Long-term effects of transdermal and oral estrogens on serum lipids and lipoproteins in postmenopausal women

The transdermal and oral administration of estrogens for one year were compared with respect to the effects on lipid metabolism. Eighty-one postmenopausal women (1.5-3 years after menopause) were randomly divided into three groups. The first two groups received sequential estrogen treatment with either transdermal estradiol (Estraderm TTS, Ciba Geigy; 50 μg/day; 24 women) or 0.625 mg/day conjugated estrogens (Premarin, Wyeth; 20 subjects), respectively. In both groups medroxyprogesterone (10 mg/day per os) was added for 12 days of each cycle. Thirty-five subjects served as control group without therapy. No significant changes in the lipid profile was observed in control subjects after 1 year of follow-up. Serum triglycerides decreased significantly (-10.9 ± 26% S.D.; P < 0.05) in transdermal treated women, whereas it slightly rose in oral estrogen group. Comparable significant decreases in total and low density lipoprotein (LDL) cholesterol (mean range -6.5/-18.0%) were observed in women on estrogen replacement therapy. High density lipoprotein (HDL) cholesterol significantly diminished in transdermal estradiol group, but it rose slightly in the oral estrogen group. Thus the fraction of HDL cholesterol over LDL cholesterol did not change in the transdermal group whereas it significantly rose in subjects treated with oral estrogens. It remains to be established to what extent these differences on lipid metabolism are relevant for the prevention of cardiovascular diseases.     

人巨细胞病毒感染对小鼠脑组织同源框基因表达的影响

目的　研究小鼠脑组织同源框基因 (homeoboxgene ,Hox)的表达状态及人巨细胞病毒(humancytomegalovirus ,HCMV)感染对小鼠脑组织Hox基因表达的影响 ,以探讨HCMV致畸的分子机制。方法　昆明系小鼠 4 8只 ,随机分为 :实验对照组 (16只 )和病毒感染组 (32只 ) ,病毒感染为脑内注射。在感染后 7、15、30、6 0d分别以病理学方法观察病理损伤 ,以免疫组化方法检查HCMV LA(latean tigen) ,PCR检测小鼠脑组织中HCMV DNA。在建立HCMV脑部感染的小鼠模型基础上 ,用RT PCR测定Hox基因在病毒感染组和实验对照组小鼠脑组织中的表达 ,并用同位素标记的Hox寡核苷酸探针进行Northernblot检测相应的表达状况。结果　 (1)接种HCMVAD16 9株的小鼠脑组织发生了病理改变 ,免疫组化和PCR方法在神经细胞内查到了HCMV LA和DNA ;(2 )RT PCR和Northernblot发现 :对照组的小鼠脑组织表达Hoxa2、Hoxb1和Hoxb2 ,但不表达Hoxb5、Hoxb8;HCMV感染后 ,小鼠脑组织被诱导表达Hoxa1,与对照组比较差异有显著性意义 (P <0 .0 1) ,且于感染后的 15d达到高峰 ,而Hoxb1的表达下调 (P <0 .0 5 ) ;Hoxa2和Hoxb2无明显变化 ;Hoxb5和Hoxb8仍旧不表达。结论　HCMVAD16 9株可感染小鼠神经系统。HCMV感染可诱导小鼠神经系统发育基因Hox基因表达改变 ,这对     

Plasma concentrations of unconjugated and conjugated estrogens and gonadotrophins following application of various estrogen preparations after oophorectomy and in the menopause.

In 55 patients after oophorectomy and 20 women after natural menopause an oral estrogen replacement therapy was performed with estrone-sulfate, estradiol 17-valerate, estriol-succinate, a combination of micronized estradiol and estriol (Estrifam, Trisequens), and natural conjugated estrogens. In 4 patients a 3 mg estradiol per 5 g ointment substance was applied on the abdominal skin. The interindividual variations of estrogen increments during therapy were considerably high. Oral intake of 2 mg estriol-succinate daily was followed by a 500% increase of total (conjugated + unconjugated) estriol. Concentrations of unconjugated estrogens were not altered by this dosage. Following oral application of the other above mentioned preparations, prominent rises--especially of unconjugated estrogens in plasma--were noted. The concentration peaks occurred within 3--6 h after application. Unconjugated estradiol-17 beta in plasma was comparable with values of the follicular phase of a normal menstrual cycle, unconjugated estrone, however, was nonphysiologically high. Consequently, the E1/E2 ratio was greater than one whereas it is normally below one. 12 h after oral estrogen application, plasma estrogens dropped to almost initial values, so that a second medication seems to be necessary in order to guarantee an adequate supplementation over the course of the day. The hormone values determined in this study did not show significant differences between patients after a natural menopause and after oophorectomy. There was a positive correlation between rising estrogen levels and suppressed gonadotrophins during replacement therapy. The occurrence of climacteric symptoms did not exclusively depend on low estrogen and high gonadotrophin levels. Good tolerance of estrogen therapy with significantly elevated estrogen concentrations in plasma can be obtained transcutaneously in the form of estrogen ointments. Such therapy might simulate the physiological estrogen pattern even better than oral application does because of delayed and diluted steroid flow to the liver.     

雌激素受体抑制剂对小鼠囊胚形成的影响

目的观察雌激素受体（estrogen receptor,ER）抑制剂对昆明（Kunming,KM）小鼠体外囊胚形成的影响,为进一步探讨雌激素受体在小鼠囊胚形成中的作用和机制提供实验依据。方法以空白KSOM培养液为对照组,KSOM中添加浓度为1、2、3、4、5p~mol／L的ER仪抑制剂MPP,以及浓度为1、10、50、100μmol／L的ERB抑制剂PHTPP为实验组,收集KM小鼠8．细胞胚进行体外连续培养,计数各组发育至桑葚胚和囊胚两个阶段的数目,比较各组发育到囊胚的比率。结果添加浓度为1~mol／L、2Ixmol／L的MPP实验组囊胚发育率分别为86．36％、86．40％,与对照组（82．26％）相比无明显差别（P〉O．05）,而添加浓度为3μmol／L、4μmol／L、5μmol／L的MPP实验组囊胚发育率分别为46．58％、7．50％、0,发育率显著下降（P〈0．01）。添加浓度为1μmol／L、10μmol／L、50~mol／L的PHTPP实验组囊胚发育率分别为82．61％、87．04％、83．98％,与对照组（82．09％）比较没有明显差异（P〉O．05）,而添加高浓度（100μmol／L）的PHrrPP实验组囊胚发育率（51．39％）较明显下降。结论低浓度（5μmol／L）的ERo的抑制剂MPP可完全抑制KM小鼠8一细胞胚体外发育到囊胚,而50~mol／L的ERB抑制剂PHTPP对KM小鼠囊胚形成无明显影响,高浓度（100μmol／L）的PHTPP才可部分抑制囊胚形成。提示在小鼠囊胚形成中,ERα起着更为主要的作用。     

Modulation of human breast cancer cell adhesion by estrogens and antiestrogens

In order to study the effect of estrogens and antiestrogens on the adhesive properties of human breast cancer cells, the attachment on endothelial cells (EC), on subendothelial extracellular matrix (ECM) and on ECM components (collagen I and IV, laminin, fibronectin) of estrogen-dependent (MCF-7, ZR75-1) and estrogen-independent (BT-20) breast cancer cell lines was investigated. The cells were grown under conditions of controlled exposure to estrogen [17-estradiol (E₂)] and/or antiestrogens [tamoxifen (Tam) or 4-hydroxytamoxifen (OH-Tam]. Treatment by E₂ enhanced the ability of ZR75-1 cells to adhere to the various substrates, which contrasts with the observed absence of effects with the BT-20 cells. Similarly, Tarn or OH-Tam induced a reduction of the adhesion of ZR75-1 tumor cell, but not of BT-20 cells. This effect was reversed by competing concentrations of E₂. The effects on MCF-7 cell adhesion were similar to those described for ZR75-1 cells, but could not be reproducibly observed. Adhesion assays carried out with ZR75-1 cells grown in the absence or presence of phenol red, a pH indicator which behaves as a weak estrogen, led to a similar pattern of cell attachment. Conditioned media harvested from E₂-or Tamtreated ZR75-1 cells failed to induce any effect on adhesion of other ZR75-1 cells grown in E₂-deprived medium, suggesting that secretory activities are not required for the control of cell adhesiveness. The results suggest that estrogens and antiestrogens can control the adhesive behavior of breast tumor cells through their hormone responsive structures possibly by regulating expression of cell adhesion proteins and/or their cell surface receptors.     

The effect of estrogens and antiestrogens in a rat model for hot flush

The present studies evaluated the effect of estrogens and the selective estrogen receptor modulator (SERM) tamoxifen and raloxifene in a rat model for hot flush. In this model, ovariectomized rats were treated for 8 or 9 days either sc or po. Rats were dependent to morphine by implanting a morphine pellet (75 mg each) sc on days 3 and 5 of treatment. On the last day of treatment, a thermistor, connected to a data acquisition system, was placed on the tail of each animal and morphine addiction was withdrawn by naloxone injection (1.0 mg/kg, sc). Temperature measurements were taken for 1 h under ketamine (80 mg/kg, im) anesthesia. In general, vehicle treated rats showed a 5–6°C elevation of their tail skin temperature with the peak occurring about 15 min after naloxone injection. 17-Ethinyl estradiol (EE) was evaluated both sc and po using a broad range of doses. The IC₅₀ for inhibition of tail skin temperature rise was approximately 0.1 mg/kg, sc and 0.2 mg/kg, po. 17β-Estradiol and 17-estradiol were also active in this model whereas non-estrogenic steroids were inactive. Raloxifene and tamoxifen were tested for estrogen agonist and antagonist activity administered sc and po. Raloxifene did not demonstrate reproducible estrogen agonist activity at doses up to 10 mg/kg, whereas it demonstrated significant antagonistic activity at the 10 mg/kg dose regardless of the route of administration. Tamoxifen exhibited significant estrogen agonist activity at all doses tested (0.1–10.0 mg/kg) and was a significant antagonist of EE at the 1.0 mg/kg dose. Our results demonstrate the potential utility of this model to evaluate and discriminate among classes of compounds with varying degrees of estrogen agonist and antagonist activity.     

乳腺癌易感基因1的表达与乳腺癌亚型关系的实验研究

目的 探讨乳腺癌易基因1（BRCA1）的表达与乳腺癌分子亚型的关系.方法 运用免疫组化法检测乳腺癌组织中BRCA1的表达与雌二醇受体（ER）和人表皮生长因子受体-2（Her-2）的关系,分析BRCA1的表达在乳腺癌各亚型中的意义.结果 ER阳性和阴性时,BRCA1的阳性率分别为40.2％和60.0％,表明BRCA1表达与ER有关（P＜0.05）,与Her-2无关（P＞0.05）.在乳腺癌各分子亚型中,Luminal B型和Her-2过表达型的BRCA1阳性率（66.7％和70.0％）与Basal-like型的BRCA1阳性率（75.0％）差别无统计学意义（P＞0.05）;Luminal A型的BRCA1阳性率（23.7％）低于Basal-like型的BRCA1阳性率（75.0％）,差别具有统计学意义（P＜0.05）.结论 BRCA1在Luminal B型、Her-2过表达型和Basal-like型乳腺癌中表达较高,在Luminal A型乳腺癌中表达不高,提示BRCA1可成为治疗乳腺癌的重要靶点.     

Estrogen receptor (ER) and ER-related receptor expression in normal and atrophic human vagina

OBJECTIVES: The estrogen level decline in menopausal status is involved in physiological alterations of different human tissues including vaginal mucosa. In this study, we have evaluated the estrogen receptor (ER) and estrogen receptor-related receptor (ERR) expression in tissue samples of posterior vaginal wall obtained from pre- and post-menopausal women. METHODS: The nuclear receptor expression was determined by quantitative real-time PCR (qPCR). RESULTS: The qPCR results showed the presence of the three isoforms of the ERR family (ERRalpha, ERRbeta and ERRgamma) that were coexpressed with ERs in all vaginal tissue samples examined. The ERRalpha and ERRgamma mRNA levels decreased from normal vagina of the pre-menopausal women to atrophic vaginal tissue in post-menopausal women. This trend was also observed for the ERbeta subtype. CONCLUSIONS: The ERRs, such as ERs, are present in human vagina at the mRNA level and the cessation of ovarian estrogen secretion, that is the key event during the post-menopause, may be linked to ERbeta, ERRalpha and ERRgamma mRNA decline in human vaginal mucosa. These findings may provide a biological rationale for the clinical susceptibility of the post-menopausal vagina to local estrogen treatment.     

口服携带人IL-12、GM-CSF基因的减毒沙门菌抗肿瘤作用的试验

目的探讨以减毒沙门菌作为口服基因治疗载体的可行性.方法通过电转化法将真核表达载体pCMVhIL-12、pCMVhGM-CSF、EGFPN1导入减毒鼠伤寒沙门菌SL3261中,经由胃管喂给BALB/c和C57BL/6小鼠.6周后分别用4T1乳腺癌细胞和Lewis肺癌细胞进行攻击.通过流式细胞仪、共聚焦显微镜检测绿色荧光蛋白在小鼠各组织中的表达,通过PCR和ELISA法检测IL-12、GM-CSF基因的整合和表达情况.并考察肿瘤的受抑情况和小鼠的生存期.结果在小鼠的肝、脾、小肠、肾脏和肿瘤中可检测到绿色荧光蛋白的表达和相应细胞因子基因的整合.血清中相应的细胞因子水平较对照组明显升高(P<0.05),生存期远远超过对照组小鼠(P<0.05).结论减毒沙门菌可作为口服基因治疗载体,可能为肿瘤的治疗提供一条简便、安全、有效的途径.     

Nongenomic actions of estrogens: exciting opportunities for pharmacology

Estrogens, like other steroids, elicit a variety of rapid effects in many tissues in addition to their delayed action on gene expression in the cell nucleus. The rapid responses occur without participation of the genome, and are therefore termed nongenomic. Some of the estrogen induced effects acutely modulate vascular function and may contribute to the gender difference in cardiovascular susceptibility. While some actions may be mediated by novel, nonclassic receptors, the classic estrogen receptor has been shown to also act on signalling cascades. There are sparse examples for compounds structurally related to the endogenous hormone estradiol that bind to the estrogen receptor but may selectively elicit nongenomic responses. The further development of such selectively acting drugs holds much promise for better therapies with fewer side effects, e.g. for vascular malfunction, but also for estrogen-dependent cancer.     

Estrogen attenuates vascular expression of inflammation associated genes and adhesion of monocytes to endothelial cells

Objective Investigate effects of estrogen at gene expression and functional levels in vascular wall cells treated with bacterial lipopolysaccharide (LPS). Materials and methods Aortic segments from ovariectomized mice were treated with LPS for 24 h in the absence or presence of 17β-estradiol (E₂). Gene activity was determined by Affymetrix microarray analysis and real-time RT-PCR. Adhesion of [³H]-thymidine labelled human THP-1 monocytes to mouse bEnd.3 endothelial cells was determined by measuring radioactivity of DNA from co-culture homogenates. Results Analysis of global gene expression profiles revealed that 10 nM E₂ attenuates LPS-induced (10 ng/ml) expression of genes coding for well-known acute-phase proteins, such as alpha-trypsin inhibitor heavy chain 4, serum amyloid A3 and lipocalin 2. The E₂-induced down-regulation of these three genes observed by microarray was confirmed by realtime RT-PCR. Treatment with 500 ng/ml LPS increased adhesion of monocytes to endothelial cells more than two fold. Importantly, LPS-induced monocyte adhesion was fully prevented by 50 nM E₂. Conclusion Estrogen reduces expression of acute-phase protein genes and inhibits LPS-induced moncocyte adhesion to endothelial cells, suggesting that estrogen might have a vasculoprotective effect via this mechanism. Received 2 December 2005; returned for revision 28 February 2006; accepted by G. Wallace 27 March 2006     

Marked Individual Variation in Isoflavone Metabolism After a Soy Challenge Can Modulate the Skeletal Effect of Isoflavones in Premenopausal Women

Soy-isoflavones may act as estrogenic agonists or antagonists depending on the endogenous hormone status. These clinical effects can be exerted variably in individuals by the metabolic ability to produce a more potent metabolite than precursors. The objective of this randomized, double-blind, placebo-controlled study was to investigate the skeletal effect of isoflavones according to their metabolic variability in premenopausal women. Volunteers were randomly assigned to receive either soy-extract isoflavones (n=32) or lactose (n=21) once a day for three menstrual cycles. After intervention, the urinary excretions of isoflavones and their metabolites were significantly higher in the soy group than in the placebo group and showed a large inter-individual variation. Women in the soy group were divided into subgroups according to their ability to excrete more potent metabolites. Serum osteocalcin and urine deoxypyridinoline showed a tendency to increase after a challenge in equol high-excretors. Serum osteocalcin concentration in the genistein high-excretors increased significantly after a challenge (P=0.04) but did not increase in either the placebo or genistein low-excretors. An estrogenic antagonistic effect of isoflavones on bone turnover was observed in premenopausal women who are able to produce more potent metabolites.     

Conceptualizing the role of estrogens and serotonin in the development and maintenance of bulimia nervosa

Serotonergic dysregulation is thought to underlie much of the pathology in bulimia nervosa (BN). The purpose of this review is to expand the serotonergic model by incorporating specific and nonspecific contributions of estrogens to the development and maintenance of bulimic pathology in order to guide research from molecular genetics to novel therapeutics for BN. Special emphasis is given to the organizing theory of general brain arousal which allows for integration of specific and nonspecific effects of these systems on behavioral endpoints such as binge eating or purging as well as arousal states such as fear, novelty seeking, or sex. Regulation of the serotonergic system by estrogens is explored, and genetic, epigenetic, and environmental estrogen effects on bulimic pathology and risk factors are discussed. Genetic and neuroscientific research support this two-system conceptualization of BN with both contributions to the developmental and maintenance of the disorder. Implications of an estrogenic–serotonergic model of BN are discussed as well as guidelines and suggestions for future research and novel therapeutic targets.     

Effect of amitriptyline on the messenger RNA of thyroid hormone-responsive genes in rat cerebral tissue

To determine the molecular mechanisms of the potentiating effect of thyroid hormones (TH) on the therapeutic efficacy of tricyclic antidepressants (TCA), the expression of two known TH-responsive mRNAs was measured in control rats and rats treated with triiodothyronine (T3, 10 microg/100 g for 10 days), amitriptyline (10 mg/kg for 10 days), or combined T3 and amitriptyline. Northern blot analysis was carried out to measure the cerebral tissue content of a novel translational repressor (NAT-1) and another thyroid hormone-responsive (THR) mRNA. Rats treated with the combination of T3 and amitriptyline had significantly higher NAT-1 expression (2691.1+/-134.1 arbitrary units) than rats treated with T3 only (1688.5+/-77.8) or with amitriptyline only (1452.5+/-87.5) or the untreated control rats (731.3+/-23.0), P<0.01. Amitriptyline treatment did not alter the expression of THR mRNA or THR protein in either control or T3-treated rats. It is concluded that alterations in the expression of selective T3 responsive genes in cerebral tissue could be a mechanism of the known T3 potentiation of the therapeutic efficacy of TCA.     

Disentangling the molecular mechanisms of action of endogenous and environmental estrogens

The gonadal hormone 17-estradiol is involved in numerous cellular processes. In many cases, 17-estradiol actions are imitated by synthetic and natural chemicals in the environment. Their actions differ depending on the target tissue, the receptors involved and the molecular pathways activated. The plethora of estrogenic actions is triggered by different receptors and other specific structures that activate different signalling pathways. This amount of information may lead to a maze of effects triggered by endogenous and environmental estrogens that we intend to clarify in this review. Understanding the variety of estrogen receptors, their different locations and the signalling pathways activated by estrogenic ligands is fundamental for understanding the diversity of actions that estrogens have in different tissues and cells.     

雌激素对组织肾素-血管紧张素系统介导的相关疾病的影响

Estrogen improves the pathological changes of the local tissues and organs and recovers the tissue function by regulating the activity of tissue renin-angiotensin system (RAS) and the expression of RAS components in the local tissues such as heart, blood vessel, kidney, adrenal gland, brain and skeleton. Therefore, tissue RAS is the biological regulating targets of estrogen. Here we review the pathophysiological roles of estrogen in the local tissue RAS by analyzing and summarizing the recent researches.     

Effect of estrogen therapy, soy isoflavones, and the combination therapy on the submandibular gland of ovariectomized rats

The objective of this study was to evaluate the effect of estrogen deficiency, estrogen therapy, and soy isoflavones on the salivary glands in female rats. Ninety-six animals were ovariectomized, and 24 were sham-operated. Among the ovariectomized rats, 24 received 17β-estradiol; 24 received isoflavone extract; 24 received a combination therapy of both; and 24 received water as placebo. The submandibular glands were histomorphometrically analyzed. As a result, the ANOVA test revealed that the hormonal deficiency affected the acini and the ducts of ovariectomized rats, reducing their percentage compared to the sham group. All treatments caused an increase in ducts and acini compared to the placebo group. It was concluded that the estrogen deficiency may be related to salivary gland function due to a reduction in the quantity of salivary acini and ducts secondary to ovariectomy. The estrogen therapy, soy isoflavone therapy, and the combination of both are effective in reducing the effects of ovariectomy on the salivary glands.     

Influence of estrogen replacement therapy on cardiovascular responses to stress of healthy postmenopausal women

Two experiments were conducted to understand the influence of estrogen exposure on cardiovascular responses to acute stress measured by impedance cardiography. Study I compared stress responses of 29 postmenopausal women who used postmenopausal hormone replacement therapy (HRT) and 29 who did not use HRT. Women who did not use HRT had higher systolic blood pressure and pulse pressure responses to the tasks relative to HRT users. Study 2 compared stress responses of 38 healthy postmenopausal women not initially on HRT who were randomly assigned to transdermal estradiol or placebo treatment for 6-8 weeks. HRT assignment did not influence substantially women's cardiovascular responses to stress. Characteristics correlated with HRT use, not HRT itself, or differences in type, duration, and dosage may account for the discrepancy in results.