ER-alpha variants and the cardiovascular effects of hormone replacement therapy

Does genetic testing for ERα gene polymorphisms provide new possibilities of treatment for cognitive function disorders in postmenopausal women?

It is commonly considered that cognitive abilities decrease with age, especially with respect to processing and psychomotor speed. It is an interesting issue whether, apart from the ageing process, the undergoing of menopause itself deteriorates cognitive functions, compared to women at reproductive age. Hopes for improvement of cognitive functions were pinned on the use of menopausal hormone therapy. However, the results of studies concerning the effect of hormone replacement therapy on cognition proved to be contradictory. It seems that the essence of the problem is more complicated than only estrogen deficiency. It is suggested that estrogen receptor α (ERα) polymorphism may be responsible for the differences in the effect of estrogens on cognitive processes. The article presents current knowledge concerning the effect of estrogens on the central nervous system, especially the role of ERα polymorphism, with respect to foreseeing benefits from the use of exogenous estrogens for cognitive functions. At the present stage of research, ERα appears to be poorly specific; nevertheless, it may be an important instrument for the classification of peri- and post-menopausal patients in the group where therapy with the use of estrogens may bring about benefits in terms of prevention and treatment of cognitive disorders. It also seems necessary to conduct prophylactic, screening examination of cognitive functions in post-menopausal women, in order to identify those at risk of the development of dementia.

Estrogen receptor α gene polymorphisms and risk of Alzheimer's disease: evidence from a meta-analysis

Objective

Human estrogen receptor α (ESR1), a member of the nuclear receptor superfamily of ligand-activated transcription factors, is one of the key mediators of hormonal response in estrogen-sensitive tissues. Accumulating evidence has demonstrated that two of the most widely studied single-nucleotide polymorphisms in ESR1 – PvuII (T/C, rs223493) and Xbal (A/G, rs9340799) – are possibly associated with Alzheimer’s disease (AD). However, individual study results are still controversial.

Materials and methods

We searched PubMed, Embase, Web of Science, Science Direct, SpringerLink, and the Chinese National Knowledge Infrastructure databases for eligible studies assessing the association of ESR1 polymorphisms and AD risk (last search performed in November 2013). Thereafter, a meta-analysis of 13,192 subjects from 18 individual studies was conducted to evaluate the association between ESR1 polymorphisms and susceptibility to AD.

Results

The results indicated that a significant association was found between the ESR1 PvuII polymorphism and AD risk in Caucasian populations (CC + CT versus TT, odds ratio [OR] 1.14, 95% confidence interval [CI] 1.02–1.28, P=0.03; CT versus TT, OR 1.16, 95% CI 1.02–1.31, P=0.02), whereas no evidence of association was found in Asian populations. Nevertheless, we did not find any significant association between the ESR1 XbaI polymorphism and AD risk for any model in Caucasian and Asian populations (all P>0.05).

Conclusion

Based on this meta-analysis, we conclude that the ESR1 PvuII polymorphism might be a risk factor in AD development in Caucasian populations, not in Asian populations. Further confirmation is needed from better-designed and larger studies.

Association between single nucleotide polymorphisms of the estrogen receptor 1 and receptor activator of nuclear factor kappa B ligand genes and bone mineral density in postmenopausal Taiwanese

OBJECTIVE

To investigate the relationship between single nucleotide polymorphisms (SNPs) of the genes encoding the estrogen receptor 1 (ESR1) and the receptor activator of nuclear factor kappa B ligand (RANKL) and bone mineral density (BMD) in postmenopausal Taiwanese.

MATERIALS AND METHODS

Five ESR1 SNPs and three RANKL SNPs in 467 women were genotyped. Results of genotyping were correlated with BMD that had been adjusted for body mass index (BMI), age, and years after menopause.

RESULTS

Those with the ESR1 Crs1884054 allele were found to have a lower BMD at LS2-4/Lateral view (p = 0.005 and permutated p = 0.046), and those with the ESR1 haplotype Trs2234693-Ars922996 had a higher risk for low BMD also at LS2-4/Lat (OR = 1.8, 95% CI = 1.1-2.9). In addition, women without the RANKL haplotype Grs2148072-Crs2200287-Grs922996 had a higher risk for low BMD at LS1-4/AP (OR = 2.09, 95% CI = 1.21 ∼ 3.64). Stratification analyses revealed that those with ESR1 AArs1884054 and RANKL Ars2148072 (p = 0.032) or RANKL Trs2200287 (p = 0.007) had a lower BMD at LS1-4/AP.

CONCLUSION

Genotypes of these SNPs of ESR1 and RANKL may help us predict the osteoporosis risk in menopausal women.

Association of estrogen receptor genes and schizophrenia: a preliminary study

Gender differences in various clinical features of schizophrenia have been noted and estrogen has been regarded to play important roles. A few previous studies on the association between estrogen receptor (ER) genotypes and schizophrenia focused mainly on ER α gene but failed to report consistent results. The present study was designed to analyze the differences in the frequencies of both ERα and ERβ gene polymorphisms in subjects with schizophrenia compared to healthy controls among Korean population. Moreover, we investigate the association between different genotypes of ER genes and various clinical variables of schizophrenia. We observed that PvuII and XbaI polymorphisms of ERα gene showed significant differences between patients with schizophrenia and control groups (p=0.006). Among clinical variables, only the age of onset was related to RsaI genotype of ERβ gene (p=0.039). In conclusion, the present study suggests that ERα gene polymorphisms may be associated with the pathogenesis of schizophrenia and RsaI AA genotype of ERβ might have protective effect on age at onset of schizophrenia in Korean patients with schizophrenia.

Association between Estrogen Receptor Gene Polymorphisms and Depression in Post-Menopausal Women: A Preliminary Study

Post-menopausal women experience variable biological and psychological changes. The effect of reduced levels of estrogen can effect on post-menopausal depression. Estrogen triggers physiological responses by binding to the estrogen receptor (ER). Two subtypes of ER, ERa and ERb are now known. We investigated the significance of ERa and ERb polymorphisms and post-menopasal depression in this study. Forty three women with post-menopausal depression and 63 post-menopausal women without depression as normal controls were recruited. Polymerase chain reaction-restriction fragment length polymorphism method was used to investigate genotypes of ERa and ERb polymorphisms. Genotypes of PvuII and XbaI polymorphism of ERa receptor were significantly different in patients with post-menopausal depression comparing with controls. Genotypes of ERb did not show association with post-menopausal depression. Our study showed that ERa receptor polymorphism had an association with depression in post-menopausal women. It suggests that investigation of ER genes and their functions might be important for understanding pathophysilogical mechanism of post-menopausal depression.

Vascular actions of estrogens: functional implications

The impact of estrogen exposure in preventing or treating cardiovascular disease is controversial. But it is clear that estrogen has important effects on vascular physiology and pathophysiology, with potential therapeutic implications. Therefore, the goal of this review is to summarize, using an integrated approach, current knowledge of the vascular effects of estrogen, both in humans and in experimental animals. Aspects of estrogen synthesis and receptors, as well as general mechanisms of estrogenic action are reviewed with an emphasis on issues particularly relevant to the vascular system. Recent understanding of the impact of estrogen on mitochondrial function suggests that the longer lifespan of women compared with men may depend in part on the ability of estrogen to decrease production of reactive oxygen species in mitochondria. Mechanisms by which estrogen increases endothelial vasodilator function, promotes angiogenesis, and modulates autonomic function are summarized. Key aspects of the relevant pathophysiology of inflammation, atherosclerosis, stroke, migraine, and thrombosis are reviewed concerning current knowledge of estrogenic effects. A number of emerging concepts are addressed throughout. These include the importance of estrogenic formulation and route of administration and the impact of genetic polymorphisms, either in estrogen receptors or in enzymes responsible for estrogen metabolism, on responsiveness to hormone treatment. The importance of local metabolism of estrogenic precursors and the impact of timing for initiation of treatment and its duration are also considered. Although consensus opinions are emphasized, controversial views are presented to stimulate future research.

Ovulatory response to treatment of polycystic ovary syndrome is associated with a polymorphism in the STK11 gene

CONTEXT

Clomiphene and insulin sensitizers such as metformin are used to induce ovulation in polycystic ovary syndrome (PCOS), but the ovulatory response is variable, and the causes of this variation are poorly understood.

OBJECTIVE

Our objective was to identify predictive genetic polymorphisms and other determinants of ovulatory response.

DESIGN

This was a substudy of a multicenter randomized clinical trial.

SETTING

This study was performed at academic medical centers and their affiliates.

PARTICIPANTS

A total of 312 women with PCOS were included in the study.

MAIN OUTCOME MEASURES

Historical, biometric, biochemical, and genetic parameters were performed.

RESULTS

We found that the C allele of a single nucleotide polymorphism in the STK11 gene (expressed in liver; also known as LKB1) was associated with a significantly decreased chance of ovulation in PCOS women treated with metformin. In an analysis of ovulation per cycle, the adjusted odds ratio (OR) comparing the C/C genotype to the G/G genotype was 0.30 [95% confidence interval (CI) 0.14, 0.66], and the OR for the C/G genotype vs. the G/G genotype was also 0.30 (95% CI 0.14, 0.66). In an analysis of metformin-treated subjects, we found that the percentage of women who ovulated increased with the number of G alleles present: 48% (10 of 21) of C/C women, 67% (32 of 48) of C/G women, and 79% (15 of 19) of G/G women ovulated. We also found that increased frequency of ovulation was associated with lower body mass index (BMI) [adjusted OR of 2.36 (95% CI 1.65, 3.36) and 2.05 (95% CI 1.46, 2.88), respectively, for comparisons of BMI less than 30 vs. BMI equal to or more than 35, BMI 30-34 vs. BMI equal to or more than 35, in the analysis of ovulation per cycle], a lower free androgen index (FAI) [adjusted OR of 1.59 (95% CI 1.17, 2.18) for FAI<10 vs. FAI>or=10], and a shorter duration of attempting conception [adjusted OR of 1.63 (95% CI 1.20, 2.21) for<1.5 vs.>or=1.5 yr].

CONCLUSIONS

We have demonstrated that a polymorphism in STK11, a kinase gene expressed in liver and implicated in metformin action, is associated with ovulatory response to treatment with metformin alone in a prospective randomized trial. The interaction with the effects of changes in modifiable factors (e.g. BMI or FAI) requires further study.

Estrogen receptor alpha gene polymorphisms and first-ever intracerebral hemorrhage

BACKGROUND

Signaling through estrogen receptor alpha (ER alpha) regulates vasodilatation and atherogenesis. Since hypertension and atherosclerosis are major mechanisms in stroke development, we hypothesized that genetic variants of the ER alpha gene (ESR1) are determinants of future ischemic stroke or intracerebral hemorrhage (ICH).

METHODS

In a population-based prospective nested case-control study, the relationships between ESR1 polymorphisms (c.454-397T>C and c.454-351A>G) and ischemic stroke and ICH were examined in univariate and multivariate models using conditional logistic regression, which included established risk factors.Definitive first-ever stroke events (n = 388), including ischemic stroke (n = 320), ICH (n = 61), and unspecified stroke (n = 7) cases, and controls without cardiovascular disease (n = 773), matched for age, sex, and geographical region were included.

RESULTS

Carriers of the c.454-397T/T genotype had a significantly (p = 0.017) increased risk of ICH (OR 2.31, 95% CI 1.16-4.60) in a univariate analysis. This association persisted (OR 3.94, 95% CI 1.54-10.03), after adjustment for stroke risk determinants. Carriers of c.454-397T/T or c.454-397T/C genotypes had significantly (p = 0.002 and p = 0.004, respectively) higher mean systolic blood pressure (SBP), than carriers of c.454-397C/C, and a similar relationship was observed for diastolic blood pressure (DBP). The combinations of c.454-397T/T genotype and hypertension (OR 21.46, 95% CI 5.20-88.51), or high SBP (OR 18.17, 95% CI 4.91-67.31) or DBP (OR 11.94, 95% CI 3.75-38.03), were strongly associated with increased risk of ICH.

CONCLUSIONS

In this population,the c.454-397T/T genotype associates with first-ever ICH, particularly in combination with hypertension. This implies that alterations in ER alpha-mediated signaling may be involved in the pathophysiology of this disease, with a putative impact on primary prevention.

Genetics and pharmacogenetics of estrogen response

Estrogens are a steroid hormone group distributed widely in animals and human beings. Estrogens diffuse across cell phospholipidic membranes and interact with estrogen receptors. Their highest concentration is found in target tissues with reproductive function (breast, ovary, vagina and uterus). High estrogen levels are usually associated with tumor onset and progression, while loss of estrogen or its receptor(s) contributes to development and/or progression of various diseases (osteoporosis, neurodegenerative disease and cardiovascular disease). Despite the numerous efforts to highlight estrogen's mechanism of action, recent discoveries showed an unexpected degree of complexity of estrogenic response.

Steroid hormone receptor gene polymorphisms and osteoporosis: a pharmacogenomic review

Osteoporosis is a common skeletal disorder with a strong genetic component. In recent years, significant progress has been made in understanding the genetic basis of osteoporosis. Given the biological significance of signalling through steroid hormone receptors, bone biology and calcium homeostasis, alleles of steroid hormone receptor genes have been postulated to contribute to the well-documented genetic predisposition to osteoporosis; and in different studies, these alleles have been associated with variation in bone mass and fracture risk. Even though results are still conflicting and the molecular mechanisms by which these polymorphisms influence receptor activity remain, in part, to be investigated, an additional important issue is represented by potential pharmacogenomic (the investigation of variations of DNA or RNA characteristics as related to drug response) or pharmacogenetic (the influence of variations of DNA sequence on drug response) implications. In fact, steroid hormone receptors actually mediate the action of several compounds known to positively or negatively affect bone homeostasis, such as vitamin D, estrogen and glucocorticoids. This review analyses major pharmacogenetic studies of polymorphisms in steroid hormone receptor genes.

Investigation of the estrogen receptor-alpha gene with type 2 diabetes and/or nephropathy in African-American and European-American populations

The estrogen receptor-alpha gene (ESR1) was selected as a positional candidate under a type 2 diabetes linkage peak at 6q24-27. A total of 42 ESR1 single nucleotide polymorphisms (SNPs) were genotyped in 380 African-American type 2 diabetic case subjects with end-stage renal disease (ESRD) and 276 African-American control subjects. A total of 22 ancestry informative markers were also genotyped, and the program Admixmap was used to adjust allelic and haplotypic association tests for individual estimates of admixture. The most significant association with type 2 diabetes-ESRD was with rs1033182 in intron 2 (P = 0.013, admixture-adjusted P(a) = 0.021). Genotyping 17 SNPs across a region of ESR1 intron 1-intron 2 in an expanded population of 851 case and 635 control subjects supported association with rs1033182 (P = 0.004, P(a) = 0.027) and with an independent six-SNP haplotype of high linkage disequilibrium spanning 6.4 kb (P < 0.0001, P(a) < 0.0001). The same 17 ESR1 SNPs were genotyped in 300 European-American type 2 diabetes-ESRD case subjects and 310 European-American control subjects. Two intron 2 SNPs, rs2431260 (P = 0.015) and rs1709183 (P = 0.019), and a four-SNP haplotype containing these SNPs (P = 0.033) were associated with type 2 diabetes and/or ESRD. Results suggest that intron 1 and intron 2 of the ESR1 gene may contain functionally important regions related to type 2 diabetes or ESRD risk.

Spontaneous airway hyperresponsiveness in estrogen receptor-alpha-deficient mice

RATIONALE

Airway hyperresponsiveness is a critical feature of asthma. Substantial epidemiologic evidence supports a role for female sex hormones in modulating lung function and airway hyperresponsiveness in humans.

OBJECTIVES

To examine the role of estrogen receptors in modulating lung function and airway responsiveness using estrogen receptor-deficient mice.

METHODS

Lung function was assessed by a combination of whole-body barometric plethysmography, invasive measurement of airway resistance, and isometric force measurements in isolated bronchial rings. M2 muscarinic receptor expression was assessed by Western blotting, and function was assessed by electrical field stimulation of tracheas in the presence/absence of gallamine. Allergic airway disease was examined after ovalbumin sensitization and exposure.

MEASUREMENTS AND MAIN RESULTS

Estrogen receptor-alpha knockout mice exhibit a variety of lung function abnormalities and have enhanced airway responsiveness to inhaled methacholine and serotonin under basal conditions. This is associated with reduced M2 muscarinic receptor expression and function in the lungs. Absence of estrogen receptor-alpha also leads to increased airway responsiveness without increased inflammation after allergen sensitization and challenge.

CONCLUSIONS

These data suggest that estrogen receptor-alpha is a critical regulator of airway hyperresponsiveness in mice.

Estrogen receptor alpha and APOEepsilon4 polymorphisms interact to increase risk for sporadic AD in Italian females

Alzheimer's disease (AD) is a progressive neurodegenerative disease that affects both sexes, with a higher prevalence in women. Declining estrogen levels after menopause may render estrogen target neurons in the brain more susceptible to age or disease-related processes such as AD. To investigate the role of two single nucleotide polymorphisms in the first intron of the ER-alpha gene, denominated PvuII and XbaI, and their interaction with the known AD susceptibility gene APOE, we examined 131 patients with sporadic AD and 109 healthy control subjects. In multinomial logistic regression analysis, a significantly increased risk of sporadic AD because of interaction between the ER-alpha p allele and APOE epsilon4 allele was observed in women, taking subjects who had neither the p allele nor epsilon4 as reference [odds ratio (OR) 7.24; 95% CI, 2.22-23.60]. For women carrying the ER-alpha x allele together with APOE epsilon4, the risk of sporadic AD was similarly elevated (OR 8.33; 95% CI, 1.73-40.06). The data suggest that the p and x alleles of polymorphic ER-alpha gene interact synergistically with the APOE epsilon4 allele to increase the risk of AD in women but not in men in this Italian cohort.

Therapeutic implications of the gender-specific aspects of cardiovascular disease

The manifestations of cardiovascular diseases differ between men and women, as do outcomes after therapeutic interventions. It is important that those involved in drug discovery and development, as well as disease treatment, are aware of these differences because such variations are likely to have an increasing role in therapeutic decisions in the future. Here, I review gender differences in the most frequent cardiovascular diseases and their underlying sex-dependent molecular pathophysiology, and discuss gender-specific effects of current cardiovascular drugs and the implications for novel strategies for drug development.

Effect of Hormone Replacement Therapy on Plasma Lipoproteins and Apolipoproteins, Endothelial Function and Myocardial Perfusion in Postmenopausal Women with Estrogen Receptor-α IVS1–397 C/C Genotype and Established Coronary Artery Disease

Effect of hormone replacement (HRT) therapy on plasma lipoproteins and apolipoproteins, endothelial function and myocardial perfusion in postmenopausal women with estrogen receptor-alpha (ER-alpha) IVS1-397 C/C genotype and established coronary artery disease.

BACKGROUND/AIMS

Associations between various ER-alpha polymorphisms and clinical phenotypes have been studied, including lipid levels and coronary atherosclerosis. We studied 48 postmenopausal women to determine the effect of ER-alpha IVS1-397 polymorphism on the response to treatment with HRT.

METHODS

The study had a randomized, double-blind, placebo-controlled and crossover design. Patients were divided into two groups according to ER-alpha IVS1-397 polymorphism: CC genotype (n = 9); CT or TT genotype (n = 39). HRT was given continuously for 4 weeks, with 4-week washout periods between the treatment periods. Brachial artery Doppler and Tl-201 scintigraphy were performed at the end of each treatment period.

RESULTS

HRT lowered total cholesterol, LDL-c and Apo-B levels from baseline values (all p < 0.05) and to a similar degree in CC and CT/TT genotype patients. HRT increased estradiol, HDL-c and Apo A-1 levels relative to baseline values, but to a greater degree in CC patients (p = 0.04, 0.05 and 0.04 by ANOVA, respectively). HRT increased peak forearm blood flow, brachial artery diameter during reactive hyperemia and endothelium-dependent dilation in both groups, but to a greater degree in CC patients (p = 0.03, 0.03 and 0.04 by ANOVA, respectively). Summed stress and rest scores were also more markedly reduced in CC patients (p = 0.04 and 0.05, respectively). The increase in estradiol levels was strongly correlated with the improvement in endothelium-dependent dilation (r = 0.66, p < 0.01), which in turn showed negative correlation with summed stress (r = -0.62, p < 0.01) and rest scores (r = -0.52, p < 0.05) in the CC genotype group.

CONCLUSION

These data suggest that the improvement in endothelium-dependent dilation and the reduction in perfusion abnormalities by increasing estradiol levels with HRT in postmenopausal women with coronary artery disease may differ with respect to different genotypes, the effect being more prominent in those patients with ER-alpha IVS1-397 CC genotype.

Genotype distribution of estrogen receptor-alpha, catechol-O-methyltransferase, and cytochrome P450 17 gene polymorphisms in Caucasian women with uterine leiomyomas

OBJECTIVE

To evaluate the association between the presence of uterine leiomyomas and three functional single nucleotide polymorphisms (SNPs) of the estrogen receptor alpha (ESR1), catechol-O-methyltransferase (COMT), and cytochrom P450 17 (CYP17A) genes, which have been described to modify the estrogen metabolism.

DESIGN

Prospective case control study.

SETTING

Academic research institution.

PATIENT(S)

One hundred thirty women with clinically and surgically diagnosed uterine leiomyomas and 139 population controls.

INTERVENTION(S)

Peripheral venous puncture.

MAIN OUTCOME MEASURE(S)

Polymerase chain reaction and pyrosequencing were performed to genotype women with respect to the ESR1 IVS1-397 T/C (PvuII), COMT G158A, and the CYP17A 34T-->C SNPs.

RESULT(S)

Comparing women with uterine leiomyomas and controls, no statistically significant differences with respect to allele frequency and genotype distribution were ascertained for ESR1 IVS 1-397 T/C (PvuII) (P=0.9 and P=0.6, respectively), COMT G158A (P=0.3 and P=0.6, respectively), and CYP17A 34T-->C (P=0.1 and P=0.5, respectively). When all two-way interactions of investigated SNPs were ascertained, no significant interactions were observed. In a multivariate model, no SNP was significantly associated with leiomyomas.

CONCLUSION(S)

Carriage of the ESR1 IVS1-397 T/C (PvuII), COMT G158A, and the CYP17A 34T-->C SNPs is not associated with the susceptibility to uterine leiomyoma in a Caucasian population.

Oestrogen receptor {alpha} gene polymorphisms in systemic lupus erythematosus

OBJECTIVE

To analyse associations of two oestrogen receptor alpha (ORalpha) gene polymorphisms in 260 patients with SLE from northern Sweden. The two polymorphisms, PvuII T/C and the XbaI A/G, are located in the first intron of the ORalpha gene.

METHODS

All patients fulfilling at least four of the ACR criteria for SLE were consecutively recruited during one year. The SLEDAI score and SLICC damage index were recorded. 670 individuals from the same geographical area served as controls. DNA from the patients and controls was extracted and genotyped using the 5' nuclease assay with an ABI PRISM 7900HT instrument. The genotype/phenotype relationships were calculated using SPSS.

RESULTS

The unusual PvuII C allele was associated with malar rash and the unusual XbaI G allele with photosensitivity (p = 0.001, OR = 2.53, 95% CI = 1.43 to 4.47 and p = 0.007, OR = 2.12, 95% CI = 1.22 to 3.66, respectively). The common XbaI AA genotype was associated with serositis (p = 0.013, OR = 1.92, 95% CI = 1.15 to 3.22). Based on the SLICC damage index associations of the common TT genotype and AA genotype with cognitive impairment were identified (p = 0.018, OR = 2.47, 95% CI = 1.17 to 5.25 and p = 0.018, OR = 2.75, 95% CI = 1.19 to 6.38 respectively). There was also an association of the XbaI AA genotype with the angina/coronary artery bypass variable (p = 0.042, OR = 2.58, 95% CI = 1.03 to 6.43). Of the variables describing disease severity and duration it was found that carriers of the unusual PvuII C allele showed a later onset of SLE (p = 0.02) and carriers of the unusual XbaI G allele a lower SLICC damage index.

CONCLUSIONS

The unusual PvuII C and XbaI G alleles were associated with a milder form of SLE characterised by skin manifestations, later onset, and less organ damage.

Combined estrogen receptor α and estrogen receptor β genotypes influence the age of menarche

BACKGROUND

Age at menarche has a strong genetic influence. We reported recently an association between the XbaI (351A-->C)and PvuII (397T-->C) polymorphisms of the estrogen receptor (ER)alpha gene with the age of menarche in Greek adolescents. In the present study, we examined whether ERbeta genotypes alone, or in combination with ERalpha genotypes, may also influence onset of menarche.

METHODS

We performed genotyping for the single nucleotide polymorphisms 1730A-->G and 1082G-->A of the ERbeta gene and examined their association with the age of menarche in the same cohort of 145 Greek girls. We then looked for a possible effect of combined ERalpha and beta genotypes on the age of menarche.

RESULTS

Menarche occurred 7 months later in girls with the AA genotype of the 1730A-->G polymorphism than in girls with the AG genotype (mean +/- SD: 13.23 +/- 1.24 versus 12.66 +/- 1.26 years, respectively; P = 0.005). The 1082G-->A polymorphism was not detected in any of the girls examined. A significant effect of combined ERalpha and beta genotypes was also apparent. Menarche occurred 11 months later in girls bearing the AA/TT,AA (ERalpha, ERbeta) genotypes compared with girls with the CC/CC,AG genotype (13.30 +/- 1.27 nersus 12.41 +/- 1.28 years; P = 0.042). The difference remained significant after adjusting for body mass index (P = 0.034).

CONCLUSION

Combined ERalpha and ERbeta polymorphisms may influence the age of menarche.

Estrogen receptor-alpha thymidine and adenine repeat polymorphism and endothelial fibrinolytic regulation in postmenopausal women

OBJECTIVE

We hypothesized that the capacity of the endothelium to release tissue-type plasminogen activator is blunted in postmenopausal women with long (TA)(n) repeat alleles (> or = 18 repeats).

STUDY DESIGN

Forty-two healthy postmenopausal women were studied: 10 women with short allele genotypes (both alleles, <18 repeats; age, 59 +/- 2 years), 8 women with long allele genotypes (both alleles, > or = 18 repeats; age, 59 +/- 3 years), and 24 women with mixed allele genotypes (1 short and 1 long allele; age, 56 +/- 1 years). Net endothelial tissue-type plasminogen activator release was determined in response to intra-arterial bradykinin and sodium nitroprusside.

RESULTS

Tissue-type plasminogen activator release in response to bradykinin was highest in homozygotes for the short allele. The total amount of tissue-type plasminogen activator antigen that was released was significantly higher (>55%) in the short (452 +/- 68 ng/100 mL tissue) compared with the mixed (248 +/- 27 ng/100 mL tissue) and long allele (290 +/- 53 ng/100 mL tissue) groups.

CONCLUSION

Our results demonstrate that the long (TA)n dinucleotide repeat allele is associated with blunted endothelial tissue-type plasminogen activator release in healthy postmenopausal women.

Resveratrol and estradiol rapidly activate MAPK signaling through estrogen receptors alpha and beta in endothelial cells

Vascular endothelial cells (EC) are an important target of estrogen action through both the classical genomic (i.e. nuclear-initiated) activities of estrogen receptors alpha and beta (ERalpha and ERbeta) and the rapid "non-genomic" (i.e. membrane-initiated) activation of ER that stimulates intracellular phosphorylation pathways. We tested the hypothesis that the red wine polyphenol trans-resveratrol activates MAPK signaling via rapid ER activation in bovine aortic EC, human umbilical vein EC, and human microvascular EC. We report that bovine aortic EC, human umbilical vein EC, and human microvascular EC express ERalpha and ERbeta. We demonstrate that resveratrol and estradiol (E(2)) rapidly activated MAPK in a MEK-1, Src, matrix metalloproteinase, and epidermal growth factor receptor-dependent manner. Importantly, resveratrol activated MAPK and endothelial nitric-oxide synthase (eNOS) at nm concentrations (i.e. an order of magnitude less than that required for ER genomic activity) and concentrations possibly achieved transiently in serum following oral red wine consumption. Co-treatment with ER antagonists ICI 182,780 or 4-hydroxytamoxifen blocked resveratrol- or E(2)-induced MAPK and eNOS activation, indicating ER dependence. We demonstrate for the first time that ERalpha-and ERbeta-selective agonists propylpyrazole triol and diarylpropionitrile, respectively, stimulate MAPK and eNOS activity. A red but not a white wine extract also activated MAPK, and activity was directly correlated with the resveratrol concentration. These data suggest that ER may play a role in the rapid effects of resveratrol in EC and that some of the atheroprotective effects of resveratrol may be mediated through rapid activation of ER signaling in EC.

Estrogen receptor 2 and progesterone receptor gene polymorphisms and lipid levels in women with different hormonal status

Sex steroid hormones have multiple effects on lipid metabolism. We investigated the association between two common single nucleotide polymorphisms of the estrogen receptor 2 gene (ESR2), 1082G>A and 1730A>G, and PROGINS polymorphism of the progesterone receptor gene (PGR) with lipoprotein levels in a cross-sectional study with 472 women of European descent. The women were classified into three subgroups according to hormonal status, premenopausal women (n=187; mean age=34+/-9.7 years), postmenopausal women exposed to hormone replacement therapy (HRT) (n=118; 56+/-6.7 years) and postmenopausal women unexposed to HRT (n=167; 58+/-9.8 years). The premenopausal and postmenopausal women exposed to HRT, both carriers of G/A genotype, exhibited LDL-C (P=0.027 and 0.001, respectively) and T-chol levels (P=0.035 and 0.001, respectively) lower than carriers of G/G genotype. This association was not observed in postmenopausal women unexposed to HRT. These results suggest that ESR2 1082G>A genotype may influence LDL-C levels in women with abundant estrogen levels, due to either endogenous or exogenous sources.

Hormone replacement therapy update: who should we be prescribing this to now?

PURPOSE OF REVIEW

To summarize results from the Women's Health Initiative trial and other recent randomized placebo-controlled trials of hormone replacement therapy, which fundamentally changed our understanding of its risks and benefits.

RECENT FINDINGS

The Women's Health Initiative study for the first time provided evidence of harmful effects of hormone replacement therapy on the cardiovascular system and also confirmed significantly increased risk of breast cancer which was previously documented in a metaanalysis. Most recent studies indicate a particularly harmful effect of combined estrogen/progestin regimens in terms of increased breast cancer risk.

SUMMARY

The effects of hormone replacement therapy on coronary heart disease, stroke, venous thromboembolism, breast cancer, gallbladder, diabetes, cognitive function, health-related quality of life, colorectal cancer, osteoporosis and menopausal symptoms are discussed briefly. The emphasis is on providing concise clinical guidelines for hormone replacement therapy use in new circumstances. We also discuss some alternative therapeutic modalities for women who have menopausal symptoms, but contraindications for hormone replacement therapy.