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Sample records for non-peptide cell-permeable potent

  1. Highly Potent Cell-Permeable and Impermeable NanoLuc Luciferase Inhibitors.

    Science.gov (United States)

    Walker, Joel R; Hall, Mary P; Zimprich, Chad A; Robers, Matthew B; Duellman, Sarah J; Machleidt, Thomas; Rodriguez, Jacquelynn; Zhou, Wenhui

    2017-04-21

    Novel engineered NanoLuc (Nluc) luciferase being smaller, brighter, and superior to traditional firefly (Fluc) or Renilla (Rluc) provides a great opportunity for the development of numerous biological, biomedical, clinical, and food and environmental safety applications. This new platform created an urgent need for Nluc inhibitors that could allow selective bioluminescent suppression and multiplexing compatibility with existing luminescence or fluorescence assays. Starting from thienopyrrole carboxylate 1, a hit from a 42 000 PubChem compound library with a low micromolar IC50 against Nluc, we derivatized four different structural fragments to discover a family of potent, single digit nanomolar, cell permeable inhibitors. Further elaboration revealed a channel that allowed access to the external Nluc surface, resulting in a series of highly potent cell impermeable Nluc inhibitors with negatively charged groups likely extending to the protein surface. The permeability was evaluated by comparing EC50 shifts calculated from both live and lysed cells expressing Nluc cytosolically. Luminescence imaging further confirmed that cell permeable compounds inhibit both intracellular and extracellular Nluc, whereas less permeable compounds differentially inhibit extracellular Nluc and Nluc on the cell surface. The compounds displayed little to no toxicity to cells and high luciferase specificity, showing no activity against firefly luciferase or even the closely related NanoBit system. Looking forward, the structural motifs used to gain access to the Nluc surface can also be appended with other functional groups, and therefore interesting opportunities for developing assays based on relief-of-inhibition can be envisioned.

  2. Discovery of a Highly Potent, Cell-Permeable Macrocyclic Peptidomimetic (MM-589) Targeting the WD Repeat Domain 5 Protein (WDR5)–Mixed Lineage Leukemia (MLL) Protein–Protein Interaction

    Energy Technology Data Exchange (ETDEWEB)

    Karatas, Hacer; Li, Yangbing; Liu, Liu; Ji, Jiao; Lee, Shirley; Chen, Yong; Yang, Jiuling; Huang, Liyue; Bernard, Denzil; Xu, Jing; Townsend, Elizabeth C.; Cao, Fang; Ran, Xu; Li, Xiaoqin; Wen, Bo; Sun, Duxin; Stuckey, Jeanne A; Lei, Ming; Dou, Yali; Wang, Shaomeng (Michigan)

    2017-06-06

    We report herein the design, synthesis, and evaluation of macrocyclic peptidomimetics that bind to WD repeat domain 5 (WDR5) and block the WDR5–mixed lineage leukemia (MLL) protein–protein interaction. Compound 18 (MM-589) binds to WDR5 with an IC50 value of 0.90 nM (Ki value <1 nM) and inhibits the MLL H3K4 methyltransferase (HMT) activity with an IC50 value of 12.7 nM. Compound 18 potently and selectively inhibits cell growth in human leukemia cell lines harboring MLL translocations and is >40 times better than the previously reported compound MM-401. Cocrystal structures of 16 and 18 complexed with WDR5 provide structural basis for their high affinity binding to WDR5. Additionally, we have developed and optimized a new AlphaLISA-based MLL HMT functional assay to facilitate the functional evaluation of these designed compounds. Compound 18 represents the most potent inhibitor of the WDR5–MLL interaction reported to date, and further optimization of 18 may yield a new therapy for acute leukemia.

  3. 8-Substituted Pyrido[3,4-d]pyrimidin-4(3H)-one Derivatives As Potent, Cell Permeable, KDM4 (JMJD2) and KDM5 (JARID1) Histone Lysine Demethylase Inhibitors.

    Science.gov (United States)

    Bavetsias, Vassilios; Lanigan, Rachel M; Ruda, Gian Filippo; Atrash, Butrus; McLaughlin, Mark G; Tumber, Anthony; Mok, N Yi; Le Bihan, Yann-Vaï; Dempster, Sally; Boxall, Katherine J; Jeganathan, Fiona; Hatch, Stephanie B; Savitsky, Pavel; Velupillai, Srikannathasan; Krojer, Tobias; England, Katherine S; Sejberg, Jimmy; Thai, Ching; Donovan, Adam; Pal, Akos; Scozzafava, Giuseppe; Bennett, James M; Kawamura, Akane; Johansson, Catrine; Szykowska, Aleksandra; Gileadi, Carina; Burgess-Brown, Nicola A; von Delft, Frank; Oppermann, Udo; Walters, Zoe; Shipley, Janet; Raynaud, Florence I; Westaway, Susan M; Prinjha, Rab K; Fedorov, Oleg; Burke, Rosemary; Schofield, Christopher J; Westwood, Isaac M; Bountra, Chas; Müller, Susanne; van Montfort, Rob L M; Brennan, Paul E; Blagg, Julian

    2016-02-25

    We report the discovery of N-substituted 4-(pyridin-2-yl)thiazole-2-amine derivatives and their subsequent optimization, guided by structure-based design, to give 8-(1H-pyrazol-3-yl)pyrido[3,4-d]pyrimidin-4(3H)-ones, a series of potent JmjC histone N-methyl lysine demethylase (KDM) inhibitors which bind to Fe(II) in the active site. Substitution from C4 of the pyrazole moiety allows access to the histone peptide substrate binding site; incorporation of a conformationally constrained 4-phenylpiperidine linker gives derivatives such as 54j and 54k which demonstrate equipotent activity versus the KDM4 (JMJD2) and KDM5 (JARID1) subfamily demethylases, selectivity over representative exemplars of the KDM2, KDM3, and KDM6 subfamilies, cellular permeability in the Caco-2 assay, and, for 54k, inhibition of H3K9Me3 and H3K4Me3 demethylation in a cell-based assay.

  4. 3-(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-alkyl-N-arylbenzamides: potent, non-peptidic agonists of both the micro and delta opioid receptors.

    Science.gov (United States)

    Bishop, Michael J; Garrido, Dulce M; Boswell, G Evan; Collins, Mark A; Harris, Philip A; McNutt, Robert W; O'Neill, Scott J; Wei, Ke; Chang, Kwen-Jen

    2003-02-13

    Opioid analgesics with both micro and delta opioid receptor activation represent a new approach to the treatment of severe pain with an improved safety profile. Compounds with this profile may exhibit strong analgesic properties due to micro agonism, with a reduced side effect profile resulting from delta agonism. Replacing the p-diethylamide of the known potent delta opioid receptor selective agonist BW373U86 with a m-diethylamide resulted in a compound with agonist activity at both the micro and delta opioid receptors. Modifying the amide to an N-methyl-N-phenylamide increased agonist potency at both receptors. A series of 3-(alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-alkyl-N-arylbenzamides have been made to explore the structure-activity relationship (SAR) around the N-methyl-N-phenylamide. Several potent agonists of both the micro and delta opioid receptors have been identified, including (+)-3-((alphaR)-alpha-((2S,5R)-4-allyl-2,5-dimethyl-1-piperazinyl)-3-hydroxybenzyl)-N-(4-fluorophenyl)-N-methylbenzamide (23), which has EC50 values of 0.67 and 1.1 nM at the micro (guinea pig ileum assay) and delta (mouse vas deferens assay) opioid receptors, respectively.

  5. [Non-peptide furin inhibitors based on amidinohydrazones of diarylaldehydes].

    Science.gov (United States)

    Kibirev, V K; Osadchuk, T V; Kozachenko, A P; Vadziuk, O B; Brovarets, V S

    2013-01-01

    A series of novel non-peptidic furin inhibitors containing amidinohydrazone moieties has been synthesized under interaction of dialdehydes, the derivatives of ethylene diethylvanillin ethers, with aminoguanidine bicarbonate. Two aryl cycles were bridged by 1,2-ethylene-, 1,4-buthylene- or 1,4-dimethylenebenzene-group. The compounds have been found to inhibit furin. The antifurin activity was shown to grow with the increase of the length and/or hydrophobicity of the bridge. The most potent compound, containing in the bridge the lypophylic benzene cycle was found to inhibit the activity of furin with Ki = 0.51 microM.

  6. Cell-permeable and plasma-stable peptidomimetic inhibitors of the postsynaptic density-95/N-methyl-D-aspartate receptor interaction

    DEFF Research Database (Denmark)

    Bach, Anders*; Eildal, Jonas Nii Nortey*; Stuhr-Hansen, Nicolai

    2011-01-01

    The protein--protein interaction between the NMDA receptor and its intracellular scaffolding protein, PSD-95, is a potential target for treating ischemic brain diseases, neuropathic pain, and Alzheimer's disease. We have previously demonstrated that N-alkylated tetrapeptides are potent inhibitors...... to identification of N-cyclohexylethyl-ETA(S)V (54) as the most potent, plasma-stable and cell-permeable inhibitor, which is a promising tool in unraveling the therapeutic potential of the PSD-95/NMDA receptor interaction....

  7. 4-Quinolone-3-carboxylic acids as cell-permeable inhibitors of protein tyrosine phosphatase 1B.

    Science.gov (United States)

    Zhi, Ying; Gao, Li-Xin; Jin, Yi; Tang, Chun-Lan; Li, Jing-Ya; Li, Jia; Long, Ya-Qiu

    2014-07-15

    Protein tyrosine phosphatase 1B is a negative regulator in the insulin and leptin signaling pathways, and has emerged as an attractive target for the treatment of type 2 diabetes and obesity. However, the essential pharmacophore of charged phosphotyrosine or its mimetic confer low selectivity and poor cell permeability. Starting from our previously reported aryl diketoacid-based PTP1B inhibitors, a drug-like scaffold of 4-quinolone-3-carboxylic acid was introduced for the first time as a novel surrogate of phosphotyrosine. An optimal combination of hydrophobic groups installed at C-6, N-1 and C-3 positions of the quinolone motif afforded potent PTP1B inhibitors with low micromolar IC50 values. These 4-quinolone-3-carboxylate based PTP1B inhibitors displayed a 2-10 fold selectivity over a panel of PTP's. Furthermore, the bidentate inhibitors of 4-quinolone-3-carboxylic acids conjugated with aryl diketoacid or salicylic acid were cell permeable and enhanced insulin signaling in CHO/hIR cells. The kinetic studies and molecular modeling suggest that the 4-quinolone-3-carboxylates act as competitive inhibitors by binding to the PTP1B active site in the WPD loop closed conformation. Taken together, our study shows that the 4-quinolone-3-carboxylic acid derivatives exhibit improved pharmacological properties over previously described PTB1B inhibitors and warrant further preclinical studies.

  8. Non-peptide metabolites from the genus Bacillus.

    Science.gov (United States)

    Hamdache, Ahlem; Lamarti, Ahmed; Aleu, Josefina; Collado, Isidro G

    2011-04-25

    Bacillus species produce a number of non-peptide metabolites that display a broad spectrum of activity and structurally diverse bioactive chemical structures. Biosynthetic, biological, and structural studies of these metabolites isolated from Bacillus species are reviewed. This contribution also includes a detailed study of the activity of the metabolites described, especially their role in biological control mechanisms.

  9. A Novel Non-Peptidic Agonist of the Ghrelin Receptor with Orexigenic Activity In vivo

    Science.gov (United States)

    Pastor-Cavada, Elena; Pardo, Leticia M.; Kandil, Dalia; Torres-Fuentes, Cristina; Clarke, Sarah L.; Shaban, Hamdy; McGlacken, Gerard P.; Schellekens, Harriet

    2016-11-01

    Loss of appetite in the medically ill and ageing populations is a major health problem and a significant symptom in cachexia syndromes, which is the loss of muscle and fat mass. Ghrelin is a gut-derived hormone which can stimulate appetite. Herein we describe a novel, simple, non-peptidic, 2-pyridone which acts as a selective agonist for the ghrelin receptor (GHS-R1a). The small 2-pyridone demonstrated clear agonistic activity in both transfected human cells and mouse hypothalamic cells with endogenous GHS-R1a receptor expression. In vivo tests with the hit compound showed significant increased food intake following peripheral administration, which highlights the potent orexigenic effect of this novel GHS-R1a receptor ligand.

  10. Colon-targeted cell-permeable NFκB inhibitory peptide is orally active against experimental colitis.

    Science.gov (United States)

    Hong, Sungchae; Yum, Soohwan; Yoo, Hyun-Jung; Kang, Sookjin; Yoon, Jeong-Hyun; Min, Dosik; Kim, Young Mi; Jung, Yunjin

    2012-05-07

    For the purpose of development of orally active peptide therapeutics targeting NFκB for treatment of inflammatory bowel disease (IBD), two major barriers in oral delivery of therapeutic peptides, metabolic lability and tissue impermeability, were circumvented by introduction of a colon-targeted delivery system and cell permeable peptides (CPP) to NFκB inhibitory peptides (NIP). Suppression of NFκB activation was compared following treatment with various CPP conjugated NIPs (CPP-NIP). The most potent CPP-NIP was loaded in a capsule coated with a colon specific polymer, which was administered orally to colitic rats. The anti-inflammatory activity of the colon-targeted CPP-NIP was evaluated by measuring inflammatory indices in the inflamed colonic tissue. For confirmation of the local action of the CPP-NIP, the same experiment was done after rectal administration. Tissue permeability of the CPP-NIP was examined microscopically and spectrophotometrically using FITC-labeled CPP-NIP (CPP-NIP-FITC). NEMO binding domain peptide (NBD, TALDWSWLQTE) fused with a cell permeable peptide CTP (YGRRARRRARR), CTP-NBD, was most potent in inhibiting NFκB activity in cells. Colon-targeted CTP-NBD, but not colon-targeted NBD and CTP-NBD in an enteric capsule, ameliorated the colonic injury, which was in parallel with decrease in MPO activity and the levels of inflammatory mediators. Intracolonic treatment with CTP-NBD alleviated rat colitis and improved all the inflammatory indicators. CTP-NBD-FITC was detected at much greater level in the inflamed tissue than was NBD-FITC. Taken together, introduction of cell permeability and colon targetability to NIP may be a feasible strategy for an orally active peptide therapy for treatment of IBD.

  11. Cell Permeable Ratiometric Fluorescent Sensors for Imaging Phosphoinositides.

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    Mondal, Samsuzzoha; Rakshit, Ananya; Pal, Suranjana; Datta, Ankona

    2016-07-15

    Phosphoinositides are critical cell-signal mediators present on the plasma membrane. The dynamic change of phosphoinositide concentrations on the membrane including clustering and declustering mediates signal transduction. The importance of phosphoinositides is scored by the fact that they participate in almost all cell-signaling events, and a defect in phosphoinositide metabolism is linked to multiple diseases including cancer, bipolar disorder, and type-2 diabetes. Optical sensors for visualizing phosphoinositide distribution can provide information on phosphoinositide dynamics. This exercise will ultimately afford a handle into understanding and manipulating cell-signaling processes. The major requirement in phosphoinositide sensor development is a selective, cell permeable probe that can quantify phosphoinositides. To address this requirement, we have developed short peptide-based ratiometric fluorescent sensors for imaging phosphoinositides. The sensors afford a selective response toward two crucial signaling phosphoinositides, phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) and phosphatidylinositol-4-phosphate (PI4P), over other anionic membrane phospholipids and soluble inositol phosphates. Dissociation constant values indicate up to 4 times higher probe affinity toward PI(4,5)P2 when compared to PI4P. Significantly, the sensors are readily cell-permeable and enter cells within 15 min of incubation as indicated by multiphoton excitation confocal microscopy. Furthermore, the sensors light up signaling phosphoinositides present both on the cell membrane and on organelle membranes near the perinuclear space, opening avenues for quantifying and monitoring phosphoinositide signaling.

  12. Diethylentriaminepenta acetic acid glucose conjugates as a cell permeable iron chelator

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    Mona Mosayebnia

    2014-01-01

    Full Text Available Objective: To find out whether DTPA-DG complex can enhance clearance of intracellular free iron. Materials and Methods: Diethylenetriaminepentaacetic acid-D-deoxy-glucosamine (DTPA-DG was synthesized and examined for its activity as a cell-permeable iron chelator in human hepatocellular carcinoma (HEPG2 cell line exposed to high concentration of iron sulfate and compared with deferoxamine (DFO, a prototype iron chelator. The effect of DTPA-DG on cell viability was monitored using the 3-(4,5-dimethythiazol-2-yl-2,5-diphenyl tetrazolium bromide MTT assay as well. Results: There was a significant increase of iron level after iron overload induction in HEPG2 cell culture. DTPA-DG presented a remarkable capacity to iron burden reducing with estimated 50% inhibitory concentration value of 65.77 nM. In fact, glycosyl moiety was gained access of DTPA to intracellular iron deposits through glucose transporter systems. Conclusion: DTPA-DG, more potent than DFO to sequester deposits of free iron with no profound toxic effect. The results suggest the potential of DTPA-DG in chelating iron and permitting its excretion from primary organ storage.

  13. Chemotaxis of human and rat leukocytes by the delta-selective non-peptidic opioid SNC 80.

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    Ordaz-Sánchez, Iván; Weber, Richard J; Rice, Kenner C; Zhang, Xiaoyan; Rodríguez-Padilla, C; Tamez-Guerra, R; Méndez-Vázquez, José L; Gómez-Flores, R

    2003-01-01

    Opioids like morphine, represent a major source of relief for most chronic moderate to severe nonmalignant pain. However, opioid abuse may lead to infections such as hepatitis and AIDS because opioids have been associated with suppressing various parameters of immune function including antimicrobial resistance, antibody production, monocyte-mediated phagocytosis, and both neutrophil and monocyte chemotaxis. We have previously reported immunopotentiating properties of non-peptidic opioid receptor selective agonists and antagonists. In this study, we evaluated the effects of the nonpeptidic delta-opioid receptor agonist (+)-4-((alpha R)-alpha-((2S, 5R)-4-allyl-2, 5-dimethyl-1-piperazinyl)-3-methoxybenzyl)-N, N-diethyl-benzamide (SNC 80) on chemotaxis of rat thymic and human peripheral blood mononuclear cells by using a modified Wilkinson chamber. Cell recruitment is an essential process in acute and chronic inflammatory responses. We observed that SNC 80 at concentrations of 10(-10), 10(-9), 10(-8), 10(-7), and 10(-6) M, significantly (p SNC 80 on chemotaxis of rat and human leukocytes were antagonized by naloxone, indicating that the modulation of chemotaxis by SNC 80 is via a classic opioid receptor. The development and use of non-peptidic opioids like SNC 80 could have an immediate impact not only as potent analgesics, but in immunoregulation.

  14. A cell-permeable fluorescent polymeric thermometer for intracellular temperature mapping in mammalian cell lines.

    Directory of Open Access Journals (Sweden)

    Teruyuki Hayashi

    Full Text Available Changes in intracellular temperatures reflect the activity of the cell. Thus, the tool to measure intracellular temperatures could provide valuable information about cellular status. We previously reported a method to analyze the intracellular temperature distribution using a fluorescent polymeric thermometer (FPT in combination with fluorescence lifetime imaging microscopy (FLIM. Intracellular delivery of the FPT used in the previous study required microinjection. We now report a novel FPT that is cell permeable and highly photostable, and we describe the application of this FPT to the imaging of intracellular temperature distributions in various types of mammalian cell lines. This cell-permeable FPT displayed a temperature resolution of 0.05°C to 0.54°C within the range from 28°C to 38°C in HeLa cell extracts. Using our optimized protocol, this cell-permeable FPT spontaneously diffused into HeLa cells within 10 min of incubation and exhibited minimal toxicity over several hours of observation. FLIM analysis confirmed a temperature difference between the nucleus and the cytoplasm and heat production near the mitochondria, which were also detected previously using the microinjected FPT. We also showed that this cell-permeable FPT protocol can be applied to other mammalian cell lines, COS7 and NIH/3T3 cells. Thus, this cell-permeable FPT represents a promising tool to study cellular states and functions with respect to temperature.

  15. A cell-permeable fluorescent polymeric thermometer for intracellular temperature mapping in mammalian cell lines.

    Science.gov (United States)

    Hayashi, Teruyuki; Fukuda, Nanaho; Uchiyama, Seiichi; Inada, Noriko

    2015-01-01

    Changes in intracellular temperatures reflect the activity of the cell. Thus, the tool to measure intracellular temperatures could provide valuable information about cellular status. We previously reported a method to analyze the intracellular temperature distribution using a fluorescent polymeric thermometer (FPT) in combination with fluorescence lifetime imaging microscopy (FLIM). Intracellular delivery of the FPT used in the previous study required microinjection. We now report a novel FPT that is cell permeable and highly photostable, and we describe the application of this FPT to the imaging of intracellular temperature distributions in various types of mammalian cell lines. This cell-permeable FPT displayed a temperature resolution of 0.05°C to 0.54°C within the range from 28°C to 38°C in HeLa cell extracts. Using our optimized protocol, this cell-permeable FPT spontaneously diffused into HeLa cells within 10 min of incubation and exhibited minimal toxicity over several hours of observation. FLIM analysis confirmed a temperature difference between the nucleus and the cytoplasm and heat production near the mitochondria, which were also detected previously using the microinjected FPT. We also showed that this cell-permeable FPT protocol can be applied to other mammalian cell lines, COS7 and NIH/3T3 cells. Thus, this cell-permeable FPT represents a promising tool to study cellular states and functions with respect to temperature.

  16. Discovery and Characterization of a Cell-Permeable, Small-Molecule c-Abl Kinase Activator that Binds to the Myristoyl Binding Site

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Jingsong; Campobasso, Nino; Biju, Mangatt P.; Fisher, Kelly; Pan, Xiao-Qing; Cottom, Josh; Galbraith, Sarah; Ho, Thau; Zhang, Hong; Hong, Xuan; Ward, Paris; Hofmann, Glenn; Siegfried, Brett; Zappacosta, Francesca; Washio, Yoshiaki; Cao, Ping; Qu, Junya; Bertrand, Sophie; Wang, Da-Yuan; Head, Martha S.; Li, Hu; Moores, Sheri; Lai, Zhihong; Johanson, Kyung; Burton, George; Erickson-Miller, Connie; Simpson, Graham; Tummino, Peter; Copeland, Robert A.; Oliff, Allen (GSKPA)

    2014-10-02

    c-Abl kinase activity is regulated by a unique mechanism involving the formation of an autoinhibited conformation in which the N-terminal myristoyl group binds intramolecularly to the myristoyl binding site on the kinase domain and induces the bending of the {alpha}I helix that creates a docking surface for the SH2 domain. Here, we report a small-molecule c-Abl activator, DPH, that displays potent enzymatic and cellular activity in stimulating c-Abl activation. Structural analyses indicate that DPH binds to the myristoyl binding site and prevents the formation of the bent conformation of the {alpha}I helix through steric hindrance, a mode of action distinct from the previously identified allosteric c-Abl inhibitor, GNF-2, that also binds to the myristoyl binding site. DPH represents the first cell-permeable, small-molecule tool compound for c-Abl activation.

  17. Cell-permeable nanobodies for targeted immunolabelling and antigen manipulation in living cells

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    Herce, Henry D.; Schumacher, Dominik; Schneider, Anselm F. L.; Ludwig, Anne K.; Mann, Florian A.; Fillies, Marion; Kasper, Marc-André; Reinke, Stefan; Krause, Eberhard; Leonhardt, Heinrich; Cardoso, M. Cristina; Hackenberger, Christian P. R.

    2017-08-01

    Functional antibody delivery in living cells would enable the labelling and manipulation of intracellular antigens, which constitutes a long-thought goal in cell biology and medicine. Here we present a modular strategy to create functional cell-permeable nanobodies capable of targeted labelling and manipulation of intracellular antigens in living cells. The cell-permeable nanobodies are formed by the site-specific attachment of intracellularly stable (or cleavable) cyclic arginine-rich cell-penetrating peptides to camelid-derived single-chain VHH antibody fragments. We used this strategy for the non-endocytic delivery of two recombinant nanobodies into living cells, which enabled the relocalization of the polymerase clamp PCNA (proliferating cell nuclear antigen) and tumour suppressor p53 to the nucleolus, and thereby allowed the detection of protein-protein interactions that involve these two proteins in living cells. Furthermore, cell-permeable nanobodies permitted the co-transport of therapeutically relevant proteins, such as Mecp2, into the cells. This technology constitutes a major step in the labelling, delivery and targeted manipulation of intracellular antigens. Ultimately, this approach opens the door towards immunostaining in living cells and the expansion of immunotherapies to intracellular antigen targets.

  18. Interaction of a non-peptide agonist with angiotensin II AT1 receptor mutants

    DEFF Research Database (Denmark)

    Costa-Neto, Claudio M; Miyakawa, Ayumi A; Pesquero, João B;

    2002-01-01

    To identify residues of the rat AT1A angiotensin II receptor involved with signal transduction and binding of the non-peptide agonist L-162,313 (5,7-dimethyl-2-ethyl-3-[[4-[2(n-butyloxycarbonylsulfonamido)-5-isobutyl-3-thienyl]phenyl]methyl]imidazol[4,5,6]-pyridine) we have performed ligand bindi...

  19. Discovery and cardioprotective effects of the first non-Peptide agonists of the G protein-coupled prokineticin receptor-1.

    Directory of Open Access Journals (Sweden)

    Adeline Gasser

    Full Text Available Prokineticins are angiogenic hormones that activate two G protein-coupled receptors: PKR1 and PKR2. PKR1 has emerged as a critical mediator of cardiovascular homeostasis and cardioprotection. Identification of non-peptide PKR1 agonists that contribute to myocardial repair and collateral vessel growth hold promises for treatment of heart diseases. Through a combination of in silico studies, medicinal chemistry, and pharmacological profiling approaches, we designed, synthesized, and characterized the first PKR1 agonists, demonstrating their cardioprotective activity against myocardial infarction (MI in mice. Based on high throughput docking protocol, 250,000 compounds were computationally screened for putative PKR1 agonistic activity, using a homology model, and 10 virtual hits were pharmacologically evaluated. One hit internalizes PKR1, increases calcium release and activates ERK and Akt kinases. Among the 30 derivatives of the hit compound, the most potent derivative, IS20, was confirmed for its selectivity and specificity through genetic gain- and loss-of-function of PKR1. Importantly, IS20 prevented cardiac lesion formation and improved cardiac function after MI in mice, promoting proliferation of cardiac progenitor cells and neovasculogenesis. The preclinical investigation of the first PKR1 agonists provides a novel approach to promote cardiac neovasculogenesis after MI.

  20. Rational design and identification of a non-peptidic aggregation inhibitor of amyloid-β based on a pharmacophore motif obtained from cyclo[-Lys-Leu-Val-Phe-Phe-].

    Science.gov (United States)

    Arai, Tadamasa; Araya, Takushi; Sasaki, Daisuke; Taniguchi, Atsuhiko; Sato, Takeshi; Sohma, Youhei; Kanai, Motomu

    2014-07-28

    Inhibition of pathogenic protein aggregation may be an important and straightforward therapeutic strategy for curing amyloid diseases. Small-molecule aggregation inhibitors of Alzheimer's amyloid-β (Aβ) are extremely scarce, however, and are mainly restricted to dye- and polyphenol-type compounds that lack drug-likeness. Based on the structure-activity relationship of cyclic Aβ16-20 (cyclo-[KLVFF]), we identified unique pharmacophore motifs comprising side-chains of Leu(2), Val(3), Phe(4), and Phe(5) residues without involvement of the backbone amide bonds to inhibit Aβ aggregation. This finding allowed us to design non-peptidic, small-molecule aggregation inhibitors that possess potent activity. These molecules are the first successful non-peptidic, small-molecule aggregation inhibitors of amyloids based on rational molecular design.

  1. Computational Studies of Difference in Binding Modes of Peptide and Non-Peptide Inhibitors to MDM2/MDMX Based on Molecular Dynamics Simulations

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    Yuxin Zhang

    2012-02-01

    Full Text Available Inhibition of p53-MDM2/MDMX interaction is considered to be a promising strategy for anticancer drug design to activate wild-type p53 in tumors. We carry out molecular dynamics (MD simulations to study the binding mechanisms of peptide and non-peptide inhibitors to MDM2/MDMX. The rank of binding free energies calculated by molecular mechanics generalized Born surface area (MM-GBSA method agrees with one of the experimental values. The results suggest that van der Waals energy drives two kinds of inhibitors to MDM2/MDMX. We also find that the peptide inhibitors can produce more interaction contacts with MDM2/MDMX than the non-peptide inhibitors. Binding mode predictions based on the inhibitor-residue interactions show that the π–π, CH–π and CH–CH interactions dominated by shape complimentarity, govern the binding of the inhibitors in the hydrophobic cleft of MDM2/MDMX. Our studies confirm the residue Tyr99 in MDMX can generate a steric clash with the inhibitors due to energy and structure. This finding may theoretically provide help to develop potent dual-specific or MDMX inhibitors.

  2. Discovery of 1-[4-(N-benzylamino)phenyl]-3-phenylurea derivatives as non-peptidic selective SUMO-sentrin specific protease (SENP)1 inhibitors.

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    Uno, Masaharu; Koma, Yosuke; Ban, Hyun Seung; Nakamura, Hiroyuki

    2012-08-15

    We developed 1-[4-(N-benzylamino)phenyl]-3-phenylurea derivative 4 (GN6958) as a non-peptidic selective SUMO-sentrin specific protease (SENP)1 protease inhibitor based on the hypoxia inducible factor (HIF)-1α inhibitor 1 (GN6767). The direct interaction of compound 1 with SENP1 protein in cells was observed by the pull-down experiments using the biotin-tagged compound 2 coated on the streptavidin affinity column. Among the various 1-[4-(N-benzylamino)phenyl]-3-phenylurea derivatives tested, compounds 3 and 4 suppressed HIF-1α accumulation in a concentration-dependent manner without affecting the expression level of tubulin protein in HeLa cells. Both compounds inhibited SENP1 protease activity in a concentration-dependent manner, and compound 4 exhibited more potent inhibition than compound 3. Compound 4 exhibited selective inhibition against SENP1 protease activity without inhibiting other protease enzyme activities in vitro.

  3. Rescue From Lethal Shiga Toxin 2-induced Renal Failure With A Cell-Permeable Peptide

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    Stearns-Kurosawa, Deborah J.; Collins, Valta; Freeman, Scott; Debord, Diann; Nishikawa, Kiyotaka; Oh, Sun-Young; Leibowitz, Caitlin S.; Kurosawa, Shinichiro

    2011-01-01

    Background Intestinal infection with Shiga toxin (Stx)-producing E.coli is a leading cause of hemolytic uremic syndrome and acute renal injury in otherwise healthy children in the US. Antibiotics are contraindicated and a therapeutic priority is agents that act intracellularly against the bacterial toxins which drive kidney injury. Our aim was to evaluate whether intravenous administration of a cell-permeable peptide (TVP) that binds to Stx2 will reduce disease severity and rescue juvenile baboons from a lethal Stx2 dose (50ng/kg). Methods TVP (5mg/kg) was delivered i.v. simultaneously with toxin (prevention protocol) or at 6 or 24 hours after toxin with daily 1mg/kg supplements up to Day 4 (rescue protocols). Biomarkers were monitored in blood and urine up to 28 days. Results and Conclusions TVP therapy resulted in either absence of clinical signs of acute kidney injury and normal urine output (prevention), or delayed and reduced BUN and creatinine levels (rescue) with concomitant survival. Delayed peptide administration significantly reduced thrombocytopenia, but surprisingly did not alter anemia even when monitored for 28 days in rescued survivors. This is the first successful cell-permeable therapeutic that counteracts Stx2 lethality in an animal model which recapitulates many of the human responses to enteric infection. PMID:21603905

  4. A structural feature of the non-peptide ligand interactions with mice mu-opioid receptors.

    Science.gov (United States)

    Noori, Hamid R; Mucksch, Christian; Urbassek, Herbert M

    2014-01-01

    By binding to and activating the G-protein coupled μ-, κ- and δ-opioid receptors in the central nervous system, opiates are known to induce analgesic and sedative effects. In particular, non-peptide opioid ligands are often used in clinical applications to induce these therapeutically beneficial effects, due to their superior pharmacokinetics and bioavailability in comparison to endogenous neuropeptides. However, since opioid alkaloids are highly addictive substances, it is necessary to understand the exact mechanisms of their actions, specifically the ligand-binding properties of the target receptors, in order to safely apply opiates for therapeutic purposes. Using an in silico molecular docking approach (AutoDock Vina) combined with two-step cluster analysis, we have computationally obtained the docking scores and the ligand-binding pockets of twelve representative non-peptide nonendogenous agonists and antagonists at the crystallographically identified μ-opioid receptor. Our study predicts the existence of two main binding sites that are congruently present in all opioid receptor types. Interestingly, in terms of the agonist or antagonist properties of the substances on the receptors, the clustering analysis suggests a relationship with the position of the ligand-binding pockets, particularly its depth within the receptor structure. Furthermore, the binding affinity of the substances is directly correlated to the proximity of the binding pockets to the extracellular space. In conclusion, the results provide further insights into the structural features of the functional pharmacology of opioid receptors, suggesting the importance of the binding position of non-peptide agonists and antagonists- specifically the distance and the level of exposure to the extracellular space- to their dissociation kinetics and subsequent potency.

  5. Non-Peptide-based Small-Molecule Probe for Fluorogenic and Chromogenic Detection of Chymotrypsin.

    Science.gov (United States)

    Wu, Lei; Yang, Shu-Hou; Xiong, Hao; Yang, Jia-Qian; Guo, Jun; Yang, Wen-Chao; Yang, Guang-Fu

    2017-02-23

    We report herein a non-peptide-based small molecule probe for fluorogenic and chromogenic detection of chymotrypsin, and the primary application. This probe was rationally designed by mimicking the peptide substrate and optimized by adjusting the recognization group. The refined probe 2 exhibits good specificity toward chymotrypsin, producing about 25-fold higher enhancement in both the fluorescence intensity and absorbance upon the catalysis by chymotrypsin. Compared with the most widely used peptide substrate (AMC-FPAA-Suc) of chymotrypsin, probe 2 shows about 5-fold higher binding affinity, and comparable catalytical efficiency against chymotrypsin. Furthermore, it was successfully applied for the inhibitor characterization. To the best of our knowledge, probe 2 is the first non-peptide-based small-molecule probe for chymotrypsin, with the advantages of simple structure and high sensitivity compared to the widely used peptide-based substrates. This small-molecule probe is expected to be a useful molecular tool for drug discovery and chymotrypsin-related diseases diagnosis.

  6. Iron oxide nanoparticles induce human microvascular endothelial cell permeability through reactive oxygen species production and microtubule remodeling

    Directory of Open Access Journals (Sweden)

    Shi Xianglin

    2009-01-01

    Full Text Available Abstract Background Engineered iron nanoparticles are being explored for the development of biomedical applications and many other industry purposes. However, to date little is known concerning the precise mechanisms of translocation of iron nanoparticles into targeted tissues and organs from blood circulation, as well as the underlying implications of potential harmful health effects in human. Results The confocal microscopy imaging analysis demonstrates that exposure to engineered iron nanoparticles induces an increase in cell permeability in human microvascular endothelial cells. Our studies further reveal iron nanoparticles enhance the permeability through the production of reactive oxygen species (ROS and the stabilization of microtubules. We also showed Akt/GSK-3β signaling pathways are involved in iron nanoparticle-induced cell permeability. The inhibition of ROS demonstrate ROS play a major role in regulating Akt/GSK-3β – mediated cell permeability upon iron nanoparticle exposure. These results provide new insights into the bioreactivity of engineered iron nanoparticles which can inform potential applications in medical imaging or drug delivery. Conclusion Our results indicate that exposure to iron nanoparticles induces an increase in endothelial cell permeability through ROS oxidative stress-modulated microtubule remodeling. The findings from this study provide new understandings on the effects of nanoparticles on vascular transport of macromolecules and drugs.

  7. A PCNA-derived cell permeable peptide selectively inhibits neuroblastoma cell growth.

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    Long Gu

    Full Text Available Proliferating cell nuclear antigen (PCNA, through its interaction with various proteins involved in DNA synthesis, cell cycle regulation, and DNA repair, plays a central role in maintaining genome stability. We previously reported a novel cancer associated PCNA isoform (dubbed caPCNA, which was significantly expressed in a broad range of cancer cells and tumor tissues, but not in non-malignant cells. We found that the caPCNA-specific antigenic site lies between L126 and Y133, a region within the interconnector domain of PCNA that is known to be a major binding site for many of PCNA's interacting proteins. We hypothesized that therapeutic agents targeting protein-protein interactions mediated through this region may confer differential toxicity to normal and malignant cells. To test this hypothesis, we designed a cell permeable peptide containing the PCNA L126-Y133 sequence. Here, we report that this peptide selectively kills human neuroblastoma cells, especially those with MYCN gene amplification, with much less toxicity to non-malignant human cells. Mechanistically, the peptide is able to block PCNA interactions in cancer cells. It interferes with DNA synthesis and homologous recombination-mediated double-stranded DNA break repair, resulting in S-phase arrest, accumulation of DNA damage, and enhanced sensitivity to cisplatin. These results demonstrate conceptually the utility of this peptide for treating neuroblastomas, particularly, the unfavorable MYCN-amplified tumors.

  8. GluVII:06--a highly conserved and selective anchor point for non-peptide ligands in chemokine receptors

    DEFF Research Database (Denmark)

    Rosenkilde, Mette M; Schwartz, Thue W

    2006-01-01

    to be crucially important for the binding and action of a number of non-peptide ligands in for example the CCR1, CCR2 and CCR5 receptors. It is proposed that in chemokine receptors in general GluVII:06 serves as a selective anchor point for the centrally located, positively charged nitrogen of the small molecule...

  9. The non-peptidic part determines the internalization mechanism and intracellular trafficking of peptide amphiphiles.

    Directory of Open Access Journals (Sweden)

    Dimitris Missirlis

    Full Text Available BACKGROUND: Peptide amphiphiles (PAs are a class of amphiphilic molecules able to self-assemble into nanomaterials that have shown efficient in vivo targeted delivery. Understanding the interactions of PAs with cells and the mechanisms of their internalization and intracellular trafficking is critical in their further development for therapeutic delivery applications. METHODOLOGY/PRINCIPAL FINDINGS: PAs of a novel, cell- and tissue-penetrating peptide were synthesized possessing two different lipophilic tail architectures and their interactions with prostate cancer cells were studied in vitro. Cell uptake of peptides was greatly enhanced post-modification. Internalization occurred via lipid-raft mediated endocytosis and was common for the two analogs studied. On the contrary, we identified the non-peptidic part as the determining factor of differences between intracellular trafficking and retention of PAs. PAs composed of di-stearyl lipid tails linked through poly(ethylene glycol to the peptide exhibited higher exocytosis rates and employed different recycling pathways compared to ones consisting of di-palmitic-coupled peptides. As a result, cell association of the former PAs decreased with time. CONCLUSIONS/SIGNIFICANCE: Control over peptide intracellular localization and retention is possible by appropriate modification with synthetic hydrophobic tails. We propose this as a strategy to design improved peptide-based delivery systems.

  10. AVE 0991, a non-peptide Mas-receptor agonist, facilitates penile erection.

    Science.gov (United States)

    da Costa Gonçalves, Andrey C; Fraga-Silva, Rodrigo A; Leite, Romulo; Santos, Robson A S

    2013-03-01

    The renin-angiotensin system plays a crucial role in erectile function. It has been shown that elevated levels of angiotensin II contribute to the development of erectile dysfunction both in humans and in aminals. On the contrary, the heptapeptide angiotensin-(1-7) appears to mediate penile erection by activation of the Mas receptor. Recently, we have shown that the erectile function of Mas gene-deleted mice was substantially reduced, which was associated with a marked increase in fibrous tissue in the corpus cavernosum. We have hypothesized that the synthetic non-peptide Mas agonist, AVE 0991, would potentiate penile erectile function. We showed that intracavernosal injection of AVE 0991 potentiated the erectile response of anaesthetized Wistar rats, measured as the ratio between corpus cavernosum pressure and mean arterial pressure, upon electrical stimulation of the major pelvic ganglion. The facilitatory effect of AVE 0991 on erectile function was dose dependent and completely blunted by the nitric oxide synthesis inhibitor, l-NAME. Importantly, concomitant intracavernosal infusion of the specific Mas receptor blocker, A-779, abolished the effect of AVE 0991. We demonstrated that AVE 0991 potentiates the penile erectile response through Mas in an NO-dependent manner. Importantly, these results suggest that Mas agonists, such as AVE 0991, might have significant therapeutic benefits for the treatment of erectile dysfunction.

  11. Small molecule, non-peptide p75 ligands inhibit Abeta-induced neurodegeneration and synaptic impairment.

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    Tao Yang

    Full Text Available The p75 neurotrophin receptor (p75(NTR is expressed by neurons particularly vulnerable in Alzheimer's disease (AD. We tested the hypothesis that non-peptide, small molecule p75(NTR ligands found to promote survival signaling might prevent Abeta-induced degeneration and synaptic dysfunction. These ligands inhibited Abeta-induced neuritic dystrophy, death of cultured neurons and Abeta-induced death of pyramidal neurons in hippocampal slice cultures. Moreover, ligands inhibited Abeta-induced activation of molecules involved in AD pathology including calpain/cdk5, GSK3beta and c-Jun, and tau phosphorylation, and prevented Abeta-induced inactivation of AKT and CREB. Finally, a p75(NTR ligand blocked Abeta-induced hippocampal LTP impairment. These studies support an extensive intersection between p75(NTR signaling and Abeta pathogenic mechanisms, and introduce a class of specific small molecule ligands with the unique ability to block multiple fundamental AD-related signaling pathways, reverse synaptic impairment and inhibit Abeta-induced neuronal dystrophy and death.

  12. AT2 receptor non-peptide agonist C21 promotes natriuresis in obese Zucker rats.

    Science.gov (United States)

    Ali, Quaisar; Hussain, Tahir

    2012-06-01

    Previously, we demonstrated that angiotensin II type 2 (AT(2)) receptors have a role in natriuresis in obese Zucker rats (OZR). In the present study, we investigated the role of a novel, non-peptide agonist, C21, in natriuresis via AT(2) receptor activation in OZR. Infusion of C21 (1 and 5 μg kg(-1) min(-1)) into rats under anesthesia caused a dose-dependent increase in urine flow (UF) and urinary Na volume (U(Na)V). These effects of C21 were blocked by pre-infusion of the AT(2) receptor antagonist, PD123319, (50 μg kg(-1) min(-1)), suggesting involvement of the AT(2) receptor. Infusion of C21 (5 μg kg(-1) min(-1)) significantly increased the fractional excretion of sodium without changing the glomerular filtration rate or blood pressure, suggesting a tubular effect. Similarly, C21 infusion increased the fractional excretion of lithium, suggesting a proximal tubular effect. Furthermore, we tested the effect of C21 on natriuresis after blocking two main, distal-nephron Na transporters, the epithelial Na channels (ENaC), with amiloride (AM, 3 mg kg(-1) body wt), and the NaCl cotransporters (NCC), with bendroflumethiazide (BFTZ, 7 mg kg(-1) body wt). Infusion of AM + BFTZ caused significant increases in both diuresis and natriuresis, which were further increased by infusion of C21 (5 μg kg(-1) min(-1)). Natriuresis in response to C21 was associated with increases in urinary NO and cGMP levels. The data indicate that the AT(2) receptor agonist, C21, promotes natriuresis via AT(2) receptor activation and that this effect is potentially based in the proximal tubules and linked to the nitric oxide/cyclic guanosine monophosphate pathway. The natriuretic response to C21 may have therapeutic significance by improving kidney function in obesity.

  13. Cytotoxic effect of a non-peptidic small molecular inhibitor of the p53-HDM2 interaction on tumor cells

    Institute of Scientific and Technical Information of China (English)

    Wen-Dong Li; Mi-Juan Wang; Fang Ding; Da-Li Yin; Zhi-Hua Liu

    2005-01-01

    AIM: To investigate if non-peptidic small molecular inhibitors of the p53-HDM2 interaction could restore p53 function and kill tumor cells.METHODS: A series of non-peptidic small HDM2 inhibitors were designed by computer-aided model and synthesized by chemical method. Syl-155 was one of these inhibitors. Cytotoxic effect of syl-155 on three tumor cell lines with various states of p53, HT1080 (wild-type p53), KYSE510 (mutant p53), MG63 (p53 deficiency) was evaluated by MTT assay, Western blot and flow cytometry.RESULTS: Syl-155 stimulated the accumulation of p53 and p21 protein in HT1080 cells expressing wild-type p53, but not in KYSE510 and MG63 cells. Consequently, syl-155 induced cell cycle arrest and apoptosis in HT1080 cells.CONCLUSION: Non-peptidic small molecular inhibitors of the p53-HDM2 interaction show promise in treatment of tumors expressing wild-type p53.

  14. Cell-permeable p38 MAP kinase promotes migration of adult neural stem/progenitor cells

    Science.gov (United States)

    Hamanoue, Makoto; Morioka, Kazuhito; Ohsawa, Ikuroh; Ohsawa, Keiko; Kobayashi, Masaaki; Tsuburaya, Kayo; Akasaka, Yoshikiyo; Mikami, Tetsuo; Ogata, Toru; Takamatsu, Ken

    2016-01-01

    Endogenous neural stem/progenitor cells (NPCs) can migrate toward sites of injury, but the migration activity of NPCs is insufficient to regenerate damaged brain tissue. In this study, we showed that p38 MAP kinase (p38) is expressed in doublecortin-positive adult NPCs. Experiments using the p38 inhibitor SB203580 revealed that endogenous p38 participates in NPC migration. To enhance NPC migration, we generated a cell-permeable wild-type p38 protein (PTD-p38WT) in which the HIV protein transduction domain (PTD) was fused to the N-terminus of p38. Treatment with PTD-p38WT significantly promoted the random migration of adult NPCs without affecting cell survival or differentiation; this effect depended on the cell permeability and kinase activity of the fusion protein. These findings indicate that PTD-p38WT is a novel and useful tool for unraveling the roles of p38, and that this protein provides a reasonable approach for regenerating the injured brain by enhancing NPC migration. PMID:27067799

  15. The development of non-peptide glucagon-like peptide-1 receptor agonist for the treatment of type 2 diabetes.

    Science.gov (United States)

    Moon, Ho-Sang; Kim, Mi-Kyung; Son, Moon-Ho

    2011-07-01

    Glucagon-like peptide-1 (GLP-1) is the main member of the incretin family and stimulates insulin secretion by binding with its specific receptor on pancreatic β-cells. In addition, GLP-1 exerts broad beneficial effects on the glucose regulation by suppressing food intake and delaying stomach emptying. Now, long acting GLP-1 analogs including exenatide and liraglutide have been approved for the treatment of diabetes mellitus type 2, however long-term injection can limit their use for these chronic patients. In this report, the authors provide a review on the development of non-peptide GLP-1 receptor agonists and introduce a novel agonist DA-15864.

  16. Pro-Cognitive Effects of Non-Peptide Analogues of Soluble Amyloid Peptide Precursor Fragment sAPP.

    Science.gov (United States)

    Tiunova, A A; Komissarova, N V; Nenaidenko, V G; Makhmutova, A A; Beznosko, B K; Bachurin, S O; Anokhin, K V

    2016-08-01

    We studied pro-cognitive effect of two heterocyclic low-molecular-weight compounds that serve as non-peptide analogues of soluble fragment of amyloid peptide precursor (sAPP). Intracerebroventricular and systemic administration of peptide mimetics P2 and P5 improved weak memory on the model of passive avoidance in chicks and in the object location task in mice. Both compounds were effective if administered close to the moment of training or 4 h after it. The time windows and dose range for the pro-cognitive effects of the mimetics were similar to those observed in previous studies with sAPP peptide fragments.

  17. Intracellular protease activation in apoptosis and cell-mediated cytotoxicity characterized by cell-permeable fluorogenic protease substrates

    Institute of Scientific and Technical Information of China (English)

    Beverly Z Packard; Akira Komoriya

    2008-01-01

    Over the past decade the importance of signaling from reporter molecules inside live cells and tissues has been clearly established. Biochemical events related to inflammation, tumor metastasis and proliferation, and viral infectivity and replication are examples of processes being further defined as more molecular tools for live cell measurements become available. Moreover, in addition to quantitating parameters related to physiologic processes, real-time imaging of molecular interactions that compose basic cellular activities are providing insights into understanding disease mechanisms as well as extending clinical efficacy of therapeutic regimens. In this review the use of highly cell-permeable fluorogenic substrates that report protease activities inside live cells is described; applications to defining the molecular events of two cellular processes, i.e., apoptosis and cell-mediated cytotoxicity, are then illustrated.

  18. Endothelial cell permeability during hantavirus infection involves factor XII-dependent increased activation of the kallikrein-kinin system.

    Directory of Open Access Journals (Sweden)

    Shannon L Taylor

    Full Text Available Hemorrhagic fever with renal syndrome (HFRS and hantavirus pulmonary syndrome (HPS are diseases caused by hantavirus infections and are characterized by vascular leakage due to alterations of the endothelial barrier. Hantavirus-infected endothelial cells (EC display no overt cytopathology; consequently, pathogenesis models have focused either on the influx of immune cells and release of cytokines or on increased degradation of the adherens junction protein, vascular endothelial (VE-cadherin, due to hantavirus-mediated hypersensitization of EC to vascular endothelial growth factor (VEGF. To examine endothelial leakage in a relevant in vitro system, we co-cultured endothelial and vascular smooth muscle cells (vSMC to generate capillary blood vessel-like structures. In contrast to results obtained in monolayers of cultured EC, we found that despite viral replication in both cell types as well as the presence of VEGF, infected in vitro vessels neither lost integrity nor displayed evidence of VE-cadherin degradation. Here, we present evidence for a novel mechanism of hantavirus-induced vascular leakage involving activation of the plasma kallikrein-kinin system (KKS. We show that incubation of factor XII (FXII, prekallikrein (PK, and high molecular weight kininogen (HK plasma proteins with hantavirus-infected EC results in increased cleavage of HK, higher enzymatic activities of FXIIa/kallikrein (KAL and increased liberation of bradykinin (BK. Measuring cell permeability in real-time using electric cell-substrate impedance sensing (ECIS, we identified dramatic increases in endothelial cell permeability after KKS activation and liberation of BK. Furthermore, the alterations in permeability could be prevented using inhibitors that directly block BK binding, the activity of FXIIa, or the activity of KAL. Lastly, FXII binding and autoactivation is increased on the surface of hantavirus-infected EC. These data are the first to demonstrate KKS activation

  19. Non-peptide ligand binding to the formyl peptide receptor FPR2--A comparison to peptide ligand binding modes.

    Science.gov (United States)

    Stepniewski, Tomasz M; Filipek, Slawomir

    2015-07-15

    Ligands of the FPR2 receptor initiate many signaling pathways including activation of phospholipase C, protein kinase C, the mitogen-activated protein kinase, and phosphatidylinositol 3-kinase/protein kinase B pathway. The possible actions include also calcium flux, superoxide generation, as well as migration and proliferation of monocytes. FPR2 activation may induce a pro- and anti-inflammatory effect depending on the ligand type. It is also found that this receptor is involved in tumor growth. Most of currently known FPR2 ligands are agonists since they were designed based on N-formyl peptides, which are natural agonists of formyl receptors. Since the non-peptide drugs are indispensable for effective treatment strategies, we performed a docking study of such ligands employing a generated dual template homology model of the FPR2 receptor. The study revealed different binding modes of particular classes of these drugs. Based on the obtained docking poses we proposed a detailed location of three hydrophobic pockets in orthosteric binding site of FPR2. Our model emphasizes the importance of aromatic stacking, especially with regard to residues His102(3.29) and Phe257(6.51), for binding of FPR2 ligands. We also identified other residues important for non-peptide ligand binding in the binding site of FPR2. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Delayed cardioprotection is mediated via a non-peptide delta opioid agonist, SNC-121, independent of opioid receptor stimulation.

    Science.gov (United States)

    Patel, Hemal H; Hsu, Anna; Gross, Garrett J

    2004-01-01

    Acute cardioprotection is mediated primarily through delta opioid receptor stimulation independent of micro or kappa opioid receptor stimulation. Delayed cardioprotection is mediated by delta opioid receptor agonists but ambiguity remains about direct receptor involvement. Therefore, we investigated the potential of SNC-121, a non-peptide delta opioid agonist, to produce delayed cardioprotection and characterized the role of opioid receptors in this delayed response. All rats underwent 30 minutes of ischemia followed by 2 hours of reperfusion. SNC-121 induced a significant delayed cardioprotective effect. To determine the nature of this SNC-121-induced delayed cardioprotection, rats were treated with specific opioids receptor antagonists and underwent pertussis toxin (PT) treatment prior to opioid agonist stimulation. Control rats were injected with saline and allowed to recover for 24 hours. Pretreatment and early treatment with opioid receptor antagonists failed to inhibit the delayed protective effects of SNC-121, as did pretreatment with PT. Treatment with a free radical scavenger, 2-mercaptopropionyl glycine, at the time of opioid stimulation attenuated the delayed cardioprotective effects of SNC-121. These data suggest that delayed cardioprotection is stimulated via non-peptide delta opioid agonists by a mechanism unrelated to opioid receptor activation. The mechanism appears to be a non-opioid receptor mediated production of reactive oxygen species that triggers the signaling cascade leading to delayed cardioprotection.

  1. Carbohydrate-Binding Non-Peptidic Pradimicins for the Treatment of Acute Sleeping Sickness in Murine Models

    Science.gov (United States)

    Castillo-Acosta, Víctor M.; Ruiz-Pérez, Luis M.; Reichardt, Niels C.; Igarashi, Yasuhiro; Liekens, Sandra; Balzarini, Jan

    2016-01-01

    Current treatments available for African sleeping sickness or human African trypanosomiasis (HAT) are limited, with poor efficacy and unacceptable safety profiles. Here, we report a new approach to address treatment of this disease based on the use of compounds that bind to parasite surface glycans leading to rapid killing of trypanosomes. Pradimicin and its derivatives are non-peptidic carbohydrate-binding agents that adhere to the carbohydrate moiety of the parasite surface glycoproteins inducing parasite lysis in vitro. Notably, pradimicin S has good pharmaceutical properties and enables cure of an acute form of the disease in mice. By inducing resistance in vitro we have established that the composition of the sugars attached to the variant surface glycoproteins are critical to the mode of action of pradimicins and play an important role in infectivity. The compounds identified represent a novel approach to develop drugs to treat HAT. PMID:27662652

  2. Molecular modeling of interactions of the non-peptide antagonist YM087 with the human vasopressin V1a, V2 receptors and with oxytocin receptors.

    Science.gov (United States)

    Giełdoń, Artur; Kaźmierkiewicz, Rajmund; Ślusarz, Rafał; Ciarkowski, Jerzy

    2001-12-01

    The nonapeptide hormones arginine vasopressin (CYFQNCPRG-NH2, AVP) and oxytocin (CYIQNCPLG-NH2, OT), control many essential functions in mammals. Their main activities include the urine concentration (via stimulation of AVP V2 receptors, V2R, in the kidneys), blood pressure regulation (via stimulation of vascular V1a AVP receptors, V1aR), ACTH control (via stimulation of V1b receptors, V1bR, in the pituitary) and labor and lactation control (via stimulation of OT receptors, OTR, in the uterus and nipples, respectively). All four receptor subtypes belong to the GTP-binding (G) protein-coupled receptor (GPCR) family. This work consists of docking of YM087, a potent non-peptide V1aR and V2R - but not OTR - antagonist, into the receptor models based on relatively new theoretical templates of rhodopsin (RD) and opiate receptors, proposed by Mosberg et al. (Univ. of Michigan, Ann Arbor, USA). It is simultaneously demonstrated that this RD template satisfactorily compares with the first historical GPCR structure of bovine rhodopsin (Palczewski et al., 2000) and that homology-modeling of V2R, V1aR and OTR using opiate receptors as templates is rational, based on relatively high (20-60%) sequence homology among the set of 4 neurophyseal and 4 opiate receptors. YM087 was computer-docked to V1aR, V2R and OTR using the AutoDock (Olson et al., Scripps Research Institute, La Jolla, USA) and subsequently relaxed using restrained simulated annealing and molecular dynamics, as implemented in AMBER program (Kollman et al., University of California, San Francisco, USA). From about 80 diverse configurations, sampled for each of the three ligand/receptor systems, 3 best energy-relaxed complexes were selected for mutual comparisons. Similar docking modes were found for the YM087/V1aR and YM087/V2R complexes, diverse from those of the YM087/OTR complexes, in agreement with the molecular affinity data.

  3. Cell-permeable Ln(III) chelate-functionalized InP quantum dots as multimodal imaging agents.

    Science.gov (United States)

    Stasiuk, Graeme J; Tamang, Sudarsan; Imbert, Daniel; Poillot, Cathy; Giardiello, Marco; Tisseyre, Céline; Barbier, Emmanuel L; Fries, Pascal Henry; de Waard, Michel; Reiss, Peter; Mazzanti, Marinella

    2011-10-25

    Quantum dots (QDs) are ideal scaffolds for the development of multimodal imaging agents, but their application in clinical diagnostics is limited by the toxicity of classical CdSe QDs. A new bimodal MRI/optical nanosized contrast agent with high gadolinium payload has been prepared through direct covalent attachment of up to 80 Gd(III) chelates on fluorescent nontoxic InP/ZnS QDs. It shows a high relaxivity of 900 mM(-1) s(-1) (13 mM(-1 )s(-1) per Gd ion) at 35 MHz (0.81 T) and 298 K, while the bright luminescence of the QDs is preserved. Eu(III) and Tb(III) chelates were also successfully grafted to the InP/ZnS QDs. The absence of energy transfer between the QD and lanthanide emitting centers results in a multicolor system. Using this convenient direct grafting strategy additional targeting ligands can be included on the QD. Here a cell-penetrating peptide has been co-grafted in a one-pot reaction to afford a cell-permeable multimodal multimeric MRI contrast agent that reports cellular localization by fluorescence and provides high relaxivity and increased tissue retention with respect to commercial contrast agents.

  4. Cell-permeable intrinsic cellular inhibitors of apoptosis protect and rescue intestinal epithelial cells from radiation-induced cell death.

    Science.gov (United States)

    Matsuzaki-Horibuchi, Shiori; Yasuda, Takeshi; Sakaguchi, Nagako; Yamaguchi, Yoshihiro; Akashi, Makoto

    2015-01-01

    One of the important mechanisms for gastrointestinal (GI) injury following high-dose radiation exposure is apoptosis of epithelial cells. X-linked inhibitor of apoptosis (XIAP) and cellular IAP2 (cIAP2) are intrinsic cellular inhibitors of apoptosis. In order to study the effects of exogenously added IAPs on apoptosis in intestinal epithelial cells, we constructed bacterial expression plasmids containing genes of XIAP (full-length, BIR2 domain and BIR3-RING domain with and without mutations of auto-ubiquitylation sites) and cIAP2 proteins fused to a protein-transduction domain (PTD) derived from HIV-1 Tat protein (TAT) and purified these cell-permeable recombinant proteins. When the TAT-conjugated IAPs were added to rat intestinal epithelial cells IEC6, these proteins were effectively delivered into the cells and inhibited apoptosis, even when added after irradiation. Our results suggest that PTD-mediated delivery of IAPs may have clinical potential, not only for radioprotection but also for rescuing the GI system from radiation injuries.

  5. Polymer coated liposomes for use in the oral cavity - A study of the in vitro toxicity, effect on cell permeability and interaction with mucin

    DEFF Research Database (Denmark)

    Klemetsrud, Therese; Kjøniksen, Anna-Lena; Hiorth, Marianne

    2016-01-01

    (NIPAAM-co-MAA)), hydrophobically modified hydroxyethyl cellulose (HM-HEC), and hydrophobically modified ethyl hydroxyethyl cellulose (HM-EHEC). With chitosan as an exception, all the systems exhibited no significant effect on cell viability and permeability at the considered concentrations. Additionally, all the formulations...... formulations promising for oromucosal administration. Although the chitosan coated liposomes affected the cell viability, this formulation also influenced the cell permeability, which makes it an interesting candidate for systemic drug delivery from the oral cavity.......In this study we investigated the in vitro toxicity, impact on cell permeability and mucoadhesive potential of polymer coated liposomes intended for use in the oral cavity. A TR146 cell line was used as a model. The overall aim was to end up with a selection of safe polymer coated liposomes...

  6. Synthesis and Biological Evaluation of Substituted Desloratadines as Potent Arginine Vasopressin V2 Receptor Antagonists

    Directory of Open Access Journals (Sweden)

    Shuai Mu

    2014-02-01

    Full Text Available Twenty-one non-peptide substituted desloratadine class compounds were synthesized as novel arginine vasopressin receptor antagonists from desloratadine via successive acylation, reduction and acylation reactions. Their structures were characterized by 1H-NMR and HRMS, their biological activity was evaluated by in vitro and in vivo studies. The in vitro binding assay and cAMP accumulation assay indicated that these compounds are potent selective V2 receptor antagonists. Among them compounds 1n, 1t and 1v exhibited both high affinity and promising selectivity for V2 receptors. The in vivo diuretic assay demonstrated that 1t presented remarkable diuretic activity. In conclusion, 1t is a potent novel AVP V2 receptor antagonist candidate.

  7. Induction of micronuclei by a new non-peptidic mimetic farnesyltransferase inhibitor RPR-115135: role of gene mutations.

    Science.gov (United States)

    Ottoboni, C; Crippa, A; Falugi, C; Russo, P

    2001-09-01

    To investigate the relationship between oncogene activation and induction of micronuclei by a new non-peptidic mimetic farnesyltransferase inhibitor, RPR-115135, two isogenic cell lines, human colon cancer line HCT-116, which harbors a K-ras mutation, and spontaneously immortalized human breast epithelial cell line MCF-10A, were utilized. HCT-116 cells were transfected with an empty control pCMV vector (clone CMV-2) or with a dominant negative mutated p53 transgene (clone Mu-p53-2) to disrupt p53 function. In both clones RPR-115135 induced a significant increase in the frequency of micronucleation at concentrations that did not affect cell membrane integrity. RPR-115135 produced a significant increase in the ratio of CREST+ to CREST- micronuclei. MCF-10A cells were stably transfected with either c-Ha-ras or c-erbB-2 or both H-ras + c-erbB-2. No induction of micronuclei was observed. No induction of micronuclei was reported in human lymphocytes and in primary spinal cells obtained from 7-day chick embryos. In conclusion, RPR-115135 acts as an aneugenic agent in a complex manner, dependent upon the complement of mutations in cell regulatory genes in tumour cells and this activity may be independent of ras genotype.

  8. Central effects of some peptide and non-peptide opioids and naloxone on thermoregulation in the rabbit

    Science.gov (United States)

    Kandasamy, S. B.; Williams, B. A.

    1983-01-01

    The effects of several peptide and non-peptide opiods and naloxone on induced hyperthermia is studied in rabbits. The effect of tyical mu, kappa, and sigma receptor antagonists (morphine, ketocyclazcine and SKF 10,0 10, 047) and some opioid peptides (Beta-endorphin /BE/, methionine-enkaphalin /ME/, and D-Ala2-methionine-enkaphalin-amide /DAME/ are determined. The role of prostaglandins (PG), cAMP, and norepinephrine (NE) in morphine, BE, and DAME induced hyperthermia is investigated. In addition, the effect of naloxone on pyrogen, arachidonic acid, PGE2, prostacyclin, dibutyryl cAMP, and NE induced hyperthermia is determined. Among other results, it is found that the three receptor antagonists induced hyperthermia in rabbits. BE, ME, and DAME were also found to cause hyperthermia, and it is suggested that they act on the same type of receptor. It is also determined that neither NE nor cAMP is involved in the hyperthermia due to morphine, BE, and DAME. It is suggested that an action of endogenous peptides on naloxone sensitive receptors plays little role in normal thermoregulation or in hyperthermia.

  9. Discovery of substituted (4-phenyl-1H-imidazol-2-yl)methanamine as potent somatostatin receptor 3 agonists.

    Science.gov (United States)

    Lai, Zhong; He, Shuwen; Sherer, Edward C; Wu, Zhicai; Yu, Yang; Ball, Richard; Hong, Qingmei; Yang, David X; Guo, Liangqing; Li, Derun; Tuang, Quang; Chicchi, Gary G; Trusca, Dorina; Tsao, Kwei-Lan; Zhou, Yun-Ping; Howard, Andrew D; Nargund, Ravi P; Hagmann, William K

    2015-09-01

    We report SAR studies on a novel non-peptidic somatostatin receptor 3 (SSTR3) agonist lead series derived from (4-phenyl-1H-imidazol-2-yl)methanamine. This effort led to the discovery of a highly potent low molecular weight SSTR3 agonist 5c (EC50=5.2 nM, MW=359). The results from molecular overlays of 5c onto the L-129 structure indicate good alignment, and two main differences of the proposed overlays of the antagonist MK-4256 onto the conformation of 5c lead to inversion of antagonism to agonism. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. A continued saga of Boc5, the first non-peptidic glucagon-like peptide-1 receptor agonist with in vivo activities.

    Science.gov (United States)

    He, Min; Guan, Ni; Gao, Wei-wei; Liu, Qing; Wu, Xiao-yan; Ma, Da-wei; Zhong, Da-fang; Ge, Guang-bo; Li, Chuan; Chen, Xiao-yan; Yang, Ling; Liao, Jia-yu; Wang, Ming-wei

    2012-02-01

    Glucagon-like peptide-1 (GLP-1)-based therapy presents a promising option for treating type 2 diabetes. However, there are several limitations relative to the peptidic GLP-1 mimetics currently on the market or under development. This concern has led to a continued interest in the search for non-peptidic agonists for GLP-1 receptor (GLP-1R). Here, we briefly review the discovery, characterization and current status of a novel class of cyclobutane-derivative-based non-peptidic agonists for GLP-1R, including Boc5 and its newly discovered analogue WB4-24. Although the oral bioavailability of such compounds still poses great challenges, the progress made so far encourages us to identify a truly 'druggable' small molecule agonist for GLP-1R.

  11. A continued saga of Boc5, the first non-peptidic glucagon-like peptide-1 receptor agonist with in vivo activities

    Institute of Scientific and Technical Information of China (English)

    Min HE; Xiao-yan CHEN; Ling YANG; Jia-yu LIAO; Ming-wei WANG; Ni GUAN; Wei-wei GAO; Qing LIU; Xiao-yan WU; Da-wei MA; Da-fang ZHONG; Guang-bo GE; Chuan LI

    2012-01-01

    Glucagon-like peptide-1 (GLP-1)-based therapy presents a promising option for treating type 2 diabetes.However,there are several limitations relative to the peptidic GLP-1 mimetics currently on the market or under development.This concern has led to a continued interest in the search for non-peptidic agonists for GLP-1 receptor (GLP-1R).Here,we briefly review the discovery,characterization and current status of a novel class of cyclobutane-derivative-based non-peptidic agonists for GLP-1R,including Boc5 and its newly discovered analogue WB4-24.Although the oral bioavailability of such compounds still poses great challenges,the progress made so far encourages us to identify a truly 'druggable' small molecule agonist for GLP-1R.

  12. Human Lysozyme Synergistically Enhances Bactericidal Dynamics and Lowers the Resistant Mutant Prevention Concentration for Metronidazole to Helicobacter pylori by Increasing Cell Permeability

    Directory of Open Access Journals (Sweden)

    Xiaolin Zhang

    2016-10-01

    Full Text Available Metronidazole (MNZ is an effective agent that has been employed to eradicate Helicobacter pylori (H. pylori. The emergence of broad MNZ resistance in H. pylori has affected the efficacy of this therapeutic agent. The concentration of MNZ, especially the mutant prevention concentration (MPC, plays an important role in selecting or enriching resistant mutants and regulating therapeutic effects. A strategy to reduce the MPC that can not only effectively treat H. pylori but also prevent resistance mutations is needed. H. pylori is highly resistant to lysozyme. Lysozyme possesses a hydrolytic bacterial cell wall peptidoglycan and a cationic dependent mode. These effects can increase the permeability of bacterial cells and promote antibiotic absorption into bacterial cells. In this study, human lysozyme (hLYS was used to probe its effects on the integrity of the H. pylori outer and inner membranes using as fluorescent probe hydrophobic 1-N-phenyl-naphthylamine (NPN and the release of aspartate aminotransferase. Further studies using a propidium iodide staining method assessed whether hLYS could increase cell permeability and promote cell absorption. Finally, we determined the effects of hLYS on the bactericidal dynamics and MPC of MNZ in H. pylori. Our findings indicate that hLYS could dramatically increase cell permeability, reduce the MPC of MNZ for H. pylori, and enhance its bactericidal dynamic activity, demonstrating that hLYS could reduce the probability of MNZ inducing resistance mutations.

  13. ADME Properties Evaluation in Drug Discovery: Prediction of Caco-2 Cell Permeability Using a Combination of NSGA-II and Boosting.

    Science.gov (United States)

    Wang, Ning-Ning; Dong, Jie; Deng, Yin-Hua; Zhu, Min-Feng; Wen, Ming; Yao, Zhi-Jiang; Lu, Ai-Ping; Wang, Jian-Bing; Cao, Dong-Sheng

    2016-04-25

    The Caco-2 cell monolayer model is a popular surrogate in predicting the in vitro human intestinal permeability of a drug due to its morphological and functional similarity with human enterocytes. A quantitative structure-property relationship (QSPR) study was carried out to predict Caco-2 cell permeability of a large data set consisting of 1272 compounds. Four different methods including multivariate linear regression (MLR), partial least-squares (PLS), support vector machine (SVM) regression and Boosting were employed to build prediction models with 30 molecular descriptors selected by nondominated sorting genetic algorithm-II (NSGA-II). The best Boosting model was obtained finally with R(2) = 0.97, RMSEF = 0.12, Q(2) = 0.83, RMSECV = 0.31 for the training set and RT(2) = 0.81, RMSET = 0.31 for the test set. A series of validation methods were used to assess the robustness and predictive ability of our model according to the OECD principles and then define its applicability domain. Compared with the reported QSAR/QSPR models about Caco-2 cell permeability, our model exhibits certain advantage in database size and prediction accuracy to some extent. Finally, we found that the polar volume, the hydrogen bond donor, the surface area and some other descriptors can influence the Caco-2 permeability to some extent. These results suggest that the proposed model is a good tool for predicting the permeability of drug candidates and to perform virtual screening in the early stage of drug development.

  14. Design and synthesis of a cell-permeable, drug-like small molecule inhibitor targeting the polo-box domain of polo-like kinase 1.

    Directory of Open Access Journals (Sweden)

    Ganipisetti Srinivasrao

    Full Text Available Polo-like kinase-1 (Plk1 plays a crucial role in cell proliferation and the inhibition of Plk1 has been considered as a potential target for specific inhibitory drugs in anti-cancer therapy. Several research groups have identified peptide-based inhibitors that target the polo-box domain (PBD of Plk1 and bind to the protein with high affinity in in vitro assays. However, inadequate proteolytic resistance and cell permeability of the peptides hinder the development of these peptide-based inhibitors into novel therapeutic compounds.In order to overcome the shortcomings of peptide-based inhibitors, we designed and synthesized small molecule inhibitors. Among these molecules, bg-34 exhibited a high binding affinity for Plk1-PBD and it could cross the cell membrane in its unmodified form. Furthermore, bg-34-dependent inhibition of Plk1-PBD was sufficient for inducing apoptosis in HeLa cells. Moreover, modeling studies performed on Plk1-PBD in complex with bg-34 revealed that bg-34 can interact effectively with Plk1-PBD.We demonstrated that the molecule bg-34 is a potential drug candidate that exhibits anti-Plk1-PBD activity and possesses the favorable characteristics of high cell permeability and stability. We also determined that bg-34 induced apoptotic cell death by inhibiting Plk1-PBD in HeLa cells at the same concentration as PEGylated 4j peptide, which can inhibit Plk1-PBD activity 1000 times more effectively than bg-34 can in in vitro assays. This study may help to design and develop drug-like small molecule as Plk1-PBD inhibitor for better therapeutic activity.

  15. Discovery of Sanggenon G as a natural cell-permeable small-molecular weight inhibitor of X-linked inhibitor of apoptosis protein (XIAP).

    Science.gov (United States)

    Seiter, Maximilian A; Salcher, Stefan; Rupp, Martina; Hagenbuchner, Judith; Kiechl-Kohlendorfer, Ursula; Mortier, Jérémie; Wolber, Gerhard; Rollinger, Judith M; Obexer, Petra; Ausserlechner, Michael J

    2014-01-01

    Defects in the regulation of apoptosis are one main cause of cancer development and may result from overexpression of anti-apoptotic proteins such as the X-linked inhibitor of apoptosis protein (XIAP). XIAP is frequently overexpressed in human leukemia and prostate and breast tumors. Inhibition of apoptosis by XIAP is mainly coordinated through direct binding to the initiator caspase-9 via its baculovirus-IAP-repeat-3 (BIR3) domain. XIAP inhibits caspases directly making it to an attractive target for anti-cancer therapy. In the search for novel, non-peptidic XIAP inhibitors in this study we focused on the chemical constituents of sāng bái pí (mulberry root bark). Most promising candidates of this plant were tested biochemically in vitro by a fluorescence polarization (FP) assay and in vivo via protein fragment complementation analysis (PCA). We identified the Diels Alder adduct Sanggenon G (SG1) as a novel, small-molecular weight inhibitor of XIAP. As shown by FP and PCA analyses, SG1 binds specifically to the BIR3 domain of XIAP with a binding affinity of 34.26 μM. Treatment of the transgenic leukemia cell line Molt3/XIAP with SG1 enhances caspase-8, -3 and -9 cleavage, displaces caspase-9 from XIAP as determined by immunoprecipitation experiments and sensitizes these cells to etoposide-induced apoptosis. SG1 not only sensitizes the XIAP-overexpressing leukemia cell line Molt3/XIAP to etoposide treatment but also different neuroblastoma cell lines endogenously expressing high XIAP levels. Taken together, Sanggenon G (SG1) is a novel, natural, non-peptidic, small-molecular inhibitor of XIAP that can serve as a starting point to develop a new class of improved XIAP inhibitors.

  16. New pyrazolopyrimidine inhibitors of protein kinase d as potent anticancer agents for prostate cancer cells.

    Directory of Open Access Journals (Sweden)

    Manuj Tandon

    Full Text Available The emergence of protein kinase D (PKD as a potential therapeutic target for several diseases including cancer has triggered the search for potent, selective, and cell-permeable small molecule inhibitors. In this study, we describe the identification, in vitro characterization, structure-activity analysis, and biological evaluation of a novel PKD inhibitory scaffold exemplified by 1-naphthyl PP1 (1-NA-PP1. 1-NA-PP1 and IKK-16 were identified as pan-PKD inhibitors in a small-scale targeted kinase inhibitor library assay. Both screening hits inhibited PKD isoforms at about 100 nM and were ATP-competitive inhibitors. Analysis of several related kinases indicated that 1-NA-PP1 was highly selective for PKD as compared to IKK-16. SAR analysis showed that 1-NA-PP1 was considerably more potent and showed distinct substituent effects at the pyrazolopyrimidine core. 1-NA-PP1 was cell-active, and potently blocked prostate cancer cell proliferation by inducing G2/M arrest. It also potently blocked the migration and invasion of prostate cancer cells, demonstrating promising anticancer activities on multiple fronts. Overexpression of PKD1 or PKD3 almost completely reversed the growth arrest and the inhibition of tumor cell invasion caused by 1-NA-PP1, indicating that its anti-proliferative and anti-invasive activities were mediated through the inhibition of PKD. Interestingly, a 12-fold increase in sensitivity to 1-NA-PP1 could be achieved by engineering a gatekeeper mutation in the active site of PKD1, suggesting that 1-NA-PP1 could be paired with the analog-sensitive PKD1(M659G for dissecting PKD-specific functions and signaling pathways in various biological systems.

  17. Topical non-peptide antagonists of sensory neurotransmitters substance P and CGRP do not modify patch test and prick test reactions

    DEFF Research Database (Denmark)

    Wallengren, Joanna; Edvinsson, Lars

    2014-01-01

    developed. Their effect on the skin barrier was measured in terms of transepidermal water loss (TEWL) while permeation was calculated using permeation coefficients. Patch tests in patients allergic to nickel and prick test reactions to histamine were used as models. None of the treatments increased TEWL...... vasoconstriction in the skin but did not change the infiltration of nickel reactions. None of the treatments influenced the nickel patch test induced pruritus. The data suggest that the topical application of non-peptide antagonists penetrates the skin but does not inhibit contact dermatitis or pruritus.......Immunologic responses in the skin can be modulated by such neurotransmitters of sensory nerve fibers as substance P (SP) and calcitonin gene-related peptide (CGRP). The first-generation receptor antagonists were peptides with large molecules and had to be injected intracutaneously. The aim...

  18. Site-directed mutagenesis at the human B2 receptor and molecular modelling to define the pharmacophore of non-peptide bradykinin receptor antagonists.

    Science.gov (United States)

    Meini, Stefania; Cucchi, Paola; Bellucci, Francesca; Catalani, Claudio; Faiella, Angela; Rotondaro, Luigi; Quartara, Laura; Giolitti, Alessandro; Maggi, Carlo Alberto

    2004-02-15

    Combining site-directed mutagenesis with information obtained from molecular modelling of the bradykinin (BK) human B2 receptor (hB2R) as derived from the bovine rhodopsin crystal structure [Science 289 (2000) 739], we previously defined a putative binding mode for the non-peptide B2 receptor antagonists, FR173657 and LF16-0687 [Can J Physiol Pharmacol 80 (2002) 303]. The present work is aimed to define the specific role of the quinoline moiety in the pharmacophore of these non-peptide antagonists. The effect of the mutations I110A, L114A (TM, transmembrane 3), W256A (TM6), F292A, Y295A and Y295F (TM7) was evaluated. None of the mutations affected the binding interaction of peptide ligands: the agonist BK and the peptide antagonist MEN 11270. The affinities in competing for [3H]-BK binding and in blocking the BK-induced IP production by the non-peptide antagonists LF16-0687 and FR173657 at the wild type and mutant receptors were analysed. While the affinities of LF16-0687 and FR173657 were crucially decreased at the I110A, Y295A, and Y295F mutants, the W256A mutation affected the affinity of the LF16-0687 only. The important contribution of the quinoline moiety was shown by the inability of an analogue of LF16-0687, lacking this moiety, to affect BK binding at the wild type receptor. On the other hand, the benzamidine group did not interact with mutated residues, since LF16-0687 analogues without this group or with an oxidated benzamidine displayed pairwise loss of affinity on wild type and mutated receptors. Further differences between FR173657 and LF16-0687 were highlighted at the I110 and Y295 mutants when comparing binding (pK(i)) and functional antagonist (pKB) affinity. First, the I110A mutation similarly impaired their binding affinity (250-fold), but at a less extent the antagonist potency of FR173657 only. Second, both the hydroxyl and the phenyl moieties of the Y295 residue had a specific role in the LF16-0687 interaction with the receptor, as

  19. CGRP receptors mediating CGRP-, adrenomedullin- and amylin-induced relaxation in porcine coronary arteries. Characterization with 'Compound 1' (WO98/11128), a non-peptide antagonist

    DEFF Research Database (Denmark)

    Hasbak, P; Sams, A; Schifter, S

    2001-01-01

    1. Calcitonin gene-related peptide (CGRP), amylin and adrenomedullin (AM) belong to the same family of peptides. Accumulating evidence indicate that the calcitonin (CT) receptor, the CT receptor-like receptor (CRLR) and receptor-activity-modifying proteins (RAMPs) form the basis of all the recept......1. Calcitonin gene-related peptide (CGRP), amylin and adrenomedullin (AM) belong to the same family of peptides. Accumulating evidence indicate that the calcitonin (CT) receptor, the CT receptor-like receptor (CRLR) and receptor-activity-modifying proteins (RAMPs) form the basis of all....... The partial porcine mRNA sequences shared 82 - 92% nucleotide identity with human sequences. 3. The human peptides alphaCGRP, betaCGRP, AM and amylin induced relaxation with pEC(50) values of 8.1, 8.1, 6.7 and 6.1 M respectively. 4. The antagonistic properties of a novel non-peptide CGRP antagonist 'Compound...

  20. Novel Non-Peptide Inhibitors against SmCL1 of Schistosoma mansoni: In Silico Elucidation, Implications and Evaluation via Knowledge Based Drug Discovery.

    Science.gov (United States)

    Zafar, Atif; Ahmad, Sabahuddin; Rizvi, Asim; Ahmad, Masood

    2015-01-01

    Schistosomiasis is a major endemic disease known for excessive mortality and morbidity in developing countries. Because praziquantel is the only drug available for its treatment, the risk of drug resistance emphasizes the need to discover new drugs for this disease. Cathepsin SmCL1 is the critical target for drug design due to its essential role in the digestion of host proteins for growth and development of Schistosoma mansoni. Inhibiting the function of SmCL1 could control the wide spread of infections caused by S. mansoni in humans. With this objective, a homology modeling approach was used to obtain theoretical three-dimensional (3D) structure of SmCL1. In order to find the potential inhibitors of SmCL1, a plethora of in silico techniques were employed to screen non-peptide inhibitors against SmCL1 via structure-based drug discovery protocol. Receiver operating characteristic (ROC) curve analysis and molecular dynamics (MD) simulation were performed on the results of docked protein-ligand complexes to identify top ranking molecules against the modelled 3D structure of SmCL1. MD simulation results suggest the phytochemical Simalikalactone-D as a potential lead against SmCL1, whose pharmacophore model may be useful for future screening of potential drug molecules. To conclude, this is the first report to discuss the virtual screening of non-peptide inhibitors against SmCL1 of S. mansoni, with significant therapeutic potential. Results presented herein provide a valuable contribution to identify the significant leads and further derivatize them to suitable drug candidates for antischistosomal therapy.

  1. 1,2,3-Triazolyl ester of Ketorolac: A "Click Chemistry"-based highly potent PAK1-blocking cancer-killer.

    Science.gov (United States)

    Nguyen, Binh Cao Quan; Takahashi, Hideaki; Uto, Yoshihiro; Shahinozzaman, M D; Tawata, Shinkichi; Maruta, Hiroshi

    2017-01-27

    An old anti-inflammatory/analgesic drug called Toradol is a racemic form of Ketorolac (50% R-form and 50% S-form) that blocks the oncogenic RAC-PAK1-COX-2 (cyclooxygenase-2) signaling, through the direct inhibition of RAC by the R-form and of COX-2 by the S-form, eventually down-regulating the production of prostaglandins. However, due to its COOH moiety which is clearly repulsive to negatively-charged phospholipid-based plasma membrane, its cell-permeability is rather poor (the IC50 against the growth of human cancer cells such as A549 is around 13 μM). In an attempt to boost its anti-cancer activity, hopefully by increasing its cell-permeability through abolishing the negative charge, yet keeping its water-solubility, here we synthesized a 1,2,3-triazolyl ester of Toradol through "Click Chemistry". The resultant water-soluble "azo" derivative called "15K" was found to be over 500 times more potent than Toradol with the IC50 around 24 nM against the PAK1-dependent growth of A549 cancer cells, inactivating PAK1 in cell culture with the apparent IC50 around 65 nM, and inhibiting COX-2 in vitro with the IC50 around 6 nM. Furthermore, the Click Chemistry boosts the anti-cancer activity of Ketorolac by 5000 times against the PAK1-independent growth of B16F10 melanoma cells. Using a multi-drug-resistant (MDR) cancer cell line (EMT6), we found that the esterization of Ketorolac boosts its cell-permeability by at least 10 folds. Thus, the Click Chemistry dramatically boosts the anti-cancer activity of Ketorolac, at least in three ways: increasing its cell-permeability, the anti-PAK1 activity of R-form and anti-COX-2 activity of S-form. The resultant "15K" is so far among the most potent PAK1-blockers, and therefore would be potentially useful for the therapy of many different PAK1-dependent diseases/disorders such as cancers.

  2. Neuropeptides and neuropeptide receptors: drug targets, and peptide and non-peptide ligands: a tribute to Prof. Dieter Seebach.

    Science.gov (United States)

    Hoyer, Daniel; Bartfai, Tamas

    2012-11-01

    both central and peripheral nervous system disorders. Both, receptor subtype-selective antagonists and agonists are being developed, as illustrated by the success of somatostatin agonists, angiotensin, and endothelin antagonists, and the expected clinical applications of NK-1/2/3 (substance P) receptor antagonists, CRF, vasopressin, NPY, neurotensin, orexin antagonists, or neuropeptide receptor modulators; such ligands have efficacy in preclinical or clinical models of pain and neuropsychiatric diseases, such as migraine, chronic/neuropathic pain, anxiety, sleep disorders, depression, and schizophrenia. In addition, both positive and negative allosteric modulators have been described with interesting in vivo activities (e.g., at galanin receptors). The field has become more complex now that an increasing number of heteromeric neuropeptide receptors are described, e.g., ghrelin receptors with 5-HT(2C) or dopamine D(1), D(2) receptors. At long last, structure-based drug discovery can now be envisaged with confidence, since crystal or solution structure of GPCRs and GPCR-ligand complexes, including peptide receptors, are published almost on a monthly basis. Finally, although most compounds acting at peptide receptors are still peptidomimetics, the last decade has seen the emergence of low-molecular-weight nonpeptide ligands (e.g., for orexin, ghrelin, or neurokinin receptors), and surprising progress has been made with β- and γ-peptides as very stable and potent mimetics of, e.g., somatostatin (SRIF), where the native SRIF has a half-life limited to 2-3 min. This last point will be illustrated more specifically, as we have had a long-standing collaboration with Prof. D. Seebach to whom this review is dedicated at the occasion of his 75th birthday.

  3. A cell-permeable dominant-negative survivin protein induces apoptosis and sensitizes prostate cancer cells to TNF-α therapy

    Directory of Open Access Journals (Sweden)

    Kanwar Jagat R

    2010-10-01

    Full Text Available Abstract Background Survivin is a member of the inhibitor-of-apoptosis (IAP family which is widely expressed by many different cancers. Overexpression of survivin is associated with drug resistance in cancer cells, and reduced patient survival after chemotherapy and radiotherapy. Agents that antagonize the function of survivin hold promise for treating many forms of cancer. The purpose of this study was to investigate whether a cell-permeable dominant-negative survivin protein would demonstrate bioactivity against prostate and cervical cancer cells grown in three dimensional culture. Results A dominant-negative survivin (C84A protein fused to the cell penetrating peptide poly-arginine (R9 was expressed in E. coli and purified by affinity chromatography. Western blot analysis revealed that dNSurR9-C84A penetrated into 3D-cultured HeLa and DU145 cancer cells, and a cell viability assay revealed it induced cancer cell death. It increased the activities of caspase-9 and caspase-3, and rendered DU145 cells sensitive to TNF-α via by a mechanism involving activation of caspase-8. Conclusions The results demonstrate that antagonism of survivin function triggers the apoptosis of prostate and cervical cancer cells grown in 3D culture. It renders cancer cells sensitive to the proapoptotic affects of TNF-α, suggesting that survivin blocks the extrinsic pathway of apoptosis. Combination of the biologically active dNSurR9-C84A protein or other survivin antagonists with TNF-α therapy warrants consideration as an approach to cancer therapy.

  4. Reversal of obesity and insulin resistance by a non-peptidic glucagon-like peptide-1 receptor agonist in diet-induced obese mice.

    Directory of Open Access Journals (Sweden)

    Min He

    Full Text Available BACKGROUND: Glucagon-like peptide-1 (GLP-1 is recognized as an important regulator of glucose homeostasis. Efforts to utilize GLP-1 mimetics in the treatment of diabetes have yielded clinical benefits. A major hurdle for an effective oral therapy has been the difficulty of finding a non-peptidic GLP-1 receptor (GLP-1R agonist. While its oral bioavailability still poses significant challenges, Boc5, one of the first such compounds, has demonstrated the attainment of GLP-1R agonism in diabetic mice. The present work was to investigate whether subchronic Boc5 treatment can restore glycemic control and induce sustainable weight loss in diet-induced obese (DIO mice, an animal model of human obesity and insulin resistance. METHODOLOGY/PRINCIPAL FINDINGS: DIO mice were treated three times a week with Boc5 (0.3, 1 and 3 mg for 12 weeks. Body weight, body mass index (BMI, food intake, fasting glucose, intraperitoneal glucose tolerance and insulin induced glucose clearance were monitored regularly throughout the treatment. Glucose-stimulated insulin secretion, β-cell mass, islet size, body composition, serum metabolic profiles, lipogenesis, lipolysis, adipose hypertrophy and lipid deposition in the liver and muscle were also measured after 12 weeks of dosing. Boc5 dose-dependently reduced body weight, BMI and food intake in DIO mice. These changes were associated with significant decreases in fat mass, adipocyte hypertrophy and peripheral tissue lipid accumulation. Boc5 treatment also restored glycemic control through marked improvement of insulin sensitivity and normalization of β-cell mass. Administration of Boc5 (3 mg reduced basal but enhanced insulin-mediated glucose incorporation and noradrenaline-stimulated lipolysis in isolated adipocytes from obese mice. Furthermore, circulating leptin, adiponectin, triglyceride, total cholesterol, nonesterified fatty acid and high-density lipoprotein/low-density lipoprotein ratio were normalized to various

  5. The effect of peptidic and non-peptidic proteasome inhibitors on the biological properties of Acanthamoeba castellanii belonging to the T4 genotype.

    Science.gov (United States)

    Siddiqui, Ruqaiyyah; Saleem, Sahreena; Khan, Naveed Ahmed

    2016-09-01

    The treatment of Acanthamoeba infections remains problematic, suggesting that new targets and/or chemotherapeutic agents are needed. Bioassay-guided screening of drugs that are clinically-approved for non-communicable diseases against opportunistic eukaryotic pathogens is a viable strategy. With known targets and mode of action, such drugs can advance to clinical trials at a faster pace. Recently Bortezomib (proteasome inhibitor) has been approved by FDA in the treatment of multiple myeloma. As proteasomal pathways are well known regulators of a variety of eukaryotic cellular functions, the overall aim of the present study was to study the effects of peptidic and non-peptidic proteasome inhibitors on the biology and pathogenesis of Acanthamoeba castellanii of the T4 genotype, in vitro. Zymographic assays revealed that inhibition of proteasome had detrimental effects on the extracellular proteolytic activities of A. castellanii. Proteasome inhibition affected A. castellanii growth (using amoebistatic assays), but not viability of A. castellanii. Importantly, proteasome inhibitors affected encystation as determined by trophozoite transformation into the cyst form, as well as excystation, as determined by cyst transformation into the trophozoite form. The ability of proteasome inhibitor to block Acanthamoeba differentiation is significant, as it presents a major challenge in the successful treatment of Acanthamoeba infection. As these drugs are used clinically against non-communicable diseases, the findings reported here have the potential to be tested in a clinical setting against amoebic infections.

  6. Dopamine-dependent behavioural stimulation by non-peptide delta opioids BW373U86 and SNC 80: 1. Locomotion, rearing and stereotypies in intact rats.

    Science.gov (United States)

    Spina, L; Longoni, R; Mulas, A; Chang, K J; Di Chiara, G

    1998-02-01

    The unconditioned behavioural effects of two non-peptide delta-opioid receptor agonists, BW 373U86 and SNC 80, were studied in the intact rat. BW 373U86 (0.1-2.5 mg/kg s.c.) and SNC 80 (2.5-10 mg/kg s.c.) dose-dependently elicited locomotion, rearing, stereotyped sniffing, licking and gnawing. These effects were abolished by pretreatment with the delta-opioid receptor antagonist naltrindole (5.0 mg/kg s.c.). In view of the phenomenological similarities between this syndrome and that elicited by dopamine-receptor agonists, the role played by dopamine receptors was investigated. The specific dopamine D1 receptor antagonist SCH 23390 and the specific dopamine D2/D3 receptor antagonist raclopride reduced or even abolished the behavioural stimulation induced by lower doses of BW 373U86 and SNC 80. When higher doses of BW 373U86 were used (2.5 mg/kg), however, raclopride, even at high cataleptic doses (6.0 mg/kg), only partly prevented the behavioural stimulation induced by the delta-opioid receptor agonist. The behavioural stimulation remaining after high doses of raclopride was abolished by the administration of SCH 23390. These results show that delta-opioid receptor stimulation elicits dopamine-dependent behavioural activation in the rat that depends on dopamine receptors, particularly of the D1 subtype.

  7. Potent new greenhouse gas discovered

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2001-02-01

    Discovery of a new greenhouse gas by scientists of the Max Planck Institute for Chemistry in Mainz, Germany, is reported. The newly detected compound --trifluoromethyl sulfur pentafluoride -- is of industrial origin and is considered to be the most potent greenhouse gas identified to date. Its source remains a mystery, but is believed to be related to SF{sub 6}, a compound used in in high voltage electrical equipment to suppress sparks, in protecting metals during a melting process, in tennis balls, car tires and running shoes. In the past it has also been used as a noise barrier in double glazed window panes. The molecule is extremely resistant to the natural self-cleaning property of the atmosphere, has a long lifetime -- somewhere between several hundred and several thousand years. The gas was discovered during expeditions to Antarctica while extracting air samples from a thick firm layer of snow.

  8. The cell-permeable Aβ1-6A2VTAT(D) peptide reverts synaptopathy induced by Aβ1-42wt.

    Science.gov (United States)

    Cimini, Sara; Sclip, Alessandra; Mancini, Simona; Colombo, Laura; Messa, Massimo; Cagnotto, Alfredo; Di Fede, Giuseppe; Tagliavini, Fabrizio; Salmona, Mario; Borsello, Tiziana

    2016-05-01

    Alzheimer disease (AD) is the most prevalent form of dementia. Loss of hippocampal synapses is the first neurodegenerative event in AD. Synaptic loss has been associated with the accumulation in the brain parenchyma of soluble oligomeric forms of amyloid β peptide (Aβ1-42wt). Clinical observations have shown that a mutation in the APP protein (A673V) causes an early onset AD-type dementia in homozygous carriers while heterozygous carriers are unaffected. This mutation leads to the formation of mutated Aβ peptides (Aβ1-42A2V) in homozygous patients, while in heterozygous subjects both Aβ1-42wt and Aβ1-42A2V are present. To better understand the impact of the A673V mutation in AD, we analyzed the synaptotoxic effect of oligomers formed by aggregation of different Aβ peptides (Aβ1-42wt or Aβ1-42A2V) and the combination of the two Aβ1-42MIX (Aβ1-42wt and Aβ1-42A2V) in an in vitro model of synaptic injury. We showed that Aβ1-42A2V oligomers are more toxic than Aβ1-42wt oligomers in hippocampal neurons, confirming the results previously obtained in cell lines. Furthermore, we reported that oligomers obtained by the combination of both wild type and mutated peptides (Aβ1-42MIX) did not exert synaptic toxicity. We concluded that the combination of Aβ1-42wt and Aβ1-42A2V peptides hinders the toxicity of Aβ1-42A2V and counteracts the manifestation of synaptopathy in vitro. Finally we took advantage of this finding to generate a cell-permeable peptide for clinical application, by fusing the first six residues of the Aβ1-42A2V to the TAT cargo sequence (Aβ1-6A2VTAT(D)). Noteworthy, the treatment with Aβ1-6A2VTAT(D) confers neuroprotection against both in vitro and in vivo synaptopathy models. Therefore Aβ1-6A2VTAT(D) may represent an innovative therapeutic tool to prevent synaptic degeneration in AD.

  9. Competitive inhibition of survivin using a cell-permeable recombinant protein induces cancer-specific apoptosis in colon cancer model

    Directory of Open Access Journals (Sweden)

    Roy K

    2015-02-01

    Full Text Available Kislay Roy,1 Rupinder K Kanwar,1 Subramanian Krishnakumar,2,3 Chun Hei Antonio Cheung,4 Jagat R Kanwar1 1Nanomedicine-Laboratory of Immunology and Molecular Biomedical Research (NLIMBR, Molecular and Medical Research (MMR Strategic Research Centre, School of Medicine (SoM, Faculty of Health, Deakin University, Waurn Ponds, VIC, Australia; 2Department of Nanobiotechnology, 3Larsen & Toubro (L&T Ocular Pathology Department, Vision Research Foundation, Kamalnayan Bajaj Institute for Research in Vision and Ophthalmology, Chennai, India; 4Department of Pharmacology, College of Medicine, National Cheng Kung University, Tainan, Taiwan, Republic of China Abstract: Endogenous survivin expression has been related with cancer survival, drug resistance, and metastasis. Therapies targeting survivin have been shown to significantly inhibit tumor growth and recurrence. We found out that a cell-permeable dominant negative survivin (SurR9-C84A, referred to as SR9 competitively inhibited endogenous survivin and blocked the cell cycle at the G1/S phase. Nanoencapsulation in mucoadhesive chitosan nanoparticles (CHNP substantially increased the bioavailability and serum stability of SR9. The mechanism of nanoparticle uptake was studied extensively in vitro and in ex vivo models. Our results confirmed that CHNP–SR9 protected primary cells from autophagy and successfully induced tumor-specific apoptosis via both extrinsic and intrinsic apoptotic pathways. CHNP–SR9 significantly reduced the tumor spheroid size (three-dimensional model by nearly 7-fold. Effects of SR9 and CHNP–SR9 were studied on 35 key molecules involved in the apoptotic pathway. Highly significant (4.26-fold, P≤0.005 reduction in tumor volume was observed using an in vivo mouse xenograft colon cancer model. It was also observed that net apoptotic (6.25-fold, P≤0.005 and necrotic indexes (3.5-fold, P≤0.05 were comparatively higher in CHNP–SR9 when compared to void CHNP and CHNP–SR9

  10. Limitations in the Use of Fluorescein Diacetate/Propidium Iodide (FDA/PI) and Cell Permeable Nucleic Acid Stains for Viability Measurements of Isolated Islets of Langerhans.

    Science.gov (United States)

    Boyd, Vinc; Cholewa, Olivia Maria; Papas, Klearchos K

    2008-03-01

    BACKGROUND: A review of current literature shows that the combined use of the cell permeable esterase-substrate fluorescein diacetate (FDA) and the cell impermeant nucleic acid stain propidium iodide (PI) to be one of the most common fluorescence-based methods to assess the viability of isolated islets of Langerhans, and it is currently used for islet product release prior to transplantation in humans. However, results from this assay do not correlate with islet viability and function or islet transplantation success in animals or humans (Eckhard et al. 2004; Ricordi et al. 2001). This may be in part attributed to considerable differences as well as discrepancies in the use of these reagents on islets. We critically surveyed the literature and evaluated the impact of a number of variables associated with the use of FDA/PI to determine their reliability in assessing islet cell viability. In addition, we evaluated other fluorescent stains, such as SYTO(R)13, SYTO(R)24 and SYBR(R)14 as possible alternatives to FDA. RESULTS: We found that the stability of stains in storage and stock solutions, the number of islets stained, concentration of stains, staining incubation time, the buffer/media used, and the method of examining islets were significant in the final scoring of viability. For archival file photos, the exposure time and camera/software settings can also impact interpretation of viability. Although our results show that FDA does detect intracellular esterase activity and staining with PI does assess cell membrane integrity, the results obtained from using these stains did not correlate directly with expected islet function and viability per transplantation into diabetic athymic nude mice (Papas et al. 2007). In addition, the use of two nucleic acid stains, such as SYTO(R)13 and PI, for live/dead scoring exhibited staining anomalies which limit their accuracy in assessing islet viability. CONCLUSIONS: From a review of the literature and from our observations on

  11. Dopamine-dependent behavioural stimulation by non-peptide delta opioids BW373U86 and SNC 80: 2. Place-preference and brain microdialysis studies in rats.

    Science.gov (United States)

    Longoni, R; Cadoni, C; Mulas, A; Di Chiara, G; Spina, L

    1998-02-01

    The motivational properties of the non-peptide delta-opioid receptor agonists BW373U86 and SNC 80 were investigated using the place-conditioning paradigm. BW373U86 (0.5-1.0 mg/kg s.c.) and SNC 80 (1.25-5.0 mg/kg s.c.) elicited significant preference for the drug-paired compartment, in a dose-related fashion. Naltrindole (5.0 mg/kg s.c.) pretreatment, while failing to modify preference when given alone, completely prevented place-preference induced by BW373U86 (1.0 mg/kg s.c.) and SNC 80 (1.25 mg/kg s.c.). The dopamine D1 receptor antagonist SCH23390, given at doses that do not affect place-preference (0.012 mg/kg s.c.), completely prevented the place-preference induced by BW373U86 and SNC 80. At the doses effective in eliciting place-preference, BW373U86 and SNC 80 failed to modify extracellular dopamine in the medial nucleus accumbens, while in the dorso-lateral caudate-putamen BW373U86 (1.0 and 2.5 mg/kg s.c.) reduced extracellular dopamine, and this effect was prevented by naltrindole (5.0 mg/kg s.c.). SNC 80, only at the dose of 5 mg/kg s.c., significantly reduced extracellular DA in the dorso-lateral caudate-putamen. The results indicate that stimulation of delta-opioid receptors has incentive properties that might be related to an indirect amplification of post-synaptic dopamine transmission.

  12. House dust extracts contain potent immunological adjuvants

    NARCIS (Netherlands)

    Beukelman, C.J.; Dijk, H. van; Aerts, P.C.; Rademaker, P.M.; Berrens, L.; Willers, J.M.N.

    1987-01-01

    A crude aqueous extract of house dust and two house dust subfractions were tested for adjuvant activity in a sensitivity assay performed in mice. Evidence is presented that house dust contains at least two potent immunological adjuvants. One of these, present in both subfractions, was probably endot

  13. Phenyltriazolinones as potent factor Xa inhibitors.

    Science.gov (United States)

    Quan, Mimi L; Pinto, Donald J P; Rossi, Karen A; Sheriff, Steven; Alexander, Richard S; Amparo, Eugene; Kish, Kevin; Knabb, Robert M; Luettgen, Joseph M; Morin, Paul; Smallwood, Angela; Woerner, Francis J; Wexler, Ruth R

    2010-02-15

    We have discovered that phenyltriazolinone is a novel and potent P1 moiety for coagulation factor Xa. X-ray structures of the inhibitors with a phenyltriazolinone in the P1 position revealed that the side chain of Asp189 has reoriented resulting in a novel S1 binding pocket which is larger in size to accommodate the phenyltriazolinone P1 substrate.

  14. Peripherally Administered Non-peptide Oxytocin Antagonist, L368,899®, Accumulates in Limbic Brain Areas: A New Pharmacological Tool for the Study of Social Motivation in Non-Human Primates

    Science.gov (United States)

    Boccia, Maria L.; Goursaud, Anne-Pierre S.; Bachevalier, Jocelyne; Anderson, Kenneth D.; Pedersen, Cort A.

    2009-01-01

    Central administration of oxytocin (OT) antagonists inhibits maternal and sexual behavior in non-primates, providing the strongest experimental evidence that endogenous OT facilitates these behaviors. While there have been a few reports that ICV administration of OT increases social behaviors in monkeys, no studies to date have assessed the effects of OT antagonists. Therefore, we studied in rhesus monkeys whether L368,899®, a non-peptide antagonist produced by Merck that selectively blocks the human uterine OT receptor, penetrates the CNS after peripheral administration and alters female maternal and sexual behavior. In two studies in four male monkeys, L368,899 was injected iv (1 mg/kg) after which (1) CSF samples were collected at intervals over 4 h and (2) brains were collected at 60 min. Assay of samples confirmed that iv-administered L368,899 entered CSF and accumulated in the hypothalamus, septum, orbitofrontal cortex, amygdala and hippocampus, but not other areas. An adult female monkey was tested for interest in either an infant or sexual behavior, receiving a different iv treatment prior to each test (1 or 3 mg/kg of L368,899 or saline) OT antagonist treatment reduced or eliminated interest in the infant and sexual behavior. These results, although preliminary, are the first to directly implicate endogenous OT in activation of primate maternal interest and sexual behavior. While it remains to be empirically demonstrated that peripherally administered L368,899 blocks central OT receptors, our behavioral findings suggest that this non-peptide antagonist may facilitate testing OT involvement in a variety of social and other behaviors in primates. PMID:17583705

  15. K-POTENT PRESERVING LINEAR MAPS

    Institute of Scientific and Technical Information of China (English)

    侯绳照; 侯晋川

    2002-01-01

    Let B(X) be the Banach algebra of all bounded linear operators on a complcx Banach space X. Let k ≥ 2 be an integer and φ a weakly continuous linear surjective map from B(X) into itself. It is shown that φ is k-potent preserving if and only if it is k-th-power preserving, and in turn, if and only if it is either an automorphism or an antiautomorphism on B(X) multiplied by a complex number λ satisfying λk-1 = 1. Let A be avon Neumann algebra andB be a Banach algebra, it is also shown that a bounded surjective linear map from A onto B is k-potent preserving if and only if it is a Jordan homomorphism multiplied by an invertible element with (k - 1)-th power I.

  16. Dmt and opioid peptides: a potent alliance.

    Science.gov (United States)

    Bryant, Sharon D; Jinsmaa, Yunden; Salvadori, Severo; Okada, Yoshio; Lazarus, Lawrence H

    2003-01-01

    The introduction of the Dmt (2',6'-dimethyl-L-tyrosine)-Tic pharmacophore into the design of opioid ligands produced an extraordinary family of potent delta-opioid receptor antagonists and heralded a new phase in opioid research. First reviewed extensively in 1998, the incorporation of Dmt into a diverse group of opioid molecules stimulated the opioid field leading to the development of unique analogues with remarkable properties. This overview will document the crucial role played by this residue in the proliferation of opioid peptides with high receptor affinity (K(i) equal to or less than 1 nM) and potent bioactivity. The discussion will include the metamorphosis between delta-opioid receptor antagonists to delta-agonists based solely on subtle structural changes at the C-terminal region of the Dmt-Tic pharmacophore as well as their behavior in vivo. Dmt may be considered promiscuous due to the acquisition of potent mu-agonism by dermorphin and endomorphin derivatives as well as by a unique class of opioidmimetics containing two Dmt residues separated by alkyl or pyrazinone linkers. Structural studies on the Dmt-Tic compounds were enhanced tremendously by x-ray diffraction data for three potent and biologically diverse Dmt-Tic opioidmimetics that led to the development of pharmacophores for both delta-opioid receptor agonists and antagonists. Molecular modeling studies of other unique Dmt opioid analogues illuminated structural differences between delta- and mu-receptor ligand interactions. The future of these compounds as therapeutic applications for various medical syndromes including the control of cancer-associated pain is only a matter of time and perseverance.

  17. Parallel screening of drug-like natural compounds using Caco-2 cell permeability QSAR model with applicability domain, lipophilic ligand efficiency index and shape property: A case study of HIV-1 reverse transcriptase inhibitors

    Science.gov (United States)

    Patel, Rikin D.; Kumar, Sivakumar Prasanth; Patel, Chirag N.; Shankar, Shetty Shilpa; Pandya, Himanshu A.; Solanki, Hitesh A.

    2017-10-01

    The traditional drug design strategy centrally focuses on optimizing binding affinity with the receptor target and evaluates pharmacokinetic properties at a later stage which causes high rate of attrition in clinical trials. Alternatively, parallel screening allows evaluation of these properties and affinity simultaneously. In a case study to identify leads from natural compounds with experimental HIV-1 reverse transcriptase (RT) inhibition, we integrated various computational approaches including Caco-2 cell permeability QSAR model with applicability domain (AD) to recognize drug-like natural compounds, molecular docking to study HIV-1 RT interactions and shape similarity analysis with known crystal inhibitors having characteristic butterfly-like model. Further, the lipophilic properties of the compounds refined from the process with best scores were examined using lipophilic ligand efficiency (LLE) index. Seven natural compound hits viz. baicalien, (+)-calanolide A, mniopetal F, fagaronine chloride, 3,5,8-trihydroxy-4-quinolone methyl ether derivative, nitidine chloride and palmatine, were prioritized based on LLE score which demonstrated Caco-2 well absorption labeling, encompassment in AD structural coverage, better receptor affinity, shape adaptation and permissible AlogP value. We showed that this integrative approach is successful in lead exploration of natural compounds targeted against HIV-1 RT enzyme.

  18. Advances in research of non-peptide small-molecule CCR5 antagonists%非肽类小分子趋化因子受体5拮抗剂的研究进展

    Institute of Scientific and Technical Information of China (English)

    姚虎; 冯建科; 韦弢; 刘瑞江

    2011-01-01

    趋化因子受体5(CCR5)属于G蛋白偶联受体超家族,是HIV感染早期介导病毒进入机体的主要辅助受体.CCR5拮抗剂已经成为一类重要的抗HIV病毒药物,主要包括趋化因子衍生物、非肽类小分子化合物、单克隆抗体、肽类化合物等4类.目前,全世界各大医药公司和研究机构纷纷研发了许多高选择性、活性强、生物利用度高的非肽类小分子CCR5拮抗剂,其中Maraviroc在2007年被FDA批准上市,还有一些目前已经进入临床试验阶段.文中对1999年到2009年10年间文献报道的相关非肽类小分子CCR5拮抗剂进行了综述.%CCR5, a membrane protein on cell surface, is a member of the G protein-coupled receptor superfamily and one of the major co-receptors for HIV-1 infection.CCR5 antagonists as viral entry inhibitors have recently emerged as an important class of anti-HIV medicines.Antagonists of CCR5 include following 4 types: chemokine derivatives, small molecule non-peptide compounds, monoclonal antibodies and peptides.In recent years,the major pharmaceutical companies and research institutions have developed a number of CCR5 antagonists with high selectivity, strong activity and a good bioavailability.Maraviroc was approved by FDA in 2007.The others have been under clinical trials.In this article, the literature from 1999 to 2009 related to non-peptide small-molecule CCR5 antagonists is reviewed.

  19. Standardization of the potentizing machine and quantification of impact of potentization

    Directory of Open Access Journals (Sweden)

    Rajesh Shah

    2016-01-01

    Since ten strokes are given, torque applied at every potency is calculated as 40.43. Conclusion: Necessity for the documentation of force parameters used in the process of potentization has been identified, and a tool is developed to demonstrate it.

  20. Which potent opioid? Important criteria for selection.

    Science.gov (United States)

    Bovill, J G

    1987-05-01

    Opioids remain the drugs of choice for the treatment of severe pain. In recent years several new potent opioids have become available for clinical use. These newer drugs are generally safer than the older morphine-like compounds and their differing pharmacological and pharmacokinetic properties allow the physician to choose an appropriate drug according to the clinical situation and need of an individual patient. These drugs are classified according to their activity at the opioid receptors. The opioid agonists produce their pharmacological effect by an almost exclusive action at mu-receptors. The agonist-antagonist group are kappa-receptor agonists and either competitive antagonists at the mu-receptor or weak mu-agonists. The use of the potent opioid agonists, because of their potential for causing respiratory depression, is restricted to hospitals. Fentanyl, the oldest drug of this class, is extensively used as a supplement to general anaesthesia, or in high doses as a 'complete' anaesthetic for patients undergoing cardiac surgery. Alfentanil and sufentanil are newer fentanyl derivatives. Alfentanil is unique in having a very short elimination half-life. This is a particular advantage during short operations and for day-case surgery. For longer operations alfentanil can be given as a continuous infusion to supplement nitrous oxide anaesthesia. Sufentanil is about 10 times more potent than fentanyl and is more rapidly eliminated. Initial reports suggest that it may be more effective than fentanyl as an anaesthetic supplement and that recovery may be more rapid. Both sufentanil and alfentanil are also used in cardiac anaesthesia. The newer agonist-antagonist opioids, butorphanol, nalbuphine and buprenorphine, have largely replaced pentazocine in clinical practice. Unlike pentazocine, they cause a low incidence of dysphoric side effects. Like the pure agonists, they cause respiratory depression; however, in contrast to the pure agonists this is not dose related

  1. Epistatic mutations in PUMA BH3 drive an alternate binding mode to potently and selectively inhibit anti-apoptotic Bfl-1

    Energy Technology Data Exchange (ETDEWEB)

    Jenson, Justin M.; Ryan, Jeremy A.; Grant, Robert A.; Letai, Anthony; Keating, Amy E. (DFCI); (MIT)

    2017-06-08

    Overexpression of anti-apoptotic Bcl-2 family proteins contributes to cancer progression and confers resistance to chemotherapy. Small molecules that target Bcl-2 are used in the clinic to treat leukemia, but tight and selective inhibitors are not available for Bcl-2 paralog Bfl-1. Guided by computational analysis, we designed variants of the native BH3 motif PUMA that are > 150-fold selective for Bfl-1 binding. The designed peptides potently trigger disruption of the mitochondrial outer membrane in cells dependent on Bfl-1, but not in cells dependent on other anti-apoptotic homologs. High-resolution crystal structures show that designed peptide FS2 binds Bfl-1 in a shifted geometry, relative to PUMA and other binding partners, due to a set of epistatic mutations. FS2 modified with an electrophile reacts with a cysteine near the peptide-binding groove to augment specificity. Designed Bfl-1 binders provide reagents for cellular profiling and leads for developing enhanced and cell-permeable peptide or small-molecule inhibitors.

  2. Strategies for preventing occupational exposure to potent compounds.

    Science.gov (United States)

    Calhoun, Dean M; Coler, Angela B; Nieusma, Joe L

    2011-02-01

    Occupational exposure to active pharmaceutical ingredients in a manufacturing or laboratory environmental can cause unintended health effects in workers handling these compounds. Occupational health professionals in the pharmaceutical industry have responded to this hazard recognition by employing strategies for the risk evaluation and management of potent APIs, otherwise known by the term 'potent compounds'. The purpose of this paper is to provide an overview of the necessary strategy components for preventing occupational exposure to potent compounds.

  3. Synthesis, biological evaluation and molecular modeling of 1-oxa-4-thiaspiro- and 1,4-dithiaspiro[4.5]decane derivatives as potent and selective 5-HT1A receptor agonists.

    Science.gov (United States)

    Franchini, Silvia; Manasieva, Leda Ivanova; Sorbi, Claudia; Battisti, Umberto M; Fossa, Paola; Cichero, Elena; Denora, Nunzio; Iacobazzi, Rosa Maria; Cilia, Antonio; Pirona, Lorenza; Ronsisvalle, Simone; Aricò, Giuseppina; Brasili, Livio

    2017-01-05

    Recently, 1-(1,4-dioxaspiro[4,5]dec-2-ylmethyl)-4-(2-methoxyphenyl)piperazine (1) was reported as a potent 5-HT1AR agonist with a moderate 5-HT1AR selectivity. In an extension of this work a series of derivatives of 1, obtained by combining different heterocyclic rings with a more flexible amine chain, was synthesized and tested for binding affinity and activity at 5-HT1AR and α1 adrenoceptors. The results led to the identification of 14 and 15 as novel 5-HT1AR partial agonists, the first being outstanding for selectivity (5-HT1A/α1d = 80), the latter for potency (pD2 = 9.58) and efficacy (Emax = 74%). Theoretical studies of ADME properties shows a good profile for the entire series and MDCKII-MDR1 cells permeability data predict a good BBB permeability of compound 15, which possess a promising neuroprotective activity. Furthermore, in mouse formalin test, compound 15 shows a potent antinociceptive activity suggesting a new strategy for pain control.

  4. A Novel Small Molecule, LLL12, Inhibits STAT3 Phosphorylation and Activities and Exhibits Potent Growth-Suppressive Activity in Human Cancer Cells

    Directory of Open Access Journals (Sweden)

    Li Lin

    2010-01-01

    Full Text Available Constitutive activation of signal transducer and activator of transcription 3 (STAT3 signaling is frequently detected in cancer, promoting its emergence as a promising target for cancer treatment. Inhibiting constitutive STAT3 signaling represents a potential therapeutic approach. We used structure-based design to develop a nonpeptide, cell-permeable, small molecule, termed as LLL12, which targets STAT3. LLL12 was found to inhibit STAT3 phosphorylation (tyrosine 705 and induce apoptosis as indicated by the increases of cleaved caspase-3 and poly (ADP-ribose polymerase in various breast, pancreatic, and glioblastoma cancer cell lines expressing elevated levels of STAT3 phosphorylation. LLL12 could also inhibit STAT3 phosphorylation induced by interleukin-6 in MDA-MB-453 breast cancer cells. The inhibition of STAT3 by LLL12 was confirmed by the inhibition of STAT3 DNA binding activity and STAT3-dependent transcriptional luciferase activity. Downstream targets of STAT3, cyclin D1, Bcl-2, and survivin were also downregulated by LLL12 at both protein and messenger RNA levels. LLL12 is a potent inhibitor of cell viability, with half-maximal inhibitory concentrations values ranging between 0.16 and 3.09 µM, which are lower than the reported JAK2 inhibitor WP1066 and STAT3 inhibitor S3I-201 in six cancer cell lines expressing elevated levels of STAT3 phosphorylation. In addition, LLL12 inhibits colony formation and cell migration and works synergistically with doxorubicin and gemcitabine. Furthermore, LLL12 demonstrated a potent inhibitory activity on breast and glioblastoma tumor growth in a mouse xenograft model. Our results indicate that LLL12 may be a potential therapeutic agent for human cancer cells expressing constitutive STAT3 signaling.

  5. POTENT Reconstruction from Mark III Velocities

    Science.gov (United States)

    Dekel, A.; Eldar, A.; Kolatt, T.; Yahil, A.; Willick, J. A.; Faber, S. M.; Courteau, S.; Burstein, D.

    1999-09-01

    We present an improved version of the POTENT method for reconstructing the cosmological velocity and mass density fields from radial peculiar velocities, test it with mock catalogs, and apply it to the Mark III Catalog of Galaxy Peculiar Velocities. The method is improved in several ways: (1) the inhomogeneous Malmquist bias is reduced by grouping and corrected statistically in either forward or inverse analyses of inferred distances, (2) the smoothing into a radial velocity field is optimized such that window and sampling biases are reduced, (3) the density field is derived from the velocity field using an improved weakly nonlinear approximation in Eulerian space, and (4) the computational errors are made negligible compared to the other errors. The method is carefully tested and optimized using realistic mock catalogs based on an N-body simulation that mimics our cosmological neighborhood, and the remaining systematic and random errors are evaluated quantitatively. The Mark III catalog, with ~3300 grouped galaxies, allows a reliable reconstruction with fixed Gaussian smoothing of 10-12 h-1 Mpc out to ~60 h-1 Mpc and beyond in some directions. We present maps of the three-dimensional velocity and mass-density fields and the corresponding errors. The typical systematic and random errors in the density fluctuations inside 40 h-1 Mpc are +/-0.13 and +/-0.18 (for Ω=1). In its gross features, the recovered mass distribution resembles the galaxy distribution in redshift surveys and the mass distribution in a similar POTENT analysis of a complementary velocity catalog (SFI), including such features as the Great Attractor, Perseus-Pisces, and the large void in between. The reconstruction inside ~40 h-1 Mpc is not affected much by a revised calibration of the distance indicators (VM2, tailored to match the velocities from the IRAS 1.2 Jy redshift survey). The volume-weighted bulk velocity within the sphere of radius 50 h-1 Mpc about the Local Group is V50=370+/-110 km s-1

  6. ANTIMICROBIAL POTENT OXAZINE-2-AMINE DERIVATIVES

    Directory of Open Access Journals (Sweden)

    GANESAMOORTHY THIRUNARAYANAN

    2016-07-01

    Full Text Available Objective: To synthesize thirteen effective microbial potent oxazine-2-amine derivatives and evaluate the antimicrobial activities of these compounds. Material and methods: The solvent-free solid fly-ash: H2SO4 catalyzed cyclization of 4-bromo-1-naphthyl chalcones and urea under microwave irradiation technique was utilized for the synthesis of oxazine derivatives. The synthesized oxazines were characterized by their physical constants and spectroscopic data. The Bauer-Kirby disc-diffusion method of measurement of zone of inhibition was used for evaluation antimicrobial activity of synthesized oxazines. Results: The cyclization was effective and this reaction gave more than 80% yield. The catalyst was reused up to five times consecutively without appreciable decreasing of yield. All compounds were active against their microbial strains. Conclusions: This solvent-free synthetic method was effective for the synthesis of oxazine derivatives. The amino, dimethylamino, halogens, methoxy and methyl substituted oxazines shows significant antibacterial activity. Chloro, hydroxy and nitro substituted oxazine derivative have shown significant antifungal activity.

  7. Substituted cyclobutane derivatives as non-peptidic GLP-1 receptor agonists%取代环丁烷结构的非肽类胰高血糖素样肽-1受体激动剂

    Institute of Scientific and Technical Information of China (English)

    刘青; 何敏; 周彩红; 王明伟

    2012-01-01

    应用胰高血糖素样肽-l (glucagon-like peptide-1,GLP-1)及其类似物治疗2型糖尿病是代谢性疾病研究领域近年来的热点,尤其是胰高血糖素样肽-1独特的作用机制倍受业界的关注.它能同时作用于2型糖尿病的多个发病环节,在有效降低血糖的同时,避免低血糖的发生并能减轻体重.但这类药物因其多肽性质而存在诸多的使用限制(如需反复注射).简要介绍一类取代环丁烷结构的新型非肽类胰高血糖素样肽-1受体小分子激动剂的发现过程、基本药理学特征和体内抗糖尿病和抗肥胖症效应.%Application of glucagon-like peptide-1 (GLP-1) to treat type 2 diabetes has become a focal point in the study of metabolic diseases in recent years. Of particular interest is the unique mechanisms of action relative to GLP-1. It exerts multiple effects on the pathogenesis of type 2 diabetes. While effectively lowering blood glucose levels, it does not cause hypoglycemia but reduces body weight. However, GLP-1 and its peptidic mimetics require frequent injections that limits their wide use. This paper briefly reviews the discovery and pharmacological characterization of a class of novel cyclobutane derivatives as non-peptidic GLP-1 receptor agonists including in vivo efficacies on diabetes and obesity.

  8. Carbapenems: a potent class of antibiotics.

    Science.gov (United States)

    Nicolau, David P

    2008-01-01

    The purpose of this review is to assess the relative strengths and weaknesses of individual members of the carbapenem class of antibiotics. Clinical trials and review articles were identified from a Medline search (1979 - July 2006), in addition to, reference citations from identified publications, abstracts from the Interscience Conferences on Antimicrobial Agents and Chemotherapy and the 12th International Congress on Infectious Disease, and package inserts. Articles in English were reviewed, with emphasis on those containing efficacy or safety data. Carbapenems bind to critical penicillin-binding proteins, disrupting the growth and structural integrity of bacterial cell walls. They provide enhanced anaerobic and Gram-negative coverage as compared with other beta-lactams and their stability against extended-spectrum beta-lactamases (ESBLs) makes them an effective treatment option. The most common adverse effects are infusion-site complications and gastrointestinal distress. Ertapenem has limited efficacy against non-fermenting, Gram-negative bacteria, restricting its use to community-acquired infections. Imipenem is slightly more effective against Gram-positive organisms and meropenem slightly more effective against Gram-negative organisms. However, both have broad-spectrum activity, including non-fermenting, Gram-negative bacteria. Among non-fermenting, Gram-negatives, resistance to imipenem in particular is increasing. Doripenem is in late-stage clinical development and combines the broad-spectrum coverage of imipenem and meropenem, and more potent activity against Pseudomonas aeruginosa. Due to the increasing challenges represented by ESBLs and multi-drug resistant organisms, the carbapenems are assuming a greater role in the treatment of serious infections. Imipenem and meropenem are presently available and have been shown to be effective against nosocomial infections. Doripenem is an investigational carbapenem that has completed Phase III clinical trials and

  9. Sifuvirtide, a potent HIV fusion inhibitor peptide

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Rui-Rui; Yang, Liu-Meng; Wang, Yun-Hua [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China); Pang, Wei [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China); Department of Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080 (China); Tam, Siu-Cheung [Department of Physiology, Chinese University of Hong Kong, Shatin, N.T., Hong Kong (China); Tien, Po [Department of Molecular Virology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100080 (China); Zheng, Yong-Tang, E-mail: zhengyt@mail.kiz.ac.cn [Key Laboratory of Animal Models and Human Disease Mechanisms, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223 (China)

    2009-05-08

    Enfuvirtide (ENF) is currently the only FDA approved HIV fusion inhibitor in clinical use. Searching for more drugs in this category with higher efficacy and lower toxicity seems to be a logical next step. In line with this objective, a synthetic peptide with 36 amino acid residues, called Sifuvirtide (SFT), was designed based on the crystal structure of gp41. In this study, we show that SFT is a potent anti-HIV agent with relatively low cytotoxicity. SFT was found to inhibit replication of all tested HIV strains. The effective concentrations that inhibited 50% viral replication (EC{sub 50}), as determined in all tested strains, were either comparable or lower than benchmark values derived from well-known anti-HIV drugs like ENF or AZT, while the cytotoxic concentrations causing 50% cell death (CC{sub 50}) were relatively high, rendering it an ideal anti-HIV agent. A GST-pull down assay was performed to confirm that SFT is a fusion inhibitor. Furthermore, the activity of SFT on other targets in the HIV life cycle was also investigated, and all assays showed negative results. To further understand the mechanism of action of HIV peptide inhibitors, resistant variants of HIV-1{sub IIIB} were derived by serial virus passage in the presence of increasing doses of SFT or ENF. The results showed that there was cross-resistance between SFT and ENF. In conclusion, SFT is an ideal anti-HIV agent with high potency and low cytotoxicity, but may exhibit a certain extent of cross-resistance with ENF.

  10. Intermittent treatment with parathyroid hormone (PTH) as well as a non-peptide small molecule agonist of the PTH1 receptor inhibits adipocyte differentiation in human bone marrow stromal cells.

    Science.gov (United States)

    Rickard, David J; Wang, Fei-Lan; Rodriguez-Rojas, Ana-Maria; Wu, Zining; Trice, Wen J; Hoffman, Sandra J; Votta, Bartholomew; Stroup, George B; Kumar, Sanjay; Nuttall, Mark E

    2006-12-01

    Whereas continuous PTH infusion increases bone resorption and bone loss, intermittent PTH treatment stimulates bone formation, in part, via reactivation of quiescent bone surfaces and reducing osteoblast apoptosis. We investigated the possibility that intermittent and continuous PTH treatment also differentially regulates osteogenic and adipocytic lineage commitment of bone marrow stromal progenitor/mesenchymal stem cells (MSC). The MSC were cultured under mildly adipogenic conditions in medium supplemented with dexamethasone, insulin, isobutyl-methylxanthine and troglitazone (DIIT), and treated with 50 nM human PTH(1-34) for either 1 h/day or continuously (PTH replenished every 48 h). After 6 days, cells treated with PTH for 1 h/day retained their normal fibroblastic appearance whereas those treated continuously adopted a polygonal, irregular morphology. After 12-18 days numerous lipid vacuole and oil red O-positive adipocytes had developed in cultures treated with DIIT alone, or with DIIT and continuous PTH. In contrast, adipocyte number was reduced and alkaline phosphatase staining increased in the cultures treated with DIIT and 1 h/day PTH, indicating suppression of adipogenesis and possible promotion of early osteoblastic differentiation. Furthermore, intermittent but not continuous PTH treatment suppressed markers of differentiated adipocytes such as mRNA expression of lipoprotein lipase and PPARgamma as well as glycerol 3-phosphate dehydrogenase activity. All of these effects of intermittent PTH were also produced by a 1 h/day treatment with AH3960 (30 microM), a small molecule, non-peptide agonist of the PTH1 receptor. AH3960, like PTH, activates both the cAMP and calcium signaling pathways. Treatment with the adenylyl cyclase activator forskolin for 1 h/day, mimicked the anti-adipogenic effect of intermittent PTH, whereas pretreatment with the protein kinase-A inhibitor H89 prior to intermittent PTH resulted in almost complete conversion to adipocytes. In

  11. Empowerment as a Potent Tool for Alleviating Poverty and Stress ...

    African Journals Online (AJOL)

    Empowerment as a Potent Tool for Alleviating Poverty and Stress Among Nigerian ... Invariably, poor rural women with little political, economic education and ... insufficient nutrition and children being denied the right to enjoy healthy diet that ...

  12. Novel indole sulfides as potent HIV-1 NNRTIs.

    Science.gov (United States)

    Brigg, Siobhan; Pribut, Nicole; Basson, Adriaan E; Avgenikos, Moscos; Venter, Reinhardt; Blackie, Margaret A; van Otterlo, Willem A L; Pelly, Stephen C

    2016-03-15

    In a previous communication we described a series of indole based NNRTIs which were potent inhibitors of HIV replication, both for the wild type and K103N strains of the virus. However, the methyl ether functionality on these compounds, which was crucial for potency, was susceptible to acid promoted indole assisted SN1 substitution. This particular problem did not bode well for an orally bioavailable drug. Here we describe bioisosteric replacement of this problematic functional group, leading to a series of compounds which are potent inhibitors of HIV replication, and are acid stable.

  13. Novel pyrazolopyrimidines as highly potent B-Raf inhibitors.

    Science.gov (United States)

    Di Grandi, Martin J; Berger, Dan M; Hopper, Darrin W; Zhang, Chunchun; Dutia, Minu; Dunnick, Alejandro L; Torres, Nancy; Levin, Jeremy I; Diamantidis, George; Zapf, Christoph W; Bloom, Jonathan D; Hu, YongBo; Powell, Dennis; Wojciechowicz, Donald; Collins, Karen; Frommer, Eileen

    2009-12-15

    A novel series of pyrazolo[1,5-a]pyrimidines bearing a 3-hydroxyphenyl group at C(3) and substituted tropanes at C(7) have been identified as potent B-Raf inhibitors. Exploration of alternative functional groups as a replacement for the C(3) phenol demonstrated indazole to be an effective isostere. Several compounds possessing substituted indazole residues, such as 4e, 4p, and 4r, potently inhibited cell proliferation at submicromolar concentrations in the A375 and WM266 cell lines, and the latter two compounds also exhibited good therapeutic indices in cells.

  14. Identification of a potent endothelium-derived angiogenic factor

    DEFF Research Database (Denmark)

    Jankowski, Vera; Tölle, Markus; Tran, Thi Nguyet Anh

    2013-01-01

    The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U) from the secretome of human endothelial cells. The angiogenic effect of the endothelia...

  15. Total synthesis of the potent microtubule-stabilizing agent (+)-discodermolide.

    Science.gov (United States)

    Harried, Scott S; Lee, Christopher P; Yang, Ge; Lee, Tony I H; Myles, David C

    2003-08-22

    The total synthesis of the potent microtubule-stabilizing, antimitotic agent (+)-discodermolide is described. The convergent synthetic strategy takes advantage of the diastereoselective alkylation of a ketone enolate to establish the key C15-C16 bond. The synthesis is amenable to preparation of gram-scale quantities of (+)-discodermolide and analogues.

  16. Tricin from a malagasy connaraceous plant with potent antihistaminic activity.

    Science.gov (United States)

    Kuwabara, Hidenori; Mouri, Kyoko; Otsuka, Hideaki; Kasai, Ryoji; Yamasaki, Kazuo

    2003-09-01

    The bioassay-guided separation of a Malagasy plant, Agelaea pentagyna, led to the isolation of a flavonoid, tricin (1), with potent inhibitory activity toward exocytosis from antigen-stimulated rat leukemia basophils (RBL-2H3). The structure-activity relationships among structurally related natural and synthetic flavonoids are also discussed.

  17. Potent pyrrolidine- and piperidine-based BACE-1 inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Iserloh, U.; Wu, Y.; Cumming, J.N.; Pan, J.; Wang, L.Y.; Stamford, A.W.; Kennedy, M.E.; Kuvelkar, R.; Chen, X.; Parker, E.M.; Strickland, C.; Voigt, J. (Schering-Plough)

    2008-08-18

    Based on lead compound 1 identified from the patent literature, we developed novel patentable BACE-1 inhibitors by introducing a cyclic amine scaffold. Extensive SAR studies on both pyrrolidines and piperidines ultimately led to inhibitor 2f, one of the most potent inhibitors synthesized to date. The discovery and development of novel BACE-1 inhibitors incorporating a cyclic amine scaffold is described.

  18. Extensive screening for herbal extracts with potent antioxidant properties.

    Science.gov (United States)

    Niwano, Yoshimi; Saito, Keita; Yoshizaki, Fumihiko; Kohno, Masahiro; Ozawa, Toshihiko

    2011-01-01

    This paper summarizes our research for herbal extracts with potent antioxidant activity obtained from a large scale screening based on superoxide radical (O(2) (•-)) scavenging activity followed by characterization of antioxidant properties. Firstly, scavenging activity against O(2) (•-) was extensively screened from ethanol extracts of approximately 1000 kinds of herbs by applying an electron spin resonance (ESR)-spin trapping method, and we chose four edible herbal extracts with prominently potent ability to scavenge O(2) (•-). They are the extracts from Punica granatum (Peel), Syzygium aromaticum (Bud), Mangifera indica (Kernel), and Phyllanthus emblica (Fruit). These extracts were further examined to determine if they also scavenge hydroxyl radical ((•)OH), by applying the ESR spin-trapping method, and if they have heat resistance as a desirable characteristic feature. Experiments with the Fenton reaction and photolysis of H(2)O(2) induced by UV irradiation demonstrated that all four extracts have potent ability to directly scavenge (•)OH. Furthermore, the scavenging activities against O(2) (•-) and (•)OH of the extracts of P. granatum (peel), M. indica (kernel) and P. emblica (fruit) proved to be heat-resistant.The results of the review might give useful information when choosing a potent antioxidant as a foodstuff. For instance, the four herbal extracts chosen from extensive screening possess desirable antioxidant properties. In particular, the extracts of the aforementioned three herbs are expected to be suitable for food processing in which thermal devices are used, because of their heat resistance.

  19. Rat full term amniotic fluid harbors highly potent stem cells.

    Science.gov (United States)

    Mun-Fun, Hoo; Ferdaos, Nurfarhana; Hamzah, Siti Nurusaadah; Ridzuan, Noridzzaida; Hisham, Nurul Afiqah; Abdullah, Syahril; Ramasamy, Rajesh; Cheah, Pike See; Thilakavathy, Karrupiah; Yazid, Mohd Nazri; Nordin, Norshariza

    2015-10-01

    Amniotic fluid stem cells (AFSCs) are commonly isolated from mid-term amniotic fluid (AF) of animals and human collected via an invasive technique, amniocentesis. Alternatively, AFSCs could be collected at full-term. However, it is unclear whether AFSCs are present in the AF at full term. Here, we aimed to isolate and characterize stem cells isolated from AF of full term pregnant rats. Three stem cell lines have been established following immuno-selection against the stem cell marker, c-kit. Two of the new lines expressed multiple markers of pluripotency until more than passage 90. Further, they spontaneously differentiated into derivatives of the three primary germ layers through the formation of good quality embryoid bodies (EBs), and can be directly differentiated into neural lineage. Their strong stemness and potent neurogenic properties highlight the presence of highly potent stem cells in AF of full-term pregnancies, which could serve as a potential source of stem cells for regenerative medicine.

  20. Discovery of potent, selective chymase inhibitors via fragment linking strategies.

    Science.gov (United States)

    Taylor, Steven J; Padyana, Anil K; Abeywardane, Asitha; Liang, Shuang; Hao, Ming-Hong; De Lombaert, Stéphane; Proudfoot, John; Farmer, Bennett S; Li, Xiang; Collins, Brandon; Martin, Leslie; Albaugh, Daniel R; Hill-Drzewi, Melissa; Pullen, Steven S; Takahashi, Hidenori

    2013-06-13

    Chymase plays an important and diverse role in the homeostasis of a number of cardiovascular processes. Herein, we describe the identification of potent, selective chymase inhibitors, developed using fragment-based, structure-guided linking and optimization techniques. High-concentration biophysical screening methods followed by high-throughput crystallography identified an oxindole fragment bound to the S1 pocket of the protein exhibiting a novel interaction pattern hitherto not observed in chymase inhibitors. X-ray crystallographic structures were used to guide the elaboration/linking of the fragment, ultimately leading to a potent inhibitor that was >100-fold selective over cathepsin G and that mitigated a number of liabilities associated with poor physicochemical properties of the series it was derived from.

  1. Pyrrole-3-carboxamides as potent and selective JAK2 inhibitors.

    Science.gov (United States)

    Brasca, Maria Gabriella; Nesi, Marcella; Avanzi, Nilla; Ballinari, Dario; Bandiera, Tiziano; Bertrand, Jay; Bindi, Simona; Canevari, Giulia; Carenzi, Davide; Casero, Daniele; Ceriani, Lucio; Ciomei, Marina; Cirla, Alessandra; Colombo, Maristella; Cribioli, Sabrina; Cristiani, Cinzia; Della Vedova, Franco; Fachin, Gabriele; Fasolini, Marina; Felder, Eduard R; Galvani, Arturo; Isacchi, Antonella; Mirizzi, Danilo; Motto, Ilaria; Panzeri, Achille; Pesenti, Enrico; Vianello, Paola; Gnocchi, Paola; Donati, Daniele

    2014-09-01

    We report herein the discovery, structure guided design, synthesis and biological evaluation of a novel class of JAK2 inhibitors. Optimization of the series led to the identification of the potent and orally bioavailable JAK2 inhibitor 28 (NMS-P953). Compound 28 displayed significant tumour growth inhibition in SET-2 xenograft tumour model, with a mechanism of action confirmed in vivo by typical modulation of known biomarkers, and with a favourable pharmacokinetic and safety profile.

  2. Daidzin: a potent, selective inhibitor of human mitochondrial aldehyde dehydrogenase.

    OpenAIRE

    Keung, W M; Vallee, B L

    1993-01-01

    Human mitochondrial aldehyde dehydrogenase (ALDH-I) is potently, reversibly, and selectively inhibited by an isoflavone isolated from Radix puerariae and identified as daidzin, the 7-glucoside of 4',7-dihydroxyisoflavone. Kinetic analysis with formaldehyde as substrate reveals that daidzin inhibits ALDH-I competitively with respect to formaldehyde with a Ki of 40 nM, and uncompetitively with respect to the coenzyme NAD+. The human cytosolic aldehyde dehydrogenase isozyme (ALDH-II) is nearly 3...

  3. Potent cardiovascular actions of homologous adrenomedullins in eels.

    Science.gov (United States)

    Nobata, Shigenori; Ogoshi, Maho; Takei, Yoshio

    2008-05-01

    Adrenomedullin (AM), known as a multifunctional hormone in mammals, forms a unique family of five paralogous peptides in teleost fish. To examine their cardiovascular effects using homologous AMs in eels, we isolated cDNAs encoding four eel AMs, and named AM1 (ortholog of mammalian AM), AM2, AM3 (paralog of AM2 generated only in teleost lineage), and AM5 according to the known teleost AM sequences. Unlike pufferfish, not only AM1 but AM2/3 and AM5 were expressed ubiquitously in various eel tissues. Synthetic mature AM1, AM2, and AM5 exhibited vasodepressor effects after intra-arterial injections, and the effects were more potent at dorsal aorta than at ventral aorta. This indicates that AMs preferentially act on peripheral resistance vessels rather than on branchial arterioles. The potency was in the order of AM2 = AM5 > AM1 in both freshwater (FW) and seawater (SW) eels, which is different from the result of mammals in which AM1 is as potent as, or more potent than, AM2 when injected peripherally. The minimum effective dose of AM2 and AM5 in eels was 1/10 that of AM1 in mammals. The hypotension reached 50% at 1.0 nmol/kg of AM2 and AM5, which is much greater than atrial natriuretic peptide (20%), another potent vasodepressor hormone. Even with such hypotension, AMs did not change heart rate in eels. In addition, AM1 increased blood pressure at ventral aorta and dorsal aorta immediately after an initial hypotension at 5.0 nmol/kg, but not with AM2 and AM5. These data strongly suggest that specific receptors for AM2 and AM5 exist in eels, which differ from the AM1 receptors identified in mammals.

  4. Daidzin: a potent, selective inhibitor of human mitochondrial aldehyde dehydrogenase.

    Science.gov (United States)

    Keung, W M; Vallee, B L

    1993-02-15

    Human mitochondrial aldehyde dehydrogenase (ALDH-I) is potently, reversibly, and selectively inhibited by an isoflavone isolated from Radix puerariae and identified as daidzin, the 7-glucoside of 4',7-dihydroxyisoflavone. Kinetic analysis with formaldehyde as substrate reveals that daidzin inhibits ALDH-I competitively with respect to formaldehyde with a Ki of 40 nM, and uncompetitively with respect to the coenzyme NAD+. The human cytosolic aldehyde dehydrogenase isozyme (ALDH-II) is nearly 3 orders of magnitude less sensitive to daidzin inhibition. Daidzin does not inhibit human class I, II, or III alcohol dehydrogenases, nor does it have any significant effect on biological systems that are known to be affected by other isoflavones. Among more than 40 structurally related compounds surveyed, 12 inhibit ALDH-I, but only prunetin and 5-hydroxydaidzin (genistin) combine high selectivity and potency, although they are 7- to 15-fold less potent than daidzin. Structure-function relationships have established a basis for the design and synthesis of additional ALDH inhibitors that could both be yet more potent and specific.

  5. Heterogeneous nucleation on potent spherical substrates during solidification

    Energy Technology Data Exchange (ETDEWEB)

    Ma Qian [BCAST - Brunel Centre for Advanced Solidification Technology, Brunel University, West London UB8 3PH (United Kingdom)]. E-mail: ma.qian@brunel.ac.uk

    2007-02-15

    For a spherical-cap nucleus to become a 'transformation nucleus', the linear dimension (d) of the flat substrate must exceed the critical nucleus size (2r *). This Turnbull criterion (d {>=} 2r *) defines a minimum undercooling for grain formation on, and effective inoculation with, flat nucleating substrates. However, for nucleation on potent substrates the spherical-cap model is no longer tenable. The free growth model has in general considered the growth of a two-dimensional nucleus on a potent flat substrate. Inspired by the particle-core structures observed in magnesium alloys after inoculation with nearly spherical zirconium particles, a model has been proposed, on the basis of an adsorption and surface diffusion mechanism, for heterogeneous nucleation and grain formation on potent spherical substrates of d {>=} 2r *. The critical undercooling required is found to be approximately the same as that defined by Turnbull's patch nucleation theory. The model shows excellent agreement with experiments compared from different perspectives.

  6. Tetrahydrohyperforin and octahydrohyperforin are two new potent inhibitors of angiogenesis.

    Directory of Open Access Journals (Sweden)

    Beatriz Martínez-Poveda

    Full Text Available BACKGROUND: We have previously shown that hyperforin, a phloroglucinol derivative found in St. John's wort, behaves as a potent anti-angiogenic compound. To identify the reactive group(s mainly involved in this anti-angiogenic effect, we have investigated the anti-angiogenic properties of a series of stable derivatives obtained by oxidative modification of the natural product. In addition, in the present work we have studied the role of the four carbonyl groups present in hyperforin by investigating the potential of some other chemically stable derivatives. METHODOLOGY/PRINCIPAL FINDINGS: The experimental procedures included the analysis of the effects of treatment of endothelial cells with these compounds in cell growth, cell viability, cell migration and zymographic assays, as well as the tube formation assay on Matrigel. Our study with hyperforin and eight derivatives shows that the enolized beta-dicarbonyl system contained in the structure of hyperforin has a dominant role in its antiangiogenic activity. On the other hand, two of the tested hyperforin derivatives, namely, tetrahydrohyperforin and octahydrohyperforin, behave as potent inhibitors of angiogenesis. Additional characterization of these compounds included a cell specificity study of their effects on cell growth, as well as the in vivo Matrigel plug assay. CONCLUSIONS/SIGNIFICANCE: These observations could be useful for the rational design and chemical synthesis of more effective hyperforin derivatives as anti-angiogenic drugs. Altogether, the results indicate that octahydrohyperforin is a more specific and slightly more potent antiangiogenic compound than hyperforin.

  7. Design of potent substrate-analogue inhibitors of canine renin

    Science.gov (United States)

    Hui, K. Y.; Siragy, H. M.; Haber, E.

    1992-01-01

    Through a systematic study of structure-activity relationships, we designed potent renin inhibitors for use in dog models. In assays against dog plasma renin at neutral pH, we found that, as in previous studies of rat renin inhibitors, the structure at the P2 position appears to be important for potency. The substitution of Val for His at this position increases potency by one order of magnitude. At the P3 position, potency appears to depend on a hydrophobic side chain that does not necessarily have to be aromatic. Our results also support the approach of optimizing potency in a renin inhibitor by introducing a moiety that promotes aqueous solubility (an amino group) at the C-terminus of the substrate analogue. In the design of potent dog plasma renin inhibitors, the influence of the transition-state residue 4(S)-amino-3(S)-hydroxy-5-cyclohexylpentanoic acid (ACHPA)-commonly used as a substitute for the scissile-bond dipeptide to boost potency-is not obvious, and appears to be sequence dependent. The canine renin inhibitor Ac-paF-Pro-Phe-Val-statine-Leu-Phe-paF-NH2 (compound 15; IC50 of 1.7 nM against dog plasma renin at pH 7.4; statine, 4(S)-amino-3(S)-hydroxy-6-methylheptanoic acid; paF, para-aminophenylalanine) had a potent hypotensive effect when infused intravenously into conscious, sodium-depleted, normotensive dogs. Also, compound 15 concurrently inhibited plasma renin activity and had a profound diuretic effect.

  8. Trigocherrierin A, a potent inhibitor of chikungunya virus replication.

    Science.gov (United States)

    Bourjot, Mélanie; Leyssen, Pieter; Neyts, Johan; Dumontet, Vincent; Litaudon, Marc

    2014-03-24

    Trigocherrierin A (1) and trigocherriolide E (2), two new daphnane diterpenoid orthoesters (DDOs), and six chlorinated analogues, trigocherrins A, B, F and trigocherriolides A-C, were isolated from the leaves of Trigonostemon cherrieri. Their structures were identified by mass spectrometry, extensive one- and two-dimensional NMR spectroscopy and through comparison with data reported in the literature. These compounds are potent and selective inhibitors of chikungunya virus (CHIKV) replication. Among the DDOs isolated, compound 1 exhibited the strongest anti-CHIKV activity (EC₅₀ = 0.6 ± 0.1 µM, SI = 71.7).

  9. microRNA-101 is a potent inhibitor of autophagy

    DEFF Research Database (Denmark)

    Frankel, Lisa B; Wen, Jiayu; Lees, Michael

    2011-01-01

    performed a functional screen in search of microRNAs (miRNAs), which regulate the autophagic flux in breast cancer cells. In this study, we identified the tumour suppressive miRNA, miR-101, as a potent inhibitor of basal, etoposide- and rapamycin-induced autophagy. Through transcriptome profiling, we...... identified three novel miR-101 targets, STMN1, RAB5A and ATG4D. siRNA-mediated depletion of these genes phenocopied the effect of miR-101 overexpression, demonstrating their importance in autophagy regulation. Importantly, overexpression of STMN1 could partially rescue cells from miR-101-mediated inhibition...

  10. Pyrazolopyridines as potent PDE4B inhibitors: 5-Heterocycle SAR

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Charlotte J.; Ballantine, Stuart P.; Coe, Diane M.; Cook, Caroline M.; Delves, Christopher J.; Dowle, Mike D.; Edlin, Chris D.; Hamblin, J. Nicole; Holman, Stuart; Johnson, Martin R.; Jones, Paul S.; Keeling, Sue E.; Kranz, Michael; Lindvall, Mika; Lucas, Fiona S.; Neu, Margarete; Solanke, Yemisi E.; Somers, Don O.; Trivedi, Naimisha A.; Wiseman, Joanne O. (GSK)

    2012-05-03

    Following the discovery of 4-(substituted amino)-1-alkyl-pyrazolo[3,4-b]pyridine-5-carboxamides as potent and selective phosphodiesterase 4B inhibitors, [Hamblin, J. N.; Angell, T.; Ballentine, S., et al. Bioorg. Med. Chem. Lett.2008, 18, 4237] the SAR of the 5-position was investigated further. A range of substituted heterocycles showed good potencies against PDE4. Optimisation using X-ray crystallography and computational modelling led to the discovery of 16, with sub-nM inhibition of LPS-induced TNF-{alpha} production from isolated human peripheral blood mononuclear cells.

  11. Discovery of a potent and selective GPR120 agonist.

    Science.gov (United States)

    Shimpukade, Bharat; Hudson, Brian D; Hovgaard, Christine Kiel; Milligan, Graeme; Ulven, Trond

    2012-05-10

    GPR120 is a receptor of unsaturated long-chain fatty acids reported to mediate GLP-1 secretion, insulin sensitization, anti-inflammatory, and anti-obesity effects and is therefore emerging as a new potential target for treatment of type 2 diabetes and metabolic diseases. Further investigation is however hindered by the lack of suitable receptor modulators. Screening of FFA1 ligands provided a lead with moderate activity on GPR120 and moderate selectivity over FFA1. Optimization led to the discovery of the first potent and selective GPR120 agonist.

  12. HU-444, a Novel, Potent Anti-Inflammatory, Nonpsychotropic Cannabinoid

    OpenAIRE

    Haj, Christeene G.; Sumariwalla, Percy F; Hanuš, Lumír; Kogan, Natalya M.; Yektin, Zhana; Mechoulam,Raphael; Feldmann, Mark; Gallily, Ruth

    2015-01-01

    Cannabidiol (CBD) is a component of cannabis, which does not cause the typical marijuana-type effects, but has a high potential for use in several therapeutic areas. In contrast to Δ9-tetrahydrocannabinol (Δ9-THC), it binds very weakly to the CB1 and CB2 cannabinoid receptors. It has potent activity in both in vitro and in vivo anti-inflammatory assays. Thus, it lowers the formation of tumor necrosis factor (TNF)-α, a proinflammatory cytokine, and was found to be an oral antiarthritic therape...

  13. New potent calcimimetics: II. Discovery of benzothiazole trisubstituted ureas.

    Science.gov (United States)

    Deprez, Pierre; Temal, Taoues; Jary, Hélène; Auberval, Marielle; Lively, Sarah; Guédin, Denis; Vevert, Jean-Paul

    2013-04-15

    Following the identification of trisubstituted ureas as a promising new chemical series of allosteric modulators of the calcium sensing receptor (CaSR), we further explored the SAR around the urea substitution, leading to the discovery of benzothiazole urea compound 13. This compound is a potent calcimimetic with an EC50=20 nM (luciferase assay). Evaluated in an in vivo model of chronic renal failure (short term and long term in 5/6 nephrectomized rats), benzothiazole urea 13 significantly decreased PTH levels after oral administration while keeping calcemia within the normal range.

  14. Trigocherrierin A, a Potent Inhibitor of Chikungunya Virus Replication

    Directory of Open Access Journals (Sweden)

    Mélanie Bourjot

    2014-03-01

    Full Text Available Trigocherrierin A (1 and trigocherriolide E (2, two new daphnane diterpenoid orthoesters (DDOs, and six chlorinated analogues, trigocherrins A, B, F and trigocherriolides A–C, were isolated from the leaves of Trigonostemon cherrieri. Their structures were identified by mass spectrometry, extensive one- and two-dimensional NMR spectroscopy and through comparison with data reported in the literature. These compounds are potent and selective inhibitors of chikungunya virus (CHIKV replication. Among the DDOs isolated, compound 1 exhibited the strongest anti-CHIKV activity (EC50 = 0.6 ± 0.1 µM, SI = 71.7.

  15. Potent antimalarial 4-pyridones with improved physico-chemical properties.

    Science.gov (United States)

    Bueno, José M; Manzano, Pilar; García, María C; Chicharro, Jesús; Puente, Margarita; Lorenzo, Milagros; García, Adolfo; Ferrer, Santiago; Gómez, Rubén M; Fraile, María T; Lavandera, José L; Fiandor, José M; Vidal, Jaume; Herreros, Esperanza; Gargallo-Viola, Domingo

    2011-09-15

    Antimalarial 4-pyridones are a novel class of inhibitors of the plasmodial mitochondrial electron transport chain targeting Cytochrome bc1 (complex III). In general, the most potent 4-pyridones are lipophilic molecules with poor solubility in aqueous media and low oral bioavailability in pre-clinical species from the solid dosage form. The strategy of introducing polar hydroxymethyl groups has enabled us to maintain the high levels of antimalarial potency observed for other more lipophilic analogues whilst improving the solubility and the oral bioavailability in pre-clinical species. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Adrenomedullin - new perspectives of a potent peptide hormone.

    Science.gov (United States)

    Schönauer, Ria; Els-Heindl, Sylvia; Beck-Sickinger, Annette G

    2017-02-02

    Adrenomedullin (ADM) is a 52-amino acid multifunctional peptide, which belongs to the calcitonin gene-related peptide (CGRP) superfamily of vasoactive peptide hormones. ADM exhibits a significant vasodilatory potential and plays a key role in various regulatory mechanisms, predominantly in the cardiovascular and lymphatic system. It exerts its effects by activation of the calcitonin receptor-like receptor associated with one of the receptor activity-modifying proteins 2 or 3. ADM was first isolated from human phaeochromocytoma in 1993. Numerous studies revealed a widespread distribution in various tissues and organs, which is reflected by its multiple physiological roles in health and disease. Because of its anti-inflammatory, anti-apoptotic and proliferative properties, ADM exhibits potent protective functions under diverse pathological conditions, but it is also critically involved in tumor progression. ADM has therefore raised great interest in therapeutic applications and several clinical trials already revealed promising results. However, because the receptor activation mode has not yet been fully elucidated, a rational design of potent and selective ligands is still challenging. Detailed information on the binding mode of ADM from a recently reported crystal structure as well as efforts to improve its plasma stability and bioavailability may help to overcome these limitations in the future. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.

  17. Potent reversible inhibition of myeloperoxidase by aromatic hydroxamates.

    Science.gov (United States)

    Forbes, Louisa V; Sjögren, Tove; Auchère, Françoise; Jenkins, David W; Thong, Bob; Laughton, David; Hemsley, Paul; Pairaudeau, Garry; Turner, Rufus; Eriksson, Håkan; Unitt, John F; Kettle, Anthony J

    2013-12-20

    The neutrophil enzyme myeloperoxidase (MPO) promotes oxidative stress in numerous inflammatory pathologies by producing hypohalous acids. Its inadvertent activity is a prime target for pharmacological control. Previously, salicylhydroxamic acid was reported to be a weak reversible inhibitor of MPO. We aimed to identify related hydroxamates that are good inhibitors of the enzyme. We report on three hydroxamates as the first potent reversible inhibitors of MPO. The chlorination activity of purified MPO was inhibited by 50% by a 5 nm concentration of a trifluoromethyl-substituted aromatic hydroxamate, HX1. The hydroxamates were specific for MPO in neutrophils and more potent toward MPO compared with a broad range of redox enzymes and alternative targets. Surface plasmon resonance measurements showed that the strength of binding of hydroxamates to MPO correlated with the degree of enzyme inhibition. The crystal structure of MPO-HX1 revealed that the inhibitor was bound within the active site cavity above the heme and blocked the substrate channel. HX1 was a mixed-type inhibitor of the halogenation activity of MPO with respect to both hydrogen peroxide and halide. Spectral analyses demonstrated that hydroxamates can act variably as substrates for MPO and convert the enzyme to a nitrosyl ferrous intermediate. This property was unrelated to their ability to inhibit MPO. We propose that aromatic hydroxamates bind tightly to the active site of MPO and prevent it from producing hypohalous acids. This mode of reversible inhibition has potential for blocking the activity of MPO and limiting oxidative stress during inflammation.

  18. Potent heterologous antifungal proteins from cheeseweed (Malva parviflora).

    Science.gov (United States)

    Wang, X; Bunkers, G J

    2000-12-20

    Two novel antifungal proteins were purified and characterized from cheeseweed (Malva parviflora). Both proteins, designated CW-1 and CW-2, are composed of two different subunits of 5000 and 3000 Da, respectively. These proteins possess very potent antifungal activities, and more interestingly the inhibition is fungicidal instead of fungistatic. At low salt condition, the IC(50) of CW-1 and CW-2 against Fusarium graminearum (Fg) is 2.5 ppm. At high salt condition which diminishes the antifungal activity of many antifungal proteins, both CW-1 and CW-2 still maintain potent activity against Fg with IC(50) of 10 ppm. The two subunits could be separated by gel filtration in the presence of 6 M urea, but their antifungal activity cannot be recovered after the removal of urea. Amino acid sequence analysis indicates that both subunits of CW-1 show homology to 2S albumin, whereas the two subunits of CW-2 have homology to vicilin protein from cotton. To our knowledge, this is the first report of isolation and characterization of heterologous antifungal proteins from any source.

  19. Discovery of Potent, Selective and Reversible Caspase-3 Inhibitors

    Institute of Scientific and Technical Information of China (English)

    Han Yongxin; John Tam; Paul Tawa; Donald W. Nicholson; Robert J. Zamboni; André Giroux; John Colucci; Christopher I. Bayly; Daniel J. Mckay; Sophie Roy; Steve Xanthoudakis; John Vaillancourt; Dita M. Rasper

    2004-01-01

    Recent studies towards understanding the molecular mechanisms of apoptosis have revealed the importance of a group of cysteinyl aspartate specific proteases, the caspases, in the programmed cell death process (Hengartner, M.O. Nature 2000, 407, 770). Caspase-3, in particular,has been characterized as the dominant effector caspase involved in the proteolytic cleavage of a variety of protein substrates including cytoskeletal proteins, kinases and DNA repair enzymes during apoptosis (Nicholson, D. W. Cell Death Differ. 1999, 6, 1028). The development of potent and selective caspase-3 inhibitors has thus emerged as an attractive therapeutic target. In the presentation,the identification of a series of potent, selective and reversible non-peptidyl caspase-3 inhibitors containing a pyrazinone core (1) will be presented. SAR optimization at R1, R2, R3 and R4 led to the discovery of inhibitors such as 2 with excellent in vitro activities (IC50 against rh-caspase-3: 5 nM; IC50 against camptothecin induced apoptotic cell death in NT2 cells: 20 nM). Compounds such as 2 also displayed excellent in vivo activities in a number of animal models of acute injuries (see: Methot, N. et al, J. Exp. Med. 2004, 119, 199; Toulmond, S. et al, British J. Pharm. 2004, 141,689; Holtzman,D.M. et al, JBC, 2002, 277, 30128), and selected examples will be discussed during the presentation.

  20. The brain and potent ART: the final frontier?

    Directory of Open Access Journals (Sweden)

    Powderly W

    2012-11-01

    Full Text Available The current era of potent antiretroviral therapy, with the resultant dramatic improval in survival of HIV-infected patients, has focussed much attention on non-infectious complications of HIV infection. It has been recognized since the early days of the epidemic that the brain is an important target of viral infection, with both direct and indirect effects leading to brain disease, especially the most severe form, progressive HIV-associated dementia. Potent antiretroviral therapy has clearly decreased the incidence and prevalence of dementia, and even with an ageing population there is little evidence of a significant return of severe HIV-associated neurological disease. There has been some recent attention to the concept of a milder form of HIV-associated neurocognitive disease (HAND, with some cohorts reporting prevalence rates of 30% or more, even in patients with otherwise well-controlled infection. However, diagnosis of HAND is methodologically difficult and debatable, with confounders such as mood, mental health, age and lack of standards in testing technique complicating the issue. Co-infection with hepatitis C is an additional complicating factor. It is important that we do not overdiagnosis or misclassify patients as having a potentially progressive complication of HIV infection. Equally, it is premature to alter therapeutic decision-making on this basis; in particular there are insufficient data to support a conclusion that specific antiviral agents are more likely to prevent or slow the progression of HAND.

  1. Chloroatranol, an extremely potent allergen hidden in perfumes

    DEFF Research Database (Denmark)

    Johansen, Jeanne Duus; Andersen, Klaus Ejner; Svedman, Cecilia

    2003-01-01

    Oak moss absolute is a long-known, popular natural extract widely used in perfumes. It is reported as the cause of allergic reactions in a significant number of those with perfume allergy. Oak moss absolute has been the target of recent research to identify its allergenic components. Recently...... an open test simulating the use of perfumes on the volar aspect of the forearms in a randomized and double-blinded design. A solution with 5 p.p.m. chloroatranol was used for 14 days, and, in case of no reaction, the applications were continued for another 14 days with a solution containing 25 p.p.m. All....... The dose eliciting a reaction in 50% of the test subjects at patch testing was 0.2 p.p.m. In conclusion, the hidden exposure to a potent allergen widely used in perfumes has caused a highly sensitized cohort of individuals. Judged from the elicitation profile, chloroatranol is the most potent allergen...

  2. Potent inhibition of HIV-1 replication by a Tat mutant.

    Science.gov (United States)

    Meredith, Luke W; Sivakumaran, Haran; Major, Lee; Suhrbier, Andreas; Harrich, David

    2009-11-10

    Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.

  3. Potent inhibition of HIV-1 replication by a Tat mutant.

    Directory of Open Access Journals (Sweden)

    Luke W Meredith

    Full Text Available Herein we describe a mutant of the two-exon HIV-1 Tat protein, termed Nullbasic, that potently inhibits multiple steps of the HIV-1 replication cycle. Nullbasic was created by replacing the entire arginine-rich basic domain of wild type Tat with glycine/alanine residues. Like similarly mutated one-exon Tat mutants, Nullbasic exhibited transdominant negative effects on Tat-dependent transactivation. However, unlike previously reported mutants, we discovered that Nullbasic also strongly suppressed the expression of unspliced and singly-spliced viral mRNA, an activity likely caused by redistribution and thus functional inhibition of HIV-1 Rev. Furthermore, HIV-1 virion particles produced by cells expressing Nullbasic had severely reduced infectivity, a defect attributable to a reduced ability of the virions to undergo reverse transcription. Combination of these inhibitory effects on transactivation, Rev-dependent mRNA transport and reverse transcription meant that permissive cells constitutively expressing Nullbasic were highly resistant to a spreading infection by HIV-1. Nullbasic and its activities thus provide potential insights into the development of potent antiviral therapeutics that target multiple stages of HIV-1 infection.

  4. Potent D-Peptide Inhibitors of HIV-1 Entry

    Energy Technology Data Exchange (ETDEWEB)

    Welch,B.; VanDemark, A.; Heroux, A.; Hill, C.; Kay, M.

    2007-01-01

    During HIV-1 entry, the highly conserved gp41 N-trimer pocket region becomes transiently exposed and vulnerable to inhibition. Using mirror-image phage display and structure-assisted design, we have discovered protease-resistant D-amino acid peptides (D-peptides) that bind the N-trimer pocket with high affinity and potently inhibit viral entry. We also report high-resolution crystal structures of two of these D-peptides in complex with a pocket mimic that suggest sources of their high potency. A trimeric version of one of these peptides is the most potent pocket-specific entry inhibitor yet reported by three orders of magnitude (IC50 = 250 pM). These results are the first demonstration that D-peptides can form specific and high-affinity interactions with natural protein targets and strengthen their promise as therapeutic agents. The D-peptides described here address limitations associated with current L-peptide entry inhibitors and are promising leads for the prevention and treatment of HIV/AIDS.

  5. Identification of a potent endothelium-derived angiogenic factor.

    Directory of Open Access Journals (Sweden)

    Vera Jankowski

    Full Text Available The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U from the secretome of human endothelial cells. The angiogenic effect of the endothelial secretome was partially reduced after incubation with alkaline phosphatase and abolished in the presence of suramin. In one fraction, purified to homogeneity by reversed phase and affinity chromatography, Up4U was identified by MALDI-LIFT-fragment-mass-spectrometry, enzymatic cleavage analysis and retention-time comparison. Beside a strong angiogenic effect on the yolk sac membrane and the developing rat embryo itself, Up4U increased the proliferation rate of endothelial cells and, in the presence of PDGF, of vascular smooth muscle cells. Up4U stimulated the migration rate of endothelial cells via P2Y2-receptors, increased the ability of endothelial cells to form capillary-like tubes and acts as a potent inducer of sprouting angiogenesis originating from gel-embedded EC spheroids. Endothelial cells released Up4U after stimulation with shear stress. Mean total plasma Up4U concentrations of healthy subjects (N=6 were sufficient to induce angiogenic and proliferative effects (1.34 ± 0.26 nmol L(-1. In conclusion, Up4U is a novel strong human endothelium-derived angiogenic factor.

  6. Epidemiological Studies of Potent Environmental Pathogen: Streptococcus pneumoniae

    Directory of Open Access Journals (Sweden)

    Nazir A. Brohi

    2016-12-01

    Full Text Available A general survey for six months was undertaken for the prevalence of environmental bacterium Streptococcus pneumoniae among the different age groups (3-65 years including both sexes from various hospitals of Hyderabad city. Laboratory examinations revealed S. pneumoniae as most potent environmental pathogen from the sputum and throat swabs of old aged patients and children respectively. During observations, 39 specimens were growth positive; the biochemistry of isolates revealed that they were coagulase, catalase and oxidase negative, TSI, gel hydrolysis positive and were able to ferment glucose, lactose, maltose, galactose, fructose, sucrose, starch and raffinose. The results of antimicrobial activity showed that pneumococci were resistant to the cefspan, septran, cravit, pipemetic acid, azomax, bacitracin, and penicillin and a clear zone of inhibition was observed on clithromycin, optochin, cefizox, genatamycin, minocyclin, levoflaxacin, and vancomycin. There were intermediate zone of inhibition found on claforan, nalidixic acid, amoxycillin, fosfomycin, fortum, and erythromycin on Mueller Hinton’s agar after 24 hours incubation

  7. Genomic discovery of potent chromatin insulators for human gene therapy.

    Science.gov (United States)

    Liu, Mingdong; Maurano, Matthew T; Wang, Hao; Qi, Heyuan; Song, Chao-Zhong; Navas, Patrick A; Emery, David W; Stamatoyannopoulos, John A; Stamatoyannopoulos, George

    2015-02-01

    Insertional mutagenesis and genotoxicity, which usually manifest as hematopoietic malignancy, represent major barriers to realizing the promise of gene therapy. Although insulator sequences that block transcriptional enhancers could mitigate or eliminate these risks, so far no human insulators with high functional potency have been identified. Here we describe a genomic approach for the identification of compact sequence elements that function as insulators. These elements are highly occupied by the insulator protein CTCF, are DNase I hypersensitive and represent only a small minority of the CTCF recognition sequences in the human genome. We show that the elements identified acted as potent enhancer blockers and substantially decreased the risk of tumor formation in a cancer-prone animal model. The elements are small, can be efficiently accommodated by viral vectors and have no detrimental effects on viral titers. The insulators we describe here are expected to increase the safety of gene therapy for genetic diseases.

  8. Deoxygedunin, a natural product with potent neurotrophic activity in mice.

    Directory of Open Access Journals (Sweden)

    Sung-Wuk Jang

    Full Text Available Gedunin, a family of natural products from the Indian neem tree, possess a variety of biological activities. Here we report the discovery of deoxygedunin, which activates the mouse TrkB receptor and its downstream signaling cascades. Deoxygedunin is orally available and activates TrkB in mouse brain in a BDNF-independent way. Strikingly, it prevents the degeneration of vestibular ganglion in BDNF -/- pups. Moreover, deoxygedunin robustly protects rat neurons from cell death in a TrkB-dependent manner. Further, administration of deoxygedunin into mice displays potent neuroprotective, anti-depressant and learning enhancement effects, all of which are mediated by the TrkB receptor. Hence, deoxygedunin imitates BDNF's biological activities through activating TrkB, providing a powerful therapeutic tool for treatment of various neurological diseases.

  9. New Conjugates of Quinoxaline as Potent Antitubercular and Antibacterial Agents

    Directory of Open Access Journals (Sweden)

    Ramalingam Peraman

    2016-01-01

    Full Text Available Considering quinoxaline as a privileged structure for the design of potent intercalating agents, some new sugar conjugates of quinoxaline were synthesized and characterized by IR, 1HNMR, 13C NMR, and mass spectral data. In vitro testing for antitubercular and antimicrobial activities was performed against Mycobacterium tuberculosis H37Rv and some pathogenic bacteria. Results revealed that conjugate containing ribose moiety demonstrated the most promising activity against Mycobacteria and bacteria with minimum inhibitory concentrations (MIC of 0.65 and 2.07 μM, respectively. Other conjugates from xylose, glucose, and mannose were moderately active whilst disaccharides conjugates were found to be less active. In silico docking analysis of prototype compound revealed that ATP site of DNA gyrase B subunit could be a possible site for inhibitory action of these synthesized compounds.

  10. New Conjugates of Quinoxaline as Potent Antitubercular and Antibacterial Agents.

    Science.gov (United States)

    Peraman, Ramalingam; Kuppusamy, Rajendran; Killi, Sunil Kumar; Reddy, Y Padmanabha

    2016-01-01

    Considering quinoxaline as a privileged structure for the design of potent intercalating agents, some new sugar conjugates of quinoxaline were synthesized and characterized by IR, (1)HNMR, (13)C NMR, and mass spectral data. In vitro testing for antitubercular and antimicrobial activities was performed against Mycobacterium tuberculosis H 37 Rv and some pathogenic bacteria. Results revealed that conjugate containing ribose moiety demonstrated the most promising activity against Mycobacteria and bacteria with minimum inhibitory concentrations (MIC) of 0.65 and 2.07 μM, respectively. Other conjugates from xylose, glucose, and mannose were moderately active whilst disaccharides conjugates were found to be less active. In silico docking analysis of prototype compound revealed that ATP site of DNA gyrase B subunit could be a possible site for inhibitory action of these synthesized compounds.

  11. Cocaethylene is more potent than cocaine in mediating lethality.

    Science.gov (United States)

    Hearn, W L; Rose, S; Wagner, J; Ciarleglio, A; Mash, D C

    1991-06-01

    Cocaethylene is a pharmacologically active cocaine metabolite that is formed in the presence of ethanol by the activity of liver enzymes. The pharmacology of cocaethylene has not been extensively investigated and its acute toxicity is unknown. The acute toxicity of cocaethylene was compared to cocaine in Swiss-Webster mice. The LD50 of cocaethylene was 60.7 mg/kg and 63.8 mg/kg in female and male mice, respectively. In comparison, the LD50 of cocaine was 93.0 mg/kg in both female and male mice. These studies demonstrate that the cocaine-alcohol metabolite, cocathylene, is more potent in mediating lethality than the parent drug.

  12. Potent Antiplasmodial Alkaloids and Flavonoids from Dasymaschalon acuminatum

    Directory of Open Access Journals (Sweden)

    Ratchanaporn Chokchaisiri

    2015-01-01

    Full Text Available A new aporphine alkaloid, 7-epi-duguetine (1 together with one known alkaloid, dicentrinone (2, and four known flavonoids, quercetin 3,7-dimethyl ether 3′ -O- α -L-rhamnopyranosyl-(1 g 2-β-D-glucopyranoside (3, galangin 5-methyl ether (4, 5,7-dimethoxy-3-hydroxyflavone (5, and 3,5,7-trimethoxyflavone (6, were isolated from the leaves of Dasymaschalon acuminatum , a new plant species which has not been investigated phytochemically before. The structures of the isolated compounds were elucidated through extensive NMR spectroscopic analysis. All isolates were evaluated for antiplasmodial activity against Plasmodium falciparum strain K1 and 7- epi -duguetine was found to exhibit potent activity with an IC 50 of 0.385 m g/ml .

  13. Discovery of Phenylglycine Lactams as Potent Neutral Factor VIIa Inhibitors.

    Science.gov (United States)

    Wurtz, Nicholas R; Parkhurst, Brandon L; Jiang, Wen; DeLucca, Indawati; Zhang, Xiaojun; Ladziata, Vladimir; Cheney, Daniel L; Bozarth, Jeffrey R; Rendina, Alan R; Wei, Anzhi; Luettgen, Joseph M; Wu, Yiming; Wong, Pancras C; Seiffert, Dietmar A; Wexler, Ruth R; Priestley, E Scott

    2016-12-08

    Inhibitors of Factor VIIa (FVIIa), a serine protease in the clotting cascade, have shown strong antithrombotic efficacy in preclinical thrombosis models with minimal bleeding liabilities. Discovery of potent, orally active FVIIa inhibitors has been largely unsuccessful because known chemotypes have required a highly basic group in the S1 binding pocket for high affinity. A recently reported fragment screening effort resulted in the discovery of a neutral heterocycle, 7-chloro-3,4-dihydroisoquinolin-1(2H)-one, that binds in the S1 pocket of FVIIa and can be incorporated into a phenylglycine FVIIa inhibitor. Optimization of this P1 binding group led to the first series of neutral, permeable FVIIa inhibitors with low nanomolar potency.

  14. Urea-containing peptide boronic acids as potent proteasome inhibitors.

    Science.gov (United States)

    Han, Li-Qiang; Yuan, Xia; Wu, Xing-Yu; Li, Ri-Dong; Xu, Bo; Cheng, Qing; Liu, Zhen-Ming; Zhou, Tian-Yan; An, Hao-Yun; Wang, Xin; Cheng, Tie-Ming; Ge, Ze-Mei; Cui, Jing-Rong; Li, Run-Tao

    2017-01-05

    A novel class of urea-containing peptide boronic acids as proteasome inhibitors was designed by introducing a urea scaffold to replace an amido bond. Compounds were synthesized and their antitumor activities were evaluated. After two rounds of optimizations, the compound I-14 was found to be a potent proteasome inhibitor. Compared with Bortezomib, I-14 showed higher potency against the chymotrypsin-like activity of human 20S proteasome (IC50 < 1 pM), similar potency against four different cancer cell lines (IC50 < 10 nM), and better pharmacokinetic profile. Furthermore, I-14 significantly inhibited tumor growth in Bel7404 mouse xenograft model. The excellent proteasome inhibition by I-14 was rationalized through docking and molecular dynamics studies. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  15. Anti-topoisomerase drugs as potent inducers of chromosomal aberrations

    Directory of Open Access Journals (Sweden)

    Loredana Bassi

    2000-12-01

    Full Text Available DNA topoisomerases catalyze topological changes in DNA that are essential for normal cell cycle progression and therefore they are a preferential target for the development of anticancer drugs. Anti-topoisomerase drugs can be divided into two main classes: "cleavable complex" poisons and catalytic inhibitors. The "cleavable complex" poisons are very effective as anticancer drugs but are also potent inducers of chromosome aberrations so they can cause secondary malignancies. Catalytic inhibitors are cytotoxic but they do not induce chromosome aberrations. Knowledge about the mechanism of action of topoisomerase inhibitors is important to determine the best anti-topoisomerase combinations, with a reduced risk of induction of secondary malignancies.As topoisomerases de DNA catalisam alterações topológicas no DNA que são essenciais para a progressão do ciclo celular normal e, portanto, são um alvo preferencial para o desenvolvimento de drogas anticâncer. Drogas anti-topoisomerases podem ser divididas em duas classes principais: drogas anti-"complexos cliváveis" e inibidores catalíticos. As drogas anti-"complexos cliváveis" são muito eficazes como drogas anticancerígenas, mas são também potentes indutores de aberrações cromossômicas, podendo causar neoplasias malignas secundárias. Inibidores catalíticos são citotóxicos mas não induzem aberrações cromossômicas. Conhecimento a respeito do mecanismo de ação de inibidores de topoisomerases é importante para determinar as melhores combinações anti-topoisomerases, com um reduzido risco de indução de neoplasias malignas secundárias.

  16. Discovery of potent imidazole and cyanophenyl containing farnesyltransferase inhibitors with improved oral bioavailability.

    Science.gov (United States)

    Tong, Yunsong; Lin, Nan-Horng; Wang, Le; Hasvold, Lisa; Wang, Weibo; Leonard, Nicholas; Li, Tongmei; Li, Qun; Cohen, Jerry; Gu, Wen-Zhen; Zhang, Haiying; Stoll, Vincent; Bauch, Joy; Marsh, Kennan; Rosenberg, Saul H; Sham, Hing L

    2003-05-05

    A pyridyl moiety was introduced into a previously developed series of farnesyltransferase inhibitors containing imidazole and cyanophenyl (such as 4), resulting in potent inhibitors with improved pharmacokinetics.

  17. Synthetic galactomannans with potent anti-HIV activity.

    Science.gov (United States)

    Budragchaa, Davaanyam; Bai, Shiming; Kanamoto, Taisei; Nakashima, Hideki; Han, Shuqin; Yoshida, Takashi

    2015-10-05

    Ring-opening polymerization of a new 1,6-anhydro disaccharide monomer, 1, 6-anhydro-2, 3-di-O-benzyl-4-O-(2', 3', 4', 6'-tetra-O-benzyl-α-d-galactopyranosyl)-α-d-mannopyranose, was carried out using PF5 as a catalyst under high vacuum at -60°C to give galactose branched mannopyranan (synthetic galactomannan), 4-O-α-d-galactopyranosyl-(1→6)-α-d-mannopyranan, after debenzylation with Na in liquid NH3. The ring-opening copolymerization with 1, 6-anhydro-tri-O-benzyl-α-d-mannopyranose in various feeds was also performed to give synthetic galactomannans with various proportions of galactose branches. After sulfation, sulfated synthetic galactomannans were found to have anti-HIV activity and cytotoxicity as high and low as those of standard curdlan and dextran sulfates, respectively, which are potent anti-HIV sulfated polysaccharides with low cytotoxicity. The anti-HIV mechanism of sulfated synthetic galactomannans used by poly-l-lysine as a model peptide of the HIV surface protein was estimated by using SPR, DSL, and zeta potential measurements, revealing the electrostatic interaction between negatively charged sulfate groups and positively charged amino groups.

  18. Carvacrol as a potent natural acaricide against Dermanyssus gallinae.

    Science.gov (United States)

    Tabari, Mohaddeseh Abouhosseini; Youssefi, Mohammad Reza; Barimani, Alireza; Araghi, Atefeh

    2015-10-01

    Resistance to conventional synthetic pesticides has been widely reported in Dermanyssus gallinae in poultry production systems. Introducing novel acaricides to poultry industry today is more urgent than ever. Research in this field recently focused on plants and plant-derived compounds as acaricides. In the present study, acaricidal activity of three plant bioactive components, carvacrol, thymol, and farnesol, was assessed against D. gallinae and compared with synthetic pesticide permethrin. Mode of acaricidal action was determined by contact toxicity and fumigant toxicity bioassays. Except farnesol which did not cause any mortality, carvacrol and thymol were found to be toxic to D. gallinae with LD50 values of 1 and 3.15 μg/cm(3), respectively. Permethrin gave the LD50 value of 31.95 μg/cm(3) which was less efficient than carvacrol and thymol. In fumigant toxicity bioassay, mortality rate in carvacrol- and thymol-treated groups in closed method was significantly higher than the open one. On the other hand, permethrin exhibited poor fumigant toxicity as there was no statistically significant difference between mortality rate in open and closed methods. These findings revealed that mechanism of acaricidal activity of carvacrol and thymol but not permethrin was mainly due to fumigant action. Results of the present study suggested that carvacrol and thymol, especially carvacrol, can be developed as a novel potent bioacaricide against D. gallinae.

  19. Highly potent silver-organoalkoxysilane antimicrobial porous nanomembrane

    Science.gov (United States)

    Umar, Sirajo; Liu, Yuanfeng; Wu, Yiguang; Li, Guangtao; Ding, Jiabo; Xiong, Runsong; Chen, Jinchun

    2013-04-01

    We used a simple electrospinning technique to fabricate a highly potent silver-organoalkoxysilane antimicrobial composite from AgNO3-polyvinylpyrrolidone (PVP)/3-aminopropyltrimethoxysilane (APTMS)/tetraethoxysilane (TEOS) solution. Spectroscopic and microscopic analyses of the composite showed that the fibers contain an organoalkoxysilane `skeleton,' 0.18 molecules/nm2 surface amino groups, and highly dispersed and uniformly distributed silver nanoparticles (5 nm in size). Incorporation of organoalkoxysilanes is highly beneficial to the antimicrobial mat as (1) amino groups of APTMS are adhesive and biocidal to microorganisms, (2) polycondensation of APTMS and TEOS increases the membrane's surface area by forming silicon bonds that stabilize fibers and form a composite mat with membranous structure and high porosity, and (3) the organoalkoxysilanes are also instrumental to the synthesis of the very small-sized and highly dispersed silver metal particles in the fiber mat. Antimicrobial property of the composite was evaluated by disk diffusion, minimum inhibition concentration (MIC), kinetic, and extended use assays on bacteria (Escherichia coli, Bacillus anthracis, Staphylococcus aureus, and Brucella suis), a fungus (Aspergillus niger), and the Newcastle disease virus. The membrane shows quick and sustained broad-spectrum antimicrobial activity. Only 0.3 mg of fibers is required to achieve MIC against all the test organisms. Bacteria are inhibited within 30 min of contact, and the fibers can be used repeatedly. The composite is silver efficient and environment friendly, and its membranous structure is suitable for many practical applications as in air filters, antimicrobial linen, coatings, bioadhesives, and biofilms.

  20. Desmodium gangeticum: a potent anti-ulcer agent.

    Science.gov (United States)

    Dharmani, Poonam; Mishra, Pushpesh Kumar; Maurya, Rakesh; Chauhan, Vinay Singh; Palit, Gautam

    2005-06-01

    The present study was designed to investigate anti-ulcerogenic property of ethanolic extract of Desmodium gangeticum (DG) against cold restraint (CRU, 2 hr cold restraint stress), aspirin (ASP, 150 mg/kg orally), alcohol (AL, absolute alcohol 1 ml/200gm) and pyloric ligation (PL, 4 hr pylorus ligation) induced gastric ulcer models in Sprague Dawley rats, and histamine (HST, 0.25 mg/kg) induced duodenal ulcer in guinea pigs. We found that DG at a dose of 200mg/kg, (orally), markedly decreased the incidence of ulcers in all the above models. DG showed significant protection against CRU (68.37%), AL (88.87%), ASP (38.2%), PL (40.63%) and HST (63.15%) induced ulcer models, whereas standard drug omeprazole (OMZ) showed protection index of 83.86, 56.35, 70.31 and 84.21%, respectively in CRU, ASP, PL and HST models. Sucralfate as standard drug showed 92.64% protection in AL model. DG significantly reduced acid secretion 41.61%, whereas OMZ produced 43.13% reduction. Treatment with DG showed increase in mucin secretion by 56.17%, whereas OMZ showed 12.45% increase. Anti-ulcer effect of DG may be due to its cytoprotective effect along with antisecretory activity and could act as a potent therapeutic agent against peptic ulcer disease.

  1. 2-acetylphenol analogs as potent reversible monoamine oxidase inhibitors

    Directory of Open Access Journals (Sweden)

    Legoabe LJ

    2015-07-01

    Full Text Available Lesetja J Legoabe,1 Anél Petzer,1 Jacobus P Petzer1,21Centre of Excellence for Pharmaceutical Sciences, 2Department of Pharmaceutical Chemistry, School of Pharmacy, North-West University, Potchefstroom, South AfricaAbstract: Based on a previous report that substituted 2-acetylphenols may be promising leads for the design of novel monoamine oxidase (MAO inhibitors, a series of C5-substituted 2-acetylphenol analogs (15 and related compounds (two were synthesized and evaluated as inhibitors of human MAO-A and MAO-B. Generally, the study compounds exhibited inhibitory activities against both MAO-A and MAO-B, with selectivity for the B isoform. Among the compounds evaluated, seven compounds exhibited IC50 values <0.01 µM for MAO-B inhibition, with the most selective compound being 17,000-fold selective for MAO-B over the MAO-A isoform. Analyses of the structure–activity relationships for MAO inhibition show that substitution on the C5 position of the 2-acetylphenol moiety is a requirement for MAO-B inhibition, and the benzyloxy substituent is particularly favorable in this regard. This study concludes that C5-substituted 2-acetylphenol analogs are potent and selective MAO-B inhibitors, appropriate for the design of therapies for neurodegenerative disorders such as Parkinson’s disease.Keywords: monoamine oxidase, MAO, inhibition, 2-acetylphenol, structure–activity relationship

  2. Acylthiourea, acylurea, and acylguanidine derivatives with potent hedgehog inhibiting activity.

    Science.gov (United States)

    Solinas, Antonio; Faure, Hélène; Roudaut, Hermine; Traiffort, Elisabeth; Schoenfelder, Angèle; Mann, André; Manetti, Fabrizio; Taddei, Maurizio; Ruat, Martial

    2012-02-23

    The Smoothened (Smo) receptor is the major transducer of the Hedgehog (Hh) signaling pathway. On the basis of the structure of the acylthiourea Smo antagonist (MRT-10), a number of different series of analogous compounds were prepared by ligand-based structural optimization. The acylthioureas, originally identified as actives, were converted into the corresponding acylureas or acylguanidines. In each series, similar structural trends delivered potent compounds with IC(50) values in the nanomolar range with respect to the inhibition of the Hh signaling pathway in various cell-based assays and of BODIPY-cyclopamine binding to human Smo. The similarity of their biological activities, in spite of discrete structural differences, may reveal the existence of hydrogen-bonding interactions between the ligands and the receptor pocket. Biological potency of compounds 61, 72, and 86 (MRT-83) were comparable to those of the clinical candidate GDC-0449. These findings suggest that these original molecules will help delineate Smo and Hh functions and can be developed as potential anticancer agents.

  3. HU-444, a Novel, Potent Anti-Inflammatory, Nonpsychotropic Cannabinoid.

    Science.gov (United States)

    Haj, Christeene G; Sumariwalla, Percy F; Hanuš, Lumír; Kogan, Natalya M; Yektin, Zhana; Mechoulam, Raphael; Feldmann, Mark; Gallily, Ruth

    2015-10-01

    Cannabidiol (CBD) is a component of cannabis, which does not cause the typical marijuana-type effects, but has a high potential for use in several therapeutic areas. In contrast to Δ(9)-tetrahydrocannabinol (Δ(9)-THC), it binds very weakly to the CB1 and CB2 cannabinoid receptors. It has potent activity in both in vitro and in vivo anti-inflammatory assays. Thus, it lowers the formation of tumor necrosis factor (TNF)-α, a proinflammatory cytokine, and was found to be an oral antiarthritic therapeutic in murine collagen-induced arthritis in vivo. However, in acidic media, it can cyclize to the psychoactive Δ(9)-THC. We report the synthesis of a novel CBD derivative, HU-444, which cannot be converted by acid cyclization into a Δ(9)-THC-like compound. In vitro HU-444 had anti-inflammatory activity (decrease of reactive oxygen intermediates and inhibition of TNF-α production by macrophages); in vivo it led to suppression of production of TNF-α and amelioration of liver damage as well as lowering of mouse collagen-induced arthritis. HU-444 did not cause Δ(9)-THC-like effects in mice. We believe that HU-444 represents a potential novel drug for rheumatoid arthritis and other inflammatory diseases.

  4. Potent Inhibition of Acid Ceramidase by Novel B-13 Analogues

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    Denny Proksch

    2011-01-01

    Full Text Available The lipid-signalling molecule ceramide is known to induce apoptosis in a variety of cell types. Inhibition of the lysosomal acid ceramidase can increase cellular ceramide levels and thus induce apoptosis. Indeed, inhibitors of acid ceramidase have been reported to induce cell death and to display potentiating effects to classical radio- or chemo therapy in a number of in vitro and in vivo cancer models. The most potent in vitro inhibitor of acid ceramidase, B-13, recently revealed to be virtually inactive towards lysosomal acid ceramidase in living cells. In contrast, a number of weakly basic B-13 analogues have been shown to accumulate in the acidic compartments of living cells and to efficiently inhibit lysosomal acid ceramidase. However, introduction of weakly basic groups at the ω-position of the fatty acid moiety of B-13 led to a significant reduction of potency towards acid ceramidase from cellular extracts. Herein, we report a novel B-13-derived scaffold for more effective inhibitors of acid ceramidase. Furthermore, we provide hints for an introduction of basic functional groups at an alternative site of the B-13 scaffold that do not interfere with acid ceramidase inhibition in vitro.

  5. Bioisosteric phentolamine analogs as potent alpha-adrenergic antagonists.

    Science.gov (United States)

    Hong, Seoung-Soo; Bavadekar, Supriya A; Lee, Sang-Il; Patil, Popat N; Lalchandani, S G; Feller, Dennis R; Miller, Duane D

    2005-11-01

    The synthesis and biological evaluation of a new series of bioisosteric phentolamine analogs are described. Replacement of the carbon next to the imidazoline ring of phentolamine with a nitrogen atom provides compounds (2, 3) that are about 1.6 times and 4.1 times more potent functionally than phentolamine on rat alpha1-adrenergic receptors, respectively. In receptor binding assays, the affinities of phentolamine and its bioisosteric analogs were determined on the human embryonic kidney (HEK) and Chinese Hamster ovary (CHO) cell lines expressing the human alpha1- and alpha2-AR subtypes, respectively. Analogs 2 and 3, both, displayed higher binding affinities at the alpha2- versus the alpha1-ARs, affinities being the least at the alpha1B-AR. Binding affinities of the methoxy ether analog 2 were greater than those of the phenolic analog 3 at all six alpha-AR subtypes. One of the nitrogen atoms in the imidazoline ring of phentolamine was replaced with an oxygen atom to give compounds 4 and 5, resulting in a 2-substituted oxazoline ring. The low functional antagonist activity on rat aorta, and binding potencies of these two compounds on human alpha1A- and alpha2A-AR subtypes indicate that a basic functional group is important for optimum binding to the alpha1- and alpha2A-adrenergic receptors.

  6. Iota-Carrageenan is a potent inhibitor of rhinovirus infection

    Directory of Open Access Journals (Sweden)

    Meier Christiane

    2008-09-01

    Full Text Available Abstract Background Human rhinoviruses (HRVs are the predominant cause of common cold. In addition, HRVs are implicated in the worsening of COPD and asthma, as well as the loss of lung transplants. Despite significant efforts, no anti-viral agent is approved for the prevention or treatment of HRV-infection. Results In this study we demonstrate that Iota-Carrageenan, a sulphated polysaccharide derived from red seaweed, is a potent anti-rhinoviral substance in-vitro. Iota-Carrageenan reduces HRV growth and inhibits the virus induced cythopathic effect of infected HeLa cells. In addition, Iota-Carrageenan effectively prevents the replication of HRV1A, HRV2, HRV8, HRV14, HRV16, HRV83 and HRV84 in primary human nasal epithelial cells in culture. The data suggest that Iota-Carrageenan acts primarily by preventing the binding or the entry of virions into the cells. Conclusion Since HRV infections predominately occur in the nasal cavity and the upper respiratory tract, a targeted treatment with a product containing Iota-Carrageenan is conceivable. Clinical trials are needed to determine whether Iota-Carrageenan-based products are effective in the treatment or prophylaxis of HRV infections.

  7. Small Molecule Anticonvulsant Agents with Potent In Vitro Neuroprotection

    Science.gov (United States)

    Smith, Garry R.; Zhang, Yan; Du, Yanming; Kondaveeti, Sandeep K.; Zdilla, Michael J.; Reitz, Allen B.

    2012-01-01

    Severe seizure activity is associated with recurring cycles of excitotoxicity and oxidative stress that result in progressive neuronal damage and death. Intervention to halt these pathological processes is a compelling disease-modifying strategy for the treatment of seizure disorders. In the present study, a core small molecule with anticonvulsant activity has been structurally optimized for neuroprotection. Phenotypic screening of rat hippocampal cultures with nutrient medium depleted of antioxidants was utilized as a disease model. Increased cell death and decreased neuronal viability produced by acute treatment with glutamate or hydrogen peroxide were prevented by our novel molecules. The neuroprotection associated with this chemical series has marked structure activity relationships that focus on modification of the benzylic position of a 2-phenyl-2-hydroxyethyl sulfamide core structure. Complete separation between anticonvulsant activity and neuroprotective action was dependent on substitution at the benzylic carbon. Chiral selectivity was evident in that the S-enantiomer of the benzylic hydroxy group had neither neuroprotective nor anticonvulsant activity, while the R-enantiomer of the lead compound had full neuroprotective action at ≤40 nM and antiseizure activity in three animal models. These studies indicate that potent, multifunctional neuroprotective anticonvulsants are feasible within a single molecular entity. PMID:22535312

  8. Plants from Brazilian Cerrado with potent tyrosinase inhibitory activity.

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    Paula Monteiro Souza

    Full Text Available The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05 tyrosinase inhibitory activity exhibiting the IC₅₀ value of 11.88 µg/mL, compared to kojic acid (IC₅₀ value of 13.14 µg/mL. Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC₅₀ value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations.

  9. Hemin as a generic and potent protein misfolding inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yanqin [School of Chemistry and Physics, The University of Adelaide, Adelaide, SA 5005 (Australia); Carver, John A. [Discipline of Pharmacology, The University of Adelaide, Adelaide, SA 5005 (Australia); Ho, Lam H.; Elias, Abigail K. [School of Chemistry and Physics, The University of Adelaide, Adelaide, SA 5005 (Australia); Musgrave, Ian F. [Research School of Chemistry, The Australian National University, Canberra, ACT 0200 (Australia); Pukala, Tara L., E-mail: tara.pukala@adelaide.edu.au [School of Chemistry and Physics, The University of Adelaide, Adelaide, SA 5005 (Australia)

    2014-11-14

    Highlights: • Hemin prevents Aβ42, α-synuclein and RCM-κ-casein forming amyloid fibrils. • Hemin inhibits the β-sheet structure formation of Aβ42. • Hemin reduces the cell toxicity caused by fibrillar Aβ42. • Hemin dissociates partially formed Aβ42 fibrils. • Hemin prevents amorphous aggregation by ADH, catalase and γs-crystallin. - Abstract: Protein misfolding causes serious biological malfunction, resulting in diseases including Alzheimer’s disease, Parkinson’s disease and cataract. Molecules which inhibit protein misfolding are a promising avenue to explore as therapeutics for the treatment of these diseases. In the present study, thioflavin T fluorescence and transmission electron microscopy experiments demonstrated that hemin prevents amyloid fibril formation of kappa-casein, amyloid beta peptide and α-synuclein by blocking β-sheet structure assembly which is essential in fibril aggregation. Further, inhibition of fibril formation by hemin significantly reduces the cytotoxicity caused by fibrillar amyloid beta peptide in vitro. Interestingly, hemin degrades partially formed amyloid fibrils and prevents further aggregation to mature fibrils. Light scattering assay results revealed that hemin also prevents protein amorphous aggregation of alcohol dehydrogenase, catalase and γs-crystallin. In summary, hemin is a potent agent which generically stabilises proteins against aggregation, and has potential as a key molecule for the development of therapeutics for protein misfolding diseases.

  10. Scaffold hopping via ANCHOR.QUERY : beta-lactams as potent p53-MDM2 antagonists

    NARCIS (Netherlands)

    Shaabani, S.; Neochoritis, C. G.; Twarda-Clapa, Aleksandra; Musielak, Bogdan; Holak, Tad A.; Domling, A.

    2017-01-01

    Using the pharmacophore-based virtual screening platform ANCHOR.QUERY, we morphed our recently described Ugi-4CR scaffold towards a beta-lactam scaffold with potent p53-MDM2 antagonizing activities. 2D-HSQC and FP measurements confirm potent MDM2 binding. Molecular modeling studies were used to unde

  11. Bicyclams, selective antagonists of the human chemokine receptor CXCR4, potently inhibit feline immunodeficiency virus replication

    NARCIS (Netherlands)

    Horzinek, M.C.; Egberink, H.F.; Clercq, E. de; Vliet, A.L.W. van; Balzarini, J.; Bridger, G.J.; Henson, G.; Schols, D.

    1999-01-01

    Bicyclams are low-molecular-weight anti-human immunodeficiency virus (HIV) agents that have been shown to act as potent and selective CXC chemokine receptor 4 (CXCR4) antagonists. Here, we demonstrate that bicyclams are potent inhibitors of feline immunodeficiency virus (FIV) replication when evalua

  12. Hydroxychavicol: a potent xanthine oxidase inhibitor obtained from the leaves of betel, Piper betle.

    Science.gov (United States)

    Murata, Kazuya; Nakao, Kikuyo; Hirata, Noriko; Namba, Kensuke; Nomi, Takao; Kitamura, Yoshihisa; Moriyama, Kenzo; Shintani, Takahiro; Iinuma, Munekazu; Matsuda, Hideaki

    2009-07-01

    The screening of Piperaceous plants for xanthine oxidase inhibitory activity revealed that the extract of the leaves of Piper betle possesses potent activity. Activity-guided purification led us to obtain hydroxychavicol as an active principle. Hydroxychavicol is a more potent xanthine oxidase inhibitor than allopurinol, which is clinically used for the treatment of hyperuricemia.

  13. Synthesis of potent, substituted carbazoles as selective androgen receptor modulators (SARMs).

    Science.gov (United States)

    Miller, Chris P; Bhaket, Pushpal; Muthukaman, Nagarajan; Lyttle, C Richard; Shomali, Maysoun; Gallacher, Kyla; Slocum, Connie; Hattersley, Gary

    2010-12-15

    The synthesis and in vitro binding affinity for a novel series of potent androgen receptor modulators is described. One of the more potent compounds (17, RAD35010) was further characterized in vivo where it restored levator ani weight in castrated male rats to near sham level while having no significant effect on prostate weight.

  14. A potent potassium channel blocker from Mesobuthus eupeus scorpion venom.

    Science.gov (United States)

    Gao, Bin; Peigneur, Steve; Tytgat, Jan; Zhu, Shunyi

    2010-12-01

    Scorpion venom-derived peptidyl toxins are valuable pharmacological tools for investigating the structure-function relationship of ion channels. Here, we report the purification, sequencing and functional characterization of a new K(+) channel blocker (MeuKTX) from the venom of the scorpion Mesobuthus eupeus. Effects of MeuKTX on ten cloned potassium channels in Xenopus oocytes were evaluated using two-electrode voltage-clamp recordings. MeuKTX is the orthologue of BmKTX (α-KTx3.6), a known Kv1.3 blocker from the scorpion Mesobuthus martensii, and classified as α-KTx3.13. MeuKTX potently blocks rKv1.1, rKv1.2 and hKv1.3 channels with 50% inhibitory concentration (IC(50)) of 203.15 ± 4.06 pM, 8.92 ± 2.3 nM and 171 ± 8.56 pM, respectively, but does not affect rKv1.4, rKv1.5, hKv3.1, rKv4.3, and hERG channels even at 2 μM concentration. At this high concentration, MeuKTX is also active on rKv1.6 and Shaker IR. Our results also demonstrate that MeuKTX and BmKTX have the same channel spectrum and similar pharmacological potency. Analysis of the structure-function relationships of α-KTx3 subfamily toxins allows us to recognize several key sites which may be useful for designing toxins with improved activity on hKv1.3, an attractive target for T-cell mediated autoimmune diseases.

  15. Discovery of potent broad spectrum antivirals derived from marine actinobacteria.

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    Avi Raveh

    Full Text Available Natural products provide a vast array of chemical structures to explore in the discovery of new medicines. Although secondary metabolites produced by microbes have been developed to treat a variety of diseases, including bacterial and fungal infections, to date there has been limited investigation of natural products with antiviral activity. In this report, we used a phenotypic cell-based replicon assay coupled with an iterative biochemical fractionation process to identify, purify, and characterize antiviral compounds produced by marine microbes. We isolated a compound from Streptomyces kaviengensis, a novel actinomycetes isolated from marine sediments obtained off the coast of New Ireland, Papua New Guinea, which we identified as antimycin A1a. This compound displays potent activity against western equine encephalitis virus in cultured cells with half-maximal inhibitory concentrations of less than 4 nM and a selectivity index of greater than 550. Our efforts also revealed that several antimycin A analogues display antiviral activity, and mechanism of action studies confirmed that these Streptomyces-derived secondary metabolites function by inhibiting the cellular mitochondrial electron transport chain, thereby suppressing de novo pyrimidine synthesis. Furthermore, we found that antimycin A functions as a broad spectrum agent with activity against a wide range of RNA viruses in cultured cells, including members of the Togaviridae, Flaviviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Finally, we demonstrate that antimycin A reduces central nervous system viral titers, improves clinical disease severity, and enhances survival in mice given a lethal challenge with western equine encephalitis virus. Our results provide conclusive validation for using natural product resources derived from marine microbes as source material for antiviral drug discovery, and they indicate that host mitochondrial electron transport is a viable

  16. Discovery of potent broad spectrum antivirals derived from marine actinobacteria.

    Science.gov (United States)

    Raveh, Avi; Delekta, Phillip C; Dobry, Craig J; Peng, Weiping; Schultz, Pamela J; Blakely, Pennelope K; Tai, Andrew W; Matainaho, Teatulohi; Irani, David N; Sherman, David H; Miller, David J

    2013-01-01

    Natural products provide a vast array of chemical structures to explore in the discovery of new medicines. Although secondary metabolites produced by microbes have been developed to treat a variety of diseases, including bacterial and fungal infections, to date there has been limited investigation of natural products with antiviral activity. In this report, we used a phenotypic cell-based replicon assay coupled with an iterative biochemical fractionation process to identify, purify, and characterize antiviral compounds produced by marine microbes. We isolated a compound from Streptomyces kaviengensis, a novel actinomycetes isolated from marine sediments obtained off the coast of New Ireland, Papua New Guinea, which we identified as antimycin A1a. This compound displays potent activity against western equine encephalitis virus in cultured cells with half-maximal inhibitory concentrations of less than 4 nM and a selectivity index of greater than 550. Our efforts also revealed that several antimycin A analogues display antiviral activity, and mechanism of action studies confirmed that these Streptomyces-derived secondary metabolites function by inhibiting the cellular mitochondrial electron transport chain, thereby suppressing de novo pyrimidine synthesis. Furthermore, we found that antimycin A functions as a broad spectrum agent with activity against a wide range of RNA viruses in cultured cells, including members of the Togaviridae, Flaviviridae, Bunyaviridae, Picornaviridae, and Paramyxoviridae families. Finally, we demonstrate that antimycin A reduces central nervous system viral titers, improves clinical disease severity, and enhances survival in mice given a lethal challenge with western equine encephalitis virus. Our results provide conclusive validation for using natural product resources derived from marine microbes as source material for antiviral drug discovery, and they indicate that host mitochondrial electron transport is a viable target for the

  17. The analgesic activity of Bestatin as a potent APN inhibitor

    Directory of Open Access Journals (Sweden)

    Mei-Rong Jia

    2010-06-01

    Full Text Available Bestatin, a small molecular weight dipeptide, is a potent inhibitor of various aminopeptidases as well as LTA4 hydrolase. Various physiological functions of Bestatin have been identified, viz.: (1 an immunomodifier for enhancing the proliferation of normal human bone marrow granulocyte–macrophage progenitor cells to form CFU-GM colonies; Bestatin exerts a direct stimulating effect on lymphocytes via its fixation on the cell surface and an indirect effect on monocytes via aminopeptidase B inhibition of tuftsin catabolism; (2 an immunorestorator and curative or preventive agent for spontaneous tumor; Bestatin alone or its combination with chemicals can prolongate the disease-free interval and survival period in adult acute or chronic leukemia, therefore, it was primarily marketed in 1987 in Japan as an anticancer drug and servers as the only marketed inhibitor of Aminopeptidase N (APN/CD13 to cure leukemia to date; (3 a pan-hematopoietic stimulator and restorator; Bestatin promotes granulocytopoiesis and thrombocytopoiesis in vitro and restores them in myelo-hypoplastic men; (4 an inhibitor of several natural opioid peptides. Based on the knowledge that APN can cleave several bioactive neuropeptides such as Met-enkaphalins, Leu-enkaphalins, β-Endorphin, and so on, the antiaminopeptidase action of Bestatin also allows it to protect endopeptides against their catabolism, exhibiting analgesic activity. Although many scientific studies and great accomplishments have been achieved in this field, a large amount of problems are unsolved. This article reviews the promising results obtained for future development of the analgesic activity of Bestatin that can be of vital interest in a number of severe and chronic pain syndromes.

  18. Snake cathelicidin from Bungarus fasciatus is a potent peptide antibiotics.

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    Yipeng Wang

    Full Text Available BACKGROUND: Cathelicidins are a family of antimicrobial peptides acting as multifunctional effector molecules of innate immunity, which are firstly found in mammalians. Recently, several cathelicidins have also been found from chickens and fishes. No cathelicidins from other non-mammalian vertebrates have been reported. PRINCIPAL FINDINGS: In this work, a cathelicidin-like antimicrobial peptide named cathelicidin-BF has been purified from the snake venoms of Bungarus fasciatus and its cDNA sequence was cloned from the cDNA library, which confirm the presence of cathelicidin in reptiles. As other cathelicidins, the precursor of cathelicidin-BF has cathelin-like domain at the N terminus and carry the mature cathelicidin-BF at the C terminus, but it has an atypical acidic fragment insertion between the cathelin-like domain and the C-terminus. The acidic fragment is similar to acidic domains of amphibian antimicrobial precursors. Phylogenetic analysis revealed that the snake cathelicidin had the nearest evolution relationship with platypus cathelicidin. The secondary structure of cathelicidin-BF investigated by CD and NMR spectroscopy in the presence of the helicogenic solvent TFE is an amphipathic alpha-helical conformation as many other cathelicidins. The antimicrobial activities of cathelicidin BF against forty strains of microorganisms were tested. Cathelicidin-BF efficiently killed bacteria and some fungal species including clinically isolated drug-resistance microorganisms. It was especially active against Gram-negative bacteria. Furthermore, it could exert antimicrobial activity against some saprophytic fungus. No hemolytic and cytotoxic activity was observed at the dose of up to 400 microg/ml. Cathelicidin-BF could exist stably in the mice plasma for at least 2.5 hours. CONCLUSION: Discovery of snake cathelicidin with atypical structural and functional characterization offers new insights on the evolution of cathelicidins. Potent, broad

  19. Potent and specific antitumor effect of CEA-targeted photoimmunotherapy.

    Science.gov (United States)

    Shirasu, Naoto; Yamada, Hiromi; Shibaguchi, Hirotomo; Kuroki, Motomu; Kuroki, Masahide

    2014-12-01

    Conventional photodynamic therapy (PDT) for cancer is limited by the insufficient efficacy and specificity of photosensitizers. We herein describe a highly effective and selective tumor-targeted PDT using a near-infrared (NIR) photosensitizer, IRDye700DX, conjugated to a human monoclonal antibody (Ab) specific for carcinoembryonic antigen (CEA). The antitumor effects of this Ab-assisted PDT, called photoimmunotherapy (PIT), were investigated in vitro and in vivo. The Ab-IRDye conjugate induced potent cytotoxicity against CEA-positive tumor cells after NIR-irradiation, whereas CEA-negative cells were not affected at all, even in the presence of excess photoimmunoconjugate. We found an equivalent phototoxicity and a predominant plasma membrane localization of Ab-IRDye after both one and six hours of incubation. Either no or little caspase activation and membrane peroxidation were observed in PIT-treated cells and a panel of scavengers for reactive oxygen species showed only partial inhibition of the phototoxic effect. Strikingly, Ab-IRDye retained significant phototoxicity even under hypoxia. We established a xenograft model, which allowed us to sensitively investigate the therapeutic efficacy of PIT by non-invasive bioluminescence imaging. Luciferase-expressing MKN-45-luc human gastric carcinoma cells were subcutaneously implanted into both flanks of nude mice. NIR-irradiation was performed for only the tumor on one side. In vivo imaging and measurement of the tumor size revealed that a single PIT treatment, with intraperitoneal administration of Ab-IRDye and subsequent NIR-irradiation, caused rapid cell death and significant inhibition of tumor growth, but only on the irradiated side. Together, these data suggest that Ab-IRDye-mediated PIT has great potential as an anticancer therapeutics targeting CEA-positive tumors.

  20. Potent cytotoxic effects of Calomeria amaranthoides on ovarian cancers

    Directory of Open Access Journals (Sweden)

    van Haard Paul MM

    2011-03-01

    different, P = 0.13. Conclusions For the first time both crude plant extract from Calomeria amaranthoides and EPD have been shown to have potent anti-cancer effects against ovarian cancer.

  1. Discovery of potent anti-tuberculosis agents targeting leucyl-tRNA synthetase.

    Science.gov (United States)

    Gudzera, Olga I; Golub, Andriy G; Bdzhola, Volodymyr G; Volynets, Galyna P; Lukashov, Sergiy S; Kovalenko, Oksana P; Kriklivyi, Ivan A; Yaremchuk, Anna D; Starosyla, Sergiy A; Yarmoluk, Sergiy M; Tukalo, Michail A

    2016-03-01

    Tuberculosis is a serious infectious disease caused by human pathogen bacteria Mycobacterium tuberculosis. Bacterial drug resistance is a very significant medical problem nowadays and development of novel antibiotics with different mechanisms of action is an important goal of modern medical science. Leucyl-tRNA synthetase (LeuRS) has been recently clinically validated as antimicrobial target. Here we report the discovery of small-molecule inhibitors of M. tuberculosis LeuRS. Using receptor-based virtual screening we have identified six inhibitors of M. tuberculosis LeuRS from two different chemical classes. The most active compound 4-{[4-(4-Bromo-phenyl)-thiazol-2-yl]hydrazonomethyl}-2-methoxy-6-nitro-phenol (1) inhibits LeuRS with IC50 of 6μM. A series of derivatives has been synthesized and evaluated in vitro toward M. tuberculosis LeuRS. It was revealed that the most active compound 2,6-Dibromo-4-{[4-(4-nitro-phenyl)-thiazol-2-yl]-hydrazonomethyl}-phenol inhibits LeuRS with IC50 of 2.27μM. All active compounds were tested for antimicrobial effect against M. tuberculosis H37Rv. The compound 1 seems to have the best cell permeability and inhibits growth of pathogenic bacteria with IC50=10.01μM and IC90=13.53μM.

  2. Discovery of highly potent and selective type I B-Raf kinase inhibitors.

    Science.gov (United States)

    Wang, Xiaolun; Berger, Dan M; Salaski, Edward J; Torres, Nancy; Hu, Yongbo; Levin, Jeremy I; Powell, Dennis; Wojciechowicz, Donald; Collins, Karen; Frommer, Eileen

    2009-12-01

    A series of pyrazolo[1,5-alpha]pyrimidine analogs has been prepared and found to be potent and selective B-Raf inhibitors. Molecular modeling suggests they bind to the active conformation of the enzyme.

  3. Structure-based virtual screening campaigns on curcuminoids as potent ligands for histone deacetylase-2

    Directory of Open Access Journals (Sweden)

    Enade Perdana Istyastono

    2016-03-01

    Full Text Available Curcumin was reported to reverse the decrease in histone deacetylase-2 (HDAC2 protein expression in inflammatory diseases of the lung, including chronic obstructive pulmonary disease (COPD, severe asthma, and asthma in smokers. This indicates that curcumin is a potent ligand for HDAC2. The construction and retrospective validation of a structure-based virtual screening (SBVS protocol to identify potent ligands for HDAC2 are presented in this article. The validated protocol was subsequently employed to screen curcumin and other curcuminoids found in Curcuma longa, i.e. demethoxy curcumin and bis-demethoxy curcumin, and to examine their interactions to HDAC2 in the atomic level. The results show that curcumin, demethoxy curcumin and bis-demethoxy curcumin are potent HDAC2 ligands. The insights from their interactions to HDAC2 resulted from the molecular docking simulations presented in this article could be employed further in the design and discovery potent HDAC2 ligands.

  4. A concise total synthesis of (R)-fluoxetine, a potent and selective serotonin reuptake inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Fatima, Angelo de; Lapis, Alexandre Augusto M.; Pilli, Ronaldo A. [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica]. E-mail: pilli@iqm.unicamp.br

    2005-05-15

    (R)-Fluoxetine, potent and selective serotonin reuptake inhibitor, has been synthesized in six steps, 50% overall yield and 99% ee from benzaldehyde via catalytic asymmetric allylation with Maruoka's catalyst. (author)

  5. Total synthesis of a potent hybrid of the anticancer natural products dictyostatin and discodermolide.

    Science.gov (United States)

    Paterson, Ian; Naylor, Guy J; Wright, Amy E

    2008-10-14

    A potent dictyostatin-discodermolide hybrid was designed and synthesised; it showed enhanced cell growth inhibitory activity relative to discodermolide in four human cancer cell lines including the Taxol-resistant NCI/ADR-Res cell line.

  6. Synthesis and Evaluation of 2,4-Disubstituted Quinazoline Derivatives with Potent Anti-Angiogenesis Activities

    Directory of Open Access Journals (Sweden)

    Guangjin Yu

    2014-06-01

    Full Text Available A series of 2,4-disubstituted quinazoline derivatives were designed and synthesized. The biological results showed that most of quinazoline derivatives exhibited potent antiproliferative activities against a panel of three tumor cell lines and a good inhibitory effect against the adhesion and migration of human umbilical vein endothelial cells (HUVECs. Among these compounds, 11d was the most potent agent, that also exhibited the highest anti-angiogenesis activities in the chick embryo chorioallantoic membrane (CAM assay.

  7. Inhibition of steroidogenesis and induction of apoptosis in rat luteal cells by cell-permeable ceramide in vitro%细胞渗透性神经酰胺可抑制大鼠离体黄体细胞甾体激素生成并诱导细胞凋亡

    Institute of Scientific and Technical Information of China (English)

    李庆雷; 倪江; 边淑玲; 姚兰春; 朱辉; 张玮

    2001-01-01

    The present study was undertaken to investigate the effects of ceramide on progesterone production and apoptosis in rat luteal cells in vitro. Luteal cells were prepared from the ovaries of pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG) primed female Wistar rats and incubated with cell permeable C2-ceramide. The effects of ceramide on progesterone production and apoptosis in luteal cells were assessed by radio immunoassay (RIA) and flow cytometry analysis. In addition, changes in nitric oxide synthase (NOS) activity and nitric oxide (NO) production by luteal cells treated with C2-ceramide were also evaluated. Ceramide was found to reduce hCG-stimulated progesterone production in a dose-dependent manner, whereas it had little effect on basal progesterone content. Spontaneous apoptosis in luteal cells was observed after a 12-hour incubation in vitro and 5 μmol/L of ceramide significantly increased the apoptotic rate (P<0.05). Enhanced apoptotic peak was seen in the histogram by flow cytometry. Moreover, 50 μmol/L of C2-ceramide significantly increased NOS activity (P<0.01) and NO production (P<0.001). It is suggested that ceramide may serve as an important signaling molecule mediating certain ovarian processes, such as luteal regression.%本文旨在观察神经酰胺对离体孵育的大鼠黄体细胞孕酮分泌及细胞凋亡的影响。以PMSG-hCG处理的雌性Wistar大鼠为模型, 分离制备黄体细胞。将外源性细胞渗透性神经酰胺与黄体细胞共同孵育, 分别用放免法和流式细胞仪分析神经酰胺对黄体细胞孕酮生成和凋亡的影响,同时还检测了一氧化氮合酶 (NOS)活性和一氧化氮(NO)水平的变化。结果显示,神经酰胺可以剂量相关方式抑制hCG-诱导的孕酮分泌,而对基础孕酮没有显著影响。离体孵育12 h的大鼠黄体细胞存在自发性凋亡, 5 μmol/L神经酰胺能显著增加凋亡率(P<0.05), 流式细胞仪分析可见

  8. Evaluation of the Dmt-Tic pharmacophore: conversion of a potent delta-opioid receptor antagonist into a potent delta agonist and ligands with mixed properties.

    Science.gov (United States)

    Balboni, Gianfranco; Guerrini, Remo; Salvadori, Severo; Bianchi, Clementina; Rizzi, Daniela; Bryant, Sharon D; Lazarus, Lawrence H

    2002-01-31

    Analogues of the 2',6'-dimethyl-L-tyrosine (Dmt)-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) pharmacophore were prepared to test the hypothesis that a "spacer" and a third aromatic center in opioid peptides are required to convert a delta-antagonist into ligands with delta-agonist or with mixed delta-antagonist/mu-agonist properties. Potent delta-agonists and bifunctional compounds with high delta- and mu-opioid receptor affinities were obtained by varying the spacer length [none, NH-CH(2), NH-CH(2)-CH(2), Gly-NH-CH(2)] and C-terminal aromatic nucleus [1H-benzimidazole-2-yl, phenyl (Ph) and benzyl groups]. C-terminal modification primarily affected mu-opioid receptor affinities, which increased maximally 1700-fold relative to the prototype delta-antagonist H-Dmt-Tic-NH(2) and differentially modified bioactivity. In the absence of a spacer (1), the analogue exhibited dual delta-agonism (pEC(50), 7.28) and delta-antagonism (pA(2), 7.90). H-Dmt-Tic-NH-CH(2)-1H-benzimidazole-2-yl (Bid) (2) became a highly potent delta-agonist (pEC(50), 9.90), slightly greater than deltorphin C (pEC(50), 9.56), with mu-agonism (pE(50), 7.57), while H-Dmt-Tic-Gly-NH-CH(2)-Bid (4) retained potent delta-antagonism (pA(2), 9.0) but with an order of magnitude less mu-agonism. Similarly, H-Dmt-Tic-Gly-NH-Ph (5) had nearly equivalent high delta-agonism (pEC(50), 8.52) and mu-agonism (pEC(50), 8.59), while H-Dmt-Tic-Gly-NH-CH(2)-Ph (6) whose spacer was longer by a single methylene group exhibited potent delta-antagonism (pA(2), 9.25) and very high mu-agonism (pEC(50), 8.57). These data confirm that the distance between the Dmt-Tic pharmacophore and a third aromatic nucleus is an important criterion in converting Dmt-Tic from a highly potent delta-antagonist into a potent delta-agonist or into ligands with mixed delta- and mu-opioid properties.

  9. New potent and selective polyfluoroalkyl ketone inhibitors of GVIA calcium-independent phospholipase A2.

    Science.gov (United States)

    Magrioti, Victoria; Nikolaou, Aikaterini; Smyrniotou, Annetta; Shah, Ishita; Constantinou-Kokotou, Violetta; Dennis, Edward A; Kokotos, George

    2013-09-15

    Group VIA calcium-independent phospholipase A2 (GVIA iPLA2) has recently emerged as an important pharmaceutical target. Selective and potent GVIA iPLA2 inhibitors can be used to study its role in various neurological disorders. In the current work, we explore the significance of the introduction of a substituent in previously reported potent GVIA iPLA2 inhibitors. 1,1,1,2,2-Pentafluoro-7-(4-methoxyphenyl)heptan-3-one (GK187) is the most potent and selective GVIA iPLA2 inhibitor ever reported with a XI(50) value of 0.0001, and with no significant inhibition against GIVA cPLA2 or GV sPLA2. We also compare the inhibition of two difluoromethyl ketones on GVIA iPLA2, GIVA cPLA2, and GV sPLA2. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Combining Elements from Two Antagonists of Formyl Peptide Receptor 2 Generates More Potent Peptidomimetic Antagonists.

    Science.gov (United States)

    Skovbakke, Sarah Line; Holdfeldt, André; Nielsen, Christina; Hansen, Anna Mette; Perez-Gassol, Iris; Dahlgren, Claes; Forsman, Huamei; Franzyk, Henrik

    2017-08-24

    Structural optimization of a peptidomimetic antagonist of formyl peptide receptor 2 (FPR2) was explored by an approach involving combination of elements from the two most potent FPR2 antagonists described: a Rhodamine B-conjugated 10-residue gelsonin-derived peptide (i.e., PBP10, RhB-QRLFQVKGRR-OH) and the palmitoylated α-peptide/β-peptoid hybrid Pam-(Lys-βNspe)6-NH2. This generated an array of hybrid compounds from which a new subclass of receptor-selective antagonists was identified. The most potent representatives displayed activity in the low nanomolar range. The resulting stable and potent FPR2-selective antagonists (i.e., RhB-(Lys-βNphe)n-NH2; n = 4-6) are expected to become valuable tools in further elucidation of the physiological role of FPR2 in health and disease.

  11. Thioester derivatives of the natural product psammaplin A as potent histone deacetylase inhibitors

    Directory of Open Access Journals (Sweden)

    Matthias G. J. Baud

    2013-01-01

    Full Text Available There has been significant interest in the bioactivity of the natural product psammaplin A, most recently as a potent and isoform selective HDAC inhibitor. Here we report our preliminary studies on thioester HDAC inhibitors derived from the active monomeric (thiol form of psammaplin A, as a means to improve compound delivery into cells. We have discovered that such compounds exhibit both potent cytotoxicity and enzymatic inhibitory activity against recombinant HDAC1. The latter effect is surprising since previous SAR suggested that modification of the thiol functionality should detrimentally affect HDAC potency. We therefore also report our preliminary studies on the mechanism of action of this observed effect.

  12. Substituted tetrahydroquinolines as potent allosteric inhibitors of reverse transcriptase and its key mutants

    Energy Technology Data Exchange (ETDEWEB)

    Su, Dai-Shi; Lim, John J.; Tinney, Elizabeth; Wan, Bang-Lin; Young, Mary Beth; Anderson, Kenneth D.; Rudd, Deanne; Munshi, Vandna; Bahnck, Carolyn; Felock, Peter J.; Lu, Meiqing; Lai, Ming-Tain; Touch, Sinoeun; Moyer, Gregory; DiStefano, Daniel J.; Flynn, Jessica A.; Liang, Yuexia; Sanchez, Rosa; Prasad, Sridhar; Yan, Youwei; Perlow-Poehnelt, Rebecca; Torrent, Maricel; Miller, Mike; Vacca, Joe P.; Williams, Theresa M.; Anthony, Neville J.; Merck

    2010-09-27

    Non-nucleoside reverse transcriptase inhibitors (NNRTIs) are key elements of multidrug regimens, called HAART (Highly Active Antiretroviral Therapy), that are used to treat HIV-1 infections. Elucidation of the structure-activity relationships of the thiocarbamate moiety of the previous published lead compound 2 provided a series of novel tetrahydroquinoline derivatives as potent inhibitors of HIV-1 RT with nanomolar intrinsic activity on the WT and key mutant enzymes and potent antiviral activity in infected cells. The SAR optimization, mutation profiles, preparation of compounds, and pharmacokinetic profile of compounds are described.

  13. The discovery of novel benzofuran-2-carboxylic acids as potent Pim-1 inhibitors.

    Science.gov (United States)

    Xiang, Yibin; Hirth, Bradford; Asmussen, Gary; Biemann, Hans-Peter; Bishop, Kimberly A; Good, Andrew; Fitzgerald, Maria; Gladysheva, Tatiana; Jain, Annuradha; Jancsics, Katherine; Liu, Jinyu; Metz, Markus; Papoulis, Andrew; Skerlj, Renato; Stepp, J David; Wei, Ronnie R

    2011-05-15

    Novel benzofuran-2-carboxylic acids, exemplified by 29, 38 and 39, have been discovered as potent Pim-1 inhibitors using fragment based screening followed by X-ray structure guided medicinal chemistry optimization. The compounds demonstrate potent inhibition against Pim-1 and Pim-2 in enzyme assays. Compound 29 has been tested in the Ambit 442 kinase panel and demonstrates good selectivity for the Pim kinase family. X-ray structures of the inhibitor/Pim-1 binding complex reveal important salt-bridge and hydrogen bond interactions mediated by the compound's carboxylic acid and amino groups.

  14. Discovery of indole-based tetraarylimidazoles as potent inhibitors of urease with low antilipoxygenase activity.

    Science.gov (United States)

    Naureen, Sadia; Chaudhry, Faryal; Asif, Nadia; Munawar, Munawar Ali; Ashraf, Muhammad; Nasim, Faizul Hassan; Arshad, Humera; Khan, Misbahul Ain

    2015-09-18

    A series of tetraarylimidazoles (5A-5O) were prepared by one pot four component condensation reactions of 2-arylindole-3-carbaldehydes, substituted anilines, benzil and ammonium acetate in acetic acid. The synthesized compounds exhibited potent antiurease activity with IC50 values ranging from 0.12 ± 0.06 μM to 29.12 ± 0.18 μM as compared with thiourea. However, low inhibition profiles were observed for lipoxygenase. The data show that tetraarylimidazoles containing a substituted 2-penylindole have emerged as a new class of potent inhibitors of urease enzyme.

  15. Synthesis and structure-activity relationships of potent 4-fluoro-2-cyanopyrrolidine dipeptidyl peptidase IV inhibitors.

    Science.gov (United States)

    Fukushima, Hiroshi; Hiratate, Akira; Takahashi, Masato; Mikami, Ayako; Saito-Hori, Masako; Munetomo, Eiji; Kitano, Kiyokazu; Chonan, Sumi; Saito, Hidetaka; Suzuki, Akio; Takaoka, Yuji; Yamamoto, Koji

    2008-04-01

    Dipeptidyl peptidase IV (DPP-IV) inhibitors are promising antidiabetic drugs, and several drugs are in the developmental stage. We previously reported that the introduction of fluorine to the 4-position of 2-cyanopyrrolidine enhanced the DPP-IV inhibitory effect. In the present report, we examined the structure-activity relationship (SAR) of 2-cyano-4-fluoropyrrolidine with N-substituted glycine at the 1-position. We report the identification of a potent and stable DPP-IV inhibitor (TS-021) with a long-term persistent plasma drug concentration and a potent antihyperglycemic activity.

  16. Discovery of a Potent and Selective BCL-XL Inhibitor with in Vivo Activity.

    Science.gov (United States)

    Tao, Zhi-Fu; Hasvold, Lisa; Wang, Le; Wang, Xilu; Petros, Andrew M; Park, Chang H; Boghaert, Erwin R; Catron, Nathaniel D; Chen, Jun; Colman, Peter M; Czabotar, Peter E; Deshayes, Kurt; Fairbrother, Wayne J; Flygare, John A; Hymowitz, Sarah G; Jin, Sha; Judge, Russell A; Koehler, Michael F T; Kovar, Peter J; Lessene, Guillaume; Mitten, Michael J; Ndubaku, Chudi O; Nimmer, Paul; Purkey, Hans E; Oleksijew, Anatol; Phillips, Darren C; Sleebs, Brad E; Smith, Brian J; Smith, Morey L; Tahir, Stephen K; Watson, Keith G; Xiao, Yu; Xue, John; Zhang, Haichao; Zobel, Kerry; Rosenberg, Saul H; Tse, Chris; Leverson, Joel D; Elmore, Steven W; Souers, Andrew J

    2014-10-09

    A-1155463, a highly potent and selective BCL-XL inhibitor, was discovered through nuclear magnetic resonance (NMR) fragment screening and structure-based design. This compound is substantially more potent against BCL-XL-dependent cell lines relative to our recently reported inhibitor, WEHI-539, while possessing none of its inherent pharmaceutical liabilities. A-1155463 caused a mechanism-based and reversible thrombocytopenia in mice and inhibited H146 small cell lung cancer xenograft tumor growth in vivo following multiple doses. A-1155463 thus represents an excellent tool molecule for studying BCL-XL biology as well as a productive lead structure for further optimization.

  17. Characterization of typical potent odorants in cola-flavored carbonated beverages by aroma extract dilution analysis.

    Science.gov (United States)

    Lorjaroenphon, Yaowapa; Cadwallader, Keith R

    2015-01-28

    The aroma-active compounds in typical cola-flavored carbonated beverages were characterized using gas chromatography-olfactometry and gas chromatography-mass spectrometry. The potent odorants in the top three U.S. brands of regular colas were identified by aroma extract dilution analysis (AEDA). Among the numerous odorants identified, eugenol (spicy, clovelike, sweet) and coumarin (sweet, herbaceous) were predominant in all colas. Other predominant odorants in at least one brand included guaiacol (smoky) and linalool (floral, sweet), while 1,8-cineole (minty, eucalyptus-like) was a moderately potent odorant in all colas. Determination of the enantiomeric compositions indicated that (R)-(-)-linalool (34.5%) was a more potent odorant than the (S)-(+)-enantiomer (65.6%) due to its much lower odor detection threshold. In addition, lemon-lime and cooling attributes determined by sensory descriptive analysis had the highest odor intensities among the eight sensory descriptors. The aroma profiles of the three colas were in good agreement with the potent odorants identified by AEDA.

  18. A concise synthesis of the potent inflammatory mediator 5-oxo-ETE

    DEFF Research Database (Denmark)

    Tyagi, Rahul; Shimpukade, Bharat; Blättermann, Stefanie

    2012-01-01

    A concise and practical method for synthesis of the potent inflammatory mediator 5-oxo-6E,8Z,11Z,14Z-eicosatetraenoic acid (5-oxo-ETE, 1) from arachidonic acid in four steps and 70% overall yield is reported. Stability studies indicate that 1 can be safely handled without rigorous precautions...

  19. Urolithins, Intestinal Microbial Metabolites of Pomegranate Ellagitannins, Exhibit Potent Antioxidant Activity in Cell-Based Assay

    Science.gov (United States)

    Many health benefits of pomegranate products have been attributed to the potent antioxidant action of their tannin components, mainly punicalagins and ellagic acid. While moving through the intestines, ellagitannins are metabolized by gut bacteria into urolithins that readily enter systemic circulat...

  20. Synthesis and evaluation of heteroarylalanine diacids as potent and selective neutral endopeptidase inhibitors.

    Science.gov (United States)

    Glossop, Melanie S; Bazin, Richard J; Dack, Kevin N; Fox, David N A; MacDonald, Graeme A; Mills, Mark; Owen, Dafydd R; Phillips, Chris; Reeves, Keith A; Ringer, Tracy J; Strang, Ross S; Watson, Christine A L

    2011-06-01

    Heteroarylalanine derivatives 4 were designed as potential inhibitors of neutral endopeptidase (NEP EC 3.4.24.11). Selectivity over other zinc metalloproteinases was explored through occupation of the S2' subsite within NEP. Structural optimisation led to the identification of 5-phenyl oxazole 4f, a potent and selective NEP inhibitor. A crystal structure of the inhibitor bound complex is reported.

  1. Design, Synthesis, Molecular Docking, and Antibacterial Evaluation of Some Novel Flouroquinolone Derivatives as Potent Antibacterial Agent

    Directory of Open Access Journals (Sweden)

    Mehul M. Patel

    2014-01-01

    Full Text Available Objective. Quinolone moiety is an important class of nitrogen containing heterocycles widely used as key building blocks for medicinal agents. It exhibits a wide spectrum of pharmacophores and has bactericidal, antiviral, antimalarial, and anticancer activities. In view of the reported antimicrobial activity of various fluoroquinolones, the importance of the C-7 substituents is that they exhibit potent antimicrobial activities. Our objective was to synthesize newer quinolone analogues with increasing bulk at C-7 position of the main 6-fluoroquinolone scaffold to produce the target compounds which have potent antimicrobial activity. Methods. A novel series of 1-ethyl-6-fluoro-4-oxo-7-{4-[2-(4-substituted phenyl-2-(substituted-ethyl]-1-piperazinyl}-1,4-dihydroquinoline-3-carboxylic acid derivatives were synthesized. To understand the interaction of binding sites with bacterial protein receptor, the docking study was performed using topoisomerase II DNA gyrase enzymes (PDB ID: 2XCT by Schrodinger’s Maestro program. In vitro antibacterial activity of the synthesized compounds was studied and the MIC value was calculated by the broth dilution method. Results. Among all the synthesized compounds, some compounds showed potent antimicrobial activity. The compound 8g exhibited good antibacterial activity. Conclusion. This investigation identified the potent antibacterial agents against certain infections.

  2. Radiosynthesis and characterisation of a potent and selective GPR139 agonist radioligand

    DEFF Research Database (Denmark)

    Kuhne, Sebastiaan; Nøhr, Anne Cathrine; Marek, AleŠ;

    2016-01-01

    Compound 1 is a selective and potent agonist of the G protein-coupled receptor GPR139 (EC50 = 39 nM). In this study, we describe the synthesis, radiolabelling and in vitro evaluation of [3H]-1 for the characterisation of GPR139 and its spatial expression in the brain using autoradiography. Two di...

  3. Bicyclic isoureas derived from 1-deoxynojirimycin are potent inhibitors of β-glucocerebrosidase

    NARCIS (Netherlands)

    Sevšek, Alen; Čelan, Maša; Erjavec, Bibi; Quarles van Ufford, Linda; Sastre Toraño, Javier; Moret, Ed E; Pieters, Roland J; Martin, Nathaniel I

    2016-01-01

    A series of bicyclic isourea derivatives were prepared from 1-deoxynojirimycin using a concise synthetic protocol proceeding via a guanidino intermediate. Inhibition assays with a panel of glycosidases revealed that these deoxynojirimycin-derived bicyclic isoureas display very potent inhibition agai

  4. Novel, potent, selective, and orally bioavailable human betaII-tryptase inhibitors.

    Science.gov (United States)

    Sperandio, David; Tai, Vincent W-F; Lohman, Julia; Hirschbein, Bernie; Mendonca, Rohan; Lee, Chang-Sun; Spencer, Jeffrey R; Janc, James; Nguyen, Margaret; Beltman, Jerlyn; Sprengeler, Paul; Scheerens, Heleen; Lin, Tong; Liu, Liang; Gadre, Ashwini; Kellogg, Alisha; Green, Michael J; McGrath, Mary E

    2006-08-01

    The synthesis of novel [1,2,4]oxadiazoles and their structure-activity relationship (SAR) for the inhibition of tryptase and related serine proteases is presented. Elaboration of the P'-side afforded potent, selective, and orally bioavailable tryptase inhibitors.

  5. Production of Potent Fully Human Polyclonal Antibodies Against Zaire Ebola Virus in Transchromosomal Cattle

    Science.gov (United States)

    2016-07-01

    1 Production of potent fully human polyclonal antibodies against Zaire Ebola virus in transchromosomal cattle John M. Dye1, Hua Wu2, Jay...mail: jjiao@sabbiotherapeutics.com Keywords: Ebola virus, virus neutralization assay, human polyclonal antibodies, transchromosomal bovine...recombinant glycoprotein (GP) vaccine consisting of the 2014 Ebola virus (EBOV)-Makona isolate. Serum collected from these hyperimmunized Tc

  6. An Amphotericin B Derivative Equally Potent to Amphotericin B and with Increased Safety

    NARCIS (Netherlands)

    Antillón, Armando; De Vries, Alexander H.; Espinosa-caballero, Marcel; Falcón-gonzález, José Marcos; Flores Romero, David; González–damián, Javier; Jiménez-montejo, Fabiola Eloísa; León-buitimea, Angel; López-ortiz, Manuel; Magaña, Ricardo; Marrink, Siewert J.; Morales-nava, Rosmarbel; Periole, Xavier; Reyes-esparza, Jorge; Rodríguez Lozada, Josué; Santiago-angelino, Tania Minerva; Vargas González, María Cristina; Regla, Ignacio; Carrillo-tripp, Mauricio; Fernández-zertuche, Mario; Rodríguez-fragoso, Lourdes; Ortega-blake, Iván; Johnson, Christopher James

    2016-01-01

    Amphotericin B is the most potent antimycotic known to date. However due to its large col- lateral toxicity, its use, although long standing, had been limited. Many attempts have been made to produce derivatives with reduced collateral damage. The molecular mechanism of polyene has also been closely

  7. Molecular engineered super-nanodevices: smart and safe delivery of potent drugs into tumors.

    Science.gov (United States)

    Ding, Mingming; Li, Jiehua; He, Xueling; Song, Nijia; Tan, Hong; Zhang, Yi; Zhou, Lijuan; Gu, Qun; Deng, Hua; Fu, Qiang

    2012-07-17

    A super-nanodevice engineered at molecular level integrates various desired properties in a smart and coordinated way, and can "switch on" or "turn off" certain functionalities as required. Importantly, it can break through complex physiological barriers, and then precisely ferry potent toxic triptolide into tumor cells in vivo, thus significantly maximizing the therapeutic efficacy and reducing the drug toxicity.

  8. Pyrrolidin-3-yl-N-methylbenzamides as potent histamine 3 receptor antagonists.

    Science.gov (United States)

    Zhou, Dahui; Gross, Jonathan L; Sze, Jean Y; Adedoyin, Adedayo B; Bowlby, Mark; Di, Li; Platt, Brian J; Zhang, Guoming; Brandon, Nicholas; Comery, Thomas A; Robichaud, Albert J

    2011-10-01

    On the basis of the previously reported benzimidazole 1,3'-bipyrrolidine benzamides (1), a series of related pyrrolidin-3-yl-N-methylbenzamides were synthesized and evaluated as H(3) receptor antagonists. In particular, compound 32 exhibits potent H(3) receptor binding affinity, improved pharmaceutical properties and a favorable in vivo profile.

  9. A concise synthesis of the potent inflammatory mediator 5-oxo-ETE

    DEFF Research Database (Denmark)

    Tyagi, Rahul; Shimpukade, Bharat; Blättermann, Stefanie;

    2012-01-01

    A concise and practical method for synthesis of the potent inflammatory mediator 5-oxo-6E,8Z,11Z,14Z-eicosatetraenoic acid (5-oxo-ETE, 1) from arachidonic acid in four steps and 70% overall yield is reported. Stability studies indicate that 1 can be safely handled without rigorous precautions...

  10. Development and Characterization of a Potent Free Fatty Acid Receptor 1 (FFA1) Fluorescent Tracer

    DEFF Research Database (Denmark)

    Christiansen, Elisabeth; Hudson, Brian D; Hansen, Anders Højgaard;

    2016-01-01

    The free fatty acid receptor 1 (FFA1/GPR40) is a potential target for treatment of type 2 diabetes. Although several potent agonists have been described, there remains a strong need for suitable tracers to interrogate ligand binding to this receptor. We address this by exploring fluorophore-tethe...

  11. Psymberin, a potent sponge-derived cytotoxin from Psammocinia distantly related to the pederin family.

    Science.gov (United States)

    Cichewicz, Robert H; Valeriote, Frederick A; Crews, Phillip

    2004-06-10

    [structure: see text] Bioassay-guided fractionation of the sponge Psammocinia sp. afforded psymberin (1) possessing 5S,8S,9S,11R,13R,15S,16R,17R stereochemistry. Psymberin exhibits structural similarities to the pederin family metabolites. The potent cytotoxicty and unique structural features of 1 make it a promising lead for therapeutic development.

  12. An Amphotericin B Derivative Equally Potent to Amphotericin B and with Increased Safety

    NARCIS (Netherlands)

    Antillón, Armando; De Vries, Alexander H.; Espinosa-caballero, Marcel; Falcón-gonzález, José Marcos; Flores Romero, David; González–damián, Javier; Jiménez-montejo, Fabiola Eloísa; León-buitimea, Angel; López-ortiz, Manuel; Magaña, Ricardo; Marrink, Siewert J.; Morales-nava, Rosmarbel; Periole, Xavier; Reyes-esparza, Jorge; Rodríguez Lozada, Josué; Santiago-angelino, Tania Minerva; Vargas González, María Cristina; Regla, Ignacio; Carrillo-tripp, Mauricio; Fernández-zertuche, Mario; Rodríguez-fragoso, Lourdes; Ortega-blake, Iván; Johnson, Christopher James

    2016-01-01

    Amphotericin B is the most potent antimycotic known to date. However due to its large col- lateral toxicity, its use, although long standing, had been limited. Many attempts have been made to produce derivatives with reduced collateral damage. The molecular mechanism of polyene has also been closely

  13. Potent Systemic Anticancer Activity of Adenovirally Expressed EGFR-Selective TRAIL Fusion Protein

    NARCIS (Netherlands)

    Bremer, Edwin; van Dam, Gooitzen M.; de Bruyn, Marco; van Riezen, Manon; Dijkstra, Marike; Kamps, Gera; Helfrich, Wijnand; Haisma, Hidde

    2008-01-01

    Previously, we demonstrated potent tumor cell-selective pro-apoptotic activity of scFv425:sTRAIL, a recombinant fusion protein comprised of EGFR-directed antibody fragment (scFv425) genetically fused to human soluble TNF-related apoptosis-inducing ligand (sTRAIL). Here, we report on the promising th

  14. Pharmacokinetics and tolerability of cediranib, a potent VEGF signalling inhibitor, in cancer patients with hepatic impairment

    DEFF Research Database (Denmark)

    van Herpen, Carla M L; Lassen, Ulrik; Desar, Ingrid M E

    2013-01-01

    Vascular endothelial growth factor (VEGF) signalling plays a key role in tumour angiogenesis. Cediranib (AZD2171) is a small-molecule VEGF signalling inhibitor with potent activity against all three VEGF receptors. In this phase I, open-label, parallel-group study, adults with advanced solid tumo...

  15. Synthesis and biological evaluation of andrographolide derivatives as potent anti-HIV agents

    Institute of Scientific and Technical Information of China (English)

    Bin Wang; Jing Li; Wen Long Huang; Hui Bin Zhang; Hai Qian; Yong Tang Zheng

    2011-01-01

    A series of Andro derivatives were described and evaluated for their anti-HIV activity in vitro. Compound 10 and 16b, of which TI were >10, had some anti-HTV-1 activity in vitro. Therein, compound 10 which was the best potent compound, could serve as a new lead for further development of anti-AIDS agents.

  16. Whole body application of a potent topical corticosteroid for bullous pemphigoid

    NARCIS (Netherlands)

    Terra, J. B.; Potze, W. J. B.; Jonkman, M. F.

    BackgroundCurrent standard of treatment of bullous pemphigoid (BP) is systemic oral corticosteroids (CS). However, significant iatrogenic morbidity and mortality is reported. Studies have shown that topical potent CS is safer than oral prednisolone in BP. ObjectivesTo examine the local and systemic

  17. Pharmacokinetics and tolerability of cediranib, a potent VEGF signalling inhibitor, in cancer patients with hepatic impairment

    NARCIS (Netherlands)

    Herpen, C.M.L. van; Lassen, U.; Desar, I.M.E.; Brown, K.H.; Marotti, M.; Jonge, M.J. de

    2013-01-01

    Vascular endothelial growth factor (VEGF) signalling plays a key role in tumour angiogenesis. Cediranib (AZD2171) is a small-molecule VEGF signalling inhibitor with potent activity against all three VEGF receptors. In this phase I, open-label, parallel-group study, adults with advanced solid tumours

  18. Teratogenicity studies of a new potent tetanus vaccine in rabbit (Oryctolagus cuniculus).

    Science.gov (United States)

    Sethi, N; Srivastava, R K; Singh, R K

    1991-09-01

    Glaxo Laboratories, Bombay, have prepared a potent tetanus vaccine of 250 Lf as a substitute of the previous 5 Lf tetanus vaccine. The safety evaluation of the vaccine has been reported, but the teratogenic potential was not studied. In the experiment reported herein we have studied the teratogenic action of the vaccine in the progeny of rabbits. No congenital anomalies were observed.

  19. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  20. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  1. Chloroatranol, an extremely potent allergen hidden in perfumes: a dose-response elicitation study

    DEFF Research Database (Denmark)

    Johansen, Jeanne Duus; Andersen, Klaus Ejner; Svedman, Cecilia;

    2003-01-01

    Oak moss absolute is a long-known, popular natural extract widely used in perfumes. It is reported as the cause of allergic reactions in a significant number of those with perfume allergy. Oak moss absolute has been the target of recent research to identify its allergenic components. Recently......, chloroatranol, a hitherto unknown fragrance allergen, was identified in oak moss absolute. The objective was to assess the clinical importance of chloroatranol as a fragrance allergen by characterizing its elicitation profile. 13 patients previously showing a positive patch test to oak moss absolute....... The dose eliciting a reaction in 50% of the test subjects at patch testing was 0.2 p.p.m. In conclusion, the hidden exposure to a potent allergen widely used in perfumes has caused a highly sensitized cohort of individuals. Judged from the elicitation profile, chloroatranol is the most potent allergen...

  2. Biological evaluation of potent antioxidant, lipoxygenase inhibitor and antibacterial: A comparative study

    Directory of Open Access Journals (Sweden)

    Muhammad Aslam

    2016-01-01

    Full Text Available Three biologically active new Schiff bases, 2-[(3-hydroxybenzylideneamino]phenol 5, 2-[(4-hydroxybenzylideneamino]phenol 6 and 4-[(2-hydroxyphenyliminomethyl]benzene-1,3-diol 7, were synthesized by the reaction of 2-aminophenol 1 with three different hydroxyl-benzaldehydes 2–4. They were characterized by spectroscopic analysis (IR, 1H NMR, EI-MS along with elemental analyses. The products were biological screened out for antioxidant, lipoxygenase inhibition, antibacterial and urease inhibition activities. The compounds 5 and 6 showed potent while 7 showed moderate antioxidant activity. Compound 6 showed potent whereas 5 and 7 showed significant lipoxygenase inhibition activity. All the target compounds showed excellent activities against Staphylococcus intermedius, Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Salmonella typhi bacteria. All the compounds showed non-significant activity against urease enzyme.

  3. Resveratrol: cellular actions of a potent natural chemical that confers a diversity of health benefits.

    Science.gov (United States)

    Marques, Francine Z; Markus, M Andrea; Morris, Brian J

    2009-11-01

    Resveratrol is a polyphenolic flavonoid with potent antioxidant activity. It is found in a diversity of plants, notably berry fruit, and is attracting increased attention due to its health benefits, especially in common age-related diseases such as cancer, type 2 diabetes, cardiovascular disease, and neurological conditions. Resveratrol has positive effects on metabolism and can increase the lifespan of various organisms. Its effects arise from its capacity to interact with multiple molecular targets involved in diverse intracellular pathways. Most well known is the ability of resveratrol to activate sirtuins, a class of NAD(+)-dependent deacetylases that affect multiple transcription factors and other protein targets. More potent sirtuin activators have now been discovered by large-scale screening programs. Resveratrol and the new compounds are the subject of clinical trials to determine their consumer safety and suitability for the prevention and treatment of most common diseases of aging.

  4. Oxime Ethers of (E)-11-Isonitrosostrychnine as Highly Potent Glycine Receptor Antagonists

    DEFF Research Database (Denmark)

    Mohsen, Amal M Y; Mandour, Yasmine M; Sarukhanyan, Edita

    2016-01-01

    A series of (E)-11-isonitrosostrychnine oxime ethers, 2-aminostrychnine, (strychnine-2-yl)propionamide, 18-oxostrychnine, and N-propylstrychnine bromide were synthesized and evaluated pharmacologically at human α1 and α1β glycine receptors in a functional fluorescence-based and a whole-cell patch......-clamp assay and in [(3)H]strychnine binding studies. 2-Aminostrychnine and the methyl, allyl, and propargyl oxime ethers were the most potent α1 and α1β antagonists in the series, displaying IC50 values similar to those of strychnine at the two receptors. Docking experiments to the strychnine binding site...... of the crystal structure of the α3 glycine receptor indicated the same orientation of the strychnine core for all analogues. For the most potent oxime ethers, the ether substituent was accommodated in a lipophilic receptor binding pocket. The findings identify the oxime hydroxy group as a suitable attachment...

  5. Green synthesis and characterization of gold nanoparticles using extract of anti-tumor potent Crocus sativus

    Science.gov (United States)

    Vijayakumar, R.; Devi, V.; Adavallan, K.; Saranya, D.

    2011-12-01

    In the present study, we have explored anti-tumor potent Crocus sativus (saffron) as a reducing agent for one pot size controlled green synthesis of gold nanoparticles (AuNps) at ambient conditions. The nanoparticles were characterized using UV-vis, scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and FTIR analysis. The prepared AuNPs showed surface Plasmon resonance centered at 549 nm with average particle size of 15±5 nm. Stable, spherical and triangular crystalline AuNPs with well-defined dimensions were synthesized using anti-tumor potent Crocus sativus (saffron). Crystalline nature of the nanoparticles is confirmed from the HR-TEM, SAED and SEM images, and XRD patterns. From the FTIR spectra it is found that the biomolecules are responsible for capping in gold nanoparticles.

  6. Tranylcypromine substituted cis-hydroxycyclobutylnaphthamides as potent and selective dopamine D₃ receptor antagonists.

    Science.gov (United States)

    Chen, Jianyong; Levant, Beth; Jiang, Cheng; Keck, Thomas M; Newman, Amy Hauck; Wang, Shaomeng

    2014-06-12

    We report a class of potent and selective dopamine D3 receptor antagonists based upon tranylcypromine. Although tranylcypromine has a low affinity for the rat D3 receptor (K(i) = 12.8 μM), our efforts have yielded (1R,2S)-11 (CJ-1882), which has K(i) values of 2.7 and 2.8 nM at the rat and human dopamine D3 receptors, respectively, and displays respective selectivities of >10000-fold and 223-fold over the rat and human D2 receptors. Evaluation in a β-arrestin functional assay showed that (1R,2S)-11 is a potent and competitive antagonist at the human D3 receptor.

  7. Design, synthesis and evaluation of 5-substituted 1-H-tetrazoles as potent anticonvulsant agents.

    Science.gov (United States)

    Liao, Ai-Mei; Wang, Tiantian; Cai, Bangrong; Jin, Yi; Cheon, Seunghoon; Chun, ChangJu; Wang, Zengtao

    2017-04-01

    A series of 5-substituted 1-H-tetrazoles were designed and synthesized as potent anticonvulsant agents. Their preliminary anticonvulsant activities were evaluated using maximal electroshock and subcutaneous pentylenetetrazole (scPTZ) seizure tests. Neurotoxicity was determined using rotarod test. The results indicated that the compound 2j in scPTZ model exhibited the ED50 values of 83.3 mg/kg, superior to the standard drug ethosuximide with the maximum activity. In addition, compound 2k showed the most potent activity in MES model with ED50 value of 9.6 mg/kg and TD50 value of 189.5 mg/kg after intraperitoneal injection in mice, and displayed a high protective index (TD50/ED50) of 19.7 compared to reference antiepileptic drugs.

  8. Fragment-based discovery of potent inhibitors of the anti-apoptotic MCL-1 protein.

    Science.gov (United States)

    Petros, Andrew M; Swann, Steven L; Song, Danying; Swinger, Kerren; Park, Chang; Zhang, Haichao; Wendt, Michael D; Kunzer, Aaron R; Souers, Andrew J; Sun, Chaohong

    2014-03-15

    Apoptosis is regulated by the BCL-2 family of proteins, which is comprised of both pro-death and pro-survival members. Evasion of apoptosis is a hallmark of malignant cells. One way in which cancer cells achieve this evasion is thru overexpression of the pro-survival members of the BCL-2 family. Overexpression of MCL-1, a pro-survival protein, has been shown to be a resistance factor for Navitoclax, a potent inhibitor of BCL-2 and BCL-XL. Here we describe the use of fragment screening methods and structural biology to drive the discovery of novel MCL-1 inhibitors from two distinct structural classes. Specifically, cores derived from a biphenyl sulfonamide and salicylic acid were uncovered in an NMR-based fragment screen and elaborated using high throughput analog synthesis. This culminated in the discovery of selective and potent inhibitors of MCL-1 that may serve as promising leads for medicinal chemistry optimization efforts.

  9. Total Synthesis of a Highly Potent Anticancer Natural Product OSW-1

    Institute of Scientific and Technical Information of China (English)

    Zhendong; Jin

    2001-01-01

    OSW-1 (1) and its four natural analogs (2-5) are five highly potent anticancer natural products that were recently isolated from the bulbs of Ornithogalum saundersiae, a perennial grown in southern Africa (Figure 1).1 The IC50 values of these compounds against human promyelocytic leukemia HL-60 cells range from between 0.1 to 0.3 nM.2 Their anticancer activities are from 10 to 100 times more potent than other well-known anticancer agents in clinical use, including mitomycin C, adriamycin, cisplatin, camptothecin, and taxol. OSW-1 (1), the main constituent of Ornithogalum saundersiae bulbs, is highly cytostatic in the NCI 60-cell in vitro screen, with a mean IC50 of 0.78 nM. It also looks promising from in vivo tests against mouse P388 leukemia (increased life span 59%) by a one-time administration of 0.01 mg/kg.  ……

  10. "Appearance potent"? A content analysis of UK gay and straight men's magazines.

    Science.gov (United States)

    Jankowski, Glen S; Fawkner, Helen; Slater, Amy; Tiggemann, Marika

    2014-09-01

    With little actual appraisal, a more 'appearance potent' (i.e., a reverence for appearance ideals) subculture has been used to explain gay men's greater body dissatisfaction in comparison to straight men's. This study sought to assess the respective appearance potency of each subculture by a content analysis of 32 issues of the most read gay (Attitude, Gay Times) and straight men's magazines (Men's Health, FHM) in the UK. Images of men and women were coded for their physical characteristics, objectification and nudity, as were the number of appearance adverts and articles. The gay men's magazines featured more images of men that were appearance ideal, nude and sexualized than the straight men's magazines. The converse was true for the images of women and appearance adverts. Although more research is needed to understand the effect of this content on the viewer, the findings are consistent with a more appearance potent gay male subculture.

  11. Symplocamide A, a potent cytotoxin and chymotrypsin inhibitor from the marine Cyanobacterium Symploca sp.

    Science.gov (United States)

    Linington, Roger G; Edwards, Daniel J; Shuman, Cynthia F; McPhail, Kerry L; Matainaho, Teatulohi; Gerwick, William H

    2008-01-01

    Investigation of a Symploca sp. from Papua New Guinea has led to the isolation of symplocamide A (1), a potent cancer cell cytotoxin, which also inhibits serine proteases with a 200-fold greater inhibition of chymotrypsin over trypsin. The complete stereostructure of symplocamide A was determined by detailed NMR and MS analysis as well as chiral HPLC analysis of the component amino acid residues. The presence of several unusual structural features in symplocamide A provides new insights into the pharmacophore model for protease selectivity in this drug class and may underlie the potent cytotoxicity of this compound to H-460 lung cancer cells (IC50=40 nM) as well as neuro-2a neuroblastoma cells (IC50=29 nM).

  12. Structural basis of potent Zika-dengue virus antibody cross-neutralization.

    Science.gov (United States)

    Barba-Spaeth, Giovanna; Dejnirattisai, Wanwisa; Rouvinski, Alexander; Vaney, Marie-Christine; Medits, Iris; Sharma, Arvind; Simon-Lorière, Etienne; Sakuntabhai, Anavaj; Cao-Lormeau, Van-Mai; Haouz, Ahmed; England, Patrick; Stiasny, Karin; Mongkolsapaya, Juthathip; Heinz, Franz X; Screaton, Gavin R; Rey, Félix A

    2016-08-01

    Zika virus is a member of the Flavivirus genus that had not been associated with severe disease in humans until the recent outbreaks, when it was linked to microcephaly in newborns in Brazil and to Guillain-Barré syndrome in adults in French Polynesia. Zika virus is related to dengue virus, and here we report that a subset of antibodies targeting a conformational epitope isolated from patients with dengue virus also potently neutralize Zika virus. The crystal structure of two of these antibodies in complex with the envelope protein of Zika virus reveals the details of a conserved epitope, which is also the site of interaction of the envelope protein dimer with the precursor membrane (prM) protein during virus maturation. Comparison of the Zika and dengue virus immunocomplexes provides a lead for rational, epitope-focused design of a universal vaccine capable of eliciting potent cross-neutralizing antibodies to protect simultaneously against both Zika and dengue virus infections.

  13. Discovery of adamantyl heterocyclic ketones as potent 11β-hydroxysteroid dehydrogenase type 1 inhibitors.

    Science.gov (United States)

    Su, Xiangdong; Vicker, Nigel; Thomas, Mark P; Pradaux-Caggiano, Fabienne; Halem, Heather; Culler, Michael D; Potter, Barry V L

    2011-08-01

    11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) plays a key role in converting intracellular cortisone to physiologically active cortisol, which is implicated in the development of several phenotypes of metabolic syndrome. Inhibition of 11β-HSD1 activity with selective inhibitors has beneficial effects on various conditions, including diabetes, dyslipidemia and obesity, and therefore constitutes a promising strategy to discover novel therapies for metabolic and cardiovascular diseases. A series of novel adamantyl heterocyclic ketones provides potent and selective inhibitors of human 11β-HSD1. Lead compounds display low nanomolar inhibition against human and mouse 11β-HSD1 and are selective with no activity against 11β-HSD2 and 17β-HSD1. Selected potent 11β-HSD1 inhibitors show moderate metabolic stability upon incubation with human liver microsomes and weak inhibition of human CYP450 enzymes.

  14. Discovery of Adamantyl Heterocyclic Ketones as Potent 11β-Hydroxysteroid Dehydrogenase Type 1 Inhibitors

    Science.gov (United States)

    Su, Xiangdong; Vicker, Nigel; Thomas, Mark P; Pradaux-Caggiano, Fabienne; Halem, Heather; Culler, Michael D; Potter, Barry V L

    2011-01-01

    11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) plays a key role in converting intracellular cortisone to physiologically active cortisol, which is implicated in the development of several phenotypes of metabolic syndrome. Inhibition of 11β-HSD1 activity with selective inhibitors has beneficial effects on various conditions, including diabetes, dyslipidemia and obesity, and therefore constitutes a promising strategy to discover novel therapies for metabolic and cardiovascular diseases. A series of novel adamantyl heterocyclic ketones provides potent and selective inhibitors of human 11β-HSD1. Lead compounds display low nanomolar inhibition against human and mouse 11β-HSD1 and are selective with no activity against 11β-HSD2 and 17β-HSD1. Selected potent 11β-HSD1 inhibitors show moderate metabolic stability upon incubation with human liver microsomes and weak inhibition of human CYP450 enzymes. PMID:21608132

  15. O-(Triazolyl)methyl carbamates as a novel and potent class of FAAH inhibitors

    Science.gov (United States)

    Colombano, Giampiero; Albani, Clara; Ottonello, Giuliana; Ribeiro, Alison; Scarpelli, Rita; Tarozzo, Glauco; Daglian, Jennifer; Jung, Kwang-Mook; Piomelli, Daniele; Bandiera, Tiziano

    2015-01-01

    Inhibition of fatty acid amide hydrolase (FAAH) activity is under investigation as a valuable strategy for the treatment of several disorders, including pain and drug addiction. A number of potent FAAH inhibitors belonging to different chemical classes have been disclosed. O-aryl carbamates are one of the most representative families. In the search for novel FAAH inhibitors, we synthesized a series of O-(1,2,3-triazol-4-yl)methyl carbamate derivatives exploiting the copper-catalyzed [3 + 2] cycloaddition reaction between azides and alkynes (click chemistry). We explored structure-activity relationships within this new class of compounds and identified potent inhibitors of both rat and human FAAH with IC50 values in the single-digit nanomolar range. PMID:25338703

  16. Potent inhibitors of HCV-NS3 protease derived from boronic acids

    Energy Technology Data Exchange (ETDEWEB)

    Venkatraman, Srikanth; Wu, Wanli; Prongay, Andrew; Girijavallabhan, Viyyoor; Njoroge, F. George; (SPRI)

    2009-07-23

    Chronic hepatitis C infection is the leading causes for cirrhosis of the liver and hepatocellular carcinoma, leading to liver failure and liver transplantation. The etiological agent, HCV virus produces a single positive strand of RNA that is processed with the help of serine protease NS3 to produce mature virus. Inhibition of NS3 protease can be potentially used to develop effective drugs for HCV infections. Numerous efforts are now underway to develop potent inhibitors of HCV protease that contain ketoamides as serine traps. Herein we report the synthesis of a series of potent inhibitors that contain a boronic acid as a serine trap. The activity of these compounds were optimized to 200 pM. X-ray structure of compound 17 bound to NS3 protease is also discussed.

  17. Pyrrolo[2,3-b]pyridine derivatives as potent Bruton's tyrosine kinase inhibitors.

    Science.gov (United States)

    Zhao, Xinge; Huang, Wei; Wang, Yazhou; Xin, Minhang; Jin, Qiu; Cai, Jianfeng; Tang, Feng; Zhao, Yong; Xiang, Hua

    2015-08-01

    A series of pyrrolo[2,3-b]pyridine-based derivatives were designed as potent Bruton's tyrosine kinase (BTK) inhibitors by using a scaffold-hopping strategy. Structure-activity relationship studies identified five compounds (3n, 3p, 3q, 3r, and 3s) with IC50 of less than 10nM in BTK enzyme assay and five compounds (3m, 3n, 3o, 3p, and 3t) with IC50 of less than 20 nM in Ramos cell assay. As one of the most potent inhibitors, compound 3p exhibited superior activity to that of compound 1 (RN486) and pyrrolo[2,3-d]pyrimidine derivative 2 in both BTK enzymatic (IC50=6.0 nM) and cellular inhibition (IC50=14 nM) assays. In addition, 3p displayed favorable overall pharmacokinetic profiles compared with 1 and 2.

  18. Total Synthesis of a Highly Potent Anticancer Natural Product OSW-1

    Institute of Scientific and Technical Information of China (English)

    Zhendong Jin; Wensheng Yu

    2001-01-01

    @@ OSW-1 (1) and its four natural analogs (2-5) are five highly potent anticancer natural products that were recently isolated from the bulbs of Ornithogalum saundersiae, a perennial grown in southern Africa (Figure 1).1 The IC50 values of these compounds against human promyelocytic leukemia HL-60 cells range from between 0.1 to 0.3 nM.2 Their anticancer activities are from 10 to 100 times more potent than other well-known anticancer agents in clinical use, including mitomycin C, adriamycin, cisplatin, camptothecin, and taxol. OSW-1 (1), the main constituent of Ornithogalum saundersiae bulbs, is highly cytostatic in the NCI 60-cell in vitro screen, with a mean IC50 of 0.78 nM. It also looks promising from in vivo tests against mouse P388 leukemia (increased life span 59%) by a one-time administration of 0.01 mg/kg.

  19. Stereoselective total synthesis of the potent anti-asthmatic compound CMI-977 (LDP-977)

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Luiz Carlos; Farina, Lui Strambi; Ferreira, Marco Antonio Barbosa, E-mail: ldias@iqm.unicamp.br [Universidade de Campinas (UNICAMP), SP (Brazil). Instituto de Quimica

    2013-02-15

    A short and efficient stereoselective total synthesis of CMI-977 (LDP-977), a potent and orally active anti-asthmatic compound, was developed. The key steps involve a highly diastereoselective Mukaiyama oxidative cyclization, which provides the trans-THF (tetrahydrofuran) unit and a Seyferth-Gilbert homologation to construct the triple bond in the target molecule. The synthesis of the key chiral building block was performed using Jacobsen hydrolytic kinetic resolution. (author)

  20. Metofluthrin: a potent new synthetic pyrethroid with high vapor activity against mosquitoes.

    Science.gov (United States)

    Ujihara, Kazuya; Mori, Tatsuya; Iwasaki, Tomonori; Sugano, Masayo; Shono, Yoshinori; Matsuo, Noritada

    2004-01-01

    (1R)-trans-Norchrysanthemic acid fluorobenzyl esters are synthesized and their structure-activity relationships are discussed. These esters show outstanding insecticidal activity against mosquitoes. In particular, the 2,3,5,6-tetrafluoro-4-methoxymethylbenzyl analog (metofluthrin) exhibits the highest potency, being approximately forty times as potent as d-allethrin in a mosquito coil formulation when tested against southern house mosquitoes (Culex quinquefasciatus). Metofluthrin also exhibits a significant vapor action at room temperature.

  1. Is Globalisation A Potent Driver of Economic Growth? Investigating the Nigerian Non-Oil Exports

    OpenAIRE

    Godwin Ukaiji Okpokpo; Innocent Abanum Ifelunini; Fidelis Osuyali

    2014-01-01

    Many countries have gained from integrating into the global economy while some have not been as much fortunate. Some have come to see globalisation as a weapon for improved economic growth. With the progressive increase in the poverty level in Nigeria, there is the doubt as to whether globalisation has improved the fortune of Nigeria. More so as there have been contradictory studies on the impact of globalisation in Nigeria. This study interrogated globalisation as a potent driver of economic...

  2. Lavender Oil-Potent Anxiolytic Properties via Modulating Voltage Dependent Calcium Channels

    OpenAIRE

    2013-01-01

    Recent clinical data support the clinical use of oral lavender oil in patients suffering from subsyndromal anxiety. We identified the molecular mechanism of action that will alter the perception of lavender oil as a nonspecific ingredient of aromatherapy to a potent anxiolytic inhibiting voltage dependent calcium channels (VOCCs) as highly selective drug target. In contrast to previous publications where exorbitant high concentrations were used, the effects of lavender oil in behavioral, bioc...

  3. Potent Antioxidative Activity of Lycopene: A Potential Role in Scavenging Hypochlorous Acid †

    OpenAIRE

    Pennathur, Subramaniam; Maitra, Dhiman; Byun, Jaeman; Sliskovic, Inga; Abdulhamid, Ibrahim; Saed, Ghassan M.; DIAMOND, MICHAEL P.; Abu-Soud, Husam M.

    2010-01-01

    Lycopene, a carotenoid found in tomatoes, is a proven anti-oxidant that may lower the risk of certain disorders including heart disease and cancer. Hypochlorous acid (HOCl) is an oxidant linked to tissue oxidation in cardiovascular disease and other inflammatory disorders through its ability to modify proteins, deoxyribonucleic acid, ribonucleic acid and lipids. Here we show that lycopene can function as a potent scavenger of HOCl at a wide range of concentrations that span various pathophysi...

  4. Organotins Are Potent Activators of PPARγ and Adipocyte Differentiation in Bone Marrow Multipotent Mesenchymal Stromal Cells

    OpenAIRE

    2011-01-01

    Adipocyte differentiation in bone marrow is potentially deleterious to both bone integrity and lymphopoiesis. Here, we examine the hypothesis that organotins, common environmental contaminants that are dual ligands for peroxisome proliferator–activated receptor (PPAR) γ and its heterodimerization partner retinoid X receptor (RXR), are potent activators of bone marrow adipogenesis. A C57Bl/6-derived bone marrow multipotent mesenchymal stromal cell (MSC) line, BMS2, was treated with rosiglitazo...

  5. Remote functionalization of SCH 39166: discovery of potent and selective benzazepine dopamine D1 receptor antagonists.

    Science.gov (United States)

    Sasikumar, T K; Burnett, Duane A; Greenlee, William J; Smith, Michelle; Fawzi, Ahmad; Zhang, Hongtao; Lachowicz, Jean E

    2010-02-01

    A series of novel benzazepine derived dopamine D(1) antagonists have been discovered. These compounds are highly potent at D(1) and showed excellent selectivity over D(2) and D(4) receptors. SAR studies revealed that a variety of functional groups are tolerated on the D-ring of known tetracyclic benzazepine analog 2, SCH 39166, leading to compounds with nanomolar potency at D(1) and good selectivity over D(2)-like receptors.

  6. Saururus cernuus Lignans - Potent Small Molecule Inhibitors of Hypoxia-Inducible Factor-1

    OpenAIRE

    Hossain, Chowdhury Faiz; Kim, Yong-Pil; Baerson, Scott R; Zhang, Lei; Bruick, Richard K.; Mohammed, Kaleem A.; Agarwal, Ameeta K.; Nagle, Dale G.; Zhou, Yu-Dong

    2005-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents an important tumor-selective therapeutic target for solid tumors. In search of novel small molecule HIF-1 inhibitors, 5400 natural product-rich extracts from plants, marine organisms, and microbes were examined for HIF-1 inhibitory activities using a cell-based reporter assay. Bioassay-guided fractionation and isolation, followed by structure elucidation, yielded three potent natural product-derived HIF-1 inhibitors and two structurally related in...

  7. Studies Toward the Pharmacophore of Salvinorin A, a Potent Kappa Opioid Receptor Agonist

    OpenAIRE

    Munro, Thomas A.; Mark A. Rizzacasa; Roth, Bryan L.; Toth, Beth A.; Yan, Feng

    2005-01-01

    Salvinorin A (1), from the sage Salvia divinorum, is a potent and selective kappa opioid receptor (KOR) agonist. We screened other salvinorins and derivatives for binding affinity and functional activity at opioid receptors. Our results suggest that the methyl ester and furan ring are required for activity, but that the lactone and ketone functionalities are not. Other salvinorins showed negligible binding affinity at the KOR. None of the compounds bound to mu or delta opioid receptors.

  8. Studies toward the pharmacophore of salvinorin A, a potent kappa opioid receptor agonist.

    Science.gov (United States)

    Munro, Thomas A; Rizzacasa, Mark A; Roth, Bryan L; Toth, Beth A; Yan, Feng

    2005-01-27

    Salvinorin A (1), from the sage Salvia divinorum, is a potent and selective kappa opioid receptor (KOR) agonist. We screened other salvinorins and derivatives for binding affinity and functional activity at opioid receptors. Our results suggest that the methyl ester and furan ring are required for activity but that the lactone and ketone functionalities are not. Other salvinorins showed negligible binding affinity at the KOR. None of the compounds bound to mu or delta opioid receptors.

  9. Phenazine antibiotic inspired discovery of potent bromophenazine antibacterial agents against Staphylococcus aureus and Staphylococcus epidermidis.

    Science.gov (United States)

    Borrero, Nicholas V; Bai, Fang; Perez, Cristian; Duong, Benjamin Q; Rocca, James R; Jin, Shouguang; Huigens, Robert W

    2014-02-14

    Nearly all clinically used antibiotics have been (1) discovered from microorganisms (2) using phenotype screens to identify inhibitors of bacterial growth. The effectiveness of these antibiotics is attributed to their endogenous roles as bacterial warfare agents against competing microorganisms. Unfortunately, every class of clinically used antibiotic has been met with drug resistant bacteria. In fact, the emergence of resistant bacterial infections coupled to the dismal pipeline of new antibacterial agents has resulted in a global health care crisis. There is an urgent need for innovative antibacterial strategies and treatment options to effectively combat drug resistant bacterial pathogens. Here, we describe the implementation of a Pseudomonas competition strategy, using redox-active phenazines, to identify novel antibacterial leads against Staphylococcus aureus and Staphylococcus epidermidis. In this report, we describe the chemical synthesis and evaluation of a diverse 27-membered phenazine library. Using this microbial warfare inspired approach, we have identified several bromophenazines with potent antibacterial activities against S. aureus and S. epidermidis. The most potent bromophenazine analogue from this focused library demonstrated a minimum inhibitory concentration (MIC) of 0.78-1.56 μM, or 0.31-0.62 μg mL(-1), against S. aureus and S. epidermidis and proved to be 32- to 64-fold more potent than the phenazine antibiotic pyocyanin in head-to-head MIC experiments. In addition to the discovery of potent antibacterial agents against S. aureus and S. epidermidis, we also report a detailed structure-activity relationship for this class of bromophenazine small molecules.

  10. Isolation of azaspiracid-2 from a marine sponge Echinoclathria sp. as a potent cytotoxin.

    Science.gov (United States)

    Ueoka, Reiko; Ito, Akihiro; Izumikawa, Miho; Maeda, Satoko; Takagi, Motoki; Shin-ya, Kazuo; Yoshida, Minoru; van Soest, Rob W M; Matsunaga, Shigeki

    2009-05-01

    Azaspiracid-2 was isolated from a marine sponge Echinoclathria sp. collected off Amami-Oshima as the predominant cytotoxic constituent. A combination of HPLC using ODS, GS320, and Phenylhexyl stationary phases permitted the purification without using acid or inorganic additives in the mobile phase. Azaspiracid-2 exhibited potent cytotoxicity against P388 cells with an IC50 value of 0.72 ng/mL and caused S phase arrest on the cell cycle.

  11. Discovery of Potent and Selective Tricyclic Inhibitors of Bruton's Tyrosine Kinase with Improved Druglike Properties.

    Science.gov (United States)

    Wang, Xiaojing; Barbosa, James; Blomgren, Peter; Bremer, Meire C; Chen, Jacob; Crawford, James J; Deng, Wei; Dong, Liming; Eigenbrot, Charles; Gallion, Steve; Hau, Jonathon; Hu, Huiyong; Johnson, Adam R; Katewa, Arna; Kropf, Jeffrey E; Lee, Seung H; Liu, Lichuan; Lubach, Joseph W; Macaluso, Jen; Maciejewski, Pat; Mitchell, Scott A; Ortwine, Daniel F; DiPaolo, Julie; Reif, Karin; Scheerens, Heleen; Schmitt, Aaron; Wong, Harvey; Xiong, Jin-Ming; Xu, Jianjun; Zhao, Zhongdong; Zhou, Fusheng; Currie, Kevin S; Young, Wendy B

    2017-06-08

    In our continued effort to discover and develop best-in-class Bruton's tyrosine kinase (Btk) inhibitors for the treatment of B-cell lymphomas, rheumatoid arthritis, and systemic lupus erythematosus, we devised a series of novel tricyclic compounds that improved upon the druglike properties of our previous chemical matter. Compounds exemplified by G-744 are highly potent, selective for Btk, metabolically stable, well tolerated, and efficacious in an animal model of arthritis.

  12. A mechanism-based potent sirtuin inhibitor containing Nε-thiocarbamoyl-lysine (TuAcK)

    OpenAIRE

    2011-01-01

    In the current study, we have identified Nε-thiocarbamoyl-lysine (TuAcK) as a general sirtuin inhibitory warhead which was shown to be able to confer potent sirtuin inhibition. This inhibition was also shown to be mechanism-based in that the TuAck residue was able to be processed by a sirtuin enzyme with the formation of a stalled S-alkylamidate intermediate.

  13. Discovery of Benzisoxazoles as Potent Inhibitors of Chaperone Heat Shock Protein 90

    Energy Technology Data Exchange (ETDEWEB)

    Gopalsamy, Ariamala; Shi, Mengxiao; Golas, Jennifer; Vogan, Erik; Jacob, Jaison; Johnson, Mark; Lee, Frederick; Nilakantan, Ramaswamy; Petersen, Roseann; Svenson, Kristin; Chopra, Rajiv; Tam, May S.; Wen, Yingxia; Ellingboe, John; Arndt, Kim; Boschelli, Frank (Wyeth)

    2008-08-11

    Heat shock protein 90 (Hsp90) is a molecular chaperone that is responsible for activating many signaling proteins and is a promising target in tumor biology. We have identified small-molecule benzisoxazole derivatives as Hsp90 inhibitors. Crystallographic studies show that these compounds bind in the ATP binding pocket interacting with the Asp93. Structure based optimization led to the identification of potent analogues, such as 13, with good biochemical profiles.

  14. Fungal naphtho-γ-pyrones: Potent antibiotics for drug-resistant microbial pathogens

    OpenAIRE

    Yan He; Jun Tian; Xintao Chen; Weiguang Sun; Hucheng Zhu; Qin Li; Liang Lei; Guangmin Yao; Yongbo Xue; Jianping Wang; Hua Li; Yonghui Zhang

    2016-01-01

    Four naphtho-γ-pyrones (fonsecinones A and C and aurasperones A and E) were identified as potential antibacterial agents against Escherichia coli, extended-spectrum β-lactamase (ESBL)-producing E. coli, Pseudomonas aeruginosa, Enterococcus faecalis, and methicillin-resistant Staphylococcus aureus (MRSA) in an in vitro antibacterial screen of 218 fungal metabolites. Fonsecinone A (2) exhibited the most potent antibacterial activity, with minimum inhibitory concentrations (MICs) of 4.26, 17.04,...

  15. Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro

    OpenAIRE

    Elosta, A; Slevin, M; Rahman, K; Ahmed, N.

    2017-01-01

    Protein glycation involves formation of early (Amadori) and late advanced glycation endproducts (AGEs) together with free radicals via autoxidation of glucose and Amadori products. Glycation and increased free radical activity underlie the pathogenesis of diabetic complications. This study investigated whether aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro in a cell-free system. Proteins were glycated by incubation with sugars (g...

  16. Allyl m-Trifluoromethyldiazirine Mephobarbital: An Unusually Potent Enantioselective and Photoreactive Barbiturate General Anesthetic

    Energy Technology Data Exchange (ETDEWEB)

    Savechenkov, Pavel Y.; Zhang, Xi; Chiara, David C.; Stewart, Deirdre S.; Ge, Rile; Zhou, Xiaojuan; Raines, Douglas E.; Cohen, Jonathan B.; Forman, Stuart A.; Miller, Keith W.; Bruzik, Karol S. (Harvard-Med); (Mass. Gen. Hosp.); (UIC)

    2012-12-10

    We synthesized 5-allyl-1-methyl-5-(m-trifluoromethyl-diazirynylphenyl)barbituric acid (14), a trifluoromethyldiazirine-containing derivative of general anesthetic mephobarbital, separated the racemic mixture into enantiomers by chiral chromatography, and determined the configuration of the (+)-enantiomer as S by X-ray crystallography. Additionally, we obtained the {sup 3}H-labeled ligand with high specific radioactivity. R-(-)-14 is an order of magnitude more potent than the most potent clinically used barbiturate, thiopental, and its general anesthetic EC{sub 50} approaches those for propofol and etomidate, whereas S-(+)-14 is 10-fold less potent. Furthermore, at concentrations close to its anesthetic potency, R-(-)-14 both potentiated GABA-induced currents and increased the affinity for the agonist muscimol in human {alpha}1{beta}2/3{gamma}2L GABA{sub A} receptors. Finally, R-(-)-14 was found to be an exceptionally efficient photolabeling reagent, incorporating into both {alpha}1 and {beta}3 subunits of human {alpha}1{beta}3 GABAA receptors. These results indicate R-(-)-14 is a functional general anesthetic that is well-suited for identifying barbiturate binding sites on Cys-loop receptors.

  17. Cucurbitacins-type triterpene with potent activity on mouse embryonic fibroblast from Cucumis prophetarum, cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Seif-Eldin N Ayyad

    2011-01-01

    Full Text Available Background: Higher plants are considered as a well-known source of the potent anticancer metabolites with diversity of chemical structures. For instance, taxol is an amazing diterpene alkaloid had been lunched since 1990. Objective: To isolate the major compounds from the fruit extract of Cucumis prophetarum, Cucurbitaceae, which are mainly responsible for the bioactivities as anticancer. Materials and Methods: Plant material was shady air dried, extracted with equal volume of chloroform/methanol, and fractionated with different adsorbents. The structures of obtained pure compounds were elucidated with different spectroscopic techniques employing 1D ( 1 H and 13 C and 2D (COSY, HMQC and HMBC NMR (Nuclear Magnetic Resonance Spectrometry and ESI-MS (Eelectrospray Ionization Mass Spectrometry spectroscopy. The pure isolates were tested towards human cancer cell lines, mouse embryonic fibroblast (NIH3T3 and virally transformed form (KA3IT. Results: Two cucurbitacins derivatives, dihydocucurbitacin B (1 and cucurbitacin B (2, had been obtained. Compounds 1 and 2 showed potent inhibitory activities toward NIH3T3 and KA31T with IC 50 0.2, 0.15, 2.5 and 2.0 μg/ml, respectively. Conclusion: The naturally cucurbitacin derivatives (dihydocucurbitacin B and cucurbitacin B showed potent activities towards NIH3T3 and KA31T, could be considered as a lead of discovering a new anticancer natural drug.

  18. Synthesis of organic nitrates of luteolin as a novel class of potent aldose reductase inhibitors.

    Science.gov (United States)

    Wang, Qi-Qin; Cheng, Ning; Zheng, Xiao-Wei; Peng, Sheng-Ming; Zou, Xiao-Qing

    2013-07-15

    Aldose reductase (AR) plays an important role in the design of drugs that prevent and treat diabetic complications. Aldose reductase inhibitors (ARIs) have received significant attentions as potent therapeutic drugs. Based on combination principles, three series of luteolin derivatives were synthesised and evaluated for their AR inhibitory activity and nitric oxide (NO)-releasing capacity in vitro. Eighteen compounds were found to be potent ARIs with IC50 values ranging from (0.099±0.008) μM to (2.833±0.102) μM. O(7)-Nitrooxyethyl-O(3'),O(4')-ethylidene luteolin (La1) showed the most potent AR inhibitory activity [IC50=(0.099±0.008) μM]. All organic nitrate derivatives released low concentrations of NO in the presence of l-cysteine. Structure-activity relationship studies suggested that introduction of an NO donor, protection of the catechol structure, and the ether chain of a 2-carbon spacer as a coupling chain on the luteolin scaffold all help increase the AR inhibitory activity of the resulting compound. This class of NO-donor luteolin derivatives as efficient ARIs offer a new concept for the development and design of new drug for preventive and therapeutic drugs for diabetic complications.

  19. Total synthesis and biological evaluation of pederin, psymberin, and highly potent analogs.

    Science.gov (United States)

    Wan, Shuangyi; Wu, Fanghui; Rech, Jason C; Green, Michael E; Balachandran, Raghavan; Horne, W Seth; Day, Billy W; Floreancig, Paul E

    2011-10-19

    The potent cytotoxins pederin and psymberin have been prepared through concise synthetic routes (10 and 14 steps in the longest linear sequences, respectively) that proceed via a late-stage multicomponent approach to construct the N-acyl aminal linkages. This route allowed for the facile preparation of a number of analogs that were designed to explore the importance of the alkoxy group in the N-acyl aminal and functional groups in the two major subunits on biological activity. These analogs, including a pederin/psymberin chimera, were analyzed for their growth inhibitory effects, revealing several new potent cytotoxins and leading to postulates regarding the molecular conformational and hydrogen bonding patterns that are required for biological activity. Second generation analogs have been prepared based on the results of the initial assays and a structure-based model for the binding of these compounds to the ribosome. The growth inhibitory properties of these compounds are reported. These studies show the profound role that organic chemistry in general and specifically late-stage multicomponent reactions can play in the development of unique and potent effectors for biological responses.

  20. Pyrazolo Derivatives as Potent Adenosine Receptor Antagonists: An Overview on the Structure-Activity Relationships

    Directory of Open Access Journals (Sweden)

    Siew Lee Cheong

    2011-01-01

    Full Text Available In the past few decades, medicinal chemistry research towards potent and selective antagonists of human adenosine receptors (namely, A1, A2A, A2B, and A3 has been evolving rapidly. These antagonists are deemed therapeutically beneficial in several pathological conditions including neurological and renal disorders, cancer, inflammation, and glaucoma. Up to this point, many classes of compounds have been successfully synthesized and identified as potent human adenosine receptor antagonists. In this paper, an overview of the structure-activity relationship (SAR profiles of promising nonxanthine pyrazolo derivatives is reported and discussed. We have emphasized the SAR for some representative structures such as pyrazolo-[4,3-e]-1,2,4-triazolo-[1,5-c]pyrimidines; pyrazolo-[3,4-c] or -[4,3-c]quinolines; pyrazolo-[4,3-d]pyrimidinones; pyrazolo-[3,4-d]pyrimidines and pyrazolo-[1,5-a]pyridines. This overview not only clarifies the structural requirements deemed essential for affinity towards individual adenosine receptor subtypes, but it also sheds light on the rational design and optimization of existing structural templates to allow us to conceive new, more potent adenosine receptor antagonists.

  1. Potential antipsoriatic agents: lapacho compounds as potent inhibitors of HaCaT cell growth.

    Science.gov (United States)

    Müller, K; Sellmer, A; Wiegrebe, W

    1999-08-01

    A number of lapacho compounds, representing the most common constituents of the inner bark of Tabebuia impetiginosa, together with some synthetic analogues, were evaluated in vitro against the growth of the human keratinocyte cell line HaCaT. With an IC(50) value of 0.7 microM, beta-lapachone (4) displayed activity comparable to that of the antipsoriatic drug anthralin. 2-Acetyl-8-hydroxynaphtho[2,3-b]furan-4,9-dione (7), which was prepared in a four-step synthesis from 2,8-dihydroxy-1, 4-naphthoquinone, was the most potent inhibitor among the known lapacho-derived compounds and inhibited cell growth with an IC(50) value of 0.35 microM. Furthermore, other active constituents of lapacho inhibited keratinocyte growth, with IC(50) values in the range of 0.5-3.0 microM. However, as already observed with anthralin, treatment of HaCaT cells with these potent lapacho compounds also caused remarkable damage to the plasma membrane. This was documented by leakage of lactate dehydrogenase into the culture medium, which significantly exceeded that of the vehicle control. Because of their potent activity against the growth of human keratinocytes, some lapacho-derived compounds appear to be promising as effective antipsoriatic agents.

  2. Potent antimicrobial small molecules screened as inhibitors of tyrosine recombinases and Holliday junction-resolving enzymes.

    Science.gov (United States)

    Rideout, Marc C; Boldt, Jeffrey L; Vahi-Ferguson, Gabriel; Salamon, Peter; Nefzi, Adel; Ostresh, John M; Giulianotti, Marc; Pinilla, Clemencia; Segall, Anca M

    2011-11-01

    Holliday junctions (HJs) are critical intermediates in many recombination-dependent DNA repair pathways. Our lab has previously identified several hexameric peptides that target HJ intermediates formed in DNA recombination reactions. One of the most potent peptides, WRWYCR, is active as a homodimer and has shown bactericidal activity partly because of its ability to interfere with DNA repair proteins that act upon HJs. To increase the possibility of developing a therapeutic targeting DNA repair, we searched for small molecule inhibitors that were functional surrogates of the peptides. Initial screens of heterocyclic small molecule libraries resulted in the identification of several N-methyl aminocyclic thiourea inhibitors. Like the peptides, these inhibitors trapped HJs formed during recombination reactions in vitro, but were less potent than the peptides in biochemical assays and had little antibacterial activity. In this study, we describe the screening of a second set of libraries containing somewhat larger and more symmetrical scaffolds in an effort to mimic the symmetry of a WRWYCR homodimer and its target. From this screen, we identified several pyrrolidine bis-cyclic guanidine inhibitors that also interfere with processing of HJs in vitro and are potent inhibitors of Gram-negative and especially Gram-positive bacterial growth. These molecules are proof-of-principle of a class of compounds with novel activities, which may in the future be developed into a new class of antibiotics that will expand the available choices for therapy against drug-resistant bacteria.

  3. Conformation-Dependent High-Affinity Potent Ricin-Neutralizing Monoclonal Antibodies

    Directory of Open Access Journals (Sweden)

    Wei-Gang Hu

    2013-01-01

    Full Text Available Ricin is a potential biothreat agent with no approved antidote available for ricin poisoning. The aim of this study was to develop potent antibody-based antiricin antidotes. Four strong ricin resistant hybridoma clones secreting antiricin monoclonal antibodies (mAbs were developed. All four mAbs are bound to conformational epitopes of ricin toxin B (RTB with high affinity (KD values from 2.55 to 36.27 nM. RTB not only triggers cellular uptake of ricin, but also facilitates transport of the ricin toxin A (RTA from the endoplasmic reticulum to the cytosol, where RTA exerts its toxic activity. The four mAbs were found to have potent ricin-neutralizing capacities and synergistic effects among them as determined by an in vitro neutralization assay. In vivo protection assay demonstrated that all four mAbs had strong efficacy against ricin challenges. D9 was found to be exceptionally effective. Intraperitoneal (i.p. administration of D9, at a dose of 5 μg, 6 weeks before or 6 hours after an i.p. challenge with 5 × LD50 of ricin was able to protect or rescue 100% of the mice, indicating that mAb D9 is an excellent candidate to be developed as a potent antidote against ricin poisoning for both prophylactic and therapeutic purposes.

  4. MIT(1), a black mamba toxin with a new and highly potent activity on intestinal contraction.

    Science.gov (United States)

    Schweitz, H; Pacaud, P; Diochot, S; Moinier, D; Lazdunski, M

    1999-11-19

    Mamba intestinal toxin (MIT(1)) isolated from Dendroaspis polylepis venom is a 81 amino acid polypeptide cross-linked by five disulphide bridges. MIT(1) has a very potent action on guinea-pig intestinal contractility. MIT(1) (1 nM) potently contracts longitudinal ileal muscle and distal colon, and this contraction is equivalent to that of 40 mM K(+). Conversely MIT(1) relaxes proximal colon again as potently as 40 mM K(+). The MIT(1)-induced effects are antagonised by tetrodotoxin (1 microM) in proximal and distal colon but not in longitudinal ileum. The MIT(1)-induced relaxation of the proximal colon is reversibly inhibited by the NO synthase inhibitor L-NAME (200 microM). (125)I-labelled MIT(1) binds with a very high affinity to both ileum and brain membranes (K(d)=1.3 pM and 0.9 pM, and B(max)=30 fmol/mg and 26 fmol/mg, respectively). MIT(1) is a very highly selective toxin for a receptor present both in the CNS and in the smooth muscle and which might be an as yet unidentified K(+) channel.

  5. Novel iodoacetamido benzoheterocyclic derivatives with potent antileukemic activity are inhibitors of STAT5 phosphorylation

    Science.gov (United States)

    Romagnoli, Romeo; Baraldi, Pier Giovanni; Prencipe, Filippo; Lopez-Cara, Carlota; Rondanin, Riccardo; Simoni, Daniele; Hamel, Ernest; Grimaudo, Stefania; Pipitone, Rosaria Maria; Meli, Maria; Tolomeo, Manlio

    2015-01-01

    Signal Transducer and Activator of Transcription 5 (STAT5) protein, a component of the STAT family of signaling proteins, is considered to be an attractive therapeutic target because of its involvement in the progression of acute myeloid leukemia. In an effort to discover potent molecules able to inhibit the phosphorylation-activation of STAT5, twenty-two compounds were synthesized and evaluated on the basis of our knowledge of the activity of 2-(3′,4′,5′-trimethoxybenzoyl)-3-iodoacetamido-6-methoxybenzo[b]furan derivative 1 as a potent STAT5 inhibitor. Most of these molecules, structurally related to compound 1, were characterized by the presence of a common 3′,4′,5′-trimethoxybenzoyl moiety at the 2-position of different benzoheterocycles such as benzo[b]furan, benzo[b]thiophene, indole and N-methylindole. Effects on biological activity of the iodoacetamido group and of different moieties (methyl and methoxy) at the C-3 to C-7 positions were examined. In the series of benzo[b]furan derivatives, moving the iodoacetylamino group from the C-4 to the C-5 or C-6 positions did not significantly affect antiproliferative activity. Compounds 4, 15, 20 and 23 blocked STAT5 signals and induced apoptosis of K562 BCR–ABL positive cells. For compound 23, the trimethoxybenzoyl moiety at the 2-position of the benzo[b]furan core was not essential for potent inhibition of STAT5 activation. PMID:26629859

  6. From the potent and selective mu opioid receptor agonist H-Dmt-d-Arg-Phe-Lys-NH(2) to the potent delta antagonist H-Dmt-Tic-Phe-Lys(Z)-OH.

    Science.gov (United States)

    Balboni, Gianfranco; Cocco, Maria Teresa; Salvadori, Severo; Romagnoli, Romeo; Sasaki, Yusuke; Okada, Yoshio; Bryant, Sharon D; Jinsmaa, Yunden; Lazarus, Lawrence H

    2005-08-25

    H-Dmt-d-Arg-Phe-Lys-NH(2) ([Dmt(1)]DALDA) binds with high affinity and selectivity to the mu opioid receptor and is a potent and long-acting analgesic. Substitution of d-Arg in position 2 with Tic and masking of the lysine amine side chain by Z protection and of the C-terminal carboxylic function instead of the amide function transform a potent and selective mu agonist into a potent and selective delta antagonist H-Dmt-Tic-Phe-Lys(Z)-OH. Such a delta antagonist could be used as a pharmacological tool.

  7. Safe interruption of maintenance therapy against previous infection with four common HIV-associated opportunistic pathogens during potent antiretroviral therapy

    DEFF Research Database (Denmark)

    Kirk, Ole; Reiss, Peter; Uberti-Foppa, Caterina;

    2002-01-01

    BACKGROUND: The safety of interrupting maintenance therapy for previous opportunistic infections other than Pneumocystis carinii pneumonia among patients with HIV infection who respond to potent antiretroviral therapy has not been well documented. OBJECTIVE: To assess the safety of interrupting m...

  8. GBR-12909 and fluspirilene potently inhibited binding of ( sup 3 H) (+) 3-PPP to sigma receptors in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, P.C.; Bremer, M.E.; Rao, T.S. (G. D. Searle Co., Chesterfield, MO (USA))

    1990-01-01

    Fluspirilene and GBR-12909, two compounds structurally similar to BMY-14802 and haloperidol, were assessed for their ability to interact with sigma receptors. Fluspirilene, an antipsychotic agent that interacts potently with dopamine receptors, inhibited the binding of ({sup 3}H)-(+)3-PPP (IC{sub 50} = 380 nM) more potently than rimcazole, a putative sigma antagonist that was tested clinically for antipsychotic activity. GBR-12909, a potent dopamine uptake blocker, also inhibited the binding of ({sup 3}H)-(+)3-PPP with an IC{sub 50} of 48 nM. However, other compounds that block the re-uptake of catecholamines, such as nomifensine, desipramine, imipramine, xylamine, benztropine and cocaine, were much weaker than GBR-12909as sigma ligands. Thus, GBR-12909 and fluspirilene, compounds structurally similar to BMY-14802, are potent sigma ligands.

  9. Safe interruption of maintenance therapy against previous infection with four common HIV-associated opportunistic pathogens during potent antiretroviral therapy

    DEFF Research Database (Denmark)

    Kirk, Ole; Reiss, Peter; Uberti-Foppa, Caterina

    2002-01-01

    BACKGROUND: The safety of interrupting maintenance therapy for previous opportunistic infections other than Pneumocystis carinii pneumonia among patients with HIV infection who respond to potent antiretroviral therapy has not been well documented. OBJECTIVE: To assess the safety of interrupting m...

  10. Biaryl ethers as potent allosteric inhibitors of reverse transcriptase and its key mutant viruses: aryl substituted pyrazole as a surrogate for the pyrazolopyridine motif.

    Science.gov (United States)

    Su, Dai-Shi; Lim, John J; Tinney, Elizabeth; Tucker, Thomas J; Saggar, Sandeep; Sisko, John T; Wan, Bang-Lin; Young, Mary Beth; Anderson, Kenneth D; Rudd, Deanne; Munshi, Vandna; Bahnck, Carolyn; Felock, Peter J; Lu, Meiquing; Lai, Ming-Tain; Touch, Sinoeun; Moyer, Gregory; Distefano, Daniel J; Flynn, Jessica A; Liang, Yuexia; Sanchez, Rosa; Perlow-Poehnelt, Rebecca; Miller, Mike; Vacca, Joe P; Williams, Theresa M; Anthony, Neville J

    2010-08-01

    Biaryl ethers were recently reported as potent NNRTIs. Herein, we disclose a detailed effort to modify the previously reported compound 1. We have designed and synthesized a series of novel pyrazole derivatives as a surrogate for pyrazolopyridine motif that were potent inhibitors of HIV-1 RT with nanomolar intrinsic activity on the WT and key mutant enzymes and potent antiviral activity in infected cells.

  11. CR8, a potent and selective, roscovitine-derived inhibitor of cyclin-dependent kinases.

    Science.gov (United States)

    Bettayeb, K; Oumata, N; Echalier, A; Ferandin, Y; Endicott, J A; Galons, H; Meijer, L

    2008-10-02

    Among the ten pharmacological inhibitors of cyclin-dependent kinases (CDKs) currently in clinical trials, the purine roscovitine (CYC202, Seliciclib) is undergoing phase 2 trials against non-small-cell lung and nasopharyngeal cancers. An extensive medicinal chemistry study, designed to generate more potent analogues of roscovitine, led to the identification of an optimal substitution at the N6 position (compound CR8). An extensive selectivity study (108 kinases) highlights the exquisite selectivity of CR8 for CDK1/2/3/5/7/9. CR8 was 2- to 4-fold more potent than (R)-roscovitine at inhibiting these kinases. Cocrystal structures of (R)-CR8 and (R)-roscovitine with pCDK2/cyclin A showed that both inhibitors adopt essentially identical positions. The cellular effects of CR8 and (R)-roscovitine were investigated in human neuroblastoma SH-SY5Y cells. CR8 inhibited the phosphorylation of CDK1 and 9 substrates, with a 25-50 times higher potency compared to (R)-roscovitine. CR8 was consistently more potent than (R)-roscovitine at inducing apoptotic cell death parameters: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium reduction (40-fold), lactate dehydrogenase release (35-fold), caspases activation (68-fold) and poly-(ADP-ribose)polymerase cleavage (50-fold). This improved cell death-inducing activity of CR8 over (R)-roscovitine was observed in 25 different cell lines. Altogether these results show that second-generation analogues of (R)-roscovitine can be designed with improved antitumor potential.

  12. Masitinib (AB1010, a potent and selective tyrosine kinase inhibitor targeting KIT.

    Directory of Open Access Journals (Sweden)

    Patrice Dubreuil

    Full Text Available BACKGROUND: The stem cell factor receptor, KIT, is a target for the treatment of cancer, mastocytosis, and inflammatory diseases. Here, we characterise the in vitro and in vivo profiles of masitinib (AB1010, a novel phenylaminothiazole-type tyrosine kinase inhibitor that targets KIT. METHODOLOGY/PRINCIPAL FINDINGS: In vitro, masitinib had greater activity and selectivity against KIT than imatinib, inhibiting recombinant human wild-type KIT with an half inhibitory concentration (IC(50 of 200+/-40 nM and blocking stem cell factor-induced proliferation and KIT tyrosine phosphorylation with an IC(50 of 150+/-80 nM in Ba/F3 cells expressing human or mouse wild-type KIT. Masitinib also potently inhibited recombinant PDGFR and the intracellular kinase Lyn, and to a lesser extent, fibroblast growth factor receptor 3. In contrast, masitinib demonstrated weak inhibition of ABL and c-Fms and was inactive against a variety of other tyrosine and serine/threonine kinases. This highly selective nature of masitinib suggests that it will exhibit a better safety profile than other tyrosine kinase inhibitors; indeed, masitinib-induced cardiotoxicity or genotoxicity has not been observed in animal studies. Molecular modelling and kinetic analysis suggest a different mode of binding than imatinib, and masitinib more strongly inhibited degranulation, cytokine production, and bone marrow mast cell migration than imatinib. Furthermore, masitinib potently inhibited human and murine KIT with activating mutations in the juxtamembrane domain. In vivo, masitinib blocked tumour growth in mice with subcutaneous grafts of Ba/F3 cells expressing a juxtamembrane KIT mutant. CONCLUSIONS: Masitinib is a potent and selective tyrosine kinase inhibitor targeting KIT that is active, orally bioavailable in vivo, and has low toxicity.

  13. UV-inactivated HSV-1 potently activates NK cell killing of leukemic cells.

    Science.gov (United States)

    Samudio, Ismael; Rezvani, Katayoun; Shaim, Hila; Hofs, Elyse; Ngom, Mor; Bu, Luke; Liu, Guoyu; Lee, Jason T C; Imren, Suzan; Lam, Vivian; Poon, Grace F T; Ghaedi, Maryam; Takei, Fumio; Humphries, Keith; Jia, William; Krystal, Gerald

    2016-05-26

    Herein we demonstrate that oncolytic herpes simplex virus-1 (HSV-1) potently activates human peripheral blood mononuclear cells (PBMCs) to lyse leukemic cell lines and primary acute myeloid leukemia samples, but not healthy allogeneic lymphocytes. Intriguingly, we found that UV light-inactivated HSV-1 (UV-HSV-1) is equally effective in promoting PBMC cytolysis of leukemic cells and is 1000- to 10 000-fold more potent at stimulating innate antileukemic responses than UV-inactivated cytomegalovirus, vesicular stomatitis virus, reovirus, or adenovirus. Mechanistically, UV-HSV-1 stimulates PBMC cytolysis of leukemic cells, partly via Toll-like receptor-2/protein kinase C/nuclear factor-κB signaling, and potently stimulates expression of CD69, degranulation, migration, and cytokine production in natural killer (NK) cells, suggesting that surface components of UV-HSV-1 directly activate NK cells. Importantly, UV-HSV-1 synergizes with interleukin-15 (IL-15) and IL-2 in inducing activation and cytolytic activity of NK cells. Additionally, UV-HSV-1 stimulates glycolysis and fatty acid oxidation-dependent oxygen consumption in NK cells, but only glycolysis is required for their enhanced antileukemic activity. Last, we demonstrate that T cell-depleted human PBMCs exposed to UV-HSV-1 provide a survival benefit in a murine xenograft model of human acute myeloid leukemia (AML). Taken together, our results support the preclinical development of UV-HSV-1 as an adjuvant, alone or in combination with IL-15, for allogeneic donor mononuclear cell infusions to treat AML.

  14. Discovery of a Selective Inhibitor of Oncogenic B-Raf Kinase With Potent Antimelanoma Activity

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, J.; Lee, J.T.; Wang, W.; Zhang, J.; Cho, H.; Mamo, S.; Bremer, R.; Gillette, S.; Kong, J.; Haass, N.K.; Sproesser, K.; Li, L.; Smalley, K.S.M.; Fong, D.; Zhu, Y.-L.; Marimuthu, A.; Nguyen, H.; Lam, B.; Liu, J.; Cheung, I.; Rice, J.

    2009-05-26

    BRAF{sup V600E} is the most frequent oncogenic protein kinase mutation known. Furthermore, inhibitors targeting 'active' protein kinases have demonstrated significant utility in the therapeutic repertoire against cancer. Therefore, we pursued the development of specific kinase inhibitors targeting B-Raf, and the V600E allele in particular. By using a structure-guided discovery approach, a potent and selective inhibitor of active B-Raf has been discovered. PLX4720, a 7-azaindole derivative that inhibits B-Raf{sup V600E} with an IC{sub 50} of 13 nM, defines a class of kinase inhibitor with marked selectivity in both biochemical and cellular assays. PLX4720 preferentially inhibits the active B-Raf{sup V600E} kinase compared with a broad spectrum of other kinases, and potent cytotoxic effects are also exclusive to cells bearing the V600E allele. Consistent with the high degree of selectivity, ERK phosphorylation is potently inhibited by PLX4720 in B-Raf{sup V600E}-bearing tumor cell lines but not in cells lacking oncogenic B-Raf. In melanoma models, PLX4720 induces cell cycle arrest and apoptosis exclusively in B-Raf{sup V600E}-positive cells. In B-Raf{sup V600E}-dependent tumor xenograft models, orally dosed PLX4720 causes significant tumor growth delays, including tumor regressions, without evidence of toxicity. The work described here represents the entire discovery process, from initial identification through structural and biological studies in animal models to a promising therapeutic for testing in cancer patients bearing B-Raf{sup V600E}-driven tumors.

  15. Cloning and Characterization of Two Potent Kunitz Type Protease Inhibitors from Echinococcus granulosus.

    Science.gov (United States)

    Ranasinghe, Shiwanthi L; Fischer, Katja; Zhang, Wenbao; Gobert, Geoffrey N; McManus, Donald P

    2015-12-01

    The tapeworm Echinococcus granulosus is responsible for cystic echinococcosis (CE), a cosmopolitan disease which imposes a significant burden on the health and economy of affected communities. Little is known about the molecular mechanisms whereby E. granulosus is able to survive in the hostile mammalian host environment, avoiding attack by host enzymes and evading immune responses, but protease inhibitors released by the parasite are likely implicated. We identified two nucleotide sequences corresponding to secreted single domain Kunitz type protease inhibitors (EgKIs) in the E. granulosus genome, and their cDNAs were cloned, bacterially expressed and purified. EgKI-1 is highly expressed in the oncosphere (egg) stage and is a potent chymotrypsin and neutrophil elastase inhibitor that binds calcium and reduced neutrophil infiltration in a local inflammation model. EgKI-2 is highly expressed in adult worms and is a potent inhibitor of trypsin. As powerful inhibitors of mammalian intestinal proteases, the EgKIs may play a pivotal protective role in preventing proteolytic enzyme attack thereby ensuring survival of E. granulosus within its mammalian hosts. EgKI-1 may also be involved in the oncosphere in host immune evasion by inhibiting neutrophil elastase and cathepsin G once this stage is exposed to the mammalian blood system. In light of their key roles in protecting E. granulosus from host enzymatic attack, the EgKI proteins represent potential intervention targets to control CE. This is important as new public health measures against CE are required, given the inefficiencies of available drugs and the current difficulties in its treatment and control. In addition, being a small sized highly potent serine protease inhibitor, and an inhibitor of neutrophil chemotaxis, EgKI-1 may have clinical potential as a novel anti-inflammatory therapeutic.

  16. Potent delta-opioid receptor agonists containing the Dmt-Tic pharmacophore.

    Science.gov (United States)

    Balboni, Gianfranco; Salvadori, Severo; Guerrini, Remo; Negri, Lucia; Giannini, Elisa; Jinsmaa, Yunden; Bryant, Sharon D; Lazarus, Lawrence H

    2002-12-01

    Conversion of delta-opioid receptor antagonists containing the 2',6'-dimethyl-L-tyrosine (Dmt)-1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) pharmacophore into potent delta-agonists required a third heteroaromatic nucleus, such as 1H-benzimidazole-2-yl (Bid) and a linker of specified length both located C-terminally to Tic in the general formula H-Dmt-Tic-NH-CH(R)-R'. The distance between Tic and Bid is a determining factor responsible for the acquisition of delta agonism (2, 2', 3, 4, 6) or delta antagonism (8). Compounds containing a C-terminal Ala (1, 1'), Asp (5), or Asn (7) with an amide (1, 1', 5) or free acid group (7) served as delta-antagonist controls lacking the third heteroaromatic ring. A change in chirality of the spacer (2, 2') or inclusion of a negative charge via derivatives of Asp (4, 6) resulted in potent delta agonism and moderate mu agonism, although delta-receptor affinity decreased about 10-fold for 4 while mu affinity fell by over 2 orders of magnitude. Repositioning of the negative charge in the linker altered activity: H-Dmt-Tic-NH-CH(CH(2)-Bid)COOH (6) maintained high delta affinity (K(i) = 0.042 nM) and delta agonism (IC(50) = 0.015 nM), but attachment of the free acid group to Bid [H-Dmt-Tic-NH-CH(2)-Bid(CH(2)-COOH) (9)] reconstituted delta antagonism (K(e) = 0.27 nM). The data demonstrate that a linker separating the Dmt-Tic pharmacophore and Bid, regardless of the presence of a negative charge, is important in the acquisition of opioids exhibiting potent delta agonism and weak mu agonism from a parent delta antagonist.

  17. Cation hexaammines are selective and potent inhibitors of the CorA magnesium transport system.

    Science.gov (United States)

    Kucharski, L M; Lubbe, W J; Maguire, M E

    2000-06-02

    Cation hexaammines and related compounds are chemically stable analogs of the hydrated form of cations, particularly Mg(2+). We tested the ability of several of these compounds to inhibit transport by the CorA or MgtB Mg(2+) transport systems or the PhoQ receptor kinase for Mg(2+) in Salmonella typhimurium. Cobalt(III)-, ruthenium(II)-, and ruthenium(III)-hexaammines were potent inhibitors of CorA-mediated influx. Cobalt(III)- and ruthenium(III)chloropentaammines were slightly less potent inhibitors of CorA. The compounds inhibited uptake by the bacterial S. typhimurium CorA and by the archaeal Methanococcus jannaschii CorA, which bear only 12% identity in the extracellular periplasmic domain. Cation hexaammines also inhibited growth of S. typhimurium strains dependent on CorA for Mg(2+) uptake but not of isogenic strains carrying a second Mg(2+) uptake system. In contrast, hexacyano-cobaltate(III) and ruthenate(II)- and nickel(II)hexaammine had little effect on uptake. The inhibition by the cation hexaammines was selective for CorA because none of the compounds had any effect on transport by the MgtB P-type ATPase Mg(2+) transporter or the PhoQ Mg(2+) receptor kinase. These results demonstrate that cation hexaammines are potent and highly selective inhibitors of the CorA Mg(2+) transport system and further indicate that the initial interaction of the CorA transporter is with a fully hydrated Mg(2+) cation.

  18. Tremorgenic indole alkaloids potently inhibit smooth muscle high-conductance calcium-activated potassium channels.

    Science.gov (United States)

    Knaus, H G; McManus, O B; Lee, S H; Schmalhofer, W A; Garcia-Calvo, M; Helms, L M; Sanchez, M; Giangiacomo, K; Reuben, J P; Smith, A B

    1994-05-17

    Tremorgenic indole alkaloids produce neurological disorders (e.g., staggers syndromes) in ruminants. The mode of action of these fungal mycotoxins is not understood but may be related to their known effects on neurotransmitter release. To determine whether these effects could be due to inhibition of K+ channels, the interaction of various indole diterpenes with high-conductance Ca(2+)-activated K+ (maxi-K) channels was examined. Paspalitrem A, paspalitrem C, aflatrem, penitrem A, and paspalinine inhibit binding of [125I]charybdotoxin (ChTX) to maxi-K channels in bovine aortic smooth muscle sarcolemmal membranes. In contrast, three structurally related compounds, paxilline, verruculogen, and paspalicine, enhanced toxin binding. As predicted from the binding studies, covalent incorporation of [125I]ChTX into the 31-kDa subunit of the maxi-K channel was blocked by compounds that inhibit [125I]ChTX binding and enhanced by compounds that stimulate [125I]ChTX binding. Modulation of [125I]ChTX binding was due to allosteric mechanisms. Despite their different effects on binding of [125I]ChTX to maxi-K channels, all compounds potently inhibited maxi-K channels in electrophysiological experiments. Other types of voltage-dependent or Ca(2+)-activated K+ channels examined were not affected. Chemical modifications of paxilline indicate a defined structure-activity relationship for channel inhibition. Paspalicine, a deshydroxy analog of paspalinine lacking tremorgenic activity, also potently blocked maxi-K channels. Taken together, these data suggest that indole diterpenes are the most potent nonpeptidyl inhibitors of maxi-K channels identified to date. Some of their pharmacological properties could be explained by inhibition of maxi-K channels, although tremorgenicity may be unrelated to channel block.

  19. A multifunctional drug combination shows highly potent therapeutic efficacy against human cancer xenografts in athymic mice.

    Directory of Open Access Journals (Sweden)

    Xiu-Jun Liu

    Full Text Available The tumor microenvironment plays a crucial role during tumor development. Integrated combination of drugs that target tumor microenvironment is a promising approach to anticancer therapy. Here, we report a multifunctional combination of low-cytotoxic drugs composed of dipyridamole, bestatin and dexamethasone (DBDx which mainly acts on the tumor microenvironment shows highly potent antitumor efficacy in vivo. In mouse hepatoma H22 model, the triple drug combination showed synergistic and highly potent antitumor efficacy. The combination indices of various combinations of the triple drugs were between 0.2 and 0.5. DBDx inhibited the growth of a panel of human tumor xenografts and showed no obvious systemic toxicity. At tolerated doses, DBDx suppressed the growth of human hepatocellular carcinoma BEL-7402, HepG2, and lung adenocarcinoma A549 xenografts by 94.5%, 93.7% and 96.9%, respectively. Clonogenic assay demonstrated that DBDx showed weak cytotoxicity. Western blot showed that Flk1 and Nos3 were down-regulated in the DBDx-treated group. Proteomic analysis showed that DBDx mainly affected the metabolic process and immune system process; in addition, the angiogenesis and VEGF signaling pathway were also affected. Conclusively, DBDx, a multifunctional drug combination of three low-cytotoxic drugs, shows synergistic and highly potent antitumor efficacy evidently mediated by the modulation of tumor microenvironment. Based on its low-cytotoxic attributes and its broad-spectrum antitumor therapeutic efficacy, this multifunctional combination might be useful in the treatment of cancers, especially those refractory to conventional chemotherapeutics.

  20. 3,5-Bis(3-alkylaminomethyl-4-hydroxybenzylidene)-4-piperidones: A Novel Class of Potent Tumor-Selective Cytotoxins.

    Science.gov (United States)

    Karki, Subhas S; Das, Umashankar; Umemura, Naoki; Sakagami, Hiroshi; Iwamoto, Shoko; Kawase, Masami; Balzarini, Jan; De Clercq, Erik; Dimmock, Stephen G; Dimmock, Jonathan R

    2016-01-28

    Novel 4-piperidone derivatives 2a-f are disclosed as potent cytotoxins. Many of these compounds are more potent than the reference drug melphalan. The compounds in series 2, 4-7 display selective toxicities toward various neoplasms compared to some normal cells. 2a is one of the promising lead molecules that display >11-fold higher growth inhibiting potency than 5-fluorouracil against human colon cancer cells. 2a induces apoptosis, DNA fragmentation, and cleavage of poly ADP-ribose polymerase.

  1. Potent free radical scavenging activity of propol isolated from Brazilian propolis.

    Science.gov (United States)

    Basnet, P; Matsuno, T; Neidlein, R

    1997-01-01

    We evaluated free radical scavenging activity of the water, methanol and chloroform extracts of propolis in 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical and xanthine-xanthine oxidase (XOD) generated superoxide anion assay systems. The free radical scavenging activity guided fractionation and chemical analysis led to the isolation of a new compound, propol (3-[4-hydroxy-3-(3-oxo-but-1-enyl)-phenyl]-acrylic acid) from the water extract, which was more potent than most common antioxidants such as vitamin C and vitamin E (alpha-tocopherol) in these assay systems.

  2. Discovery and crystallography of bicyclic arylaminoazines as potent inhibitors of HIV-1 reverse transcriptase.

    Science.gov (United States)

    Lee, Won-Gil; Frey, Kathleen M; Gallardo-Macias, Ricardo; Spasov, Krasimir A; Chan, Albert H; Anderson, Karen S; Jorgensen, William L

    2015-11-01

    Non-nucleoside inhibitors of HIV-1 reverse transcriptase (HIV-RT) are reported that incorporate a 7-indolizinylamino or 2-naphthylamino substituent on a pyrimidine or 1,3,5-triazine core. The most potent compounds show below 10 nanomolar activity towards wild-type HIV-1 and variants bearing Tyr181Cys and Lys103Asn/Tyr181Cys resistance mutations. The compounds also feature good aqueous solubility. Crystal structures for two complexes enhance the analysis of the structure-activity data.

  3. New anabaenopeptins, potent carboxypeptidase-A inhibitors from the cyanobacterium Aphanizomenon flos-aquae.

    Science.gov (United States)

    Murakami, M; Suzuki, S; Itou, Y; Kodani, S; Ishida, K

    2000-09-01

    Anabaenopeptins I (1) and J (2), two new ureido bond-containing cyclic peptides, were isolated from the cultured cyanobacterium Aphanizomenon flos-aquae (NIES-81) as potent carboxypeptidase-A (CPA) inhibitors. The gross structures of 1 and 2 were established by spectroscopic analysis, including the 2D NMR techniques. The absolute configurations of 1 and 2 were determined by spectral and chemical methods. Anabaenopeptins I and J inhibited CPA with IC(50) values of 5.2 and 7.6 ng/mL, respectively.

  4. N,O-diacylated-N-hydroxyarylsulfonamides: nitroxyl precursors with potent smooth muscle relaxant properties

    Energy Technology Data Exchange (ETDEWEB)

    Fukuto, J.M.; Hszieh, R.; Gulati, P.; Chiang, K.T.; Nagasawa, H.T. (Department of Pharmacology, UCLA School of Medicine, Los Angeles, CA (United States))

    1992-09-30

    N,O-Diacylated-N-hydroxyarylsulfonamides are capable of slowly releasing nitroxyl (HNO) by simple, non-enzymatic hydrolysis in Krebs solution at 37 degrees C. Release of nitric oxide (NO) was not seen. These compounds were also found to elicit vasorelaxation in rabbit thoracic aorta in vitro, presumably as a result of their ability to release HNO. This effect was enhanced by the addition of superoxide dismutase (SOD). Thus, these results are consistent with previous work indicating that HNO is a potent vasorelaxant.

  5. Potent airway smooth muscle relaxant effect of cynatratoside B, a steroidal glycoside isolated from Cynanchum stauntonii.

    Science.gov (United States)

    Yue, Grace Gar-Lee; Chan, Kar-Man; To, Ming-Ho; Cheng, Ling; Fung, Kwok-Pui; Leung, Ping-Chung; Lau, Clara Bik-San

    2014-04-25

    The dried roots of Cynanchum stauntonii in having cough-relieving efficacy are commonly included in traditional antitussive formulas. The active components in a C. stauntonii root extract responsible for airway relaxation were isolated using an ex vivo bioassay-guided fractionation method, in which subfractions were evaluated for their inhibitory effects on the contraction of isolated rat tracheal rings by isometric tension measurements. A steroidal glycoside, cynatratoside B (1), identified by LC-MS and NMR spectroscopic analysis, was shown to have potent inhibition on acetylcholine- and carbachol-induced tracheal contractions. The present data provide scientific evidence to support the traditional use of C. stauntonii as an antitussive herbal medicine.

  6. 8-hydroxydihydrochelerythrine and 8-hydroxydihydrosanguinarine with a potent acetylcholinesterase inhibitory activity from Chelidonium majus L.

    Science.gov (United States)

    Cho, Kyung-Mi; Yoo, Ick-Dong; Kim, Won-Gon

    2006-11-01

    Ethanol extract of the aerial portion of Chelidonium majus L. inhibited acetylcholinesterase (AChE) activity without a significant inhibition of butyrylcholinesterase (BuChE). Using mass spectrometry and NMR studies, three active constituents were isolated and identified: 8-hydroxydihydrochelerythrine (1), 8-hydroxydihydrosanguinarine (2), and berberine (3). Compounds 1-3 showed potent inhibitory activity against AChE, with IC50 (microM) values of 0.61-1.85. Compound 1 exhibited competitive and selective inhibition for AChE.

  7. Ecteinascidins. A review of the chemistry, biology and clinical utility of potent tetrahydroisoquinoline antitumor antibiotics.

    Science.gov (United States)

    Le, V H; Inai, M; Williams, R M; Kan, T

    2015-02-01

    The ecteinascidin family comprises a number of biologically active compounds, containing two to three tetrahydroisoquinoline subunits. Although isolated from marine tunicates, these compounds share a common pentacyclic core with several antimicrobial compounds found in terrestrial bacteria. Among the tetrahydroisoquinoline natural products, ecteinascidin 743 (Et-743) stands out as the most potent antitumor antibiotics that it is recently approved for treatment of a number of soft tissue sarcomas. In this article, we will review the backgrounds, the mechanism of action, the biosynthesis, and the synthetic studies of Et-743. Also, the development of Et-743 as an antitumor drug is discussed.

  8. 5-Amino-pyrazoles as potent and selective p38[alpha] inhibitors

    Energy Technology Data Exchange (ETDEWEB)

    Das, Jagabandhu; Moquin, Robert V.; Dyckman, Alaric J.; Li, Tianle; Pitt, Sidney; Zhang, Rosemary; Shen, Ding Ren; McIntyre, Kim W.; Gillooly, Kathleen; Doweyko, Arthur M.; Newitt, John A.; Sack, John S.; Zhang, Hongjian; Kiefer, Susan E.; Kish, Kevin; McKinnon, Murray; Barrish, Joel C.; Dodd, John H.; Schieven, Gary L.; Leftheris, Katerina (BMS)

    2012-02-07

    The synthesis and structure-activity relationships (SAR) of p38{alpha} MAP kinase inhibitors based on a 5-amino-pyrazole scaffold are described. These studies led to the identification of compound 2j as a potent and selective inhibitor of p38{alpha} MAP kinase with excellent cellular potency toward the inhibition of TNF{alpha} production. Compound 2j was highly efficacious in vivo in inhibiting TNF{alpha} production in an acute murine model of TNF{alpha} production. X-ray co-crystallography of a 5-amino-pyrazole analog 2f bound to unphosphorylated p38{alpha} is also disclosed.

  9. Resveratrol and novel potent activators of SIRT1: effects on aging and age-related diseases.

    Science.gov (United States)

    Knutson, Mitchell D; Leeuwenburgh, Christiaan

    2008-10-01

    Studies show that the plant polyphenol resveratrol can extend the life span of yeast, worms, flies, and fish. It also mitigates the metabolic dysfunction of mice fed high-fat diets. Resveratrol appears to mediate these effects partly by activating SIRT1, a deacetylase enzyme that regulates the activity of several transcriptional factors and enzymes responsive to nutrient availability. However, few foods contain resveratrol and humans metabolize it extensively, resulting in very low systemic bioavailability. Substantial research effort now focuses on identifying and testing more bioavailable and potent activators of SIRT1 for use as pharmacologic interventions in aging and age-related disorders.

  10. Discovery of new SCH 39166 analogs as potent and selective dopamine D1 receptor antagonists.

    Science.gov (United States)

    Qiang, Li; Sasikumar, T K; Burnett, Duane A; Su, Jing; Tang, Haiqun; Ye, Yuanzan; Mazzola, Robert D; Zhu, Zhaoning; McKittrick, Brian A; Greenlee, William J; Fawzi, Ahmad; Smith, Michelle; Zhang, Hongtao; Lachowicz, Jean E

    2010-02-01

    A series of novel dopamine D(1) antagonists derived from functionalization of the D-ring of SCH 39166 were prepared. A number of these compounds displayed subnanomolar D(1) activity and more than 1000-fold selectivity over D(2). We found C-3 derivatization afforded compounds with superior overall profile in comparison to the C-2 and C-4 derivatization. A number of highly potent D(1) antagonists were discovered which have excellent selectivity over other dopamine receptors and improved PK profile compared to SCH 39166.

  11. Structure-Activity Relationships of Pentacyclic Triterpenoids as Potent and Selective Inhibitors against Human Carboxylesterase 1.

    Science.gov (United States)

    Zou, Li-Wei; Dou, Tong-Yi; Wang, Ping; Lei, Wei; Weng, Zi-Miao; Hou, Jie; Wang, Dan-Dan; Fan, Yi-Ming; Zhang, Wei-Dong; Ge, Guang-Bo; Yang, Ling

    2017-01-01

    Human carboxylesterase 1 (hCE1), one of the most important serine hydrolases distributed in liver and adipocytes, plays key roles in endobiotic homeostasis and xenobiotic metabolism. This study aimed to find potent and selective inhibitors against hCE1 from phytochemicals and their derivatives. To this end, a series of natural triterpenoids were collected and their inhibitory effects against human carboxylesterases (hCEs) were assayed using D-Luciferin methyl ester (DME) and 6,8-dichloro-9,9-dimethyl-7-oxo-7,9-dihydroacridin-2-yl benzoate (DDAB) as specific optical substrate for hCE1, and hCE2, respectively. Following screening of a series of natural triterpenoids, oleanolic acid (OA), and ursolic acid (UA) were found with strong inhibitory effects on hCE1 and relative high selectivity over hCE2. In order to get the highly selective and potent inhibitors of hCE1, a series of OA and UA derivatives were synthesized from OA and UA by chemical modifications including oxidation, reduction, esterification, and amidation. The inhibitory effects of these derivatives on hCEs were assayed and the structure-activity relationships of tested triterpenoids as hCE1 inhibitors were carefully investigated. The results demonstrated that the carbonyl group at the C-28 site is essential for hCE1 inhibition, the modifications of OA or UA at this site including esters, amides and alcohols are unbeneficial for hCE1 inhibition. In contrast, the structural modifications on OA and UA at other sites, such as converting the C-3 hydroxy group to 3-O-β-carboxypropionyl (compounds 20 and 22), led to a dramatically increase of the inhibitory effects against hCE1 and very high selectivity over hCE2. 3D-QSAR analysis of all tested triterpenoids including OA and UA derivatives provide new insights into the fine relationships linking between the inhibitory effects on hCE1 and the steric-electrostatic properties of triterpenoids. Furthermore, both inhibition kinetic analyses and docking simulations

  12. Structure-Activity Relationships of Pentacyclic Triterpenoids as Potent and Selective Inhibitors against Human Carboxylesterase 1

    Directory of Open Access Journals (Sweden)

    Li-Wei Zou

    2017-06-01

    Full Text Available Human carboxylesterase 1 (hCE1, one of the most important serine hydrolases distributed in liver and adipocytes, plays key roles in endobiotic homeostasis and xenobiotic metabolism. This study aimed to find potent and selective inhibitors against hCE1 from phytochemicals and their derivatives. To this end, a series of natural triterpenoids were collected and their inhibitory effects against human carboxylesterases (hCEs were assayed using D-Luciferin methyl ester (DME and 6,8-dichloro-9,9-dimethyl-7-oxo-7,9-dihydroacridin-2-yl benzoate (DDAB as specific optical substrate for hCE1, and hCE2, respectively. Following screening of a series of natural triterpenoids, oleanolic acid (OA, and ursolic acid (UA were found with strong inhibitory effects on hCE1 and relative high selectivity over hCE2. In order to get the highly selective and potent inhibitors of hCE1, a series of OA and UA derivatives were synthesized from OA and UA by chemical modifications including oxidation, reduction, esterification, and amidation. The inhibitory effects of these derivatives on hCEs were assayed and the structure-activity relationships of tested triterpenoids as hCE1 inhibitors were carefully investigated. The results demonstrated that the carbonyl group at the C-28 site is essential for hCE1 inhibition, the modifications of OA or UA at this site including esters, amides and alcohols are unbeneficial for hCE1 inhibition. In contrast, the structural modifications on OA and UA at other sites, such as converting the C-3 hydroxy group to 3-O-β-carboxypropionyl (compounds 20 and 22, led to a dramatically increase of the inhibitory effects against hCE1 and very high selectivity over hCE2. 3D-QSAR analysis of all tested triterpenoids including OA and UA derivatives provide new insights into the fine relationships linking between the inhibitory effects on hCE1 and the steric-electrostatic properties of triterpenoids. Furthermore, both inhibition kinetic analyses and docking

  13. Model for Osteosarcoma-9 as a potent factor in cell survival and resistance to apoptosis

    Science.gov (United States)

    Vourvouhaki, Ekaterini; Carvalho, Carla; Aguiar, Paulo

    2007-07-01

    In this paper we use a simple model to explore the function of the gene Osteosarcoma-9 (OS-9). We are particularly interested in understanding the role of this gene as a potent anti-apoptotic factor. The theoretical description is constrained by experimental data from induction of apoptosis in cells where OS-9 is overexpressed. The data available suggest that OS-9 promotes cell viability and confers resistance to apoptosis, potentially implicating OS-9 in the survival of cancer cells. Three different apoptosis-inducing mechanisms were tested and are modeled here. A more complex and realistic model is also discussed.

  14. Synthesis and biological evaluation of novel beta-carbolines as potent cytotoxic and DNA intercalating agents.

    Science.gov (United States)

    Chen, Zhiyong; Cao, Rihui; Shi, Buxi; Yi, Wei; Yu, Liang; Song, Huacan; Ren, Zhenhua

    2010-07-01

    A series of novel water-soluble beta-carbolines bearing a flexible amino side chain was designed, synthesized and evaluated as potent cytotoxic and DNA intercatalating agents. The N(9)-arylated alkyl substituted beta-carbolines represented the most interesting cytotoxic activities. The results suggested that (1) the N(9)-arylated alkyl substituents of beta-carboline nucleus played a very important role in the modulation of the cytotoxic potencies; (2) the length of the alkylamino side chain significantly affected their cytotoxic potency, and N,N-dimethylaminopropylamino substituent were more favorable. In addition, these compounds were found to exhibit significant DNA intercalating potencies.

  15. Prophylactic treatment with a potent corticosteroid cream ameliorates radiodermatitis, independent of radiation schedule

    DEFF Research Database (Denmark)

    Ulff, Eva; Maroti, Marianne; Serup, Jörgen;

    2016-01-01

    schedules as well as for anatomical sites, skin type, breast size and BMI. Patients treated the irradiated area during the radiation period and two weeks following cessation of radiation. RESULTS: Patients receiving hypofraction RT developed less skin reactions than those treated with conventional RT...... in patients with breast cancer receiving adjuvant radiotherapy (RT) after surgery. In total, 202 patients were randomized to betamethasone-17-valerate cream or Essex® cream, a moisturizer. Treatment was assessed by RTOG clinical scoring. Patients' symptoms were recorded. The analyses were stratified for RT....... Treatment with a potent steroid resulted in clinically and statistically significantly less skin reactions (p

  16. Crystal structure of HIV-1 primary receptor CD4 in complex with a potent antiviral antibody

    OpenAIRE

    Freeman, Michael M.; Seaman, Michael S; Rits-Volloch, Sophia; Hong, Xinguo; Kao, Chia-Ying; Ho, David D.; Chen, Bing

    2010-01-01

    Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 Å resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121-125) of D2, sitting...

  17. Aryl Pyrazoles as Potent Inhibitors of Arginine Methyltransferases: Identification of the First PRMT6 Tool Compound.

    Science.gov (United States)

    Mitchell, Lorna H; Drew, Allison E; Ribich, Scott A; Rioux, Nathalie; Swinger, Kerren K; Jacques, Suzanne L; Lingaraj, Trupti; Boriack-Sjodin, P Ann; Waters, Nigel J; Wigle, Tim J; Moradei, Oscar; Jin, Lei; Riera, Tom; Porter-Scott, Margaret; Moyer, Mikel P; Smith, Jesse J; Chesworth, Richard; Copeland, Robert A

    2015-06-11

    A novel aryl pyrazole series of arginine methyltransferase inhibitors has been identified. Synthesis of analogues within this series yielded the first potent, selective, small molecule PRMT6 inhibitor tool compound, EPZ020411. PRMT6 overexpression has been reported in several cancer types suggesting that inhibition of PRMT6 activity may have therapeutic utility. Identification of EPZ020411 provides the field with the first small molecule tool compound for target validation studies. EPZ020411 shows good bioavailability following subcutaneous dosing in rats making it a suitable tool for in vivo studies.

  18. Evaluation of the analgesic effects of ammoxetine, a novel potent serotonin and norepinephrine reuptake inhibitor

    OpenAIRE

    Zhang, Ting-Ting; Xue, Rui; Zhu, Lei; Li, Juan; Fan, Qiong-yin; Zhong, Bo-hua; Li, Yun-Feng; Ye, Cai-ying; Zhang, You-zhi

    2016-01-01

    Aim: The selective serotonin (5-HT) and norepinephrine (NE) reuptake inhibitors (SNRIs) are commonly used for the treatment of neuropathic pain and fibromyalgia. Ammoxetine ((±)-3-(benzo[d] [1,3]dioxol-4-yloxy)-N-methyl-3-(thiophen-2-yl)propan-1-amine) has been identified as a novel potent SNRI. In this study, we evaluated the acute analgesic properties of ammoxetine in different animal models of pain, and examined the involvement of monoamines in its analgesic actions. Methods: The analgesic...

  19. Discovery of S-444823, a potent CB1/CB2 dual agonist as an antipruritic agent.

    Science.gov (United States)

    Odan, Masahide; Ishizuka, Natsuki; Hiramatsu, Yoshiharu; Inagaki, Masanao; Hashizume, Hiroshi; Fujii, Yasuhiko; Mitsumori, Susumu; Morioka, Yasuhide; Soga, Masahiko; Deguchi, Masashi; Yasui, Kiyoshi; Arimura, Akinori

    2012-04-15

    The optimization of a series of 3-carbamoyl 2-pyridone derivatives as CB agonists is reported. These efforts resulted in the discovery of 3-(2-(1-(cyclohexylmethyl)-2-oxo-1,2,5,6,7,8,9,10-octahydrocycloocta[b]pyridine-3-carboxamido)thiazol-4-yl)propanoic acid (21), a potent dual CB1/CB2 agonist without CNS side effects induced by CB1 receptor activation. It exhibited strong inhibition of scratching as a 1.0% acetone solution in the pruritic model.

  20. Synthesis and biology of cyclic imine toxins, an emerging class of potent, globally distributed marine toxins.

    Science.gov (United States)

    Stivala, Craig E; Benoit, Evelyne; Aráoz, Rómulo; Servent, Denis; Novikov, Alexei; Molgó, Jordi; Zakarian, Armen

    2015-03-01

    From a small group of exotic compounds isolated only two decades ago, Cyclic Imine (CI) toxins have become a major class of marine toxins with global distribution. Their distinct chemical structure, biological mechanism of action, and intricate chemistry ensures that CI toxins will continue to be the subject of fascinating fundamental studies in the broad fields of chemistry, chemical biology, and toxicology. The worldwide occurrence of potent CI toxins in marine environments, their accumulation in shellfish, and chemical stability are important considerations in assessing risk factors for human health. This review article aims to provide an account of chemistry, biology, and toxicology of CI toxins from their discovery to the present day.

  1. Swinholide J, a Potent Cytotoxin from the Marine Sponge Theonella swinhoei

    Directory of Open Access Journals (Sweden)

    Angela Zampella

    2011-06-01

    Full Text Available In our ongoing search for new pharmacologically active leads from Solomon organisms, we have examined the sponge Theonella swinhoei. Herein we report the isolation and structure elucidation of swinholide A (1 and one new macrolide, swinholide J (2. Swinholide J is an unprecedented asymmetric 44-membered dilactone with an epoxide functionality in half of the molecule. The structural determination was based on extensive interpretation of high-field NMR spectra and HRESIMS data. Swinholide J displayed potent in vitro cytotoxicity against KB cells (human nasopharynx cancer with an IC50 value of 6 nM.

  2. Swinholide J, a potent cytotoxin from the marine sponge Theonella swinhoei.

    Science.gov (United States)

    De Marino, Simona; Festa, Carmen; D'Auria, Maria Valeria; Cresteil, Thierry; Debitus, Cecile; Zampella, Angela

    2011-01-01

    In our ongoing search for new pharmacologically active leads from Solomon organisms, we have examined the sponge Theonella swinhoei. Herein we report the isolation and structure elucidation of swinholide A (1) and one new macrolide, swinholide J (2). Swinholide J is an unprecedented asymmetric 44-membered dilactone with an epoxide functionality in half of the molecule. The structural determination was based on extensive interpretation of high-field NMR spectra and HRESIMS data. Swinholide J displayed potent in vitro cytotoxicity against KB cells (human nasopharynx cancer) with an IC(50) value of 6 nM.

  3. Structural Basis for the Potent and Selective Inhibition of Casein Kinase 1 Epsilon

    Energy Technology Data Exchange (ETDEWEB)

    Long, Alexander M. [Amgen Inc., Cambridge, MA (United States); Zhao, Huilin [Amgen Inc., Cambridge, MA (United States); Huang, Xin [Amgen Inc., Cambridge, MA (United States)

    2012-10-29

    Casein kinase 1 epsilon (CK1ε) and its closest homologue CK1δ are key regulators of diverse cellular processes. We report two crystal structures of PF4800567, a potent and selective inhibitor of CK1ε, bound to the kinase domains of human CK1ε and CK1δ as well as one apo CK1ε crystal structure. These structures provide a molecular basis for the strong and specific inhibitor interactions with CK1ε and suggest clues for further development of CK1δ inhibitors.

  4. In Situ Click Chemistry for the Identification of a Potent D-Amino Acid Oxidase Inhibitor.

    Science.gov (United States)

    Toguchi, Shohei; Hirose, Tomoyasu; Yorita, Kazuko; Fukui, Kiyoshi; Sharpless, K Barry; Ōmura, Satoshi; Sunazuka, Toshiaki

    2016-07-01

    In situ click chemistry is a target-guided synthesis approach for discovering novel lead compounds by assembling organic azides and alkynes into triazoles inside the affinity site of target biogenic molecules such as proteins. We report in situ click chemistry screening with human D-amino acid oxidase (hDAO), which led to the identification of a more potent hDAO inhibitor. The hDAO inhibitors have chemotherapeutic potential as antipsychotic agents. The new inhibitor displayed competitive inhibition of hDAO and showed significantly increased inhibitory activity against hDAO compared with that of an anchor molecule of in situ click chemistry.

  5. Rational design and asymmetric synthesis of potent and neurotrophic ligands for FK506-binding proteins (FKBPs).

    Science.gov (United States)

    Pomplun, Sebastian; Wang, Yansong; Kirschner, Alexander; Kozany, Christian; Bracher, Andreas; Hausch, Felix

    2015-01-01

    To create highly efficient inhibitors for FK506-binding proteins, a new asymmetric synthesis for pro-(S)-C(5) -branched [4.3.1] aza-amide bicycles was developed. The key step of the synthesis is an HF-driven N-acyliminium cyclization. Functionalization of the C(5)  moiety resulted in novel protein contacts with the psychiatric risk factor FKBP51, which led to a more than 280-fold enhancement in affinity. The most potent ligands facilitated the differentiation of N2a neuroblastoma cells with low nanomolar potency.

  6. Biological evaluation of some uracil derivatives as potent glutathione reductase inhibitors

    Science.gov (United States)

    Güney, Murat; Ekinci, Deniz; Ćavdar, Huseyin; Şentürk, Murat; Zilbeyaz, Kani

    2016-04-01

    Discovery of glutathione reductase (GR) inhibitors has become very popular recently due to antimalarial and anticancer activities. In this study, GR inhibitory capacities of some uracil derivatives (UDCs) (1-4) were reported. Some commercially available molecules (5-6) were also tested for comparison reasons. The novel UDCs were obtained in high yields using simple chemical procedures and exhibited much potent inhibitory activities against GR at low nanomolar concentrations with IC50 values ranging from 2.68 to 166.6 nM as compared with well-known agents.

  7. New benzothiazole/thiazole-containing hydroxamic acids as potent histone deacetylase inhibitors and antitumor agents

    DEFF Research Database (Denmark)

    Thanh Tung, Truong; Oanh, Dao Thi Kim; Dung, Phan Thi Phuong;

    2013-01-01

    Results from clinical studies have demonstrated that inhibitors of histone deacetylase (HDAC) enzymes possess promise for the treatment of several types of cancer. Zolinza(®) (widely known as SAHA) has been approved by the FDA for the treatment of T-cell lymphoma. As a continuity of our ongoing...... research to find novel small molecules to target these important enzymes, we synthesized a series of benzothiazole-containing analogues of SAHA and found several compounds with very potent anticancer cytotoxicity. In this study, three more compounds of this type, including N(1)-(6-chlorobenzo[d]thiazol-2...

  8. Identification of a potent immunostimulatory oligodeoxynucleotide from Streptococcus thermophilus lacZ.

    Science.gov (United States)

    Shimosato, Takeshi; Tohno, Masanori; Sato, Takashi; Nishimura, Junko; Kawai, Yasushi; Saito, Tadao; Kitazawa, Haruki

    2009-10-01

    Immunostimulatory sequences of oligodeoxynucleotides (ODNs), such as CpG ODNs, are potent stimulators of innate immunity. Here, we identified a strong immunostimulatory CpG ODN, which we named MsST, from the lac Z gene of Streptococcus (S.) thermophilus ATCC19258, and we evaluated its immune functions. In in vitro studies, MsST had a similar ability as the murine prototype CpG ODN 1555 to induce inflammatory cytokine production and cell proliferation. In mouse splenocytes, MsST increased the number of CD80+CD11c+and CD86+CD11c+ dendritic cells and CD4+CD25+ regulatory T cells. We also analyzed the effects of MsST on the expression of regulatory cytokines by real-time quantitative PCR. MsST was more potent at inducing interleukin-10 expression than the ODN control 1612, indicating that MsST can augment the regulatory T cell response via Toll-like receptor 9, which plays an important role in suppressing T helper type 2 responses. These results suggest that S. thermophilus, whose genes include a strong Immunostimulatory sequence-ODN, is a good candidate for a starter culture to develop new physiologically functional foods and feeds.

  9. Fluconazole is a potent inhibitor of antipyrine metabolism in vivo in mice

    Energy Technology Data Exchange (ETDEWEB)

    La Delfa, I.; Zhu, Q.M.; Mo, Z.; Blaschke, T.F.

    1989-01-01

    Fluconazole, a bis-triazole antifungal, is distinguished from imidazole antifungals (e.g. ketoconazole) by its potency and pharmacokinetic characteristics. Imidazole-containing compounds are well documented to inhibit the hepatic cytochrome P-450-dependent enzyme system; whether this effect occurs with a bis-triazole agent is unknown. The (/sup 14/C)antipyrine breath test was employed to investigate the effects of fluconazole on this enzyme system in CD-1 male mice. Control, ketoconazole (100 mg/kg), and fluconazole (1 and 10 mg/kg) were studied in single- and multiple-dose experiments. Fluconazole had potent inhibitory effects on the total (mean = -73% +/- 2%), demethylase (mean = -90% +/- 2%), and nondemethylase (mean = -60% +/- 4%) elimination rate constants (all p less than 0.001). The fraction of the administered radioactivity excreted as /sup 14/CO/sub 2/ was decreased by 50-80% in the fluconazole groups (p less than 0.001). These effects were seen after single- and multiple-dose studies; however, return to baseline occurred more quickly in the multiple-dose group. These effects were significantly more pronounced than those observed with equipotent doses of ketoconazole. These results provide evidence that fluconazole is a potent, partially selective, and reversible inhibitor of the cytochrome P-450-dependent enzyme system in mice. Future studies will be required to assess this property and possible interactions with drugs metabolized by this enzyme system in humans.

  10. Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro

    Science.gov (United States)

    Elosta, Abdulhakim; Slevin, Mark; Rahman, Khalid; Ahmed, Nessar

    2017-01-01

    Protein glycation involves formation of early (Amadori) and late advanced glycation endproducts (AGEs) together with free radicals via autoxidation of glucose and Amadori products. Glycation and increased free radical activity underlie the pathogenesis of diabetic complications. This study investigated whether aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro in a cell-free system. Proteins were glycated by incubation with sugars (glucose, methylglyoxal or ribose) ±5–15 mg/mL of aged and fresh garlic extracts. Advanced glycation endproducts were measured using SDS-PAGE gels and by ELISA whereas Amadori products were assessed by the fructosamine method. Colorimetric methods were used to assess antioxidant activity, free radical scavenging capacity, protein-bound carbonyl groups, thiol groups and metal chelation activities in addition to phenolic, total flavonoid and flavonol content of aged and fresh garlic extracts. Aged garlic inhibited AGEs by 56.4% compared to 33.5% for an equivalent concentration of fresh garlic extract. Similarly, aged garlic had a higher total phenolic content (129 ± 1.8 mg/g) compared to fresh garlic extract (56 ± 1.2 mg/g). Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract and is more suitable for use in future in vivo studies. PMID:28051097

  11. JB-9322, a new selective histamine H2-receptor antagonist with potent gastric mucosal protective properties.

    Science.gov (United States)

    Palacios, B; Montero, M J; Sevilla, M A; Román, L S

    1995-05-01

    1. JB-9322 is a selective histamine H2-receptor antagonist with gastric antisecretory activity and mucosal protective properties. 2. The affinity of JB-9322 for the guinea-pig atria histamine H2-receptor was approximately 2 times greater than that of ranitidine. 3. In vivo, the ID50 value for the inhibition of gastric acid secretion in pylorus-ligated rats was 5.28 mg kg-1 intraperitoneally. JB-9322 also dose-dependently inhibited gastric juice volume and pepsin secretion. In gastric lumen-perfused rats, intravenous injection of JB-9322 dose-dependently reduced histamine-, pentagastrin- and carbachol-stimulated gastric acid secretion. 4. JB-9322 showed antiulcer activity against aspirin and indomethacin-induced gastric lesions and was more potent than ranitidine. 5. JB-9322 effectively inhibited macroscopic gastric haemorrhagic lesions induced by ethanol. Intraperitoneal injection was effective in preventing the lesions as well as oral treatment. The oral ID50 value for these lesions was 1.33 mg kg-1. By contrast, ranitidine (50 mg kg-1) failed to reduce these lesions. In addition, the protective effect of JB-9322 was independent of prostaglandin synthesis. 6. These results indicate that JB-9322 is a new antiulcer drug that exerts a potent cytoprotective effect in addition to its gastric antisecretory activity.

  12. Basis Tetrapeptides as Potent Intracellular Inhibitors of type A Botulinum Neurotoxin Protease Activity

    Energy Technology Data Exchange (ETDEWEB)

    Hale, M.; Swaminathan, S.; Oyler, G.; Ahmed, S. A.

    2011-01-21

    Botulinum neurotoxins (BoNT) are the most potent of all toxins that cause flaccid muscle paralysis leading to death. They are also potential biothreat agents. A systematic investigation of various short peptide inhibitors of the BoNT protease domain with a 17-residue peptide substrate led to arginine-arginine-glycine-cysteine having a basic tetrapeptide structure as the most potent inhibitor. When assayed in the presence of dithiothreitol (DTT), the inhibitory effect was drastically reduced. Replacing the terminal cysteine with one hydrophobic residue eliminated the DTT effect but with two hydrophobic residues made the pentapeptide a poor inhibitor. Replacing the first arginine with cysteine or adding an additional cysteine at the N terminus did not improve inhibition. When assessed using mouse brain lysates, the tetrapeptides also inhibited BoNT/A cleavage of the endogenous SNAP-25. The peptides penetrated the neuronal cell lines, N2A and BE(2)-M17, without adversely affecting metabolic functions as measured by ATP production and P-38 phosphorylation. Biological activity of the peptides persisted within cultured chick motor neurons and rat and mouse cerebellar neurons for more than 40 h and inhibited BoNT/A protease action inside the neurons in a dose- and time-dependent fashion. Our results define a tetrapeptide as the smallest peptide inhibitor in the backdrop of a large substrate protein of 200+ amino acids having multiple interaction regions with its cognate enzyme. The inhibitors should also be valuable candidates for drug development.

  13. Effect of Potent Ethyl Acetate Fraction of Stereospermum suaveolens Extract in Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    T. Balasubramanian

    2012-01-01

    Full Text Available To evaluate the antihyperglycemic effect of ethyl acetate fraction of ethanol extract of Stereospermum suaveolens in streptozotocin-(STZ- induced diabetic rats by acute and subacute models. In this paper, various fractions of ethanol extract of Stereospermum suaveolens were prepared and their effects on blood glucose levels in STZ-induced diabetic rats were studied after a single oral administration (200?mg/kg. Administration of the ethyl acetate fraction at 200?mg/kg once daily for 14 days to STZ-induced diabetic rats was also carried out. The parameters such as the fasting blood glucose, hepatic glycogen content, and pancreatic antioxidant levels were monitored. In the acute study, the ethyl acetate fraction is the most potent in reducing the fasting serum glucose levels of the STZ-induced diabetic rats. The 14-day repeated oral administration of the ethyl acetate fraction significantly reduced the fasting blood glucose and pancreatic TBARS level and significantly increased the liver glycogen, pancreatic superoxide dismutase, and catalase activities as well as reduced glutathione levels. The histopathological studies during the subacute treatment have been shown to ameliorate the STZ-induced histological damage of pancreas. This paper concludes that the ethyl acetate fraction from ethanol extract of Stereospermum suaveolens possesses potent antihyperglycemic and antioxidant properties, thereby substantiating the use of plant in the indigenous system of medicine.

  14. Design of new and potent diethyl thiobarbiturates as urease inhibitors: a computational approach.

    Science.gov (United States)

    Wadood, Abdul; Riaz, Muhammad; Mulk, Amir Ul; Khan, Momin; Haleem, Sobia Ahsan; Shams, Sulaiman; Gul, Sahib; Ahmed, Ayaz; Qasim, Muhammad; Ali, Farman; Ul-Haq, Zaheer

    2014-01-01

    Urease is an important enzyme both in agriculture and medicine research. Strategies based on urease inhibition is critically considered as the first line treatment of infections caused by urease producing bacteria. Since, urease possess agro-chemical and medicinal importance, thus, it is necessary to search for the novel compounds capable of inhibiting this enzyme. Several computational methods were employed to design novel and potent urease inhibitors in this work. First docking simulations of known compounds consists of a set of arylidine barbiturates (termed as reference) were performed on the Bacillus pasteurii (BP) urease. Subsequently, two fold strategies were used to design new compounds against urease. Stage 1 comprised of the energy minimization of enzyme-ligand complexes of reference compounds and the accurate prediction of the molecular mechanics generalized born (MMGB) interaction energies. In the second stage, new urease inhibitors were then designed by the substitution of different groups consecutively in the aryl ring of the thiobarbiturates and N, N-diethyl thiobarbiturates of the reference ligands.. The enzyme-ligand complexes with lowest interaction energies or energies close to the calculated interaction energies of the reference molecules, were selected for the consequent chemical manipulation. This was followed by the substitution of different groups on the 2 and 5 positions of the aryl ring. As a result, several new and potent diethyl thiobarbiturates were predicted as urease inhibitors. This approach reflects a logical progression for early stage drug discovery that can be exploited to successfully identify potential drug candidates.

  15. Rice Bran Protein as a Potent Source of Antimelanogenic Peptides with Tyrosinase Inhibitory Activity.

    Science.gov (United States)

    Ochiai, Akihito; Tanaka, Seiya; Tanaka, Takaaki; Taniguchi, Masayuki

    2016-10-28

    Rice (Oryza sativa) is consumed as a staple food globally, and rice bran, the byproduct, is an unused biomass that is ultimately discarded as waste. Thus, in the present study, a technique for producing tyrosinase inhibitory peptides from rice bran protein (RBP) was developed. Simultaneous treatment of RBP with chymotrypsin and trypsin produced numerous peptides. Subsequently, six tyrosinase inhibitory peptides were isolated from the hydrolysate fractions in a multistep purification protocol, and their amino acid sequences were determined. Three of these peptides had a C-terminal tyrosine residue and exhibited significant inhibitory effects against tyrosinase-mediated monophenolase reactions. Furthermore, peptide CT-2 (Leu-Gln-Pro-Ser-His-Tyr) potently inhibited melanogenesis in mouse B16 melanoma cells without causing cytotoxicity, suggesting the potential of CT-2 as an agent for melanin-related skin disorder treatment. The present data indicate that RBP is a potent source of tyrosinase inhibitory peptides and that simultaneous treatment of RBP with chymotrypsin and trypsin efficiently produces these peptides.

  16. ABT-378, a Highly Potent Inhibitor of the Human Immunodeficiency Virus Protease

    Science.gov (United States)

    Sham, Hing L.; Kempf, Dale J.; Molla, Akhteruzammen; Marsh, Kennan C.; Kumar, Gondi N.; Chen, Chih-Ming; Kati, Warren; Stewart, Kent; Lal, Ritu; Hsu, Ann; Betebenner, David; Korneyeva, Marina; Vasavanonda, Sudthida; McDonald, Edith; Saldivar, Ayda; Wideburg, Norm; Chen, Xiaoqi; Niu, Ping; Park, Chang; Jayanti, Venkata; Grabowski, Brian; Granneman, G. Richard; Sun, Eugene; Japour, Anthony J.; Leonard, John M.; Plattner, Jacob J.; Norbeck, Daniel W.

    1998-01-01

    The valine at position 82 (Val 82) in the active site of the human immunodeficiency virus (HIV) protease mutates in response to therapy with the protease inhibitor ritonavir. By using the X-ray crystal structure of the complex of HIV protease and ritonavir, the potent protease inhibitor ABT-378, which has a diminished interaction with Val 82, was designed. ABT-378 potently inhibited wild-type and mutant HIV protease (Ki = 1.3 to 3.6 pM), blocked the replication of laboratory and clinical strains of HIV type 1 (50% effective concentration [EC50], 0.006 to 0.017 μM), and maintained high potency against mutant HIV selected by ritonavir in vivo (EC50, ≤0.06 μM). The metabolism of ABT-378 was strongly inhibited by ritonavir in vitro. Consequently, following concomitant oral administration of ABT-378 and ritonavir, the concentrations of ABT-378 in rat, dog, and monkey plasma exceeded the in vitro antiviral EC50 in the presence of human serum by >50-fold after 8 h. In healthy human volunteers, coadministration of a single 400-mg dose of ABT-378 with 50 mg of ritonavir enhanced the area under the concentration curve of ABT-378 in plasma by 77-fold over that observed after dosing with ABT-378 alone, and mean concentrations of ABT-378 exceeded the EC50 for >24 h. These results demonstrate the potential utility of ABT-378 as a therapeutic intervention against AIDS. PMID:9835517

  17. An Amphotericin B Derivative Equally Potent to Amphotericin B and with Increased Safety

    Science.gov (United States)

    Antillón, Armando; de Vries, Alexander H.; Espinosa-Caballero, Marcel; Falcón-González, José Marcos; Flores Romero, David; González–Damián, Javier; Jiménez-Montejo, Fabiola Eloísa; León-Buitimea, Angel; López-Ortiz, Manuel; Magaña, Ricardo; Marrink, Siewert J.; Morales-Nava, Rosmarbel; Periole, Xavier; Reyes-Esparza, Jorge; Rodríguez Lozada, Josué; Santiago-Angelino, Tania Minerva; Vargas González, María Cristina; Regla, Ignacio; Carrillo-Tripp, Mauricio; Fernández-Zertuche, Mario; Rodríguez-Fragoso, Lourdes; Ortega-Blake, Iván

    2016-01-01

    Amphotericin B is the most potent antimycotic known to date. However due to its large collateral toxicity, its use, although long standing, had been limited. Many attempts have been made to produce derivatives with reduced collateral damage. The molecular mechanism of polyene has also been closely studied for this purpose and understanding it would contribute to the development of safe derivatives. Our study examined polyene action, including chemical synthesis, electrophysiology, pharmacology, toxicology and molecular dynamics. The results were used to support a novel Amphotericin B derivative with increased selectivity: L-histidine methyl ester of Amphotericin B. We found that this derivative has the same form of action as Amphotericin B, i.e. pore formation in the cell membrane. Its reduced dimerization in solution, when compared to Amphotericin B, is at least partially responsible for its increased selectivity. Here we also present the results of preclinical tests, which show that the derivative is just as potent as Amphotericin B and has increased safety. PMID:27683101

  18. Second generation hybrid polar compounds are potent inducers of transformed cell differentiation.

    Science.gov (United States)

    Richon, V M; Webb, Y; Merger, R; Sheppard, T; Jursic, B; Ngo, L; Civoli, F; Breslow, R; Rifkind, R A; Marks, P A

    1996-06-11

    Hybrid polar compounds, of which hexamethylenebisacetamide (HMBA) is the prototype, are potent inducers of differentiation of murine erythroleukemia (MEL) cells and a wide variety of other transformed cells. HMBA has been shown to induce differentiation of neoplastic cells in patients, but is not an adequate therapeutic agent because of dose-limiting toxicity. We report on a group of three potent second generation hybrid polar compounds, diethyl bis-(pentamethylene-N,N-dimethylcarboxamide) malonate (EMBA), suberoylanilide hydroxamic acid (SAHA), and m-carboxycinnamic acid bis-hydroxamide (CBHA) with optimal concentrations for inducing MEL cells of 0.4 mM, 2 microM, and 4 microM, respectively, compared to 5 mM for HMBA. All three agents induce accumulation of underphosphorylated pRB; increased levels of p2l protein, a prolongation of the initial G1 phase of the cell cycle; and accumulation of hemoglobin. However, based upon their effective concentrations, the cross-resistance or sensitivity of an HMBA-resistant MEL cell variant, and differences in c-myb expression during induction, these differentiation-inducing hybrid polar compounds can be grouped into two subsets, HMBA/EMBA and SAHA/CBHA. This classification may prove of value in selecting and planning prospective preclinical and clinical studies toward the treatment of cancer by differentiation therapy.

  19. Potent antimicrobial peptides against Legionella pneumophila and its environmental host, Acanthamoeba castellanii.

    Science.gov (United States)

    Schlusselhuber, Margot; Humblot, Vincent; Casale, Sandra; Méthivier, Christophe; Verdon, Julien; Leippe, Matthias; Berjeaud, Jean-Marc

    2015-06-01

    Legionella pneumophila, the major causative agent of Legionnaires' disease, is most often found in the environment in close association with free-living amoebae, leading to persistence, spread, biocide resistance, and elevated virulence of the bacterium. In the present study, we evaluated the anti-Legionella and anti-Acanthamoeba activities of three alpha-helical antimicrobial peptides (AMPs), namely, NK-2, Ci-MAM-A24, and Ci-PAP-A22, already known for the extraordinary efficacy against other microbes. Our data represent the first demonstration of the activity of a particular AMP against both the human facultative intracellular pathogen L. pneumophila and its pathogenic host, Acanthamoeba castellanii. Interestingly, the most effective peptide, Ci-MAM-A24, was also found to reduce the Legionella cell number within amoebae. Accordingly, this peptide was immobilized on gold surfaces to assess its antimicrobial activity. Surfaces were characterized, and activity studies revealed that the potent bactericidal activity of the peptide was conserved after its immobilization. In the frame of elaborating anti-Legionella surfaces, Ci-MAM-A24 represents, by its direct and indirect activity against Legionella, a potent peptide template for biological control of the bacterium in plumbings.

  20. Highly potent inhibitors of methionine aminopeptidase-2 based on a 1,2,4-triazole pharmacophore.

    Science.gov (United States)

    Marino, Joseph P; Fisher, Paul W; Hofmann, Glenn A; Kirkpatrick, Robert B; Janson, Cheryl A; Johnson, Randall K; Ma, Chun; Mattern, Michael; Meek, Thomas D; Ryan, M Dominic; Schulz, Christina; Smith, Ward W; Tew, David G; Tomazek, Thaddeus A; Veber, Daniel F; Xiong, Wenfang C; Yamamoto, Yuuichi; Yamashita, Keizo; Yang, Guang; Thompson, Scott K

    2007-08-09

    High-throughput screening for inhibitors of the human metalloprotease, methionine aminopeptidase-2 (MetAP2), identified a potent class of 3-anilino-5-benzylthio-1,2,4-triazole compounds. Efficient array and interative synthesis of triazoles led to rapid SAR development around the aniline, benzylthio, and triazole moeities. Evaluation of these analogs in a human MetAP2 enzyme assay led to the identification of several inhibitors with potencies in the 50-100 picomolar range. The deleterious effects on inhibitor potency by methylation of the anilino-triazole nitrogens, as well as the X-ray crystal structure of triazole 102 bound in the active site of MetAP2, confirm the key interactions between the triazole nitrogens, the active site cobalt atoms, and the His-231 side-chain. The structure has also provided a rationale for interpreting SAR within the triazole series. Key aniline (2-isopropylphenyl) and sulfur substituents (furanylmethyl) identified in the SAR studies led to the identification of potent inhibitors (103 and 104) of endothelial cell proliferation. Triazoles 103 and 104 also exhibited dose-dependent activity in an aortic ring tissue model of angiogenesis highlighting the potential utility of MetAP2 inhibitors as anticancer agents.

  1. MONNA, a potent and selective blocker for transmembrane protein with unknown function 16/anoctamin-1.

    Science.gov (United States)

    Oh, Soo-Jin; Hwang, Seok Jin; Jung, Jonghoon; Yu, Kuai; Kim, Jeongyeon; Choi, Jung Yoon; Hartzell, H Criss; Roh, Eun Joo; Lee, C Justin

    2013-11-01

    Transmembrane protein with unknown function 16/anoctamin-1 (ANO1) is a protein widely expressed in mammalian tissues, and it has the properties of the classic calcium-activated chloride channel (CaCC). This protein has been implicated in numerous major physiological functions. However, the lack of effective and selective blockers has hindered a detailed study of the physiological functions of this channel. In this study, we have developed a potent and selective blocker for endogenous ANO1 in Xenopus laevis oocytes (xANO1) using a drug screening method we previously established (Oh et al., 2008). We have synthesized a number of anthranilic acid derivatives and have determined the correlation between biological activity and the nature and position of substituents in these derived compounds. A structure-activity relationship revealed novel chemical classes of xANO1 blockers. The derivatives contain a --NO₂ group on position 5 of a naphthyl group-substituted anthranilic acid, and they fully blocked xANO1 chloride currents with an IC₅₀ protein 2, and cystic fibrosis transmembrane conductance regulator were not appreciably blocked by 10∼30 μM MONNA. The potent and selective blockers for ANO1 identified here should permit pharmacological dissection of ANO1/CaCC function and serve as potential candidates for drug therapy of related diseases such as hypertension, cystic fibrosis, bronchitis, asthma, and hyperalgesia.

  2. Oxime Ethers of (E)-11-Isonitrosostrychnine as Highly Potent Glycine Receptor Antagonists.

    Science.gov (United States)

    Mohsen, Amal M Y; Mandour, Yasmine M; Sarukhanyan, Edita; Breitinger, Ulrike; Villmann, Carmen; Banoub, Maha M; Breitinger, Hans-Georg; Dandekar, Thomas; Holzgrabe, Ulrike; Sotriffer, Christoph; Jensen, Anders A; Zlotos, Darius P

    2016-12-23

    A series of (E)-11-isonitrosostrychnine oxime ethers, 2-aminostrychnine, (strychnine-2-yl)propionamide, 18-oxostrychnine, and N-propylstrychnine bromide were synthesized and evaluated pharmacologically at human α1 and α1β glycine receptors in a functional fluorescence-based and a whole-cell patch-clamp assay and in [(3)H]strychnine binding studies. 2-Aminostrychnine and the methyl, allyl, and propargyl oxime ethers were the most potent α1 and α1β antagonists in the series, displaying IC50 values similar to those of strychnine at the two receptors. Docking experiments to the strychnine binding site of the crystal structure of the α3 glycine receptor indicated the same orientation of the strychnine core for all analogues. For the most potent oxime ethers, the ether substituent was accommodated in a lipophilic receptor binding pocket. The findings identify the oxime hydroxy group as a suitable attachment point for linking two strychnine pharmacophores by a polymethylene spacer and are, therefore, important for the design of bivalent ligands targeting glycine receptors.

  3. Intracerebroventricular administration of chicken glucagon-like peptide-2 potently suppresses food intake in chicks.

    Science.gov (United States)

    Honda, Kazuhisa; Saneyasu, Takaoki; Shimatani, Tomohiko; Aoki, Koji; Yamaguchi, Takuya; Nakanishi, Kiwako; Kamisoyama, Hiroshi

    2015-03-01

    Glucagon-related peptides, such as glucagon-like peptide (GLP)-1, GLP-2 and oxyntomodulin (OXM), are processed from an identical precursor proglucagon. In mammals, all of these peptides are suggested to be involved in the central regulation of food intake. We previously showed that intracerebroventricular administration of chicken OXM and GLP-1 significantly suppressed food intake in chicks. Here, we show that central administration of chicken GLP-2 potently suppresses food intake in chicks. Male 8-day-old chicks (Gallus gallus domesticus) were used in all experiments. Intracerebroventricular administration of chicken GLP-2 significantly suppressed food intake in chicks. Plasma glucose concentration was significantly decreased by chicken GLP-2, whereas plasma nonesterified fatty acid concentration was significantly increased. Intracerebroventricular administration of chicken GLP-2 did not affect plasma corticosterone concentration. In addition, the anorexigenic effect of GLP-2 was not reversed by the corticotropin-releasing factor (CRF) receptor antagonist α-helical CRF, suggesting that CRF is not a downstream mediator of the anorexigenic pathway of GLP-2 in chicks. Intracerebroventricular administration of an equimolar amount of GLP-1 and GLP-2, but not OXM, significantly suppressed food intake in both broiler and layer chicks. All our findings suggest that GLP-2 functions as a potent anorexigenic peptide in the brain, as well as GLP-1, in chicks.

  4. Potent Inhibitor of Drug-Resistant HIV-1 Strains Identified from the Medicinal Plant Justicia gendarussa.

    Science.gov (United States)

    Zhang, Hong-Jie; Rumschlag-Booms, Emily; Guan, Yi-Fu; Wang, Dong-Ying; Liu, Kang-Lun; Li, Wan-Fei; Nguyen, Van H; Cuong, Nguyen M; Soejarto, Djaja D; Fong, Harry H S; Rong, Lijun

    2017-06-23

    Justicia gendarussa, a medicinal plant collected in Vietnam, was identified as a potent anti-HIV-1 active lead from the evaluation of over 4500 plant extracts. Bioassay-guided separation of the extracts of the stems and roots of this plant led to the isolation of an anti-HIV arylnaphthalene lignan (ANL) glycoside, patentiflorin A (1). Evaluation of the compound against both the M- and T-tropic HIV-1 isolates showed it to possess a significantly higher inhibition effect than the clinically used anti-HIV drug AZT. Patentiflorin A and two congeners were synthesized, de novo, as an efficient strategy for resupply as well as for further structural modification of the anti-HIV ANL glycosides in the search for drug leads. Subsequently, it was determined that the presence of a quinovopyranosyloxy group in the structure is likely essential to retain the high degree of anti-HIV activity of this type of compounds. Patentiflorin A was further investigated against the HIV-1 gene expression of the R/U5 and U5/gag transcripts, and the data showed that the compound acts as a potential inhibitor of HIV-1 reverse transcription. Importantly, the compound displayed potent inhibitory activity against drug-resistant HIV-1 isolates of both the nucleotide analogue (AZT) and non-nucleotide analogue (nevaripine). Thus, the ANL glycosides have the potential to be developed as novel anti-HIV drugs.

  5. Design and Synthesis of Mercaptoacetamides as Potent, Selective, and Brain Permeable Histone Deacetylase 6 Inhibitors.

    Science.gov (United States)

    Lv, Wei; Zhang, Guangming; Barinka, Cyril; Eubanks, James H; Kozikowski, Alan P

    2017-05-11

    A series of nonhydroxamate HDAC6 inhibitors were prepared in our effort to develop potent and selective compounds for possible use in central nervous system (CNS) disorders, thus obviating the genotoxicity often associated with the hydroxamates. Halogens are incorporated in the cap groups of the designed mercaptoacetamides in order to increase brain accessibility. The indole analogue 7e and quinoline analogue 13a displayed potent HDAC6 inhibitory activity (IC50, 11 and 2.8 nM) and excellent selectivity against HDAC1. Both 7e and 13a together with their ester prodrug 14 and disulfide prodrugs 15 and 16 were found to be effective in promoting tubulin acetylation in HEK cells. The disulfide prodrugs 15 and 16 also released a stable concentration of 7e and 13a upon microsomal incubation. Administration of 15 and 16in vivo was found to trigger an increase of tubulin acetylation in mouse cortex. These results suggest that further exploration of these compounds for the treatment of CNS disorders is warranted.

  6. Climbazole is a new potent inducer of rat hepatic cytochrome P450.

    Science.gov (United States)

    Kobayashi, Y; Suzuki, M; Ohshiro, N; Sunagawa, T; Sasaki, T; Tokuyama, S; Yamamoto, T; Yoshida, T

    2001-08-01

    We examined the effect of climbazole on the induction of rat hepatic microsomal cytochrome P450 (P450), and compared the induction potency with other N-substituted azole drugs such as clorimazole. We found that climbazole is found to be a potent inducer of rat hepatic microsomal P450 as clorimazole. Induced level of P450 by climbazole was almost similar in extent to clorimazole when compared with other imidazole drugs in a dose- and time-dependent manner. Parallel to the increase in P450, climbazole increased aminopyrine and erythromycin N-demethylase, ethoxycoumarin O-deethylase, and androstenedione 16 beta- and 15 alpha/6 beta hydroxylase activities; however, clorimazole did not induce aminopyrine N-demethylase activity irrespective of its marked increase in P450 content. Immunoblot analyses revealed that climbazole induced CYP2B1, 3A2 and 4A1. The present findings indicate that climbazole is a new potent inducer of hepatic microsomal P450 and drug-metabolizing enzymes like clorimazole, but it may have some differential mechanism(s) for these enzymes' induction in rat liver.

  7. A Nonpolycationic Fully Proteinaceous Multiagent System for Potent Targeted Delivery of siRNA

    Science.gov (United States)

    Liu, David V; Yang, Nicole J; Wittrup, K Dane

    2014-01-01

    Protein-based methods of targeted short-interfering RNA (siRNA) delivery have the potential to solve some of the problems faced by nanoparticle-based methods, such as poor pharmacokinetics and biodistribution, low tumor penetration, and polydispersity. However, protein-based targeted delivery has been limited to fusion proteins with polycationic peptides as siRNA carriers, whose high charge density in some cases results in undesirable biophysical and in vivo properties. Here, we present a fully proteinaceous, multiagent approach for targeted siRNA delivery to epidermal growth factor receptor (EGFR), using a nonpolycationic carrier for siRNA. Each agent contributes a fundamentally different mechanism of action that work together for potent targeted RNA interference. The first agent is an EGFR-targeted fusion protein that uses a double-stranded RNA-binding domain as a nonpolycationic siRNA carrier. This double-stranded RNA-binding domain fusion protein can deliver siRNA to the endosomes of an EGFR-expressing cell line. A second agent delivers the cholesterol-dependent cytolysin, perfringolysin O, in a targeted manner, which enhances the endosomal escape of siRNA and induces gene silencing. A third agent that clusters EGFR increases gene-silencing potency and decreases cytolysin toxicity. Altogether, this system is potent, with only 16 nmol/l siRNA required for gene silencing and a therapeutic window that spans two orders of magnitude of targeted cytolysin concentrations. PMID:24825362

  8. Human pituitary tissue secretes a potent growth factor for chondrocyte proliferation.

    Science.gov (United States)

    Kasper, S; Friesen, H G

    1986-01-01

    We report the secretion from human pituitary tumor fragments in organ culture of a potent mitogen for chondrocyte proliferation. Primary human pituitary cell and organ cultures were established from pituitary fragments obtained from patients with acromegaly, prolactinomas, and nonfunctional adenomas. The conditioned culture medium contained a mitogenic factor(s) that stimulated rabbit fetal chondrocyte proliferation, causing up to an 8-fold increase in cell number when added to Ham's F-10 medium in the presence of 10% fetal bovine serum. Blood leaking into the surgical field after the adenomectomy is known to contain very high concentrations of pituitary hormones. Serum samples, obtained from this venous "ooze" collected at the site of pituitary surgery, also were found to contain chondrocyte growth-promoting activity. Some venous serum samples stimulated chondrocyte proliferation in a dose-dependent manner down to a 1:10 dilution of 1 microliter serum, indicating that the material being secreted was very potent indeed. Gel filtration on Sephadex G-100 and analytical gel isoelectric focusing of culture media or serum samples from the pituitary fossa demonstrated that the growth factor secreted from the pituitary tumor fragments as well as from the venous serum is similar, if not identical, to chondrocyte growth factor (mol wt, 43,000; pI 7.6-7.9) purified from human pituitaries collected at autopsy. These results suggest that the chondrocyte growth-promoting factor(s) may not only be secreted by pituitary tumor fragments but by normal human pituitary tissue as well.

  9. Potent macrocyclic inhibitors of insulin-regulated aminopeptidase (IRAP) by olefin ring-closing metathesis.

    Science.gov (United States)

    Andersson, Hanna; Demaegdt, Heidi; Johnsson, Anders; Vauquelin, Georges; Lindeberg, Gunnar; Hallberg, Mathias; Erdelyi, Mate; Karlen, Anders; Hallberg, Anders

    2011-06-01

    Macrocyclic analogues of angiotensin IV (Ang IV, Val(1)-Tyr(2)-Ile(3)-His(4)-Pro(5)-Phe(6)) targeting the insulin-regulated aminopeptidase (IRAP) have been designed, synthesized, and evaluated biologically. Replacement of His(4)-Pro(5)-Phe(6) by a 2-(aminomethyl)phenylacetic acid (AMPAA) moiety and of Val(1) and Ile(3) by amino acids bearing olefinic side chains followed by macrocyclization provided potent IRAP inhibitors. The impact of the ring size and the type (saturated versus unsaturated), configuration, and position of the carbon-carbon bridge was assessed. The ring size generally affects the potency more than the carbon-carbon bond characteristics. Replacing Tyr(2) by β(3)hTyr or Phe is accepted, while N-methylation of Tyr(2) is deleterious for activity. Removal of the carboxyl group in the C-terminal slightly reduced the potency. Inhibitors 7 (K(i) = 4.1 nM) and 19 (K(i) = 1.8 nM), both encompassing 14-membered ring systems connected to AMPAA, are 10-fold more potent than Ang IV and are also more selective over aminopeptidase N (AP-N). Both compounds displayed high stability against proteolysis by metallopeptidases.

  10. Discovery of Potent and Selective Inhibitors for G9a-Like Protein (GLP) Lysine Methyltransferase

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Yan; Li, Fengling; Babault, Nicolas; Dong, Aiping; Zeng, Hong; Wu, Hong; Chen, Xin; Arrowsmith, Cheryl H.; Brown, Peter J.; Liu, Jing; Vedadi, Masoud; Jin, Jian

    2017-02-14

    G9a-like protein (GLP) and G9a are highly homologous protein lysine methyltransferases (PKMTs) sharing approximately 80% sequence identity in their catalytic domains. GLP and G9a form a heterodimer complex and catalyze mono- and dimethylation of histone H3 lysine 9 and nonhistone substrates. Although they are closely related, GLP and G9a possess distinct physiological and pathophysiological functions. Thus, GLP or G9a selective small-molecule inhibitors are useful tools to dissect their distinct biological functions. We previously reported potent and selective G9a/GLP dual inhibitors including UNC0638 and UNC0642. Here we report the discovery of potent and selective GLP inhibitors including 4 (MS0124) and 18 (MS012), which are >30-fold and 140-fold selective for GLP over G9a and other methyltransferases, respectively. The cocrystal structures of GLP and G9a in the complex with either 4 or 18 displayed virtually identical binding modes and interactions, highlighting the challenges in structure-based design of selective inhibitors for either enzyme.

  11. In vitro examination of potentized atropine sulfate dilutions on the contractility of the isolated rat ileum.

    Science.gov (United States)

    Siegling-Vlitakis, Christiane; Martens, Holger; Lüdtke, Rainer

    2009-10-01

    Atropine sulphate, a competitive antagonist of acetylcholine (ACh) at muscarinic receptors, was first isolated from Atropa belladonna, one of the most used and best known homeopathic medicines. It has been suggested that high potencies of homeopathic atropine sulphate might have an influence on ACh-induced contraction of smooth muscles. The aim of the study was to determine the effects of homeopathic dilutions of atropine sulphate D6, D32, and D100 compared to the potentized diluents L6, L32, and L100 on ACh-induced contraction of isolated rat ileum. Forty-eight (48) ileal sections from 12 male Wistar rats were incubated in modified Krebs solutions, and the contractile activity responses to ACh obtained in the absence and presence of the test substances were recorded. Investigators and biometrician were completely blinded. No significant effects of atropine sulphate D6, D32, or D100 could be found (all p > 0.4 after Bonferoni-Holm correction) compared to the potentized diluents L6, L32, and L100, respectively. These figures did not change considerably even when strict a priori criteria were applied that define a measurement as valid and comparable. Our experiments could not replicate previous results on the effects of homeopathic atropine.

  12. New benzothiazole/thiazole-containing hydroxamic acids as potent histone deacetylase inhibitors and antitumor agents.

    Science.gov (United States)

    Tung, Truong Thanh; Oanh, Dao Thi Kim; Dung, Phan Thi Phuong; Hue, Van Thi My; Park, Sang Ho; Han, Byung Woo; Kim, Youngsoo; Hong, Jin-Tae; Han, Sang-Bae; Nam, Nguyen-Hai

    2013-12-01

    Results from clinical studies have demonstrated that inhibitors of histone deacetylase (HDAC) enzymes possess promise for the treatment of several types of cancer. Zolinza(®) (widely known as SAHA) has been approved by the FDA for the treatment of T-cell lymphoma. As a continuity of our ongoing research to find novel small molecules to target these important enzymes, we synthesized a series of benzothiazole-containing analogues of SAHA and found several compounds with very potent anticancer cytotoxicity. In this study, three more compounds of this type, including N(1)-(6-chlorobenzo[d]thiazol-2-yl)-N(8)-hydroxyoctanediamide (3a), N(1)-[6-(trifluoromethyl)benzo[d]thiazol-2-yl]-N(8)-hydroxyoctanediamide (3b) and N(1)-(thiazol-2-yl)-N(8)-hydroxyoctanediamide (6) were synthesized and evaluated for HDAC inhibition and cytotoxic activities. All three compounds showed very potent HDAC inhibitory effects. Docking revealed that both two compounds 3a, 3b showed higher affinities towards HDAC(8) compared to SAHA. In vitro, compound 3a exhibited cytotoxicity equipotent to SAHA against five human cancer cell lines. In term of in vivo activity, compound 3a demonstrated equivalent efficacy to SAHA in mouse xenograft model.

  13. Discovery of Potent Bruton's Tyrosine Kinase Inhibitors Using Ligand Based Modeling.

    Science.gov (United States)

    Mera, Wafa A; Alzihlif, Malek; Taha, Mutasem O; Khanfar, Mohammad A

    2017-01-01

    Bruton's Tyrosine Kinase (BTK) is a one of the Tec tyrosine kinase family. It has an essential role in B-cell development and function. Activation of BTK has been associated with the pathogenesis of many types of lymphomas and leukemia, and involved in non-life threatening autoimmune diseases. In this study, exhaustive pharmacophore modeling was combined with QSAR analyses to examine the structural requirements for anti-BTK activities. Genetic function algorithm (GFA) was coupled with multiple linear regression (MLR) analysis to select the best combinations of physicochemical descriptors and pharmacophoric hypothesis capable of generating predictive and self-consistent QSAR models. The optimum pharmacophores were decorated with exclusion volumes to improve their receiver operating characteristic (ROC) curve properties. The best predictive QSAR model and its corresponding pharmacophore models were validated by discovering of novel promising BTK inhibitors retrieved from the National Cancer Institute (NCI) database. Several potent hits exhibited anti-proliferative activities on U-937 cell-line in low micromolar IC50, and one active compound showed nontoxic activities on normal fibroblast cell line. Our efforts culminated in the identification of potent BTK ligands having desired inhibitory activities and structurally distinct from known active reference compounds (i.e., training compounds) and represent new chemotypes.

  14. Searching the Sequence Space for Potent Aptamers Using SELEX in Silico.

    Science.gov (United States)

    Zhou, Qingtong; Xia, Xiaole; Luo, Zhaofeng; Liang, Haojun; Shakhnovich, Eugene

    2015-12-08

    To isolate functional nucleic acids that bind to defined targets with high affinity and specificity, which are known as aptamers, the systematic evolution of ligands by exponential enrichment (SELEX) methodology has emerged as the preferred approach. Here, we propose a computational approach, SELEX in silico, that allows the sequence space to be more thoroughly explored regarding binding of a certain target. Our approach consists of two steps: (i) secondary structure-based sequence screening, which aims to collect the sequences that can form a desired RNA motif as an enhanced initial library, followed by (ii) sequence enrichment regarding target binding by molecular dynamics simulation-based virtual screening. Our SELEX in silico method provided a practical computational solution to three key problems in aptamer sequence searching: design of nucleic acid libraries, knowledge of sequence enrichment, and identification of potent aptamers. Six potent theophylline-binding aptamers, which were isolated by SELEX in silico from a sequence space containing 4(13) sequences, were experimentally verified to bind theophylline with high affinity: Kd ranging from 0.16 to 0.52 μM, compared with the dissociation constant of the original aptamer-theophylline, 0.32 μM. These results demonstrate the significant potential of SELEX in silico as a new method for aptamer discovery and optimization.

  15. Synthesis and characterization of phosphocitric acid, a potent inhibitor of hydroxylapatite crystal growth.

    Science.gov (United States)

    Tew, W P; Mahle, C; Benavides, J; Howard, J E; Lehninger, A L

    1980-04-29

    Human urine and extracts of rat liver mitochondria contain apparently identical agents capable of inhibiting the precipitation or crystallization of calcium phosphate. Its general properties, as well as 1H NMR and mass spectra, have suggested that the agent is phosphocitric acid. This paper reports the synthesis of phosphocitric acid via the phosphorylation of triethyl citrate with o-phenylene phosphochloridate, hydrogenolysis of the product to yield triethyl phosphocitrate, hydrolytic removal of the blocking ethyl groups and also chromatographic purification. An enzymatic assay of phosphocitrate is described. Synthetic phosphocitrate was found to be an exceedingly potent inhibitor of the growth of hydroxylapatite seed crystals in a medium supersaturated with respect to Ca2+ and phosphate. Comparative assays showed phosphocitrate to be much more potent than the most active precipitation-crystallization inhibitors previously reported, which include pyrophosphate and ATP. 14C-Labeled phosphocitrate was bound very tightly to hydroxylapatite crystals. Such binding appeared to be essential for its inhibitory activity on crystal growth. Citrate added before but not after, phosphocitrate greatly enhanced the inhibitory potency of the latter. This enhancement effect was not given by other tricarboxylic acids. The monoethyl ester of phosphocitrate had no inhibitory effect on hydroxylapatite crystal growth.

  16. Novel Radiolytic Rotenone Derivative, Rotenoisin B with Potent Anti-Carcinogenic Activity in Hepatic Cancer Cells

    Directory of Open Access Journals (Sweden)

    Srilatha Badaboina

    2015-07-01

    Full Text Available Rotenone, isolated from roots of derris plant, has been shown to possess various biological activities, which lead to attempting to develop a potent drug against several diseases. However, recent studies have demonstrated that rotenone has the potential to induce several adverse effects such as a neurodegenerative disease. Radiolytic transformation of the rotenone with gamma-irradiation created a new product, named rotenoisin B. The present work was designed to investigate the anticancer activity of rotenoisin B with low toxicity and its molecular mechanism in hepatic cancer cells compared to a parent compound, rotenone. Our results showed rotenoisin B inhibited hepatic cancer cells’ proliferation in a dose dependent manner and increased in apoptotic cells. Interestingly, rotenoisin B showed low toxic effects on normal cells compared to rotenone. Mitochondrial transmembrane potential has been decreased, which leads to cytochrome c release. Down regulation of anti-apoptotic Bcl-2 levels as well as the up regulation of proapoptotic Bax levels were observed. The cleaved PARP (poly ADP-ribose polymerase level increased as well. Moreover, phosphorylation of extracellular signal regulated kinase (ERK and p38 slightly up regulated and intracellular reactive oxygen species (ROS increased as well as cell cycle arrest predominantly at the G2/M phase observed. These results suggest that rotenoisin B might be a potent anticancer candidate similar to rotenone in hepatic cancer cells with low toxicity to normal cells even at high concentrations compared to rotenone.

  17. Potent T cell Responses Induced by Single DNA Vaccine Boosted with Recombinant Vaccinia Vaccine

    Institute of Scientific and Technical Information of China (English)

    Lianxing Liu; Chao Qiu; Yang Huang; Jianqing Xu; Yiming Shao

    2013-01-01

    Plasmid DNA,an effective vaccine vector,can induce both cellular and humoral immune responses.However,plasmid DNA raises issues concerning potential genomic integration after injection.This issue should be considered in preclinical studies.Tiantan vaccinia virus (TV) has been most widely utilized in eradicating smallpox in China.This virus has also been considered as a successful vaccine vector against a few infectious diseases.Potent T cell responses through T-cell receptor (TCR) could be induced by three injections of the DNA prime vaccine followed by a single injection of recombinant vaccinia vaccine.To develop a safer immunization strategy,a single DNA prime followed by a single recombinant Tiantan vaccinia (rTV) AIDS vaccine was used to immunize mice.Our data demonstrated that one DNA prime/rTV boost regimen induced mature TCR activation with high functional avidity,preferential T cell Vβ receptor usage and high sensitivity to anti-CD3 antibody stimulation.No differences in T cell responses were observed among one,two or three DNA prime/rTV boost regimens.This study shows that one DNA prime/rTV boost regimen is sufficient to induce potent T cell responses against HIV.

  18. Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro.

    Science.gov (United States)

    Elosta, Abdulhakim; Slevin, Mark; Rahman, Khalid; Ahmed, Nessar

    2017-01-04

    Protein glycation involves formation of early (Amadori) and late advanced glycation endproducts (AGEs) together with free radicals via autoxidation of glucose and Amadori products. Glycation and increased free radical activity underlie the pathogenesis of diabetic complications. This study investigated whether aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract in vitro in a cell-free system. Proteins were glycated by incubation with sugars (glucose, methylglyoxal or ribose) ±5-15 mg/mL of aged and fresh garlic extracts. Advanced glycation endproducts were measured using SDS-PAGE gels and by ELISA whereas Amadori products were assessed by the fructosamine method. Colorimetric methods were used to assess antioxidant activity, free radical scavenging capacity, protein-bound carbonyl groups, thiol groups and metal chelation activities in addition to phenolic, total flavonoid and flavonol content of aged and fresh garlic extracts. Aged garlic inhibited AGEs by 56.4% compared to 33.5% for an equivalent concentration of fresh garlic extract. Similarly, aged garlic had a higher total phenolic content (129 ± 1.8 mg/g) compared to fresh garlic extract (56 ± 1.2 mg/g). Aged garlic has more potent antiglycation and antioxidant properties compared to fresh garlic extract and is more suitable for use in future in vivo studies.

  19. Natural fatty acid synthase inhibitors as potent therapeutic agents for cancers: A review.

    Science.gov (United States)

    Zhang, Jia-Sui; Lei, Jie-Ping; Wei, Guo-Qing; Chen, Hui; Ma, Chao-Ying; Jiang, He-Zhong

    2016-09-01

    Context Fatty acid synthase (FAS) is the only mammalian enzyme to catalyse the synthesis of fatty acid. The expression level of FAS is related to cancer progression, aggressiveness and metastasis. In recent years, research on natural FAS inhibitors with significant bioactivities and low side effects has increasingly become a new trend. Herein, we present recent research progress on natural fatty acid synthase inhibitors as potent therapeutic agents. Objective This paper is a mini overview of the typical natural FAS inhibitors and their possible mechanism of action in the past 10 years (2004-2014). Method The information was collected and compiled through major databases including Web of Science, PubMed, and CNKI. Results Many natural products induce cancer cells apoptosis by inhibiting FAS expression, with fewer side effects than synthetic inhibitors. Conclusion Natural FAS inhibitors are widely distributed in plants (especially in herbs and foods). Some natural products (mainly phenolics) possessing potent biological activities and stable structures are available as lead compounds to synthesise promising FAS inhibitors.

  20. Dioscorea bulbifera Mediated Synthesis of Novel AucoreAgshell Nanoparticles with Potent Antibiofilm and Antileishmanial Activity

    Directory of Open Access Journals (Sweden)

    Sougata Ghosh

    2015-01-01

    Full Text Available Dioscorea bulbifera is a potent medicinal plant used in both Indian and Chinese traditional medicine owing to its rich phytochemical diversity. Herein, we report the rapid synthesis of novel AucoreAgshell nanoparticles by D. bulbifera tuber extract (DBTE. AucoreAgshell NPs synthesis was completed within 5 h showing a prominent peak at 540 nm. HRTEM analysis revealed 9 nm inner core of elemental gold covered by a silver shell giving a total particle diameter upto 15 nm. AucoreAgshellNPs were comprised of 57.34±1.01% gold and 42.66±0.97% silver of the total mass. AucoreAgshellNPs showed highest biofilm inhibition upto 83.68±0.09% against A. baumannii. Biofilms of P. aeruginosa, E. coli, and S. aureus were inhibited up to 18.93±1.94%, 22.33±0.56%, and 30.70±1.33%, respectively. Scanning electron microscopy (SEM and atomic force microscopy (AFM confirmed unregulated cellular efflux through pore formation leading to cell death. Potent antileishmanial activity of AucoreAgshellNPs (MIC=32 µg/mL was confirmed by MTT assay. Further SEM micrographs showed pronounced deformity in the spindle shaped cellular morphology changing to spherical. This is the first report of synthesis, characterization, antibiofilm, and antileishmanial activity of AucoreAgshellNPs synthesized by D. bulbifera.

  1. Nonhuman Primate IFITM Proteins Are Potent Inhibitors of HIV and SIV.

    Directory of Open Access Journals (Sweden)

    Jordan Wilkins

    Full Text Available Interferon-induced transmembrane (IFITM proteins are potent antiviral factors shown to restrict the infection of many enveloped viruses, including HIV. Here we report cloning and characterization of a panel of nonhuman primate IFITMs. We show that, similar to human IFITM, nonhuman primate IFITM proteins inhibit HIV and other primate lentiviruses. While some nonhuman primate IFITM proteins are more potent than human counterparts to inhibit HIV-1, they are generally not effective against HIV-2 similar to that of human IFITMs. Notably, depending on SIV strains and also IFITM species tested, nonhuman primate IFITM proteins exhibit distinct activities against SIVs; no correlation was found to support the notion that IFITM proteins are most active in non-natural primate hosts. Consistent with our recent findings for human IFITMs, nonhuman primate IFITM proteins interact with HIV-1 Env and strongly act in viral producer cells to impair viral infectivity and block cell-to-cell transmission. Accordingly, knockdown of primate IFITM3 increases HIV-1 replication in nohuman primate cells. Interestingly, analysis of DNA sequences of human and nonhuman primate IFITMs suggest that IFITM proteins have been undergoing purifying selection, rather than positive selection typical for cellular restriction factors. Overall, our study reveals some new and unexpected features of IFITMs in restricting primate lentiviruses, which enhances our understanding of virus-host interaction and AIDS pathogenesis.

  2. Rational Design of Potent and Selective Inhibitors of an Epoxide Hydrolase Virulence Factor from Pseudomonas aeruginosa.

    Science.gov (United States)

    Kitamura, Seiya; Hvorecny, Kelli L; Niu, Jun; Hammock, Bruce D; Madden, Dean R; Morisseau, Christophe

    2016-05-26

    The virulence factor cystic fibrosis transmembrane conductance regulator (CFTR) inhibitory factor (Cif) is secreted by Pseudomonas aeruginosa and is the founding member of a distinct class of epoxide hydrolases (EHs) that triggers the catalysis-dependent degradation of the CFTR. We describe here the development of a series of potent and selective Cif inhibitors by structure-based drug design. Initial screening revealed 1a (KB2115), a thyroid hormone analog, as a lead compound with low micromolar potency. Structural requirements for potency were systematically probed, and interactions between Cif and 1a were characterized by X-ray crystallography. On the basis of these data, new compounds were designed to yield additional hydrogen bonding with residues of the Cif active site. From this effort, three compounds were identified that are 10-fold more potent toward Cif than our first-generation inhibitors and have no detectable thyroid hormone-like activity. These inhibitors will be useful tools to study the pathological role of Cif and have the potential for clinical application.

  3. Novel Potent Hepatitis C Virus NS3 Serine Protease Inhibitors Derived from Proline-Based Macrocycles

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Kevin X.; Njoroge, F. George; Arasappan, Ashok; Venkatraman, Srikanth; Vibulbhan, Bancha; Yang, Weiying; Parekh, Tejal N.; Pichardo, John; Prongay, Andrew; Cheng, Kuo-Chi; Butkiewicz, Nancy; Yao, Nanhua; Madison, Vincent; Girijavallabhan, Viyyoor (SPRI)

    2008-06-30

    The hepatitis C virus (HCV) NS3 protease is essential for viral replication. It has been a target of choice for intensive drug discovery research. On the basis of an active pentapeptide inhibitor, 1, we envisioned that macrocyclization from the P2 proline to P3 capping could enhance binding to the backbone Ala156 residue and the S4 pocket. Thus, a number of P2 proline-based macrocyclic {alpha}-ketoamide inhibitors were prepared and investigated in an HCV NS3 serine protease continuous assay (K*{sub i}). The biological activity varied substantially depending on factors such as the ring size, number of amino acid residues, number of methyl substituents, type of heteroatom in the linker, P3 residue, and configuration at the proline C-4 center. The pentapeptide inhibitors were very potent, with the C-terminal acids and amides being the most active ones (24, K*{sub i} = 8 nM). The tetrapeptides and tripeptides were less potent. Sixteen- and seventeen-membered macrocyclic compounds were equally potent, while fifteen-membered analogues were slightly less active. gem-Dimethyl substituents at the linker improved the potency of all inhibitors (the best compound was 45, K*{sub i} = 6 nM). The combination of tert-leucine at P3 and dimethyl substituents at the linker in compound 47 realized a selectivity of 307 against human neutrophil elastase. Compound 45 had an IC{sub 50} of 130 nM in a cellular replicon assay, while IC{sub 50} for 24 was 400 nM. Several compounds had excellent subcutaneous AUC and bioavailability in rats. Although tripeptide compound 40 was 97% orally bioavailable, larger pentapeptides generally had low oral bioavailability. The X-ray crystal structure of compounds 24 and 45 bound to the protease demonstrated the close interaction of the macrocycle with the Ala156 methyl group and S4 pocket. The strategy of macrocyclization has been proved to be successful in improving potency (>20-fold greater than that of 1) and in structural depeptization.

  4. Potent inhibition of cytochrome P450 2B6 by sibutramine in human liver microsomes.

    Science.gov (United States)

    Bae, Soo Hyeon; Kwon, Min Jo; Choi, Eu Jin; Zheng, Yu Fen; Yoon, Kee Dong; Liu, Kwang-Hyeon; Bae, Soo Kyung

    2013-09-05

    The present study was performed to evaluate the potency and specificity of sibutramine as an inhibitor of the activities of nine human CYP isoforms in liver microsomes. Using a cocktail assay, the effects of sibutramine on specific marker reactions of the nine CYP isoforms were measured in human liver microsomes. Sibutramine showed potent inhibition of CYP2B6-mediated bupropion 6-hydroxylation with an IC50 value of 1.61μM and Ki value of 0.466μM in a competitive manner at microsomal protein concentrations of 0.25mg/ml; this was 3.49-fold more potent than the typical CYP2B6 inhibitor thio-TEPA (Ki=1.59μM). In addition, sibutramine slightly inhibited CYP2C19 activity (Ki=16.6μM, noncompetitive inhibition) and CYP2D6 activity (Ki=15.7μM, noncompetitive inhibition). These observations indicated 35.6- and 33.7-fold decreases in inhibition potency, respectively, compared with that of CYP2B6 by sibutramine. However, no inhibition of CYP1A2, CYP2A6, CYP2C8, CYP2C9, CYP2D6, or CYP2E1 activities was observed. In addition, the CYP2B6 inhibitory potential of sibutramine was enhanced at a lower microsomal protein concentration of 0.05mg/ml. After 30min preincubation of human liver microsomes with sibutramine in the presence of NADPH, no shift in IC50 was observed in terms of inhibition of the activities of the nine CYPs, suggesting that sibutramine is not a time-dependent inactivator. These observations suggest that sibutramine is a selective and potent inhibitor of CYP2B6 in vitro, whereas inhibition of other CYPs is substantially lower. These in vitro data support the use of sibutramine as a well-known inhibitor of CYP2B6 for routine screening of P450 reversible inhibition when human liver microsomes are used as the enzyme source.

  5. Identification and characterization of potent CYP3A4 inhibitors in Schisandra fruit extract.

    Science.gov (United States)

    Iwata, Hiroshi; Tezuka, Yasuhiro; Kadota, Shigetoshi; Hiratsuka, Akira; Watabe, Tadashi

    2004-12-01

    Schisandra fruit, a Schisandraceae family herb, is used as a component in Kampo medicines (developed from Chinese medicines, but established in Japan). It can act as a sedative and antitussive, improve hepatic function, and give a general tonic effect. An extract of Schisandra fruit has been shown with a potent inhibitory effect on human liver microsomal erythromycin N-demethylation activity mediated by cytochrome P450 3A4 (CYP3A4). The present study was conducted to identify Schisandra fruit components having inhibitory effects on CYP3A4 by surveying the effect on human liver microsomal erythromycin N-demethylation activity. Known components of Schisandra fruit, gomisins B, C, G, and N and gamma-shizandrin, showed inhibitory effects on N-demethylation activity. Among these components, gomisin C displayed the most potent and competitive inhibitory effect, with a Ki value of 0.049 microM. Furthermore, the inhibitory effect of gomisin C was stronger than that of ketoconazole (Ki = 0.070 microM), a known potent CYP3A4 inhibitor. Gomisin C, however, inhibited CYP1A2-, CYP2C9-, CYP2C19-, and CYP2D6-dependent activities only to a limited extent (IC50 values >10 microM). Moreover, gomisin C inactivated human liver microsomal erythromycin N-demethylation activity in a time- and concentration-dependent manner. The inactivation kinetic parameters k(inact) and K(I) were 0.092 min(-1) and 0.399 microM, respectively. The human liver microsomal erythromycin N-demethylation activity inactivated by gomisin C did not recover on dialysis of the microsomes. Spectral scanning of CYP3A4 with gomisin C yielded an absorbance at 455 nm, suggesting that gomisin C inactivated the cytochrome P450 via the formation of a metabolite intermediate complex. This pattern is consistent with the metabolism of the methylenedioxy substituent in gomisin C. These results indicate that gomisin C is a mechanism-based inhibitor that not only competitively inhibits but irreversibly inactivates CYP3A4.

  6. Targeting Two Coagulation Cascade Proteases with a Bivalent Aptamer Yields a Potent and Antidote-Controllable Anticoagulant.

    Science.gov (United States)

    Soule, Erin E; Bompiani, Kristin M; Woodruff, Rebecca S; Sullenger, Bruce A

    2016-02-01

    Potent and rapid-onset anticoagulation is required for several clinical settings, including cardiopulmonary bypass surgery. In addition, because anticoagulation is associated with increased bleeding following surgery, the ability to rapidly reverse such robust anticoagulation is also important. Previously, we observed that no single aptamer was as potent as heparin for anticoagulating blood. However, we discovered that combinations of two aptamers were as potent as heparin. Herein, we sought to combine two individual anticoagulant aptamers into a single bivalent RNA molecule in an effort to generate a single molecule that retained the potent anticoagulant activity of the combination of individual aptamers. We created four bivalent aptamers that can inhibit Factor X/Xa and prothrombin/thrombin and anticoagulate plasma, as well as the combination of individual aptamers. Detailed characterization of the shortest bivalent aptamer indicates that each aptamer retains full binding and functional activity when presented in the bivalent context. Finally, reversal of this bivalent aptamer with a single antidote was explored, and anticoagulant activity could be rapidly turned off in a dose-dependent manner. These studies demonstrate that bivalent anticoagulant aptamers represent a novel and potent approach to actively and reversibly control coagulation.

  7. Flavaglines: potent anticancer drugs that target prohibitins and the helicase eIF4A.

    Science.gov (United States)

    Basmadjian, Christine; Thuaud, Frédéric; Ribeiro, Nigel; Désaubry, Laurent

    2013-12-01

    Flavaglines are complex natural products that are found in several medicinal plants of Southeast Asia in the genus Aglaia; these compounds have shown exceptional anticancer and cytoprotective activities. This review describes the significance of flavaglines as a new class of pharmacological agents and presents recent developments in their synthesis, structure-activity relationships, identification of their molecular targets and modes of action. Flavaglines display a unique profile of anticancer activities that are mediated by two classes of unrelated proteins: prohibitins and the translation initiation factor eIF4A. The identification of these molecular targets is expected to accelerate advancement toward clinical studies. The selectivity of cytotoxicity towards cancer cells has been shown to be due to an inhibition of the transcription factor HSF1 and an upregulation of the tumor suppressor TXNIP. In addition, flavaglines display potent anti-inflammatory, cardioprotective and neuroprotective activities; however, the mechanisms underlying these activities are yet to be elucidated.

  8. Synthesis and biological evaluation of fluconazole analogs with triazole-modified scaffold as potent antifungal agents.

    Science.gov (United States)

    Hashemi, Seyedeh Mahdieh; Badali, Hamid; Irannejad, Hamid; Shokrzadeh, Mohammad; Emami, Saeed

    2015-04-01

    In order to find new azole antifungals, we have recently designed a series of triazole alcohols in which one of the 1,2,4-triazol-1-yl group in fluconazole structure has been replaced with 4-amino-5-aryl-3-mercapto-1,2,4-triazole motif. In this paper, we focused on the structural refinement of the primary lead, by removing the amino group from the structure to achieve 5-aryl-3-mercapto-1,2,4-triazole derivatives 10a-i and 11a-i. The in vitro antifungal susceptibility testing of title compounds demonstrated that most compounds had potent inhibitory activity against Candida species. Among them, 5-(2,4-dichlorophenyl)triazole analogs 10h and 11h with MIC values of fluconazole against Candida species.

  9. Activin is a potent growth suppressor of epithelial ovarian cancer cells.

    Science.gov (United States)

    Ramachandran, Anassuya; Marshall, Elaine S; Love, Donald R; Baguley, Bruce C; Shelling, Andrew N

    2009-11-28

    Although activin is a major cytokine produced by the ovary, its role in epithelial ovarian cancer is poorly defined. Here, we demonstrate a novel role for activin as a growth inhibitor of some (8/16) epithelial ovarian cancer cell lines. Unresponsive cell lines displayed transcriptional downregulation of the activin receptors ACTRIIA and ACTRIB, suggesting resistance to activin signalling. In response to activin, growth inhibited cell lines demonstrated activation of the canonical SMAD2/3/4, transcriptional induction of the CDK inhibitor p15INK4B, suppression of C-MYC levels and a G1 phase cell cycle arrest. Thus, activin is a potent inhibitor of proliferation of some epithelial ovarian cancer cell lines and its role in the pathogenesis of this disease needs to be re-evaluated.

  10. A highly potent and selective farnesyltransferase inhibitor ABT-100 in preclinical studies.

    Science.gov (United States)

    Gu, Wen-Zhen; Joseph, Ingrid; Wang, Yi-Chun; Frost, David; Sullivan, Gerard M; Wang, Le; Lin, Nan-Horng; Cohen, Jerry; Stoll, Vincent S; Jakob, Clarissa G; Muchmore, Steven W; Harlan, John E; Holzman, Tom; Walten, Karl A; Ladror, Uri S; Anderson, Mark G; Kroeger, Paul; Rodriguez, Luis E; Jarvis, Kenneth P; Ferguson, Debra; Marsh, Kennan; Ng, Shichung; Rosenberg, Saul H; Sham, Hing L; Zhang, Haiying

    2005-11-01

    Ras mutation has been detected in approximately 20-30% of all human carcinomas, primarily in pancreatic, colorectal, lung and bladder carcinomas. The indirect inhibition of Ras activity by inhibiting farnesyltransferase (FTase) function is one therapeutic intervention to control tumor growth. Here we report the preclinical anti-tumor activity of our most advanced FTase inhibitor (FTI), ABT-100, and a direct comparison with the current clinical candidates. ABT-100 is a highly selective, potent and orally bioavailable FTI. It broadly inhibits the growth of solid tumors in preclinical animal models. Thus, ABT-100 is an attractive candidate for further clinical evaluation. In addition, our results provide plausible insights to explain the impressive potency and selectivity of ABT-100. Finally, we have demonstrated that ABT-100 significantly suppresses the expression of vascular endothelial growth factor (VEGF) mRNA and secretion of VEGF protein, as well as inhibiting angiogenesis in the animal model.

  11. Designed, synthetically accessible bryostatin analogues potently induce activation of latent HIV reservoirs in vitro

    Science.gov (United States)

    Dechristopher, Brian A.; Loy, Brian A.; Marsden, Matthew D.; Schrier, Adam J.; Zack, Jerome A.; Wender, Paul A.

    2012-09-01

    Bryostatin is a unique lead in the development of potentially transformative therapies for cancer, Alzheimer's disease and the eradication of HIV/AIDS. However, the clinical use of bryostatin has been hampered by its limited supply, difficulties in accessing clinically relevant derivatives, and side effects. Here, we address these problems through the step-economical syntheses of seven members of a new family of designed bryostatin analogues using a highly convergent Prins-macrocyclization strategy. We also demonstrate for the first time that such analogues effectively induce latent HIV activation in vitro with potencies similar to or better than bryostatin. Significantly, these analogues are up to 1,000-fold more potent in inducing latent HIV expression than prostratin, the current clinical candidate for latent virus induction. This study provides the first demonstration that designed, synthetically accessible bryostatin analogues could serve as superior candidates for the eradication of HIV/AIDS through induction of latent viral reservoirs in conjunction with current antiretroviral therapy.

  12. Structure-based redesign of lysostaphin yields potent antistaphylococcal enzymes that evade immune cell surveillance

    Directory of Open Access Journals (Sweden)

    Kristina Blazanovic

    2015-01-01

    Full Text Available Staphylococcus aureus infections exert a tremendous burden on the health-care system, and the threat of drug-resistant strains continues to grow. The bacteriolytic enzyme lysostaphin is a potent antistaphylococcal agent with proven efficacy against both drug-sensitive and drug-resistant strains; however, the enzyme's own bacterial origins cause undesirable immunogenicity and pose a barrier to clinical translation. Here, we deimmunized lysostaphin using a computationally guided process that optimizes sets of mutations to delete immunogenic T cell epitopes without disrupting protein function. In vitro analyses showed the methods to be both efficient and effective, producing seven different deimmunized designs exhibiting high function and reduced immunogenic potential. Two deimmunized candidates elicited greatly suppressed proliferative responses in splenocytes from humanized mice, while at the same time the variants maintained wild-type efficacy in a staphylococcal pneumonia model. Overall, the deimmunized enzymes represent promising leads in the battle against S. aureus.

  13. Discovery of a Potent Class I Protein Arginine Methyltransferase Fragment Inhibitor.

    Science.gov (United States)

    Ferreira de Freitas, Renato; Eram, Mohammad S; Szewczyk, Magdalena M; Steuber, Holger; Smil, David; Wu, Hong; Li, Fengling; Senisterra, Guillermo; Dong, Aiping; Brown, Peter J; Hitchcock, Marion; Moosmayer, Dieter; Stegmann, Christian M; Egner, Ursula; Arrowsmith, Cheryl; Barsyte-Lovejoy, Dalia; Vedadi, Masoud; Schapira, Matthieu

    2016-02-11

    Protein methyltransferases (PMTs) are a promising target class in oncology and other disease areas. They are composed of SET domain methyltransferases and structurally unrelated Rossman-fold enzymes that include protein arginine methyltransferases (PRMTs). In the absence of a well-defined medicinal chemistry tool-kit focused on PMTs, most current inhibitors were identified by screening large and diverse libraries of leadlike molecules. So far, no successful fragment-based approach was reported against this target class. Here, by deconstructing potent PRMT inhibitors, we find that chemical moieties occupying the substrate arginine-binding site can act as efficient fragment inhibitors. Screening a fragment library against PRMT6 produced numerous hits, including a 300 nM inhibitor (ligand efficiency of 0.56) that decreased global histone 3 arginine 2 methylation in cells, and can serve as a warhead for the development of PRMT chemical probes.

  14. 2-(Hetero(aryl)methylene)hydrazine-1-carbothioamides as potent urease inhibitors.

    Science.gov (United States)

    Saeed, Aamer; Imran, Aqeel; Channar, Pervaiz A; Shahid, Mohammad; Mahmood, Wajahat; Iqbal, Jamshed

    2015-02-01

    A small series of 2-(hetero(aryl)methylene) hydrazine-1-carbothioamides including two aryl derivatives was synthesized and tested for their inhibitory activity against urease. Compound (E)-2-(Furan-2-ylmethylene) hydrazine-1-carbothioamide (3f), having a furan ring, was the most potent inhibitor of urease with an IC50 value of 0.58 μM. Molecular modeling was carried out through docking the designed compounds into the urease binding site to predict whether these derivatives have analogous binding mode to the urease inhibitors. The study revealed that all of the tested compounds bind with both metal atoms at the active site of the enzyme. The aromatic ring of the compounds forms ionic interactions with the residues, Ala(440), Asp(494), Ala(636), and Met(637).

  15. Synthesis, molecular docking and biological evaluation of metronidazole derivatives as potent Helicobacter pylori urease inhibitors.

    Science.gov (United States)

    Mao, Wen-Jun; Lv, Peng-Cheng; Shi, Lei; Li, Huan-Qiu; Zhu, Hai-Liang

    2009-11-01

    Fourteen metronidazole derivatives (compounds 3a-f and 4b-h) have been synthesized by coupling of metronidazole and salicylic acid derivatives. All of them are reported for the first time. Their chemical structures are characterized by (1)H NMR, MS, and elemental analysis. The inhibitory activities against Helicobacter pylori urease have been investigated in vitro and many compounds have showed promising potential inhibitory activities of H. pylori urease. The effect of compounds 4b (IC(50)=26 microM) and 4 g (IC(50)=12 microM) was comparable with that of acetohydroxamic acid, a well known H. pylori urease inhibitor used as a positive control. The experimental values of IC(50) showed that inhibitor was potent urease inhibitor. A docking analysis using the autodock 4.0 program could explain the inhibitory activities of compound 4 g against H. pylori urease.

  16. Potent Human α-Amylase Inhibition by the β-Defensin-like Protein Helianthamide.

    Science.gov (United States)

    Tysoe, Christina; Williams, Leslie K; Keyzers, Robert; Nguyen, Nham T; Tarling, Chris; Wicki, Jacqueline; Goddard-Borger, Ethan D; Aguda, Adeleke H; Perry, Suzanne; Foster, Leonard J; Andersen, Raymond J; Brayer, Gary D; Withers, Stephen G

    2016-03-23

    Selective inhibitors of human pancreatic α-amylase (HPA) are an effective means of controlling blood sugar levels in the management of diabetes. A high-throughput screen of marine natural product extracts led to the identification of a potent (Ki = 10 pM) peptidic HPA inhibitor, helianthamide, from the Caribbean sea anemone Stichodactyla helianthus. Active helianthamide was produced in Escherichia coli via secretion as a barnase fusion protein. X-ray crystallographic analysis of the complex of helianthamide with porcine pancreatic α-amylase revealed that helianthamide adopts a β-defensin fold and binds into and across the amylase active site, utilizing a contiguous YIYH inhibitory motif. Helianthamide represents the first of a novel class of glycosidase inhibitors and provides an unusual example of functional malleability of the β-defensin fold, which is rarely seen outside of its traditional role in antimicrobial peptides.

  17. Design and synthesis of potent inhibitors of the mono(ADP-ribosyl)transferase, PARP14.

    Science.gov (United States)

    Upton, Kristen; Meyers, Matthew; Thorsell, Ann-Gerd; Karlberg, Tobias; Holechek, Jacob; Lease, Robert; Schey, Garrett; Wolf, Emily; Lucente, Adrianna; Schüler, Herwig; Ferraris, Dana

    2017-07-01

    A series of (Z)-4-(3-carbamoylphenylamino)-4-oxobut-2-enyl amides were synthesized and tested for their ability to inhibit the mono-(ADP-ribosyl)transferase, PARP14 (a.k.a. BAL-2; ARTD-8). Two synthetic routes were established for this series and several compounds were identified as sub-micromolar inhibitors of PARP14, the most potent of which was compound 4t, IC50=160nM. Furthermore, profiling other members of this series identified compounds with >20-fold selectivity over PARP5a/TNKS1, and modest selectivity over PARP10, a closely related mono-(ADP-ribosyl)transferase. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Facile green synthesis of gold nanoparticles using leaf extract of antidiabetic potent Cassia auriculata.

    Science.gov (United States)

    Kumar, V Ganesh; Gokavarapu, S Dinesh; Rajeswari, A; Dhas, T Stalin; Karthick, V; Kapadia, Zainab; Shrestha, Tripti; Barathy, I A; Roy, Anindita; Sinha, Sweta

    2011-10-01

    A simple biological method for the synthesis of gold nanoparticles (AuNPs) using Cassia auriculata aqueous leaf extract has been carried out in the present study. The reduction of auric chloride led to the formation of AuNPs within 10 min at room temperature (28°C), suggesting a higher reaction rate than chemical methods involved in the synthesis. The size, shape and elemental analysis were carried out using X-ray diffraction, TEM, SEM-EDAX, FT-IR and visible absorption spectroscopy. Stable, triangular and spherical crystalline AuNPs with well-defined dimensions of average size of 15-25 nm were synthesized using C. auriculata. Effect of pH was also studied to check the stability of AuNPs. The main aim of the investigation is to synthesize AuNPs using antidiabetic potent medicinal plant. The stabilizing and reducing molecules of nanoparticles may promote anti-hyperglycemic if tested further.

  19. Echinacea—A Source of Potent Antivirals for Respiratory Virus Infections

    Directory of Open Access Journals (Sweden)

    Selvarani Vimalanathan

    2011-07-01

    Full Text Available Extracts of Echinacea species have been used traditionally in North America for the control of symptoms of colds, influenza, and other diseases, and some of them have become very popular as “herbal medicines”. Recent studies have revealed that preparations derived from certain species and plant parts, but not all of them, possess potent antiviral activities, at non-cytotoxic concentrations, particularly against membrane-containing viruses. Thus all strains of human and avian influenza viruses tested (including a Tamiflu-resistant strain, as well as herpes simplex virus, respiratory syncytial virus, and rhinoviruses, were very sensitive to a standardized Echinacea purpurea preparation. In mechanistic studies the influenza virus-specific hemagglutinin and neuraminidase were inhibited. In addition some extracts displayed anti-inflammatory activity in virus-infected cells, and numerous other effects on the expression of cellular genes. Multiple components, either discrete compounds or mixtures, appeared to be responsible for the various antiviral activities.

  20. Synthetic N-Alkyl/aralkyl-4-methyl-N-(naphthalen-1-ylbenzenesulfonamides as Potent Antibacterial Agents

    Directory of Open Access Journals (Sweden)

    *M. A. Abbasi

    2015-03-01

    Full Text Available The current research effort involved the reaction of napthalen-1-amine (1 with 4-methylbenzenesulfonyl chloride (2 under dynamic pH control at 9-10, maintained with 10% aqueous Na2CO3 to obtain 4-methyl-N-(naphthalen-1-yl benzenesulfonamide (3. The parent molecule 3 was further substituted at N-atom with alkyl/aralkyl halides (4a-f in polar aprotic solvent; N,N-dimethylformamide, and lithium hydride which acts as a base, to achieve N-alkyl/aralkyl-4-methyl-N-(naphthalen-1-ylbenzenesulfonamides (5a-f. All the synthesized compounds were structurally elucidated by IR, 1H-NMR and EIMS spectral techniques. All the derivatives were further screened for antibacterial and anti-enzymatic potential against various bacterial strains and enzymes, respectively, and were found to be potent antibacterial agents and moderate to weak enzyme inhibitors.

  1. Discovery of Potent and Highly Selective A2B Adenosine Receptor Antagonist Chemotypes.

    Science.gov (United States)

    El Maatougui, Abdelaziz; Azuaje, Jhonny; González-Gómez, Manuel; Miguez, Gabriel; Crespo, Abel; Carbajales, Carlos; Escalante, Luz; García-Mera, Xerardo; Gutiérrez-de-Terán, Hugo; Sotelo, Eddy

    2016-03-10

    Three novel families of A2B adenosine receptor antagonists were identified in the context of the structural exploration of the 3,4-dihydropyrimidin-2(1H)-one chemotype. The most appealing series contain imidazole, 1,2,4-triazole, or benzimidazole rings fused to the 2,3-positions of the parent diazinone core. The optimization process enabled identification of a highly potent (3.49 nM) A2B ligand that exhibits complete selectivity toward A1, A2A, and A3 receptors. The results of functional cAMP experiments confirmed the antagonistic behavior of representative ligands. The main SAR trends identified within the series were substantiated by a molecular modeling study based on a receptor-driven docking model constructed on the basis of the crystal structure of the human A2A receptor.

  2. Biotin analogues with antibacterial activity are potent inhibitors of biotin protein ligase.

    Science.gov (United States)

    Soares da Costa, Tatiana P; Tieu, William; Yap, Min Y; Zvarec, Ondrej; Bell, Jan M; Turnidge, John D; Wallace, John C; Booker, Grant W; Wilce, Matthew C J; Abell, Andrew D; Polyak, Steven W

    2012-06-14

    There is a desperate need to develop new antibiotic agents to combat the rise of drug-resistant bacteria, such as clinically important Staphylococcus aureus. The essential multifunctional enzyme, biotin protein ligase (BPL), is one potential drug target for new antibiotics. We report the synthesis and characterization of a series of biotin analogues with activity against BPLs from S. aureus, Escherichia coli, and Homo sapiens. Two potent inhibitors with K i 20-fold selectivity between the isozymes were identified and characterized. The antibacterial mode of action was shown to be via inhibition of BPL. The bimolecular interactions between the BPL and the inhibitors were defined by surface plasmon resonance studies and X-ray crystallography. These findings pave the way for second-generation inhibitors and antibiotics with greater potency and selectivity.

  3. Identification of potent Yes1 kinase inhibitors using a library screening approach.

    Science.gov (United States)

    Patel, Paresma R; Sun, Hongmao; Li, Samuel Q; Shen, Min; Khan, Javed; Thomas, Craig J; Davis, Mindy I

    2013-08-01

    Yes1 kinase has been implicated as a potential therapeutic target in a number of cancers including melanomas, breast cancers, and rhabdomyosarcomas. Described here is the development of a robust and miniaturized biochemical assay for Yes1 kinase that was applied in a high throughput screen (HTS) of kinase-focused small molecule libraries. The HTS provided 144 (17% hit rate) small molecule compounds with IC₅₀ values in the sub-micromolar range. Three of the most potent Yes1 inhibitors were then examined in a cell-based assay for inhibition of cell survival in rhabdomyosarcoma cell lines. Homology models of Yes1 were generated in active and inactive conformations, and docking of inhibitors supports binding to the active conformation (DFG-in) of Yes1. This is the first report of a large high throughput enzymatic activity screen for identification of Yes1 kinase inhibitors, thereby elucidating the polypharmacology of a variety of small molecules and clinical candidates.

  4. Novel highly potent serotonin 5-HT7 receptor ligands: structural modifications to improve pharmacokinetic properties.

    Science.gov (United States)

    Lacivita, Enza; Di Pilato, Pantaleo; Stama, Madia Letizia; Colabufo, Nicola Antonio; Berardi, Francesco; Perrone, Roberto; De Filippis, Bianca; Laviola, Giovanni; Adriani, Walter; Niso, Mauro; Leopoldo, Marcello

    2013-11-15

    Here we report the synthesis, pharmacological and pharmacokinetic evaluation of a pilot set of compounds structurally related to the potent and selective 5-HT7 ligand LP-211. Among the studied compounds, N-pyridin-3-ylmethyl-3-[4-[2-(4-methoxyphenyl)phenyl]piperazin-1-yl]ethoxy]propanamide (4b) showed high affinity for 5-HT7 receptors (K(i)=23.8 nM), selectivity over 5-HT1A receptors (>50-fold), in vitro metabolic stability (82%) and weak interaction with P-glycoprotein (BA/AB=3.3). Compound 4b was injected ip in mice to preliminarily evaluate its distribution between blood and brain.

  5. N-benzylimidazole carboxamides as potent, orally active stearoylCoA desaturase-1 inhibitors.

    Science.gov (United States)

    Atkinson, Karen A; Beretta, Elena E; Brown, Janice A; Castrodad, Mayda; Chen, Yue; Cosgrove, Judith M; Du, Ping; Litchfield, John; Makowski, Michael; Martin, Kelly; McLellan, Thomas J; Neagu, Constantin; Perry, David A; Piotrowski, David W; Steppan, Claire M; Trilles, Richard

    2011-03-15

    A potent, small molecule inhibitor with a favorable pharmacokinetic profile to allow for sustained SCD inhibition in vivo was identified. Starting from a low MW acyl guanidine (5a), identified with a RapidFire High-Throughput Mass Spectrometry (RF-MS) assay, iterative library design was used to rapidly probe the amide and tail regions of the molecule. Singleton synthesis was used to probe core changes. Biological evaluation of a SCD inhibitor (5b) included in vitro potency at SCD-1 and in vivo modulation of the plasma desaturation index (DI) in rats on a low essential fatty acid (LEFA) diet. In addition to dose-dependent decrease in DI, effects on rodent ocular tissue were noted. Therefore, in rat, these SCD inhibitors only recapitulate a portion of phenotype exhibited by the SCD-1 knockout mouse. Copyright © 2011 Elsevier Ltd. All rights reserved.

  6. Sphingomyelinase D in sicariid spider venom is a potent insecticidal toxin.

    Science.gov (United States)

    Zobel-Thropp, Pamela A; Kerins, Alec E; Binford, Greta J

    2012-09-01

    Spider venoms have evolved over hundreds of millions of years with a primary role of immobilizing prey. Sphingomyelinase D (SMase D) and homologs in the SicTox gene family are the most abundantly expressed toxic protein in venoms of Loxosceles and Sicarius spiders (Sicariidae). While SMase D is well known to cause dermonecrotic lesions in mammals, little work has investigated the bioactivity of this enzyme in its presumed natural role of immobilizing insect prey. We expressed and purified recombinant SMase D from Loxosceles arizonica (Laz-SMase D) and compared its enzymatic and insecticidal activity to that of crude venom. SMase D enzymatic activities of purified protein and crude venom from the same species were indistinguishable. In addition, SMase D and crude venom have comparable and high potency in immobilization assays on crickets. These data indicate that SMase D is a potent insecticidal toxin, the role for which it presumably evolved.

  7. Design, synthesis and biological evaluation of novel bergapten derivatives as potent lipid lowering agents

    Directory of Open Access Journals (Sweden)

    Jian-Hong Lu

    2015-03-01

    Full Text Available The aim of this study was to synthesize novel amide derivatives of bergapten and evaluate their lipid-lowering and triglyceride-lowering activities in mice. Amide derivatives of bergapten were synthesized by using lactone ring opening strategy in DMSO using NaOH as base followed by alkylation in presence of methyl iodide. The compounds were subjected to preliminary in vivo screening. Fenofibrate (30 mg/kg/day was used as positive controls in this assay. The lipid lowering activity was evaluated using in vivo Triton model and Triton WR-1339 was used as positive control. Most of the synthesized analogs displayed remarkable plasma triglyceride-lowering activity. Compound 5 showed the best activity with (41% triglyceride lowering activity. This compound also exhibited the most potent lipid lowering activity displaying 33%, 32% and 29% lowering in total cholesterol, phospholipids, and triglycerides, respectively. The other derivatives showed almost comparable activity with that of the parent molecule.

  8. Novel GLP-1 fusion chimera as potent long acting GLP-1 receptor agonist.

    Directory of Open Access Journals (Sweden)

    Qinghua Wang

    Full Text Available GLP-1 has a variety of anti-diabetic effects. However, native GLP-1 is not suitable for therapy of diabetes due to its short half-life (t1/2168 h. Intraperitoneal glucose tolerance test (IPGTT in mice showed that GLP-1/hIgG2 significantly decreased glucose excursion. Furthermore, IPGTT performed on mice one week after a single drug-injection also displayed significantly reduced glucose excursion, indicating that GLP-1/hIgG2 fusion protein has long-lasting effects on the modulation of glucose homeostasis. GLP-1/hIgG2 was found to be effective in reducing the incidence of diabetes in multiple-low-dose streptozotocin-induced type 1 diabetes in mice. Together, the long-lasting bioactive GLP-1/hIgG2 retains native GLP-1 activities and thus may serve as a potent GLP-1 receptor agonist.

  9. A clinical observation of early short-term use of potent antibiotics in severely burned patients

    Institute of Scientific and Technical Information of China (English)

    RONG Xin-zhou; ZHANG Wen-zhen; REN Jia-liang; ZHOU Wei-ming

    2001-01-01

    Objective: To evaluate the effect of early and short-term use of potent antibiotics following extensive severe burn injury. Methods: Seventeen severely burned patients hospitalized in the same period (Nov.,1998 to Oct., 2000) wer esame treatment in Group 2 (n=8) was discontinued until day 15 postburn. The survival rate, blood bacterial culture, body temperature and white blood cell and platelet counts were compared between the 2 groups. Results: All the 17 patients survived and all blood bacterial cultures were negative. No significant difference of body temperature and white blood cell and platelet counts between the 2 groups was observed (P>0.05). Conclusion: Early use of high-potency antibiotics at short treatment course after extensive severe burn is effective to prevent infection and reduce the cost.

  10. Substituted fused bicyclic pyrrolizinones as potent, orally bioavailable hNK1 antagonists.

    Science.gov (United States)

    Morriello, Gregori J; Mills, Sander G; Johnson, Tricia; Reibarkh, Mikhail; Chicchi, Gary; DeMartino, Julie; Kurtz, Marc; Davies, P; Tsao, K L C; Zheng, Song; Tong, Xinchun; Carlson, Emma; Townson, Karen; Tattersall, F D; Wheeldon, Alan; Boyce, Susan; Collinson, Neil; Rupniak, Nadia; Moore, Stephen; DeVita, Robert J

    2010-03-15

    Previous work on human NK(1) (hNK(1)) antagonists in which the core of the structure is a 5,5-fused pyrrolizinone has been disclosed. The structural-activity-relationship studies on simple alpha- and beta-substituted compounds of this series provided several potent and bioavailable hNK(1) antagonists that displayed excellent brain penetration as observed by their good efficacy in the gerbil foot-tapping (GFT) model assay. Several of these compounds exhibited 100% inhibition of the foot-tapping response at 0.1 and 24h with ID(50)'s of less than 1 mpk. One particular alpha-substituted compound (2b) had an excellent pharmacokinetic profile across preclinical species with reasonable in vivo functional activity and minimal ancillary activity.

  11. Potent DGAT1 Inhibitors in the Benzimidazole Class with a Pyridyl-oxy-cyclohexanecarboxylic Acid Moiety.

    Science.gov (United States)

    He, Shuwen; Hong, Qingmei; Lai, Zhong; Wu, Zhicai; Yu, Yang; Kim, David W; Ting, Pauline C; Kuethe, Jeffrey T; Yang, Ginger X; Jian, Tianying; Liu, Jian; Guiadeen, Deodial; Krikorian, Arto D; Sperbeck, Donald M; Sonatore, Lisa M; Wiltsie, Judyann; Chung, Christine C; Gibson, Jack T; Lisnock, JeanMarie; Murphy, Beth A; Gorski, Judith N; Liu, Jinqi; Chen, Dunlu; Chen, Xiaoli; Wolff, Michael; Tong, Sharon X; Madeira, Maria; Karanam, Bindhu V; Shen, Dong-Ming; Balkovec, James M; Pinto, Shirly; Nargund, Ravi P; DeVita, Robert J

    2013-08-08

    We report the design and synthesis of a series of novel DGAT1 inhibitors in the benzimidazole class with a pyridyl-oxy-cyclohexanecarboxylic acid moiety. In particular, compound 11A is a potent DGAT1 inhibitor with excellent selectivity against ACAT1. Compound 11A significantly reduces triglyceride excursion in lipid tolerance tests (LTT) in both mice and dogs at low plasma exposure. An in vivo study in mice with des-fluoro analogue 10A indicates that this series of compounds appears to distribute in intestine preferentially over plasma. The propensity to target intestine over plasma could be advantageous in reducing potential side effects since lower circulating levels of drug are required for efficacy. However, in the preclinical species, compound 11A undergoes cis/trans epimerization in vivo, which could complicate further development due to the presence of an active metabolite.

  12. Sansanmycin natural product analogues as potent and selective anti-mycobacterials that inhibit lipid I biosynthesis

    Science.gov (United States)

    Tran, Anh T.; Watson, Emma E.; Pujari, Venugopal; Conroy, Trent; Dowman, Luke J.; Giltrap, Andrew M.; Pang, Angel; Wong, Weng Ruh; Linington, Roger G.; Mahapatra, Sebabrata; Saunders, Jessica; Charman, Susan A.; West, Nicholas P.; Bugg, Timothy D. H.; Tod, Julie; Dowson, Christopher G.; Roper, David I.; Crick, Dean C.; Britton, Warwick J.; Payne, Richard J.

    2017-03-01

    Tuberculosis (TB) is responsible for enormous global morbidity and mortality, and current treatment regimens rely on the use of drugs that have been in use for more than 40 years. Owing to widespread resistance to these therapies, new drugs are desperately needed to control the TB disease burden. Herein, we describe the rapid synthesis of analogues of the sansanmycin uridylpeptide natural products that represent promising new TB drug leads. The compounds exhibit potent and selective inhibition of Mycobacterium tuberculosis, the etiological agent of TB, both in vitro and intracellularly. The natural product analogues are nanomolar inhibitors of Mtb phospho-MurNAc-pentapeptide translocase, the enzyme responsible for the synthesis of lipid I in mycobacteria. This work lays the foundation for the development of uridylpeptide natural product analogues as new TB drug candidates that operate through the inhibition of peptidoglycan biosynthesis.

  13. A novel bispecific antibody, S-Fab, induces potent cancer cell killing.

    Science.gov (United States)

    Li, Li; He, Ping; Zhou, Changhua; Jing, Li; Dong, Bin; Chen, Siqi; Zhang, Ning; Liu, Yawei; Miao, Ji; Wang, Zhong; Li, Qing

    2015-01-01

    Bispecific antibodies that engage immune cells to kill cancer cells have been actively studied in cancer immunotherapy. In this study, we present a novel bispecific format, S-Fab, fabricated by linking a single-domain anti-carcinoembryonic antigen VHH to a conventional anti-CD3 Fab. In contrast to most bispecific antibodies, the S-Fab bispecific antibody can be efficiently expressed and purified from bacteria. The purified S-Fab is stable in serum and is able to recruit T cells to drive potent cancer cell killing. In xenograft models, the S-Fab antibody suppresses tumor growth in the presence of human immune cells. Our study suggested that the bispecific S-Fab format can be applied to a wide range of immunotherapies.

  14. Synthesis of novel disulfide and sulfone hybrid scaffolds as potent β-glucuronidase inhibitor.

    Science.gov (United States)

    Taha, Muhammad; Ismail, Nor Hadiani; Imran, Syahrul; Wadood, Abdul; Rahim, Fazal; Al Muqarrabin, Laode Muhammad Ramadhan; Zaki, Hamizah Mohd; Ahmat, Norizan; Nasir, Abdul; Khan, Fahad

    2016-10-01

    Novel series of disulfide and sulfone hybrid analogs (1-20) were synthesized and characterized through EI-MS and (1)H NMR and evaluated for β-glucuronidase inhibitory potential. All synthesized analogs except 13 and 15 showed excellent β-glucuronidase inhibitory potential with IC50 value ranging in between 2.20-88.16μM as compared to standard d-saccharic acid 1,4 lactone (48.4±1.25μM). Analogs 19, 16, 4, 1, 17, 6, 10, 3, 18, 2, 11, 14 and 5 showed many fold potent activity against β-glucuronidase inhibitor. Structure activity relationship showed that substitution of electron withdrawing groups at ortho as well as para position on phenyl ring increase potency. Electron withdrawing groups at meta position on phenyl ring showed slightly low potency as compared to ortho and para position. The binding interactions were confirmed through molecular docking studies.

  15. Demethoxycurcumin is a potent inhibitor of P-type ATPases from diverse kingdoms of life

    DEFF Research Database (Denmark)

    Dao, Trong Tuan; Sehgal, Pankaj; Thanh Tung, Truong;

    2016-01-01

    the curcuminoids, demethoxycurcumin was the most potent inhibitor of all tested P-type ATPases from fungal (Pma1p; H+-ATPase), plant (AHA2; H+-ATPase) and animal (SERCA; Ca2+-ATPase) cells. All three curcuminoids acted as non-competitive antagonist to ATP and hence may bind to a highly conserved allosteric site......P-type ATPases catalyze the active transport of cations and phospholipids across biological membranes. Members of this large family are involved in a range of fundamental cellular processes. To date, a substantial number of P-type ATPase inhibitors have been characterized, some of which are used...... as drugs. In this work a library of natural compounds was screened and we first identified curcuminoids as plasma membrane H+-ATPases inhibitors in plant and fungal cells. We also found that some of the commercial curcumins contain several curcuminoids. Three of these were purified and, among...

  16. Alkamides from the fruits of Piper longum and Piper nigrum displaying potent cell adhesion inhibition.

    Science.gov (United States)

    Lee, Seung Woong; Kim, Young Kook; Kim, Koanhoi; Lee, Hyun Sun; Choi, Jung Ho; Lee, Woo Song; Jun, Chang-Duk; Park, Jee Hun; Lee, Jeong Min; Rho, Mun-Chual

    2008-08-15

    Eight alkamides 1-8 were isolated by bioassay-guided isolation of EtOH extracts of the fruits of Piper longum and Piper nigum (Piperaceae). Their structures were elucidated by spectroscopic analysis ((1)H, (13)C NMR, and ESI-MS) as follows: guineensine (1), retrofracamide C (2), (2E,4Z,8E)-N-[9-(3,4-methylenedioxyphenyl)-2,4,8-nonatrienoyl]piperidine (3), pipernonaline (4), piperrolein B (5), piperchabamide D (6), pellitorin (7), and dehydropipernonaline (8). Their compounds 3-5, 7, and 8 inhibited potently the direct binding between sICAM-1 and LFA-1 of THP-1 cells in a dose-dependent manner, with IC(50) values of 10.7, 8.8, 13.4, 13.5, and 6.0 microg/mL, respectively.

  17. High-speed helicopter rotor noise - Shock waves as a potent source of sound

    Science.gov (United States)

    Farassat, F.; Lee, Yung-Jang; Tadghighi, H.; Holz, R.

    1991-01-01

    In this paper we discuss the problem of high speed rotor noise prediction. In particular, we propose that from the point of view of the acoustic analogy, shocks around rotating blades are sources of sound. We show that, although for a wing at uniform steady rectilinear motion with shocks the volume quadrupole and shock sources cancel in the far field to the order of 1/r, this cannot happen for rotating blades. In this case, some cancellation between volume quadrupoles and shock sources occurs, yet the remaining shock noise contribution is still potent. A formula for shock noise prediction is presented based on mapping the deformable shock surface to a time independent region. The resulting equation is similar to Formulation 1A of Langley. Shock noise prediction for a hovering model rotor for which experimental noise data exist is presented. The comparison of measured and predicted acoustic data shows good agreement.

  18. Isolation of potent neutralizing antibodies from a survivor of the 2014 Ebola virus outbreak.

    Science.gov (United States)

    Bornholdt, Zachary A; Turner, Hannah L; Murin, Charles D; Li, Wen; Sok, Devin; Souders, Colby A; Piper, Ashley E; Goff, Arthur; Shamblin, Joshua D; Wollen, Suzanne E; Sprague, Thomas R; Fusco, Marnie L; Pommert, Kathleen B J; Cavacini, Lisa A; Smith, Heidi L; Klempner, Mark; Reimann, Keith A; Krauland, Eric; Gerngross, Tillman U; Wittrup, Karl D; Saphire, Erica Ollmann; Burton, Dennis R; Glass, Pamela J; Ward, Andrew B; Walker, Laura M

    2016-03-01

    Antibodies targeting the Ebola virus surface glycoprotein (EBOV GP) are implicated in protection against lethal disease, but the characteristics of the human antibody response to EBOV GP remain poorly understood. We isolated and characterized 349 GP-specific monoclonal antibodies (mAbs) from the peripheral B cells of a convalescent donor who survived the 2014 EBOV Zaire outbreak. Remarkably, 77% of the mAbs neutralize live EBOV, and several mAbs exhibit unprecedented potency. Structures of selected mAbs in complex with GP reveal a site of vulnerability located in the GP stalk region proximal to the viral membrane. Neutralizing antibodies targeting this site show potent therapeutic efficacy against lethal EBOV challenge in mice. The results provide a framework for the design of new EBOV vaccine candidates and immunotherapies.

  19. Potent single-domain antibodies that arrest respiratory syncytial virus fusion protein in its prefusion state

    Science.gov (United States)

    Rossey, Iebe; Gilman, Morgan S. A.; Kabeche, Stephanie C.; Sedeyn, Koen; Wrapp, Daniel; Kanekiyo, Masaru; Chen, Man; Mas, Vicente; Spitaels, Jan; Melero, José A.; Graham, Barney S.; Schepens, Bert; McLellan, Jason S.; Saelens, Xavier

    2017-01-01

    Human respiratory syncytial virus (RSV) is the main cause of lower respiratory tract infections in young children. The RSV fusion protein (F) is highly conserved and is the only viral membrane protein that is essential for infection. The prefusion conformation of RSV F is considered the most relevant target for antiviral strategies because it is the fusion-competent form of the protein and the primary target of neutralizing activity present in human serum. Here, we describe two llama-derived single-domain antibodies (VHHs) that have potent RSV-neutralizing activity and bind selectively to prefusion RSV F with picomolar affinity. Crystal structures of these VHHs in complex with prefusion F show that they recognize a conserved cavity formed by two F protomers. In addition, the VHHs prevent RSV replication and lung infiltration of inflammatory monocytes and T cells in RSV-challenged mice. These prefusion F-specific VHHs represent promising antiviral agents against RSV. PMID:28194013

  20. Microwave Assisted Synthesis of Novel Imidazolopyridinyl Indoles as Potent Antioxidant and Antimicrobial Agents

    Directory of Open Access Journals (Sweden)

    Jaiprakash S. Biradar

    2014-01-01

    Full Text Available We describe herein the design, synthesis, and pharmacological evaluation of novel series of imidazolopyridinyl indole analogues as potent antioxidants and antimicrobials. These novel compounds (3a–i were synthesized by reacting 3,5-disubstituted-indole-2-carboxylic acid (1a–i with 2,3-diamino pyridine (2 in excellent yield. The novel products were confirmed by their IR, 1H NMR, 13C NMR, mass spectral, and analytical data. These compounds were screened for their antioxidant and antimicrobial activities. Among the compounds tested, 3a–d showed the highest total antioxidant capacity, scavenging, and antimicrobial activities. Compounds 3c-d and 3g-h have shown excellent ferric reducing activity.

  1. Current Advances in Antitubercular Drug Discovery: Potent Prototypes and New Targets.

    Science.gov (United States)

    Dos Santos Fernandes, Guilherme Felipe; Jornada, Daniela Hartmann; de Souza, Paula Carolina; Chin, Chung Man; Pavan, Fernando Rogerio; Dos Santos, Jean Leandro

    2015-01-01

    Tuberculosis (TB) is an infectious disease caused by bacterium of the Mycobacterium genus, mainly by Mycobacterium tuberculosis (MTB). The World Health Organization aims to substantially reduce the number of cases in the coming years; however, the increased number of multidrug-resistant (MDR) and extremely drug-resistant (XDR) forms of the bacterium and the lack of treatment for latent tuberculosis are challenges to be overcome. In this review, we have identified the most potent compounds described in the literature during recent years with MIC values < 7 µM, low toxicity and a high selective index. In addition, emerging targets in MTB are presented to provide new perspectives for the discovery of new antitubercular drugs. This review aims to summarize the current advances in and promote insights into antitubercular drug discovery.

  2. Evaluation of NHS carbamates as a potent and selective class of endocannabinoid hydrolase inhibitors.

    Science.gov (United States)

    Niphakis, Micah J; Cognetta, Armand B; Chang, Jae Won; Buczynski, Matthew W; Parsons, Loren H; Byrne, Frederika; Burston, James J; Chapman, Victoria; Cravatt, Benjamin F

    2013-09-18

    Monoacylglycerol lipase (MAGL) is a principal metabolic enzyme responsible for hydrolyzing the endogenous cannabinoid (endocannabinoid) 2-arachidonoylglycerol (2-AG). Selective inhibitors of MAGL offer valuable probes to further understand the enzyme's function in biological systems and may lead to drugs for treating a variety of diseases, including psychiatric disorders, neuroinflammation, and pain. N-Hydroxysuccinimidyl (NHS) carbamates have recently been identified as a promising class of serine hydrolase inhibitors that shows minimal cross-reactivity with other proteins in the proteome. Here, we explore NHS carbamates more broadly and demonstrate their potential as inhibitors of endocannabinoid hydrolases and additional enzymes from the serine hydrolase class. We extensively characterize an NHS carbamate 1a (MJN110) as a potent, selective, and in-vivo-active MAGL inhibitor. Finally, we demonstrate that MJN110 alleviates mechanical allodynia in a rat model of diabetic neuropathy, marking NHS carbamates as a promising class of MAGL inhibitors.

  3. Doxepin Has a Potent and Long-Acting Spinal Anesthetic Effect in Rats

    Directory of Open Access Journals (Sweden)

    Bor-Chin Cheng

    2006-02-01

    Full Text Available Doxepin, a tricyclic antidepressant, was recently found to be effective in the treatment of various acute and chronic painful conditions. However, the mechanism of its actions was not clear, especially when involving the spine. The aim of our study was to evaluate the spinal anesthetic effect of doxepin. Two commonly used traditional local anesthetics, bupivacaine and lidocaine, were used as controls. The potencies and durations of the drugs' action were evaluated in male Sprague-Dawley rats. We found that intrathecally administered doxepin, like bupivacaine and lidocaine, produced dose-related spinal anesthetic effects on motor activity, proprioception, and nociception. Among the three drugs, doxepin produced spinal anesthetic effects in rats more potent than that of lidocaine (p < 0.001, in each comparison and longer than that of bupivacaine and lidocaine (p < 0.001, in each comparison. The spinal activity of doxepin may provide some explanation of its clinical effect in pain management.

  4. Chemoproteomics-Enabled Discovery of a Potent and Selective Inhibitor of the DNA Repair Protein MGMT.

    Science.gov (United States)

    Wang, Chao; Abegg, Daniel; Hoch, Dominic G; Adibekian, Alexander

    2016-02-18

    We present a novel chemical scaffold for cysteine-reactive covalent inhibitors. Chloromethyl triazoles (CMTs) are readily accessed in only two chemical steps, thus enabling the rapid optimization of the pharmacological properties of these inhibitors. We demonstrate the tunability of the CMTs towards a specific biological target by synthesizing AA-CW236 as the first potent non-pseudosubstrate inhibitor of the O(6) -alkylguanine DNA methyltransferase (MGMT), a protein of major clinical significance for the treatment of several severe cancer forms. Using quantitative proteomics profiling techniques, we show that AA-CW236 exhibits a high degree of selectivity towards MGMT. Finally, we validate the effectiveness of our MGMT inhibitor in combination with the DNA alkylating drug temozolomide in breast and colon cancer cells by fluorescence imaging and a cell-viability assay. Our results may open a new avenue towards the development of a clinically approved MGMT inhibitor.

  5. Structure-based redesign of lysostaphin yields potent antistaphylococcal enzymes that evade immune cell surveillance.

    Science.gov (United States)

    Blazanovic, Kristina; Zhao, Hongliang; Choi, Yoonjoo; Li, Wen; Salvat, Regina S; Osipovitch, Daniel C; Fields, Jennifer; Moise, Leonard; Berwin, Brent L; Fiering, Steven N; Bailey-Kellogg, Chris; Griswold, Karl E

    2015-01-01

    Staphylococcus aureus infections exert a tremendous burden on the health-care system, and the threat of drug-resistant strains continues to grow. The bacteriolytic enzyme lysostaphin is a potent antistaphylococcal agent with proven efficacy against both drug-sensitive and drug-resistant strains; however, the enzyme's own bacterial origins cause undesirable immunogenicity and pose a barrier to clinical translation. Here, we deimmunized lysostaphin using a computationally guided process that optimizes sets of mutations to delete immunogenic T cell epitopes without disrupting protein function. In vitro analyses showed the methods to be both efficient and effective, producing seven different deimmunized designs exhibiting high function and reduced immunogenic potential. Two deimmunized candidates elicited greatly suppressed proliferative responses in splenocytes from humanized mice, while at the same time the variants maintained wild-type efficacy in a staphylococcal pneumonia model. Overall, the deimmunized enzymes represent promising leads in the battle against S. aureus.

  6. Attraction and activation of dendritic cells at the site of tumor elicits potent antitumor immunity.

    Science.gov (United States)

    Lapteva, Natalia; Aldrich, Melissa; Rollins, Lisa; Ren, Wenhong; Goltsova, Tatiana; Chen, Si-Yi; Huang, Xue F

    2009-09-01

    Tumor cells harbor unique genetic mutations, which lead to the generation of immunologically foreign antigenic peptide repertoire with the potential to induce individual tumor-specific immune responses. Here, we developed an in situ tumor vaccine with the ability to elicit antitumor immunity. This vaccine comprised an E1B-deleted oncolytic adenovirus expressing beta-defensin-2 (Ad-BD2-E1A) for releasing tumor antigens, recruiting and activating plasmacytoid dendritic cells (pDCs). Intratumoral injections of Ad-BD2-E1A vaccine inhibited primary breast tumor growth and blocked naturally occurring metastasis in mice. Ad-BD2-E1A vaccination induced potent tumor-specific T-cell responses. Splenic and intratumoral DCs isolated from Ad-BD2-E1A-immunized mice were able to stimulate or promote the differentiation of naive T cells into tumor-specific cytotoxic T cells. We further found that the increased numbers of mature CD45RA(+)CD8alpha(+)CD40(+) pDCs infiltrated into Ad-BD2-E1A-treated tumors. The antitumor effect of Ad-BD2-E1A vaccination was abrogated in toll-like receptor 4 (TLR4) deficient mice, suggesting the critical role of TLR4 in the induction of antitumor immunity by Ad-BD2-E1A. The results of this study indicate that in situ vaccination with the oncolytic BD2-expressing adenovirus preferentially attracts pDCs and promotes their maturation, and thus elicits potent tumor-specific immunity. This vaccine represents an attractive therapeutic strategy for the induction of individualized antitumor immunity.

  7. Placental growth factor is a potent vasodilator of rat and human resistance arteries.

    Science.gov (United States)

    Osol, George; Celia, Gerard; Gokina, Natalia; Barron, Carolyn; Chien, Edward; Mandala, Maurizio; Luksha, Leonid; Kublickiene, Karolina

    2008-03-01

    The objectives of this study were to determine whether placental growth factor (PlGF) exerts a vasodilatory effect on rat uterine vessels (arcuate arteries and veins) and to examine regional differences in reactivity by comparing these responses to those of comparably sized mesenteric vessels. We also sought to examine and compare its effects on human uterine and subcutaneous vessels. All vessels were studied in vitro, under pressurized (rat) or isometric wire-mounted (human) conditions, and exposed to a range of PlGF concentrations. Inhibitors of nitric oxide and prostaglandin synthesis were included in an effort to understand the causal mechanism(s). In rat uterine arteries, the effects of receptor inhibition and activation using selective ligands for VEGFR-1 (PlGF) vs. VEGFR-2 (VEGF-E) were determined, and real-time RT-PCR was performed to evaluate the effect of pregnancy on relative abundance of VEGFR-1 and VEGFR-2 message in the vascular wall. PlGF was a potent vasodilator of all vessels studied, with greatest sensitivity observed in rat uterine arteries. Pregnancy significantly augmented dilator sensitivity to PlGF, and this effect was associated with selective upregulation of VEGFR-1 message in the pregnant state. The contribution of nitric oxide was appreciable in rat and human uterine arteries, with lesser effects in rat uterine veins and mesenteric arteries, and with no observable effect in human subcutaneous vessels. Based on these results, we conclude that PlGF is a potent vasodilator of several vessel types in both humans and rats. Its potency and mechanism vary with physiological state and vessel location and are mediated solely by the VEGFR-1 receptor subtype. Gestational changes in the uterine circulation suggest that this factor may play a role in modulating uterine vascular remodeling and blood flow during the pregnant state.

  8. PLACENTAL GROWTH FACTOR (PlGF) IS A POTENT VASODILATOR OF RAT AND HUMAN RESISTANCE ARTERIES

    Science.gov (United States)

    Osol, George; Celia, Gerard; Gokina, Natalia; Barron, Carolyn; Chien, Edward; Mandala, Maurizio; Luksha, Leonid; Kublickiene, Karolina

    2010-01-01

    The objectives of this study were to determine whether PlGF exerts a vasodilatory effect on rat uterine vessels (arcuate arteries and veins) and to examine regional differences in reactivity by comparing these responses to those of comparably-sized mesenteric vessels. We also sought to examine and compare its effects on human uterine and subcutaneous vessels. All vessels were studied in vitro, under pressurized (rat) or isometric wire-mounted (human) conditions, and exposed to a range of PlGF concentrations. Inhibitors of nitric oxide and prostaglandin synthesis were included in an effort to understand the causal mechanism(s). In rat uterine arteries, the effects of receptor inhibition and activation using selective ligands for VEGFR-1 (PlGF) vs. VEGFR-2 (VEGF-E) were determined, and real-time RT-PCR was performed to evaluate the effect of pregnancy on relative abundance of VEGFR-1 and VEGFR-2 message in the vascular wall. PlGF was a potent vasodilator of all vessels studied, with greatest sensitivity observed in rat uterine arteries. Pregnancy significantly augmented dilator sensitivity to PlGF, and this effect was associated with selective upregulation of VEGFR-1 message in the pregnant state. The contribution of nitric oxide was appreciable in rat and human uterine arteries, with lesser effects in rat uterine veins and mesenteric arteries, and with no observable effect in human subcutaneous vessels. Based on these results, we conclude that PlGF is a potent vasodilator of several vessel types in both humans and rats. Its potency and mechanism varies with physiological state and vessel location, and is mediated solely by the VEGFR-1 receptor subtype. Gestational changes in the uterine circulation suggest that this factor may play a role in modulating uterine vascular remodeling and blood flow during the pregnant state. PMID:18192215

  9. Discovery and Characterization of a Potent Interleukin-6 Binding Peptide with Neutralizing Activity In Vivo

    Science.gov (United States)

    Ranganath, Sheila; Bhandari, Ashok; Avitahl-Curtis, Nicole; McMahon, Jaimee; Wachtel, Derek; Zhang, Jenny; Leitheiser, Christopher; Bernier, Sylvie G.; Liu, Guang; Tran, Tran T.; Celino, Herodion; Tobin, Jenny; Jung, Joon; Zhao, Hong; Glen, Katie E.; Graul, Chris; Griffin, Aliesha; Schairer, Wayne C.; Higgins, Carolyn; Reza, Tammi L.; Mowe, Eva; Rivers, Sam; Scott, Sonya; Monreal, Alex; Shea, Courtney; Bourne, Greg; Coons, Casey; Smith, Adaline; Tang, Kim; Mandyam, Ramya A.; Masferrer, Jaime; Liu, David; Patel, Dinesh V.; Fretzen, Angelika; Murphy, Craig A.; Milne, G. Todd; Smythe, Mark L.; Carlson, Kenneth E.

    2015-01-01

    Interleukin-6 (IL-6) is an important member of the cytokine superfamily, exerting pleiotropic actions on many physiological processes. Over-production of IL-6 is a hallmark of immune-mediated inflammatory diseases such as Castleman’s Disease (CD) and rheumatoid arthritis (RA). Antagonism of the interleukin IL-6/IL-6 receptor (IL-6R)/gp130 signaling complex continues to show promise as a therapeutic target. Monoclonal antibodies (mAbs) directed against components of this complex have been approved as therapeutics for both CD and RA. To potentially provide an additional modality to antagonize IL-6 induced pathophysiology, a peptide-based antagonist approach was undertaken. Using a combination of molecular design, phage-display, and medicinal chemistry, disulfide-rich peptides (DRPs) directed against IL-6 were developed with low nanomolar potency in inhibiting IL-6-induced pSTAT3 in U937 monocytic cells. Targeted PEGylation of IL-6 binding peptides resulted in molecules that retained their potency against IL-6 and had a prolongation of their pharmacokinetic (PK) profiles in rodents and monkeys. One such peptide, PN-2921, contained a 40 kDa polyethylene glycol (PEG) moiety and inhibited IL-6-induced pSTAT3 in U937 cells with sub-nM potency and possessed 23, 36, and 59 h PK half-life values in mice, rats, and cynomolgus monkeys, respectively. Parenteral administration of PN-2921 to mice and cynomolgus monkeys potently inhibited IL-6-induced biomarker responses, with significant reductions in the acute inflammatory phase proteins, serum amyloid A (SAA) and C-reactive protein (CRP). This potent, PEGylated IL-6 binding peptide offers a new approach to antagonize IL-6-induced signaling and associated pathophysiology. PMID:26555695

  10. 7-Chloroarctinone-b as a new selective PPARγ antagonist potently blocks adipocyte differentiation

    Institute of Scientific and Technical Information of China (English)

    Yong-tao LI; Li LI; Jing CHEN; Tian-cen HU; Jin HUANG; Yue-wei GUO; Hua-liang JIANG; Xu SHEN

    2009-01-01

    Aim: Peroxisome proliferator-activated receptor gamma (PPARy) is a therapeutic target for obesity, cancer and diabetes mellitus. In order to develop potent lead compounds for obesity treatment, we screened a natural product library for novel PPARy antagonists with inhibitory effects on adipocyte differentiation. Methods: Surface plasmon resonance (SPR) technology and cell-based transactivation assay were used to screen for PPARy antago-nists. To investigate the antagonistic mechanism of the active compound, we measured its effect on PPARy/RXRα heterodimerization and PPARy co-activator recruitment using yeast two-hybrid assay, Gal4/UAS cell-based assay and SPR based assay. The 3T3-L1 cell differentiation assay was used to evaluate the effect of the active compound on adipocyte differentiation. Results: A new thiophene-acetylene type of natural product, 7-chloroarctinone-b (CAB), isolated from the roots of Rhaponticum uniflo-rum, was discovered as a novel PPARγ antagonist capable of inhibiting rosiglitazone-induced PPARγ transcriptional activity. SPR analy-sis suggested that CAB bound tightly to PPARγ and considerably antagonized the potent PPARy agonist rosigtitazone-stimulated PPARγ-LBD/RXRα-LBD binding. Gal4/UAS and yeast two-hybrid assays were used to evaluate the antagonistic activity of CAB on rosiglitazone-induced recruitment of the coactivator for PPARy. CAB could efficiently antagonize both hormone and rosiglitazone-induced adipocyte differentiation in cell culture. Conclusion: CAB shows antagonistic activity to PPARγ and can block the adipocyte differentiation, indicating it may be of potential use as a lead therapeutic compound for obesity.

  11. Binding ability of impromidine, a potent H2 agonist of histamine

    Science.gov (United States)

    Anouar, A.; Lhadi, E.; Decock, P.; Kozlowskyinst4, H.

    1999-09-01

    Impromidine (fig.1) is a potent and selective histamine H2 receptor agonist and its structure comprises a strongly basic guanidine group containing two different imidazole-containing side chains. The present work deals with the study of coordination equilibria between impromidine and Cu(II) and Ni(II) in aqueous solution at 25 circC. Potentiometric, UV-Visible and EPR studies on Cu(II) complexes with impromidine have shown that this anti-ulcerogenic drug is a very potent chelating agent. This drug is found to be a very effective ligand for Ni(II) ions also. The effective coordination of impromidine to metal ions may have significant biological implications. L'impromidine est un agoniste H2 de l'histamine, sa structure possède un groupement guanidinique de forte basicité et dont l'environne ment des deux groupements imidazoliques est différent. Le présent travail consiste en l'étude de la coordination de l'impromidine avec le Cu(II) et le Ni(II) en milieu aqueux à 25 circC. La potentiométrie, LíUV-Visible et la RPE montrent que le cuivre se coordine très fortement avec l'impromidine. Nous avons trouvé que ce médicament se coordine aussi fortement avec le nickel(II). La coordination de l'impromidine avec les métaux pourrait avoir des applications importantes en médecine.

  12. Triclosan Derivatives: Towards Potent Inhibitors of Drug-Sensitive and Drug-Resistant Mycobacterium tuberculosis

    Energy Technology Data Exchange (ETDEWEB)

    Freundlich, Joel S.; Wang, Feng; Vilchèze, Catherine; Gulten, Gulcin; Langley, Robert; Schiehser, Guy A.; Jacobus, David P.; Jacobs, Jr., William R.; Sacchettini, James C.; (Einstein); (TAM); (Jacobus)

    2009-06-30

    Isoniazid (INH) is a frontline antitubercular drug that inhibits the enoyl acyl carrier protein reductase InhA. Novel inhibitors of InhA that are not cross-resistant to INH represent a significant goal in antitubercular chemotherapy. The design, synthesis, and biological activity of a series of triclosan-based inhibitors is reported, including their promising efficacy against INH-resistant strains of M. tuberculosis. Triclosan has been previously shown to inhibit InhA, an essential enoyl acyl carrier protein reductase involved in mycolic acid biosynthesis, the inhibition of which leads to the lysis of Mycobacterium tuberculosis. Using a structure-based drug design approach, a series of 5-substituted triclosan derivatives was developed. Two groups of derivatives with alkyl and aryl substituents, respectively, were identified with dramatically enhanced potency against purified InhA. The most efficacious inhibitor displayed an IC{sub 50} value of 21 nM, which was 50-fold more potent than triclosan. X-ray crystal structures of InhA in complex with four triclosan derivatives revealed the structural basis for the inhibitory activity. Six selected triclosan derivatives were tested against isoniazid-sensitive and resistant strains of M. tuberculosis. Among those, the best inhibitor had an MIC value of 4.7 {mu}g mL{sup -1} (13 {mu}M), which represents a tenfold improvement over the bacteriocidal activity of triclosan. A subset of these triclosan analogues was more potent than isoniazid against two isoniazid-resistant M. tuberculosis strains, demonstrating the significant potential for structure-based design in the development of next generation antitubercular drugs.

  13. Recent advances in the development of 14-alkoxy substituted morphinans as potent and safer opioid analgesics.

    Science.gov (United States)

    Spetea, M; Schmidhammer, H

    2012-01-01

    Morphine and other opioid morphinans produce analgesia primarily through μ opioid receptors (MORs), which mediate beneficial but also non-beneficial actions. There is a continued search for efficacious opioid analgesics with reduced complications. The cornerstone in the development of 14-alkoxymorphinans as novel analgesic drugs was the synthesis of the highly potent MOR agonist 14-O-methyloxymorphone. This opioid showed high antinociceptive potency but also the adverse effects associated with morphine type compounds. Further developments represent the introduction of a methyl and benzyl group at position 5 of 14-O-methyloxymorphone leading to the strong opioid analgesics 14-methoxymetopon and its 5-benzyl analogue, which exhibited less pronounced side effects than morphine although interacting selectively with MORs. Introduction of arylalkyl substituents such as phenylpropoxy in position 14 led to a series of extremely potent antinociceptive agents with enhanced affinities at all three opioid receptor types. During the past years, medicinal chemistry and opioid research focused increasingly on exploring the therapeutic potential of peripheral opioid receptors by peripheralization of opioids in order to minimize the occurrence of centrally-mediated side effects. Strategies to reduce penetration to the central nervous system (CNS) include chemical modifications that increase hydrophilicity. Zwitterionic 6-amino acid conjugates of 14-Oalkyloxymorphones were developed in an effort to obtain opioid agonists that have limited access to the CNS. These compounds show high antinociceptive potency by interacting with peripheral MORs. Opioid drugs with peripheral site of action represent an important target for the treatment of severe and chronic pain without the adverse actions of centrally acting opioids.

  14. Molecular docking simulation studies on potent butyrylcholinesterase inhibitors obtained from microbial transformation of dihydrotestosterone

    Science.gov (United States)

    2013-01-01

    Background Biotransformation is an effective technique for the synthesis of libraries of bioactive compounds. Current study on microbial transformation of dihydrotestosterone (DHT) (1) was carried out to produce various functionalized metabolites. Results Microbial transformation of DHT (1) by using two fungal cultures resulted in potent butyrylcholinesterase (BChE) inhibitors. Biotransformation with Macrophomina phaseolina led to the formation of two known products, 5α-androstan-3β,17β-diol (2), and 5β-androstan-3α,17β-diol (3), while biotransformation with Gibberella fujikuroi yielded six known metabolites, 11α,17β-dihydroxyandrost-4-en-3-one (4), androst-1,4-dien-3,17-dione (5), 11α-hydroxyandrost-4-en-3,17-dione (6), 11α-hydroxyandrost-1,4-dien-3,17-dione (7), 12β-hydroxyandrost-1,4-dien-3,17-dione (8), and 16α-hydroxyandrost-1,4-dien-3,17-dione (9). Metabolites 2 and 3 were found to be inactive, while metabolite 4 only weakly inhibited the enzyme. Metabolites 5–7 were identified as significant inhibitors of BChE. Furthermore, predicted results from docking simulation studies were in complete agreement with experimental data. Theoretical results were found to be helpful in explaining the possible mode of action of these newly discovered potent BChE inhibitors. Compounds 8 and 9 were not evaluated for enzyme inhibition activity both in vitro and in silico, due to lack of sufficient quantities. Conclusion Biotransformation of DHT (1) with two fungal cultures produced eight known metabolites. Metabolites 5–7 effectively inhibited the BChE activity. Cholinesterase inhibition is among the key strategies in the management of Alzheimer’s disease (AD). The experimental findings were further validated by in silico inhibition studies and possible modes of action were deduced. PMID:24103815

  15. TCIQ: An identification by intensity and frequency of potent testing cues in science

    Science.gov (United States)

    Kermis, William J.

    Everyone experiences some anxiety while taking an examination. High-test-anxious (HTA) and low-test-anxious (LTA) students are described by two characteristic differences: frequency and intensity of anxious responses and attentional direction to testing cues. The purposes of this study were threefold: (1) to report potent testing cues (i.e., 90% response agreement for both intensity and frequency) that were identified by HTA and LTA students; (2) to report differences between HTA and LTA students for frequencies and intensities of responses to testing cues; and (3) to report differences between HTA and LTA students of attentional direction to testing cues. A pool of 396 males and females who were enrolled in physical geology completed the State-Trait Anxiety Inventory. A random sample consisting of 93 HTA and 40 LTA subjects completed the Test Cues Identification Questionnaire (TCIQ). The TCIQ consists of 28 disruptive items and 27 helpful items. Subjects responded with both frequency and intensity ratings for all of the 55 items in the TCIQ. Results revealed that 22 items were viewed by subjects as potent testing cues. Empirical evidence obtained did not support previous theoretical reports of differences between HTA and LTA students for either frequency and intensity of anxious responses or attentional direction to the set of disruptive and helpful testing cues. Although test anxiousness did not appear to be associated with those two characteristics differences, a discriminant analysis revealed 24 items in the TCIQ which significantly, 2 (24) = 47.59, p separated HTA and LTA subjects responses. Apparently, HTA and LTA students differ in their responses to specific disruptive and helpful cues but not in their responses to the set of testing cues as was previously postulated.

  16. The Second-Generation Exportin-1 Inhibitor KPT-8602 Demonstrates Potent Activity against Acute Lymphoblastic Leukemia.

    Science.gov (United States)

    Vercruysse, Thomas; De Bie, Jolien; Neggers, Jasper E; Jacquemyn, Maarten; Vanstreels, Els; Schmid-Burgk, Jonathan L; Hornung, Veit; Baloglu, Erkan; Landesman, Yosef; Senapedis, William; Shacham, Sharon; Dagklis, Antonis; Cools, Jan; Daelemans, Dirk

    2016-10-25

    Purpose: Human exportin-1 (XPO1) is the key nuclear-cytoplasmic transport protein that exports different cargo proteins out of the nucleus. Inducing nuclear accumulation of these proteins by inhibiting XPO1 causes cancer cell death. First clinical validation of pharmacological inhibition of XPO1 was obtained with the Selective Inhibitor of Nuclear Export (SINE) compound selinexor (KPT-330) demonstrating activity in phase-II/IIb clinical trials when dosed 1 to 3 times weekly. The second-generation SINE compound KPT-8602 shows improved tolerability and can be dosed daily. Here, we investigate and validate the drug-target interaction of KPT-8602 and explore its activity against acute lymphoblastic leukemia (ALL).Experimental Design: We examined the effect of KPT-8602 on XPO1 function and XPO1-cargo as well as on a panel of leukemia cell lines. Mutant XPO1 leukemia cells were designed to validate KPT-8602's drug-target interaction. In vivo, anti-ALL activity was measured in a mouse ALL model and patient-derived ALL xenograft models.Results: KPT-8602 induced caspase-dependent apoptosis in a panel of leukemic cell lines in vitro Using CRISPR/Cas9 genome editing, we demonstrated the specificity of KPT-8602 for cysteine 528 in the cargo-binding groove of XPO1 and validated the drug target interaction. In vivo, KPT-8602 showed potent anti-leukemia activity in a mouse ALL model as well as in patient-derived T- and B-ALL xenograft models without affecting normal hematopoiesis.Conclusions: KPT-8602 is highly specific for XPO1 inhibition and demonstrates potent anti-leukemic activity supporting clinical application of the second-generation SINE compound for the treatment of ALL. Clin Cancer Res; 1-14. ©2016 AACR.

  17. Building a better dynasore: the dyngo compounds potently inhibit dynamin and endocytosis.

    Science.gov (United States)

    McCluskey, Adam; Daniel, James A; Hadzic, Gordana; Chau, Ngoc; Clayton, Emma L; Mariana, Anna; Whiting, Ainslie; Gorgani, Nick N; Lloyd, Jonathan; Quan, Annie; Moshkanbaryans, Lia; Krishnan, Sai; Perera, Swetha; Chircop, Megan; von Kleist, Lisa; McGeachie, Andrew B; Howes, Mark T; Parton, Robert G; Campbell, Michael; Sakoff, Jennette A; Wang, Xuefeng; Sun, Jian-Yuan; Robertson, Mark J; Deane, Fiona M; Nguyen, Tam H; Meunier, Frederic A; Cousin, Michael A; Robinson, Phillip J

    2013-12-01

    Dynamin GTPase activity increases when it oligomerizes either into helices in the presence of lipid templates or into rings in the presence of SH3 domain proteins. Dynasore is a dynamin inhibitor of moderate potency (IC₅₀ ~ 15 μM in vitro). We show that dynasore binds stoichiometrically to detergents used for in vitro drug screening, drastically reducing its potency (IC₅₀ = 479 μM) and research tool utility. We synthesized a focused set of dihydroxyl and trihydroxyl dynasore analogs called the Dyngo™ compounds, five of which had improved potency, reduced detergent binding and reduced cytotoxicity, conferred by changes in the position and/or number of hydroxyl substituents. The Dyngo compound 4a was the most potent compound, exhibiting a 37-fold improvement in potency over dynasore for liposome-stimulated helical dynamin activity. In contrast, while dynasore about equally inhibited dynamin assembled in its helical or ring states, 4a and 6a exhibited >36-fold reduced activity against rings, suggesting that they can discriminate between helical or ring oligomerization states. 4a and 6a inhibited dynamin-dependent endocytosis of transferrin in multiple cell types (IC₅₀ of 5.7 and 5.8 μM, respectively), at least sixfold more potently than dynasore, but had no effect on dynamin-independent endocytosis of cholera toxin. 4a also reduced synaptic vesicle endocytosis and activity-dependent bulk endocytosis in cultured neurons and synaptosomes. Overall, 4a and 6a are improved and versatile helical dynamin and endocytosis inhibitors in terms of potency, non-specific binding and cytotoxicity. The data further suggest that the ring oligomerization state of dynamin is not required for clathrin-mediated endocytosis.

  18. Aurintricarboxylic acid is a potent inhibitor of influenza A and B virus neuraminidases.

    Directory of Open Access Journals (Sweden)

    Anwar M Hashem

    Full Text Available BACKGROUND: Influenza viruses cause serious infections that can be prevented or treated using vaccines or antiviral agents, respectively. While vaccines are effective, they have a number of limitations, and influenza strains resistant to currently available anti-influenza drugs are increasingly isolated. This necessitates the exploration of novel anti-influenza therapies. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the potential of aurintricarboxylic acid (ATA, a potent inhibitor of nucleic acid processing enzymes, to protect Madin-Darby canine kidney cells from influenza infection. We found, by neutral red assay, that ATA was protective, and by RT-PCR and ELISA, respectively, confirmed that ATA reduced viral replication and release. Furthermore, while pre-treating cells with ATA failed to inhibit viral replication, pre-incubation of virus with ATA effectively reduced viral titers, suggesting that ATA may elicit its inhibitory effects by directly interacting with the virus. Electron microscopy revealed that ATA induced viral aggregation at the cell surface, prompting us to determine if ATA could inhibit neuraminidase. ATA was found to compromise the activities of virus-derived and recombinant neuraminidase. Moreover, an oseltamivir-resistant H1N1 strain with H274Y was also found to be sensitive to ATA. Finally, we observed additive protective value when infected cells were simultaneously treated with ATA and amantadine hydrochloride, an anti-influenza drug that inhibits M2-ion channels of influenza A virus. CONCLUSIONS/SIGNIFICANCE: Collectively, these data suggest that ATA is a potent anti-influenza agent by directly inhibiting the neuraminidase and could be a more effective antiviral compound when used in combination with amantadine hydrochloride.

  19. Potent antioxidant and genoprotective effects of boeravinone G, a rotenoid isolated from Boerhaavia diffusa.

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    Gabriella Aviello

    Full Text Available BACKGROUND AND AIMS: Free radicals are implicated in the aetiology of some gastrointestinal disorders such as gastric ulcer, colorectal cancer and inflammatory bowel disease. In the present study we investigated the antioxidant and genoprotective activity of some rotenoids (i.e. boeravinones isolated from the roots of Boerhaavia diffusa, a plant used in the Ayurvedic medicine for the treatment of diseases affecting the gastrointestinal tract. METHODS/PRINCIPAL FINDINGS: Antioxidant activity has been evaluated using both chemical (Electron Spin Resonance spectroscopy, ESR and Caco-2 cells-based (TBARS and ROS assays. DNA damage was evaluated by Comet assay, while pERK(1/2 and phospho-NF-kB p65 levels were estimated by western blot. Boeravinones G, D and H significantly reduced the signal intensity of ESR induced by hydroxyl radicals, suggesting a scavenging activity. Among rotenoids tested, boeravinone G exerted the most potent effect. Boeravinone G inhibited both TBARS and ROS formation induced by Fenton's reagent, increased SOD activity and reduced H(2O(2-induced DNA damage. Finally, boeravinone G reduced the levels of pERK(1 and phospho-NF-kB p65 (but not of pERK(2 increased by Fenton's reagent. CONCLUSIONS: It is concluded that boeravinone G exhibits an extraordinary potent antioxidant activity (significant effect in the nanomolar range. The MAP kinase and NF-kB pathways seem to be involved in the antioxidant effect of boeravinone G. Boeravinone G might be considered as lead compound for the development of drugs potentially useful against those pathologies whose aetiology is related to ROS-mediated injuries.

  20. Database-Guided Discovery of Potent Peptides to Combat HIV-1 or Superbugs

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    Guangshun Wang

    2013-05-01

    Full Text Available Antimicrobial peptides (AMPs, small host defense proteins, are indispensable for the protection of multicellular organisms such as plants and animals from infection. The number of AMPs discovered per year increased steadily since the 1980s. Over 2,000 natural AMPs from bacteria, protozoa, fungi, plants, and animals have been registered into the antimicrobial peptide database (APD. The majority of these AMPs (>86% possess 11–50 amino acids with a net charge from 0 to +7 and hydrophobic percentages between 31–70%. This article summarizes peptide discovery on the basis of the APD. The major methods are the linguistic model, database screening, de novo design, and template-based design. Using these methods, we identified various potent peptides against human immunodeficiency virus type 1 (HIV-1 or methicillin-resistant Staphylococcus aureus (MRSA. While the stepwise designed anti-HIV peptide is disulfide-linked and rich in arginines, the ab initio designed anti-MRSA peptide is linear and rich in leucines. Thus, there are different requirements for antiviral and antibacterial peptides, which could kill pathogens via different molecular targets. The biased amino acid composition in the database-designed peptides, or natural peptides such as θ-defensins, requires the use of the improved two-dimensional NMR method for structural determination to avoid the publication of misleading structure and dynamics. In the case of human cathelicidin LL-37, structural determination requires 3D NMR techniques. The high-quality structure of LL-37 provides a solid basis for understanding its interactions with membranes of bacteria and other pathogens. In conclusion, the APD database is a comprehensive platform for storing, classifying, searching, predicting, and designing potent peptides against pathogenic bacteria, viruses, fungi, parasites, and cancer cells.

  1. The natural product magnolol as a lead structure for the development of potent cannabinoid receptor agonists.

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    Alexander Fuchs

    Full Text Available Magnolol (4-allyl-2-(5-allyl-2-hydroxyphenylphenol, the main bioactive constituent of the medicinal plant Magnolia officinalis, and its main metabolite tetrahydromagnolol were recently found to activate cannabinoid (CB receptors. We now investigated the structure-activity relationships of (tetrahydromagnolol analogs with variations of the alkyl chains and the phenolic groups and could considerably improve potency. Among the most potent compounds were the dual CB1/CB2 full agonist 2-(2-methoxy-5-propyl-phenyl-4-hexylphenol (61a, K(i CB1:0.00957 µM; K(i CB2:0.0238 µM, and the CB2-selective partial agonist 2-(2-hydroxy-5-propylphenyl-4-pentylphenol (60, K(i CB1:0.362 µM; K(i CB2:0.0371 µM, which showed high selectivity versus GPR18 and GPR55. Compound 61b, an isomer of 61a, was the most potent GPR55 antagonist with an IC50 value of 3.25 µM but was non-selective. The relatively simple structures, which possess no stereocenters, are easily accessible in a four- to five-step synthetic procedure from common starting materials. The central reaction step is the well-elaborated Suzuki-Miyaura cross-coupling reaction, which is suitable for a combinatorial chemistry approach. The scaffold is versatile and may be fine-tuned to obtain a broad range of receptor affinities, selectivities and efficacies.

  2. ApoC-III: a potent modulator of hypertriglyceridemia and cardiovascular disease

    Science.gov (United States)

    Kohan, Alison B.

    2015-01-01

    Purpose of review To summarize the recent epidemiological, basic science, and pharmaceutical research linking apoC-III with the development and treatment of cardiovascular disease. Recent findings ApoC-III is an important emerging target linking hypertriglyceridemia with cardiovascular disease (CVD). ApoC-III is a potent modulator of many established CVD risk factors, and is found on chylomicrons, VLDL, LDL, and HDL particles. Recent studies show that in humans, apoC-III levels are an independent risk factor for CVD, and its presence on lipoproteins may promote their atherogenicity. This year, two large-scale epidemiological studies have linked mutations in apoC-III with increased incidence of cardiovascular disease and hypertriglyceridemia. ApoC-III raises plasma triglycerides through inhibition of LPL, stimulation of VLDL secretion, and is a novel factor in modulating intestinal triglyceride trafficking. ApoC-III also stimulates inflammatory processes in the vasculature and in the pancreas. The combination of raising plasma triglycerides and independently stimulating inflammatory processes makes apoC-III a valuable target for reducing the residual CVD risk in patients already on statin therapy, or for whom triglycerides are poorly controlled. Clinical trials on apoC-III antisense oligonucleotides are in progress. Summary ApoC-III is a potent direct modulator of established cardiovascular disease risk factors: plasma triglycerides and inflammation. Recent findings show that changes in apoC-III levels are directly associated with changes in cardiovascular risk, and with the atherogenicity of the lipoproteins on which apoC-III resides. Emerging roles of apoC-III include a role in directing the atherogenicity of HDL, intestinal dietary triglyceride trafficking, and modulating pancreatic β-cell survival. The combination of these roles makes apoC-III an important therapeutic target for the management and prevention of cardiovascular disease. PMID:25692924

  3. Discovery of Potent VEGFR-2 Inhibitors based on Furopyrimidine and Thienopyrimidne Scaffolds as Cancer Targeting Agents

    Science.gov (United States)

    Aziz, Marwa A.; Serya, Rabah A. T.; Lasheen, Deena S.; Abdel-Aziz, Amal Kamal; Esmat, Ahmed; Mansour, Ahmed M.; Singab, Abdel Nasser B.; Abouzid, Khaled A. M.

    2016-04-01

    Vascular endothelial growth factor receptor-2 (VEGFR-2) plays a crucial role in cancer angiogenesis. In this study, a series of novel furo[2,3-d]pyrimidine and thieno[2,3-d]pyrimidine based-derivatives were designed and synthesized as VEGFR-2 inhibitors, in accordance to the structure activity relationship (SAR) studies of known type II VEGFR-2 inhibitors. The synthesized compounds were evaluated for their ability to in vitro inhibit VEGFR-2 kinase enzyme. Seven compounds (15b, 16c, 16e, 21a, 21b, 21c and 21e) demonstrated highly potent dose-related VEGFR-2 inhibition with IC50 values in nanomolar range, of which the thieno[2,3-d]pyrimidine based-derivatives (21b, 21c and 21e) exhibited IC50 values of 33.4, 47.0 and 21 nM respectively. Moreover, furo[2,3-d]pyrimidine-based derivative (15b) showed the strongest inhibition of human umbilical vein endothelial cells (HUVEC) proliferation with 99.5% inhibition at 10 μM concentration. Consistent with our in vitro findings, compounds (21b and 21e) orally administered at 5 and 10 mg/kg/day for 8 consecutive days demonstrated potent anticancer activity in Erhlich ascites carcinoma (EAC) solid tumor murine model. Such compounds blunted angiogenesis in EAC as evidenced by reduced percent microvessel via decreasing VEGFR-2 phosphorylation with subsequent induction of apoptotic machinery. Furthermore, Miles vascular permeability assay confirmed their antiangiogenic effects in vivo. Intriguingly, such compounds showed no obvious toxicity.

  4. Discovery and Characterization of a Potent Interleukin-6 Binding Peptide with Neutralizing Activity In Vivo.

    Directory of Open Access Journals (Sweden)

    Sheila Ranganath

    Full Text Available Interleukin-6 (IL-6 is an important member of the cytokine superfamily, exerting pleiotropic actions on many physiological processes. Over-production of IL-6 is a hallmark of immune-mediated inflammatory diseases such as Castleman's Disease (CD and rheumatoid arthritis (RA. Antagonism of the interleukin IL-6/IL-6 receptor (IL-6R/gp130 signaling complex continues to show promise as a therapeutic target. Monoclonal antibodies (mAbs directed against components of this complex have been approved as therapeutics for both CD and RA. To potentially provide an additional modality to antagonize IL-6 induced pathophysiology, a peptide-based antagonist approach was undertaken. Using a combination of molecular design, phage-display, and medicinal chemistry, disulfide-rich peptides (DRPs directed against IL-6 were developed with low nanomolar potency in inhibiting IL-6-induced pSTAT3 in U937 monocytic cells. Targeted PEGylation of IL-6 binding peptides resulted in molecules that retained their potency against IL-6 and had a prolongation of their pharmacokinetic (PK profiles in rodents and monkeys. One such peptide, PN-2921, contained a 40 kDa polyethylene glycol (PEG moiety and inhibited IL-6-induced pSTAT3 in U937 cells with sub-nM potency and possessed 23, 36, and 59 h PK half-life values in mice, rats, and cynomolgus monkeys, respectively. Parenteral administration of PN-2921 to mice and cynomolgus monkeys potently inhibited IL-6-induced biomarker responses, with significant reductions in the acute inflammatory phase proteins, serum amyloid A (SAA and C-reactive protein (CRP. This potent, PEGylated IL-6 binding peptide offers a new approach to antagonize IL-6-induced signaling and associated pathophysiology.

  5. Novel protein kinase D inhibitors cause potent arrest in prostate cancer cell growth and motility

    Directory of Open Access Journals (Sweden)

    Lazo John S

    2010-05-01

    Full Text Available Abstract Background Protein kinase D (PKD has been implicated in a wide range of cellular processes and pathological conditions including cancer. However, targeting PKD therapeutically and dissecting PKD-mediated cellular responses remains difficult due to lack of a potent and selective inhibitor. Previously, we identified a novel pan-PKD inhibitor, CID755673, with potency in the upper nanomolar range and high selectivity for PKD. In an effort to further enhance its selectivity and potency for potential in vivo application, small molecule analogs of CID755673 were generated by modifying both the core structure and side-chains. Results After initial activity screening, five analogs with equal or greater potencies as CID755673 were chosen for further analysis: kb-NB142-70, kb-NB165-09, kb-NB165-31, kb-NB165-92, and kb-NB184-02. Our data showed that modifications to the aromatic core structure in particular significantly increased potency while retaining high specificity for PKD. When tested in prostate cancer cells, all compounds inhibited PMA-induced autophosphorylation of PKD1, with kb-NB142-70 being most active. Importantly, these analogs caused a dramatic arrest in cell proliferation accompanying elevated cytotoxicity when applied to prostate cancer cells. Cell migration and invasion were also inhibited by these analogs with varying potencies that correlated to their cellular activity. Conclusions Throughout the battery of experiments, the compounds kb-NB142-70 and kb-NB165-09 emerged as the most potent and specific analogs in vitro and in cells. These compounds are undergoing further testing for their effectiveness as pharmacological tools for dissecting PKD function and as potential anti-cancer agents in the treatment of prostate cancer.

  6. Potent innate immune response to pathogenic leptospira in human whole blood.

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    Marga G A Goris

    Full Text Available BACKGROUND: Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. The bacteria enter the human body via abraded skin or mucous membranes and may disseminate throughout. In general the clinical picture is mild but some patients develop rapidly progressive, severe disease with a high case fatality rate. Not much is known about the innate immune response to leptospires during haematogenous dissemination. Previous work showed that a human THP-1 cell line recognized heat-killed leptospires and leptospiral LPS through TLR2 instead of TLR4. The LPS of virulent leptospires displayed a lower potency to trigger TNF production by THP-1 cells compared to LPS of non-virulent leptospires. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the host response and killing of virulent and non-virulent Leptospira of different serovars by human THP-1 cells, human PBMC's and human whole blood. Virulence of each leptospiral strain was tested in a well accepted standard guinea pig model. Virulent leptospires displayed complement resistance in human serum and whole blood while in-vitro attenuated non-virulent leptospires were rapidly killed in a complement dependent manner. In vitro stimulation of THP-1 and PBMC's with heat-killed and living leptospires showed differential serovar and cell type dependence of cytokine induction. However, at low, physiological, leptospiral dose, living virulent complement resistant strains were consistently more potent in whole blood stimulations than the corresponding non-virulent complement sensitive strains. At higher dose living virulent and non-virulent leptospires were equipotent in whole blood. Inhibition of different TLRs indicated that both TLR2 and TLR4 as well as TLR5 play a role in the whole blood cytokine response to living leptospires. CONCLUSIONS/SIGNIFICANCE: Thus, in a minimally altered system as human whole blood, highly virulent Leptospira are potent inducers of the cytokine response.

  7. Synthesis and Bioactivity of Substituted Benzoylguanidine Derivatives as Potent Na+/H+ Exchanger Inhibitors%Synthesis and Bioactivity of Substituted Benzoylguanidine Derivatives as Potent Na+/H+ Exchanger Inhibitors

    Institute of Scientific and Technical Information of China (English)

    Jin, Ning; Yang, Yun; Xu, Wenting; Yang, Xiaozhi; Gong, Guoqing; Xu, Yungen

    2012-01-01

    A novel series of substituted benzoylguanidine derivatives were designed and synthesized in order to evaluate their NHE 1 inhibitory activity. Most of them were found to inhibit NHE 1-mediated platelet swelling in a concentration-dependent manner, and eight compounds showed more potent NHE 1 inhibitory activity than Cariporide. Compound 6f with an IC50 value of 1.08 × 10-10 mol·L-1, was 39 times more potent than lead compound CPU-X-050420 in vitro tests.

  8. Discovery and Optimization of Macrocyclic Quinoxaline-pyrrolo-dihydropiperidinones as Potent Pim-1/2 Kinase Inhibitors.

    Science.gov (United States)

    Cee, Victor J; Chavez, Frank; Herberich, Bradley; Lanman, Brian A; Pettus, Liping H; Reed, Anthony B; Wu, Bin; Wurz, Ryan P; Andrews, Kristin L; Chen, Jie; Hickman, Dean; Laszlo, Jimmy; Lee, Matthew R; Guerrero, Nadia; Mattson, Bethany K; Nguyen, Yen; Mohr, Christopher; Rex, Karen; Sastri, Christine E; Wang, Paul; Wu, Qiong; Wu, Tian; Xu, Yang; Zhou, Yihong; Winston, Jeffrey T; Lipford, J Russell; Tasker, Andrew S; Wang, Hui-Ling

    2016-04-14

    The identification of Pim-1/2 kinase overexpression in B-cell malignancies suggests that Pim kinase inhibitors will have utility in the treatment of lymphoma, leukemia, and multiple myeloma. Starting from a moderately potent quinoxaline-dihydropyrrolopiperidinone lead, we recognized the potential for macrocyclization and developed a series of 13-membered macrocycles. The structure-activity relationships of the macrocyclic linker were systematically explored, leading to the identification of 9c as a potent, subnanomolar inhibitor of Pim-1 and -2. This molecule also potently inhibited Pim kinase activity in KMS-12-BM, a multiple myeloma cell line with relatively high endogenous levels of Pim-1/2, both in vitro (pBAD IC50 = 25 nM) and in vivo (pBAD EC50 = 30 nM, unbound), and a 100 mg/kg daily dose was found to completely arrest the growth of KMS-12-BM xenografts in mice.

  9. The discovery of potent antitumor agent C11-deoxypsymberin/irciniastatin A: total synthesis and biology of advanced psymberin analogs.

    Science.gov (United States)

    Huang, Xianhai; Shao, Ning; Huryk, Robert; Palani, Anandan; Aslanian, Robert; Seidel-Dugan, Cynthia

    2009-02-19

    Structure-activity relationship (SAR) studies by modification of the unsaturated side chain of potent anticancer marine natural product psymberin/irciniastatin A (1) suggest that substitution at C4 and C5 is important for the cytotoxicity of psymberin, but the terminal double bond is not essential for activity. An aryl group is a good replacement for the olefin. The total synthesis of structurally simplified C11-deoxypsymberin (29) was completed, and its activity is consistently more potent than the natural product which provides a unique opportunity for further SAR studies in the psymberin and pederin family. Preliminary mechanism studies suggest the mode of action of psymberin is through cell apoptosis.

  10. Quinoxaline N-oxide containing potent angiotensin II receptor antagonists: synthesis, biological properties, and structure-activity relationships.

    Science.gov (United States)

    Kim, K S; Qian, L; Bird, J E; Dickinson, K E; Moreland, S; Schaeffer, T R; Waldron, T L; Delaney, C L; Weller, H N; Miller, A V

    1993-08-01

    A series of novel quinoxaline heterocycle containing angiotensin II receptor antagonist analogs were prepared. This heterocycle was coupled to the biphenyl moiety via an oxygen atom linker instead of a carbon atom. Many of these analogs exhibit very potent activity and long duration of effect. Interestingly, the N-oxide quinoxaline analog was more potent than the nonoxidized quinoxaline as in the comparison of compounds 5 vs 30. In order to improve oral activity, the carboxylic acid function of these compounds was converted to the double ester. This change did result in an improvement in oral activity as represented by compound 44.

  11. Structure-activity relationships of 1,3-benzoxazole-4-carbonitriles as novel antifungal agents with potent in vivo efficacy.

    Science.gov (United States)

    Kuroyanagi, Jun-ichi; Kanai, Kazuo; Horiuchi, Takao; Takeshita, Hiroshi; Kobayashi, Shozo; Achiwa, Issei; Yoshida, Kumi; Nakamura, Koichi; Kawakami, Katsuhiro

    2011-01-01

    A series of 1,3-benzoxazole-4-carbonitriles was synthesized and evaluated for its antifungal activity, solubility, and metabolic stability. Among those compounds, 4-cyano-N,N,5-trimethyl-7-[(3S)-3-methyl-3-(methylamino)pyrrolidin-1-yl]-6-phenyl-1,3-benzoxazole-2-carboxamide (16b) exhibited potent in vitro activity against Candida species, higher water solubility, and improved metabolic stability compared to lead compound 1. Compound 16b showed potent in vivo efficacy against mice Candida infection models and good bioavailability in rats.

  12. Novel 3-Oxazolidinedione-6-aryl-pyridinones as Potent, Selective, and Orally Active EP3 Receptor Antagonists.

    Science.gov (United States)

    Jin, Jian; Morales-Ramos, Angel; Eidam, Patrick; Mecom, John; Li, Yue; Brooks, Carl; Hilfiker, Mark; Zhang, David; Wang, Ning; Shi, Dongchuan; Tseng, Pei-San; Wheless, Karen; Budzik, Brian; Evans, Karen; Jaworski, Jon-Paul; Jugus, Jack; Leon, Lisa; Wu, Charlene; Pullen, Mark; Karamshi, Bhumika; Rao, Parvathi; Ward, Emma; Laping, Nicholas; Evans, Christopher; Leach, Colin; Holt, Dennis; Su, Xin; Morrow, Dwight; Fries, Harvey; Thorneloe, Kevin; Edwards, Richard

    2010-10-14

    High-throughput screening and subsequent optimization led to the discovery of novel 3-oxazolidinedione-6-aryl-pyridinones exemplified by compound 2 as potent and selective EP3 antagonists with excellent pharmacokinetic properties. Compound 2 was orally active and showed robust in vivo activities in overactive bladder models. To address potential bioactivation liabilities of compound 2, further optimization resulted in compounds 9 and 10, which maintained excellent potency, selectivity, and pharmacokinetic properties and showed no bioactivation liability in glutathione trapping studies. These highly potent, selective, and orally active EP3 antagonists are excellent tool compounds for investigating and validating potential therapeutic benefits from selectively inhibiting the EP3 receptor.

  13. The discovery of novel 3-(pyrazin-2-yl)-1H-indazoles as potent pan-Pim kinase inhibitors.

    Science.gov (United States)

    Wang, Hui-Ling; Cee, Victor J; Chavez, Frank; Lanman, Brian A; Reed, Anthony B; Wu, Bin; Guerrero, Nadia; Lipford, J Russell; Sastri, Christine; Winston, Jeff; Andrews, Kristin L; Huang, Xin; Lee, Matthew R; Mohr, Christopher; Xu, Yang; Zhou, Yihong; Tasker, Andrew S

    2015-02-15

    The three Pim kinases are a small family of serine/threonine kinases regulating several signaling pathways that are fundamental to tumorigenesis. As such, the Pim kinases are a very attractive target for pharmacological inhibition in cancer therapy. Herein, we describe our efforts toward the development of a potent, pan-Pim inhibitor. The synthesis and hit-to-lead SAR development from a 3-(pyrazin-2-yl)-1H-indazole derived hit 2 to the identification of a series of potent, pan-Pim inhibitors such as 13o are described.

  14. Identification of Highly Potent and Selective α-Glucosidase Inhibitors with Antiglycation Potential, Isolated from Rhododendron arboreum

    OpenAIRE

    Rabia Raza; Zaitoon Ilyas; Sajid Ali; Muhammad Nisar; Muhammad Younas Khokhar; Jamshed Iqbal

    2015-01-01

    This study explored antidiabetic potential of eight known pure compounds, isolated from the bark of Rhododendron arboreum. Invitro studies of these compounds against α and β-glucosidases revealed them as very potent and selective inhibitors of α-glucosidase. Compound 7 (3-O-acetylursolic acid) was found to be the most potent inhibitor of α-glucosidase with 3.3±0.1µM IC 50 value which was many folds higher than standard inhibitor acarbose. Antiglycation studies of compounds showed that all com...

  15. Synthesis and Biological Evaluation of Novel Aryl-2H-pyrazole Derivatives as Potent Non-purine Xanthine Oxidase Inhibitors.

    Science.gov (United States)

    Sun, Zhi-Gang; Zhou, Xiao-Jing; Zhu, Ming-Li; Ding, Wen-Ze; Li, Zhen; Zhu, Hai-Liang

    2015-01-01

    A series of aryl-2H-pyrazole derivatives were synthesized and evaluated for inhibitory activity against xanthine oxidase in vitro as potent xanthine oxidase inhibitors. Among them, 2 aryl-2H-pyrazole derivatives showed significant inhibitory activities against xanthine oxidase. Compound 19 emerged as the most potent xanthine oxidase inhibitor (IC50=9.8 µM) in comparison with allopurinol (IC50=9.5 µM). The docking study revealed that compound 19 might have strong interactions with the active site of xanthine oxidase. This compound is thus a new candidate for further development for the treatment of gout.

  16. A New Efficient Synthetic Method for 3-1odothyronamine and Its Potent Hypothermic Efficacy%A New Efficient Synthetic Method for 3-1odothyronamine and Its Potent Hypothermic Efficacy

    Institute of Scientific and Technical Information of China (English)

    Kim, Joong-Gon; Song, Young-Kyu; Jeon, Su-Yeon; Lim, Ye-Ji; Ju, Hyunwo; Choi, Inho; Chung, Chan-Moon

    2011-01-01

    We developed a new efficient synthetic method for a 3-iodothyronamine (TjAM) that has advantages of less synthetic steps and much higher overall yield compared to those in the conventional method. Our animal study showed that TTAM synthesized by the method exerted a potent hypothermic effect in non-hibernator mice.

  17. Cytotoxic and potent CYP1 inhibitors from the marine algae Cymopolia barbata.

    Science.gov (United States)

    Badal, Simone; Gallimore, Winklet; Huang, George; Tzeng, Tzuen-Rong Jeremy; Delgoda, Rupika

    2012-06-11

    Extracts from the marine algae Cymopolia barbata have previously shown promising pharmacological activity including antifungal, antitumor, antimicrobial, and antimutagenic properties. Even though extracts have demonstrated such bioactivity, isolated ingredients responsible for such bioactivity remain unspecified. In this study, we describe chemical characterization and evaluations of biological activity of prenylated bromohydroquinones (PBQ) isolated from the marine algae C. barbata for their cytotoxic and chemopreventive potential. The impact of PBQs on the viability of cell lines (MCF-7, HT29, HepG, and CCD18 Co) was evaluated using the MTS assay. In addition, their inhibitory impact on the activities of heterologously expressed cytochrome P450 (CYP) enzymes (CYP1A1, CYP1A2, CYP1B1, CYP2C19, CYP2D6, and CYP3A4) was evaluated using a fluorescent assay. 7-Hydroxycymopochromanone (PBQ1) and 7-hydroxycymopolone (PBQ2) were isolated using liquid and column chromatography, identified using 1 H and 13 C NMR spectra and compared with the spectra of previously isolated PBQs. PBQ2 selectively impacted the viability of HT29, colon cancer cells with similar potency to the known chemotherapeutic drug, fluorouracil (IC50, 19.82 ± 0.46 μM compared to 23.50 ± 1.12 μM, respectively) with impact toward normal colon cells also being comparable (55.65 ± 3.28 compared to 55.51 ± 3.71 μM, respectively), while PBQ1 had no impact on these cells. Both PBQs had potent inhibition against the activities of CYP1A1 and CYP1B1, the latter which is known to be a universal marker for cancer and a target for drug discovery. Inhibitors of CYP1 enzymes by virtue of the prevention of activation of carcinogens such as benzo-a-pyrene have drawn attention as potential chemopreventors. PBQ2 potently inhibited the activity of CYP1B1 (IC50 0.14 ± 0.04 μM), while both PBQ1 and PBQ2 potently inhibited the activity of CYP1A1 (IC50s of 0.39 ± 0.05 μM and 0.93 ± 0

  18. Curcumin is a potent modulator of microglial gene expression and migration

    Directory of Open Access Journals (Sweden)

    Aslanidis Alexander

    2011-09-01

    Full Text Available Abstract Background Microglial cells are important effectors of the neuronal innate immune system with a major role in chronic neurodegenerative diseases. Curcumin, a major component of tumeric, alleviates pro-inflammatory activities of these cells by inhibiting nuclear factor kappa B (NFkB signaling. To study the immuno-modulatory effects of curcumin on a transcriptomic level, DNA-microarray analyses were performed with resting and LPS-challenged microglial cells after short-term treatment with curcumin. Methods Resting and LPS-activated BV-2 cells were stimulated with curcumin and genome-wide mRNA expression patterns were determined using DNA-microarrays. Selected qRT-PCR analyses were performed to confirm newly identified curcumin-regulated genes. The migration potential of microglial cells was determined with wound healing assays and transwell migration assays. Microglial neurotoxicity was estimated by morphological analyses and quantification of caspase 3/7 levels in 661W photoreceptors cultured in the presence of microglia-conditioned medium. Results Curcumin treatment markedly changed the microglial transcriptome with 49 differentially expressed transcripts in a combined analysis of resting and activated microglial cells. Curcumin effectively triggered anti-inflammatory signals as shown by induced expression of Interleukin 4 and Peroxisome proliferator activated receptor α. Several novel curcumin-induced genes including Netrin G1, Delta-like 1, Platelet endothelial cell adhesion molecule 1, and Plasma cell endoplasmic reticulum protein 1, have been previously associated with adhesion and cell migration. Consequently, curcumin treatment significantly inhibited basal and activation-induced migration of BV-2 microglia. Curcumin also potently blocked gene expression related to pro-inflammatory activation of resting cells including Toll-like receptor 2 and Prostaglandin-endoperoxide synthase 2. Moreover, transcription of NO synthase 2 and

  19. Methylated trivalent arsenicals are potent inhibitors of glucose stimulated insulin secretion by murine pancreatic islets

    Energy Technology Data Exchange (ETDEWEB)

    Douillet, Christelle [Department of Nutrition, Gillings School of Global Public Health, 2302 MHRC, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Currier, Jenna [Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Saunders, Jesse [Department of Nutrition, Gillings School of Global Public Health, 2302 MHRC, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Bodnar, Wanda M. [Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431 (United States); Matoušek, Tomáš [Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 602 00 Brno (Czech Republic); Stýblo, Miroslav, E-mail: styblo@med.unc.edu [Department of Nutrition, Gillings School of Global Public Health, 2302 MHRC, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States)

    2013-02-15

    Epidemiologic evidence has linked chronic exposure to inorganic arsenic (iAs) with an increased prevalence of diabetes mellitus. Laboratory studies have identified several mechanisms by which iAs can impair glucose homeostasis. We have previously shown that micromolar concentrations of arsenite (iAs{sup III}) or its methylated trivalent metabolites, methylarsonite (MAs{sup III}) and dimethylarsinite (DMAs{sup III}), inhibit the insulin-activated signal transduction pathway, resulting in insulin resistance in adipocytes. Our present study examined effects of the trivalent arsenicals on insulin secretion by intact pancreatic islets isolated from C57BL/6 mice. We found that 48-hour exposures to low subtoxic concentrations of iAs{sup III}, MAs{sup III} or DMAs{sup III} inhibited glucose-stimulated insulin secretion (GSIS), but not basal insulin secretion. MAs{sup III} and DMAs{sup III} were more potent than iAs{sup III} as GSIS inhibitors with estimated IC{sub 50} ≤ 0.1 μM. The exposures had little or no effects on insulin content of the islets or on insulin expression, suggesting that trivalent arsenicals interfere with mechanisms regulating packaging of the insulin transport vesicles or with translocation of these vesicles to the plasma membrane. Notably, the inhibition of GSIS by iAs{sup III}, MAs{sup III} or DMAs{sup III} could be reversed by a 24-hour incubation of the islets in arsenic-free medium. These results suggest that the insulin producing pancreatic β-cells are among the targets for iAs exposure and that the inhibition of GSIS by low concentrations of the methylated metabolites of iAs may be the key mechanism of iAs-induced diabetes. - Highlights: ► Trivalent arsenicals inhibit glucose stimulated insulin secretion by pancreatic islets. ► MAs{sup III} and DMAs{sup III} are more potent inhibitors than arsenite with IC{sub 50} ∼ 0.1 μM. ► The arsenicals have little or no effects on insulin expression in pancreatic islets. ► The inhibition of

  20. Adsorption of doxorubicin on citrate-capped gold nanoparticles: insights into engineering potent chemotherapeutic delivery systems

    Science.gov (United States)

    Curry, Dennis; Cameron, Amanda; MacDonald, Bruce; Nganou, Collins; Scheller, Hope; Marsh, James; Beale, Stefanie; Lu, Mingsheng; Shan, Zhi; Kaliaperumal, Rajendran; Xu, Heping; Servos, Mark; Bennett, Craig; Macquarrie, Stephanie; Oakes, Ken D.; Mkandawire, Martin; Zhang, Xu

    2015-11-01

    Gold nanomaterials have received great interest for their use in cancer theranostic applications over the past two decades. Many gold nanoparticle-based drug delivery system designs rely on adsorbed ligands such as DNA or cleavable linkers to load therapeutic cargo. The heightened research interest was recently demonstrated in the simple design of nanoparticle-drug conjugates wherein drug molecules are directly adsorbed onto the as-synthesized nanoparticle surface. The potent chemotherapeutic, doxorubicin often serves as a model drug for gold nanoparticle-based delivery platforms; however, the specific interaction facilitating adsorption in this system remains understudied. Here, for the first time, we propose empirical and theoretical evidence suggestive of the main adsorption process where (1) hydrophobic forces drive doxorubicin towards the gold nanoparticle surface before (2) cation-π interactions and gold-carbonyl coordination between the drug molecule and the cations on AuNP surface facilitate DOX adsorption. In addition, biologically relevant compounds, such as serum albumin and glutathione, were shown to enhance desorption of loaded drug molecules from AuNP at physiologically relevant concentrations, providing insight into the drug release and in vivo stability of such drug conjugates.Gold nanomaterials have received great interest for their use in cancer theranostic applications over the past two decades. Many gold nanoparticle-based drug delivery system designs rely on adsorbed ligands such as DNA or cleavable linkers to load therapeutic cargo. The heightened research interest was recently demonstrated in the simple design of nanoparticle-drug conjugates wherein drug molecules are directly adsorbed onto the as-synthesized nanoparticle surface. The potent chemotherapeutic, doxorubicin often serves as a model drug for gold nanoparticle-based delivery platforms; however, the specific interaction facilitating adsorption in this system remains understudied

  1. Novel phospholipase A2 inhibitors from python serum are potent peptide antibiotics.

    Science.gov (United States)

    Samy, Ramar Perumal; Thwin, Maung Maung; Stiles, Brad G; Satyanarayana-Jois, Seetharama; Chinnathambi, Arunachalam; Zayed, M E; Alharbi, Sulaiman Ali; Siveen, Kodappully Sivaraman; Sikka, Sakshi; Kumar, Alan Prem; Sethi, Gautam; Lim, Lina Hsiu Kim

    2015-04-01

    Antimicrobial peptides (AMPs) play a vital role in defense against resistant bacteria. In this study, eight different AMPs synthesized from Python reticulatus serum protein were tested for bactericidal activity against various Gram-positive and Gram-negative bacteria (Staphylococcus aureus, Burkholderia pseudomallei (KHW and TES strains), and Proteus vulgaris) using a disc-diffusion method (20 μg/disc). Among the tested peptides, phospholipase A2 inhibitory peptide (PIP)-18[59-76], β-Asp65-PIP[59-67], D-Ala66-PNT.II, and D60,65E-PIP[59-67] displayed the most potent bactericidal activity against all tested pathogens in a dose-dependent manner (100-6.8 μg/ml), with a remarkable activity noted against S. aureus at 6.8 μg/ml dose within 6 h of incubation. Determination of minimum inhibitory concentrations (MICs) by a micro-broth dilution method at 100-3.125 μg/ml revealed that PIP-18[59-76], β-Asp65-PIP[59-67] and D-Ala66-PNT.II peptides exerted a potent inhibitory effect against S. aureus and B. pseudomallei (KHW) (MICs 3.125 μg/ml), while a much less inhibitory potency (MICs 12.5 μg/ml) was noted for β-Asp65-PIP[59-67] and D-Ala66-PNT.II peptides against B. pseudomallei (TES). Higher doses of peptides had no effect on the other two strains (i.e., Klebsiella pneumoniae and Streptococcus pneumoniae). Overall, PIP-18[59-76] possessed higher antimicrobial activity than that of chloramphenicol (CHL), ceftazidime (CF) and streptomycin (ST) (30 μg/disc). When the two most active peptides, PIP-18[59-76] and β-Asp65-PIP[59-67], were applied topically at a 150 mg/kg dose for testing wound healing activity in a mouse model of S. aureus infection, the former accelerates faster wound healing than the latter peptide at 14 days post-treatment. The western blot data suggest that the topical application of peptides (PIP-18[59-67] and β-Asp65-PIP[59-67]) modulates NF-kB mediated wound repair in mice with relatively little haemolytic (100-1.56 μg/ml) and cytotoxic (1000

  2. Allorestricted cytotoxic T cells specific for human CD45 show potent antileukemic activity.

    Science.gov (United States)

    Amrolia, Persis J; Reid, Steven D; Gao, Liquan; Schultheis, Beate; Dotti, Gianpietro; Brenner, Malcolm K; Melo, Junia V; Goldman, John M; Stauss, Hans J

    2003-02-01

    Recent advances have made haploidentical transplantation for leukemia feasible, but the rigorous T-cell depletion used contributes to the high relapse rates observed. We have attempted to improve the graft-versus-leukemia (GVL) effect by generating allorestricted cytotoxic T lymphocytes (CTLs) directed against human CD45. Such CTLs should recognize patient hematopoietic cells including leukemia, enhancing donor cell engraftment and improving the GVL effect, but they should not recognize host nonhematopoietic tissues or donor cells from the graft. Using the T2 binding assay, 4 CD45-derived peptides were found to bind HLA-A2 molecules. These peptides were used to generate cytotoxic T-cell lines from HLA-A2(-) donors by sequential stimulation with peptide-pulsed HLA-A2(+) stimulators, and the lines obtained were screened for peptide-specific cytotoxicity. Using one of these peptides (P1218), it was possible to generate peptide-specific, allorestricted CTLs in 3 of 7 responders. P1218-specific CTL lines show potent cytotoxicity against hematopoietic cell lines coexpressing HLA-A2 and CD45 but not CD45 loss variants. Studies with stable transfectants of 293 cells demonstrated recognition by P1218-specific CTLs of endogenously expressed CD45. Likewise P1218-specific CTLs recognized peripheral blood mononuclear cells (PBMCs) from HLA-A2(+) patients with chronic myeloid leukemia (CML) and leukemic blasts in HLA-A2(+) patients with acute myeloid leukemia (AML), but they were unable to lyse HLA-A2(+) fibroblasts or HLA-A2(-) normal PBMCs. Coculture of CD34(+) PBMCs and bone marrow mononuclear cells (BMMCs) with P1218-specific CTL significantly inhibited colony-forming unit-granulocyte macrophage (CFU-GM) formation in HLA-A2(+) healthy controls and CML patients but resulted in no significant inhibition in HLA-A2(-) healthy controls. These studies demonstrate that P1218-specific cytotoxic T lymphocytes (CTLs) have potent activity against leukemic progenitors and suggest that

  3. Development of a potent DOTA-conjugated bombesin antagonist for targeting GRPr-positive tumours

    Energy Technology Data Exchange (ETDEWEB)

    Mansi, Rosalba; Maecke, Helmut R. [University Hospital Basel, Division of Radiological Chemistry, Basel (Switzerland); University of Freiburg, Department of Nuclear Medicine, Freiburg (Germany); Wang, Xuejuan [University Hospital Basel, Division of Radiological Chemistry, Basel (Switzerland); Forrer, Flavio [University Hospital Basel, Institute of Nuclear Medicine, Basel (Switzerland); Erasmus Medical Centre, Nuclear Medicine, Rotterdam (Netherlands); Waser, Beatrice; Cescato, Renzo; Reubi, Jean Claude [University of Berne, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, Berne (Switzerland); Graham, Keith; Borkowski, Sandra [Bayer Schering Pharma AG, Global Drug Discovery, Berlin (Germany)

    2011-01-15

    Radiolabelled somatostatin-based antagonists show a higher uptake in tumour-bearing mouse models than agonists of similar or even distinctly higher receptor affinity. Very similar results were obtained with another family of G protein-coupled receptor ligands, the bombesin family. We describe a new conjugate, RM2, with the chelator DOTA coupled to D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH{sub 2} via the cationic spacer 4-amino-1-carboxymethyl-piperidine for labelling with radiometals such as {sup 111}In and {sup 68}Ga. RM2 was synthesized on a solid support and evaluated in vitro in PC-3 cells. IC{sub 50} and K{sub d} values were determined. The antagonist potency was evaluated by immunofluorescence-based internalization and Ca{sup 2+} mobilization assays. Biodistribution studies were performed in PC-3 and LNCaP tumour-bearing mice with {sup 111}In-RM2 and {sup 68}Ga-RM2, respectively. PET/CT studies were performed on PC-3 and LNCaP tumour-bearing nude mice with {sup 68}Ga-RM2. RM2 and {sup 111}In-RM2 are high-affinity and selective ligands for the GRP receptor (7.7{+-}3.3 nmol/l for RM2; 9.3{+-}3.3 nmol/l for {sup nat}In-RM2). The potent antagonistic properties were confirmed by an immunofluorescence-based internalization and Ca{sup 2+} mobilization assays. {sup 68}Ga- and {sup 111}In-RM2 showed high and specific uptake in both the tumour and the pancreas. Uptake in the tumour remained high (15.2{+-}4.8%IA/g at 1 h; 11.7{+-}2.4%IA/g at 4 h), whereas a relatively fast washout from the pancreas and the other abdominal organs was observed. Uptake in the pancreas decreased rapidly from 22.6{+-}4.7%IA/g at 1 h to 1.5{+-}0.5%IA/g at 4 h. RM2 was shown to be a potent GRPr antagonist. Pharmacokinetics and imaging studies indicate that {sup 111}In-RM2 and {sup 68}Ga-RM2 are ideal candidates for clinical SPECT and PET studies. (orig.)

  4. HDL cholesterol, size, particle number, and residual vascular risk after potent statin therapy

    Science.gov (United States)

    Mora, Samia; Glynn, Robert J.; Ridker, Paul M

    2013-01-01

    Background Chemically-measured high-density lipoprotein cholesterol (HDL-C) may not be the best clinical measure of HDL. Little is known about alternative HDL meassures such as HDL size or particle number (HDL-P) as determinants of residual risk after potent statin therapy. Methods and Results In JUPITER, HDL size and HDL-P were measured by nuclear magnetic resonance spectroscopy, and HDL-C and apolipoprotein A-I (apoA-I) were chemically assayed in 10,886 participants without cardiovascular disease (CVD) before and after random allocation to rosuvastatin 20 mg/day or placebo. Levels were examined with first CVD (N=234). HDL-P correlated better with apoA-I (Spearman r=0.69, pHDL-C (r=0.55, pHDL-C (6.1%), apoA-I (2.1%), HDL-P (3.8%) and HDL size (1.2%); all pHDL-C, apoA-I, and HDL-P had similar inverse associations with CVD (risk factor-adjusted hazard ratio and 95% CI per 1-SD: 0.79 [0.63–0.98], 0.75 [0.62–0.92], and 0.81 [0.67–0.97], respectively). Among rosuvastatin-allocated individuals, on-treatment HDL-P had a statistically significant and somewhat stronger association with CVD (0.73, 0.57–0.93, p=0.01) than HDL-C (0.82, 0.63–1.08, p=0.16) or apoA-I (0.86, 0.67–1.10, p=0.22). Among rosuvastatin-allocated individuals, on-treatment HDL-P remained significant (0.72, 0.53–0.97, p=0.03) after additionally adjusting for HDL-C. In risk factor-adjusted models, HDL size showed no significant association with CVD. Conclusions In the setting of potent statin therapy, HDL particle number may be a better marker of residual risk than chemically-measured HDL-C or apoA-I. This has potential implications for evaluating novel therapies targeting HDL. Clinical Trial Registration ClinicalTrials.gov; NCT00239681 PMID:24002795

  5. Stereochemistry and molecular pharmacology of (S)-thio-ATPA, a new potent and selective GluR5 agonist

    DEFF Research Database (Denmark)

    Stensbøl, T B; Jensen, H S; Nielsen, B

    2001-01-01

    )-Glu) receptors (EC(50)=14 microM), comparable in potency with ATPA (EC(50)=34 microM). Recent findings, that (S)-ATPA is a potent (EC(50)=0.48 microM) and selective agonist at homomerically expressed ionotropic GluR5, prompted us to resolve thio-ATPA using chiral chromatography and pharmacologically characterize...

  6. Synthesis and evaluation of novel azetidine analogs as potent inhibitors of vesicular [3H]dopamine uptake.

    Science.gov (United States)

    Ding, Derong; Nickell, Justin R; Deaciuc, Agripina G; Penthala, Narsimha Reddy; Dwoskin, Linda P; Crooks, Peter A

    2013-11-01

    Lobelane analogs that incorporate a central piperidine or pyrrolidine moiety have previously been reported by our group as potent inhibitors of VMAT2 function. Further central ring size reduction of the piperidine moiety in lobelane to a four-membered heterocyclic ring has been carried out in the current study to afford novel cis-and trans-azetidine analogs. These azetidine analogs (15a-15c and 22a-22c) potently inhibited [(3)H]dopamine (DA) uptake into isolated synaptic vesicles (Ki⩽66nM). The cis-4-methoxy analog 22b was the most potent inhibitor (Ki=24nM), and was twofold more potent that either lobelane (2a, Ki=45nM) or norlobelane (2b, Ki=43nM). The trans-methylenedioxy analog, 15c (Ki=31nM), was equipotent with the cis-analog, 22b, in this assay. Thus, cis- and trans-azetidine analogs 22b and 15c represent potential leads in the discovery of new clinical candidates for the treatment of methamphetamine abuse.

  7. Abietane-Type Diterpenoid Amides with Highly Potent and Selective Activity against Leishmania donovani and Trypanosoma cruzi.

    Science.gov (United States)

    Pirttimaa, Minni; Nasereddin, Abedelmajeed; Kopelyanskiy, Dmitry; Kaiser, Marcel; Yli-Kauhaluoma, Jari; Oksman-Caldentey, Kirsi-Marja; Brun, Reto; Jaffe, Charles L; Moreira, Vânia M; Alakurtti, Sami

    2016-02-26

    Dehydroabietylamine (1) was used as a starting material to synthesize a small library of dehydroabietyl amides by simple and facile methods, and their activities against two disease-causing trypanosomatids, namely, Leishmania donovani and Trypanosoma cruzi, were assayed. The most potent compound, 10, an amide of dehydroabietylamine and acrylic acid, was found to be highly potent against these parasites, displaying an IC50 value of 0.37 μM against L. donovani axenic amastigotes and an outstanding selectivity index of 63. Moreover, compound 10 fully inhibited the growth of intracellular amastigotes in Leishmania donovani-infected human macrophages with a low IC50 value of 0.06 μM. This compound was also highly effective against T. cruzi amastigotes residing in L6 cells with an IC50 value of 0.6 μM and high selectivity index of 58, being 3.5 times more potent than the reference compound benznidazole. The potent activity of this compound and its relatively low cytotoxicity make it attractive for further development in pursuit of better drugs for patients suffering from leishmaniasis and Chagas disease.

  8. The TLR9 agonist MGN1703 triggers a potent type I interferon response in the sigmoid colon

    DEFF Research Database (Denmark)

    Krarup, A R; Abdel-Mohsen, M; Schleimann, M H

    2017-01-01

    to the change in integrated HIV DNA during MGN1703 treatment (P=0.020). In conclusion, MGN1703 induced a potent type I IFN response, without a concomitant general inflammatory response, in the intestines.Mucosal Immunology advance online publication, 02 August 2017; doi:10.1038/mi.2017.59....

  9. The bispyridinium-dioxime HLö-7. A potent reactivator for acetylcholinesterase inhibited by the stereoisomers of tabun and soman

    NARCIS (Netherlands)

    Jong, L.P.A.de; Verhagen, M.A.A.; Langenberg, J.P.; Hagedorn, I.; Löffler, M.

    1989-01-01

    Purification of (+)-tabun was accomplished by treatment with electric eel acetylcholinesterase (AChE) in order to bind contaminating (-)-tabun, the more potent enantiomer with respect of AChE inhibition. Electric eel AChE inhibited with (-)-tabun and with purified (+)-tabun show similar properties i

  10. Preclinical Metabolism and Pharmacokinetics of SB1317 (TG02), a Potent CDK/JAK2/FLT3 Inhibitor

    NARCIS (Netherlands)

    Pasha, Mohammed Khalid; Jayaraman, Ramesh; Reddy, Venkatesh Pilla; Yeo, Pauline; Goh, Evelyn; Williams, Anthony; Goh, Kee Chuan; Kantharaj, Ethirajulu

    2012-01-01

    SB1317 (TG02) is a novel small molecule potent CDK/JAK2/FLT3 inhibitor. To evaluate full potential of this development candidate, we conducted drug metabolism and pharmacokinetic studies of this novel anti-cancer agent. SB1317 was soluble, highly permeable in Caco-2 cells, and showed >99% binding to

  11. Rational design and synthesis of 1,5-disubstituted tetrazoles as potent inhibitors of the MDM2-p53 interaction

    NARCIS (Netherlands)

    Surmiak, Ewa; Neochoritis, Constantinos G; Musielak, Bogdan; Twarda-Clapa, Aleksandra; Kurpiewska, Katarzyna; Dubin, Grzegorz; Camacho, Carlos; Holak, Tad A; Dömling, Alexander

    2016-01-01

    Using the computational pharmacophore-based ANCHOR.QUERY platform a new scaffold was discovered. Potent compounds evolved inhibiting the protein-protein interaction p53-MDM2. An extensive SAR study was performed based on our four-point pharmacophore model, yielding derivatives with affinity to MDM2

  12. Rational design and synthesis of 1,5-disubstituted tetrazoles as potent inhibitors of the MDM2-p53 interaction

    NARCIS (Netherlands)

    Surmiak, Ewa; Neochoritis, Constantinos G; Musielak, Bogdan; Twarda-Clapa, Aleksandra; Kurpiewska, Katarzyna; Dubin, Grzegorz; Camacho, Carlos; Holak, Tad A; Dömling, Alexander

    2016-01-01

    Using the computational pharmacophore-based ANCHOR.QUERY platform a new scaffold was discovered. Potent compounds evolved inhibiting the protein-protein interaction p53-MDM2. An extensive SAR study was performed based on our four-point pharmacophore model, yielding derivatives with affinity to MDM2

  13. Production and dosimetric aspects of the potent Auger emitter Co-58m for targeted radionuclide therapy of small tumours

    DEFF Research Database (Denmark)

    Thisgaard, Helge; Elema, Dennis Ringkjøbing; Jensen, Mikael

    2011-01-01

    Based on theoretical calculations, the Auger emitter 58mCo has been identified as a potent nuclide for targeted radionuclide therapy of small tumors. During the production of this isotope, the coproduction of the long-lived ground state 58gCo is unfortunately unavoidable, as is ingrowth...

  14. Draft Genome Sequence of Pseudomonas sp. Strain In5 Isolated from a Greenlandic Disease Suppressive Soil with Potent Antimicrobial Activity

    DEFF Research Database (Denmark)

    Hennessy, Rosanna C.; Glaring, Mikkel Andreas; Frydenlund Michelsen, Charlotte;

    2015-01-01

    Pseudomonas sp. In5 is an isolate of disease suppressive soil with potent activity against pathogens. Its antifungal activity has been linked to a gene cluster encoding nonribosomal peptide synthetases producing the peptides nunamycin and nunapeptin. The genome sequence will provide insight...... into the genetics behind the antimicrobial activity of this strain....

  15. 3-Amido-3-aryl-piperidines: A Novel Class of Potent, Selective, and Orally Active GlyT1 Inhibitors.

    Science.gov (United States)

    Pinard, Emmanuel; Alberati, Daniela; Alvarez-Sanchez, Ruben; Brom, Virginie; Burner, Serge; Fischer, Holger; Hauser, Nicole; Kolczewski, Sabine; Lengyel, Judith; Mory, Roland; Saladin, Christian; Schulz-Gasch, Tanja; Stalder, Henri

    2014-04-10

    3-Amido-3-aryl-piperidines were discovered as a novel structural class of GlyT1 inhibitors. The structure-activity relationship, which was developed, led to the identification of highly potent compounds exhibiting excellent selectivity against the GlyT2 isoform, drug-like properties, and in vivo activity after oral administration.

  16. In vitro and mouse in vivo characterization of the potent free fatty acid 1 receptor agonist TUG-469

    DEFF Research Database (Denmark)

    Urban, C; Hamacher, A; Partke, H J;

    2013-01-01

    Activation of the G protein-coupled free fatty acid receptor 1 (FFA1; formerly known as GPR40) leads to an enhancement of glucose-stimulated insulin secretion from pancreatic β-cells. TUG-469 has previously been reported as a potent FFA1 agonist. This study was performed to confirm the higher in ...

  17. Development of potent fluorescent polyamine toxins and application in labeling of ionotropic glutamate receptors in hippocampal neurons

    DEFF Research Database (Denmark)

    Nørager, Niels Grøn; Jensen, Christel Barker; Rathje, Mette;

    2013-01-01

    The natural product argiotoxin-636 (ArgTX-636) found in the venom of the Argiope lobata spider is a potent open-channel blocker of ionotropic glutamate (iGlu) receptors, and recently, two analogues, ArgTX-75 and ArgTX-48, were identified with increased potency and selectivity for iGlu receptor...

  18. Absorption, distribution, and biliary excretion of cafestol, a potent cholesterol-elevating compound in unfiltered coffees, in mice

    NARCIS (Netherlands)

    Cruchten, S.T.J. van; Waart, D.R. de; Kunne, C.; Hooiveld, G.J.E.J.; Boekschoten, M.V.; Katan, M.B.; Oude Elferink, R.P.J.; Witkamp, R.F.

    2010-01-01

    Cafestol is a diterpene present in unfiltered coffees. It is the most potent cholesterol-elevating compound present in the human diet. However, the precise mechanisms underlying this effect are still unclear. In contrast, cafestol is also known as a hepatoprotective compound, which is likely to be r

  19. Design and synthesis of 4-substituted quinazolines as potent EGFR inhibitors with anti-breast cancer activity.

    Science.gov (United States)

    Ahmed, Marwa; Magdy, Naja

    2016-09-23

    Cancer is a major health problem to human beings around the world. Many quinazoline derivatives were reported to have potent cytotoxic activity. Our aim in this work is the discovery of potent epidermal growth factor receptor (EGFR) inhibitors with anti-breast cancer activity containing 4-substituted quinazoline pharmacophore. Novel series of 4-substituted 6,8-dibromo-2-(4-chlorophenyl)-quinazoline derivatives have been designed and synthesized. New derivatives were tested against MCF-7 (human breast carcinoma cell line) and screened for their inhibition activity against epidermal growth factor receptor tyrosine kinase (EGFR-TK). Most of the tested compounds show potent antiproliferative activity and EGFR-TK inhibitory activity. Compounds VIIIc and VIIIb exerted powerful cytotoxic activity (IC50 3.1 and 6.3 µM) with potent inhibitory percent (91.1 and 88.4%) against EGFR-TK. Compounds IX, VIIa, X, VIIb, VIc, V, IV, VIa and VIb showed promising cytotoxic effects with IC50 range (12-79 µM) with good activity against EGFR-TK with the inhibitory percent (85.4-60.8%). On the other hand, compounds VIIc, VIIIa exerted low cytotoxic effects as revealed from their IC50 value (124 and 144 µM) with low activity against EGFR-TK with inhibitory percent 30.6 and 29.1% respectively.

  20. Dynamic Function of the Alkyl Spacer of Acetogenins as Potent Inhibitors of Mitochondrial Complex I. A Molecular Dynamics Simulation Approach

    NARCIS (Netherlands)

    Abel Bombasaro, Jose; Barrera Guisasola, Exequiel Ernesto; Masman, Marcelo Fabricio; Angel Zamora, Miguel; Maria Rodriguez, Ana

    2013-01-01

    Acetogenins are among the most potent of the known inhibitors of complex I (NADH-ubiquinone oxidoreductase) in mitochondrial electron transfer system. Elucidation of the dynamic function of the alkyl spacer linking the two toxophores (i.e., the hydroxylated tetrahydrofuran and the gamma-lactone

  1. [Experience of the development special medical technical laboratory for studies of effects caused by potent electromagnetic radiation in biologic objects].

    Science.gov (United States)

    Gorodetsky, B N; Kalyada, T V; Petrov, S V

    2015-01-01

    This article covers topics of creating special medical technical laboratory for medial and biologic studies concerning influence of potent high-frequency elecromagnetic radiation on various biologic objects. The authors gave example of such laboratory, described its construction features, purpose and main characteristics of the included devices.

  2. Agonistic CD200R1 DNA Aptamers Are Potent Immunosuppressants That Prolong Allogeneic Skin Graft Survival

    Directory of Open Access Journals (Sweden)

    Aaron Prodeus

    2014-01-01

    Full Text Available CD200R1 expressed on the surface of myeloid and lymphoid cells delivers immune inhibitory signals to modulate inflammation when engaged with its ligand CD200. Signalling through CD200/CD200R1 has been implicated in a number of immune-related diseases including allergy, infection, cancer and transplantation, as well as several autoimmune disorders including arthritis, systemic lupus erythematosus, and multiple sclerosis. We report the development and characterization of DNA aptamers, which bind to murine CD200R1 and act as potent signalling molecules in the absence of exogenous CD200. These agonistic aptamers suppress cytotoxic T-lymphocyte induction in 5-day allogeneic mixed leukocyte culture and induce rapid phosphorylation of the CD200R1 cytoplasmic tail thereby initiating immune inhibitory signalling. PEGylated conjugates of these aptamers show significant in vivo immunosuppression and enhance survival of allogeneic skin grafts as effectively as soluble CD200Fc. As DNA aptamers exhibit inherent advantages over conventional protein-based therapeutics including low immunogenicity, ease of synthesis, low cost, and long shelf life, such CD200R1 agonistic aptamers may emerge as useful and safe nonsteroidal anti-inflammatory therapeutic agents.

  3. TRAF4 is potently induced by TAp63 isoforms and localised according to differentiation in SCCHN.

    Science.gov (United States)

    Gu, Xiaolian; Coates, Philip J; MacCallum, Stephanie F; Boldrup, Linda; Sjöström, Björn; Nylander, Karin

    2007-12-01

    p63, a member of the p53 family, is overexpressed in squamous cell carcinoma of the head and neck (SCCHN) and some other tumors of epithelial origin. As a transcription factor, p63 can bind to p53-type response elements and there is some overlap between p53 family transcriptional targets. Tumor necrosis factor receptor associated factor 4 (TRAF4) is a p53 regulated gene which is overexpressed in many human carcinomas. We investigated the involvement of p63 in regulation of TRAF4 and the expression of the TRAF4 protein in SCCHN. Disrupting endogenous p63 expression resulted in downregulation of TRAF4 mRNA and protein in an SCCHN cell line. Endogenous p63 bound to the TRAF4 promoter in vivo and reporter assays showed that p63, p73 and p53 can all transactivate TRAF4, with TAp63 isoforms being the most potent activators. The level of TRAF4 activation by TAp63 was two-fold higher than by p53, and TRAF4 was ten-fold more responsive to TAp63 than another p63-target, IGFBP3. Nuclear expression of TRAF4 was seen in normal oral epithelium and highly/moderately differentiated SCCHN, whereas cytoplasmic expression of TRAF4 was seen in poorly differentiated SCCHN. These results indicate that TRAF4 is a common target of p53 family members and that localization of TRAF4 is associated with differentiation of SCCHN cells.

  4. Berberine potentizes apoptosis induced by X-rays irradiation probably through modulation of gap junctions

    Institute of Scientific and Technical Information of China (English)

    LIU Bing; WANG Qin; YUAN Dong-dong; HONG Xiao-ting; TAO Liang

    2011-01-01

    Background Clinical combination of some traditional Chinese medical herbs, including berberine, with irradiation is demonstrated to improve efficacy of tumor radiotherapy, yet the mechanisms for such effect remain largely unknown. The present study investigated the effect of berberine on apoptosis induced by X-rays irradiation and the relation between this effect and gap junction intercellular communication (GJIC).Methods The role of gap junctions in the modulation of X-rays irradiation-induced apoptosis was explored by manipulation of connexin (Cx) expression, and gap junction function, using oleamide, a GJIC inhibitor, and berberine.Results In transfected HeLa cells, Cx32 expression increased apoptosis induced by X-rays irradiation, while inhibition of gap junction by oleamide reduced the irradiation responses, indicating the dependence of X-rays irradiation-induced apoptosis on GJIC. Berberine, at the concentrations without cytotoxicity, enhanced apoptosis induced by irradiation only in the presence of functional gap junctions.Conclusions These results suggest that berberine potentizes cell apoptosis induced by X-rays irradiation, probably through enhancement of gap junction activity.

  5. Sulfonylureas have antifungal activity and are potent inhibitors of Candida albicans acetohydroxyacid synthase.

    Science.gov (United States)

    Lee, Yu-Ting; Cui, Chang-Jun; Chow, Eve W L; Pue, Nason; Lonhienne, Thierry; Wang, Jian-Guo; Fraser, James A; Guddat, Luke W

    2013-01-10

    The sulfonylurea herbicides exert their activity by inhibiting plant acetohydroxyacid synthase (AHAS), the first enzyme in the branched-chain amino acid biosynthesis pathway. It has previously been shown that if the gene for AHAS is deleted in Candida albicans , attenuation of virulence is achieved, suggesting AHAS as an antifungal drug target. Herein, we have cloned, expressed, and purified C. albicans AHAS and shown that several sulfonylureas are inhibitors of this enzyme and possess antifungal activity. The most potent of these compounds is ethyl 2-(N-((4-iodo-6-methoxypyrimidin-2-yl)carbamoyl)sulfamoyl)benzoate (10c), which has a K(i) value of 3.8 nM for C. albicans AHAS and an MIC₉₀ of 0.7 μg/mL for this fungus in cell-based assays. For the sulfonylureas tested there was a strong correlation between inhibitory activity toward C. albicans AHAS and fungicidal activity, supporting the hypothesis that AHAS is the target for their inhibitory activity within the cell.

  6. Low Molecular Weight Amidoximes that Act as Potent Inhibitors of Lysine-Specific Demethylase 1

    Science.gov (United States)

    Hazeldine, Stuart; Pachaiyappan, Boobalan; Steinbergs, Nora; Nowotarski, Shannon; Hanson, Allison S.; Casero, Robert A.; Woster, Patrick M.

    2012-01-01

    The recently discovered enzyme lysine-specific demethylase 1 (LSD1) plays an important role in the epigenetic control of gene expression, and aberrant gene silencing secondary to LSD1 dysregulation is thought to contribute to the development of cancer. We reported that (bis)guanidines, (bis)biguanides and their urea- and thiourea isosteres are potent inhibitors of LSD1, and induce the re-expression of aberrantly silenced tumor suppressor genes in tumor cells in vitro. We now report a series of small molecule amidoximes that are moderate inhibitors of recombinant LSD1, but that produce dramatic changes in methylation at the histone 3 lysine 4 (H3K4) chromatin mark, a specific target of LSD1, in Calu-6 lung carcinoma cells. In addition, these analogues increase cellular levels of secreted frizzle-related protein (SFRP) 2, H-cadherin (HCAD) and transcription factor GATA4. These compounds represent leads for an important new series of drug-like epigenetic modulators with the potential for use as antitumor agents. PMID:22876979

  7. Potent, selective, and orally efficacious antagonists of melanin-concentrating hormone receptor 1.

    Science.gov (United States)

    Tavares, Francis X; Al-Barazanji, Kamal A; Bigham, Eric C; Bishop, Michael J; Britt, Christy S; Carlton, David L; Feldman, Paul L; Goetz, Aaron S; Grizzle, Mary K; Guo, Yu C; Handlon, Anthony L; Hertzog, Donald L; Ignar, Diane M; Lang, Daniel G; Ott, Ronda J; Peat, Andrew J; Zhou, Hui-Qiang

    2006-11-30

    The high expression of MCH in the hypothalamus with the lean hypophagic phenotype coupled with increased resting metabolic rate and resistance to high fat diet-induced obesity of MCH KO mice has spurred considerable efforts to develop small molecule MCHR1 antagonists. Starting from a lead thienopyrimidinone series, structure-activity studies at the 3- and 6-positions of the thienopyrimidinone core afforded potent and selective MCHR1 antagonists with representative examples having suitable pharmacokinetic properties. Based on structure-activity relationships, a structural model for MCHR1 was constructed to explain the binding mode of these antagonists. In general, a good correlation was observed between pKas and activity in the right-hand side of the template, with Asp123 playing an important role in the enhancement of binding affinity. A representative example when evaluated chronically in diet-induced obese mice resulted in good weight loss effects. These antagonists provide a viable lead series in the discovery of new therapies for the treatment of obesity.

  8. An active film-coating approach to enhance chemical stability of a potent drug molecule.

    Science.gov (United States)

    Desai, Divyakant; Rao, Venkatramana; Guo, Hang; Li, Danping; Stein, Daniel; Hu, Frank Y; Kiesnowski, Chris

    2012-01-01

    Peliglitazar, a PPAR α/γ agonist, was found to undergo acid as well as base catalyzed degradation. The acid catalyzed degradation led to the formation of benzylic alcohol and glycine carbamate and the base catalyzed degradation led to formation of p-hydroxyanisole and an amine degradant. In capsule formulations, the capsules with the lowest drug-loading exhibited maximum instability even at 25 °C/60% RH storage condition. Incorporation of pH-modifiers to maintain 'micro-environmental pH' acidic did not prevent the formation of the base-catalyzed degradants. Traditional dry granulated tablet formulation which is qualitatively similar to the capsule formulations showed the presence of acid-catalyzed degradants even without the presence of an acidifying agent. On the other hand, traditional wet granulated tablet formulation showed mainly base-catalyzed degradants. Stability problems of the tablet formulation were aggravated because the potent molecule required low tablet strengths which resulted in low drug to excipient ratio. To stabilize the molecule, an active film-coating approach was explored. In this approach, the drug was sprayed with the coating material onto non-active containing tablet cores. This approach of trapping the drug particles into the coating material provided tablets with satisfactory chemical stability. The stability enhancement observed in the active coating approach is attributed to the higher drug to excipient ratio in the film coat of non-reactive coating material compared to that in the traditional dry or wet granulated formulations.

  9. Synthetic Pre-miRNA-Based shRNA as Potent RNAi Triggers

    Directory of Open Access Journals (Sweden)

    Kazuya Terasawa

    2011-01-01

    Full Text Available RNA interference (RNAi is a powerful tool for studying gene function owing to the ease with which it can selectively silence genes of interest, and it has also attracted attention because of its potential for therapeutic applications. Chemically synthesized small interfering RNAs (siRNAs and DNA vector-based short hairpin RNAs (shRNAs are now widely used as RNAi triggers. In contrast to expressed shRNAs, the use of synthetic shRNAs is limited. Here we designed shRNAs modeled on a precursor microRNA (pre-miRNA and evaluated their biological activity. We demonstrated that chemically synthetic pre-miRNA-based shRNAs have more potent RNAi activity than their corresponding siRNAs and found that their antisense strands are more efficiently incorporated into the RNA-induced silencing complex. Although greater off-target effects and interferon responses were induced by shRNAs than by their corresponding siRNAs, these effects could be overcome by simply using a lower concentration or by optimizing and chemically modifying shRNAs similar to synthetic siRNAs. These are challenges for the future.

  10. Effect of cysteine and cystine addition on sensory profile and potent odorants of extruded potato snacks.

    Science.gov (United States)

    Majcher, Małgorzata A; Jeleń, Henryk H

    2007-07-11

    Aromas generated in extruded potato snacks without and with addition of 0.25, 0.5, and 1% (w/w) of flavor precursors, cysteine and cystine, were compared and evaluated by descriptive sensory profiling. The results showed that high addition of cysteine (0.5 and 1%) resulted in the formation of undesirable odor and taste described as mercaptanic/sulfur, onion-like, and bitter; on the contrary, addition of cystine even at high concentration gave product with pleasant odor and taste, slightly changed into breadlike notes. GC/O analysis showed cysteine to be a much more reactive flavor precursor than cystine, stimulating formation of 12 compounds with garlic, sulfury, burnt, pungent/beer, cabbage/mold, meatlike, roasted, and popcorn odor notes. Further analysis performed by the AEDA technique identified 2-methyl-3-furanthiol (FD 2048) as a most potent odorant of extruded potato snacks with 1% addition of cysteine. Other identified compounds with high FD were butanal, 3-methyl-2-butenethiol, 2-methylthiazole, methional, 2-acetyl-1-pyrroline, and 3-hydroxy-4,5-dimethyl-2(5H)-furanone. In the case of cystine addition (1%) the highest FD factors were calculated for butanal, 2-acetyl-1-pyrroline, benzenemethanethiol, methional, phenylacetaldehyde, dimethyltrisulfide, 1-octen-3-ol, 1,5-octadien-3-one, and 2-acetylpyrazine.

  11. Toward potent antibiofilm degradable medical devices: a generic method for the antibacterial surface modification of polylactide.

    Science.gov (United States)

    El Habnouni, Sarah; Lavigne, Jean-Philippe; Darcos, Vincent; Porsio, Barbara; Garric, Xavier; Coudane, Jean; Nottelet, Benjamin

    2013-08-01

    The effects of biomaterials on their environment must be carefully modulated in most biomedical applications. Among other approaches, this modulation can be obtained through the modification of the biomaterial surface. This paper proposes a simple and versatile strategy to produce non-leaching antibacterial polylactide (PLA) surfaces without any degradation of the polyester chains. The method is based on a one-pot procedure that provides a "clickable" PLA surface via anionic activation which is then functionalized with an antibacterial quaternized poly(2-(dimethylamino)ethyl methacrylate) (QPDMAEMA) by covalent immobilization on the surface. The anti-adherence and antibiofilm activities of modified PLA surfaces are assessed for different QPDMAEMA molecular weights and different quaternization agents. Antibacterial PLA surfaces are shown to be very active against Gram-negative and Gram-positive strains, with adherence reduction factors superior to 99.999% and a marked reduction in biofilm on the most potent surfaces. In addition to this substantial antibacterial activity, the proposed PLA surfaces are also cytocompatible, as demonstrated through the proliferation of L929 fibroblasts. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Discovery of Metal Ions Chelator Quercetin Derivatives with Potent Anti-HCV Activities

    Directory of Open Access Journals (Sweden)

    Dongwei Zhong

    2015-04-01

    Full Text Available Analogues or isosteres of α,γ-diketoacid (DKA 1a show potent inhibition of hepatitis C virus (HCV NS5B polymerase through chelation of the two magnesium ions at the active site. The anti-HCV activity of the flavonoid quercetin (2 could partly be attributed to it being a structural mimic of DKAs. In order to delineate the structural features required for the inhibitory effect and improve the anti-HCV potency, two novel types of quercetin analogues, 7-O-arylmethylquercetins and quercetin-3-O-benzoic acid esters, were designed, synthesized and evaluated for their anti-HCV properties in cell-based assays. Among the 38 newly synthesized compounds, 7-O-substituted derivative 3i and 3-O-substituted derivative 4f were found to be the most active in the corresponding series (EC50 = 3.8 μM and 9.0 μΜ, respectively. Docking studies suggested that the quercetin analogues are capable of establishing key coordination with the two magnesium ions as well as interactions with residues at the active site of HCV NS5B.

  13. Tetrahydroamentoflavone (THA) from Semecarpus anacardium as a potent inhibitor of xanthine oxidase.

    Science.gov (United States)

    Arimboor, Ranjith; Rangan, Meena; Aravind, S G; Arumughan, C

    2011-02-16

    Seed of Semecarpus anacardium L. is widely used in Indian traditional medicine; Ayurveda and Sidha, for treatment of inflammatory disorders and gout. The present study was aimed at isolation of a compound for its potential to inhibit xanthine oxidase (XO), over expression of which lead to inflammation and gout. Activity guided fractionation of S. anacardium seed was conducted using liquid-liquid partition and preparative HPLC. The fractions were evaluated for their XO inhibition and antioxidant activity. The ethyl acetate fraction with the highest XO activity yielded a biflavonoid compound tetrahydroamentoflavone (THA). Lineweaver-Burk (LB) plot for the XO inhibition of THA and allopurinol was constructed from the kinetic data. IC₅₀ values of THA and allopurinol for XO inhibition were 92 and 100 nM respectively and their corresponding values for K(i) were 0.982 and 0.612 μM respectively. THA was a potent XO inhibitor which could be considered as a drug candidate or chemopreventive agent, after establishing its pharmacological and clinical evaluation. The study results appear to support the claim of the traditional medicine with respect to the efficacy of S. anacardium seed against inflammation and gout. Copyright © 2010. Published by Elsevier Ireland Ltd.

  14. Mycoplasma contamination revisited: mesenchymal stromal cells harboring Mycoplasma hyorhinis potently inhibit lymphocyte proliferation in vitro.

    Directory of Open Access Journals (Sweden)

    Severin Zinöcker

    Full Text Available BACKGROUND: Mesenchymal stromal cells (MSC have important immunomodulatory effects that can be exploited in the clinical setting, e.g. in patients suffering from graft-versus-host disease after allogeneic stem cell transplantation. In an experimental animal model, cultures of rat T lymphocytes were stimulated in vitro either with the mitogen Concanavalin A or with irradiated allogeneic cells in mixed lymphocyte reactions, the latter to simulate allo-immunogenic activation of transplanted T cells in vivo. This study investigated the inhibitory effects of rat bone marrow-derived MSC subsequently found to be infected with a common mycoplasma species (Mycoplasma hyorhinis on T cell activation in vitro and experimental graft-versus-host disease in vivo. PRINCIPAL FINDINGS: We found that M. hyorhinis infection increased the anti-proliferative effect of MSC dramatically, as measured by both radiometric and fluorimetric methods. Inhibition could not be explained solely by the well-known ability of mycoplasmas to degrade tritiated thymidine, but likely was the result of rapid dissemination of M. hyorhinis in the lymphocyte culture. CONCLUSIONS: This study demonstrates the potent inhibitory effect exerted by M. hyorhinis in standard lymphocyte proliferation assays in vitro. MSC are efficient vectors of mycoplasma infection, emphasizing the importance of monitoring cell cultures for contamination.

  15. Synthesis of xanthohumol analogues and discovery of potent thioredoxin reductase inhibitor as potential anticancer agent.

    Science.gov (United States)

    Zhang, Baoxin; Duan, Dongzhu; Ge, Chunpo; Yao, Juan; Liu, Yaping; Li, Xinming; Fang, Jianguo

    2015-02-26

    The selenoprotein thioredoxin reductases (TrxRs) are attractive targets for anticancer drugs development. Xanthohumol (Xn), a naturally occurring polyphenol chalcone from hops, has received increasing attention because of its multiple pharmacological activities. We synthesized Xn and its 43 analogues and discovered that compound 13n displayed the highest cytotoxicity toward HeLa cells (IC50 = 1.4 μM). Structure-activity relationship study indicates that the prenyl group is not necessary for cytotoxicity, and introducing electron-withdrawing group, especially on the meta-position, is favored. In addition, methylation of the phenoxyl groups generally improves the potency. Mechanistic study revealed that 13n selectively inhibits TrxR and induces reactive oxygen species and apoptosis in HeLa cells. Cells overexpressing TrxR are resistant to 13n insult, while knockdown of TrxR sensitizes cells to 13n treatment, highlighting the physiological significance of targeting TrxR by 13n. The clarification of the structural determinants for the potency would guide the design of novel potent molecules for future development.

  16. Design of a novel nucleoside analog as potent inhibitor of the NAD dependent deacetylase, SIRT2.

    Science.gov (United States)

    Sivaraman, Padavattan; Mattegunta, Suresh; Subbaraju, Gottumukkala V; Satyanarayana, Chava; Padmanabhan, Balasundaram

    2010-12-01

    Sirtuins (class III histone deacetylase) are evolutionarily conserved NAD(+)-dependent enzymes that catalyze the deacetylation of acetyl-lysine residues of histones and other target proteins. Because of their associations in various pathophysiological conditions, the identification of small molecule modulators has been of significant interest. In the present study, virtual screening was carried out with NCI Diversity Set II using crystal structure of hSIRT2 (PDB ID: 1J8F) as a model for the docking procedure to find potential compounds, which were then subjected to experimental tests for their in vitro SIRT2 inhibitory activity. One of the 40 compounds tested, NSC671136 (IUPAC name: 6-Acetyl-4-oxo-1,3-diphenyl-2-thioxo-1,2,3,4-tetrahydrothieno[2,3-d]pyrimidin-5-yl 2,4-dichlorobenzoate) has structurally unique scaffold, showed strong inhibitory activity towards SIRT2 with IC(50) of ~8.7 μM and to a lesser extent on SIRT1 activity. The reported compound is substantially potent compared to the published SIRT2 inhibitors and serves as an excellent base for future lead development.

  17. Neurologically Potent Molecules from Crataegus oxyacantha; Isolation, Anticholinesterase Inhibition, and Molecular Docking

    Directory of Open Access Journals (Sweden)

    Mumtaz Ali

    2017-06-01

    Full Text Available Crataegus oxyacantha is an important herbal supplement and famous for its antioxidant potential. The antioxidant in combination with anticholinesterase activity can be considered as an important target in the management of Alzheimer’s disease. The compounds isolated from C. oxyacantha were evaluated for cholinesterases inhibitory activity using Ellman’s assay with Galantamine as standard drug. Total of nine (1–9 compounds were isolated. Compounds 1 and 2 were isolated for the first time from natural source. Important natural products like β-Sitosterol-3-O-β-D-Glucopyranoside (3, lupeol (4, β-sitosterol (5, betulin (6, betulinic acid (7, oleanolic acid (8, and chrysin (9 have also been isolated from C. oxyacantha. Overall, all the compounds exhibited an overwhelming acetylcholinesterase (AChE inhibition potential in the range 5.22–44.47 μM. The compound 3 was prominent AChE inhibitor with IC50 value of 5.22 μM. Likewise, all the compounds were also potent in butyrylcholinesterase (BChE inhibitions with IC50s of up to 0.55–15.36 μM. All the compounds, except 3, were selective toward BChE. Mechanism of the inhibition of both the enzymes were further studied by docking procedures using Genetic Optimization for Ligand Docking suit v5.4.1. Furthermore, computational blood brain barrier prediction of the isolated compounds suggest that these are BBB+.

  18. Neurologically Potent Molecules from Crataegus oxyacantha; Isolation, Anticholinesterase Inhibition, and Molecular Docking.

    Science.gov (United States)

    Ali, Mumtaz; Muhammad, Sultan; Shah, Muhammad R; Khan, Ajmal; Rashid, Umer; Farooq, Umar; Ullah, Farhat; Sadiq, Abdul; Ayaz, Muhammad; Ali, Majid; Ahmad, Manzoor; Latif, Abdul

    2017-01-01

    Crataegus oxyacantha is an important herbal supplement and famous for its antioxidant potential. The antioxidant in combination with anticholinesterase activity can be considered as an important target in the management of Alzheimer's disease. The compounds isolated from C. oxyacantha were evaluated for cholinesterases inhibitory activity using Ellman's assay with Galantamine as standard drug. Total of nine (1-9) compounds were isolated. Compounds 1 and 2 were isolated for the first time from natural source. Important natural products like β-Sitosterol-3-O-β-D-Glucopyranoside (3), lupeol (4), β-sitosterol (5), betulin (6), betulinic acid (7), oleanolic acid (8), and chrysin (9) have also been isolated from C. oxyacantha. Overall, all the compounds exhibited an overwhelming acetylcholinesterase (AChE) inhibition potential in the range 5.22-44.47 μM. The compound 3 was prominent AChE inhibitor with IC50 value of 5.22 μM. Likewise, all the compounds were also potent in butyrylcholinesterase (BChE) inhibitions with IC50s of up to 0.55-15.36 μM. All the compounds, except 3, were selective toward BChE. Mechanism of the inhibition of both the enzymes were further studied by docking procedures using Genetic Optimization for Ligand Docking suit v5.4.1. Furthermore, computational blood brain barrier prediction of the isolated compounds suggest that these are BBB+.

  19. Chlorfenapyr, a Potent Alternative Insecticide of Phoxim To Control Bradysia odoriphaga (Diptera: Sciaridae).

    Science.gov (United States)

    Zhao, Yunhe; Wang, Qiuhong; Wang, Yao; Zhang, Zhengqun; Wei, Yan; Liu, Feng; Zhou, Chenggang; Mu, Wei

    2017-07-26

    Bradysia odoriphaga is the major pest affecting Chinese chive production, and in China, it has developed widespread resistance to organophosphorus insecticides. Chlorfenapyr is a promising pyrrole insecticide with a unique mechanism of action that does not confer cross-resistance to neurotoxic insecticides. However, the effect of chlorfenapyr on organophosphate-resistant B. odoriphaga is not well understood. The present study evaluated the potential of chlorfenapyr for the control of phoxim-resistant B. odoriphaga. The results showed that chlorfenapyr had significant insecticidal activity to B. odoriphaga in multiple developmental stages, and there were no significant differences in susceptibility between the field (phoxim-resistant) and laboratory (phoxim-susceptible) populations. The pot experiment and field trials confirmed the results of our laboratory bioassays. In the field trial, chlorfenapyr applied at 3.0, 6.0, or 12.0 kg of active ingredient (a.i.)/ha significantly decreased the number of B. odoriphaga and improved the yield compared to phoxim at 6.0 kg of a.i./ha and the control conditions. Moreover, the final residues of chlorfenapyr on plants were below the maximum residue limits (MRLs) as a result of its non-systemic activity. These results demonstrate that chlorfenapyr has potential as a potent alternative to phoxim for controlling B. odoriphaga.

  20. An armed oncolytic adenovirus system,ZD55-gene,demonstrating potent antitumoral efficacy

    Institute of Scientific and Technical Information of China (English)

    ZI LAI ZHANG; WEI GUO ZOU; CHUN XIA LUO; BING HUA LI; JIN HUI WANG; LAN YING SUN; QI JUN QIAN; XIN YUAN LIU

    2003-01-01

    ONYXONYX-015 is an attractive therapeutic adenovirus for cancer because it can selectively replicate in tumor cells and kill them.To date,clinicaltrials of this adenovirus have demonstrated marked safety but not potent enough when it was used alone.In this paper,we put forward a novel concept of Gene-Viro Therapy strategy and in this way,we constructed an armed therapeutic onco1ytic adenovirus system,ZD55-gene,whichis not only deleted of E1B 55-kD gene similar to ONYX-015,but also armed with foreign antitumor gene.ZD55-gene exhibited similar cytopathic effects and replication Kinetics to that of ONYX-015 in vitro.Importantly,the carried gene 1s expressed and the expression level can increase with the replication of virus.Consequently,a significant antitumoral efficacy was observed when ZD55-CD/5-FU was used as an example in nude mice with subcutaneous human SW620 colon cancer.Our data demonstratedthat ZD55-gene,which utilizingthe Gene-ViroTherapy strategy,is more efficacious than each individual component in vivo.

  1. The EDLL motif: a potent plant transcriptional activation domain from AP2/ERF transcription factors.

    Science.gov (United States)

    Tiwari, Shiv B; Belachew, Alemu; Ma, Siu Fong; Young, Melinda; Ade, Jules; Shen, Yu; Marion, Colleen M; Holtan, Hans E; Bailey, Adina; Stone, Jeffrey K; Edwards, Leslie; Wallace, Andreah D; Canales, Roger D; Adam, Luc; Ratcliffe, Oliver J; Repetti, Peter P

    2012-06-01

    In plants, the ERF/EREBP family of transcriptional regulators plays a key role in adaptation to various biotic and abiotic stresses. These proteins contain a conserved AP2 DNA-binding domain and several uncharacterized motifs. Here, we describe a short motif, termed 'EDLL', that is present in AtERF98/TDR1 and other clade members from the same AP2 sub-family. We show that the EDLL motif, which has a unique arrangement of acidic amino acids and hydrophobic leucines, functions as a strong activation domain. The motif is transferable to other proteins, and is active at both proximal and distal positions of target promoters. As such, the EDLL motif is able to partly overcome the repression conferred by the AtHB2 transcription factor, which contains an ERF-associated amphiphilic repression (EAR) motif. We further examined the activation potential of EDLL by analysis of the regulation of flowering time by NF-Y (nuclear factor Y) proteins. Genetic evidence indicates that NF-Y protein complexes potentiate the action of CONSTANS in regulation of flowering in Arabidopsis; we show that the transcriptional activation function of CONSTANS can be substituted by direct fusion of the EDLL activation motif to NF-YB subunits. The EDLL motif represents a potent plant activation domain that can be used as a tool to confer transcriptional activation potential to heterologous DNA-binding proteins.

  2. Neem oil (Azadirachta indica) nanoemulsion--a potent larvicidal agent against Culex quinquefasciatus.

    Science.gov (United States)

    Anjali, C H; Sharma, Yamini; Mukherjee, Amitava; Chandrasekaran, Natarajan

    2012-02-01

    Nanoemulsion composed of neem oil and non-ionic surfactant Tween 20, with a mean droplet size ranging from 31.03 to 251.43 nm, was formulated for various concentrations of the oil and surfactant. The larvicidal effect of the formulated neem oil nanoemulsion was checked against Culex quinquefasciatus. O/W emulsion was prepared using neem oil, Tween 20 and water. Nanoemulsion of 31.03 nm size was obtained at a 1:3 ratio of oil and surfactant, and it was found to be stable. The larger droplet size (251.43 nm) shifted to a smaller size of 31.03 nm with increase in the concentration of Tween 20. The viscosity of the nanoemulsion increased with increasing concentration of Tween 20. The lethal concentration (LC50) of the nanoemulsion against Cx. quinquefasciatus was checked for 1:0.30, 1:1.5 and 1:3 ratios of oil and surfactant respectively. The LC50 decreased with droplet size. The LC50 for the ratio 1:3 nanoemulsions was 11.75 mg L(-1). The formulated nanoemulsion of 31.03 nm size was found to be an effective larvicidal agent. This is the first time that a neem oil nanoemulsion of this droplet size has been reported. It may be a good choice as a potent and selective larvicide for Cx. quinquefasciatus. Copyright © 2011 Society of Chemical Industry.

  3. Iota-Carrageenan Is a Potent Inhibitor of Influenza A Virus Infection

    Science.gov (United States)

    Leibbrandt, Andreas; Meier, Christiane; König-Schuster, Marielle; Weinmüllner, Regina; Kalthoff, Donata; Pflugfelder, Bettina; Graf, Philipp; Frank-Gehrke, Britta; Beer, Martin; Fazekas, Tamas; Unger, Hermann; Prieschl-Grassauer, Eva; Grassauer, Andreas

    2010-01-01

    The 2009 flu pandemic and the appearance of oseltamivir-resistant H1N1 influenza strains highlight the need for treatment alternatives. One such option is the creation of a protective physical barrier in the nasal cavity. In vitro tests demonstrated that iota-carrageenan is a potent inhibitor of influenza A virus infection, most importantly also of pandemic H1N1/2009 in vitro. Consequently, we tested a commercially available nasal spray containing iota-carrageenan in an influenza A mouse infection model. Treatment of mice infected with a lethal dose of influenza A PR8/34 H1N1 virus with iota-carrageenan starting up to 48 hours post infection resulted in a strong protection of mice similar to mice treated with oseltamivir. Since alternative treatment options for influenza are rare, we conclude that the nasal spray containing iota-carrageenan is an alternative to neuraminidase inhibitors and should be tested for prevention and treatment of influenza A in clinical trials in humans. PMID:21179403

  4. Potent tetravalent replicon vaccines against botulinum neurotoxins using DNA-based Semliki Forest virus replicon vectors.

    Science.gov (United States)

    Yu, Yun-Zhou; Guo, Jin-Peng; An, Huai-Jie; Zhang, Shu-Ming; Wang, Shuang; Yu, Wei-Yuan; Sun, Zhi-Wei

    2013-05-07

    Human botulism is commonly associated with botulinum neurotoxin (BoNT) serotypes A, B, E and F. This suggests that the greatest need is for a tetravalent vaccine that provides protection against all four of these serotypes. In current study, we investigated the feasibility of generating several tetravalent vaccines that protected mice against the four serotypes. Firstly, monovalent replicon vaccine against BoNT induced better antibody response and protection than that of corresponding conventional DNA vaccine. Secondly, dual-expression DNA replicon pSCARSE/FHc or replicon particle VRP-E/FHc vaccine was well resistant to the challenge of BoNT/E and BoNT/F mixture as a combination vaccine composed of two monovalent replicon vaccines. Finally, the dual-expression DNA replicon or replicon particle tetravalent vaccine could simultaneously and effectively neutralize and protect the four BoNT serotypes. Protection correlated directly with serum ELISA titers and neutralization antibody levels to BoNTs. Therefore, replicon-based DNA or particle might be effective vector to develop BoNT vaccines, which might be more desirable for use in clinical application than the conventional DNA vaccines. Our studies demonstrate the utility of combining dual-expression DNA replicon or replicon particle vaccines into multi-agent formulations as potent tetravalent vaccines for eliciting protective responses to four serotypes of BoNTs.

  5. Development of ebsulfur analogues as potent antibacterials against methicillin-resistant Staphylococcus aureus.

    Science.gov (United States)

    Ngo, Huy X; Shrestha, Sanjib K; Green, Keith D; Garneau-Tsodikova, Sylvie

    2016-12-15

    Antibiotic resistance is a worldwide problem that needs to be addressed. Staphylococcus aureus is one of the dangerous "ESKAPE" pathogens that rapidly evolve and evade many current FDA-approved antibiotics. Thus, there is an urgent need for new anti-MRSA compounds. Ebselen (also known as 2-phenyl-1,2-benzisoselenazol-3(2H)-one) has shown promising activity in clinical trials for cerebral ischemia, bipolar disorder, and noise-induced hearing loss. Recently, there has been a renewed interest in exploring the antibacterial properties of ebselen. In this study, we synthesized an ebselen-inspired library of 33 compounds where the selenium atom has been replaced by sulfur (ebsulfur derivatives) and evaluated them against a panel of drug-sensitive and drug-resistant S. aureus and non-S. aureus strains. Within our library, we identified three outstanding analogues with potent activity against all S. aureus strains tested (MIC values mostly ⩽2μg/mL), and numerous additional ones with overall very good to good antibacterial activity (1-7.8μg/mL). We also characterized the time-kill analysis, anti-biofilm ability, hemolytic activity, mammalian cytotoxicity, membrane-disruption ability, and reactive oxygen species (ROS) production of some of these analogues.

  6. Crystal structure of LpxC from Pseudomonas aeruginosa complexed with the potent BB-78485 inhibitor

    Energy Technology Data Exchange (ETDEWEB)

    Mochalkin, Igor; Knafels, John D.; Lightle, Sandra (Pfizer)

    2008-04-02

    The cell wall in Gram-negative bacteria is surrounded by an outer membrane comprised of charged lipopolysaccharide (LPS) molecules that prevent entry of hydrophobic agents into the cell and protect the bacterium from many antibiotics. The hydrophobic anchor of LPS is lipid A, the biosynthesis of which is essential for bacterial growth and viability. UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine deacetylase (LpxC) is an essential zinc-dependant enzyme that catalyzes the conversion of UDP-3-O-(R-3-hydroxymyristoyl)-N-acetylglucosamine to UDP-3-O-(R-3-hydroxymyristoyl)glucosamine and acetate in the biosynthesis of lipid A, and for this reason, LpxC is an attractive target for antibacterial drug discovery. Here we disclose a 1.9 A resolution crystal structure of LpxC from Pseudomonas aeruginosa (paLpxC) in a complex with the potent BB-78485 inhibitor. To our knowledge, this is the first crystal structure of LpxC with a small-molecule inhibitor that shows antibacterial activity against a wide range of Gram-negative pathogens. Accordingly, this structure can provide important information for lead optimization and rational design of the effective small-molecule LpxC inhibitors for successful treatment of Gram-negative infections.

  7. Isolation and evaluation of potent Pseudomonas species for bioremediation of phorate in amended soil.

    Science.gov (United States)

    Jariyal, Monu; Gupta, V K; Jindal, Vikas; Mandal, Kousik

    2015-12-01

    Use of phorate as a broad spectrum pesticide in agricultural crops is finding disfavor due to persistence of both the principal compound as well as its toxic residues in soil. Three phorate utilizing bacterial species (Pseudomonas sp. strain Imbl 4.3, Pseudomonas sp. strain Imbl 5.1, Pseudomonas sp. strain Imbl 5.2) were isolated from field soils. Comparative phorate degradation analysis of these species in liquid cultures identified Pseudomonas sp. strain Imbl 5.1 to cause complete metabolization of phorate during seven days as compared to the other two species in 13 days. In soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil), Pseudomonas sp. strain Imbl 5.1 resulted in active metabolization of phorate by between 94.66% and 95.62% establishing the same to be a potent bacterium for significantly relieving soil from phorate residues. Metabolization of phorate to these phorate residues did not follow the first order kinetics. This study proves that Pseudomonas sp. strain Imbl 5.1 has huge potential for active bioremediation of phorate both in liquid cultures and agricultural soils.

  8. Protective capacity of Artemisia annua as a potent antioxidant remedy against free radical damage

    Institute of Scientific and Technical Information of China (English)

    Peter Nkachukwu Chukwurah; Ebiamadon Andi Brisibe; Aniefiok Ndubuisi Osuagwu; Tebekeme Okoko

    2014-01-01

    Objective: To evaluate the antioxidant capacity of four leaf-derived solvent extracts of Artemisiaannua Methods: A. annua leaves were extracted with four solvents (absolute ethanol, absolute methanol, 70% ethanol and 70% methanol), and extracts obtained studied by five complementaryin vitro antioxidant test systems using ascorbic acid (vitamin C) and rutin as standard references. Results: The extracts remarkably inhibited lipid peroxidation (79.81%-86.70%), and erythrocyte haemolysis (40.02%-49.91%). Their IC50 values for hydroxyl, nitric oxide and hydrogen peroxide radical scavenging activities ranged from 2.39-3.81 mg/mL (superior to the standards), 107.24-144.49 µg/mL and 28.53-53.20 µg/mL, respectively. 70% alcohol extracts generally showed better antioxidant activity than absolute alcohol extracts. (A. annua), a medicinal plant widely touted for its vast phyto-therapeutic potential. Conclusions: The results indicate that A. annua leaf extracts have potent antioxidant activities that would have beneficial effect on human health, and aqueous organic solvents are superior to the absolute counterparts in yielding extracts with better antioxidant potential.

  9. Identification of potent odorants in Chinese jasmine green tea scented with flowers of Jasminum sambac.

    Science.gov (United States)

    Ito, Yuriko; Sugimoto, Akio; Kakuda, Takami; Kubota, Kikue

    2002-08-14

    The odorants in Chinese jasmine green tea scented with jasmine flowers (Jasminum sambac) were separated from the infusion by adsorption to Porapak Q resin. Among the 66 compounds identified by GC and GC/MS, linalool (floral), methyl anthranilate (grape-like), 4-hexanolide (sweet), 4-nonanolide (sweet), (E)-2-hexenyl hexanoate (green), and 4-hydroxy-2,5-dimethyl-3(2H)-furanone (sweet) were extracted as potent odorants by an aroma extract dilution analysis and sensory analysis. The enantiomeric ratios of linalool in jasmine tea and Jasminum sambac were determined by a chiral analysis for the first time in this study: 81.6% ee and 100% ee for the (R)-(-)-configuration, respectively. The jasmine tea flavor could be closely duplicated by a model mixture containing these six compounds on the basis of a sensory analysis. The omission of methyl anthranilate and the replacement of (R)-(-)-linalool by (S)-(+)-linalool led to great changes in the odor of the model. These two compounds were determined to be the key odorants of the jasmine tea flavor.

  10. New-to-nature sophorose analog: a potent inducer for gene expression in Trichoderma reesei.

    Science.gov (United States)

    Huang, Tom Tao; Wages, John M

    2016-04-01

    Controlled hydrolysis of lactonic sophorolipids from Starmerella bombicola yields a previously undescribed sophorose analog that potently induces cellulase in Trichoderma reesei Rut-C30. Acid treatment of natural sophorolipids results in a mixture of monoacetylated, deacetylated, and diacetylated sophorolipids in acidic and lactonic forms. Isolation of the active components of the mixture, followed by structure determination by MS and NMR, reveals a new chemical entity, in which the lactone ring has been opened at the C-1' rather than at the C-4″ position of the sophorose moiety. This sophorose ester is resistant to degradation by the host and is at least 28 times more powerful an inducer than sophorose in shake-flask culture. Even at low concentrations (0.05 mM), the chemically modified sophorolipid effectively induces cellulase. With further improvements, this highly enabling technology can potentially reduce the cost of enzymes produced in T. reesei and can facilitate the rapid deployment of enzyme plants to support the nascent cellulosic biofuels and biochemicals industries. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Identification and characterization of potent small molecule inhibitor of hemorrhagic fever New World arenaviruses.

    Science.gov (United States)

    Bolken, Tove C; Laquerre, Sylvie; Zhang, Yuanming; Bailey, Thomas R; Pevear, Daniel C; Kickner, Shirley S; Sperzel, Lindsey E; Jones, Kevin F; Warren, Travis K; Amanda Lund, S; Kirkwood-Watts, Dana L; King, David S; Shurtleff, Amy C; Guttieri, Mary C; Deng, Yijun; Bleam, Maureen; Hruby, Dennis E

    2006-02-01

    Category A arenaviruses as defined by the National Institute of Allergy and Infectious Diseases (NIAID) are human pathogens that could be weaponized by bioterrorists. Many of these deadly viruses require biosafety level-4 (BSL-4) containment for all laboratory work, which limits traditional laboratory high-throughput screening (HTS) for identification of small molecule inhibitors. For those reasons, a related BSL-2 New World arenavirus, Tacaribe virus, 67-78% identical to Junín virus at the amino acid level, was used in a HTS campaign where approximately 400,000 small molecule compounds were screened in a Tacaribe virus-induced cytopathic effect (CPE) assay. Compounds identified in this screen showed antiviral activity and specificity against not only Tacaribe virus, but also the Category A New World arenaviruses (Junín, Machupo, and Guanarito). Drug resistant variants were isolated, suggesting that these compounds act through inhibition of a viral protein, the viral glycoprotein (GP2), and not through cellular toxicity mechanisms. A lead compound, ST-294, has been chosen for drug development. This potent and selective compound, with good bioavailability, demonstrated protective anti-viral efficacy in a Tacaribe mouse challenge model. This series of compounds represent a new class of inhibitors that may warrant further development for potential inclusion in a strategic stockpile.

  12. Insensitivity to pain induced by a potent selective closed-state Nav1.7 inhibitor

    Science.gov (United States)

    Flinspach, M.; Xu, Q.; Piekarz, A. D.; Fellows, R.; Hagan, R.; Gibbs, A.; Liu, Y.; Neff, R. A.; Freedman, J.; Eckert, W. A.; Zhou, M.; Bonesteel, R.; Pennington, M. W.; Eddinger, K. A.; Yaksh, T. L.; Hunter, M.; Swanson, R. V.; Wickenden, A. D.

    2017-01-01

    Pain places a devastating burden on patients and society and current pain therapeutics exhibit limitations in efficacy, unwanted side effects and the potential for drug abuse and diversion. Although genetic evidence has clearly demonstrated that the voltage-gated sodium channel, Nav1.7, is critical to pain sensation in mammals, pharmacological inhibitors of Nav1.7 have not yet fully recapitulated the dramatic analgesia observed in Nav1.7-null subjects. Using the tarantula venom-peptide ProTX-II as a scaffold, we engineered a library of over 1500 venom-derived peptides and identified JNJ63955918 as a potent, highly selective, closed-state Nav1.7 blocking peptide. Here we show that JNJ63955918 induces a pharmacological insensitivity to pain that closely recapitulates key features of the Nav1.7-null phenotype seen in mice and humans. Our findings demonstrate that a high degree of selectivity, coupled with a closed-state dependent mechanism of action is required for strong efficacy and indicate that peptides such as JNJ63955918 and other suitably optimized Nav1.7 inhibitors may represent viable non-opioid alternatives for the pharmacological treatment of severe pain. PMID:28045073

  13. Discovery of novel potent ΔF508-CFTR correctors that target the nucleotide binding domain.

    Science.gov (United States)

    Odolczyk, Norbert; Fritsch, Janine; Norez, Caroline; Servel, Nathalie; da Cunha, Melanie Faria; Bitam, Sara; Kupniewska, Anna; Wiszniewski, Ludovic; Colas, Julien; Tarnowski, Krzysztof; Tondelier, Danielle; Roldan, Ariel; Saussereau, Emilie L; Melin-Heschel, Patricia; Wieczorek, Grzegorz; Lukacs, Gergely L; Dadlez, Michal; Faure, Grazyna; Herrmann, Harald; Ollero, Mario; Becq, Frédéric; Zielenkiewicz, Piotr; Edelman, Aleksander

    2013-10-01

    The deletion of Phe508 (ΔF508) in the first nucleotide binding domain (NBD1) of CFTR is the most common mutation associated with cystic fibrosis. The ΔF508-CFTR mutant is recognized as improperly folded and targeted for proteasomal degradation. Based on molecular dynamics simulation results, we hypothesized that interaction between ΔF508-NBD1 and housekeeping proteins prevents ΔF508-CFTR delivery to the plasma membrane. Based on this assumption we applied structure-based virtual screening to identify new low-molecular-weight compounds that should bind to ΔF508-NBD1 and act as protein-protein interaction inhibitors. Using different functional assays for CFTR activity, we demonstrated that in silico-selected compounds induced functional expression of ΔF508-CFTR in transfected HeLa cells, human bronchial CF cells in primary culture, and in the nasal epithelium of homozygous ΔF508-CFTR mice. The proposed compounds disrupt keratin8-ΔF508-CFTR interaction in ΔF508-CFTR HeLa cells. Structural analysis of ΔF508-NBD1 in the presence of these compounds suggests their binding to NBD1. We conclude that our strategy leads to the discovery of new compounds that are among the most potent correctors of ΔF508-CFTR trafficking defect known to date.

  14. The Spider Venom Peptide Lycosin-II Has Potent Antimicrobial Activity against Clinically Isolated Bacteria

    Directory of Open Access Journals (Sweden)

    Yongjun Wang

    2016-04-01

    Full Text Available Antimicrobial peptides have been accepted as excellent candidates for developing novel antibiotics against drug-resistant bacteria. Recent studies indicate that spider venoms are the source for the identification of novel antimicrobial peptides. In the present study, we isolated and characterized an antibacterial peptide named lycosin-II from the venom of the spider Lycosa singoriensis. It contains 21 amino acid residue lacking cysteine residues and forms a typical linear amphipathic and cationic α-helical conformation. Lycosin-II displays potent bacteriostatic effect on the tested drug-resistant bacterial strains isolated from hospital patients, including multidrug-resistant A. baumannii, which has presented a huge challenge for the infection therapy. The inhibitory ability of lycosin-II might derive from its binding to cell membrane, because Mg2+ could compete with the binding sites to reduce the bacteriostatic potency of lycosin-II. Our data suggest that lycosin-II might be a lead in the development of novel antibiotics for curing drug-resistant bacterial infections.

  15. A novel polypeptide from shark cartilage with potent anti-angiogenic activity.

    Science.gov (United States)

    Zheng, Lanhong; Ling, Peixue; Wang, Zheng; Niu, Rongli; Hu, Chaoxin; Zhang, Tianmin; Lin, Xiukun

    2007-05-01

    Using guanidine-HCl extraction, acetone precipitation, ultra-filtration and chromatography, a novel polypeptide with potent anti-angiogenic activity was purified from cartilage of the shark, Prionace glauca. N-terminal amino acid sequence analysis and SDS-PAGE revealed that the substance is a novel polypeptide with MW 15500 (PG155). The anti-angiogenic effects of PG155 were evaluated using zebrafish embryos model in vivo. Treatment of the embryos with 20 microg/ml PG155 resulted in a significant reduction in the growth of subintestinal vessels (SIVs). A higher dose resulted in almost complete inhibition of SIV growth, as observed by endogenous alkaline phosphatase (EAP) staining assay. An in vitro transwell experiment revealed that the polypeptide inhibited vascular endothelial growth factor (VEGF) induced migration and tubulogenesis of human umbilical vein endothelial cells (HUVECs). Exposure of HUVECs in 20 microg/ml PG155 significantly decreased the density of migrated cells. Almost complete inhibition of cell migration was found when HUVECs were treated with 40-80 microg/ml PG155. PG155 (20 microg/ml) markedly inhibited the tube formation of HUVECs and a dose-dependent effect was also found when treatment of HUVECs with PG155 at the concentration from 20-160 microg/ml.

  16. Potent inhibition of feline coronaviruses with peptidyl compounds targeting coronavirus 3C-like protease.

    Science.gov (United States)

    Kim, Yunjeong; Mandadapu, Sivakoteswara Rao; Groutas, William C; Chang, Kyeong-Ok

    2013-02-01

    Feline coronavirus infection is common among domestic and exotic felid species and usually associated with mild or asymptomatic enteritis; however, feline infectious peritonitis (FIP) is a fatal disease of cats that is caused by systemic infection with a feline infectious peritonitis virus (FIPV), a variant of feline enteric coronavirus (FECV). Currently, there is no specific treatment approved for FIP despite the importance of FIP as the leading infectious cause of death in young cats. During the replication process, coronavirus produces viral polyproteins that are processed into mature proteins by viral proteases, the main protease (3C-like [3CL] protease) and the papain-like protease. Since the cleavages of viral polyproteins are an essential step for virus replication, blockage of viral protease is an attractive target for therapeutic intervention. Previously, we reported the generation of broad-spectrum peptidyl inhibitors against viruses that possess a 3C or 3CL protease. In this study, we further evaluated the antiviral effects of the peptidyl inhibitors against feline coronaviruses, and investigated the interaction between our protease inhibitor and a cathepsin B inhibitor, an entry blocker, against a feline coronavirus in cell culture. Herein we report that our compounds behave as reversible, competitive inhibitors of 3CL protease, potently inhibited the replication of feline coronaviruses (EC(50) in a nanomolar range) and, furthermore, combination of cathepsin B and 3CL protease inhibitors led to a strong synergistic interaction against feline coronaviruses in a cell culture system.

  17. Potent Dendritic Cell Vaccine Loaded with Latent Membrane Protein 2A(LMP2A)

    Institute of Scientific and Technical Information of China (English)

    Yun Chen; Kun Yao; Bing Wang; Jian Qing; Genyan Liu

    2008-01-01

    Epstein-Barr virus(EBV),a potential oncogenic herpesvirus,has been found to be associated with several malignancies.It's critical to elicit cellular immunity of the body to fight against EBV-associated tumor development.Using dendritic cells(DCs)loaded with latent membrane protein 2A(LMP2A)to elicit T cell response against tumor may be one of the most direct and safest immunotherapy approaches.The present study aimed to develop DCs-based cancer vaccine (DC loaded with LMP2A protein)and study its biological characteristics and immune functions.Purified LMP2A protein was extracted from a cell line L929/LMP2A stably expressing LMP2A.LMP2A could be loaded on DCs with no significant changes of the DC surface markers and cytomorphology.The percentage of DCs loaded with LMP2A was above 80%.LMP2A-loaded DCs markedly enhanced the proliferation of antigen-specific CD8+ T and CD4+ T cells by 3H-TdR incorporation assay.Besides, the specific cytotoxicity of the CTLs against LMP2A target cells was also significantly increased.These results indicated that DC-based vaccine loaded with virus antigen could elicit potent CTL response and provide a foundation for further study on the DC-based immunotherapy for nasopharygeal carcinoma and other EBV associated tumors.

  18. Highly fluorescent peptide nanoribbon impregnated with Sn-porphyrin as a potent DNA sensor.

    Science.gov (United States)

    Parayil, Sreenivasan Koliyat; Lee, Jooran; Yoon, Minjoong

    2013-05-01

    Highly fluorescent and thermo-stable peptide nanoribbons (PNRs) were fabricated by solvothermal self-assembly of a single peptide (D,D-diphenyl alanine peptides) with Sn-porphyrin (trans-dihydroxo[5,10,15,20-tetrakis(p-tolyl)porphyrinato] Sn(IV) (SnTTP(OH)2)). The structural characterization of the as-prepared nanoribbons was performed by transmitting electron microscopy (TEM), scanning electron microscopy (SEM) and atomic force microscopy (AFM), FT-IR and Raman spectroscopy, indicating that the lipophilic Sn-porphyrins are impregnated into the porous surface formed in the process of nanoribbon formation through intermolecular hydrogen bonding of the peptide main chains. Consequently the Sn-porphyrin-impregnated peptide nanoribbons (Sn-porphyrin-PNRs) exhibited typical UV-visible absorption spectrum of the monomer porphyrin with a red shifted Q-band, and their fluorescence quantum yield was observed to be enhanced compared to that of free Sn-porphyrin. Interestingly the fluorescence intensity and lifetimes of Sn-porphyrin-PNRs were selectively affected upon interaction with nucleotide base sequences of DNA while those of free Sn-porphyrins were not affected by binding with any of the DNA studied, indicating that DNA-induced changes in the fluorescence properties of Sn-porphyrin-PNRs are due to interaction between DNA and the PNR scaffold. These results imply that Sn-porphyrin-PNR will be useful as a potent fluorescent protein analogue and as a biocompatible DNA sensor.

  19. Rational Design of Potent Antagonists to the Human Growth Hormone Receptor

    Science.gov (United States)

    Fuh, Germaine; Cunningham, Brian C.; Fukunaga, Rikiro; Nagata, Shigekazu; Goeddel, David V.; Wells, James A.

    1992-06-01

    A hybrid receptor was constructed that contained the extracellular binding domain of the human growth hormone (hGH) receptor linked to the transmembrane and intracellular domains of the murine granulocyte colony-stimulating factor receptor. Addition of hGH to a myeloid leukemia cell line (FDC-P1) that expressed the hybrid receptor caused proliferation of these cells. The mechanism for signal transduction of the hybrid receptor required dimerization because monoclonal antibodies to the hGH receptor were agonists whereas their monovalent fragments were not. Receptor dimerization occurs sequentially-a receptor binds to site 1 on hGH, and then a second receptor molecule binds to site 2 on hGH. On the basis of this sequential mechanism, which may occur in many other cytokine receptors, inactive hGH analogs were designed that were potent antagonists to hGH-induced cell proliferation. Such antagonists could be useful for treating clinical conditions of hGH excess, such as acromegaly.

  20. The potent oncogene NPM-ALK mediates malignant transformation of normal human CD4(+) T lymphocytes.

    Science.gov (United States)

    Zhang, Qian; Wei, Fang; Wang, Hong Yi; Liu, Xiaobin; Roy, Darshan; Xiong, Qun-Bin; Jiang, Shuguang; Medvec, Andrew; Danet-Desnoyers, Gwenn; Watt, Christopher; Tomczak, Ewa; Kalos, Michael; Riley, James L; Wasik, Mariusz A

    2013-12-01

    With this study we have demonstrated that in vitro transduction of normal human CD4(+) T lymphocytes with NPM-ALK results in their malignant transformation. The transformed cells become immortalized and display morphology and immunophenotype characteristic of patient-derived anaplastic large-cell lymphomas. These unique features, which are strictly dependent on NPM-ALK activity and expression, include perpetual cell growth, proliferation, and survival; activation of the key signal transduction pathways STAT3 and mTORC1; and expression of CD30 (the hallmark of anaplastic large-cell lymphoma) and of immunosuppressive cytokine IL-10 and cell-surface protein PD-L1/CD274. Implantation of NPM-ALK-transformed CD4(+) T lymphocytes into immunodeficient mice resulted in formation of tumors indistinguishable from patients' anaplastic large-cell lymphomas. Our findings demonstrate that the key aspects of human carcinogenesis closely recapitulating the features of the native tumors can be faithfully reproduced in vitro when an appropriate oncogene is used to transform its natural target cells; this in turn points to the fundamental role in malignant cell transformation of potent oncogenes expressed in the relevant target cells. Such transformed cells should permit study of the early stages of carcinogenesis, and in particular the initial oncogene-host cell interactions. This experimental design could also be useful for studies of the effects of early therapeutic intervention and likely also the mechanisms of malignant progression.

  1. Iota-carrageenan is a potent inhibitor of influenza A virus infection.

    Directory of Open Access Journals (Sweden)

    Andreas Leibbrandt

    Full Text Available The 2009 flu pandemic and the appearance of oseltamivir-resistant H1N1 influenza strains highlight the need for treatment alternatives. One such option is the creation of a protective physical barrier in the nasal cavity. In vitro tests demonstrated that iota-carrageenan is a potent inhibitor of influenza A virus infection, most importantly also of pandemic H1N1/2009 in vitro. Consequently, we tested a commercially available nasal spray containing iota-carrageenan in an influenza A mouse infection model. Treatment of mice infected with a lethal dose of influenza A PR8/34 H1N1 virus with iota-carrageenan starting up to 48 hours post infection resulted in a strong protection of mice similar to mice treated with oseltamivir. Since alternative treatment options for influenza are rare, we conclude that the nasal spray containing iota-carrageenan is an alternative to neuraminidase inhibitors and should be tested for prevention and treatment of influenza A in clinical trials in humans.

  2. Potent diuretic effects of prednisone in heart failure patients with refractory diuretic resistance.

    Science.gov (United States)

    Liu, Chao; Liu, Gang; Zhou, Caixia; Ji, Zhenguo; Zhen, Yuzhi; Liu, Kunshen

    2007-09-01

    Refractory congestive heart failure (CHF) with diuretic resistance is life-threatening and predicts a short life expectancy. Glucocorticoids have been proven to have potent diuretic effects in animal studies; however, their efficacy in CHF patients with diuretic resistance is not known. Thirteen CHF patients with significant volume overload and diuretic resistance who failed to respond to a conventional sequential nephron blockade therapeutic strategy; that is, the coadministration of a thiazide (hydrochlorothiazide) and spironolactone, in combination with loop diuretics, were studied. Prednisone (1 mg/kg daily) was then added to standard care, with other medications unchanged, to determine diuretic efficacy in these CHF patients. Variables included body weight, urine volume, serum electrolytes and renal function. Adding prednisone resulted in striking diuresis with a mean (+/- SD) body weight reduction of 9.39+/-3.09 kg. Prednisone significantly decreased serum creatinine by 52.21+/-48.68 mumol/L and increased glomerular filtration rate by 33.63+/-15.87 mL/min/1.73 m(2) compared with baseline. All patients were discharged from hospital with improved clinical status and renal function, and 11 patients remained alive in the long term. The main side effect of prednisone appeared to be hyperglycemia in diabetic patients. The present study demonstrated that prednisone can rapidly eliminate volume overload and improve clinical status and renal function in CHF patients with diuretic resistance. Further prospective randomized clinical studies are warranted to confirm its clinical efficacy.

  3. Potent Antioxidative and UVB Protective Effect of Water Extract of Eclipta prostrata L.

    Directory of Open Access Journals (Sweden)

    Chin-Feng Chan

    2014-01-01

    Full Text Available Oxidative stress, including Ultraviolet (UV irradiation-induced skin damage, is involved in numerous diseases. This study demonstrates that water extract of Eclipta prostrata L. (WEP has a potent effect in scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH, superoxide radicals, and chelating ferrous ion, exhibiting IC50 values of 0.23 mg/mL, 0.48 mg/mL, and 1.25 mg/mL, respectively. The WEP total phenol content was 176.45 mg gallic acid equivalents (GAE/g sample. Chlorogenic acid, a component of the plant's active ingredients, was determined by HPLC and antioxidative assay. However, no caffeic acid, stigmasterol, or wedelolactone was present in WEP. WEP absorbs both UVA and UVB irradiation, and furthermore, the extract shows a dose-dependent response in the protection of HaCaT human keratinocytes and mouse fibroblasts 3T3 cells against UVB-induced cytotoxicity, which may result from a synergistic effect between chlorogenic acid and other active components present in WEP.

  4. Synthesis and biological assessment of simplified analogues of the potent microtubule stabilizer (+)-discodermolide.

    Science.gov (United States)

    Mínguez, José M; Kim, Sun-Young; Giuliano, Kenneth A; Balachandran, Raghavan; Madiraju, Charitha; Day, Billy W; Curran, Dennis P

    2003-07-31

    An efficient, convergent and stereocontrolled synthesis of simplified analogues of the potent antimitotic agent (+)-discodermolide has been achieved and several small libraries have been prepared. In all the libraries, the discodermolide methyl groups at C14 and C16 and the C7 hydroxy group were removed and the lactone was replaced by simple esters. Other modifications introduced in each series of analogues were related to C11, C17 and C19 of the natural product. Key elements of the synthetic strategy included (a) elaboration of the main subunits from a common intermediate and (b) fragment couplings using Wittig reactions to install the (Z)-olefins. Library components were analyzed for microtubule-stabilizing actions in vitro, for displacement of [3H]paclitaxel from its binding site on tubulin, for antiproliferative activity against human carcinoma cells, and for cell signaling and mitotic spindle alterations by a multiparameter fluorescence cell-based screening technique. The results show that even significant structural simplification can lead to analogues with actions related to microtubule targeting.

  5. A potent anti-complementary acylated sterol glucoside from Orostachys japonicus.

    Science.gov (United States)

    Yoon, Na Young; Min, Byung Sun; Lee, Hyeong Kyu; Park, Jong Cheol; Choi, Jae Sue

    2005-08-01

    In order to isolate substances that inhibit the hemolytic activity of human serum against erythrocytes, we have evaluated whole plants of the Orostachys japonicus species with regard to its anti-complement activity, and have identified its active principles following activity-guided isolation. A methanol extract of the O. japonicus, as well as its n-hexane soluble fraction, exhibited significant anti-complement activity on the complement system, which was expressed as total hemolytic activity. A bioassay-guided chromatographic separation of the constituents resulted in the isolation of three known compounds 1-3 from the active n-hexane fraction. The structure of these compounds were analyzed, and they were identified as hydroxyhopanone (1), beta-sitosteryl-3-O-beta-D-glucopyranosyl-6'-O-palmitate (2), and beta-sitosteryl-3-O-beta-D-glucopyranoside (3), respectively. Of these compounds, compound 2 exhibited potent anti-complement activity (IC50= 1.0 +/- 0.1 microM) on the classical pathway of the complement, as compared to tiliroside (IC50= 76.5 +/- 1.1 microM), which was used as a positive control. However, compounds 1 and 3 exhibited no activity in this system.

  6. Low-dose pterostilbene, but not resveratrol, is a potent neuromodulator in aging and Alzheimer's disease.

    Science.gov (United States)

    Chang, Jaewon; Rimando, Agnes; Pallas, Merce; Camins, Antoni; Porquet, David; Reeves, Jennifer; Shukitt-Hale, Barbara; Smith, Mark A; Joseph, James A; Casadesus, Gemma

    2012-09-01

    Recent studies have implicated resveratrol and pterostilbene, a resveratrol derivative, in the protection against age-related diseases including Alzheimer's disease (AD). However, the mechanism for the favorable effects of resveratrol in the brain remains unclear and information about direct cross-comparisons between these analogs is rare. As such, the purpose of this study was to compare the effectiveness of diet-achievable supplementation of resveratrol to that of pterostilbene at improving functional deficits and AD pathology in the SAMP8 mouse, a model of accelerated aging that is increasingly being validated as a model of sporadic and age-related AD. Furthermore we sought to determine the mechanism of action responsible for functional improvements observed by studying cellular stress, inflammation, and pathology markers known to be altered in AD. Two months of pterostilbene diet but not resveratrol significantly improved radial arm water maze function in SAMP8 compared with control-fed animals. Neither resveratrol nor pterostilbene increased sirtuin 1 (SIRT1) expression or downstream markers of sirtuin 1 activation. Importantly, markers of cellular stress, inflammation, and AD pathology were positively modulated by pterostilbene but not resveratrol and were associated with upregulation of peroxisome proliferator-activated receptor (PPAR) alpha expression. Taken together our findings indicate that at equivalent and diet-achievable doses pterostilbene is a more potent modulator of cognition and cellular stress than resveratrol, likely driven by increased peroxisome proliferator-activated receptor alpha expression and increased lipophilicity due to substitution of hydroxy with methoxy group in pterostilbene.

  7. Human heat shock protein-specific cytotoxic T lymphocytes display potent antitumour immunity in multiple myeloma

    Science.gov (United States)

    Li, Rong; Qian, Jianfei; Zhang, Wenhao; Fu, Weijun; Du, Juan; Jiang, Hua; Zhang, Hui; Zhang, Chunyang; Xi, Hao; Yi, Qing; Hou, Jian

    2014-01-01

    Tumour cell–derived heat shock proteins (HSPs) are used as vaccines for immunotherapy of cancer patients. However, it is proposed that the peptide chaperoned on HSPs, not HSPs themselves, elicited a potent immune response. Given that HSPs are highly expressed by most myeloma cells and vital to myeloma cell survival, we reasoned that HSPs themselves might be an ideal myeloma antigen. In the present study, we explored the feasibility of targeting HSPs themselves for treating multiple myeloma. We identified and chose HLA-A*0201-binding peptides from human HSPB1 (HSP27) and HSP90AA1 (HSP90), and confirmed their immunogenicity in HLA-A*0201 transgenic mice. Dendritic cells pulsed with HSPB1 and HSP90AA1 peptides were used to stimulate peripheral blood mononuclear cells from healthy volunteers and myeloma patients to generate HSP peptide-specific cytotoxic T lymphocytes (CTLs). HSP peptide-specific CTLs efficiently lysed HLA-A*0201+ myeloma cells (established cell lines and primary plasma cells) but not HLA-A*0201− myeloma cells in vitro, indicating that myeloma cells naturally express HSP peptides in the context of major histocompatibility complex class I molecules. More importantly, HSP peptide-specific CTLs effectively reduced tumour burden in the xenograft mouse model of myeloma. Our study clearly demonstrated that HSPs might be novel tumour antigens for immunotherapy of myeloma. PMID:24824351

  8. Discovery of Potent and Orally Bioavailable GPR40 Full Agonists Bearing Thiophen-2-ylpropanoic Acid Scaffold.

    Science.gov (United States)

    Li, He; Huang, Qi; Chen, Cheng; Xu, Bin; Wang, He-Yao; Long, Ya-Qiu

    2017-04-13

    The free fatty acid receptor GPR40 is predominantly expressed in pancreatic β-cells and enhances insulin secretion in a glucose dependent manner. Therefore, GPR40 agonists are possible novel insulin secretagogues with reduced or no risk of hypoglycemia for the treatment of type 2 diabetes mellitus (T2DM). Chemically and structurally diverse GPR40 agonists with high safety are pursued for the clinical development of GPR40-based pharmacotherapeutics. Herein we report our design and discovery of a new chemotype of GPR40 agonists free of the typical phenylpropanoic acid scaffold. The thiophen-2-ylpropanoic acid containing GPR40 modulators functioned as full agonists with high-efficacy response (Emax) and reduced lipophilicity. Significantly, the lead compound in this series, (R)-7k, exhibited more potent in vitro glucose-stimulated insulin secretion and in vivo glucose-lowering effects (10 mg/kg, po) than the GPR40 partial agonist TAK-875, which was once in phase III clinical trials, and high selectivity over the relevant receptors GPR120 and PPARγ.

  9. Potent inhibition of protein tyrosine phosphatases by copper complexes with multi-benzimidazole derivatives.

    Science.gov (United States)

    Li, Ying; Lu, Liping; Zhu, Miaoli; Wang, Qingming; Yuan, Caixia; Xing, Shu; Fu, Xueqi; Mei, Yuhua

    2011-12-01

    A series of copper complexes with multi-benzimidazole derivatives, including mono- and di-nuclear, were synthesized and characterized by Fourier transform IR spectroscopy, UV-Vis spectroscopy, elemental analysis, electrospray ionization mass spectrometry. The speciation of Cu/NTB in aqueous solution was investigated by potentiometric pH titrations. Their inhibitory effects against human protein tyrosine phosphatase 1B (PTP1B), T-cell protein tyrosine phosphatase (TCPTP), megakaryocyte protein tyrosine phosphatase 2 (PTP-MEG2), srchomology phosphatase 1 (SHP-1) and srchomology phosphatase 2 (SHP-2) were evaluated in vitro. The five copper complexes exhibit potent inhibition against PTP1B, TCPTP and PTP-MEG2 with almost same inhibitory effects with IC(50) at submicro molar level and about tenfold weaker inhibition versus SHP-1, but almost no inhibition against SHP-2. Kinetic analysis indicates that they are reversible competitive inhibitors of PTP1B. Fluorescence study on the interaction between PTP1B and complex 2 or 4 suggests that the complexes bind to PTP1B with the formation of a 1:1 complex. The binding constant are about 1.14 × 10(6) and 1.87 × 10(6) M(-1) at 310 K for 2 and 4, respectively.

  10. The Spider Venom Peptide Lycosin-II Has Potent Antimicrobial Activity against Clinically Isolated Bacteria

    Science.gov (United States)

    Wang, Yongjun; Wang, Ling; Yang, Huali; Xiao, Haoliang; Farooq, Athar; Liu, Zhonghua; Hu, Min; Shi, Xiaoliu

    2016-01-01

    Antimicrobial peptides have been accepted as excellent candidates for developing novel antibiotics against drug-resistant bacteria. Recent studies indicate that spider venoms are the source for the identification of novel antimicrobial peptides. In the present study, we isolated and characterized an antibacterial peptide named lycosin-II from the venom of the spider Lycosa singoriensis. It contains 21 amino acid residue lacking cysteine residues and forms a typical linear amphipathic and cationic α-helical conformation. Lycosin-II displays potent bacteriostatic effect on the tested drug-resistant bacterial strains isolated from hospital patients, including multidrug-resistant A. baumannii, which has presented a huge challenge for the infection therapy. The inhibitory ability of lycosin-II might derive from its binding to cell membrane, because Mg2+ could compete with the binding sites to reduce the bacteriostatic potency of lycosin-II. Our data suggest that lycosin-II might be a lead in the development of novel antibiotics for curing drug-resistant bacterial infections. PMID:27128941

  11. A ceramic drug delivery vehicle for oral administration of highly potent opioids.

    Science.gov (United States)

    Forsgren, Johan; Jämstorp, Erik; Bredenberg, Susanne; Engqvist, Håkan; Strømme, Maria

    2010-01-01

    Pellets composed of the ceramic material Halloysite and microcrystalline cellulose were synthesized with the aim of producing a drug delivery vehicle for sustained release of the opioid Fentanyl with low risk for dose dumping at oral intake of the highly potent drug. Drug release profiles of intact and crushed pellets, to simulate swallowing without or with chewing, in pH 6.8, pH 1, and in 48% ethanol were recorded in order to replicate the conditions in the small intestines, in the stomach, as well as cointake of the drug with alcohol. The drug release was analyzed by employing the Weibull equation, which showed that the release profiles were either governed by fickian diffusion (intact pellets in pH 6.8 and in ethanol) or by diffusion in a fractal or disordered pore network (intact pellets in pH 1 and crushed pellets in all solutions). A sustained release for approximately 3-4 h was obtained in all studied solutions from intact pellets, whereas crushed pellets released the drug content during approximately 2-3 h. The finding that a sustained release profile could be obtained both in alcohol and after crushing of the pellets, shows that the ceramic carrier under investigation, at least to some extent, hampers dose dumping, and may thus be a promising material in future developments of new opioid containing oral dosage forms.

  12. GDNF-transfected macrophages produce potent neuroprotective effects in Parkinson's disease mouse model.

    Directory of Open Access Journals (Sweden)

    Yuling Zhao

    Full Text Available The pathobiology of Parkinson's disease (PD is associated with the loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc projecting to the striatum. Currently, there are no treatments that can halt or reverse the course of PD; only palliative therapies, such as replacement strategies for missing neurotransmitters, exist. Thus, the successful brain delivery of neurotrophic factors that promote neuronal survival and reverse the disease progression is crucial. We demonstrated earlier systemically administered autologous macrophages can deliver nanoformulated antioxidant, catalase, to the SNpc providing potent anti-inflammatory effects in PD mouse models. Here we evaluated genetically-modified macrophages for active targeted brain delivery of glial cell-line derived neurotropic factor (GDNF. To capitalize on the beneficial properties afforded by alternatively activated macrophages, transfected with GDNF-encoded pDNA cells were further differentiated toward regenerative M2 phenotype. A systemic administration of GDNF-expressing macrophages significantly ameliorated neurodegeneration and neuroinflammation in PD mice. Behavioral studies confirmed neuroprotective effects of the macrophage-based drug delivery system. One of the suggested mechanisms of therapeutic effects is the release of exosomes containing the expressed neurotropic factor followed by the efficient GDNF transfer to target neurons. Such formulations can serve as a new technology based on cell-mediated active delivery of therapeutic proteins that attenuate and reverse progression of PD, and ultimately provide hope for those patients who are already significantly disabled by the disease.

  13. Potent, metabolically stable benzopyrimido-pyrrolo-oxazine-dione (BPO) CFTR inhibitors for polycystic kidney disease.

    Science.gov (United States)

    Snyder, David S; Tradtrantip, Lukmanee; Yao, Chenjuan; Kurth, Mark J; Verkman, A S

    2011-08-11

    We previously reported the discovery of pyrimido-pyrrolo-quinoxalinedione (PPQ) inhibitors of the cystic fibrosis transmembrane conductance regulator (CFTR) chloride channel and showed their efficacy in an organ culture model of polycystic kidney disease (PKD) (J. Med. Chem. 2009, 52, 6447-6455). Here, we report related benzopyrimido-pyrrolo-oxazinedione (BPO) CFTR inhibitors. To establish structure-activity relationships and select lead compound(s) with improved potency, metabolic stability, and aqueous solubility compared to the most potent prior compound 8 (PPQ-102, IC(50) ∼ 90 nM), we synthesized 16 PPQ analogues and 11 BPO analogues. The analogues were efficiently synthesized in 5-6 steps and 11-61% overall yield. Modification of 8 by bromine substitution at the 5-position of the furan ring, replacement of the secondary amine with an ether bridge, and carboxylation, gave 6-(5-bromofuran-2-yl)-7,9-dimethyl-8,10-dioxo-11-phenyl-7,8,9,10-tetrahydro-6H-benzo[b]pyrimido [4',5':3,4]pyrrolo [1,2-d][1,4]oxazine-2-carboxylic acid 42 (BPO-27), which fully inhibited CFTR with IC(50) ∼ 8 nM and, compared to 8, had >10-fold greater metabolic stability and much greater polarity/aqueous solubility. In an embryonic kidney culture model of PKD, 42 prevented cyst growth with IC(50) ∼ 100 nM. Benzopyrimido-pyrrolo-oxazinediones such as 42 are potential development candidates for antisecretory therapy of PKD.

  14. The indolylcoumarin COUFIN exhibits potent activity against renal carcinoma cells without affecting hematopoietic system.

    Science.gov (United States)

    Champelovier, Pierre; Barbier, Pascale; Daras, Etienne; Douillard, Soazig; Toussaint, Bertrand; Persoon, Virginie; Curri, Veronique; Peyrot, Vincent; Combes, Sebastien

    2014-01-01

    The present work describes the anticancer activity of a new indolylcoumarin named COUFIN and more specifically, its efficiency against clear cell renal carcinoma (CCRC). COUFIN inhibited microtubule formation and bound on tubulin to or near the colchicine site. In vitro, COUFIN showed potent anticancer activity on renal carcinoma cells (RCC) both in monolayer (2D culture) (IC50 of 88 ± 8 nM) and multicellular tumor spheroid (3D culture) (IC50 of 180 ± 20 nM). The compound blocked cell cycle transition at G2/M phase, induced a subsequent apoptotic process but did not modulate clonal growth of CFU-GM. On the other hand, the coumarin derivative decreased the activity of P-gp and BCRP but was not substrate for these ABC pumps. In vivo, the indolylcoumarin increased the survival rate after 3 weeks of treatment. Based on the present study, COUFIN was identified as a bifunctional molecule able to inhibit renal carcinoma cells proliferation without being effluxed by ABC proteins. Thus COUFIN could be a promising chemotherapeutic agent for treating tumor cells over-expressing efflux pumps and tumor cells irrigated by vessels lined with endothelial cells responsible of poor distribution of conventional anticancer agents.

  15. Demethoxycurcumin Is A Potent Inhibitor of P-Type ATPases from Diverse Kingdoms of Life.

    Science.gov (United States)

    Dao, Trong Tuan; Sehgal, Pankaj; Tung, Truong Thanh; Møller, Jesper Vuust; Nielsen, John; Palmgren, Michael; Christensen, Søren Brøgger; Fuglsang, Anja Thoe

    2016-01-01

    P-type ATPases catalyze the active transport of cations and phospholipids across biological membranes. Members of this large family are involved in a range of fundamental cellular processes. To date, a substantial number of P-type ATPase inhibitors have been characterized, some of which are used as drugs. In this work a library of natural compounds was screened and we first identified curcuminoids as plasma membrane H+-ATPases inhibitors in plant and fungal cells. We also found that some of the commercial curcumins contain several curcuminoids. Three of these were purified and, among the curcuminoids, demethoxycurcumin was the most potent inhibitor of all tested P-type ATPases from fungal (Pma1p; H+-ATPase), plant (AHA2; H+-ATPase) and animal (SERCA; Ca2+-ATPase) cells. All three curcuminoids acted as non-competitive antagonist to ATP and hence may bind to a highly conserved allosteric site of these pumps. Future research on biological effects of commercial preparations of curcumin should consider the heterogeneity of the material.

  16. Saururus cernuus lignans--potent small molecule inhibitors of hypoxia-inducible factor-1.

    Science.gov (United States)

    Hossain, Chowdhury Faiz; Kim, Yong-Pil; Baerson, Scott R; Zhang, Lei; Bruick, Richard K; Mohammed, Kaleem A; Agarwal, Ameeta K; Nagle, Dale G; Zhou, Yu-Dong

    2005-08-05

    Hypoxia-inducible factor-1 (HIF-1) represents an important tumor-selective therapeutic target for solid tumors. In search of novel small molecule HIF-1 inhibitors, 5400 natural product-rich extracts from plants, marine organisms, and microbes were examined for HIF-1 inhibitory activities using a cell-based reporter assay. Bioassay-guided fractionation and isolation, followed by structure elucidation, yielded three potent natural product-derived HIF-1 inhibitors and two structurally related inactive compounds. In a T47D cell-based reporter assay, manassantin B1, manassantin A, and 4-O-methylsaucerneol inhibited hypoxia-induced HIF-1 activation with IC50 values of 3, 3, and 20 nM, respectively. All three compounds are relatively hypoxia-specific inhibitors of HIF-1 activation, in comparison to other stimuli. The hypoxic induction of HIF-1 target genes CDKN1A, VEGF, and GLUT-1 were also inhibited. These compounds inhibit HIF-1 by blocking hypoxia-induced nuclear HIF-1alpha protein accumulation without affecting HIF-1alpha mRNA levels. In addition, preliminary structure-activity studies suggest specific structural requirements for this class of HIF-1 inhibitors.

  17. Saururus cernuus Lignans - Potent Small Molecule Inhibitors of Hypoxia-Inducible Factor-1

    Science.gov (United States)

    Hossain, Chowdhury Faiz; Kim, Yong-Pil; Baerson, Scott R.; Zhang, Lei; Bruick, Richard K.; Mohammed, Kaleem A.; Agarwal, Ameeta K.; Nagle, Dale G.; Zhou, Yu-Dong

    2010-01-01

    Hypoxia-inducible factor-1 (HIF-1) represents an important tumor-selective therapeutic target for solid tumors. In search of novel small molecule HIF-1 inhibitors, 5400 natural product-rich extracts from plants, marine organisms, and microbes were examined for HIF-1 inhibitory activities using a cell-based reporter assay. Bioassay-guided fractionation and isolation, followed by structure elucidation, yielded three potent natural product-derived HIF-1 inhibitors and two structurally related inactive compounds. In a T47D cell-based reporter assay, manassantin B1, manassantin A, and 4-O-methylsaucerneol inhibited hypoxia-induced HIF-1 activation with IC50 values of 3, 3, and 20 nM, respectively. All three compounds are relatively hypoxia-specific inhibitors of HIF-1 activation, in comparison to other stimuli. The hypoxic induction of HIF-1 target genes CDKN1A, VEGF and GLUT-1 were also inhibited. These compounds inhibit HIF-1 by blocking hypoxia-induced nuclear HIF-1α protein accumulation without affecting HIF-1α mRNA levels. In addition, preliminary structure-activity studies suggest specific structural requirements for this class of HIF-1 inhibitors. PMID:15967416

  18. Tetrodotoxin, an Extremely Potent Marine Neurotoxin: Distribution, Toxicity, Origin and Therapeutical Uses

    Directory of Open Access Journals (Sweden)

    Jorge Lago

    2015-10-01

    Full Text Available Tetrodotoxin (TTX is a potent neurotoxin responsible for many human intoxications and fatalities each year. The origin of TTX is unknown, but in the pufferfish, it seems to be produced by endosymbiotic bacteria that often seem to be passed down the food chain. The ingestion of contaminated pufferfish, considered the most delicious fish in Japan, is the usual route of toxicity. This neurotoxin, reported as a threat to human health in Asian countries, has spread to the Pacific and Mediterranean, due to the increase of temperature waters worldwide. TTX, for which there is no known antidote, inhibits sodium channel producing heart failure in many cases and consequently death. In Japan, a regulatory limit of 2 mg eq TTX/kg was established, although the restaurant preparation of “fugu” is strictly controlled by law and only chefs qualified are allowed to prepare the fish. Due to its paralysis effect, this neurotoxin could be used in the medical field as an analgesic to treat some cancer pains.

  19. Development of a recombinant antithrombin variant as a potent antidote to fondaparinux and other heparin derivatives.

    Science.gov (United States)

    Bianchini, Elsa P; Fazavana, Judicael; Picard, Veronique; Borgel, Delphine

    2011-02-10

    Heparin derivative-based therapy has evolved from unfractionated heparin (UFH) to low-molecular-weight heparins (LMWHs) and now fondaparinux, a synthetic pentasaccharide. Contrary to UFH or LMWHs, fondaparinux is not neutralized by protamine sulfate, and no antidote is available to counteract bleeding disorders associated with overdosing. To make the use of fondaparinux safer, we developed an antithrombin (AT) variant as a potent antidote to heparin derivatives. This variant (AT-N135Q-Pro394) combines 2 mutations: substitution of Asn135 by a Gln to remove a glycosylation site and increase affinity for heparins, and the insertion of a Pro between Arg393 and Ser394 to abolish its anticoagulant activity. As expected, AT-N135Q-Pro394 anticoagulant activity was almost abolished, and it exhibited a 3-fold increase in fondaparinux affinity. AT-N135Q-Pro394 was shown to reverse fondaparinux overdosing in vitro in a dose-dependent manner through a competitive process with plasma AT for fondaparinux binding. This antidote effect was also observed in vivo: administration of AT-N135Q-Pro394 in 2.5-fold molar excess versus plasma AT neutralized 86% of the anti-Xa activity within 5 minutes in mice treated with fondaparinux. These results clearly demonstrate that AT-N135Q-Pro394 can reverse the anticoagulant activity of fondaparinux and thus could be used as an antidote for this drug.

  20. Evaluation of indigenous potent mushroom growth promoting bacteria (MGPB) on Agaricus bisporus production.

    Science.gov (United States)

    Zarenejad, F; Yakhchali, B; Rasooli, I

    2012-01-01

    Mushrooms such as Agaricus bisporus, are cultivated for food worldwide. Fruit body initiation in Agaricus bisporus is a phase change from the vegetative to the reproductive stage which depends on the presence of a casing layer with particular physical, chemical and microbiological properties. The phase change is achieved practically by environmental manipulation and the presence of naturally occurring bacteria such as Pseuodomonas putida. In this study, 274 individual bacterial isolates were collected by screening the casing layer of 14 edible mushroom farms. The isolates were analysed with respect to biochemical properties, organic and inorganic phosphate solubilization, production of siderophore and growth in the presence of volatile compound of 1-octen-3-ol. It was found that approximately 97% of the strains were able to grow in the presence of 1-octen-3-ol and 36% were able to solubilize phosphorus. Among the isolates, 23 strains were selected as potent mushroom growth promoting bacteria (MGPB) for inoculation of the casing layer. Field experiments using these strains showed various promoting effects on production of mushroom. Finally, 2 strains (strains Bt4 and Ps7) showing the highest increase in A. bisporus production, were characterized as Pseuodomonas putida by molecular methods and identified as the best suited growth promoting inoculants for application in production farms for increasing the mushroom yield.

  1. Crystal Structure of HIV-1 Primary Receptor CD4 i Complex with a Potent Antiviral Antibody

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, M.M.; Hong, X.; Seaman, M.S.; Rits-Vollock, S.p Kao, C.Y.; Ho, D.D.; Chen, B.

    2010-06-18

    Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 {angstrom} resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121125) of D2, sitting on the opposite side of gp120 and MHC-II binding sites. No major conformational change in CD4 accompanies binding to ibalizumab. Both monovalent and bivalent forms of ibalizumab effectively block viral infection, suggesting that it does not need to crosslink CD4 to exert antiviral activity. While gp120-induced structural rearrangements in CD4 are probably minimal, CD4 structural rigidity is dispensable for ibalizumab inhibition. These results could guide CD4-based immunogen design and lead to a better understanding of HIV-1 entry.

  2. Crystal structure of HIV-1 primary receptor CD4 in complex with a potent antiviral antibody.

    Science.gov (United States)

    Freeman, Michael M; Seaman, Michael S; Rits-Volloch, Sophia; Hong, Xinguo; Kao, Chia-Ying; Ho, David D; Chen, Bing

    2010-12-08

    Ibalizumab is a humanized, anti-CD4 monoclonal antibody. It potently blocks HIV-1 infection and targets an epitope in the second domain of CD4 without interfering with immune functions mediated by interaction of CD4 with major histocompatibility complex (MHC) class II molecules. We report here the crystal structure of ibalizumab Fab fragment in complex with the first two domains (D1-D2) of CD4 at 2.2 Å resolution. Ibalizumab grips CD4 primarily by the BC-loop (residues 121-125) of D2, sitting on the opposite side of gp120 and MHC-II binding sites. No major conformational change in CD4 accompanies binding to ibalizumab. Both monovalent and bivalent forms of ibalizumab effectively block viral infection, suggesting that it does not need to crosslink CD4 to exert antiviral activity. While gp120-induced structural rearrangements in CD4 are probably minimal, CD4 structural rigidity is dispensable for ibalizumab inhibition. These results could guide CD4-based immunogen design and lead to a better understanding of HIV-1 entry.

  3. C3-halogenation of cytisine generates potent and efficacious nicotinic receptor agonists.

    Science.gov (United States)

    Abin-Carriquiry, J Andrés; Voutilainen, Merja H; Barik, Jacques; Cassels, Bruce K; Iturriaga-Vásquez, Patricio; Bermudez, Isabel; Durand, Claudia; Dajas, Federico; Wonnacott, Susan

    2006-04-24

    Neuronal nicotinic acetylcholine receptors subserve predominantly modulatory roles in the brain, making them attractive therapeutic targets. Natural products provide key leads in the quest for nicotinic receptor subtype-selective compounds. Cytisine, found in Leguminosae spp., binds with high affinity to alpha4beta2* nicotinic receptors. We have compared the effect of C3 and C5 halogenation of cytisine and methylcytisine (MCy) on their interaction with native rat nicotinic receptors. 3-Bromocytisine (3-BrCy) and 3-iodocytisine (3-ICy) exhibited increased binding affinity (especially at alpha7 nicotinic receptors; Ki approximately 0.1 microM) and functional potency, whereas C5-halogenation was detrimental. 3-BrCy and 3-ICy were more potent than cytisine at evoking [3H]dopamine release from striatal slices (EC50 approximately 11 nM), [3H]noradrenaline release from hippocampal slices (EC50 approximately 250 nM), increases in intracellular Ca2+ in PC12 cells and inward currents in Xenopus oocytes expressing human alpha3beta4 nicotinic receptor (EC50 approximately 2 microM). These compounds were also more efficacious than cytisine. C3-halogenation of cytisine is proposed to stabilize the open conformation of the nicotinic receptor but does not enhance subtype selectivity.

  4. Potent inhibition of Junín virus infection by interferon in murine cells.

    Science.gov (United States)

    Huang, Cheng; Walker, Aida G; Grant, Ashley M; Kolokoltsova, Olga A; Yun, Nadezhda E; Seregin, Alexey V; Paessler, Slobodan

    2014-06-01

    The new world arenavirus Junín virus (JUNV) is the causative agent of Argentine hemorrhagic fever, a lethal human infectious disease. Adult laboratory mice are generally resistant to peripheral infection by JUNV. The mechanism underlying the mouse resistance to JUNV infection is largely unknown. We have reported that interferon receptor knockout mice succumb to JUNV infection, indicating the critical role of interferon in restricting JUNV infection in mice. Here we report that the pathogenic and vaccine strains of JUNV were highly sensitive to interferon in murine primary cells. Treatment with low concentrations of interferon abrogated viral NP protein expression in murine cells. The replication of both JUNVs was enhanced in IRF3/IRF7 deficient cells. In addition, the vaccine strain of JUNV displayed impaired growth in primary murine cells. Our data suggested a direct and potent role of host interferon response in restricting JUNV replication in mice. The defect in viral growth for vaccine JUNV might also partially explain its attenuation in mice.

  5. Potent dengue virus neutralization by a therapeutic antibody with low monovalent affinity requires bivalent engagement.

    Directory of Open Access Journals (Sweden)

    Melissa A Edeling

    2014-04-01

    Full Text Available We recently described our most potently neutralizing monoclonal antibody, E106, which protected against lethal Dengue virus type 1 (DENV-1 infection in mice. To further understand its functional properties, we determined the crystal structure of E106 Fab in complex with domain III (DIII of DENV-1 envelope (E protein to 2.45 Å resolution. Analysis of the complex revealed a small antibody-antigen interface with the epitope on DIII composed of nine residues along the lateral ridge and A-strand regions. Despite strong virus neutralizing activity of E106 IgG at picomolar concentrations, E106 Fab exhibited a ∼20,000-fold decrease in virus neutralization and bound isolated DIII, E, or viral particles with only a micromolar monovalent affinity. In comparison, E106 IgG bound DENV-1 virions with nanomolar avidity. The E106 epitope appears readily accessible on virions, as neutralization was largely temperature-independent. Collectively, our data suggest that E106 neutralizes DENV-1 infection through bivalent engagement of adjacent DIII subunits on a single virion. The isolation of anti-flavivirus antibodies that require bivalent binding to inhibit infection efficiently may be a rare event due to the unique icosahedral arrangement of envelope proteins on the virion surface.

  6. Aspartic acid based nucleoside phosphoramidate prodrugs as potent inhibitors of hepatitis C virus replication.

    Science.gov (United States)

    Maiti, Munmun; Maiti, Mohitosh; Rozenski, Jef; De Jonghe, Steven; Herdewijn, Piet

    2015-05-14

    In view of a persistent threat to mankind, the development of nucleotide-based prodrugs against hepatitis C virus (HCV) is considered as a constant effort in many medicinal chemistry groups. In an attempt to identify novel nucleoside phosphoramidate analogues for improving the anti-HCV activity, we have explored, for the first time, aspartic acid (Asp) and iminodiacetic acid (IDA) esters as amidate counterparts by considering three 2'-C-methyl containing nucleosides, 2'-C-Me-cytidine, 2'-C-Me-uridine and 2'-C-Me-2'-fluoro-uridine. Synthesis of these analogues required protection for the vicinal diol functionality of the sugar moiety and the amino group of the cytidine nucleoside to regioselectively perform phosphorylation reaction at the 5'-hydroxyl group. Anti-HCV data demonstrate that the Asp-based phosphoramidates are ∼550 fold more potent than the parent nucleosides. The inhibitory activity of the Asp-ProTides was higher than the Ala-ProTides, suggesting that Asp would be a potential amino acid candidate to be considered for developing novel antiviral prodrugs.

  7. Synthesis of giant globular multivalent glycofullerenes as potent inhibitors in a model of Ebola virus infection

    Science.gov (United States)

    Muñoz, Antonio; Sigwalt, David; Illescas, Beatriz M.; Luczkowiak, Joanna; Rodríguez-Pérez, Laura; Nierengarten, Iwona; Holler, Michel; Remy, Jean-Serge; Buffet, Kevin; Vincent, Stéphane P.; Rojo, Javier; Delgado, Rafael; Nierengarten, Jean-François; Martín, Nazario

    2016-01-01

    The use of multivalent carbohydrate compounds to block cell-surface lectin receptors is a promising strategy to inhibit the entry of pathogens into cells and could lead to the discovery of novel antiviral agents. One of the main problems with this approach, however, is that it is difficult to make compounds of an adequate size and multivalency to mimic natural systems such as viruses. Hexakis adducts of [60]fullerene are useful building blocks in this regard because they maintain a globular shape at the same time as allowing control over the size and multivalency. Here we report water-soluble tridecafullerenes decorated with 120 peripheral carbohydrate subunits, so-called ‘superballs’, that can be synthesized efficiently from hexakis adducts of [60]fullerene in one step by using copper-catalysed azide-alkyne cycloaddition click chemistry. Infection assays show that these superballs are potent inhibitors of cell infection by an artificial Ebola virus with half-maximum inhibitory concentrations in the subnanomolar range.

  8. Potent odorants characterize the aroma quality of leaves and stalks in raw and boiled celery.

    Science.gov (United States)

    Kurobayashi, Yoshiko; Kouno, Emi; Fujita, Akira; Morimitsu, Yasujiro; Kubota, Kikue

    2006-04-01

    The raw and boiled odors of celery leaves and stalks were investigated. Among 12 compounds identified as potent odorants, 3-n-butylphthalide 1, sedanenolide 2, and trans- and cis-sedanolides 3, 4 were assessed to be most contributive to the overall odor of celery. These three phthalides, (3E,5Z)-1,3,5-undecatriene, myrcene, and (E)-2-nonenal were common to both raw and boiled materials. Two compounds, ((Z)-3-hexenal and (Z)-3-hexenol), were dominant in raw materials and four compounds, (2-methylbutanoic acid, sotolon, beta-damascenone, and beta-ionone), were dominant in boiled materials. Sensory evaluations were performed on natural celery odor and a series of reconstructed model aromas by assigning each intensity ratings for a set of seven odor qualities which aptly describe the odors of raw and boiled celery. According to the evaluation results, six common components contributed to the moderate odor of raw celery, two components dominant in raw materials enhanced the raw celery character, and four components dominant in boiled materials reduced the raw celery character and enhanced the boiled celery character. It was clarified that boiling-induced changes in celery odor were not affected by the amounts of phthalides, but by thermally generated compounds such as sotolon, beta-damascenone, and beta-ionone, which reduce the "green spicy" note.

  9. Recent progress on C-4-modified podophyllotoxin analogs as potent antitumor agents.

    Science.gov (United States)

    Liu, Ying-Qian; Tian, Jing; Qian, Keduo; Zhao, Xiao-Bo; Morris-Natschke, Susan L; Yang, Liu; Nan, Xiang; Tian, Xuan; Lee, Kuo-Hsiung

    2015-01-01

    Podophyllotoxin (PPT), as well as its congeners and derivatives, exhibits pronounced biological activities, especially antineoplastic effects. Its strong inhibitory effect on tumor cell growth led to the development of three of the most highly prescribed anticancer drugs in the world, etoposide, teniposide, and the water-soluble prodrug etoposide phosphate. Their clinical success as well as intriguing mechanism of action stimulated great interest in further modification of PPT for better antitumor activity. The C-4 position has been a major target for structural derivatization aimed at either producing more potent compounds or overcoming drug resistance. Accordingly, numerous PPT derivatives have been prepared via hemisynthesis and important structure-activity relationship (SAR) correlations have been identified. Several resulting compounds, including GL-331, TOP-53, and NK611, reached clinical trials. Some excellent reviews on the distribution, sources, applications, synthesis, and SAR of PPT have been published. This review focuses on a second generation of new etoposide-related drugs and provides detailed coverage of the current status and recent development of C-4-modified PPT analogs as anticancer clinical trial candidates.

  10. Ficus racemosa Stem Bark Extract: A Potent Antioxidant and a Probable Natural Radioprotector.

    Science.gov (United States)

    Veerapur, V P; Prabhakar, K R; Parihar, Vipan Kumar; Kandadi, Machendar Reddy; Ramakrishana, S; Mishra, B; Satish Rao, B S; Srinivasan, K K; Priyadarsini, K I; Unnikrishnan, M K

    2009-09-01

    Ethanol extract (FRE) and water extract (FRW) of Ficus racemosa (family: Moraceae) were subjected to free radical scavenging both by steady state and time resolved methods such as nanosecond pulse radiolysis and stopped-flow spectrophotometric analyses. FRE exhibited significantly higher steady state antioxidant activity than FRW. FRE exhibited concentration dependent DPPH, ABTS(*-), hydroxyl radical and superoxide radical scavenging and inhibition of lipid peroxidation with IC(50) comparable with tested standard compounds. In vitro radioprotective potential of FRE was studied using micronucleus assay in irradiated Chinese hamster lung fibroblast cells (V79). Pretreatment with different doses of FRE 1h prior to 2 Gy gamma-radiation resulted in a significant (P FRE. The radioprotection was found to be significant (P FRE (20 mug/ml) 1 h prior to 0.5, 1, 2, 3 and 4 Gy gamma-irradiation compared to the respective radiation controls. The cytokinesis-block proliferative index indicated that FRE does not alter radiation induced cell cycle delay. Based on all these results we conclude that the ethanol extract of F. racemosa acts as a potent antioxidant and a probable radioprotector.

  11. Ficus racemosa Stem Bark Extract: A Potent Antioxidant and a Probable Natural Radioprotector

    Directory of Open Access Journals (Sweden)

    V. P. Veerapur

    2009-01-01

    Full Text Available Ethanol extract (FRE and water extract (FRW of Ficus racemosa (family: Moraceae were subjected to free radical scavenging both by steady state and time resolved methods such as nanosecond pulse radiolysis and stopped-flow spectrophotometric analyses. FRE exhibited significantly higher steady state antioxidant activity than FRW. FRE exhibited concentration dependent DPPH, ABTS•-, hydroxyl radical and superoxide radical scavenging and inhibition of lipid peroxidation with IC50 comparable with tested standard compounds. In vitro radioprotective potential of FRE was studied using micronucleus assay in irradiated Chinese hamster lung fibroblast cells (V79. Pretreatment with different doses of FRE 1h prior to 2 Gy γ-radiation resulted in a significant (P < 0.001 decrease in the percentage of micronucleated binuclear V79 cells. Maximum radioprotection was observed at 20 μg/ml of FRE. The radioprotection was found to be significant (P < 0.01 when cells were treated with optimum dose of FRE (20 μg/ml 1 h prior to 0.5, 1, 2, 3 and 4 Gy γ-irradiation compared to the respective radiation controls. The cytokinesis-block proliferative index indicated that FRE does not alter radiation induced cell cycle delay. Based on all these results we conclude that the ethanol extract of F. racemosa acts as a potent antioxidant and a probable radioprotector.

  12. Rapid discovery of potent siRNA-containing lipid nanoparticles enabled by controlled microfluidic formulation.

    Science.gov (United States)

    Chen, Delai; Love, Kevin T; Chen, Yi; Eltoukhy, Ahmed A; Kastrup, Christian; Sahay, Gaurav; Jeon, Alvin; Dong, Yizhou; Whitehead, Kathryn A; Anderson, Daniel G

    2012-04-25

    The discovery of potent new materials for in vivo delivery of nucleic acids depends upon successful formulation of the active molecules into a dosage form suitable for the physiological environment. Because of the inefficiencies of current formulation methods, materials are usually first evaluated for in vitro delivery efficacy as simple ionic complexes with the nucleic acids (lipoplexes). The predictive value of such assays, however, has never been systematically studied. Here, for the first time, by developing a microfluidic method that allowed the rapid preparation of high-quality siRNA-containing lipid nanoparticles (LNPs) for a large number of materials, we have shown that gene silencing assays employing lipoplexes result in a high rate of false negatives (~90%) that can largely be avoided through formulation. Seven novel materials with in vivo gene silencing potencies of >90% at a dose of 1.0 mg/kg in mice were discovered. This method will facilitate the discovery of next-generation reagents for LNP-mediated nucleic acid delivery.

  13. Helminth Products Potently Modulate Experimental Autoimmune Encephalomyelitis by Downregulating Neuroinflammation and Promoting a Suppressive Microenvironment

    Directory of Open Access Journals (Sweden)

    Alberto N. Peón

    2017-01-01

    Full Text Available A negative correlation between the geographical distribution of autoimmune diseases and helminth infections has been largely associated in the last few years with a possible role for such type of parasites in the regulation of inflammatory diseases, suggesting new pathways for drug development. However, few helminth-derived immunomodulators have been tested in experimental autoimmune encephalomyelitis (EAE, an animal model of the human disease multiple sclerosis (MS. The immunomodulatory activities of Taenia crassiceps excreted/secreted products (TcES that may suppress EAE development were sought for. Interestingly, it was discovered that TcES was able to suppress EAE development with more potency than dexamethasone; moreover, TcES treatment was still effective even when inoculated at later stages after the onset of EAE. Importantly, the TcES treatment was able to induce a range of Th2-type cytokines, while suppressing Th1 and Th17 responses. Both the polyclonal and the antigen-specific proliferative responses of lymphocytes were also inhibited in EAE-ill mice receiving TcES in association with a potent recruitment of suppressor cell populations. Peritoneal inoculation of TcES was able to direct the normal inflammatory cell traffic to the site of injection, thus modulating CNS infiltration, which may work along with Th2 immune polarization and lymphocyte activation impairment to downregulate EAE development.

  14. Mirror-image organometallic osmium arene iminopyridine halido complexes exhibit similar potent anticancer activity.

    Science.gov (United States)

    Fu, Ying; Soni, Rina; Romero, María J; Pizarro, Ana M; Salassa, Luca; Clarkson, Guy J; Hearn, Jessica M; Habtemariam, Abraha; Wills, Martin; Sadler, Peter J

    2013-11-04

    Four chiral Os(II) arene anticancer complexes have been isolated by fractional crystallization. The two iodido complexes, (S(Os),S(C))-[Os(η(6)-p-cym)(ImpyMe)I]PF6 (complex 2, (S)-ImpyMe: N-(2-pyridylmethylene)-(S)-1-phenylethylamine) and (R(Os),R(C))-[Os(η(6)-p-cym)(ImpyMe)I]PF6 (complex 4, (R)-ImpyMe: N-(2-pyridylmethylene)-(R)-1-phenylethylamine), showed higher anticancer activity (lower IC50 values) towards A2780 human ovarian cancer cells than cisplatin and were more active than the two chlorido derivatives, (S(Os),S(C))-[Os(η(6)-p-cym)(ImpyMe)Cl]PF6, 1, and (R(Os),R(C))-[Os(η(6)-p-cym)(ImpyMe)Cl]PF6, 3. The two iodido complexes were evaluated in the National Cancer Institute 60-cell-line screen, by using the COMPARE algorithm. This showed that the two potent iodido complexes, 2 (NSC: D-758116/1) and 4 (NSC: D-758118/1), share surprisingly similar cancer cell selectivity patterns with the anti-microtubule drug, vinblastine sulfate. However, no direct effect on tubulin polymerization was found for 2 and 4, an observation that appears to indicate a novel mechanism of action. In addition, complexes 2 and 4 demonstrated potential as transfer-hydrogenation catalysts for imine reduction.

  15. The production and detoxification of a potent cytotoxin, nitric oxide, by pathogenic enteric bacteria.

    Science.gov (United States)

    Arkenberg, Anke; Runkel, Sebastian; Richardson, David J; Rowley, Gary

    2011-12-01

    The nitrogen cycle is based on several redox reactions that are mainly accomplished by prokaryotic organisms, some archaea and a few eukaryotes, which use these reactions for assimilatory, dissimilatory or respiratory purposes. One group is the Enterobacteriaceae family of Gammaproteobacteria, which have their natural habitats in soil, marine environments or the intestines of humans and other warm-blooded animals. Some of the genera are pathogenic and usually associated with intestinal infections. Our body possesses several physical and chemical defence mechanisms to prevent pathogenic enteric bacteria from invading the gastrointestinal tract. One response of the innate immune system is to activate macrophages, which produce the potent cytotoxin nitric oxide (NO). However, some pathogens have evolved the ability to detoxify NO to less toxic compounds, such as the neuropharmacological agent and greenhouse gas nitrous oxide (N₂O), which enables them to overcome the host's attack. The same mechanisms may be used by bacteria producing NO endogenously as a by-product of anaerobic nitrate respiration. In the present review, we provide a brief introduction into the NO detoxification mechanisms of two members of the Enterobacteriaceae family: Escherichia coli and Salmonella enterica serovar Typhimurium. These are discussed as comparative non-pathogenic and pathogenic model systems in order to investigate the importance of detoxifying NO and producing N₂O for the pathogenicity of enteric bacteria.

  16. Nifuroxazide exerts potent anti-tumor and anti-metastasis activity in melanoma.

    Science.gov (United States)

    Zhu, Yongxia; Ye, Tinghong; Yu, Xi; Lei, Qian; Yang, Fangfang; Xia, Yong; Song, Xuejiao; Liu, Li; Deng, Hongxia; Gao, Tiantao; Peng, Cuiting; Zuo, Weiqiong; Xiong, Ying; Zhang, Lidan; Wang, Ningyu; Zhao, Lifeng; Xie, Yongmei; Yu, Luoting; Wei, Yuquan

    2016-02-02

    Melanoma is a highly malignant neoplasm of melanocytes with considerable metastatic potential and drug resistance, explaining the need for new candidates that inhibit tumor growth and metastasis. The signal transducer and activator of the transcription 3 (Stat3) signaling pathway plays an important role in melanoma and has been validated as promising anticancer target for melanoma therapy. In this study, nifuroxazide, an antidiarrheal agent identified as an inhibitor of Stat3, was evaluated for its anti-melanoma activity in vitro and in vivo. It had potent anti-proliferative activity against various melanoma cell lines and could induce G2/M phase arrest and cell apoptosis. Moreover, nifuroxazide markedly impaired melanoma cell migration and invasion by down-regulating phosphorylated-Src, phosphorylated-FAK, and expression of matrix metalloproteinase (MMP) -2, MMP-9 and vimentin. It also significantly inhibited tumor growth without obvious side effects in the A375-bearing mice model by inducing apoptosis and reducing cell proliferation and metastasis. Notably, nifuroxazide significantly inhibited pulmonary metastases, which might be associated with the decrease of myeloid-derived suppressor cells (MDSCs). These findings suggested that nifuroxazide might be a potential agent for inhibiting the growth and metastasis of melanoma.

  17. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    CHEN JinCan; QIAN Li; SHEN Yong; CHEN LanMei; ZHENG KangCheng

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis.A new scheme deter-mining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-1) was suggested and suc-cessfully used.In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (IgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds.The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively.It indicates that this model has a significantly statistical quality and an excellent prediction ability.Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  18. A QSAR study and molecular design of benzothiazole derivatives as potent anticancer agents

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A quantitative structure-activity relationship (QSAR) of a series of benzothiazole derivatives showing a potent and selective cytotoxicity against a tumorigenic cell line has been studied by using the density functional theory (DFT), molecular mechanics (MM+) and statistical methods, and the QSAR equation was established via a correlation analysis and a stepwise regression analysis. A new scheme determining outliers by "leave-one-out" (LOO) cross-validation coefficient (q2n-i) was suggested and successfully used. In the established optimal equation (excluding two outliers), the steric parameter (MRR) and the net charge (QFR) of the first atom of the substituent (R), as well as the square of hydrophobic parameter (lgP)2 of the whole molecule, are the main independent factors contributing to the anticancer activities of the compounds. The fitting correlation coefficient (R2) and the cross-validation coefficient (q2) values are 0.883 and 0.797, respectively. It indicates that this model has a significantly statistical quality and an excellent prediction ability. Based on the QSAR studies, 4 new compounds with high predicted anticancer activities have been theoretically designed and they are expected to be confirmed experimentally.

  19. Potent and selective Bruton's tyrosine kinase inhibitors: discovery of GDC-0834.

    Science.gov (United States)

    Young, Wendy B; Barbosa, James; Blomgren, Peter; Bremer, Meire C; Crawford, James J; Dambach, Donna; Gallion, Steve; Hymowitz, Sarah G; Kropf, Jeffrey E; Lee, Seung H; Liu, Lichuan; Lubach, Joseph W; Macaluso, Jen; Maciejewski, Pat; Maurer, Brigitte; Mitchell, Scott A; Ortwine, Daniel F; Di Paolo, Julie; Reif, Karin; Scheerens, Heleen; Schmitt, Aaron; Sowell, C Gregory; Wang, Xiaojing; Wong, Harvey; Xiong, Jin-Ming; Xu, Jianjun; Zhao, Zhongdong; Currie, Kevin S

    2015-03-15

    SAR studies focused on improving the pharmacokinetic (PK) properties of the previously reported potent and selective Btk inhibitor CGI-1746 (1) resulted in the clinical candidate GDC-0834 (2), which retained the potency and selectivity of CGI-1746, but with much improved PK in preclinical animal models. Structure based design efforts drove this work as modifications to 1 were investigated at both the solvent exposed region as well as 'H3 binding pocket'. However, in vitro metabolic evaluation of 2 revealed a non CYP-mediated metabolic process that was more prevalent in human than preclinical species (mouse, rat, dog, cyno), leading to a high-level of uncertainly in predicting human pharmacokinetics. Due to its promising potency, selectivity, and preclinical efficacy, a single dose IND was filed and 2 was taken in to a single dose phase I trial in healthy volunteers to quickly evaluate the human pharmacokinetics. In human, 2 was found to be highly labile at the exo-cyclic amide bond that links the tetrahydrobenzothiophene moiety to the central aniline ring, resulting in insufficient parent drug exposure. This information informed the back-up program and discovery of improved inhibitors. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Interleukin-10 paradox: A potent immunoregulatory cytokine that has been difficult to harness for immunotherapy

    Science.gov (United States)

    Saxena, Ankit; Khosraviani, Sam; Noel, Sanjeev; Mohan, Divya; Donner, Thomas; Hamad, Abdel Rahim A.

    2015-01-01

    Interleukin-10 (IL-10) is arguably the most potent anti-inflammatory cytokine. It is produced by almost all the innate and adaptive immune cells. These cells also serve as its targets, indicating that IL-10 secretion and action is highly regulated and perhaps compartmentalized. Consistent with this notion, various efforts directed at systemic administration of IL-10 to modulate autoimmune diseases (type 1 diabetes, multiple sclerosis, rheumatoid arthritis, psoriasis) have produced conflicting and largely inconsequential effects. On the other hand, IL-10 can promote humoral immune responses, enhancing class II expression on B cells and inducing immunoglobulin (Ig) production. Consequently, the high IL-10 level in systemic lupus erythematosus (SLE) patients is considered pathogenic and its blockade ameliorates the disease. In this perspective, we review preclinical findings and results of recent clinical studies using exogenous IL-10 to treat the aforementioned autoimmune diseases. In addition, given the limited success of IL-10 supplementation, we suggest that future studies should be expanded beyond modulating the delivery modes to include developing new strategies to protect and replenish the endogenous sources of IL-10. As an example, we provide evidence that aberrant Fas-mediated deletion of IL-10-producing B cells subverts the immunoregulatory role of IL-10 in autoimmune diabetes and that modulation of the Fas pathway preserves the IL-10-producing B cells and completely protects NOD mice from developing the disease. PMID:25481648