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1.
Sci Rep ; 7(1): 16653, 2017 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-29192145

RESUMO

Animals self-medicate using a variety of plant and arthropod secondary metabolites by either ingesting them or anointing them to their fur or skin apparently to repel ectoparasites and treat skin diseases. In this respect, much attention has been focused on primates. Direct evidence for self-medication among the great apes has been limited to Africa. Here we document self-medication in the only Asian great ape, orang-utans (Pongo pygmaeus), and for the first time, to our knowledge, the external application of an anti-inflammatory agent in animals. The use of leaf extracts from Dracaena cantleyi by orang-utan has been observed on several occasions; rubbing a foamy mixture of saliva and leaf onto specific parts of the body. Interestingly, the local indigenous human population also use a poultice of these leaves for the relief of body pains. We present pharmacological analyses of the leaf extracts from this species, showing that they inhibit TNFα-induced inflammatory cytokine production (E-selectin, ICAM-1, VCAM-1 and IL-6). This validates the topical anti-inflammatory properties of this plant and provides a possible function for its use by orang-utans. This is the first evidence for the deliberate external application of substances with demonstrated bioactive potential for self-medication in great apes.


Assuntos
Comportamento Animal , Produtos Biológicos , Dracaena/química , Plantas Medicinais , Pongo pygmaeus , Automedicação , Animais , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Biomarcadores , Linhagem Celular , Citocinas/metabolismo , Dracaena/metabolismo , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia
2.
Plant Biol (Stuttg) ; 17(6): 1146-55, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26177040

RESUMO

A better understanding of phytohormone physiology can provide an essential basis to coherently achieve a conservation drive/strategy for valuable plant species. We evaluated the distribution pattern of cytokinins (CKs) and phenolic compounds in different organs of 1-year-old greenhouse-grown Tulbaghia simmleri pre-treated (during micropropagation) with three aromatic CKs (benzyladenine = BA, meta-topolin = mT, meta-topolin riboside = mTR). The test species is highly valuable due to its medicinal and ornamental uses. Based on UHPLC-MS/MS quantification, mT and mTR pre-treated plants had the highest total CK, mostly resulting from the isoprenoid CK-type, which occurred at highest concentrations in the roots. Although occurring in much lower concentrations when compared to isoprenoid CKs, aromatic CKs were several-fold more abundant in the root of mT pre-treated plants than with other treatments. Possibly related to the enhanced aromatic CKs, free bases and ribonucleotides, plants pre-treated with mT generally displayed better morphology than the other treatments. A total of 12 bioactive phenolic compounds, including four hydroxybenzoic acids, five hydroxycinnamic acids and three flavonoids at varying concentrations, were quantified in T. simmleri. The occurrence, distribution and levels of these phenolic compounds were strongly influenced by the CK pre-treatments, thereby confirming the importance of CKs in phenolic biosynthesis pathways.


Assuntos
Ácidos Cumáricos/metabolismo , Citocininas/farmacologia , Flavonoides/metabolismo , Hidroxibenzoatos/metabolismo , Liliaceae/efeitos dos fármacos , Reguladores de Crescimento de Plantas/farmacologia , Raízes de Plantas/efeitos dos fármacos , Citocininas/metabolismo , Liliaceae/metabolismo , Fenóis/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/metabolismo
3.
J Plant Physiol ; 169(18): 1830-7, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22985989

RESUMO

Caulogenesis in mature stone pine (Pinus pinea L.) cotyledons is promoted, to varying degrees depending on genotype, by exogenous application of the cytokinin (CK) benzyladenine (BA). In the present study, endogenous CK profiles of cotyledons from open-pollinated plants and two families of stone pine with widely differing organogenic capacities were monitored during caulogenesis and linked to previously characterized BA uptake and induction phases. Changes in levels of free bases, ribosides, ribotides and glucosides of both isoprenoid and aromatic CKs were followed. Before BA application, the pool of endogenous CKs in all sets of cotyledons was dominated by isoprenoid ribotides, but 1h after BA exposure, aromatic CKs (mainly active free bases and ribosides of topolins) accounted for more than 90% of the pool. BA N-glucosides were also observed, levels of which (and topolins) rose from 2d until the end of the (six-day) culture period. The CK profiles of the two selected pine families also differed, although the general trends were similar. During the first 6h, levels of BA and meta-topolin were highest in cotyledons from the family with the strongest caulogenic responses, while levels of ribotides and aromatic glucosides were highest in cotyledons from the other family.


Assuntos
Cotilédone/metabolismo , Citocininas/metabolismo , Pinus/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Derivados de Benzeno/farmacologia , Cotilédone/crescimento & desenvolvimento , Citocininas/análise , Citocininas/isolamento & purificação , Regulação da Expressão Gênica de Plantas , Genótipo , Glucosídeos/metabolismo , Pinus/crescimento & desenvolvimento , Reguladores de Crescimento de Plantas/análise , Reguladores de Crescimento de Plantas/isolamento & purificação , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Técnicas de Embriogênese Somática de Plantas , Especificidade da Espécie , Terpenos/metabolismo , Fatores de Tempo
4.
J Inorg Biochem ; 84(1-2): 23-32, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11330478

RESUMO

Copper(II) complexes of 6-(2-chlorobenzylamino)purine (HL1) and 6-(3-chlorobenzylamino)purine (HL2), respectively, were prepared. Depending on the pH of the medium and the molar ratio of reactants the following mononuclear (trigonal-bipyramidal) and dinuclear (octahedral, trigonal-bipyramidal or tetrahedral) complexes were isolated: [Cu2(mu-HL1)2(mu-Cl2)2(HL1)2Cl2] (1a,b), [Cu2(mu-Cl)2(mu-L1)2(H2O)2] (2a), [Cu2(mu-Cl)2(mu-L2)2(H2O)2] (2b), [Cu(H+L2)2Cl3]Cl.H2O (3a,b), [Cu2(mu-Cl)2(HL1)2Cl2] (4a), and [Cu2(mu-Cl)2(HL2)2Cl2] (4b). The compounds were characterized by elemental analyses, electronic, infrared and mass (FAB+, ES+) spectral data, magnetic susceptibility temperature dependence measurements and molar conductivity data. An X-ray single-crystal structural analysis of [Cu(H+L2)2Cl3]Cl.2H2O (3b) showed that the Cu2+ ion is penta-coordinated by three chloride ions and by two H+L2 ligands. Thus, the Cu2+ ion adopts a distorted trigonal bipyramidal coordination geometry with the protonated H+L2 ligands coordinated in trans apical positions, while the three chloride ions are situated in an equatorial plane. The cytotoxic activity of the complexes was determined by a calcein AM assay. Mouse melanoma cell line B16-FO, human malignant melanoma cell line G361, human osteogenic sarcoma cell line HOS and human breast adenocarcinoma cell line MCF7 were used. IC50 values, the drug concentrations lethal to 50% of the tumor cells, were estimated. One of the important mechanisms responsible for the cytotoxicity of cytokinin-derived compounds, the inhibition of cyclin-dependent kinases by the studied complexes, was also determined.


Assuntos
Cobre/química , Cobre/farmacologia , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Purinas/química , Purinas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Cristalografia por Raios X , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Dose Letal Mediana , Camundongos , Modelos Moleculares , Compostos Organometálicos/síntese química , Purinas/síntese química , Células Tumorais Cultivadas
5.
Artigo em Polonês | MEDLINE | ID: mdl-12818137

RESUMO

The aim of the study was to estimate growth curve and body mass during and after a treatment of ALL. Retrospective study group included 48 children (27 boys and 21 girls). The age at the start of the treatment varied from 1.4 up 17 years, during our evaluation 4.6-25.4 years. Patients were treated according to modified American (New York Protocol) and German (BFM) protocols. 43 children received central nervous system radiation in a dose of 14-24 Gy. All children completed the treatment protocol and are in the remission. Growth velocity and body mass were estimated during and after the ALL treatment. During the treatment growth retardation was observed at 34 children (2/3 patients). No significant difference in growth velocity was found between group of standard and high risk of ALL. Combined radiotherapy and chemotherapy has probably more influence for growth retardation than chemotherapy alone. Obesity was stated at 13 patients (27%), mostly boys. After the treatment 9 children were permanently obese. Body mass deficiency was found at 5 patients during the treatment and was the same when the treatment protocol was completed.

6.
Proc Natl Acad Sci U S A ; 97(26): 14778-83, 2000 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-11114204

RESUMO

Studies of de novo cytokinin biosynthesis in isopentenyltransferase (ipt)-transformed Arabidopsis thaliana, involving in vivo deuterium labeling and mass spectrometry, showed that the biosynthetic rate of zeatinriboside-5'-monophosphate was around 66-fold higher than that of isopentenyladenosine-5'-monophosphate (iPMP), the proposed primary product of the Agrobacterium ipt. Double tracer analysis, using [(2)H(6)] isopentenyladenosine and deuterium oxide, provided evidence for an alternative, iPMP-independent, biosynthetic pathway for zeatin-type cytokinins, present in both ipt-expressing and wild-type Arabidopsis thaliana. Reduction of the biosynthetic flux in the alternative pathway by use of mevastatin, an inhibitor for 3-hydroxy-3-methylglutaryl CoA reductase, indicated a terpenoid origin for the side-chain precursor of the iPMP independent pathway.


Assuntos
Citocininas/biossíntese , Alquil e Aril Transferases/genética , Arabidopsis , Citocromos , Deutério , Expressão Gênica , Marcação por Isótopo , Terpenos
7.
J Mass Spectrom ; 35(1): 13-22, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10633230

RESUMO

A method was developed for analysing the biosynthetic rate of the cytokinin class of plant hormones. Transgenic, cytokinin-overproducing Arabidopsis thaliana plants were incubated in liquid culture media enriched with 30% deuterium oxide, and incorporation into the different parts of the cytokinin molecule was analysed by capillary liquid chromatography/frit-fast atom bombardment mass spectrometry after precolumn propionylation. The sugar moieties of the cytokinins generally showed a high and independent incorporation, so the analysis in this study focused on the cytokinin base moieties. It was observed that during a 24 h incubation period almost all labelling was incorporated into the side-chain, rather than the adenine moiety. The incorporation dynamics of isopentenyladenosine-5'-monophosphate, zeatinriboside-5'-monophosphate (ZRMP) and zeatin-9-glucoside were investigated through analysis of the cytokinin base fragments in high-resolution selective ion monitoring mode. Using a fractional synthetic rate approach, the biosynthetic rate of ZRMP was determined to be 18 ng h(-1) g(-1) fresh weight, giving a turnover time of 25 h. A method for the mass isotopomer abundance analysis of the cytokinins in the zeatin family, based on selective reaction monitoring, was also developed to gain further sensitivity. Use of this technique showed that there was a higher level of enrichment in zeatin nucleotide than in the corresponding nucleoside, in agreement with the hypothesis that cytokinin nucleotides are primary products in this pathway.


Assuntos
Arabidopsis/química , Cromatografia Líquida/métodos , Citocininas/análise , Espectrometria de Massas de Bombardeamento Rápido de Átomos/métodos , Deutério , Marcação por Isótopo
8.
J Mass Spectrom ; 33(9): 892-902, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9768500

RESUMO

New cytokinin derivatives with high surface activity were developed for capillary liquid chromatography/frit-fast atom bombardment (FAB) mass spectrometry. Propionyl ester derivatives of cytokinin nucleosides and glucosides and benzylamine derivatives of cytokinin bases gave stronger [M + H]+ ion currents than the underivatized compounds. In trace analysis by selective reaction monitoring, low (fmole) detection limits were found. In qualitative analysis by B/E-linked scanning, the derivatives also gave more spectral information, owing to the presence of fragment ions, diagnostic for the sugar moieties of nucleosides and glucosides, not present in the spectra of underivatized compounds. THe proposed FAB method was used to identify and quantify 10 isoprenoid cytokinins in Arabidopsis thaliana, including free bases, nucleosides, nucleotides and glucosides.


Assuntos
Arabidopsis/química , Citocininas/análise , Espectrometria de Massas de Bombardeamento Rápido de Átomos/métodos , Cromatografia Líquida , Modelos Químicos , Fosfatos de Poli-Isoprenil/análise
9.
Folia Histochem Cytobiol ; 30(2): 75-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1483537

RESUMO

Distribution of calcium and phosphorus was investigated with quantitative and qualitative methods in teeth of rats chronically treated with low doses of corticosteroids for 3 generations. In animals from 2nd and 3rd generation, scanning electron microscopy revealed focal lesions in enamel and dentin. The disturbances of the mineral metabolism in teeth of corticosteroid-treated rats were also reflected by abnormal calcium and phosphorus content in enamel and dentin, as assessed by X-ray microanalysis.


Assuntos
Corticosteroides/toxicidade , Cálcio/metabolismo , Fósforo/metabolismo , Efeitos Tardios da Exposição Pré-Natal , Dente/metabolismo , Animais , Esmalte Dentário/efeitos dos fármacos , Esmalte Dentário/metabolismo , Dentina/efeitos dos fármacos , Dentina/metabolismo , Feminino , Masculino , Gravidez , Ratos , Ratos Wistar , Fatores de Tempo , Distribuição Tecidual , Dente/efeitos dos fármacos
17.
Artigo em Inglês | MEDLINE | ID: mdl-7160785

RESUMO

The experiments were carried out on Wistar rats with rickets experimentally induced. The following examinations were made: radiological examinations of the jaws, a teeth analysis in the microanalyser for the distribution of fundamental elements, and ultrastructure observations in the scanning electron microscope. The jaws of the experimental rats were smaller in the radiological picture. The disturbed arrangement of the enamel prisms was found in the enamel substructure of the experimental rats. Phosphorus values in the enamel and dentine were lower in the experimental animals. Calcium to phosphorus ratio was higher in the rachitic rats. Disturbances of calcium-phosphorus balance were observed.


Assuntos
Cálcio/análise , Esmalte Dentário/análise , Dentina/análise , Fósforo/análise , Raquitismo/metabolismo , Animais , Esmalte Dentário/ultraestrutura , Microanálise por Sonda Eletrônica , Magnésio/análise , Mandíbula/diagnóstico por imagem , Radiografia , Ratos , Ratos Endogâmicos , Raquitismo/patologia
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