RESUMO
Botanical dietary supplements (BDS) containing hops are sold as women's health supplements due to the potent hop phytoestrogen, 8-prenylnaringenin (8-PN), and the cytoprotective chalcone, xanthohumol. Previous studies have shown a standardized hop extract to beneficially influence chemical estrogen carcinogenesis in vitro by fostering detoxified 2-hydroxylation over genotoxic 4-hydroxylation estrogen metabolism. In this study, hop extract and its bioactive compounds were investigated for its mechanism of action within the chemical estrogen carcinogenesis pathway, which is mainly mediated through the 4-hydroxylation pathway catalyzed by CYP1B1 that can form gentoxic quinones. Aryl hydrocarbon receptor (AhR) agonists induce CYP1A1 and CYP1B1, while estrogen receptor alpha (ERα) inhibits transcription of CYP1A1, the enzyme responsible for 2-hydroxylated estrogens and the estrogen detoxification pathway. An In-Cell Western MCF-7 cell assay revealed hop extract and 6-prenylnaringenin (6-PN) degraded ERα via an AhR-dependent mechanism. Reverse transcription PCR and xenobiotic response element luciferase assays showed hop extract and 6-PN-mediated activation of AhR and induction of CYP1A1. A reduction in estrogen-mediated DNA (cytosine-5)-methyltransferase 1 (DNMT1) downregulation of CYP1A1 accompanied this activity in a chromatin immunoprecipitation assay. Ultimately, hop extract and 6-PN induced preferential metabolism of estrogens to their detoxified form in vitro. These results suggest that the standardized hop extract and 6-PN activate AhR to attenuate epigenetic inhibition of CYP1A1 through degradation of ERα, ultimately increasing 2-hydroxylated estrogens. A new mechanism of action rationalizes the positive influence of hop BDS and 6-PN on oxidative estrogen metabolism in vitro and, thus, potentially on chemical estrogen carcinogenesis. The findings underscore the importance of elucidating various biological mechanisms of action and standardizing BDS to multiple phytoconstituents for optimal resilience promoting properties.
Assuntos
Citocromo P-450 CYP1A1/antagonistas & inibidores , Regulação para Baixo/efeitos dos fármacos , Receptor alfa de Estrogênio/antagonistas & inibidores , Estrogênios/efeitos adversos , Flavonoides/farmacologia , Humulus/química , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Receptor alfa de Estrogênio/metabolismo , Feminino , Flavonoides/química , Flavonoides/isolamento & purificação , Humanos , Células Tumorais CultivadasRESUMO
Botanical dietary supplements for women's health are increasingly popular. Older women tend to take botanical supplements such as hops as natural alternatives to traditional hormone therapy to relieve menopausal symptoms. Especially extracts from spent hops, the plant material remaining after beer brewing, are enriched in bioactive prenylated flavonoids that correlate with the health benefits of the plant. The chalcone xanthohumol (XH) is the major prenylated flavonoid in spent hops. Other less abundant but important bioactive prenylated flavonoids are isoxanthohumol (IX), 8-prenylnaringenin (8-PN), and 6-prenylnaringenin (6-PN). Pharmacokinetic studies revealed that these flavonoids are conjugated rapidly with glucuronic acid. XH also undergoes phase I metabolism in vivo to form IX, 8-PN, and 6-PN. Several hop constituents are responsible for distinct effects linked to multiple biological targets, including hormonal, metabolic, inflammatory, and epigenetic pathways. 8-PN is one of the most potent phytoestrogens and is responsible for hops' estrogenic activities. Hops also inhibit aromatase activity, which is linked to 8-PN. The weak electrophile, XH, can activate the Keap1-Nrf2 pathway and turn on the synthesis of detoxification enzymes such as NAD(P)H-quinone oxidoreductase 1 and glutathione S-transferase. XH also alkylates IKK and NF-κB, resulting in anti-inflammatory activity. Antiobesity activities have been described for XH and XH-rich hop extracts likely through activation of AMP-activated protein kinase signaling pathways. Hop extracts modulate the estrogen chemical carcinogenesis pathway by enhancing P450 1A1 detoxification. The mechanism appears to involve activation of the aryl hydrocarbon receptor (AhR) by the AhR agonist, 6-PN, leading to degradation of the estrogen receptor. Finally, prenylated phenols from hops are known inhibitors of P450 1A1/2; P450 1B1; and P450 2C8, 2C9, and 2C19. Understanding the biological targets of hop dietary supplements and their phytoconstituents will ultimately lead to standardized botanical products with higher efficacy, safety, and chemopreventive properties.
Assuntos
Flavonoides/química , Humulus/química , Proteínas Quinases Ativadas por AMP/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Feminino , Flavonoides/metabolismo , Flavonoides/farmacologia , Humanos , Humulus/metabolismo , Extratos Vegetais/química , Receptores de Hidrocarboneto Arílico/química , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Estrogênio/química , Receptores de Estrogênio/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Botanical dietary supplements are increasingly popular for women's health, particularly for older women. The specific botanicals women take vary as a function of age. Younger women will use botanicals for urinary tract infections, especially Vaccinium macrocarpon (cranberry), where there is evidence for efficacy. Botanical dietary supplements for premenstrual syndrome (PMS) are less commonly used, and rigorous clinical trials have not been done. Some examples include Vitex agnus-castus (chasteberry), Angelica sinensis (dong quai), Viburnum opulus/prunifolium (cramp bark and black haw), and Zingiber officinale (ginger). Pregnant women have also used ginger for relief from nausea. Natural galactagogues for lactating women include Trigonella foenum-graecum (fenugreek) and Silybum marianum (milk thistle); however, rigorous safety and efficacy studies are lacking. Older women suffering menopausal symptoms are increasingly likely to use botanicals, especially since the Women's Health Initiative showed an increased risk for breast cancer associated with traditional hormone therapy. Serotonergic mechanisms similar to antidepressants have been proposed for Actaea/Cimicifuga racemosa (black cohosh) and Valeriana officinalis (valerian). Plant extracts with estrogenic activities for menopausal symptom relief include Glycine max (soy), Trifolium pratense (red clover), Pueraria lobata (kudzu), Humulus lupulus (hops), Glycyrrhiza species (licorice), Rheum rhaponticum (rhubarb), Vitex agnus-castus (chasteberry), Linum usitatissimum (flaxseed), Epimedium species (herba Epimedii, horny goat weed), and Medicago sativa (alfalfa). Some of the estrogenic botanicals have also been shown to have protective effects against osteoporosis. Several of these botanicals could have additional breast cancer preventive effects linked to hormonal, chemical, inflammatory, and/or epigenetic pathways. Finally, although botanicals are perceived as natural safe remedies, it is important for women and their healthcare providers to realize that they have not been rigorously tested for potential toxic effects and/or drug/botanical interactions. Understanding the mechanism of action of these supplements used for women's health will ultimately lead to standardized botanical products with higher efficacy, safety, and chemopreventive properties.
RESUMO
Postmenopausal women are increasingly using botanicals for menopausal symptom relief due to the increased breast cancer risk associated with traditional estrogen therapy. The deleterious effects of estrogens are associated with estrogen receptor (ER)α-dependent proliferation, while ERß activation could enhance safety by opposing ERα effects. Three medicinal licorice species, Glycyrrhiza glabra ( G. glabra), G. uralensis, and G. inflata, were studied for their differential estrogenic efficacy. The data showed higher estrogenic potency for G. inflata in an alkaline phosphatase induction assay in Ishikawa cells (ERα) and an estrogen responsive element (ERE)-luciferase assay in MDA-MB-231/ß41 breast cancer cells (ERß). Bioassay-guided fractionation of G. inflata led to the isolation of 8-prenylapigenin (3). Surprisingly, a commercial batch of 3 was devoid of estrogenic activity. Quality control by MS and qNMR revealed an incorrect compound, 4'- O-methylbroussochalcone B (10), illustrating the importance of both structural and purity verification prior to any biological investigations. Authentic and pure 3 displayed 14-fold preferential ERß agonist activity. Quantitative analyses revealed that 3 was 33 times more concentrated in G. inflata compared to the other medicinal licorice extracts. These data suggest that standardization of G. inflata to 3 might enhance the safety and efficacy of G. inflata supplements used for postmenopausal women's health.
Assuntos
Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Flavonas/farmacologia , Glycyrrhiza/química , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Chalconas/farmacologia , Receptor beta de Estrogênio/agonistas , Estrogênios/metabolismo , Feminino , Humanos , Extratos Vegetais/farmacologiaRESUMO
BACKGROUND: Impairment of central auditory processing is a well-known symptom of neurodegenerative dementia; however, whilst numerous studies have examined verbal processing impairment, to date few have attempted to describe impairments of non-verbal, environmental sound recognition in patients with dementia. As these impairments may have direct implications on patient support and care, such studies are urgently necessary. AIM OF THE STUDY: The aim of the study was to determine whether the recognition of meaningful environmental sounds is impaired in patients with mild or early stage neurodegenerative dementia. PATIENTS AND METHODS: We developed a test of non-verbal sound recognition consisting of 16 sound sequences from the familiar and unfamiliar environments. We included 18 patients with mild cognitive impairment and mild dementia caused by Alzheimer's disease and frontotemporal dementia, as well as 20 cognitively healthy controls. RESULTS: Patients and controls were given the test of recognizing 16 meaningful sounds from the familiar and unfamiliar environments. Patients with dementia performed significantly worse in comparison to cognitively healthy controls. Whilst healthy controls correctly recognized on average 12.1 ± 2.2 out of 16 sounds, cognitively impaired patients recognized 9.2 ± 2.5. Correlation analysis showed that the mini mental state examination (MMSE) scores were positively correlated with the number of correctly recognized sounds (MMSE: r = 0.556, p = 0.017). DISCUSSION: The fact that even in mild stages of Alzheimer's disease or frontotemporal dementia patients either do not recognize or misinterpret environmental sounds must be taken into consideration not only in everyday life but in particular when patients need to leave their familiar living environment, whether temporarily (e. g. hospitalization) or permanently (e. g. nursing home admission).
Assuntos
Doença de Alzheimer/complicações , Percepção Auditiva/fisiologia , Transtornos da Percepção Auditiva/etiologia , Disfunção Cognitiva/complicações , Demência/complicações , Meio Ambiente , Transtornos da Audição/etiologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Estudos de Casos e Controles , Disfunção Cognitiva/fisiopatologia , Demência/fisiopatologia , Feminino , Humanos , Masculino , Testes NeuropsicológicosRESUMO
Many women consider botanical dietary supplements (BDSs) as safe alternatives to hormone therapy for menopausal symptoms. However, the effect of BDSs on breast cancer risk is largely unknown. In the estrogen chemical carcinogenesis pathway, P450 1B1 metabolizes estrogens to 4-hydroxylated catechols, which are oxidized to genotoxic quinones that initiate and promote breast cancer. In contrast, P450 1A1 catalyzed 2-hydroxylation represents a detoxification pathway. The current study evaluated the effects of red clover, a popular BDS used for women's health, and its isoflavones, biochanin A (BA), formononetin (FN), genistein (GN), and daidzein (DZ), on estrogen metabolism. The methoxy estrogen metabolites (2-MeOE1, 4-MeOE1) were measured by LC-MS/MS, and CYP1A1 and CYP1B1 gene expression was analyzed by qPCR. Nonmalignant ER-negative breast epithelial cells (MCF-10A) and ER-positive breast cancer cells (MCF-7) were derived from normal breast epithelial tissue and ER+ breast cancer tissue. Red clover extract (RCE, 10 µg/mL) and isoflavones had no effect on estrogen metabolism in MCF-10A cells. However, in MCF-7 cells, RCE treatments downregulated CYP1A1 expression and enhanced genotoxic metabolism (4-MeOE1/CYP1B1 > 2-MeOE1/CYP1A1). Experiments with the isoflavones showed that the AhR agonists (BA, FN) preferentially induced CYP1B1 expression as well as 4-MeOE1. In contrast, the ER agonists (GN, DZ) downregulated CYP1A1 expression likely through an epigenetic mechanism. Finally, the ER antagonist ICI 182,780 potentiated isoflavone-induced XRE-luciferase reporter activity and reversed GN and DZ induced downregulation of CYP1A1 expression. Overall, these studies show that red clover and its isoflavones have differential effects on estrogen metabolism in "normal" vs breast cancer cells. In breast cancer cells, the AhR agonists stimulate genotoxic metabolism, and the ER agonists downregulate the detoxification pathway. These data may suggest that especially breast cancer patients should avoid red clover and isoflavone based BDSs when making choices for menopausal symptom relief.
Assuntos
Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/metabolismo , Suplementos Nutricionais/efeitos adversos , Estrogênios/metabolismo , Isoflavonas/efeitos adversos , Receptores de Hidrocarboneto Arílico/metabolismo , Trifolium/metabolismo , Mama/efeitos dos fármacos , Mama/metabolismo , Neoplasias da Mama/genética , Carcinogênese/metabolismo , Linhagem Celular , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1/genética , Suplementos Nutricionais/análise , Feminino , Humanos , Isoflavonas/análise , Isoflavonas/metabolismo , Células MCF-7RESUMO
Botanical dietary supplements contain multiple bioactive compounds that target numerous biological pathways. The lack of uniform standardization requirements is one reason that inconsistent clinical effects are reported frequently. The multifaceted biological interactions of active principles can be disentangled by a coupled pharmacological/phytochemical approach using specialized ("knock-out") extracts. This is demonstrated for hops, a botanical for menopausal symptom management. Employing targeted, adsorbent-free countercurrent separation, Humulus lupulus extracts were designed for pre- and postmenopausal women by containing various amounts of the phytoestrogen 8-prenylnaringenin (8-PN) and the chemopreventive constituent xanthohumol (XH). Analysis of their estrogenic (alkaline phosphatase), chemopreventive (NAD(P)H-quinone oxidoreductase 1 [NQO1]), and cytotoxic bioactivities revealed that the estrogenicity of hops is a function of 8-PN, whereas their NQO1 induction and cytotoxic properties depend on XH levels. Antagonization of the estrogenicity of 8-PN by elevated XH concentrations provided evidence for the interdependence of the biological effects. A designed postmenopausal hop extract was prepared to balance 8-PN and XH levels for both estrogenic and chemopreventive properties. An extract designed for premenopausal women contains reduced 8-PN levels and high XH concentrations to minimize estrogenic while retaining chemopreventive properties. This study demonstrates the feasibility of modulating the concentrations of bioactive compounds in botanical extracts for potentially improved efficacy and safety.
Assuntos
Estrogênios/metabolismo , Flavanonas/isolamento & purificação , Flavanonas/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacocinética , Humulus/química , Fitoestrógenos/isolamento & purificação , Fitoestrógenos/farmacologia , Propiofenonas/isolamento & purificação , Propiofenonas/farmacocinética , Suplementos Nutricionais , Estrogênios/química , Feminino , Flavanonas/química , Flavonoides/química , Humanos , Estrutura Molecular , Fitoestrógenos/química , Propiofenonas/química , Saúde da MulherRESUMO
Humulus lupulus L. (hops) is a popular botanical dietary supplement used by women as a sleep aid and for postmenopausal symptom relief. In addition to its efficacy for menopausal symptoms, hops can also modulate the chemical estrogen carcinogenesis pathway and potentially protect women from breast cancer. In the present study, an enriched hop extract and the key bioactive compounds [6-prenylnarigenin (6-PN), 8-prenylnarigenin (8-PN), isoxanthohumol (IX), and xanthohumol (XH)] were tested for their effects on estrogen metabolism in breast cells (MCF-10A and MCF-7). The methoxyestrones (2-/4-MeOE1) were analyzed as biomarkers for the nontoxic P450 1A1 catalyzed 2-hydroxylation and the genotoxic P450 1B1 catalyzed 4-hydroxylation pathways, respectively. The results indicated that the hop extract and 6-PN preferentially induced the 2-hydroxylation pathway in both cell lines. 8-PN only showed slight up-regulation of metabolism in MCF-7 cells, whereas IX and XH did not have significant effects in either cell line. To further explore the influence of hops and its bioactive marker compounds on P450 1A1/1B1, mRNA expression and ethoxyresorufin O-dealkylase (EROD) activity were measured. The results correlated with the metabolism data and showed that hop extract and 6-PN preferentially enhanced P450 1A1 mRNA expression and increased P450 1A1/1B1 activity. The aryl hydrocarbon receptor (AhR) activation by the isolated compounds was tested using xenobiotic response element (XRE) luciferase construct transfected cells. 6-PN was found to be an AhR agonist that significantly induced XRE activation and inhibited 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced XRE activity. 6-PN mediated induction of EROD activity was also inhibited by the AhR antagonist CH223191. These data show that the hop extract and 6-PN preferentially enhance the nontoxic estrogen 2-hydroxylation pathway through AhR mediated up-regulation of P450 1A1, which further emphasizes the importance of standardization of botanical extracts to multiple chemical markers for both safety and desired bioactivity.
Assuntos
Citocromo P-450 CYP1A1/biossíntese , Estrogênios/metabolismo , Flavonoides/farmacologia , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1A1/metabolismo , Feminino , Humanos , Humulus/química , Hidroxilação , RNA Mensageiro/genéticaRESUMO
The avoidance of wheat, gluten and other cereal products is a growing phenomenon in industrialized countries. The diagnostic criteria of celiac disease and of food allergy to wheat flour and/or other cereals are clearly defined. Only about 0.5-25 % of the population are affected from both of these immunological diseases.Nevertheless, there exists a significantly greater proportion of people reporting at least subjectively significant complaints and quality of life improvements after switching to a wheat- or gluten-free diet. Celiac disease or wheat allergy cannot be detected in these individuals on the basis of established criteria. The absence of clear diagnostic autoimmune or allergic criteria in these wheat sensitive patients has resulted in the description of non-celiac gluten sensitivity.It is clinically detectable in only very few individuals and may manifest with either intestinal, extra-intestinal or neurovegetative and psychosomatic symptoms, respectively. However, non-celiac disease gluten sensitivity has to be differentiated critically from irritable bowel syndrome, carbohydrate malassimilation, postinfectious conditions and psychosomatic diseases.Pathophysiologically, non-celiac disease gluten sensitivity is still poorly characterized; several non-immunological mechanisms are discussed to contribute to non-celiac gluten sensitivity. These include the effects of fructo- and galacto-oligosaccharides, of trypsin inhibitors of amylase, and wheat lectin agglutinins, which may influence or modulate intestinal permeability and/or a non-specific immune or effector cell degranulation within the gastrointestinal tract. In addition, further metabolic effects with direct or indirect influence on the intestinal flora are currently discussed.In addition to subjectively reported changes in symptoms that may affect variably intestinal, as well as extra-intestinal and/or neuropsychiatric symptoms, some studies suggest that there is little reproducibility of complaints from gluten exposure. For a definitive diagnosis of non-celiac gluten sensitivity, structured (blinded) challenge tests with wheat or gluten are mandatory as well as re-challenge after a defined time of gluten avoidance to establish non-celiac disease gluten sensitivity as a persistent disease entity.
Assuntos
Doença Celíaca/diagnóstico , Doença Celíaca/imunologia , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade Alimentar/imunologia , Glutens/efeitos adversos , Glutens/imunologia , Doença Celíaca/classificação , Medicina Baseada em Evidências , Hipersensibilidade Alimentar/classificação , Humanos , Terminologia como AssuntoRESUMO
Estrogen chemical carcinogenesis involves 4-hydroxylation of estrone/estradiol (E1/E2) by P450 1B1, generating catechol and quinone genotoxic metabolites that cause DNA mutations and initiate/promote breast cancer. Inflammation enhances this effect by upregulating P450 1B1. The present study tested the three authenticated medicinal species of licorice [Glycyrrhiza glabra (GG), G. uralensis (GU), and G. inflata (GI)] used by women as dietary supplements for their anti-inflammatory activities and their ability to modulate estrogen metabolism. The pure compounds, liquiritigenin (LigF), its chalcone isomer isoliquiritigenin (LigC), and the GI-specific licochalcone A (LicA) were also tested. The licorice extracts and compounds were evaluated for anti-inflammatory activity by measuring inhibition of iNOS activity in macrophage cells: GI â« GG > GU and LigC â LicA â« LigF. The Michael acceptor chalcone, LicA, is likely responsible for the anti-inflammatory activity of GI. A sensitive LC-MS/MS assay was employed to quantify estrogen metabolism by measuring 2-MeOE1 as nontoxic and 4-MeOE1 as genotoxic biomarkers in the nontumorigenic human mammary epithelial cell line, MCF-10A. GG, GU, and LigC increased 4-MeOE1, whereas GI and LicA inhibited 2- and 4-MeOE1 levels. GG, GU (5 µg/mL), and LigC (1 µM) also enhanced P450 1B1 expression and activities, which was further increased by inflammatory cytokines (TNF-α and IFN-γ). LicA (1, 10 µM) decreased cytokine- and TCDD-induced P450 1B1 gene expression and TCDD-induced xenobiotic response element luciferase reporter (IC50 = 12.3 µM), suggesting an antagonistic effect on the aryl hydrocarbon receptor, which regulates P450 1B1. Similarly, GI (5 µg/mL) reduced cytokine- and TCDD-induced P450 1B1 gene expression. Collectively, these data suggest that, of the three licorice species that are used in botanical supplements, GI represents the most promising chemopreventive licorice extract for women's health. Additionally, the differential effects of the Glycyrrhiza species on estrogen metabolism emphasize the importance of standardization of botanical supplements to species-specific bioactive compounds.
Assuntos
Neoplasias da Mama , Chalconas/farmacologia , Citocromo P-450 CYP1A1/genética , Estrogênios/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glycyrrhiza/química , Cromatografia Líquida , Citocromo P-450 CYP1A1/metabolismo , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Macrófagos/citologia , Modelos Biológicos , Preparações de Plantas/farmacologia , Especificidade da Espécie , Regulação para Cima/efeitos dos fármacosRESUMO
For the alleviation of menopausal symptoms, women frequently turn to botanical dietary supplements, such as licorice and hops. In addition to estrogenic properties, these botanicals could also have chemopreventive effects. We have previously shown that hops and its Michael acceptor xanthohumol (XH) induced the chemoprevention enzyme, NAD(P)H: quinone oxidoreductase 1 (NQO1), in vitro and in vivo. Licorice species could also induce NQO1, as they contain the Michael acceptors isoliquiritigenin (LigC) found in Glycyrrhiza glabra (GG), G. uralensis (GU), G. inflata (GI), and licochalcone A (LicA) which is only found in GI. These licorice species and hops induced NQO1 activity in murine hepatoma (Hepa1c1c7) cells; hops â« GI > GG â GU. Similar to the known chemopreventive compounds curcumin (turmeric), sulforaphane (broccoli), and XH, LigC and LicA were active dose-dependently; sulforaphane â« XH > LigC > LicA â curcumin â« liquiritigenin (LigF). Induction of the antioxidant response element luciferase in human hepatoma (HepG2-ARE-C8) cells suggested involvement of the Keap1-Nrf2 pathway. GG, GU, and LigC also induced NQO1 in nontumorigenic breast epithelial MCF-10A cells. In female Sprague-Dawley rats treated with GG and GU, LigC and LigF were detected in the liver and mammary gland. GG weakly enhanced NQO1 activity in the mammary tissue but not in the liver. Treatment with LigC alone did not induce NQO1 in vivo most likely due to its conversion to LigF, extensive metabolism, and its low bioavailability in vivo. These data show the chemopreventive potential of licorice species in vitro could be due to LigC and LicA and emphasize the importance of chemical and biological standardization of botanicals used as dietary supplements. Although the in vivo effects in the rat model after four-day treatment are minimal, it must be emphasized that menopausal women take these supplements for extended periods of time and long-term beneficial effects are quite possible.
Assuntos
Chalconas/farmacologia , Glycyrrhiza , NAD(P)H Desidrogenase (Quinona)/metabolismo , Extratos Vegetais/farmacologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Glândulas Mamárias Animais/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Camundongos , Ratos Sprague-Dawley , Saúde da MulherRESUMO
Concerned about the safety of conventional estrogen replacement therapy, women are using botanical dietary supplements as alternatives for the management of menopausal symptoms such as hot flashes. Before botanical dietary supplements can be evaluated clinically for safety and efficacy, botanically authenticated and standardized forms are required. To address the demand for a standardized, estrogenic botanical dietary supplement, an extract of hops (Humulus lupulus L.) was developed. Although valued in the brewing of beer, hop extracts are used as anxiolytics and hypnotics and have well-established estrogenic constituents. Starting with a hop cultivar used in the brewing industry, spent hops (the residue remaining after extraction of bitter acids) were formulated into a botanical dietary supplement that was then chemically and biologically standardized. Biological standardization utilized the estrogen-dependent induction of alkaline phosphatase in the Ishikawa cell line. Chemical standardization was based on the prenylated phenols in hops that included estrogenic 8-prenylnaringenin, its isomer 6-prenylnaringenin, and pro-estrogenic isoxanthohumol and its isomeric chalcone xanthohumol, all of which were measured using high-performance liquid chromatography-tandem mass spectrometry. The product of this process was a reproducible botanical extract suitable for subsequent investigations of safety and efficacy.
Assuntos
Suplementos Nutricionais/normas , Estrogênios/química , Estrogênios/normas , Humulus/química , Extratos Vegetais/química , Extratos Vegetais/normas , Linhagem Celular , Suplementos Nutricionais/análise , Estrogênios/farmacologia , Feminino , Humanos , Extratos Vegetais/farmacologiaRESUMO
Menopausal women suffer from a variety of symptoms, including hot flashes and night sweats, which can affect quality of life. Although it has been the treatment of choice for relieving these symptoms, hormone therapy has been associated with increased breast cancer risk leading many women to search for natural, efficacious, and safe alternatives such as botanical supplements. Data from clinical trials suggesting that botanicals have efficacy for menopausal symptom relief have been controversial, and several mechanisms of action have been proposed including estrogenic, progestogenic, and serotonergic pathways. Plant extracts with potential estrogenic activities include soy, red clover, kudzu, hops, licorice, rhubarb, yam, and chasteberry. Botanicals with reported progestogenic activities are red clover, hops, yam, and chasteberry. Serotonergic mechanisms have also been proposed since women taking antidepressants often report a reduction in hot flashes and night sweats. Black cohosh, kudzu, kava, licorice, and dong quai all either have reported 5-hydroxytryptamine receptor 7 ligands or inhibit serotonin reuptake, therefore have potential serotonergic activities. Understanding the mechanisms of action of these natural remedies used for women's health could lead to more efficacious formulations and to the isolation of active components which have the potential of becoming effective medications in the future.
Assuntos
Magnoliopsida , Menopausa , Fitoestrógenos/farmacologia , Fitoterapia , Extratos Vegetais/farmacologia , Progestinas/farmacologia , Agonistas do Receptor de Serotonina/farmacologia , Feminino , Fogachos/tratamento farmacológico , Humanos , Ligantes , Fitoestrógenos/uso terapêutico , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Progestinas/uso terapêutico , Receptores de Serotonina/metabolismo , Agonistas do Receptor de Serotonina/uso terapêutico , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Sudorese/efeitos dos fármacos , Saúde da MulherRESUMO
Breast cancer risk continues to increase post menopause. Anti-estrogen therapies are available to prevent postmenopausal breast cancer in high-risk women. However, their adverse effects have reduced acceptability and overall success in cancer prevention. Natural products such as hops (Humulus lupulus) and three pharmacopeial licorice (Glycyrrhiza) species have demonstrated estrogenic and chemopreventive properties, but little is known regarding their effects on aromatase expression and activity as well as pro-proliferation pathways in human breast tissue. We show that Gycyrrhiza inflata (GI) has the highest aromatase inhibition potency among these plant extracts. Moreover, phytoestrogens such as liquiritigenin which is common in all licorice species have potent aromatase inhibitory activity, which is further supported by computational docking of their structures in the binding pocket of aromatase. In addition, GI extract and liquiritigenin suppress aromatase expression in the breast tissue of high-risk postmenopausal women. Although liquiritigenin has estrogenic effects in vitro, with preferential activity through estrogen receptor (ER)-ß, it reduces estradiol-induced uterine growth in vivo. It downregulates RNA translation, protein biosynthesis, and metabolism in high-risk women's breast tissue. Finally, it reduces the rate of MCF-7 cell proliferation, with repeated dosing. Collectively, these data suggest that liquiritigenin has breast cancer prevention potential for high-risk postmenopausal women.
Assuntos
Neoplasias da Mama , Glycyrrhiza , Feminino , Humanos , Neoplasias da Mama/prevenção & controle , Neoplasias da Mama/metabolismo , Aromatase/metabolismo , Inibidores da Aromatase/farmacologia , Estrogênios/metabolismo , Glycyrrhiza/química , Receptor beta de Estrogênio/metabolismo , Biossíntese de ProteínasRESUMO
In botanical extracts, highly abundant constituents can mask or dilute the effects of other, and often, more relevant biologically active compounds. To facilitate the rational chemical and biological assessment of these natural products with wide usage in human health, we introduced the DESIGNER approach of Depleting and Enriching Selective Ingredients to Generate Normalized Extract Resources. The present study applied this concept to clinical Red Clover Extract (RCE) and combined phytochemical and biological methodology to help rationalize the utility of RCE supplements for symptom management in postmenopausal women. Previous work has demonstrated that RCE reduces estrogen detoxification pathways in breast cancer cells (MCF-7) and, thus, may serve to negatively affect estrogen metabolism-induced chemical carcinogenesis. Clinical RCE contains ca. 30% of biochanin A and formononetin, which potentially mask activities of less abundant compounds. These two isoflavonoids are aryl hydrocarbon receptor (AhR) agonists that activate P450 1A1, responsible for estrogen detoxification, and P450 1B1, producing genotoxic estrogen metabolites in female breast cells. Clinical RCE also contains the potent phytoestrogen, genistein, that downregulates P450 1A1, thereby reducing estrogen detoxification. To identify less abundant bioactive constituents, countercurrent separation (CCS) of a clinical RCE yielded selective lipophilic to hydrophilic metabolites in six enriched DESIGNER fractions (DFs 01-06). Unlike solid-phase chromatography, CCS prevented any potential loss of minor constituents or residual complexity (RC) and enabled the polarity-based enrichment of certain constituents. Systematic analysis of estrogen detoxification pathways (ERα-degradation, AhR activation, CYP1A1/CYP1B1 induction and activity) of the DFs uncovered masked bioactivity of minor/less abundant constituents including irilone. These data will allow the optimization of RCE with respect to estrogen detoxification properties. The DFs revealed distinct biological activities between less abundant bioactives. The present results can inspire future carefully designed extracts with phytochemical profiles that are optimized to increase in estrogen detoxification pathways and, thereby, promote resilience in women with high-risk for breast cancer. The DESIGNER approach helps to establish links between complex chemical makeup, botanical safety and possible efficacy parameters, yields candidate DFs for (pre)clinical studies, and reveals the contribution of minor phytoconstituents to the overall safety and bioactivity of botanicals, such as resilience promoting activities relevant to women's health.
Assuntos
Neoplasias da Mama , Isoflavonas , Trifolium , Feminino , Humanos , Trifolium/química , Trifolium/metabolismo , Isoflavonas/farmacologia , Isoflavonas/metabolismo , Estrogênios , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Neoplasias da Mama/tratamento farmacológicoRESUMO
Breast cancer risk has been associated with long-term estrogen exposure including traditional hormone therapy (HT, formally hormone replacement therapy). To avoid traditional HT and associated risks, women have been turning to botanical supplements such as black cohosh, red clover, licorice, hops, dong gui, and ginger to relieve menopausal symptoms despite a lack of efficacy evidence. The mechanisms of estrogen carcinogenesis involve both hormonal and chemical pathways. Botanical supplements could protect women from estrogen carcinogenesis by modulating key enzymatic steps [aromatase, P4501B1, P4501A1, catechol-O-methyltransferase (COMT), NAD(P)H quinone oxidoreductase 1 (NQO1), and reactive oxygen species (ROS) scavenging] in estradiol metabolism leading to estrogen carcinogenesis as outlined in Figure 1. This review summarizes the influence of popular botanical supplements used for women's health on these key steps in the estrogen chemical carcinogenesis pathway, and suggests that botanical supplements may have added chemopreventive benefits by modulating estrogen metabolism.
RESUMO
Optimal parameters for the auto-hydrolysis of (iso)flavone glycosides to aglycones in ground Trifolium pratense L. plant material were established as a "green" method for the production of a reproducible red clover extract (RCE). The process utilized 72-h fermentation in DI water at 25 and 37 °C. The aglycones obtained at 25 °C, as determined by UHPLC-UV and quantitative 1H NMR (qHNMR), increased significantly in the auto-hydrolyzed (ARCE) (6.2-6.7% w/w biochanin A 1, 6.1-9.9% formononetin 2) vs a control ethanol (ERCE) extract (0.24% 1, 0.26% 2). After macerating ARCE with 1:1 (v/v) diethyl ether/hexanes (ARCE-d/h), 1 and 2 increased to 13.1-16.7% and 14.9-18.4% w, respectively, through depletion of fatty components. The final extracts showed chemical profiles similar to that of a previous clinical RCE. Biological standardization revealed that the enriched ARCE-d/h extracts produced the strongest estrogenic activity in ERα positive endometrial cells (Ishikawa cells), followed by the precursor ARCE. The glycoside-rich ERCE showed no estrogenic activity. The estrogenicity of ARCE-d/h was similar to that of the clinical RCE. The lower potency of the ARCE compared to the prior clinical RCE indicated that substantial amounts of fatty acids/matter likely reduce the estrogenicity of crude hydrolyzed preparations. The in vitro dynamic residual complexity of the conversion of biochanin A to genistein was evaluated by LC-MS-MS. The outcomes help advance translational research with red clover and other (iso)flavone-rich botanicals by inspiring the preparation of (iso)flavone aglycone-enriched extracts for the exploration of new in vitro and ex vivo bioactivities that are unachievable with genuine, glycoside-containing extracts.
Assuntos
Flavonoides/química , Extratos Vegetais/química , Trifolium/química , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Humanos , Hidrólise , Compostos Fitoquímicos/química , Fitoestrógenos/química , Componentes Aéreos da Planta/química , SolventesRESUMO
A new isoflavonoid, xanthocerin J, along with previously described xanthocerin A, were isolated from a methanol extract of aerial parts of a traditional American Indian herb, Amorpha canescens Pursh (Asteraceae). The structures of these compounds were characterized using mass spectrometry and NMR based on an isolation protocol using magnetic microbead affinity selection screening (MagMASS) for ligands to the estrogen receptor alpha (ERα). These compounds bound to ERα from an active fraction that exhibited dose-dependent antiestrogenic activity in the in vitro Ishikawa assay. However, these compounds did not exhibit antiestrogenic activity in the cell-based Ishikawa assay. Xanthocerin A and J may exhibit synergistic or additive activity with other compounds found in A. canescens which needs further exploration. This work highlights the potential of A. canescens as a prospect for the future discovery of compounds for women's health related to estrogen pathways.
RESUMO
Many botanicals used for women's health contain estrogenic (iso)flavonoids. The literature suggests that estrogen receptor beta (ERß) activity can counterbalance estrogen receptor alpha (ERα)-mediated proliferation, thus providing a better safety profile. A structure-activity relationship study of (iso)flavonoids was conducted to identify ERß-preferential structures, overall estrogenic activity, and ER subtype estrogenic activity of botanicals containing these (iso)flavonoids. Results showed that flavonoids with prenylation on C8 position increased estrogenic activity. C8-prenylated flavonoids with C2-C3 unsaturation resulted in increased ERß potency and selectivity [e.g., 8-prenylapigenin (8-PA), EC50 (ERß): 0.0035 ± 0.00040 µM], whereas 4'-methoxy or C3 hydroxy groups reduced activity [e.g., icaritin, EC50 (ERß): 1.7 ± 0.70 µM]. However, nonprenylated and C2-C3 unsaturated isoflavonoids showed increased ERß estrogenic activity [e.g., genistein, EC50 (ERß): 0.0022 ± 0.0004 µM]. Licorice (Glycyrrhiza inflata, [EC50 (ERα): 1.1 ± 0.20; (ERß): 0.60 ± 0.20 µg/mL], containing 8-PA, and red clover [EC50 (ERα): 1.8 ± 0.20; (ERß): 0.45 ± 0.10 µg/mL], with genistein, showed ERß-preferential activity as opposed to hops [EC50 (ERα): 0.030 ± 0.010; (ERß): 0.50 ± 0.050 µg/mL] and Epimedium sagittatum [EC50 (ERα): 3.2 ± 0.20; (ERß): 2.5 ± 0.090 µg/mL], containing 8-prenylnaringenin and icaritin, respectively. Botanicals with ERß-preferential flavonoids could plausibly contribute to ERß-protective benefits in menopausal women.