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1.
Drug Res (Stuttg) ; 63(11): 572-8, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23780499

RESUMEN

Allergic rhinitis (AR) is characterized by inflammation of the nasal mucosa with hypersensitivity resulting from seasonal or perennial responses to specific environmental allergens and by symptoms like nasal rubbing, sneezing, rhinorrhea, lacrimation, nasal congestion and obstruction, and less frequently cough. KOB extracts, which is a polyherbal medicine consisting of 5 different herbs (Atractylodes macrocephala, Astragalus membranaceus, Saposhnikovia divaricata, Ostericum koreanum and Scutellaria baicalensis) had commonly been used for the treatment of various allergic diseases showed an anti-allergic effect by modulating mast cell-mediated allergic responses in allergic rhinitis, recently. On the other hand, pseudoephedrine is a sympathomimetic amine commonly used to relieve congestion in patients with allergic rhinitis and common colds. Considering the KOB's therapeutic mechanism, the combination with pseudoephedrine would be suitable for allergic rhinitis. This study is to obtain an effective extended release formulation using pseudoephedrine and KOB extracts to reduce side effects of drug due to repeated dosing and improve the compliance of patients for treatment of rhinitis and nasal decongestion. So, the fixed-dose combination tablet of pseudoephedrine and KOB extracts was prepared by direct compression and characterized by drug content, flowing characteristics and dissolution test. The drug content of baicalin of KOB extracts was within the range of 95-105% except for T1 formulation. The hardness and friability values of all formulations ranged from 9 to 13 kp and less than 1%, respectively. Taken together, T4 or T8 could be a stable fixed-dose combination tablet for extended release of pseudoephedrine and KOB extracts for nasal rhinitis.


Asunto(s)
Extractos Vegetales/administración & dosificación , Seudoefedrina/administración & dosificación , Preparaciones de Acción Retardada , Combinación de Medicamentos , Flavonoides/administración & dosificación , Flavonoides/química , Extractos Vegetales/química , Seudoefedrina/química , Rinitis Alérgica , Rinitis Alérgica Perenne/tratamiento farmacológico , Solubilidad , Comprimidos
2.
J Nanosci Nanotechnol ; 8(9): 4783-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19049108

RESUMEN

Vertically well-aligned ZnO nanowalls were successfully synthesized at 950-1050 degrees C. Ar gas was introduced into the furnace at a flow rate of 2000-2500 sccm. An Au thin film with a thickness of 3 nm was used as a catalyst. The ZnO nanowalls were successfully grown on the substrate and most of them had nearly the same thickness and were oriented perpendicular to the substrate. The morphology and chemical composition of the ZnO nanowalls were examined as a function of the growth conditions examined. It was found that the grown ZnO nanowalls have a single-crystalline hexagonal structure and preferred c-axis growth orientation based on the X-ray diffraction and high-resolution transmission electron microscope measurements. The room temperature photoluminescence showed a strong free-exciton emission band with negligible deep level emission, indicating the high optical property of our ZnO nanowall samples.


Asunto(s)
Óxido de Aluminio/química , Galio/química , Nanoestructuras/química , Nanotecnología/métodos , Óxido de Zinc/química , Cristalización , Diseño de Equipo , Luminiscencia , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie , Temperatura , Difracción de Rayos X
3.
Lett Appl Microbiol ; 43(3): 307-12, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16910937

RESUMEN

AIMS: To inhibit the growth of the bloom-forming cyanobacterium Microcystis aeruginosa using a rice straw extract. METHODS AND RESULTS: The cell numbers of the algal strain M. aeruginosa UTEX 2388 significantly decreased after treatment with different concentrations (0.01, 0.1, 1 and 10 mg l(-1)) of a rice straw extract for an 8-day cultivation period. Among seven tested allelochemicals from rice straw, salicylic acid at 0.1 mg l(1) exhibited the highest allelopathic activity (26%) on day 8. A synergistic effect on algal growth inhibition was found when adding two or three phenolic compounds from the rice straw. CONCLUSIONS: The growth of M. aeruginosa was inhibited by rice straw extract concentrations ranging from 0.01 to 10 mg l(1). This activity was due to the synergistic effects of various phenolic compounds in the rice straw. SIGNIFICANCE AND IMPACT OF THE STUDY: The identification of rice straw as an effective material for the growth inhibition of M. aeruginosa implies it may have the potential to be used as an environment-friendly biomaterial for controlling the algal bloom of M. aeruginosa in eutrophic water.


Asunto(s)
Antibacterianos/análisis , Antibacterianos/farmacología , Microcystis/efectos de los fármacos , Oryza/química , Feromonas/análisis , Feromonas/farmacología , Microcystis/crecimiento & desarrollo , Extractos Vegetales/farmacología , Tallos de la Planta/química
5.
J Pharm Pharmacol ; 53(9): 1287-94, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11578112

RESUMEN

Syringin was found to possess immunomodulatory activity by which it inhibited the in-vitro immunohaemolysis of antibody-coated sheep erythrocytes by guinea-pig serum through suppression of C3-convertase of the classical complement. In this study, we examined its in-vitro and in-vivo activity on tumour necrosis factor (TNF)-alpha and nitric oxide (NO) production, CD4+ T cell and CD8+ cytotoxic T cell (CTLL-2) proliferation, and croton oil-, arachidonic acid- and fluorescein-isothiocynate (FITC)-induced mouse ear oedema model. Syringin significantly inhibited both TNF-alpha production from lipopolysaccharide (LPS)-stimulated RAW264.7 cells and CD8+ T cell (CTLL-2) proliferation in a dose-dependent manner, whereas neither NO production nor CD4+ T cell proliferation were blocked even by high concentrations of syringin. In the invivo experiments, syringin also significantly suppressed FITC-induced ear oedema in mice but not the ear oedema induced by croton or arachidonic acid. These results suggest that syringin may be implicated as an immunomodulator having an anti-allergic effect rather than an anti-inflammatory effect. The anti-allergic effect of syringin seems to be due, in part, to inhibition of TNF-alpha production and cytotoxic T cell proliferation.


Asunto(s)
Adyuvantes Inmunológicos/farmacología , Glucósidos/inmunología , Glucósidos/farmacología , Fenilpropionatos/inmunología , Fenilpropionatos/farmacología , Linfocitos T Citotóxicos/efectos de los fármacos , Factor de Necrosis Tumoral alfa/efectos de los fármacos , Animales , Técnicas de Cultivo de Célula , División Celular/efectos de los fármacos , Cobayas , Sistema Inmunológico/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos ICR , Ovinos , Factor de Necrosis Tumoral alfa/biosíntesis
6.
Planta Med ; 67(4): 312-6, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11458445

RESUMEN

Coptis japonica Makino (Ranunculaceae) is known to possess several biological activities such as anti-inflammatory effects. In this study, five lignans, isolariciresinol (1), lariciresinol glycoside (2), pinoresinol (3), pinoresinol glycoside (4) and syringaresinol glycoside (5), isolated from the rhizomes of C. japonica were tested to evaluate their in vitro anti-inflammatory effects. Pinoresinol and isolariciresinol showed higher inhibitory effects on TNF-alpha production, whereas syringaresinol glycoside strongly suppressed lymphocyte proliferation. The results indicate that the lignans may differentially modulate inflammatory cell responses, suggesting that these compounds may participate in anti-inflammatory processes by C. japonica.


Asunto(s)
Antiinflamatorios no Esteroideos/aislamiento & purificación , Antiinflamatorios no Esteroideos/farmacología , Furanos/aislamiento & purificación , Furanos/farmacología , Glucósidos/aislamiento & purificación , Glucósidos/farmacología , Glicósidos/aislamiento & purificación , Glicósidos/farmacología , Lignanos/aislamiento & purificación , Lignanos/farmacología , Lignina/aislamiento & purificación , Lignina/farmacología , Medicina Tradicional , Naftoles/aislamiento & purificación , Naftoles/farmacología , Plantas Medicinales/química , Animales , Antiinflamatorios no Esteroideos/química , Linfocitos T CD4-Positivos/efectos de los fármacos , Células Cultivadas/efectos de los fármacos , Furanos/química , Glucósidos/química , Glicósidos/química , Interferón gamma/farmacología , Interleucina-2/metabolismo , Lignanos/química , Lignina/química , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos BALB C , Estructura Molecular , Naftoles/química , Óxido Nítrico/metabolismo , Bazo/citología , Bazo/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
7.
Planta Med ; 67(3): 213-8, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11345690

RESUMEN

Ginsenosides are the major principles of Panax ginseng C. A. Meyer (Araliaceae) used as a mild oriental folk medicine. In this report, we have examined the inhibitory potency of protopanaxadiol ginsenosides (PPDGs) such as Rb1, Rb2 and Rc, and their co-treatment effect with known tumor necrosis factor (TNF)-alpha antagonists on TNF-alpha production in either murine (RAW264.7) or human (U937) macrophages stimulated with lipopolysaccharide (LPS). Rb1, and Rb2 strongly suppressed TNF-alpha production in RAW264.7 cells with an IC50 of 56.5 and 27.5 microM, respectively, and in differentiated U937 cells with an IC50 of 51.3, and 26.8 microM, respectively. The inhibitory activity of Rb1 and Rb2 was significantly increased by pharmacological agents against protein kinase C, protein tyrosine kinase, and protein kinase A, and anti-rheumatoid arthritis drugs, such as chloroquine and steroid drugs. In contrast, only cyclic AMP phosphodiesterase (cAMP PDE) inhibitors among cAMP-elevating agents did not change the inhibitory potency of PPDGs. These data suggest that PPDGs may possess potential therapeutic efficacy against TNF-alpha mediated disease and the therapeutic potency of PPDGs may be enhanced when co-treated with various kinds of known TNF-alpha antagonists but not with cAMP PDE inhibitors.


Asunto(s)
Medicamentos Herbarios Chinos/farmacología , Péptidos y Proteínas de Señalización Intracelular , Saponinas/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , 3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Animales , Proteínas Portadoras/farmacología , Células Cultivadas , Cloroquina/farmacología , GMP Dibutiril Cíclico/farmacología , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Ginsenósidos , Humanos , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Panax , Plantas Medicinales , Saponinas/antagonistas & inhibidores , Esteroides/farmacología , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/biosíntesis
8.
Acta Otolaryngol ; 121(2): 178-81, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11349773

RESUMEN

Bone destruction is known to be an important cause of complications in chronic cholesteatomatous otitis media. A strategy that blocks localized bone resorption may prevent the progression of the disease. The bisphosphonate drug pamidronate is known to inhibit bone resorption and has been used in the treatment of Paget's disease and osteoporosis. The aim of this study was to investigate the effect of pamidronate on the inhibition of bone resorption in cholesteatoma using a neonatal rat calvarial culture system. Radioactive calcium was subcutaneously injected into pregnant rats. Neonatal calvariae were harvested after i.p. injection of pamidronate disodium to neonatal rats and culture supernatants of cholesteatoma keratinocytes were then added to the calvarial culture media. Radioactive calcium release was measured using a beta-ray scintillation counter. The percentage of calcium release was significantly higher in cholesteatoma culture supernatant than in Dulbecco's modification of Eagle's medium. The percentage calcium release in cholesteatoma culture supernatant was significantly lower with the high dose of pamidronate than with the low dose. These results suggest that pamidronate can inhibit the bone resorption caused by cholesteatoma. This study suggests a possible application for pamidronate in the prevention of cholesteatomatous bone destruction.


Asunto(s)
Antiinflamatorios/farmacología , Resorción Ósea/fisiopatología , Colesteatoma del Oído Medio/fisiopatología , Difosfonatos/farmacología , Animales , Animales Recién Nacidos , Calcio/metabolismo , Enfermedad Crónica , Técnicas de Cultivo , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Otitis Media/fisiopatología , Pamidronato , Embarazo , Ratas
9.
J Nat Prod ; 63(9): 1205-9, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11000020

RESUMEN

Five dihydrobenzofuran neolignans, woorenosides I (1), II (2), III (3), IV (4), and V (5), isolated from Coptis japonica (Ranunculaceae), suppressed tumor necrosis factor (TNF)-alpha and nitric oxide (NuOmicron) production, as well as lymphocyte proliferation triggered by inflammatory signals such as various mitogens, in a dose-dependent manner. The results indicate that the woorenosides strongly inhibit the mitogenic response by activated macrophage and lymphocytes and suggest that these compounds may participate in regulating inflammatory processes.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Lignanos/farmacología , Plantas Medicinales/química , Animales , Antiinflamatorios no Esteroideos/aislamiento & purificación , Línea Celular , Interleucina-2/farmacología , Lignanos/aislamiento & purificación , Linfocitos/efectos de los fármacos , Linfocitos/metabolismo , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos BALB C , Óxido Nítrico/antagonistas & inhibidores , Óxido Nítrico/biosíntesis , Bazo/citología , Bazo/efectos de los fármacos , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
10.
J Ethnopharmacol ; 70(2): 127-33, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10771202

RESUMEN

Certain flavonoids were reported to show an immunoregulatory activity against lymphocyte proliferation and cytokine production. In the course of a search for tumor necrosis factor (TNF)-alpha inhibitory compounds from natural plants, we also isolated a prenylfavanone type of flavonoid, amoradicin, from the extract of Amorpha fruticosa by activity-guided fractionation. This compound significantly inhibited TNF-alpha production in lipopolysaccharide (LPS)-stimulated RAW264.7 cells with an IC(50) value of 28.5 microM. The activity was comparable or higher than those of standard flavonoid compounds, genistein and silybin with IC(50) of 24.9 and 140.3 microM, respectively.


Asunto(s)
Flavonoides/farmacología , Lipopolisacáridos/farmacología , Plantas Medicinales , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Línea Celular , Genisteína/farmacología , Corea (Geográfico) , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Ratones , Plantas Medicinales/química , Silimarina/farmacología , Relación Estructura-Actividad , Factor de Necrosis Tumoral alfa/biosíntesis
11.
Clin Rheumatol ; 18(3): 253-6, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-11206354

RESUMEN

Patients with systemic lupus erythematosus (SLE) are reported to have an increased risk of malignancy, especially lymphoproliferative disorders. We decribe the occurrence of ileocaecal intussusception secondary to Burkitt's lymphoma in a patient with SLE. A 23-year-old woman, who had been diagnosed with SLE 2 years ago, developed intermittent abdominal pain with a palpable mass. Computed tomography and a double-contrast barium enema showed a lobulated mass with intussusception at the ileocaecal junction. Right hemicolectomy and splenectomy was performed after histopathological examinations on colonoscopic biopsy revealed Burkitt's lymphoma. Fourteen months after chemotherapy, there is no evidence of recurrence of the Burkitt's lymphoma. When a patient with SLE has abdominal complaints, besides serositis, lupus enteritis such as peptic ulcer disease, mesenteric vasculitis with or without complications and pancreatitis, we have to consider intussusception secondary to gastrointestinal lymphoma as one of the differential diagnoses. Therefore, we should thoroughly investigate patients with SLE presenting with abdominal pain and not simply consider it afeature of lupus enteritis until other causes have been ruled out.


Asunto(s)
Linfoma de Burkitt/diagnóstico , Enfermedades del Íleon/diagnóstico , Válvula Ileocecal/patología , Intususcepción/diagnóstico , Lupus Eritematoso Sistémico/patología , Adulto , Linfoma de Burkitt/complicaciones , Diagnóstico Diferencial , Femenino , Humanos , Enfermedades del Íleon/etiología , Intususcepción/etiología , Lupus Eritematoso Sistémico/complicaciones , Tomografía Computarizada por Rayos X
12.
Planta Med ; 64(7): 594-7, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9810262

RESUMEN

Total methanol extract of Saussurea lappa radix (Compositae) showed potent inhibitory effect on the production of tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, in murine macrophage-like cell (RAW264.7 cells) in our previous screening studies on 120 Korean medicinal plants. The activity-guided purification of the plant resulted in the isolation of three components. The chemical structures of the components isolated were established by spectroscopic analyses as sesquiterpene lactones [cynaropicrin (1), reynosin (2), and santamarine (3)]. These three compounds inhibited TNF-alpha production in a dose-dependent manner. The molar concentrations of cynaropicrin, reynosin, and santamarine producing 50% inhibition (IC50) of TNF-alpha production were 2.86 micrograms/ml (8.24 microM), 21.7 micrograms/ml (87.4 microM), and 26.2 micrograms/ml (105 microM), respectively. However, treatment with sulphydryl (SH) compounds such as L-cysteine, dithiothreitol, and 2-mercaptoethanol abrogated the inhibitory effect of cynaropicrin on TNF-alpha production. Therefore, we conclude that the principal inhibitory component of Saussurea lappa is cynaropicrin and its inhibitory effect is mediated through conjugation with SH-groups of target proteins.


Asunto(s)
Lactonas/farmacología , Plantas Medicinales/química , Sesquiterpenos/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Animales , Línea Celular , Lactonas/química , Lactonas/aislamiento & purificación , Ratones , Estructura Molecular , Sesquiterpenos/química , Sesquiterpenos/aislamiento & purificación , Factor de Necrosis Tumoral alfa/biosíntesis
13.
Arch Pharm Res ; 21(1): 12-6, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9875508

RESUMEN

The inhibitory effect of 10 lignan constituents isolated from the rhizomes of Coptis japonica var. dissecta on tumor necrosis factor (TNF)-alpha production in lipopolysaccharide (LPS)-stimulated macrophage cell line (RAW264.7 cells) has been studied. Among them, pinoresinol, woorenoside-V and lariciresinol glycoside showed significant inhibitory activities in the range from 37% to 55% at the concentration of 25 micrograms/ml. The results are first report that the lignans isolated from Coptis japonica inhibit TNF-alpha production, and suggest that the lignan components may partly participate in antiinflammatory and antiallergic effect of Coptis japonica through the inhibition of TNF-alpha production.


Asunto(s)
Lignanos/farmacología , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Raíces de Plantas/química , Plantas Medicinales/química , Factor de Necrosis Tumoral alfa/biosíntesis , 3',5'-AMP Cíclico Fosfodiesterasas/antagonistas & inhibidores , Antiinflamatorios no Esteroideos/farmacología , Inhibidores Enzimáticos/farmacología , Humanos , Corea (Geográfico) , Lignanos/química , Macrófagos/efectos de los fármacos , Medicina Tradicional , Relación Estructura-Actividad
14.
Arch Pharm Res ; 21(1): 67-9, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9875517

RESUMEN

Three TNF alpha-inhibitory lignans were isolated from the flower buds of Magnolia fargesii through bioassay-guided isolation. They were identified as eudesmin, magnolin and lirioresinol-B dimethylether on the basis of their spectroscopic data. All three lignans showed inhibitory effects on TNF-alpha production in LPS-stimulated murine macrophage cell line, RAW264.7 and eudesmin showed the strongest activity (IC50 = 51 microM).


Asunto(s)
Plantas Medicinales/química , Factor de Necrosis Tumoral alfa/biosíntesis , Línea Celular , Cromatografía Líquida de Alta Presión , Cromatografía en Capa Delgada , Humanos , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
16.
J Biol Chem ; 272(51): 32679-85, 1997 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-9405486

RESUMEN

Deoxyhypusine synthase catalyzes the first step in the post-translational synthesis of hypusine [Nepsilon-(4-amino-2-hydroxybutyl)lysine] in eukaryotic translation initiation factor 5A. We recently reported biochemical evidence for a covalent enzyme-substrate intermediate involving a specific lysine residue (Lys329) in human deoxyhypusine synthase (Wolff, E. C., Folk, J. E., and Park, M. H. (1997) J. Biol. Chem. 272, 15865-15871). In an effort to evaluate the role of this enzyme-substrate intermediate in catalysis, we carried out site-directed mutagenesis (Lys to Arg and/or Ala) of the conserved lysine residues in human deoxyhypusine synthase. A drastic reduction in enzyme intermediate formation and enzymatic activities was observed with mutant proteins with substitution at Lys287 but not with those with mutations at residues 141, 156, 205, 212, 226, 251, or 338. Lys to Ala or Lys to Arg substitution at Lys329 totally abolished covalent enzyme-substrate intermediate formation and deoxyhypusine synthesis activity, indicating that Lys329 is the unique site for the enzyme intermediate and that it is absolutely required for deoxyhypusine synthesis in the eukaryotic translation initiation factor 5A precursor. The K329A mutant showed spermidine cleavage activity ( approximately 6% of the wild type enzyme) suggesting that in contrast to deoxyhypusine synthesis, spermidine cleavage can occur without enzyme intermediate formation.


Asunto(s)
Lisina/análogos & derivados , Lisina/metabolismo , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Biopolímeros , Humanos , Lisina/biosíntesis , Mutagénesis Sitio-Dirigida , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/química , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Espermidina/metabolismo , Especificidad por Sustrato
17.
J Biol Chem ; 270(31): 18408-12, 1995 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-7629166

RESUMEN

Deoxyhypusine synthase catalyzes the formation of deoxyhypusine, the first step in hypusine biosynthesis. Amino acid sequences of five tryptic peptides from rat deoxyhypusine synthase were found to match partially the deduced amino acid sequence of the open reading frame of gene YHR068w of Saccharomyces cerevisiae chromosome VIII (AC:U00061). In order to determine whether the product of this gene corresponds to yeast deoxyhypusine synthase,a 1.17-kilobase pair cDNA with an identical nucleotide sequence to that of the YHR068w coding region was obtained from S. cerevisiae cDNA by polymerase chain reaction and was expressed in Escherichia coli B strain BL21 (DE3). The recombinant protein was found mostly in the E. coli cytosol fraction and comprised approximately 20% of the total soluble protein. The purified form of the expressed protein effectively catalyzed the formation of deoxyhypusine in yeast eIF-5A precursors as well as in human precursor and in those from Chinese hamster ovary cells. The molecular mass of the enzyme was estimated to be 172,000 +/- 4,300 Da by equilibrium centrifugation. The mass of its polypeptide subunit was determined to be approximately 43,000 Da, in close agreement with that calculated for the coding region of the YHRO68w gene. These findings show that this gene is a coding sequence for yeast deoxyhypusine synthase and that the product of this gene exists in a tetrameric form.


Asunto(s)
Cromosomas Fúngicos/genética , Genes Fúngicos/genética , Lisina/análogos & derivados , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/genética , Proteínas de Unión al ARN , Saccharomyces cerevisiae/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , ADN Complementario/genética , Escherichia coli/genética , Proteínas Fúngicas/biosíntesis , Proteínas Fúngicas/genética , Humanos , Lisina/biosíntesis , Masculino , Datos de Secuencia Molecular , Peso Molecular , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/biosíntesis , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/aislamiento & purificación , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Factores de Iniciación de Péptidos/metabolismo , Reacción en Cadena de la Polimerasa , Ratas , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/enzimología , Homología de Secuencia de Aminoácido , Testículo/metabolismo , Factor 5A Eucariótico de Iniciación de Traducción
18.
J Med Chem ; 38(16): 3053-61, 1995 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-7636868

RESUMEN

Deoxyhypusine synthase catalyzes the initial step in the posttranslational formation of the amino acid hypusine [N epsilon-(4-amino-2-hydroxybutyl)lysine] in eukaryotic initiation factor 5A (eIF-5A). eIF-5A and its hypusine modification are believed to be essential for cell growth. A number of compounds related to diamines and triamines were synthesized and tested as inhibitors of this enzyme. The findings indicate that the long chain triamines 2a and 2b and their guanyl derivatives 3a, 3b, 4a, and 4b exert inhibition by binding to enzyme through only a portion of their structures at any one time. The inhibition exhibited by N-ethyl-1,7-diaminoheptane 20 and its guanyl derivative 21 supports this notion and is evidence for participation of the secondary amino group in binding to enzyme. There is preliminary evidence that amidino and isothiuronium groups may also serve as basic centers for binding to enzyme. Few of the compounds tested here were comparable in inhibitory potency to 1-guanidino-7-aminoheptane (GC7) the most effective known inhibitor of deoxhypusine synthase, and none proved nearly as efficient as GC7 in inhibiting the enzyme in Chinese hamster ovary cells. Hence, unlike the antiproliferative effect of GC7, for which there is evidence of cause by interference with deoxhypusine synthase catalysis (Park, M. H.; Wolff, E. C.; Lee, Y. B.; Folk, J. E. J. Biol. Chem. 269, 1994, 27827-27832), the effective growth arrest exerted by several of the newly synthesized compounds cannot be attributed to inhibition of hypusine synthesis.


Asunto(s)
Diaminas/farmacología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/antagonistas & inhibidores , Poliaminas/farmacología , Proteínas de Unión al ARN , Animales , Unión Competitiva , Células CHO , División Celular/efectos de los fármacos , Cricetinae , Cricetulus , Diaminas/química , Humanos , Lisina/análogos & derivados , Lisina/metabolismo , Masculino , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/metabolismo , Factores de Iniciación de Péptidos/metabolismo , Poliaminas/química , Ratas , Espermidina/metabolismo , Relación Estructura-Actividad , Testículo/enzimología , Factor 5A Eucariótico de Iniciación de Traducción
19.
J Biol Chem ; 269(45): 27827-32, 1994 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-7961711

RESUMEN

Certain guanyl diamines are effective inhibitors of deoxyhypusine synthase (Jakus, J., Wolff, E. C., Park, M. H., and Folk, J. E. (1993) J. Biol. Chem. 268, 13151-13159), the first enzyme involved in the biosynthesis of the unusual amino acid hypusine (N epsilon-(4-amino-2-hydroxybutyl)lysine). Evidence that hypusine is implicated in cell growth prompted this study of the cellular effects of these inhibitors. In Chinese hamster ovary (CHO) cells, inhibition of hypusine biosynthesis followed by progressive arrest in cellular proliferation was observed with both N-mono- and N,N'-bisguanyl derivatives of 1,6-diaminohexane, 1,7-diaminoheptane, and 1,8-diaminooctane. Cells treated with these compounds showed no significant change in polyamine distribution, suggesting that the observed growth inhibition is not mediated through an interference with polyamine metabolism. N1-guanyl-1,7-diaminoheptane, the most potent inhibitor of deoxyhypusine synthase both in vitro and in cells, exhibited the highest antiproliferative activity toward CHO cells. No early cytotoxic effects were observed with this inhibitor, and its antiproliferative activity appeared to be reversible. Transport studies showed that N1-guanyl-1,7-diaminoheptane is actively taken up by the polyamine transport system. Mutant CHO cells defective in polyamine transport were found to be resistant to growth inhibition by this compound. The findings suggest that the antiproliferative effect of N1-guanyl-1,7-diaminoheptane is exerted intracellularly through inhibition of hypusine synthesis.


Asunto(s)
División Celular/efectos de los fármacos , Diaminas/farmacología , Guanina/análogos & derivados , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/antagonistas & inhibidores , Poliaminas/metabolismo , Animales , Células CHO , Supervivencia Celular/efectos de los fármacos , Cricetinae , Diaminas/síntesis química , Relación Dosis-Respuesta a Droga , Guanina/síntesis química , Guanina/farmacología , Indicadores y Reactivos , Cinética , Lisina/análogos & derivados , Lisina/metabolismo , Biosíntesis de Proteínas , Putrescina/metabolismo , Espermidina/metabolismo , Espermina/metabolismo , Relación Estructura-Actividad
20.
Gene ; 137(2): 303-7, 1993 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-7916728

RESUMEN

Chick embryo contains 18- and 20-kDa isoforms of eukaryotic translation initiation factor 5A (eIF-5A). cDNA clones corresponding to the 20-kDa eIF-5A were isolated and sequenced. A full-length cDNA clone encodes a 153-amino-acid (aa) protein. The deduced aa sequence exactly matches with the partial aa sequence determined for this protein and shows high identity to that of human or rabbit eIF-5A. The results of Southern and Northern hybridization provide evidence for multiple transcripts for chick embryo eIF-5A or an eIF-5A-like protein that presumably derive from more than one gene.


Asunto(s)
Lisina/análogos & derivados , Factores de Iniciación de Péptidos/genética , Proteínas de Unión al ARN , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Northern Blotting , Southern Blotting , Embrión de Pollo , Clonación Molecular , ADN Complementario , Humanos , Lisina/química , Lisina/genética , Datos de Secuencia Molecular , Factores de Iniciación de Péptidos/química , Conejos , Factor 5A Eucariótico de Iniciación de Traducción
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