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1.
Antioxidants (Basel) ; 11(2)2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35204270

RESUMO

Highly productive trans-resveratrol (t-R) grapevine suspension cultured cells (SCC) and two effective elicitors, methyl jasmonate (MJ) and randomly methylated ß-cyclodextrins (CDs), were used to analyze the extent to which salt treatments alter the production of bioactive phenolic compounds. The expression/activity profile of the enzymes involved in phenol metabolism and antioxidant networks were also studied. A marked extracellular accumulation of phenolic compounds, especially t-R, was found in SCC elicited with CDs and/or MJ under saline conditions. However, the treatments with MJ alone and all those combined with salt favored the intracellular accumulation of catechin and ferulic acid. The salt-induced accumulation of phenolics was correlated with the higher total antioxidant capacity values found in cells, suggesting that cellular redox homeostasis under saline conditions was largely maintained by increasing phenolic compound production. These higher levels of phenolics found in elicited cells under saline conditions fit well with the highest activity of phenylalanine ammonia-lyase. Moreover, antioxidant enzyme activities were boosted in treatments with MJ and/or in those combined with salt and decreased in those treated with CDs. These results suggest a differential response of the antioxidative network to the presence of elicitors under saline conditions.

3.
Antioxidants (Basel) ; 9(12)2020 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-33261112

RESUMO

The agri-food industry is currently one of the main engines of economic development worldwide. The region of Murcia is a reference area in Europe for the cultivation of fruits and vegetables and produces the bulk of Spanish exports of broccoli (Brassica oleracea var. italica). The processing of fresh produce generates a huge number of by-products that represent an important economic and environmental problem when discarded. In this work, an advanced extraction technique using environmentally friendly solvents was applied to assess the revalorization of broccoli by-products, by performing a comparative analysis with conventional extraction. To achieve this goal, supercritical fluid extraction based on response surface methodology was performed using CO2 and ethanol as solvents. The results obtained showed that the supercritical fluid extracts were rich in ß-carotene, phenolic compounds, chlorophylls and phytosterols. Moreover, in bioactivity assays, the supercritical fluid extracts exhibited a high antioxidant activity and a cytoprotective effect in a non-tumorigenic keratinocyte cell line exposed to ultraviolet B light. The results indicate that supercritical fluid extracts from broccoli by-products could potentially serve as an ingredient for cosmetic purposes.

4.
Front Plant Sci ; 9: 335, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29616056

RESUMO

Plant cell cultures constitute a potentially efficient and sustainable tool for the production of high added-value bioactive compounds. However, due to the inherent restrictions in the expression of secondary metabolism, to date the yields obtained have generally been low. Plant cell culture elicitation can boost production, sometimes leading to dramatic improvements in yield, as well as providing insight into the target biosynthetic pathways and the regulation of the genes involved. Among the secondary compounds successfully being produced in biotechnological platforms are taxanes and trans-resveratrol (t-R). In the current study, perfluorodecalins (PFDs) and hexenol (Hex) were tested for the first time with Taxus media and Vitis vinifera cell cultures to explore their effect on plant cell growth and secondary metabolite production, either alone or combined with other elicitors already established as highly effective, such as methyl jasmonate (MeJa), coronatine (Coro) or randomly methylated ß-cyclodextrins (ß-CDs). The total taxane content at the peak of production in T. media cell cultures treated with PFDs together with Coro plus ß-CDs was 3.3-fold higher than in the control, whereas the t-R production in MeJa and ß-CD-treated V. vinifera cell cultures increased 552.6-fold compared to the extremely low-yielding control. Hex was ineffective as an elicitor in V. vinifera cell cultures, and in T. media cell suspensions it blocked the taxol production but induced a clear enhancement of baccatin III. Regarding biosynthetic gene expression, a strong positive relationship was observed between the transcript level of targeted genes and taxol production in the T. media cell cultures, but not with t-R production in the elicited V. vinifera cell cultures.

5.
Biotechnol Prog ; 33(6): 1662-1665, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28704889

RESUMO

In this work, suspension-cultured cells of mung beans and safflower were used in order to analyze the effect of methyl jasmonate and/or cyclodextrins, on bioactive compound production such as phytosterols and tocopherols. The results indicated that mung bean suspension-cultured cells produced higher amount of total phytosterols and tocopherols. In particular, mung bean suspension-cultured cells produced almost 220-fold higher levels of tocopherols than safflower suspension-cultured cells in the best conditions. However, while cyclodextrins were able to enhance extracellular production of phytosterols, in the case of tocopherols, they only increased their intracellular accumulation. Our results showed that mung bean cells could be used as a highly efficient system for the production of phytosterols and tocopherols which have a wide range of biological activities. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1662-1665, 2017.


Assuntos
Técnicas de Cultura de Células , Ciclodextrinas/farmacologia , Fitosteróis/biossíntese , Tocoferóis/metabolismo , Carthamus tinctorius/citologia , Carthamus tinctorius/metabolismo , Fitosteróis/química , Tocoferóis/química , Vigna/citologia , Vigna/metabolismo
6.
Plant Physiol Biochem ; 97: 361-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26529079

RESUMO

In the present work the effect of cyclodextrin and coronatine on both trans-resveratrol production and the expression of stilbene biosynthetic genes in Vitis vinifera L. cv Monastrell suspension cultured cells were evaluated. The results showed the maximum level of trans-resveratrol produced by cells and secreted to the culture medium with 50 mM cyclodextrins and 1 µM coronatine. Since the levels of trans-resveratrol produced in the combined treatment were higher than the sum of the individual treatments, a synergistic effect between both elicitors was assumed. In addition, all the analysed genes were induced by cyclodextrins and/or coronatine. The expression of the phenylalanine ammonia lyase and stilbene synthase genes was greatly enhanced by coronatine although an increase in the amount of trans-resveratrol in the spent medium was not detected. Therefore, despite the fact that trans-resveratrol production is related with the expression of genes involved in the biosynthetic process, other factors may be involved, such as post-transcriptional and post-traductional regulation. The expression maximal levels of cinnamate 4-hydroxylase and 4-coumarate-CoA ligase genes were found with cyclodextrins alone or in combination with coronatine suggesting that the activity of these enzymes could be not only important for the formation of intermediates of trans-R biosynthesis but also for those intermediates involved in the biosynthesis of lignins and/or flavonoids.


Assuntos
Aminoácidos/farmacologia , Ciclodextrinas/farmacologia , Espaço Extracelular/metabolismo , Indenos/farmacologia , Estilbenos/metabolismo , Vitis/citologia , Vitis/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Espaço Extracelular/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Espaço Intracelular/metabolismo , Resveratrol , Suspensões , Vitis/efeitos dos fármacos , Vitis/genética
7.
Plant Sci ; 239: 192-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26398803

RESUMO

Class III peroxidases are glycoproteins with a major role in cell wall maturation such as lignin formation. Peroxidases are usually present in a high number of isoenzymes, which complicates to assign specific functions to individual peroxidase isoenzymes. Arabidopsis genome encodes for 73 peroxidases, among which AtPrx72 has been shown to participate in lignification. Here, we report by using knock out peroxidase mutants how the disruption of AtPrx72 causes thinner secondary walls in interfascicular fibres but not in the xylem of the stem. This effect is also age-dependent, and AtPrx72 function seems to be particularly important when lignification prevails over elongation processes. Finally, the suppression AtPrx72 leads to the down-regulation of lignin biosynthesis pathway, as well as genes and transcription factors involved in secondary wall thickening.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Regulação da Expressão Gênica de Plantas , Lignina/genética , Peroxidases/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Parede Celular/metabolismo , Técnicas de Inativação de Genes , Lignina/biossíntese , Peroxidases/metabolismo , Caules de Planta/genética , Caules de Planta/metabolismo , Metabolismo Secundário
8.
Physiol Plant ; 154(3): 395-406, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25410139

RESUMO

Lignins result from the oxidative polymerization of three hydroxycinnamyl (p-coumaryl, coniferyl and sinapyl) alcohols in a reaction mediated by peroxidases (EC 1.11.1.7) and laccases (EC 1.10.3.2), yielding H, G and S units, respectively. Although both acidic and basic peroxidases can oxidize p-coumaryl and coniferyl alcohol, only basic peroxidases are able to oxidize sinapyl alcohol. The AtPrx52 from Arabidopsis is a basic peroxidase that has been reported to be highly homologous to the basic peroxidase of Zinnia elegans, the only peroxidase which has been unequivocally linked to lignin formation. Here, we show how the suppression of AtPrx52 causes a change in lignin composition, mainly at the level of stem interfascicular fibers. Quantification of lignins in two different atprx52 knock-out mutants revealed a decrease of lignin amount compared with wild type. The S/G ratio, obtained by both nitrobenzene oxidation and thioacidolysis, indicated a decrease in S units in the atprx52 mutants. As deduced from Wiesner and mainly Mäule staining, this reduction in S unit content appears to be restricted to the interfascicular fibers. Moreover, quantitative polymerase chain reaction analysis in atprx52 plants showed a general downregulation of genes involved in lignin biosynthetic pathway, as well as genes related to secondary cell wall. On the other hand, other routes from phenylpropanoid metabolism were induced. Taken together, our results indicate that AtPrx52 is involved in the synthesis of S units in interfascicular fibers at late stages of the lignification process.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Lignina/metabolismo , Peroxidases/metabolismo , Caules de Planta/metabolismo , Xilema/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Parede Celular/genética , Parede Celular/metabolismo , Perfilação da Expressão Gênica , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Técnicas de Inativação de Genes , Lignina/ultraestrutura , Microscopia Eletrônica de Transmissão , Mutação , Peroxidases/genética , Caules de Planta/genética , Caules de Planta/ultraestrutura , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Xilema/genética
9.
J Plant Physiol ; 175: 86-94, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25506770

RESUMO

Syringyl lignins result from the oxidative polymerization of sinapyl alcohol in a reaction mediated by syringyl (basic) peroxidases. Several peroxidases have been identified in the genome of Arabidopsis thaliana as close homologues to ZePrx, the best characterized basic peroxidase so far, but none of these has been directly involved in lignification. We have used a knock-out mutant of AtPrx4, the closest homologue to ZePrx, to study the involvement of this basic peroxidase in the physiology of the plant under both long- and short-day light conditions. Our results suggest that AtPrx4 is involved in cell wall lignification, especially in syringyl monomer formation. The disruption of AtPrx4 causes a decrease in syringyl units proportion, but only when light conditions are optimal. Moreover, the effect of AtPrx4 disruption is age-dependent, and it is only significant when the elongation process of the stem has ceased and lignification becomes active. In conclusion, AtPrx4 emerges as a basic peroxidase regulated by day length with an important role in lignification.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Regulação da Expressão Gênica de Plantas , Lignina/metabolismo , Peroxidase/metabolismo , Peroxidases/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Parede Celular/metabolismo , Oxirredução , Peroxidase/genética , Peroxidases/genética , Caules de Planta/enzimologia , Caules de Planta/genética
10.
PLoS One ; 9(10): e109777, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25314001

RESUMO

The high effectiveness of cyclic oligosaccharides like cyclodextrins in the production of trans-resveratrol in Vitis vinifera cell cultures is enhanced in the presence of methyl jasmonate. In order to dissect the basis of the interactions among the elicitation responses triggered by these two compounds, a transcriptional analysis of grapevine cell cultures treated with cyclodextrins and methyl jasmonate separately or in combination was carried out. The results showed that the activation of genes encoding enzymes from phenylpropanoid and stilbene biosynthesis induced by cyclodextrins alone was partially enhanced in the presence of methyl jasmonate, which correlated with their effects on trans-resveratrol production. In addition, protein translation and cell cycle regulation were more highly repressed in cells treated with cyclodextrins than in those treated with methyl jasmonate, and this response was enhanced in the combined treatment. Ethylene signalling was activated by all treatments, while jasmonate signalling and salicylic acid conjugation were activated only in the presence of methyl jasmonate and cyclodextrins, respectively. Moreover, the combined treatment resulted in a crosstalk between the signalling cascades activated by cyclodextrins and methyl jasmonate, which, in turn, provoked the activation of additional regulatory pathways involving the up-regulation of MYB15, NAC and WRKY transcription factors, protein kinases and calcium signal transducers. All these results suggest that both elicitors cause an activation of the secondary metabolism in detriment of basic cell processes like the primary metabolism or cell division. Crosstalk between cyclodextrins and methyl jasmonate-induced signalling provokes an intensification of these responses resulting in a greater trans-resveratrol production.


Assuntos
Acetatos/farmacologia , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Vitis/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resveratrol , Estilbenos/metabolismo , Transcriptoma , Regulação para Cima , Vitis/efeitos dos fármacos , Vitis/genética
11.
Plant Biotechnol J ; 12(8): 1075-84, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24909837

RESUMO

Methyl jasmonate and cyclodextrins are proven effective inducers of secondary metabolism in plant cell cultures. Cyclodextrins, which are cyclic oligosaccharides, can form inclusion complexes with nonhydrophilic secondary products, thus increasing their excretion from the producer cells to the culture medium. In the present work, using a selected Taxus x media cell line cultured in a two-stage system, the relationship between taxane production and the transcript profiles of several genes involved in taxol metabolism was studied to gain more insight into the mechanism by which these two elicitors regulate the biosynthesis and excretion of taxol and related taxanes. Gene expression was not clearly enhanced by the presence of cyclodextrins in the culture medium and variably induced by methyl jasmonate, but when the culture was supplemented with both elicitors, a synergistic effect on transcript accumulation was observed. The BAPT and DBTNBT genes, which encode the last two transferases involved in the taxol pathway, appeared to control limiting biosynthetic steps. In the cell cultures treated with both elicitors, the produced taxanes were found mainly in the culture medium, which limited retroinhibition processes and taxane toxicity for the producer cells. The expression level of a putative ABC gene was found to have increased, suggesting it played a role in the taxane excretion. Taxol biosynthesis was clearly increased by the joint action of methyl jasmonate and cyclodextrins, reaching production levels 55 times higher than in nonelicited cultures.


Assuntos
Acetatos/farmacologia , Hidrocarbonetos Aromáticos com Pontes/metabolismo , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Regulação da Expressão Gênica de Plantas , Oxilipinas/farmacologia , Taxoides/metabolismo , Taxus/efeitos dos fármacos , Vias Biossintéticas , Hidrocarbonetos Aromáticos com Pontes/química , Células Cultivadas , Sinergismo Farmacológico , Proteínas de Plantas/genética , Taxoides/química , Taxus/química
12.
Plant Physiol Biochem ; 77: 133-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24589476

RESUMO

Suspension cultured-cells (SCC) of Daucus carota were used to evaluate the effect of methyl jasmonate and cyclodextrins, separately or in combination, on the induction of defense responses, particularly the accumulation of pathogenesis-related proteins. A comparative study of the extracellular proteome (secretome) between control and elicited carrot SCC pointed to the presence of amino acid sequences homologous to glycoproteins which have inhibitory activity against the cell-wall-degrading enzymes secreted by pathogens and/or are induced when carrot cells are exposed to a pathogen elicitor. Other amino acid sequences were homologous to Leucine-Rich Repeat domain-containing proteins, which play an essential role in defense against pathogens, as well as in the recognition of microorganisms, making them important players in the innate immunity of this plant. Also, some tryptic peptides were shown to be homologous to a thaumatin-like protein, showing high specificity to abiotic stress and to different reticuline oxidase-like proteins that displayed high levels of antifungal activity, suggesting that methyl jasmonate and cyclodextrins could play a role in mediating defense-related gene product expression in SCC of D. carota. Apart from these elicitor-inducible proteins, we observed the presence of PR-proteins in both control and elicited carrot SCC, suggesting that their expression is mainly constitutive. These PR-proteins are putative class IV chitinases, which also have inhibitory activity against pathogen growth and the class III peroxidases that participate in response to environmental stress (e.g. pathogen attack and oxidative), meaning that they are involved in defense responses triggered by both biotic and abiotic factors.


Assuntos
Acetatos/farmacologia , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Daucus carota/efeitos dos fármacos , Oxilipinas/farmacologia , Doenças das Plantas , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/metabolismo , Estresse Fisiológico , Células Cultivadas , Quitinases/metabolismo , Daucus carota/metabolismo , Peroxidases/metabolismo
13.
Proc Natl Acad Sci U S A ; 111(4): 1634-9, 2014 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-24434554

RESUMO

The saikosaponins comprise oleanane- and ursane-type triterpene saponins that are abundantly present in the roots of the genus Bupleurum widely used in Asian traditional medicine. Here we identified a gene, designated CYP716Y1, encoding a cytochrome P450 monooxygenase from Bupleurum falcatum that catalyzes the C-16α hydroxylation of oleanane- and ursane-type triterpenes. Exploiting this hitherto unavailable enzymatic activity, we launched a combinatorial synthetic biology program in which we combined CYP716Y1 with oxidosqualene cyclase, P450, and glycosyltransferase genes available from other plant species and reconstituted the synthesis of monoglycosylated saponins in yeast. Additionally, we established a culturing strategy in which applying methylated ß-cyclodextrin to the culture medium allows the sequestration of heterologous nonvolatile hydrophobic terpenes, such as triterpene sapogenins, from engineered yeast cells into the growth medium, thereby greatly enhancing productivity. Together, our findings provide a sound base for the development of a synthetic biology platform for the production of bioactive triterpene sapo(ge)nins.


Assuntos
Bupleurum/enzimologia , Técnicas de Química Combinatória , Saccharomyces cerevisiae/metabolismo , Sapogeninas/metabolismo , Saponinas/biossíntese , Esteroide 16-alfa-Hidroxilase/genética , Meios de Cultura , Hidroxilação , Dados de Sequência Molecular , RNA Mensageiro/genética
14.
Methods Mol Biol ; 1072: 155-69, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24136521

RESUMO

Protein relative quantitation is one of the main targets in many proteomic experiments. Among the range of techniques available for both top-down and bottom-up approaches, isobaric tags for relative and absolute quantitation (iTRAQ) have gained positions within the top-rank techniques used for this purpose in the recent years. Briefly, each iTRAQ reagent consists of three different components: a reporter group (with a variable mass in the range of 114-117 amu), a balance group, and an amino-reactive group. The isobaric nature of iTRAQ-labeled peptides adds a signal to every peptide in the sample which is detectable in both MS and MS/MS spectra, thus enhancing the sensitivity of detection. During MS/MS, the reporter groups are released as singly charged ions with m/z ratios ranking from 114 to 117 amu, visible in the low mass region of MS/MS spectra. The iTRAQ technology can be used to analyze up to four different samples using the 4-plex kit (reporter groups 114-115 amu) or can be scaled up to eight different samples using the 8-plex kit (reporter groups 113-121 amu). In this chapter, we focus on the experimental procedures typically using 4-plex labeling, including tips leading to successful application of iTRAQ technology for the analysis of plant protein mixtures.


Assuntos
Marcação por Isótopo/métodos , Proteínas de Plantas/metabolismo , Proteoma/metabolismo , Vitis/metabolismo , Fracionamento Químico , Espectrometria de Massas , Estatística como Assunto
15.
Methods Mol Biol ; 1072: 407-33, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24136538

RESUMO

Suspension-cultured cells (SCC) are generally considered the most suitable cell systems to carry out scientific studies, including the extracellular proteome (secretome). SCC are initiated by transferring friable callus fragments into flasks containing liquid culture medium for cell biomass growth, and they are maintained in an orbital shaker to supply the sufficient oxygen that allows cell growth. SCC increase rapidly during the exponential phase and after 10-20 days (depending on the cell culture nature), the growth rate starts to decrease due to limitation of nutrients, and to maintain for decades these kinds of cell cultures is needed to transfer a portion of these SCC into a fresh culture medium. Despite the central role played by extracellular proteins in most processes that control growth and development, the secretome has been less well characterized than other subcellular compartments, meaning that our understanding of the cell wall physiology is still very limited. Useful proteomic tools have emerged in recent years to unravel metabolic network that occurs in cell walls. With the recent progress made in mass spectrometry technology, it has become feasible to identify proteins from a given organ, tissue, cells, or even a subcellular compartment. Compared with other methods used to isolate cell wall proteins, the spent medium of SCC provides a convenient, continuous, and reliable and unique source of extracellular proteins. Therefore, this biological system could be used as a large-scale cell culture from which these proteins can be secreted, easily separated from cells without cell disruption, and so, without any cytosolic contamination, easily recovered from the extracellular medium. This nondestructive cell wall proteome approach discloses a set of proteins that are specifically expressed in the remodelling of the cell wall architecture and stress defense.


Assuntos
Espaço Extracelular/metabolismo , Células Vegetais/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Vitis/citologia , Vitis/metabolismo , Células Cultivadas , Cromatografia Líquida , Bases de Dados de Proteínas , Eletroforese em Gel Bidimensional , Focalização Isoelétrica , Espectrometria de Massas , Análise de Sequência de Proteína , Software , Coloração e Rotulagem , Suspensões
16.
Pharm Biol ; 51(3): 304-10, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23137274

RESUMO

CONTEXT: Catharanthus roseus (L.) G. Don (Apocynaceae) is a medicinal plant that produces more than 130 alkaloids, with special attention given to the production of the anti-hypertensive monomeric indole alkaloids, serpentine and ajmalicine, and the antitumor dimeric alkaloids, vinblastine and vincristine. OBJECTIVE: This study evaluated the cytotoxic activity of the indole alkaloid-enriched bioactive extract obtained from suspension cultured-cells of C. roseus elicited with methyl jasmonate (MJ) and cyclodextrins (CDs) in three cell lines: JURKAT E.6 human lymphocytic leukemia, THP-1 human monocytic leukemia and BL 1395 non-tumor human B-cell line. MATERIALS AND METHODS: An indole alkaloid-enriched bioactive extract was obtained from C. roseus cell cultures elicited with MJ and CDs. The indole alkaloids were identified using an HPLC-diode array system coupled to a time-of-flight mass spectrometer using electrospray ionization (ESI) source. The cytotoxic assays were made using the colorimetric assay 2, 3-bis (2-methoxy-4-nitro-5-sulfophenyl)-S-[(phenylamino)carbonyl]-2 tetrazolium hydroxide (XTT). RESULTS: Four indole alkaloids were identified (catharanthine, ajmalicine, tabersonine and lochnericine) but only catharanthine and ajmalicine were quantified. The concentration of the indole alkaloid-enriched bioactive extract that inhibited cell growth by 50% was 211 and 210 ng/mL for the JURKAT E.6 and THP-1 cell lines, respectively. DISCUSSION AND CONCLUSION: The results confirm that the powerful antitumor activity of this indole alkaloid-enriched bioactive extract is not due to the effect of a single compound but depends on the synergistic action of the four compounds identified.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Catharanthus/metabolismo , Alcaloides Indólicos/farmacologia , Extratos Vegetais/farmacologia , Folhas de Planta/metabolismo , Acetatos/farmacologia , Antineoplásicos Fitogênicos/biossíntese , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Catharanthus/química , Catharanthus/citologia , Catharanthus/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Descoberta de Drogas , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/metabolismo , Concentração Inibidora 50 , Oxilipinas/farmacologia , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Folhas de Planta/citologia , Folhas de Planta/efeitos dos fármacos , Quinolinas/química , Quinolinas/metabolismo , Quinolinas/farmacologia , Alcaloides de Triptamina e Secologanina/química , Alcaloides de Triptamina e Secologanina/metabolismo , Alcaloides de Triptamina e Secologanina/farmacologia , Espectrometria de Massas por Ionização por Electrospray , Alcaloides de Vinca/química , Alcaloides de Vinca/metabolismo , Alcaloides de Vinca/farmacologia
17.
Plant Physiol Biochem ; 62: 107-10, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23208304

RESUMO

The use of cyclic oligosaccharides like cyclodextrins (CDs), alone or combined with methyl jasmonate (MJ), as elicitors has proved very effective in stimulating the production of trans-resveratrol (trans-R) in Vitis vinifera suspension-cultured cells (SCC). Since elicitors can be used to increase trans-R production, understanding the molecular mechanisms involved would improve the management of grapevine cells as factories of this compound. The results obtained in this study provide evidence for a role of Ca(2+) in mediating elicitor-induced trans-R production in grapevine SCC. The Ca(2+) elevation was promoted by an uptake of Ca(2+) from the extracellular medium, and by Ca(2+) mobilization from intracellular organelles. Moreover, protein phosphorylation/dephosphorylation events seem to be involved in the signal transduction pathways triggered by CDs separately or in combination with MJ since trans-R production is dependent on both, the phosphorylation status of several proteins through mitogen-activated kinase pathway and the activity of tyrosine phosphatases. Our results also suggest that H(2)O(2) and NO participated in the production of trans-R triggered by both elicitors in grapevine SCC. Finally, a fast alkalinization of the extracellular medium is induced in the presence of CDs and/or MJ.


Assuntos
Acetatos/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oxilipinas/farmacologia , Células Vegetais/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Vitis/metabolismo , Sinalização do Cálcio/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Peróxido de Hidrogênio/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Óxido Nítrico/metabolismo , Proteínas de Plantas/metabolismo , Vitis/citologia
18.
Plant Foods Hum Nutr ; 67(4): 422-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23161277

RESUMO

trans-Resveratrol (trans-R) has been reported to be a potential cancer chemopreventive agent. Although its cytotoxic activity against different cancer cell lines has been tested, its effect on human acute leukemia cell lines has scarcely been investigated, and only a few in vitro studies were performed using human breast epithelial cell lines. Due to its potential value for human health, demand for trans-R has rapidly increased, and new biotechnological strategies to obtain it from natural edible sources have been developed. Thus, grapevine cell cultures represent a reliable system of trans-R production since they biosynthesize trans-R constitutively or in response to elicitation. In addition, there are no studies deepen on the inhibitory effect of trans-R, produced by elicited grapevine cell cultures, on growth of human tumor cell lines. In this work, the effect of trans-R extracted from the culture medium, after elicitation of grapevine cell cultures, was tested on two human acute lymphocytic and monocytic leukemia cell lines, and one human breast cancer cell line. The effect of trans-R on cell proliferation was not only dose- and time-dependent but also cell type-dependent, as seen from the different degrees of susceptibility of cancer cell lines tested. As regards the effect of trans-R on cell cycle distribution, low trans-R concentrations increased cells in the S phase whereas a high trans-R concentration increased G0/G1 phase in all cell lines. Perturbation of the cell cycle at low trans-R concentrations did not correlate with the induction of cell death, whereas a high trans-R concentration, cell proliferation decreased as a result of increasing apoptosis in the three cell lines. In leukemia cells, trans-R up-regulated the expression of caspase-3 while trans-R-induced apoptosis in breast cells occur through a caspase-3-independent mechanism mediated by a down-regulation of Bcl-2.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Estilbenos/farmacologia , Vitis/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Ciclodextrinas/farmacologia , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Feminino , Genes bcl-2/efeitos dos fármacos , Humanos , Resveratrol , Espectrometria de Massas por Ionização por Electrospray , Estilbenos/isolamento & purificação , Fatores de Tempo , Regulação para Cima/efeitos dos fármacos , Vitis/efeitos dos fármacos
19.
Plant Physiol Biochem ; 51: 1-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22153233

RESUMO

We analyze, for the first time, the early signal transduction pathways triggered by methyl jasmonate (MJ) and cyclodextrins (CDs) in tobacco (Nicotiana tabacum) cell cultures, paying particular attention to changes in cytosolic free Ca(2+) concentration ([Ca(2+)](cyt)), the production of hydrogen peroxide (H(2)O(2)) and nitric oxide (NO), and late events like the induction of capsidiol. Our data indicate that MJ and CDs trigger a [Ca(2+)](cyt) rise promoted by Ca(2+) influx through Ca(2+)-permeable channels. The joint presence of MJ and CDs provokes a first increase in [Ca(2+)](cyt) similar to that observed in MJ-treated cells, followed by a second peak similar to that found in the presence of CDs alone. Moreover, oxidative burst induced by MJ is more pronounced when tobacco cells are incubated with CDs alone or in combination with MJ. The presence of both elicitors provokes H(2)O(2) production similar to that found in CD-treated cells, and a sustained response similar to that found in MJ-treated cells. In all treatments, H(2)O(2) production is dependent on Ca(2+) influx and protein phosphorylation events. Similarly, the joint action of both elicitors provokes NO accumulation, although to a lesser extent that in MJ-treated cells because CDs alone do not trigger this accumulation. This NO production is dependent on Ca(2+) influx but independent of both H(2)O(2) production and staurosporine-sensitive phosphorylation events. Taken as a whole, these results suggest the existence of different intracellular signaling pathways for both elicitors. Likewise, CDs might act by regulating the signaling pathway triggered by MJ since, in the presence of both compounds, CDs neutralize the strong oxidative and nitrosative bursts triggered by MJ and therefore, they regulate both H(2)O(2) and NO levels.


Assuntos
Acetatos/farmacologia , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Nicotiana/efeitos dos fármacos , Oxilipinas/farmacologia , Células Vegetais/metabolismo , Transdução de Sinais , Cálcio/metabolismo , Células Cultivadas , Meios de Cultura/metabolismo , Citosol/metabolismo , Peróxido de Hidrogênio/metabolismo , Estrutura Molecular , Óxido Nítrico/metabolismo , Oniocompostos/farmacologia , Fosforilação , Células Vegetais/efeitos dos fármacos , Explosão Respiratória , Sesquiterpenos/metabolismo , Nicotiana/citologia , Nicotiana/metabolismo
20.
Plant Cell Rep ; 31(1): 81-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21927985

RESUMO

In this work, the effect of different inducing factors on trans-resveratrol extracellular production in Monastrell grapevine suspension cultured cells is evaluated. A detailed analysis provides the optimal concentrations of cyclodextrins, methyljasmonate and UV irradiation dosage, optimal cell density, elicitation time and sucrose content in the culture media. The results indicate that trans-resveratrol production decreases as the initial cell density increases for a constant elicitor concentration in Monastrell suspension cultured cells treated with cyclodextrins individually or in combination with methyljasmonate; the decrease observed in cell cultures elicited with cyclodextrins alone is far more drastic than those observed in the combined treatment. trans-Resveratrol extracellular production observed by the joint use of cyclodextrins and methyljasmonate (1,447.8 ± 60.4 µmol trans-resveratrol g(-1) dry weight) is lower when these chemical compounds are combined with UV light short exposure (669.9 ± 45.2 µmol trans-resveratrol g(-1) dry weight). Likewise, trans-resveratrol production is dependent on levels of sucrose in the elicitation medium with the maximal levels observed with 20 g l(-1) sucrose and the joint action of cyclodextrins and 100 µM methyljasmonate. The sucrose concentration did not seem to limit the process although it affects significantly the specific productivity since the lowest sucrose concentration is 10 g l(-1), the highest productivity is reached (100.7 ± 5.8 µmol trans-resveratrol g(-1) dry weight g(-1) sucrose) using cyclodextrins and 25 µM methyljasmonate.


Assuntos
Acetatos/farmacologia , Técnicas de Cultura de Células/métodos , Ciclodextrinas/farmacologia , Ciclopentanos/farmacologia , Oxilipinas/farmacologia , Estilbenos/metabolismo , Vitis/citologia , Vitis/metabolismo , Biotecnologia/métodos , Células Cultivadas , Meios de Cultura/química , Meios de Cultura/farmacologia , Relação Dose-Resposta a Droga , Espaço Extracelular/metabolismo , Resveratrol , Sacarose/farmacologia , Raios Ultravioleta , Vitis/efeitos dos fármacos , Vitis/efeitos da radiação
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