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1.
Br J Nutr ; 115(12): 2093-105, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27087357

RESUMO

Description of α-linolenic acid (cis-9,cis-12,cis-15-18 : 3, ALA) metabolism in the rumen is incomplete. Ruminal digesta samples were incubated with ALA and buffer containing water or deuterium oxide to investigate the products and mechanisms of ALA biohydrogenation. Geometric Δ9,11,15-18 : 3 isomers were the main intermediates formed from ALA. An increase in the n+1 isotopomers of Δ9,11,15-18 : 3 was due to 2H labelling at C-13. Isomers of Δ9,11,13-18 : 3, cis-7,cis-12,cis-15-18 : 3 and cis-8,cis-12,cis-15-18 : 3 were also formed. No increase in n+1 isotopomers of Δ7,12,15-18 : 3 or Δ8,12,15-18 : 3 was detected. Enrichment in n+2 isotopomers of 18 : 2 products indicated that ALA metabolism continued via the reduction of 18 : 3 intermediates. Isomers of Δ9,11,15-18 : 3 were reduced to Δ11,15-18 : 2 labelled at C-9 and C-13. ALA resulted in the formation of Δ11,13-18 : 2 and Δ12,14-18 : 2 containing multiple 2H labels. Enrichment of the n+3 isotopomer of Δ12,15-18 : 2 was also detected. Metabolism of ALA during incubations with rumen contents occurs by one of three distinct pathways. Formation of Δ9,11,15-18 : 3 appears to be initiated by H abstraction on C-13. Octadecatrienoic intermediates containing cis-12 and cis-15 double bonds are formed without an apparent H exchange with water. Labelling of Δ9,11,13-18 : 3 was inconclusive, suggesting formation by an alternative mechanism. These findings explain the appearance of several bioactive fatty acids in muscle and milk that influence the nutritional value of ruminant-derived foods.


Assuntos
Gorduras na Dieta/metabolismo , Digestão , Ácidos Linoleicos Conjugados/biossíntese , Leite/química , Músculos/química , Rúmen/metabolismo , Ácido alfa-Linolênico/metabolismo , Animais , Bovinos , Feminino , Hidrogenação , Isomerismo , Carne/análise , Ruminantes/metabolismo , Ácido alfa-Linolênico/análogos & derivados
2.
J Agric Food Chem ; 63(28): 6466-74, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26125601

RESUMO

Phytoprostanes, autoxidation products of α-linolenic acid, have been studied in several plant species, but information regarding the natural occurrence of this large family of biologically active oxidized lipids in macroalgae is still scarce. In this work, the free phytoprostane composition of 24 macroalgae species belonging to Chlorophyta, Phaeophyta, and Rhodophyta was determined through a recently validated UHPLC-QqQ-MS/MS method. The phytoprostane profiles varied greatly among all samples, F1t-phytoprostanes and L1-phytoprostanes being the predominant and minor classes, respectively. No correlation between the amounts of α-linolenic acid in alga material and phytoprostane content was found. Therefore, it was hypothesized that the observed variability could be species-specific or result from interspecific interactions. This study provides new insight about the occurrence of phytoprostanes in macroalgae and opens doors for future exploitation of these marine photosynthetic organisms as sources of potentially bioactive oxylipins, encouraging their incorporation in food products and nutraceutical and pharmaceutical preparations for human health.


Assuntos
Ácidos Graxos Insaturados/análise , Alga Marinha/química , Ácido alfa-Linolênico/análogos & derivados , Clorófitas/química , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais , Phaeophyceae/química , Rodófitas/química , Espectrometria de Massas em Tandem , Ácido alfa-Linolênico/análise
3.
Biotechnol Lett ; 37(11): 2271-7, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26188993

RESUMO

OBJECTIVE: To improve the production of 10-hydroxy-12,15(Z,Z)-octadecadienoic acid (HODA) from α-linolenic acid in Stenotrophomonas nitritireducens. RESULTS: Cells of the bacterium were permeabilized with 1.25% (v/v) methanol. The optimal conditions for HODA production by permeabilized cells were pH 7, 35 °C, 5% (v/v) DMSO, 50 g cells l(-1), and 22.5 g α-linolenic acid l(-1). Under these conditions, permeabilized cells produced 16.4 g HODA l(-1) after 2 h, with a conversion yield of 73 % (w/w) and a volumetric productivity of 8.2 g l(-1) h(-1). These values were 153 and 230 % of the values for non-permeabilized cells CONCLUSIONS: This is the highest concentration and volumetric and specific productivities of HODA reported thus far.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Stenotrophomonas/metabolismo , Ácido alfa-Linolênico/metabolismo , Biotecnologia , Permeabilidade da Membrana Celular , Stenotrophomonas/química , Stenotrophomonas/citologia , Ácido alfa-Linolênico/análogos & derivados
4.
Biochim Biophys Acta ; 1851(4): 446-55, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25463478

RESUMO

Cyclic oxygenated metabolites are formed in vivo through non-enzymatic free radical reaction of n-6 and n-3 polyunsaturated fatty acids (PUFAs) such as arachidonic (ARA C20:4 n-6), adrenic (AdA 22:4 n-6), α-linolenic (ALA 18:3 n-3), eicosapentaenoic (EPA 20:5 n-3) and docosahexaenoic (DHA 22:6 n-3) acids. These cyclic compounds are known as isoprostanes, neuroprostanes, dihomo-isoprostanes and phytoprostanes. Evidence has emerged for their use as biomarkers of oxidative stress and, more recently, the n-3PUFA-derived compounds have been shown to mediate bioactivities as secondary messengers. Accordingly, this review will focus on the cyclic oxygenated metabolites generated from AdA, ALA, EPA and DHA. This article is part of a Special Issue entitled "Oxygenated metabolism of PUFA: analysis and biological relevance".


Assuntos
Ácidos Docosa-Hexaenoicos/metabolismo , Ácido Eicosapentaenoico/metabolismo , Ácidos Graxos Insaturados/metabolismo , Estresse Oxidativo , Ácido alfa-Linolênico/metabolismo , Animais , Biomarcadores/metabolismo , Ácido Eicosapentaenoico/análogos & derivados , Humanos , Peroxidação de Lipídeos , Oxirredução , Transdução de Sinais , Ácido alfa-Linolênico/análogos & derivados
5.
J Chem Ecol ; 40(5): 484-90, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24817386

RESUMO

Plants attacked by insect herbivores release a blend of volatile organic compounds (VOCs) that serve as chemical cues for host location by parasitic wasps, natural enemies of the herbivores. Volicitin, N-(17-hydroxylinolenoyl)-L-glutamine, is one of the most active VOC elicitors found in herbivore regurgitants. Our previous study revealed that hydroxylation on the 17th position of the linolenic acid moiety of N-linolenoyl-L-glutamine increases by more than three times the elicitor activity in corn plants. Here, we identified N-(18-hydroxylinolenoyl)-L-glutamine (18OH-volicitin) from larval gut contents of tobacco hornworm (THW), Manduca sexta. Eggplant and tobacco, two solanaceous host plants of THW larvae, and corn, a non-host plant, responded differently to this new elicitor. Eggplant and tobacco seedlings emitted twice the amount of VOCs when 18OH-volicitin was applied to damaged leaf surfaces compared to N-linolenoyl-L-glutamine, while both these fatty acid amino acid conjugates (FACs) elicited a similar response in corn seedlings. In both solanaceous plants, there was no significant difference in the elicitor activity of 17OH- and 18OH-volicitin. Interestingly, other lepidopteran species that have 17OH-type volicitin also attack solanaceous plants. These data suggest that plants have developed herbivory-detection systems customized to their herbivorous enemies.


Assuntos
Glutamina/análogos & derivados , Herbivoria , Ácidos Linolênicos/metabolismo , Manduca/fisiologia , Fenômenos Fisiológicos Vegetais , Compostos Orgânicos Voláteis/metabolismo , Ácido alfa-Linolênico/análogos & derivados , Animais , Glutamina/química , Glutamina/metabolismo , Ácidos Linolênicos/química , Manduca/química , Plantas/química , Plântula/fisiologia , Solanum melongena/fisiologia , Nicotiana/fisiologia , Compostos Orgânicos Voláteis/análise , Zea mays/fisiologia , Ácido alfa-Linolênico/química , Ácido alfa-Linolênico/metabolismo
6.
Int J Pharm ; 465(1-2): 143-58, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24524826

RESUMO

The purpose of this report was to demonstrate the effect of amphiphilic polysaccharides-based self-assembling micelles on enhancing the oral absorption of low molecular weight chondroitin sulfate (LMCS) in vitro and in vivo, and identify the transepithelial transport mechanism of LMCS micelles across the intestinal barrier. α-Linolenic acid-low molecular weight chondroitin sulfate polymers(α-LNA-LMCS) were successfully synthesized, and characterized by FTIR, (1)HNMR, TGA/DSC, TEM, laser light scattering and zeta potential. The significant oral absorption enhancement and elimination half-life (t1/2) extension of LNA-LMCS2 in rats were evidenced by intragastric administration in comparison with CS and LMCS. Caco-2 transport studies demonstrated that the apparent permeability coefficient (Papp) of LNA-LMCS2 was significantly higher than that of CS and LMCS (p<0.001), and no significant effects on the overall integrity of the monolayer were observed during the transport process. In addition, α-LNA-LMCS micelles accumulated around the cell membrane and intercellular space observed by confocal laser scanning microscope (CLSM). Furthermore, evident alterations in the F-actin cytoskeleton were detected by CLSM observation following the treatment of the cell monolayers with α-LNA-LMCS micelles, which further certified the capacity of α-LNA-LMCS micelles to open the intercellular tight junctions rather than disrupt the overall integrity of the monolayer. Therefore, LNA-LMCS2 with low cytotoxicity and high bioavailability might be a promising substitute for CS in clinical use, such as treating osteoarthritis, atherosclerosis, etc.


Assuntos
Sulfatos de Condroitina/farmacocinética , Absorção Intestinal , Mucosa Intestinal/metabolismo , Ácido alfa-Linolênico/farmacocinética , Administração Oral , Animais , Células CACO-2 , Varredura Diferencial de Calorimetria , Sobrevivência Celular/efeitos dos fármacos , Química Farmacêutica , Sulfatos de Condroitina/administração & dosagem , Sulfatos de Condroitina/química , Sulfatos de Condroitina/toxicidade , Células HT29 , Meia-Vida , Humanos , Luz , Masculino , Micelas , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Peso Molecular , Permeabilidade , Espectroscopia de Prótons por Ressonância Magnética , Ratos Sprague-Dawley , Espalhamento de Radiação , Espectroscopia de Infravermelho com Transformada de Fourier , Tecnologia Farmacêutica/métodos , Termogravimetria , Ácido alfa-Linolênico/administração & dosagem , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/química , Ácido alfa-Linolênico/toxicidade
7.
Br J Pharmacol ; 169(4): 772-83, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23088259

RESUMO

N-3 Long-chain polyunsaturated fatty acids (n-3 LC-PUFAs), in particular α-linolenic acid (18:3n-3), eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) are receiving much attention because of their presumed beneficial health effects. To explain these, a variety of mechanisms have been proposed, but their interactions with the endocannabinoid system have received relatively little attention so far. However, it has already been shown some time ago that consumption of n-3 LC-PUFAs not only affects the synthesis of prototypic endocannabinoids like anandamide but also stimulates the formation of specific n-3 LC-PUFA-derived conjugates with ethanolamine, dopamine, serotonin or other amines. Some of these fatty amides show overlapping biological activities with those of typical endocannabinoids, whereas others possess distinct and sometimes largely unknown receptor affinities and other properties. The ethanolamine and dopamine conjugates of DHA have been the most investigated thus far. These mediators may provide promising new leads to the field of inflammatory and neurological disorders and for other pharmacological applications, including their use as carrier molecules for neurotransmitters to target the brain. Furthermore, combinations of n-3 LC-PUFA-derived fatty acid amides, their precursors and FAAH inhibitors offer possibilities to optimise their effects in health and disease.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Agonistas de Receptores de Canabinoides/uso terapêutico , Suplementos Nutricionais , Endocanabinoides/uso terapêutico , Ácidos Graxos Ômega-3/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Alcamidas Poli-Insaturadas/uso terapêutico , Acilação , Animais , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/metabolismo , Agonistas de Receptores de Canabinoides/química , Agonistas de Receptores de Canabinoides/metabolismo , Ácidos Docosa-Hexaenoicos/análogos & derivados , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Docosa-Hexaenoicos/uso terapêutico , Dopamina/análogos & derivados , Dopamina/metabolismo , Dopamina/uso terapêutico , Sistemas de Liberação de Medicamentos , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/metabolismo , Ácido Eicosapentaenoico/uso terapêutico , Endocanabinoides/química , Endocanabinoides/metabolismo , Etanolamina/química , Etanolamina/metabolismo , Etanolamina/uso terapêutico , Ácidos Graxos Ômega-3/química , Ácidos Graxos Ômega-3/metabolismo , Óleos de Peixe/química , Peixes , Humanos , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Alcamidas Poli-Insaturadas/química , Alcamidas Poli-Insaturadas/metabolismo , Receptores de Canabinoides/química , Receptores de Canabinoides/metabolismo , Alimentos Marinhos/análise , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/metabolismo , Ácido alfa-Linolênico/uso terapêutico
8.
New Phytol ; 196(2): 574-585, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22937952

RESUMO

Nicotiana attenuata α-DIOXYGENASE1 (α-DOX1) is an oxylipin-forming gene elicited during herbivory by fatty acid amino acid conjugates (FACs) contained in oral secretions of Manduca sexta. To understand the roles of Naα-DOX1 and its major product, 2-hydroxylinolenic acid (2-hydroxylinolenic acid), in N. attenuata's anti-herbivore defenses, we used a transgenic line specifically silenced in Naα-DOX1 expression (ir-α-dox1) and monitored 2-HOT production in M. sexta-damaged tissues and its role in influencing the production of direct defense compounds and resistance to this insect. Attack by M. sexta larvae amplified 2-HOT formation at the feeding sites; a reaction probably facilitated by Naα-DOX1's high pH optimum which allows 2-HOT formation to occur in the more alkaline conditions at the feeding sites or potentially in the insect mouth parts after the leaf tissue is ingested. Manduca sexta larvae performed better on ir-α-dox1 plants than on wild-type (WT) plants as a result of attenuated herbivory-specific JA and 2-HOT bursts as well as JA-inducible well-established defenses (nicotine, caffeoylputrescine and trypsin proteinase inhibitors). Repeated applications of 2-HOT to wounds before insect feeding partly amplified JA-controlled defenses and restored the resistance of ir-α-dox1 plants. We conclude that 2-HOT, produced by attack-activated α-DOX1 activity, participates in defense activation during insect feeding.


Assuntos
Dioxigenases/metabolismo , Herbivoria , Manduca/fisiologia , Nicotiana/enzimologia , Nicotiana/imunologia , Ácido alfa-Linolênico/biossíntese , Animais , Ciclopentanos/metabolismo , Inativação Gênica/efeitos dos fármacos , Herbivoria/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/fisiologia , Manduca/efeitos dos fármacos , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/parasitologia , Transdução de Sinais/efeitos dos fármacos , Nicotiana/efeitos dos fármacos , Nicotiana/parasitologia , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/química , Ácido alfa-Linolênico/farmacologia
9.
J Plant Physiol ; 169(18): 1815-20, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-22902207

RESUMO

We examined the relationship between temperature (15-35°C) and flower induction as it is influenced by linolenic acid (LA) cascade products, lipoxygenase (LOX; EC 1.13.11.12), allene oxide synthase (AOS; EC 4.2.1.92), and allene oxide cyclase (AOC; EC 5.3.99.6) generated in morning glory (Pharbitis nil Choisy). The maximum amount of LOX protein was detected when plants were grown at 30°C, whereas endogenous AOS and AOC proteins were markedly accumulated at 15°C. Although both test levels of 9(S)- and 13(S)-hydroperoxy linolenic acid (HPOT) showed similar temperature dependencies, reflecting the profile of LOX, the relative amount of 13(S)-HPOT was much higher than that of 9(S)-HPOT, regardless of temperature regime. This implied a faster reaction pathway to 9,10-α-ketol octadecadienoic acid (KODA) in the LA cascade. In the 13(S)-HPOT pathway, the highest level of endogenous jasmonic acid (JA) was observed at 15°C. Our results suggest that at a high temperature (30°C), 9(S)-HPOT may be readily metabolized into KODA to promote flower bud formation. By contrast, at a low temperature, high levels of AOS and AOC result in an accumulation of JA that inhibits this developmental process. Accordingly, depending on the growing temperature, flower bud formation in P. nil is possibly regulated by the interactions among LOX metabolites, with KODA serving as a promoter and JA as an inhibitor.


Assuntos
Ciclopentanos/metabolismo , Ipomoea nil/enzimologia , Lipoxigenase/metabolismo , Oxilipinas/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Temperatura , Ácido alfa-Linolênico/metabolismo , Cicloexanos/metabolismo , Ciclopentanos/farmacologia , Compostos de Epóxi/metabolismo , Flores/enzimologia , Flores/genética , Flores/crescimento & desenvolvimento , Flores/fisiologia , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Oxirredutases Intramoleculares/genética , Oxirredutases Intramoleculares/metabolismo , Ipomoea nil/genética , Ipomoea nil/crescimento & desenvolvimento , Ipomoea nil/fisiologia , Lipoxigenase/genética , Oxilipinas/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Folhas de Planta/fisiologia , Transdução de Sinais , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/química
10.
Biochim Biophys Acta ; 1821(7): 980-8, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22521763

RESUMO

In this study, we compared the cytotoxic effects of natural conjugated linolenic acids (CLnAs) on human adenocarcinoma cells (DLD-1) in vitro, with the goal of finding CLnA isomers with strong cytotoxic effects. The antitumor effect of the CLnA with the strongest cytotoxic effect was then examined in mice. The results showed that all CLnA isomers have strong cytotoxic effects on DLD-1 cells, with jacaric acid (JA) having the strongest effect. Examination of the mechanism of cell death showed that CLnAs induce apoptosis in DLD-1 cells via lipid peroxidation. The intracellular levels of incorporated CLnAs were measured to examine the reason for differences in cytotoxic effects. These results showed that JA was taken into cells efficiently. Collectively, these results suggest that the cytotoxic effect of CLnAs is dependent on intracellular incorporation and induction of apoptosis via lipid peroxidation. JA also had a strong preventive antitumor effect in vivo in nude mice into which DLD-1 cells were transplanted. These results suggest that JA can be used as a dietary constituent for prevention of cancer.


Assuntos
Adenocarcinoma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/farmacologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Transporte Biológico/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Humanos , Isomerismo , Peroxidação de Lipídeos/efeitos dos fármacos , Camundongos , Camundongos Nus , Transplante de Neoplasias , Transplante Heterólogo , Células Tumorais Cultivadas
11.
J Med Chem ; 54(23): 8148-60, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-22007676

RESUMO

Toll-like receptor 2-agonistic lipopeptides typified by S-[2,3-bis(palmitoyloxy)-(2RS)-propyl]-R-cysteinyl-S-serine (PAM(2)CS) compounds are potential vaccine adjuvants. In continuation of previously reported structure-activity relationships on this chemotype, we have determined that at least one acyl group of optimal length (C(16)) and an appropriately oriented ester carbonyl group is essential for TLR2-agonistic activity. The spacing between one of the palmitoyl ester carbonyl and the thioether is crucial to allow for an important H-bond, which observed in the crystal structure of the lipopeptide:TLR2 complex; consequently, activity is lost in homologated compounds. Penicillamine-derived analogues are also inactive, likely due to unfavorable steric interactions with the carbonyl of Ser 12 in TLR2. The thioether in this chemotype can be replaced with a selenoether. Importantly, the thioglycerol motif can be dispensed with altogether and can be replaced with a thioethanol bridge. These results have led to a structurally simpler, synthetically more accessible, and water-soluble analogue possessing strong TLR2-agonistic activities in human blood.


Assuntos
Adjuvantes Imunológicos/síntese química , Lipopeptídeos/síntese química , Receptor 2 Toll-Like/agonistas , Adjuvantes Imunológicos/farmacologia , Animais , Humanos , Ácidos Linoleicos/síntese química , Ácidos Linoleicos/imunologia , Ácidos Linoleicos/farmacologia , Lipopeptídeos/imunologia , Lipopeptídeos/farmacologia , Camundongos , Modelos Moleculares , Estrutura Molecular , Solubilidade , Estereoisomerismo , Relação Estrutura-Atividade , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/síntese química , Ácido alfa-Linolênico/imunologia , Ácido alfa-Linolênico/farmacologia
12.
Trends Plant Sci ; 16(6): 294-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21354852

RESUMO

The recognition of insect and pathogen attack requires the plant's ability to perceive chemical cues generated by the attacker. In contrast to the recognition of microbe-associated molecular patterns and effectors, little is known about the molecular recognition of herbivore-associated elicitors (HAEs) and the signaling mechanisms operating in plants after their perception. HAE perception depends strongly on the natural history of both plants and insects and it is therefore expected that many of the responses induced by different HAEs are specific to the species involved in the interaction. The interaction between Nicotiana attenuata and the specialist lepidopteran Manduca sexta presents a relevant biological system to understand HAE perception and signal transduction systems in plants.


Assuntos
Glutamina/análogos & derivados , Nicotiana/metabolismo , Folhas de Planta/metabolismo , Transdução de Sinais , Ácido alfa-Linolênico/análogos & derivados , Animais , Ciclopentanos/metabolismo , Comportamento Alimentar , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glutamina/metabolismo , Interações Hospedeiro-Parasita , Ácidos Linolênicos/metabolismo , Manduca/fisiologia , Oxilipinas/metabolismo , Folhas de Planta/parasitologia , Nicotiana/genética , Nicotiana/parasitologia , Ácido alfa-Linolênico/metabolismo
13.
Proc Natl Acad Sci U S A ; 106(44): 18820-4, 2009 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-19843694

RESUMO

Transient receptor potential vanilloid 1 (TRPV1) plays a major role in hyperalgesia and allodynia and is expressed both in the peripheral and central nervous systems (CNS). However, few studies have evaluated mechanisms by which CNS TRPV1 mediates hyperalgesia and allodynia after injury. We hypothesized that activation of spinal cord systems releases endogenous TRPV1 agonists that evoke the development of mechanical allodynia by this receptor. Using in vitro superfusion, the depolarization of spinal cord triggered the release of oxidized linoleic acid metabolites, such as 9-hydroxyoctadecadienoic acid (9-HODE) that potently activated spinal TRPV1, leading to the development of mechanical allodynia. Subsequent calcium imaging and electrophysiology studies demonstrated that synthetic oxidized linoleic acid metabolites, including 9-HODE, 13-HODE, and 9 and 13-oxoODE, comprise a family of endogenous TRPV1 agonists. In vivo studies demonstrated that intrathecal application of these oxidized linoleic acid metabolites rapidly evokes mechanical allodynia. Finally, intrathecal neutralization of 9- and 13-HODE by antibodies blocks CFA-evoked mechanical allodynia. These data collectively reveal a mechanism by which an endogenous family of lipids activates TRPV1 in the spinal cord, leading to the development of inflammatory hyperalgesia. These findings may integrate many pain disorders and provide an approach for developing analgesic drugs.


Assuntos
Hiperalgesia/complicações , Hiperalgesia/patologia , Inflamação/complicações , Medula Espinal/metabolismo , Canais de Cátion TRPV/metabolismo , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Linhagem Celular , Adjuvante de Freund/farmacologia , Hiperalgesia/fisiopatologia , Inflamação/fisiopatologia , Ativação do Canal Iônico/efeitos dos fármacos , Ligantes , Masculino , Potenciais da Membrana/efeitos dos fármacos , Camundongos , Oxirredução/efeitos dos fármacos , Dor/complicações , Dor/patologia , Dor/fisiopatologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/metabolismo , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Canais de Cátion TRPV/agonistas
14.
Biosci Biotechnol Biochem ; 73(8): 1883-5, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19661708

RESUMO

Volicitin [N-(17-hydroxylinolenoyl)-L-glutamine] has previously been identified from the lepidopteran larval regurgitant as an elicitor of plant volatile emission. The efficient incorporation of free oxygen into volicitin by Spodoptera litura larvae is demonstrated here by rearing them under (18)O(2) for three days. (18)O-labeling of the hydroxyl group of volicitin was confirmed by liquid chromatography/mass spectrometry-ion trap-time-of-flight (LC/MS-IT-TOF) and suggests the activity of a monooxygenase in volicitin biosynthesis.


Assuntos
Glutamina/análogos & derivados , Oxigênio/metabolismo , Spodoptera/metabolismo , Ácido alfa-Linolênico/análogos & derivados , Animais , Glutamina/metabolismo , Hidroxilação , Marcação por Isótopo , Larva/metabolismo , Espectrometria de Massas , Oxirredução , Oxigênio/química , Ácido alfa-Linolênico/metabolismo
15.
Proc Natl Acad Sci U S A ; 106(2): 653-7, 2009 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-19124770

RESUMO

In response to insect attack, many plants exhibit dynamic biochemical changes, resulting in the induced production of direct and indirect defenses. Elicitors present in herbivore oral secretions are believed to positively regulate many inducible plant defenses; however, little is known about the specificity of elicitor recognition in plants. To investigate the phylogenic distribution of elicitor activity, we tested representatives from three different elicitor classes on the time course of defense-related phytohormone production, including ethylene (E), jasmonic acid (JA), and salicylic acid, in a range of plant species spanning angiosperm diversity. All families examined responded to at least one elicitor class with significant increases in E and JA production within 1 to 2 h after treatment, yet elicitation activity among species was highly idiosyncratic. The fatty-acid amino acid conjugate volicitin exhibited the widest range of phytohormone and volatile inducing activity, which spanned maize (Zea mays), soybean (Glycine max), and eggplant (Solanum melongena). In contrast, the activity of inceptin-related peptides, originally described in cowpea (Vigna unguiculata), was limited even within the Fabaceae. Similarly, caeliferin A16:0, a disulfooxy fatty acid from grasshoppers, was the only elicitor with demonstrable activity in Arabidopsis thaliana. Although precise mechanisms remain unknown, the unpredictable nature of elicitor activity between plant species supports the existence of specific receptor-ligand interactions mediating recognition. Despite the lack of an ideal plant model for studying the action of numerous elicitors, E and JA exist as highly conserved and readily quantifiable markers for future discoveries in this field.


Assuntos
Comportamento Alimentar , Magnoliopsida/fisiologia , Reguladores de Crescimento de Plantas , Fenômenos Fisiológicos Vegetais , Animais , Ciclopentanos , Etilenos , Glutamina/análogos & derivados , Glutamina/metabolismo , Glutamina/farmacologia , Insetos , Magnoliopsida/química , Oxilipinas , Especificidade da Espécie , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/metabolismo , Ácido alfa-Linolênico/farmacologia
16.
Bioorg Med Chem ; 16(23): 10043-8, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18952445

RESUMO

(12Z,15Z)-9-Hydroxy-10-oxooctadeca-12,15-dienoic acid (1) and norepinephrine (2) undergo cycloaddition to afford FN1 (3) and FN2 (4), both of which induce flowering in Lemna paucicostata. Although the derivatives of 1 were suggested to also yield FN-like compounds after reacting with 2, their structures have not been elucidated. In this report, we investigated the structure and stereochemistry of seven novel FN analogs. These analogs were shown to be formed in the same regio- and stereocontrolled manner as FNs. Moreover, the activity of FN analogs on flowering induction was investigated, and we determined that all analogs, except for compound 8, were effective flowering inducers for L. paucicostata.


Assuntos
Flores/efeitos dos fármacos , Ácido alfa-Linolênico/análogos & derivados , Ácido alfa-Linolênico/farmacologia , Ácidos Graxos Insaturados/química , Ácidos Graxos Insaturados/metabolismo , Flores/crescimento & desenvolvimento , Flores/metabolismo , Ipomoea nil/efeitos dos fármacos , Ipomoea nil/genética , Norepinefrina/química , Relação Estrutura-Atividade , Fatores de Tempo , Ácido alfa-Linolênico/síntese química
17.
J Agric Food Chem ; 56(13): 4982-6, 2008 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-18553913

RESUMO

Geometrical isomers of 2,4,6-nonatrienal have been reported from a variety of food- and insect-related sources. It was discovered recently that the eggplant flea beetle, Epitrix fuscula, uses the (2 E,4 E,6 Z) and (2 E,4 E,6 E) isomers as components of its male-produced aggregation pheromone. Here, we learned that the related species, E. hirtipennis, also emits a blend of 2,4,6-nonatrienals, including isomers not previously characterized. Patterns in emission and response suggest a pheromonal function. In an effort to acquire standards to aid in identification, we found that exposing (2 E,4 E,6 E)-2,4,6-nonatrienal (or other available 2,4,6-nonatrienals) to light readily generated a mixture of six geometrical isomers. Configurations of these were determined by NMR, and chromatographic properties (GC and HPLC) were documented. On the basis of chromatographic comparison to these standards, the most abundant, new compound from E. hirtipennis was concluded to be (2 E,4 Z,6 Z)-2,4,6-nonatrienal. Minor components from both E. hirtipennis and E. fuscula were also characterized. The analytical approach given here would also be of use in the food industry, where 2,4,6-nonatrienals are important as aroma compounds.


Assuntos
Besouros/química , Feromônios/química , Ácido alfa-Linolênico/análogos & derivados , Animais , Cromatografia Líquida de Alta Pressão , Besouros/fisiologia , Isomerismo , Masculino , Espectrometria de Massas , Ressonância Magnética Nuclear Biomolecular , Feromônios/metabolismo , Padrões de Referência , Ácido alfa-Linolênico/química , Ácido alfa-Linolênico/metabolismo
18.
Biosci Biotechnol Biochem ; 71(2): 607-10, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17284824

RESUMO

We introduced efficient incorporation of unsaturated fatty acids into volicitin [N-(17-hydroxylinolenoyl)-L-glutamine] and N-linolenoyl-L-glutamine, insect-derived elicitors of plant volatiles, in the common cutworms Spodoptera litura by the incubation of larval gut tissues with unsaturated (linolenic, linoleic, and oleic acids) or saturated fatty acids (palmitic and stearic acids) sodium salt, and L-[alpha-(15)N]glutamine.


Assuntos
Ácidos Graxos Insaturados/metabolismo , Glutamina/análogos & derivados , Spodoptera/metabolismo , Ácido alfa-Linolênico/análogos & derivados , Animais , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Insaturados/química , Cromatografia Gasosa-Espectrometria de Massas , Glutamina/metabolismo , Larva/metabolismo , Lactuca/química , Espectrometria de Massas , Folhas de Planta/química , Ácido alfa-Linolênico/metabolismo
19.
Biosci Biotechnol Biochem ; 70(9): 2185-90, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16960380

RESUMO

Volicitin [N-(17-hydroxylinolenoyl)-L-glutamine] and N-linolenoyl-L-glutamine are known as insect-produced plant volatile elicitors. The absolute configuration of the hydroxylinolenoyl moiety of volicitin from three noctuid species, Helicoverpa armigera, Mythimna separata and Spodoptera litura, was determined to be all 17S in high enantiomeric excess. When treated with 30 pmol of (17S)- and (17R)-volicitin, corn seedlings were induced to release volatiles, there being no significant difference in the amount released between the two isomers. On the other hand, N-linolenoyl-L-glutamine was only about 30% as active as volicitin. Among several synthesized N-linolenoylamino acid conjugates, only the L-glutamine conjugate induced the emission of volatile organic compounds. These results show that the L-glutamine moiety of volicitin played a more critical role than the hydroxyl moiety, although both moieties affected the elicitor activity inducing the release of volatiles.


Assuntos
Glutamina/análogos & derivados , Lepidópteros/metabolismo , Ácido alfa-Linolênico/análogos & derivados , Animais , Cromatografia Gasosa-Espectrometria de Massas , Glutamina/química , Glutamina/farmacologia , Espectroscopia de Ressonância Magnética , Conformação Molecular , Plântula/efeitos dos fármacos , Plântula/metabolismo , Relação Estrutura-Atividade , Terpenos/metabolismo , Zea mays/efeitos dos fármacos , Zea mays/metabolismo , Ácido alfa-Linolênico/química , Ácido alfa-Linolênico/farmacologia
20.
Anal Biochem ; 354(1): 111-26, 2006 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-16712763

RESUMO

Hydroperoxides of polyunsaturated fatty acids can be transformed to epoxyalcohols and keto fatty acids by metal enzymes, hematin, and various catalysts. In the current study, we used hematin to transform 9-hydroperoxy-10E,12Z-octadecadienoic acid and 13-hydroperoxy-9Z,11E-octadecadienoic acid to epoxyalcohols (with trans epoxide configuration) and to keto fatty acids. The products were separated by normal phase high-performance liquid chromatography (NP-HPLC) and analyzed using postcolumn addition of isopropanol/water and online negative ion electrospray ionization mass spectrometry (MS). The tandem MS (MS/MS) spectra were studied using analogs prepared from [9,10,12,13-2H4]linoleic acid (18:2n-6) and from alpha-linolenic acid (18:3n-3). We also studied the MS/MS spectra of epoxyalcohols formed from 11-hydroperoxy- and 8-hydroperoxy-9Z,12Z-octadecadienoic acids. Results were confirmed by MS/MS analysis of a series of authentic standards. MS/MS ions of 9-keto-10E,12Z-octadecadienoic acid and 13-keto-9Z,11E-octadecadienoic acid could be explained by keto-enol tautomerism. MS/MS spectra of regioisomeric allylic epoxyalcohols differed in relative intensities of characteristic ions. The MS/MS spectra of the epoxyalcohols with 1-hydroxy-2,3-epoxy-4Z-pentene or 3-hydroxy-1,2-epoxy-4Z-pentene elements were virtually identical and showed two characteristic ions that differed by 30 in m/z values (CH(OH)). The results suggested that epoxide migration (Payne rearrangement) occurred during collision-induced dissociation. We conclude that regioisomeric allylic epoxyalcohols can be identified by their MS/MS spectra, whereas regioisomeric epoxyalcohols can be identified by MS/MS in combination with their retention times on NP-HPLC.


Assuntos
Cromatografia Líquida/métodos , Ácido Linoleico/análise , Ácido Linoleico/química , Espectrometria de Massas/métodos , Ácido alfa-Linolênico/análise , Ácido alfa-Linolênico/química , Catálise , Hemina/metabolismo , Hemina/farmacologia , Peróxidos Lipídicos/metabolismo , Lipoxigenase/metabolismo , Oxigenases/metabolismo , Estereoisomerismo , Ácido alfa-Linolênico/análogos & derivados
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