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1.
Nutr Cancer ; 69(1): 117-130, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27892697

RESUMO

Use of plant extracts, alone or combined to the current chemotherapy as chemosensitizers, has emerged as a promising strategy to overcome tumor drug resistance. Here, we investigated the anticancer activity of Allium roseum L. extracts, a wild edible species in North Africa, on human Chronic Myeloid Leukemia (CML) K562 cells. The dehydrated aqueous extract (DAE) disturbed the cell cycle progression and induced the apoptosis of K562 cells. Chemical analysis of DAE showed a diversity of organosulfur compounds S-alk(en)yl-cysteine sulfoxides (RCSO) and high amount of allicin, suggesting that such molecule may be behind its antitumor effect. DAE was efficient in inhibiting K562 cell viability. DAE inhibitory effect was associated with the dephosphorylation of the BCR-ABL kinase and interfered with ERK1/2, Akt, and STAT5 pathways. Furthermore, we found that DAE-induced inactivation of Akt kinase led to the activation of its target FOXO3 transcription factor, enhancing the expression of FOXO3-regulated proapoptotic effectors, Bim and Bax, and cell cycle inhibitor p27. Finally, we found that DAE reduced the secretion of vascular endothelial growth factor. Overall, our data suggest that A. roseum extract has great potential as a nontoxic cheap and effective alternative to conventional chemotherapy.


Assuntos
Allium/química , Antineoplásicos Fitogênicos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Proteínas de Fusão bcr-abl/antagonistas & inibidores , Proteínas de Fusão bcr-abl/metabolismo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT5/metabolismo
2.
Pest Manag Sci ; 75(5): 1252-1257, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30324644

RESUMO

BACKGROUND: Plasmopara viticola control in organic viticulture requires copper-based fungicides with harmful effects on health and the environment. Plant extracts represent a biorational eco-friendly alternative to copper. The aim of this study was to evaluate the potential of stilbenoid-rich grape cane extract (GCE) against downy mildew on three cultivars over 3 years following natural downy mildew infection. RESULTS: Over all field trials, GCE treatments showed an average reduction in disease incidence of -35% and -38% on leaves and clusters, respectively. The average reduction in disease severity was -35% and -43% on leaves and clusters, respectively. Under artificial downy mildew infection, GCE efficacy corresponded to 1 g L-1 of copper. Neither phytotoxicity nor adverse effects on auxiliary fauna were observed after treatment with GCE. CONCLUSION: Because few or no biocontrol agents are active alone against P. viticola, GCE is a promising alternative to copper-based fungicides. Grape canes, an abundant by-product of viticulture, have great potential for valorization as a biocontrol agent for sustainable viticulture. © 2018 Society of Chemical Industry.


Assuntos
Oomicetos/fisiologia , Doenças das Plantas/microbiologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Estilbenos/química , Vitis/química , Vitis/microbiologia , Oomicetos/efeitos dos fármacos
3.
J Chromatogr A ; 1112(1-2): 23-30, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16480995

RESUMO

Garlic (Allium sativum) and onion (Allium cepa) are widely known for their biological properties but are far from having revealed all of their secrets even if the compounds involved in the biological mechanisms, flavenols, sulphur and seleno compounds have been identified. The beneficial effect of garlic on health including protection against cardiovascular diseases and cancers results from all of these compounds although their individual involvement is complex. Garlic and onion, broccoli, wild leek, have the ability to accumulate the selenium (Se) from soil. These Se-enriched plants present a greater protection against carcinogenesis than the common plants and two Se-compounds possessing anti-cancer activity have been identified: Se-methyl selenocysteine and gamma-glutamyl-Se-methyl selenocysteine. However, several Se-compounds from Se-enriched garlic or onion remain unidentified. The techniques for the detection of Se-species are numerous but few methods are able to identify the detected compounds. The very small quantities of Se-compounds present and the clear lack of standards do not make their analysis straightforward, particularly for non-enriched samples. Over the last 10 or so years development of the synthesis of Se-compounds and the use of GC-AED or EC/HPLC-ICP-MS have shown considerable possibilities. These techniques have allowed advances in the identification of Se-compounds, some of which are analogues of S-compounds in plants and yeasts. When these techniques are coupled to EC/HPLC-APCI-MS-MS, they provide a lot of information about the Se-biosynthesis in garlic. This has allowed the preferential formation of methylated compounds in Se-biochemistry to be identified, in contrast to the sulphur biochemistry of the Allium spp. in which compounds containing propenylic groups predominate. This review focuses on the recent advances in the analytical methods of Se-compounds in garlic and onion and particular attention is given to the biological properties of Se-species identified in Se-enriched plants.


Assuntos
Alho/química , Cebolas/química , Compostos de Selênio/isolamento & purificação , Animais , Fracionamento Químico , Alho/metabolismo , Humanos , Cebolas/metabolismo , Selênio/metabolismo , Compostos de Selênio/farmacologia
4.
Pest Manag Sci ; 72(10): 1901-9, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26757395

RESUMO

BACKGROUND: The effects of foliar applications of microdoses of sucrose to reduce the damage by the codling moth have been reported from nine trials carried in France and Algeria from 2009 to 2014. The activity of sucrose alone was assessed by comparison with an untreated control and some treatments with the Cydia pomonella granulovirus or a chemical insecticide. The addition of sucrose to these different treatments was also investigated. RESULTS: The application of sucrose at 0.01% reduced the means of infested fruits with a value of Abbott's efficacy of 41.0 ± 10.0%. This involved the induction of resistance by antixenosis to insect egg laying. Indeed, it seems that acceptance of egg laying on leaves treated with sucrose was reduced. The addition of sucrose to thiacloprid improved its efficacy (59.5% ± 12.8) by 18.4%. However, the sucrose had no added value when associated with C. pomonella granulovirus treatments. CONCLUSION: Foliar applications of microdoses of sucrose every 20 days in commercial orchards can partially protect against the codling moth. Its addition to thiacloprid increases the efficacy in integrated control strategies, contrary to C. pomonella granulovirus treatments. This work opens a route for the development of new biocontrol strategies. © 2016 Society of Chemical Industry.


Assuntos
Malus , Mariposas , Sacarose , Argélia , Animais , Granulovirus , Controle de Insetos/métodos , Inseticidas , Mariposas/fisiologia , Neonicotinoides , Oviposição , Controle Biológico de Vetores , Piridinas , Tiazinas
5.
Atherosclerosis ; 177(2): 291-7, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15530902

RESUMO

Numerous animal studies have reported that garlic can protect against atherosclerosis. However, a comparable number of studies do not support this observation. This contradiction may result from differences in study design, use of different animal models, and use of different garlic formulations and preparations. Here, we investigated the effect of the chemically well-characterized and production-controlled garlic powder printanor on atherosclerosis in the APOE*3-Leiden transgenic mouse, a mouse model well suited for evaluating anti-atherosclerotic properties of drugs and food components under human-like conditions. APOE*3-Leiden mice were fed a Western diet supplemented with either 5 or 50 g kg(-1) printanor. As a reference, the commercially available fermented garlic kyolic was included (1.6 g kg(-1) diet). Treatment with printanor demonstrated reduced body weight, coinciding with increased feces production and fecal fatty acids excretion. Printanor and kyolic treatment did not affect plasma lipids, markers of inflammation (serum amyloid A, serum-soluble intercellular adhesion molecule-1, and blood-leukocytes tumor necrosis factor-alpha (TNFalpha) production) and vascular activation (plasma von Willebrand factor (vWF)). As analyzed after 28 weeks of treatment, printanor and kyolic did not affect atherosclerotic lesion type, area or composition. Under conditions relevant to the human situation, the well-characterized and production-controlled garlic powder printanor does not display hypolipidemic, anti-inflammatory or anti-atherosclerotic properties.


Assuntos
Apolipoproteínas E/genética , Arteriosclerose/prevenção & controle , Alho , Animais , Apolipoproteína E3 , Modelos Animais de Doenças , Feminino , Molécula 1 de Adesão Intercelular/sangue , Lipídeos/sangue , Camundongos , Camundongos Transgênicos , Proteína Amiloide A Sérica/análise , Fator de Necrose Tumoral alfa/análise , Fator de von Willebrand/análise
6.
J Agric Food Chem ; 51(26): 7617-23, 2003 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-14664517

RESUMO

The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic consumption slightly increased ethoxyresorufin O-deethylase and CYP 1A2 levels. In contrast, garlic consumption decreased CYP 2E1 activity and the level of the corresponding isoform. UDP glucuronosyl transferase and glutathion S-transferase activities were increased by garlic powders. The alliin content of the garlic powders was positively correlated with UGT activity although not with other activities. Effects produced by garlic consumption were qualitatively similar to that of diallyl disulfide, a sulfur compound that has been extensively studied. These data could partially explain the chemoprotective effect of garlic.


Assuntos
Cisteína/análogos & derivados , Cisteína/análise , Dieta , Alho/química , Fígado/enzimologia , Animais , Anticarcinógenos , Cisteína/farmacologia , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Citocromo P-450 CYP2E1/metabolismo , Glucuronosiltransferase/metabolismo , Glutationa Transferase/metabolismo , Masculino , Ratos , Ratos Wistar
7.
Carcinogenesis ; 25(10): 1953-9, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15180943

RESUMO

Garlic (Allium sativum) is well known for its beneficial effects on health and particularly for its chemopreventive potential against cancer. The present study was designed to compare the chemopreventive efficacies of several garlic powders with various levels of alliin, a precursor of active sulfur compounds. For this purpose we used the medium-term hepatocarcinogenesis protocol (resistant hepatocyte model), which allows the detection of preneoplasic foci expressing the placental form of glutathione S-transferase (GST-P) as an end-point. Rats were fed diets containing three garlic powders (5% of the diet) with various alliin contents for 3 weeks. Garlic powders were obtained from bulbs grown on soils with different levels of sulfur fertilization. During the period of garlic feeding hepatocarcinogenesis was initiated by administration of 10 i.p. injections of 0.025 mg/kg body weight aflatoxin B1 (AFB1). The rats were later submitted to 2-acetylaminofluorene treatment and partial hepatectomy, and GST-P foci were detected and quantified. Consumption of diets containing garlic powders decreased the appearance and size of hepatic GST-P foci. A strong reduction was observed in rats fed garlic containing the highest level of alliin. In addition, increased alliin content of the garlic powder was associated with a proportional decrease in the number and area of preneoplastic foci. Elsewhere, garlic powder ingestion increased hepatic ethoxyresorufin deethylase, glutathione S-transferase and UDP glucuronosyl transferase activities while no modification of nifedipine oxidase activity was found. We also observed an increase in the levels of GST A5 and AFB1 aldehyde reductase. It is suggested that garlic partly exerts its anticarcinogenic effects through increasing enzymes involved in AFB1 detoxification. This study highlights the possibility of controlling the cultivation conditions to improve the chemopreventive efficacy of garlic.


Assuntos
Aflatoxina B1/toxicidade , Antineoplásicos/administração & dosagem , Cisteína/análogos & derivados , Cisteína/administração & dosagem , Alho , Neoplasias Hepáticas Experimentais/prevenção & controle , Animais , Quimioprevenção , Citocromo P-450 CYP1A1/metabolismo , Dieta , Glucuronosiltransferase/metabolismo , Glutationa Transferase/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Neoplasias Hepáticas Experimentais/enzimologia , Masculino , Pós , Lesões Pré-Cancerosas/induzido quimicamente , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/prevenção & controle , Ratos , Ratos Wistar
8.
J Nutr ; 134(6): 1500-3, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15173418

RESUMO

Garlic is reported to have beneficial effects on risk factors associated with cardiovascular disease, including normalization of plasma lipid levels. However, numerous studies do not support this beneficial effect of garlic on plasma lipids. This contradiction may result from the use of different garlic-derived materials, experimental designs, and/or animal models. The present study investigated the hypolipidemic effect of garlic-derived materials in APOE*3-Leiden mice, a model well suited for drug and dietary intervention studies of hyperlipidemia. APOE*3-Leiden mice were fed a garlic-derived sulfur-rich compound, either allicin (0.29 g.L drinking water(-1)) or diallyldisulfide (0.27 g.kg diet(-1)), or powdered garlic, of either the kwai (42 g.kg diet(-1)) or morado (42 g.kg diet(-1)) variety. The amounts of garlic-derived materials supplied allowed free intake of allicin or allicin equivalents (diallyldisulfide, kwai, or morado) at 44 mg.kg body wt(-1).d(-1). Mice were fed a nonpurified diet for 4 wk, followed by a Western diet for 8 wk, both supplemented with the garlic-derived materials. These diets had no consistent effect on plasma lipids and did not affect lipoprotein profiles, which are markers for whole-body cholesterol synthesis and intestinal sterol absorption. The current data indicate that the postulated effects of garlic on cardiovascular disease are not caused via modulation of plasma lipid levels.


Assuntos
Compostos Alílicos/farmacologia , Apolipoproteínas E/metabolismo , Dissulfetos/farmacologia , Alho/química , Lipídeos/sangue , Ácidos Sulfínicos/farmacologia , Animais , Apolipoproteína E3 , Apolipoproteínas E/genética , Biomarcadores/análise , Colesterol/biossíntese , Feminino , Absorção Intestinal , Lipoproteínas/sangue , Camundongos , Camundongos Transgênicos/genética , Esteróis/farmacocinética
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