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1.
BJOG ; 126(1): 65-72, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29992731

RESUMO

OBJECTIVE: To study vaginal as opposed to cervical human papillomavirus (HPV) acquisition with regard to true prevalence, HPV types, and the role of co-factors in virgins and after their sexual debut. DESIGN: Prospective epidemiological observational study. SETTING: University hospital specialised in genital malformations. POPULATION: Women diagnosed with Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS) and undergoing neovaginoplasty between November 2011 and July 2017. METHODS: This is a prospective study including 186 women with MRKHS before and after sexual debut. MAIN OUTCOME MEASURES: Conventional vaginal cytology and different HPV tests were performed at surgery and during routine gynaecological follow-up 1, 3, 6 and ≥ 11 months after surgery and risk factors were documented. RESULTS: The mean age of all women at surgery was 20.1 years (SD 5.4), mean body mass index (BMI) was 22.1 kg/m2 (SD 4.6). In 83 vaginal samples from 41 different women at least one of the HPV tests was positive. Thirty-three different HPV types were detected. The prevalence of 41/186 = 22.0% as well as type distribution are comparable with those found in a young German female population. The overall rate of acquisition was clearly associated with sexual activity and smoking habits. Out of 367 Papanicolaou smears only six were abnormal with Pap IIID (MN II) and no obvious vaginal lesion was detected. CONCLUSIONS: Vaginal HPV prevalence and HPV types in previously virgin women after creation of a neovagina are not different from the acquisition of cervical infections in the general population and is clearly associated with sexual activity and with smoking habits. However, abnormal Papanicolaou smears are rarely seen. TWEETABLE ABSTRACT: Vaginal HPV prevalence after creation of a neovagina is similar to that on the cervix in the general population.


Assuntos
Infecções por Papillomavirus/epidemiologia , Transtornos 46, XX do Desenvolvimento Sexual/complicações , Transtornos 46, XX do Desenvolvimento Sexual/cirurgia , Adolescente , Adulto , Anormalidades Congênitas/cirurgia , Feminino , Humanos , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/cirurgia , Teste de Papanicolaou/estatística & dados numéricos , Infecções por Papillomavirus/diagnóstico , Prevalência , Procedimentos de Cirurgia Plástica , Fatores de Risco , Comportamento Sexual/estatística & dados numéricos , Fumar/epidemiologia , Vagina/cirurgia , Adulto Jovem
2.
Climacteric ; 18(4): 444-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25958921

RESUMO

Due to experimental and clinical data, the hypothesis has been raised that a 'time gap' is necessary to achieve 'carcinoprotection' by estrogen therapy in postmenopausal women, possibly also in combination with certain ('neutral') progestogens. As the mechanism, apoptotic effects are discussed, which, however, would only work after long-term estrogen deprivation. Based on this hypothesis, in general, an early initiation of menopausal hormone therapy would increase the risk of breast cancer, in sharp contrast to the beneficial cardiovascular effects, only protective within the 'window of opportunity' directly after menopause. However, other mechanisms are possible which could work without a time gap, leading to a decreased risk of breast cancer or even being carcinoprotective compared with no treatment. For example, within estradiol metabolism, carcinoprotective enzymes can be upregulated and protective estradiol metabolites can be produced, as shown, for example, especially in women with balanced nutrition and physical activity. In addition, it has to be considered that a long time is needed to see any clinical effects based on the biological mechanisms which may start early after estrogen exposure. Thus, more research and studies are needed to prove the 'gap hypothesis', and it may be that estrogen is beneficial for a woman at any time of her life.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/prevenção & controle , Terapia de Reposição de Estrogênios , Estrogênios/uso terapêutico , Fatores Etários , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/metabolismo , Carcinogênese/efeitos dos fármacos , Estrogênios/metabolismo , Estrogênios/farmacologia , Feminino , Humanos , Menopausa/efeitos dos fármacos , Menopausa/metabolismo , Fatores de Tempo
3.
J Steroid Biochem Mol Biol ; 142: 62-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23994274

RESUMO

Evidence is growing that progestogens may enhance breast cancer risk under hormone therapy in the postmenopause or hormonal contraception. However, differences may exist within the progestogen class and certain progestogens may have a higher potency in terms of breast cancer risk. The mechanism(s) by which these progestogens might influence breast cancer risk appear to be mediated via genomic and/or non-genomic effects triggered by activated progestogen receptors. In general, regulation of gene expression by progestogen receptors seems to be a multifactorial process involving both actions which often converge. In the present review, we describe the known genomic and non-genomic effects in the breast, especially focusing on the progestins. This article is part of a Special Issue entitled 'Menopause'.


Assuntos
Progestinas/uso terapêutico , Mama , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Feminino , Humanos , Acetato de Medroxiprogesterona/farmacologia , Proteínas de Membrana/fisiologia , Pós-Menopausa , Progestinas/farmacologia , Receptores de Progesterona/fisiologia , Risco , Saúde da Mulher
4.
Climacteric ; 16(5): 509-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23758160

RESUMO

Hormone therapy may increase the risk of breast cancer. Thus, especially the addition of synthetic progestins may play a decisive role according to the results of clinical studies. Overexpression of a special receptor, i.e. the progesterone receptor membrane component-1 (PGRMC1), may offer a potential new pathway to explain the observed increase in breast cancer risk in the combined arm of the Women's Health Initiative. PGRMC1 is expressed in breast cancer tissue and may be important in tumorigenesis. The expression of PGRMC1 in breast cancer tissue is significantly different from that in normal mammary glands. Certain synthetic progestins can increase the proliferation of PGRMC1-overexpressing breast cancer cells and may thus be involved in tumorigenesis, while progesterone and certain synthetic progestins such as nomegestrol or chlormadinone acetate react neutrally. Our investigations point towards an important role of estrogen receptor-α in the signaling cascade, resulting in the proliferative effect induced by progestins. Thus, activation of PGRMC1 may explain the increased breast cancer risk observed during treatment with certain progestins. Very recently, PGRMC1 was investigated in serum samples of lung cancer patients and matched healthy patients; significantly higher concentrations were shown in the cancer patients. Therefore, PGRMC1 might be a predictor for other cancers as well but, according to clinical trials, its importance for a possible screening tool, particularly for breast cancer risk during hormone therapy, seems of interest.


Assuntos
Neoplasias da Mama/etiologia , Proteínas de Membrana/fisiologia , Receptores de Progesterona/fisiologia , Neoplasias da Mama/química , Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Receptor alfa de Estrogênio/fisiologia , Estrogênios/farmacologia , Feminino , Humanos , Células MCF-7 , Proteínas de Membrana/análise , Pós-Menopausa , Congêneres da Progesterona/efeitos adversos , Congêneres da Progesterona/farmacologia , Receptores de Progesterona/análise , Fatores de Risco , Transdução de Sinais , Saúde da Mulher
5.
Horm Metab Res ; 44(6): 415-21, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22488518

RESUMO

Currently the use of natural estradiol as estrogenic component in oral contraceptives is more and more extended. It is unknown whether the application of this estrogen is associated with a different breast cancer risk as compared to the common use of the synthetic ethinylestradiol. In addition with the intention to reduce menstruation associated symptoms and bleeding periods an extended-cycle regimen is currently considered. In the present in vitro work, we have compared the effect of these different estrogenic compounds and the different treatment regimens on breast cancer risk. Human breast cancer cells (ZR75-1 and HCC1500) were incubated with equimolar concentrations of estradiol or ethinylestradiol combined with various progestogens, dienogest, drospirenone, keto-desogestrel, levonorgestrel, and nomegestrel. Usual and extended cycle was mimicked by incubation periods of 3 days with 1 day hormones off and 4 days, respectively. Molecular markers for proliferation and apoptosis were investigated by Western blot. In both cell lines estradiol and ethinylestradiol elicited a significant increase in the proliferation rate without difference between the 2 estrogens. The effect in the long-term cycle tended to be more pronounced than in the intermitted cycle. Progestogen addition most significantly reduced the estrogen-induced proliferation rate. The molecular markers were influenced by the progestogens mostly in the same manner, reducing the proliferation/apoptosis rate. Our results indicate that both estrogenic based combinations with progestogens may not increase breast cancer risk independent from the regimen, intermitted or long-term cycle. However clinical studies are necessary to prove these in vitro results.


Assuntos
Neoplasias da Mama/patologia , Estradiol/farmacologia , Etinilestradiol/farmacologia , Progestinas/farmacologia , Western Blotting , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Feminino , Humanos , Fatores de Tempo
6.
Vet Microbiol ; 159(1-2): 69-76, 2012 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-22465798

RESUMO

In a breeding and fattening pig farm an increasing number of cases of abortion and generalized mycobacteriosis at slaughter occurred. Pathological findings compatible with mycobacteriosis, acid-fast organisms in tissues, and isolation of mycobacteria from tissue samples including fetuses, lungs and reproductive organs from sows, genital swabs, mesenteric lymph nodes, and from a sperm sample revealed the cause of the disease. Bacterial cultures were identified as Mycobacterium avium subsp. hominissuis using IS901-/IS1245-specific PCR. Genotyping of selected isolates from animals as well as from their environment by MIRU-VNTR analysis showed that the herd was infected with one single outbreak strain. The same genotype was also isolated from pigs of two other farms which showed comparable symptoms and were in direct contact with the index farm as well as from their environment. Immunological host responses detected by tuberculin skin test and ELISA gave positive results at herd level only. Despite the detection of other potential pathogens mycobacteria were regarded as the causative agent of the reproductive disorders. To our knowledge this is the first report of an epidemic mycobacterial infection in a pig holding associated with reproductive disorders, which could be attributed to one single virulent strain, and the first report of detection of M. avium subsp. hominissuis in pig sperm.


Assuntos
Surtos de Doenças , Mycobacterium avium/genética , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Tuberculose/veterinária , Aborto Animal/genética , Aborto Animal/virologia , Animais , Feminino , Genótipo , Masculino , Mycobacterium avium/classificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez , Espermatozoides/virologia , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/patologia , Teste Tuberculínico , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/microbiologia , Tuberculose/patologia
7.
Minerva Endocrinol ; 37(1): 59-74, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22382615

RESUMO

Evidence is increasing suggesting that adding progestogens to estrogens can increase the risk of breast cancer. However, our experimental data as a result of scientific collaboration between university of Tuebingen, Germany, and university of Beijing, China, comparing all available progestogens used in hormone therapy and hormonal contraception present high evidence that there may be differences regarding breast cancer risk. Especially of concern may be to differentiate between primary and secondary risk i.e. between the effect of on benign and malignant breast epithelial cells suggesting differences in primary risk and risk in patients after breast cancer. Of importance also is that in contrast to natural progesterone the apocrine impact of stromal growth factors and also certain cell components of breast epithelial cells can strongly increase proliferation rates of some (but not all. synthetic progestogens which can lead to clinical cancer before (in contrast to estrogen-only therapy. carcinoprotective mechanisms can work. Regarding clinical data, epidemiological studies and especially the Women's Health Initiative, so far the only prospective placebo-controlled study, demonstrate an increased risk under combined estrogen/progestogen-, but not under estrogen-only therapy. However, up to now the clinical studies cannot discriminate between the various progestogens mostly due to too small patient numbers in the subgroups, and in most studies either medroxyprogesterone acetate or norethisterone have been used. However, there is evidence that the natural progesterone and dydrogesterone, possibly also the transdermal usage of synthetic progestogens, may have less risks, but this must be proven in further clinical trials.


Assuntos
Neoplasias da Mama/induzido quimicamente , Estrogênios/efeitos adversos , Progestinas/efeitos adversos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Neoplasias da Mama/prevenção & controle , Células Cultivadas/efeitos dos fármacos , Cocarcinogênese , Estudos de Coortes , Anticoncepcionais Orais Hormonais/efeitos adversos , Método Duplo-Cego , Sinergismo Farmacológico , Células Epiteliais/efeitos dos fármacos , Terapia de Reposição de Estrogênios/efeitos adversos , Estrogênios/administração & dosagem , Estrogênios/farmacologia , Estrogênios/uso terapêutico , Medicina Baseada em Evidências , Feminino , Terapia de Reposição Hormonal/efeitos adversos , Humanos , Estudos Multicêntricos como Assunto/estatística & dados numéricos , Recidiva Local de Neoplasia/induzido quimicamente , Segunda Neoplasia Primária/induzido quimicamente , Pós-Menopausa , Progestinas/administração & dosagem , Progestinas/farmacologia , Progestinas/uso terapêutico , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Risco , Células Tumorais Cultivadas/efeitos dos fármacos
8.
Maturitas ; 71(4): 337-44, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22364708

RESUMO

Dienogest (DNG) is a 19-nortestosterone derivative (a C-19 progestogen) with a cyanomethyl instead of an ethinyl group at the C-17 position, which may make the compound elicit fewer hepatic effects than other C-19 nortestosterone derivatives. Its similarity to norethisterone is reflected in its high endometrial efficacy, which could explain the high stability of the menstrual cycle women achieve when they use DNG in combination with ethinyl estradiol (EE) or with estradiol valerate (E2V). Its strong endometrial efficacy underlies the use of DNG (on its own) to treat endometriosis, and gives it antiproliferative and anti-inflammatory effects in the treatment of endometriotic lesions. Properties derived from its C-19 derivative structure include its short plasma half-life, of about 10h (which means the drug is not accumulated), and its high oral bioavailability, of more than 90%. However, DNG also has some of the properties of typical of progesterone derivatives, including a lack of effect on the metabolic and cardiovascular systems, and considerable antiandrogenic activity, the latter increased by its lack of affinity to the sex-hormone binding globulin (SHBG), in contrast to other C-19 progestogens. DNG has no glucocorticoid and no antimineralocorticoid activity. It also has no antiestrogenic activity, which suggests that it should not antagonize estradiol's beneficial effects. This is important for its use in the treatment of endometriosis, because, due to DNG's low gonadotropic activity, E2 levels are not decreased to zero, in contrast to treatments with gonadotropin-releasing hormone (GnRH) analogues. This maintenance beneficial E2 effects is of particular importance for the general tolerability of the first contraceptive pill to use E2V instead of EE, although clinical endpoint studies are still ongoing. These studies are expected, on the basis of its pharmacology, to demonstrate the cardiovascular safety of the new pill.


Assuntos
Anticoncepcionais Orais/farmacologia , Endometriose/tratamento farmacológico , Endométrio/efeitos dos fármacos , Ciclo Menstrual/efeitos dos fármacos , Nandrolona/análogos & derivados , Progestinas/farmacologia , Anticoncepcionais Orais/uso terapêutico , Feminino , Humanos , Nandrolona/farmacologia , Nandrolona/uso terapêutico , Progestinas/uso terapêutico
9.
Climacteric ; 15(5): 467-72, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22335423

RESUMO

OBJECTIVES: Evidence is accumulating that progestogens may play a crucial role in the development of breast cancer under contraception and hormone therapy in reproductive and menopausal women. Progesterone receptor membrane component 1 (PGRMC1) expressed in breast cancer may be important in tumorigenesis and thus may increase breast cancer risk. The aim of this project was to investigate the influence of progesterone and nine synthetic progestins on MCF-7 breast cancer cells overexpressing PGRMC1. METHODS: MCF-7 cells were stably transfected with PGRMC1 expression plasmid (WT-12). To test the effects of progestogerone (P) and the synthetic progestins chlormadinone acetate (CMA), desogestrel (DSG), drospirenone (DRSP), dydrogesterone (DYD), levonorgestrel (LNG), medroxyprogesterone acetate (MPA), nomegestrol (NOM) and norethisterone (NET) on cell proliferation, MCF-7 and WT-12 cells were stimulated with different concentrations (0.01-1 µmol/l). RESULTS: In MCF-7 cells, DRSP, DSG, DYD, LNG and NET increased the proliferation at 1 µmol/l, the effect being highest for NET with about 20%. In WT-12 cells, the same progestins, but additionally MPA, showed a significant increase, which was much higher (30-245%) than in MCF-7 cells. Here again, NET showed the highest proliferative effect. No effect was found for CMA, NOM and P. CONCLUSION: Some synthetic progestins trigger a proliferative response of PGRMC1-overexpressed MCF-7 cancer cells. The effect of progestogens on breast cancer tumorigenesis may clearly depend on the specific pharmacology of the various synthetic progestins.


Assuntos
Neoplasias da Mama/patologia , Membrana Celular/fisiologia , Proliferação de Células/efeitos dos fármacos , Progestinas/farmacologia , Neoplasias da Mama/genética , Feminino , Expressão Gênica , Humanos , Células MCF-7 , Acetato de Medroxiprogesterona/farmacologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Noretindrona/farmacologia , Progesterona/farmacologia , Congêneres da Progesterona/farmacologia , Receptores de Progesterona/genética , Receptores de Progesterona/fisiologia , Transfecção
11.
Steroids ; 75(10): 625-31, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20214913

RESUMO

In the last decade the endogenous estradiol metabolite, 2-methoxyestradiol (2ME), has gained more and more interest due to its marked anticancerogenic properties and possible cardiovascular benefits, as shown in numerous animal and experimental investigations. Some promising results in terms of the usage of 2ME as a therapeutic agent were obtained by various clinical studies in patients with breast cancer and prostate cancer. However, one main problem appears to be the bioavailability of 2ME, therefore new formulations are now in the test phase. In this review, the most important aspects of the biology and molecular mechanisms of 2ME are summarized.


Assuntos
Antineoplásicos/farmacologia , Estradiol/análogos & derivados , 2-Metoxiestradiol , Animais , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Estradiol/metabolismo , Estradiol/farmacologia , Estradiol/uso terapêutico , Feminino , Humanos , Masculino , Modelos Biológicos , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo
12.
Biophys J ; 97(4): 1067-76, 2009 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-19686654

RESUMO

Supported lipid bilayers composed of 1-palmitoyl-2-oleoyl-phosphatidylethanolamine (POPE) and 1-palmitoyl-2-oleoyl-phosphatidylglycerol (POPG) were assembled by the vesicle fusion technique on mica and studied by temperature-controlled atomic force microscopy. The role of different physical parameters on the main phase transition was elucidated. Both mixed (POPE/POPG 3:1) and pure POPE bilayers were studied. By increasing the ionic strength of the solution and the incubation temperature, a shift from a decoupled phase transition of the two leaflets, to a coupled transition, with domains in register, was obtained. The observed behavior points to a modulation of the substrate/bilayer and interleaflet coupling induced by the environment and preparation conditions of supported lipid bilayers. The results are discussed in view of the role of different interactions in the system. The influence of the substrate on the lipid bilayers, in terms of interleaflet coupling, can also help us in understanding the possible effect that submembrane elements like the cytoskeleton might have on the structure and dynamics of biomembranes.


Assuntos
Bicamadas Lipídicas/química , Fluidez de Membrana , Modelos Químicos , Modelos Moleculares , Fosfatidiletanolaminas/química , Fosfatidilgliceróis/química , Simulação por Computador , Conformação Molecular
14.
Climacteric ; 12(3): 230-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19340614

RESUMO

OBJECTIVE: Progesterone influences mammary gland development and probably breast cancer tumorigenesis and functions by regulating a broad spectrum of physiological processes. We investigated receptor membrane-initiated actions of progesterone in MCF-7 breast cancer cells via progesterone receptor membrane component 1 (PGRMC1). DESIGN AND METHOD: The expression of PGRMC1 in breast cancer was verified by immune fluorescent analysis of paraffin sections. MCF-7 cells were transfected with PGRMC1 (wild type) or PGRMC1 variants. These cells were stimulated with a membrane-impermeable progesterone (P4) conjugate (P4-BSA-fluorescein isothiocyanate, P4-BSA-FITC, 10(-6) mol/l) or unconjugated progesterone (P4, 10(-6) mol/l) in the presence or absence of the progesterone receptor blocker RU-486 (10(-6) mol/l). Additionally, the effects on the expression of vascular endothelial growth factor A (VEGF-A) were determined using quantitative real-time polymerase chain reaction. RESULTS: PGRMC1 is perinuclearly localized in breast cancer cells. Western Blot analysis suggests that PGRMC1 is phosphorylated at serine 180. MCF-7-PGRMC1 (S180A) cells show an approximately 35% increase in proliferation after incubation with P4-BSA-FITC compared to MCF-7 control and MCF-7-PGRMC1 (wild type) cells. This effect cannot be blocked by RU-486. P4 reduced proliferation of MCF-7-PGRMC1 cells by approximately 10% compared to untreated controls. P4-BSA-FITC treatment led to a roughly three-fold activation of VEGF-A gene expression compared to MCF-7 cells. CONCLUSION: PGRMC1 is expressed in breast cancer tissue and mediates an RU-486-independent proliferative signal. It might also contribute to VEGF-induced neovascularization in tumor tissue. Thus, screening for PGRMC1 expression might be of interest to identify women with a higher expression of PGRMC1 and who might thus be susceptible for breast cancer development under hormone replacement therapy.


Assuntos
Neoplasias da Mama/metabolismo , Proteínas de Membrana/metabolismo , Progesterona/análogos & derivados , Progesterona/farmacologia , Progestinas/farmacologia , Receptores de Progesterona/metabolismo , Soroalbumina Bovina/farmacologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Western Blotting , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Antagonistas de Hormônios/farmacologia , Humanos , Mifepristona/farmacologia , Fosforilação , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Transfecção , Fator A de Crescimento do Endotélio Vascular/genética
15.
Biochim Biophys Acta ; 1788(3): 600-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19150329

RESUMO

Monte Carlo (MC) simulations, Differential Scanning Calorimetry (DSC) and Fourier Transform InfraRed (FTIR) spectroscopy were used to study the melting behavior of individual lipid components in two-component membranes made of DMPC and DSPC. We employed Monte Carlo simulations based on parameters obtained from DSC profiles to simulate the melting of the different lipids as a function of temperature. The simulations show good agreement with the FTIR data recorded for deuterated and non-deuterated lipids, which demonstrates that the information on the differential melting of the individual components is already contained in the calorimetric profiles. In mixtures, both lipids melt over a wide temperature range. As expected, the lipid melting events of the lipid with the lower melting temperature occur on average at lower temperatures. The simulations also yield information on the lateral distribution of the lipids that is neither directly contained in the DSC nor in the FTIR data. In the phase coexistence region, liquid disordered domains are typically richer in the lower-melting-temperature lipid species.


Assuntos
Dimiristoilfosfatidilcolina/química , Bicamadas Lipídicas/química , Fosfatidilcolinas/química , Varredura Diferencial de Calorimetria , Simulação por Computador , Método de Monte Carlo , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
16.
Climacteric ; 12(1): 80-7, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18979300

RESUMO

OBJECTIVES: The effect of the new progestogen drospirenone on biochemical markers in terms of cardiovascular effects was investigated in the presence and absence of aldosterone and compared to progesterone and the progestogens medroxyprogesterone acetate (MPA) and promegestone (R5020), and the antimineralocorticoid spironolactone. METHODS: Human female aortic endothelial cells were used for the experiments. The progestogens were tested alone at 0.1 and 10 micromol/l and in combination with aldosterone at a concentration of 10 micromol/l. The adhesion molecule E-selectin, the chemokine monocyte attracting protein-1 (MCP-1) and plasminogen activator inhibitor-1 (PAI-1) were chosen as markers. RESULTS: In combination with aldosterone, spironolactone, drospirenone, progesterone and R5020 were able to inhibit the aldosterone-induced increase in MCP-1 concentration, the effect being greatest for spironolactone. In contrast, MPA did not show any significant effect. For E-selectin, similar results were found; however, R5020 and MPA were not able to act antagonistically. Spironolactone, drospirenone and progesterone were able to significantly reduce the aldosterone-induced stimulation of PAI-1. For MPA and R5020, no significant effect was found. CONCLUSIONS: The new progestogen drospirenone seems to have favorable effects on the cardiovascular system due to its antimineralocorticoid property. Clinical studies must prove the results of this in vitro experiment.


Assuntos
Androstenos/farmacologia , Biomarcadores/análise , Sistema Cardiovascular/efeitos dos fármacos , Células Endoteliais/química , Antagonistas de Receptores de Mineralocorticoides/farmacologia , Adolescente , Aldosterona/farmacologia , Aorta , Cardiotônicos , Células Cultivadas , Quimiocina CCL2/análise , Vasos Coronários , Selectina E/análise , Células Endoteliais/efeitos dos fármacos , Feminino , Humanos , Inibidor 1 de Ativador de Plasminogênio/análise , Progesterona/farmacologia , Congêneres da Progesterona/farmacologia , Promegestona/farmacologia , Espironolactona/farmacologia
17.
Climacteric ; 11(5): 409-15, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18781486

RESUMO

OBJECTIVES: Tibolone is often taken concurrently with soy. Tibolone, soy and equol-producing capacity each affect vascular health, whereas their concomitant effects are unknown. We studied the effects of soy on sex steroids and vascular inflammation markers in long-term tibolone users. METHODS: Postmenopausal women (n = 110) on tibolone were screened with a soy challenge to find 20 equol producers and 20 non-producers. All women were treated for 8 weeks in a cross-over trial with soy (52 g of soy protein containing 112 mg of isoflavones) or placebo. Serum estrone, 17beta-estradiol, testosterone, androstenedione, dehydroepiandrosterone sulfate (DHEAS), sex hormone binding globulin (SHBG), C-reactive protein (CRP), vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1), and platelet-selectin (P-selectin) were assessed. RESULTS: Soy decreased (7.1%) the estrone level, significantly (12.5%) only in equol producers (from 80.2 +/- 10.8 to 70.3 +/- 7.0 pmol/l; p = 0.04). Testosterone was reduced (15.5%; from 586 +/- 62.6 to 495 +/- 50.1 pmol/l, p = 0.02) during soy treatment, and more markedly in equol producers than non-producers (22.1% vs. 10.0%). No changes appeared in SHBG, CRP or ICAM-1, but VCAM-1 increased (9.2%) and P-selectin decreased (10.3%) during soy treatment. CONCLUSIONS: Soy modified the concentrations of estrone, testosterone and some endothelial markers. Equol production enforced these effects. Soy supplementation may be clinically significant in tibolone users.


Assuntos
Moduladores de Receptor Estrogênico/uso terapêutico , Isoflavonas/metabolismo , Norpregnenos/uso terapêutico , Pós-Menopausa , Proteínas de Soja/administração & dosagem , Proteína C-Reativa/análise , Estudos Cross-Over , Equol , Estrona/sangue , Feminino , Humanos , Molécula 1 de Adesão Intercelular/sangue , Pessoa de Meia-Idade , Selectina-P/sangue , Globulina de Ligação a Hormônio Sexual/análise , Testosterona/sangue , Molécula 1 de Adesão de Célula Vascular/sangue
18.
Horm Metab Res ; 40(3): 206-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18197584

RESUMO

Many women would prefer fewer bleeding episodes while taking oral contraceptives. For this reason and with the intention of reducing menstruation-associated symptoms, an extended-cycle contraceptive is considered in the present paper. However, it remains unknown whether this long-term treatment is associated with a different breast cancer risk from that of the usual treatment. Therefore, in the present in vitro work we intend to compare the effect of these different treatment regimens on breast cancer risk. MCF-7 cells (human estrogen- and progesterone-receptor-positive metastatic breast cancer cells) and HCC1500 cells (human estrogen- and progesterone-receptor-positive primary breast cancer cells) were incubated with physiological concentrations of ethinylestradiol (EE). Usual and extended cycles were mimicked by incubation periods of 18 hours with EE followed by 6 hours without EE and 24 hours with EE for 3 days, respectively. In both cell lines, EE elicited a significant increase in the proliferation rate. No significant difference was found between the two incubation periods. Our results indicate that continuously administered ethinylestradiol may not increase breast cancer risk in comparison to intermittent application. However, clinical studies are necessary to prove these in vitro results.


Assuntos
Neoplasias da Mama/patologia , Proliferação de Células/efeitos dos fármacos , Estrogênios/farmacologia , Etinilestradiol/farmacologia , Neoplasias da Mama/tratamento farmacológico , Relação Dose-Resposta a Droga , Feminino , Humanos , Neoplasias Hormônio-Dependentes , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Climacteric ; 10 Suppl 2: 62-5, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17882675

RESUMO

Certain estrogen metabolites can act as carcinogens in in vitro and animal experiments. The clinical relevance remains unclear. However, in the presence of factors that could influence estradiol metabolism, such as smoking or genetic polymorphisms, it seems prudent to prefer transdermal therapy to minimize the production of possible toxic metabolites. In addition, various defense mechanisms operate in the physiologic human body that prevent the formation of possible toxic intermediate products of estradiol metabolism, especially during oxidative stress. Only under rare special conditions is it conceivable that the human body cannot react sufficiently.


Assuntos
Neoplasias da Mama/induzido quimicamente , Carcinógenos/toxicidade , Estradiol/análogos & derivados , Estriol/análogos & derivados , Terapia de Reposição de Estrogênios/efeitos adversos , Esteroide 16-alfa-Hidroxilase/toxicidade , Administração Cutânea , Animais , Neoplasias da Mama/metabolismo , Estradiol/toxicidade , Estriol/toxicidade , Estrogênios de Catecol , Feminino , Humanos
20.
Maturitas ; 58(1): 42-9, 2007 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-17572028

RESUMO

OBJECTIVES: Tibolone is a tissue selective compound with estrogenic, androgenic and progestogenic properties in classical bioassays. It is used for alleviation of menopausal symptoms and for osteoporosis prophylaxis in postmenopausal women. Only few data are available regarding the effects of tibolone on the cardiovascular system. We investigated therefore the in vitro effects of tibolone and its metabolites on the vasculature under special controlled conditions, using human female coronary endothelial and smooth muscle cells. METHODS: The effect on the production of the following markers in endothelial cells from human female coronary arteries was evaluated: nitric oxide synthase, prostacyclin, endothelin, plasminogen-activator-inhibitor-1 (PAI-1), E-Selectin, Intercellular adhesion molecule (ICAM-1), monocyte attracting protein-1 (MCP-1) and the precursor of matrix metalloproteinase-1 (pro-MMP-1). Tibolone, its metabolites, estradiol (E2), E2/norethisterone (NET) and E2/medroxyprogesterone acetate (MPA) were tested at 0.1 microM and 1 microM. The markers were determined by enzyme immunoassays in the cell supernatant. Cell proliferation of smooth muscle cells from female coronary artery was measured by an adenosine triphosphate-assay. RESULTS: Tibolone, its 3-hydroxy metabolites, E2/NET, E2/MPA and estradiol alone had significant effects on the synthesis of all markers tested. The magnitude of the tibolone effects, however, was mostly smaller than that of E2/NET and E2/MPA. Concerning smooth muscle cells tibolone and its 3-hydroxy metabolites also elicited an inhibition of the proliferation compared to control values. The strongest effect here was found for E2/NET and E2 alone, whereas E2/MPA had no effect. CONCLUSION: The results of this in vitro study conducted with cells of the most important vascular bed with respect to the problem of cardiovascular risk suggest that tibolone can positively influence the vasculature. However, these tibolone effects may depend on intact vascular cells and may vary due to the different atherosclerotic stages of the vessels. Thus, experimental studies are useful to explore mechanisms, but clearly cannot replace clinical studies.


Assuntos
Biomarcadores/sangue , Vasos Coronários/citologia , Endotélio Vascular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Norpregnenos/farmacologia , Células Cultivadas , Vasos Coronários/efeitos dos fármacos , Selectina E/sangue , Endotelinas/sangue , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Epoprostenol/sangue , Estradiol/farmacologia , Feminino , Humanos , Molécula 1 de Adesão Intercelular/sangue , Metaloproteinase 1 da Matriz/sangue , Acetato de Medroxiprogesterona/farmacologia , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Óxido Nítrico Sintase/sangue , Noretindrona/farmacologia , Inibidor 1 de Ativador de Plasminogênio/sangue , Resistência Vascular/efeitos dos fármacos
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