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1.
Cells ; 12(14)2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37508498

RESUMO

Plant primary cell walls are composite structures surrounding the protoplast and containing pectins, hemicelluloses, and cellulose polysaccharides, as well as proteins. Their composition changed during the evolution of the green lineage from algae to terrestrial plants, i.e., from an aquatic to a terrestrial environment. The constraints of life in terrestrial environments have generated new requirements for the organisms, necessitating adaptations, such as cell wall modifications. We have studied the cell wall polysaccharide composition of thalli of Marchantia polymorpha, a bryophyte belonging to one of the first land plant genera. Using a collection of specific antibodies raised against different cell wall polysaccharide epitopes, we were able to identify in polysaccharide-enriched fractions: pectins, including low-methylesterified homogalacturonans; rhamnogalacturonan I with arabinan side-chains; and hemicelluloses, such as xyloglucans with XXLG and XXXG modules, mannans, including galactomannans, and xylans. We could also show the even distribution of XXLG xyloglucans and galactomannans in the cell walls of thalli by immunocytochemistry. These results are discussed with regard to the cell wall proteome composition and in the context of the evolution of the green lineage. The cell wall polysaccharides of M. polymorpha illustrate the transition from the charophyte ancestors of terrestrial plants containing xyloglucans, xylans and mannans as hemicelluloses, and embryophytes which do not exhibit mannans as major primary cell wall polysaccharides.


Assuntos
Embriófitas , Marchantia , Xilanos/metabolismo , Marchantia/metabolismo , Mananas/metabolismo , Polissacarídeos/metabolismo , Pectinas/metabolismo , Embriófitas/química , Embriófitas/metabolismo , Plantas/metabolismo , Parede Celular/metabolismo
2.
Plant J ; 109(3): 568-584, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34767672

RESUMO

Charophyte green algae (CGA) are assigned to be the closest relatives of land plants and therefore enlighten processes in the colonization of terrestrial habitats. For the transition from water to land, plants needed significant physiological and structural changes, as well as with regard to cell wall composition. Sequential extraction of cell walls of Nitellopsis obtusa (Charophyceae) and Spirogyra pratensis (Zygnematophyceae) offered a comparative overview on cell wall composition of late branching CGA. Because arabinogalactan-proteins (AGPs) are considered common for all land plant cell walls, we were interested in whether these special glycoproteins are present in CGA. Therefore, we investigated both species with regard to characteristic features of AGPs. In the cell wall of Nitellopsis, no hydroxyproline was present and no AGP was precipitable with the ß-glucosyl Yariv's reagent (ßGlcY). By contrast, ßGlcY precipitation of the water-soluble cell wall fraction of Spirogyra yielded a glycoprotein fraction rich in hydroxyproline, indicating the presence of AGPs. Putative AGPs in the cell walls of non-conjugating Spirogyra filaments, especially in the area of transverse walls, were detected by staining with ßGlcY. Labelling increased strongly in generative growth stages, especially during zygospore development. Investigations of the fine structure of the glycan part of ßGlcY-precipitated molecules revealed that the galactan backbone resembled that of AGPs with 1,3- 1,6- and 1,3,6-linked Galp moieties. Araf was present only in small amounts and the terminating sugars consisted predominantly of pyranosidic terminal and 1,3-linked rhamnose residues. We introduce the term 'rhamnogalactan-protein' for this special AGP-modification present in S. pratensis.


Assuntos
Evolução Biológica , Parede Celular/química , Embriófitas/química , Galactanos/química , Mucoproteínas/química , Proteínas de Plantas/química , Spirogyra/química , Spirogyra/genética , Carofíceas/química , Carofíceas/genética , Galactanos/genética , Mucoproteínas/genética , Proteínas de Plantas/genética
3.
Carbohydr Polym ; 277: 118764, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34893214

RESUMO

Sulphated polysaccharides (SPs) are carbohydrate macromolecules with sulphate esters that are found among marine algae, seagrasses, mangroves and some terrestrial plants. The sulphate concentration in the ocean (28 mM) since ancient time could have driven the production of SPs in marine algae. SPs have a gelatinous property that can protect marine algae against desiccation and salinity stress. Agar and carrageenan are red algal SPs that are widely used as gelling agents in the food and pharmaceutical industries. The information on the SPs from freshwater and land plants are limited. In this review, we reviewed the taxonomic distribution and composition of SPs in different photosynthetic lineages, and explored the association of SP production in these diversified photosynthetic organisms with evolution history and environmental stresses. We also reviewed the genes/proteins involved in SP biosynthesis. Insights into SP biosynthetic machinery may shed light on the evolution that accompanied adaptation to life on earth.


Assuntos
Polissacarídeos/biossíntese , Sulfatos/metabolismo , Embriófitas/química , Embriófitas/metabolismo , Água Doce/química , Processos Fotoquímicos , Polissacarídeos/química , Sulfatos/química
4.
Photosynth Res ; 144(2): 221-233, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32052255

RESUMO

The kinetics of excited-state energy migration were investigated by femtosecond transient absorption in the isolated Photosystem I-Light-Harvesting Complex I (PSI-LHCI) supercomplex and in the isolated PSI core complex of spinach under conditions in which the terminal electron donor P700 is chemically pre-oxidised. It is shown that, under these conditions, the relaxation of the excited state is characterised by lifetimes of about 0.4 ps, 4.5 ps, 15 ps, 35 ps and 65 ps in PSI-LHCI and 0.15 ps, 0.3 ps, 6 ps and 16 ps in the PSI core complex. Compartmental spectral-kinetic modelling indicates that the most likely mechanism to explain the absence of long-lived (ns) excited states is the photochemical population of a radical pair state, which cannot be further stabilised and decays non-radiatively to the ground state with time constants in the order of 6-8 ps.


Assuntos
Complexos de Proteínas Captadores de Luz/química , Complexo de Proteína do Fotossistema I/química , Proteínas de Plantas/química , Clorofila/química , Embriófitas/química , Embriófitas/metabolismo , Transferência de Energia , Cinética , Complexos de Proteínas Captadores de Luz/metabolismo , Oxirredução , Complexo de Proteína do Fotossistema I/metabolismo , Proteínas de Plantas/metabolismo , Análise Espectral/métodos , Spinacia oleracea/química
5.
Chem Biodivers ; 17(3): e1900663, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31943724

RESUMO

Asteraceae plants from arid lands are a source of biomass, resin and latex rich in terpenoids with diverse biological effects. Thirty-six previously isolated terpenes, comprising sesquiterpenes, diterpenes, triterpenes and quassinoids, isolated from arid-land plants and a series of metabolites from the biotransformation of some lead compounds were evaluated against insect pests (Spodoptera littoralis, Leptinotarsa decemlineata, Myzus persicae and Rhopalosiphum padi), cells (insect, hamster, murine and human tumoral cells) and parasites (Trypanosoma cruzi and Leishmania infantum). Among the insecticidal sesquiterpenes, maalian-1α,8α-diol (12) and γ-eudesmol (17) were antifeedant against L. decemlineata, M. persicae and cytotoxic to Sf9 insect cells, and (-)-maali-3-en-8α-ol (10), (+)-maaliane-5α,8α,9α-triol (11), chrysothame (31) and holacanthone (35) were antifeedant against S. littoralis. The parasite L. infantum was slightly more sensitive than T. cruzi to the test compounds (39 % vs. 33 % of active compounds) with compound 17 and the biotransformed diterpene 27 being antiparasitic to L. infantum, with no cytotoxic effects on mammalian cells. Moreover, sesquiterpenes 3 and 17, and grindelane diterpenes 22, 23 and 26 showed selective activity against chemoresistant human colon, cervical and melanoma cancer cells. Thus, considering our results, the best candidates for future studies are compounds 17 and 3, due to their activity on insect pests, parasites (17) and tumoral cells (3, 17, 22, 23 and 26).


Assuntos
Antineoplásicos/farmacologia , Antiprotozoários/farmacologia , Asteraceae/química , Embriófitas/química , Inseticidas/farmacologia , Terpenos/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Insetos/efeitos dos fármacos , Inseticidas/química , Inseticidas/isolamento & purificação , Leishmania infantum/efeitos dos fármacos , Conformação Molecular , Relação Estrutura-Atividade , Terpenos/química , Terpenos/isolamento & purificação , Trypanosoma cruzi/efeitos dos fármacos
6.
Carbohydr Polym ; 231: 115732, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31888819

RESUMO

Cibotium barometz, an important traditional Chinese medicine, is used in strengthening bones and tendons. We found that C. barometz crude polysaccharides (CB70) could alleviate bone loss and markedly improve the biomechanical properties of OVX rats. Thus, to clarify biological active ingredient(s) of CB70, two homogeneous polysaccharides (CBP70-1-1 and CBP70-1-2) were purified from CB70. A combination of monosaccharide composition, FT-IR, GC-MS and NMR analysis indicated that CBP70-1-1 was composed of →6)-D-Galp-(1→, D-Glcp-(1→, →3,6)-D-Manp-(1→, →4)-D-Glcp-(1→ and →6)-D-Glcp-(1→ with relative molecular weights of 12,724 Da, and CBP70-1-2 was composed of →4)-D-Glcp-(1→, D-Glcp-(1→, →3,6)-D-Manp-(1→, →6)-D-Galp-(1→, →4,6)-D-Glcp-(1→ and →3)-L-Araf-(1→ with relative molecular weights of 3611 Da. Morphological analyses revealed that CBP70-1-1 and CBP70-1-2 appeared as a sheet that were irregular in size and shape, while the surface of CBP70-1-1 was full of sharp protuberances and CBP70-1-2 was smooth. Furthermore, the effects of CBP70-1-1 and CBP70-1-2 on the proliferation, differentiation and mineralization of mouse pre-osteoblastic MC3T3-E1 cells were assessed via CCK-8 assay, alkaline phosphatase activity assay, and alizarin red-based assay, respectively. These results revealed that CBP70-1-1 and CBP70-1-2 significantly promoted the proliferation, differentiation and mineralization of MC3T3-E1 cells, even better than E2. More importantly, quantitative real-time PCR and Western blot analysis indicated that CBP70-1-2 pronouncedly promoted the expression of osteogenic-related marker genes (Runx2, Osx, Ocn and Opn) and proteins (BMP2, RUNX2, OSX and p-SMAD1), which implies that the osteogenic activity of CBP70-1-2 is accomplished mainly by activating the BMP2/SMAD1 signaling pathway. These findings suggest CBP70-1-2 as a potential natural anti-osteoporotic agent for pharmacotherapy.


Assuntos
Embriófitas/química , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Polissacarídeos/química , Células 3T3 , Animais , Proteína Morfogenética Óssea 2/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Camundongos , Osteoporose/patologia , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Rizoma/química , Transdução de Sinais/efeitos dos fármacos , Proteína Smad1/genética , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Recent Pat Biotechnol ; 14(1): 16-32, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31438835

RESUMO

BACKGROUND: Recently, it has been established that simultaneous saccharification and fermentation is a potent technique for the detoxification of harmful plant materials. OBJECTIVE: Following encouraging simultaneous medicinal applications of snail slime and yeast, we exploited their hydrolytic and fermentation potentials to prevent toxicities of the selected floras; Erythrodontium barteri (EB), bracken fern (BF), and crustose lichens (CL). The applicability of the saccharification process has been described in a patent (WO2005010193A2). METHODS: The plants were bioprocessed using snail digestive juice and yeast slurry and their health effects were evaluated. Seventy rats were divided equally into groups, treated with single doses of aqueous extracts of the plants and their bioprocessed forms, and compared with control rats. RESULTS: The plants showed very high antinutrients levels, which significantly reduced after SSF with enhanced flavonoids, alkaloids and phenols. Potential alterations of WBC differentials, RBC, liver and renal function markers indices were mitigated by bioprocessed extracts. MDA, SOD, GRase, XO and XDH levels in rats administered the bEB and CL were equivalent to the levels found for the control rats. Some bioprocessed plants produced unaltered insulin, ghrelin, and leptin levels. The bioprocessed extracts, when compared to the effects of unprocessed extracts, produced lower TNF-α, Caspase-3, and adiponectin levels and mitigated the potential suppression of Na+/K+-ATPase levels. Potential depletion of inhibin-B, testosterone, estrogen, and prolactin was mitigated after bioprocessing. CONCLUSION: This study, thus, validates the application of bioprocessing using snail digestive juice and yeast as an effective approach to reduce the potential toxicities of harmful plants.


Assuntos
Produtos Biológicos , Fígado , Extratos Vegetais , Animais , Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Biotransformação , Glicemia/efeitos dos fármacos , Embriófitas/química , Feminino , Testes Hematológicos , Líquens/química , Fígado/efeitos dos fármacos , Fígado/enzimologia , Fígado/patologia , Masculino , Estresse Oxidativo/efeitos dos fármacos , Patentes como Assunto , Extratos Vegetais/química , Extratos Vegetais/metabolismo , Extratos Vegetais/farmacocinética , Extratos Vegetais/toxicidade , Ratos , Ratos Wistar , Caramujos/química , Leveduras/química
8.
Prog Chem Org Nat Prod ; 109: 385-413, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31637530

RESUMO

Since higher plants are unable to move in their environment, interesting and mysterious developmental events (allelopathy, phototropism, apical dominance, nyctinasty, flowering, senescence) are observed in their life cycle. Chemical compounds released from plant organs to the neighboring environment stimulate or suppress the development and/or growth of other plants; this chemical interaction is called "allelopathy." The bending of the organs of a plant toward the light is a well-known phenomenon called "phototropism." The growth of lateral buds of some plants is normally repressed by a strongly growing main shoot apex and is the so-called "apical dominance". Plants open their leaves during the day and close them at night as if sleeping is known as "nyctinasty." Herein, recent studies on isolation and structure elucidation of bioactive compounds involved in their life cycle and determination of the molecular mechanisms for these developmental events are described.


Assuntos
Embriófitas/química , Fototropismo , Compostos Fitoquímicos/análise , Animais , Embriófitas/crescimento & desenvolvimento , Folhas de Planta/crescimento & desenvolvimento
9.
J Exp Bot ; 70(14): 3467-3494, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31305901

RESUMO

The colonization of the atmosphere by land plants was a major evolutionary step. The mechanisms that allow for vertical growth through air and the establishment and control of a stable erect habit are just starting to be understood. A key mechanism was found to be continuous posture control to counterbalance the mechanical and developmental challenges of maintaining a growing upright structure. An interdisciplinary systems biology approach was invaluable in understanding the underlying principles and in designing pertinent experiments. Since this discovery previously held views of gravitropic perception had to be reexamined and this has led to the description of proprioception in plants. In this review, we take a purposefully pedagogical approach to present the dynamics involved from the cellular to whole-plant level. We show how the textbook model of how plants sense gravitational force has been replaced by a model of position sensing, a clinometer mechanism that involves both passive avalanches and active motion of statoliths, granular starch-filled plastids, in statocytes. Moreover, there is a transmission of information between statocytes and other specialized cells that sense the degree of organ curvature and reset asymmetric growth to straighten and realign the structure. We give an overview of how plants have used the interplay of active posture control and elastic sagging to generate a whole range of spatial displays during their life cycles. Finally, a position-integrating mechanism has been discovered that prevents directional plant growth from being disrupted by wind-induced oscillations.


Assuntos
Embriófitas/química , Embriófitas/crescimento & desenvolvimento , Fenômenos Biomecânicos , Elasticidade , Embriófitas/fisiologia , Gravitropismo , Mecanotransdução Celular
10.
Sci Total Environ ; 663: 16-28, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30708213

RESUMO

The weathering of U and/or Th rich granite plutons, which occurs worldwide, may serve as a potentially important, but as yet poorly defined source for U and Th in (sub-)surface environments. Here, we assessed the impact of an outcrop of such granite (5 km in diameter) and its erosional products on the distribution of U and Th in four nemo-boreal catchments. The results showed that (i) the pluton was enriched in both U and Th; and (ii) secondary U and Th phases were accumulated by peat/gyttja and in other Quaternary deposits with high contents of organic matter. Movement of the ice sheet during the latest glaciation led to dispersal of U- and Th-rich materials eroded from the pluton, resulting in a progressive increase in dissolved U and Th concentrations, as well as U concentrations in aquatic plants with increasing proximity to the pluton. The accumulation of U in the aquatic plants growing upon the pluton (100-365 mg kg-1, dry ash weight) shows that this rock represents a long-term risk for adjacent ecosystems. Dissolved pools of U and Th were correlated with those of dissolved organic matter (DOM) and were predicted to largely occur as organic complexes. This demonstrates the importance of DOM in the transport of U and Th in the catchments. Large fractions of Ca2UO2(CO3)30(aq) were modeled to occur in the stream with highest pH and alkalinity and thus, explain the strongly elevated U concentrations and fluxes in this particular stream. In future climate scenarios, boreal catchments will experience intensified runoff and warmer temperature that favor the production of hydrologically accessible DOM and alkalinity. Therefore, the results obtained from this study have implications for predicting the distribution and transport of Th and U in boreal catchments, especially those associated with U and/or Th rich granite plutons.


Assuntos
Embriófitas/química , Sedimentos Geológicos/química , Rios/química , Tório/análise , Urânio/análise , Monitoramento Ambiental , Dióxido de Silício , Suécia
11.
Molecules ; 23(6)2018 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-29895732

RESUMO

We previously reported on the isolation and biological activities of plagiochiline A (1), a 2,3-secoaromadendrane-type sesquiterpenoid from the Peruvian medicinal plant, Plagiochila disticha. This compound was found to have antiproliferative effects on a variety of solid tumor cell lines, as well as several leukemia cell lines. Other researchers have also noted the cytotoxicity of plagiochiline A (isolated from different plant species), but there are no prior reports regarding the mechanism for this bioactivity. Here, we have evaluated the effects of plagiochiline A on cell cycle progression in DU145 prostate cancer cells. A cell cycle analysis indicated that plagiochiline A caused a significant increase in the percentage of cells in the G2/M phase when compared with control cells. When cells were stained and observed by fluorescence microscopy to examine progress through the mitotic phase, we found a significant increase in the proportion of cells with features of late cytokinesis (cells connected by intercellular bridges) in the plagiochiline A-treated samples. These results suggest that plagiochiline A inhibits cell division by preventing completion of cytokinesis, particularly at the final abscission stage. We also determined that plagiochiline A reduces DU145 cell survival in clonogenic assays and that it induces substantial cell death in these cells.


Assuntos
Citocinese/efeitos dos fármacos , Embriófitas/química , Compostos de Epóxi/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Piranos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Humanos , Masculino , Extratos Vegetais/química , Piranos/química , Piranos/isolamento & purificação
12.
Planta Med ; 84(11): 806-812, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29301145

RESUMO

Three diynes, octadec-17-ene-9,11-diynoate ethyl (1: ), 8-hydroxy-octadeca-13,17-diene-9,11-diynoate ethyl (2: ), and 8-hydroxy-octadec-13-ene-9,11-diynoate ethyl (3: ), were isolated from Ongokea gore seed oil. The structure assignment of these three compounds was based according to chemical and spectroscopic data. They were screened against Plasmodium falciparum, the parasite that causes malaria. In vitro micro-test (Mark III, supported by the World Health Organization) was developed to assess the response of P. falciparum to the isolated three compounds, and statistical analysis were performed for determination of the concentration that inhibits 50% of the parasite maturation (IC50). Two of the three diynes (2: and 3: ) showed a very effective in vitro antimalarial activity with an IC50 of 4.5 and 1.7 µM, respectively. Compound 3: exhibited better activity than quinine (IC50 1.9 µM), the drug reference, while compound 1: had no antimalarial activity (IC50 > 125 µM). In the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) cytotoxicity screening, all compounds showed no toxicity (mean IC50 of 90 µM for each compound).


Assuntos
Antimaláricos/farmacologia , Di-Inos/farmacologia , Embriófitas/química , Malária Falciparum/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Antimaláricos/química , Antimaláricos/isolamento & purificação , Pré-Escolar , Di-Inos/química , Di-Inos/isolamento & purificação , Humanos , Masculino , Óleos de Plantas/química , Sementes/química
13.
Philos Trans R Soc Lond B Biol Sci ; 373(1739)2018 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-29254964

RESUMO

Terrestrialization depended on the evolution of biosynthetic pathways for biopolymers including lignin, cutin and suberin, which were concentrated in specific tissues, layers or organs such as the xylem, cuticle and roots on the submillimetre scale. However, it is often difficult, or even impossible especially for individual cells, to resolve the biomolecular composition of the different components of fossil plants on such a scale using the well-established coupled techniques of gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. Here, we report the application of techniques for surface analysis to investigate the composition of Rhynia gwynne-vaughanii X-ray photoelectron spectroscopy of two different spots (both 300 µm × 600 µm) confirmed the presence of carbon. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) revealed 'chemical maps' (imaging mode with 300 nm resolution) of aliphatic and aromatic carbon in the intact fossil that correlate with the vascular structures observed in high-resolution optical images. This study shows that imaging ToF-SIMS has value for determining the location of the molecular components of fossil embryophytes while retaining structural information that will help elucidate how terrestrialization shaped the early evolution of land plant cell wall biochemistry.This article is part of a discussion meeting issue 'The Rhynie cherts: our earliest terrestrial ecosystem revisited'.


Assuntos
Carbono/análise , Embriófitas/química , Fósseis/diagnóstico por imagem , Paleontologia/métodos , Espectrometria de Massa de Íon Secundário/métodos , Compostos Orgânicos/análise
14.
Molecules ; 22(8)2017 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-28792469

RESUMO

A chemical investigation was conducted on the aerial parts of the mangrove plant Sonneratia paracaseolaris, yielding five new triterpenoid paracaseolins A-E (1-4, and 11) together with twelve known analogues (5-10, 12-17). Their structures were established by extensive spectroscopic methods and comparisons their spectroscopic data with those of the known related compounds. The cytotoxicities against P388, HeLa, A549, and K562 tumor cell lines and anti-H1N1 (Influenza A virus) activities for the isolates were evaluated. Compound 4 showed potent cytotoxicity against the A549 cell line with an IC50 value of 1.89 µM, and compound 1 exhibited significant anti-H1N1 virus activity with an IC50 value of 28.4 µg/mL. A preliminary structure activity relationship was discussed.


Assuntos
Antivirais/farmacologia , Embriófitas/química , Extratos Vegetais/química , Triterpenos/química , Triterpenos/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular , Descoberta de Drogas , Humanos , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade , Triterpenos/toxicidade
15.
Exp Parasitol ; 177: 13-21, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28351683

RESUMO

Absence of a drug that kills adult filarial parasites remains the major challenge in eliminating human lymphatic filariasis (LF); the second leading cause of long-term and permanent disability. Thus, the discovery of novel antifilarial natural products with potent adulticidal activity is an urgent need. In the present study, methanol extracts of leaves, bark and winged seeds of Dipterocarpus zeylanicus (Dipterocarpaceae) were investigated for macro and microfilaricidal activity. Two antifilarial triterpene saponins were isolated from winged seed extracts by bioactivity guided chromatographic separation and identified using Nuclear Magnetic Resonance and mass spectroscopic analysis as oleanolic acid 3-O-ß-D- glucopyranoside (1) (IC50 = 20.54 µM for adult worms, 19.71 µM for microfilariae ) and oleanolic acid 3-O-α-L-arabinopyranoside (2) (IC50 = 29.02 µM for adult worms, 25.99 µM for microfilariae). Acid hydrolysis of both compounds yielded oleanolic acid (3) which was non or least toxic to human peripheral blood mono nuclear cells (Selectivity index = >10) while retaining similar macrofilaricidal (IC50 = 38.4 µM) and microfilaricidal (IC50 = 35.6 µM) activities. In adult female worms treated with 50 and 100 µM doses of oleanolic acid, condensation of nuclear DNA, apoptotic body formation and tissue damage was observed by using Hoechst 33342 staining, TUNEL assay and Hematoxylin and Eosin staining respectively. A dose dependent increase in caspase 3/CED3 activity and decrease in total protein content were also observed in these parasites. A dose dependant DNA fragmentation was observed in adult parasites and microfilariae. Decreased levels of reduced glutathione (GSH) and elevated levels of glutathione S transferase (GST), superoxide dismutase (SOD) and reactive oxygen species (ROS) were also observed in parasites treated with oleanolic acid indicating an oxidative stress mediated apoptotic event. Compound 3/oleanolic acid was thus identified as a potent and safe antifilarial compound in vitro.


Assuntos
Apoptose/efeitos dos fármacos , Embriófitas/química , Ácido Oleanólico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Saponinas/química , Setaria (Nematoide)/efeitos dos fármacos , Animais , Caspase 3/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Marcação In Situ das Extremidades Cortadas , Concentração Inibidora 50 , Dose Letal Mediana , Ácido Oleanólico/isolamento & purificação , Casca de Planta/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia , Folhas de Planta/química , Espécies Reativas de Oxigênio/metabolismo , Sementes/química , Setaria (Nematoide)/citologia , Setaria (Nematoide)/metabolismo , Setaríase/tratamento farmacológico , Setaríase/parasitologia , Coloração e Rotulagem , Triterpenos/química
16.
Planta Med ; 83(9): 790-796, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28152554

RESUMO

Hymenocardine is a cyclopeptide alkaloid present in the root bark of Hymenocardia acida. In traditional African medicine, the leaves and roots of this plant are used to treat malaria, and moderate in vitro antiplasmodial activity has been reported for hymenocardine. However, in view of its peptide-like nature, potential metabolisation after oral ingestion has to be taken into account when considering in vivo experiments. In this study, the stability and small intestinal absorption of hymenocardine was assessed using an in vitro gastrointestinal dialysis model. In addition, potential liver metabolisation was investigated in vitro by incubation with a human S9 fraction. Moreover, hymenocardine was administered to rats per os, and blood and urine samples were collected until 48 and 24 h after oral administration, respectively. All samples resulting from these three experiments were analyzed by LC-MS. Analysis of the dialysate and retentate, obtained from the gastrointestinal dialysis model, indicated that hymenocardine is absorbed unchanged from the gastrointestinal tract, at least in part. After S9 metabolisation, several metabolites of hymenocardine could be identified, the major ones being formed by the reduction and/or the loss of an N-methyl group. The in vivo study confirmed that hymenocardine is absorbed from the gastrointestinal tract unchanged, since it could be identified in both rat plasma and urine, together with hymenocardinol, its reduction product.


Assuntos
Alcaloides/metabolismo , Embriófitas/química , Absorção Gastrointestinal , Peptídeos Cíclicos/metabolismo , Extratos Vegetais/metabolismo , Alcaloides/sangue , Alcaloides/química , Alcaloides/urina , Animais , Fracionamento Químico , Humanos , Fígado/metabolismo , Masculino , Medicinas Tradicionais Africanas , Estrutura Molecular , Peptídeos Cíclicos/sangue , Peptídeos Cíclicos/química , Peptídeos Cíclicos/urina , Extratos Vegetais/sangue , Extratos Vegetais/química , Extratos Vegetais/urina , Ratos , Ratos Wistar
17.
Microb Pathog ; 103: 13-18, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27988226

RESUMO

Aniba canelilla (H.B.K.) Mez, popularly known as "casca-preciosa" (precious bark), is a plant of the Lauraceae family, widely distributed in the Amazon region. Its major constituent is 1-nitro-2-phenylethane, a rare molecule in plants which is responsible for this plant's cinnamon scent. The present study aimed to report the chemical characterization of the oil extracted from Aniba canelilla using gas-chromatography/mass spectrometry and to assess its in vitro trypanocidal activity against Trypanosoma evansi, a prevalent haemoflagellate parasite that affects a broad range of mammal species in Africa, Asia and South America. The oil presented 1-nitro-2-phenylethane (83.68%) and methyleugenol (14.83%) as the two major components. The essential oil as well as both major compounds were shown to exert trypanocidal effect. Methyleugenol was slightly more active than 1-nitro-2-phenylethane. In vitro studies showed that the oil extracted from the stems of A. canelilla may be regarded as a potential natural treatment for trypanosomosis, once proven their in vivo action, may be an interesting alternative in the treatment of infected animals with T. evansi.


Assuntos
Embriófitas/química , Linfócitos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Gasosa , Humanos , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Extratos Vegetais/química , Óleos de Plantas/química , Tripanossomicidas/química
18.
Biophys Chem ; 218: 14-26, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27586818

RESUMO

Photosynthetic eukaryotes have a complex evolutionary history shaped by multiple endosymbiosis events that required a tight coordination between the organelles and the rest of the cell. Plant ionotropic glutamate receptors (iGLRs) form a large superfamily of proteins with a predicted or proven non-selective cation channel activity regulated by a broad range of amino acids. They are involved in different physiological processes such as C/N sensing, resistance against fungal infection, root and pollen tube growth and response to wounding and pathogens. Most of the present knowledge is limited to iGLRs located in plasma membranes. However, recent studies localized different iGLR isoforms to mitochondria and/or chloroplasts, suggesting the possibility that they play a specific role in bioenergetic processes. In this work, we performed a comparative analysis of GLR sequences from bacteria and various photosynthetic eukaryotes. In particular, novel types of selectivity filters of bacteria are reported adding new examples of the great diversity of the GLR superfamily. The highest variability in GLR sequences was found among the algal sequences (cryptophytes, diatoms, brown and green algae). GLRs of land plants are not closely related to the GLRs of green algae analyzed in this work. The GLR family underwent a great expansion in vascular plants. Among plant GLRs, Clade III includes sequences from Physcomitrella patens, Marchantia polymorpha and gymnosperms and can be considered the most ancient, while other clades likely emerged later. In silico analysis allowed the identification of sequences with a putative target to organelles. Sequences with a predicted localization to mitochondria and chloroplasts are randomly distributed among different type of GLRs, suggesting that no compartment-related specific function has been maintained across the species.


Assuntos
Evolução Molecular , Filogenia , Receptores Ionotrópicos de Glutamato/genética , Sequência de Aminoácidos , Animais , Clorófitas/química , Cloroplastos/química , Embriófitas/química , Mitocôndrias/química , Fotossíntese/genética , Alinhamento de Sequência
19.
Wei Sheng Yan Jiu ; 45(3): 442-7, 2016 May.
Artigo em Chinês | MEDLINE | ID: mdl-27459809

RESUMO

OBJECTIVE: To study the inhibition effect of Salvinia natans ( L. ) All. on harmful algae. METHODS: With Microcystis aeruginosa as the subjects, deionized water, ethanol, acetone, ethyl acetate as solvent, four kinds of crude extracts from Salvinia natans (L.) All. were prepared, and their alga-inhibiting actions were verified, respectively. The crude extracts of Salvinia natans (L.) All. with better inhibition effect were selected. The components of algal inhibiting material through macroporous resin purification were obtained, and determined by gas chromatography-mass spectrometry (GC-MS). RESULTS: The algicidal effect as follows: ethyl acetate extract > acetone crude extract > ethanol crude extract > water crude extract. Meanwhile, the inhibitory substances of Salvinia natans (L.) All. may be: diacetone alcohol, methyl isobutenyl ketone, 5-methyl-2-(1-methylethyl)-1-hexanol, pentadecanal, 14-heptadecenal, cumene, butyl acetate, ascorbyl dipalmitate, 1, 2-benzenedicarboxylic acid, mono (2- ethylhexyl) ester, dibutyl phthalate and phthalic acid, butyl undecane ester. CONCLUSION: The algal inhibiting effect research of Salvinia natans (L.) All., as well as its separation and identification of allelochemicals supplys theoretical basis and practical evidence not only for algae control, but also exploitation of algal inhibiting agent.


Assuntos
Embriófitas/química , Microcystis/efeitos dos fármacos , Extratos Vegetais/farmacologia , Cromatografia Gasosa-Espectrometria de Massas
20.
Indian J Pharmacol ; 48(3): 312-5, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27298503

RESUMO

OBJECTIVE: Equisetum arvense has been used to treat bone diseases. The traditional supplementation of calcium and Vitamin D for osteoporosis patients is insufficient considering the rise in patients every year. We have observed that extending the calcium and Vitamin D supplement with L-lysine, L-proline, L-arginine, and L-ascorbic acid (N) positively affects bone mineralization in ovariectomized rat. Here, we report a further extension of the above supplement with E. arvense. MATERIALS AND METHODS: The changes in serum biomarkers, bone mineral content, and femur bone histology were studied and compared to the standard drug for osteoporosis, namely raloxifene (RAL). RESULTS: We report a significant change in formation and resorption markers of bone as well as in cortical bone thickness and trabecular width in N and N + EA groups. The treatment N + EA also restored lipid profile near to normal level compared to ovariectomized group. CONCLUSIONS: Treatment N + EA was found to be as effective as RAL in reversing the osteoporotic changes.


Assuntos
Anabolizantes/uso terapêutico , Modelos Animais de Doenças , Embriófitas/química , Animais , Feminino , Ratos , Ratos Wistar
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