Phytoestrogens in postmenopausal indications: A theoretical perspective

A mixture of Pueraria lobata and Platycodon grandiflorum extracts ameliorates RANKL-induced osteoclast differentiation and ovariectomy-induced bone loss by regulating Src- PI3K-AKT and JNK/p38 signaling pathways

Osteoporosis is caused by increased bone resorption due to the excessive activity of osteoclasts. Pueraria lobata has demonstrated the ability to improve bone density in ovariectomized mice, and Platycodon grandiflorum can suppress osteolysis biomarkers such as collagen content in cartilage and alkaline phosphatase activity. In this study, we examined whether HX112, a mixture of Pueraria lobata and Platycodon grandiflorum extracts, could inhibit the receptor activator of nuclear factor-κB (NF-κB) ligand (RANKL)-induced osteoclast differentiation to alleviate osteoporosis. To induce the differentiation of osteoclasts, RAW 264.7 cell were cultured with RANKL and HX112. Osteoclasts differentiation was evaluated by TRAP activity and TRAP staining. Bone resorption as osteoclasts major function was assessed by pit formation assay. As a result, HX112 suppressed osteoclast differentiation and bone resorptive function. Additionally, HX112 reduced the expression of osteoclastogenic genes including NFATc1 and c-Fos, and these effects of HX112 were mediated by inhibiting Src-phosphoinositide 3-kinase (PI3K)- Protein kinase B (Akt) and c-Jun N-terminal kinase (JNK)/p38 signaling pathways. Furthermore, ICR mice were ovariectomized to induce osteoporosis and bone mineral density of femur was measured using micro-CT. Consequently, oral administration of HX112 to ovariectomized mice significantly improved bone microstructure and bone mineral density. Collectively, these findings indicate that the mixed extract of Pueraria lobata and Platycodon grandiflorum may be useful as therapeutics for osteoporosis.

Comparison of the Effect of Fennel and Evening Primrose Oil on Menopausal Problems and Hormonal Levels: A Randomized Controlled Trial

Background

Using natural oral supplements is one of the methods of complementary medicine that has been widely welcomed in the last decade Since studies have reported contradictory results for effectiveness of herbal medicines during menopause and no other more effective herbal medicine has been suggested yet, the researchers of this study decided to compare the fennel and Evening Primrose Oil (EPO) and their effect on menopause problems and sex hormones.

Materials and Methods

The present study was a triple-blinded, controlled clinical trial with 125 participants randomly assigned to. An intervention group received fennel, another intervention group received evening primrose oil, and the placebo group received placebo twice daily for 8 weeks. Pre-intervention and post-intervention results were obtained using hormonal assay and the Menopause Rating Scale (MRS).

Results

In this study, the mean follicle-stimulating hormone (FSH) and estradiol levels changed significantly in the fennel and EPO groups compared to placebo (p < 0.001). The difference in the mean FSH score between the fennel group and EPO group was not significant (p = 0.304), but the difference in the mean estradiol level between these groups was significant (p = 0.043). Moreover, there was a significant difference in the mean MRS score between the intervention groups before the intervention (p < 0.05). However, the difference in the mean MRS score between the fennel and EPO groups was not significant after the intervention (p = 0.322).

Conclusions

Consumption of fennel and EPO can significantly change FSH, estradiol, and psychological menopausal symptoms in postmenopausal women.

Systematic Review of the Impact of Genistein on Diabetes Related Outcomes

Diabetes is the 8th leading cause of death in the world and the prevalence is rising in low-income countries. Cardiovascular diseases are the leading cause of death worldwide, especially for individuals with diabetes. While medications exist to treat symptoms of diabetes, lack of availability and high costs may deter their use by individuals with low incomes as well as those in low-income nations. Therefore, this systematic review was performed to determine whether genistein, a phytoestrogen found in soy products, could provide therapeutic benefits for individuals with diabetes. We searched PubMed and SCOPUS using the terms 'genistein', 'diabetes', and 'glucose' and identified 33 peer-reviewed articles that met our inclusion criteria. In general, preclinical studies demonstrated that genistein decreases body weight and circulating glucose and triglycerides concentrations while increasing insulin levels and insulin sensitivity. Genistein also delayed the onset of type 1 and type 2 diabetes. In contrast, clinical studies utilizing genistein generally reported no significant relationship between genistein and body mass, circulating glucose, A1C concentrations, or onset of type 1 diabetes. However, genistein was found to improve insulin sensitivity and serum triglyceride concentrations and delayed the onset of type 2 diabetes. In summary, preclinical and clinical studies suggest that genistein may help delay the onset of type 2 diabetes and improve several symptoms associated with the disease. Although additional research is required to confirm these findings, the results highlighted in this review provide some evidence that genistein may offer a natural approach to mitigating some of the complications associated with diabetes.

HIV-associated neurotoxicity and cognitive decline: Therapeutic implications

As our understanding of changes to the neurological system has improved, it has become clear that patients who have contracted human immunodeficiency virus type 1 (HIV-1) can potentially suffer from a cascade of neurological issues, including neuropathy, dementia, and declining cognitive function. The progression from mild to severe symptoms tends to affect motor function, followed by cognitive changes. Central nervous system deficits that are observed as the disease progresses have been reported as most severe in later-stage HIV infection. Examining the full spectrum of neuronal damage, generalized cortical atrophy is a common hallmark, resulting in the death of multiple classes of neurons. With antiretroviral therapy (ART), we can partially control disease progression, slowing the onset of the most severe symptoms such as, reducing viral load in the brain, and developing HIV-associated dementia (HAD). HAD is a severe and debilitating outcome from HIV-related neuropathologies. HIV neurotoxicity can be direct (action directly on the neuron) or indirect (actions off-site that affect normal neuronal function). There are two critical HIV-associated proteins, Tat and gp120, which bear responsibility for many of the neuropathologies associated with HAD and HIV-associated neurocognitive disorder (HAND). A cascade of systems is involved in HIV-related neurotoxicity, and determining a critical point where therapeutic strategies can be employed is of the utmost importance. This review will provide an overview of the existing hypotheses on HIV-neurotoxicity and the potential for the development of therapeutics to aid in the treatment of HIV-related nervous system dysfunction.

Novel promising reproductive and metabolic effects of Cicer arietinum L. extract on letrozole induced polycystic ovary syndrome in rat model

ETHNOPHARMACOLOGICAL RELEVANCE

Chickpea was used in both greek and indian traditional medicine for hormonal related conditions as menstrual induction, acceleration of parturation, treatment of retained placenta and stimulation of lactation. Chickpea (Cicer arietinum) sprout isoflavone isolates exhibited reasonable estrogenic activities. Isoflavones, a subtype of phytoestrogens, are plant derivatives with moderate estrogenic activity that tend to have protective effects on hormonal and metabolic abnormalities of women with polycystic ovary syndrome (PCOS).

AIM OF THE STUDY

In this study, we investigated the effect of UPLC/ESI-MS characterized Cicer arietinum L. seeds ethanol extract (CSE) on ovarian hormones, oxidative response and ovarian histological changes on induced PCOS rat model.

MATERIALS AND METHODS

Thirty-five rats were divided into five groups including negative control, PCOS, and treatment groups. PCOS was induced using letrozole (1 mg/kg) daily orally for 21 days. Each treatment group was treated with one of the following for 28 days after induction of PCOS: clomiphene citrate (1 mg/kg), and CSE at 250 and 500 mg/kg. Ovaries and uteri were excised, weighed and their sections were used for quantitative real-time reverse transcriptase polymerase chain reaction, antioxidant assays and histomorphometric study of the ovaries. The antioxidant assays, histopathological examination, hormonal and metabolic profiles, and Cyp11a1(steroidogenic enzyme) mRNA expression were measured.

RESULTS

In all treatment groups, ovarian weight was significantly decreased despite having no significant effect on uterine weight. Histomorphometric study in the treatment groups revealed a significant decrease in the number and diameter of cystic follicles, a significant increase in granulosa cell thickness while, thickness of theca cells was significantly decreased when compared to PCOS. Hormone levels, metabolic profile and antioxidant status were improved in the treatment groups. Moreover, Cyp11a1 mRNA expression was significantly downregulated in the treatment groups compared to PCOS.

CONCLUSIONS

In the current study, CSE enhanced the reproductive and metabolic disorders which were associated with PCOS induction. For the first time, we have highlighted the effect of CSE in treating PCOS and its associated manifestations.

Schisandrol A Exhibits Estrogenic Activity via Estrogen Receptor α-Dependent Signaling Pathway in Estrogen Receptor-Positive Breast Cancer Cells

The aim of this study was to examine the estrogen-like effects of gentiopicroside, macelignan, γ-mangostin, and three lignans (schisandrol A, schisandrol B, and schisandrin C), and their possible mechanism of action. Their effects on the proliferation of the estrogen receptor (ER)-positive breast cancer cell line (MCF-7) were evaluated using Ez-Cytox reagents. The expression of extracellular signal-regulated kinase (ERK), phosphatidylinositol 3-kinase (PI3K), AKT, and estrogen receptor α (ERα) was measured by performing Western blot analysis. 17β-estradiol (E2), also known as estradiol, is an estrogen steroid and was used as a positive control. ICI 182,780 (ICI), an ER antagonist, was used to block the ER function. Our results showed that, except for gentiopicroside, all the compounds promoted proliferation of MCF-7 cells, with schisandrol A being the most effective; this effect was better than that of E2 and was mitigated by ICI. Consistently, the expression of ERK, PI3K, AKT, and ERα increased following treatment with schisandrol A; this effect was slightly better than that of E2 and was mitigated by ICI. Taken together, the ERα induction via the PI3K/AKT and ERK signaling pathways may be a potential mechanism underlying the estrogen-like effects of schisandrol A. This study provides an experimental basis for the application of schisandrol A as a phytoestrogen for the prevention of menopausal symptoms.

Therapeutic effects of traditional Thai herbal blood and wind tonic formulations for treatment of menopausal symptoms

INTRODUCTION

Traditional Thai herbal medicine formulations have been used as alternative therapies for menopausal symptoms due to concerns from adverse effects associated with hormone therapy. This study aimed to demonstrate the effects of traditional Thai herbal blood and wind tonic formulations used by a traditional Thai medicine doctor, Mr. Somporn Chanwanitsakul, in postmenopausal women.

MATERIALS AND METHODS

A pilot clinical study was conducted on thirty-five postmenopausal women, referring to Tambon Thung Tam Sao Health Promotion Hospital, Hat Yai, Songkhla, from October 2019 to March 2020. The participants consumed combined Thai herbal formulations including blood tonic and wind tonic thrice daily for four weeks. Outcomes were assessed at baseline, end of treatment (4 weeks), and follow-up (8 weeks). Pre- and post-treatment measures included menopause rating scale, sleep quality, and quality of life questionnaire. All data were analyzed using SPSS software at the significance level of 0.05.

RESULTS

Therapeutic effects of Thai herbal medicine formulations on menopausal symptoms intensity were assessed by modified Menopause Rating Scale (MRS). Severity of women's total menopausal symptoms decreased significantly (p < 0.05) at end of treatment and follow-up. Analysis of changes in specific symptoms indicated significantly less moderate headache, mild hot flashes, sweating, emotional instability, irritability, anxiety, sleep problem, lethargy, back pain, joint pain, muscular discomfort, dry skin, dryness of vagina, boring sex, and frequent urination (MRS score 0). In addition, subjective analysis of sleep quality using Pittsburgh Sleep Quality Index (PSQI) data revealed significant post-treatment improvements in subjective sleep quality and daytime dysfunction over the last month (PSQI score 0). Furthermore, subjective analysis of quality of life using World Health Organization Quality of Life Brief showed significant post-treatment improvement in psychological health (score 23).

CONCLUSION

The findings demonstrate that Thai herbal medicine formulations used by a traditional Thai medicine doctor, Mr. Somporn Chanwanitsakul, are effective for treating menopausal symptoms and improve sleep quality and quality of life in postmenopausal women.

[Effects of the use of 17 β-estradiol and genistein in Alzheimer's disease in women with menopause]

The use of 17 β-estradiol and genistein in women with menopause helps in the reduction of vasomotor symptoms and cognitive improvement. There is evidence on the use of certain flavonoids such as genistein, which has a potentially neuroprotective role in neurodegenerative diseases such as Alzheimer's. Scientific evidence on the effects of phytoestrogens and genistein during menopause and their effect on cognition are scarce, however, in the present review it was found that the intervention with 17 β-estradiol has positive effects on cognition in women with Alzheimer's disease. In addition, the use of genistein, daidzein or any supplement based on isoflavones may influence vasomotor symptoms. 17 β-estradiol supplements in women in early menopause and with some degree of cognitive impairment may have beneficial effects.

The Aqueous Extract of Dacryodes edulis (Burseraceae) Leaves Inhibits Cell Proliferation Induced by Estradiol on the Uterus and Vagina of Ovariectomized Female Wistar Rats

Proliferation is a cellular process strongly linked to the genesis of cancer. Natural substances with antiproliferative activities are currently potential alternatives in the treatment of cancers. Dacryodes edulis, for instance, is a medicinal plant traditionally used in the treatment of cancer. Scientific studies have reported the antioxidant activity of this plant. In addition, the presence of prostate cancer chemopreventive polyphenols was reported in D. edulis extracts. Therefore, this study was aimed to evaluate the effects of the aqueous extract of D. edulis leaves on cell proliferation induced by estradiol in ovariectomized female Wistar rats. In this regard, ovariectomized (OVX) rats were cotreated with estradiol valerate (E₂V) (0.75 mg/kg) and the aqueous extract of D. edulis leaves. Control groups received either the vehicle (sham-operated animals and the OVX control), E₂V (0.75 mg/kg) only, or E₂V (0.75 mg/kg) and tamoxifen (10 mg/kg). Treatments were administered orally for 3 consecutive days, and animals were sacrificed thereafter. Epithelial heights of the uterus and vagina were assessed. Uterine levels of total cholesterol and estradiol were determined as well. Results showed that the aqueous extract of D. edulis leaves reversed the effects of estradiol as it reduced uterine weight (p < 0.05), uterine (p < 0.05), and vaginal (p < 0.001) epithelium heights. This antiproliferative effect of D. edulis was associated with reduced tissue (uterine) levels of estradiol (p < 0.001). These results suggest that the aqueous extract of D. edulis leaves could be a potential alternative treatment for proliferation-related diseases.

Genistein Improves Bone Healing via Triggering Estrogen Receptor Alpha-Mediated Expressions of Osteogenesis-Associated Genes and Consequent Maturation of Osteoblasts

Osteoporosis-associated fractures may cause higher morbidity and mortality. Our previous study showed the effects of genistein, a phytoestrogen, on the induction of estrogen receptor alpha (ERα) gene expression and stimulation of osteoblast mineralization. In this study, rat calvarial osteoblasts and an animal bone defect model were used to investigate the effects of genistein on bone healing. Treatment with genistein caused a time-dependent increase in alkaline phosphatase (ALP) activity in rat osteoblasts. Levels of cytosolic and nuclear ERα significantly augmented following exposure to genistein. Subsequently, genistein elevated levels of ALP mRNA and protein in rat osteoblasts. Moreover, genistein induced other osteogenesis-associated osteocalcin and Runx2 mRNA and protein expressions. Knocking-down ERα using RNA interference concurrently inhibited genistein-induced Runx2, osteocalcin, and ALP mRNA expression. Attractively, administration of ICR mice suffering bone defects with genistein caused significant increases in the callus width, chondrocyte proliferation, and ALP synthesis. Results of microcomputed tomography revealed that administration of genistein increased trabecular bone numbers and improved the bone thickness and volume. This study showed that genistein can improve bone healing via triggering ERα-mediated osteogenesis-associated gene expressions and subsequent osteoblast maturation.

Bone-protective and anti-tumor effect of baicalin in osteotropic breast cancer via induction of apoptosis

PURPOSE

Research suggested that bone is the specific target organ for breast cancer metastasis. The related tumor causes significant morbidity due to a reduction in quality of life and physical function. Increased osteoclast function is implicated in the bone microenvironment during the outgrowth of breast cancer. In the present experimental study, we examined the potential bone-protective effect of baicalin osteotropic breast Cancer and explored the possible mechanism of action.

METHODS

In vitro cell viability effect of baicalin was assessed on the breast cancer cell lines (MDA-MB-231 and MCF-7). We also estimated the in vitro osteoclast and bone resorption. Further, baicalin-regulated osteoblastogenesis and osteoclastogenesis were also estimated in vitro. Finally, the role of the baicalin in the expansion of osteolytic bone disease was scrutinized in a breast cancer bone metastases model.

RESULTS

Baicalin significantly (p < 0.001) downregulated the viability of murine and human cancer cell lines and diminished the osteoclastogenesis of osteoclast progenitors via estimation with the help of qRT-PCR. Baicalin showed the downregulation in the mRNA expression of OCN and ALP. Baicalin reduced the TRAP-positive cells in the presence of RANKL. Baicalin considerably upregulated the cytochrome c secretion into the cytoplasm. Baicalin markedly increased the DNA fragmentation, caspase-3, caspase-8, and caspase-9. Baicalin significantly (p < 0.001) reduced the metastatic growth of MDA-MB-231 cells,preserving the bone mass in a bone metastasis model.

CONCLUSION

Collectively, we can conclude that these results highlight the bone-protective effect of baicalin, which also highlighted the anti-tumor effect; further research is needed into the likely effects on bone health in the bone metastases and osteoporosis populations, such as post-menopausal women with breast cancer.

A chitosan film containing quercetin-loaded transfersomes for treatment of secondary osteoporosis

Osteoporosis, due to its prevalence worldwide, is a serious health problem. Topical administration of quercetin, a phytoestrogen, in the form of deformable transfersomes, could be used to treat osteoporosis to overcome its low oral solubility and bioavailability. Formulation process of transfersomes was screened by fractional factorial design and further optimized using full factorial design. Transfersomes showed good characteristics such as entrapment efficiency, particle size, zeta potential, and polydispersity index (83.0 ± 2.2%, 75.95 ± 2 nm, - 13.6 ± 6 mv and 0.333, respectively). Transfersomes were further loaded into chitosan film and showed good permeation through rat skin. Further, glucocorticoid-induced osteoporosis rat model showed induction of osteoporosis after day 30. On day 45, treatment with chitosan film containing quercetin-loaded transfersomes showed remarkable rise in femur thickness, length, density as well as in serum biochemical parameters such as calcium, phosphorous, alkaline phosphatase, and tartrate-resistant alkaline phosphatase compared to positive control group. Tensile strength of osteoporotic femur bone was also found to be increased and was comparable with normal group. Histomicrographic analysis of femur bone exhibited less disruptive and lytic changes. Thus, all the above findings indicated the beneficial effects of quercetin-loaded transfersome chitosan film, due to decline in osteoclastogenesis and osteoblast apoptosis, which further favored increase in osteoblast numbers and mineralization of bones. Thus, chitosan film containing quercetin-loaded transfersomes was found to be good alternative to oral administration of quercetin to treat osteoporosis, while easy applicability of film in the form of wrist band anytime, anywhere, and even at work achieve patient compliance. Graphical abstract.

Effects of Isolated Isoflavones Intake on Health

BACKGROUND

Isoflavones are naturally occurring flavonoids, commonly found in the food consumed for centuries in the East-Asian population, characterized by a structure able to exert nonsteroidal estrogen-like activity on human cells. They have attracted researcher interest all around the word, following the results obtained in epidemiological and clinical studies. The involvement of isoflavones and their metabolites in various biological processes suggests that they can influence several metabolic pathways and can influence the gene expression at epigenetic level, involving effects that probably are due to early life exposure. They show positive health effects on several diseases, especially in the prevention of coronary heart and neurological diseases, hormone-related cancers, osteoporosis, and postmenopausal symptoms.

METHODS

We have performed a critical evaluation of available literature trough a structured search of bibliographic databases about isoflavones health promoting properties, risk assessment and mechanisms of action. In addition, we supplied useful information on their biochemical properties, sources and bioavailability.

RESULTS

Although these molecules have been the subjects of numerous researches, their role for the wellness of the human organism remains controversial. Moreover, there are substantial inconsistencies between the results obtained by epidemiologic studies conducted on Eastern population, which found high health promoting properties, and Western clinical trials, which found much less positive effects.

CONCLUSION

Further epidemiologic studies and well-designed prospective human studies are to determine the beneficial effects of isoflavones exposure, as well as establishing its safe therapeutic.

A study of zearalenone biosorption and metabolisation by prokaryotic and eukaryotic cells

A study of the mechanism responsible for the zearalenone (ZEA) neutralization by lactic acid bacteria Lactococcus lactis 56 and L929 cell line was carried out by determination of the kinetics of the binding process. In the case of prokaryotic cells the biosorption process was non-linear and three steps were identified. The maximum efficiency of zearalenone binding to L. lactis was almost 30% and no metabolites were observed. In turn, for eukaryotic cells only two steps of the binding process were differentiated, and the efficiency of zearalenone binding was 53.99%. Furthermore, L929 cell line metabolizes zearalenone to α-ZOL and β-ZOL. Additionally, Fourier transform infrared spectroscopy (FTIR) was used for description of the structural changes at the protein and lipid level, while Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF-MS) was applied to detect changes at the molecular level.

Effects of endophyte-infected tall fescue seed and red clover isoflavones on rumen microbial populations and physiological parameters of beef cattle

Lolium arundinaceum [(Darbyshire) tall fescue] toxicosis is responsible for substantial beef production losses in the United States, due to its negative effects on reproduction, growth, and feed efficiency. These effects are consequences of toxic alkaloids within tall fescue. Interseeding legumes, such as Trifolium pratense (red clover), into pastures has been shown to mitigate a portion of these effects. Clovers contain isoflavones, which may play a role in tall fescue toxicosis mitigation. The present study utilized 36 Angus steers to determine the effects of daily supplementation with a red clover-isolated isoflavone feed additive on physiological symptoms of tall fescue toxicosis and the rumen microbial environment over a 21-d period. Angus steers were initially stratified based upon their single nucleotide polymorphism genotype at the DRD2 receptor. Treatments were then randomly assigned in a 2 × 2 factorial arrangement within a completely randomized design, where treatment factors consisted of tall fescue seed type (endophyte-infected tall fescue seed vs. endophyte-free tall fescue seed) supplemented with and without the isoflavone additive. Steers that consumed endophyte-infected tall fescue seed had lower serum prolactin concentrations (P = 0.0007), average daily gain (ADG; P = 0.003), final body weight (BW; P = 0.004), and feed efficiency (P = 0.018) when compared with steers that consumed endophyte-free tall fescue seed. Serum insulin-like growth factor-1 (IGF-1) tended to be reduced with supplementation of isoflavones (P = 0.06) but was unaffected by seed type (P ≥ 0.10) and seed by treatment interaction (P ≥ 0.10). Isoflavones reduced serum glucose levels (P = 0.023), but neither seed type, isoflavones, or their interaction affected serum urea nitrogen (SUN), nonesterified fatty acids (NEFA), or insulin (P ≥ 0.10). Volatile fatty acid concentrations, dry matter intake (DMI), ruminal pH, and overall feeding behaviors were also unaffected by seed type or isoflavone treatments (P ≥ 0.10). Twenty-eight ruminal bacteria taxa shifted as a result of seed type or isoflavone treatment (P < 0.05). In this experiment, feeding isoflavones to Angus cattle did not completely mitigate all symptoms of fescue toxicosis. However, dose–response trials may aid future research to determine if dietary supplementation with isoflavones alleviates fescue toxicosis symptoms and promotes livestock growth and performance.

Sesquiterpenes from Cyperus rotundus and 4α,5α-oxidoeudesm-11-en-3-one as a potential selective estrogen receptor modulator

Estrogenic activity-oriented fractionation and purification of methanol extract from the rhizome of Cyperus rotundus, a well-known traditional herbal medicine, led to the isolation of six sesquiterpenes. 4α,5α-Oxidoeudesm-11-en-3-one (2) and cyper-11-ene-3,4-dione (3) together with four known sesquiterpenes, cyperotundone (1), caryophyllene α-oxide (4), α-cyperone (5), and isocyperol (6) were obtained from the hexane and dichloromethane fractions. Compounds 2 and 3 were newly isolated from natural resources in particular. To identify the possible use of isolated compounds as an alternative to hormone replacement therapy (HRT), estrogenic activity was evaluated by E-screen assay on MCF-7 BUS cells. Among the all isolated compounds from the rhizome of Cyperus rotundus, newly isolated from natural resource, 2 exhibited the most potent estrogenic activity. In an estrogen sensitive reporter gene assay, 2 significantly increased transcriptional activities. As a phytoestrogen, 2 was assessed by investigating dual action on ER-α and ER-β in competitive binding assay. It was found that 2 exerted higher binding affinity to ER-β than ER-α and it also showed both estrogenic and antiestrogenic effects depending on the E₂ concentration. Our results indicate that newly isolated from Cyperus rotundus, 2 has biphasic activities on estrogen receptors which could be useful as an alternative HRT.

A decade of nutraceutical patents: where are we now in 2018?

INTRODUCTION

In the last 10 years, nutraceuticals have grown in interest to researchers, industry, and consumers and are now familiar in the collective imagination as a tool for preventing the onset of a disease. Often nutraceuticals are confused with biologically active phytochemicals/botanicals which can have health benefits. This is a misunderstanding however as the term nutraceutical refers to a product that must have a beneficial effect on health proven by clinical testing. Areas covered: A search has been performed on both recent patents and the literature regarding nutraceuticals focusing on the beneficial and proven health effects on pathological conditions to give an overview of the state-of-the-art developments in this area. Patents and literature data addressing specific pathological conditions are discussed. Expert opinion: Nutraceuticals represent a challenge for the future of drug-based pharmacotherapy, and, at the same time, are a powerful tool for the prevention of chronic disease. They are not proposed as an alternative to drugs, but instead, can be helpful to complement a pharmacological therapy and prevent the onset of chronic diseases in subjects who do not qualify for conventional pharmacological treatment.

Biotransformation of soy flour isoflavones by Aspergillus niger NRRL 3122 β-glucosidase enzyme

β-glucosidase enzyme produced from Aspergillus niger NRRL 3122 has been partially purified and characterised. Its molecular weight was 180 KDa. The optimal pH and temperature were 3.98 and 55 °C, respectively. It promoted the hydrolysis of soy flour isoflavone glycosides to their aglycone. Two-level Plackett-Burman design was applied and effective variables for genistein production were determined. Reaction time had a significant positive effect, and pH had a significant negative effect. They were further evaluated using Box-Behnken model. Accordingly, the optimal combination of the major reaction affecting factors was reaction time, 5 h and pH, 4. The concentration of genistein increased by 11.73 folds using this optimal combination. The antioxidant activity of the non-biotransformed and biotransformed soy flour extracts was determined by DPPH method. It was found that biotransformation increased the antioxidant activity by four folds.

Effects of the Hormone Replacement Therapy and of Soy Isoflavones on Bone Resorption in Postmenopause

Postmenopausal osteoporosis is the most common form of osteoporosis and one of the major public health problems in developed countries. The prevalence of this condition, associated with the physiological stage of menopause, is continuously increasing. This study evaluated the effectiveness of soy isoflavones as compared to hormone replacement therapy (HRT) in low doses, on the prevention of postmenopausal osteoporosis, by determining bone mineral density (BMD) and urinary deoxypyridinoline (D-pyr) in physiological postmenopausal women. The study was conducted over a period of 12 months, on three parallel groups, which included a total of 325 postmenopausal women (HRT group: n = 95; phytoestrogens group: n = 124; control group: n = 106). At the one-year evaluation, we observed T-score normalization in a small number of cases (5.26%, 2.42% and 0.00%, respectively). The average values of D-Pyr decreased by 11.38% in the group treated with phytoestrogens (p < 0.05) and by 15.32% in the group that followed HRT (p < 0.05); it increased by 4.38% in the control group (p > 0.05). Both therapies have beneficial effects on bone metabolism, leading to a significant decrease in the evolution of bone resorption and there are no major differences between the efficacy of HRT and phytoestrogens in terms of the effects on BMD and bone resorption.

Effect of endocrine disruptors on the ratio of X and Y chromosome-bearing live spermatozoa

Although equal numbers of X and Y spermatozoa are produced during spermatogenesis, the sex chromosome ratio in ejaculated spermatozoa can be altered by exposure to endocrine-disrupting chemicals (EDCs), which can be reflected by altered sex ratios at birth. Here, we hypothesized EDCs affect sperm functions and viability of X and Y chromosome-bearing human spermatozoa. After exposure to genistein (Gen), bisphenol A (BPA), 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), dibromochloropropane (DBCP), and diazinon (Diaz), we evaluated motility, viability, capacitation, and differential viability of X and Y spermatozoa. All EDCs tested altered sperm viability, motility, and capacitation. Interestingly, the Y/X ratio of live spermatozoa was significantly lower in sperm treated with TCDD, DBCP, and Diaz than control spermatozoa. Our results suggest that some of EDCs have larger effects on the viability of Y spermatozoa than X spermatozoa, implicating that a reduction in Y sperm viability may result in a female-biased sex ratio of offspring at birth.

Dehydrodiconiferyl Alcohol Inhibits Osteoclast Differentiation and Ovariectomy-Induced Bone Loss through Acting as an Estrogen Receptor Agonist

Estrogen deficiency after menopause increases bone loss by activating RANKL-induced osteoclast differentiation. Dehydrodiconiferyl alcohol (DHCA), a lignan originally isolated from Cucurbita moschata, has been thought to be a phytoestrogen based on its structure. In this study, we tested whether DHCA could affect RANKL-induced osteoclastogenesis in vitro and ovariectomy-induced bone loss in vivo. In RAW264.7 cells, DHCA inhibited RANKL-induced differentiation of osteoclasts. Consistently, expression of the six osteoclastogenic genes induced by RANKL was down-regulated. DHCA was also shown to suppress the NF-κB and p38 MAPK signaling pathways by activating AMPK. Data from transient transfection assays suggested that DHCA might activate the estrogen receptor signaling pathway. Effects of DHCA on RANKL-induced osteoclastogenesis were reduced when cells were treated with specific siRNA to ERα, but not to ERβ. Interestingly, DHCA was predicted from molecular docking simulation to bind to both ERα and ERβ. Indeed, data from an estrogen receptor competition assay revealed that DHCA acted as an agonist on both estrogen receptors. In the ovariectomized (Ovx) mouse model, DHCA prevented Ovx-induced bone loss by inhibiting osteoclastogenesis. Taken together, our results suggest that DHCA may be developed as an efficient therapeutic for osteoporosis by regulating osteoclastogenesis through its estrogenic effects.

Response Surface Methodology for Optimization of Genistein Content in Soy Flour and its Effect on the Antioxidant Activity

Biotransformation of isoflavones glycosides into the aglycone form is essential to attain the maximum bioavailability. The factors affecting deglycosylation of genistin in soy flour using commercial β-glucosidase enzyme were evaluated. The presence of genistin in soy flour was confirmed by isolation through chromatographic fractionation and identification by spectral method. Two-levels Plackett-Burman design was applied and effective variables for genistein production were determined. Agitation rate, enzyme concentration, and reaction time, owing to their significant positive effect, and pH, owing to its significant negative effect, were further evaluated using Box-Behnken model. Accordingly the optimal combination of the major reaction affecting factors was "enzyme concentration, 1 IU; agitation speed, 250 rpm; reaction time, 5 h and pH 4. The concentration of genistein can be increased by 9.91 folds (from 0.8 mg/g in the non biotransformed soy flour to 7.93 mg/g in the biotransformed one) using the determined optimal combination of major reaction affecting factors. The antioxidant activity of the non biotransformed and biotransformed soy flour extracts was determined by DPPH method. It was found that biotransformation increase the antioxidant activity by two folds. The concentration causing a 50% reduction of DPPH absorbance (EC₅₀) were 10 and 5 mg/mL for the non biotransformed and biotransformed soy flour extracts, respectively.

Effects of three different formulae of Gamisoyosan on lipid accumulation induced by oleic acid in HepG2 cells

BACKGROUND

Gamisoyosan (GSS) is an herbal formula which has been used to treat women's diseases for several hundred years in Korea. GSS is one of the three most common prescriptions among women and is used to treat menopausal symptoms. Fatty liver disease is also common in postmenopausal women and can precede more severe diseases, such as steatohepatitis. The present study compared the effects of GSS on fatty liver using three different formulae, Dongui-Bogam (KIOM A), Korean Pharmacopeia (KIOM B) and Korean National Health Insurance (KIOM C).

METHODS

In oleic acid-induced HepG2 fatty liver cells, cellular lipid accumulation, triglycerides and total cholesterol were measured after treatment with three GSS formulae and simvastatin as a positive control. To investigate the phytoestrogen activity of GSS, MCF-7 cells were treated with GSS, and hormone levels were quantified. Also, qualitative analysis was performed with UPLC.

RESULTS

All types of GSS decreased cellular lipid accumulation. KIOM A was slightly less effective than the other two GSS formulae. KIOM B and KIOM C decreased cellular triglycerides more effective than simvastatin, but KIOM A did not affect cellular triglycerides. Cellular total cholesterol was decreased by all GSS and simvastatin. GSS showed phytoestrogen activity in MCF-7 cells. From the UPLC analysis data, geniposide, paeoniflorin and glycyrrhizin were detected form three GSS formulae.

CONCLUSION

These results suggest that all GSS formulae have a beneficial effect on fatty liver disease during menopause and that differences of formula have no effect on the efficacy of the prescription.

Equol, a Dietary Daidzein Gut Metabolite Attenuates Microglial Activation and Potentiates Neuroprotection In Vitro

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. Effects of Equol on the expression of inducible nitric oxide synthase (iNOS), cyclooxygenase (COX-2), Mitogen activated protein kinase (MAPK) signaling proteins, and apoptosis-related proteins were measured by western blot analysis. Equol inhibited the lipopolysaccharide (LPS)-induced TLR4 activation, MAPK activation, NF-kB-mediated transcription of inflammatory mediators, production of nitric oxide (NO), release of prostaglandin E2 (PGE-2), secretion of tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6), in Lipopolysaccharide (LPS)-activated murine microglia cells. Additionally, Equol protects neurons from neuroinflammatory injury mediated by LPS-activated microglia through downregulation of neuronal apoptosis, increased neurite outgrowth in N2a cell and neurotrophins like nerve growth factor (NGF) production through astrocytes further supporting its neuroprotective potential. These findings provide novel insight into the anti-neuroinflammatory effects of Equol on microglial cells, which may have clinical significance in cases of neurodegeneration.

Puerarin suppression of Aβ1-42-induced primary cortical neuron death is largely dependent on ERβ

Recent study has suggested that estrogen replacement therapy (ERT) can decrease the risk of the development of Alzheimer's disease (AD), and phytoestrogen has been proposed as a potential alternative to ERT. In this study, we investigated the protective function of puerarin (a phytoestrogen isolated from puerarin lobate) against amyloid beta (Aβ_1-42)-induced toxicity in cortical neurons and established the connection between such a protection and estrogen receptor (ER) activation. Puerarin suppressed Aβ_1-42-induced cortical neuron death in a concentration-dependent manner. Morphological examination showed that puerarin not only suppressed Aβ_1-42-induced decrease in neuron numbers, but also promoted neurite growth. In addition, we found that the neuroprotection of puerarin was dependent on the activation of estrogen receptors (ERs), as demonstrated by activation of ERE-reporter gene. Puerarin preferentially up-regulated the expression of ERβ but not ERα, and ERβ-specific siRNA significantly reduced the neuroprotection of puerarin. Taken together, our results indicated that puerarin is neuroprotective against Aβ_1-42 toxicity via the activation of estrogen receptors, and ERβ plays a key role in the process. Our novel findings provide a potential strategy for the prevention of neurodegeneration and the treatment of AD.

Protective effects of hydroponic Teucrium polium on hippocampal neurodegeneration in ovariectomized rats

BACKGROUND

The hippocampus is a target of ovarian hormones, and is necessary for memory. Ovarian hormone loss is associated with a progressive reduction in synaptic strength and dendritic spine. Teucrium polium has beneficial effects on learning and memory. However, it remains unknown whether Teucrium polium ameliorates hippocampal cells spike activity and morphological impairments induced by estrogen deficiency.

METHODS

In the present study, we investigated the effects of hydroponic Teucrium polium on hippocampal neuronal activity and morpho-histochemistry of bilateral ovariectomized (OVX) rats. Tetanic potentiation or depression with posttetanic potentiation and depression was recorded extracellularly in response to ipsilateral entorhinal cortex high frequency stimulation. In morpho-histochemical study revealing of the activity of Ca2+-dependent acid phosphatase was observed. In all groups (sham-operated, sham + Teucrium polium, OVX, OVX + Teucrium polium), most recorded hippocampal neurons at HFS of entorhinal cortex showed TD-PTP responses.

RESULTS

After 8 weeks in OVX group an anomalous evoked spike activity was detected (a high percentage of typical areactive units). In OVX + Teucrium polium group a synaptic activity was revealed, indicating prevention OVX-induced degenerative alterations: balance of types of responses was close to norm and areactive units were not recorded. All recorded neurons in sham + Teucrium polium group were characterized by the highest mean frequency background and poststimulus activity. In OVX+ Teucrium polium group the hippocampal cells had recovered their size and shape in CA1 and CA3 field compared with OVX group where hippocampal cells were characterized by a sharp drop in phosphatase activity and there was a complete lack of processes reaction.

CONCLUSION

Thus, Teucrium polium reduced OVX-induce neurodegenerative alterations in entorhinal cortex-hippocamp circuitry and facilitated neuronal survival by modulating activity of neurotransmitters and network plasticity.

Estrogenic Receptor-Functionalized Magnetite Nanoparticles for Rapid Separation of Phytoestrogens in Plant Extracts

With growing interests of phytoestrogens, many natural phytochemicals extracted from diverse plant species have been explored for their estrogenic-like activities and potential applications. In this work, a simple and rapid separation of phytoestrogenic compounds from crude plant extracts was purposed using magnetic nanoparticles (MNPs) of Fe₃O₄ immobilized with the ligand-binding domain (LBD) of estrogen receptor alpha (ERα). The recombinant LBD-ERα peptide of 40 kDa was produced and subsequently covalently linked to MNPs. One milligram of the LBD-ERα-immobilized MNPs demonstrated a specific binding to the standard 17β-estradiol (E2) of 3.37 nmol and 91.3-100 % of the bound E2 were subsequently recovered. LBD-ERα-immobilized MNPs could separate phytoestrogens of 4.6 nmol E2-equivalent activity from a 1-mg crude extract of Asparagus racemosus. The produced MNPs showed no separation yield when were applied to the negative controls, the crude extract of radish (Raphanus sativus), and the standard progesterone (P4). Thin-layer chromatography demonstrated a single phytochemical band of the separated phytoestrogens, which exhibited the activity to promote MCF-7 cell proliferation at 4.7 folds greater than the crude A. racemosus extract. The results of this work demonstrated a simple method to specifically separate phytoestrogens from crude plant extracts via the LBD-ERα-immobilized MNPs.

Antihyperlipidemic activity of chickpea sprouts supplementation in ovariectomy-induced dyslipidemia in rats

Background:

Phytoestrogens are increasingly becoming popular as alternatives for hormone replacement therapy in postmenopausal condition.

Objective:

In this study, the antihyperlipidemic effect of chickpea (Cicer arientum) sprouts was evaluated in ovariectomy-induced dyslipidemia in rat model in comparison with standard antihyperlipidemic agent atorvastatin.

Materials and Methods:

A total of 24 female adult Wistar rats were divided into four groups that is, Group I - Control; Group II - Ovariectomized (OVX) rats; Group III - OVX + germinated chickpea sprouts (20% in diet) and Group IV OVX + atorvastatin (1.2 mg/kg b.wt, p.o.). Body and organ weights, serum, and liver lipid profile were assessed at the end of 8 weeks.

Results:

The results indicated that ovariectomy significantly (P < 0.05) increased total cholesterol, nonhigh-density lipoprotein cholesterol and triglycerides (TGs) in serum and liver. The total lipid and phospholipid content in liver were also significantly (P < 0.05) increased. The weights of uterus and heart were significantly (P < 0.05) decreased. Dietary supplementation with germinated chickpea normalized the lipid profile in serum and liver. Further, high-density lipoprotein (HDL) cholesterol, body weight, uterine, heart, and spleen weights were significantly (P < 0.05) increased. Atorvastatin administration showed similarly normalized lipid profile, but showed no improvement on decreased uterus and heart weights. Histopathological examination revealed fatty changes in liver, uterine atrophy, and subintimal fat accumulation in aorta in OVX group. The changes were mild in chickpea group with no improvement in statin group.

Conclusions:

Germinated seeds of chickpea showed significant antihyperlipidemic activity, which was comparable to atorvastatin. Further, germinated chickpea improved organ weights and helped in the reversal of histopathological changes suggesting its usefulness in postmenopausal condition.

Puerarin induces the upregulation of glutathione levels and nuclear translocation of Nrf2 through PI3K/Akt/GSK-3β signaling events in PC12 cells exposed to lead

Oxidative stress is thought to be involved in lead-induced toxicity, especially affecting the brain. We reported previously that puerarin possesses antioxidative properties in the nervous system. Therefore, the aim of the present study was to test the hypothesis that puerarin inhibits lead acetate-induced oxidative stress in PC12 cells by interrupting phosphatidylinositol-3 kinase (PI3K)/Akt signaling through increasing glutathione (GSH) synthesis. Our results showed that puerarin attenuates oxidative stress in a concentration-dependent manner in PC12 cells exposed to lead acetate demonstrated by scavenging reactive oxygen species (ROS) and reducing lipid peroxidation (LPO). Treatment with puerarin significantly up-regulates glutamate cysteine ligase catalytic subunit (GCLc) expression both at its mRNA and protein levels, but not glutamate cysteine ligase modifier (GCLm) subunit, accompanying the elevation of cellular glutathione level. The increased nuclear accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) was not because of increased transcription of Nrf2 as Nrf2 transcript levels did not change after puerarin treatment. The effects of puerarin could be partially blocked by pharmacologic inhibition of PI3K and the glycogen synthase kinase 3β (GSK-3β) pathways with LY294002 and LiCl, respectively. On the other hand, puerarin treatment promoted Akt and GSK-3β phosphorylation in PC12 cells exposed to lead acetate. Moreover, puerarin failed to modulate the phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2), p-c-Jun N-terminal kinases (JNK), and p-p38 mitogen-activated protein kinase (MAPK) demonstrating some specificity for its action on the PI3K/GSK-3β pathway. These findings suggest that puerarin as a phytoestrogen might be an attractive agent for prevention and treatment of chronic diseases related to lead neurotoxicity.

Phloretin promotes osteoclast apoptosis in murine macrophages and inhibits estrogen deficiency-induced osteoporosis in mice

Bone-remodeling imbalance induced by increased osteoclast formation and bone resorption is known to cause skeletal diseases such as osteoporosis. The reduction of estrogen levels at menopause is one of the strongest risk factors developing postmenopausal osteoporosis. This study investigated osteoprotective effects of the dihydrochalcone phloretin found in apple tree leaves on bone loss in ovariectomized (OVX) C57BL/6 female mice as a model for postmenopausal osteoporosis. OVX demoted bone mineral density (BMD) of mouse femurs, reduced serum 17β-estradiol level and enhanced serum receptor activator of NF-κB ligand (RANKL)/osteoprotegerin ratio with uterine atrophy. Oral administration of 10 mg/kg phloretin to OVX mice for 8 weeks improved such effects, compared to sham-operated mice. Phloretin attenuated TRAP activity and cellular expression of β3 integrin and carbonic anhydrase II augmented in femoral bone tissues of OVX mice. This study further examined that osteogenic activity of phloretin in RANKL-differentiated Raw 264.7 macrophages into mature osteoclasts. Phloretin at 1-20 μM stimulated Smac expression and capase-3 activation concurrently with nuclear fragmentation of multi-nucleated osteoclasts, indicating that this compound promoted osteoclast apoptosis. Consistently, phloretin enhanced bcl-2 induction but diminished bax expression. Furthermore, phloretin activated ASK-1-diverged JNK and p38 MAPK signaling pathways in mature osteoclasts, whereas it dose-dependently inhibited the RANKL-stimulated activation of ERK. Therefore, phloretin manipulated ASK-1-MAPK signal transduction leading to transcription of apoptotic genes. Phloretin was effective in preventing estrogen deficiency-induced osteoclastogenic resorption.

Evaluation of estrogenic, antiestrogenic and genotoxic activity of nemorosone, the major compound found in brown Cuban propolis

BACKGROUND

Brown propolis is the major type of propolis found in Cuba; its principal component is nemorosone, the major constituent of Clusia rosea floral resins. Nemorosone has received increasing attention due to its strong in vitro anti-cancer action. The citotoxicity of nemorosone in several human cancer cell lines has been reported and correlated to the direct action it has on the estrogen receptor (ER). Breast cancer can be treated with agents that target estrogen-mediated signaling, such as antiestrogens. Phytoestrogen can mimic or modulate the actions of endogenous estrogens and the treatment of breast cancer with phytoestrogens may be a valid strategy, since they have shown anti-cancer activity.

METHODS

The aim of the present investigation was to assess the capacity of nemorosone to interact with ERs, by Recombinant Yeast Assay (RYA) and E-screen assays, and to determine by comet assay, if the compound causes DNA-damaging in tumoral and non-tumoral breast cells.

RESULTS

Nemorosone did not present estrogenic activity, however, it inhibited the 17-β-estradiol (E2) action when either of both methods was used, showing their antiestrogenicity. The DNA damage induced by the benzophenone in cancer and normal breast cells presented negative results.

CONCLUSION

These findings suggest that nemorosone may have therapeutic application in the treatment of breast cancer.

Estrogen receptor is activated by korean red ginseng in vitro but not in vivo

Ginseng has been used as a traditional medicine for treatment of many diseases and for general health maintenance in people of all ages. Ginseng is also used to ameliorate menopausal systems. We investigated the estrogenic activity of Korean red ginseng (KRG) in a transient transfection system, using estrogen receptor (ER) and estrogen-responsive luciferase plasmids in MCF-7 cells. The extract activated both ERα and ERβ. KRG modulated the mRNA levels of estrogen-responsive genes such as pS2 and ESR1 and decreased the protein level of ERα. In order to examine in vivo estrogenic activity of KRG, sixteen female Sprague-Dawley rats separated into four groups were studied for nine weeks: non-ovariectomized (OVX) rats treated with olive oil, OVX rats treated with olive oil, OVX rats treated with 17-β-estradiol (E2) in olive oil, and OVX rats treated with KRG extract in olive oil. The experiments were repeated for three times and the data of twelve rats were combined. Body weight of OVX rats was greater than that of sham-operated control rats and was decreased by E2 treatment. Uterine weight increased after E2 treatment compared to OVX rats. However, no difference in body or uterine weight was observed with KRG intake. KRG induced reductions in total cholesterol, low density lipoprotein cholesterol/total cholesterol, high density lipoprotein cholesterol/total cholesterol, and low density lipoprotein cholesterol/high density lipoprotein cholesterol, but not to the same degree as did E2 intake. These results show that KRG does contain estrogenic activity as manifested by in vitro study but the activity is not strong enough to elicit physiological responses.

Antiosteoclastic activity of milk thistle extract after ovariectomy to suppress estrogen deficiency-induced osteoporosis

Bone integrity abnormality and imbalance between bone formation by osteoblasts and bone resorption by osteoclasts are known to result in metabolic bone diseases such as osteoporosis. Silymarin-rich milk thistle extract (MTE) and its component silibinin enhanced alkaline phosphatase activity of osteoblasts but reduced tartrate-resistant acid phosphatase (TRAP) activity of osteoclasts. The osteoprotective effects of MTE were comparable to those of estrogenic isoflavone. Low-dose combination of MTE and isoflavone had a pharmacological synergy that may be useful for osteogenic activity. This study attempted to reveal the suppressive effects of MTE on bone loss. C57BL/6 female mice were ovariectomized (OVX) as a model for postmenopausal osteopenia and orally administered 10 mg/kg MTE or silibinin for 8 weeks. The sham-operated mice served as estrogen controls. The treatment of ovariectomized mice with nontoxic MTE and silibinin improved femoral bone mineral density and serum receptor activator of nuclear factor- κB ligand/osteoprotegerin ratio, an index of osteoclastogenic stimulus. In addition, the administration of MTE or silibinin inhibited femoral bone loss induced by ovariectomy and suppressed femoral TRAP activity and cathepsin K induction responsible for osteoclastogenesis and bone resorption. Collectively, oral dosage of MTE containing silibinin in the preclinical setting is effective in preventing estrogen deficiency-induced bone loss.

Non-genomic effects of xenoestrogen mixtures

Xenoestrogens (XEs) are chemicals derived from a variety of natural and anthropogenic sources that can interfere with endogenous estrogens by either mimicking or blocking their responses via non-genomic and/or genomic signaling mechanisms. Disruption of estrogens' actions through the less-studied non-genomic pathway can alter such functional end points as cell proliferation, peptide hormone release, catecholamine transport, and apoptosis, among others. Studies of potentially adverse effects due to mixtures and to low doses of endocrine-disrupting chemicals have recently become more feasible, though few so far have included actions via the non-genomic pathway. Physiologic estrogens and XEs evoke non-monotonic dose responses, with different compounds having different patterns of actions dependent on concentration and time, making mixture assessments all the more challenging. In order to understand the spectrum of toxicities and their mechanisms, future work should focus on carefully studying individual and mixture components across a range of concentrations and cellular pathways in a variety of tissue types.