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1.
Biomed Res Int ; 2022: 1382878, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35342748

RESUMO

Background: Inflammation is a frequent phenomenon in the pathogenesis of hepatic disorders leading to fibrosis and cirrhosis. Phytopharmaceuticals developed from traditional medicine can provide effective therapeutic alternatives to conventional medications. Datura stramonium (DS) has reported traditional uses in inflammatory diseases. In this study, we have tried to validate its potential as a source of anti-inflammatory agents. Methods: Powdered leaf part of DS was extracted using ethyl acetate (EA) to provide the extract (DSL-EA). Lymphocyte and macrophage viability and acute toxicity assays established the safety profile, while nitric oxide (NO) scavenging assay estimated the in vitro anti-inflammatory potential. Noninvasive anti-inflammatory, antidepressant, and antinociceptive activities were monitored using BALB/c mice using low and high doses (150 and 250 mg/kg). Major inflammatory studies were performed on Sprague-Dawley male rats using CCl4-induced liver injury model. Disease induction was initiated by intraperitoneal injections of CCl4 (1 mL/kg of 30% CCl4 in olive oil). The rats were divided into six groups. The anti-inflammatory potential of DSL-EA in low and high doses (150 and 300 mg/kg, respectively) was assessed through hematological, biochemical, liver antioxidant defense, oxidative stress markers, and histological studies as well as the expression of Nrf2 and iNOS. Results: DSL-EA exhibited prominent in vitro NO scavenging (IC50: 7.625 ± 0.51 µg/mL) and in vivo anti-inflammatory activity in paw and anal edema models. In CCl4 model, hematological investigations revealed vasotonic effects. Liver functionality was significantly (P < 0.001 - 0.05) improved in DSL-EA-treated rats. The activity level of endogenous antioxidant enzymes in liver tissues was improved in a manner identical to silymarin. The extract reduced the percent concentration of oxidative stress markers in liver tissues. Furthermore, DSL-EA displayed restorative effects on histological parameters (H and E and Masson's trichrome staining). Immunohistochemistry studies showed marked decline in Nrf2 expression, while overexpression of iNOS was also observed in disease control rats. The damage was distinctly reversed by the extract.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Datura stramonium , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Biomarcadores/metabolismo , Tetracloreto de Carbono/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/patologia , Datura stramonium/metabolismo , Fígado/patologia , Masculino , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Extratos Vegetais , Ratos , Ratos Sprague-Dawley
2.
Sci Rep ; 11(1): 882, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441607

RESUMO

Tropane alkaloids and terpenoids are widely used in the medicine and pharmaceutic industry and evolved as chemical defenses against herbivores and pathogens in the annual herb Datura stramonium (Solanaceae). Here, we present the first draft genomes of two plants from contrasting environments of D. stramonium. Using these de novo assemblies, along with other previously published genomes from 11 Solanaceae species, we carried out comparative genomic analyses to provide insights on the genome evolution of D. stramonium within the Solanaceae family, and to elucidate adaptive genomic signatures to biotic and abiotic stresses in this plant. We also studied, in detail, the evolution of four genes of D. stramonium-Putrescine N-methyltransferase, Tropinone reductase I, Tropinone reductase II and Hyoscyamine-6S-dioxygenase-involved in the tropane alkaloid biosynthesis. Our analyses revealed that the genomes of D. stramonium show signatures of expansion, physicochemical divergence and/or positive selection on proteins related to the production of tropane alkaloids, terpenoids, and glycoalkaloids as well as on R defensive genes and other important proteins related with biotic and abiotic pressures such as defense against natural enemies and drought.


Assuntos
Datura stramonium/genética , Datura stramonium/metabolismo , Defesa das Plantas contra Herbivoria/genética , Oxirredutases do Álcool/metabolismo , Alcaloides/metabolismo , Evolução Biológica , Meio Ambiente , Evolução Molecular , Interação Gene-Ambiente , Genômica/métodos , Solanaceae/genética , Solanaceae/metabolismo , Tropanos/metabolismo , Sequenciamento Completo do Genoma
3.
Sci Rep ; 10(1): 9749, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546786

RESUMO

Globalization facilitated the spread of invasive alien species (IAS), undermining the stability of the world's ecosystems. We investigated the metabolomic profiles of three IAS species: Chromolaena odorata (Asteraceae) Datura stramonium (Solanaceae), and Xanthium strumarium (Asteraceae), comparing metabolites of individual plants in their native habitats (USA), to their invasive counterparts growing in and around Kruger National Park (South Africa, ZA). Metabolomic samples were collected using RApid Metabolome Extraction and Storage (RAMES) technology, which immobilizes phytochemicals on glass fiber disks, reducing compound degradation, allowing long-term, storage and simplifying biochemical analysis. Metabolomic differences were analyzed using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) of samples eluted from RAMES disks. Partial Least Squares-Discriminant Analysis (PLS-DA) of metabolomes of individual plants allowed statistical separation of species, native and invasive populations of each species, and some populations on the same continent. Invasive populations of all species were more phytochemically diverse than their native counterparts, and their metabolomic profiles were statistically distinguishable from their native relatives. These data may elucidate the mechanisms of successful invasion and rapid adaptive evolution of IAS. Moreover, RAMES technology combined with PLS-DA statistical analysis may allow taxonomic identification of species and, possibly, populations within each species.


Assuntos
Chromolaena/metabolismo , Datura stramonium/metabolismo , Espécies Introduzidas/tendências , Xanthium/metabolismo , Cromatografia Líquida/métodos , Chromolaena/genética , Datura stramonium/genética , Análise Discriminante , Ecossistema , Metaboloma/genética , Metabolômica/métodos , África do Sul , Especificidade da Espécie , Espectrometria de Massas em Tandem/métodos , Xanthium/genética
4.
Zhongguo Zhong Yao Za Zhi ; 38(11): 1712-8, 2013 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-24010283

RESUMO

OBJECTIVE: To study the effects of methyl jasmonate (MJ) on the accumulation and release of main secondary metabolites i. e. scopolamine and hyoscyamine in liquid cultures of Datura stramonium hairy roots. METHOD: After 18 days liquid culture of D. stramonium hairy roots induced by agrobacterium rhizogenes C58C1, the chemical elicitor methyl jasmonate was added into 1/2 MS liquid cultures and scopolamine and hyoscyamine on the day 0, 3, 6, 9 and 12, after dealing with MJ, was determined by HPLC. RESULT: After dealing with MJ on the day 3, 6, 9 and 12,the concentration of scopolamine reached to 0.419, 0.439, 0.431, 0.374 mg x g(-1), respectively, the increase of scopolamine were 1.36, 1.42, 1.17 and 1.12 fold higher than that of the control, respectively. And hyoscyamine reached 1.493, 0.817, 0.723 and 0.698 mg x g(-1), respectively, the increase of hyoscyamine were 2.28, 1.11, 0.63 and 0.70 fold higher than that of the control, respectively. CONCLUSION: MJ could stimulate the accumulation of scopolamine and hyoscyamine (3,6 d) in D. stramonium hairy root and have released them into the culture medium.


Assuntos
Acetatos/farmacologia , Alcaloides/metabolismo , Ciclopentanos/farmacologia , Datura stramonium/efeitos dos fármacos , Datura stramonium/metabolismo , Oxilipinas/farmacologia , Tropanos/metabolismo , Alcaloides/análise , Técnicas de Cultura de Células , Datura stramonium/química , Datura stramonium/crescimento & desenvolvimento , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Tropanos/análise
5.
Appl Biochem Biotechnol ; 157(2): 210-25, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-18509605

RESUMO

Hyoscyamine biosynthesis in Datura stramonium hairy roots with different ploidy levels was investigated. For the first time, we report that hairy roots undergo endoreduplication and therefore consist mainly of cells with doupled sets of chromosomes of primary plant tissues, used for Agrobacterium transformation. The alkaloid profiles of hairy roots obtained from diploid and tetraploid plants were similar in terms of the major compounds, but they differed significantly with respect to the minor compounds (here defined as those that accounted for <1% of the total ion current of the alkaloid mixture in gas chromatography-mass spectrometric analyses). Significant differences in the effects of the main nutrients on the growth of the hairy roots obtained from diploid and tetraploid plants and their hyoscyamine contents were observed. The maximal yield of hyoscyamine (177 mg/L) was obtained when hairy roots from tetraploid plants were cultivated in Murashige-Skoog nutrient medium supplemented with 6% sucrose. Time courses of utilization of the main nutrients in the medium during cultivation of D. stramonium hairy root cultures are also presented.


Assuntos
Atropina/biossíntese , Datura stramonium/metabolismo , Raízes de Plantas/metabolismo , Ploidias , Alcaloides/análise , Biomassa , DNA de Plantas/análise , Datura stramonium/citologia , Datura stramonium/efeitos dos fármacos , Datura stramonium/crescimento & desenvolvimento , Diploide , Citometria de Fluxo , Nitratos/farmacologia , Fosfatos/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Poliploidia , Compostos de Amônio Quaternário/farmacologia , Sacarose/farmacologia , Fatores de Tempo , Água
6.
Yao Xue Xue Bao ; 41(10): 963-6, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17184114

RESUMO

AIM: To investigate the production of p-hydroxymethylphenol-beta-D-glucoside (gastrodin) through biotransformation by plant cell suspension cultures. METHODS: Using cell suspension cultures of Datura stramonium to convert the exogenous p-hydroxybenzaldehyde into gastrodin was conducted and the converted compounds were separated with a combination of multi-chromatography. Their chemical structures were determined on the basis of spectral analysis and chemical evidence. RESULTS: The conversion procedure of p-hydroxybenzaldehyde into gastrodin by Datura stramonium cell suspension cultures was established. The synthesized gastrodin (II) was isolated from the fermental liquor and identified by spectral analysis. At the same time, the p-hydroxybenzyl alcohol (I) converted through biotransformation of p-hydroxybenzaldehyde by cell suspension cultures of Datura stramonium was also isolated and identified. Two compounds were also isolated from the cell cultures and they were identified as beta-D-furanoallulose (III) and n-butyloxystyryl-beta-D-pyranoallulose (IV). CONCLUSION: Datura stramonium grown in suspension cultures can convert exogenous p-hydroxybenzaldehyde into the corresponding gastrodin.


Assuntos
Benzaldeídos/metabolismo , Datura stramonium/metabolismo , Glucosídeos/biossíntese , Álcoois Benzílicos/isolamento & purificação , Álcoois Benzílicos/metabolismo , Biotransformação , Técnicas de Cultura de Células/métodos , Células Cultivadas , Datura stramonium/citologia , Glucosídeos/isolamento & purificação , Caules de Planta/citologia , Plantas Medicinais/citologia , Plantas Medicinais/metabolismo
7.
Pest Manag Sci ; 57(1): 46-56, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11455632

RESUMO

The metabolism of the herbicide glufosinate-ammonium was investigated in heterotrophic cell suspension and callus cultures of transgenic (bar-gene) and non-transgenic sugarbeet (Beta vulgaris). Similar studies were performed with suspensions of carrot (Daucus carota), purple foxglove (Digitalis purpurea) and thorn apple (Datura stramonium). 14C-labelled chemicals were the (racemic) glufosinate, L-glufosinate, and D-glufosinate, as well as the metabolites N-acetyl L-glufosinate and 3-(hydroxymethylphosphinyl)propionic acid (MPP). Cellular absorption was generally low, but depended noticeably on plant species, substance and enantiomer. Portions of non-extractable residues ranged from 0.1% to 1.2% of applied 14C. Amounts of soluble metabolites resulting from glufosinate or L-glufosinate were between 0.0% and 26.7% of absorbed 14C in non-transgenic cultures and 28.2% and 59.9% in transgenic sugarbeet. D-Glufosinate, MPP and N-acetyl L-glufosinate proved to be stable. The main metabolite in transgenic sugarbeet was N-acetyl L-glufosinate, besides traces of MPP and 4-(hydroxymethylphosphinyl)butanoic acid (MPB). In non-transgenic sugarbeet, glufosinate was transformed to a limited extent to MPP and trace amounts of MPB. In carrot, D stramonium and D purpurea, MPP was also the main product; MPB was identified as a further trace metabolite in D stramonium and D purpurea.


Assuntos
Aminobutiratos/metabolismo , Herbicidas/metabolismo , Magnoliopsida/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Aminobutiratos/química , Células Cultivadas , Chenopodiaceae/metabolismo , Cromatografia Líquida de Alta Pressão , Datura stramonium/metabolismo , Daucus carota/metabolismo , Digitalis/metabolismo , Herbicidas/química , Plantas Medicinais , Plantas Tóxicas
8.
J Exp Bot ; 51(347): 1127-33, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10948240

RESUMO

Seed germination is often induced by a pulse of red light perceived by phytochrome and cancelled by a subsequent pulse of far-red light. When the pulse of red light is followed by several hours of darkness, a pulse of far-red light is no longer effective and prolonged far-red is necessary to block germination. The aim was to investigate whether the red light pulse and prolonged far-red light act on the same or different processes during germination of Datura ferox seeds. Forty-five hours after the inductive red light pulse, germination could not be blocked by one pulse or six hourly pulses of far-red light, but was significantly reduced by 6 h of continuous far-red light. The pulse of red light increased embryo growth potential and the activities of beta-mannanase and beta-mannosidase extracted from the micropylar region of the endosperm. Continuous far-red light had no effect on embryo growth potential or beta-mannosidase activity, but severely reduced the activity of beta-mannanase. The effect of far-red light had the features of a high-irradiance response of phytochrome. Both germination and beta-mannanase activity were restored by a pulse of red light given after the end of the continuous far-red treatment. It is concluded that the low-fluence response and the high-irradiance response modes of phytochrome have antagonistic effects on seed germination and that the control of beta-mannanase activity is one process where this antagonism is established.


Assuntos
Datura stramonium/efeitos da radiação , Germinação/efeitos da radiação , Luz , Manosidases/metabolismo , Fitocromo/fisiologia , Plantas Medicinais , Plantas Tóxicas , Sementes/efeitos da radiação , Datura stramonium/crescimento & desenvolvimento , Datura stramonium/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , beta-Manosidase
9.
Phytochemistry ; 53(7): 777-84, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10783983

RESUMO

Isotopic labelling experiments have been carried out in Datura stramonium root cultures with the following isotopically labelled precursors; [2H3]- [2-13C, 2H3]-, [1-13C, 18O2]-acetates, 2H2O, [2H3-methyl]-methionine, [2-13C]-phenyllactate, [3-2H]-tropine and [2'-13C, 3-2H]-littorine. The study explored the incorporation of isotope into the tropane ring system of littorine 1 and hyoscyamine 2 and revealed that deuterium from acetate is incorporated only into C-6 and C-7, and not into C-2 and C-4 as previously reported. Oxygen-18 was not retained at a detectable level into the C(3)-O bond from [1-13C, 18O2]-acetate. The intramolecular nature of the rearrangement of littorine 1 to hyoscyamine 2 is revealed again by a labelling study using [2'-13C, 3-2H]-littorine, [2-13C]-phenyllactate and [3-2H]-tropine.


Assuntos
Alcaloides/biossíntese , Datura stramonium/metabolismo , Plantas Medicinais , Plantas Tóxicas , Tropanos/química , Alcaloides/química , Espectroscopia de Ressonância Magnética , Estrutura Molecular
10.
C R Acad Sci III ; 322(9): 743-8, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10547716

RESUMO

The metabolism of labelled pyruvate followed by 13C NMR and the measure of glutamine synthetase (GS) showed, according to previous results, a high activity of this enzyme in suspension cells of Nicotiana plumbaginifolia. This activity could derive glutamate from the alkaloid synthesizing pathways. However, a recent work showed that the rate of the GS gene transcription was inversely proportional to the Gln/Glu ratio. The measures of Gln and Glu concentrations in Nicotiana plumbaginifolia cells revealed that high GS activity correlates with the weak value of Gln/Glu ratio. Therefore, the hypothesis of GS dysfunctioning for the non-biosynthesis of alkaloids in N. plumbaginifolia suspension cells can be discarded. This conclusion is strengthened by the results obtained when using a GS inhibitor.


Assuntos
Alcaloides/biossíntese , Datura stramonium/metabolismo , Glutamato-Amônia Ligase/metabolismo , Ácido Glutâmico/biossíntese , Glutamina/biossíntese , Nicotiana/metabolismo , Proteínas de Plantas/metabolismo , Plantas Medicinais , Plantas Tóxicas , Ácido gama-Aminobutírico/biossíntese , Células Cultivadas , Datura stramonium/genética , Indução Enzimática , Inibidores Enzimáticos/farmacologia , Regulação da Expressão Gênica de Plantas , Glutamato-Amônia Ligase/antagonistas & inibidores , Glutamato-Amônia Ligase/genética , Espectroscopia de Ressonância Magnética , Metionina Sulfoximina/farmacologia , Proteínas de Plantas/antagonistas & inibidores , Proteínas de Plantas/genética , Especificidade da Espécie , Suspensões , Nicotiana/genética
11.
Planta Med ; 65(2): 144-8, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10193206

RESUMO

Hairy root lines of Datura metel were established following infection of aseptic stem segments with Agrobacterium rhizogenes strain A4 and cultured in hormone-free B5 solid medium. The growth and production of hyoscyamine and scopolamine (mg/g dry wt.) of these root cultures was encouraged by using B5 liquid medium with half-strength salts. In these culture conditions, the capacity of the highest productive root line 25 to excrete scopolamine into the culture medium rose from 8.7% to 70% when the permeabilizing agent Tween 20 was added for 24 h to the medium, after 2 and 4 weeks of culture. Using an airlift bioreactor (41) with modifications in order to increase root anchorage, the Tween 20 treatment encouraged both growth and alkaloid productivity of cultured root line 25. After 4 weeks their biomass yield was 2.3 mg/l/day and 0.84 mg/l/day of scopolamine was produced (70% extracellular). The scopolamine released into the culture medium was separated with an Amberlite XAD-2 column located in the media exit.


Assuntos
Alcaloides/biossíntese , Datura stramonium/metabolismo , Plantas Medicinais , Plantas Tóxicas , Alcaloides/química , Reatores Biológicos , Raízes de Plantas/metabolismo , Tropanos/química
12.
Trends Biotechnol ; 17(1): 21-4, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10098274

RESUMO

The strictly aerobic bacterium Vitreoscilla expresses a hemoglobin-like protein, VHb, when subjected to oxygen stress. When expressed in plants, this has several intriguing physiological effects, such as improving the overall growth rate, speeding germination and flowering, and increasing the productivity of certain oxygen-requiring metabolic pathways. Although the mechanisms behind the effects of VHb in heterologous hosts are not yet fully characterized, it has been suggested that VHb facilitates oxygen transport and/or storage. This hypothesis is supported by the kinetic properties of VHb, which allow very rapid dissociation of oxygen from the protein.


Assuntos
Bactérias Aeróbias/metabolismo , Hemoglobinas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Datura stramonium/metabolismo , Hemoglobinas/genética , Cinética , Nicotina/biossíntese , Oxigênio/metabolismo , Plantas Medicinais , Plantas Tóxicas , Escopolamina/biossíntese , Nicotiana/metabolismo
13.
Zhongguo Yao Xue Za Zhi ; 34(12): 802-4, 1999 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-11543355

RESUMO

OBJECTIVE: To probe the effects of space condition on medicinal plants. METHODS: The seeds of Datura innoxia Mill were put in a retrievable satellite. After returning earth, the isozymes of peroxidases, esterase and soluble proteins were studied. RESULTS: The peroxidase activity and the protein content of weightless group were lower than that of the earth controlled group, but these items of the hit group were higher than that of the earth controlled group. The electrophoresis patterns of isozymes and proteins of these three groups were similar. CONCLUSION: The effects of weightlessness and the high energy heavy ions were different on Datura innoxia, and the effects of space conditions were not enough to produce idiovariation in Datura innoxia.


Assuntos
Datura stramonium/metabolismo , Datura stramonium/efeitos da radiação , Íons Pesados , Plantas Medicinais , Plantas Tóxicas , Voo Espacial , Ausência de Peso , Radiação Cósmica , Esterases/metabolismo , Isoenzimas/metabolismo , Peroxidases/metabolismo , Proteínas de Plantas/metabolismo , Sementes/metabolismo , Sementes/efeitos da radiação
14.
Phytochemistry ; 52(5): 871-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10626376

RESUMO

The enzymes N-methylputrescine oxidase (MPO), the tropine-forming tropinone reductase (TRI), the pseudotropine-forming tropinone reductase (TRII), the tropine:acyl-CoA transferase (TAT) and the pseudotropine:acyl-CoA transferase (PAT) extracted from transformed root cultures of Datura stramonium and a Brugmansia candida x aurea hybrid were tested for their ability to accept a range of alternative substrates. MPO activity was tested with N-alkylputrescines and N-alkylcadaverines as substrates. TRI and TRII reduction was tested against a series of N-alkylnortropinones, N-alkylnorpelletierines and structurally related ketones as substrates. TAT and PAT esterification tests used a series of N-substituted tropines, pseudotropines, pelletierinols and pseudopelletierinols as substrates to assess the formation of their respective acetyl and tigloyl esters. The results generally show that these enzymes will accept alien substrates to varying degrees. Such studies may shed some light on the overall topology of the active sites of the enzymes concerned.


Assuntos
Datura stramonium/enzimologia , Plantas Medicinais , Plantas Tóxicas , Tropanos/metabolismo , Datura stramonium/metabolismo , Cromatografia Gasosa-Espectrometria de Massas/métodos , Raízes de Plantas/enzimologia , Raízes de Plantas/metabolismo , Putrescina/análogos & derivados , Putrescina/metabolismo , Especificidade por Substrato
15.
J Int Med Res ; 23(2): 132-7, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-7601297

RESUMO

A case of acute poisoning by ingestion of Datura stramonium infusion is reported. The patient presented with a typical anticholinergic syndrome (dryness of mouth, mydriasis, flushing, tachycardia, agitation, hallucinations) and was treated with symptomatic and supportive measures. The presence of tropane belladona alkaloids in a urine sample was demonstrated by gas chromatography-mass spectrometry.


Assuntos
Alcaloides de Belladona/urina , Datura stramonium/metabolismo , Intoxicação por Plantas/urina , Plantas Medicinais , Plantas Tóxicas , Adolescente , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Masculino
16.
Jpn J Pharmacol ; 66(2): 195-204, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7532733

RESUMO

The N-acetyl glucosamine (GlcNAc)-specific lectin Datura stramonium agglutinin (DSA) rapidly and sugar-specifically released histamine from rat peritoneal mast cells, and pertussis toxin (IAP) inhibited it, suggesting that DSA activated mast cells via an IAP-sensitive G protein pathway. The additive effects of DSA and basic secretagogues such as compound 48/80 that activate IAP-sensitive G protein directly suggest that they shared the same mechanism of action including involvement of the IAP-sensitive G protein. Using lectin-blotting, blots of the corresponding glycoproteins detected by DSA diminished by haptenic sugar or pretreatment of the cells with N-glycosidase F, suggesting that the binding of DSA was responsible for the mast cell activation. The other GlcNAc-specific lectins such as Phytolacca americana mitogen, Solanum tuberosum agglutinin and wheat germ agglutinin (WGA) inhibited the histamine release induced by DSA, suggesting that these lectins were antagonists, but DSA was an agonist. Sialic acid-specific Macckia amurensis mitogen (MAM) inhibited the histamine release, and neuraminidase-treatment decreased mast cell activation induced by DSA. At least four mast cell glycoproteins that have affinity to DSA, WGA and MAM and are sensitive to neuraminidase-treatment were detected by lectin-blotting. Some of them may be binding sites coupled to histamine release including the IAP-sensitive G protein pathway. DSA is a useful tool for studying signal transduction of mast cells including the involvement of the IAP-sensitive G protein.


Assuntos
Acetilglucosamina/metabolismo , Liberação de Histamina/efeitos dos fármacos , Lectinas/farmacologia , Mastócitos/metabolismo , Aglutininas/farmacologia , Animais , Bradicinina/farmacologia , Datura stramonium/metabolismo , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Proteínas de Ligação ao GTP/metabolismo , Glicoproteínas/metabolismo , Haptenos/farmacologia , Immunoblotting , Masculino , Mastócitos/efeitos dos fármacos , Neuraminidase/farmacologia , Oligossacarídeos/farmacologia , Cavidade Peritoneal/citologia , Toxina Pertussis , Lectinas de Plantas , Plantas Medicinais , Plantas Tóxicas , Polietilenoimina/farmacologia , Ratos , Ratos Sprague-Dawley , Fatores de Virulência de Bordetella/farmacologia , p-Metoxi-N-metilfenetilamina/farmacologia
17.
Jpn J Pharmacol ; 66(2): 205-11, 1994 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7532734

RESUMO

A confocal fluorescence microscope using fluo-3 and 9-(dicyanovinyl)- julolidine (DCVJ) was used to study the mast cell activation by the N-acetyl glucosamine oligomer specific lectin Datura stramonium agglutinin (DSA) and inhibition by antagonist lectins having affinity to N-acetyl glucosamine (GlcNAc). DSA induced a transient increase in intracellular free calcium concentration ([Ca2+]i) followed by cytoskeletal disassembly and reassembly in rat peritoneal mast cells. These changes induced by DSA resulted in histamine release. The time course of fluorescence intensity in mast cells loaded with fluo-3- or DCVJ and activated by DSA resembled those activated by the basic polymer compound 48/80. Inhibition of [Ca2+]i rise by antagonist lectins was responsible for the inhibition of cytoskeletal assembly and the consequent histamine release induced by DSA. At the level of the individual cell, a mast cell stimulated by DSA responds in an all-or-none fashion. DSA possible induced intracellular calcium mobilization and cytoskeletal change by recognizing the GlcNAc-oligomer residues of specific glycoproteins of mast cells.


Assuntos
Datura stramonium/metabolismo , Liberação de Histamina/efeitos dos fármacos , Lectinas/farmacologia , Mastócitos/efeitos dos fármacos , Plantas Medicinais , Plantas Tóxicas , Aglutininas/farmacologia , Animais , Cálcio/metabolismo , Citoesqueleto/efeitos dos fármacos , Masculino , Mastócitos/metabolismo , Mastócitos/ultraestrutura , Microscopia Confocal , Microscopia de Fluorescência , Cavidade Peritoneal/citologia , Lectinas de Plantas , Ratos , Ratos Sprague-Dawley , p-Metoxi-N-metilfenetilamina/farmacologia
18.
Phytochemistry ; 37(2): 391-400, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7765621

RESUMO

In tropane-alkaloid producing plants and root cultures, the reduction of tropinone is a branch-point in secondary metabolism. Two different reductases stereospecifically form the isomeric alcohols tropine (tropan-3 alpha-ol) and pseudotropine (tropan-3 beta-ol). We describe here the purification and characterization of both reductases from transformed root cultures of Datura stramonium. The tropine-forming reductase (TR I, EC 1.1.1.206) was purified 108-fold, the pseudotropine-forming enzyme (TR II, EC 1.1.1.236) was purified 3410-fold to homogeneity. The native molecular weights, both determined by gel chromatography, were 50,700 (TR I) and 77,700 (TR II). In SDS gel electrophoresis a subunit with an M(r) of 27,700 could be identified for TR II. Isoelectric points are at 5.2 (TR I) and 5.7 (TR II). Km values for the physiological substrate tropinone are 1.30 mM (TR I) and 0.11 mM (TR II). NADPH as a cosubstrate shows Km values of 58 microM (TR I) and 16 microM (TR II). NADH is not accepted by either enzyme. The reverse reaction (i.e. oxidation of the alcohol to tropinone) was found only for TR I with a Km of 180 microM. From a detailed analysis of the catalytic activities of TR I and TR II with a range of substrate analogues some key features of the mechanism of reaction can be proposed. The catalytic properties of TR I and TR II are compared with each other and with TR I and TR II activities from other solanaceous species from which these enzymes have been described.


Assuntos
Oxirredutases do Álcool/metabolismo , Datura stramonium/metabolismo , Plantas Medicinais , Plantas Tóxicas , Tropanos/metabolismo , Oxirredutases do Álcool/química , Oxirredutases do Álcool/isolamento & purificação , Catálise , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Eletroforese em Gel de Poliacrilamida , Peso Molecular , Oxirredução , Especificidade por Substrato
20.
FEBS Lett ; 292(1-2): 293-7, 1991 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-1959620

RESUMO

Tropine (tropan-3 alpha-ol) is an intermediate in the formation of hyoscyamine. An acyltransferase activity that can acetylate tropine using acetylcoenzyme A as cosubstrate has been found in transformed root cultures of Datura stramonium. A further acyltransferase activity that acetylates pseudotropine (tropan-3 beta-ol) with acetyl-coenzyme A is also present. These two activities can be partially resolved by anion-exchange chromatography, some fractions containing only the pseudotropine-utilizing activity. The basic properties of these two enzymes are reported and their roles in forming the observed alkaloid spectrum of D. stramonium roots discussed.


Assuntos
Acetiltransferases/metabolismo , Datura stramonium/metabolismo , Plantas Medicinais , Plantas Tóxicas , Tropanos/metabolismo , Acetiltransferases/isolamento & purificação , Atropina/biossíntese , Cromatografia por Troca Iônica , Concentração de Íons de Hidrogênio
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