Research Update:Genistein:4',5,7-Trihydroxyisoflavone.:Introduction and Its Benefit Applications.Genisteol,Genisterin,Prunetol,Sophoricol,isoflavone,flavonoids,phytoestrogens,antioxidantm,anticancer.Serie No.:Pure05.Pure Phytochemical Series.MDidea Extracts Professional.

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Research Update:Genistein:4',5,7-Trihydroxyisoflavone:

A study on isoflavones intake from soy foods and perimenstrual symptoms.:Taehan Kanho Hakhoe Chi. 2007 Apr;37(3):276-85. Korean.Kim HW, Khil JM.Department of Nursing, College of Medicine, Kwandong University, Korea. hwkim@kd.ac.kr.

PURPOSE: This study was conducted to explore the relationship between isoflavones intake from soy foods and perimenstrual symptoms among women. METHODS: The research design was a cross sectional study. Subjects consisted of 245 women living in Korea, aged 19-49 years. The measurement tools were MDQ and FFQ. RESULTS: Frequently consumed soy isoflavones foods were rice with soybeans, soybean paste stew, and soy paste with tofu. The amounts of soy isoflavones foods consumed in order from highest to lowest were rice with soybeans, soybean paste stew, seasoned soybean sprouts, and soy paste with tofu. Subjects were divided into three groups by isoflavones intake levels; the small intake group, moderate intake group, and large intake group. There were significant differences in some menstrual symptoms, and postmenstrual symptoms by isoflavones intake levels. In general, the moderate isoflavones intake group showed lower scores in some menstrual symptoms and postmenstrual periods compared to the small and large intake groups. CONCLUSIONS: These results suggest some positive health effects of isoflavones from soy foods on perimenstrual symptoms. More accurate, objective measurement needs to be applied and more investigation of soy isoflavones effects on many aspects of women's health need to be done in a future study.

Soy isoflavone intake and estrogen excretion patterns in young women: effect of probiotic administration.:In Vivo. 2007 May-Jun;21(3):507-12.Cohen LA, Crespin JS, Wolper C, Zang EA, Pittman B, Zhao Z, Holt PR.Institute for Cancer Prevention, Valhalla, NY, USA. Lac65@earthlink.net

BACKGROUND: Soy isoflavones may lower breast cancer risk through altered hepatic estrogen metabolism, leading to increased urinary excretion ratios of 2-hydroxyestrone (20HE1) to 16a-hydroxyestrone (16alphaOHE1). MATERIALS AND METHODS: Urinary excretion of 20HE1/16alphaOHE1 was measured in 36 healthy, pre-menstrual women before and after ingestion of a soy-protein formula containing 120 mg of isoflavone daily for one month. Since isoflavone absorption and metabolism depends on intestinal bacteria, effects of co-administration of Lactobacillus GG (2 x 10(12)) on estrogen ratios and isoflavone excretion were studied. Urinary isoflavone excretion measurements assessed compliance. RESULTS: Soy isoflavone ingestion induced quantitative differences in urinary excretion of estrogen metabolites and isoflavones but failed to alter 20HE1/16alphaOHE1 ratios. Co-administration of Lactobacillus GG with soy reduced excretion of total and individual isoflavones by 40% (p=0.08), without altering 2OHE1/16alphaOHE1 ratios. CONCLUSION: Isoflavone-rich soy protein administration alone, or with probiotic supplement, did not alter urinary excretion of estrogen metabolites in premenopausal women. However, adding concentrated probiotics may alter isoflavone bioavailability.

Flavonoid profile in soybeans by high-performance liquid chromatography/tandem mass spectrometry.:Rapid Commun Mass Spectrom. 2007;21(14):2177-87.Cavaliere C, Cucci F, Foglia P, Guarino C, Samperi R, Lagan¨¤ A.Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Roma, Italy.

Flavonoid profiling of a soybean sample has been performed by liquid chromatography/positive electrospray tandem mass spectrometry (LC/ESI(+)-MS/MS) using a quadrupole-linear ion trap (QLIT) instrument with an information-dependent data acquisition (IDA) protocol that looped, in a single run, an enhanced MS scan and an enhanced product ion scan. As compromise between time and obtainable information, spectra acquisition was split into two distinct runs: 220-450 Th and 400-800 Th, respectively. The isoflavones daidzein and genistein were identified as aglycones, monoglycosides, diglycosides, triglycosides, acetylglycosides, malonylglycosides, malonyl diglycosides, and dimalonyl diglycosides, whereas glycitein triglycosides, acetylglycosides, and dimalonyl diglycosides were not detected. Also kaempferol di- and triglycosides, malonylglycosides and malonyl diglycosides, previously reported in soy leaves and pods, and four naringenin malonylglycosides were identified.

A UDP-glucose:isoflavone 7-O-glucosyltransferase from the roots of soybean (Glycine max) seedlings: Purification, gene cloning, phylogenetics, and an implication for an alternative strategy of enzyme catalysis.:J Biol Chem. 2007 Jun 11;Noguchi A, Saito A, Homma Y, Nakao M, Sasaki N, Nishino T, Takahashi S, Nakayama T.Dept. Biomol. Engin., Grad. Sch. Engin., Tohoku Univ., Sendai, Miyagi 980-8579.

Isoflavones, a class of flavonoids, play very important roles in plant-microbe interactions in certain legumes, such as soybeans (Glycine max (L.) Merr.). UDP-glucose:isoflavone 7-O-glucosyltransferase of G. max (GmIF7GT) is a key enzyme in the synthesis of isoflavone conjugates, which accumulate in large amounts in vacuoles and serve as an isoflavonoid pool that allows for interaction with microorganisms. In this study, the 14,000-fold purification of GmIF7GT from the roots of G. max seedlings was accomplished. The purified enzyme was a monomeric protein of 46 kDa, catalyzing regiospecific glucosyl transfer from UDP-glucose to isoflavones to produce isoflavone 7-O-beta-D-glucosides (k(cat), 0.74 sec(-1); K(m) for genistein, 3.6 muM; K(m) for UDP-glucose, 190 muM). The GmIF7GT cDNA was isolated based on the amino acid sequence of the purified enzyme. A phylogenetic analysis showed that GmIF7GT is a novel member of the glycosyltransferase family 1 and is distantly related to UDP-glucose:isoflavonoid 7-O-glucosyltransferase of Glycyrrhiza echinata. Unexpectedly, the purified enzyme was devoid of the N-terminal 49-residue segment, thus lacking the histidine residue corresponding to the proposed catalytic residue of glycosyltransferases from Medicago truncatula (UGT71G1) and Vitis vinifera (VvGT1). The results of kinetic studies of site-directed mutants of GmIF7GT showed that both His-15 and Asp-125, which correspond to the catalytic residues of UGT71G1 and VvGT1, are unimportant for GmIF7GT activity. The results also suggested that an acidic residue at position 392 is very important for primary catalysis of GmIF7GT. All of these results led to the proposal that GmIF7GT utilizes a strategy of catalysis that is distinct from those proposed for UGT71G1 and VvGT1.

Effect of soy nuts on blood pressure and lipid levels in hypertensive, prehypertensive, and normotensive postmenopausal women.:Arch Intern Med. 2007 May 28;167(10):1060-7.Welty FK, Lee KS, Lew NS, Zhou JR.Division of Cardiology, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA. fwelty@bidmc.harvard.edu

BACKGROUND: Epidemiologic studies suggest a low incidence of cardiovascular disease in populations that consume dietary soy. For people aged 40 to 70 years, each increment of 20 mm Hg in systolic blood pressure (BP) or 10 mm Hg in diastolic BP doubles the risk of cardiovascular disease for BPs of 115/75 to 185/115 mm Hg. METHODS: To determine the effect of soy nuts on systolic and diastolic BP and lipid levels, 60 healthy postmenopausal women were randomized in a crossover design to a Therapeutic Lifestyle Changes (TLC) diet alone and a TLC diet of similar energy, fat, and protein content in which soy nuts (containing 25 g of soy protein and 101 mg of aglycone isoflavones) replaced 25 g of non-soy protein. Each diet was followed for 8 weeks. RESULTS: Compared with the TLC diet alone, the TLC diet plus soy nuts lowered systolic and diastolic BP 9.9% and 6.8%, respectively, in hypertensive women (systolic BP> or =140 mm Hg) and 5.2% and 2.9%, respectively, in normotensive women (systolic BP<120 mm Hg). Further subdivision of normotensive women revealed that systolic and diastolic BPs were lowered 5.5% and 2.7%, respectively, in prehypertensive women (systolic BP of 120-139 mm Hg) and 4.5% and 3.0%, respectively, in normotensive women. Soy nut supplementation lowered low-density lipoprotein cholesterol and apolipoprotein B levels 11% and 8% (P = .04 for both), respectively, in hypertensive women but had no effect in normotensive women. CONCLUSIONS: Substituting soy nuts for nonsoy protein in a TLC diet improves BP and low-density lipoprotein cholesterol levels in hypertensive women and BP in normotensive postmenopausal women. These findings may explain a cardioprotective effect of soy.

Effect of prenatal exposure to isoflavones on bone metabolism in mice at adulthood.:Pediatr Res. 2007 Apr;61(4):438-43.Ward WE, Piekarz AV.Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Canada. wendy.ward@utoronto.ca

Early postnatal exposure to genistein resulted in improved bone health at early adulthood in mice. The objective of the present study was to determine whether in utero exposure to isoflavones also has a positive effect on bone health, resulting in higher bone mineral density (BMD) and greater resistance to fracture at adulthood. Pregnant mice received daily subcutaneous injections of genistein (3.75 mg), daidzein (3.75 mg), genistein (3.75 mg) + daidzein (3.75 mg), or vehicle from d 9 to 21 of pregnancy. At birth, offspring (n = 12/group/gender) remained with their respective mother and were weaned at postnatal age of 21 d and fed control diet, devoid of isoflavones, until 4 mo of age, at which time tissues were collected. There was an overall effect of treatment on femur BMD, which was higher (p<0.001) among control and genistein groups compared with daidzein and genistein + daidzein groups. Treatment did not have a significant effect on femur peak load. Among females, daidzein resulted in a lower (p=0.02) BMD of lumbar vertebra (LV) 1-4 than all other groups however peak load of LV4 did not differ due to treatment or gender. In conclusion, in utero exposure to isoflavones did not result in functional benefits to bone at young adulthood.

Dietary soy protein containing isoflavonoids does not adversely affect the reproductive tract of male cynomolgus macaques (Macaca fascicularis).:J Nutr. 2007 Jun;137(6):1390-4.Perry DL, Spedick JM, McCoy TP, Adams MR, Franke AA, Cline JM.Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA. dlperry@wfubmc.edu

Short-term dietary studies of soy-protein-derived isoflavonoids, using rodent and nonhuman primate models, have documented variable effects on the reproductive tract. Long-term effects of dietary soy and/or isoflavonoids on the reproductive tract of nonhuman primates have not been determined. The objective of this study was to assess the effects of long-term consumption of dietary soy isoflavonoids on histomorphology of the mammary glands and prostate gland, testis, and sperm counts in adult male cynomolgus macaques. Ninety-one adult male cynomolgus macaques (Macaca fascicularis) were fed diets for 3 y differing only in protein source: 1) a soy-free, casein-lactalbumin-based diet or 2) a low-soy isoflavonoid diet ( approximately 6 mg . kg(-1) . d(-1)) or 3) a high-soy isoflavonoid diet ( approximately 12 mg . kg(-1) . d(-1)). Serum isoflavonoids were measured by liquid chromatographic-photodiode array electrospray MS. Mammary gland, prostate gland, and testes were obtained at postmortem and evaluated histopathologically and histomorphometrically. Epididymal and testicular sperm counts were performed. Serum isoflavonoid concentrations at 4 h postfeeding differed among all groups (P < 0.001) and were (means +/- SEM) 67 +/- 23 (soy-free diet), 799 +/- 44 (low-soy isoflavonoid diet), and 1458 +/- 80 nmol . L(-1) (high-soy isoflavonoid diet). Diet did not alter serum estradiol and testosterone concentrations or epididymal and testicular sperm counts. Organ weights and histologic indices did not differ among treatment groups. Mammary gland histopathologic and histomorphometric analysis revealed no abnormalities and no indication of gynecomastia. We found no evidence of an adverse effect of soy isoflavonoids at physiologically relevant doses within the reproductive organs of adult male macaques.

Proteome analysis suggests that mitochondrial dysfunction in stressed endothelial cells is reversed by a soy extract and isolated isoflavones.:J Proteome Res. 2007 Jun;6(6):2132-42. Epub 2007 May 16.Fuchs D, Dirscherl B, Schroot JH, Daniel H, Wenzel U.Department of Food and Nutrition, Molecular Nutrition Unit, Technical University of Munich, Am Forum 5, D-85350 Freising, Germany.

Apoptosis is a driving force in atherosclerosis development. A soy extract or a combination of the soy isoflavones genistein and daidzein inhibited apoptosis induced by oxidized LDL in endothelial cells. Proteome analysis revealed that the LDL-induced alterations of numerous proteins were reversed by the extract and the genistein/daidzein mixture but only three protein entities, all functionally linked to mitochondrial dysfunction, were regulated in common by both treatments.

Effect of soy isoflavones on endometriosis: interaction with estrogen receptor 2 gene polymorphism.:Epidemiology. 2007 May;18(3):402-8.

BACKGROUND: Progression of endometriosis is considered estrogen-dependent. Dietary soy isoflavones may affect the risk of endometriosis, and polymorphisms in estrogen receptor genes may modify this association. We examined associations among soy isoflavone intake, estrogen receptor 2 (ESR2) gene polymorphisms and risk of endometriosis. METHODS: We recruited women age 20-45 years old who had consulted a university hospital for infertility in 1999 or 2000. A total of 138 eligible women were diagnosed laparoscopically and classified into 3 subgroups: control (no endometriosis), early endometriosis (stage I-II) and advanced endometriosis (stage III-IV). We measured urinary levels of genistein and daidzein as markers for dietary intake of soy isoflavones, and genotyped ESR2 gene RsaI polymorphisms. RESULTS: Higher levels of urinary genistein and daidzein were associated with decreased risk of advanced endometriosis (P for trend = 0.01 and 0.06, respectively) but not early endometriosis. For advanced endometriosis, the adjusted odds ratio for the highest quartile group was 0.21 (95% confidence interval = 0.06-0.76) for genistein and 0.29 (0.08-1.03) for daidzein, when compared with the lowest group. Inverse associations were also noted between urinary isoflavones and the severity of endometriosis (P for trend = 0.01 for genistein and 0.07 for daidzein). For advanced endometriosis, ESR2 gene RsaI polymorphism appeared to modify the effects of genistein (P for interaction = 0.03). CONCLUSIONS: Dietary isoflavones may reduce the risk of endometriosis among women.

The soy effect in the disease models of nonbacterial prostatitis and obstructive voiding.:Exp Biol Med (Maywood). 2007 May;232(5):674-81.Yatkin E, Streng T, Kauppila ML, Bernoulli J, Saarinen N, Santti R.Department of Anatomy, Institute of Biomedicine, University of Turku, Turku, Finland. emrah.yatkin@utu.fi

The goal of this study was to improve the understanding of the potential significance of dietary soy for human health by investigating its effects in the animal models of nonbacterial prostatitis and urethral obstruction. Nonbacterial prostatitis was induced in adult Noble rats with the combined treatment of testosterone and 17beta-estradiol. The inflammatory foci categorized into three forms were counted and correlated with expression of an estrogen-responsive gene, progesterone receptor (PR), in the dorsolateral lobes of the rats on soy (+) and soy (-) diets. Development of obstructive voiding after neonatal estrogenization of Noble rats (NeoDES rats) was followed with urodynamic measurements in rats on soy (+) and soy (-) diets. The amounts of genistein and daidzein, two major soy-derived isoflavones, were measured in the urine of Noble rats by the high-performance liquid chromatography-photodiodearray method. Dietary soy decreased the total number of inflammatory foci while no demonstrable effects were seen on the cellular composition of the infiltrates. Soy did not increase the weights of the pituitary gland, testes, or sex accessory glands, but it did increase the number of PR-positive epithelial cells in the dorsolateral prostate. It also decreased the bladder pressures in NeoDES rats but did not increase the flow rates. The soy effects may be mediated by the strong estrogen influence involved in the animal models. Dietary soy had anti-inflammatory effects in the prostate but only marginal effects on the development of obstructive voiding in Noble rats. The anti-inflammatory effects of soy may contribute to the lower prevalence of prostatitis-like symptoms and the historically lower risk of benign prostatic hyperplasia; however, no evidence was found that regular consumption of soy influences the age-related development of lower urinary tract symptoms or decline of flow rate.

Improvement of immune cell functions in aged mice treated for five weeks with soybean isoflavones.:Ann N Y Acad Sci. 2007 Apr;1100:497-504.Baeza I, de Castro NM, Alvarado C, Alvarez P, Arranz L, Bay¨®n J, de la Fuente M.Department of Animal Physiology, Faculty of Biological Sciences, Complutense University, 28040 Madrid, Spain. mondelaf@bio.ucm.es.

Aging is associated with an impaired immune system as well as with a decline of several hormones, such as estrogens. Dietary phytoestrogens have been proposed as an alternative to hormone replacement therapy. The beneficial action of soybean compounds is probably due to isoflavones, whose role as immunomodulators has been investigated with increasing interest. The aim of the present work was to study whether a 5-week administration of a diet enriched in soybean isoflavones and green tea could influence the immune function of mice that were sham-operated or ovariectomized. Natural killer activity (NK) and lymphoproliferation in response to the mitogens concanavaline A (Con A) and lipopolysaccharide (LPS), were studied in peritoneal leukocytes. Both treatments with soybean or green tea plus soybean were highly effective in improving these immune parameters with respect to control groups. Since the immune system is a marker of health and a predictor of longevity, an adequate treatment with isoflavones could be useful in slowing down the effects of the aging process through an improvement in the two relevant immune functions studied.

Chromatographic and electrophoretic approaches for the analysis of protein quality of soy beverages.:J Sep Sci. 2007 Mar;30(4):502-7.Amigo-Benavent M, Villamiel M, del Castillo MD.Instituto de Fermentaciones Industriales, CSIC, Madrid, Spain.

Furosine, generated by acid hydrolysis of fructosyllysine, an early Maillard reaction product, is a highly valuable indicator of food quality and, more specifically, of food protein quality. Ion pair RP-HPLC and CZE techniques were employed to determine furosine content in beverages based on soymilk (n = 15) and cow's milk supplemented with soy isoflavones (n = 1). The levels of furosine found in the samples ranged from 25.55 +/- 0.18 to 170.72 +/- 10.4 mg/100 g of protein by HPLC and from 28.67 +/- 1.84 to 161.25 +/- 5.78 mg/100 g of protein by CZE. Results obtained by both analytical techniques do not differ significantly (p > 0.05), confirming their feasibility for furosine analysis in soy-based products.

The association between soy nut consumption and decreased menopausal symptoms.:J Womens Health (Larchmt). 2007 Apr;16(3):361-9.Welty FK, Lee KS, Lew NS, Nasca M, Zhou JR.Division of Cardiology, Beth Deaconess Medical Center, Boston, Massachusetts 02215, USA. fwelty@bidmc.harvard.edu

BACKGROUND: Epidemiological studies suggest a low incidence of hot flashes in populations that consume dietary soy. The present study examined the effect of soy nuts on hot flashes and menopausal symptoms. METHODS: Sixty healthy postmenopausal women were randomized in a crossover design to a therapeutic lifestyle changes (TLC) diet alone and a TLC diet of similar energy, fat, and protein content in which one-half cup soy nuts divided into three or four portions spaced throughout the day (containing 25 g soy protein and 101 mg aglycone isoflavones) replaced 25 g of nonsoy protein. During each 8-week diet period, subjects recorded the number of hot flashes and amount of exercise daily. At the end of each 8-week diet period, subjects filled out the menopausal symptom quality of life questionnaire. RESULTS: Compared to the TLC diet alone, the TLC diet plus soy nuts was associated with a 45% decrease in hot flashes (7.5 +/- 3.6 vs. 4.1 +/- 2.6 hot flashes day, respectively, p < 0.001) in women with >4.5 hot flashes/day at baseline and 41% in those with

The effects of soy milk and isoflavone supplements on cognitive performance in healthy, postmenopausal women.:J Nutr Health Aging. 2007 Mar-Apr;11(2):155-64.Fournier LR, Ryan Borchers TA, Robison LM, Wiediger M, Park JS, Chew BP, McGuire MK, Sclar DA, Skaer TL, Beerman KA.Department of Psychology, Washington State University, Pullman, WA 99164-4820, USA. Fournier@wsunix.wsu.edu

RATIONALE: The decline in estrogen concentrations in women after menopause can contribute to health related changes including impairments in cognition, especially memory. Because of the health concerns related to hormone replacement therapy (HRT), alternative approaches to treat menopausal symptoms, such as nutritional supplements and/or diet containing isoflavones, are of interest. OBJECTIVES: This study investigated whether soy isoflavones (soy milk and supplement) could improve cognitive functioning in healthy, postmenopausal women. PARTICIPANTS, INTERVENTION AND DESIGN: A total of 79 postmenopausal women, 48-65 years of age, completed a double-blind, placebo-controlled trial in which they were randomly assigned to one of three experimental groups: cow's milk and a placebo supplement (control); soy milk and placebo supplement (soy milk, 72 mg isoflavones/day); or cow's milk and isoflavone supplement (isoflavone supplement, 70 mg isoflavones/day). MEASUREMENTS: Cognitive functioning was assessed using various cognitive tasks before the intervention (baseline) and after the intervention (test). RESULTS: In contrast to predictions, soy isoflavones did not improve selective attention (Stroop task), visual long-term memory (pattern recognition), short-term visuospatial memory (Benton Visual Retention Test), or visuo-spatial working memory (color match task). Also, the soy milk group showed a decline in verbal working memory (Digit Ordering Task) compared to the soy supplement and control groups. CONCLUSION: Soy isoflavones consumed as a food or supplement over a 16-week period did not improve or appreciably affect cognitive functioning in healthy, postmenopausal women.

Reproductive safety studies with genistein in rats.:Food Chem Toxicol. 2007 Aug;45(8):1319-32. Epub 2007 Jan 21.McClain RM, Wolz E, Davidovich A, Edwards J, Bausch J.McClain Associates, Toxicology Department, 10 Powder Horn Terr, Randolph, NJ 07869, USA.

Genistein is a phytoestrogen that occurs naturally in the diet and is found in a wide variety of plant-derived foods especially in soybeans and soy-based foods. There is wide spread interest in genistein and related phytoestrogens as chemopreventive agents for a variety of human diseases and cancers based on epidemiologic evidence of reduced cancer rates in populations with a high intake of soy. Soy, and hence its constituents, such as genistein, have been consumed at high levels in several Asian populations for many centuries without any apparent adverse effects and to the contrary, many health benefits have been associated with the ingestion of soy based foods. Concern has been raised, however, of potential adverse effects due to the estrogenic and other activities of the isoflavones and thus a comprehensive series of safety studies was performed with genistein. To assess the teratogenic and fetal toxic potential of genistein, several studies were conducted. Genistein was tested in an in vitro rat whole embryo culture assay (WEC), which is a preliminary screen, for fetotoxic and teratogenic potential, over a concentration range of from 1 to 100mug/mL. Treatment related anomalies were observed at concentrations of 10mug and at 100mug/mL, all embryos were malformed. Two in vivo embryo fetal developmental safety studies were conducted with genistein by oral administration (gavage and dietary admix) in which there was no evidence for a teratogenic effect. In an oral (gavage) embryonic and fetal development pilot study, genistein was administered to rats at dose levels of 0, 20, 150 and 1000mg/kg/day from days 6-20 of gestation to females that were allowed to litter and rear their offspring up to day 7 of lactation. A slight maternal toxicity at 1000mg/kg/day was observed as indicated by decreased body weight and food consumption and at this dose, adverse effects in the pups were observed including increased pup mortality, poor general condition, reduced pup body weights, and reduced pup milk uptake. At the high dose of 1000mg/kg, no external malformations were noted, however some minor visceral and skeletal variations were observed. At the low dose of 20mg/kg/day, an increased mortality, reduced milk uptake, a decreased % male sex ratio, and decreased body weights during lactation were observed. Due to lack of effects at the mid dose and the small number of animals, a relationship to treatment was considered unlikely. In an oral (dietary admix) Prenatal developmental safety study, genistein was administered to rats at dose levels of 0, 5, 50, 100 and 500mg/kg/day from day 5-21 of gestation. At 500mg/kg, maternal body weight and food consumption were markedly reduced. The incidence of resorptions was markedly increased with a corresponding decrease in the number of live fetuses per dam. Fetal body weights were also reduced. No treatment-related teratogenic effects were noted during external, visceral and skeletal examination of fetuses or in body weight normalized anogenital distance. On the basis of these studies, it is concluded that genistein has no teratogenic potential in vivo at very high doses of up to 1000mg/kg/day by oral gavage in the embryo-fetal toxicity pilot study or up to 500mg/kg/day by dietary admix in the Prenatal developmental study even though these doses were maternally toxic and fetal-toxic. In vitro, genistein had teratogenic potential at high concentrations in the WEC screening assay, however this was not predictive of the in vivo findings. On the basis of the definitive Prenatal development study, the NOAEL for maternal toxicity and adverse effects on embryonic development was considered to be 100mg/kg/day when administered orally by dietary admix.

Optimization of a rapid microwave assisted extraction method for the liquid chromatography-electrospray-tandem mass spectrometry determination of isoflavonoid aglycones in soybeans.:J Chromatogr A. 2007 Jun 8;1152(1-2):274-9. Epub 2007 Apr 4.Careri M, Corradini C, Elviri L, Mangia A.Dipartimento di Chimica Generale ed Inorganica, Chimica Analitica, Chimica Fisica, Universit¨¤ degli Studi di Parma, Parco Area delle Scienze 17/A, 43100 Parma, Italy. careri@unipr.it

A very fast chromatographic separation of isoflavonoids genistein, daidzein, formononetin and biochanin A was developed on a C18 high-speed column under isocratic conditions. The method was validated in terms of detection limits, quantitation limits (LOQs), linearity and precision. LOQs in 0.04-0.2 microg/g range were calculated, making feasible the determination of these compounds of nutritional concern at trace levels. Good linearity was demonstrated over three concentration orders of magnitude for each analyte (r2 0.990-1.000). The intra-day and inter-day repeatability was evaluated in terms of relative standard deviation (RSD%) at two concentration levels for each analyte (RSD% <9%). An optimization strategy was adopted to find the best conditions for the extraction of isoflavonoid aglycones from yellow soybeans using microwave-assisted extraction. The most relevant parameters resulted to be the microwave power, the extraction time and the acid concentration, optimal values being 600 W, 1 min and 12 M, respectively. When performing sample treatment on a fortified soybean sample, high recovery percentage was obtained for both compounds (94+/-8% for daidzein and 97+/-5% (n = 4) for genistein). The concentration level at which daidzein and genistein were found in the soybean sample were 1.21+/-0.15 mg/g and 2.38+/-0.09 mg/g (n=4), respectively.

Soy isoflavones lower serum total and LDL cholesterol in humans: a meta-analysis of 11 randomized controlled trials.:Am J Clin Nutr. 2007 Apr;85(4):1148-56.

BACKGROUND: Clinical trials have reported the cholesterol-lowering effects of soy protein intake, but the components responsible are not known. OBJECTIVE: This meta-analysis was primarily conducted to evaluate the precise effects of soy isoflavones on lipid profiles. The effects of soy protein that contains enriched and depleted isoflavones were also examined. DESIGN: PUBMED was searched for English-language reports of randomized controlled trials published from 1990 to 2006 that described the effects of soy protein intake in humans. Eleven studies were selected for the meta-analysis. RESULTS: Soy isoflavones significantly decreased serum total cholesterol by 0.10 mmol/L (3.9 mg/dL or 1.77%; P = 0.02) and LDL cholesterol by 0.13 mmol/L (5.0 mg/dL or 3.58%; P < 0.0001); no significant changes in HDL cholesterol and triacylglycerol were found. Isoflavone-depleted soy protein significantly decreased LDL cholesterol by 0.10 mmol/L (3.9 mg/dL or 2.77%; P = 0.03). Soy protein that contained enriched isoflavones significantly decreased LDL cholesterol by 0.18 mmol/L (7.0 mg/dL or 4.98%; P < 0.0001) and significantly increased HDL cholesterol by 0.04 mmol/L (1.6 mg/dL or 3.00%; P = 0.05). The reductions in LDL cholesterol were larger in the hypercholesterolemic subcategory than in the normocholesterolemic subcategory, but no significant linear correlations were observed between reductions and the starting values. No significant linear correlations were found between reductions in LDL cholesterol and soy protein ingestion or isoflavone intakes. CONCLUSIONS: Soy isoflavones significantly reduced serum total and LDL cholesterol but did not change HDL cholesterol and triacylglycerol. Soy protein that contained enriched or depleted isoflavones also significantly improved lipid profiles. Reductions in LDL cholesterol were larger in hypercholesterolemic than in normocholesterolemic subjects.

Isoflavonoid glucosides are deconjugated and absorbed in the small intestine of human subjects with ileostomies.:Am J Clin Nutr. 2007 Apr;85(4):1050-6.Walsh KR, Haak SJ, Bohn T, Tian Q, Schwartz SJ, Failla ML.Interdisciplinary PhD Program in Nutrition, The Ohio State University, Columbus, OH, USA.

BACKGROUND: Although soy isoflavonoids have a number of health-promoting benefits, information concerning the sites of their absorption and metabolism in humans remains limited. Isoflavonoid absorption from the gut requires deconjugation of glucosides to aglycones. OBJECTIVE: The objective was to investigate the role of the small intestine in isoflavonoid absorption and metabolism in humans. DESIGN: Human subjects with fully functional gastrointestinal tracts (n = 6) and ileostomy subjects (n = 6) were fed a single soy meal containing 64.8 mg isoflavonoid aglycone equivalents (95% as glucosides). Metabolism of isoflavonoids in the upper gastrointestinal tract was examined by analyzing ileal effluent from ileostomy subjects, and absorption was assessed indirectly by quantifying isoflavonoids and several metabolites in 24-h urine pools. RESULTS: Chyme contained 36.7% of ingested isoflavonoid aglycone equivalents, primarily (95.8%) as aglycones. Qualitative profiles (x +/- SEM) of isoflavonoid excretion in urine (daidzein > glycitein > genistein) and the quantity of isoflavonoid equivalents were not significantly different between the control (18.4 +/- 2.2 mg) and ileostomy (13.5 +/- 3.2 mg) subjects. Dihydrodaidzein was present in the urine of all subjects, although the amount excreted by ileostomy subjects was less than that excreted by the control subjects. The percentage of producers and mean quantities of dihydrogenistein, equol, and O-desmethylangolensin in the urine of ileostomy subjects also were lower than those of control subjects. CONCLUSIONS: Ileostomy subjects efficiently deglycosylate isoflavonoid glucosides in the small intestine and appear to absorb aglycones with an efficiency comparable with that of control subjects. However, the production of microbial metabolites of isoflavonoids is limited in ileostomy subjects.

Possible link between NO concentrations and COX-2 expression in systems treated with soy-isoflavones.:Ann N Y Acad Sci. 2007 Jan;1095:564-73.Shin JI, Lee YK, Kim YM, Hwang JT, Park OJ.Department of Food and Nutrition, Hannam University, Daejeon 306-791, Korea.

The production of nitric oxide (NO) emerges as an essential determinant in auto- and paracrine signaling. NO is known to be generated under inflammatory conditions, carcinogenesis, and circulatory shock. The large amount of NO produced in response to cytokines plays an important role in inflammatory conditions. Cyclooxygenase (COX), the central enzyme in prostanoid biosynthesis, is involved in the first step of prostanoid synthesis from arachidonic acid. The reported studies to evaluate the relationship between NO and COX-2 have revealed both inhibitory and stimulatory effects of NO on COX-2 expression. Genistein, one of soy-isoflavones, is a polyphenolic flavonoid and a potent antioxidant and anti-inflammatory agent. In the present article, the effect of soy-isoflavones on NO production and COX-2 gene expression was examined. NO production by soy-isoflavones was greatly increased even though eNOS and iNOS expression were not different from nontreated control. The increment of NO was accompanied with the elevated expression of COX-2 and the concentrations of PGE2. The COX-2 stimulatory effect of soy-isoflavones appeared to be modulated by ERK-1 and -2 and p38. In mammalian cancer system, incubation with the NO donor sodium nitroprusside (SNP) resulted in a slight upregulation of COX-2, and cotreatment with genistein decreased COX-2 expression possibly by the activation of AMP-activated protein kinase (AMPK).

Role of dietary soy protein in obesity.:Int J Med Sci. 2007 Feb 26;4(2):72-82. Review.Velasquez MT, Bhathena SJ.Department of Medicine, George Washington University Medical Center, Washington, DC, USA.

Soy protein is an important component of soybeans and provides an abundant source of dietary protein. Among the dietary proteins, soy protein is considered a complete protein in that it contains ample amounts of all the essential amino acids plus several other macronutrients with a nutritional value roughly equivalent to that of animal protein of high biological value. Soy protein is unique among the plant-based proteins because it is associated with isoflavones, a group of compounds with a variety of biological properties that may potentially benefit human health. An increasing body of literature suggests that soy protein and its isoflavones may have a beneficial role in obesity. Several nutritional intervention studies in animals and humans indicate that consumption of soy protein reduces body weight and fat mass in addition to lowering plasma cholesterol and triglycerides. In animal models of obesity, soy protein ingestion limits or reduces body fat accumulation and improves insulin resistance, the hallmark of human obesity. In obese humans, dietary soy protein also reduces body weight and body fat mass in addition to reducing plasma lipids. Several potential mechanisms whereby soy protein may improve insulin resistance and lower body fat and blood lipids are discussed and include a wide spectrum of biochemical and molecular activities that favorably affect fatty acid metabolism and cholesterol homeostasis. The biologic actions of certain constituents of soy protein, particularly conglycinin, soyasaponins, phospholipids, and isoflavones, that relate to obesity are also discussed. In addition, the potential of soy protein in causing food allergy in humans is briefly discussed.

Effects of soybean isoflavone dosage and exercise on the serum markers of bone metabolism in ovariectomized rats.:Asia Pac J Clin Nutr. 2007;16 Suppl 1:193-5.Liu K, Ma G, Lv G, Zou Y, Wang W, Liu L, Yan P, Liu Y, Jiang L, Liu Y, Liu Z.Department of Sports Medicine, Dalian Medical University, Dalian, China. l_k_m@126.com

This study was designed to determine whether combined treatments with soybean isoflavone dosage and moderate exercise would exhibit synergistically effects on bone metabolism following the onset of menopause. Fifty 12 wk-old female Wistar rats were assigned to five groups: 1) Sham operated (Sham), 2) ovariectomized (OVX), 3) OVX received soybean isoflavone (OVX-IF), 4) OVX exercised (OVX-EXE) and 5) OVX treated with both soybean isoflavone and exercise (OVX-IF-EXE). All rats were fed a normal diet ad libitum. Daily soybean isoflavone dosage was 50 mg/kg body weight. The vehicle was given in Sham, OVX and OVX-EXE groups. The drugs were all oral administered using a stomach tube. Exercising rats were trained on an uphill treadmill at 20 m/min for 1h/day, 5 days/week. The experimental duration consisted of the adaptation periods of 2 weeks and treatment periods of 8 weeks. The results showed that the uterus relative weights in OVX-EXE, OVX-IF and OVX-IF-EXE groups were all lower than those in Sham, they were higher than those in the OVX group. Serum alkaline phosphates (AKP) activities of OVX was significantly increased as compared to that of Sham (p<0.01). OVX-IF and OVX-IF-EXE respectively decreased the Serum alkaline phosphates activities, as compared to that of OVX (p<0.01). The tartrate-resistant acid phosphatase (TRAP) value of OVX was significantly increased as compared to that of Sham (p<0.05). OVX-IF decreased the TRAP as compared to that of OVX (p<0.05). These results suggest soybean isoflavone and resistance exercise both can restrain ovx-induced bone loss. But their mechanisms may be different.

Inhibition of lipoxygenase by soy isoflavones: evidence of isoflavones as redox inhibitors.:Arch Biochem Biophys. 2007 May 15;461(2):176-85. Epub 2007 Mar 8.Mahesha HG, Singh SA, Rao AG.Department of Protein Chemistry & Technology, Central Food Technological Research Institute, Mysore 570020, India.

Hydroperoxides, the products of lipoxygenase mediated pathways, play a major role in the manifestation of chronic inflammatory diseases. Soy isoflavones act as antioxidants due to their ability to scavenge free radicals. Isoflavones inhibit the activity of soy lipoxygenase-1 and 5-lipoxygenase, from human polymorph nuclear lymphocyte in a concentration dependent manner. Spectroscopic and enzyme kinetic measurements have helped to understand the nature and mechanism of inhibition. Genistein is the most effective inhibitor of soy lipoxygenase 1 and 5-lipoxygenase with IC(50) values of 107 and 125 microM, respectively. Genistein and daidzein are noncompetitive inhibitors of soy lipoxygenase 1 with inhibition constants, K(i), of 60 and 80 microM, respectively. Electron paramagnetic resonance and spectroscopic studies confirm that isoflavones reduce active state iron to ferrous state and prevent the activation of the resting enzyme. A model for the inhibition of lipoxygenase by isoflavones is suggested.

Microwave assisted extraction of soy isoflavones.:Anal Chim Acta. 2007 Apr 11;588(2):274-82. Epub 2007 Feb 12.Rostagno MA, Palma M, Barroso CG.Grupo de Investigaci¨®n Qu¨ªmico Anal¨ªtico del Vino y Productos Agroaliment¨¢rios, Departamento de Qu¨ªmica Anal¨ªtica, Facultad de Ciencias, Universidad de C¨¢diz, P.O. Box 40, 11510 Puerto Real, C¨¢diz, Spain.

A fast and reliable analytical method using microwave assisted extraction has been developed. Several extraction solvents (methanol (MeOH) and ethanol (EtOH), 30-70% in water and water), temperatures (50-150 degrees C), extraction solvent volume, as well as the sample size (1.0-0.1g) and extraction time (5-30 min) were studied for the optimization of the extraction protocol. The optimized extraction conditions for quantitative recoveries were: 0.5 g of sample, 50 degrees C, 20 min and 50% ethanol as extracting solvent. No degradation of the isoflavones was observed using the developed extraction protocol and a high reproducibility was achieved (>95%).

Fast analysis of soy isoflavones by high-performance liquid chromatography with monolithic columns.:Anal Chim Acta. 2007 Jan 23;582(2):243-9. Epub 2006 Sep 16. Rostagno MA, Palma M, Barroso CG.Departamento de Qu¨ªmica Analitica, Facultad de Ciencias, Universidad de C¨¢diz, Puerto Real, C¨¢diz, Spain.

A fast method using high-performance liquid chromatography based on two monolithic columns has been developed for the simultaneous determination of isoflavones extracted from soybeans and derived foods. The 12 main isoflavones were resolved in 10 min in two coupled monolithic columns working at 35 degrees C using a elution gradient of acidified water (0.1% acetic acid) and methanol (0.1% acetic acid) at a flow rate of 5 mL min(-1). Retention time and relative area standard deviations were below 1% for all isoflavones. The method developed was successfully applied to several soy food samples and spiked samples. Total isoflavone concentration in sampled soy foods ranged from 34.28 mg L(-1) to 4.29 mg g(-1).

Soy isoflavones exert differential effects on androgen responsive genes in LNCaP human prostate cancer cells.:J Nutr. 2007 Apr;137(4):964-72.Rice L, Handayani R, Cui Y, Medrano T, Samedi V, Baker H, Szabo NJ, Rosser CJ, Goodison S, Shiverick KT.Department of Radiation Oncology, College of Medicine, University of Florida, Gainesville, FL 32610, USA. lrice@ufl.edu

The high consumption of soy isoflavones in Asian diets has been correlated to a lower incidence of clinically important cases of prostate cancer. This study characterized the effects of a soy-derived isoflavone concentrate (ISF) on growth and gene expression profiles in the LNCaP, an androgen-sensitive human prostate cancer cell line. ISF caused a dose-dependent decrease in viability (P < 0.05) and DNA synthesis (P < 0.01), as well as an accumulation of cells in G(2)/M, and G(0)/G(1) phases of the cell cycle compared with controls. Using Affymetrix oligonucleotide DNA microarrays (U133A), we determined that ISF upregulated 80 genes and downregulated 33 genes (P < 0.05) involving androgen-regulated genes and pathways controlling cell cycle, metabolism, and intracellular trafficking. Changes in the expression of the genes of interest, identified by microarrays, were validated by Western immunoblot, Northern blot, and luciferase reporter assays. Prostate-specific antigen, homeobox protein NKX3, and cyclin B mRNA were significantly reduced, whereas mRNA was significantly upregulated for p21(CIP1), a major cell cycle inhibitory protein, and fatty acid and cholesterol synthesis pathway genes. ISF also significantly increased cyclin-dependent kinase inhibitor p27(KIP1) and FOXO3A/FKHRL1, a forkhead transcription factor. A differential pattern of androgen-regulated genes was apparent with genes involved in prostate cancer progression being downregulated by ISF, whereas metabolism genes were upregulated. In summary, we found that ISF inhibits the growth of LNCaP cells through the modulation of cell cycle progression and the differential expression of androgen-regulated genes. Thus, ISF treatment serves to identify new therapeutic targets designed to prevent proliferation of malignant prostate cells.

Soy protein and isoflavones influence adiposity and development of metabolic syndrome in the obese male ZDF rat.:Ann Nutr Metab. 2007;51(1):42-52. Epub 2007 Mar 14.Davis J, Higginbotham A, O'Connor T, Moustaid-Moussa N, Tebbe A, Kim YC, Cho KW, Shay N, Adler S, Peterson R, Banz W.Southern Illinois University, Carbondale, IL 62901-4317, USA.

BACKGROUND/AIMS: Previously, we demonstrated that soy protein ameliorates the diabetic phenotype in several rodent models of obesity and metabolic syndrome (MS). This study was designed to further elucidate factors related to adiposity, glycemic control, and renal function in male Zucker Diabetic Fatty (ZDF/Lepr(fa)) rats. METHODS: Animals were randomly assigned to one of four diets: control, casein (C); low isoflavone (LIS) soy protein; high isoflavone (HIS) soy protein, or casein + rosiglitazone (CR) for 11 weeks. At sacrifice, physiological, biochemical, and molecular parameters were determined. RESULTS: Body weight and total adiposity were higher in LIS and CR diet groups despite lower food intake. Additionally, these animals exhibited differential regulation of adipose-specific proteins (PPAR-gamma and GLUT4) and enzyme activity (FAS and GPDH). HIS-fed animals had reduced total and liver adiposity. Glycemic control was prolonged in both soy-based and rosiglitazone (RGZ) groups. Renal dysfunction was significantly reduced in soy-fed and RGZ-treated rodents as demonstrated by lower levels of proteinuria and dilated tubules with proteinaceous casts. CONCLUSION: Collectively, these data provide evidence that soy protein with low or high isoflavone content may have therapeutic significance in reducing severity of diabetes, MS, and renal disease as demonstrated in this preclinical model.

Validation of a phytoestrogen food frequency questionnaire with urinary concentrations of isoflavones and lignan metabolites in premenopausal women.:J Am Coll Nutr. 2007 Feb;26(1):76-82.French MR, Thompson LU, Hawker GA.Osteoporosis Research Program, Women's College Hospital, 76 Grenville Street, Toronto, Ontario M5S 1B2, CANADA.

OBJECTIVE: The purpose of this study was to examine the association between dietary intake of phytoestrogens estimated by a food frequency questionnaire (FFQ) with urinary metabolites. METHODS: Participants were 26 premenopausal, Caucasian women aged 25 to 42 years. Dietary intake of isoflavones (genistein and daidzein) and lignans (secoisolariciresinol and matairesinol) were estimated by a 53-item interviewer-administered FFQ on two occasions, reflecting 'habitual' (previous 2 months) and 'recent' (previous 2 days) dietary intake. Isoflavone (genistein, daidzein) and lignan (enterolactone, enterodiol and secoisolariciresinol) concentrations were measured in 24-hour urine samples by gas chromatography-mass spectrometry. Correlations between FFQ (habitual and recent, separately) and urinary metabolite values were assessed using Spearman correlation coefficients. RESULTS: Mean habitual isoflavone and lignan intakes were 13.7 mg/day and 13.8 mg/day, respectively. Mean urinary concentrations of isoflavones and lignans were 17.4 micromol/day and 20.6 micromol/day, respectively. Recent and habitual isoflavone intakes were correlated with urinary excretion of metabolites (r = 0.64, p < 0.001 and r = 0.54, p = 0.004, respectively). Urinary excretion of lignans was also modestly correlated with recent and habitual lignan intakes (r = 0.46, p = 0.02 and r = 0.40, p = 0.05, respectively). CONCLUSIONS: Our results support the use of this FFQ as a measure of dietary isoflavone and lignan intake in epidemiological studies.

Modulation of soy isoflavones bioavailability and subsequent effects on bone health in ovariectomized rats: the case for equol.:Osteoporos Int. 2007 May;18(5):671-9. Epub 2007 Feb 28.Mathey J, Mardon J, Fokialakis N, Puel C, Kati-Coulibaly S, Mitakou S, Bennetau-Pelissero C, Lamothe V, Davicco MJ, Lebecque P, Horcajada MN, Coxam V.Groupe Ost¨¦oporose, U3M, INRA Theix, Saint Gen¨¨s-Champanelle, France.

INTRODUCTION: Soy products are of particular interest because of their potential health benefits in a range of hormonal conditions, such as osteoporosis, due to their high content in phytoestrogens. Because equol, the main metabolite from soy isoflavones, is thought to be powerful, the present study was designated to evaluate the bone-sparing effects of equol by either providing the molecule through the diet or by eliciting its endogenous production by modulating intestinal microflora by short-chain fructooligosaccharides (sc-FOS) or live microbial (Lactobacillus casei) together with daidzein, its precursor. METHODS: A comparison with daidzein and genistein was also performed. Rats (3 months old) were ovariectomised (OVX) or sham-operated (SH). Ovariectomised rats were randomly assigned to six experimental diets for 3 months: a control diet (OVX), the control diet supplemented with either genistein (G), or daidzein (D), or equol (E) at the level of 10 microg/g body weight/d. The remaining OVX rats were given daidzein at the dose of 10 mug/g body weight/d, simultaneously with short-chain FOS (Actilight, Beghin-Meiji) (D+FOS) or Lactobacillus casei (Actimel, Danone) (D+L). The SH rats were given the same control diet as OVX. RESULTS: Genistein, daidzein or equol exhibited a bone sparing effect. Indeed, total femoral bone mineral density (BMD) was significantly enhanced (compared to that of OVX rats), as was the metaphyseal compartment. Bone strength was improved by E consumption, but not by genistein or daidzein given alone. As far as the FOS diet is concerned, the addition of prebiotics significantly raised efficiency of the daidzein protective effect on both femoral BMD and mechanical properties. The effects of lactobacillus were similar, except that the increase in metaphyseal-BMD was not significant. CONCLUSION: In conclusion, long-term equol consumption, like genistein and daidzein, in the ovariectomized rat, provides bone sparing effects. Adding indigestible sugars, such as FOS or live microbial as L. casei, in the diet significantly improves daidzein protective effects on the skeleton.

Down-regulation of apurinic/apyrimidinic endonuclease 1/redox factor-1 expression by soy isoflavones enhances prostate cancer radiotherapy in vitro and in vivo.:Cancer Res. 2007 Mar 1;67(5):2141-9. Raffoul JJ, Banerjee S, Singh-Gupta V, Knoll ZE, Fite A, Zhang H, Abrams J, Sarkar FH, Hillman GG.Department of Radiation Oncology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201, USA.

We previously showed that genistein, the major bioactive component of soy isoflavones, acts as a radiosensitizer and potentiates prostate tumor cell killing by radiation in vitro and in animal tumor models in vivo. However, when given alone in vivo, pure genistein promoted increased lymph node metastasis, which was not observed with a soy isoflavone mixture consisting of genistein, daidzein, and glycitein. In this study, we show that soy inhibit tumor cell growth and potentiates radiation-induced cell killing in vitro like pure genistein. In an orthotopic model, combining soy isoflavones with tumor irradiation inhibited prostate tumor growth. To determine the molecular mechanisms by which soy isoflavones potentiate radiotherapy, we investigated apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) and nuclear factor kappaB (NF-kappaB), two signaling molecules involved in survival pathways. Soy isoflavones decreased APE1/Ref-1 expression in vitro, whereas radiation up-regulated it. Pretreatment with soy isoflavones followed by radiation inhibited APE1/Ref-1 expression. APE1/Ref-1 decrease correlated with decreased DNA-binding activity of NF-kappaB mediated by soy isoflavones and radiation, thus promoting cell killing. In vivo treatment of prostate tumors with soy isoflavones and radiation down-regulated APE1/Ref-1 protein expression and NF-kappaB activity, confirming the molecular alterations observed in vitro. The down-regulation of APE1/Ref-1 and NF-kappaB by isoflavones, in vitro and in vivo, supports our hypothesis that these markers represent biological targets of isoflavones. Indeed, a 2-fold increase in APE1/Ref-1 expression, obtained by cDNA transfection, resulted in a 2-fold increase in NF-kappaB DNA-binding activity, and both of which were down-regulated by soy isoflavones, confirming the cross-talk between these molecules and, in turn, causing radiosensitization.

Soy isoflavones enhance radiotherapy in a metastatic prostate cancer model.:Int J Cancer. 2007 Jun 1;120(11):2491-8.Raffoul JJ, Banerjee S, Che M, Knoll ZE, Doerge DR, Abrams J, Kucuk O, Sarkar FH, Hillman GG.Department of Radiation Oncology, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI 48201, USA.

We previously reported that genistein, the bioactive isoflavone of soybeans, acts as a radiosensitizer for prostate cancer. Pretreatment of tumor cells with genistein potentiated radiation-induced killing in vitro and in orthotopic models in vivo. However, pure genistein promoted increased lymph node metastasis, when administered alone in vivo. We investigated in vitro and in vivo the effects of soy isoflavones (genistein, daidzein and glycitein) as soy pills of similar composition are used in human interventions but not pure genistein. Soy isoflavones inhibited cell survival and potentiated radiation cell killing in PC-3 tumor cells, in vitro. Increased cell killing correlated with inhibition of antiapoptotic molecules Bcl-xL and survivin, upregulation of proapoptotic Bax molecule and PARP cleavage, suggesting activation of apoptotic pathways. In vivo, using the PC-3 orthotopic metastatic mouse model, soy isoflavones and prostate tumor irradiation led to enhanced control of primary tumor growth and metastasis, as observed with pure genistein and radiation. Interestingly, treatment with soy isoflavones did not increase metastasis to para-aortic lymph nodes in contrast to the consistent increase caused by pure genistein. Histologically prostate tumors, treated with soy isoflavones and radiation, showed tumor destruction and in situ tissue alterations, comparable with genistein and radiation effects. However, genistein, but not soy isoflavones, caused induction of HIF1-alpha in prostate tumors, suggesting that induction of hypoxia by pure genistein could contribute to increased metastasis. Our studies demonstrate the safety and potential role of soy isoflavones for enhancing the therapeutic effect of radiotherapy in prostate cancer.

Isoflavone treatment for acute menopausal symptoms.:Menopause. 2007 May-Jun;14(3 Pt 1):468-73.Cheng G, Wilczek B, Warner M, Gustafsson JA, Landgren BM.Department of Biosciences and Nutrition, Karolinska Institutet, Novum, Huddinge, Sweden. guojun.cheng@mednut.ki.se

OBJECTIVE: The onset of climacteric symptoms (hot flashes and night sweats) is the primary reason for perimenopausal women to start hormone therapy. The association of a lower incidence of postmenopausal symptoms with high intake of soybeans in Asian women suggests that phytoestrogens are an alternative to estrogen therapy. The main effective compounds in soybean are isoflavones, which have a higher binding affinity to estrogen receptor beta than to estrogen receptor alpha. The aim of present study was to evaluate the effects of isoflavone treatment in postmenopausal women. DESIGN: This was a double-blind prospective study. Sixty healthy postmenopausal women were randomly assigned by computer into two groups to receive 60 mg isoflavones or placebo daily for 3 months. Before and after treatment, climacteric symptoms were recorded; serum was collected to measure the levels of lipoprotein lipids, estradiol, and follicle-stimulating hormone; and biopsy specimens from endometrium and breast were analyzed to investigate the expression level of steroid receptors and proliferation. Endometrial thickness was measured by ultrasound. RESULTS: Fifty-one women finished the 12-week study. In women receiving 60 mg isoflavones daily, hot flashes and night sweats were reduced by 57% and 43%, respectively. The treatment did not change the levels of circulating estradiol or follicle-stimulating hormone. Immunohistochemical staining of endometrial and breast biopsy specimens revealed that isoflavones did not affect expression levels of steroid receptors; estrogen receptors alpha, beta, and betacx; progesterone receptors A and B; or the proliferation marker Ki67. No side effects on body weight or lipoprotein lipids were observed. CONCLUSIONS: This short-term prospective study implies that isoflavones could be used to relieve acute menopausal symptoms.

Memory performance of hypercholesterolemic mice in response to treatment with soy isoflavones.:Neurosci Res. 2007 Apr;57(4):544-9. Epub 2007 Jan 8. Liu YQ, Xin TR, L¨¹ XY, Ji Q, Jin Y, Yang HD.College of Life Sciences, Nankai University, Tianjin 300071, PR China. liuyanq@nankai.edu.cn

The aim of this study is to investigate the memory performance of hypercholesterolemic mice in response to soy isoflavones (SI) treatment and the mechanism involved. In this study, 64 mice were randomly divided into four groups: control, high lipid diet without SI, high lipid diet with a low SI level (50 mg/kg bw) and high lipid diet with a high SI level (100 mg/kg bw). The experimental period was 30 days. The results indicated that the mice given the different treatments showed the different percentages of good, medium and poor memory performance. chi(2) analysis revealed significant difference in memory performance (P<0.05) between the high lipid diet without SI group and the high lipid diet with a low SI level group or high lipid diet with a high SI level group. Moreover, SI treatment resulted in a decrease in blood cholesterol (TC) level (high lipid diet without SI group versus high lipid diet with a low SI level group or high lipid diet with a high SI level group, P<0.05) and triglyceride (TG) level (high lipid diet without SI group versus high lipid diet with a low SI level group or high lipid diet with a high SI level group, P<0.05). In addition, SI treatment resulted in a significant decrease in acetylcholinesterase (AChE) activity and significant increases in glutamic acid and aspartic acid contents in the frontal cerebral cortex and hippocampus. The results suggest that SI improve the memory performance of hypercholesterolemic mice, and the mechanism underlying the improvement might closely correlate with its roles in decreasing high blood lipid levels and modulating the metabolism of neurotransmitters such as acetylcholine and amino acids in brain areas of hypercholesterolemic mice.

AVPV neurons containing estrogen receptor-beta in adult male rats are influenced by soy isoflavones.:BMC Neurosci. 2007 Feb 1;8:13.Bu L, Lephart ED.Physiology and Developmental Biology Department and Neuroscience Center Brigham Young University, Provo, UT, USA. neuroscience@byu.edu

BACKGROUND: Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. It is known that 17beta-estradiol induces apoptosis in anteroventral periventricular nucleus (AVPV) in rat brain. Also, there is evidence that consumption of soy isoflavones reduces the volume of AVPV in male rats. Therefore, in this study, we examined the influence of dietary soy isoflavones on apoptosis in AVPV of 150 day-old male rats fed either a soy isoflavone-free diet (Phyto-free) or a soy isoflavone-rich diet (Phyto-600). RESULTS: The occurrence of apoptosis in AVPV was examined by TUNEL staining. The incidence of apoptosis was about 10 times higher in the Phyto-600 group (33.1 +/- 1.7%) than in the Phyto-free group (3.6 +/- 1.0%). Furthermore, these apoptotic cells were identified as neurons by dual immunofluorescent staining of GFAP and NeuN as markers of astrocytes and neurons, respectively. Then the dopaminergic neurons in AVPV were detected by immunohistochemistry staining of tyrosine hydroxylase (TH). No significant difference in the number of TH neurons was observed between the diet treatment groups. When estrogen receptor (ER) alpha and beta were examined by immunohistochemistry, we observed a 22% reduction of ERbeta-positive cell numbers in AVPV with consumption of soy isoflavones, whereas no significant change in ERalpha-positive cell numbers was detected. Furthermore, almost all the apoptotic cells were ERbeta-immunoreactive (ir), but not ERalpha-ir. Last, subcutaneous injections of equol (a major isoflavone metabolite) that accounts for approximately 70-90% of the total circulating plasma isoflavone levels did not alter the volume of AVPV in adult male rats. CONCLUSION: In summary, these findings provide direct evidence that consumption of soy isoflavones, but not the exposure to equol, influences the loss of ERbeta-containing neurons in male AVPV.

How isoflavone levels in common rodent diets can interfere with the value of animal models and with experimental results.:Lab Anim. 2007 Jan;41(1):1-18. Review.Jensen MN, Ritskes-Hoitinga M.Central Animal Facility, University Medical Center, St Radboud, PO Box 9101, NL-6500 HB Nijmegen, The Netherlands.

Phytoestrogens are a diverse group of plant-derived compounds structurally or functionally mimicking mammalian oestrogens. A variety of effects, in vitro, in animal models and in humans, have been attributed to these compounds. It is generally not appreciated that many commercial rodent diets are formulated with soy as a source of protein and thus large daily doses of phytoestrogens in the form of isoflavones are delivered to the animals. The content of isoflavones in laboratory diets depends on a number of factors and, therefore, varies considerably, both between different formulations, and also from batch to batch of the same formulation. Dietary isoflavones can influence a number of different endpoints, rendering the dietary levels of such compounds an important experimental factor to consider. The levels of isoflavones in common laboratory diets are reviewed in relation to the dietary levels influencing different endpoints.

Effect of isolated isoflavone supplementation on ABCA1-dependent cholesterol efflux potential in postmenopausal women.:Menopause. 2007 Mar-Apr;14(2):293-9.Badeau R, Jauhiainen M, Metso J, Nikander E, Tikkanen MJ, Ylikorkala O, Mikkola TS.Department of Obstetrics and Gynecology, Helsinki University Central Hospital, Finland.

OBJECTIVE: Isoflavones may display beneficial health effects in postmenopausal women. We studied in a clinical trial whether isolated isoflavone treatment in postmenopausal women could affect reverse cholesterol transport as evaluated by adenosine triphosphate-binding cassette A1- (ABCA1), dependent cholesterol efflux from macrophages. In addition, various serum lipid and lipoprotein parameters were investigated. Furthermore, we separately assessed equol-producing and non-equol-producing women. DESIGN: Postmenopausal women (n=56) were treated with either isoflavone or placebo tablets for 3 months in a crossover design, separated by a 2-month washout period. Fifteen women were classified as equol producers, and 15 women were classified as non-equol producers. Serum samples were collected before and after each treatment period. [H]-Cholesterol-labeled J774 macrophage cells, with and without ABCA1 up-regulation, were incubated with the samples, and ABCA1-dependent cholesterol efflux and serum lipid and lipoprotein levels were assessed. RESULTS: Serum promoted 3.1%+/-1.1% and 3.2%+/-1.1% cholesterol efflux from macrophages after isoflavone and placebo treatment, respectively. Thus, isoflavone supplementation did not affect ABCA1-dependent cholesterol efflux to serum. However, as a novel finding, isoflavone treatment increased a subclass of high-density lipoprotein, the pre-beta high-density lipoprotein levels by 18% without affecting any other serum lipid concentrations. ABCA1-facilitated cholesterol efflux and lipid parameters did not differ between equol-producing and non-equol-producing women. CONCLUSION: In postmenopausal women, isolated isoflavone treatment does not affect ABCA1-dependent cholesterol efflux potential from macrophages but increases circulating pre-beta high-density lipoprotein level, which could provide beneficial vascular effects.

Effects of soy protein isolate and moderate exercise on bone turnover and bone mineral density in postmenopausal women.:Menopause. 2007 May-Jun;14(3 Pt 1):481-8.Evans EM, Racette SB, Van Pelt RE, Peterson LR, Villareal DT.Division of Geriatrics and Nutritional Sciences, Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA. elevans@uiuc.edu

OBJECTIVE: The aim of this study was to assess the independent and additive effects of soy protein isolate (SPI) and moderate-intensity exercise (EX) on bone turnover and bone mineral density (BMD). DESIGN: This study used a placebo-controlled, double-blind (soy), randomized 2 (SPI vs milk protein isolate [MPI]) x 2 (EX vs no EX) design. Sixty-one postmenopausal women were randomized, and 43 (62 +/- 5 y) completed the 9-month intervention (SPI, n = 10; MPI, n = 12; SPI + EX, n = 11; MPI + EX, n = 10). Serum C-terminal cross-linked telopeptides of type I collagen and serum bone-specific alkaline phosphatase were measured as markers of bone resorption and formation, respectively. BMD was measured by dual-energy x-ray absorptiometry. RESULTS: At 9 months, SPI reduced serum C-terminal cross-linked telopeptides (-13.3% +/- 15.3% vs -1.5% +/- 21.0%; P = 0.02) and serum bone-specific alkaline phosphatase (-4.7% +/- 14.7% vs 6.5% +/- 17.7%; P = 0.02) compared to milk protein isolate. EX attenuated the reduction in serum C-terminal cross-linked telopeptides (-1.9% +/- 21.6% vs -12.4% +/- 15.3%; P = 0.04); however, no EX effects were apparent in serum bone-specific alkaline phosphatase at 9 months (2.8% +/- 16.1% vs -1.0% +/- 18.3%; P = 0.28). Neither SPI nor EX affected BMD at any site; however, change in BMD was related to change in fat mass (r = 0.40, P < 0.05). CONCLUSIONS: In postmenopausal women (1) SPI reduces bone turnover with no impact on BMD over 9 months; (2) moderate-intensity endurance exercise training did not favorably alter bone turnover and had no impact on BMD; and (3) there were no additive effects of soy and exercise on bone turnover or BMD.

Dietary soy protein isolate modifies hepatic retinoic acid receptor-beta proteins and inhibits their DNA binding activity in rats.:J Nutr. 2007 Jan;137(1):1-6.Xiao CW, Mei J, Huang W, Wood C, L'abb¨¦ MR, Gilani GS, Cooke GM, Curran IH.Nutrition Research Division, Food Directorate, Health Products and Food Branch, Health Canada, 2203C Banting Research Centre, Ottawa, ON, Canada K1A 0L2. chaowu_xiao@hc-sc.gc.ca

Retinoic acid receptors (RAR) belong to the same nuclear receptor superfamily as thyroid hormone receptors (TR) that were previously shown to be modulated by dietary soy protein isolate (SPI). This study has examined the effect of dietary SPI and isoflavones (ISF) on hepatic RAR gene expression and DNA binding activity. In Expt. 1, Sprague-Dawley rats were fed diets containing 20% casein or 20% alcohol-washed SPI in the absence or presence of increasing amounts of ISF (5-1250 mg/kg diet) for 70, 190, or 310 d. In Expt. 2, weanling Sprague-Dawley rats were fed diets containing 20% casein with or without supplemental ISF (50 mg/kg diet) or increasing amounts of alcohol-washed SPI (5, 10, and 20%) for 90 d. Intake of soy proteins significantly elevated hepatic RARbeta2 protein content dose-dependently compared with a casein diet, whereas supplemental ISF had no consistent effect. Neither RARbeta protein in the other tissues measured nor the other RAR (RARalpha and RARgamma) in the liver were affected by dietary SPI, indicating a tissue and isoform-specific effect of SPI. RARbeta2 mRNA abundances were not different between dietary groups except that its expression was markedly suppressed in male rats fed SPI for 310 d. DNA binding activity of nuclear RARbeta was significantly attenuated and the isoelectric points of RARbeta2 were shifted by dietary SPI. Overall, these results show for the first time, to our knowledge, that dietary soy proteins affect hepatic RARbeta2 protein content and RARbeta DNA binding activity, which may contribute to the suppression of retinoid-induced hypertriglyceridemia by SPI as reported.

Genistein and resveratrol: mammary cancer chemoprevention and mechanisms of action in the rat.:Expert Rev Anticancer Ther. 2006 Dec;6(12):1699-706. Review.Whitsett TG, Lamartiniere CA.University of Alabama at Birmingham, Department of Pharmacology and Toxicology, Birmingham, AL, USA. twhitset@uab.edu

The environment, including diet, plays a critical role in a woman's subsequent risk of breast cancer. Two dietary polyphenols that have received attention from the health and research communities for their ability to protect against breast cancer are: genistein, a component of soy; and resveratrol, a phytoalexin found in red grapes and red wine. We and others have shown that both genistein and resveratrol can protect against mammary cancer in rodents. The timing of exposure to genistein appears critical for its mammary protective effects. It has been reported that genistein early in life causes enhanced mammary gland differentiation, alterations in cell proliferation and apoptosis, and upregulation of tumor-suppressor genes. With resveratrol in the diet, changes in cell proliferation and apoptosis in terminal ductal structures of the mammary gland might help to explain its protective effects. We conclude that genistein and resveratrol can protect against breast cancer by regulating important mammary growth and differentiation pathways.

Effect of soy protein-containing isoflavones on lipoproteins in postmenopausal women.:Menopause. 2007 Jan-Feb;14(1):106-14.Allen JK, Becker DM, Kwiterovich PO, Lindenstruth KA, Curtis C.Johns Hopkins University School of Nursing, Baltimore, MD 21205, USA. jallen@son.jhmi.edu

OBJECTIVE: Some clinical trials have demonstrated a beneficial effect of dietary soy protein on improving lipoproteins. Research also has documented that serum lipoproteins and some lipoprotein subclasses are altered as a consequence of menopause, resulting in a more atherogenic lipid profile. The purpose of this study was to determine the effects of isolated soy protein-containing isoflavones on lipoproteins and lipoprotein subclasses in both African American and white postmenopausal women with borderline to moderate low-density lipoprotein cholesterol elevations. DESIGN: This was a randomized, double-blind, controlled clinical trial including 216 postmenopausal women. After a 4-week run-in period with a casein protein-based supplement, participants were randomly assigned to continue the casein placebo or receive soy protein-containing isoflavones for a period of 12 weeks. RESULTS: In the soy group, the total cholesterol, low-density lipoprotein cholesterol, and low-density lipoprotein particle number decreased significantly as compared with the placebo group at 6 weeks. Although this decrease continued at 12 weeks in the soy group, the difference from the placebo group was attenuated for total cholesterol and low-density lipoprotein particle number. Multivariate analyses controlling for age, race, change in weight, change in dietary fat intake, and change in kilocalorie energy expenditure revealed that treatment remained a significant independent predictor of change in total cholesterol (P = 0.01), low-density lipoprotein cholesterol (P = 0.02), and low-density lipoprotein particle number (P = 0.002) after 6 weeks of dietary soy. CONCLUSIONS: Increased consumption of soy protein replacing animal protein that is high in fat may help improve atherogenic lipid profiles.

Effect of soy isoflavone protein and soy lecithin on endothelial function in healthy postmenopausal women.:Menopause. 2007 Jan-Feb;14(1):141-9. Evans M, Njike VY, Hoxley M, Pearson M, Katz DL.Yale Prevention Research Center, Derby, CT 06418, USA.

OBJECTIVE: To assess the effects of soy isoflavone protein concentrate and soy lecithin on endothelial function, measured as flow-mediated dilation (FMD) of the brachial artery in healthy postmenopausal women. DESIGN: This was a randomized, double-blind, placebo-controlled crossover trial with 25 participants (mean age, 61 years; body mass index, 25.46 kg/m2). The women underwent endothelial function testing at baseline and after 4 weeks of randomly assigned treatment with intervening 4-week washout periods. Treatment assignments included soy isoflavone protein (25 g/day) and soy lecithin (20 g/day), soy isoflavone protein (25 g/day) and placebo lecithin, placebo protein and soy lecithin (20 g/day), and double placebo. FMD and serum lipid levels were assessed at baseline and the end of each 4-week treatment phase. RESULTS: Twenty-two women completed the trial. No statistically significant (P > 0.05) difference was seen in FMD between treatment groups. A trend was suggested with FMD highest after treatment with soy protein plus lecithin (7.50 +/- 9.85), followed by soy protein (5.51 +/- 10.11), soy lecithin (5.35 +/- 6.13), and lowest after placebo (4.53 +/- 7.84). Soy isoflavone protein and soy lecithin significantly increased the high-density lipoprotein/low-density lipoprotein ratio (soy isoflavone protein plus soy lecithin, 0.64 +/- 0.19, P < 0.0001; soy isoflavone protein plus placebo lecithin, 0.58 +/- 0.17, P = 0.0058; placebo protein plus soy lecithin, 0.65 +/- 0.18, P < 0.0001) relative to the baseline value (0.49 +/- 0.15). CONCLUSIONS: In this sample of healthy postmenopausal women, soy isoflavone protein and soy lecithin significantly improved the lipid profile. A favorable influence on endothelial function could not be confirmed.

Nod factor enhances calcium uptake by soybean.:Plant Physiol Biochem. 2006 Nov-Dec;44(11-12):866-72. Epub 2006 Oct 16.Supanjani S, Habib A, Mabood F, Lee KD, Donnelly D, Smith DL.Department of Plant Science, McGill University, Macdonald Campus, Sainte Anne de Bellevue, Que, Canada.[PMID: 17092733]

Inoculation with rhizobia or application of Nod factors (lipo-chitooligosaccharides, LCOs) causes transient increases in cytosolic calcium concentration in root hairs of legume plants. We conducted experiments to evaluate whether application of LCO and inoculation with rhizobia improved (45)CaCl(2) uptake into soybean (Glycine max [L.] Merr.) leaves. Roots of soybean seedlings with one developing trifoliolate were immersed in Murashige and Skoog (MS) basal liquid medium containing treatment solutions and (45)CaCl(2), and the plants were incubated under continuous light. After 24 h, leaf samples were taken, and their radioactivity levels were determined. Addition of NodBj-V (C18:1 MeFuc) at a concentration of 10(-7) M increased (45)Ca(2+) uptake. Inoculation with genistein-induced Bradyrhizobium japonicum strain 532C and USDA3 also increased (45)Ca(2+) uptake; whereas, inoculation with strain Bj-168, a nodC-mutant incapable of producing LCO, did not. Rhizobia that do not normally nodulate soybean, i.e. Rhizobium leguminosarum, and Sinorhizobium meliloti did not affect calcium uptake, nor did the tetramer or pentamer of chitosan, or lumichrome. Surprisingly, Rhizobium sp. NGR234, which can nodulate some types of soybean, although without effective N(2)-fixation, also did not affect calcium uptake. This work suggests that the rhizobial symbiosis, in addition to its known role in provision of nitrogen fixation, also improves early calcium uptake into soybean plants.

Regulatory mechanism of food factors in bone metabolism and prevention of osteoporosis.:[PMID: 17077614]

Aging induces a decrease in bone mass, and osteoporosis with its accompanying decrease in bone mass is widely recognized as a major public health problem. Bone loss with increasing age may be due to decreased bone formation and increased bone resorption. Pharmacologic and nutritional factors may prevent bone loss with aging, although chemical compounds in food and plants which act on bone metabolism are poorly understood. We have found that isoflavones (including genistein and daidzein), which are contained in soybeans, have a stimulatory effect on osteoblastic bone formation and an inhibitory effect on osteoclastic bone resorption, thereby increasing bone mass. Menaquinone-7, an analogue of vitamin K(2) which is abundant in fermented soybeans, has been demonstrated to stimulate osteoblastic bone formation and to inhibit osteoclastic bone resorption. Of various carotenoids, beta-cryptoxanthin, which is abundant in Satsuma mandarin (Citrus unchiu MARC), has a stimulatory effect on osteoblastic bone formation and an inhibitory effect on osteoclastic bone resorption. The supplementation of these factors has a preventive effect on bone loss induced by ovariectomy in rats, which are an animal model of osteoporosis, and their intake has been shown to have a stimulatory effect on bone mass in humans. Factors with an anabolic effect on bone metabolism were found in extracts obtained from wasabi leafstalk (Wasabi japonica MATSUM), the marine alga Sargassum horneri, and bee pollen Cistus ladaniferus. Phytocomponent p-hydroxycinnamic acid was also found to have an anabolic effect on bone metabolism. Food chemical factors thus play a role in bone health and may be important in the prevention of bone loss with increasing age.

Endogenous isoflavones are essential for the establishment of symbiosis between soybean and Bradyrhizobium japonicum.:Plant J. 2006 Oct;48(2):261-73.[PMID: 17018035]Subramanian S, Stacey G, Yu O.Donald Danforth Plant Science Center, St Louis, MO 63132, USA.

Legume iso/flavonoids have been implicated in the nodulation process, but questions remain as to their specific role(s), and no unequivocal evidence exists showing that these compounds are essential for nodulation. Two hypotheses suggest that the primary role of iso/flavonoids is their ability to induce rhizobial nod gene expression and/or their ability to modulate internal root auxin concentrations. The present work provides direct, genetic evidence that isoflavones are essential for nodulation of soybean roots because of their ability to induce the nodulation genes of Bradyrhizobium japonicum. Expression of isoflavone synthase (IFS), a key enzyme in the biosynthesis of isoflavones, is specifically induced by B. japonicum. When IFS was silenced using RNA interference in soybean hairy root composite plants, these plants had severely reduced nodulation. Surprisingly, pre-treatment of B. japonicum or exogenous application to the root system of either of the major soybean isoflavones, daidzein or genistein, failed to restore normal nodulation. Silencing of chalcone reductase led to very low levels of daidzein and increased levels of genistein, but did not affect nodulation, suggesting that the endogenous production of genistein was sufficient to support nodulation. Consistent with a role for isoflavones as endogenous regulators of auxin transport in soybean roots, silencing of IFS resulted in altered auxin-inducible gene expression and auxin transport. However, use of a genistein-hypersensitive B. japonicum strain or purified B. japonicum Nod signals rescued normal nodulation in IFS-silenced roots, indicating that the ability of isoflavones to modulate auxin transport is not essential to nodulation.

Evaluation of ex vivo human skin permeation of genistein and daidzein.:Drug Deliv. 2006 Nov-Dec;13(6):411-5.Minghetti P, Cilurzo F, Casiraghi A, Montanari L.Istituto di Chimica Farmaceutica e Tossicologica, Universita degli Studi di Milano, Milano, Italy. paola.minghetti@unimi.it.[PMID: 17002968]

The percutaneous absorption of genistein (GEN) and daidzein (DAI), whose oestrogenic-like activity is well known, is scantily investigated. In this work the ability of GEN and DAI to reach therapeutic steady-state plasma concentrations following transdermal administration was studied. The skin permeation studies were conducted by using modified Franz diffusion cell and human epidermis as a membrane. PEG400 was the most effective vehicle for both molecules. On the basis of the ex vivo permeation results and estimating therapeutic plasma concentration, we assume that pure GEN can be efficaciously administered by the transdermal route.

Functional components in soybean cake and their effects on antioxidant activity.:J Agric Food Chem. 2006 Oct 4;54(20):7544-55.Kao TH, Chen BH.Department of Nutrition and Food Sciences, Fu Jen University, Taipei, Taiwan.[PMID: 17002420]

The antioxidant activities of four fractions of isoflavones from soybean cake were evaluated and compared with those of ISO-1 and ISO-2 fractions, five isoflavone standards, and mixtures of two or four isoflavone standards, as well as four commercial antioxidants, using DPPH, TEAC, reducing power, metal ion chelating, conjugated diene, and TBARS assays. Both malonylglucoside and glucoside fractions were isolated using preparative chromatography with Diaion HP-20 as adsorbent, whereas acetylglucoside and aglycone fractions were separated with silica gel as adsorbent. The other two fractions, ISO-1 and ISO-2, were soybean cake extracts containing 12 isoflavones for the former and a combination of 4 fractions for the latter. Both acetylglucoside and ISO-1 fractions exhibited the highest efficiency in scavenging DPPH free radicals, whereas all six fractions were effective in inhibiting conjugated diene formation. However, a low reducing power was observed for all six fractions and isoflavone standards. The aglycone fraction and genistein standard showed a pronounced increase of TEAC value and a moderate decrease of TBARs value. For chelating metal ions, both ISO-1 and ISO-2 fractions were the most efficient. Overall, the isoflavone fractions showed a better antioxidant activity than the isoflavone standards, probably caused by the presence of some other functional components such as saponin, flavonoid, and phenolic compounds in soybean cake.

Heat and pH effects on the conjugated forms of genistin and daidzin isoflavones.:J Agric Food Chem. 2006 Oct 4;54(20):7495-502.Mathias K, Ismail B, Corvalan CM, Hayes KD.Food Science Department, Purdue University, 745 Agriculture Mall Drive, West Lafayette, Indiana 47907, USA.[PMID: 17002413]

Isoflavones occur primarily as glycosides (namely, malonyl-, acetyl-, and non-conjugated beta-glycosides) and a small percentage as the bioactive aglycon. The different chemical structures of isoflavones can dictate their stability during processing. Therefore, our objective was to determine the effects of pH and thermal treatments on conjugated isoflavones with regard to interconversions and loss. Conjugated daidzin and genistin were heated at 25, 80, and 100 degrees C under neutral, acidic, and basic conditions. Changes in isoflavone derivatives were monitored using high-performance liquid chromatography. Along with interconversions, considerable loss in total known isoflavone derivatives was noted for each isoflavone, especially under elevated pH and temperature. The malonylglycosides showed more stability than acetylglycosides, especially under acidic conditions. Overall, loss in isoflavone derivatives was significantly higher for daidzin than for genistin glycoside forms. Our results highlighted the significance of chemical structure with regard to stability, which is a key factor in determining soy processing conditions.

Genistein, a soy isoflavone, up-regulates expression of antioxidant genes: involvement of estrogen receptors, ERK1/2, and NFkappaB.:FASEB J. 2006 Oct;20(12):2136-8. Epub 2006 Sep 11.Borras C, Gambini J, Gomez-Cabrera MC, Sastre J, Pallardo FV, Mann GE, Vina J. Catholic University of Valencia, Valencia, Spain.[PMID: 16966488]

We have previously reported that estrogens up-regulate longevity-associated genes. As recent evidence has shown that estrogen replacement therapy is associated with an increased risk of cardiovascular disease, we have studied the effects of genistein, a soy isoflavone with a similar structure to estradiol, on the expression of antioxidant, longevity-related genes. MCF-7 cells (human mammary gland tumor cell line) were incubated for 48 h with 0.5 microM genistein, a concentration found in the plasma of populations consuming diets rich in soy protein. Peroxide levels were determined by fluorimetry, activation of extracellular-signal regulated kinase (ERK1/2), and nuclear factor kappaB (NFkappaB)-signaling pathways by Western blot analysis and ELISA, respectively, and mRNA expression of antioxidant genes by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). Inhibition of basal peroxide levels in MCF-7 cells by genistein was prevented by pretreatment of cells with the estrogen receptor antagonist tamoxifen. Phosphorylation of extracellular regulated kinase (ERK)1/2 led to an activation of NFkappaB, as indicated by increased p50 subunit expression in nuclear extracts, and increased mRNA levels of the antioxidant enzyme manganese-superoxide dismutase (MnSOD). Inhibition of ERK1/2 abrogated genistein-mediated NFkappaB activation and elevated expression of MnSOD. Our molecular studies may provide a basis to determine the effects of genistein and other soy protein-derived products on longevity in both animals and the human population.

Lignan and isoflavone excretion in relation to uterine fibroids: a case-control study of young to middle-aged women in the United States.:Am J Clin Nutr. 2006 Sep;84(3):587-93.Atkinson C, Lampe JW, Scholes D, Chen C, Wahala K, Schwartz SM.Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.[PMID: 16960173]

BACKGROUND: Uterine fibroids are hormonally responsive; estradiol and progesterone stimulate their growth, and gonadotrophin-releasing hormone agonists shrink them. Phytoestrogens, including isoflavones and lignans, can act as weak estrogens or antiestrogens. OBJECTIVE: The objective of this case-control study was to evaluate the relation between uterine fibroid risk and phytoestrogen exposure. DESIGN: Two overnight urine collections (48 h apart) from 170 uterine fibroid cases and 173 controls were analyzed for isoflavonoids (ie, daidzein, genistein, equol, and O-desmethylangolensin) and lignans (enterodiol and enterolactone). Logistic regression was used to determine associations between the mean excretion of the 2 collections and the risk of uterine fibroids. RESULTS: Unadjusted isoflavone excretion did not differ significantly between cases and controls (2.33 +/- 5.82 and 2.60 +/- 5.90 nmol/mg Cr, respectively; P = 0.68), but cases excreted significantly less lignans than did controls (2.86 +/- 3.45 and 4.57 +/- 6.67 nmol/mg Cr, respectively; P < 0.01). The trend for a reduced risk of uterine fibroids with increasing quartiles of lignan excretion was significant (odds ratio for highest versus lowest quartile = 0.31; 95% CI: 0.17, 0.58; P for trend < 0.01). When adjusted for age, BMI, race, family history of uterine fibroids, and isoflavone excretion, this trend remained but was attenuated (P = 0.07). CONCLUSIONS: Our findings suggest a modest inverse association between lignan excretion and uterine fibroid risk. Whether this relation represents an effect of lignans per se or of other constituents of lignan-containing foods on the development of uterine fibroids remains to be determined. No association was found between isoflavone excretion and uterine fibroids; however, the intake of soy foods, the primary source of isoflavones, was low in this population.

Analysis of isoflavones in foods and dietary supplements.:J AOAC Int. 2006 Jul-Aug;89(4):1138-46.Delmonte P, Rader JI. US Food and Drug Administration, Center for Food Safety and Applied Nutrition, Office of Nutritional Products, Labeling and Dietary Supplements, 5100 Paint Branch Pkwy, College Park, MD 20740, USA. pierluigi.delmonte@fda.hhs.gov.[PMID: 16915857]

Isoflavones are phytochemicals found in many plants. Because of their structural similarity to beta-estradiol, health benefits of isoflavones have been evaluated in age-related and hormone-dependent diseases. Daidzein, genistein, and glycitein are present as free forms or derivatives in foods containing soy or soy protein extracts. The analysis of isoflavones has become more complex, because preparations contain isoflavones from multiple sources (e.g., red clover, kudzu). Red clover contains primarily formononetin and biochanin A, while kudzu extracts, which are becoming increasingly common in dietary supplements, contain puerarin and daidzein, among other components. Isoflavones are present in foods and dietary supplements as free compounds, glucoside derivatives, 6"-O-malonyl-7-O-beta-D-glucoside derivatives, and 6"-O-acetyl-7-O-beta-D-glucoside derivatives. High-performance liquid chromatography (HPLC)/tandem mass spectrometry has been applied to the identification of isoflavone derivatives based on the fragmentation pattern of the parent ion, providing high selectivity and sensitivity in the quantitation of isoflavones in complex mixtures. HPLC with ultraviolet detection is often chosen for routine analysis, but a preliminary acid or basic hydrolysis of isoflavone derivatives is often required for the investigation of samples containing extracts from multiple sources. Several internal standards have been used in the analysis of isoflavones from a single botanical source (e.g., soy, red clover), but the identification of a general internal standard remains a challenging process.

Thermal degradation kinetics of isoflavone aglycones from soy and red clover.:Mol Nutr Food Res. 2006 Apr;50(4-5):373-7.Stintzing FC, Hoffmann M, Carle R. Institute of Food Technology, Plant Foodstuff Technology, Hohenheim University, Stuttgart, Germany. stintzin@uni-hohenheim.de.[PMID: 16598813]

Driven by their beneficial effects on human metabolism, isoflavonoids have gained considerable importance reflected by an increased number of isoflavone-rich foods, food supplements and pharmaceutical products on the market, mainly derived from soy and red clover. While it is well known that the genuine isoflavone pattern will be altered during processing, data on aglycone stability are rare. Therefore, a thorough study into the thermal sensitivities of biochanin A, daidzein, formononetin, flavone, genistein, glycitein and isoflavone was performed. Samples were heated at 150 degrees C over a period of 7 h at three different pH values, and degradation of the aglycones was monitored by HPLC-DAD analyses. Therefrom, structure-related stability characteristics could be established. While virtually no decay was observed at pH 7.0 and 5.6, degradation was most prominent at pH 3. 1. Individual aglycone retention was further dependent on heating time with daidzein being the most labile compound after any time interval. Curve fitting of the data revealed first-order degradation kinetics for flavone and glycitein, while the remaining aglycones exhibited a sigmoidal degradation pattern.

Development and validation of a RP-HPLC method for quantification of isoflavone aglycones in hydrolyzed soy dry extracts.: J Chromatogr B Analyt Technol Biomed Life Sci. 2006 May 19;836(1-2):74-8. Epub 2006 Apr 3.Cesar Ida C, Braga FC, Soares CD, Nunan Ede A, Pianetti GA, Condessa FA, Barbosa TA, Campos LM.Department of Pharmaceutical Products, Faculty of Pharmacy, Universidade Federal de Minas Gerais, 31270-901 Belo Horizonte, MG, Brazil. isaccesar@bol.com.br.[PMID: 16595194]

Isoflavones are widely used as an alternative treatment to hormone replacement therapy and also for prevention of several chronic diseases, including cancers. Genistein, daidzein and glycitein are the most abundant isoflavone aglycones found in soy extracts, where they also occur as glycosides. This paper describes the development and validation of an isocratic reversed-phase HPLC (RP-HPLC) method for the analysis of isoflavone aglycones, released after acid hydrolysis of soy dry extracts, used as pharmaceutical raw material. The quantification was carried out in a C(18) endcapped column, using a mobile phase composed of 0.1% acetic acid and methanol (52:48), at a flow rate of 1.0 ml/min and diode array detection (DAD) at 254 nm. The method showed to be linear (r(2)>0.99), precise (R.S.D.<2%), accurate (recovery of 98.88% for daidzein and 98.12% for genistein), robust and specific.

Isoflavones made simple - genistein's agonist activity for the beta-type estrogen receptor mediates their health benefits.:Med Hypotheses. 2006;66(6):1093-114. Epub 2006 Mar 2.McCarty MF.Natural Alternatives International, San Marcos, CA 92078, USA. mccarty@pantox.com

Soy isoflavones, the focus of much research and controversy, are often referred to as "weak estrogens". In fact, genistein is a relatively potent agonist for the recently characterized beta isoform of the estrogen receptor (ERbeta). The low nanomolar serum concentrations of unconjugated free genistein achieved with high-nutritional intakes of soy isoflavones are near the binding affinity of genistein for this receptor, but are about an order of magnitude lower than genistein's affinity for the "classical" alpha isoform of the estrogen receptor (ERalpha). Moreover, these concentrations are far too low to inhibit tyrosine kinases or topoisomerase II, in vitro activities of genistein often cited as potential mediators of its physiological effects. The thesis that these physiological effects are in fact mediated by ERbeta activation provides a satisfying rationale for genistein's clinical activities. Hepatocytes do not express ERbeta; this explains why soy isoflavones, unlike oral estrogen, neither modify serum lipids nor provoke the prothrombotic effects associated with increased risk for thromboembolic disorders. The lack of uterotrophic activity of soy isoflavones reflects the fact that ERalpha is the exclusive mediator of estrogen's impact in this regard. Vascular endothelium expresses both ERalpha and ERbeta, each of which has the potential to induce and activate nitric oxide synthase; this may account for the favorable influence of soy isoflavones on endothelial function in postmenopausal women and ovariectomized rats. The ERbeta expressed in osteoblasts may mediate the reported beneficial impact of soy isoflavones on bone metabolism. Suggestive evidence that soy-rich diets decrease prostate cancer risk, accords well with the observation that ERbeta appears to play an antiproliferative role in healthy prostate. In the breast, ERalpha promotes epithelial proliferation, whereas ERbeta has a restraining influence in this regard - consistent with the emerging view that soy isoflavones do not increase breast cancer risk, and possibly may diminish it. Premenopausal women enjoy a relative protection from kidney failure; since ERbeta is an antagonist of TGF-beta signaling in mesangial cells, soy isoflavones may have nephroprotective potential. Estrogen also appears to protect women from left ventricular hypertrophy, and recent evidence suggests that this effect is mediated by ERbeta. In conjunction with reports that isoflavones may have a modestly beneficial impact on menopausal symptoms - perhaps reflecting the presence of ERbeta in the hypothalamus - these considerations suggest that soy isoflavone regimens of sufficient potency may represent a safe and moderately effective alternative to HRT in postmenopausal women. Further clinical research is required to characterize the impact of optimal genistein intakes on endothelial and bone function in men. Studies with ERbeta-knockout mice could be helpful for clarifying whether ERbeta does indeed mediate the chief physiological effects of low nanomolar genistein. S-equol, a bacterial metabolite of daidzein, has an affinity for ERbeta nearly as high as that of genistein; whether this compound contributes meaningfully to the physiological efficacy of soy isoflavones in some individuals is still unclear.

Genistein, a natural product from soy, is a potent inhibitor of transthyretin amyloidosis.:Proc Natl Acad Sci U S A. 2005 Oct 11;102(41):14545-50. Epub 2005 Sep 29.Green NS, Foss TR, Kelly JW.Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, BCC265, La Jolla, CA 92037, USA.[PMID: 16195386]

The misfolding of transthyretin (TTR), including rate-limiting tetramer dissociation and partial monomer denaturation, is sufficient for TTR misassembly into amyloid and other abnormal quaternary structures associated with three amyloid diseases: senile systemic amyloidosis, familial amyloid polyneuropathy, and familial amyloid cardiomyopathy. Small molecules can bind to one or both of the unoccupied TTR thyroid hormone-binding sites, stabilizing the native tetramer more than the dissociative transition state, thereby raising the kinetic barrier for tetramer dissociation. Herein we demonstrate that genistein, the major isoflavone natural product in soy, works in this fashion and is an excellent inhibitor of transthyretin tetramer dissociation and amyloidogenesis, reducing acid-mediated fibril formation to <10% of that exhibited by TTR alone. Genistein also inhibits the amyloidogenesis of the most common familial amyloid polyneuropathy and familial amyloid cardiomyopathy mutations in TTR: V30M and V122I, respectively. Genistein additionally inhibits tetramer dissociation under physiological conditions thought to lead to slow amyloidogenesis in humans. Furthermore, this natural product exhibits highly selective binding to TTR in plasma over all of the other plasma proteins. Isothermal titration calorimetry shows that genistein binds to TTR with negative cooperativity (K(d1) = 40 nM, K(d2) = 1.4 microM). The benefits of using a nutraceutical such as genistein to treat orphan diseases such as the TTR amyloidoses include known oral bioavailability and safety data. It is conceivable that some patients could benefit from simply increasing their intake of soy products or supplements.

Quantitative determination and structural characterization of isoflavones in nutrition supplements by liquid chromatography-mass spectrometry.:J Chromatogr A. 2005 Jul 29;1082(1):60-70.Chen LJ, Zhao X, Plummer S, Tang J, Games DE.Division of Cancer Biotherapy, State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.

In this paper, an accurate and route method was developed to quantitative determine daidzein, genistein, glycitein, daidzin, glycitin, 6"-O-acetyldaidzin, 6"-O-acetylglycitin and 6"-O-acetylgenistin contents in selected high and low isoflavones in nutrition supplements by on line liquid chromatography-atmospheric pressure chemical ionisation mass spectrometry (LC-APCI-MS). Improved extraction and hydrolysis methods of the isoflavones from three nutrition supplements were also studied and a rapid extraction method was developed. Comparison of different MS2 and MS3 spectra of isoflavones and some unknown compounds were also explored and proposed pathway fragments of nine isoflavones were first systematically suggested.

Topical application of Bifidobacterium-fermented soy milk extract containing genistein and daidzein improves rheological and physiological properties of skin.:J Cosmet Sci. 2004 Sep-Oct;55(5):473-9.

The authors examined the effects of Bifidobacterium-fermented soy milk extract (BE) containing genistein and daidzein on the hyaluronic acid (HA) content and rheological and physiological properties of hairless mouse and/or human skin. Topical application of BE for six weeks significantly restored changes in the elasticity and viscoelasticity of mouse skin, increased the HA content, and hydrated and thickened mouse skin. Also, topical application of a gel formula containing 10% BE to the human forearm for three months significantly lessened the decrease in skin elasticity. Therefore, BE is expected to become a new cosmetic ingredient to prevent the loss of skin elasticity through enhancement of HA production.

Determination of soybean isoflavones in foods by HPLC:Sichuan Da Xue Xue Bao Yi Xue Ban. 2003 Jan;34(1):151-4.Mi J, Li Y, Zeng H, Zhang J. Department of Sanitary Technology, West China School of Public Health, Sichuan University, Chengdu 610041, China.

OBJECTIVE: To establish a method for the determination of soybean isoflavones including daidzein and genistein in foods by high performance liquid chromatography. METHODS: Soybean isoflavones in food samples were refluxed and extracted by 0.5 mol/L hydrochloric acid and ethanol. Soybean isoflavones were chromatographically separated on a C18 column with a mobile phase consisting of methanol and 0.01 mol/L ammonium acetate buffer solution (pH 4.5) (60 + 40), and then detected at 254 nm with ultraviolet-visible detector. RESULTS: The detection limits were 0.05 microg/ml for daidzein and 0.04 microg/ml for genistein, respectively. The spiked recoveries of the samples were 91.4%-113.1%. The within-day and between-day (n = 6) relative standard deviations were 1.1%-2.8% and 2.9%-5.1%, respectively. CONCLUSION: The method is simple, sensitive and applicable to the determination of soybean isoflavones in foods. It also provides an analytical method for isoflavones in functional food and the absorption of phytoextrogens from foods.

Dermatological Application of Soy Isoflavones to Prevent Skin Ageing in Postmenopausal Women:

Isoflavones from soy beans are used in functional food products as a measure to alleviate hormone-dependent physiological disorders such as postmenopausal symptoms, osteoporosis and cardiovascular problems. These natural phytohormones are well perceived and do not show the negative side effects found in conventional therapies with hormones such as estrogens. A number of studies show that estrogens can slow down the aging process of the skin in postmenopausal women. For this reason, isoflavones from soy beans are also very interesting compounds for cosmetic formulations. We succeeded in isolating very pure fractions of isoflavones in the form of the active aglycones suitable for cosmetic applications. We herein report the use of this aglycone preparation in the treatment of post menopause skin and discuss further applications.
Phytoestrogens are plant derived compounds with biological activities comparable to the human hormone estrogen
Epidemiological studies indicating associations between diet and disease states led to the investigation of a series of bioactive plant compounds, called phytochemicals. Some of these nonnutrient plant chemicals, such as phytoestrogens were shown to confer significant long-term health benefits. Phytoestrogens are structurally and functionally similar to human estrogen (Fig. 1). There are two types of phytoestrogens, the lignans and the isoflavones. Soybeans are especially rich in isoflavones. They contain the isoflavones genistein and daidzein and their respective b-glycosides,
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Benefits of phytoestrogens in skin care:

After menopause, the skin undergoes changes that include thinning, decrease in elasticity and wrinkle formation (Bolognia et al. 1989). This abrupt skin aging is the consequence of a lower production of collagen and elastin, the supportive and elastic proteins of the skin (Brincat et al. 1987, Affinito et al. 1999, Adamiak et al. 2000). Thus, the skin appears to be an organ responding to ovarian hormones. Indeed estrogen receptors have been identified in human skin (Hasselquist et al. 1980, Schmidt et al. 1990). The question as to how far this skin aging is induced by postmenopausal hypoestrogenism is still under discussion (Affinito et al. 1999).
Several studies show that estrogen therapy preserves collagen content, elastic properties, and thickness of the skin in postmenopausal women (Hasselquist et al. 1980, Punnonen et al. 1987, Castelo-Branco et al. 1992, Dunn et al. 1997). Topical estrogen treatments were shown to reverse postmenopausal skin aging (Callens et al. 1996, Schmidt et al. 1996). Estrogenic compounds reduce the depth of wrinkles and increase the tone and hydration of the skin.
Since the results obtained with isoflavone supplemented nutraceuticals are very positive, we believe that the topical application of phytohormones can also fight some of the menopause-associated skin problems. In in vitro testing genistein stimulated collagen synthesis (Kawashima et al. 1996) and down regulated matrix metalloproteinases (Shao et al.). Therefore topical application of isoflavones is not only beneficial in postmenopausal skin, where it replenishes the loss of endogenous estrogen but also in normal skin when used to treat cellulite or dull skin in general.

Development of a pure isoflavone preparation suitable for skin care:

There are several soy isoflavone products on the market that are sold as dietary food supplements. In most cases, these food supplements contain only isoflavone glycosides, the molecular form that is biologically not active. However, after ingestion the glycosides are transformed by intestinal glucosidases and intestinal bacterial metabolism into the estrogenically active form (Setchell and Cassidy 1999). Since the skin does not habour such bacteria and enzymes, the active isoflavone preparations for skin care must be in the form of aclycones. Unfortunately, these aglycones have a poor solubility in water and oil. Thus, a special galenic form is necessary to introduce these isoflavone preparations into cosmetic formulations.
We developed a process to prepare a pure isoflavones suitable for cosmetic applications.
A soy preparation which is rich in isoflavones is treated with a bglucosidase to deglycosylate the isolflavones to the corresponding aglycones. As a consequence of their hydrophobic nature, these aglycones precipitate almost entirely and can be separated by centrifugation from the enzyme and the water-soluble brown polyphenols. The aglycones are extracted with alcohol to get a phytohormone solution. The aglycones can then be incorporated into liposomes to get a water dispersable preparation which has a high bioavailability in the skin.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Application of soy isoflavone aglycones in cosmetic formulations:

Over the last decade, plant derived ingredients have gained a lot of interest in cosmetic formulations. However, in many cases, these products do not offer the proposed activity since the preparations do not contain the active molecules in an appropriate concentration or the compounds are not bioavailable. The described liposomal aglycone preparation is a new active ingredient derived from soy. The preparation contains the active form of isoflavones in a high concentration and offers a number of different cosmetic and dermatological applications.
Oral and topical estrogen applications have shown to preserve collagen content, elastic properties, and thickness of the skin in postmenopausal women (Dunn et al. 1997, Schmidt et al. 1996). However, human hormones cannot be used in cosmetic formulations and due to the potential adverse effects should only be considered in severe cases in dermatological products. The treatment of skin during and after menopause with an active aglycone preparation from soy is a completly new approach in the battle against the aging process in the skin. The loss of hormonal activity reduces the skin tone and its hydration. This deterioration is based on the reduction of the metabolic activity of skin cells and results in wrinkles and dry skin.
Isoflavones aglycones encapsulated into liposomes can be applied in different formulations such as gels, lotions and creams since the product can easily be formulated into the water phase of cosmetics. A combination with moisturizers and classical anti-aging ingredients, such as vitamins and antioxidants may even further improve the activity of the product.
It is evident, that isoflavones are also very interesting compounds for anti-cellulite products as they enhance the skin tone and its viscoelastic properties. Thus, we use our aglycone preparation in the respective field. In our products, we combined the phytohormones with an algae extract (spirulina platensis) which is rich in minerals to achieve a highly efficient anti-cellulite formulation suitable to treat hormone dependent skin and subcutis problems (Z¨¹lli et al. 2001).
The anti-breast cancer properties of soy isoflavones have been reported (Setchell and Cassidy 1999). But only little data exist about the effects of soy isoflavones on histologically normal human breast. In one of these very intersting studies McMichael-Phillips et al. 1998 found that phytoestrogens can stimulate the proliferation of breast epithelium significantly in vivo based on higher serum levels of genistein and daidzein after soy supplementation. Thus the application of liposomal aglycones in breast firming products is a new opportunity to improve skin tone and elasticity in women of all ages.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Structural Formula:

	R1	R2	R3
[Glycoside] Daidzin Glycitin Genistin 6"-0-malonyldaizin 6"-0-malonylglycitin 6"-0-malonylgenistin 6"-0-acetyldaizin 6"-0-acetylglycitin 6"-0-acetylgenistin	H H H COCH2COOH COCH2COOH COCH2COOH COCH3 COCH3 COCH3	H OCH3 H H OCH3 H H OCH3 H	H H OH H H OH H H OH
[Non-glycoside] Daidzein Glycitein Genistein	H H H	H OCH3 H	H H OH

Soy Isoflavones Metabolism:

The biological effects of soy isoflavones are strongly influenced by their metabolism, which is dependent on the activity of bacteria that colonize the human intestine. For example, the soy isoflavone daidzein may be metabolized to equol, a metabolite that has greater estrogenic activity than daidzein, and to other metabolites that are less estrogenic.
Studies that measure urinary equol excretion after soy consumption indicate that only about 33% of individuals from Western populations metabolize daidzein to equol. Thus, individual differences in the metabolism of isoflavones could have important implications for the biological activities of these phytoestrogens.
Soy Bean Isoflavone is called "Phytoestrogen", because its chemical structure is similar to that of the female hormone estrogen. It is considered to act like a weak female hormone in the body.

Soy Isoflavones Estrogenic and Anti-Estrogenic Activities:

Soy isoflavones are known to have weak estrogenic activity. Estrogens are signaling molecules that exert their effects by binding to estrogen receptors within cells (chemical structures of endogenous estrogens). The estrogen-receptor complex interacts with DNA to change the expression of estrogen-responsive genes. Estrogen receptors are present in numerous tissues other than those associated with reproduction, including bone, liver, heart and brain. Soy isoflavones and other phytoestrogens can bind to estrogen receptors, mimicking the effects of estrogen in some tissues and antagonizing (blocking) the effects of estrogen in others. Scientists are interested in the tissue-selective activities of phytoestrogens because anti-estrogenic effects in reproductive tissue could help reduce the risk of hormone associated cancers (breast, uterine and prostate), while estrogenic effects in other tissues could help maintain bone density and improve blood lipid profiles (cholesterol levels). The extent to which soy isoflavones exert estrogenic and anti-estrogenic effects in humans is currently the focus of considerable scientific research.
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Soy Isoflavones Estrogen Receptor-Independent Activities:

Soy isoflavones and their metabolites also have biological activities that are unrelated to their interactions with estrogen receptors. By inhibiting the synthesis and activity of certain enzymes involved in estrogen metabolism, soy isoflavones may alter the biological activity of endogenous estrogens and testosterones. Soy isoflavones have also been found to inhibit tyrosine kinases, enzymes that play critical roles in the signaling pathways that stimulate cell proliferation. Additionally, isoflavones can act as antioxidants in vitro, but the extent to which they contribute to the antioxidant status of humans is not yet clear. Plasma F2-isoprostanes, biomarkers of lipid peroxidation in vivo, were lower after two weeks of daily consumption of soy protein containing 56 mg of isoflavones than after consumption of soy protein providing only 2 mg of isoflavones. However, daily supplementation with 50-100 mg of isolated soy isoflavones did not significantly alter plasma or urinary F2-isoprostane levels.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Soy Isoflavones Prevent Cardiovascular Disease:

Serum Cholesterol:

The results of numerous controlled clinical trials in Western populations suggest that increasing soy isoflavone intake, particularly by substituting soy protein for animal protein, decreases cardiovascular risk by lowering serum total and LDL cholesterol concentrations. Substituting 25-50 g/d of soy protein for animal protein in the diet has been found to lower serum LDL-cholesterol by about 8% in adults with elevated serum cholesterol levels. There is some evidence that soy protein containing isoflavones is more effective than soy protein without isoflavones in lowering LDL cholesterol, but the consumption of soy isoflavones alone (as supplements or extracts) does not appear to be as effective in lowering serum cholesterol as intact soy protein that contains isoflavones and other phytochemicals. For more information on soy protein and cholesterol, see the article on Legumes.

Effects on Arterial Function:

The preservation of normal arterial function plays an important role in cardiovascular disease prevention. The ability of arteries to dilate in response to nitric oxide produced by the endothelial cells that line their inner surface (endothelium-mediated vasodilation) is compromised in people at high risk for cardiovascular disease. However, most placebo-controlled trials found no significant improvement in endothelium-mediated vasodilation when postmenopausal women were supplemented with up to 80 mg/d of soy isoflavones or up to 60 g/d of soy protein containing isoflavones. Measures of arterial stiffness assess the distensibility of arteries, and a strong association between arterial stiffness and atherosclerosis has been observed. In placebo-controlled clinical trials, supplementation of postmenopausal women with 80 mg/d of a soy isoflavone extract for 5 weeks significantly decreased arterial stiffness, as did supplementation of men and postmenopausal women with 40 g/d of soy protein providing 118 mg/d of soy isoflavones for 3 months. Although most studies have not found supplementation with soy protein or isoflavones to improve endothelium-mediated vasodilation, preliminary research suggests that soy isoflavone supplementation may decrease arterial stiffness.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Soy Isoflavones and Hormone-associated Cancers:

Breast Cancer:

Breast cancer rates in Asia, where average isoflavone intakes from soy foods range from 11-47 mg/d, are lower than breast cancer rates in the Western countries where average isoflavone intakes in non-Asian women may be less than 2 mg/d. However, many other hereditary and lifestyle factors could contribute to this difference in breast cancer rates. Most epidemiological studies have not found that women with higher soy intakes are at lower risk of breast cancer, with the possible exception of women who had higher soy intakes during adolescence. At present, there is no evidence that taking soy isoflavone supplements decreases breast cancer risk. See the article on Legumes for more information about soy consumption and breast cancer risk.

Endometrial Cancer:

Because the development of endometrial (uterine) cancer is related to prolonged exposure to unopposed estrogens, it has been suggested that high intakes of phytoestrogens with anti-estrogenic activity in uterine tissue could be protective against endometrial cancer. In support of this idea, two retrospective case-control studies found that women with endometrial cancer had lower intakes of soy isoflavones from foods compared to cancer-free control groups. However, supplementation of postmenopausal women with soy protein providing 120 mg/d of isoflavones for 6 months did not prevent endometrial hyperplasia induced by the administration of exogenous estradiol. Although limited evidence from case-control studies suggests that higher dietary intakes of soy foods may be associated with lower endometrial cancer risk, there is no evidence that taking soy isoflavone supplements decreases endometrial cancer risk.

Prostate Cancer:

Mortality from prostate cancer is much higher in the US than in Asian countries, such as China. However, epidemiological studies do not provide consistent evidence that high intakes of soy foods are associated with reduced prostate cancer risk. See the article on Legumes for more information about soy foods and prostate cancer risk. The results of cell culture and animal studies suggest a potential role for soy isoflavones in limiting the progression of prostate cancer. Although soy isoflavone supplementation for up to one year did not significantly decrease serum prostate specific antigen (PSA) concentrations in men without confirmed prostate cancer, soy isoflavone supplementation appeared to slow rising serum PSA concentrations associated with prostate tumor growth in two small studies of prostate cancer patients. Although such preliminary findings are encouraging, the results of larger randomized controlled trials, which are currently ongoing, are needed to determine whether soy isoflavone supplementation can play a role in the prevention or treatment of prostate cancer.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Soy Isoflavones Prevent Osteoporosis:

Although hip fracture rates are generally lower among Asian populations consuming soy foods than among Western populations, it is not yet clear whether increasing soy isoflavone consumption in Western populations helps to prevent osteoporosis. The results of short-term clinical trials (6 months or less) assessing the effects of increased soy intake on biochemical markers of bone formation and bone resorption are inconsistent. While some controlled trials in postmenopausal women found that increasing intakes of soy foods, soy protein or soy isoflavones improved markers of bone resorption and formation, others found no improvement. Randomized controlled trials of longer duration are required to determine whether increased soy intake can actually prevent losses in bone mineral density (BMD) or osteoporotic fracture. Two controlled clinical trials found that BMD losses over 6 months were lower in postmenopausal women supplemented with soy protein containing isoflavones than in those supplemented with equal amounts of milk protein, but two longer trials found that BMD loss did not differ between postmenopausal women supplemented with soy protein containing isoflavones and those supplemented with milk protein.
A 2-year clinical trial found that daily consumption of soy milk containing isoflavones decreased BMD loss in the lumbar spine compared to daily consumption of soymilk without isoflavones, but two others studies found that BMD loss did not differ between postmenopausal women taking soy protein supplements containing isoflavones and those taking soy protein supplements without isoflavones. Loss of bone mineral content at the hip over one year was lower in Taiwanese women who took 80 mg/d of isolated soy isoflavones compared to placebo, but the difference was significant only in those women who were at least 4 years past menopause, had lower body weights or lower calcium intakes. While there is some evidence that isoflavone-rich diets have bone-sparing effects, it is not known whether increasing soy isoflavone intake appreciably decreases the risk of osteoporosis or osteoporotic fracture.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Assessment of soy phytoestrogens' effects on bone turnover indicators in menopausal women with osteopenia in Iran: a before and after clinical trial.:

Background: Osteoporosis is the gradual declining in bone mass with age, leading to increased bone fragility and fractures. Fractures in hip and spine are known to be the most important complication of the disease which leads in the annual mortality rate of 20% and serious morbidity rate of 50%. Menopause is one of the most common risk factors of osteoporosis. After menopause, sex hormone deficiency is associated with increased remodeling rate and negative bone balance, leading to accelerated bone loss and micro-architectural defects, resulting into increased bone fragility. Compounds with estrogen-like biological activity similar to "Isoflavones" present in plants especially soy, may reduce bone loss in postmenopausal women as they are similar in structure to estrogens. This research, therefore, was carried out to study the effects of Iranian soy protein on biochemical indicators of bone metabolism in osteopenic menopausal women.
Materials and Methods: This clinical trial of before-after type was carried out on 15 women 45-64 years of age. Subjects were given 35 g soy protein per day for 12 weeks. Blood and urine sampling, anthropometric measurement and 48-h-dietary recalls were carried out at zero, 6 and 12 weeks. Food consumption data were analyzed using Food Proccessor Software. For the study of bone metabolism indicators and changes in anthropometric data as well as dietary intake, and repeated analyses were employed.
Results: Comparison of weight, BMI, physical activity, energy intake and other intervening nutrients did not reveal any significant changes during different stages of the study. Soy protein consumption resulted in a significant reduction in the urinary deoxypyridinoline and increasing of total alkaline phosphatase (p < 0.05), although the alterations in osteocalcin, c-telopeptide, IGFBP3 and type I collagen telopeptide were not significant.
Conclusion: In view of beneficial effect of soy protein on bone metabolism indicators, inclusion of this relatively inexpensive food in the daily diet of menopausal women, will probably delay bone resorption, thereby preventing osteoporosis.

Soy Isoflavones Help Prevent Cognitive Decline:

Scientific research on the effect of soy isoflavones on cognitive function is limited. The only published observational study that examined the relationship between soy intake and cognitive function found that Hawaiian men who reported consuming tofu at least twice weekly during midlife were more likely to have poor cognitive test scores 20-25 years later than those who reported consuming tofu less than twice a week. In contrast, the results of several small clinical trials in postmenopausal women suggest that increasing soy isoflavone intake may result in modest improvements in performance on some cognitive tests for up to six months. Postmenopausal women given soy extracts providing 60 mg/d of soy isoflavones for 6-12 weeks performed better than women given a placebo on cognitive tests of picture recall (short-term memory), learning rule reversals (mental flexibility) and a planning task. In a longer trial, postmenopausal women given supplements that provided 110 mg/d of soy isoflavones for six months performed better than women given placebos on a test of verbal fluency.

However, in the largest placebo-controlled trial in postmenopausal women to date, daily intake of soy protein providing 99 mg of isoflavones for one year did not affect performance on a battery of cognitive function tests, including tests for memory, attention, verbal fluency and dementia.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Soy Isoflavones Treatment Menopausal Symptoms:

Hot flushes (flashes) are the primary reason that women seek medical attention for menopausal symptoms. Concern over potential adverse effects of hormone replacement therapy has led to increased interest in the use of phytoestrogen supplements by women experiencing menopausal symptoms. The effects of increasing soy isoflavone intake on the frequency of hot flushes have been examined in a number of randomized controlled trials. Out of 8 randomized controlled trials of soy foods, only one found a significant reduction in the frequency of hot flushes, while 3 out of 5 controlled trials of soy isoflavone extracts reported a significant reduction in hot flush frequency.
In general, any reductions observed were modest (10-20%) compared to placebo. Breast cancer survivors in particular may experience more frequent and severe hot flushes related to therapies aimed at preventing breast cancer recurrence. However, none of the randomized controlled trials in breast cancer survivors found that soy isoflavone supplementation was significantly more effective than a placebo in decreasing the frequency or severity of hot flushes. Overall, there is little evidence that increasing soy isoflavone intake from food or supplements substantially improves menopausal hot flushes.
soy isoflavones,Genistein 90%98%M.F.C15 H10O5.CAS.NO:446-72-0,Daidzein 98%M.F.C15 H10O4.CAS.NO:486-66-8.soy isoflavone,Glycine max L.extract photo picture image

Soy isoflavone glycitein protects against beta amyloid-induced toxicity and oxidative stress in transgenic Caenorhabditis elegans:

Background: Epidemiological studies have associated estrogen replacement therapy with a lower risk of developing Alzheimer's disease, but a higher risk of developing breast cancer and certain cardiovascular disorders. The neuroprotective effect of estrogen prompted us to determine potential therapeutic impact of soy-derived estrogenic compounds. Transgenic C. elegans, that express human beta amyloid (Abeta), were fed with soy derived isoflavones genistein, daidzein and glycitein (100 microg/ml) and then examined for Abeta-induced paralysis and the levels of reactive oxygen species.
Results: Among the three compounds tested, only glycitein alleviated Abeta expression-induced paralysis in the transgenic C. elegans. This activity of glycitein correlated with a reduced level of hydrogen peroxide in the transgenic C. elegans. In vitro scavenging effects of glycitein on three types of reactive oxygen species confirmed its antioxidant properties. Furthermore, the transgenic C. elegans fed with glycitein exhibited reduced formation of beta amyloid.
Conclusion: These findings suggest that a specific soy isoflavone glycitein may suppress Abeta toxicity through combined antioxidative activity and inhibition of Abeta deposition, thus may have therapeutic potential for prevention of Abeta associated neurodegenerative disorders.

Pharmacokinetics of isoflavones, daidzein and genistein, after ingestion of soy beverage compared with soy extract capsules in postmenopausal Thai women.:

Background: Isoflavones from soybeans may provide some beneficial impacts on postmenopausal health. The purpose of this study was to compare the pharmacokinetics and bioavailability of plasma isoflavones (daidzein and genistein) after a single dose of orally administered soy beverage and soy extract capsules in postmenopausal Thai women.
Methods: We conducted a randomized two-phase crossover pharmacokinetic study in 12 postmenopausal Thai women. In the first phase, each subject randomly received either 2 soy extract capsules (containing daidzin : genistin = 7.79 : 22.57 mg), or soy beverage prepared from 15 g of soy flour (containing daidzin : genistin = 9.27 : 10.51 mg). In the second phase, the subjects received an alternative preparation in the same manner after a washout period of at least 1 week. Blood samples were collected immediately before and at 0.5, 1, 2, 4, 6, 8, 10, 12, 24 and 32 h after administration of the soy preparation in each phase. Plasma daidzein and genistein concentrations were determined by using high performance liquid chromatography (HPLC). The pharmacokinetic parameters of daidzein and genistein, i.e. maximal plasma concentration (Cmax), time to maximal plasma concentration (Tmax), area under the plasma concentration-time curve (AUC) and half-life (t1/2), were estimated using the TopFit version 2.0 software with noncompartmental model analysis.
Results: There were no significant differences in the mean values of Cmax/dose, AUC0-32/dose, AUC0- proportional, variant/dose, Tmax, and t1/2 of genistein between both preparations. For pharmacokinetic parameters of daidzein, the mean values of Cmax/dose, Tmax, and t1/2 did not significantly differ between both preparations. Nonetheless, the mean AUC0-32/dose and AUC0- proportional, variant/dose after administration of soy extract capsules were slightly (but significantly, p < 0.05) higher than those of soy beverage.
Conclusion: The bioavailability of daidzein, which was adjusted for the administered dose (AUC/dose), following a single oral administration of soy beverage was slightly (but significantly) less than that of soy extract capsules, whereas, the bioavailability adjusted for administered dose of genistein from both soy preparations were comparable. The other pharmacokinetic parameters of daidzein and genistein, including Cmax adjusted for the dose, Tmax and t1/2, were not different between both soy preparations.

Scientific References:

1.Research Update:Genistein:4',5,7-Trihydroxyisoflavone.:Introduction and Its Benefit Applications.

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And as it happens,the technique of imitation,along with the production of the simulacrum,has always been in Plato's eyes manifestly magical,thaumaturgical:......and the same things appear bent and straight to those who view them in water and out,or concave and convex,owing to similar errors of vision about colors, and there is obviously every confusion of this sort in our souls.And so scene painting (skiagraphia) in its exploitation of this weakness of four nature falls nothing short of witchcraft (thaumatopoia), and so do jugglery and many other such contrivances.(Republic X,602c-d;cf.also 607c).