodriguez, J. A.; Sawaya, M. R.; Cascio, D.; Murray, K.; Gonen, T.; Eisenberg, D. S.


    Aggregated tau protein is associated with over 20 neurological disorders, which include Alzheimer's disease. Previous work has shown that tau's sequence segments VQIINK and VQIVYK drive its aggregation, but inhibitors based on the structure of the VQIVYK segment only partially inhibit full-length tau aggregation and are ineffective at inhibiting seeding by full-length fibrils. Here we show that the VQIINK segment is the more powerful driver of tau aggregation. Two structures of this segment determined by the cryo-electron microscopy method micro-electron diffraction explain its dominant influence on tau aggregation. Of practical significance, the structures lead to the design of inhibitors that not only inhibit tau aggregation but also inhibit the ability of exogenous full-length tau fibrils to seed intracellular tau in HEK293 biosensor cells into amyloid. We also raise the possibility that the two VQIINK structures represent amyloid polymorphs of tau that may account for a subset of prion-like strains of tau.

  10. Flavonoids as Inhibitors of Human Butyrylcholinesterase Variants

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    Maja Katalinić


    Full Text Available The inhibition of butyrylcholinesterase (BChE, EC appears to be of interest in treating diseases with symptoms of reduced neurotransmitter levels, such as Alzheimer’s disease. However, BCHE gene polymorphism should not be neglected in research since it could have an effect on the expected outcome. Several well-known cholinergic drugs (e.g. galantamine, huperzine and rivastigmine originating from plants, or synthesised as derivatives of plant compounds, have shown that herbs could serve as a source of novel target-directed compounds. We focused our research on flavonoids, biologically active polyphenolic compounds found in many plants and plant-derived products, as BChE inhibitors. All of the tested flavonoids: galangin, quercetin, fisetin and luteolin reversibly inhibited usual, atypical, and fluoride-resistant variants of human BChE. The inhibition potency increased in the following order, identically for all three BChE variants: luteolininhibitor dissociation constants (Ki ranged from 10 to 170 mmol/L. We showed that no significant change in the inhibition potency of selected flavonoids exists in view of BChE polymorphism. Our results suggested that flavonoids could assist the further development of new BChE-targeted drugs for treating symptoms of neurodegenerative diseases and dementia.

  11. Application of response surface methodology method in designing corrosion inhibitor (United States)

    Asmara, Y. P.; Athirah; Siregar, J. P.; Kurniawan, T.; Bachtiar, D.


    In oil and gas pipelines and offshore structure, inhibitors have been considered to be the first choice to reduce corrosion rate. There are many corrosion inhibitor compositions available in the market. To produce the best corrosion inhibitor requires many experimental data which is not efficient. These experiments used response surface methodology (RSM) to select corrosion inhibitor compositions. The experiments investigated effects of corrosion inhibition on corrosion rate of low carbon steel in 3% NaCl solution with different concentrations of selected main inhibitor compositions which are ethyl acetate (EA), ethylene glycol (EG) and sodium benzoate (SB). Corrosion rate were calculated using linear polarization resistance (LPR). All of the experiments were set in natural conditions at pH 7. MINITAB® version 15 was used for data analysis. It is shown that a quadratic model is a representative model can predict best corrosion inhibitor composition comprehensibly.

  12. Use of Silica Tubes as Nanocontainers for Corrosion Inhibitor Storage

    Directory of Open Access Journals (Sweden)

    Cesia Ávila-Gonzalez


    Full Text Available A new alkyd paint anticorrosion smart coating was developed by using silica nanoparticles as corrosion inhibitor nanocontainers. Silica particles were mixed with the paint at different concentrations to study their performance and ensure their free transportation to the damaged metal. The filling up of silica particles was done preparing three solutions: distilled water, acetone, and a mixture of both, with Fe(NO33 and silica particles immersed in each of the solutions to adsorb the inhibitor. Acetone solution was the best alternative determined by weight gain analysis made with the inhibitor adsorbed in silica nanocontainers. Steel samples were painted with inhibitor silica nanocontainer coatings and immersed in an aqueous solution of 3% sodium chloride. Polarization curves and electrochemical noise techniques were used to evaluate the corrosion inhibitor system behavior. Good performance was obtained in comparison with samples without inhibitor nanocontainer coating.

  13. GSK-3 inhibitors: preclinical and clinical focus on CNS

    Directory of Open Access Journals (Sweden)

    Hagit eEldar-Finkelman


    Full Text Available Inhibiting glycogen synthase kinase-3 (GSK-3 activity via pharmacological intervention has become an important target for treating neurodegenerative and psychiatric disorders. The reported GSK-3 inhibitors are of diverse chemotypes and mechanisms of action that include compounds isolated from natural sources, cations, synthetic small-molecule ATP-competitive inhibitors, non-ATP-competitive inhibitors, and substrate-competitive inhibitors. Here we describe the variety of GSK-3 inhibitors with a specific emphasis on their biological activities in neurons and neurological disorders. We further highlight our current progress in the development of non-ATP-competitive inhibitors of GSK-3.The available data raises the hope that one or more of these drug design approaches will prove successful at stabilizing or even reversing the aberrant neuropathology and cognitive deficits of certain CNS disorders.

  14. Internet Selling Expansion Inhibitors: A Mixed Method Approach

    Directory of Open Access Journals (Sweden)

    Shahriar Azizi


    Full Text Available This research based on providing five questions has tried to identify and prioritize the main and sub inhibitors of internet selling boosting in Iran. A mixed method research (QUAN has been used in this research. In the qualitative phase, individual in-depth interviews have been done with seven e-shop managers. In this phase, 45 detailed inhibitors have been detected. These 45 inhibitors have been categorized in nine sub categories and four main categories. In the quantitative phase a 51-items questionnaires has been designed including six demographical and 45 specialized questions. Findings of the quantitative phase reveal that the main obstacles include legal, cultural, infrastructural and managerial inhibitors. In addition, sub category inhibitors include legal, governmental, telecommunication, society, human resource, transportation, financial and customer related.     Keywords: e-selling, Iran, Inhibitors, Mixed method.

  15. The Place of protease inhibitors in antiretroviral treatment

    Directory of Open Access Journals (Sweden)

    S.B. Tenore

    Full Text Available With the introduction of highly active antiretroviral therapy, a number of drugs have been developed. The best choice concerning which antiretroviral analogs to start is always under discussion, especially in the choice between non-nucleoside reverse transcriptase inhibitors-based therapies and ritonavir-boosted protease inhibitors. Both are proven to control viral replication and lead to immunological gain. The choice between a non-nucleoside analog reverse transcriptase inhibitor and a protease inhibitor as a third antiretroviral drug in the therapy should consider factors related to the individual, as well as the inclusion of the best therapy in the patient's daily activities and potential adherence. The protease inhibitor-based therapies showed similar efficacy among the various inhibitors with characteristics concerning the adverse events from each medicine. For the treatment of protease-resistant patients, darunavir and tipranavir showed good efficacy with higher genetic barrier to resistance.

  16. Aromatase inhibitors in men: effects and therapeutic options

    Directory of Open Access Journals (Sweden)

    de Jong Frank H


    Full Text Available Abstract Aromatase inhibitors effectively delay epiphysial maturation in boys and improve testosterone levels in adult men Therefore, aromatase inhibitors may be used to increase adult height in boys with gonadotropin-independent precocious puberty, idiopathic short stature and constitutional delay of puberty. Long-term efficacy and safety of the use of aromatase inhibitors has not yet been established in males, however, and their routine use is therefore not yet recommended.

  17. Towards a unified model of RAF inhibitor resistance. (United States)

    Solit, David B; Rosen, Neal


    ATP-competitive RAF inhibitors elicit profound but often temporary antitumor responses in patients with BRAF-mutant melanoma. Analysis of tumor samples collected at the time of disease progression indicates that alterations within the extracellular signal-regulated kinase (ERK) pathway that result in reactivation of ERK signaling are present in most patients. Mutations in the phosphoinositide 3-kinase/AKT pathway that enhance the adaptive response to RAF inhibitors also contribute to RAF inhibitor resistance in a subset of patients.

  18. Identifying Determinants of PARP Inhibitor Sensitivity in Ovarian Cancer (United States)


    Maryland 21702-5012 Approved for Public Release; Distribution Unlimited Identifying Determinants of PARP Inhibitor Sensitivity in Ovarian Cancer October...NOTES 14. ABSTRACT 15. SUBJECT TERMS Ovarian cancer , BRCA1, RAD51, PARP inhibitors, platinum, biomarkers, drug resistance 16. SECURITY CLASSIFICATION...Identifying Determinants of PARP Inhibitor Sensitivity in Ovarian Cancer Form Approved OMB No. 0704-0188 Public reporting burden for this collection of

  19. Natural compounds as corrosion inhibitors for highly cycled systems

    Energy Technology Data Exchange (ETDEWEB)

    Quraishi, M.A.; Farooqi, I.H.; Saini, P.A. [Corrosion Research Lab., Aligarh (India)


    Strict environmental legislations have led to the development of green inhibitors in recent years. In continuation of the authors` research work on development of green inhibitors, they have investigated the aqueous extracts of three plants namely: Azadirachta indica, Punica Granatum and Momordica charantia as corrosion inhibitors for mild steel in 3% NaCl using weight loss and electrochemical methods. All the investigated compounds exhibited excellent corrosion inhibition properties comparable to that of HEDP. Azadirachta showed better scale inhibition effect than HEDP.

  20. Diversity of marine bacteria producing beta-glucosidase inhibitors. (United States)

    Pandey, Sony; Sree, Ayinampudi; Dash, Soumya Suchismita; Sethi, Dipti Priya; Chowdhury, Lipsa


    Beta-glucosidase inhibitors are being extensively studied for use as anti-diabetics, anti-obesity and anti-tumour compounds. So far, these compounds have been reported in large numbers from plants, mushrooms, algae and fungi. There are very few reports of such inhibitors from bacteria in the open literature, particularly marine bacteria; although the best known inhibitor deoxynojirimycin was isolated from bacilli and actinomycete. Through this study, we tried to discover the diversity of microbial associates of marine sponge and sediment producing β-glucosidase inhibitors. We found 41 (22.7%) out of 181 bacteria, produced such inhibitors. The inhibitors are abundant in bacterial associates of marine sponge Aka coralliphaga. When these bacteria were phylogenetically analyzed, it was found that marine bacteria producing glucosidase inhibitors belong to the phylum Firmicutes (23), Actinobacteria (9), Proteobacteria (7) and Bacteroidetes (1). A significant number of marine bacteria belonging to a wide range of bacterial taxa were found to produce β-glucosidase inhibitors. These compounds are abundantly present in bacteria of the phylum Firmicutes followed by the phylum Actinobacteria. The results nurture a hope of finding new compounds, which can inhibit glucosidases, in the bacterial domain of marine organisms. Thus, marine microbial cells can be utilized as producers of pharmacologically essential enzyme inhibitors.

  1. Discovery of potent, selective sulfonylfuran urea endothelial lipase inhibitors. (United States)

    Goodman, Krista B; Bury, Michael J; Cheung, Mui; Cichy-Knight, Maria A; Dowdell, Sarah E; Dunn, Allison K; Lee, Dennis; Lieby, Jeffrey A; Moore, Michael L; Scherzer, Daryl A; Sha, Deyou; Suarez, Dominic P; Murphy, Dennis J; Harpel, Mark R; Manas, Eric S; McNulty, Dean E; Annan, Roland S; Matico, Rosalie E; Schwartz, Benjamin K; Trill, John J; Sweitzer, Thomas D; Wang, Da-Yuan; Keller, Paul M; Krawiec, John A; Jaye, Michael C


    Endothelial lipase (EL) activity has been implicated in HDL catabolism, vascular inflammation, and atherogenesis, and inhibitors are therefore expected to be useful for the treatment of cardiovascular disease. Sulfonylfuran urea 1 was identified in a high-throughput screening campaign as a potent and non-selective EL inhibitor. A lead optimization effort was undertaken to improve potency and selectivity, and modifications leading to improved LPL selectivity were identified. Radiolabeling studies were undertaken to establish the mechanism of action for these inhibitors, which were ultimately demonstrated to be irreversible inhibitors.

  2. Predicting DPP-IV inhibitors with machine learning approaches (United States)

    Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun


    Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

  3. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

    Directory of Open Access Journals (Sweden)

    Shohei Sakuda


    Full Text Available Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control.

  4. Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production (United States)

    Sakuda, Shohei; Prabowo, Diyan Febri; Takagi, Keiko; Shiomi, Kazuro; Mori, Mihoko; Ōmura, Satoshi; Nagasawa, Hiromichi


    Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A) inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III) and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control. PMID:24674936

  5. High throughput in vivo protease inhibitor selection platform

    DEFF Research Database (Denmark)


    The invention relates to a recombinant microbial cell comprising a selection platform for screening for a protease inhibitor, wherein the platform comprises transgenes encoding a protease having selective peptide bond cleavage activity at a recognition site amino acid sequence; and transgenes...... encoding polypeptides conferring resistance to microbial growth inhibitors; wherein the polypeptides comprise the recognition site amino acid sequence cleavable by the protease. Protease inhibitors are detected by their ability to inhibit protease specific cleavage and inactivation of the polypeptides...... platform for screening for a protease inhibitor....

  6. Solderability preservation through the use of organic inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, N.R.; Hosking, F.M.


    Organic inhibitors can be used to prevent corrosion of metals and have application in the electronics industry as solderability preservatives. We have developed a model to describe the action of two inhibitors (benzotriazole and imidazole) during the environmental aging and soldering process. The inhibitors bond with the metal surface and form a barrier that prevents or retards oxidation. At soldering temperatures, the metal-organic complex breaks down leaving an oxide-free metal surface that allows excellent wetting by molten solder. The presence of the inhibitor retards the wetting rate relative to clean copper, but provides a vast improvement relative to oxidized copper.

  7. Behaviour of tetramine inhibitors during pickling of hot rolled steels

    Energy Technology Data Exchange (ETDEWEB)

    Cornu, Marie-José, E-mail: [ArcelorMittal Maizières Research, Voie Romaine, 57280 Maizières-lès-Metz (France); Koltsov, Alexey, E-mail: [ArcelorMittal Maizières Research, Voie Romaine, 57280 Maizières-lès-Metz (France); Nicolas, Sabrina, E-mail: [ArcelorMittal Maizières Research, Voie Romaine, 57280 Maizières-lès-Metz (France); Laboratoire de Chimie Physique et Microbiologie pour l’Environnement (LCPME) – UMR 7564 CNRS – Université de Lorraine, 405 rue de Vandoeuvre, 54602 Villers-lès-Nancy (France); Colom, Lydia, E-mail: [ArcelorMittal Maizières Research, Voie Romaine, 57280 Maizières-lès-Metz (France); Dossot, Manuel, E-mail: [Laboratoire de Chimie Physique et Microbiologie pour l’Environnement (LCPME) – UMR 7564 CNRS – Université de Lorraine, 405 rue de Vandoeuvre, 54602 Villers-lès-Nancy (France)


    To avoid the dissolution of steel in industrial pickling process, tetramine inhibitors are added to the pickling bath. This study is devoted to the understanding of the action mechanism of these inhibitors in hydrochloric and sulphuric baths on non-alloyed and alloyed steels. Pickling experiments and characterization with XPS, Raman and infrared spectroscopies have shown that inhibitors work only in acid media and leached out from the steel surfaces during the rinsing operation just after pickling. The effectiveness of inhibitors depends on the acid media and the temperature. Experimental data are consistent with a surface mechanism, i.e., the so-called “outer-sphere” adsorption.

  8. The effects of residual platelets in plasma on plasminogen activator inhibitor-1 and plasminogen activator inhibitor-1-related assays.

    Directory of Open Access Journals (Sweden)

    Marlien Pieters

    Full Text Available Due to controversial evidence in the literature pertaining to the activity of plasminogen activator inhibitor-1 in platelets, we examined the effects of residual platelets present in plasma (a potential pre-analytical variable on various plasminogen activator inhibitor-1 and plasminogen activator inhibitor-1-related assays. Blood samples were collected from 151 individuals and centrifuged at 352 and 1500 g to obtain plasma with varying numbers of platelet. In a follow-up study, blood samples were collected from an additional 23 individuals, from whom platelet-poor (2000 g, platelet-containing (352 g and platelet-rich plasma (200 g were prepared and analysed as fresh-frozen and after five defrost-refreeze cycles (to determine the contribution of in vitro platelet degradation. Plasminogen activator inhibitor-1 activity, plasminogen activator inhibitor-1 antigen, tissue plasminogen activator/plasminogen activator inhibitor-1 complex, plasma clot lysis time, β-thromboglobulin and plasma platelet count were analysed. Platelet α-granule release (plasma β-thromboglobulin showed a significant association with plasminogen activator inhibitor-1 antigen levels but weak associations with plasminogen activator inhibitor-1 activity and a functional marker of fibrinolysis, clot lysis time. Upon dividing the study population into quartiles based on β-thromboglobulin levels, plasminogen activator inhibitor-1 antigen increased significantly across the quartiles while plasminogen activator inhibitor-1 activity and clot lysis time tended to increase in the 4th quartile only. In the follow-up study, plasma plasminogen activator inhibitor-1 antigen was also significantly influenced by platelet count in a concentration-dependent manner. Plasma plasminogen activator inhibitor-1 antigen levels increased further after complete platelet degradation. Residual platelets in plasma significantly influence plasma plasminogen activator inhibitor-1 antigen levels mainly

  9. Profiling of differentially expressed genes in haemophilia A with inhibitor. (United States)

    Hwang, S H; Lim, J A; Kim, M J; Kim, H C; Lee, H W; Yoo, K Y; You, C W; Lee, K S; Kim, H S


    Inhibitor development is the most significant complication in the therapy of haemophilia A (HA) patients. In spite of many studies, not much is known regarding the mechanism underlying inhibitor development. To understand the mechanism, we analysed profiles of differentially expressed genes (DEGs) between inhibitor and non-inhibitor HA via a microarray technique. Twenty unrelated Korean HAs were studied: 11 were non-inhibitor and nine were HA with inhibitor (≥5 BU mL(-1)). Microarray analysis was conducted using a Human Ref-8 expression Beadchip system (Illumina) and the data were analysed using Beadstudio software. We identified 545 DEGs in inhibitor HA as compared with the non-inhibitor patients; 384 genes were up-regulated and 161 genes were down-regulated. Among them, 75 genes whose expressions were altered by at least two-fold (>+2 or genes differed significantly in the two groups. For validation of the DEGs, semi-quantitative RT-PCR (semi-qRT-PCR) was conducted with the six selected DEGs. The results corresponded to the microarray data, with the exception of one gene. We also examined the expression of the genes associated with the antigen presentation process via real-time PCR. The average levels of IL10, CTLA4 and TNFα slightly reduced, whereas that of IFNγ increased in the inhibitor HA group. We are currently unable to explain whether this phenomenon is a function of the inhibitor-inducing factor or is an epiphenomenon of antibody production. Nevertheless, our results provide a possible explanation for inhibitor development. © 2011 Blackwell Publishing Ltd.

  10. Insect response to plant defensive protease inhibitors. (United States)

    Zhu-Salzman, Keyan; Zeng, Rensen


    Plant protease inhibitors (PIs) are natural plant defense proteins that inhibit proteases of invading insect herbivores. However, their anti-insect efficacy is determined not only by their potency toward a vulnerable insect system but also by the response of the insect to such a challenge. Through the long history of coevolution with their host plants, insects have developed sophisticated mechanisms to circumvent antinutritional effects of dietary challenges. Their response takes the form of changes in gene expression and the protein repertoire in cells lining the alimentary tract, the first line of defense. Research in insect digestive proteases has revealed the crucial roles they play in insect adaptation to plant PIs and has brought about a new appreciation of how phytophagous insects employ this group of molecules in both protein digestion and counterdefense. This review provides researchers in related fields an up-to-date summary of recent advances.

  11. Evolution of resistance to quorum sensing inhibitors (United States)

    Kalia, Vipin C.; Wood, Thomas K.; Kumar, Prasun


    The major cause of mortality and morbidity in human beings is bacterial infection. Bacteria have developed resistance to most of the antibiotics primarily due to large scale and “indiscriminate” usage. The need is to develop novel mechanisms to treat bacterial infections. The expression of pathogenicity during bacterial infections is mediated by a cell density dependent phenomenon known as quorum sensing (QS). A wide array of QS systems (QSS) is operative in expressing the virulent behavior of bacterial pathogens. Each QSS may be mediated largely by a few major signals along with others produced in minuscule quantities. Efforts to target signal molecules and their receptors have proved effective in alleviating the virulent behavior of such pathogenic bacteria. These QS inhibitors (QSIs) have been reported to be effective in influencing the pathogenicity without affecting bacterial growth. However, evidence is accumulating that bacteria may develop resistance to QSIs. The big question is whether QSIs will meet the same fate as antibiotics? PMID:24194099

  12. Developing BACE-1 inhibitors for FXS

    Directory of Open Access Journals (Sweden)

    Cara J Westmark


    Full Text Available Fragile X syndrome (FXS is a debilitating genetic disorder with no cure and few therapeutic options. Excessive signaling through metabotropic glutamate receptor 5 (mGluR5 in FXS leads to increased translation of numerous synaptic proteins and exaggerated long-term depression (LTD. Two of the overexpressed proteins are amyloid-beta protein precursor (APP and its metabolite amyloid-beta (Aβ, which have been well-studied in Alzheimer’s disease (AD. Here we discus the possibility that pharmaceuticals under study for the modulation of these proteins in AD might be viable therapeutic strategies for FXS. Specifically, a recently identified acetyltransferase (ATase inhibitor that reduces the levels and activity of β-site APP cleaving enzyme (BACE-1 has strong potential to attenuate BACE-1 activity and maintain homeostatic levels APP catabolites in FXS.

  13. Strategies for discontinuation of proton pump inhibitors

    DEFF Research Database (Denmark)

    Haastrup, Peter; Paulsen, Maja S; Begtrup, Luise M


    and ongoing studies. A total of 371 abstracts were scrutinized to determine relevancy. RESULTS: The thorough search resulted in six clinical studies on strategies for discontinuation of PPIs. All discontinuation regimens used in the studies differed, and several interventions have been tested in order...... to decrease use of PPIs. Discontinuations were reported across all studies ranging from 14% to 64% without deteriorating symptom control. Tapering seems to be a more effective discontinuation strategy than abrupt discontinuation. CONCLUSION: Discontinuation of PPIs is feasible in a clinical setting......PURPOSE: Proton pump inhibitors (PPIs) are considered to be overprescribed. Consensus on how to attempt discontinuation is, however, lacking. We therefore conducted a systematic review of clinical studies on discontinuation of PPIs. METHODS: Systematic review based on clinical studies investigating...

  14. New Acetylcholinesterase Inhibitors for Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Mona Mehta


    Full Text Available Acetylcholinesterase (AChE remains a highly viable target for the symptomatic improvement in Alzheimer's disease (AD because cholinergic deficit is a consistent and early finding in AD. The treatment approach of inhibiting peripheral AchE for myasthenia gravis had effectively proven that AchE inhibition was a reachable therapeutic target. Subsequently tacrine, donepezil, rivastigmine, and galantamine were developed and approved for the symptomatic treatment of AD. Since then, multiple cholinesterase inhibitors (ChEI continue to be developed. These include newer ChEIs, naturally derived ChEIs, hybrids, and synthetic analogues. In this paper, we summarize the different types of ChEIs in development and their respective mechanisms of actions. This pharmacological approach continues to be active with many promising compounds.

  15. The Glycosylation of Plasminogen Activator Inhibitor-1

    DEFF Research Database (Denmark)

    Skottrup, Peter; Pedersen, Katrine Egelund; Christensen, Anni


    spectrometry and monosaccharide composition analysis and compared to that of natural and recombinant PAI-1 from other sources. These results contribute to a structural basis for previous observations of a different functional importance of the N-linked glycosylation at each of the 2 sequences.......Plasminogen activator inhibitor type-1 (PAI-1) has three potential sites for N-linked glycosylation, including Asn209Tyr210Thr211, Asn265Met266Thr267, and Asn329Glu330Ser331. Using a HEK293 expression system, we have made mutants with Asp or Gln substitutions of the Asn residue in each...... of these sequences. Analyses of these mutants for the content of N-acetyl glucosamine showed that Asn209 and Asn265, but not Asn329, are glycosylated, in agreement with previous suggestions made on the basis of X-ray crystal structure analysis of PAI-1 expressed in CHO cells (Xue et al. (1998) Structure 6, 627...

  16. The Glycosylation of Plasminogen Activator Inhibitor-1

    DEFF Research Database (Denmark)

    Skottrup, Peter; Pedersen, Katrine Egelund; Christensen, Anni

    spectrometry and monosaccharide composition analysis and compared to that of natural and recombinant PAI-1 from other sources. These results contribute to a structural basis for previous observations of a different functional importance of the N-linked glycosylation at each of the 2 sequences.......Plasminogen activator inhibitor type-1 (PAI-1) has three potential sites for N-linked glycosylation, including Asn209Tyr210Thr211, Asn265Met266Thr267, and Asn329Glu330Ser331. Using a HEK293 expression system, we have made mutants with Asp or Gln substitutions of the Asn residue in each...... of these sequences. Analyses of these mutants for the content of N-acetyl glucosamine showed that Asn209 and Asn265, but not Asn329, are glycosylated, in agreement with previous suggestions made on the basis of X-ray crystal structure analysis of PAI-1 expressed in CHO cells (Xue et al. (1998) Structure 6, 627...

  17. Aspirin and Other COX-1 inhibitors. (United States)

    Patrono, Carlo; Rocca, Bianca


    Currently available antiplatelet drugs interfere with the process of platelet activation and aggregation by selectively blocking key enzymes involved in the synthesis of platelet agonists, or membrane receptors mediating activation signals. Pharmacological interference with critical molecular pathways of platelet activation and aggregation may reduce the risk of atherothrombotic complications through mechanisms that are also responsible for an increased risk of bleeding. Acetylsalicylic acid (aspirin) represents a prototypic antiplatelet agent. The aim of this chapter is to integrate our current understanding of the molecular mechanism of action of aspirin with the results of clinical trials and epidemiological studies assessing its efficacy and safety. Moreover, the antiplatelet properties of reversible inhibitors of the same drug target will also be reviewed.

  18. Randomized controlled trials of COX-2 inhibitors

    DEFF Research Database (Denmark)

    Stefansdottir, Gudrun; De Bruin, Marie L; Knol, Mirjam J


    BACKGROUND: Naproxen, ibuprofen and diclofenac are frequently used as comparators in randomized controlled trials (RCTs) on the safety and efficacy of cyclooxygenase (COX)-2 inhibitors. Different comparator doses may influence the results of RCTs. It has been hypothesized that RCTs of COX-2...... 1995 and 2009 in which celecoxib or rofecoxib were compared with naproxen, ibuprofen or diclofenac. All articles labelled as RCTs mentioning rofecoxib or celecoxib and one or more of the comparator drugs in the title and/or abstract were included. We extracted information on doses of both non...... dose trends in the case of rofecoxib. CONCLUSIONS: Although the dose trends over time differed for RCTs comparing rofecoxib and celecoxib with diclofenac, ibuprofen or naproxen, the results of our study do not support the hypothesis that dose trends influenced the decision to continue marketing...

  19. Casein kinase 2 inhibition attenuates androgen receptor function and cell proliferation in prostate cancer cells. (United States)

    Yao, Kai; Youn, Hyewon; Gao, Xiaoyan; Huang, Bijun; Zhou, Fangjian; Li, Benyi; Han, Hui


    Casein kinase 2 (CK2) is constitutively active with dual specificity and exists as a hetero-tetrameric complex of α, α', and β subunits. Its aberrant expression and elevated activity have been linked to many human cancers, including prostate cancer. As an effort to develop new chemotherapy for prostate cancers, in this study, we tested the effects of tetra-bromo-cinnamic acid (TBCA), a newly synthetic CK2-selective CK2 inhibitor, on androgen receptor (AR) transactivation, cell proliferation, and viability in multiple prostate cancer cell lines. We utilized a comprehensive approach of a newly synthetic CK2-selective inhibitor TBCA, plus gene-specific siRNAs in multiple cell-based assays to further understand the role of CK2 in AR signaling. Alamar-blue-based cell growth assay, flow cytometry for cell cycle distribution, Luciferase report gene assay for AR transactivation, and immuno-fluorescent approach for AR nuclear localization as well as quantitative PCR assay for AR-mediated gene expression were utilized. The significance of the differences between treatment and control was analyzed using the SPSS software (SPSS, Chicago, IL). Our data revealed that TBCA reduced cell proliferation and caused G2/M cell cycle arrest in a dose-dependent manner. Further analysis demonstrated that TBCA blocked AR nuclear translocation and gene expression. To confirm the target specificity, we used gene-specific siRNAs for both CK2α and CK2α' subunits, and the results suggested that both CK2 catalytic subunits are involved in androgen-stimulated AR nuclear translocation and AR-mediated gene expression in prostate cancer cells. CK2 subunits α and α' are likely involved in AR signaling, and TBCA might be useful in the management of prostate cancers as a chemo-preventive agent in the future. Copyright © 2012 Wiley Periodicals, Inc.

  20. Use of proteasome inhibitors in anticancer therapy

    Directory of Open Access Journals (Sweden)

    Sara M. Schmitt


    Full Text Available The importance of the ubiquitin-proteasome pathway to cellular function has brought it to the forefront in the search for new anticancer therapies. The ubiquitin-proteasome pathway has proven promising in targeting various human cancers. The approval of the proteasome inhibitor bortezomib for clinical treatment of relapsed/refractory multiple myeloma and mantle cell lymphoma has validated the ubiquitin-proteasome as a rational target. Bortezomib has shown positive results in clinical use but some toxicity and side effects, as well as resistance, have been observed, indicating that further development of novel, less toxic drugs is necessary. Because less toxic drugs are necessary and drug development can be expensive and time-consuming, using existing drugs that can target the ubiquitin-proteasome pathway in new applications, such as cancer therapy, may be effective in expediting the regulatory process and bringing new drugs to the clinic. Toward this goal, previously approved drugs, such as disulfiram, as well as natural compounds found in common foods, such as green tea polyphenol (--EGCG and the flavonoid apigenin, have been investigated for their possible proteasome inhibitory and cell death inducing abilities. These compounds proved quite promising in preclinical studies and have now moved into clinical trials, with preliminary results that are encouraging. In addition to targeting the catalytic activity of the proteasome pathway, upstream regulators, such as the 19S regulatory cap, as well as E1, E2, and E3, are now being investigated as potential drug targets. This review outlines the development of novel proteasome inhibitors from preclinical to clinical studies, highlighting their abilities to inhibit the tumor proteasome and induce apoptosis in several human cancers.

  1. Laboratory Monitoring of Parenteral Direct Thrombin Inhibitors. (United States)

    Van Cott, Elizabeth M; Roberts, A Joshua; Dager, William E


    Argatroban and bivalirudin are parenteral direct inhibitors of the activity of thrombin, but, unlike heparin, can inhibit both soluble as well as clot-bound thrombin. These agents do not require antithrombin as a cofactor for activity. The parenteral direct thrombin inhibitors (DTIs) can be used in a variety of settings, including heparin-induced thrombocytopenia (HIT) or an allergy to heparin, and patients requiring anticoagulation for an invasive cardiovascular intervention. Both agents have a relatively short half-life in patients without organ system failure and are typically administered by continuous infusion. Argatroban is primarily eliminated by the liver, while bivalirudin is removed by a combination of proteolytic cleavage by thrombin and renal clearance mechanisms. Several laboratory tests are available for monitoring the anticoagulant effects of the DTIs: the activated partial thromboplastin time (aPTT) and the activated clotting time (ACT) are the most commonly used assays, but on occasion, the thrombin time may be useful. Other coagulation assays such as the dilute thrombin time (dTT), chromogenic anti-IIa assays, and the ecarin clotting time (ECT) can be used. The intensity of anticoagulation with DTIs depends on the indication for use. For patients with HIT, the target aPTT is 1.5 to 3.0 and 1.5 to 2.5 times the patient's baseline value for argatroban and bivalirudin, respectively. DTI anticoagulation used during percutaneous coronary intervention can be measured using ACT. Both DTIs may cause an elevation in the international normalized ratio depending on their plasma concentration. This article will review the use of parenteral DTIs and related laboratory assays for assessing the anticoagulant effect of these drugs. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  2. Proton Pump Inhibitors: Risk for Myopathy? (United States)

    Colmenares, Evan W; Pappas, Ashley L


    The purpose of this article is to describe the relationship between proton pump inhibitors (PPIs) and symptoms of myopathy based on case reports. A literature search was conducted in PubMed (1946 to June 2016) using MeSH terms proton pump inhibitors, omeprazole, esomeprazole, lansoprazole, dexlansoprazole, rabeprazole, pantoprazole, and muscular diseases Additionally, a search was conducted in ToxNet and EMBASE using similar search criteria. The resulting articles were scanned to assess relevance to the review. Bibliographies of all relevant articles were evaluated for additional sources; 26 articles resulted from the search of PubMed, ToxNet, and EMBASE; articles that involved medications typically considered to have myalgia-like side effects (eg, statins), or included patients who presented with a confounding disease state (eg, Guillain-Barré) were excluded. In total, 11 case reports as well as a review of an adverse event reporting database that included 292 cases were evaluated. Association of PPI use and myopathy symptoms does not have a clear etiology. Overall, the available published data do not show a high risk of myopathy with PPI use but should be considered if a patient presents with myopathy symptoms and concurrent PPI use. A limited body of published data suggests that PPI use has been associated with myopathy-like symptoms without long-term effects following discontinuation. Although myopathy is a rare adverse effect observed with PPIs, it can be a serious side effect to be considered when starting a patient on acid suppression therapy. © The Author(s) 2016.

  3. An interesting and efficient green corrosion inhibitor for aluminium ...

    African Journals Online (AJOL)

    An interesting and efficient green corrosion inhibitor for aluminium from extracts of Moringa oleifera in acidic solution. ... The environmentally friendly inhibitor could find possible applications in metal surface anodizing and surface coating in industries. Keywords: Moringa oleifera, Aluminium, Hydrochloric acid, Langmuir ...

  4. Inhibitor for the Corrosion of Mild Steel in H SO

    African Journals Online (AJOL)


    Terminalia chebula, acid corrosion inhibitor, electrochemical polarization, electrochemical impedance spectroscopy, mild steel. 1. Introduction. Large amounts of sulphuric acid are used in the chemical in- dustry for the removal of undesired scale and rust. The addition of corrosion inhibitors effectively protects the metal ...

  5. phytochemicals as green corrosion inhibitors in various corrosive ...

    African Journals Online (AJOL)


    replace toxic inhibitors used for mitigation of corrosion of various metals and alloys in aqueous solutions. Plants represent a class of ... structures causing economic consequences in terms of repair, replacement, product ... Buchweishaija – Physicochemicals as green corrosion inhibitors … 78 rather complex molecular ...

  6. Role of inhibitors and biodegradable material in mitigation of ...

    African Journals Online (AJOL)

    Role of inhibitors and biodegradable material in mitigation of nitrogen losses from fertilized lands. ... Therefore, the economic benefits of reduced environmental pollution and future damage to our environment as a result of the use of urease inhibitors are of higher significance to the production of gains over the long-term.

  7. Phytochemicals as Green Corrosion Inhibitors in Various Corrosive ...

    African Journals Online (AJOL)

    There is an intensive effort underway to develop new plant origin corrosion inhibitors for metal subjected to various environmental conditions. These efforts have been motivated by the desire to replace toxic inhibitors used for mitigation of corrosion of various metals and alloys in aqueous solutions. Plants represent a class ...

  8. Differential expression of cysteine protease inhibitor (CPI) gene of ...

    African Journals Online (AJOL)



    Mar 8, 2012 ... A cDNA clone which encodes a cysteine protease inhibitor gene, named PsCPI, has been identified in. Polygonum ... Keywords: Polygonum sibiricum Laxm., Polygonum sibiricum Laxm cysteine protease inhibitor, rapid amplification of .... Plasmids containing the insert were purified (Promega minipreps) ...

  9. Protein C Inhibitor-A Novel Antimicrobial Agent

    NARCIS (Netherlands)

    Malmström, E.; Mörgelin, M.; Malmsten, M.; Johansson, L.; Norrby-Teglund, A.; Shannon, O.; Schmidtchen, A.; Meijers, J.C.M.; Herwald, H.


    Protein C inhibitor (PCI) is a heparin-binding serine proteinase inhibitor belonging to the family of serpin proteins. Here we describe that PCI exerts broad antimicrobial activity against bacterial pathogens. This ability is mediated by the interaction of PCI with lipid membranes, which

  10. Green ICT drivers and inhibitors perceived by the Czech SMEs

    Directory of Open Access Journals (Sweden)

    Alena Buchalcevova


    Full Text Available With regard to minimizing negative ICT impacts, a number of Green ICT initiatives have been raised. This article presents selected results of a survey conducted in the Czech SMEs that show which drivers and inhibitors influence Green ICT diffusion. First, drivers and inhibitors of Green ICT diffusion are established. Then, the survey results are discussed.

  11. HIV-1 integrase inhibitors as new components of antiviral therapy

    Energy Technology Data Exchange (ETDEWEB)

    Prikazchikova, T A; Aleksandrov, D A; Gottikh, M B [A. N. Belozersky Institute of Physico-Chemical Biology, M. V. Lomonosov Moscow State University, Moscow (Russian Federation); Sycheva, A M; Agapkina, Y Y [Department of Chemistry, M.V. Lomonosov Moscow State University, Moscow (Russian Federation)


    Structural and functional features of HIV-1 integrase are considered and the state of the art in the quest for effective inhibitors of this enzyme is reported. The major classes of integrase inhibitors with known mechanisms of action as well as their in vitro and in vivo inhibitory activities are presented.

  12. Detecting and treating breast cancer resistance to EGFR inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Moonlee, Sun-Young; Bissell, Mina J.; Furuta, Saori; Meier, Roland; Kenny, Paraic A.


    The application describes therapeutic compositions and methods for treating cancer. For example, therapeutic compositions and methods related to inhibition of FAM83A (family with sequence similarity 83) are provided. The application also describes methods for diagnosing cancer resistance to EGFR inhibitors. For example, a method of diagnosing cancer resistance to EGFR inhibitors by detecting increased FAM83A levels is described.

  13. Hepatocyte growth factor activator inhibitor-2 prevents shedding of matriptase

    DEFF Research Database (Denmark)

    Larsen, Brian R; Steffensen, Simon D R; Nielsen, Nis Valentin Ladefoged


    Hepatocyte growth factor activator inhibitor-2 (HAI-2) is an inhibitor of many proteases in vitro, including the membrane-bound serine protease, matriptase. Studies of knock-out mice have shown that HAI-2 is essential for placental development only in mice expressing matriptase, suggesting that HAI...

  14. Early Pregnancy Plasminogen Activator Inhibitor-1 Levels in ...

    African Journals Online (AJOL)


    Apr 25, 2016 ... inhibitor-1 (PAI-1) in normal pregnancy and preeclampsia and determined its relationship with disease ... its clinical utility. KEYWORDS: Disease severity, plasminogen activator inhibitor-1, preeclampsia, pregnancy ..... management of early-onset severe hypertensive disorders of pregnancy. Am J Obstet ...

  15. Role of Protease-Inhibitors in Ocular Diseases

    Directory of Open Access Journals (Sweden)

    Nicola Pescosolido


    Full Text Available It has been demonstrated that the balance between proteases and protease-inhibitors system plays a key role in maintaining cellular and tissue homeostasis. Indeed, its alteration has been involved in many ocular and systemic diseases. In particular, research has focused on keratoconus, corneal wounds and ulcers, keratitis, endophthalmitis, age-related macular degeneration, Sorsby fundus dystrophy, loss of nerve cells and photoreceptors during optic neuritis both in vivo and in vitro models. Protease-inhibitors have been extensively studied, rather than proteases, because they may represent a therapeutic approach for some ocular diseases. The protease-inhibitors mainly involved in the onset of the above-mentioned ocular pathologies are: α2-macroglobulin, α1-proteinase inhibitor (α1-PI, metalloproteinase inhibitor (TIMP, maspin, SERPINA3K, SERPINB13, secretory leukocyte protease inhibitor (SLPI, and calpeptin. This review is focused on the several characteristics of dysregulation of this system and, particularly, on a possible role of proteases and protease-inhibitors in molecular remodeling that may lead to some ocular diseases. Recently, researchers have even hypothesized a possible therapeutic effect of the protease-inhibitors in the treatment of injured eye in animal models.

  16. Trypsin Inhibitor Activity and Condensed Tannin Content in ...

    African Journals Online (AJOL)


    antinutrients trypsin inhibitor activity and condensed tannin content in nine landraces of bambara groundnut grown in three Southern African countries, ... nutrition is limited by antinutrients such as trypsin inhibitors and condensed tannins .... dry heat also need thorough investigations to determine if they are efficient in ...

  17. Effect of biocides and anionic homopolymeric inhibitors on the ...

    African Journals Online (AJOL)

    This paper describes the effect of biocides and of the anionic homopolymeric inhibitors on the precipitation behavior of calcium fluoride (CaF2).The efficiency of inhibitors in the presence and absence of biocides was calculated using the half-life (t1/2) approach, where 50% of the concentration has been precipitated.

  18. A Holistic In silico Approach to Develop Novel Inhibitors Targeting ...

    African Journals Online (AJOL)

    generated model was used for molecular docking simulation studies for predicting the best natural dual inhibitors, the selected inhibitors were ... from medicinal plants were retrieved from previous extensive literature studies [12,13], ... FDA approval, they did not require pre-clinical trials. DrugBank is a comprehensive, high-.

  19. Protease inhibitors, part 13: Specific, weakly basic thrombin inhibitors incorporating sulfonyl dicyandiamide moieties in their structure. (United States)

    Clare, B W; Scozzafava, A; Supuran, C T


    A series of compounds has been prepared by reaction of dicyandiamide with alkyl/arylsulfonyl halides as well as arylsulfonylisocyanates to locate a lead for obtaining weakly basic thrombin inhibitors with sulfonyldicyandiamide moieties as the S1 anchoring group. The detected lead was sulfanilyl-dicyandiamide (K1 of 3 microM against thrombin, and 15 microM against trypsin), which has been further derivatized at the 4-amino group by incorporating arylsulfonylureido as well as amino acyl/dipeptidyl groups protected at the amino terminal moiety with benzyloxycarbonyl or tosylureido moieties. The best compound obtained (ts-D-Phe-Pro-sulfanilyl-dicyandiamide) showed inhibition constants of 9 nM against thrombin and 1400 nM against trypsin. pKa measurements showed that the new derivatives reported here do indeed possess a reduced basicity, with the pKa of the modified guanidine moieties in the range 7.9-8.3 pKa units. Molecular mechanics calculations showed that the preferred tautomeric form of these compounds is of the type ArSO2N=C(NH2) NH-CN, probably allowing for the formation of favorable interaction between this new anchoring group and the active site amino acid residue Asp 189, critical for substrate/inhibitor binding to this type of serine protease. Thus, the main finding of the present paper is that the sulfonyldicyandiamide group may constitute an interesting alternative for obtaining weakly basic, potent thrombin inhibitors, which bind with less affinity to trypsin.

  20. Characterization of inhibitor(s) of β-glucuronidase enzyme activity in GUS-transgenic wheat

    KAUST Repository

    Ramadan, Ahmed M Ali


    The uidA gene, encoding for β-glucuronidase (GUS), is the most frequently used reporter gene in plants. As a reporter enzyme, GUS can be assayed both qualitatively and quantitatively. In wheat, there are numerous reports of failure in detecting GUS enzyme activity in tissues of transgenic plants, while other reports have suggested presence of β-glucuronidase inhibitor(s) in wheat tissues. In the present study, we show that the β-glucuronidase enzyme activity is not only tissue-specific but also genotype-dependent. Our data demonstrate that the glucuronic acid could be the candidate inhibitor for β-glucuronidase enzyme activity in wheat leaves and roots. It should be noted that the assays to detect β-glucuronidase enzyme activity in wheat should be interpreted carefully. Based on the data of our present study, we recommend studying the chemical pathways, the unintended effects and the possible loss-of-function of any candidate transgene prior to transformation experiments. © 2011 Springer Science+Business Media B.V.

  1. Recent Natural Corrosion Inhibitors for Mild Steel: An Overview

    Directory of Open Access Journals (Sweden)

    Marko Chigondo


    Full Text Available Traditionally, reduction of corrosion has been managed by various methods including cathodic protection, process control, reduction of the metal impurity content, and application of surface treatment techniques, as well as incorporation of suitable alloys. However, the use of corrosion inhibitors has proven to be the easiest and cheapest method for corrosion protection and prevention in acidic media. These inhibitors slow down the corrosion rate and thus prevent monetary losses due to metallic corrosion on industrial vessels, equipment, or surfaces. Inorganic and organic inhibitors are toxic and costly and thus recent focus has been turned to develop environmentally benign methods for corrosion retardation. Many researchers have recently focused on corrosion prevention methods using green inhibitors for mild steel in acidic solutions to mimic industrial processes. This paper provides an overview of types of corrosion, corrosion process, and mainly recent work done on the application of natural plant extracts as corrosion inhibitors for mild steel.

  2. The safety of proton pump inhibitors in pregnancy

    DEFF Research Database (Denmark)

    Nielsen, Gunnar Lauge; Sørensen, Henrik Toft; Thulstrup, Ane Marie


    AIM: To assess the safety of proton pump inhibitors during pregnancy. METHODS: Fifty-one pregnant women exposed to proton pump inhibitors around the time of conception or during pregnancy were compared with 13 327 controls without exposure to any prescribed drug in a population-based study based...... on The Pharmaco-Epidemiological Prescription Database of North Jutland and the Danish Hospital Discharge Registry. RESULTS: Three babies with malformations were found among 38 women exposed to proton pump inhibitors from 30 days before conception to the end of the first trimester. No cases of stillbirth were...... birth weight or number of preterm deliveries in pregnancies exposed to proton pump inhibitors. However, further monitoring is warranted in order to establish or rule out a potential association between the use of proton pump inhibitors and increased risk of either cardiac malformations or preterm birth....

  3. The regulatory beta-subunit of protein kinase CK2 accelerates the degradation of CDC25A phosphatase through the checkpoint kinase Chk1

    DEFF Research Database (Denmark)

    Kreutzer, Jan Nicolas; Guerra, Barbara


    Human CDC25 phosphatases play an important role in cell cycle regulation by removing inhibitory phosphate groups on cyclin-CDKs. Chk1 has been shown to phosphorylate CDC25 family members down-regulating their phosphatase activity through distinct mechanisms. The kinase activity of Chk1 is evident...

  4. Structural basis of regulation and substrate specificity of protein kinase CK2 deduced from the modeling of protein-protein interactions

    Directory of Open Access Journals (Sweden)

    Srinivasan N


    Full Text Available Abstract Background Protein Kinase Casein Kinase 2 (PKCK2 is an ubiquitous Ser/Thr kinase expressed in all eukaryotes. It phosphorylates a number of proteins involved in various cellular processes. PKCK2 holoenzyme is catalytically active tetramer, composed of two homologous or identical and constitutively active catalytic (α and two identical regulatory (β subunits. The tetramer cannot phosphorylate some substrates that can be phosphorylated by PKCK2α in isolation. The present work explores the structural basis of this feature using computational analysis and modeling. Results We have initially built a model of PKCK2α bound to a substrate peptide with a conformation identical to that of the substrates in the available crystal structures of other kinases complexed with the substrates/ pseudosubstrates. In this model however, the fourth acidic residue in the consensus pattern of the substrate, S/T-X-X-D/E where S/T is the phosphorylation site, did not result in interaction with the active form of PKCK2α and is highly solvent exposed. Interaction of the acidic residue is observed if the substrate peptide adopts conformations as seen in β turn, α helix, or 310 helices. This type of conformation is observed and accommodated well by PKCK2α in calmodulin where the phosphorylation site is at the central helix. PP2A carries sequence patterns for PKCK2α phosphorylation. While the possibility of PP2A being phosphorylated by PKCK2 has been raised in the literature we use the model of PP2A to generate a model of PP2A-PKCK2α complex. PKCK2β undergoes phosphorylation by holoenzyme at the N-terminal region, and is accommodated very well in the limited space available at the substrate-binding site of the holoenzyme while the space is insufficient to accommodate the binding of PP2A or calmodulin in the holoenzyme. Conclusion Charge and shape complimentarity seems to play a role in substrate recognition and binding to PKCK2α, along with the consensus pattern. The detailed conformation of the substrate peptide binding to PKCK2 differs from the conformation of the substrate/pseudo substrate peptide that is bound to other kinases in the crystal structures reported. The ability of holoenzyme to phosphorylate substrate proteins seems to depend on the accessibility of the P-site in limited space available in holoenzyme.

  5. Phosphorylation of murine double minute clone 2 (MDM2) protein at serine-267 by protein kinase CK2 in vitro and in cultured cells

    DEFF Research Database (Denmark)

    Hjerrild, M; Milne, D; Dumaz, N


    Murine double minute clone 2 oncoprotein (MDM2) is a key component in the regulation of the tumour suppressor p53. MDM2 mediates the ubiqutination of p53 in the capacity of an E3 ligase and targets p53 for rapid degradation by the proteasome. Stress signals which impinge on p53, leading to its......,6-dichlororibofuranosylbenzimidazole. Radiolabelling of cells expressing tagged recombinant wild-type MDM2 or a S267A (Ser(267)-->Ala) mutant, followed by phosphopeptide analysis, confirmed that Ser(267) is a cellular target for phosphorylation. Ser(267) mutants are still able to direct the degradation of p53, but in a slightly...

  6. Nonnucleoside Reverse-transcriptase Inhibitor- vs Ritonavir-boosted Protease Inhibitor-based Regimens for Initial Treatment of HIV Infection

    DEFF Research Database (Denmark)

    Borges, Álvaro H; Lundh, Andreas; Tendal, Britta


    BACKGROUND: Previous studies suggest that nonnucleoside reverse-transcriptase inhibitors (NNRTIs) cause faster virologic suppression, while ritonavir-boosted protease inhibitors (PI/r) recover more CD4 cells. However, individual trials have not been powered to compare clinical outcomes. METHODS: ...

  7. Dissociable effects of acetylcholinesterase inhibitors and phosphodiesterase type 5 inhibitors on object recognition memory: acquisition versus consolidation

    NARCIS (Netherlands)

    Prickaerts, L.; Sik, A.; Staay, van der F.J.; Vente, de J.; Blokland, A.


    Rationale Phosphodiesterase enzyme type 5 (PDE5) inhibitors and acetylcholinesterase (AChE) inhibitors have cognition-enhancing properties. However, it is not known whether these drug classes affect the same memory processes. Objective We investigated the memory-enhancing effects of the PDE5

  8. Modulation of transcriptional mineralocorticoid receptor activity by casein kinase 2. (United States)

    Ruhs, Stefanie; Strätz, Nicole; Quarch, Katja; Masch, Antonia; Schutkowski, Mike; Gekle, Michael; Grossmann, Claudia


    The pathogenesis of cardiovascular diseases is a multifunctional process in which the mineralocorticoid receptor (MR), a ligand-dependent transcription factor, is involved as proven by numerous clinical studies. The development of pathophysiological MR actions depends on the existence of additional factors e.g. inflammatory cytokines and seems to involve posttranslational MR modifications e.g. phosphorylation. Casein kinase 2 (CK2) is a ubiquitously expressed multifunctional serine/threonine kinase that can be activated under inflammatory conditions as the MR. Sequence analysis and inhibitor experiments revealed that CK2 acts as a positive modulator of MR activity by facilitating MR-DNA interaction with subsequent rapid MR degradation. Peptide microarrays and site-directed mutagenesis experiments identified the highly conserved S459 as a functionally relevant CK2 phosphorylation site of the MR. Moreover, MR-CK2 protein-protein interaction mediated by HSP90 was shown by co-immunoprecipitation. During inflammation, cytokine stimulation led to a CK2-dependent increased expression of proinflammatory genes. The additional MR activation by aldosterone during cytokine stimulation augmented CK2-dependent NFκB signaling which enhanced the expression of proinflammatory genes further. Overall, in an inflammatory environment the bidirectional CK2-MR interaction aggravate the existing pathophysiological cellular situation.

  9. Steroid 5alpha-reductase inhibitors. (United States)

    Flores, Eugenio; Bratoeff, Eugene; Cabeza, Marisa; Ramirez, Elena; Quiroz, Alexandra; Heuze, Ivonne


    The objective of this study is to synthesize new steroidal compounds based on the progesterone skeleton with a high inhibitory activity for the enzyme 5alpha-reductase. Presently similar compounds are being used for the treatment of androgen dependent diseases such as: hirsutism, androgenic alopecia, bening prostatic hyperplasia and prostate cancer. Dihydrotestosterone 2 (Fig. (1)), a 5alpha-reduced metabolite of testosterone 1 has been implicated as a causative factor in the progression of these diseases, largely through the clinical evaluation of males who are genetically deficient of steroid 5alpha-reductase enzyme. As a result of this study, the inhibition of this enzyme has become a pharmacological strategy for the design and synthesis of new antiandrogenic drugs. The advent of finasteride 8 (Fig. (4)) a 5alpha-reductase inhibitor has grately alleviated the symptoms associated with benign prostatic hyperplasia. In our laboratory we recently synthesized several new 16beta-methyl-pregnadiene-3,20-diones derivatives 27 (Fig.(6)), 38-42 (Fig. (11)), 16beta-phenyl-pregnadiene-3,17a-dione derivatives 32-33 (Fig. (7)), 16beta-phenyl-pregnatriene-3,17a-diones, 30, 31 (Fig. (7)) and 16beta-methyl-pregnatriene-3,20-diones 43-46 (Fig. (11)). These compounds were evaluated as 5alpha-reductase inhibitors in the following biological models: Penicillium crustosum broths, the flank organs of gonadectomized male hamsters, the incorporation of radiolabeled sodium acetate into lipids, the effect of the new steroids on the reduction of the weight of the seminal vesicles and on the in vitro metabolism of [(3)H]T to [(3)H]DHT in seminal vesicles homogenates of gonadectomized male hamsters. All trienones 30, 31, and 43-46 in all biological models showed consistently a higher 5alpha-reductase inhibitory activity than the corresponding dienones 27, 32, 33 and 38-42. We believe that with these compounds the 5alpha-reductase enzyme is inactivated by an irreversible Michael type addition

  10. Aromatase inhibitors in stimulated IVF cycles

    Directory of Open Access Journals (Sweden)

    Tournaye Herman


    Full Text Available Abstract Aromatase inhibitors have been introduced as a new treatment modality that could challenge clomiphene citrate as an ovulation induction regiment in patients with PCOS. Although several randomized trials have been conducted regarding their use as ovulation induction agents, only few trials are available regarding their efficacy in IVF stimulated cycles. Current available evidence support that letrozole may have a promising role in stimulated IVF cycles, either when administered during the follicular phase for ovarian stimulation. Especially for women with poor ovarian response, letrozole appears to have the potential to increase clinical pregnancy rates when combined with gonadotropins, whereas at the same time reduces the total gonadotropin dose required for ovarian stimulation. However, given that in all of the trials letrozole has been administered in GnRH antagonist cycles, it is intriguing to test in the future how it may perform when used in GnRH agonist cycles. Finally administration of letrozole during luteal phase in IVF cycles offers another treatment modality for patients at high risk for OHSS taking into account that it drastically reduces estradiol levels

  11. Potential lipase inhibitors from Chinese medicinal herbs. (United States)

    Fei, Hongqiang; Li, Mengxuan; Liu, Wenjun; Sun, Lin; Li, Na; Cao, Liang; Meng, Zhaoqing; Huang, Wenzhe; Ding, Gang; Wang, Zhenzhong; Xiao, Wei


    Obesity has become a major health concern, and it places both personal and economic burdens on the world's population. Traditional Chinese medicinal herbs are rich source of lead compounds and are possible drug candidates, which may be used to treat this condition. This study screened potent pancreatic lipase inhibitors found in traditional Chinese medicinal herbs for ability to treat obesity. A porcine pancreatic lipase inhibition assay was established, and the inhibitory activity of 35 traditional Chinese medicinal herbs was evaluated at a concentration of 200 μg/mL. Two elutions of herbal extracts with strong lipase inhibitory activity were further fractionated by preparative high-performance liquid chromatography into 22 sub-fractions each, and these sub-fractions were tested for anti-lipase activity. Sub-fractions, which exhibited strong lipase inhibitory activity, were continuously fractionated into individual compounds. Two active compounds with potent anti-lipase activity were finally isolated and identified from two traditional Chinese medicinal herbs, respectively. Among 35 traditional Chinese medicinal herbs, the 95% ethanol elutions of Panax notoginseng (Burk.) F.H. Chen (Araliaceae) and Magnolia officinalis Rehd. et Wils (Magnoliaceae) showed strong anti-lipase activity. Two compounds, including 20(S)-ginsenoside Rg3 and honokiol were identified using bioactivity-guided isolation with IC50 = 33.7 and 59.4 μg/mL, respectively. 20(S)-ginsenoside Rg3 and honokiol might be suitable candidates for the treatment of obesity.

  12. Tyrosine kinase inhibitors in hematological malignancies

    Directory of Open Access Journals (Sweden)

    Kamila Kosior


    Full Text Available Recently novel treatment modalities has focused on targeted therapies. Tyrosine kinases represent a good target for cancer treatment since they are involved in transferring phosphate groups from ATP to tyrosine residues in specific substrate proteins transducing intracellular signals engaged in the many mechanisms, playing an important role in the modulation of growth factors signaling that are strongly related to carcinogenesis. Deregulation of tyrosine kinases activity was also found in hematological malignancies, particularly overexpression of tyrosine kinases was observed in chronic myeloid leukemia or acute lymphoblastic leukemia. Herein we show that tyrosine kinase inhibitors have revolutionized hematology malignancies therapy in a very short period of time and they still remain one of the most interesting anticancer compounds that could give a hope for cure and not only long-lasting complete remission. This manuscript summarizes current view on the first generation tyrosine kinase inhibititor – imatinib, second generation – dasatinib, nilotinib and bosutnib as well as new generation tyrosine kinase inhibititors – ponatinib and danusertib in hematooncology.

  13. Acquired Factor VIII Inhibitors: Three Cases

    Directory of Open Access Journals (Sweden)

    Tay Za Kyaw


    Full Text Available Acquired hemophilia A is a rare, but devastating bleeding disorder caused by spontaneous development of autoantibodies directed against coagulation factor VIII. In 40%-50% of patients it is associated with such conditions as the postpartum period, malignancy, use of medications, and autoimmune diseases; however, its cause is unknown in most cases. Acquired hemophilia A should be suspected in patients that present with a coagulation abnormality, and a negative personal and family history of bleeding. Herein we report 3 patients with acquired hemophilia A that had different underlying pathologies, clinical presentations, and therapeutic responses. Factor VIII inhibitor formation in case 1 occurred 6 months after giving birth; underlying disorders were not identified in cases 2 or 3. The bleeding phenotype in these patients’ ranged from no bleeding tendency with isolated prolongation of APTT (activated partial thromboplastin time to severe intramuscular hematoma and hemarthrosis necessitating recombinant activated factor VII infusion and blood components transfusion. Variable responses to immunosuppressive treatment were also observed.

  14. The Azadirachtins: potent insect growth inhibitors

    Directory of Open Access Journals (Sweden)

    Heinz Rembold


    Full Text Available In the course of their coevolution with insects, plants have learnt to protect themselves by chemical means. Semiochemical act as antifeedants or deterrents, others by disrupting growth and development. By use of the Epilachna varivestis bioassay we isolated from Azadirachta indica seed a group of triterpenoids which interfee with larval growth and development in ppm range. Main components are the azadirachtins A and B with identical biological activity. Various other azadirachtins were obtained, either as minor seed components or by chemical modification of the naturally occuring compounds. Structure vs. activity relation studies enabled us to postulate a basic structural element that should still be biologically active and with much simpler chemical structure than natural compounds. What underlies the biological activity of these insect growth inhibitors? Their interference with the hormonal regulation of development and reproduction has been studied in Locusta migratoria and Rhodnius prolixus. In addition, tritiated dihydroazadirachtin A was used. With this approach, a precise correlation between administered dose, resulting effects, and retention of the compound was established. The azadirachtins either interrupt, delay, or deviate whole developmental programs. Results from these studies provide another chemical probe for studies in insect endocrinology and physiology.

  15. Histone deacetylase inhibitors repress chondrosarcoma cell proliferation. (United States)

    Zhu, Jiaxue; Gu, Jianhua; Ma, Jie; Xu, Zhixing; Tao, Hairong


    Due to the high resistance to conventional therapy, there is still no convincingly effective treatment for chondrosarcoma. As a promising new treatment strategy, histone deacetylase inhibitors (HDACIs) have been reported to induce cell arrest, apoptosis and differentiation in some kinds of malignancies, but how HDACi exert their effects on chondrosarcoma is not well understood yet. We investigated the effects of HDACIs trichostatin A (TSA) and sodium valproate (VPA) on chondrosarcoma cells in vitro and in vivo. The cell proliferation and cell cycle were examined in two chondrosarcoma cell lines, SW1353 and JJ012, by MTS and flow cytometry assays, respectively. The in vivo effects of HDACIs were investigated by assessing the chondrosarcoma growth in a mouse xenograft model. Our results showed that TSA and VPA significantly repressed the proliferation of chondrosarcoma cells in a concentration-dependent manner. Flow cytometry indicated that TSA arrested the cell cycle in G2/M phase and VPA arrested the cell cycle in G1 phase. The tumor growth was markedly suppressed in mice treated with TSA and VPA. HDACIs significantly repress the proliferation of chondrosarcoma cells in vitro and in vivo. Our findings imply that HDACIs may provide a novel therapeutic target for the treatment of chondrosarcoma.

  16. α-Glucosidase Inhibitors from Salvia circinata. (United States)

    Flores-Bocanegra, Laura; González-Andrade, Martin; Bye, Robert; Linares, Edelmira; Mata, Rachel


    A dried infusion prepared from the aerial parts of Salvia circinata did not provoke acute toxicity in mice (LD50 > 5 g/kg). This infusion showed poor hypoglycemic and antihyperglycemic effects (100-570 mg/kg) when tested in normal and hyperglycemic mice using acute and oral glucose tolerance tests, respectively. However, this infusion possessed antihyperglycemic action in vivo during an oral sucrose tolerance test (31.6-316 mg/kg), suggesting the presence of α-glucosidase inhibitors in S. circinata. Fractionation of a nonpolar extract of the aerial parts of the plant yielded a new biflavone (1) and four new neoclerodane diterpenoid glucosides (2-5) along with the known compounds amarisolide (6), pedalitin (7), apigenin-7-O-β-d-glucoside (8), and the flavone 2-(3,4-dimethoxyphenyl)-5,6-dihydroxy-7-methoxy-4H-chromen-4-one (9). Compounds 1 and 6-9 were active against mammalian α-glucosidases; 6 and 7 were also active against a recombinant α-glucosidase from Ruminococcus obeum and reduced significantly the postprandial peak during an oral sucrose tolerance test in healthy mice, consistent with their α-glucosidase inhibitory activity. Molecular docking and dynamic studies revealed that compounds 6 and 7 might bind to α-glucosidases at the catalytic center of the enzyme.

  17. CCR5 inhibitors in HIV-1 therapy. (United States)

    Dorr, Patrick; Perros, Manos


    The human immunodeficiency virus 1 (HIV-1) is the causative pathogen of AIDS, the world's biggest infectious disease killer. About 33 million people are infected worldwide, with 2.1 million deaths a year as a direct consequence. The devastating nature of AIDS has prompted widespread research, which has led to an extensive array of therapies to suppress viral replication and enable recovery of the immune system to prolong and improve patient life substantially. However, the genetic plasticity and replication rate of HIV-1 are considerable, which has lead to rapid drug resistance. This, together with the need for reducing drug side effects and increasing regimen compliance, has led researchers to identify antiretroviral drugs with new modes of action. This review describes the discovery and clinical development of CCR5 antagonists and the recent approval of maraviroc as a breakthrough in anti-HIV-1 therapy. CCR5 inhibitors target a human cofactor to disable HIV-1 entry into the cells, and thereby provide a new hurdle for the virus to overcome. The status and expert opinion of CCR5 antagonists for the treatment of HIV-1 infection are detailed.

  18. Suppression of Coronavirus Replication by Cyclophilin Inhibitors

    Directory of Open Access Journals (Sweden)

    Takashi Sasaki


    Full Text Available Coronaviruses infect a variety of mammalian and avian species and cause serious diseases in humans, cats, mice, and birds in the form of severe acute respiratory syndrome (SARS, feline infectious peritonitis (FIP, mouse hepatitis, and avian infectious bronchitis, respectively. No effective vaccine or treatment has been developed for SARS-coronavirus or FIP virus, both of which cause lethal diseases. It has been reported that a cyclophilin inhibitor, cyclosporin A (CsA, could inhibit the replication of coronaviruses. CsA is a well-known immunosuppressive drug that binds to cellular cyclophilins to inhibit calcineurin, a calcium-calmodulin-activated serine/threonine-specific phosphatase. The inhibition of calcineurin blocks the translocation of nuclear factor of activated T cells from the cytosol into the nucleus, thus preventing the transcription of genes encoding cytokines such as interleukin-2. Cyclophilins are peptidyl-prolyl isomerases with physiological functions that have been described for many years to include chaperone and foldase activities. Also, many viruses require cyclophilins for replication; these include human immunodeficiency virus, vesicular stomatitis virus, and hepatitis C virus. However, the molecular mechanisms leading to the suppression of viral replication differ for different viruses. This review describes the suppressive effects of CsA on coronavirus replication.

  19. Efflux inhibitor suppresses Streptococcus mutans virulence properties. (United States)

    Zeng, Huihui; Liu, Jia; Ling, Junqi


    It is well established that efflux pumps play important roles in bacterial pathogenicity and efflux inhibitors (EIs) have been proved to be effective in suppressing bacterial virulence properties. However, little is known regarding the EI of Streptococcus mutans, a well-known caries-inducing bacterium. In this study, we identified the EI of S. mutans through ethidium bromide efflux assay and investigated how EI affected S. mutans virulence regarding the cariogenicity and stress response. Results indicated that reserpine, the identified EI, suppressed acid tolerance, mutacin production and transformation efficiency of S. mutans, and modified biofilm architecture and extracellular polysaccharide distribution. Suppressed glycosyltransferase activity was also noted after reserpine exposure. The data from quantitative real-time-PCR demonstrated that reserpine significantly altered the expression profile of quorum-sensing and virulence-associated genes. These findings suggest that reserpine represents a promising adjunct anticariogenic agent in that it suppresses virulence properties of S. mutans. © FEMS 2017. All rights reserved. For permissions, please e-mail:

  20. α-Glucosidase Inhibitors from Vauquelinia corymbosa

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    Laura Flores-Bocanegra


    Full Text Available The α-glucosidase inhibitory activity of an aqueous extract and compounds from the aerial parts of V. corymbosa was demonstrated with yeast and rat small intestinal α-glucosidases. The aqueous extract inhibited yeast α-glucosidase with a half maximal inhibitory concentration (IC50 of 28.6 μg/mL. Bioassay-guided fractionation of the extract led to the isolation of several compounds, including one cyanogenic glycoside [prunasin (1], five flavonoids [(−-epi-catechin (2, hyperoside (3, isoquercetin (4, quercitrin (5 and quercetin-3-O-(6′′-benzoyl-β-galactoside (6] and two simple aromatic compounds [picein (7 and methylarbutin (8]. The most active compound was 6 with IC50 values of 30 μM in the case of yeast α-glucosidase, and 437 μM in the case of the mammalian enzyme. According to the kinetic analyses performed with rat and yeast enzymes, this compound behaved as mixed-type inhibitor; the calculated inhibition constants (Ki were 212 and 50 μM, respectively. Molecular docking analyses with yeast and mammalian α-glucosidases revealed that compound 6 bind differently to these enzymes. Altogether, the results of this work suggest that preparations of V. corymbosa might delay glucose absorption in vivo.

  1. Proteasome inhibitors therapeutic strategies for cancer. (United States)

    D'Alessandro, Annamaria; Pieroni, Luisa; Ronci, Maurizio; D'Aguanno, Simona; Federici, Giorgio; Urbani, Andrea


    Aberrations in the Ubiquitin-Proteasome System (UPS) have been recently connected to the pathogenesis of several human protein degradation disorders (e.g., cancer and neurodegenerative diseases), so that proteasome is now considered an important target for drug discovery. Small molecules able to inhibit and modulate UPS have been, in fact, described as novel tools for a new approach in anti-cancer therapy. In particular Proteasome Inhibitors (PIs), blocking activation of nuclear factor-kappa B (NF-kB), trigger a decreased cellular proliferation and angiogenic cytokine production, induce cell death and inhibit tumor cell adhesion to stroma. Furthermore, several studies have demonstrated that PIs potentiate the activity of other anti-cancer treatment, in part by down-regulating chemoresistance pathways. Therefore pharmacologic, preclinical, and clinical data suggested the use of PIs in anticancer strategies, for their potential therapeutic relevance in the treatment of cancer and inflammatory-related diseases. This review focuses on recent advances in the development of PIs anticancer agents highlighting both novel patented compounds and novel therapeutic protocol of intervention.

  2. Extraction purification and characterization of trypsin inhibitors from Andean seeds

    Directory of Open Access Journals (Sweden)

    Patricio Castillo


    Full Text Available This work established the conditions of covalent immobilization of trypsin on a Sepharose matrix, which could be applied for the purification of trypsin inhibitors. The higher values of retention of enzymatic activity and immobilized enzymatic activity were obtained with a Sepharose 6B-CL matrix, at room temperature, a pH value of 10.5, an enzymatic load of 25 mg/mL, and a minimum immobilization time of 12 hours, in order to obtain a stable immobilization. The most active trypsin inhibitors were selected through the comparison of, extracts obtained from the seeds of amaranth (Amaranthus caudatus L., pea (Pisum sativum, lupine or “chocho” (Lupinus mutabilis, bean (Phaseolus vulgaris and “sangorache” (Amaranthus hybridus L.. The inhibitors were partially purified using centrifugal ultrafiltration, heat treatment, and TCA precipitation. The permeated and retained fractions of “sangorache” were selected as the most active trypsin inhibitors, and they were selectively purified using affinity chromatography in a Trypsin - Glyoxyl - Sepharose 6B-CL matrix. The kinetic characterization showed the presence of two inhibitors; the first one corresponded to a competitive inhibitor, while the second one behaved as a mixed inhibitor.

  3. 2-Phenylquinazolinones as dual-activity tankyrase-kinase inhibitors. (United States)

    Nkizinkiko, Yves; Desantis, Jenny; Koivunen, Jarkko; Haikarainen, Teemu; Murthy, Sudarshan; Sancineto, Luca; Massari, Serena; Ianni, Federica; Obaji, Ezeogo; Loza, Maria I; Pihlajaniemi, Taina; Brea, Jose; Tabarrini, Oriana; Lehtiö, Lari


    Tankyrases (TNKSs) are enzymes specialized in catalyzing poly-ADP-ribosylation of target proteins. Several studies have validated TNKSs as anti-cancer drug targets due to their regulatory role in Wnt/β-catenin pathway. Recently a lot of effort has been put into developing more potent and selective TNKS inhibitors and optimizing them towards anti-cancer agents. We noticed that some 2-phenylquinazolinones (2-PQs) reported as CDK9 inhibitors were similar to previously published TNKS inhibitors. In this study, we profiled this series of 2-PQs against TNKS and selected kinases that are involved in the Wnt/β-catenin pathway. We found that they were much more potent TNKS inhibitors than they were CDK9/kinase inhibitors. We evaluated the compound selectivity to tankyrases over the ARTD enzyme family and solved co-crystal structures of the compounds with TNKS2. Comparative structure-based studies of the catalytic domain of TNKS2 with selected CDK9 inhibitors and docking studies of the inhibitors with two kinases (CDK9 and Akt) revealed important structural features, which could explain the selectivity of the compounds towards either tankyrases or kinases. We also discovered a compound, which was able to inhibit tankyrases, CDK9 and Akt kinases with equal µM potency.

  4. Clinical development of phosphatidylinositol 3-kinase inhibitors for cancer treatment

    Directory of Open Access Journals (Sweden)

    Brana Irene


    Full Text Available Abstract The phosphatidylinositol 3-kinase (PI3K pathway is commonly deregulated in cancer. In recent years, the results of the first phase I clinical trials with PI3K inhibitors have become available. In comparison to other targeted agents such v-raf murine sarcoma viral oncogene homolog B1 (BRAF inhibitors in melanoma or crizotinib in anaplastic lymphoma receptor tyrosine kinase (ALK translocated tumors, the number of objective responses to PI3K inhibitors is less dramatic. In this review we propose possible strategies to optimize the clinical development of PI3K inhibitors: by exploring the potential role of PI3K isoform-specific inhibitors in improving the therapeutic index, molecular characterization as a basis for patient selection, and the relevance of performing serial tumor biopsies to understand the associated mechanisms of drug resistance. The main focus of this review will be on PI3K isoform-specific inhibitors by describing the functions of different PI3K isoforms, the preclinical activity of selective PI3K isoform-specific inhibitors and the early clinical data of these compounds.

  5. Proteasome inhibitors: recent advances and new perspectives in medicinal chemistry. (United States)

    Genin, E; Reboud-Ravaux, M; Vidal, J


    The search for proteasome inhibitors began fifteen years ago. These inhibitors proved to be powerful tools for investigating many important cellular processes regulated by the ubiquitin-proteasome pathway. Targeting the proteasome pathway can also lead to new treatments for disorders like cancer, muscular dystrophies, inflammation and immune diseases. This is already true for cancer; the FDA approved bortezomib, a potent proteasome inhibitor, for treating multiple myeloma in 2003, and mantle cell lymphoma in 2006. The chemical structures identified in some of the early proteasome inhibitors have led to the development of new anti-cancer drugs (CEP-18770, Carfilzomib, NPI-0052). All these molecules are covalent bonding inhibitors that react with the catalytic Thr1-O(gamma) of the three types of active site. This review covers recent developments in medicinal chemistry of natural and synthetic proteasome inhibitors. Advances in non-covalent inhibitors that have no reactive group will be highlighted as they should minimize side-effects. New structures and new modes of action have been recently identified that open the door to new drug candidates for treating a range of diseases.

  6. Inhibitor development and mortality in non-severe hemophilia A. (United States)

    Eckhardt, C L; Loomans, J I; van Velzen, A S; Peters, M; Mauser-Bunschoten, E P; Schwaab, R; Mazzucconi, M G; Tagliaferri, A; Siegmund, B; Reitter-Pfoertner, S E; van der Bom, J G; Fijnvandraat, K


    The life expectancy of non-severe hemophilia A (HA) patients equals the life expectancy of the non-hemophilic population. However, data on the effect of inhibitor development on mortality and on hemophilia-related causes of death are scarce. The development of neutralizing factor VIII antibodies in non-severe HA patients may dramatically change their clinical outcome due to severe bleeding complications. We assessed the association between the occurrence of inhibitors and mortality in patients with non-severe HA. In this retrospective cohort study, clinical data and vital status were collected for 2709 non-severe HA patients (107 with inhibitors) who were treated between 1980 and 2011 in 34 European and Australian centers. Mortality rates for patients with and without inhibitors were compared. During 64,200 patient-years of follow-up, 148 patients died (mortality rate, 2.30 per 1000 person-years; 95% confidence interval (CI), 1.96-2.70) at a median age of 64 years (interquartile range [IQR], 49-76). In 62 patients (42%) the cause of death was hemophilia related. Sixteen inhibitor patients died at a median age of 71 years (IQR, 60-81). In ten patients the inhibitor was present at time of death; seven of them died of severe bleeding complications. The all-cause mortality rate in inhibitor patients was > 5 times increased compared with that for those without inhibitors (age-adjusted mortality rate ratio, 5.6). Inhibitor development in non-severe hemophilia is associated with increased mortality. High rates of hemophilia-related mortality in this study indicate that non-severe hemophilia is not mild at all and stress the importance of close follow-up for these patients. © 2015 International Society on Thrombosis and Haemostasis.

  7. Corrosion inhibitor mechanisms on reinforcing steel in Portland cement pastes (United States)

    Martin, Farrel James


    The mechanisms of corrosion inhibitor interaction with reinforcing steel are investigated in the present work, with particular emphasis on effects associated with corrosion inhibitors admixed into Portland cement paste. The principal objective in reinforcing steel corrosion inhibition for Portland cement concrete is observed to be preservation of the naturally passive steel surface condition established by the alkaline environment. Introduction of chloride ions to the steel surface accelerates damage to the passive film. Excessive damage to the passive film leads to loss of passivity and a destabilization of conditions that facilitate repair of the passive film. Passive film preservation in presence of chloride ions is achieved either through stabilization of the passive film or by modification of the chemical environment near the steel surface. Availability of inhibitors to the steel surface and their tendency to stabilize passive film defects are observed to be of critical importance. Availability of admixed corrosion inhibitors to the passive film is affected by binding of inhibitors during cement paste hydration. It is determined that pore solution concentrations of inorganic admixed inhibitors tend to be lower than the admixed concentration, while pore solution concentrations of organic admixed inhibitors tend to be higher than the admixed concentration. A fundamental difference of inhibitor function is observed between film-forming and defect stabilizing corrosion inhibitors. Experiments are conducted using coupons of reinforcing steel that are exposed to environments simulating chloride-contaminated Portland cement concrete. A study of the steel/cement paste interface is also performed, and compounds forming at this interface are identified using X-Ray diffraction.

  8. A novel small molecule inhibitor of hepatitis C virus entry.

    Directory of Open Access Journals (Sweden)

    Carl J Baldick

    Full Text Available Small molecule inhibitors of hepatitis C virus (HCV are being developed to complement or replace treatments with pegylated interferons and ribavirin, which have poor response rates and significant side effects. Resistance to these inhibitors emerges rapidly in the clinic, suggesting that successful therapy will involve combination therapy with multiple inhibitors of different targets. The entry process of HCV into hepatocytes represents another series of potential targets for therapeutic intervention, involving viral structural proteins that have not been extensively explored due to experimental limitations. To discover HCV entry inhibitors, we utilized HCV pseudoparticles (HCVpp incorporating E1-E2 envelope proteins from a genotype 1b clinical isolate. Screening of a small molecule library identified a potent HCV-specific triazine inhibitor, EI-1. A series of HCVpp with E1-E2 sequences from various HCV isolates was used to show activity against all genotype 1a and 1b HCVpp tested, with median EC50 values of 0.134 and 0.027 µM, respectively. Time-of-addition experiments demonstrated a block in HCVpp entry, downstream of initial attachment to the cell surface, and prior to or concomitant with bafilomycin inhibition of endosomal acidification. EI-1 was equally active against cell-culture adapted HCV (HCVcc, blocking both cell-free entry and cell-to-cell transmission of virus. HCVcc with high-level resistance to EI-1 was selected by sequential passage in the presence of inhibitor, and resistance was shown to be conferred by changes to residue 719 in the carboxy-terminal transmembrane anchor region of E2, implicating this envelope protein in EI-1 susceptibility. Combinations of EI-1 with interferon, or inhibitors of NS3 or NS5A, resulted in additive to synergistic activity. These results suggest that inhibitors of HCV entry could be added to replication inhibitors and interferons already in development.

  9. Systematic Review on Role of Mammalian Target of Rapamycin Inhibitors as an Alternative to Calcineurin Inhibitors in Renal Transplant: Challenges and Window to Excel. (United States)

    Kumar, Jayant; Bridson, Julie M; Sharma, Ajay; Halawa, Ahmed


    This review focuses on the current limited evidence of graft function and graft survival in various immunosuppressive regimens involving mammalian target of rapamycin inhibitors with or without calcineurin inhibitors. We evaluated the current literature for describing the role of mammalian target of rapamycin inhibitors as an alternative to calcineurin inhibitors by searching the PubMed, EMBASE, Cochrane, Crossref, and Scopus databases using medical subject heading terms. Our detailed analyses of all relevant literature showed use of mammalian target of rapamycin inhibitor-based de novo regimens, early calcineurin inhibitor withdrawal with subsequent introduction of mammalian target of rapamycin inhibitor-based regimens, and late conversion from a calcineurin inhibitor-based regimen to mammalian target of rapamycin inhibitor-based regimens. Notably, early calcineurin inhibitor withdrawal with subsequent introduction of mammalian target of rapamycin inhibitor-based regimen seemed to be a more practical and realistic approach toward immunosuppressive treatment of renal transplant recipients. However, in view of the high rejection rate observed in these studies, it is advisable not to offer these regimens to patients with moderate to high immunologic risk. The present evidences suggest that treatment with mammalian target of rapamycin inhibitors allows early and substantial calcineurin inhibitor minimization. The mammalian target of rapamycin inhibitors everolimus and sirolimus are preferred due to their complementary mechanisms of action and favorable nephrotoxicity profile, which have opened the way for calcineurin inhibitor reduction/withdrawal in the early posttransplant period.

  10. ACE Inhibitor in the treatment of cutaneous and lymphatic sarcoidosis. (United States)

    Kaura, Vinod; Kaura, Samantha H; Kaura, Claire S


    Angiotensin-converting enzyme is used as a marker for sarcoid activity. We describe a case of remission of cutaneous and lymphatic sarcoidosis in a patient treated with an ACE inhibitor for congestive heart failure and hypertension; the remission has continued over 4 years of follow-up. Because this is a report of only one case, there is a possibility of sampling error. Whether the patient's remission in this case was a serendipitous spontaneous remission that happened to occur during ACE inhibitor therapy or whether ACE inhibitor therapy can play a role in the treatment of sarcoidosis needs to be determined in a large clinical trial.

  11. Patented small molecule inhibitors in the ubiquitin proteasome system

    Directory of Open Access Journals (Sweden)

    Colland Frédéric


    Full Text Available Abstract Deregulation of the ubiquitin proteasome system (UPS has been implicated in the pathogenesis of many human diseases, including cancer and neurodegenerative disorders. The recent approval of the proteasome inhibitor Velcade® (bortezomib for the treatment of multiple myeloma and mantle cell lymphoma establishes this system as a valid target for cancer treatment. We review here new patented proteasome inhibitors and patented small molecule inhibitors targeting more specific UPS components, such as E3 ubiquitin ligases and deubiquitylating enzymes. Publication history: Republished from Current BioData's Targeted Proteins database (TPdb;

  12. P3 cap modified Phe*-Ala series BACE inhibitors. (United States)

    Chen, Shu-Hui; Lamar, Jason; Guo, Deqi; Kohn, Todd; Yang, Hsiu-Chiung; McGee, James; Timm, David; Erickson, Jon; Yip, Yvonne; May, Patrick; McCarthy, James


    With the aim of reducing molecular weight and adjusting log D value of BACE inhibitors to more favorable range for BBB penetration and better bioavailability, we synthesized and evaluated several series of P3 cap modified BACE inhibitors obtained via replacement of the P3NHBoc moiety as seen in 3 with other polar functional groups such as amino, hydroxyl and fluorine. Several promising inhibitors emerging from this P3 cap SAR study (e.g., 15 and 19) demonstrated good enzyme inhibitory potencies (BACE-1 IC(50) <50 nM) and whole cell activities (IC(50) approximately 1 microM).

  13. The effect of aromatase inhibitors on bone metabolism

    DEFF Research Database (Denmark)

    Folkestad, Lars; Bjarnason, Nina H; Bjerregaard, Jon Kroll


    Aromatase inhibitors increase the disease-free survival in patients with receptor-positive breast cancer. Aromatase is a cytochrome P450 enzyme complex catalysing the conversion of androgens to oestrogens. These properties cause a significant increase in bone loss. In this MiniReview, we present...... density have shown a significant decrease in bone mineral density of the femoral neck in the aromatase inhibitor groups compared to placebo groups. Placebo-controlled studies lack statistical power to detect changes in fracture incidence; however, aromatase inhibitors increase the incidence of fractures...

  14. Does Mineralocorticoid Receptor Antagonism Prevent Calcineurin Inhibitor-Induced Nephrotoxicity?

    Directory of Open Access Journals (Sweden)

    Line Aas Mortensen


    Full Text Available Calcineurin inhibitors have markedly reduced acute rejection rates in renal transplantation, thus significantly improved short-term outcome. The beneficial effects are, however, tampered by acute and chronic nephrotoxicity leading to interstitial fibrosis and tubular atrophy, which impairs long-term allograft survival. The mineralocorticoid hormone aldosterone induces fibrosis in numerous organs, including the kidney. Evidence from animal models suggests a beneficial effect of aldosterone antagonism in reducing calcineurin inhibitor-induced nephrotoxicity. This review summarizes current evidence of mineralocorticoid receptor antagonism in animal models of calcineurin inhibitor-induced nephrotoxicity and the results from studies of mineralocorticoid antagonism in renal transplant patients.

  15. Template-Based de Novo Design for Type II Kinase Inhibitors and Its Extented Application to Acetylcholinesterase Inhibitors

    Directory of Open Access Journals (Sweden)

    Bo-Han Su


    Full Text Available There is a compelling need to discover type II inhibitors targeting the unique DFG-out inactive kinase conformation since they are likely to possess greater potency and selectivity relative to traditional type I inhibitors. Using a known inhibitor, such as a currently available and approved drug or inhibitor, as a template to design new drugs via computational de novo design is helpful when working with known ligand-receptor interactions. This study proposes a new template-based de novo design protocol to discover new inhibitors that preserve and also optimize the binding interactions of the type II kinase template. First, sorafenib (Nexavar® and nilotinib (Tasigna®, two type II inhibitors with different ligand-receptor interactions, were selected as the template compounds. The five-step protocol can reassemble each drug from a large fragment library. Our procedure demonstrates that the selected template compounds can be successfully reassembled while the key ligand-receptor interactions are preserved. Furthermore, to demonstrate that the algorithm is able to construct more potent compounds, we considered kinase inhibitors and other protein dataset, acetylcholinesterase (AChE inhibitors. The de novo optimization was initiated using a template compound possessing a less than optimal activity from a series of aminoisoquinoline and TAK-285 inhibiting type II kinases, and E2020 derivatives inhibiting AChE respectively. Three compounds with greater potency than the template compound were discovered that were also included in the original congeneric series. This template-based lead optimization protocol with the fragment library can help to design compounds with preferred binding interactions of known inhibitors automatically and further optimize the compounds in the binding pockets.

  16. The structures of human dihydroorotate dehydrogenase with and without inhibitor reveal conformational flexibility in the inhibitor and substrate binding sites. (United States)

    Walse, Björn; Dufe, Veronica Tamu; Svensson, Bo; Fritzson, Ingela; Dahlberg, Leif; Khairoullina, Alfia; Wellmar, Ulf; Al-Karadaghi, Salam


    Inhibitors of dihydroorotate dehydrogenase (DHODH) have been suggested for the treatment of rheumatoid arthritis, psoriasis, autoimmune diseases, Plasmodium, and bacterial and fungal infections. Here we present the structures of N-terminally truncated (residues Met30-Arg396) DHODH in complex with two inhibitors: a brequinar analogue (6) and a novel inhibitor (a fenamic acid derivative) (7), as well as the first structure of the enzyme to be characterized without any bound inhibitor. It is shown that 7 uses the "standard" brequinar binding mode and, in addition, interacts with Tyr356, a residue conserved in most class 2 DHODH proteins. Compared to the inhibitor-free structure, some of the amino acid side chains in the tunnel in which brequinar binds and which was suggested to be the binding site of ubiquinone undergo changes in conformation upon inhibitor binding. Using our data, the loop regions of residues Leu68-Arg72 and Asn212-Leu224, which were disordered in previously studied human DHODH structures, could be built into the electron density. The first of these loops, which is located at the entrance to the inhibitor-binding pocket, shows different conformations in the three structures, suggesting that it may interfere with inhibitor/cofactor binding. The second loop has been suggested to control the access of dihydroorotate to the active site of the enzyme and may be an important player in the enzymatic reaction. These observations provide new insights into the dynamic features of the DHODH reaction and suggest new approaches to the design of inhibitors against DHODH.

  17. Novel orally bioavailable EZH1/2 dual inhibitors with greater antitumor efficacy than an EZH2 selective inhibitor. (United States)

    Honma, Daisuke; Kanno, Osamu; Watanabe, Jun; Kinoshita, Junzo; Hirasawa, Makoto; Nosaka, Emi; Shiroishi, Machiko; Takizawa, Takeshi; Yasumatsu, Isao; Horiuchi, Takao; Nakao, Akira; Suzuki, Keisuke; Yamasaki, Tomonori; Nakajima, Katsuyoshi; Hayakawa, Miho; Yamazaki, Takanori; Yadav, Ajay Singh; Adachi, Nobuaki


    Polycomb repressive complex 2 (PRC2) methylates histone H3 lysine 27 and represses gene expression to regulate cell proliferation and differentiation. Enhancer of zeste homolog 2 (EZH2) or its close homolog EZH1 functions as a catalytic subunit of PRC2, so there are two PRC2 complexes containing either EZH2 or EZH1. Tumorigenic functions of EZH2 and its synthetic lethality with some subunits of SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complexes have been observed. However, little is known about the function of EZH1 in tumorigenesis. Herein, we developed novel, orally bioavailable EZH1/2 dual inhibitors that strongly and selectively inhibited methyltransferase activity of both EZH2 and EZH1. EZH1/2 dual inhibitors suppressed trimethylation of histone H3 lysine 27 in cells more than EZH2 selective inhibitors. They also showed greater antitumor efficacy than EZH2 selective inhibitor in vitro and in vivo against diffuse large B-cell lymphoma cells harboring gain-of-function mutation in EZH2. A hematological cancer panel assay indicated that EZH1/2 dual inhibitor has efficacy against some lymphomas, multiple myeloma, and leukemia with fusion genes such as MLL-AF9, MLL-AF4, and AML1-ETO. A solid cancer panel assay demonstrated that some cancer cell lines are sensitive to EZH1/2 dual inhibitor in vitro and in vivo. No clear correlation was detected between sensitivity to EZH1/2 dual inhibitor and SWI/SNF mutations, with a few exceptions. Severe toxicity was not seen in rats treated with EZH1/2 dual inhibitor for 14 days at drug levels higher than those used in the antitumor study. Our results indicate the possibility of EZH1/2 dual inhibitors for clinical applications. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  18. Phosphodiesterase type 5 inhibitors: unmet needs. (United States)

    Hatzimouratidis, K; Hatzichristou, D G


    Erectile dysfunction (ED) has been revolutionized during the last two decades, as several treatment options are available today. Phosphodiesterase type 5 (PDE5) inhibitors (sildenafil, tadalafil, vardenafil) are currently the first choice treatment option for ED by most physicians and patients due to their high efficacy rates and favourable safety profiles. Despite the fact that more than 50 million ED patients have been treated successfully worldwide with PDE5i several issues remain to be addressed. Patients with severe neurologic damage, diabetes mellitus, or severe vascular disease may be resistant to PDE5i. Inappropriate instructions, lack of follow-up and lack of patient-centered care models have been identified as main reasons for "nonresponse", leading to drop-out rates of even > 50%. Preservation of corporal smooth muscle with chronic administration of PDE5i has been reported and there is a substantial body of evidence for beneficial effects of these drugs on endothelium and cardiovascular function. Finally, improvement of lower urinary symptoms after PDE5i administration has been reported and a possible role on treatment of premature ejaculation has been proposed. Many new PDE5i are candidates to enter the market in the forthcoming years. However, pharmacokinetic differences should be obvious to consider a truly better option for patients. Patients must be aware of all treatment options since no ideal treatment exists and physicians must offer personalized medicine to their patients in the future. The development and adaptation of a patient-centered care model in sexual medicine will increase efficacy and safety of current and future treatments.

  19. Phosphodiesterase type 5 inhibitors: the day after. (United States)

    Hatzimouratidis, Konstantinos; Hatzichristou, Dimitrios


    Review the literature on phosphodiesterase type 5 inhibitors (PDE5-Is), addressing critical issues in their current and future use, assessing unanswered questions, and identifying research needs. A MEDLINE search was conducted on PDE5-Is, with emphasis on clinical trials and experience, for interpretation and analysis of their present and future role. Although approximately 40 million patients with erectile dysfunction have been treated successfully worldwide with the three available PDE5-Is, inappropriate instructions, lack of follow-up, and lack of patient-centered care models are the main reasons for "non-response," leading to drop-out rates of >50%. Patients with severe neurologic damage, diabetes mellitus, or severe vascular disease may be resistant to PDE5-Is. Preservation of corporal smooth muscle with chronic administration of PDE5-Is has been reported and substantial evidence indicates that these drugs have beneficial effects on endothelium and cardiovascular function; sildenafil has been approved for the treatment of idiopathic pulmonary hypertension. Improvement of lower urinary tract symptoms in men with benign prostatic hyperplasia after PDE5-I administration has been also suggested. The data indicate the necessity for (1) exploration of the pharmacologic characteristics of the three PDE5-Is; (2) research on their pharmacologic differences because some actions seems to be drug-specific; (3) development of alternative management strategies, such as chronic, low, everyday doses of PDE5-Is, if the monthly cost is affordable; and (4) clinical trials on use of PDE5-Is to treat other chronic conditions. The door for innovative therapeutic approaches will open, specifically for cross-risk factor treatment with PDE5-Is or their use in combination treatments or new multimodal pills that take advantage of drugs that exert pleiotropic vascular actions.

  20. Proton pump inhibitors affect the gut microbiome. (United States)

    Imhann, Floris; Bonder, Marc Jan; Vich Vila, Arnau; Fu, Jingyuan; Mujagic, Zlatan; Vork, Lisa; Tigchelaar, Ettje F; Jankipersadsing, Soesma A; Cenit, Maria Carmen; Harmsen, Hermie J M; Dijkstra, Gerard; Franke, Lude; Xavier, Ramnik J; Jonkers, Daisy; Wijmenga, Cisca; Weersma, Rinse K; Zhernakova, Alexandra


    Proton pump inhibitors (PPIs) are among the top 10 most widely used drugs in the world. PPI use has been associated with an increased risk of enteric infections, most notably Clostridium difficile. The gut microbiome plays an important role in enteric infections, by resisting or promoting colonisation by pathogens. In this study, we investigated the influence of PPI use on the gut microbiome. The gut microbiome composition of 1815 individuals, spanning three cohorts, was assessed by tag sequencing of the 16S rRNA gene. The difference in microbiota composition in PPI users versus non-users was analysed separately in each cohort, followed by a meta-analysis. 211 of the participants were using PPIs at the moment of stool sampling. PPI use is associated with a significant decrease in Shannon's diversity and with changes in 20% of the bacterial taxa (false discovery rate microbiome of PPI-users, including the genus Rothia (p=9.8×10(-38)). In PPI users we observed a significant increase in bacteria: genera Enterococcus, Streptococcus, Staphylococcus and the potentially pathogenic species Escherichia coli. The differences between PPI users and non-users observed in this study are consistently associated with changes towards a less healthy gut microbiome. These differences are in line with known changes that predispose to C. difficile infections and can potentially explain the increased risk of enteric infections in PPI users. On a population level, the effects of PPI are more prominent than the effects of antibiotics or other commonly used drugs. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to

  1. Prodrugs of herpes simplex thymidine kinase inhibitors. (United States)

    Yanachkova, Milka; Xu, Wei-Chu; Dvoskin, Sofya; Dix, Edward J; Yanachkov, Ivan B; Focher, Federico; Savi, Lida; Sanchez, M Dulfary; Foster, Timothy P; Wright, George E


    Because guanine-based herpes simplex virus thymidine kinase inhibitors are not orally available, we synthesized various 6-deoxy prodrugs of these compounds and evaluated them with regard to solubility in water, oral bioavailability, and efficacy to prevent herpes simplex virus-1 reactivation from latency in a mouse model. Organic synthesis was used to prepare compounds, High Performance Liquid Chromatography (HPLC) to analyze hydrolytic conversion, Mass Spectrometry (MS) to measure oral bioavailability, and mouse latent infection and induced reactivation to evaluate the efficacy of a specific prodrug. Aqueous solubilities of prodrugs were improved, oxidation of prodrugs by animal cytosols occurred in vitro, and oral absorption of the optimal prodrug sacrovir™ (6-deoxy-mCF3PG) in the presence of the aqueous adjuvant Soluplus® and conversion to active compound N(2)-[3-(trifluoromethyl)pheny])guanine (mCF3PG) were accomplished in mice. Treatment of herpes simplex virus-1 latent mice with sacrovir™ in 1% Soluplus in drinking water significantly suppressed herpes simplex virus-1 reactivation and viral genomic replication. Ad libitum oral delivery of sacrovir™ was effective in suppressing herpes simplex virus-1 reactivation in ocularly infected latent mice as measured by the numbers of mice shedding infectious virus at the ocular surface, numbers of trigeminal ganglia positive for infectious virus, number of corneas that had detectable infectious virus, and herpes simplex virus-1 genome copy numbers in trigeminal ganglia following reactivation. These results demonstrate the statistically significant effect of the prodrug on suppressing herpes simplex virus-1 reactivation in vivo. © The Author(s) 2015.

  2. Effect of cholinesterase inhibitors on attention. (United States)

    Pepeu, Giancarlo; Giovannini, Maria Grazia; Bracco, Laura


    Advantages and limits of the use of cholinesterase inhibitors (ChEI) in Alzheimer's disease (AD) are well established. Their effects result from an increase in extracellular acetylcholine (ACh) whose hydrolysis is prevented by cholinesterase inhibition. In this way, the cholinergic deficit which characterizes AD may be corrected. This overview discusses which components of the cognitive process are improved by ChEI administration. In animal experiments, the increase in ACh release, detected in brain areas during behavioral tasks designed to tax attentional processes, demonstrates that an activation of cholinergic neurons underlies arousal and attention. Since arousal and attention depend on activation of the forebrain cholinergic system, it is to be expected that the loss of cholinergic neurons occurring in AD may lead to impairment of the attentional processes. Indeed, a consensus exists that attention is the first non-memory domain to be affected in AD, before deficits in language and visuo-spatial functions. The difficulties with daily living, which occur even in mild AD, may be related to attentional deficits. ChEIs, by restoring the cholinergic activity, should improve attention. If the cognitive changes resulting from ChEI treatment in AD patients are assessed with appropriate tests or selected items of the scales, a predominant effect on attention and executive functions emerges. In a group of 121 subjects with mild to moderate AD, (MMSE score 21.88 ± 3.63) followed in the Alzheimer Unit in Florence, after a year of treatment with standard doses of ChEIs, it was observed a stabilization of the disease, characterized by no changes of the tests evaluating attention and executive functions but a worsening of those involving memory mechanisms. These findings suggest that ChEI treatment preserves attention more than memory. Finally, the electrophysiological and neurochemical mechanisms through which the activation of the cholinergic forebrain neurons enhance

  3. Chelation: a fundamental mechanism of action of AGE inhibitors, AGE breakers, and other inhibitors of diabetes complications. (United States)

    Nagai, Ryoji; Murray, David B; Metz, Thomas O; Baynes, John W


    This article outlines evidence that advanced glycation end product (AGE) inhibitors and breakers act primarily as chelators, inhibiting metal-catalyzed oxidation reactions that catalyze AGE formation. We then present evidence that chelation is the most likely mechanism by which ACE inhibitors, angiotensin receptor blockers, and aldose reductase inhibitors inhibit AGE formation in diabetes. Finally, we note several recent studies demonstrating therapeutic benefits of chelators for diabetic cardiovascular and renal disease. We conclude that chronic, low-dose chelation therapy deserves serious consideration as a clinical tool for prevention and treatment of diabetes complications.

  4. Histone deacetylase inhibitors in the treatment of lymphoma. (United States)

    Lemoine, Manuela; Younes, Anas


    Histone deacetylases (HDACs) play an important role in the regulation of gene expression. In addition to histones, HDACs can modulate the function of many other proteins involved in the regulation of cell survival and proliferation, angiogenesis, inflammation, and immunity. Deregulated HDACs have been shown to be commonly associated with many types of cancer, and are considered promising targets for cancer therapy. Several HDAC inhibitors are in clinical trials as monotherapies or in combination with other anticancer agents, but only two such inhibitors -- vorinostat (suberoylanilide hydroxamic acid) and romidepsin (depsipeptide) -- have been approved by the US Food and Drug Administration for treating relapsed cutaneous T-cell lymphoma. Other HDAC inhibitors, such as belinostat (PXD101), mocetinostat (MGCD0103), entinostat (SNDX-275), and panobinostat (LBH589), are currently in clinical development. This review focuses on the use of HDAC inhibitors in the treatment of relapsed lymphoma.

  5. Proton Pump Inhibitors in Pediatrics: Relevant Pharmacokinetics and Pharmacodynamics

    National Research Council Canada - National Science Library

    Kearns, Gregory L; Winter, Harland S


    A marked discordance between the disposition of proton pump inhibitors (PPIs) in plasma and the kinetics of effect suggests the need for new approaches to characterize the clinical pharmacology of PPIs in infants and children...

  6. Proteasome inhibitors as experimental therapeutics of autoimmune diseases

    NARCIS (Netherlands)

    Verbrugge, C.S.E.; Scheper, R.J.; Lems, W.F.; de Gruijl, T.D.; Jansen, G.


    Current treatment strategies for rheumatoid arthritis (RA) consisting of disease-modifying anti-rheumatic drugs or biological agents are not always effective, hence driving the demand for new experimental therapeutics. The antiproliferative capacity of proteasome inhibitors (PIs) has received

  7. Morphological effects of MMPs inhibitors on the dentin bonding

    National Research Council Canada - National Science Library

    Li, He; Li, Tianbo; Li, Xiuying; Zhang, Zhimin; Li, Penglian; Li, Zhenling


    Matrix metalloproteinases (MMPs) have been studied extensively, and MMP inhibitors have been used as dental pretreatment agents prior to dentin bonding because they reduce collagen fiber degradation and improve bonding strength...

  8. Identification of urine metabolites of TFAP, a cyclooxygenase-1 inhibitor. (United States)

    Kakuta, Hiroki; Fukai, Ryosuke; Xiaoxia, Zheng; Ohsawa, Fuminori; Bamba, Takeshi; Hirata, Kazumasa; Tai, Akihiro


    Only a few COX-1-selective inhibitors are currently available, and the research on COX-1 selective inhibitors is not fully developed. The authors have produced several COX-1 selective inhibitors including N-(5-amino-2-pyridinyl)-4-trifluoromethylbenzamide: TFAP (3). Although 3 shows potent analgesic effect without gastric damage, the urine after administration of 3 becomes red-purple. Since the colored-urine should be avoided for clinical use, in this research we examined the cause of the colored-urine. UV-vis spectra and LC-MS/MS analyses of urine samples and metabolite candidates of 3 were performed to afford information that the main reason of the colored urine is a diaminopyridine (4), produced by metabolization of 3. This information is useful to design new COX-1 selective inhibitors without colored urine based on the chemical structure of 3. Copyright 2010 Elsevier Ltd. All rights reserved.

  9. Inhibitor for the Corrosion of Mild Steel in H SO

    African Journals Online (AJOL)


    electron microscopic studies provided confirmatory evidence of an improved surface condition, due to adsorption, for corrosion protection. KEYWORDS. Terminalia chebula, acid corrosion inhibitor, electrochemical polarization, electrochemical impedance spectroscopy, mild steel. 1. Introduction. Large amounts of sulphuric ...


    Directory of Open Access Journals (Sweden)

    A E Karateev


    Full Text Available The paper provides the clinical characteristics of etoricoxib (Arcoxia, a new selective cyclooxygenase-2 inhibitor having unique properties, which permits it to be distinguished among other nonsteroidal anti-inflammatory agents.


    Directory of Open Access Journals (Sweden)

    A E Karateev


    Full Text Available The paper provides the clinical characteristics of etoricoxib (Arcoxia, a new selective cyclooxygenase-2 inhibitor having unique properties, which permits it to be distinguished among other nonsteroidal anti-inflammatory agents.

  12. Azorhodanine derivatives as inhibitors for acidic corrosion of nickel. (United States)

    Fouda, Abd El-Aziz S; Al-Sarawy, Ahmed A; Omar, Tark M


    Azorhodanine derivatives (HL1-HL5) were tested as corrosion inhibitors for nickel in 2M HNO3 solution using weight loss and galvanostatic polarization techniques. The results showed that these derivatives act as inhibitors for nickel in this medium. The inhibition was assumed to occur via adsorption of the inhibitor molecule on the metal surface. Polarization measurements indicated that these compounds act as mixed-type inhibitors, but the cathode is more polarized when an external current was applied. This means that these compounds retard the rate of hydrogen evolution and the rate of dissolution of the metal. Results showed that azorhodanine derivatives are adsorbed on the nickel surface following Temkin's adsorption isotherm. The activation energy and thermodynamic parameters were calculated and discussed at different temperatures (30-45 degrees C).

  13. Advances in non-peptidomimetic HIV protease inhibitors. (United States)

    Pang, X; Liu, Z; Zhai, G


    HIV protease plays a crucial role in the viral life cycle. It can cleave a series of heptamers in the viral Gag and GagPol precursor proteins to generate mature infectious virus particles. Successful inhibition of the protease will prevent this maturation step and hence block the spreading of HIV. However, the rapid emergence of drug resistance makes it urgent to develop new HIV protease inhibitors to combat the global disease. Besides, poor oral bioavailability, unacceptable side effects, high treatment cost and pill burden also trouble the application of HIV protease inhibitors. In such situations, non-peptidomimetic HIV protease inhibitors have drawn an increasing interest as a potential therapeutic option due to their small molecular weight, favorable bioavailability, high stability in vivo, low resistance and cost of production. In this review, we present the recent advances in non-peptidomimetic HIV protease inhibitors. Their design strategies, biological activities, resistance profiles, as well as clinical application will also be discussed.

  14. The binding mechanism of a peptidic cyclic serine protease inhibitor

    DEFF Research Database (Denmark)

    Jiang, Longguang; Svane, Anna Sigrid P.; Sørensen, Hans Peter


    Serine proteases are classical objects for studies of catalytic and inhibitory mechanisms as well as interesting as therapeutic targets. Since small-molecule serine protease inhibitors generally suffer from specificity problems, peptidic inhibitors, isolated from phage-displayed peptide libraries......, have attracted considerable attention. Here, we have investigated the mechanism of binding of peptidic inhibitors to serine protease targets. Our model is upain-1 (CSWRGLENHRMC), a disulfide-bond-constrained competitive inhibitor of human urokinase-type plasminogen activator with a noncanonical...... kinetics and thermodynamics by surface plasmon resonance and isothermal titration calorimetry. We found that upain-1 changes both main-chain conformation and side-chain orientations as it binds to the protease, in particular its Trp3 residue and the surrounding backbone. The properties of upain-1...

  15. (GSK3) inhibitor 6-bromoindirubin-3'-oxime (BIO) promotes the ...

    African Journals Online (AJOL)

    GSK3) inhibitors, is a key regulator of many signaling pathways with the capacity to maintain the pluripotency of human and mouse embryonic stem cells (ESCs). Whether BIO can maintain the pluripotency of mouse male germline stem cells ...

  16. SAH derived potent and selective EZH2 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Kung, Pei-Pei; Huang, Buwen; Zehnder, Luke; Tatlock, John; Bingham, Patrick; Krivacic, Cody; Gajiwala, Ketan; Diehl, Wade; Yu, Xiu; Maegley, Karen A.


    A series of novel enhancer of zeste homolog 2 (EZH2) inhibitors was designed based on the chemical structure of the histone methyltransferase (HMT) inhibitor SAH (S-adenosyl-l-homocysteine). These nucleoside-based EZH2 inhibitors blocked the methylation of nucleosomes at H3K27 in biochemical assays employing both WT PRC2 complex as well as a Y641N mutant PRC2 complex. The most potent compound, 27, displayed IC50’s against both complexes of 270 nM and 70 nM, respectively. To our knowledge, compound 27 is the most potent SAH-derived inhibitor of the EZH2 PRC2 complex yet identified. This compound also displayed improved potency, lipophilic efficiency (LipE), and selectivity profile against other lysine methyltransferases compared with SAH.

  17. Purification and Characterization of Human Thrombin Activatable Fibrinolysis Inhibitor (TAFI)

    DEFF Research Database (Denmark)

    Christensen, Trine; Skottrup, Peter Durand; Valnickova, Zuzana

    Thrombin Activatable Fibrinolysis inhibitor (TAFI) is a basic carboxypeptidase, circulating in plasma as an enzymatic inactive precursor. TAFI shares ~40% overall sequence identity with pancreas Carboxypeptidase B (PCPB) with the activation peptide being less conserved. Following activation of TA...

  18. Identification of catechols as histone-lysine demethylase inhibitors

    DEFF Research Database (Denmark)

    Nielsen, Anders L; Kristensen, Line H; Stephansen, Karen B


    Identification of inhibitors of histone-lysine demethylase (HDM) enzymes is important because of their involvement in the development of cancer. An ELISA-based assay was developed for identification of inhibitors of the HDM KDM4C in a natural products library. Based on one of the hits with affinity...... in the low µM range (1, a catechol), a subset of structurally related compounds was selected and tested against a panel of HDMs. In this subset, two inhibitors (2 and 10) had comparable affinities towards KDM4C and KDM6A but no effect on PHF8. One inhibitor restored H3K9me3 levels in KDM4C transfected U2-OS...

  19. Hh signaling inhibitors from Vitex negundo; naturally occurring inhibitors of the GLI1-DNA complex. (United States)

    Arai, Midori A; Fujimatsu, Teruhisa; Uchida, Kyoko; Sadhu, Samir K; Ahmed, Firoj; Ishibashi, Masami


    The hedgehog (Hh) signaling pathway has crucial roles in embryonic development, cell maintenance and proliferation, and is also known to contribute to cancer cell growth. New naturally occurring Hh inhibitors (1, 7 and 9) were isolated from Vitex negundo using our previously constructed cell-based assay. Bioactivity guided isolation provided 9 natural compounds including a new diterpene, nishindanol (9). Compounds 7 and 9 showed cytotoxicity against cancer cell lines in which Hh signaling was aberrantly activated. Vitetrifolin D (7; GLI1 transcriptional inhibition IC50 = 20.2 μM) showed inhibition of Hh related protein (PTCH and BCL2) production. Interestingly, the constructed electrophoresis mobility shift assay revealed that vitetrifolin D (7) disrupted GLI1 binding on its DNA binding domain. epi-Sclareol (8; inactive), possessing a similar structure to 7, did not show inhibition of GLI1–DNA complex formation. This is the first example of naturally occurring inhibitors of GLI1–DNA complex formation.

  20. Morphological effects of MMPs inhibitors on the dentin bonding


    Li, He; Li, Tianbo; Li, Xiuying; Zhang, Zhimin; Li, Penglian; Li, Zhenling


    Matrix metalloproteinases (MMPs) have been studied extensively, and MMP inhibitors have been used as dental pretreatment agents prior to dentin bonding because they reduce collagen fiber degradation and improve bonding strength. However, morphologic characteristics of the collagen network after etching and of the post-adhesive dentin hybrid layers (DHL) after MMP inhibitors pretreatment have not been evaluated. Thus, we investigated demineralized dentin pretreated with chlorhexidine (CHX) and...

  1. New synthetic thrombin inhibitors: molecular design and experimental verification.

    Directory of Open Access Journals (Sweden)

    Elena I Sinauridze

    Full Text Available BACKGROUND: The development of new anticoagulants is an important goal for the improvement of thromboses treatments. OBJECTIVES: The design, synthesis and experimental testing of new safe and effective small molecule direct thrombin inhibitors for intravenous administration. METHODS: Computer-aided molecular design of new thrombin inhibitors was performed using our original docking program SOL, which is based on the genetic algorithm of global energy minimization in the framework of a Merck Molecular Force Field. This program takes into account the effects of solvent. The designed molecules with the best scoring functions (calculated binding energies were synthesized and their thrombin inhibitory activity evaluated experimentally in vitro using a chromogenic substrate in a buffer system and using a thrombin generation test in isolated plasma and in vivo using the newly developed model of hemodilution-induced hypercoagulation in rats. The acute toxicities of the most promising new thrombin inhibitors were evaluated in mice, and their stabilities in aqueous solutions were measured. RESULTS: New compounds that are both effective direct thrombin inhibitors (the best K(I was 1111.1 mg/kg. A plasma-substituting solution supplemented with one of the new inhibitors prevented hypercoagulation in the rat model of hemodilution-induced hypercoagulation. Activities of the best new inhibitors in physiological saline (1 µM solutions were stable after sterilization by autoclaving, and the inhibitors remained stable at long-term storage over more than 1.5 years at room temperature and at 4°C. CONCLUSIONS: The high efficacy, stability and low acute toxicity reveal that the inhibitors that were developed may be promising for potential medical applications.

  2. Small Bowel Angioedema Secondary to Angiotensin-Converting Enzyme Inhibitors (United States)

    Hurairah, Abu


    Small bowel angioedema induced by angiotensin-converting enzyme (ACE) inhibitors is a rare clinicopathologic entity. It frequently poses a diagnostic challenge and is often not recognized before surgical exploration. The present study illustrates that clinical awareness for this condition and adequate use of radiologic investigations can help make the correct diagnosis of ACE inhibitor-associated angioedema, thus avoiding the cost and morbidity associated with unnecessary interventions. PMID:28133581

  3. Small Bowel Angioedema Secondary to Angiotensin-Converting Enzyme Inhibitors


    Inayat, Faisal; Hurairah, Abu


    Small bowel angioedema induced by angiotensin-converting enzyme (ACE) inhibitors is a rare clinicopathologic entity. It frequently poses a diagnostic challenge and is often not recognized before surgical exploration. The present study illustrates that clinical awareness for this condition and adequate use of radiologic investigations can help make the correct diagnosis of ACE inhibitor-associated angioedema, thus avoiding the cost and morbidity associated with unnecessary interventions.

  4. In Silico Design and Evaluation of Carboxylesterase Inhibitors


    Stoddard, Shana V.; Yu, Xiaozhen; Potter, Philip M.; Wadkins, Randy M.


    Carboxylesterases (CEs) are important enzymes that catalyze biological detoxification, hydrolysis of certain pesticides, and metabolism of many esterified drugs. The development of inhibitors for CE has many potential uses, including increasing drug lifetime and altering biodistrubution; reducing or abrogating toxicity of metabolized drugs; and reducing pest resistance to insecticides. In this review, we discuss the major classes of known mammalian CE inhibitors and describe our computational...

  5. Enhancing Immune Checkpoint Inhibitor Therapy In Kidney Cancer (United States)


    AWARD NUMBER: W81XWH-15-1-0141 TITLE: Enhancing Immune Checkpoint Inhibitor therapy in Kidney Cancer PRINCIPAL INVESTIGATOR: Hans-Joerg Hammers...Immune Checkpoint Inhibitor therapy in Kidney Cancer 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH- 15-1-0141 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR( develop strategies to enhance immune checkpoint inhibition in kidney cancer . The work is designed to test different strategies to induce or

  6. [Regulation of soil nitrification with nitrification inhibitors and related mechanisms]. (United States)

    Sun, Zhi-Mei; Wu, Zhi-Jie; Chen, Li-Jun; Jia, Li-Bin


    To improve the use efficiency of fertilizer N while alleviate its pollution is one of the keys in ensuring the high yield and good quality of agricultural products and the sustainable development of agriculture and environment, for which, applying nitrification inhibitors to retard the course of soil nitrification is an efficient measure. In this review, the definition, screening criteria, major varieties being widely used, and action mechanisms of nitrification inhibitors were introduced, and the existing problems and prospects in related researches were discussed.

  7. Inhibitors of catechol-O-methyltransferase sensitize mice to pain (United States)

    Kambur, O; Talka, R; Ansah, OB; Kontinen, VK; Pertovaara, A; Kalso, E; Männistö, PT


    BACKGROUND AND PURPOSE Catechol-O-methyltransferase (COMT) inhibitors are used in Parkinson's disease in which pain is an important symptom. COMT polymorphisms modulate pain and opioid analgesia in humans. In rats, COMT inhibitors have been shown to be pro-nociceptive in acute pain models, but also to attenuate allodynia and hyperalgesia in a model of diabetic neuropathy. Here, we have assessed the effects of acute and repeated administrations of COMT inhibitors on mechanical, thermal and carrageenan-induced nociception in male mice. EXPERIMENTAL APPROACH We used single and repeated administration of a peripherally restricted, short-acting (nitecapone) and also a centrally acting (3,5-dinitrocatechol, OR-486) COMT inhibitor. We also tested CGP 28014, an indirect inhibitor of COMT enzyme. Effects of OR-486 on thermal nociception were also studied in COMT deficient mice. Effects on spinal pathways were assessed in rats given intrathecal nitecapone. KEY RESULTS After single administration, both nitecapone and OR-486 reduced mechanical nociceptive thresholds and thermal nociceptive latencies (hot plate test) at 2 and 3 h, regardless of their brain penetration. These effects were still present after chronic treatment with COMT inhibitors for 5 days. Intraplantar injection of carrageenan reduced nociceptive latencies and both COMT inhibitors potentiated this reduction without modifying inflammation. CGP 28014 shortened paw flick latencies. OR-486 did not modify hot plate times in Comt gene deficient mice. Intrathecal nitecapone modified neither thermal nor mechanical nociception. CONCLUSIONS AND IMPLICATIONS Pro-nociceptive effects of COMT inhibitors were confirmed. The pro-nociceptive effects were primarily mediated via mechanisms acting outside the brain and spinal cord. COMT protein was required for these actions. PMID:20726980

  8. Structure of a Kunitz-type potato cathepsin D inhibitor

    Czech Academy of Sciences Publication Activity Database

    Guo, J.; Erskine, P. T.; Coker, A. R.; Wood, S. P.; Cooper, J. B.; Mareš, Michael; Baudyš, Miroslav


    Roč. 192, č. 3 (2015), s. 554-560 ISSN 1047-8477 R&D Projects: GA ČR GA15-18929S; GA MŠk LO1302 Institutional support: RVO:61388963 Keywords : potato cathepsin D inhibitor * Kunitz-type protease inhibitor * protein X-ray structure * reactive-site loop * docking Subject RIV: CE - Biochemistry Impact factor: 2.570, year: 2015

  9. Safety of TNF-α inhibitors during IBD pregnancy

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Loftus, Edward V; Jess, Tine


    Tumor necrosis factor (TNF)-alpha inhibitors are increasingly being used in inflammatory bowel disease (IBD). Because this chronic intestinal disorder often affects women of fertile age, it is essential to assess the effect of biologics on pregnancy outcome.......Tumor necrosis factor (TNF)-alpha inhibitors are increasingly being used in inflammatory bowel disease (IBD). Because this chronic intestinal disorder often affects women of fertile age, it is essential to assess the effect of biologics on pregnancy outcome....

  10. Novel targeted therapeutics: inhibitors of MDM2, ALK and PARP

    Directory of Open Access Journals (Sweden)

    Hsueh Chung-Tsen


    Full Text Available Abstract We reviewed preclinical data and clinical development of MDM2 (murine double minute 2, ALK (anaplastic lymphoma kinase and PARP (poly [ADP-ribose] polymerase inhibitors. MDM2 binds to p53, and promotes degradation of p53 through ubiquitin-proteasome degradation. JNJ-26854165 and RO5045337 are 2 small-molecule inhibitors of MDM2 in clinical development. ALK is a transmembrane protein and a member of the insulin receptor tyrosine kinases. EML4-ALK fusion gene is identified in approximately 3-13% of non-small cell lung cancer (NSCLC. Early-phase clinical studies with Crizotinib, an ALK inhibitor, in NSCLC harboring EML4-ALK have demonstrated promising activity with high response rate and prolonged progression-free survival. PARPs are a family of nuclear enzymes that regulates the repair of DNA single-strand breaks through the base excision repair pathway. Randomized phase II study has shown adding PARP-1 inhibitor BSI-201 to cytotoxic chemotherapy improves clinical outcome in patients with triple-negative breast cancer. Olaparib, another oral small-molecule PARP inhibitor, demonstrated encouraging single-agent activity in patients with advanced breast or ovarian cancer. There are 5 other PARP inhibitors currently under active clinical investigation.

  11. Telomerase inhibitors: a patent review (2010-2015). (United States)

    Man, Ruo-Jun; Chen, Long-Wang; Zhu, Hai-Liang


    Telomerase is a ribonucleoprotein that catalyses the addition of telomeric repeat sequences (having the sequence 5'-TTAGGG-3' in humans) to the ends of chromosomes. Telomerase activity is detected in most types of human tumours, but it is almost undetectable in normal somatic cells. Therefore, telomerase is a promising therapeutic target. To date, the known inhibitors of telomerase include nucleoside analogues, oligonucleotides and G-quadruplex stabilizers. This review highlights recent advances in our understanding of telomerase inhibitors, the relationships between telomerase inhibitors, cancer, and fields such as inflammation. This review summarizes new patents published on telomerase inhibitors from 2010 to 2015. The review provides a brief account of the background, development, and on-going issues involving telomerase inhibitors. In particular, this review emphasizes imetelstat (GRN163L) and some typical G-quadruplex stabilizers that participate in telomerase inhibition. Overall, the research scope of antineoplastic is becoming broader and telomerase inhibitors have been shown to be a promising therapeutic target. Therefore, novel antineoplastic agents with greater activity and higher specificity must be developed.

  12. Kinase inhibitors: a new class of antirheumatic drugs

    Directory of Open Access Journals (Sweden)

    Kyttaris VC


    Full Text Available Vasileios C KyttarisDivision of Rheumatology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USAAbstract: The outlook for patients with rheumatoid arthritis has improved significantly over the last three decades with the use of disease-modifying antirheumatic drugs. However, despite the use of methotrexate, cytokine inhibitors, and molecules targeting T and B cells, a percentage of patients do not respond or lose their response over time. The autoimmune process in rheumatoid arthritis depends on activation of immune cells, which utilize intracellular kinases to respond to external stimuli such as cytokines, immune complexes, and antigens. In the past decade, small molecules targeting several kinases, such as p38 MAPK, Syk, and JAK have been developed. Several p38 MAPK inhibitors proved ineffective in treating rheumatoid arthritis. The Syk inhibitor, fostamatinib, proved superior to placebo in Phase II trials and is currently under Phase III investigation. Tofacitinib, a JAK1/3 inhibitor, was shown to be efficacious in two Phase III trials, while VX-509, a JAK3 inhibitor, showed promising results in a Phase II trial. Fostamatinib and tofacitinib were associated with increased rates of infection, elevation of liver enzymes, and neutropenia. Moreover, fostamatinib caused elevations of blood pressure and diarrhea, while tofacitinib was associated with an increase in creatinine and elevation of lipid levels.Keywords: rheumatoid arthritis, kinase inhibitors, mitogen-activated phosphokinase p38, spleen tyrosine kinase, Janus kinases

  13. PKCβ Inhibitors Attenuate Amphetamine-Stimulated Dopamine Efflux. (United States)

    Zestos, Alexander G; Mikelman, Sarah R; Kennedy, Robert T; Gnegy, Margaret E


    Amphetamine abuse afflicts over 13 million people, and there is currently no universally accepted treatment for amphetamine addiction. Amphetamine serves as a substrate for the dopamine transporter and reverses the transporter to cause an increase in extracellular dopamine. Activation of the beta subunit of protein kinase C (PKCβ) enhances extracellular dopamine in the presence of amphetamine by facilitating the reverse transport of dopamine and internalizing the D2 autoreceptor. We previously demonstrated that PKCβ inhibitors block amphetamine-stimulated dopamine efflux in synaptosomes from rat striatum in vitro. In this study, we utilized in vivo microdialysis in live, behaving rats to assess the effect of the PKCβ inhibitors, enzastaurin and ruboxistaurin, on amphetamine-stimulated locomotion and increases in monoamines and their metabolites. A 30 min perfusion of the nucleus accumbens core with 1 μM enzastaurin or 1 μM ruboxistaurin reduced efflux of dopamine and its metabolite 3-methoxytyramine induced by amphetamine by approximately 50%. The inhibitors also significantly reduced amphetamine-stimulated extracellular levels of norepinephrine. The stimulation of locomotor behavior by amphetamine, measured simultaneously with the analytes, was comparably reduced by the PKCβ inhibitors. Using a stable isotope label retrodialysis procedure, we determined that ruboxistaurin had no effect on basal levels of dopamine, norepinephrine, glutamate, or GABA. In addition, normal uptake function through the dopamine transporter was unaltered by the PKCβ inhibitors, as measured in rat synaptosomes. Our results support the utility of using PKCβ inhibitors to reduce the effects of amphetamine.

  14. Sulphonamides as corrosion inhibitor: Experimental and DFT studies (United States)

    Obayes, Hasan R.; Al-Amiery, Ahmed A.; Alwan, Ghadah H.; Abdullah, Thamer Adnan; Kadhum, Abdul Amir H.; Mohamad, Abu Bakar


    Inhibitors are synthetic and natural molecules have various functional groups like double or triple bonds and heteroatoms; N, O or S, which permit adsorption onto the MS (metal surface). These inhibitors have the ability to adsorb onto the MS and block the active site that was reducing the corrosion rate. Inhibition efficiencies of the investigated compounds: Sulfacetamide (SAM), Sulfamerazine (SMR), Sulfapyridine (SPY) and Sulfathiazole (STI), as inhibitors in corrosive solution were evaluated based on weight loss technique. Nitro and Amino groups were chosen for the study of the substituted reaction of four corrosion inhibitor compounds: SAM, SMR, SPY and STI, theoretically utilizing the thickness capacities hypothesis DFT (density functions theory) method with the level [rB3LYP/6-311G(d,p)]. Our research demonstrated that the nitration of studied molecules lead to a diminishing in inhibition efficiencies, group lead to an increase in inhibition efficiency. Compared with corrosion inhibitor molecules these results gave a significant improvement in inhibition efficiency for corrosion inhibitor molecules.

  15. Comparing protein VEGF inhibitors: In vitro biological studies

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Lanlan; Liang, Xiao Huan [Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080 (United States); Ferrara, Napoleone, E-mail: [Genentech, Inc., 1 DNA Way, South San Francisco, CA 94080 (United States)


    Highlights: {yields} VEGF is a mediator of angiogenesis. {yields} VEGF inhibitors have clinical applications in cancer and eye disorders. {yields} Five protein VEGF inhibitors were compared for their ability to inhibit. {yields} VEGF-induced activities in cultured endothelial cells. -- Abstract: VEGF inhibitors are widely used as a therapy for tumors and intravascular neovascular disorders, but limited and conflicting data regarding their relative biological potencies are available. The purpose of the study is to compare different protein VEGF inhibitors for their ability to inhibit VEGF-stimulated activities. We tested ranibizumab, the full-length variant of ranibizumab (Mab Y0317), bevacizumab, the VEGF-TrapR1R2 and Flt(1-3)-IgG in bioassays measuring VEGF-stimulated proliferation of bovine retinal microvascular endothelial cells or chemotaxis of human umbilical vein endothelial cells (HUVEC). The inhibitors were also compared for their ability to inhibit MAP kinase activation in HUVECs following VEGF addition. Ranibizumab, VEGF-TrapR1R2 and Flt(1-3)-IgG had very similar potencies in the bioassays tested. Bevacizumab was over 10-fold less potent than these molecules. Mab Y0317 was over 30-fold more potent than bevacizumab. The findings reported in this manuscript describe important intrinsic characteristics of several VEGF inhibitors that may be useful to design and interpret preclinical or clinical studies.

  16. Quaternary ammonium sulfanilamide: a membrane-impermeant carbonic anhydrase inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Henry, R.P.


    A novel carbonic anhydrase (CA) inhibitor, quaternary ammonium sulfanilamide (QAS), was tested for potency as a CA inhibitor and for its ability to be excluded from permeating biological membranes. Inhibitor titration plots of QAS vs. pure bovine CA II and CA from the gills of the blue crab, Callinectes sapidus, yielded K/sub i/ values of approx. 15; thus QAS is a relatively weak but effective CA inhibitor. Permeability of the QAS was directly tested by two independent methods. The inhibitor was excluded from human erythrocytes incubated in 5 mM QAS for 24 h as determined using an /sup 18/O-labeled mass spectrometer CA assay for intact cells. Also QAS injected into the hemolymph of C. sapidus (1 or 10 mM) did not cross the basal membrane of the gill. The compound was cleared from the hemolymph by 96 h after injection, and at no time during that period could the QAS be detected in homogenates of gill tissue. Total branchial CA activity was only slightly reduced following the QAS injection. These data indicate that QAS is a CA inhibitor to which biological membranes are impermeable and that can be used in vivo and in vitro in the study of membrane-associated CA.

  17. [Anti-amnesic effect of prolyl endopeptidase inhibitors in mice]. (United States)

    Nanri, M; Kaneto, H


    Based on the results of a previous report that prolyl endopeptidase (PPCE) inhibitors facilitated the acquisition of active avoidance response and retarded the extinction of the response, further studies were made on the effect of PPCE inhibitors on learning and the memory process. Using mice, tests were performed both in the light-dark discrimination Y-maze task and the lever-press task of the water reinforcement schedule, and mice were also tested in the acquisition and retention of one-trial "step-through" passive avoidance task. The effect of PPCE inhibitors were investigated both in control and electroconvulsive shock- or scopolamine-induced amnesic animals. Z-Pro-p, the most potent inhibitor among 5 compounds tested in this study, and arginine vasopressin (AVP) facilitated the learning process and retarded the extinction of the acquired response in all tests. Suc-Pro-p was also effective in the Y-maze and passive avoidance test. Thus, the effect of the test compounds were parallel with their in vitro activities as PPCE inhibitor. These results suggest that the anti-amnesic effect of PPCE inhibitors is partially attributable to their effect on the breakdown of the biologically active peptides which are involved in the memory process, such as AVP, in the brain.

  18. FAITH – Fast Assembly Inhibitor Test for HIV

    Energy Technology Data Exchange (ETDEWEB)

    Hadravová, Romana [Institute of Organic Chemistry and Biochemistry IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague (Czech Republic); Rumlová, Michaela, E-mail: [Institute of Organic Chemistry and Biochemistry IOCB Research Centre & Gilead Sciences, Academy of Sciences of the Czech Republic, Flemingovo nám. 2, 166 10 Prague (Czech Republic); Department of Biotechnology, University of Chemistry and Technology, Prague, Technická 5, 166 28 Prague (Czech Republic); Ruml, Tomáš, E-mail: [Department of Biochemistry and Microbiology, University of Chemistry and Technology, Prague, Technická 3, 166 28 Prague (Czech Republic)


    Due to the high number of drug-resistant HIV-1 mutants generated by highly active antiretroviral therapy (HAART), there is continuing demand for new types of inhibitors. Both the assembly of the Gag polyprotein into immature and mature HIV-1 particles are attractive candidates for the blocking of the retroviral life cycle. Currently, no therapeutically-used assembly inhibitor is available. One possible explanation is the lack of a reliable and simple assembly inhibitor screening method. To identify compounds potentially inhibiting the formation of both types of HIV-1 particles, we developed a new fluorescent high-throughput screening assay. This assay is based on the quantification of the assembly efficiency in vitro in a 96-well plate format. The key components of the assay are HIV-1 Gag-derived proteins and a dual-labelled oligonucleotide, which emits fluorescence only when the assembly of retroviral particles is inhibited. The method was validated using three (CAI, BM2, PF74) reported assembly inhibitors. - Highlights: • Allows screening of assembly inhibitors of both mature and immature HIV-1 particles. • Based on Gag-derived proteins with CA in mature or immature conformation. • Simple and sensitive method suitable for high-throughput screening of inhibitors. • Unlike in other HIV assembly methods, works under physiological conditions. • No washing steps are necessary.

  19. Inhibition of matrix metalloproteinase-2 by PARP inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Nicolescu, Adrian C.; Holt, Andrew; Kandasamy, Arulmozhi D. [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada); Pacher, Pal [National Institutes of Health, NIAAA, Laboratory of Physiologic Studies, Bethesda, MD (United States); Schulz, Richard, E-mail: [Departments of Pharmacology and Pediatrics, Cardiovascular Research Centre, University of Alberta, Edmonton, Alta., Canada T6G 2S2 (Canada)


    Matrix metalloproteinase-2 (MMP-2), a ubiquitously expressed zinc-dependent endopeptidase, and poly(ADP-ribosyl) polymerase (PARP), a nuclear enzyme regulating DNA repair, are activated by nitroxidative stress associated with various pathologies. As MMP-2 plays a detrimental role in heart injuries resulting from enhanced nitroxidative stress, where PARP and MMP inhibitors are beneficial, we hypothesized that PARP inhibitors may affect MMP-2 activity. Using substrate degradation assays to determine MMP-2 activity we found that four PARP inhibitors (3-AB, PJ-34, 5-AIQ, and EB-47) inhibited 64 kDa MMP-2 in a concentration-dependent manner. The IC{sub 50} values of PJ-34 and 5-AIQ were in the high micromolar range and comparable to those of known MMP-2 inhibitors doxycycline, minocycline or o-phenanthroline, whereas those for 3-AB and EB-47 were in the millimolar range. Co-incubation of PARP inhibitors with doxycycline showed an additive inhibition of MMP-2 that was significant for 3-AB alone. These data demonstrate that the protective effects of some PARP inhibitors may include inhibition of MMP-2 activity.

  20. [Soluble high molecular weight derivatives of trypsin pancreatic inhibitor. Isolation and properties of dextran-bound pancreatic inhibitor]. (United States)

    Larionova, N I; Kazanskaia, N F; Sakharov, I Iu


    A method of isolating preparations of pancreatic inhibitor of trypsin, bound with soluble polysaccharide carriers, is worked out. It is demonstrated that the reaction of a pancreatic inhibitor and cyanuric chloride-activated dextran proceeds for OH groups of tyrosine residues and for-epsilon-NH2 groups of lysine residues. A method is offered of the protection of amino groups with citraconic anhydride for the complete retaining of the inhibitory activity during attachment to dextran. Thermic denaturation of pancreatic inhibitor preparations at pH 4.7 and 97 degrees C is studied. It is found that the modification by 2-amino-4.6-dichloro-s-triazine stabilizes the protein molecule, while the interaction with the matrix of soluble dextran does not carry any contribution to thermostability of the pancreatic inhibitor.

  1. Oral direct thrombin inhibitors or oral factor Xa inhibitors for the treatment of pulmonary embolism. (United States)

    Robertson, Lindsay; Kesteven, Patrick; McCaslin, James E


    Pulmonary embolism is a potentially life-threatening condition in which a clot can travel from the deep veins, most commonly in the leg, up to the lungs. Previously, a pulmonary embolism was treated with the anticoagulants heparin and vitamin K antagonists. Recently, however, two forms of direct oral anticoagulants (DOACs) have been developed: oral direct thrombin inhibitors (DTI) and oral factor Xa inhibitors. The new drugs have characteristics that may be favourable over conventional treatment, including oral administration, a predictable effect, lack of frequent monitoring or re-dosing and few known drug interactions. To date, no Cochrane review has measured the effectiveness and safety of these drugs in the long-term treatment (minimum duration of three months) of pulmonary embolism. To assess the effectiveness of oral DTIs and oral factor Xa inhibitors for the long-term treatment of pulmonary embolism. The Cochrane Vascular Trials Search Co-ordinator searched the Specialised Register (last searched January 2015) and the Cochrane Register of Studies (last searched January 2015). Clinical trials databases were also searched for details of ongoing or unpublished studies. We searched the reference lists of relevant articles retrieved by electronic searches for additional citations. We included randomised controlled trials in which patients with a pulmonary embolism confirmed by standard imaging techniques were allocated to receive an oral DTI or an oral factor Xa inhibitor for the long-term (minimum duration three months) treatment of pulmonary embolism. Two review authors (LR, JM) independently extracted the data and assessed the risk of bias in the trials. Any disagreements were resolved by discussion with the third author (PK). We used meta-analyses when we considered heterogeneity low. The two primary outcomes were recurrent venous thromboembolism and pulmonary embolism. Other outcomes included all-cause mortality and major bleeding. We calculated all outcomes

  2. Aromatic inhibitors derived from ammonia-pretreated lignocellulose hinder bacterial ethanologenesis by activating regulatory circuits controlling inhibitor efflux and detoxification

    Directory of Open Access Journals (Sweden)

    David H. Keating


    Full Text Available Efficient microbial conversion of lignocellulosic hydrolysates to biofuels is a key barrier to the economically viable deployment of lignocellulosic biofuels. A chief contributor to this barrier is the impact on microbial processes and energy metabolism of lignocellulose-derived inhibitors, including phenolic carboxylates, phenolic amides (for ammonia-pretreated biomass, phenolic aldehydes, and furfurals. To understand the bacterial pathways induced by inhibitors present in ammonia-pretreated biomass hydrolysates, which are less well studied than acid-pretreated biomass hydrolysates, we developed and exploited synthetic mimics of ammonia-pretreated corn stover hydrolysate (ACSH. To determine regulatory responses to the inhibitors normally present in ACSH, we measured transcript and protein levels in an Escherichia coli ethanologen using RNA-seq and quantitative proteomics during fermentation to ethanol of synthetic hydrolysates containing or lacking the inhibitors. Our study identified four major regulators mediating these responses, the MarA/SoxS/Rob network, AaeR, FrmR, and YqhC. Induction of these regulons was correlated with a reduced rate of ethanol production, buildup of pyruvate, depletion of ATP and NAD(PH, and an inhibition of xylose conversion. The aromatic aldehyde inhibitor 5-hydroxymethylfurfural appeared to be reduced to its alcohol form by the ethanologen during fermentation, whereas phenolic acid and amide inhibitors were not metabolized. Together, our findings establish that the major regulatory responses to lignocellulose-derived inhibitors are mediated by transcriptional rather than translational regulators, suggest that energy consumed for inhibitor efflux and detoxification may limit biofuel production, and identify a network of regulators for future synthetic biology efforts.

  3. Dual Use Corrosion Inhibitor and Penetrant for Anomaly Detection in Neutron/X Radiography (United States)

    Hall, Phillip B. (Inventor); Novak, Howard L. (Inventor)


    A dual purpose corrosion inhibitor and penetrant composition sensitive to radiography interrogation is provided. The corrosion inhibitor mitigates or eliminates corrosion on the surface of a substrate upon which the corrosion inhibitor is applied. In addition, the corrosion inhibitor provides for the attenuation of a signal used during radiography interrogation thereby providing for detection of anomalies on the surface of the substrate.

  4. Selection by phage display of a mustard chymotrypsin inhibitor toxic to pea aphid.

    NARCIS (Netherlands)

    Ceci, L.R.; Volpicella, M.; Conti, S.; Gallerani, R.; Beekwilder, M.J.; Jongsma, M.A.


    The mustard trypsin inhibitor, MTI-2, is a potent inhibitor of trypsin with no activity towards chymotrypsin. MTI-2 is toxic for lepidopteran insects, but has low activity against aphids. In an attempt to improve the activity of the inhibitor towards aphids, a library of inhibitor variants was

  5. Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer. (United States)

    Herzberg, Benjamin; Campo, Meghan J; Gainor, Justin F


    Historically, lung cancer was long considered a poorly immunogenic malignancy. In recent years, however, immune checkpoint inhibitors have emerged as promising therapeutic agents in non-small cell lung cancer (NSCLC). To date, the best characterized and most therapeutically relevant immune checkpoints have been cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and the programmed cell death protein-1 (PD-1) pathway. In early studies, PD-1/programmed cell death ligand-1 (PD-L1) inhibitors demonstrated promising antitumor activity and durable clinical responses in a subset of patients. Based on these encouraging results, multiple different PD-1/PD-L1 inhibitors have entered clinical development, and two agents (nivolumab and pembrolizumab) have gained regulatory approval in the United States for the treatment of NSCLC. In several large, randomized studies, PD-1/PD-L1 inhibitors have produced significant improvements in overall survival compared with single-agent docetaxel delivered in the second-line setting, effectively establishing a new standard of care in NSCLC. In the present report, we provide an overview of the rationale for checkpoint inhibitors in lung cancer, recent clinical trial data, and the need for predictive biomarkers. 2017;22:81-88 IMPLICATIONS FOR PRACTICE: Strategies targeting negative regulators (i.e., checkpoints) of the immune system have demonstrated significant antitumor activity across a range of solid tumors. In non-small cell lung cancer (NSCLC), programmed cell death protein-1 (PD-1) pathway inhibitors have entered routine clinical use because of the results from recent randomized studies demonstrating superiority against single-agent chemotherapy in previously treated patients. The present report provides an overview of immune checkpoint inhibitors in lung cancer for the practicing clinician, focusing on the rationale for immunotherapy, recent clinical trial data, and future directions. © AlphaMed Press 2016.

  6. Cellulose Biosynthesis Inhibitors: Comparative Effect on Bean Cell Cultures

    Directory of Open Access Journals (Sweden)

    José L. Acebes


    Full Text Available The variety of bioassays developed to evaluate different inhibition responses for cellulose biosynthesis inhibitors makes it difficult to compare the results obtained. This work aims (i to test a single inhibitory assay for comparing active concentrations of a set of putative cellulose biosynthesis inhibitors and (ii to characterize their effect on cell wall polysaccharides biosynthesis following a short-term exposure. For the first aim, dose-response curves for inhibition of dry-weight increase following a 30 days exposure of bean callus-cultured cells to these inhibitors were obtained. The compound concentration capable of inhibiting dry weight increase by 50% compared to control (I50 ranged from subnanomolar (CGA 325′615 to nanomolar (AE F150944, flupoxam, triazofenamide and oxaziclomefone and micromolar (dichlobenil, quinclorac and compound 1 concentrations. In order to gain a better understanding of the effect of the putative inhibitors on cell wall polysaccharides biosynthesis, the [14C]glucose incorporation into cell wall fractions was determined after a 20 h exposure of cell suspensions to each inhibitor at their I50 value. All the inhibitors tested decreased glucose incorporation into cellulose with the exception of quinclorac, which increased it. In some herbicide treatments, reduction in the incorporation into cellulose was accompanied by an increase in the incorporation into other fractions. In order to appreciate the effect of the inhibitors on cell wall partitioning, a cluster and Principal Component Analysis (PCA based on the relative contribution of [14C]glucose incorporation into the different cell wall fractions were performed, and three groups of compounds were identified. The first group included quinclorac, which increased glucose incorporation into cellulose; the second group consisted of compound 1, CGA 325′615, oxaziclomefone and AE F150944, which decreased the relative glucose incorporation into cellulose but

  7. Inhibition of tracheal smooth muscle cell proliferation by phosphodiesterase inhibitors

    Directory of Open Access Journals (Sweden)

    Kazuko Masu


    Full Text Available Agents that increase intracellular cyclic 3',5'-adenosine monophosphate (cAMP, such as forskolin, prostaglandin (PGE2, salbutamol and 8-bromo-cAMP, have been shownto inhibit the proliferation of airway smooth-muscle (ASM cells in vitro. However, it has not yet been determined whether selective inhibitors of phosphodiesterase (PDE isoenzymes III and IV that catalyze cAMPto 5'-adenosine monophosphate have the ability to inhibit ASM cell proliferation. To evaluate the effectsof PDE inhibitors on ASM cell proliferation, ASM cells isolated from bovine tracheae were cultured in the presence of fetal bovine serum (FBS, with or without a non-selective PDE inhibitor (theophylline, a selective PDE III inhibitor (cilostazol, and a selective PDE IV inhibitor (rolipram. The number of ASM cells cultured with 5% FBS was significantly reduced by the presence of theophylline at 10−3 and 3 × 10−4 mol/L, cilostazol at 10−5, 10−6 and 10−7 mol/L, and rolipram at 10−4 and 10−5 mol/L. The release of lactic dehydrogenase from ASM cells cultured with any concentration of these agents was not significantly different from that with medium alone. Inhibitors of PDE III and IV were demonstrated to have an inhibitory effect on ASM cell proliferation induced by FBS. Our results suggest the value of the further development of PDE inhibitors for the treatment of hyperplasia of ASM cells characteristic of airway remodeling, in addition to bronchospasm and airway inflammation, in bronchial asthma.

  8. Effect of the scale inhibitor on ion content in reverse osmosis system for seawater desalination (United States)

    Gao, Yuhua; Liu, Zhenfa; Zhang, Lihui; Li, Haihua


    A scale inhibitor was synthesized from polysuccinimide with 2-aminoethanesulfonic acid and aspartic acid. The effect of scale inhibitor on ion content in reverse osmosis system for seawater desalination was studied. The results showed that the ion content of permeate water is lower with the scale inhibitor added in RO system for seawater desalination than without scale inhibitor. On the contrary, the ion content of concentrate water is higher when with scale inhibitor in RO system.

  9. Localization to Chromosomes of Structural Genes for the Major Protease Inhibitors of Barley Grains

    DEFF Research Database (Denmark)

    Hejgaard, Jørn; Bjørn, S.E.; Nielsen, Gunnar Gissel


    Wheat-barley chromosome addition lines were compared by isoelectric focusing of protein extracts to identify chromosomes carrying loci for the major immunochemically distinct protease inhibitors of barley grains. Structural genes for the following inhibitors were localized: an inhibitor of both...... endogenous α-amylase 2 and subtilisin (ASI) on chromosome 2, two chymotrypsin/subtilisin inhibitors (CI-1 and CI-2) on chromosome 5 (long arm) and the major trypsin inhibitor (TI-1) on chromosome 3....

  10. Bone mineral density changes in protease inhibitor-sparing vs. nucleoside reverse transcriptase inhibitor-sparing highly active antiretroviral therapy: data from a randomized trial

    DEFF Research Database (Denmark)

    Hansen, Ann-Brit Eg; Obel, N; Nielsen, H


    The aim of the study was to compare changes in bone mineral density (BMD) over 144 weeks in HIV-infected patients initiating nucleoside reverse transcriptase inhibitor (NRTI)-sparing or protease inhibitor-sparing highly active antiretroviral therapy (HAART).......The aim of the study was to compare changes in bone mineral density (BMD) over 144 weeks in HIV-infected patients initiating nucleoside reverse transcriptase inhibitor (NRTI)-sparing or protease inhibitor-sparing highly active antiretroviral therapy (HAART)....

  11. Insights into the binding mode of MEK type-III inhibitors. A step towards discovering and designing allosteric kinase inhibitors across the human kinome


    Zhao, Zheng; Xie, Lei; Bourne, Philip E.


    Protein kinases are critical drug targets for treating a large variety of human diseases. Type-III kinase inhibitors have attracted increasing attention as highly selective therapeutics. Thus, understanding the binding mechanism of existing type-III kinase inhibitors provides useful insights into designing new type-III kinase inhibitors. In this work, we have systematically studied the binding mode of MEK-targeted type-III inhibitors using structural systems pharmacology and molecular dynamic...

  12. Structure-Based Discovery of Inhibitors of Thymidylate Synthase (United States)

    Shoichet, Brian K.; Stroud, Robert M.; Santi, Daniel V.; Kuntz, Irwin D.; Perry, Kathy M.


    A molecular docking computer program (DOCK) was used to screen the Fine Chemical Directory, a database of commercially available compounds, for molecules that are complementary to thymidylate synthase (TS), a chemotherapeutic target. Besides retrieving the substrate and several known inhibitors, DOCK proposed putative inhibitors previously unknown to bind to the enzyme. Three of these compounds inhibited Lactobacillus caser TS at submillimolar concentrations. One of these inhibitors, sulisobenzone, crystallized with TS in two configurations that differed from the DOCK-favored geometry: a counterion was bound in the substrate site, which resulted in a 6 to 9 angstrom displacement of the inhibitor. The structure of the complexes suggested another binding region in the active site that could be exploited. This region was probed with molecules sterically similar to sulisobenzone, which led to the identification of a family of phenolphthalein analogs that inhibit TS in the 1 to 30 micromolar range. These inhibitors do not resemble the substrates of the enzyme. A crystal structure of phenolphthalein with TS shows that it binds in the target site in a configuration that resembles the one suggested by DOCK.

  13. Allele diversity for the apoplastic invertase inhibitor gene from potato. (United States)

    Datir, Sagar S; Latimer, Julie M; Thomson, Susan J; Ridgway, Hayley J; Conner, Anthony J; Jacobs, Jeanne M E


    In planta the enzymatic activity of apoplastic and vacuolar invertases is controlled by inhibitory proteins. Although these invertase inhibitors (apoplastic and vacuolar forms) have been implicated as contributing to resistance to cold-induced sweetening (CIS) in tubers of potato (Solanum tuberosum L.), there is a lack of information on the structure and allelic diversity of the apoplastic invertase inhibitor genes. We have PCR-isolated and sequenced the alleles of the apoplastic invertase inhibitor gene (Stinh1) from three tetraploid potato genotypes: 1021/1 (a genotype with very high tolerance to CIS), 'Karaka' and 'Summer Delight' (two cultivars that are highly susceptible to CIS). In total, five alleles were identified in these genotypes, of which four (Stinh1-c, Stinh1-d, Stinh1-e, Stinh1-f) were novel. An analysis of allele diversity was conducted by incorporating previously published sequences of apoplastic invertase inhibitors from potato. Eight alleles were assessed for sequence polymorphism in the two exons and the single hypervariable intron. Contrary to the hypervariable intron, only 65 single nucleotide polymorphisms were observed in the exons, of which 42 confer amino acid substitutions. Phylogenetic analysis of amino acid sequences indicates that the alleles of the invertase inhibitor are highly conserved amongst members of the Solanaceae family.

  14. Renal Effects of DPP-4 Inhibitors: A Focus on Microalbuminuria

    Directory of Open Access Journals (Sweden)

    Martin Haluzík


    Full Text Available Incretin-based therapies represent one of the most promising options in type 2 diabetes treatment owing to their good effectiveness with low risk of hypoglycemia and no weight gain. Other numerous potential beneficial effects of incretin-based therapies have been suggested based mostly on experimental and small clinical studies including its beta-cell- and vasculo-protective actions. One of the recently emerged interesting features of dipeptidyl peptidase-4 (DPP-4 inhibitors is its possible protective effect on the diabetic kidney disease. Here, we review the renal effects of DPP-4 inhibitors with special focus on its influence on the onset and progression of microalbuminuria, as presence of microalbuminuria represents an important early sign of kidney damage and is also associated with increased risk of hypoglycemia and cardiovascular complications. Mechanisms underlying possible nephroprotective properties of DPP-4 inhibitors include reduction of oxidative stress and inflammation and improvement of endothelial dysfunction. Effects of DPP-4 inhibitors may be both glucagon-like peptide-1 (GLP-1 dependent and independent. Ongoing prospective studies focused on the nephroprotective effects of DPP-4 inhibitors will further clarify its possible role in the prevention/attenuation of diabetic kidney disease beyond its glucose lowering properties.

  15. Elastase inhibitors as potential therapies for ELANE-associated neutropenia. (United States)

    Makaryan, Vahagn; Kelley, Merideth L; Fletcher, Breanna; Bolyard, Audrey Anna; Aprikyan, A Andrew; Dale, David C


    Mutations in ELANE, the gene for neutrophil elastase (NE), a protease expressed early in neutrophil development, are the most frequent cause of cyclic (CyN) and severe congenital neutropenia (SCN). We hypothesized that inhibitors of NE, acting either by directly inhibiting enzymatic activity or as chaperones for the mutant protein, might be effective as therapy for CyN and SCN. We investigated β-lactam-based inhibitors of human NE (Merck Research Laboratories, Kenilworth, NJ, USA), focusing on 1 inhibitor called MK0339, a potent, orally absorbed agent that had been tested in clinical trials and shown to have a favorable safety profile. Because fresh, primary bone marrow cells are rarely available in sufficient quantities for research studies, we used 3 cellular models: patient-derived, induced pluripotent stem cells (iPSCs); HL60 cells transiently expressing mutant NE; and HL60 cells with regulated expression of the mutant enzyme. In all 3 models, the cells expressing the mutant enzyme had reduced survival as measured with annexin V and FACS. Coincubation with the inhibitors, particularly MK0339, promoted cell survival and increased formation of mature neutrophils. These studies suggest that cell-permeable inhibitors of neutrophil elastase show promise as novel therapies for ELANE-associated neutropenia. © Society for Leukocyte Biology.

  16. Carba-cyclophellitols Are Neutral Retaining-Glucosidase Inhibitors. (United States)

    Beenakker, Thomas J M; Wander, Dennis P A; Offen, Wendy A; Artola, Marta; Raich, Lluís; Ferraz, Maria J; Li, Kah-Yee; Houben, Judith H P M; van Rijssel, Erwin R; Hansen, Thomas; van der Marel, Gijsbert A; Codée, Jeroen D C; Aerts, Johannes M F G; Rovira, Carme; Davies, Gideon J; Overkleeft, Herman S


    The conformational analysis of glycosidases affords a route to their specific inhibition through transition-state mimicry. Inspired by the rapid reaction rates of cyclophellitol and cyclophellitol aziridine-both covalent retaining β-glucosidase inhibitors-we postulated that the corresponding carba "cyclopropyl" analogue would be a potent retaining β-glucosidase inhibitor for those enzymes reacting through the 4H3 transition-state conformation. Ab initio metadynamics simulations of the conformational free energy landscape for the cyclopropyl inhibitors show a strong bias for the 4H3 conformation, and carba-cyclophellitol, with an N-(4-azidobutyl)carboxamide moiety, proved to be a potent inhibitor (Ki = 8.2 nM) of the Thermotoga maritima TmGH1 β-glucosidase. 3-D structural analysis and comparison with unreacted epoxides show that this compound indeed binds in the 4H3 conformation, suggesting that conformational strain induced through a cyclopropyl unit may add to the armory of tight-binding inhibitor designs.

  17. [Pharmacogenic osteoporosis beyond cortisone. Proton pump inhibitors, glitazones and diuretics]. (United States)

    Kann, P H; Hadji, P; Bergmann, R S


    [corrected] There are many drugs which can cause osteoporosis or at least favor its initiation. The effect of hormones and drugs with antihormonal activity, such as glucocorticoids and aromatase inhibitors, on initiation of osteoporosis is well known. In addition, proton pump inhibitors, glitazones and diuretics also influence the formation of osteoporosis. The results of currently available studies on the correlation between proton pump inhibitors, glitazones and diuretics on formation of osteoporosis were evaluated and summarized. Proton pump inhibitors and glitazones increase the risk for osteoporotic fractures. Loop diuretics may slightly increase fracture risk, whereas thiazides were shown to be osteoprotective by reducing fracture probability on a relevant scale. Proton pump inhibitors should not be prescribed without serious consideration and then only as long as necessary. Alternatively, the administration of the less effective H2 antagonists should be considered when possible due to the reduction of acid secretion. Because the long-term intake of thiazides is associated with a clinically relevant reduction in the risk of fractures and they are economic and well-tolerated, prescription can be thoroughly recommended within the framework of differential diagnostic considerations in an appropriate clinical context. The briefly increased risk of falling immediately after starting diuretic therapy is the only point which needs to be considered.

  18. Development of organometallic S6K1 inhibitors. (United States)

    Qin, Jie; Rajaratnam, Rajathees; Feng, Li; Salami, Jemilat; Barber-Rotenberg, Julie S; Domsic, John; Reyes-Uribe, Patricia; Liu, Haiying; Dang, Weiwei; Berger, Shelley L; Villanueva, Jessie; Meggers, Eric; Marmorstein, Ronen


    Aberrant activation of S6 kinase 1 (S6K1) is found in many diseases, including diabetes, aging, and cancer. We developed ATP competitive organometallic kinase inhibitors, EM5 and FL772, which are inspired by the structure of the pan-kinase inhibitor staurosporine, to specifically inhibit S6K1 using a strategy previously used to target other kinases. Biochemical data demonstrate that EM5 and FL772 inhibit the kinase with IC50 value in the low nanomolar range at 100 μM ATP and that the more potent FL772 compound has a greater than 100-fold specificity over S6K2. The crystal structures of S6K1 bound to staurosporine, EM5, and FL772 reveal that the EM5 and FL772 inhibitors bind in the ATP binding pocket and make S6K1-specific contacts, resulting in changes to the p-loop, αC helix, and αD helix when compared to the staurosporine-bound structure. Cellular data reveal that FL772 is able to inhibit S6K phosphorylation in yeast cells. Together, these studies demonstrate that potent, selective, and cell permeable S6K1 inhibitors can be prepared and provide a scaffold for future development of S6K inhibitors with possible therapeutic applications.

  19. Cobalt (III) complexes as novel matrix metalloproteinase-9 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jiyoun [Sungshin Women' s Univ., Seoul (Korea, Republic of)


    We have synthesized a series of novel MMP-9 inhibitors containing cobalt(III) complexes. The synthesized cobalt(III) complexes are effective as enzyme inhibitors and the attachment of a biphenyl group enhanced the efficiency of enzyme inhibition up to 6-fold. When compared to the reported non-hydroxamate MMP inhibitors, the synthesized complexes showed comparable in vitro potency. The enzyme assay showed that the cobalt(III) complex can disrupt the zinc binding active site of MMP-9 and is proposed to work via a ligand exchange mechanism. Since histidine residues are essential for the catalytic activity of a large percentage of enzymes and zinc finger proteins, these cobalt(III) complexes can serve as a prototype inhibitor towards various zinc containing enzymes and proteins. Matrix metalloproteinases (MMPs) are a family of zinc binding endopeptidases that play crucial roles in various physiological processes and diseases such as embryogenic growth, angiogenesis, arthritis, skin ulceration, liver fibrosis and tumor metastasis. Because of their implications in a wide range of diseases, MMPs are considered as intriguing drug targets. The majority of MMP inhibitors are organic small molecules containing a hydroxamate functionality for the zinc binding group. This hydroxamate group binds to a zinc(II) center in a bidentate fashion and creates a distorted trigonal bipyramidal geometry.

  20. Allosteric Small-Molecule Inhibitors of the AKT Kinase (United States)

    Dalafave, D. S.

    This research addresses computational design of small druglike molecules for possible anticancer applications. AKT and SGK are kinases that control important cellular functions. They are highly homologous, having similar activators and targets. Cancers with increased SGK activity may develop resistance to AKT-specific inhibitors. Our goal was to design new molecules that would bind both AKT and SGK, thus preventing the development of drug resistance. Most kinase inhibitors target the kinase ATP-binding site. However, the high similarity in this site among kinases makes it difficult to target specifically. Furthermore, mutations in this site can cause resistance to ATP-competitive kinase inhibitors. We used existing AKT inhibitors as initial templates to design molecules that could potentially bind the allosteric sites of both AKT and SGK. Molecules with no implicit toxicities and optimal drug-like properties were used for docking studies. Binding energies of the stable complexes that the designed molecules formed with AKT and SGK were calculated. Possible applications of the designed putative inhibitors against cancers with overexpressed AKT/SGK is discussed.

  1. Immune Checkpoint Inhibitors in Lung Cancer: Imaging Considerations. (United States)

    Wang, Gary X; Guo, Lan Qian; Gainor, Justin F; Fintelmann, Florian J


    The purpose of this article is to review the mechanisms of action of immune checkpoint inhibitors in the treatment of non-small cell lung cancer (NSCLC), highlight imaging manifestations of common adverse events, and discuss new criteria for using imaging to assess unique treatment response patterns. Immune checkpoint inhibitor therapy is a breakthrough in cancer treatment that has shown unprecedented success when used for a variety of malignancies. In recent phase 3 clinical trials for NSCLC, monoclonal antibodies that target the programmed death-1 (PD-1) receptor and its ligand PD-L1 (i.e., the PD-1/PD-L1 axis) were associated with better overall survival in head-to-head comparisons with conventional cytotoxic chemotherapy. On the strength of the results of these trials, the PD-1 inhibitors nivolumab and pembrolizumab and the PD-L1 inhibitor atezolizumab recently received regulatory approval by the U.S. Food and Drug Administration for the treatment of advanced NSCLC. Because of their unique mechanisms of action, these agents differ from conventional cytotoxic chemotherapy in both patterns of treatment response and treatment-related adverse events. Given the rapidly expanding clinical use of immune checkpoint inhibitors and the central role of radiology in the care of patients with lung cancer, it is important for radiologists to be familiar with these agents and their unique imaging findings.

  2. The Nonglycemic Actions of Dipeptidyl Peptidase-4 Inhibitors

    Directory of Open Access Journals (Sweden)

    Na-Hyung Kim


    Full Text Available A cell surface serine protease, dipeptidyl peptidase 4 (DPP-4, cleaves dipeptide from peptides containing proline or alanine in the N-terminal penultimate position. Two important incretin hormones, glucagon-like peptide-1 (GLP-1 and glucose-dependent insulinotropic peptide (GIP, enhance meal-stimulated insulin secretion from pancreatic β-cells, but are inactivated by DPP-4. Diabetes and hyperglycemia increase the DPP-4 protein level and enzymatic activity in blood and tissues. In addition, multiple other functions of DPP-4 suggest that DPP-4 inhibitor, a new class of antidiabetic agents, may have pleiotropic effects. Studies have shown that DPP-4 itself is involved in the inflammatory signaling pathway, the stimulation of vascular smooth cell proliferation, and the stimulation of oxidative stress in various cells. DPP-4 inhibitor ameliorates these pathophysiologic processes and has been shown to have cardiovascular protective effects in both in vitro and in vivo experiments. However, in recent randomized clinical trials, DPP-4 inhibitor therapy in high risk patients with type 2 diabetes did not show cardiovascular protective effects. Some concerns on the actions of DPP-4 inhibitor include sympathetic activation and neuropeptide Y-mediated vascular responses. Further studies are required to fully characterize the cardiovascular effects of DPP-4 inhibitor.

  3. Discovery and development of heat shock protein 90 inhibitors. (United States)

    Taldone, Tony; Sun, Weilin; Chiosis, Gabriela


    Heat shock protein 90 (Hsp90) is an important target in cancer because of its role in maintaining transformation and has recently become the focus of several drug discovery and development efforts. While compounds with different modes of action are known, the focus of this review is on those classes of compounds which inhibit Hsp90 by binding to the N-terminal ATP pocket. These include natural product inhibitors such as geldanamycin and radicicol and synthetic inhibitors comprised of purines, pyrazoles, isoxazoles and other scaffolds. The synthetic inhibitors have been discovered either by structure-based design, high throughput screening and more recently using fragment-based design and virtual screening techniques. This review will discuss the discovery of these different classes, as well as their development as potential clinical agents.

  4. Microorganisms as potential corrosion inhibitors of metallic materials

    Directory of Open Access Journals (Sweden)

    Tasić Žaklina Z.


    Full Text Available Corrosion presents the destruction of materials through chemical or electrochemical interactions with their environment. Interactions between the metal surface and bacterial cells or products of their metabolic activities can lead to microbially-influenced corrosion. Also, it is known that certain microorganisms can contribute to corrosion inhibition. In accordance to that, the literature dealing with the application of different microorganisms as a potentialy corrosion inhibitors of metals is investigated. Different bacterial strains as a corrosion inhibitor of a metalic materials are examined. Further, the role of extracellular polymeric substances in corrosion behavior of metals is emphasized. Based on the data presented in this work, it can be said that inhibition efficiency depends on microorganism as well as type of metal. Also, it is presented that some bacterial species can be used as a good corrosion inhibitor instead of toxic organic compounds.

  5. Skin whitening agents: medicinal chemistry perspective of tyrosinase inhibitors. (United States)

    Pillaiyar, Thanigaimalai; Manickam, Manoj; Namasivayam, Vigneshwaran


    Melanogenesis is a process to synthesize melanin, which is a primary responsible for the pigmentation of human skin, eye and hair. Although numerous enzymatic catalyzed and chemical reactions are involved in melanogenesis process, the enzymes such as tyrosinase and tyrosinase-related protein-1 (TRP-1) and TRP-2 played a major role in melanin synthesis. Specifically, tyrosinase is a key enzyme, which catalyzes a rate-limiting step of the melanin synthesis, and the downregulation of tyrosinase is the most prominent approach for the development of melanogenesis inhibitors. Therefore, numerous inhibitors that target tyrosinase have been developed in recent years. The review focuses on the recent discovery of tyrosinase inhibitors that are directly involved in the inhibition of tyrosinase catalytic activity and functionality from all sources, including laboratory synthetic methods, natural products, virtual screening and structure-based molecular docking studies.

  6. Clinical development of phosphatidylinositol-3 kinase pathway inhibitors. (United States)

    Arteaga, Carlos L


    The PI3K pathway is the most commonly altered in human cancer. Several recent phase I studies with therapeutic inhibitors of this pathway have shown that pharmacological inhibition of PI3K in humans is feasible and overall well tolerated. Furthermore, there has already been clinical evidence of anti-tumor activity in patients with advanced cancer. The intensity and duration of PI3K inhibition required for an antitumor effect and the optimal pharmacodynamic biomarker(s) of pathway inactivation remain to be established. Preclinical and early clinical data support focusing on trials with PI3K inhibitors that are at a minimum enriched with patients with alterations in this signaling pathway. These inhibitors are likely to be more effective in combination with established and other novel molecular therapies.

  7. Therapeutic utility of Phosphodiesterase type I inhibitors in neurological conditions.

    Directory of Open Access Journals (Sweden)

    Alexandre Esteves Medina


    Full Text Available Neuronal plasticity is an essential property of the brain that is impaired in different neurological conditions. Phosphodiesterase type 1 (PDE1 inhibitors can enhance levels of the second messengers cAMP/cGMP leading to the expression of neuronal plasticity-related genes, neurotrophic factors and neuroprotective molecules. These neuronal plasticity enhancement properties make PDE1 inhibitors good candidates as therapeutic agents in many neurological conditions. However, the lack of specificity of the drugs currently available poses a challenge to the systematic evaluation of the beneficial effect of these agents. The development of more specific drugs may pave the way for the use of PDE1 inhibitors as therapeutic agents in cases of neurodevelopmental conditions such as fetal alcohol spectrum disorders and in degenerative disorders such as Alzheimer’s and Parkinson’s.

  8. Difluoromethane, a new and improved inhibitor of methanotrophy (United States)

    Miller, L.G.; Sasson, C.; Oremland, R.S.


    Difluoromethane (HFC-32; DFM) is compared to acetylene and methyl fluoride as an inhibitor of methanotrophy in cultures and soils. DFM was found to be a reversible inhibitor of CH4 oxidation by Methylococcus capsulatus (Bath). Consumption of CH4 in soil was blocked by additions of low levels of DFM (0.03 kPa), and this inhibition was reversed by DFM removal. Although a small quantity of DFM was consumed during these incubations, its remaining concentration was sufficiently elevated to sustain inhibition. Methanogenesis in anaerobic soil slurries, including acetoclastic methanogenesis, was unaffected by levels of DFM which inhibit methanotrophy. Low levels of DFM (0.03 kPa) also inhibited nitrification and N2O production by soils. DFM is proposed as an improved inhibitor of CH4 oxidation over acetylene and/or methyl fluoride on the basis of its reversibility, its efficacy at low concentrations, its lack of inhibition of methanogenesis, and its low cost.


    Directory of Open Access Journals (Sweden)

    M. P. Metrova


    Full Text Available Aim. To study effects of ACE inhibitor perindopril on markers of endothelial dysfunction in therapy of patients with arterial hypertension (HT.Material and methods. 82 patients with HT, complicated by ischemic stroke were involved in the study. 30 patients with uncomplicated HT were included into control group. Antihypertensive therapy with perindopril (52 patients or amlodipine (30 patients was conducted additionally to standard neurotropic therapy in hypertensive patients with ischemic stroke. Phase-contrast microscopy and enzyme immunoassay were used for screening of endothelial dysfunction markers (blebbing, desquamated endothelial cells, membrane-liberated parts, sPECAM-1.Results. Reduction in levels of markers of endothelial dysfunction was observed among patients treated with perindopril in comparison with patients who did not receive ACE inhibitor or patients of control group. Target levels of blood pressure were reached in 96% of patients treated with perindopril. Сonclusion. ACE inhibitors in therapy patients with HT reduce endothelial dysfunction additionally to antihypertensive effect.

  10. Heteroarylimino-4-thiazolidinones as inhibitors of cartilage degradation. (United States)

    Panico, Anna Maria; Vicini, Paola; Geronikaki, Athina; Incerti, Matteo; Cardile, Venera; Crascì, Lucia; Messina, Rossella; Ronsisvalle, Simone


    2-Benzo[d]thiazolyl- and 2-benzo[d]isothiazolyl-imino-5-benzylidene-4-thiazolidinone derivatives were investigated as potential metalloproteinases (MMPs) inhibitors and evaluated for their antidegenerative activity on human chondrocyte cultures stimulated by IL-1β, using an experimental model that reproduces the mechanisms involved in osteoarthritic (OA) diseases. Cell viability, the amount of glycosaminoglycans (GAGs) and the production of nitric oxide (NO) were measured. The most potent compound, 5-(4-methoxy-benzylidene)-2-(benzo[d]isothiazol-3-ylimino)-thiazolidin-4-one (4b), a MMP-13 inhibitor at nanomolar concentration (IC(50)=0.036 μM), could be considered as a lead compound for the development of novel clinical agents, inhibitors of cartilage degradation, for the treatment of OA. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. New directions for protease inhibitors directed drug discovery. (United States)

    Hamada, Yoshio; Kiso, Yoshiaki


    Proteases play crucial roles in various biological processes, and their activities are essential for all living organisms-from viruses to humans. Since their functions are closely associated with many pathogenic mechanisms, their inhibitors or activators are important molecular targets for developing treatments for various diseases. Here, we describe drugs/drug candidates that target proteases, such as malarial plasmepsins, β-secretase, virus proteases, and dipeptidyl peptidase-4. Previously, we reported inhibitors of aspartic proteases, such as renin, human immunodeficiency virus type 1 protease, human T-lymphotropic virus type I protease, plasmepsins, and β-secretase, as drug candidates for hypertension, adult T-cell leukaemia, human T-lymphotropic virus type I-associated myelopathy, malaria, and Alzheimer's disease. Our inhibitors are also described in this review article as examples of drugs that target proteases. © 2015 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 106: 563-579, 2016. © 2015 Wiley Periodicals, Inc.

  12. Chemical structure and properties of low-molecular furin inhibitors

    Directory of Open Access Journals (Sweden)

    T. V. Osadchuk


    Full Text Available The review is devoted to the analysis of the relationship between a chemical structure and properties of low-molecular weight inhibitors of furin, the most studied proprotein convertase, which is involved in the development of some pathologies, such as oncologic diseases, viral and bacterial infections, etc. The latest data concerning the influence of peptides, pseudo-peptides, aromatic and heterocyclic compounds, some natural ones such as flavonoids, coumarins, and others on enzyme inactivation are considered. The power of furin inhibition is shown to rise with the increasing number of positively charged groups in the structure of these compounds. Peptidomimetics (Ki = 5-8 pM are shown to be the most effective furin inhibitors. The synthesized substances, however, have not been used in practical application yet. Nowadays it is very important to find more selective inhibitors, improve their stability, bioavailability and safety for the human organism.

  13. Prolonged and tunable residence time using reversible covalent kinase inhibitors (United States)

    Bradshaw, J. Michael; McFarland, Jesse M.; Paavilainen, Ville O.; Bisconte, Angelina; Tam, Danny; Phan, Vernon T.; Romanov, Sergei; Finkle, David; Shu, Jin; Patel, Vaishali; Ton, Tony; Li, Xiaoyan; Loughhead, David G.; Nunn, Philip A.; Karr, Dane E.; Gerritsen, Mary E.; Funk, Jens Oliver; Owens, Timothy D.; Verner, Erik; Brameld, Ken A.; Hill, Ronald J.; Goldstein, David M.; Taunton, Jack


    Drugs with prolonged, on-target residence time often show superior efficacy, yet general strategies for optimizing drug-target residence time are lacking. Here, we demonstrate progress toward this elusive goal by targeting a noncatalytic cysteine in Bruton's tyrosine kinase (BTK) with reversible covalent inhibitors. Utilizing an inverted orientation of the cysteine-reactive cyanoacrylamide electrophile, we identified potent and selective BTK inhibitors that demonstrate biochemical residence times spanning from minutes to 7 days. An inverted cyanoacrylamide with prolonged residence time in vivo remained bound to BTK more than 18 hours after clearance from the circulation. The inverted cyanoacrylamide strategy was further utilized to discover fibroblast growth factor receptor (FGFR) kinase inhibitors with residence times of several days, demonstrating generalizability of the approach. Targeting noncatalytic cysteines with inverted cyanoacrylamides may serve as a broadly applicable platform that facilitates “residence time by design”, the ability to modulate and improve the duration of target engagement in vivo. PMID:26006010

  14. Seizure following the Use of the COX-2 Inhibitor Etoricoxib

    Directory of Open Access Journals (Sweden)

    Valentina Arnao


    Full Text Available We describe a case of epileptic seizures occurring after the use of a COX-2 inhibitor. A 61-year-old man was admitted to our department because of a generalized tonic-clonic seizure. EEG showed generalized slowdown of the activity. Neuroimaging and blood samples studies did not evidence alterations, but a careful pharmacological history revealed that the patient had taken the COX-2 inhibitor etoricoxib to treat lumbago few days before the onset of clinical symptoms. No seizures were reported after etoricoxib discontinuation and an EEG resulted to be normal two months after this. Conclusion. Knowing the pharmacological history of a patient is important for understanding the clinical presentation and selecting appropriate treatment. This is, to the best of our knowledge, the first reported case of generalized seizures associated with the use of COX-2 inhibitors.

  15. 6beta,19-Bridged androstenedione analogs as aromatase inhibitors. (United States)

    Komatsu, Sachiko; Yaguchi, Ayaka; Yamashita, Kouwa; Nagaoka, Masao; Numazawa, Mitsuteru


    Inhibition of aromatase is an efficient approach for the prevention and treatment of breast cancer. New 6beta,19-bridged steroid analogs of androstenedione, 6beta,19-epithio- and 6beta,19-methano compounds 11 and 17, were synthesized starting from 19-hydroxyandrostenedione (6) and 19-formylandrost-5-ene-3beta,17beta-yl diacetate (12), respectively, as aromatase inhibitors. All of the compounds including known steroids 6beta,19-epoxyandrostenedione (4) and 6beta,19-cycloandrostenedione (5) tested were weak to poor competitive inhibitors of aromatase and, among them, 6beta,19-epoxy steroid 4 provided only moderate inhibition (K(i): 2.2 microM). These results show that the 6beta,19-bridged groups of the inhibitors interfere with binding in active site of aromatase.

  16. Heterocyclic inhibitors of AChE acylation and peripheral sites. (United States)

    Bolognesi, Maria Laura; Andrisano, Vincenza; Bartolini, Manuela; Cavalli, Andrea; Minarini, Anna; Recanatini, Maurizio; Rosini, Michela; Tumiatti, Vincenzo; Melchiorre, Carlo


    Notwithstanding the criticism to the so called " cholinergic hypothesis", the therapeutic strategies for the treatment of Alzheimer's disease (AD) have been mainly centered on the restoration of cholinergic functionality and, until the last year, the only drugs licensed for the management of AD were the acetycholinesterase (AChE) inhibitors. Target enzyme AChE consists of a narrow gorge with two separate ligand binding sites: an acylation site at the bottom of the gorge containing the catalytic triad and a peripheral site located at the gorge rim, which encompasses binding sites for allosteric ligands. The aim of this short review is to update the knowledge on heterocyclic AChE inhibitors able to interact with the two sites of enzymes, structurally related to the well known inhibitors physostigmine, rivastigmine and propidium. The therapeutic potential of the dual site inhibithors in inhibiting amyloid-beta aggregatrion and deposition is also briefly summarised.

  17. MEK Inhibitors Reverse cAMP-Mediated Anxiety in Zebrafish

    DEFF Research Database (Denmark)

    Lundegaard, Pia R.; Anastasaki, Corina; Grant, Nicola J.


    Altered phosphodiesterase (PDE)-cyclic AMP (cAMP) activity is frequently associated with anxiety disorders, but current therapies act by reducing neuronal excitability rather than targeting PDE-cAMP-mediated signaling pathways. Here, we report the novel repositioning of anti-cancer MEK inhibitors...... as anxiolytics in a zebrafish model of anxiety-like behaviors. PDE inhibitors or activators of adenylate cyclase cause behaviors consistent with anxiety in larvae and adult zebrafish. Small-molecule screening identifies MEK inhibitors as potent suppressors of cAMP anxiety behaviors in both larvae and adult...... zebrafish, while causing no anxiolytic behavioral effects on their own. The mechanism underlying cAMP-induced anxiety is via crosstalk to activation of the RAS-MAPK signaling pathway. We propose that targeting crosstalk signaling pathways can be an effective strategy for mental health disorders, and advance...

  18. Acetylation site specificities of lysine deacetylase inhibitors in human cells

    DEFF Research Database (Denmark)

    Schölz, Christian; Weinert, Brian Tate; Wagner, Sebastian A


    Lysine deacetylases inhibitors (KDACIs) are used in basic research, and many are being investigated in clinical trials for treatment of cancer and other diseases. However, their specificities in cells are incompletely characterized. Here we used quantitative mass spectrometry (MS) to obtain...... acetylation signatures for 19 different KDACIs, covering all 18 human lysine deacetylases. Most KDACIs increased acetylation of a small, specific subset of the acetylome, including sites on histones and other chromatin-associated proteins. Inhibitor treatment combined with genetic deletion showed...... that the effects of the pan-sirtuin inhibitor nicotinamide are primarily mediated by SIRT1 inhibition. Furthermore, we confirmed that the effects of tubacin and bufexamac on cytoplasmic proteins result from inhibition of HDAC6. Bufexamac also triggered an HDAC6-independent, hypoxia-like response by stabilizing HIF...

  19. HIV-1 Non-Nucleoside Reverse Transcriptase Inhibitors

    DEFF Research Database (Denmark)

    Vanangamudi, Murugesan; Poongavanam, Vasanthanathan; Namasivayam, Vigneshwaran


    BACKGROUND: Design of inhibitors for HIV-1 reverse transcriptase inhibition (HIV-1 RT) is one of the successful chemotherapies for the treatment of HIV infection. Among the inhibitors available for HIV-1 RT, non-nucleoside reverse transcriptase inhibitors (NNRTIs) have shown to be very promising...... and clinically approved drugs. However, the efficiency of many of these drugs has been reduced by the drug-resistant variants of HIV-1 RT. The aim of the current review is to provide a summary of lead optimization strategies from the 3D-QSARs studies on NNRTI class from the past 21 years (1995 to 2016). METHODS......, formimidoester disulfides, thiocarbamate, thiazolidinone derivatives, etc. have been discussed in detail. In addition, we explore the position of the functional groups that drive the protein-ligand interaction. RESULTS: The structure-activity relationship (SAR) revealed from CoMFA and CoMSIA studies...

  20. Marine-Derived Angiogenesis Inhibitors for Cancer Therapy

    Directory of Open Access Journals (Sweden)

    Ying-Qing Wang


    Full Text Available Angiogenesis inhibitors have been successfully used for cancer therapy in the clinic. Many marine-derived natural products and their analogues have been reported to show antiangiogenic activities. Compared with the drugs in the clinic, these agents display interesting characteristics, including diverse sources, unique chemical structures, special modes of action, and distinct activity and toxicity profiles. This review will first provide an overview of the current marine-derived angiogenesis inhibitors based on their primary targets and/or mechanisms of action. Then, the marine-derived antiangiogenic protein kinase inhibitors will be focused on. And finally, the clinical trials of the marine-derived antiangiogenic agents will be discussed, with special emphasis on their application potentials, problems and possible coping strategies in their future development as anticancer drugs.

  1. HDAC Inhibitors without an Active Site Zn2+-Binding Group

    DEFF Research Database (Denmark)

    Vickers, Chris J.; Olsen, Christian Adam; Leman, Luke J.


    Natural and synthetic histone deacetylase (HDAC) inhibitors generally derive their strong binding affinity and high potency from a key functional group that binds to the Zn2+ ion within the enzyme active site. However, this feature is also thought to carry the potential liability of undesirable off......-target interactions with other metalloenzymes. As a step toward mitigating this issue, here, we describe the design, synthesis, and structure−activity characterizations of cyclic α3β-tetrapeptide HDAC inhibitors that lack the presumed indispensable Zn2+-binding group. The lead compounds (e.g., 15 and 26) display good...... potency against class 1 HDACs and are active in tissue culture against various human cancer cell lines. Importantly, enzymological analysis of 26 indicates that the cyclic α3β-tetrapeptide is a fast-on/ off competitive inhibitor of HDACs 1−3 with Ki values of 49, 33, and 37 nM, respectively. Our proof...

  2. Structural Mechanism of the Pan-BCR-ABL Inhibitor Ponatinib (AP24534): Lessons for Overcoming Kinase Inhibitor Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Tianjun; Commodore, Lois; Huang, Wei-Sheng; Wang, Yihan; Thomas, Mathew; Keats, Jeff; Xu, Qihong; Rivera, Victor M.; Shakespeare, William C.; Clackson, Tim; Dalgarno, David C.; Zhu, Xiaotian (ARIAD)


    The BCR-ABL inhibitor imatinib has revolutionized the treatment of chronic myeloid leukemia. However, drug resistance caused by kinase domain mutations has necessitated the development of new mutation-resistant inhibitors, most recently against the T315I gatekeeper residue mutation. Ponatinib (AP24534) inhibits both native and mutant BCR-ABL, including T315I, acting as a pan-BCR-ABL inhibitor. Here, we undertook a combined crystallographic and structure-activity relationship analysis on ponatinib to understand this unique profile. While the ethynyl linker is a key inhibitor functionality that interacts with the gatekeeper, virtually all other components of ponatinib play an essential role in its T315I inhibitory activity. The extensive network of optimized molecular contacts found in the DFG-out binding mode leads to high potency and renders binding less susceptible to disruption by single point mutations. The inhibitory mechanism exemplified by ponatinib may have broad relevance to designing inhibitors against other kinases with mutated gatekeeper residues.

  3. BACE1 Inhibitor Peptides: Can an Infinitely Small k cat Value Turn the Substrate of an Enzyme into Its Inhibitor? (United States)

    Hamada, Yoshio; Ishiura, Shoichi; Kiso, Yoshiaki


    Recently, we reported substrate-based pentapeptidic β-secretase (BACE1) inhibitors with a hydroxymethylcarbonyl isostere as a substrate transition-state mimic. These inhibitors showed potent BACE1 inhibitory activity in enzyme and cell assays, with KMI-429 showing in vivo inhibition of Aβ production. We also designed and synthesized nonpeptidic and small-sized BACE1 inhibitors using "in-silico conformational structure-based design". By studying the structure-activity relationship of these inhibitors, we found that the σ-π interaction of an inhibitor with the BACE1-Arg235 side chain played a key role in the inhibition of BACE1. We speculated that a peptide capable of binding to the BACE1-Arg235 side chain via the σ-π interaction might exhibit BACE1 inhibitory activity. Hence, we designed and synthesized a series of peptides that were modified at the P2 position and found that some of these peptides exhibited a potent BACE1 inhibitory activity despite their structural similarity to the BACE1 substrate.

  4. Chelation: A Fundamental Mechanism of Action of AGE Inhibitors, AGE Breakers, and Other Inhibitors of Diabetes Complications

    Energy Technology Data Exchange (ETDEWEB)

    Nagai, Rhoji; Murray, David B.; Metz, Thomas O.; Baynes, John


    Advanced glycation or glycoxidation end-products (AGE) increase in tissue proteins with age, and their rate of accumulation is increased in diabetes, nephropathy and inflammatory diseases. AGE inhibitors include a range of compounds that are proposed to act by trapping carbonyl and dicarbonyl intermediates in AGE formation. However, some among the newer generation of AGE inhibitors lack reactive functional groups that would trap reaction intermediates, indicating an alternative mechanism of action. We propose that AGE inhibitors function primarily as chelators, inhibiting metal-catalyzed oxidation reactions. The AGE-inhibitory activity of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers is also consistent with their chelating activity. Finally, compounds described as AGE breakers, or their hydrolysis products, also have strong chelating activity, suggesting that these compounds also act through their chelating activity. We conclude that chelation is the common, and perhaps the primary, mechanism of action of AGE inhibitors and breakers, and that chronic, mild chelation therapy should prove useful in treatment of diabetes and age-related diseases characterized by oxidative stress, inflammation and increased chemical modification of tissue proteins by advanced glycoxidation and lipoxidation end-products.

  5. Selective serotonin reuptake inhibitors for fibromyalgia syndrome

    Directory of Open Access Journals (Sweden)

    Brian Walitt

    Full Text Available ABSTRACT BACKGROUND: Fibromyalgia is a clinically well-defined chronic condition with a biopsychosocial aetiology. Fibromyalgia is characterized by chronic widespread musculoskeletal pain, sleep problems, cognitive dysfunction, and fatigue. Patients often report high disability levels and poor quality of life. Since there is no specific treatment that alters the pathogenesis of fibromyalgia, drug therapy focuses on pain reduction and improvement of other aversive symptoms. OBJECTIVES: To assess the benefits and harms of selective serotonin reuptake inhibitors (SSRIs in the treatment of fibromyalgia. METHODS: Search methods: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 5, MEDLINE (1966 to June 2014, EMBASE (1946 to June 2014, and the reference lists of reviewed articles. Selection criteria: We selected all randomized, double-blind trials of SSRIs used for the treatment of fibromyalgia symptoms in adult participants. We considered the following SSRIs in this review: citalopram, fluoxetine, escitalopram, fluvoxamine, paroxetine, and sertraline. Data collection and analysis: Three authors extracted the data of all included studies and assessed the risks of bias of the studies. We resolved discrepancies by discussion. MAIN RESULTS: The quality of evidence was very low for each outcome. We downgraded the quality of evidence to very low due to concerns about risk of bias and studies with few participants. We included seven placebo-controlled studies, two with citalopram, three with fluoxetine and two with paroxetine, with a median study duration of eight weeks (4 to 16 weeks and 383 participants, who were pooled together. All studies had one or more sources of potential major bias. There was a small (10% difference in patients who reported a 30% pain reduction between SSRIs (56/172 (32.6% and placebo (39/171 (22.8% risk difference (RD 0.10, 95% confidence interval (CI 0.01 to 0.20; number needed to treat for an

  6. Selective serotonin reuptake inhibitors for fibromyalgia syndrome (United States)

    Walitt, Brian; Urrútia, Gerard; Nishishinya, María Betina; Cantrell, Sarah E; Häuser, Winfried


    Background Fibromyalgia is a clinically well-defined chronic condition with a biopsychosocial aetiology. Fibromyalgia is characterized by chronic widespread musculoskeletal pain, sleep problems, cognitive dysfunction, and fatigue. Patients often report high disability levels and poor quality of life. Since there is no specific treatment that alters the pathogenesis of fibromyalgia, drug therapy focuses on pain reduction and improvement of other aversive symptoms. Objectives The objective was to assess the benefits and harms of selective serotonin reuptake inhibitors (SSRIs) in the treatment of fibromyalgia. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 5), MEDLINE (1966 to June 2014), EMBASE (1946 to June 2014), and the reference lists of reviewed articles. Selection criteria We selected all randomized, double-blind trials of SSRIs used for the treatment of fibromyalgia symptoms in adult participants. We considered the following SSRIs in this review: citalopram, fluoxetine, escitalopram, fluvoxamine, paroxetine, and sertraline. Data collection and analysis Three authors extracted the data of all included studies and assessed the risks of bias of the studies. We resolved discrepancies by discussion. Main results The quality of evidence was very low for each outcome. We downgraded the quality of evidence to very low due to concerns about risk of bias and studies with few participants. We included seven placebo-controlled studies, two with citalopram, three with fluoxetine and two with paroxetine, with a median study duration of eight weeks (4 to 16 weeks) and 383 participants, who were pooled together. All studies had one or more sources of potential major bias. There was a small (10%) difference in patients who reported a 30% pain reduction between SSRIs (56/172 (32.6%)) and placebo (39/171 (22.8%)) risk difference (RD) 0.10, 95% confidence interval (CI) 0.01 to 0.20; number needed to treat for an additional

  7. Kinetic characterization of ebselen, chelerythrine and apomorphine as glutaminase inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Ajit G.; Rojas, Camilo [Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Tanega, Cordelle; Shen, Min; Simeonov, Anton; Boxer, Matthew B.; Auld, Douglas S. [National Center for Advancing Translational Sciences, National Institutes of Health, 9800 Medical Center Drive, Rockville, MD 20850 (United States); Ferraris, Dana V. [Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Tsukamoto, Takashi [Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Slusher, Barbara S., E-mail: [Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States); Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, MD 21205 (United States)


    Highlights: •Ebselen, chelerythrine and apomorphine were identified as glutaminase inhibitors. •These had greater affinities and efficiency of inhibition than known prototypes. •Their previously reported biological activity could be due to glutaminase inhibition. -- Abstract: Glutaminase catalyzes the hydrolysis of glutamine to glutamate and plays a central role in the proliferation of neoplastic cells via glutaminolysis, as well as in the generation of excitotoxic glutamate in central nervous system disorders such as HIV-associated dementia (HAD) and multiple sclerosis. Both glutaminase siRNA and glutaminase inhibition have been shown to be effective in in vitro models of cancer and HAD, suggesting a potential role for small molecule glutaminase inhibitors. However, there are no potent, selective inhibitors of glutaminase currently available. The two prototypical glutaminase inhibitors, BPTES and DON, are either insoluble or non-specific. In a search for more drug-like glutaminase inhibitors, we conducted a screen of 1280 in vivo active drugs (Library of Pharmacologically Active Compounds (LOPAC{sup 1280})) and identified ebselen, chelerythrine and (R)-apomorphine. The newly identified inhibitors exhibited 10 to 1500-fold greater affinities than DON and BPTES and over 100-fold increased efficiency of inhibition. Although non-selective, it is noteworthy that the affinity of ebselen for glutaminase is more potent than any other activity yet described. It is possible that the previously reported biological activity seen with these compounds is due, in part, to glutaminase inhibition. Ebselen, chelerythrine and apomorphine complement the armamentarium of compounds to explore the role of glutaminase in disease.

  8. Bosutinib: a novel second-generation tyrosine kinase inhibitor. (United States)

    Isfort, Susanne; Keller-v Amsberg, Gunhild; Schafhausen, Philippe; Koschmieder, Steffen; Brümmendorf, Tim H


    Bosutinib (SKI-606) is a 4-anilino-3-quinoline carbonitrile, which acts as a dual inhibitor of Src and ABL kinases. In addition, the BCR-ABL fusion gene product, a constitutively activated tyrosine kinase which is crucial for the development of chronic myeloid leukemia (CML), is highly sensitive to bosutinib. Interestingly, distinctly lower concentrations of bosutinib are required to ablate BCR-ABL phosphorylation when compared to the first-generation tyrosine kinase inhibitor imatinib (IM). Bosutinib is a potent inhibitor of CML cell proliferation in vitro and has demonstrated promising activity in CML patients resistant or intolerant to IM as well as in newly diagnosed patients with chronic phase CML (CML-CP). Remarkably, bosutinib has been found to be capable of overcoming the majority of IM-resistant BCR-ABL mutations. Bosutinib has the potency to induce deep and fast responses in second- and third-/fourth-line treatment, and as a consequence, the drug has recently been licensed for patients previously treated with one or more tyrosine kinase inhibitor(s) and for whom imatinib, nilotinib, and dasatinib are not considered appropriate treatment options. Due to its potency and differing toxicity profile, it promises to be a good therapeutic option for a defined cohort of patients. The most common side effects are gastrointestinal with most of the patients suffering from nausea, vomiting, or diarrhea. For the most part, these gastrointestinal symptoms occur early after treatment initiation, are manageable, and often self-limiting. Continuous monitoring of liver enzymes upon treatment initiation is necessary during bosutinib treatment. In addition to CML treatment, bosutinib has shown some efficacy in selected patients suffering from advanced-stage solid tumors. In conclusion, bosutinib is a promising novel small molecule inhibitor approved now for targeted therapy of CML and in clinical development for other malignancies.

  9. Merlin deficiency predicts FAK inhibitor sensitivity: a synthetic lethal relationship. (United States)

    Shapiro, Irina M; Kolev, Vihren N; Vidal, Christian M; Kadariya, Yuwaraj; Ring, Jennifer E; Wright, Quentin; Weaver, David T; Menges, Craig; Padval, Mahesh; McClatchey, Andrea I; Xu, Qunli; Testa, Joseph R; Pachter, Jonathan A


    The goal of targeted therapy is to match a selective drug with a genetic lesion that predicts for drug sensitivity. In a diverse panel of cancer cell lines, we found that the cells most sensitive to focal adhesion kinase (FAK) inhibition lack expression of the neurofibromatosis type 2 (NF2) tumor suppressor gene product, Merlin. Merlin expression is often lost in malignant pleural mesothelioma (MPM), an asbestos-induced aggressive cancer with limited treatment options. Our data demonstrate that low Merlin expression predicts for increased sensitivity of MPM cells to a FAK inhibitor, VS-4718, in vitro and in tumor xenograft models. Disruption of MPM cell-cell or cell-extracellular matrix (ECM) contacts with blocking antibodies suggests that weak cell-cell adhesions in Merlin-negative MPM cells underlie their greater dependence on cell-ECM-induced FAK signaling. This provides one explanation of why Merlin-negative cells are vulnerable to FAK inhibitor treatment. Furthermore, we validated aldehyde dehydrogenase as a marker of cancer stem cells (CSCs) in MPM, a cell population thought to mediate tumor relapse after chemotherapy. Whereas pemetrexed and cisplatin, standard-of-care agents for MPM, enrich for CSCs, FAK inhibitor treatment preferentially eliminates these cells. These preclinical results provide the rationale for a clinical trial in MPM patients using a FAK inhibitor as a single agent after first-line chemotherapy. With this design, the FAK inhibitor could potentially induce a more durable clinical response through reduction of CSCs along with a strong antitumor effect. Furthermore, our data suggest that patients with Merlin-negative tumors may especially benefit from FAK inhibitor treatment. Copyright © 2014, American Association for the Advancement of Science.

  10. Uncovering Molecular Bases Underlying Bone Morphogenetic Protein Receptor Inhibitor Selectivity.

    Directory of Open Access Journals (Sweden)

    Abdelaziz Alsamarah

    Full Text Available Abnormal alteration of bone morphogenetic protein (BMP signaling is implicated in many types of diseases including cancer and heterotopic ossifications. Hence, small molecules targeting BMP type I receptors (BMPRI to interrupt BMP signaling are believed to be an effective approach to treat these diseases. However, lack of understanding of the molecular determinants responsible for the binding selectivity of current BMP inhibitors has been a big hindrance to the development of BMP inhibitors for clinical use. To address this issue, we carried out in silico experiments to test whether computational methods can reproduce and explain the high selectivity of a small molecule BMP inhibitor DMH1 on BMPRI kinase ALK2 vs. the closely related TGF-β type I receptor kinase ALK5 and vascular endothelial growth factor receptor type 2 (VEGFR2 tyrosine kinase. We found that, while the rigid docking method used here gave nearly identical binding affinity scores among the three kinases; free energy perturbation coupled with Hamiltonian replica-exchange molecular dynamics (FEP/H-REMD simulations reproduced the absolute binding free energies in excellent agreement with experimental data. Furthermore, the binding poses identified by FEP/H-REMD led to a quantitative analysis of physical/chemical determinants governing DMH1 selectivity. The current work illustrates that small changes in the binding site residue type (e.g. pre-hinge region in ALK2 vs. ALK5 or side chain orientation (e.g. Tyr219 in caALK2 vs. wtALK2, as well as a subtle structural modification on the ligand (e.g. DMH1 vs. LDN193189 will cause distinct binding profiles and selectivity among BMP inhibitors. Therefore, the current computational approach represents a new way of investigating BMP inhibitors. Our results provide critical information for designing exclusively selective BMP inhibitors for the development of effective pharmacotherapy for diseases caused by aberrant BMP signaling.

  11. Benzoselendiazole-based responsive long-lifetime photoluminiscent probes for protein kinases

    DEFF Research Database (Denmark)

    Ekambaram, R; Enkvist, E; Manoharan, GB


    Benzoselenadiazole-containing inhibitors of protein kinases were constructed and their capability to emit phosphorescence in the kinase-bound state was established. Labelling of the inhibitors with a red fluorescent dye led to sensitive responsive photoluminescent probes for protein kinase CK2 th...

  12. Removal of inhibitors from lignocellulosic hydrolyzates by vacuum membrane distillation. (United States)

    Chen, Jingwen; Zhang, Yaqin; Wang, Yafei; Ji, Xiaosheng; Zhang, Lin; Mi, Xigeng; Huang, He


    In this study, vacuum membrane distillation (VMD) was used to remove two prototypical fermentation inhibitors (acetic acid and furfural) from lignocellulose hydrolyzates. The effect of operating parameters, such as feed temperature and feed velocity, on the removal efficiencies of inhibitors was investigated. Under optimal conditions, more than 98% of furfural could be removed by VMD. However, the removal efficiency of acetic acid was considerably lower. After furfural and acetic acid were selectively removed from hydrolyzates by VMD, ethanol production efficiency increased by 17.8% compared to original hydrolyzates. Copyright © 2013 Elsevier Ltd. All rights reserved.

  13. Arginase Inhibitor in the Pharmacological Correction of Endothelial Dysfunction (United States)

    Pokrovskiy, Mihail V.; Korokin, Mihail V.; Tsepeleva, Svetlana A.; Pokrovskaya, Tatyana G.; Gureev, Vladimir V.; Konovalova, Elena A.; Gudyrev, Oleg S.; Kochkarov, Vladimir I.; Korokina, Liliya V.; Dudina, Eleonora N.; Babko, Anna V.; Terehova, Elena G.


    This paper is about a way of correction of endothelial dysfunction with the inhibitor of arginase: L-norvaline. There is an imbalance between vasoconstriction and vasodilatation factors of endothelium on the basis of endothelial dysfunction. Among vasodilatation agents, nitrogen oxide plays the basic role. Amino acid L-arginine serves as a source of molecules of nitrogen oxide in an organism. Because of the high activity of arginase enzyme which catalyzes the hydrolysis of L-arginine into ornithine and urea, the bioavailability of nitrogen oxide decreases. The inhibitors of arginase suppress the activity of the given enzyme, raising and production of nitrogen oxide, preventing the development of endothelial dysfunction. PMID:21747978

  14. Design, Synthesis, and Biological Evaluation of PKD Inhibitors

    Directory of Open Access Journals (Sweden)

    Marie-Céline Frantz


    Full Text Available Protein kinase D (PKD belongs to a family of serine/threonine kinases that play an important role in basic cellular processes and are implicated in the pathogenesis of several diseases. Progress in our understanding of the biological functions of PKD has been limited due to the lack of a PKD-specific inhibitor. The benzoxoloazepinolone CID755673 was recently reported as the first potent and kinase-selective inhibitor for this enzyme. For structure-activity analysis purposes, a series of analogs was prepared and their in vitro inhibitory potency evaluated.

  15. Investigating the Different Dimensions of DPP-4 Inhibitors

    Directory of Open Access Journals (Sweden)

    Heinz Drexel


    Full Text Available This Takeda-sponsored European Association for the Study of Diabetes (EASD symposium addressed the pharmacology, clinical use, and future therapeutic application of dipeptidyl-peptidase-4 (DPP-4 inhibitors. The scientific programme covered the clinical efficacy of DPP-4 inhibitors, their durability in clinical practice, and their use in combination therapy with other antidiabetic drugs. The important issue of the effect of this class of drugs on cardiovascular (CV outcomes was also explored. The symposium was chaired by Prof Heinz Drexel and included insightful talks from an expert faculty comprising of Profs Jørgen Rungby, Jochen Seufert, and Kausik Ray.

  16. Calpain inhibitor nanocrystals prepared using Nano Spray Dryer B-90 (United States)

    Baba, Koichi; Nishida, Kohji


    The Nano Spray Dryer B-90 offers a new, simple, and alternative approach for the production of drug nanocrystals. Among attractive drugs, calpain inhibitor that inhibits programmed cell death `apoptosis' is a candidate for curing apoptosis-mediated intractable diseases such as Alzheimer's disease and Parkinson's disease. In this study, the preparation of calpain inhibitor nanocrystals using Nano Spray Dryer B-90 was demonstrated. The particle sizes were controlled by means of selecting mesh aperture sizes. The obtained average particle sizes were in the range of around 300 nm to submicron meter.

  17. Stabilization of Torpedo californica acetylcholinesterase by reversible inhibitors. (United States)

    Weiner, Lev; Shnyrov, Valery L; Konstantinovskii, Leonid; Roth, Esther; Ashani, Yacov; Silman, Israel


    The dimeric form of Torpedo californica acetylcholinesterase provides a valuable experimental system for studying transitions between native, partially unfolded, and unfolded states since long-lived partially unfolded states can be generated by chemical modification of a nonconserved buried cysteine residue, Cys 231, by denaturing agents, by oxidative stress, and by thermal inactivation. Elucidation of the 3D structures of complexes of Torpedo californica acetylcholinesterase with a repertoire of reversible inhibitors permits their classification into three categories: (a) active-site directed inhibitors, which interact with the catalytic anionic subsite, at the bottom of the active-site gorge, such as edrophonium and tacrine; (b) peripheral anionic site inhibitors, which interact with a site at the entrance to the gorge, such as propidium and d-tubocurarine; and (c) elongated gorge-spanning inhibitors, which bridge the two sites, such as BW284c51 and decamethonium. The effects of these three categories of reversible inhibitors on the stability of Torpedo californica acetylcholinesterase were investigated using spectroscopic techniques and differential scanning calorimetry. Thermodynamic parameters obtained calorimetrically permitted quantitative comparison of the effects of the inhibitors on the enzyme's thermal stability. Peripheral site inhibitors had a relatively small effect, while gorge-spanning ligands and those binding at the catalytic anionic site, had a much larger stabilizing effect. The strongest effect was, however, observed with the polypeptide toxin, fasciculin II (FasII), even though, in terms of its binding site, it belongs to the category of peripheral site ligands. The stabilizing effect of the ligands binding at the anionic subsite of the active site, like that of the gorge-spanning ligands, may be ascribed to their capacity to stabilize the interaction between the two subdomains of the enzyme. The effect of fasciculin II may be ascribed to the

  18. Non-genetic risk factors in haemophilia A inhibitor management

    DEFF Research Database (Denmark)

    Löfgren, Karin Maria; Søndergaard, H.; Skov, Søren


    In haemophilia A (HA) management, antidrug antibodies, or inhibitors, are a serious complication that renders factor VIII (FVIII) replacement therapy ineffective, increases morbidity and reduces quality of life for affected patients. Inhibitor development aetiology is multifactorial and covers both......, and explanations for this association are being investigated. A potential explanation is the danger signal effect, where the immune response is activated by endogenous or exogenous danger or damage signals present at the time and site of FVIII administration. The danger theory explains how alarm signals from...

  19. Prevention of Corrosion Rate by Natural Inhibitor Papaya Leaf Extract


    Bow, Yohandri


    Corrosion is an event of damage or deterioration of a metal caused by reaction with the environtment. Corrosion process can be prevented by the addition of corrosion inhibitor. Papaya leaf extract is an organic material that could potentially be used as a corrosion inhibitor because it contains N-acetyl- glukosamida and amino acid. The purpose of this study is to determine the effects of brine concentration and surface area on the rate of corrosion of a metal plate that can be used as refere...

  20. Green chemistry applied to corrosion and scale inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Darling, D.; Rakshpal, R. [Environmental Protection Agency, Washington, DC (United States)


    Numerous breakthroughs in environmental protection and pollution prevention have been realized in recent years by both industry and academia through the application of green chemistry principles. Green chemistry, or pollution prevention at the molecular level, is chemistry designed to reduce or eliminate the use or generation of hazardous materials associated with the manufacture and application of chemicals. The application of the green chemistry principles to the areas of corrosion and scale inhibitors has resulted in the reduction/elimination of many of the more toxic inhibitors and the development of newer, more environmentally friendly ones.

  1. Synthesis of some natural sulphonamide derivatives as carbonic anhydrase inhibitors

    Directory of Open Access Journals (Sweden)

    Taner Gokcen


    Full Text Available Carbonic anhydrase inhibitors are both in clinical use as antiglaucoma, diuretics, antiepileptics and management of altitude sickness, and under investigation as anticancer, anticonvulsant and antiobesity agents. Sulphonamides have been known for decades as carbonic anhydrase inhibitors and are in clinical use. Sulphonamide derivatives of p-hydroxybenzoic acid and 3,4,5-trihydroxybenzoic acid (gallic acid were synthesized and their inhibition values over hCA I and hCA II isozymes, purified from human erythrocyte cells by Sepharose-4B-L-tyrosine-sulphanilamide, were determined. Compounds synthesized showed efficient carbonic anhydrase inhibition activity at low nM levels.

  2. Synthesis of brequinar analogue inhibitors of malaria parasite dihydroorotate dehydrogenase. (United States)

    Boa, Andrew N; Canavan, Shane P; Hirst, Paul R; Ramsey, Christopher; Stead, Andrew M W; McConkey, Glenn A


    A series of 2-phenyl quinoline-4-carboxylic acid derivatives related to brequinar, an inhibitor of human dihydroorotate dehydrogenase (DHODH), has been prepared and evaluated as inhibitors of DHODH from the malaria parasite Plasmodium falciparum. Brequinar was essentially inactive against PfDHODH (IC(50) 880 microM) whereas several members of the series inhibited PfDHODH. Unexpectedly, replacement of the carboxylic acid required for brequinar to inhibit hDHODH was not essential in the diisopropylamides that inhibited PfDHODH.

  3. Mitigation of Mild Steel Corrosion in Acidic Solution Using Inhibitor

    Directory of Open Access Journals (Sweden)

    M. Vishnudevan


    Full Text Available The inhibition efficiency of mild steel corrosion in HCl acidic solution containing various concentrations of mixed inhibitors were evaluated by conducting Tafel polarization and electrochemical impedance studies. The mixed inhibitors used in this present investigation were trisodium citrate and sodium benzoate. In this present investigation 0.01 N to 0.1 N concentrations of HCl was used at 30 °C. Sodium benzoate present in the mixed inhibitive system enhanced the inhibition efficiency through chemisorptions. The maximum inhibition efficiency ( 95.4% was obtained for the mixed inhibitive system containing 0.05 M citrate and 0.5 M benzoate in 0.1 N HCl.

  4. Discovery of potent macrocyclic HCV NS5A inhibitors. (United States)

    Yu, Wensheng; Vibulbhan, Bancha; Rosenblum, Stuart B; Martin, Gregory S; Vellekoop, A Samuel; Holst, Christian L; Coburn, Craig A; Wong, Michael; Selyutin, Oleg; Ji, Tao; Zhong, Bin; Hu, Bin; Chen, Lei; Dwyer, Michael P; Jiang, Yueheng; Nair, Anilkumar G; Tong, Ling; Zeng, Qingbei; Agrawal, Sony; Carr, Donna; Rokosz, Laura; Liu, Rong; Curry, Stephanie; McMonagle, Patricia; Ingravallo, Paul; Lahser, Fred; Asante-Appiah, Ernest; Fells, James; Kozlowski, Joseph A


    HCV NS5A inhibitors have demonstrated impressive in vitro virologic profiles in HCV replicon assays and robust HCV RNA titer reduction in the clinic making them attractive components for inclusion in an all oral fixed-dose combination (FDC) regimen for the treatment of HCV infection. Merck's effort in this area identified MK-4882 and MK-8325 as early development leads. Herein, we describe the discovery of potent macrocyclic NS5A inhibitors bearing the MK-8325 or MK-4882 core structure. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Advances in development of phosphatidylinositol 3-kinase inhibitors. (United States)

    Kong, Dexin; Yamori, Takao


    Phosphatidylinositol 3-kinases (PI3Ks) are a class of lipid kinases that phosphorylate phosphatidylinositol 4,5-bisphosphate (PIP2) at the 3-OH of the inositol ring to generate phosphatidylinositol 3,4,5-trisphosphate (PIP3), which in turn activates Akt and the downstream effectors like mTOR, and therefore play important roles in cell growth, survival, etc. The phosphatase and tensin homolog deleted in chromosome ten (PTEN), acts as the catalytic antagonist of PI3K by dephosphorylating PIP3 to PIP2. PI3K has become an important drug target for cancer therapy, since gain-of-function mutations of PIK3CA encoding PI3Kalpha, as well as loss-of-function mutations of PTEN, have been frequently found in human cancers. The pharmaceutical development of PI3K inhibitors has made a great leap forward during the last 3 years. While PI3Kbeta, delta and gamma isoform-specific PI3K inhibitors (TGX-221, IC87114 and AS-605240) have been developed for therapy of coronary heart disease, asthma, and glomerulonephritis, respectively, a promising PI3Kalpha specific inhibitor is not yet available. Correspondingly, almost all of the promising PI3K inhibitors under development for caner therapy, such as NVP-BEZ235, GDC-0941 and ZSTK474, are pan-PI3K isoform inhibitors. Each of these pan-PI3K inhibitors seems to induce a common G1 phase arrest. All have shown favorable in vivo anticancer efficacies and low toxicities, and therefore most have entered evaluation in clinical trials. P-Akt and p-S6 have been reported to be feasible pharmacodynamic biomarkers for monitoring the efficacy of these agents. In the process of discovery of these and other PI3K inhibitors, detailed structure-activity relationship studies were carried out. This review summarizes key advances in the development of PI3K inhibitors, which is preceded by an introduction of PI3K family and their functions.

  6. Cyclo-oxygenase (COX) inhibitors for treating preterm labour. (United States)

    Reinebrant, Hanna E; Pileggi-Castro, Cynthia; Romero, Carla L T; Dos Santos, Rafaela A N; Kumar, Sailesh; Souza, João Paulo; Flenady, Vicki


    Preterm birth is a major cause of perinatal mortality and morbidity. Cyclo-oxygenase (COX) inhibitors inhibit uterine contractions, are easily administered and appear to have few maternal side effects. However, adverse effects have been reported in the fetus and newborn as a result of exposure to COX inhibitors. To assess the effects on maternal and neonatal outcomes of COX inhibitors administered as a tocolytic agent to women in preterm labour when compared with (i) placebo or no intervention and (ii) other tocolytics. In addition, to compare the effects of non-selective COX inhibitors with COX-2 selective inhibitors. We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (24 August 2014). We also contacted recognised experts and searched reference lists of retrieved studies. All published and unpublished randomised trials in which COX inhibitors were used for tocolysis for women in labour between 20 and 36 completed weeks' gestation. Two review authors independently evaluated methodological quality and extracted data. We sought additional information from study authors. Results are presented using risk ratio (RR; dichotomous data) and mean difference (MD; continuous data) with 95% confidence interval (CI). The number needed to treat for benefit (NNTB) and the number needed to treat for harm (NNTH) were calculated for statistically different categorical outcomes. With the addition of seven studies with a total of 684 women, this review now includes outcome data from 20 studies including 1509 women. The non-selective COX inhibitor indomethacin was used in 15 studies. The overall quality of the included studies was considered moderate to low.Three small studies (102 women), two of which were conducted in the 1980's, compared COX inhibition (indomethacin only) with placebo. No difference was shown in birth less than 48 hours after trial entry (average RR 0.20, 95% CI 0.03 to 1.28; two studies with 70 women). Indomethacin resulted in a reduction in

  7. Clays valorization as corrosion inhibitors for E400 reinforcing steel

    Directory of Open Access Journals (Sweden)

    Gassama Diadioly


    Full Text Available The behavior of E400 steel, a constructional steel widely used in Senegal, was studied in aqueous NaCl solution in the presence of two types of clay: volcanic tuffs, and sedimentary montmorillonite. The protection efficiency of these compounds were electrochemically assessed (corrosion potential variation curves, polarization curves and electrochemical impedance spectroscopy at various inhibitor contents. The results obtained showed that these inhibitors present an inhibitory efficacy of about 70% for an optimal concentration of 0.60% for the tuffs and 62% for a maximum content of 0.50% for montmorillonite.

  8. Novel ROCK inhibitors for the treatment of pulmonary arterial hypertension

    Energy Technology Data Exchange (ETDEWEB)

    Shaw, Duncan; Hollingworth, Greg; Soldermann, Nicolas; Sprague, Elizabeth; Schuler, Walter; Vangrevelinghe, Eric; Duggan, Nicholas; Thomas, Matthew; Kosaka, Takatoshi; Waters, Nigel; van Eis, Maurice J.


    A novel class of selective inhibitors of ROCK1 and ROCK2 has been identified by structural based drug design. PK/PD experiments using a set of highly selective Rho kinase inhibitors suggest that systemic Rho kinase inhibition is linked to a reversible reduction in lymphocyte counts. These results led to the consideration of topical delivery of these molecules, and to the identification of a lead molecule 7 which shows promising PK and PD in a murine model of pulmonary hypertension after intra-tracheal dosing.

  9. Alternative Agents in Type 1 Diabetes in Addition to Insulin Therapy: Metformin, Alpha-Glucosidase Inhibitors, Pioglitazone, GLP-1 Agonists, DPP-IV Inhibitors, and SGLT-2 Inhibitors. (United States)

    DeGeeter, Michelle; Williamson, Bobbie


    Insulin is the mainstay of current treatment for patients with type 1 diabetes mellitus (T1DM). Due to increasing insulin resistance, insulin doses are often continually increased, which may result in weight gain for patients. Medications currently approved for the treatment of type 2 diabetes offer varying mechanisms of action that can help to reduce insulin resistance and prevent or deter weight gain. A MEDLINE search was conducted to review literature evaluating the use of metformin, alpha-glucosidase inhibitors, pioglitazone, glucagon-like peptide 1 agonists, dipeptidyl peptidase, and sodium-dependent glucose transporter 2 inhibitors, in patients with T1DM. Varying results were found with some benefits including reductions in hemoglobin A1c, decreased insulin doses, and favorable effects on weight. Of significance, a common fear of utilizing multiple therapies for diabetes treatment is the risk of hypoglycemia, and this review displayed limited evidence of hypoglycemia with multiple agents. © The Author(s) 2014.

  10. Dipeptidylpeptidase-4 inhibitors (gliptins): focus on drug-drug interactions. (United States)

    Scheen, André J


    Patients with type 2 diabetes mellitus (T2DM) are generally treated with many pharmacological compounds and are exposed to a high risk of drug-drug interactions. Indeed, blood glucose control usually requires a combination of various glucose-lowering agents, and the recommended global approach to reduce overall cardiovascular risk generally implies administration of several protective compounds, including HMG-CoA reductase inhibitors (statins), antihypertensive compounds and antiplatelet agents. New compounds have been developed to improve glucose-induced beta-cell secretion and glucose control, without inducing hypoglycaemia or weight gain, in patients with T2DM. Dipeptidylpeptidase-4 (DPP-4) inhibitors are novel oral glucose-lowering agents, which may be used as monotherapy or in combination with other antidiabetic compounds, metformin, thiazolidinediones or even sulfonylureas. Sitagliptin, vildagliptin and saxagliptin are already on the market, either as single agents or in fixed-dose combined formulations with metformin. Other compounds, such as alogliptin and linagliptin, are in a late phase of development. This review summarizes the available data on drug-drug interactions reported in the literature for these five DDP-4 inhibitors: sitagliptin, vildagliptin, saxagliptin, alogliptin and linagliptin. Possible pharmacokinetic interferences have been investigated between each of these compounds and various pharmacological agents, which were selected because there are other glucose-lowering agents (metformin, glibenclamide [glyburide], pioglitazone/rosiglitazone) that may be prescribed in combination with DPP-4 inhibitors, other drugs that are currently used in patients with T2DM (statins, antihypertensive agents), compounds that are known to interfere with the cytochrome P450 (CYP) system (ketoconazole, diltiazem, rifampicin [rifampin]) or with P-glycoprotein transport (ciclosporin), or agents with a narrow therapeutic safety window (warfarin, digoxin). Generally

  11. Use of selective-serotonin reuptake inhibitors and platelet aggregation inhibitors among individuals with co-occurring atherosclerotic cardiovascular disease and depression or anxiety

    Directory of Open Access Journals (Sweden)

    J Douglas Thornton


    Full Text Available Objective: Medications commonly used to treat heart disease, anxiety, and depression can interact resulting in an increased risk of bleeding, warranting a cautious approach in medical decision making. This retrospective, descriptive study examined the prevalence and the factors associated with the use of both selective-serotonin reuptake inhibitor and platelet aggregation inhibitor among individuals with co-occurring atherosclerotic cardiovascular disease and anxiety or depression. Methods: Respondents aged 22 years and older, alive throughout the study period, and diagnosed with co-occurring atherosclerotic cardiovascular disease and anxiety or depression (n = 1507 in years 2007 through 2013 of the Medical Expenditures Panel Survey were included. The use of treatment was grouped as follows: selective-serotonin reuptake inhibitor and platelet aggregation inhibitor, selective-serotonin reuptake inhibitor or platelet aggregation inhibitor, and neither selective-serotonin reuptake inhibitor nor platelet aggregation inhibitor. Results: Overall, 16.5% used both selective-serotonin reuptake inhibitor and platelet aggregation inhibitor, 61.2% used selective-serotonin reuptake inhibitor or platelet aggregation inhibitor, and 22.3% used neither selective-serotonin reuptake inhibitor nor platelet aggregation inhibitor. Respondents aged over 65 years (adjusted odds ratio = 1.93 (95% confidence interval = 1.08–3.45 and having a diagnosis of diabetes (adjusted odds ratio = 1.63 (95% confidence interval = 1.15–2.31 and hypertension (adjusted odds ratio = 1.84 (95% confidence interval = 1.04–3.27 were more likely to be prescribed the combination. Conclusion: The drug interaction was prevalent in patients who are already at higher risk of health disparities and worse outcomes thus requiring vigilant evaluation.

  12. Moving towards dose individualization of tyrosine kinase inhibitors

    NARCIS (Netherlands)

    Klümpen, Heinz-Josef; Samer, Caroline F.; Mathijssen, Ron H. J.; Schellens, Jan H. M.; Gurney, Howard


    Molecular targeted therapies with tyrosine kinase inhibitors (TKIs) have been a recent breakthrough in cancer treatment. These small molecules are mainly used at a fixed dose ignoring the possible need for dose individualization. Fixed dosing may indeed result in suboptimal treatment or excessive

  13. Comparative review of dipeptidyl peptidase-4 inhibitors and sulphonylureas

    DEFF Research Database (Denmark)

    Deacon, Carolyn F.; Lebovitz, HE


    shown not to increase cardiovascular risk in large prospective safety trials. Because of these factors, DPP-4 inhibitors have become an established therapy for T2DM and are increasingly being positioned earlier in treatment algorithms. The present article reviews these two classes of oral antidiabetic...

  14. Individualized dosing of calcineurin inhibitors in renal transplantation

    NARCIS (Netherlands)

    Press, Rogier Raphael


    Calcineurin inhibitors are crucial in the prevention of acute rejection in the first year after renal transplantation. Unfortunately, these drugs (ciclosporin A, tacrolimus) are characterized by serious clinical toxicity and between patient variability in their effect. Therefore, the dose of these

  15. Use of antacids, alginates and proton pump inhibitors

    DEFF Research Database (Denmark)

    Lødrup, Anders; Reimer, Christine; Bytzer, Peter


    OBJECTIVE: Both over-the-counter medicine, such as antacids or alginates, and proton pump inhibitors (PPI) are used for treating acid-related disorders. We sought to describe what characterizes users of these different medicines, including long-term PPI users within the general population. METHOD...

  16. Use of proton pump inhibitors and the risk of listeriosis

    DEFF Research Database (Denmark)

    Jensen, Anne Kvistholm; Simonsen, Jacob; Ethelberg, Steen


    BACKGROUND: Recent studies suggest that proton pump inhibitors (PPIs) may increase the risk for listeriosis. We aimed to investigate a potential association in cases of non-pregnancy associated listeriosis, using registry data. METHODS: We conducted a population-based case-control study using...

  17. Biochemical Importance of Glycosylation of Plasminogen Activator Inhibitor-1

    DEFF Research Database (Denmark)

    Gils, Ann; Pedersen, Katrine Egelund; Skottrup, Peter


    The serpin plasminogen activator inhibitor-1 (PAI-1) is a potential target for anti-thrombotic and anti-cancer therapy. PAI-1 has 3 potential sites for N-linked glycosylation. We demonstrate here that PAI-1 expressed recombinantly or naturally by human cell lines display a heterogeneous...

  18. Docking and scoring of metallo-beta-lactamases inhibitors

    DEFF Research Database (Denmark)

    Olsen, Lars; Pettersson, Ingrid; Hemmingsen, Lars


    The performance of the AutoDock, GOLD and FlexX docking programs was evaluated for docking of dicarboxylic acid inhibitors into metallo-beta-lactamases (MBLs). GOLD provided the best overall performance, with RMSDs between experimental and docked structures of 1.8-2.6 A and a good correlation bet...

  19. Mammalian target of rapamycin inhibitor-associated stomatitis

    NARCIS (Netherlands)

    Boers-Doets, Christine B.; Raber-Durlacher, Judith E.; Treister, Nathaniel S.; Epstein, Joel B.; Arends, Anniek B. P.; Wiersma, Diede R.; Lalla, Rajesh V.; Logan, Richard M.; van Erp, Nielka P.; Gelderblom, Hans


    With the recent introduction of inhibitors of mammalian target of rapamycin (mTOR) in oncology, distinct cutaneous and oral adverse events have been identified. In fact, stomatitis and rash are documented as the most frequent and potentially dose-limiting side effects. Clinically, mTOR

  20. Selective serotonin reuptake inhibitors for depression in pregnancy. (United States)

    Susser, Leah C; Sansone, Stephanie A; Hermann, Alison D


    Perinatal depression is associated with a high risk of morbidity and mortality and may have long-term consequences on child development. The US Preventive Services Task Force has recently recognized the importance of identifying and treating women with depression in the perinatal period. However, screening and accessing appropriate treatment come with logistical challenges. In many areas, there may not be sufficient access to psychiatric care, and, until these resources develop, the burden may inadvertently fall on obstetricians. As a result, understanding the risks of perinatal depression in comparison with the risks of treatment is important. Many studies of selective serotonin reuptake inhibitors in pregnancy fail to control for underlying depressive illness, which can lead to misinterpretation of selective serotonin reuptake inhibitor risk by clinicians. This review discusses the risks and benefits of selective serotonin reuptake inhibitor treatment in pregnancy within the context of perinatal depression. Whereas selective serotonin reuptake inhibitors may be associated with certain risks, the absolute risks are low and may be outweighed by the risks of untreated depression for many women and their offspring. Copyright © 2016 Elsevier Inc. All rights reserved.