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Several reports deal with possible effects of female sex hormones on human umbilical vein endothelial cells (HUVEC) including elasticity, activation of plasma membrane Na(+)/H(+) exchange, VEGF receptor Flk-1/KDR and many others. In contrast to those findings, some publications pointed out that HUVEC lack expression of both the estrogen receptor (ER) and/or the progesterone receptor (PR). Because the majority of these investigations were carried out at a time period, when only one ER and one PR was known, the aim of this study was the systematic analysis of ERalpha and ERbeta as well as PR-A and PR-B expression in HUVEC with specific monoclonal antibodies by immunocytochemistry and quantitative RT-PCR (TaqMan). As a result, we could show that HUVEC lack ERalpha but express ERbeta. The expression of ERbeta could be significantly upregulated with 17beta-estradiol on mRNA and protein level. In addition, HUVEC express PR-A but not PR-B. PR-A expression could be significantly upregulated with progesterone, again on mRNA and protein level. We conclude that estrogenic effects on HUVEC are mediated via the ERbeta and gestagens act via the PR-A pathway.  相似文献   

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《Neuron》2020,105(5):761-763
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The endoplasmic reticulum (ER) network is extremely dynamic in animal cells, yet little is known about the mechanism and function of its movements. The most common ER dynamic, termed ER sliding, involves ER tubule extension along stable microtubules (MTs). In this study, we show that ER sliding occurs on nocodazole-resistant MTs that are posttranslationally modified by acetylation. We demonstrate that high MT curvature is a good indicator of MT acetylation and show in live cells that ER sliding occurs predominantly on these curved, acetylated MTs. Furthermore, increasing MT acetylation by drug treatment increases the frequency of ER sliding. One purpose of the ER sliding on modified MT tracts could be to regulate its interorganelle contacts. We find that all mitochondria and many endosomes maintain contact with the ER despite the movements of each. However, mitochondria, but not endosomes, preferentially localize to acetylated MTs. Thus, different ER dynamics may occur on distinct MT populations to establish or maintain contacts with different organelles.  相似文献   

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Estrogens act through binding to estrogen receptor α (ERα) and β (ERβ). Studies in knockout mice have shown that the absence of ERα leads to the polycystic ovary syndrome (PCOS) phenotype. Furthermore, the expression of ERβ gene is lower in follicles derived from women with PCOS compared with healthy women. The aim of this study was to investigate the importance of ERα and ERβ gene polymorphisms in PCOS. A cohort of 180 women with PCOS and 140 healthy controls were recruited, and the PvuII and XbaI polymorphisms of ERα, as well as, the AluI and RsaI polymorphisms of ERβ were genotyped. No difference was found in the distribution of these polymorphisms between patients and healthy controls. However, in PCOS women, carriers of TC and TT genotypes of PvuII polymorphism had lower fasting glucose to insulin ratio compared with carriers of CC genotype (p = 0.029). In addition, the presence of AA genotype of XbaI polymorphism was associated with lower levels of follicle-stimulating hormone (FSH) compared with the presence of AG and GG genotypes (p = 0.03). The association of ERα polymorphisms with insulin resistance indices and FSH levels emphasizes the importance of ERα as a genetic modifier of the PCOS phenotype.  相似文献   

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The mechanisms by which varicocele affects fertility remain undetermined. Estrogens play a key role in the human male reproduction and human sperm expresses the estrogen receptors (ERs) and aromatase. In this study, by Western blotting we evidenced the ERs content concomitantly in healthy sperm and in oligoastenoteratozoospermic (OAT) samples without and with varicocele. In varicocele a strong reduction of the ERβ was observed, while the ERα was almost absent. Besides, transmission electron microscopy (TEM) confirmed the reduction of ERs expression in "varicocele" sperm, indicating that varicocele has a detrimental effect on sperm structure at molecular level. To further define the estrogen significance in male gamete and the pathophysiology of varicocele we investigated both the expression of ERα and ERβ in normal and pathologic sperm samples as well as we evaluated estradiol (E2) action on lipid and glucose sperm metabolism. Responses to E2 treatments on cholesterol efflux, protein tyrosine phosphorylations, motility, and acrosin activity in varicocele sperm were reduced or absent. The evaluation of the triglycerides content, lipase and acyl-CoA dehydrogenase activities, suggest that E2 exerts a lipolytic effect on human sperm metabolism. Concerning glucose metabolism, it appears that E2 induces G6PDH activity concomitantly to the insulin secretion. In "varicocele" sperm, the E2 did not induce energy expenditure. OAT sperm had E2-responsiveness but in a lesser extent with respect healthy sperm. This study discovered a novel role for E2/ERs in human sperm physiology, since they modulate sperm metabolism and new detrimental effects related to the pathophysiology of the varicocele condition.  相似文献   

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Summary Human 2macroglobulin combines two unique features: the non-active site directed inhibition of virtually all endoproteases and the selective clearance of 2M-endoprotease complexes by receptor-mediated endocytosis. To study the molecular details of the mechanisms involved, primary amines were found to be worthwhile probes at three specific levels: the inactivation of native 2M, the derivatization by factor XIII and the cellular process of receptor-recycling. In this paper published data are supplemented with recently obtained evidence to discuss and speculate on the possible action or involvement of transglutaminase activities, indicated by the effects of the primary amines.  相似文献   

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The effects of modification of the arginine/lysine ratio of dietary protein on the cholesterol kinetics were studied in male rats. Single amino acids (lysine to soybean protein and arginine to casein) were added to approximate the arginine/lysine ratio in different proteins. After acclimation to these diets for 30 days, rats were administered intravenous [14C]cholesterol and oral [3H]cholesterol. Analysis of the die-away curve of [14C]cholesterol showed an apparent independence of cholesterol kinetics to the dietary manipulations, but there was a moderate reduction of the size of the slowly exchangeable pool and of the biliary concentration of cholesterol when lysine was added to soybean protein. Addition of amino acids neither influenced cholesterol absorption nor the fecal excretion of the radioactivities from labeled cholesterol. The results indicate that manipulating the arginine/lysine ratio of dietary protein by adding single amino acids is not necessarily effective in ameliorating cholesterol metabolism in rats, although the arginine addition caused a significant reduction of serum cholesterol and triglyceride.  相似文献   

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LRP16是一个雌激素(E2)通过受体α(ERα)诱导表达的靶基因,LRP16不仅促进人乳腺癌MCF-7细胞的增殖,而且促进细胞的侵袭生长,但对LRP16作用的分子机制尚不清楚.首先,检测到LRP16表达缺陷明显削弱了MCF-7细胞对E2的反应性增殖能力;采用Northern 印迹与Western印迹法,进一步检测到抑制LRP16表达,明显损害了ERα靶基因对E2诱导上调的反应性,这些基因包括了cyclin D1, c-myc, c-fos,MTA3, pS2和维甲酸受体α基因(RARα)等;以上结果提示,LRP16参与了ERα介导的信号途径.将ERα模式启动子报告基因3×ERE-TATA-luc,ERα以及LRP16表达载体共转染MCF-7与HeLa细胞.结果发现,LRP16增强了ERα对报告基因的转录激活,并呈现对LRP16的剂量依赖性;进而采用GST-pull down以及免疫共沉淀方法证实了LRP16与ERα之间的直接相互作用,该作用不依赖于E2的存在,但可被E2增强;采用哺乳动物双杂交方法进一步证实了ERα与LRP16相互作用位点存在于A/B区的激活功能域-1(AF1).以上结果表明,LRP16是ERα的一个共激活因子,通过相互作用,LRP16增强了ERα介导转录活性.该研究为LRP16促进ERα阳性乳腺癌细胞增殖与侵袭生长提供了合理的分子解释.  相似文献   

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We previously showed that fluorination of the carborane-containing selective estrogen receptor modulator (SERM) BE360 altered the agonist/antagonist activity balance and the estrogen receptor (ER) α/β subtype selectivity. Here, we designed and synthesized a series of fluorinated carboranyl phenols as candidate ERβ-selective ligands. Introduction of a fluorine atom onto the carborane cage commonly reduced the binding affinity for ERα, to an extent that depended on the other substituents present. The B-fluorinated m-carboranyl phenol 4a showed fourfold more potent ERβ-binding affinity than the parent non-fluorinated compound 7. 1-Iodo-9-fluoro-m-carboranyl phenol 4f showed high ERβ-binding affinity with an ERβ/ERα selectivity ratio of 8.2. Among the compounds tested, 6 showed the highest ERβ selectivity (10.1-fold) and the highest ER-agonistic activity (EC50: 5.1 × 10?10 M) in MCF-7 cell proliferation assay.  相似文献   

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It was a common belief in the first half of this century that human schistosomiasis would not become established in India, despite the regular introduction of the disease by soldiers returning from active campaigns. This was based on the absence of known intermediate hosts for Schistosoma spp, yet in 1952 a focus of human schistosomiasis was discovered in Gimvi village, Ratnagiri District, Maharashtra State. The focus seems to be in recession, but the proposed large irrigation schemes centering upon the Narmada River may exacerbate schistosomiasis in domestic stock, and possibly in humans. Here, Vaughan Southgate and Matesh Agrawal discuss the findings in Gimvi, and the possibilities of human schistosomiasis in India in the future.  相似文献   

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X-Linkage of Human α-Galactosidase   总被引:5,自引:0,他引:5  
A deficiency in α-galactosidase (α-Gal) activity–as measured aspecifically with the use of artificial substrates–is a regular feature in leucocytes and fibroblasts of patients affected by angiokeratoma corporis diffusum or Fabry's disease, a well-known X-linked trait in man1–4. Fibroblast clones derived from mothers of affected males exhibit either normal or deficient activity of α-galactosidase. This demonstrates that the deficiency of α-galactosidase is caused by an X-linked mutation, but does not necessarily prove that the structural locus for this enzyme is itself located on the X-chromosome.  相似文献   

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ABSTRACT

Since the late 1970s, scientific evidence has accumulated showing that pet ownership can have positive effects on people’s physical and mental wellbeing. This paper reviews the current state of affairs regarding the relationship between companion animals and human health, focusing on both the physical and psychological health outcomes related to human–animal interactions. Although designed to set the general scene on the link between animals and human wellbeing, research specific to older adults is highlighted where relevant. A particular emphasis is placed on disorders prevalent in modern-day society, notably cardiovascular disease and depression. The possible mechanisms by which companion animals might be able to enhance human wellbeing and quality of life are discussed, focusing on routes including, amongst others, the provision of companionship, social lubrication, and improvements to physical fitness. The role of the social bonding hormone, oxytocin, in facilitating attachment to our pets and the implications for human health is also discussed. Inconsistencies in the literature and methodological limitations are highlighted throughout. It is concluded that future human–animal interaction experiments should aim to account for the confounding variables that are inherent in studies of this nature.  相似文献   

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雌激素受体β(ERβ)在乳腺癌发生发展中起着重要的作用,寻找与ERβ相互作用的共调节因子对阐明ER信号通路具有重要价值.应用酵母双杂交技术,以ERβ的AF2结构域为诱饵蛋白从人乳腺文库中筛选出了与之相互作用的蛋白26S蛋白酶的亚单位ATPase 5(PSMC5).GST沉淀实验表明,PSMC5在体外特异地与ERβ相结合.转录活性实验表明,PSMC5以激素依赖的方式降低ERβ转录活性.上述结果提示,PSMC5可能通过影响ERβ信号途径在乳腺癌发生发展中起着重要的作用.  相似文献   

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ABSTRACT

In 2016, the Gerontological Society of America (GSA) developed a research focus on the benefits and potential risks associated with pets among older adults. With the goal of developing a roadmap for human–animal interaction (HAI) research in older people residing in both the community and institutions, GSA convened a workshop of international experts and policy-makers in the fields of aging and HAI. The status of current knowledge was shared on the success factors for healthy aging and the potential challenges (GSA, 2016). Participants considered what roles pets might play in the lives of older adults and their potential to mitigate loneliness, social isolation, and depression, and to enhance mobility and cognitive function. Existing research was shared to provide insights into the ways in which pets can impact older adults and their caregivers and to identify where further research is needed. This paper introduces a series of papers from that meeting, with some additional papers from meeting attendees to expand on the topics covered and provide key perspectives and gaps in information needed, as a foundation for those considering research into this topic. Although HAI/Animal-Assistant Intervention (AAI) research is in its infancy, there is some evidence that pet ownership or animal interaction can have major benefits for many older adults. At the same time, there are some risks to both the pet and the older adult that need to be addressed. Innovative approaches to both AAIs and the ways to overcome challenges are presented in this themed issue of Anthrozoös. Our hope is that the findings from these reviews and reports will stimulate additional work in this area.  相似文献   

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目的研究雌激素受体α,β在比格犬卵巢及子宫内的定位。方法采用免疫组化SP法DAB显色结合BCIP/NBT及AEC显色检测ERα、ERβ在比格犬子宫及卵巢内的表达。结果比格犬ERα主要表达于卵泡颗粒细胞、卵巢间质腺腺上皮细胞及子宫内膜腺体腺上皮细胞胞核内,胞质内仅有少量表达,而在卵泡膜内膜的间质细胞,腺体周围的基质细胞及小动脉血管内皮细胞和平滑肌细胞、小静脉内皮细胞的胞核内有少量表达。而ERβ则以相同的组织特异性主要表达于上述组织细胞的胞质内,在胞核内有微弱表达。ERα表达于膜黄体细胞的胞核内,而在黄体颗粒细胞胞核与胞质内均有表达。而ERβ则仍特异表达于不同生理阶段黄体细胞的胞质内。BCIP/NBT与AEC双染未见ERα、ERβ在子宫内有明显的共表达现象。结论比格犬ERα、ERβ在子宫与卵巢组织内定位不同,ERα主要定位于胞核,在胞质内有微弱表达,而ERβ主要定位于胞质,在胞核内有零星表达。  相似文献   

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雌激素受体(ER)/雌二醇(E2)调控其下游靶基因的转录及蛋白表达,在乳腺癌的发生发展过程中发挥至关重要的作用,寻找新的ER下游靶基因可以为乳腺癌的临床治疗提供新的治疗靶点。该研究通过Western blot和qPCR方法确定了一个新的ER下游靶基因BAP18,其表达量可以被E2和ER上调,同时使用拮抗E2和ER的药物如他莫昔芬或氟维斯群可以使BAP18表达量下降。通过生物信息学分析确定了BAP18转录起始位点前潜在的ER结合位点,构建了检测BAP18转录活性的质粒后,用荧光素酶双报告基因实验和染色质免疫共沉淀实验确定了BAP18启动子上ER的结合位点和上调转录的区域。凝胶迁移实验确定ER可以直接结合BAP18的启动子DNA。最后利用CRISPR-Cas9定向敲除BAP18,发现BAP18的敲除可以导致ER阳性乳腺癌细胞的生长和增殖减慢且凋亡增加。该研究鉴定了BAP18是ER下游靶基因,其在乳腺癌中有促癌作用。BAP18的发现有望为ER阳性乳腺癌的临床治疗提供理论基础和新的治疗靶点。  相似文献   

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