RESUMO
In multiple sclerosis (MS), demyelination occurs in the cerebral cortex, and cerebral cortex atrophy correlates with clinical disabilities. Treatments are needed in MS to induce remyelination. Pregnancy is protective in MS. Estriol is made by the fetoplacental unit, and maternal serum estriol levels temporally align with fetal myelination. Here, we determined the effect of estriol treatment on the cerebral cortex in the preclinical model of MS, experimental autoimmune encephalomyelitis (EAE). Estriol treatment initiated after disease onset decreased cerebral cortex atrophy. Neuropathology of the cerebral cortex showed increased cholesterol synthesis proteins in oligodendrocytes, more newly formed remyelinating oligodendrocytes, and increased myelin in estriol-treated EAE mice. Estriol treatment also decreased the loss of cortical layer V pyramidal neurons and their apical dendrites and preserved synapses. Together, estriol treatment after EAE onset reduced atrophy and was neuroprotective in the cerebral cortex.
Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Doenças Neurodegenerativas , Gravidez , Feminino , Camundongos , Animais , Neuroproteção , Encefalomielite Autoimune Experimental/tratamento farmacológico , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Estriol/farmacologia , Estriol/uso terapêutico , Córtex Cerebral/metabolismo , Atrofia/tratamento farmacológico , Atrofia/patologia , Camundongos Endogâmicos C57BLRESUMO
Cell-based bioassays are very sensitive and allow integrative effect screening of the whole environmental sample, which is usually composed of a mixture of agonists and antagonists. Measured toxicity is usually expressed as a bioanalytical equivalent concentration. So far, it is not possible to distinguish which part of this value is caused by the agonists and which by the antagonists. In this article, we present a simple method to analyze the dose-response curve of a mixture and to determine an agonistic bioanalytical equivalent concentration: a concentration of a reference chemical that would elicit the same effect as do only agonists in an unknown mixture. The method has been validated using several artificially prepared mixtures of agonists and competitive antagonists measured in a recombinant yeast assay. No difference was observed between the calculated equivalent concentrations and the used concentrations of the agonist in the mixture.
Assuntos
Bioensaio/métodos , Disruptores Endócrinos , Poluentes Ambientais/toxicidade , Interações Medicamentosas , Estradiol/farmacologia , Estriol/farmacologia , Fulvestranto/farmacologia , Modelos Teóricos , Receptores de Estrogênio/antagonistas & inibidores , Saccharomyces cerevisiae/efeitos dos fármacosRESUMO
PURPOSE: To evaluate the pharmacokinetics and pharmacodynamics of oestriol (E3) and trimegestone (TMG) in healthy women after application of three different vaginal rings over 21 days. The vaginal rings had a nominal delivery rate of 0.413/0.050 mg/day (Test 1), 0.311/0.090 mg/day (Test 2) and 0.209/0.137 mg/day (Test 3) E3/TMG. METHODS: Thirty-five healthy women were randomised to receive a single application of Test 1, 2 or 3 (Clinical Trial NCT03343912). The E3 and TMG plasma concentration was determined by LC-MS/MS. Oestradiol (E2) and progesterone (PG) serum concentrations, and bleeding patern were determined as pharmacodynamic parameters. Safety was assessed by evaluation of adverse events and local tolerability. RESULTS: The total and maximum exposure of E3 and TMG increased in a proportional ratio to dose. However, not in a magnitude which was expected from the dose differences for E3. During Test 2 and 3 treatment all E2 and PG values remained on a well suppressed level until end of treatment. E2 and PG serum levels increased distinctly earlier after ring removal with Test 1 compared to Test 2 and 3. Test 3 achieved 95.24% of "no bleeding" days under treatment followed by Test 1 (91.67%), and Test 2 (86.15%). CONCLUSIONS: The Test 3 formulation presented the best dose combination of E3/TMG for contraception. Moreover, all vaginal rings were well tolerated.
Assuntos
Anticoncepcionais Femininos/administração & dosagem , Dispositivos Anticoncepcionais Femininos , Estriol/farmacologia , Estriol/farmacocinética , Estrogênios/metabolismo , Promegestona/análogos & derivados , Administração Intravaginal , Adulto , Cromatografia Líquida , Estradiol/sangue , Estrogênios/sangue , Feminino , Humanos , Progesterona/sangue , Promegestona/farmacocinética , Promegestona/farmacologia , Espectrometria de Massas em TandemRESUMO
The effect of pregnancy hormone estriol (E3) on innate and adaptive immunity cells functions in patients with multiple sclerosis (MS) in comparison with healthy donors (HD) was studied. E3 inhibited phagocytic activity of neutrophils and enhanced monocytes IDO activity. Treg percentage increased and number of Th17 and iNKT cells decreased under E3 influence. At the same time, E3 stimulated production of IL-10 and inhibited secretion of IL-17. The hormonal effects were realized on the cells of both HD and MS patients. Thus, the MS amelioration during pregnancy may be related to E3 influence.
Assuntos
Imunidade Adaptativa/imunologia , Estriol/farmacologia , Imunidade Celular/imunologia , Imunidade Inata/imunologia , Esclerose Múltipla/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Adulto , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Humanos , Imunidade Celular/efeitos dos fármacos , Imunidade Inata/efeitos dos fármacos , Masculino , Esclerose Múltipla/sangueRESUMO
The current study aimed to identify putative drug targets of multidrug resistant Acinetobacter baumannii (MDRAb) and study the therapeutic potential of natural epiestriol-16 by computer aided virtual screening and in vitro studies. The clinical isolates (n = 5) showed extreme dug resistance to carbapenems and colistins (p ≤ .05). Computational screening suggested that out of 236 natural molecules selected, 06 leads were qualified for drug likeliness, pharmacokinetic features and one potential molecule namely natural epiestriol-16 (16b-Hydroxy-17a-estradiol) exhibited significant binding potential towards four prioritised drug targets in comparison with the binding of faropenem to their usual target. Natural epiestriol demonstrated profound binding to the outer membrane protein (Omp38), protein RecA (RecA), orotate phosphoribosyltransferase (PyrE) and orotidine 5'-phosphate decarboxylase (PyrF) with binding energy of -6.0, -7.3, -7.3 and -8.0 kcal/mol respectively. MD simulations suggested that 16-epiestriol-receptor complexes demonstrated stability throughout the simulation. The growth curve and time kill assays revealed that MDRAb showed resistance to faropenem and polymyxin-B and the pure epiestriol-16 showed significant inhibitory properties at a concentration of 200 µg/mL (p ≤ .5). Thus, natural epiestriol-16 can be used as potential inhibitor against the prioritised targets of MDRAb and this study provide insight for drug development against carbapenem and colistin resistant A. baumannii.
Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Proteínas de Bactérias/química , Farmacorresistência Bacteriana Múltipla/genética , Estriol/farmacologia , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/química , Antibacterianos/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Simulação por Computador , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Estriol/química , Estriol/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Terapia de Alvo Molecular , Recombinases Rec A/química , Recombinases Rec A/metabolismoRESUMO
OBJECTIVES: To investigate the effect of androgens and estrogens on surtuin 1 (SIRT1) expression in human aortic endothelial cells (HAECs). METHODS: Real-time polymerase chain reaction analysis of SIRT-1 expression over 48 hours (h) was performed in HAECs treated with various concentrations of dehydroepiandrostendione (DHEA), androstenedione and testosterone (androgens), estrone (E1), estradiol (E2), and estriol (E3) (estrogens) to investigate the dose-dependency of time courses. The influence of high glucose on SIRT1 expression induced by the androgens and estrogens was also examined. RESULTS: Dehydroepiandrostendione, androstenedione, and testosterone remarkedly produced a dose-dependent increase in SIRT1 expression in the range of 10 to 20 µg/ml. High glucose (40mM) medium had significantly inhibitory effects on 10 µg/ml DHEA-induced SIRT1 expression (p=0.024). Estrone and E2, but not E3, caused a marked dose-dependent increase in SIRT1 expression from 10 to 20 µg/ml. Treatment with 20 mM or 40 mM glucose medium did not significantly inhibit E1- and E3-induced SIRT1 expression in control medium; however, both high glucose mediums significantly emphasized E2-induced SIRT1 expression in control medium (p=0.007, p=0.005). CONCLUSION: These results suggest that DHEA, androstenedione, testosterone, E1, and E2 definitely activate SIRT1 expression in HAECs. A high glucose medium is potent to inhibit the basal gene expression; however, it could not reduce powerful androgen- and estrogen-induced SIRT1 expression in HAECs.
Assuntos
Androgênios/farmacologia , Aorta/citologia , Células Endoteliais/metabolismo , Estrogênios/farmacologia , Expressão Gênica/efeitos dos fármacos , Sirtuína 1/genética , Sirtuína 1/metabolismo , Androstenodiona/farmacologia , Células Cultivadas , Desidroepiandrosterona/farmacologia , Relação Dose-Resposta a Droga , Estradiol/farmacologia , Estriol/farmacologia , Estrona/farmacologia , Glucose/farmacologia , Humanos , Reação em Cadeia da Polimerase em Tempo Real , Testosterona/farmacologiaRESUMO
In ovariohysterectomized dogs, the uterine stump rarely causes clinical disease. However, changes could occur in this anatomic structure due to exposure to estrogen therapy. Ultrasonographic examination of the uterine stump has not been reported in dogs receiving estriol and normal dimensions for this area have not been reported for ovariohysterectomized dogs. Therefore, the aims of this study were to retrospectively evaluate records and ultrasound images from dogs receiving and not receiving (controls) estriol as well as defining a standard method to measure the uterine stump. Clinical features of dogs administered estriol were also reported. Fourteen dogs receiving estriol and 14 control dogs were included in the study. Seven dogs receiving estriol had changes associated with the external vulva, 5 were noted to be "hooded" and 3 were "prominent/swollen." Ultrasonographic transverse maximum uterine stump measurements were available for 4 dogs receiving estriol (median 0.81 cm, range 0.53-1.4). The maximum uterine height/aorta ratio was available for only 2 dogs receiving estriol (0.9 and 0.6). The median transverse maximum height of the uterine stump noted in the control group was 0.43 cm (range 0.28-0.52 cm); The maximal uterine height/aorta ratio was a median of 0.48 in the control group (range 0.32-1.1). Normal values for the uterine stump measurements can be standardized to the distal aorta for consistency. Vulvar enlargement was the most common physical examination change in our dogs receiving estriol. Routine screening, including ultrasonography is not usually indicated for dogs receiving estriol, but can be tailored to the individual patient.
Assuntos
Estriol/farmacologia , Histerectomia/veterinária , Ovariectomia/veterinária , Útero/efeitos dos fármacos , Animais , Doenças do Cão/tratamento farmacológico , Cães , Estriol/administração & dosagem , Feminino , Estudos Retrospectivos , Ultrassonografia/veterinária , Incontinência Urinária/tratamento farmacológico , Incontinência Urinária/veterinária , Útero/diagnóstico por imagem , Útero/cirurgiaRESUMO
PROBLEM: Indoleamine 2,3-dioxygenase (IDO) is a key protein that participates in the protection of embryos against the mother's immune system during pregnancy. How the expression of this protein is regulated at the maternal-fetal interface remains largely unknown. METHOD OF STUDY: The chorionic villi and decidua of women in early pregnancy were collected. Tissue explants of the chorionic villi and decidua were cultured in media containing varying concentrations of 17ß-estradiol and estriol with or without fulvestrant. Western blot analysis and quantitative reverse transcription-polymerase chain reaction (qRT-PCR) were used to detect the expression of IDO and the suppressors of cytokine signaling 3 (SOCS3) in the cultured tissues from chorionic villi and decidua. RESULTS: Both IDO and SOCS3 were expressed in chorionic villi and decidua. The expression of IDO was increased in tissue explants from chorionic villi and decidua cultured in medium containing different concentrations of 17ß-estradiol or estriol, and this increase was reversed when fulvestrant was added to the medium. The expression of IDO was upregulated, and SOCS3 expression was downregulated the most in tissue explants from chorionic villi and decidua that were cultured in medium containing 17ß-estradiol at a concentration of 10 ng/mL or estriol at a concentration of 1 µg/mL. This increase in IDO and decrease in SOCS3 were reversed when fulvestrant was added to the medium at a concentration of 10 µg/mL. CONCLUSION: At a concentration similar to that present during pregnancy, estrogen may upregulate the expression of IDO via downregulating SOCS3, which implies that estrogen may contribute to the prevention of allogeneic fetal rejection, and further studies may strengthen the possibility of using estrogen as an immune modulator.
Assuntos
Vilosidades Coriônicas/efeitos dos fármacos , Decídua/efeitos dos fármacos , Estradiol/farmacologia , Estriol/farmacologia , Estrogênios/farmacologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Proteína 3 Supressora da Sinalização de Citocinas/metabolismo , Adulto , Vilosidades Coriônicas/metabolismo , Decídua/metabolismo , Feminino , Humanos , Indolamina-Pirrol 2,3,-Dioxigenase/genética , Gravidez , Proteína 3 Supressora da Sinalização de Citocinas/genética , Adulto JovemRESUMO
Estrogen receptor (ER) sequences vary between species and this suggests that there are differences in the ligand-specificity, leading to species-specific effects. This would indicate that it is not possible to generalize effects across species. In this study, we investigated the differences in activation potencies and binding affinities of ER´s alpha (α) and beta (ß) in human, zebrafish and sea bream to elucidate species differences in response to estradiol, estrone, estriol and methyltestosterone. In vitro analysis showed that estradiol had the highest activity for all the ER´s except for human ERß and seabream ERß2. Alignment of the ligand binding domain and ligand binding pocket (LBP) residues of the three species showed that different residues were involved in the LBPs which led to differences in pocket volume, affected binding affinity and orientation of the ligands. By combining in silico and in vitro results, it was possible to identify the ligand specificities of ER´s. The results demonstrated that the human ER´s show lower resolution in ligand-dependent activation, suggesting higher promiscuity, than the zebrafish and seabream ER´s. These results show species-specificity of ER´s and suggest that species-specific differences must be taken into consideration when studying different exposure scenarios.
Assuntos
Androgênios/farmacologia , Estrogênios/farmacologia , Proteínas de Peixes/metabolismo , Receptores de Estrogênio/metabolismo , Animais , Linhagem Celular , Estradiol/farmacologia , Estriol/farmacologia , Estrona/farmacologia , Proteínas de Peixes/genética , Humanos , Ligantes , Metiltestosterona/farmacologia , Simulação de Acoplamento Molecular , Receptores de Estrogênio/genética , Dourada , Especificidade da Espécie , Peixe-ZebraRESUMO
We studied the effect of estriol, chorionic gonadotropin, oncostatin M, and hormone-cytokine combinations on the expression of recombinase RAG-1 in T-regulatory (Treg) and T helper 17 (Th17) lymphocytes. It was found that estriol in a concentration corresponding to the first trimester of pregnancy increased the level of Treg (CD4+FoxP3+) cells and suppressed the formation of Th17 (CD4+RORC+) lymphocytes. This effect was nor observed after individual administration of chorionic gonadotropin and oncostatin M, but some combinations of the studied hormones with oncostatin M increased the percentage of CD4+FOXP3+ cells. In the presence of oncostatin M, the studied hormones enhanced the expression of RAG-1 in CD4+FoxP3+ cells, but not in CD4+RORC+ cells, thereby initiating of Treg T-cell receptor (TCR) revision. The mechanisms of hormone cytokine control of induction of the immune tolerance during pregnancy are discussed.
Assuntos
Gonadotropina Coriônica/farmacologia , Estriol/farmacologia , Oncostatina M/farmacologia , Recombinases/metabolismo , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/enzimologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Células Cultivadas , Feminino , Fatores de Transcrição Forkhead/metabolismo , HumanosRESUMO
INTRODUCTION: Progressive gray matter (GM) atrophy is a hallmark of multiple sclerosis (MS). Cognitive impairment has been observed in 40%-70% of MS patients and has been linked to GM atrophy. In a phase 2 trial of estriol treatment in women with relapsing-remitting MS (RRMS), higher estriol levels correlated with greater improvement on the paced auditory serial addition test (PASAT) and imaging revealed sparing of localized GM in estriol-treated compared to placebo-treated patients. To better understand the significance of this GM sparing, the current study explored the relationships between the GM sparing and traditional MRI measures and clinical outcomes. METHODS: Sixty-two estriol- and forty-nine placebo-treated RRMS patients underwent clinical evaluations and brain MRI. Voxel-based morphometry (VBM) was used to evaluate voxelwise GM sparing from high-resolution T1-weighted scans. RESULTS: A region of treatment-induced sparing (TIS) was defined as the areas where GM was spared in estriol- as compared to placebo-treated groups, localized primarily within the frontal and parietal cortices. We observed that TIS volume was directly correlated with improvement on the PASAT. Next, a longitudinal cognitive disability-specific atlas (DSA) was defined by correlating voxelwise GM volumes with PASAT scores, that is, areas where less GM correlated with less improvement in PASAT scores. Finally, overlap between the TIS and the longitudinal cognitive DSA revealed a specific region of cortical GM that was preserved in estriol-treated subjects that was associated with better performance on the PASAT. CONCLUSIONS: Discovery of this region of overlap was biology driven, not based on an a priori structure of interest. It included the medial frontal cortex, an area previously implicated in problem solving and attention. These findings indicate that localized GM sparing during estriol treatment was associated with improvement in cognitive testing, suggesting a clinically relevant, disability-specific biomarker for clinical trials of candidate neuroprotective treatments in MS.
Assuntos
Disfunção Cognitiva/prevenção & controle , Estriol/farmacologia , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/patologia , Neuroproteção/efeitos dos fármacos , Adulto , Atrofia , Disfunção Cognitiva/complicações , Disfunção Cognitiva/patologia , Feminino , Substância Cinzenta/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Testes Neuropsicológicos , Adulto JovemRESUMO
Estriol (E3) is an endogenous estrogen in females with broad biological activity within diverse tissue types. In the context of certain T-cell-mediated autoimmune inflammatory diseases, E3 can ameliorate disease severity through immunomodulatory mechanisms that decrease tissue inflammation. Severe disease caused by influenza A virus (IAV) infection is also characterized by aberrant inflammation and immunopathology. How E3 might affect the pathogenesis of IAV infection, however, has not been explored. Gonadally intact female C57BL/6 mice that were treated with exogenous E3 during infection with mouse-adapted 2009 H1N1 had reduced total pulmonary inflammation and improved disease outcomes compared with females that received no hormone. Furthermore, compared with no hormone treatment, E3 treatment reduced the induction of genes associated with proinflammatory cytokine and chemokine responses in the lungs, which preceded clinical disease, reductions in innate immune cell recruitment, altered pulmonary T-cell skewing, and reduced antibody titers during IAV infection. Although E3 treatment was associated with reduced local and systemic anti-influenza adaptive immune responses, there was no effect of E3 on viral replication or clearance. Together, these data suggest that exogenous E3 confers protection during IAV infection through immunomodulatory mechanisms and that E3 may have broad therapeutic potential in the context of both infectious and noninfectious inflammatory diseases.
Assuntos
Citocinas/efeitos dos fármacos , Estriol/farmacologia , Pulmão/efeitos dos fármacos , Infecções por Orthomyxoviridae/imunologia , Pneumonia Viral/imunologia , Linfócitos T/efeitos dos fármacos , Animais , Quimiocinas/efeitos dos fármacos , Quimiocinas/imunologia , Citocinas/imunologia , Feminino , Inflamação/imunologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Pulmão/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Índice de Gravidade de Doença , Replicação Viral/efeitos dos fármacosRESUMO
We studied the effect of hormones estriol, ghrelin, kisspeptin, and chorionic gonadotropin in concentrations corresponding to their content in the peripheral blood in each trimester of pregnancy on the expression of membrane molecules on myeloid and plasmacytoid dendritic cells of the thymus. It was found that thymic myeloid dendritic cells are sensitive to the action of estriol and kisspeptin. Estriol in a concentration of the first trimester of pregnancy reduces the number of myeloid dendritic cells expressing receptor for thymic stromal lymphopoietin (CD11c+TSLP-R+) and inhibitory molecule B7-H3 (CD11c+CD276+). In contrast to estriol, kisspeptin regulates the processes of differentiation of thymic myeloid dendritic cells in concentrations typical of the second-third trimesters and reduced their total number (CD11c+) and the number of cells expressing TSLP-R (CD11c+TSLP-R+). Estriol and kisspeptin do not affect the total number of plasmacytoid dendritic cells (CD303+) and expression of TSLP-R and CD276 by these cells. Ghrelin and chorionic gonadotropin in the studied concentrations had no significant effect on the total number of thymic myeloid and plasmacytoid dendritic cells and on the expression of membrane molecules of TSLP-R and CD276.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Células Dendríticas/efeitos dos fármacos , Hormônios/farmacologia , Timo/citologia , Células Cultivadas , Gonadotropina Coriônica/sangue , Gonadotropina Coriônica/farmacologia , Células Dendríticas/fisiologia , Estriol/sangue , Estriol/farmacologia , Feminino , Grelina/sangue , Grelina/farmacologia , Hematopoese/efeitos dos fármacos , Hormônios/sangue , Humanos , Lactente , Recém-Nascido , Kisspeptinas/sangue , Kisspeptinas/farmacologia , Troca Materno-Fetal/fisiologia , Gravidez/sangue , Cultura Primária de Células , Timócitos/citologia , Timócitos/efeitos dos fármacos , Timócitos/fisiologia , Timo/efeitos dos fármacosRESUMO
BACKGROUND: An increase in the level of cytokines like TNF-α and IL-6 causes the inflammatory surge in acute ischemic heart disease (AIHD). OBJECTIVE: A high-level dermcidin isoform-2 (DCN-2) occurrence in AIHD was subjected to determine a possible regulation of cytokines expression. The effect of estrogen to counteract the inflammatory response was determined. METHODS: Blood was collected from AIHD patients and normal volunteers with consent. Nitric oxide (NO) synthesis was done with methemoglobin method.TNF-α and IL-6 expression were determined by ELISA and Western blot. RESULTS: (DCN-2) incubation with 120nM to the normal neutrophil solution for 2h resulted in the increase of TNF-α from 3.82±1.53pg/ml to 20.7±6.9pg/ml and IL-6 from 3.27±1.52pg/ml to 47.07±3.4pg/ml. In AIHD patients, the cytokine level was18.3- 27.3pg/ml, with a median value 21.86pg/ml (TNF-α) and IL-6 level was 23.54- 52.73pg/ml, with a median value 42.16pg/ml. Treatment with 0.6nM estriol, a kind of female steroid hormone estrogen for 45min decreased the elevated cytokine level in 120nM DCN-2 treated normal neutrophils. DCN-2 induced TNF-α synthesis in neutrophils was further determined by Western blot technique with a thickened band intensity of TNF-α. Estriol (0.6nM) treatment also influenced the DCN-2 induced inhibition of nitric oxide (NO) synthesis from 0nmol NO/ml to 0.56nmol/ml. The subsequent reduction of TNF-α level correlates the increase of NO level. CONCLUSION: In conclusion, the stress-induced DCN-2 production in AIHD propagates the inflammatory response. Steroid molecule like estriol plays a protective role by reducing DCN-2 responses in the NO synthesis.
Assuntos
Estriol/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-6/biossíntese , Isquemia Miocárdica/metabolismo , Neutrófilos/metabolismo , Óxido Nítrico/biossíntese , Peptídeos/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Adulto , Feminino , Humanos , Masculino , Isquemia Miocárdica/patologia , Neutrófilos/patologia , Isoformas de Proteínas/biossínteseRESUMO
Recent studies demonstrated that G-protein-coupled receptor 30 (GPR30) on the plasma membrane of gonadotroph cells mediates picomolar, but not nanomolar, levels of estradiol (E2) to rapidly suppress gonadotropin-releasing hormone (GnRH)-induced luteinizing hormone (LH) secretion in the anterior pituitary (AP). While estrone (E1) and estriol (E3) are considered "weak" estrogens that exert suppressive effects through estrogen receptors α and ß, it is conceivable that they also strongly suppress GnRH-induced LH secretion via GPR30. Both E1 and E3 are likely present within the blood at picomolar or nanomolar concentrations, indicating that such concentrations are sufficient to suppress GnRH-induced LH secretion. To evaluate this possibility, bovine AP cells were cultured under steroid-free conditions and then incubated with various concentrations (0.01 pM to 10 nM) of E2, E1, or E3, prior to stimulation with GnRH. Notably, GnRH-induced LH secretion from AP cells was inhibited by 1-100 pM E2, 1-10 pM E1, and 1-100 pM E3. GnRH-induced LH secretion from AP cells was not inhibited by lower (0.01-0.1 pM) or higher (1-10 nM) concentrations of E2, E1, and E3. These suppressive effects were inhibited by pre-treatment of AP cells with the GPR30 antagonist G36, but not with the estrogen receptor alpha antagonist. Treatment with E1 or E3 also yielded decreased cytoplasmic cAMP levels in cultured AP cells pre-treated with dopamine and phosphodiesterase inhibitors. Therefore, these results suggest that GPR30 mediates the suppressive effects of E1, E3, and E2 on GnRH-induced LH secretion from bovine AP.
Assuntos
Estradiol/farmacologia , Estriol/farmacologia , Estrona/farmacologia , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Hormônio Luteinizante/metabolismo , Adeno-Hipófise/efeitos dos fármacos , Receptores de Estrogênio/fisiologia , Animais , Bovinos , Células Cultivadas , Estradiol/metabolismo , Estriol/metabolismo , Estrona/metabolismo , Feminino , Hormônio Liberador de Gonadotropina/farmacologia , Adeno-Hipófise/metabolismo , Receptores de Estrogênio/metabolismo , Via Secretória/efeitos dos fármacosRESUMO
Estrogens are potent and efficacious neuroprotectants both in vitro and in vivo in a variety of models of neurotoxicity. We determined the structural requirements for neuroprotection in an in vitro assay using a panel of >70 novel estratrienes, synthesized to reduce or eliminate estrogen receptor (ER) binding. We observed that neuroprotection could be enhanced by as much as 200-fold through modifications that positioned a large bulky group at the C2 or C4 position of the phenolic A ring of the estratriene. Further, substitutions on the B, C or D rings either reduced or did not markedly change neuroprotection. Collectively, there was a negative correlation between binding to ERs and neuroprotection with the more potent compounds showing no ER binding. In an in vivo model for neuroprotection, transient cerebral ischemia, efficacious compounds were active in protection of brain tissue from this pro-oxidant insult. We demonstrated that these non-feminizing estrogens engage in a redox cycle with glutathione, using the hexose monophosphate shunt to apply cytosolic reducing potential to cellular membranes. Together, these results demonstrate that non-feminizing estrogens are neuroprotective and protect brain from the induction of ischemic- and Alzheimer's disease (AD)-like neuropathology in an animal model. These features of non-feminizing estrogens make them attractive compounds for assessment of efficacy in AD and stroke, as they are not expected to show the side effects of chronic estrogen therapy that are mediated by ER actions in the liver, uterus and breast.
Assuntos
Encéfalo/efeitos dos fármacos , Estradiol/farmacologia , Estriol/farmacologia , Estrogênios/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Estradiol/análogos & derivados , Estradiol/química , Estradiol/metabolismo , Estriol/análogos & derivados , Estriol/química , Estriol/metabolismo , Estrogênios/química , Estrogênios/metabolismo , Humanos , Estrutura Molecular , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/metabolismo , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Receptores de Estrogênio/metabolismo , Relação Estrutura-AtividadeRESUMO
The prevalence rate of cardiovascular disease is higher for males than females, and estradiol (E2) induces AMP-activated protein kinase (AMPK) activation, which is known to regulate proliferation of VSMC. We identified the estrogenic properties of nordihydroguaiaretic acid (NDGA, a lignan phytoestrogen) that inhibit VSMC proliferation and explored the underlying mechanisms. Both the phosphorylation and expression of LKB1 were increased by NDGA. In addition, NDGA significantly attenuated angiotensin II (Ang II)-induced VSMC proliferation. To elucidate the estrogenic effects, we confirmed that NDGA increased estrogen receptor α (ERα) expression, similar to treatment with E2 and estriol (E3). Furthermore, tamoxifen and ERα siRNA obstructed the effects of NDGA including ERα expression, AMPK phosphorylation and both LKB1 phosphorylation and expression. VSMC proliferation was restored by tamoxifen and ERα siRNA. LKB1 siRNA also reversed the NDGA-mediated inhibition of VSMC proliferation. The estrogenic activity of NDGA induced LKB1 translocation from nucleus to cytosol, and tamoxifen obstructed LKB1 translocation. The absence of LKB1 completely abolished the increase of ERα expression induced by NDGA. Taken together, the beneficial effects of estrogenic compound (E2 and NDGA) on inhibition of VSMC proliferation are mediated by interaction between LKB1 and ERα, suggesting a potential mechanism for females having less cardiovascular disease.
Assuntos
Estradiol/farmacologia , Receptor alfa de Estrogênio/metabolismo , Estrogênios/farmacologia , Masoprocol/farmacologia , Miócitos de Músculo Liso/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/metabolismo , Angiotensina II/farmacologia , Animais , Aorta Torácica/citologia , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Di-Hidrotestosterona/farmacologia , Estriol/farmacologia , Receptor alfa de Estrogênio/genética , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Fosforilação/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , RNA Interferente Pequeno/genética , Ratos Sprague-DawleyRESUMO
The present study aimed to investigate the dose-dependent modulating effect of estriol (E3), an estrogen predominantly produced during human pregnancy, on antigeninduced production of specific antibodies in female BALB/c mice. The animals were immunized either with bovine serum albumin (BSA) or the pneumococcal polysaccharide serotype-14 (PPS-14), and the levels of specific serum antibodies were determined using ELISA kits. E3 was found to have very different effects on antigen-induced production of specific antibodies in animals immunized with these two antigens. While E3 stimulated the production of PPS-14-specific antibodies, it suppressed the production of BSA-specific antibodies. The results also demonstrated that the modulating effect of E3 on the production of antigenspecific antibodies depends on the dose of E3 used. For BSAinduced antibody production, E3 had a dosedependent inhibitory effect, whereas for PPS14specific antibody (Ab) production, E3 exerted the strongest stimulation at a lower dose, and produced less stimulation at higher doses. E3 caused thymus atrophy in animals immunized with either PPS14 or BSA, but only induced spleen atrophy in BSAinjected mice. These observations suggest that E3 increases the ability of a pregnant female to avoid bacterial infections while decreasing the incidence of autoimmune responses against circulating components from either the fetus or pregnant female.
Assuntos
Estriol/farmacologia , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Animais , Anticorpos Antibacterianos/biossíntese , Especificidade de Anticorpos/efeitos dos fármacos , Cápsulas Bacterianas/imunologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Sistema Imunitário/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Gravidez , Soroalbumina Bovina/imunologiaRESUMO
Production of recombinant human apolipoprotein A-I (apoA-I) in E. coli cells is described and its biological properties are compared with those of natural protein. Recombinant apoA-I was isolated as a chimeric polypeptide and then processed to a mature form apoA-I (rapo-I). We studied the ability of the resulting protein to penetrate into hepatocyte nuclei and regulate the rate of DNA biosynthesis in complex with estriol. Penetration of rapoA-I conjugated with FITC into hepatocyte nuclei was demonstrated. rapoA-I-estriol and apoA-I-estriol complexes induced similar increase in DNA biosynthesis rate in isolated hepatocytes, which confi rms functional similarity of the obtained recombinant mature protein (rapoA-I) and native human apoA-I.
Assuntos
Apolipoproteína A-I/farmacologia , Apolipoproteína A-I/genética , Apolipoproteína A-I/isolamento & purificação , Nucléolo Celular/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Replicação do DNA/efeitos dos fármacos , Escherichia coli , Estriol/farmacologia , Fluoresceína-5-Isotiocianato , Corantes Fluorescentes , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/farmacologiaRESUMO
Oral hormone replacement therapy (HRT) based on estradiol-17ß (E2) greatly increases circulating estrone (E1) levels. E1 is an estrogen receptor agonist but may also be a partial E2 antagonist. We investigated the effects of circulating E1 on the association between circulating E2 and the increase in mammographic density (∂MD) in 46 healthy post-menopausal women treated with E2 2 mg and norethisterone acetate 1 mg daily. MD and serum E1 and E2 were measured before and after 6 months of treatment. At high E1 levels, ∂MD showed significant positive correlations leading to increase (∂-values) in both E1 and E2. Lowering the upper serum E1 limit strengthened the correlations to ∂E2 while the significant correlations to ∂E1 disappeared. E1 at high concentrations may act as a partial E2 antagonist also in the normal breast in vivo and disturb relationships between circulating E2 and biological estrogen effects. When investigating the relations between circulating steroids and their effects, structurally related compounds, which may act as partial antagonists, have to be considered, at least when they are present in higher concentrations.