808 resultados para sex hormones


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Background. The link between endogenous estrogen, coronary artery disease (CAD), and death in postmenopausal women is uncertain. We analyzed the association between death and blood levels of estrone in postmenopausal women with known coronary artery disease (CAD) or with a high-risk factor score for CAD. Methods. 251 postmenopausal women age 50-90 years not on estrogen therapy. Fasting blood for estrone and heart disease risk factors were collected at baseline. Women were grouped according to their estrone levels (<15 and >= 15 pg/mL). Fatal events were recorded after 5.8 perpendicular to 1.4 years of followup. Results. The Kaplan-Meier survival curve showed a significant trend (P = 0.039) of greater all-cause mortality in women with low estrone levels (< 15 pg/mL). Cox multivariate regression analysis model adjusted for body mass index, diabetes, dyslipidemia, family history, and estrone showed estrone (OR = 0.45; P = 0.038) as the only independent variable for all-cause mortality. Multivariate regression model adjusted for age, body mass index, hypertension, diabetes, dyslipidemia, family history, and estrone showed that only age (OR = 1.06; P = 0.017) was an independent predictor of all-cause mortality. Conclusions. Postmenopausal women with known CAD or with a high-risk factor score for CAD and low estrone levels (< 15 pg/mL) had increased all-cause mortality.

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Objective Vasoactive intestinal peptide (VIP) is a neuropeptide with elevated expression in regions that control urogenital functions. Estrogen appears to modulate VIP expression in various organs, but this effect has not been demonstrated in the vaginal wall. The aim of this study was to evaluate the influence of estrogen status on VIP expression in vessels of the vaginal wall. Methods Surgical specimens were removed from the vaginal walls of 18 premenopausal women and 12 postmenopausal women who were given surgery for genital prolapse grade I or II. Vaginal specimens were stained with estrogen receptor-alpha (ER-alpha) and VIP antibodies. Levels of follicle stimulating hormone (FSH), estradiol, prolactin, fasting glucose and serum thyroxine stimulating hormone were also measured. Estrogen status was assessed on the basis of FSH and ER-alpha scores. Results The vaginal walls of premenopausal women had significantly higher ER-alpha scores than those of menopausal women (premenopausal group, 3.6 +/- 2.2; menopausal group, 1.4 +/- 1.8; p = 0.01). Premenopausal women also had significantly higher levels of VIP in the vaginal wall than menopausal women (p = 0.02). Increasing age was associated with lower level of VIP staining (odds ratio 0.88; 95% confidence interval 0.78-0.99). Conclusion Levels of ER-alpha and VIP expression in the posterior vaginal wall were higher in premenopausal than in menopausal women, but VIP expression was not associated with estrogen status. Age was an independent predictor of VIP staining in vaginal wall biopsies.

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Background: Variations in maternal care are associated with neonatal stress, hormonal disturbances and reproductive injuries during adulthood. However, the effects of these variations on sex hormones and steroid receptors during ovary development remain undetermined. This study aimed to investigate whether variations in maternal care are able to influence the hormonal profile, follicular dynamics and expression of AR, ER-alpha and ER-beta in the ovaries of UCh rat offspring. Methods: Twenty-four adult UCh rats, aged 120 days, were randomly divided into two groups (UChA and UChB) and mated. Maternal care was assessed from birth (day 0) to the 10th postnatal day (PND). In adulthood, twenty adult female rats (UChA and UChB offspring; n = 10/group), aged 120 days, were euthanized by decapitation during the morning estrus. Results: UChA females (providing high maternal care) more frequently displayed the behaviors of carrying pups, as well as licking/grooming and arched back nursing cares. Also, mothers providing high care had elevated corticosterone levels. Additionally, offspring receiving low maternal care showed the highest estrous cycle duration, increased corticosterone and 17beta-estradiol levels, overexpression of receptors ER-alpha and ER-beta, increased numbers of primordial, antral and mature follicles and accentuated granulosa cell proliferation. Conclusions: Our study suggests that low maternal care alters corticosterone and 17beta-estradiol levels, disrupting the estrous cycle and folliculogenesis and differentially regulating the expression of ER-alpha and ER-beta in the ovaries of adult rats.

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It is well established that female sex hormones have a pivotal role in inflammation. For instance, our group has previously reported that estradiol has proinflammatory actions during allergic lung response in animal models. Based on these findings, we have decided to further investigate whether T regulatory cells are affected by female sex hormones absence after ovariectomy. We evaluated by flow cytometry the frequencies of CD4+Foxp3+ T regulatory cells (Tregs) in central and peripheral lymphoid organs, such as the thymus, spleen and lymph nodes. Moreover, we have also used the murine model of allergic lung inflammation a to evaluate how female sex hormones would affect the immune response in vivo. To address that, ovariectomized or sham operated female Balb/c mice were sensitized or not with ovalbumin 7 and 14 days later and subsequently challenged twice by aerosolized ovalbumin on day 21. Besides the frequency of CD4+Foxp3+ T regulatory cells, we also measured the cytokines IL-4, IL-5, IL-10, IL-13 and IL-17 in the bronchoalveolar lavage from lungs of ovalbumine challenged groups. Our results demonstrate that the absence of female sex hormones after ovariectomy is able to increase the frequency of Tregs in the periphery. As we did not observe differences in the thymus-derived natural occurring Tregs, our data may indicate expansion or conversion of peripheral adaptive Tregs. In accordance with Treg suppressive activity, ovariectomized and ovalbumine-sensitized and challenged animals had significantly reduced lung inflammation. This was observed after cytokine analysis of lung explants showing significant reduction of pro-inflammatory cytokines, such as IL-4, IL-5, IL-13 and IL-17, associated to increased amount of IL-10. In summary, our data clearly demonstrates that OVA sensitization 7 days after ovariectomy culminates in reduced lung inflammation, which may be directly correlated with the expansion of Tregs in the periphery and further higher IL-10 secretion in the lungs.

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Physiologically during puberty and adolescence, when juvenile acne usually appears, the response to a glucose load is increased if compared to the one observed in adult and at pre-pubertal age, while insulin sensitivity is reduced. Insulin is a hormone that acts at different levels along the axis which controls the sex hormones. It increases the release of LH and FSH by pituitary gland, stimulates the synthesis of androgens in the gonads and stimulates the synthesis of androgenic precursors in adrenal glands. Finally, it acts in the liver by inhibiting the synthesis of Sex Hormone Binding Globulin (SHBG). Insulin is also able to act directly on the production of sebum and amplify the effects of Iinsulin Growth Factor-1 in the skin, inhibiting the synthesis of its binding protein (IGF Binding Protein-1). In female subjects with acne and Polycystic Ovary Syndrome (PCOS) insulin resistance is a well known pathogenetic factor, while the relationship between acne and insulin resistance has been poorly investigated in males so far. The purpose of this study is to investigate the correlation between insulin resistance and acne in young males who do not respond to common therapies. Clinical and biochemical parameters of glucose, lipid metabolism, androgens and IGF-1 were evaluated. Insulin resistance was estimated by Homeostasis Model assessment (HOMA-IR) and Oral Glucose Tolerance Test was also performed. We found that subjects with acne had higher Sistolic and Diastolic Blood Pressure, Waist/Hip Ratio, Waist Circumference, 120' OGTT serum insulin and serum IGF-1 and lower HDL-cholesterol than subjects of comparable age and gender without acne. The results thus obtained confirmed what other authors have recently reported about a metabolic imbalance in young males with acne. Furthermore, these results support the hypothesis that insulin resistance might play an important role in the pathogenesis of treatment-resistant acne in males.

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Sex hormones influence immune responses and the development of autoimmune diseases including MS and its animal model, EAE. Although it has been previously reported that ovariectomy could worsen EAE, the mechanisms implicated in the protective action of endogenous ovarian hormones have not been addressed. In this report, we now show that endogenous estrogens limit EAE development and CNS inflammation in adult female mice through estrogen receptor expression in the host non-hematopoietic tissues. We provide evidence that the enhancing effect of gonadectomy on EAE development was due to quantitative rather than qualitative changes in effector Th1 or Th17 cell recruitment into the CNS. Consistent with this observation, adoptive transfer of myelin oligodendrocyte glycoprotein-specific encephalitogenic CD4(+) T lymphocytes induced more severe EAE in ovariectomized mice as compared to normal female mice. Finally, we show that gonadectomy accelerated the early recruitment of inflammatory cells into the CNS upon adoptive transfer of encephalitogenic CD4(+) T cells. Altogether, these data show that endogenous estrogens, through estrogen receptor , exert a protective effect on EAE by limiting the recruitment of blood-derived inflammatory cells into the CNS.

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Changes in the levels of female sex hormones during the menstrual cycle may cause cyclic differences in subgingival bacterial colonization patterns. The purpose of the present study was to test the hypothesis that hormonal changes in the menstrual cycle cause changes in the oral microbiota. METHODS: Bacterial plaque samples were collected in 20 systemically and periodontally healthy women using no hormonal contraceptives (test group) over a period of 6 weeks. Twenty age-matched systemically and periodontally healthy men were assigned to the control group. Samples were processed by checkerboard DNA-DNA hybridization assay, and 74 species were analyzed. RESULTS: No cyclic pattern of bacterial colonization was identified for any of the 74 species studied in women not using hormonal contraceptives. Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans) (Y4) was common at the beginning of menstruation (mean: 32%) and increased during the following 2 weeks (36%) in women (P <0.05). No cyclic differences in bacterial presence were found among the men (P values varied between 0.14 and 0.98). Men presented with significantly higher bacterial counts for 40 of 74 species (P <0.001), including Staphylococcus aureus and Pseudomonas aeruginosa but not Porphyromonas gingivalis (P = 0.15) or Tannerella forsythia (previously T. forsythensis) (P = 0.42). CONCLUSIONS: During a menstruation period, cyclic variation in the subgingival microbiota of periodontally healthy women of child-bearing age who were not using oral hormonal contraceptives could not be confirmed. Male control subjects presented with higher levels of many species but also without a cyclic pattern.

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This study investigated the contribution of estrogen receptors (ERs) alpha and beta for epicardial coronary artery function, vascular NO bioactivity, and superoxide (O(2)(-)) formation. Porcine coronary rings were suspended in organ chambers and precontracted with prostaglandin F(2alpha) to determine direct effects of the selective ER agonists 4,4',4''-(4-propyl-[(1)H]pyrazole-1,3,5-triyl)tris-phenol (PPT) or 2,3-bis(4-hydroxyphenyl)-propionitrile (DPN) or the nonselective ER agonist 17beta-estradiol. Indirect effects on contractility to U46619 and relaxation to bradykinin were assessed and effects on NO, nitrite, and O(2)(-) formation were measured in cultured cells. Within 5 minutes, selective ERalpha activation by PPT, but not 17beta-estradiol or the ERbeta agonist DPN, caused rapid, NO-dependent, and endothelium-dependent relaxation (49+/-5%; P<0.001 versus ethanol). PPT also caused sustained endothelium- and NO-independent vasodilation similar to 17beta-estradiol after 60 minutes (72+/-3%; P<0.001 versus ethanol). DPN induced endothelium-dependent NO-independent relaxation via endothelium-dependent hyperpolarization (40+/-4%; P<0.01 versus ethanol). 17beta-Estradiol and PPT, but not DPN, attenuated the responses to U46619 and bradykinin. All of the ER agonists increased NO and nitrite formation in vascular endothelial but not smooth muscle cells and attenuated vascular smooth muscle cell O(2)(-) formation (P<0.001). ERalpha activation had the most potent effects on both nitrite formation and inhibiting O(2)(-) (P<0.05). These data demonstrate novel and differential mechanisms by which ERalpha and ERbeta activation control coronary artery vasoreactivity in males and females and regulate vascular NO and O(2)(-) formation. The findings indicate that coronary vascular effects of sex hormones differ with regard to affinity to ERalpha and ERbeta, which will contribute to beneficial and adverse effects of hormone replacement therapy.

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Every year around 100 million male piglets are castrated in the EU, usually without anaesthesia or post-operative analgesia. This surgical intervention is painful and stressful. Several main players within the pig industry have voluntarily agreed to end the practice of surgical pig castration in the EU by 2018. One alternative to castration is entire male pig production. However, entire males behave differently than castrates, for example, by performing more mounting behaviour, which is suggested to be a welfare problem. The aim of our study was to develop a comprehensive ethogram of different types of mounting and to investigate properties, causes and consequences of mounting behaviour in finishing pigs. The study included 80 entire male and 80 female pigs from two farrowing batches born six weeks apart. Mixed sex and single-sex housing of pigs are both common in pig farming, so to ensure our study was representative, the 160 pigs were assigned to social groups of 20 in three treatments: entire male pigs only (MM, 2 groups, n = 40), entire females only (FF, 2 groups, n = 40) and entire males and females mixed together (MF, 4 groups, n = 80). Measurements took place during the final six weeks before slaughter (between 63.5 and 105.5 kg). Observations of mounting behaviour on 12 days per batch suggested that: (i) males mounted more than females, (ii) within sex, there was no effect of treatment on the amount of mounting (although the statistical power of the study to detect these effects was low), and (iii) there were individual differences in mounting that were stable over time (within sex). Classification of mounting into different categories revealed that sexual mounting was most common overall and in males but only rare in females. Compared to other types of mounting (e.g. caused by crowding or during a fight), sexual mounts lasted longer and provoked more screaming by the recipient. There were no relationships between mounting behaviour on the one hand and dominance rank in food competition tests, the circulating levels of sex hormones (oestradiol, testosterone and progesterone) at the end of the study, the health scores (lameness and scratches) or weight gain on the other hand. The stable individual differences of mounting over time suggest that mounting behaviour is a trait of the individual rather than the appearance of random outbreaks. However, these differences in mounting cannot be explained by dominance behaviour or by differences in sex hormone concentrations that could indicate the onset of puberty. Mounting behaviour and in particular sexual mounting provoked high pitched screaming of the recipients indicating that mounting is a welfare problem. For the welfare assessment of entire male pig production the performance of mounting behaviour should be considered. (C) 2013 Elsevier B.V. All rights reserved.

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There is growing support for the theory that an interaction between the immune and reproductive/endocrine systems underlies the pathogenesis of autoimmune rheumatic diseases. Most of the recent evidence derives from studies of sex hormones and pregnancy in women with systemic lupus. Other than an ameliorative effect of pregnancy, little is known about reproductive factors in relation to rheumatoid arthritis. To elucidate the relationship, a population-based retrospective study was undertaken. Included were 378 female residents of Olmsted County, Minnesota diagnosed with rheumatoid arthritis between 1950 and 1982 (cases) and 325 arthritis-free, married female controls matched to the 324 married cases on birth-year, age at first marriage, and duration of Olmsted County residency. Information of reproductive factors was extracted from the medical records system maintained by the Mayo Clinic.^ Cases had lower fertility rates compared with the female population of Minnesota (rate ratio = 0.86, 95% confidence interval (CI)= 0.80-0.92). Fertility was significantly reduced even prior to the onset of rheumatoid factor positive arthritis. Restricting the comparison to married Olmsted County residents did not alter the results. Further adjustments for time not at risk of conception using survival analysis and proportional hazards modeling only intensified the fertility reduction in the married cases compared with controls. Nulligravidity was more common among cases than controls (odds ratio = 3.16, CI = 1.61-6.20). Independent of fertility, pregnancy had a protective effect against rheumatoid arthritis (odds ratio = 0.31, CI = 0.11-0.89), which was dramatically reversed in the 12 months postpartum (odds ratio = 4.67, CI = 1.50-14.47). Cases were younger at menopause than controls (p $<$ 0.01).^ Small but statistically insignificant associations were observed between rheumatoid arthritis and the following factors: increased frequency of complaints to a physician of infertility; increased frequency of spontaneous abortion, premature birth, and congenital malformations following arthritis onset; and increased prevalence of menopause at arthritis onset. Cases did not differ from controls on age at menarche, duration of pregnancy, or birth weight.^ The findings provide further support for the involvement of the reproductive/endocrine systems in the pathogenesis of autoimmune rheumatic disease. The search for biological mechanisms should be intensified. ^

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PURPOSE Gender differences in paediatric patients with inflammatory bowel disease (IBD) are frequently reported as a secondary outcome and the results are divergent. To assess gender differences by analysing data collected within the Swiss IBD cohort study database since 2008, related to children with IBD, using the Montreal classification for a systematic approach. METHODS Data on gender, age, anthropometrics, disease location at diagnosis, disease behaviour, and therapy of 196 patients, 105 with Crohn's disease (CD) and 91 with ulcerative or indeterminate colitis (UC/IC) were retrieved and analysed. RESULTS THE CRUDE GENDER RATIO (MALE : female) of patients with CD diagnosed at <10 years of age was 2.57, the adjusted ratio was 2.42, and in patients with UC/IC it was 0.68 and 0.64 respectively. The non-adjusted gender ratio of patients diagnosed at ≥10 years was 1.58 for CD and 0.88 for UC/IC. Boys with UC/IC diagnosed <10 years of age had a longer diagnostic delay, and in girls diagnosed with UC/IC >10 years a more important use of azathioprine was observed. No other gender difference was found after analysis of age, disease location and behaviour at diagnosis, duration of disease, familial occurrence of IBD, prevalence of extra-intestinal manifestations, complications, and requirement for surgery. CONCLUSION CD in children <10 years affects predominantly boys with a sex ratio of 2.57; the impact of sex-hormones on the development of CD in pre-pubertal male patients should be investigated.

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The relationship between facial shape and attractiveness has been extensively studied, yet few studies have investigated the underlying biological factors of an attractive face. Many researchers have proposed a link between female attractiveness and sex hormones, but there is little empirical evidence in support this assumption. In the present study we investigated the relationship between circulating sex hormones and attractiveness. We created prototypes by separately averaging photographs of 15 women with high and low levels of testosterone, estradiol, and testosterone-to-estradiol ratio levels, respectively. An independent set of facial images was then shape transformed toward these prototypes. We paired the resulting images in such a way that one face depicted a female with high hormone level and the other a low hormone level. Fifty participants were asked to choose the more attractive face of each pair. We found that low testosterone-to-estradiol ratio and low testosterone were positively associated with female facial attractiveness. There was no preference for faces with high estradiol levels. In an additional experiment with 36 participants we confirmed that a low testosterone-to-estradiol ratio plays a larger role than low testosterone alone. These results provide empirical evidence that an attractive female face is shaped by interacting effects of testosterone and estradiol.

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BACKGROUND Low levels of testosterone in men and changes in retinal microvascular calibre are both associated with hypertension and cardiovascular disease risk. Sex hormones are also associated with blood flow in microvascular beds which might be a key intermediate mechanism in the development of hypertension. Whether a direct association between endogenous testosterone and retinal microvascular calibre exists is currently unknown. We aimed to determine whether testosterone is independently associated with ocular perfusion via a possible association with retinal vascular calibre or whether it plays only a secondary role via its effect on blood pressure in a bi-ethnic male cohort. PROBANDS AND METHODS A total of 72 black and 81 white men (28-68 years of age) from the follow-up phase of the Sympathetic activity and Ambulatory Blood Pressure in Africans (SABPA) study were included in this sub-study. Ambulatory pulse pressure and intraocular perfusion pressures were obtained, while metabolic variables and testosterone were measured from fasting venous blood samples. Retinal vascular calibre was quantified from digital photographs using standardised protocols. RESULTS The black men revealed a poorer cardiometabolic profile and higher pulsatile pressure (>50 mm Hg), intraocular pressure and diastolic ocular perfusion pressure than the white men (p≤0.05). Only in the white men was free testosterone positively associated with retinal calibre, i.e. arterio-venular ratio and central retinal arterial calibre and inversely with central retinal venular calibre. These associations were not found in the black men, independent of whether pulse pressure and ocular perfusion pressure were part of the model. CONCLUSIONS These results suggest an independent, protective effect of testosterone on the retinal vasculature where an apparent vasodilatory response in the retinal resistance microvessels was observed in white men.

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Membrane transporters are essential during pregnancy, being a core component of the exchange of nutrients, gases, and metabolic products between the mother and the developing fetus. Important compounds to be transported include vitamins and minerals, amino acids, glucose, as well as cholesterol. Cholesterol transport across the plasma membrane is mediated mainly by members of the ATP-binding cassette (ABC) transporter family. Cholesterol is present in every cell of the body, where it helps maintain the integrity of cell membranes and also plays an important role in cell signaling events. Cholesterol also acts as a precursor for the biosynthesis of steroids that include sex hormones, glucocorticoids, mineralcorticoids, as well as bile acids and oxysterols. Cholesterol transport is therefore crucial for a host of different physiological processes. The following chapter addresses the involvement and importance of ABC transporters in these different processes. The critical role that ABC transporters Play for a successful pregnancy outcome is highlighted by pathological processes that result malfunction of cholesterol transport during pregnancy. Avenues of future research are also described, which may help to further delineate the function and mechanism of action of ABC transporters.

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Evidence suggests that sex-based differences in immune function may predispose women to numerous hypersensitivity conditions such as Systemic lupus erythematosus (SLE), Hashimoto's thyroiditis and asthma. To date, the exact mechanisms of sexual dimorphism in immunity are not fully characterized but sex hormones such as 17-β estradiol (E2) and progesterone (PR) are believed to be involved. Since E2 and PR may modulate the production of critical regulatory cytokines, we sought to characterize their effects on the in vitro human type-1/type-2 cytokine balance. We hypothesized that E2 and/or PR vary cytokine production and influence costimulatory molecule expression and apoptosis. We first described the effect of E2 and/or PR on type-1 (IFN-γ and IL-12) and type-2 (IL-4 and IL-10) cytokine production by human peripheral blood mononuclear cells (PBMC) treated with various T-lymphocyte and monocyte stimuli. E2 and/or PR were each used at concentrations similar to those found at the maternal-fetal interface during pregnancy. At this dose, E2 increased IFN-γ and IL-12 production and PR decreased IFN-γ production and tended to increase IL-4 production. Furthermore, the combination of E2+PR decreased IL-12 production. This suggests that E2 shifts the type-1/type-2 cytokine balance towards a type-1 response and that PR and E2+PR shift the balance towards a type-2 response. Next, we used intracellular cytokine detection to demonstrate that E2 and/or PR are capable of altering cytokine production of CD3+ T-cells and the CD3+CD4+ and CD3+CD8+ subsets. In addition, we used the H9 T-lymphocyte cell line and the THP-1 monocyte cell line to show that E2 and/or PR can induce cytokine effects in both T-cells and monocytes independent of their interaction. Lastly, we determined the effect of E2 and/or PR on costimulatory molecule expression and apoptosis as potential mechanisms for the cytokine-induced alterations. E2 increased and PR decreased CD80 expression on THP-1 cells and PR and E2+PR decreased CD28 expression in PBMC and Jurkat cells. Furthermore, E2, PR and E2+PR increased Fas-mediated apoptosis in Jurkat cells and E2 increased FasL expression on THP-1 cells. Thus, E2 and/or PR may alter the cytokine balance by modulating the CD28/CD80 costimulatory pathway and apoptosis. ^