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BACKGROUND AND AIM: Phytoestrogens are traditionally used for cardiovascular risks but direct effects on the ischemic heart remain unclear. Plants with phytoestrogens are used for reducing menopausic symptoms and they could also be cardioprotectives. Here we investigated whether maca (Lepidium meyenii) contains isoflavones and prevents cardiac stunning, in comparison to soy isoflavones. EXPERIMENTAL PROCEDURE: Both products were orally and daily administered to rats during 1 week before exposing isolated hearts to ischemia/reperfusion (I/R). Young male (YM), female (YF) and aged female (AgF) rats treated with maca (MACA, 1 g/kg/day) or soy isoflavones (ISOF, 100 mg/kg/day) were compared to acute daidzein (DAZ, 5 mg/kg i.p.) and non-treated rat groups. Isolated ventricles were perfused inside a calorimeter to simultaneously measure contractile and calorimetrical signals before and during I/R. RESULTS AND CONCLUSIONS: Maca has genistein and daidzein. MACA and ISOF improved the post-ischemic contractile recovery (PICR) and muscle economy (P/Ht) in YM and YF hearts, but not in AgF hearts. DAZ improved PICR and P/Ht more in YM than in YF. The mKATP channels blockade reduced both PICR and P/Ht in DAZ-treated YM hearts, without affecting them in ISOF or MACA-treated YM hearts. In MACA treated YF hearts, the simultaneous blockade of NOS and mKATP channels, or the mNCX blockade reduced cardioprotection. Results show that subacute oral treatment with maca or with soy isoflavones was strongly preventive of cardiac ischemic dysfunction, more than the acute administration of a pure isoflavone (daidzein, genistein). Maca induced synergistic and complex mechanisms which prevented mitochondrial calcium overload.

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AIM: Although soy isoflavones (ISO) have been shown to relief postmenopausal symptoms, it remains inconclusive whether ISO can improve lipid-profile without uterotrophic effects under estrogen-deficiency. Thus, we investigated the effects of ISO on lipid-profile and uterus of ovariectomized (Ovx) rats. MATERIALS AND METHODS: Twenty-five adult rats were Ovx or Sham-operated (Sham) and assigned into five groups: Sham and Ovx groups, administered with vehicle solutions; Ovx-E, treated with 10 µg/kg of 17ß-Estradiol; Ovx-ISO, treated with 200 mg/kg of ISO; Ovx-E + ISO, treated with estradiol + ISO combined. After fifty days of treatments, rats were euthanized and uterine horns were processed for histomorphometry or to collagen fibers and glycosaminoglycans evaluations. Blood samples were collected to evaluate levels of triglycerides, total cholesterol (TC) and its fractions (HDL/VLDL). Data were subjected to statistical analysis (p < .05). RESULTS: Uterus weight was lower in Ovx group than the Sham and Ovx-E groups, whereas it was similar between Ovx and Ovx-ISO groups. Histomorphometry showed atrophic uterus in Ovx and Ovx-ISO groups, whereas uterotrophic effects were noticed in Ovx-E and Ovx-E + ISO groups. Collagen fibers-birefringence was higher in Sham, Ovx, and Ovx-ISO groups than in Ovx-E and Ovx-E + ISO groups. Sulfated glycosaminoglycans content was similar among Sham, Ovx, and Ovx-ISO groups, while it was higher in estrogen-treated groups; total glycosaminoglycans content was similar among groups. TC and HDL was higher in Ovx-ISO group, whereas VLDL and triglycerides levels was higher in Ovx-E + ISO group and similar among other groups. CONCLUSION: Soy isoflavones at 200 mg/kg have slight beneficial effects on lipid-profile without uterotrophic effects in Ovx rats.

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Soybean is one of the most important commodities in the world, being applied in feed crops and food, pharmaceutical industries in different ways. Soy is rich in isoflavones that in aglycone forms have exhibited significant anti-obesity and anti-lipogenic effects. Obesity is a global problem as several diseases have been related to this worldwide epidemic. The aim of this work was to verify the effect of free and immobilized ß-glucosidase, testing Lentikats, and sol-gel as carriers. Moreover, we wanted to examine if the different types of hydrolysis would generate extracts with distinct biological activity concerning lipid accumulation, PPAR-α regulation, and TNF-α, IL-6, and IL-10 concentrations using in vitro assays. Our results show that all formulations of ß-glucosidase could hydrolyze soy isoflavones. Thus, after 24 h of incubation, daidzein content increased 2.6-, 10.8-, and 12.2-fold; and genistein content increased 11.7, 11.4, and 11.4 times with the use of free enzyme, Lentikats®, and sol-gel immobilized enzyme, respectively. Moreover, both methodologies for enzyme immobilization led to promising forms of biocatalysts for application in the production of soy extracts rich in isoflavones aglycones, which are expected to bring about health benefits. A mild lipogenic effect was observed for some concentrations of extracts, as well as a slight inhibition in PPAR-α expression, although no significant differences were noticeable in the cytokines TNF-α, IL-10, and IL-6 as compared with the control.

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The present study aimed to investigate, in in vitro assays, the antilipogenic and antiinflammatory potential as well as the antioxidant capacity of biotransformed soymilk by tannase and ß-glycosidase enzymes. The results showed a significant enhancement of the antioxidant capacity, especially by biotransformed soymilk with free tannase (SFT), corresponding to an increase of 2.3 and 1.25 times by oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays, respectively. The lipid accumulation reduction by 3T3-L1 adipocytes assay was not significant. However, the antiinflammatory responses were expressive. In lipopolysaccharide-stimulated RAW 264.7 macrophages, SFT reduced around 37 times TNF-α expression at the highest tested concentration of the sample. Other inflammatory parameters, as IL-6 and nitric oxide, were no longer detected when the cells were treated with SFT and soymilk with immobilized enzymes, respectively. The biotransformed soy extracts with tannase have great potential to act as a nutraceutical, protecting the cells against oxidative damage and helping maintain health under inflammatory stress. PRACTICAL APPLICATIONS: Soy isoflavones have been associated with several beneficial effects on human health, including inhibition capacity of lipid accumulation in adipocytes, antiinflammatory properties, and antioxidant potential. However, the isoflavones bioavailability differs among their chemical forms, and studies have shown that the higher health benefits are conferred by aglycones and their metabolites, such as equol, compared to the other forms. For this reason, the enrichment of isoflavone aglycones and metabolites in soy-based products has attracted growing attention. The present study was focused on developing a bioprocess able to produce a rich extract with soy isoflavones metabolites, with increased bioactive potential for application as a functional ingredient or a nutraceutical.

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Ovarian aging is characterized by declines in follicular reserve and oocyte quality due, in part, to increased oxidative stress and apoptosis. Soy isoflavones (ISOs) have been shown to improve ovarian lifespan by acting as antioxidant and antiapoptotic agents. We aimed at evaluating whether ISOs could modulate oxidative stress and reduce apoptosis and improve ovarian follicle survival in middle-aged female rats. Twelve ovary-intact female Wistar rats (12-month-old) were divided into groups: control (CTRL) and ISO, daily treated by gavage with vehicle or soy-ISO extract (150 mg/kg b.w), respectively. After 8 weeks, rats were euthanized and their ovaries removed for histomorphometric (% follicles) and apoptosis (cleaved-caspase-3/BCL2 immunostaining) evaluations, or subjected to biochemical assays to survey reactive oxygen species (ROS) and lipid peroxidation levels and total antioxidant capacity (TAC). The frequency of atretic follicles and number of cleaved-caspase-3-positive cells, as well as the ROS and lipid peroxidation levels, were significantly lower in ISO group compared to CTRL. A significantly higher number of BCL2-positive cells and TAC levels were also observed in ISO group. In conclusion, soy ISOs could decrease follicular atresia, apoptosis and oxidative stress, as well as increase the TAC in ovaries of female rats.

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Objetivo: Diminuição das células granulares do túbulo contorcido granular e dos ácinos ocorre nas glândulas submandibulares de ratas fêmeas ovariectomizadas, enquanto que nas ratas submetidas a reposição hormonal e fitoterapia com isoflavona da soja, este efeito é revertido. Este estudo tem como objetivo elucidar os mecanismos pelo qual estas alterações ocorrem. Material e Métodos: 84 ratas foram ovariectomizadas e 21 foram sham-operatadas. As ratas ovariectomizadas foram aleatoriamente subdivididas e receberam administração oral dos seguintes medicamentos: 17 ß-estradiol (OVX-E; n=21), 15 mg/ kg/day do extrato de isoflavona da soja (OVX-I; n=21), 17 ß-estradiol + extrato de isoflavona da soja (OVX-A; n=21); e água como placebo (OVX; n=21). As ratas foram eutanasiadas 3, 5 e 8 semanas após a ovariectomia. As glândulas submandibulares foram submetidas a análise histológica por meio do processamento histológico de coloração com HE e imunohistoquímica utilizando o complexo peroxidase-biotina-streptavidina. A área celular e a expressão do antígeno de proliferação celular nuclear e receptor ß estrogênico foram avaliados. Resultados: Os resultados foram estatisticamente analisados por meio do teste ANOVA e Tukey. Foi observada diminuição na área de células GCT cells no grupo OVX, em contraste com o aumento no grupoe OVX-E. PCNA nas células acinares e receptores de estrógeno estavam aumentados no grupo OVX-I. Conclusão: A castração exerce um efeito indutivo imediato no volume das células GCT. Estrógeno, isoflavona da soja e sua combinação têm diferentes mecanismos de ação sobre a homeostase da glândula. Estrógeno causa um aumento da área de células GCT, enquanto a isoflavona aumenta a proliferação celular e a expressão do receptor-ß de estrógeno. A associação destes não mostrou aumento adicional nos efeitos estudados (AU)

Objective: A decrease in granular convoluted tubule (GCT) cells and acini occurs in the submandibular glands of castrated female rats, while in rats submitted to hormone replacement and phytotherapy with soy isoflavones, this effect is reversed. This study aimed to elucidate the mechanisms through which these changes occur. Material and Methods: Rats (n=84) were ovariectomized and 21 were sham-operated. Ovariectomized rats were randomly subdivided and orally administered the following: 17 ß-estradiol (OVX-E; n=21), 15 mg/kg/day of soy isoflavone extract (OVX-I; n=21), 17 ß-estradiol + soy isoflavone extract (OVX-A; n=21); and water as placebo (OVX; n=21). The rats were euthanized three, five and eight weeks after ovariectomy. The submandibular salivary glands were submitted to histological processing with HE stain and immunohistochemistry was performed using the streptavidin-biotinperoxidase complex. The cell area and the expression of proliferating cell nuclear antigen and estrogen receptor ß were evaluated. Results: The results were statistically analyzed by ANOVA and Tukey test. A decrease in the area of GCT cells in the OVX, was observed, in contrast with an increase in the OVX-E. PCNA in the acinar cells and estrogen receptors were elevated in the OVX-I group. Conclusion: Castration exerts an immediate reductive effect on the volume of GCT cells. Estrogens, soy isoflavones and their combination have different mechanisms of action on the homeostasis of the gland. Estrogens cause an increase in GCT cells area, while isoflavones enhance cell proliferation and the expression of estrogen receptor-ß. Their association showed no additional increase in the effect studied. (AU)

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The aim of this paper was to evaluate the effect of the thermal treatment of whole soybean flour (WSF) on the conversion of isoflavones and the inactivation of trypsin inhibitors. Soybeans were ground and whole soybean flour was obtained and subjected to heat treatment in an oven for 10, 15 and 20min at 100, 150 and 200°C according to a 3(2) experimental design. The response functions were taken to be the contents of different isoflavone forms and the residual activity of trypsin inhibitors. The thermal treatment in the oven altered the content and profile of the different isoflavones forms. At 200°C for 20min, there was a higher conversion of malonylglycosides to acetylglycosides, ß-glycosides and aglycones and a significant reduction in the activity of trypsin inhibitors. Mathematical models were established to estimate the process parameters in obtaining the WSF with isoflavone conversions and reductions in trypsin inhibitor activity.

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Las isoflavonas de la soja son metabolitos secundarios conocidos como fitoestrógenos por su similitud estructural con el 17b-estradiol. La daidzeina y la genisteina son las principales isoflavonas de la soja. Debido a su capacidad de unión a los receptores de estrógeno (RE) >son consideradas moduladores selectivos de los receptores de estrógenos (MSRE). El consumo dietario de isoflavonas es relacionado con la disminución de los síntomas de la menopausia, prevención de enfermedades cardiovasculares y de otras enfermedades crónicas como la diabetes mellitus. Las isoflavonas han sido propuestas también para el tratamiento de algunos tipos de cáncer y la prevención de la osteoporosis; sin embargo, existe gran controversia sobre los posibles efectos estrogénicos en niños púberes y prepúberes alimentados con fórmulas a base de proteína de soja. El objetivo de este trabajo es presentar una revisión sistemática de la química de las isoflavonas de la soja y sus efectos sobre la salud del hueso en adultos y niños.

The soy isoflavones are secondary metabolites known as phytoestrogens because of its structural similarity to 17b-estradiol. Genistein and Daidzein are the main soy isoflavones. Due their binding ability to estrogen receptors (ER) they are considered as selective estrogen receptor modulators (SERM). The dietary intake of isoflavones has been associated with decreasing menopause symptoms, prevention of cardiovascular disease and some chronic diseases such as diabetes mellitus. Also, the isoflavones have been proposed for the treatment of certain kind of cancer and osteoporosis prevention, but there is a lot of controversy about the possible estrogenic effects in pubertal and prepubertal children who have been fed with soy protein-based formulas. The aim of this research is to present a systematic review of the soy isoflavone chemistry and their effects on bone health in adults and children.