首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
2.
Recently, the effects of extremely low-frequency electromagnetic fields (ELF EMF) on biological systems have been extensively investigated. In this report, the influence of ELF EMF on olfactory bulb (OB) estrogen receptor-α (ERα) mRNA and -β (ERβ) mRNA expression was studied by RT-PCR in adult female and male rats. Results reveal for the first time that ELF EMF exerted a biphasic effect on female OB ERβ mRNA gene expression, which increased during diestrous and decreased during estrous. We did not observe any influence of ELF EMF on female OB ERα mRNA expression. Our data demonstrate a fluctuating pattern of ER-α and -β mRNA expression in the female OB throughout the phases of the estrous cycle in non-ELF EMF-exposed animals. Thus the highest ERα expression was observed in diestrous and the lowest in proestrous. The pattern of ERβ mRNA was less variable, the lowest expression was observed in diestrous. ER-α mRNA and -β mRNA expression level in the male OB did not exhibit any variation either in ELF EMF-exposed or non-ELF EMF-exposed animals. In summary, ELF EMF modulate ERβ gene expression in the OB of female adult rats but not in males.  相似文献   

3.
Endometrial carcinoma (EC), an estrogen-dependent gynecological malignancy, is prevalent worldwide. Estrogen receptor α (ERα) and estrogen receptor β (ERβ) are two main estrogen receptor isoforms, which mediate estrogen-induced proliferation in EC. However, the dynamic changes of ERα and ERβ subtype expression and their functions on proliferation in EC remain elusive. In this study, we aimed to investigate the expression of ERα and ERβ in para-tumor eutopic endometrium, endometrial atypical hyperplasia and EC by immunohistochemistry and then analyse their clinical significance. Subsequently, Ishikawa cells with ERα or ERβ knockdown by lentivirus transfection were used to explore the relationship between ERα/ERβ and cell proliferation, and preliminarily evaluate whether metformin’s inhibitory effect on estrogen-induced cell proliferation was mediated by ERα and ERβ. We found that the expression of ERα and ERβ were markedly changed in endometrial hyperplasia and EC compared with that in para-tumor eutopic endometrium and exhibited different expression trends. Through further analysis, we discovered that ERα presented higher expression in endometrial atypical hyperplasia and early stage of EC than that in para-tumor eutopic endometrium, while the expression of ERβ gradually decreased from para-tumor eutopic endometrium to EC. Additionally, the cell cycle-related protein, CyclinD1 was gradually increased but p21 decreased. Furthermore, knockdown of ERα and ERβ severally in Ishikawa cells either inhibited or promoted estrogen-induced cell proliferation through regulating CyclinD1 and p21 expression. Meanwhile, the inhibitory effect of metformin on estrogen-induced cell proliferation was respectively blunted or partly reversed by knockdown of ERα or ERβ. Altogether, ERα and ERβ have different expression patterns in the progression of EC either facilitating or suppressing cell proliferation through regulating the expression of CyclinD1 and p21 in EC cells, and may also mediate the inhibitory effect of metformin on estrogen-induced EC cells proliferation.  相似文献   

4.
目的 研究雌激素受体(ER)不同亚型在子宫内膜异位症的在位和异位内膜中的表达,以寻找其在不同病灶中的分布规律,探讨子宫内膜异位症的发病机制.方法 收集解放军总医院2004年1月-2006年12月行手术治疗的卵巢子宫内膜异位症石蜡标本,包括卵巢子宫内膜异位囊肿60例及其在位内膜60例(增生期各30例、分泌期各30例)以及正常子宫内膜30例(增生期和分泌期各15例).采用免疫组织化学(EnVision)方法检测上述组织中ERα和ERβ的表达.染色结果半定量化,并分析比较各种组织间的表达差异.结果 各组中,ERα和ERβ在腺上皮的表达与它们在间质细胞中的表达呈正相关.ERα蛋白在不同部位的表达:在位内膜ERα的表达(腺上皮和间质细胞阳性率分别为73.3%和76.7%)高于卵巢子宫内膜异位囊肿(腺上皮和问质细胞阳性率分别为43.4%和46.7%)和正常内膜的表达(腺上皮和间质细胞阳性率分别为56.7%和50.0%),均P<0.05.ERβ蛋白在不同部位的表达:卵巢子宫内膜异位囊肿(腺上皮和间质细胞阳性率分别为90.0%和76.7%)高于在位子宫内膜的表达(腺上皮和间质细胞阳性率分别为68.0%和63.3%),后者又高于正常子宫内膜(腺上皮和间质细胞阳性率分别为36.7%和26.7%),P均<0.05.在位内膜的ERα和ERβ蛋白表达在增殖期均高于分泌期,P均<0.05;异位内膜增殖期和分泌期的表达差异无统计学意义.ERα和ERβ蛋白在不同部位表达的比较:在正常内膜中ERα的表达略高于ERβ,但差异无统计学意义,P>0.05;卵巢子宫内膜异位囊肿中ERβ的表达高于ERα,P<0.05;而在位内膜中两种亚型表达差异无统计学意义.结论 子宫内膜异位症患者在位子宫内膜及异位内膜均有ERα和ERβ的表达,但与正常子宫内膜相比,在卵巢子宫内膜异位囊肿中ERβ表达占优势,而ERα表达受限.ERα和ERβ在不同组织中的分布及表达水平与子宫内膜异位症的发生和发展有着密切关系.  相似文献   

5.
In order to investigate the roles of ER subtypes in the estrogen-induced lupus phenotype, ERα-deficient (ERα−/−) and wild-type mice (WT) were injected monthly with estradiol (E-2) starting at 8 weeks. In WT mice, E-2 treatment induced a lupus phenotype, with accelerated death and increased kidney damage, as well as Th2-type serum cytokine and autoantibody production. In contrast, only minimal changes were observed in ERα−/− mice after E-2 treatment. In a separate study, we found that in immune cells of autoimmune-prone SNF1 and non-autoimmune DBF1 mice, both ERα and ERβ were differentially expressed and modulated by E-2. In SNF1 mice, there were more CD4+ and CD8+ T cells constitutively expressing ERα, and the percentages of ERα+ dendritic cells and macrophages were increased after E-2 exposure compared to DBF1 mice. Taken together, these observations strongly suggest a role for ERα in E-2-induced development of the lupus phenotype.  相似文献   

6.
Within the catecholaminergic systems, there are contradictory findings regarding ability of estradiol to regulate expression of genes related to catecholamine biosynthesis. Several parameters important for effects of estradiol on the catecholamine (CA) related enzyme gene expression were examined in two CA regions. Ovariectomized (OVX) female rats were given prolonged estradiol treatments, either in a pulsatile fashion by injections or continuously by pellets. The mode affected the response of tyrosine hydroxylase (TH) and GTP cyclohydrolase I (GTPCH) mRNAs differentially in the nucleus of solitary tract (NTS) and the locus coeruleus (LC). In rostral-medial NTS, TH mRNA levels were increased with injections, but declined in rats administered estradiol by pellets. In LC, a significant change was only observed in GTPCH with injections. These differences may reflect activation of different estrogen receptors (ER). The response to estradiol in the presence of ERα and ER β was examined in PC12 cell culture. Estradiol directly regulated promoter activity of TH, GTPCH and dopamine β-hydroxylase (DBH) genes. With ERα, 17 β-estradiol elevated TH promoter activity, while there was a decline with ERβ. In contrast, both DBH and GTPCH promoters were enhanced by 17 β-estradiol over a wide range of concentrations with either ER subtype. Thus, mode of administration, location examined and ER subtype expressed are important considerations in the overall response of catecholamine related enzymes to estradiol.  相似文献   

7.
Although most agree that 17β-estradiol is neuroprotective via a variety of mechanisms, less is known about the role that biological sex plays in receptor-mediated estradiol neuroprotection. To address this issue we isolated primary cortical neurons from rat pups sorted by sex and assessed the ability of estradiol to protect the neurons from death induced by glutamate. Five-minute pretreatment with 10–50 nM 17β-estradiol protected female but not male neurons from glutamate toxicity 24 h later. Both estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) are expressed in these cultures. Experiments using an ERα selective agonist or antagonist indicate that this receptor is important for neuroprotection in female cortical neurons. The ERβ selective agonist conveys a small degree of neuroprotection to both male and female cortical neurons. Interestingly, we found that 17α estradiol and the novel membrane estrogen receptor (mER) agonist STX, but not bovine serum albumin conjugated estradiol or the GPR30 agonist G1 were neuroprotective in both male and female neurons. Taken together these data highlight a role for ERα in sexually dimorphic neuroprotection.  相似文献   

8.
目的探讨雌激素受体(ER)亚型α和β mRNA及蛋白的异常表达与子宫内膜癌的发生发展的关系。方法应用半定量逆转录聚合酶链反应(RT—PCR)和免疫组织化学链霉菌抗生物素蛋白-过氧化酶连接法(SP法),检测18例正常子宫内膜组织、29例异常增生组织和50例子宫内膜癌组织中ERα、ERβ mRNA及蛋白的表达。结果①ERα mRNA在内膜癌组织中的阳性表达率和阳性表达水平明显低于异常增生内膜组织及正常内膜组织,三者比较有显著性差异(P〈0.01),ERα蛋白在这三组间的表达率变化相同(P〈0.05)。②ERβ mRNA在内膜癌组织中的阳性表达率和阳性表达水平明显低于增生性内膜组织及正常内膜组织,三者比较有显著性差异(P〈0.01),ERβ蛋白在这三组间的表达率变化相同(P〈0.01)。③ERα和ERβ mRNA平均表达水平比值(ERα/ERβ)在内膜癌组低于异常增生子宫内膜组织和正常子宫内膜组(P〈0.05)。结论ERα和ERβ表达的下调可能与子宫内膜癌的发生有关,在这个过程中ERα的下调起的作用大于ERβ。  相似文献   

9.
Human umbilical vein endothelial cells (HUVEC) exposed to the female sex hormone estradiol show different kinds of effects including increased elasticity, activation of plasma membrane Na+/H+ exchange, prostacyclin production, prevention of apoptosis and many others. The aim of this study was the systematic analysis of the immunolabelling of estrogen receptors (ERs), ERα and ERβ, in HUVEC after stimulation with different commercially available ER modulators and ER agonists or antagonists. HUVEC response to these substances was shown to be regulated via ERβ. ERα immunolabelling or up-regulation was abrogated after application of estrogen derivatives, selective estrogen receptor modulators (SERM) and ER agonists or antagonists. Immunolabelling of ERβ was significantly increased by estradiol, estrone, ethinylestradiol and tumour necrosis factor alpha (TNFα). SERM, such as Tamoxifen, and pure antagonists, such as ICI 182.780, stimulated ERβ in HUVEC at low concentrations, whereas higher concentrations inhibited ERβ immunolabelling. The pure estrogen receptor agonist 2,3-bis (4-hydroxyphenyl) proprionitrile (DPN) exhibited its activating potential at low concentrations. In contrast, higher concentrations resulted in a down-regulation of ERβ. Estrogenic effects in HUVEC, independent of stimulation or inhibition, are mediated via the ERβ. SERM such as Tamoxifen and ER antagonists such as ICI 182.780 act as ER activators in low concentrations, whereas higher concentrations lead to inhibitory effects.  相似文献   

10.
ObjectiveTo investigate the aberrant DNA methylation in promoter region of estrogen receptor α (ERα) in atherosclerosis (As) and the possible involvement of homocysteine (Hcy) in its pathogenesis.MethodsThe blood samples were collected from 54 patients with As approved by carotid colorized ultrasound examination and 28 healthy control subjects. The methylation status of CpG islands in ER-α gene promoter region of genome DNA was analyzed by nested-methylation-specific PCR (nMSP). tHcy was examined by fluorescent-biochemical method. Spearman rank correlation was used to analyse the relationship between the degree of methylation in ER-α gene and the level of tHcy. Cultured smooth muscle cells of Homo sapiens were treated by Hcy with different concentrations and different treating time, again the DNA methylation status was assayed by nMSP, and the proliferation of SMC was assayed by MTT.ResultsHypermethylation of ER-α gene promoter region was found in 38 cases of atherosclerosis patients, and the methylation frequency was 70.4%. While in healthy controls, just 8 of 28 samples hypermethylation was found, only 28.6% methylation frequency was detected, much lower than the one in atherosclerosis group (p < 0.05). Meanwhile, the level of tHcy in atherosclerosis group was significantly higher than that in control group (p < 0.05). The spearman rank correlation analysis explored an obvious correlation between the degree of methylation in ER-α gene and the level of tHcy (r = 0.809, p < 0.05), and the severity of atherosclerotic lesion was also heightened along with the increment of plasma level of tHcy. The cultured SMCs treated by Hcy resulted in de novo methylation in promoter region of ERα gene with a concentration and treating time-dependent manner, and a dose-dependent promoting effect on SMC proliferation. The in vivo and in vitro data coincidently showed that the Hcy could promote the hypermethylation of ERα gene, which may be an important mechanism for the pathogenesis of As.ConclusionHypermethylation of CpG islands in ER-α gene promoter region was found in much higher frequency in atherosclerosis patients, which is positively correlated with the increased level of plasma tHcy and the severity of atherosclerotic lesion, and the in vitro experimental results further extended above clinical data that HHcy can lead to the hypermethylation of ER-α gene, and hence to promote the occurrence and development of As.  相似文献   

11.
《Autoimmunity》2013,46(6):520-530
Estrogens and estrogen receptors (ERs) are potent regulators of the immune response. Disruption of ERα or modulation of its function by selective ligands during experimental autoimmune conditions changes the course of disease by influencing specific humoral and cellular responses. However, it is not known whether fluctuation in the ERα level and the variable accessibility to its ligands in immune cells influence the development of specific immune responses against auto-antigens. This study was designed to evaluate the expression level of ERα in splenic immune cells and the specific humoral immune response in male C3H/He/W mice immunized with syngeneic testicular germ cells (TGC) in the presence of tamoxifen. Levels of ERα protein in immune cell subpopulations of immunized mice (assessed by flow cytometry) increased in MHCII+CD86+, MHCII+CD86? , F4/80+MHCII+, immature macrophages (F4/80+/MHCII? ), and CD3+CD4+ T cells. Addition of tamoxifen decreased the level of ERα in MHCII+CD86+, MHCII+CD86? , F4/80+MHCII+, immature macrophages (F4/80+/MHCII? ), and the CD19+CD3? cell subpopulation of immunized mice. Therefore, immunization with syngeneic antigen and tamoxifen treatment evoked cell-type specific changes in the level of ERα. Irrespective of tamoxifen treatment the humoral response in immunized animals toward TGCs was similar, suggesting that modulation of the level of ERα in immune cells is not directly related to specific auto-antibody production.  相似文献   

12.

Background

Estrogen is the leading etiologic factor for endometrial cancer. Estrogen-induced proliferation of endometrial epithelial cells normally requires paracrine growth factors produced by stromal cells. Epidemiologic evidence indicates that dietary soy prevents endometrial cancer, and implicates the phytoestrogen genistein in this effect. However, results from previous studies are conflicting regarding the effects of genistein on hormone responsive cancers.

Methods

The effects of estrogen and genistein on proliferation of Ishikawa (IK) endometrial adenocarcinoma cells were examined in co-cultures of IK cells with endometrial stromal cells, recapitulating the heterotypic cell-to-cell interactions observed in vivo. The roles of estrogen receptor (ER)α and ERβ were evaluated using ERα and ERβ specific agonists. ER activation and cell proliferation in the IK epithelial cells were determined by alkaline phosphatase assay and Coulter counter enumeration, respectively.

Results

Both estrogen and genistein increased estrogen receptor-induced gene activity in IK cells over a range of concentrations. Estrogen alone but not genistein increased IK proliferation in co-cultures. When primed by estrogen treatment, increasing concentrations of genistein produced a biphasic effect on IK proliferation: nM concentrations inhibited estrogen-induced proliferation while μM concentrations increased proliferation. Studies with an ERβ-specific agonist produced similar results. Genistein did not influence the effects of estrogen on IK proliferation in monoculture.

Conclusions

Our study indicates that nutritionally relevant concentrations (nM) of genistein inhibit the proliferative effects of estrogen on endometrial adenocarcinoma cells presumably through activation of stromal cell ERβ. We believe that sub-micromolar concentrations of genistein may represent a novel adjuvant for endometrial cancer treatment and prevention.  相似文献   

13.
The bladder epithelial cells elicit robust innate immune responses against urinary tract infections (UTIs) for preventing the bacterial colonization. Physiological fluctuations in circulating estrogen levels in women increase the susceptibility to UTI pathogenesis, often resulting in adverse health outcomes. Dr adhesin bearing Escherichia coli (Dr E. coli) cause recurrent UTIs in menopausal women and acute pyelonephritis in pregnant women. Dr E. coli bind to epithelial cells via host innate immune receptor CD55, under hormonal influence. The role of estrogens or estrogen receptors (ERs) in regulating the innate immune responses in the bladder are poorly understood. In the current study, we investigated the role of ERα, ERβ and GPR30 in modulating the innate immune responses against Dr E. coli induced UTI using human bladder epithelial carcinoma 5637 cells (HBEC). Both ERα and ERβ agonist treatment in bladder cells induced a protection against Dr E. coli invasion via upregulation of TNFα and downregulation of CD55 and IL10, and these effects were reversed by action of ERα and ERβ antagoinsts. In contrast, the agonist-mediated activation of GPR30 led to an increased bacterial colonization due to suppression of innate immune factors in the bladder cells, and these effects were reversed by the antagonist-mediated suppression of GPR30. Further, siRNA-mediated ERα knockdown in the bladder cells reversed the protection against bacterial invasion observed in the ERα positive bladder cells, by modulating the gene expression of TNFα, CD55 and IL10, thus confirming the protective role of ERα. We demonstrate for the first time a protective role of nuclear ERs, ERα and ERβ but not of membrane ER, GPR30 against Dr E. coli invasion in HBEC 5637 cells. These findings have many clinical implications and suggest that ERs may serve as potential drug targets towards developing novel therapeutics for regulating local innate immunity and treating UTIs.  相似文献   

14.
15.
Estradiol and other steroid hormones modulate the nervous system and behavior on both acute and long-term time scales. Though estradiol was originally characterized as a regulator of gene expression through the action of nuclear estrogen receptors (ERs) that directly bind DNA, research over the past thirty years has firmly established that estradiol can bind to extra-nuclear ERs associated with the cellular membrane, producing changes in neurons through stimulation of various intracellular signaling pathways. Several studies have determined that the classical ERs, ERα and ERβ, mediate some of these fast-acting signaling pathways through activation of G proteins. Since ERα and ERβ are not G protein-coupled receptors, the mechanisms by which ERs can stimulate signal transduction pathways are a focus of recent research. Here we discuss recent studies illustrating one mechanism by which ERα and ERβ initiate these pathways: through direct association with metabotropic glutamate receptors (mGluRs). Estradiol binding to these membrane-localized estrogen receptors results in mGluR signaling independent of glutamate. ERs are organized with mGluRs into functional signaling microdomains via caveolin proteins. The pairing of ERs to specific mGluRs via caveolins is region specific, with ERs being linked to different mGluRs in hippocampal, striatal, and other neurons. It is becoming clear that ER signaling through mGluRs is one important mechanism by which estrogens can modulate neuron and glial physiology, ultimately impacting various aspects of nervous system function.  相似文献   

16.
PurposeWe aimed to evaluate the ERβ expression in the epithelium of the oral mucosa in menopausal women treated with oral, transdermal or local (vaginal) menopausal hormone therapy.Material/methodsIn this study, we included 60 women treated with oral, transdermal or vaginal menopausal hormone therapy. The study material was obtained from swabs taken from the buccal mucosa before administering HRT, and after 6 weeks, 3 months, 6 months and 12 months of therapy. We assessed estrogen receptor-β (ERβ) expression levels in subsequent swabs by immunohistochemical analysis.ResultsThe highest increase in the ERβ expression was observed after 3 months of oral and transdermal hormone therapy.ConclusionsOral and transdermal HRT may be an effective method of treatment of oral discomfort in menopausal women.  相似文献   

17.
卵巢切除对大鼠肾上腺雌激素受体亚型表达的影响   总被引:2,自引:0,他引:2  
目的通过对去卵巢大鼠雌激素受体(ER)亚型在肾上腺表达的观察,研究去卵巢对大鼠肾上腺功能影响的机制。方法选择成年Wistar大鼠20只,10只为假手术组,10只为模型组(去卵巢组),6周后处死大鼠,分离摘取肾上腺,称重后常规石蜡包埋切片,分别进行ERα、ERβ抗体的免疫组织化学染色,并取动物血清测量雌二醇(E2)和促卵泡生成素(FSH)的含量。结果1.ERα与ERβ在大鼠肾上腺均有表达,主要分布在肾上腺皮质部,以球状带和束状带为主,网状带有少量分布,ERβ的表达强于ERα。2.ERβ在大鼠模型组的表达强于假手术组,有统计学意义,ERα在模型组的表达略强于假手术组,但无统计学意义。3.卵巢切除后,大鼠血清FSH升高,E2下降,与假手术组相比,有显著差异。结论卵巢切除可影响雌激素受体在大鼠肾上腺的表达,尤其是对ERβ表达的影响较为显著。卵巢切除能够减少大鼠血清雌激素的分泌,使垂体反馈性的增加FSH的分泌。  相似文献   

18.
Changes in the expression of estrogen-related substances in monkeys’ brains at the menopausal transition, when estrogen deficit starts to occur, have not yet been examined thoroughly. In the present study, we immunohistochemically investigated the expression levels of estrogen receptor beta (ERβ) and aromatase (local estrogen synthesizing enzyme) in the hippocampal formation of premenopausal, menopausal, and ovariectomized premenopausal monkeys. In all monkeys tested, ERβ immunoreactivity was observed in interneurons located in the subiculum and the Ammon's horn, and most of these ERβ-immunoreactive neurons coexpressed a GABAergic neuron marker, parvalbumin. In the menopausal monkeys who exhibited a decline in estrogen concentration, hippocampal ERβ was highly upregulated, while aromatase expression was not markedly changed. By contrast, aromatase in the ovariectomized monkeys was significantly upregulated, while ERβ expression was not changed. In the brains of ovariectomized and menopausal monkeys, depletion of ovary-derived estrogen brought about different reactions which may be attributed to the senescence of brain aging.  相似文献   

19.
20.
Anastrozole and RU486 are shown to reduce hormone-responsive breast cancer progression when used as adjuvant treatments to surgical intervention, however, a high incidence of cancer recurrence remains. Estrogen receptor alpha (ERα) and Mucin 1 (MUC1), a glycoprotein, are both implicated in breast cancer progression. We assessed whether Anastrozole and RU486 treatment affects the expression of, and relationship between, ERα and MUC1 in the ERα+ MUC1+ MCF-7 breast cancer cell line. MCF-7 cells, treated with physiological concentrations of either Anastrozole or RU486 for 18 h or 72 h, were subjected to immunolocalization of both markers. CellProfiler software was used to quantify intensity for statistical analyses. ERα expression increased at both time periods following treatment. MUC1 expression increased with RU486-treatment at both times, whereas Anastrozole induced increased MUC1 expression at 72 h only. The biomarkers demonstrated increased point association at 72 h within treatment groups despite MUC1 diverging from correlation with ERα. We propose that tumor progression is independent of MUC1 and ERα correlation. These preliminary results indicate that withdrawal of adjuvant treatment may result in residual cell populations expressing increased ERα and MUC1. This phenotype may allow enhanced estrogenic and metastatic capacity influencing cancer recurrence, a hypothesis we are investigating further.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号