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Caracterização química e avaliação da atividade antioxidante e citotóxica do extrato da soja (Glycine max) biotransformada pelo fungo Aspergillus awamori / Chemical characterization and evaluation of the antioxidant and cytotoxic activity of the soybean (Glycine max) extract biotransformed by the Aspergillus awamoriVanessa Silveira Fortes 09 August 2011 (has links)
A soja (Glycine max) contém uma variedade de compostos com comprovada atividade biológica, tais como as isoflavonas, que estão presentes em diferentes formas, glicosiladas e agliconas. Além disso, a soja contém uma grande quantidade de proteínas, que são consideradas fontes de peptídeos bioativos. As isoflavonas agliconas, daidzeína e genisteína, possuem maior atividade antioxidante que as glicosiladas, daidzina e genistina. No entanto, os grãos de soja são ricos nas formas glicosiladas das isoflavonas. Estudos mostram que a biotransformação da soja, por micro-organismos e enzimas, leva ao aumento dos teores das isoflavonas agliconas, as quais são liberadas pela ação de enzimas -glicosidases, que clivam as ligações -glicosídicas das isoflavonas glicosiladas, e também pode possibilitar a hidrólise das proteínas da soja. Além disso, pesquisadores têm demonstrado aumento na atividade antioxidante e na prevenção e/ou supressão de certos cânceres após biotransformação da soja. Neste contexto, foi realizada a biotransformação da soja pelo fungo A. awamori, e por uma mistura enzimática, proveniente do processo fermentativo deste fungo na soja. Os extratos da soja biotransformada, não biotransformada, e o extrato comercial isoflavin beta®, rico em isoflavonas, foram avaliados quanto aos perfis cromatográficos, teores de daidzeína, genisteína, proteínas, aminoácidos e/ou peptídeos, potencial antioxidante e atividade citotóxica frente a células de fibroblasto e melanoma. O modo de morte celular das células de melanoma, necrose ou apoptose, também foi avaliado. A biotransformação da soja, pelos dois processos, resultou em extratos enriquecidos com isoflavonas agliconas e aminoácidos e/ou peptídeos, e com maior atividade antioxidante que o extrato da soja não biotransformada. Os dois processos de biotransformação da soja resultaram em extratos com características químicas e biológicas diferentes. O conteúdo de daidzeína, proteínas, aminoácidos e/ou peptídeos encontrados no extrato da soja biotransformada pelo fungo foram 6%, 56% e 357%, respectivamente, superiores ao extrato da soja biotransformada pela mistura enzimática. Ao contrário do observado para o teor de genisteína que foi 48% maior no extrato da soja biotransformada pela mistura enzimática. O extrato da soja biotransformada pelo fungo apresentou maior atividade antioxidante que o extrato da soja biotransformada pela mistura enzimática, além disso, foi o único dos extratos aqui estudados que apresentou citotoxicidade seletiva para as células de melanoma, induzindo morte celular por apoptose destas células cancerosas. Sendo assim, os resultados obtidos pelo extrato da soja biotransformada pelo fungo A. awamori fornecem boas perspectivas para futura utilização deste extrato como antitumoral. / Soybean (Glycine max) contains a variety of compounds with proven biological activity, such as isoflavones, which are present in different forms, glycosides and aglycones. In addition, soybean contains a lot of proteins, which are considered sources of bioactive peptides. The aglycone isoflavones, daidzein and genistein, have higher antioxidant activity than the glucoside ones, daidzin and genistin. However, soybean grains are rich in the glycosylated forms of isoflavones. Studies have shown that the soybean biotransformation, by microorganisms and enzymes, lead to increased levels of aglycone isoflavones, which are released by the action of -glycosidase enzymes, which cleave the -glycosidic bonds of isoflavone glucosides, and can also allow the hydrolysis of soybean proteins. Additionally, researchers have shown an increase in the antioxidant activity and in the prevention and/or suppression of certain cancers after soybean biotransformation. In this context, it was performed the biotransformation of soybeans with the fungus A. awamori, and with an enzyme mixture, from the fermentation process of the fungus in soybean. The biotransformed, the non biotransformed soybean extracts and the marketed isoflavin beta® extract rich in isoflavones, were evaluated regarding their chromatographic profiles, levels of daidzein, genistein, proteins, amino acids and/or peptides, the antioxidant potential and the cytotoxic activity against melanoma cells and fibroblasts. The mode of cell death of melanoma cells, necrosis or apoptosis, was also evaluated. The biotransformation of soybean by the two processes resulted in extracts enriched with aglycone isoflavones and aminoacids and/or peptides, and with antioxidant activity higher than the non biotransformed soybean extract. The two processes of soybean biotransformation resulted in extracts with different chemical and biological characteristics. The contents of daidzein, proteins, aminoacids and/or peptides found in soybean extract biotransformed by the fungus were 6%, 56% and 357%, respectively, higher than the soybeam extract biotransformed by the enzyme mixture. Contrary to what was observed with the genistein content that was 48% higher in the soybean extract biotransformed by the enzyme mixture. The soybean extract biotransformed by the fungus had a higher antioxidant activity than the soybean extract biotransformed by the enzyme mixture, moreover, it was the unique extract among the ones studied in this work that showed selective cytotoxicity to melanoma cells, inducing cell death by apoptosis of these cancer cells. Thus, the obtained results of the soybean extract biotransformed by the fungus A. awamori provide good prospects for future use of this extract as antitumoral.
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Impact of Short-Term Isoflavone Intervention in Polycystic Ovary Syndrome (PCOS) Patients on Microbiota Composition and MetagenomicsHaudum, Christoph, Lindheim, Lisa, Ascani, Angelo, Trummer, Christian, Horvath, Angela, Münzker, Julia, Obermayer-Pietsch, Barbara 20 April 2023 (has links)
Background: Polycystic ovary syndrome (PCOS) affects 5–20% of women of reproductive age worldwide and is associated with disorders of glucose metabolism. Hormone and metabolic signaling may be influenced by phytoestrogens, such as isoflavones. Their endocrine effects may modify symptom penetrance in PCOS. Equol is one of the most active isoflavone metabolites, produced by intestinal bacteria, and acts as a selective estrogen receptor modulator. Method: In this interventional study of clinical and biochemical characterization, urine isoflavone levels were measured in PCOS and control women before and three days after a defined isoflavone intervention via soy milk. In this interventional study, bacterial equol production was evaluated using the log(equol: daidzein ratio) and microbiome, metabolic, and predicted metagenome analyses were performed. Results: After isoflavone intervention, predicted stool metagenomic pathways, microbial alpha diversity, and glucose homeostasis in PCOS improved resembling the profile of the control group at baseline. In the whole cohort, larger equol production was associated with lower androgen as well as fertility markers. Conclusion: The dynamics in our metabolic, microbiome, and predicted metagenomic profiles underline the importance of external phytohormones on PCOS characteristics and a potential therapeutic approach or prebiotic in the future.
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Physicochemical Characterization and Isoflavone Profiling of Sourdough Soy BreadYezbick, Gabrielle 30 August 2012 (has links)
No description available.
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Etude du déterminisme génétique des différences de teneurs et de profils en isoflavones dans la graine de soja (Glycine max L. Merrill) / Genetic determinism of isoflavones content and composition in hypocotyls and cotyledons of the soybean seed (Glycine max L. Merrill)Artigot, Marie-Pierre 20 July 2012 (has links)
La graine de soja contient de grandes quantités d'isoflavones (génistéine, daidzéine et glycitéine). En raison de leurs propriétés phytoestrogéniques, ces composés peuvent avoir des effets bénéfiques sur la santé humaine, mais ils peuvent aussi être perçus comme perturbateurs endocriniens, en particulier dans les laits pour nourrissons. La teneur et la composition en isoflavones de la graine diffèrent selon la fraction considérée. Les cotylédons contiennent de la génistéine et de la daidzéine, tandis que les germes, avec une teneur quatre à dix fois supérieure, contiennent majoritairement de la daidzéine et de la glycitéine. Le génotype influence fortement la teneur en isoflavones totales. Le déterminisme du pourcentage des isoflavones est essentiellement génétique. Ce travail porte sur l'étude du déterminisme génétique à l'origine des variations de teneurs et de compositions en isoflavones dans les germes et les cotylédons de la graine, en tenant compte également du net décalage de l'accumulation entre ces deux compartiments, au cours du développement de la graine. Dans un premier temps, les gènes des isoflavone synthases (IFS) de variétés très différenciées pour leurs teneurs et profils d'isoflavones ont été séquencés, puis les expressions des gènes clefs de la biosynthèse (neuf chalcone synthases (CHS), une chalcone réductase (CHR), quatre chalcone isomérases (CHI) et les deux isoflavone synthases (IFS) ont été suivies par RT-PCR quantitative dans les cotylédons et dans les germes, à trois stades critiques du développement de la graine (25, 40 et 60 jours après floraison). La seconde partie de ce travail a été consacrée à l'étude de l'expression de différents gènes candidats de la flavonoïde 6-hydroxylase (F6H) catalysant la première étape de la synthèse de la glycitéine. Le polymorphisme des séquences génomiques IFS1 et IFS2 des isoflavone synthases n'a pas montré de lien avec les différences de teneurs en isoflavones entre les variétés. L'activité transcriptionnelle des gènes de biosynthèse des isoflavones souligne l'existence d'une régulation bien distincte de cette synthèse dans ces deux compartiments. Les taux d'expression des gènes cibles ne sont pas toujours reliés avec les différences de teneurs ou de profils dans les germes et les cotylédons, suggérant ainsi l'effet prépondérant des régulations post-traductionnelles, notamment dans la formation du complexe multienzymatique de biosynthèse de ces composés. Nous avons aussi mis en évidence une forte expression du gène CHS9 codant pour la chalcone synthase 9, avec un profil correspondant plus à l'accumulation des isoflavones dans le germe que dans les cotylédons. Les gènes CHS7 et CHS8 codant pour les chalcone synthases 7 et 8, déjà signalés comme fortement corrélés à la synthèse des isoflavones, sont plus liés à l'accumulation dans les cotylédons que dans les germes. Ces travaux montrent aussi que le gène F6H signalé dans la littérature ne s'exprime pas dans les germes. En revanche, deux candidats dont la séquence est similaire à 79% ont été étudiés. Le gène F6H3 est le seul à s'exprimer dans la graine, uniquement dans le germe. Son expression n'a pas été détectée dans les germes d'une lignée mutante qui ne produit pas de glycitéine. Ce gène est donc un candidat potentiel clef pour la synthèse de la glycitéine dans le germe. La structure particulière de l'enzyme correspondante pourrait indiquer une forte implication de l'architecture du complexe enzymatique et des contraintes qui en découlent dans l'utilisation préférentielle d'une voie ou d'une autre dans ce schéma de biosynthèse. / The soybean seed contains large amounts of isoflavones (genistein, daidzein, and glycitein). Owing to their phytoestrogenic properties, these compounds can have beneficial effects on human health, but they can also be considered as endocrine disruptors, for example in infant formulas. The isoflavone content and composition in the seed depend on the considered fraction. The cotyledons contain only genistein and daidzein, while the hypocotyls are four to ten times more concentrated and contain three isoflavones, mostly daidzein and glycitein. The genotype has a strong influence on total isoflavone content, and even more on the percentage of individual isoflavones in cotyledons and hypocotyls. The objective of this work is to investigate the genetic determinism that underlies such contrasted contents and compositions between the two seed fractions, and the relation between main biosynthetic steps and genotypic differences. First, the genes of isoflavone synthases (IFS) were sequenced in varieties with highly contrasted content and composition. The expression of different keys genes of the biosynthesis (nine chalcone synthases (CHS), a chalcone reductase (CHR), four chalcone isomerases (CHI) and the two isoflavone synthases (IFS) have then been followed by quantitative RT - PCR in the cotyledons and hypocotyls, at three critical stages of seed development (25, 40 and 60 days after flowering). Second, the expression of different candidate genes for the flavonoid 6-hydroxylase (F6H) which catalyzes the first step in the synthesis of the glycitein has been investigated. The polymorphism of the genomic sequences IFS1 and IFS2 of isoflavone synthases was not correlated with differences in isoflavone contents. The transcriptional activity of key genes of the biosynthesis of isoflavones pointed out the existence of a distinct regulation of isoflavone biosynthesis between the two seed fractions. The expression levels of target genes were not always related to differences in isoflavone content or compositions in the hypocotyls and cotyledons. This suggests the overriding effect of post-translational regulation, especially in the formation of multienzyme complex of biosynthesis of these compounds. The chalcone synthase gene CHS9 was highly expressed, with a profile similar to the accumulation of isoflavones in hypocotyls. The chalcone synthase genes CHS7 and CHS8 expressions, already reported as highly correlated to the biosynthesis of isoflavones were more related to accumulation in the cotyledons than in hypocotyls. This work has also shown that the F6H gene, reported in the literature was not expressed in the hypocotyls. However, two candidates with as highly similar coding sequence (79%) have been studied. The F6H3 gene is the only one expressed in the seed, more precisely in the hypocotyls but it was not expressed in the cotyledons. Moreover, it was not expressed in a mutant line which did not accumulate glycitein. This gene is therefore a key potential candidate for the synthesis of the glycitein in hypocotyls. The particular structure of the corresponding enzyme may indicate a strong involvement of the architecture of the multienzyme complex of isoflavones biosynthesis and the constraints arising in the preferential use of a track or another in this scheme of biosynthesis.
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Prospection and identification of bioactive compounds in the products of the soybean oil ethanolic extraction / Prospecção e identificação de compostos de atividade antioxidante em miscelas etanólicas de óleo de sojaBorges, Larissa Braga Bueno 12 April 2019 (has links)
Soybean oil is commercially obtained through an extraction process using hot commercial hexane. This toxic solvent, derived from petroleum, must be subsequently evaporated before the oil can be submitted to refining steps prior to storage and transportation or directly moving to biodiesel synthesis. Extraction of soybean oil with ethanol, a renewable, low-toxicity solvent, results in the production of an oil-rich miscella that can be directly esterified to produce ethyl esters (biodiesel) without the need for oil-refining steps and evaporation of the solvent. This extraction also generates an oil-poor miscella that has been successfully reinserted in further extractions as the solvent. The theoretical bases of the ethanolic extraction of soybean oil have been established by the works of many authors, focusing on the insurance of high oil yields. However, the effects of the ethanolic extraction of vegetable oils on the antioxidant profile and oxidative stability of the extraction products have not yet been addressed. This study aimed to increase the knowledge on the antioxidant composition of the rich and poor miscella derived from the extraction of soybean oil using ethanol as solvent. Results showed that although the rich miscella presents lower amounts of tocopherols in comparison to oils extracted with hexane, it contains antioxidant compounds of polar character with high affinity to ethanol, which would not be found in soybean oils extracted with hexane. Among these compounds isoflavones have been identified and quantified. The reuse of the poor miscella in subsequent extractions promotes an increase in the oxidative stability of the rich miscella, possibly, by adding antioxidant compounds with high affinity to ethanol. This effect was also observed in the use of the oil-poor miscella in liquid-liquid washings with waste cooking oil, resulting increase of the induction period. However, consecutive extractions of soybean oil have shown that the increase in the induction period of the oil-rich miscella reaches a limit. This phenomenon may be an indication of pro-oxidant effects, resulting from the increase in the content of the compounds present in the rich-miscella. For this reason, the study of the interactions between different classes of antioxidant compounds present in the soybean ethanolic extraction products may be an excellent way to understand the mechanisms involved in the oxidative stability of complex lipid systems. / O óleo de soja é obtido comercialmente através de um processo de extração a quente utilizando a hexana, também conhecida como hexano comercial. Esse solvente tóxico, derivado de petróleo, deve ser posteriormente evaporado para que o óleo passe por etapas de refino antes de seguir para o armazenamento e transporte ou diretamente para a síntese de biodiesel. A extração de óleo de soja com o etanol, um solvente renovável e de baixa toxicidade, resulta na produção de uma miscela rica em óleo que pode ser diretamente esterificada para produzir ésteres etílicos (biodiesel), sem a necessidade de etapas de refino de óleo e evaporação do solvente. Essa extração gera também uma miscela pobre em óleo que pode ser reutilizada em extrações posteriores como solvente. As bases teóricas da extração etanólica de óleo de soja foram estabelecidas pelos trabalhos de muitos autores, visando maiores rendimentos de extração. No entanto, o perfil antioxidante e a estabilidade oxidativa dos produtos da extração etanólica de óleos vegetais não foram abordados até o momento. Este estudo visou ampliar os conhecimentos sobre a composição antioxidante das miscelas ricas e pobres, oriundas da extração de óleo de soja, utilizando o etanol como solvente. Os resultados evidenciaram que embora a miscela rica apresente quantidades inferiores de tocoferóis em relação a óleos extraídos com hexano, a mesma é acrescida de compostos antioxidantes de natureza polar, devido a afinidade com etanol. Entre esses compostos foram identificadas isoflavonas, que normalmente não são encontradas nos óleos de soja obtidos pela extração com hexano. A reutilização da miscela pobre promove o aumento da estabilidade oxidativa das miscelas ricas, através da adição de compostos antioxidantes de maior afinidade pelo etanol. Esse efeito foi também observado no uso da miscela pobre em lavagens do óleo de fritura, resultando em aumento no período de indução. No entanto, a reutilização de miscelas pobres em extrações consecutivas demonstrou atingir um limite no aumento do período de indução das miscelas ricas. Esse fenômeno pode ser um indício de efeito pró-oxidante decorrente do aumento das concentrações de compostos presentes na miscela rica. Por essa razão, o estudo das interações entre diferentes classes de compostos antioxidantes nas miscelas oriundas da extração de óleo de soja pode ser uma excelente via para a compreensão dos mecanismos envolvidos na estabilidade oxidativa de sistemas lipídicos complexos.
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Teor de isoflavonas e capacidade antioxidante de bebidas à base de soja / Isoflavone contents and antioxidant capacity of soy beveragesCallou, Kátia Rau de Almeida 21 May 2009 (has links)
A soja é a principal fonte de isoflavonas, tendo sido associada a efeitos benéficos à saúde humana, incluindo a redução do risco de câncer, de doenças cardiovasculares, osteoporose e melhora dos sintomas da menopausa. A população brasileira não consome soja tão habitualmente quanto os países asiáticos e, nesse contexto, as bebidas de soja poderiam ser uma forma de incluir essas substâncias bioativas na dieta ocidental. Contudo, trabalhos que avaliem o teor de isoflavonas desses produtos são escassos na literatura, o que justifica o presente trabalho. Amostras de doze marcas comercialmente disponíveis de bebidas de soja (n = 65), incluindo os produtos elaborados com isolado protéico de soja ou extrato de soja e acrescidos de sucos de fruta e/ou ingredientes aromatizantes, foram analisadas quanto ao teor e perfil de isoflavonas, utilizando-se a cromatografia líquida de alta eficiência. A capacidade antioxidante foi mensurada pelo método de sequestro de radicais livres do DPPH e o teor de fenólicos totais pelo método do Folin-Ciocalteau. Os valores da concentração total de isoflavonas e o teor de fenólicos totais mostraram uma grande variação entre as diversas marcas de bebidas de soja, variando de 0,7 a 4,9 mg isoflavonas/200 mL e de 6 a 146 mg equivalentes de catequina/200 mL para as bebidas contendo sucos de fruta. Bebidas de soja de sabor original ou chocolate apresentaram variação do teor de isoflavona de 4 a 13 mg/200 mL e fenólicos totais variando de 38 a 155 mg equivalentes de catequina/200 mL. O teor protéico variou de 0,8 a 6 g/200 mL e mostrou-se positivamente correlacionado ao teor de isoflavonas das amostras. As formas predominantes de isoflavonas, nos produtos analisados, foram os β- glicosídeos. Os resultados mostraram que o teor e perfil de isoflavonas, assim como os valores de fenólicos totais das bebidas de soja dependem das condições de processamento e que a atividade antioxidante variou significantemente entre os produtos. Os resultados obtidos mostram que o consumo de uma porção de 300 mL de bebida de soja sabor natural poderia resultar em uma ingestão de 20 mg de isoflavonas, o equivalente a ingestão diária Koreana, indicando que as bebidas de soja poderiam representar fontes importantes de isoflavonas para a nossa dieta. Além disso, o teor de isoflavonas solúveis das bebidas de soja diminui com o decorrer do armazenamento associado à redução da solubilidade da proteína de soja. O perfil de isoflavonas e a capacidade antioxidante das bebidas também são alterados. / Soybean is the most important source of isoflavones, which have been associated with beneficial effects in humans, including prevention of cancer, cardiovascular diseases, osteoporosis and relief of menopausal symptoms. Soybean consumption in Brazil is not as significant as in Asian countries and in this context, soy beverages could be a way to include these bioactive substances in ocidental diet. However, studies about isoflavone content in these products are scarce, which accounts for the present work. Samples of 12 different brands of commercially available soy milk drinks (n = 65), including products made from isolated soy protein and soymilk mixed with fruit juices and/or containing flavoring ingredients were analysed for their isoflavone content and profile using highperformance liquid chromatography. The antioxidant activity was measured using 2.2- diphenil-1-picryl-hydrazil (DPPH) free radical method and the total phenolics was determined by Folin-Ciocalteau method. There was a large variation in total isoflavone concentration and total phenolics content among the different brands of soy milks ranging from 0.7 to 4.9 mg isoflavones/200 mL and 6 to 146 mg equivalents of catechin/200 mL of soymilk mixed with fruit juice. For natural or chocolate soy beverages, the isoflavone content varied from 4 to13 mg/200 mL and the total phenolics ranged from 38 to155 mg equivalent of catequina/200 mL. Levels of protein ranged from 0.8 to 6.0 g/200 mL, these values were associated positively with isoflavone content from samples. The β-glycosides were the predominant form of the isoflavones in the products analyzed. The results showed that total isoflavone, phenolic contents and isoflavone profile of soy beverages depends on processing conditions. Also the antioxidant activity varied significantly among products. The results obtained show that the consumption of 300 mL of soy beverage natural flavor would result in an intake of around 20 mg isoflavone, very similar to the Korean daily intake, indicating that soy beverages could represent important sources of isoflavones in our diet. Furthermore, the soluble isoflavone content of soy beverage decreases with the storage time associated with a reduction of the solubility of soy protein. The profile of isoflavones and antioxidant capacity of beverages are also altered.
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Der Einfluss von diätetisch verabreichten Sojaisoflavonen auf den Homocysteinmetabolismus und die Endothelfunktion bei gesunden, postmenopausalen Frauen / The impact of soy isoflavones on homocysteine metabolism and endothelial function in healthy postmenopausal womenReimann, Manja January 2005 (has links)
Homocystein (tHcy) gilt als unabhängiger kardiovaskulärer Risikofaktor und korreliert eng mit einer endothelialen Dysfunktion, welche nichtinvasiv mittels der flussinduzierten Vasodilatation (FMD) messbar ist. Experimentelle Hyperhomocysteinämie ist mit einer reduzierten Bioverfügbarkeit von endothelialen Stickstoffmonoxid (NO) bei gleichzeitig erhöhten Spiegeln des kompetetiven Inhibitors der NO-Biosynthese asymmetrisches Dimethylarginin (ADMA) assoziiert. In-vivo senkt eine Östrogenbehandlung neben tHcy auch die ADMA-Spiegel und verbessert signifikant die Endothelfunktion. Hinsichtlich ihrer Wirkung als selektive Östrogenrezeptormodulatoren wird angenommen, dass Phytoöstrogene, speziell Sojaisoflavone, ähnliche Effekte hervorrufen.<br><br>
Innerhalb einer europäischen, multizentrischen, doppelblinden Interventionsstudie an 89 gesunden, postmenopausalen Frauen wurde der Einfluss von Sojaisoflavonen auf den Homocysteinmetabolismus, den Blutdruck und die in-vivo Endothelfunktion untersucht. Die cross-over Studie umfasste zwei achtwöchige Interventionsperioden, die von einer gleichlangen Wash-out-Phase unterbrochen waren. Die Zuteilung zum Isoflavon- (50 mg/d) oder Plazeboregime für die erste Interventionsphase erfolgte randomisiert. Endpunkterhebungen fanden jeweils in den Wochen 0 und 8 der Interventionsperioden statt.<br><br>
Die renale Ausscheidung von Genistein, Daidzein und Equol war während der Isoflavonintervention signifikant erhöht (P>0,001). Die Phyoöstrogene hatten weder einen Effekt auf die tHcy-Konzentration (P=0,286), noch auf ADMA, Erythrozytenfolat und Vitamin B-12 (P>0,05) im Plasma. Während die Summe aus Nitrat und Nitrit (NOx), welche die NO-Bioverfügbarkeit reflektiert, im Verlaufe der Plazebobehandlung abfiel, wurde ein leichter Anstieg bei der Isoflavonsupplementation beobachtet (Delta Wo8-Wo0: -2,60 [-8,75; 2,25] vs. 1,00 [-6,65; 7,85] µmol/L P<0,001), was zu einem signifikanten Behandlungseffekt führte. Weiterhin wurde eine positive Korrelation zwischen ADMA und Vitamin B-12 gefunden (R=0,252; P=0,018). Die flussinduzierte Vasodilatation (P=0,716), ein Maß für die Endothelfunktion, blieb durch die Isoflavonbehandlung unbeeinflusst, obwohl sich diese über die Zeit insgesamt verbesserte (P>0,001). Bis auf einen marginalen Anstieg des systolischen Wertes (P=0,032) im Vergleich zur Plazebobehandlung blieb der Blutdruck während der Isoflavonintervention unverändert.<br><br>
Im Gegensatz zu Östrogen übten Sojaisoflavone weder einen Einfluss auf die in-vivo Endothelfunktion noch auf die traditionellen und neuen kardiovaskulären Risikofaktoren den Blutdruck, tHcy und ADMA aus. Demzufolge ist der gesundheitliche Nutzen isolierter Isoflavone hinsichtlich einer Prävention hormonmangelbedingter Erkrankungen in gesunden postmenopausalen Frauen fraglich. / Homocysteine (tHcy) is a strong and independent risk factor for cardiovascular disease. Hyperhomocysteinemia contributes to endothelial dysfunction as assessed by flow-mediated vasodilation (FMD). The mechanisms by which homocysteine generates endothelial dysfunction remain incompletely understood although a growing body of data suggests that the bioavailability of nitric oxide (NO) is reduced. The principal competitive inhibitor of endothelial NO-synthase asymmetric dimethylarginine (ADMA) may play a central role in homocysteine related dysfunction as it is derived from homocysteine metabolism. Cardiovascular risk factor modification has suggested beneficial effects of estrogen on endothelial function by lowering homocysteine and ADMA levels. We hypothesize that phytoestrogens particular isoflavones act in a similar manner.<br><br>
The effects of soy isoflavones on homocysteine metabolism and endothelial function were investigated within a multi-centre, double blind, cross-over intervention trial in 89 European postmenopausal women. Subjects consumed either fruit cereal bars with or without soy isoflavones (50 mg/d) for 8 weeks each with a 8 weeks washout period in between. Endpoint measurements were during both treatment phases at baseline and weeks 8, respectively. <br><br>
Urinary phytoestrogens increased significantly after isoflavone intervention (P<0.001). Isoflavone supplementation did affect neither plasma total homocysteine (P=0.286) nor ADMA, vitamin B-12 or folate (P<0.05). Isoflavones had a favorable effect on NO-metabolism assessed by analysis of NO-metabolites (NOx) nitrite and nitrate. While NOx concentration significantly decreased during placebo there was a slight increase after isoflavone supplementation leading to a significant treatment difference (delta wk8-wk0: -2.60 [-8.75; 2.25] vs. 1.00 [-6.65; 7.85] µmol/L P<0.001). There was no association between total homocysteine and ADMA whereas a positive correlation was found for ADMA and vitamin B-12 (R=0.252; P=0.018). The endothelial function model did not demonstrate any difference between either treatment regime (P=0.716), although endothelial function assessed by flow-mediated vasodilation improved in general (P<0.001). A potential adverse effect was noted, with an elevation in systolic blood pressure (P=0.032) whereas diastolic blood pressure and mean arterial pressure remained unaffected.<br><br>
Soy isoflavones did not have beneficial effects on endothelial function as well as on traditional and novel cardiovascular risk factors like plasma homocysteine, blood pressure and ADMA as observed for estrogen treatment. The health benefit of isolated isoflavones in healthy postmenopausal women is questionable.
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Characterisation of oestrogenic properties of Isoflavones derived from Millettia griffoniana Baill.: - Molecular mode of action and tissue selectivity / Charakterisierung von östrogenen Eigenschaften von Isoflavonen aus Millettia griffoniana Baill.: - Untersuchung zu molekulare Wirkungsmechanismen und GewebeselektivitätKetcha Wanda, Germain Jean Magloire 27 July 2006 (has links) (PDF)
Six isoflavones derived from Millettia griffoniana namely, 4’-methoxy-7-O-[(E)-3-methyl-7hydroxymethyl-2,6 octadienyl]isoflavone (7-O-DHF), Griffonianone C (Griff C), 7-O-geranylformononetin (7-O-GF), 3’,4’-dihydroxy-7-O-[(E)-3,7-dimethyl-2,6-octadienyl]isoflavone (7-O-GISO), Griffonianone E (Griff E), 4’-O-geranylisoliquiritigenin (4-O-GIQ) were tested for potential oestrogenic activities in three different oestrogen receptor alpha (ERα) dependent assays, namely a recombinant yeast assay, a reporter gene assay based on stably transfected MCF-7 cells (MVLN cells) and the induction of alkaline phosphatase in Ishikawa cells. The oestrogenic activities of isoflavones from Millettia griffoniana could be completely suppressed by the pure oestrogen antagonist, fulvestrant. The expression of Ki-67, proliferating cell nuclear antigen (PCNA) and cyclin D1 (CD1) mRNA used as indicator of cell proliferation in MCF-7 cells was assayed. Based on these in vitro results, Griff C was further tested in vivo. The main objective of this part of the work was to study the mechanistic basis of the oestrogenicity Three different doses of Griff C (2, 10, or 20 mg/kg BW) of Griff C in ovariectomised Wistar rats. 17β-oestradiol (E2: 10 µg/kg BW) was used as positive control. They were treated daily for three consecutive days and sacrificed 24 hours after receiving the last dose. The whole uterus was removed and weight. Liver and vena cava fragments were also collected and stored together with uteri in liquid nitrogen for subsequent real-time PCR to evaluate the effects of Griff C on the regulation of some relevant oestrogen–responsive genes in the uterus, the liver and the vena cava. The role of Griff C in apoptosis or in cell survival, through mediation of the phosphatidylinositol 3 kinase-Akt (PI3K-Akt) signaling pathway, was also investigated. Western blot analysis revealed that Griff C slightly increased the phosphorylation of Akt at its serine 473 residue. In this work, oestrogenic properties of the isoflavones derived from Millettia griffoniana are described using reporter gene assays and the oestrogen-inducible alkaline phosphatase Ishikawa model for the first time. These in vitro data were verified in vivo showing the regulation of the expression of various relevant oestrogen-responsive genes by Griff C. The spectrum of its activity was clearly similar to that of 17β-oestradiol on uterine hepatic and vena cava tissues of ovariectomised rats except for the proliferative response. However Griff C remained 100 to 1000 times less effective than oestradiol. These findings confirmed that some of the biological effects attributed to Millettia griffoniana are closely related to oestrogen-mediated action.
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Efeitos do tratamento prolongado com isoflavonas de soja no útero, mamas, tecidos adiposo e ósseo de ratas ovariectomizadas / Effects of prolonged treatment with soy isoflavones on the uterus, breast, adipose and bone tissue of ovariectomized ratsRaimunda Ribeiro da Silva 21 March 2013 (has links)
A menopausa, fenômeno fisiológico que ocorre em todas as mulheres, em média, aos 51 anos, é acompanhada em cerca de 80% dos casos de sintomas como fogachos, secura vaginal, irritabilidade e insônia, que interferem na qualidade de vida e na produtividade socioeconômica das mulheres, além de predispô-las a doenças crônico-degenerativas, como arteriosclerose, obesidade e distúrbios cardiovasculares. A terapia de reposição hormonal à base de estrógenos, que visa reduzir os incômodos da menopausa, está associada ao aumento do risco de câncer de mama e do endométrio, como foi demonstrado em estudos científicos. Considerando que as mulheres orientais, consumidoras de soja, apresentam doenças crônico-degenerativas e câncer em taxas inferiores às dos países ocidentais, as isoflavonas da soja têm sido testadas em estudos clínicos e experimentais, porém com obtenção de dados até contraditórios. O presente estudo investigou o efeito da administração crônica de isoflavonas de soja no útero, mamas e tecidos adiposo e ósseo de ratas ovariectomizadas. Quarenta ratas Wistar adultas foram distribuídas em quatro grupos experimentais: a) ovariectomizadas: grupo ISO, recebendo isoflavonas de soja (100mg/kg/dia/v.o.); b) ovariectomizadas: grupo BE, recebendo benzoato de estradiol (10g/kg/dia/s.c.); c) ovariectomizadas: grupo OVX, recebendo salina (0,1ml/100g/dia/v.o.); d) controles: grupo FO, recebendo salina (0,1ml/100g/dia/v.o.). Antes e durante os 90 dias de tratamento, foram analisados os esfregaços vaginais, para acompanhamento do ciclo estral, determinação do peso corporal e do consumo de ração semanal. Após esse período, os animais foram anestesiados e o sangue coletado para análise de estradiol e progesterona séricos, por radioimunoensaio; e lipidograma e glicose, por espectrofotometria. Posteriormente, os animais foram sacrificados e necropsiados, coletando-se o útero, mamas, gordura intra-abdominal e fêmur para macroscopia e pesagem. Os tecidos selecionados para o estudo foram corados em HE, analisados por microscopia óptica e histomorfometria, visando investigar alterações do crescimento celular (software V.S NIH Image-J; imagens digitais-optronicos CCD). No grupo tratado com isoflavonas, o peso corporal diminuiu em relação OVX, no qual ocorreu aumento de peso em comparação aos animais falso-operados. O exame macroscópico revelou que o útero diminuiu de peso nas ratas do grupo ISO, semelhante às do OVX. Além disso, a histopatologia das glândulas endometriais não mostrou alterações entre os grupos ISO e OVX. Contudo, o grupo BE apresentou proliferação glandular, pseudoestratificação epitelial, frequentes mitoses típicas, metaplasia escamosa, infiltrado eosinofílico e hidrométrio. A concentração de estradiol no grupo ISO foi semelhante à do OVX. Porém, no grupo BE, o estradiol e o peso uterino apresentaram-se aumentados em relação ao OVX. Não foram observadas diferenças na histomorfometria mamária entre os grupos. Houve redução no peso do tecido adiposo abdominal no grupo ISO, comparado com o OVX, sem identificação de alterações morfológicas significativas, apenas hipotrofia celular, confirmada pela histomorfometria. Apesar de não ter havido diferenças na concentração de glicose, colesterol total e triglicerídeos, entre os grupos, o colesterol-HDL apresentou aumento no grupo ISO. Não houve diferença na densitometria do fêmur entre os grupos avaliados. Esses resultados indicam que o tratamento crônico com isoflavonas de soja, na dose testada, não induz mudanças significativas no útero, mamas e tecidos adiposo e ósseo, sugerindo segurança no tratamento, sem risco para o desenvolvimento de câncer. / Menopause, physiological phenomenon that occurs in all women, average age 51, is accompanied by about 80% of cases symptoms such as hot flashes, vaginal dryness, irritability and insomnia, which affect the quality of life and socioeconomic productivity women's, and predispose them to chronic degenerative diseases such as atherosclerosis, obesity and cardiovascular disorders. The hormone replacement therapy based on estrogen, which aims to reduce the discomforts of menopause is associated with an increased risk of endometrial and breast cancer, as has been shown in scientific studies. Whereas that women, consuming soy, had lower rates of chronic degenerative diseases and cancer at rates lower than those of Western countries, soy isoflavones have been tested in clinical and experimental studies, but with contradictory results. The present study investigated the effect of chronic administration of soy isoflavones on the uterus, breast, bone and adipose tissues from ovariectomized rats. Forty female Wistar rats were divided into four groups: a) ovariectomized: ISO group receiving soy isoflavones (100mg/kg/dia/vo); b) ovariectomized: EB group receiving estradiol benzoate (10μg/kg/dia/sc); c) ovariectomized: OVX group receiving saline (0.1 ml/100g/dia/vo); d) controls: FO group, receiving saline (0.1 ml/100g/dia/vo). Before and during the 90 days of treatment vaginal smears were analyzed to monitor the estrous cycle, given the body weight and food intake monitored weekly. After this period, the animals were anesthetized and blood was collected for analysis of serum estradiol and progesterone serum by radioimmunoassay, and lipid and glucose by spectrophotometry. Subsequently, the animals were euthanized and necropsied, collecting the uterus, breasts, intra-abdominal fat and femur for macroscopic exam and weighing. The tissues selected for the study were stained with HE and analyzed by light microscopy and histomorphometry, in order to investigated possible changes in cell growth (NIH Image software VS-J;-optronics CCD digital images). In the group treated with isoflavones a decrease in body weight decreased compared OVX in which there was an increase in weight compared to the false-operated animals. Macroscopically, the uterus weight was lower in ISO group, similar to the OVX group. Furthermore, no change was showed in the histopathology of endometrial glands between ISO and OVX groups. The EB group showed glandular proliferation, pseudo-stratified epithelium, frequent mitoses typical squamous metaplasia, and eosinophilic infiltrate and hidrometry. The estradiol concentration in the ISO group was similar to OVX. However, EB group showed increase in estradiol and uterine weight in relation to OVX. No differences in mammary histomorphometry were observed among the four groups. Fat abdominal tissue weight was lower in ISO group compared with OVX group but, no morphological changes were seen on microscopy, only a cellular hipertrophy confirmed by histomorphometry. Although there were no differences in the glucose concentration, total cholesterol and triglycerides among groups, the cholesterol-HDL was increased in the group ISO. There was no difference in femur density among the groups. These results indicate that chronic treatment with soy isoflavones, at the tested dose did not induce significant changes in the uterus, breast, bone and adipose tissues, suggesting safety in handling without risk for development of cancer.
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Efeitos do tratamento prolongado com isoflavonas de soja no útero, mamas, tecidos adiposo e ósseo de ratas ovariectomizadas / Effects of prolonged treatment with soy isoflavones on the uterus, breast, adipose and bone tissue of ovariectomized ratsRaimunda Ribeiro da Silva 21 March 2013 (has links)
A menopausa, fenômeno fisiológico que ocorre em todas as mulheres, em média, aos 51 anos, é acompanhada em cerca de 80% dos casos de sintomas como fogachos, secura vaginal, irritabilidade e insônia, que interferem na qualidade de vida e na produtividade socioeconômica das mulheres, além de predispô-las a doenças crônico-degenerativas, como arteriosclerose, obesidade e distúrbios cardiovasculares. A terapia de reposição hormonal à base de estrógenos, que visa reduzir os incômodos da menopausa, está associada ao aumento do risco de câncer de mama e do endométrio, como foi demonstrado em estudos científicos. Considerando que as mulheres orientais, consumidoras de soja, apresentam doenças crônico-degenerativas e câncer em taxas inferiores às dos países ocidentais, as isoflavonas da soja têm sido testadas em estudos clínicos e experimentais, porém com obtenção de dados até contraditórios. O presente estudo investigou o efeito da administração crônica de isoflavonas de soja no útero, mamas e tecidos adiposo e ósseo de ratas ovariectomizadas. Quarenta ratas Wistar adultas foram distribuídas em quatro grupos experimentais: a) ovariectomizadas: grupo ISO, recebendo isoflavonas de soja (100mg/kg/dia/v.o.); b) ovariectomizadas: grupo BE, recebendo benzoato de estradiol (10g/kg/dia/s.c.); c) ovariectomizadas: grupo OVX, recebendo salina (0,1ml/100g/dia/v.o.); d) controles: grupo FO, recebendo salina (0,1ml/100g/dia/v.o.). Antes e durante os 90 dias de tratamento, foram analisados os esfregaços vaginais, para acompanhamento do ciclo estral, determinação do peso corporal e do consumo de ração semanal. Após esse período, os animais foram anestesiados e o sangue coletado para análise de estradiol e progesterona séricos, por radioimunoensaio; e lipidograma e glicose, por espectrofotometria. Posteriormente, os animais foram sacrificados e necropsiados, coletando-se o útero, mamas, gordura intra-abdominal e fêmur para macroscopia e pesagem. Os tecidos selecionados para o estudo foram corados em HE, analisados por microscopia óptica e histomorfometria, visando investigar alterações do crescimento celular (software V.S NIH Image-J; imagens digitais-optronicos CCD). No grupo tratado com isoflavonas, o peso corporal diminuiu em relação OVX, no qual ocorreu aumento de peso em comparação aos animais falso-operados. O exame macroscópico revelou que o útero diminuiu de peso nas ratas do grupo ISO, semelhante às do OVX. Além disso, a histopatologia das glândulas endometriais não mostrou alterações entre os grupos ISO e OVX. Contudo, o grupo BE apresentou proliferação glandular, pseudoestratificação epitelial, frequentes mitoses típicas, metaplasia escamosa, infiltrado eosinofílico e hidrométrio. A concentração de estradiol no grupo ISO foi semelhante à do OVX. Porém, no grupo BE, o estradiol e o peso uterino apresentaram-se aumentados em relação ao OVX. Não foram observadas diferenças na histomorfometria mamária entre os grupos. Houve redução no peso do tecido adiposo abdominal no grupo ISO, comparado com o OVX, sem identificação de alterações morfológicas significativas, apenas hipotrofia celular, confirmada pela histomorfometria. Apesar de não ter havido diferenças na concentração de glicose, colesterol total e triglicerídeos, entre os grupos, o colesterol-HDL apresentou aumento no grupo ISO. Não houve diferença na densitometria do fêmur entre os grupos avaliados. Esses resultados indicam que o tratamento crônico com isoflavonas de soja, na dose testada, não induz mudanças significativas no útero, mamas e tecidos adiposo e ósseo, sugerindo segurança no tratamento, sem risco para o desenvolvimento de câncer. / Menopause, physiological phenomenon that occurs in all women, average age 51, is accompanied by about 80% of cases symptoms such as hot flashes, vaginal dryness, irritability and insomnia, which affect the quality of life and socioeconomic productivity women's, and predispose them to chronic degenerative diseases such as atherosclerosis, obesity and cardiovascular disorders. The hormone replacement therapy based on estrogen, which aims to reduce the discomforts of menopause is associated with an increased risk of endometrial and breast cancer, as has been shown in scientific studies. Whereas that women, consuming soy, had lower rates of chronic degenerative diseases and cancer at rates lower than those of Western countries, soy isoflavones have been tested in clinical and experimental studies, but with contradictory results. The present study investigated the effect of chronic administration of soy isoflavones on the uterus, breast, bone and adipose tissues from ovariectomized rats. Forty female Wistar rats were divided into four groups: a) ovariectomized: ISO group receiving soy isoflavones (100mg/kg/dia/vo); b) ovariectomized: EB group receiving estradiol benzoate (10μg/kg/dia/sc); c) ovariectomized: OVX group receiving saline (0.1 ml/100g/dia/vo); d) controls: FO group, receiving saline (0.1 ml/100g/dia/vo). Before and during the 90 days of treatment vaginal smears were analyzed to monitor the estrous cycle, given the body weight and food intake monitored weekly. After this period, the animals were anesthetized and blood was collected for analysis of serum estradiol and progesterone serum by radioimmunoassay, and lipid and glucose by spectrophotometry. Subsequently, the animals were euthanized and necropsied, collecting the uterus, breasts, intra-abdominal fat and femur for macroscopic exam and weighing. The tissues selected for the study were stained with HE and analyzed by light microscopy and histomorphometry, in order to investigated possible changes in cell growth (NIH Image software VS-J;-optronics CCD digital images). In the group treated with isoflavones a decrease in body weight decreased compared OVX in which there was an increase in weight compared to the false-operated animals. Macroscopically, the uterus weight was lower in ISO group, similar to the OVX group. Furthermore, no change was showed in the histopathology of endometrial glands between ISO and OVX groups. The EB group showed glandular proliferation, pseudo-stratified epithelium, frequent mitoses typical squamous metaplasia, and eosinophilic infiltrate and hidrometry. The estradiol concentration in the ISO group was similar to OVX. However, EB group showed increase in estradiol and uterine weight in relation to OVX. No differences in mammary histomorphometry were observed among the four groups. Fat abdominal tissue weight was lower in ISO group compared with OVX group but, no morphological changes were seen on microscopy, only a cellular hipertrophy confirmed by histomorphometry. Although there were no differences in the glucose concentration, total cholesterol and triglycerides among groups, the cholesterol-HDL was increased in the group ISO. There was no difference in femur density among the groups. These results indicate that chronic treatment with soy isoflavones, at the tested dose did not induce significant changes in the uterus, breast, bone and adipose tissues, suggesting safety in handling without risk for development of cancer.
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