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Dieudonné Njamen - One of the best experts on this subject based on the ideXlab platform.
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Ethanol-extracted Cameroonian propolis exerts Estrogenic effects and alleviates hot flushes in ovariectomized Wistar rats
BMC Complementary and Alternative Medicine, 2017Co-Authors: Stéphane Zingue, Thomas Michel, Derek Tantoh Ndinteh, Jules Tchatchou, Moïse Adamou, Xavier Fernandez, Fernand-nestor Tchuenguem Fohouo, Colin Clyne, Dieudonné NjamenAbstract:Background Since the biological Properties of propolis depend to the plants that can be found in a specific region, propolis from unexplored regions attracts the attention of scientists. Ethanolic extract of Cameroonian propolis (EEP) is used to treat various ailments including gynecological problems and amenorrhea. Since there were no scientific data to support the above claims, the present study was therefore undertaken to assess Estrogenic Properties of Cameroonian propolis. Methods To achieve our goal, the ability of EEP to induce MCF-7 cells proliferation in E-screen assay as well as to activate estrogen receptors α (ERα) and β (ERβ) in cell-based reporter gene assays using human embryonic kidney cells (HEK293T) transfected with ERs was tested. Further, a 3-day uterotrophic assay was performed and the ability of EEP to alleviate hot flushes in ovariectomized adult rats was evaluated. Results In vitro, EEP showed an antiEstrogenic activity in both HEK293T ER-α and ER-β cells. In vivo, EEP induced a significant increase in a bell shape dose response manner of the uterine wet weight, the total protein levels in the uterus, the uterine and vaginal epithelium height and acini border cells of mammary gland with the presence of abundant eosinophil secretions. Moreover, EEP induced a significant decrease in the total number, average duration as well as frequency of hot flushes after 3 days of treatment in rat (equivalent to a month in woman). The dose of 150 mg/kg exhibited the most potent Estrogenic effects among all the tested doses. The UPLC-HRMS analysis showed the presence of caffeic acid derivatives and trirtepernoids in EEP, which are well known endowed with Estrogenic Properties. Conclusion These results suggest that Ethanolic extract of Cameroonian propolis has estrogen-like effects in vivo and may alleviate some menopausal problems such as vaginal dryness and hot flushes. Graphical abstract Ethanol-extracted Cameroobian propolis exhibited in vitro and in vivo estrogen-like effects. This extract may contain promising phytoestrogens.
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Evaluation of the Estrogenic Properties of aqueous extracts of Tragia benthamii Baker (Euphorbiaceae) and Graptophyllum pictum (Acanthaceae) and their ability to alleviate some menopausal symptoms induced by ovariectomy in Wistar rats
International Journal of Phytomedicine, 2016Co-Authors: Germain Jean Magloire Ketcha Wanda, Sefirin Djiogue, Sosthène Onésiphore Djoussi Njimfo, Charline Florence Awounfack, Dieudonné NjamenAbstract:Tragia benthamii Baker (Euphorbiaceae) and Graptophyllum pictum Linn (Acanthaceae) are two Cameroonian medicinal plants traditionally used against female reproductive tract disorders, during and after the reproductive period, and as an abortifacient. Since there were no scientific data supporting the above claims and pharmacological studies characterizing their Estrogenic Properties, we therefore aimed to evaluate their ability to induce estrogen-like effects on primary estrogens targets, uterine, vagina and mammary gland; as well as their ability to alleviate hot flushes in ovariectomized adult rats. For this purpose, we applied a 3-day uterotrophic assay to determine the Estrogenic effects of each extract and the mixture of both plants as used by traditional practitioners. The extracts were administered orally for 3 days to the 10 to 12 weeks aged ovariectomized rats. The results obtained showed that the aqueous extract of T. benthamii at the dose of 500 mg / kg BW, the aqueous extract of G. pictum at all the tested doses as well as the aqueous extract of the mixture at 275 mg / kg body weight induced a significant increase (p ˂ 0.01) of the uterine epithelium thickness. In addition, the aqueous extract of T. benthamii at the dose of 500 mg / kg BW, as well as the aqueous extract of the mixture at the doses of 50 and 275 mg / kg induced acinar development and eosinophil secretions. These results are proof of estrogen-like effects of T. benthamii and G. pictum and therefore justify the traditional use of these plants. This suggests the presence in these plants, of secondary metabolites with Estrogenic Properties, can induce cell proliferation, and to correct disorders of post-oophorectomy œstrogenopenia in the Wistar rats and therefore menopausal disorders.
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Estrogenic Properties of spices of the traditional Cameroonian dish "Nkui" in ovariectomized Wistar rats.
Journal of complementary & integrative medicine, 2016Co-Authors: Edwige Nana Tchoupang, Sylvin Benjamin Ateba, Stéphane Zingue, Martin Zehl, Liselotte Krenn, Dieudonné NjamenAbstract:BACKGROUND Besides the basic role to flavor and color foods, several health benefits have been attributed to spices. The traditional Cameroonian food "Nkui" is prepared using several spices (Afrostyrax lepidophyllus Mildbr., Capsicum frutescens Linn., Fagara leprieurii Guill. et Perr., Fagara tessmannii Engl., Mondia whitei Hook. F. Skell., Pentadiplandra brazzeana Baill., Solanum gilo Raddi., Tetrapleura tetraptera Taub. and Xylopia parviflora A. Rich. Benthane) that are believed to have a positive impact on the female reproductive physiology. Aiming to determine the potential effect of this food on the female reproductive tract, we evaluated the Estrogenic Properties of aqueous and ethanol extracts of Nkui using a 3-day uterotrophic assay in ovariectomized (OVX) rats. METHODS OVX female Wistar rats were randomly separated in several groups of five animals each and submitted to a 3-day uterotrophic assay (per os). At the end of treatment, animals were sacrificed and uterus, vagina and mammary gland collected and fixed in 10 % formalin for histological analysis. RESULTS These extracts increased the uterine wet weight, the uterine and vaginal epithelial heights, and the lumen and diameter of alveoli in the mammary glands. They also altered the estradiol-induced increase of uterine wet weight. The dichloromethane and methanol fractions of the ethanol extract exhibited Estrogenic Properties as well by increasing uterine and vaginal endpoints. CONCLUSIONS These results suggest that the spices of "Nkui" contain Estrogenic phytoconstituents and this traditional food may be considered as functional.
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The methanol-soluble fraction of Millettia macrophylla (Fabaceae) stem bark endowed with Estrogenic Properties has adverse effects on the male reproductive system of Wistar rats
Journal of basic and clinical physiology and pharmacology, 2015Co-Authors: Stéphane Zingue, Chantal Beatrice Magne Nde, Dieudonné NjamenAbstract:BACKGROUND The use of traditional medicinal plants to treat various diseases is common in Sub-Saharan African countries, including Cameroon. Millettia macrophylla, one of such plants, was previously found to exhibit Estrogenic Properties in female Wistar rats. However, its effects on the male reproductive system are unknown. Based on literature evidence that phytoestrogens impair male sexual behavior, we aimed at assessing the effect of the extracts of M. macrophylla stem bark on the male reproductive system of Wistar rats. MATERIALS AND METHODS We evaluated the effects of the dichloromethane (DCM) and methanol (MeOH) soluble fractions of M. macrophylla stem bark on male rat sexual behavior, as well as androgen-dependent parameters for 60 days. RESULTS Data showed a significant decrease (p
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the methanol soluble fraction of millettia macrophylla fabaceae stem bark endowed with Estrogenic Properties has adverse effects on the male reproductive system of wistar rats
Journal of basic and clinical physiology and pharmacology, 2015Co-Authors: Stéphane Zingue, Chantal Beatrice Magne Nde, Dieudonné NjamenAbstract:BACKGROUND The use of traditional medicinal plants to treat various diseases is common in Sub-Saharan African countries, including Cameroon. Millettia macrophylla, one of such plants, was previously found to exhibit Estrogenic Properties in female Wistar rats. However, its effects on the male reproductive system are unknown. Based on literature evidence that phytoestrogens impair male sexual behavior, we aimed at assessing the effect of the extracts of M. macrophylla stem bark on the male reproductive system of Wistar rats. MATERIALS AND METHODS We evaluated the effects of the dichloromethane (DCM) and methanol (MeOH) soluble fractions of M. macrophylla stem bark on male rat sexual behavior, as well as androgen-dependent parameters for 60 days. RESULTS Data showed a significant decrease (p<0.05) in the wiring-touch frequency, mount frequency, intromission frequency, ejaculatory frequency, penile-licking frequency, and computed indices of sexual behavior, throughout the experimental period, as well as a significant increase (p<0.001) in mount, intromission, and ejaculatory latencies as well as post-ejaculatory interval. Moreover, we observed a significant decrease (p<0.05) in the androgen-dependent sexual parameters evaluated. The DCM extract did not induce significant effects on the assessed parameters. CONCLUSIONS These results suggest that long-term exposure to the Estrogenic MeOH fraction of M. macrophylla stem bark negatively alters sexual behavior and spermatogenesis.
Günter Vollmer - One of the best experts on this subject based on the ideXlab platform.
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Estrogenic and anti-Estrogenic Properties of tropical African plants traditionally used in folk medicine
Planta Medica, 2015Co-Authors: K Ketterle, Günter Vollmer, J Miersch, Stefan Schwaiger, Hermann Stuppner, J WoberAbstract:An amazing diversity of traditionally used plants is found in the tropical areas of Africa and many of these plants have not or only insufficiently been studied. The purpose of this study was to evaluate eight African tropical plants, belonging to miscellaneous plant families, for Estrogenic and anti-Estrogenic Properties and to isolate and characterize single compounds obtained from these herbal extracts. Plant materials of Brillantaisia owariensis (BO), Palisota schweinfurthii (PS), Ricinodendron heudelotii ssp. africanum (RH), Thonningia sanguinea (TS), Hymenocardia ulmoides (HS), Garcinia mannii (GM), Alchornae cordifolia (AC), and Xylopium aethiopicum (XA) were extracted by methanol after defatting with petroleum ether. Experimentally, all extracts were tested using estrogen receptor subtype specific transactivation assays in human bone-derived U2OS cells. Cytotoxicity was measured by using MTT assay in U2OS cells. Overall, we identified two of the herbal extracts (RH, TS) with high and one (AC) with moderate Estrogenic activities, three (BO, PS, HS) with moderate anti-Estrogenic Properties. One extract (GM) showed preferential estrogen receptor subtype specific anti-Estrogenic Properties. A strong cytotoxicity was detected for one extract (XA). With this study on the Estrogenic Properties of plants of tropical origin, we provide evidence for agonistic activity of three plant extracts and antagonistic Properties in four cases which support the traditional use for gynecological or reproductive purposes of some investigated plants. In order to prevent intoxications of the local population the observed cytotoxic extract has to be investigated in detail. Acknowledgements: We thank Dr. Thea Lautenschlager and Prof. Christoph Neinhuis in collaboration with their partners in Angola for collecting and providing the plant material.
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Oleocanthal Modulates Estradiol-Induced Gene Expression Involving Estrogen Receptor α.
Planta Medica, 2015Co-Authors: Annekathrin Martina Keiler, Sefirin Djiogue, Tino Ehrhardt, Oliver Zierau, Leandros Skaltsounis, Maria Halabalaki, Günter VollmerAbstract:Oleocanthal is a bioactive compound from olive oil. It has attracted considerable attention as it is anti-inflammatory, antiproliferative, and has been shown to possess neuroprotective Properties in vitro and in vivo. Delineated from its polyphenolic structure, the aim of this study was to characterize oleocanthal towards Estrogenic Properties. This might contribute to partly explain the beneficial effects described for the Mediterranean diet. Estrogenic Properties of oleocanthal were assessed by different methods: a) stimulation of reporter gene activity in MVLN or RNDA cells either expressing estrogen receptor α or β, b) stimulation of luciferase reporter gene activity in U2OS osteosarcoma cells expressing estrogen receptor α or β, and c) elucidation of the impact on estradiol-induced gene expression in U2OS cells transduced with both estrogen receptors. Depending on the cell line origin, oleocanthal inhibited luciferase activity (MVLN, U2OS-estrogen receptor β) or weakly induced reporter gene activity at 10 µM in U2OS-estrogen receptor α cells. However, oleocanthal inhibited stimulation of luciferase activity by estradiol from both estrogen receptors. Oleocanthal, if given alone, did not stimulate gene expression in U2OS cells, but it significantly modulated the response of estradiol. Oleocanthal enhanced the effect of estradiol on the regulation of those genes, which are believed to be regulated through heterodimeric estrogen receptors. As the Estrogenic response pattern of oleocanthal is rather unique, we compared the results obtained with oleacein. Oleocanthal binds to both estrogen receptors inducing estradiol-agonistic or antiagonistic effects depending on the cell line. Regarding regulation of gene expression in U2OS-estrogen receptor α/β cells, oleocanthal and oleacein enhanced estradiol-mediated regulation of heterodimer-regulated genes.
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Estrogenic Properties of naturally occurring prenylated isoflavones in U2OS human osteosarcoma cells: Structure-activity relationships.
The Journal of steroid biochemistry and molecular biology, 2010Co-Authors: Sefirin Djiogue, Maria Halabalaki, Dieudonné Njamen, Georg Kretzschmar, Antje Beyer, Jean-claude Mbanya, Alexios-leandros Skaltsounis, Günter VollmerAbstract:Eight isoflavones derivatives, with isoprenyl and/or 7-methoxy substitution, isolated from Erythrina poeppigiana (Fabaceae) have been investigated for their Estrogenic Properties in receptor subtype-specific reporter gene assays. First we focused on their estrogen receptor alpha and beta (ERalpha and ERbeta) selectivity, second we addressed structure-activity relationships, using bone-derived human osteosarcoma cell line (U2OS cells) stably expressing ERalpha or transiently expressing ERbeta. Our results show that a substitution at position 3' together with a 7-methoxy substitution on the genistein skeleton is associated with a statistically significant activation of the ERalpha- and ERbeta-dependent reporter gene expression in U2OS cells starting from 0.1nM. Particularly, the 7-methoxy-3'-isoprenyl (1) and the 7-methoxy-3'-(3-methyl-2-hydroxybuten-3-yl) (3) derivatives of genistein induces an ERalpha- and ERbeta-coupled luciferase activity at a concentration ten times lower than that of genistein, for which a statistically significant effect was observable at 1nM. On the other hand, isoprenyl substitution at position 6 of the A ring, compound 5, seems to have very little impact on the genistein ability to induce ER-coupled luciferase activity in U2OS cells, while a double prenylation at positions 8 and 3', compound 7, is associated with an almost complete loss of function on the reporter gene activation in U2OS-ERalpha, but in ERbeta expressing system the effectiveness remains on a statistically significant level, demonstrating an "exclusive ERbeta-selectivity" in U2OS human osteosarcoma cells, and therefore 7 can be considered as an isotype-selective ER ligand. Finally all the tested isoflavones derivatives appear to exhibit a slightly pronounced ERbeta preference, depending upon the position and the nature of the substituent moiety on the isoflavone skeleton. The estrogen-like effect of these prenylated isoflavone derivatives could be inhibited by the pure ER antagonist ICI 182 780, indicating that these effects were primarily mediated through ERs.
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Estrogenic Properties of isoflavones derived from Millettia griffoniana.
Phytomedicine : international journal of phytotherapy and phytopharmacology, 2005Co-Authors: G. J. M. Ketcha Wanda, Oliver Zierau, Dieudonné Njamen, Emmanuel Yankep, M. Tagatsing Fotsing, Z. Tanee Fomum, Jannette Wober, S. Starcke, Günter VollmerAbstract:Abstract In most developing countries, 70–80% of the population still resort to traditional medicine for their primary health care. This medicine utilises medicinal plants which are traditionally taken as concoction and infusion. The root and stem bark of Millettia griffoniana (Leguminosae), has been reported to contain isoflavonoids, alkaloids, and diterpenoids. The possible benefit of some bioactive isoflavones derived from M. griffoniana prompted us to screen them for Estrogenic activity. Six isoflavones and coumarin derived from M. griffoniana (bail) namely, compound nos. 1–6 (Fig. 1) were tested for their potential Estrogenic activities in three different estrogen receptor alpha (ERα)-dependent assays. In a yeast-based ERα assay, all test substances and 17β-estradiol as endogenous agonist, showed a significant induction of β-galactosidase activity. The test compounds at the concentration of 5×10−6 M could achieve 59–121% of the β-galactosidase induction obtained with 10−8 M 17β-estradiol (100%). In the reporter gene assay based on stably transfected MCF-7 cells (MVLN cells), the estrogen responsive induction of luciferase was also stimulated by the M. griffoniana isoflavones. In Ishikawa cells, all substances exhibited Estrogenic activity revealed by the induction of alkaline phosphatase (AlkP) activity. The Estrogenic activities of isoflavones from M. griffoniana could be completely suppressed by the pure estrogen antagonist, ICI 182,780, suggesting that the compounds exert their activities through ERα. Although all substances showed Estrogenic effects, 4′-methoxy-7-O-[(E)-3-methyl-7-hydroxymethyl-2,6-octadienyl]isoflavone (7-O-DHF), Griffonianone C (GRIF-C), and 3’,4’-dihydroxy-7-O-[(E)-3,7-dimethyl-2,6-octadienyl]isoflavone (7-O-GISO) were found to be the most potent of tested substances. In summary, Estrogenic activities of the isoflavones derived from M. griffoniana were described for the first time using reporter gene assays and the estrogen-inducible AlkP Ishikawa model.
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AntiEstrogenic activities of Cimicifuga racemosa extracts.
The Journal of steroid biochemistry and molecular biology, 2002Co-Authors: Oliver Zierau, Claudia Bodinet, Susanne Kolba, Marina Wulf, Günter VollmerAbstract:Despite the wide use of extracts from the rhizome of black cohosh (Cimicifuga racemosa) for the treatment of menopausal complaints, surprisingly little is known on their potential Estrogenic Properties, e.g. on estrogen dependent gene transcription. In addition, available informations on the effects on cell proliferation are contradictory. We therefore, tested for Estrogenic and antiEstrogenic effects of Cimicifuga racemosa extracts on proliferation of MCF-7 cells and on gene expression using ethanolic and iso-propanolic extracts of this medical plant. Estrogenic Properties of plant extracts could neither be detected in proliferation assays, nor on gene expression using an estradiol-inducible yeast assay or the estrogen-inducible MVLN cells. In contrast, in all three experimental systems Cimicifuga racemosa antagonized estradiol induced activities. Estradiol induced stimulation of proliferation was inhibited by a dosage >1 microg/ml of extract concentration, gene expression was suppressed by doses of 100-1000 microg/ml of Cimicifuga racemosa extracts. From these results we conclude, that extracts from the rhizome of Cimicifuga racemosa contain compounds with antiEstrogenic Properties.
Stéphane Zingue - One of the best experts on this subject based on the ideXlab platform.
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Ethanol-extracted Cameroonian propolis exerts Estrogenic effects and alleviates hot flushes in ovariectomized Wistar rats
BMC Complementary and Alternative Medicine, 2017Co-Authors: Stéphane Zingue, Thomas Michel, Derek Tantoh Ndinteh, Jules Tchatchou, Moïse Adamou, Xavier Fernandez, Fernand-nestor Tchuenguem Fohouo, Colin Clyne, Dieudonné NjamenAbstract:Background Since the biological Properties of propolis depend to the plants that can be found in a specific region, propolis from unexplored regions attracts the attention of scientists. Ethanolic extract of Cameroonian propolis (EEP) is used to treat various ailments including gynecological problems and amenorrhea. Since there were no scientific data to support the above claims, the present study was therefore undertaken to assess Estrogenic Properties of Cameroonian propolis. Methods To achieve our goal, the ability of EEP to induce MCF-7 cells proliferation in E-screen assay as well as to activate estrogen receptors α (ERα) and β (ERβ) in cell-based reporter gene assays using human embryonic kidney cells (HEK293T) transfected with ERs was tested. Further, a 3-day uterotrophic assay was performed and the ability of EEP to alleviate hot flushes in ovariectomized adult rats was evaluated. Results In vitro, EEP showed an antiEstrogenic activity in both HEK293T ER-α and ER-β cells. In vivo, EEP induced a significant increase in a bell shape dose response manner of the uterine wet weight, the total protein levels in the uterus, the uterine and vaginal epithelium height and acini border cells of mammary gland with the presence of abundant eosinophil secretions. Moreover, EEP induced a significant decrease in the total number, average duration as well as frequency of hot flushes after 3 days of treatment in rat (equivalent to a month in woman). The dose of 150 mg/kg exhibited the most potent Estrogenic effects among all the tested doses. The UPLC-HRMS analysis showed the presence of caffeic acid derivatives and trirtepernoids in EEP, which are well known endowed with Estrogenic Properties. Conclusion These results suggest that Ethanolic extract of Cameroonian propolis has estrogen-like effects in vivo and may alleviate some menopausal problems such as vaginal dryness and hot flushes. Graphical abstract Ethanol-extracted Cameroobian propolis exhibited in vitro and in vivo estrogen-like effects. This extract may contain promising phytoestrogens.
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Estrogenic Properties of spices of the traditional Cameroonian dish "Nkui" in ovariectomized Wistar rats.
Journal of complementary & integrative medicine, 2016Co-Authors: Edwige Nana Tchoupang, Sylvin Benjamin Ateba, Stéphane Zingue, Martin Zehl, Liselotte Krenn, Dieudonné NjamenAbstract:BACKGROUND Besides the basic role to flavor and color foods, several health benefits have been attributed to spices. The traditional Cameroonian food "Nkui" is prepared using several spices (Afrostyrax lepidophyllus Mildbr., Capsicum frutescens Linn., Fagara leprieurii Guill. et Perr., Fagara tessmannii Engl., Mondia whitei Hook. F. Skell., Pentadiplandra brazzeana Baill., Solanum gilo Raddi., Tetrapleura tetraptera Taub. and Xylopia parviflora A. Rich. Benthane) that are believed to have a positive impact on the female reproductive physiology. Aiming to determine the potential effect of this food on the female reproductive tract, we evaluated the Estrogenic Properties of aqueous and ethanol extracts of Nkui using a 3-day uterotrophic assay in ovariectomized (OVX) rats. METHODS OVX female Wistar rats were randomly separated in several groups of five animals each and submitted to a 3-day uterotrophic assay (per os). At the end of treatment, animals were sacrificed and uterus, vagina and mammary gland collected and fixed in 10 % formalin for histological analysis. RESULTS These extracts increased the uterine wet weight, the uterine and vaginal epithelial heights, and the lumen and diameter of alveoli in the mammary glands. They also altered the estradiol-induced increase of uterine wet weight. The dichloromethane and methanol fractions of the ethanol extract exhibited Estrogenic Properties as well by increasing uterine and vaginal endpoints. CONCLUSIONS These results suggest that the spices of "Nkui" contain Estrogenic phytoconstituents and this traditional food may be considered as functional.
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The methanol-soluble fraction of Millettia macrophylla (Fabaceae) stem bark endowed with Estrogenic Properties has adverse effects on the male reproductive system of Wistar rats
Journal of basic and clinical physiology and pharmacology, 2015Co-Authors: Stéphane Zingue, Chantal Beatrice Magne Nde, Dieudonné NjamenAbstract:BACKGROUND The use of traditional medicinal plants to treat various diseases is common in Sub-Saharan African countries, including Cameroon. Millettia macrophylla, one of such plants, was previously found to exhibit Estrogenic Properties in female Wistar rats. However, its effects on the male reproductive system are unknown. Based on literature evidence that phytoestrogens impair male sexual behavior, we aimed at assessing the effect of the extracts of M. macrophylla stem bark on the male reproductive system of Wistar rats. MATERIALS AND METHODS We evaluated the effects of the dichloromethane (DCM) and methanol (MeOH) soluble fractions of M. macrophylla stem bark on male rat sexual behavior, as well as androgen-dependent parameters for 60 days. RESULTS Data showed a significant decrease (p
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the methanol soluble fraction of millettia macrophylla fabaceae stem bark endowed with Estrogenic Properties has adverse effects on the male reproductive system of wistar rats
Journal of basic and clinical physiology and pharmacology, 2015Co-Authors: Stéphane Zingue, Chantal Beatrice Magne Nde, Dieudonné NjamenAbstract:BACKGROUND The use of traditional medicinal plants to treat various diseases is common in Sub-Saharan African countries, including Cameroon. Millettia macrophylla, one of such plants, was previously found to exhibit Estrogenic Properties in female Wistar rats. However, its effects on the male reproductive system are unknown. Based on literature evidence that phytoestrogens impair male sexual behavior, we aimed at assessing the effect of the extracts of M. macrophylla stem bark on the male reproductive system of Wistar rats. MATERIALS AND METHODS We evaluated the effects of the dichloromethane (DCM) and methanol (MeOH) soluble fractions of M. macrophylla stem bark on male rat sexual behavior, as well as androgen-dependent parameters for 60 days. RESULTS Data showed a significant decrease (p<0.05) in the wiring-touch frequency, mount frequency, intromission frequency, ejaculatory frequency, penile-licking frequency, and computed indices of sexual behavior, throughout the experimental period, as well as a significant increase (p<0.001) in mount, intromission, and ejaculatory latencies as well as post-ejaculatory interval. Moreover, we observed a significant decrease (p<0.05) in the androgen-dependent sexual parameters evaluated. The DCM extract did not induce significant effects on the assessed parameters. CONCLUSIONS These results suggest that long-term exposure to the Estrogenic MeOH fraction of M. macrophylla stem bark negatively alters sexual behavior and spermatogenesis.
Hermann Ulbricht - One of the best experts on this subject based on the ideXlab platform.
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A novel type of nonsteroidal estrone sulfatase inhibitors.
Bioorganic & medicinal chemistry letters, 2002Co-Authors: Peter Jütten, Winfried Schumann, Albert Härtl, Lothar Heinisch, Udo Gräfe, Walter Werner, Hermann UlbrichtAbstract:Abstract Madurahydroxylactone (MHL) is a secondary metabolite produced by the soil bacterium Nonomuria rubra and belongs to the family of benzo[ a ]naphthacenequinones. We report the initial results and structure–activity relationships of our study into a series of thiosemicarbazone derivatives of madurahydroxylactone as potential nonsteroidal inhibitors of the enzyme estrone sulfatase. The most active compound, the cyclohexylthiosemicarbazone, was shown to be a non-competitive inhibitor with a K i of 0.35 μM. This compound is devoid of Estrogenic Properties and showed low acute toxicity in the hen's fertile egg screening test.
Oliver Zierau - One of the best experts on this subject based on the ideXlab platform.
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Oleocanthal Modulates Estradiol-Induced Gene Expression Involving Estrogen Receptor α.
Planta Medica, 2015Co-Authors: Annekathrin Martina Keiler, Sefirin Djiogue, Tino Ehrhardt, Oliver Zierau, Leandros Skaltsounis, Maria Halabalaki, Günter VollmerAbstract:Oleocanthal is a bioactive compound from olive oil. It has attracted considerable attention as it is anti-inflammatory, antiproliferative, and has been shown to possess neuroprotective Properties in vitro and in vivo. Delineated from its polyphenolic structure, the aim of this study was to characterize oleocanthal towards Estrogenic Properties. This might contribute to partly explain the beneficial effects described for the Mediterranean diet. Estrogenic Properties of oleocanthal were assessed by different methods: a) stimulation of reporter gene activity in MVLN or RNDA cells either expressing estrogen receptor α or β, b) stimulation of luciferase reporter gene activity in U2OS osteosarcoma cells expressing estrogen receptor α or β, and c) elucidation of the impact on estradiol-induced gene expression in U2OS cells transduced with both estrogen receptors. Depending on the cell line origin, oleocanthal inhibited luciferase activity (MVLN, U2OS-estrogen receptor β) or weakly induced reporter gene activity at 10 µM in U2OS-estrogen receptor α cells. However, oleocanthal inhibited stimulation of luciferase activity by estradiol from both estrogen receptors. Oleocanthal, if given alone, did not stimulate gene expression in U2OS cells, but it significantly modulated the response of estradiol. Oleocanthal enhanced the effect of estradiol on the regulation of those genes, which are believed to be regulated through heterodimeric estrogen receptors. As the Estrogenic response pattern of oleocanthal is rather unique, we compared the results obtained with oleacein. Oleocanthal binds to both estrogen receptors inducing estradiol-agonistic or antiagonistic effects depending on the cell line. Regarding regulation of gene expression in U2OS-estrogen receptor α/β cells, oleocanthal and oleacein enhanced estradiol-mediated regulation of heterodimer-regulated genes.
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Functions of Danggui Buxue Tang, a Chinese Herbal Decoction Containing Astragali Radix and Angelicae Sinensis Radix, in Uterus and Liver are Both Estrogen Receptor-Dependent and -Independent
Evidence-based complementary and alternative medicine : eCAM, 2014Co-Authors: Oliver Zierau, Karl Wah Keung Tsim, Ken Yu-zhong Zheng, Anja Papke, Tina T. X. Dong, G. VollmerAbstract:Danggui Buxue Tang (DBT), a herbal decoction containing Astragali Radix (AR) and Angelicae Sinensis Radix (ASR), has been used in treating menopausal irregularity in women for more than 800 years in China. Pharmacological results showed that DBT exhibited significant Estrogenic Properties in vitro, which therefore suggested that DBT could activate the nuclear estrogen receptors. Here, we assessed the Estrogenic Properties of DBT in an ovariectomized in vivo rat model: DBT was applied to the ovariectomized rats for 3 days. The application of DBT did not alter the weight of uterus and liver, as well as the transcript expression of the proliferation markers including the estrogen receptors α and β. However, DBT stimulated the transcript expression of the estrogen responsive genes. In addition, the inductive role of DBT on the expression of members of the aryl hydrocarbon receptor family in uterus and liver of ovariectomized rats was confirmed. These responses of DBT however were clearly distinct from the response pattern detectable here for 17β-estradiol. Therefore, DBT exhibited weak, but significant, Estrogenic Properties in vivo; however, some of its activities were independent of the estrogen receptor. Thus, DBT could be an exciting Chinese herbal decoction for an alternative treatment of hormone replacement therapy for women in menopause without subsequent Estrogenic side effects.
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Estrogenic Properties of isoflavones derived from Millettia griffoniana.
Phytomedicine : international journal of phytotherapy and phytopharmacology, 2005Co-Authors: G. J. M. Ketcha Wanda, Oliver Zierau, Dieudonné Njamen, Emmanuel Yankep, M. Tagatsing Fotsing, Z. Tanee Fomum, Jannette Wober, S. Starcke, Günter VollmerAbstract:Abstract In most developing countries, 70–80% of the population still resort to traditional medicine for their primary health care. This medicine utilises medicinal plants which are traditionally taken as concoction and infusion. The root and stem bark of Millettia griffoniana (Leguminosae), has been reported to contain isoflavonoids, alkaloids, and diterpenoids. The possible benefit of some bioactive isoflavones derived from M. griffoniana prompted us to screen them for Estrogenic activity. Six isoflavones and coumarin derived from M. griffoniana (bail) namely, compound nos. 1–6 (Fig. 1) were tested for their potential Estrogenic activities in three different estrogen receptor alpha (ERα)-dependent assays. In a yeast-based ERα assay, all test substances and 17β-estradiol as endogenous agonist, showed a significant induction of β-galactosidase activity. The test compounds at the concentration of 5×10−6 M could achieve 59–121% of the β-galactosidase induction obtained with 10−8 M 17β-estradiol (100%). In the reporter gene assay based on stably transfected MCF-7 cells (MVLN cells), the estrogen responsive induction of luciferase was also stimulated by the M. griffoniana isoflavones. In Ishikawa cells, all substances exhibited Estrogenic activity revealed by the induction of alkaline phosphatase (AlkP) activity. The Estrogenic activities of isoflavones from M. griffoniana could be completely suppressed by the pure estrogen antagonist, ICI 182,780, suggesting that the compounds exert their activities through ERα. Although all substances showed Estrogenic effects, 4′-methoxy-7-O-[(E)-3-methyl-7-hydroxymethyl-2,6-octadienyl]isoflavone (7-O-DHF), Griffonianone C (GRIF-C), and 3’,4’-dihydroxy-7-O-[(E)-3,7-dimethyl-2,6-octadienyl]isoflavone (7-O-GISO) were found to be the most potent of tested substances. In summary, Estrogenic activities of the isoflavones derived from M. griffoniana were described for the first time using reporter gene assays and the estrogen-inducible AlkP Ishikawa model.
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AntiEstrogenic activities of Cimicifuga racemosa extracts.
The Journal of steroid biochemistry and molecular biology, 2002Co-Authors: Oliver Zierau, Claudia Bodinet, Susanne Kolba, Marina Wulf, Günter VollmerAbstract:Despite the wide use of extracts from the rhizome of black cohosh (Cimicifuga racemosa) for the treatment of menopausal complaints, surprisingly little is known on their potential Estrogenic Properties, e.g. on estrogen dependent gene transcription. In addition, available informations on the effects on cell proliferation are contradictory. We therefore, tested for Estrogenic and antiEstrogenic effects of Cimicifuga racemosa extracts on proliferation of MCF-7 cells and on gene expression using ethanolic and iso-propanolic extracts of this medical plant. Estrogenic Properties of plant extracts could neither be detected in proliferation assays, nor on gene expression using an estradiol-inducible yeast assay or the estrogen-inducible MVLN cells. In contrast, in all three experimental systems Cimicifuga racemosa antagonized estradiol induced activities. Estradiol induced stimulation of proliferation was inhibited by a dosage >1 microg/ml of extract concentration, gene expression was suppressed by doses of 100-1000 microg/ml of Cimicifuga racemosa extracts. From these results we conclude, that extracts from the rhizome of Cimicifuga racemosa contain compounds with antiEstrogenic Properties.