Phytoestrogen in soy

Equols are isoflavandiols formed by reduction of soy isoflavones such as daidzein and genistein by gut microorganisms. These phytoestrogens are of interest for their various biological effects. We report biosynthesis from genistein to (-)-5-hydroxy-equol in recombinant E. coli expressing three reductases (daidzein reductase DZNR, dihidrodaidzein reductase DHDR, tetrahydrodaidzein reductase THDR) and a racemase (dihydrodaidzein racemase, DDRC) originating from the gut bacterium, Slackia isoflavoniconvertens...

Genistein is a phytoestrogen found in soy and soy-based products. Previously, we found that genistein adversely affected estradiol levels and follicle growth in vitro. Proper hormone production and follicle growth are key regulators of normal fertility. Therefore, we hypothesized that genistein adversely affects female fertility and pregnancy outcomes. To test this hypothesis, we dosed sexually mature female CD-1 mice (35days) with 0, 300, 500, or 1000ppm genistein for 30, 60, 150, and 240days. At the end of the dosing periods, we measured mating rate, pregnancy rate, fertility rate, gestation time, parturition time, pup mortality, litter size, average pup weight, and estradiol and progesterone levels...

Although soy phytoestrogen are proposed to prevent or improve postmenopausal vascular and bone diseases, the currently available data are controversial and unclear. In this study we evaluated the molecular and biochemical action of genistein on the cellular events involved in vascular calcification. Rat monocytes, aortic vascular cell and osteoblasts cultures in vitro exposed to Gen were employed. Gen down regulated the expression of cell adhesion molecules involved in stable leukocyte attachment. Using flow cytometry we found that the PE significantly diminished monocyte integrins CD11b, CD11c and CD18 expression either under basal and pro-inflammatory environment...

Recent evidence indicates that resveratrol, a phytoestrogen, can improve cognitive function in postmenopausal women by enhancing cerebral vasodilator responsiveness. We examine the effects of phytoestrogen supplementation on cognition and compare resveratrol with other phytoestrogens. Databases were searched for reports of randomized controlled trials (RCTs) containing terms describing phytoestrogens together with terms relating to cognition. Effect sizes were determined for changes in cognition. We identified 23 RCTs, 15 with isoflavone and eight with resveratrol or grape formulations...

Breast cancer is the deadliest neoplasm in women globally, resulting in a significant health burden. In many cases, breast cancer becomes resistant to chemotherapy, radiation, and hormonal therapies. It is believed that genetics is not the major cause of breast cancer. Other contributing risk factors include age at first childbirth, age at menarche, age at menopause, use of oral contraceptives, race and ethnicity, and diet. Diet has been shown to influence breast cancer incidence, recurrence, and prognosis...

BACKGROUND: Our previous studies demonstrated that growth and migration of medulloblastoma (MB), the most common malignant brain tumor in children, are stimulated by 17β-estradiol. The growth stimulating effects of estrogens are mediated through ERβ and insulin-like growth factor 1 signaling to inhibit caspase 3 activity and reduce tumor cell apoptosis. The objective of this study was to determine whether estrogens decreased sensitivity of MB cells to cytotoxic actions of chemotherapeutic drugs...

Phytoestrogen-rich soy is known to ameliorate menopause-associated obesity and metabolic dysfunction for reasons that are unclear. The gut microbiota have been linked with the development of obesity and metabolic dysfunction. We aimed to determine the impact of soy on cardiometabolic health, adipose tissue inflammation, and the cecal microbiota in ovariectomized (OVX) rats bred for low-running capacity (LCR), a model that has been previously shown to mimic human menopause compared to sham-operated (SHM) intact control LCR rats...

Endocrine disrupting chemicals (EDCs) are chemicals that interfere with the organizational or activational effects of hormones. Although the vast majority of the EDC literature focuses on steroid hormone signaling related impacts, growing evidence from a myriad of species reveals that the nonapeptide hormones vasopressin (AVP) and oxytocin (OT) may also be EDC targets. EDCs shown to alter pathways and behaviors coordinated by AVP and/or OT include the plastics component bisphenol A (BPA), the soy phytoestrogen genistein (GEN), and various flame retardants...

The course and severity of lupus in spontaneous murine lupus models varies among laboratories, which may be due to variations in diet, housing and/or local environmental conditions. In this study, we investigated the influence of common rodent diets while keeping other factors constant. Female lupus-prone MRL/lpr (MRL/MpJ-Faslpr/J) mice were subjected to the same housing conditions and given one of the three diets: Teklad 7013 containing isoflavone-rich soy and alfalfa, Harlan 2018 isoflavone-rich soy-based diet or Research Diets Inc...

BACKGROUND AND PURPOSE: The in vivo oestrogenicity of genistein and its glycoside genistin is still under debate. The present study aimed to develop a physiologically based kinetic (PBK) model that provides insight in dose-dependent plasma concentrations of genistein aglycone and its metabolites and enables prediction of in vivo oestrogenic effective dose levels of genistein and genistin in humans. EXPERIMENTAL APPROACH: A PBK model for genistein and genistin in humans was developed based on in vitro metabolic parameters...

Phytoestrogens are polyphenol, non-steroidal substances of plant origin, resembling 17β-estradiol in structure. These substances can act as either agonists or antagonists of oestrogen receptors α and β. Phytoestrogens are widely used to alleviate menopausal symptoms, such as hot flushes and night sweats. Most of the currently available products of plant origin registered to soften climacteric symptoms consist of extracts obtained from soy, red clover, or black cohosh. Non-hormonal phytotherapy is a new alternative for patients suffering from menopausal symptoms...

OBJECTIVE: The objective of this study is to compare the effects of topical estrogen and genistein (a soy isoflavone) on the facial skin collagen of postmenopausal women not undergoing systemic hormonal therapy. METHODS: This is a prospective, double blind, randomized, controlled clinical trial. Volunteer women (N = 30) 45-55 year old from the Endocrine Gynecology sector of the Gynecology Department of the Federal University of São Paulo (UNIFESP). The Ethical Committee of the Federal University of São Paulo approved the study (report no...

Although studies have linked soy phytoestrogen 4,7,4-trihydroxyisoflavone genistein (GEN) to reduced type 1 diabetes (T1D) risk, the mechanism of dietary GEN on T1D remains unknown. In our studies, adult non-obese diabetic (NOD) mouse model was employed to investigate the effects of GEN exposure on blood glucose level (BGL), glucose tolerance, gut microbiome, and immune responses. Adult male and female NOD mice were fed with either soy-based or casein-based diet, and received GEN at 20mg/kg body weight by gavage daily...

OBJECTIVE: To verify the efficacy of phytoestrogen supplementation combined with aerobic and resistance training on the improvement of climacteric symptoms and health-related quality of life (HRQoL) in postmenopausal women. METHODS: From a pool of women who had participated in a 1-year intervention study and were randomly assigned to either exercise + phytoestrogen (EX + PHY) or exercise + placebo (EX + PL), a total of 31 healthy but overweight women (mean age 59...

Estrogen deficiency has been well characterized in inflammatory disorders including neuroinflammation. Daidzein, a dietary alternative phytoestrogen found in soy (Glycine max) as primary isoflavones, possess anti-inflammatory activity, but the effect of its active metabolite Equol (7-hydroxy-3-(4'-hydroxyphenyl)-chroman) has not been well established. In this study, we investigated the anti-neuroinflammatory and neuroprotective effect of Equol in vitro. To evaluate the potential effects of Equol, three major types of central nervous system (CNS) cells, including microglia (BV-2), astrocytes (C6), and neurons (N2a), were used...

BACKGROUND: Soy foods possess both antiestrogenic and estrogen-like properties. It remains controversial whether women diagnosed with breast cancer should be advised to eat more or less soy foods, especially for those who receive hormone therapies as part of cancer treatment. METHODS: The association of dietary intake of isoflavone, the major phytoestrogen in soy, with all-cause mortality was examined in 6235 women with breast cancer enrolled in the Breast Cancer Family Registry...

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BACKGROUND: Obese, type two diabetics are at an increased risk for fracturing their limb bones in comparison to the general population. Phytoestrogens like as the soy isoflavone genistein have been shown to protect against bone loss. In this study, we tested the effects of genistein treatment on femurs of ob/ob mice, a model for obesity and type two diabetes mellitus. METHODS: Twenty six-week-old female mice were divided into obese (ob/ob) control, obese genistein-treated, lean (ob/+) control, and lean genistein-treated groups (n = 5 each)...

BACKGROUND: Phytoestrogens such as genistein, the most prominent isoflavone from soy, show concentration-dependent anti-estrogenic or estrogenic effects. High genistein concentrations (>10 μM) also promote proliferation of bone cancer cells in vitro. On the other hand, the most active component of the vitamin D family, calcitriol, has been shown to be tumor protective in vitro and in vivo. The purpose of this study was to examine a putative synergism of genistein and calcitriol in two osteosarcoma cell lines MG-63 (early osteoblast), Saos-2 (mature osteoblast) and primary osteoblasts...

OBJECTIVES: Parkinson's disease (PD) is a progressive neurological disorder associated with motor disabilities and cognitive dysfunction as well. Evidence indicates that PD occurs less frequently in women than men, confirming a role for steroid hormones in protection of dopaminergic nigrostriatal neurons. It is reported that soy genistein, an estrogen agonist phytoestrogen, display neuroprotective effects against neuronal death. In this study we evaluated the effect of genistein in animal models of Parkinsonism (P) and Parkinsonism + ovariectomized (OP)...