ERα Levels Research Articles

Mechanism of traditional Chinese medicine balancing Yin-Yang by targeting ERα/ERβ and its application in treatment of menopausal syndrome

The coordination and unification of Yin and Yang are the basis of normal human life activities. Along with the age growth and aging of the body, women will suffer from menopausal syndrome during menopause. In addition to the significant changes in the genital system, there are also pathological manifestations in estrogen target points including bone, nerve and cardiovascular systems, due to the imbalance of Yin and Yang. Besides the insufficiency of estrogen, the main cause of menopausal syndrome is the changes in the response of target organs to estrogen. In other words, the biological effects mediated by estrogen receptor(ER) alpha and beta subtypes in target cells are often different or even opposite; the changes of expression level and ratio of ERα and ERβ are also important causes for the abnormal estrogenic effects in target organs and the imbalance of Yin and Yang of the body. Therefore, on one hand, the therapeutic mechanism of drugs is ER-mediated estrogenic effect. On the other hand, the drugs have a regulatory effect on ER subtype expression in target cells and Yin-Yang state in target organs and even organisms, so as to cause further changes in the response of target cells to estrogen or estrogenic components, and exert its therapeutic effects. This paper reviews the pharmacological mechanism of gynecological traditional Chinese medicine in harmonizing Yin and Yang in estrogen-positive target cells and the clinical efficacy in the following aspects, including estrogen and its mechanism, the estrogenic effect of ER in traditional Chinese medicine and the mechanism of ER subtype in balancing Yin and Yang and mediating and regulating the main target tissues in menopausal syndrome treatment.

The content of gonadotropin-releasing hormone (GnRH), kisspeptin, and estrogen receptors (ERα/ERβ) in the anteromedial hypothalamus displays daily variations throughout the rat estrous cycle.

The content of gonadotropin-releasing hormone (GnRH), its mRNA, and estrogen receptor alpha (ERα) and beta (ERβ) in the hypothalamus varies throughout the estrous cycle. Furthermore, the abundance of these molecules displays asymmetry between the right and left side. In the present study, we investigated the changes in the content of ERα, ERβ, kisspeptin, and GnRH by western blot in the left and right anteromedial hypothalamus, at four different times during each stage of the rat estrous cycle. The serum levels of the follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were also measured. ERα and ERβ levels changed depending on the stage of the estrous cycle, meanwhile that of kisspeptin was modified according to both the hour of the day and the stage of the cycle. Except in estrus day, ERβ was higher in the right hypothalamus, while ERα was similar in both sides. During both proestrus and estrus, the content of kisspeptin and GnRH was higher in the right hypothalamus. The highest levels of FSH and LH occurred at 17:00h of proestrus. But at estrus, the highest FSH levels were observed at 08:00h and the lowest at 17:00h. Thus, the current results show that the content of ERα, ERβ, kisspeptin, and GnRH in the anteromedial hypothalamus are regulated as a function of the stage of the estrous cycle and the hour of the day. Furthermore, the content of these proteins is regularly higher in the right anteromedial hypothalamus, regardless of the stage of the cycle or time of the day.

The Cannabinoid Delta-9-tetrahydrocannabinol Disrupts Estrogen Signaling in Human Placenta.

Cannabis consumption is increasing worldwide either for recreational or medical purposes. Its use during gestation is associated with negative pregnancy outcomes such as, intrauterine growth restriction, preterm birth, low birth weight, and increased risk of miscarriage, though the underlying molecular mechanisms are unknown. Cannabis sativa main psychoactive compound, Δ9-tetrahydrocannabinol (THC) is highly lipophilic, and as such, readily crosses the placenta. Consequently, THC may alter normal placental development and function. Here, we hypothesize alterations of placental steroidogenesis caused by THC exposure. The impact on placental estrogenic signaling was examined by studying THC effects upon the enzyme involved in estrogens production, aromatase and on estrogen receptor α (ERα), using placental explants, and the cytotrophoblast cell model BeWo. Aromatase expression was upregulated by THC, being this effect potentiated by estradiol. THC also increased ERα expression. Actions on aromatase were ERα-mediated, as were abolished by the selective ER downregulator ICI-182780 and dependent on the cannabinoid receptor CB1 activation. Furthermore, the presence of the aromatase inhibitor Exemestane did not affect THC-induced increase in ERα expression. However, THC effects on ERα levels were reversed by the antagonists of CB1 and CB2 receptors AM281 and AM630, respectively. Thus, we demonstrate major alterations in estrogen signaling caused by THC, providing new insight on how cannabis consumption leads to negative pregnancy outcomes, likely through placental endocrine alterations. Data presented in this study, together with our recently reported evidence on THC disruption of placental endocannabinoid homeostasis, represent a step forward into a deeper comprehension of the puzzling actions of THC.

Immunohistochemical expression of estrogen receptor α, Bcl-2 and NF-κB P65 in the polyps of patients with and without endometriosis.

To compare the expression of estrogen receptor α (ERα), Bcl-2 and NF-κB P65 in endometrial polyps from patients with and without endometriosis. Immunohistochemistry was used to characterize the expression of ERα, Bcl-2 and NF-κB P65 in proliferative phase endometrial polyps from patients with and without endometriosis. H-Scores indicating the staining intensity for ERα, Bcl-2 and NF-κB P65 in the glandular epithelium and stroma were measured separately. Apoptotic cells were detected with the use of the dUTP nick-end labeling (TUNEL) assay. Bcl-2 was expressed in the cytoplasm of glandular epithelial cells, whereas ERα was expressed in the nuclei of both glandular epithelial and stromal cells. NF-κB P65 was observed in the cytoplasm of both glandular epithelial and stromal cells. The H-scores for Bcl-2 in the endometrial glands significantly higher in the endometriosis polyp group than in the non-endometriosis polyp group. The H-scores for ERα in both stromal and glandular epithelial cells were significantly higher in the endometriosis polyp group than in the non-endometriosis polyp group. The H-scores for Bcl-2 and ERα were positively correlated in all of the women examined. Apoptotic cells in the endometriosis polyp group were significantly less than that of the non-endometriosis polyp group. There expression levels of Bcl-2 and ERα, both of which were significantly increased in the polyps of endometriosis patients compared to those of patients without endometriosis, were positively correlated. These results suggested that imbalanced apoptosis secondary to abnormally high ERα expression was responsible for the high prevalence of polyps in endometriosis patients.

Altered aryl-hydrocarbon-receptor signalling affects regulatory and effector cell immunity in autoimmune hepatitis

In autoimmune hepatitis (AIH), the imbalance between regulatory T cells (Tregs) and T-helper type 17 (Th17) cells has been linked to low levels of CD39, an ectoenzyme that hydrolyses ATP, ultimately generating immunosuppressive adenosine. Upregulation of CD39 results from activation of aryl hydrocarbon receptor (AHR), which mediates toxin responses to modulate T-cell immunity. In this study, we investigated whether altered AHR signalling underlies defective CD39 expression and function in AIH Tregs and Th17 cells, therefore contributing to regulatory/effector cell imbalance. Tregs and Th17 cells, obtained from the peripheral blood of 49 patients with AIH and 21 healthy individuals (HI), were tested for response to endogenous and exogenous AHR ligands. When compared to those of HI, AIH-derived Tregs and Th17 cells displayed impaired responses to AHR activation, reflected by impaired upregulation of CD39, delayed increase in ectoenzymatic activity, and defective Treg suppressive function. These impairments resulted, at least in part, from heightened levels of AHRR and Erα in Tregs and high HIF-1α in Th17 cells, and were reverted upon molecular blockade. Importantly, in AIH-derived Tregs, the binding affinity of AHR was higher for Erα than ARNT. In AIH, high levels of AHRR and HIF-1α inhibit AHR signalling in Tregs and Th17 cells. AHR non-canonical binding to Erα further amplifies the lack of effective CD39 upregulation. Blockade of these inhibitory and/or non-canonical activation pathways represents a potential therapeutic approach to restore CD39 and immunohomeostasis in AIH. In patients with autoimmune hepatitis, the imbalance between regulatory T cells and T helper type-17 cells is linked to dysfunction of the aryl hydrocarbon receptor pathway, resulting from aberrant inhibition or non-canonical activation. These alterations impair Treg- and Th17 cell-induced upregulation of CD39, an ectoenzyme key to immunoregulation. Blockade of excessive inhibition or non-canonical activation of the aryl hydrocarbon receptor pathway might represent a novel therapeutic strategy to control inflammation while restoring immune balance in autoimmune hepatitis.

An HMGA2-p62-ERα axis regulates uterine leiomyomas proliferation.

Uterine leiomyomas (ULM) are a major public health issue contributing to high morbidity and poor pregnancy outcomes. However, its molecular pathogenesis is poorly understood. HMGA2-ULM is the second major subtype of human ULM and associates with large sizes, fast-growth, and high percentages of estrogen receptor α (ERα). As altered ERα expression plays a distinct role in ULM growth, here, we investigate a regulatory mechanism driving ULM growth via HMGA2 and ERα. We reveal a positive correlation of HMGA2 with ERα protein and demonstrate that HMGA2 promotes ULM cells proliferation via ERα. In addition, autophagy pathway and p62/SQSTM1 (a selective autophagy receptor) are found to participate in the regulation of HMGA2 and ERα. Moreover, HMGA2 suppresses the transcription of p62 by binding to its promoter, meanwhile, p62 interacts with ERα, and inhibition of p62 increases ERα expression and enhances cell viability in ULM, suggesting a novel mechanism of the HMGA2-p62-ERα axis in ULM proliferation. Notably, rapamycin, a familiar autophagy agonist, reduces ERα levels and the proliferation ability of ULM cells. This study demonstrates a causal role of the HMGA2-p62-ERα axis in preventing autophagy and increasing ERα expression in HMGA2-ULM. Therefore, blocking HMGA2-p62-ERα axis and targeting autophagy pathway establish a roadmap toward HMGA2-ULM medical treatment.

Sex-specific acclimation of A2 noradrenergic neuron dopamine-β-hydroxylase and estrogen receptor variant protein and 5’-AMP-Activated protein kinase reactivity to recurring hypoglycemia in rat

Hindbrain estrogen receptors (ER) impose sex-dimorphic control of counter-regulatory hormone and hypothalamic glucoregulatory transmitter and glycogen metabolic responses to hypoglycemia. A2 noradrenergic neurons are estradiol- and metabolic-sensitive. Estradiol controls dopamine-beta-hydroxylase (DBH) protein habituation to recurrent insulin-induced hypoglycemia (RIIH) in females. Current research investigated the premise that sex-dimorphic patterns of A2 ER variant acclimation to RIIH correlate with differential A2 DBH and 5’-AMP-activated protein kinase (AMPK) adaptation to RIIH. A2 neurons were laser-catapult-microdissected from male and female rats after one or four insulin injections for Western blot analysis. A2 pAMPK and DBH levels were increased in males, but suppressed in females after single insulin dosing. ER-alpha (ERα) and -beta (ERβ) protein profiles were unaffected or decreased by acute hypoglycemia in each sex, whereas G protein-linked ER-1 (GPER) reactivity varied by sex. Antecedent hypoglycemia diminished basal A2 ERα/GPER and elevated ERβ content in each sex, yet reduced pAMPK and DBH levels in female rats only. Reintroduced hypoglycemia suppressed A2 ERβ levels in each sex, but altered DBH (↓), ERα (↓), and GPER (↑) levels in males only. Data document sex differences in A2 DBH adaptation to RIIH, e.g. a shift from positive-to-negative response in males versus loss of negative reactivity in females, as well as attenuated AMPK activation in both sexes. Between hypoglycemic episodes, A2 neurons in each sex likely exhibit diminished sensitivity to ERα/GPER signaling, but heightened receptivity to ERβ input. RIIH-induced changes in ERα and GPER expression in male but not female may contribute to DBH suppression (males) versus no change (females) relative to adapted baseline expression.

Exosomes Mediated Transfer of Circ_UBE2D2 Enhances the Resistance of Breast Cancer to Tamoxifen by Binding to MiR-200a-3p.

BackgroundCircular RNA UBE2D2 (circ_UBE2D2) has been found to be involved in the progression of breast cancer. Exosomes are critical mediators of intercellular communication, however, the function of exosomal circ_UBE2D2 in breast cancer remains vague.Material/MethodsCell viability was measured by Cell Counting Kit-8 assay. Western blot was used to detect the levels of estrogen receptor alpha (ERα), E-cadherin, vimentin, CD9, and CD63. Migrated and invaded cells were examined using Transwell assay. Circ_UBE2D2 and microRNA (miR)-200a-3p levels were detected using quantitative real-time polymerase chain reaction. Exosomes were isolated by ultracentrifugation method. The interaction between circ_UBE2D2 and miR-200a-3p was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation assay. Murine xenograft model was established to conduct in vivo experiments.ResultsWe found that circ_UBE2D2 was upregulated in breast cancer tamoxifen-resistant tissues and cell lines, and circ_UBE2D2 deletion mitigated tamoxifen resistance in breast cancer cells. Circ_UBE2D2 was also significantly loaded in exosomes isolated from resistant cells and could be transferred to parental cells. MiR-200a-3p was a target of circ_UBE2D2, and we demonstrated that exosomes mediated transfer of circ_UBE2D2 interacted with miR-200a-3p to enhance tamoxifen resistance of breast cancer cells by regulating cell viability, metastasis, and the level of ERα in vivo and in vitro.ConclusionsExosomes mediated transfer of circ_UBE2D2 reinforced tamoxifen resistance in breast cancer by binding to miR-200a-3p, providing new insights into the boost of the effectiveness of tamoxifen on breast cancer patients.

Bisphenol A in utero exposure induces ovary dysfunction in mice offspring and the ameliorating effects of Cuscuta chinensis flavonoids.

To study the alleviating effects of flavonoids from Cuscuta chinensis (CCFs) on ovary injury in female offspring of pregnant mice exposed to BPA, five groups (n = 20) of pregnant mice were intragastrically administrated with BPA (5mg/kg/day) and CCFs (20mg/kg/day, 30mg/kg/day, 40mg/kg/day) at pregnancy days 1-18. The ovaries and serum of F1 female mice were collected at postnatal day (PND) 21 and PND 56 for the detection of related indicators. The ovarian and testicular histomorphologies were observed with hematoxylin-eosin staining (H&E). The levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) and the contents of estradiol (E2), progesterone (P4), and testosterone (T) in serum were detected by radioimmunoassay. The contents of ovarian and testicular estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ) were detected by enzyme-linked immunosorbent assay (ELISA). The expression of caspase-7, caspase-9, bcl-2, and bax in ovaries and testes of offspring mice were detected by Western blot, and apoptosis in ovaries and testes was detected by TUNEL. The mRNA relative transcription levels of ERα, progesterone receptor (PgR), DNA methyltransferase1 (Dnmt1), DNA methyltransferase3A (Dnmt3A), and DNA methyltransferase3B (Dnmt3B) were detected by real-time quantitative PCR (RT-qPCR). The ovary of female offspring with PND 56 was treated with bisulfite sequence PCR (BSP). Our results showed that, compared with the BPA group, 40mg/kg CCFs significantly reduced the ovarian index of F1 females and the ovarian cytoapoptosis (P< 0.01). CCFs also can alleviate the injure of the levels of serum hormone, hormone receptors, and DNMTs induced by BPA in F1 females at PND 21 and PND 56. Forty milligrams per kilogram of CCFs significantly inhibited the hypermethylation of the H19/Igf2 imprinted gene induced by BPA (P< 0.01). It indicated that CCFs adjusted H19/Igf2 methylation by increasing the expression of DNMTs, thereby increasing the levels of reproductive hormones and receptors along with reducing the cytoapoptosis.

Effect of Guanxin Danshen Formulation on diabetic kidney disease in db/db mice through regulation of Nrf2 pathway

Diabetic kidney disease(DKD) has become a primary cause of end-stage kidney disease, without any effective treatment available. In this study, we assessed the protective effect of Guanxin Danshen Formulation(GXDSF) on diabetic nephropathy in db/db mice. The db/m and db/db mice were randomly divided into 4 groups: control group, model group, metformin group, and GXDSF group. After 8 weeks' treatment with GXDSF, metformin or normal saline, the mice were sacrificed, and the blood and kidney tissues were collected for the further analysis. Compared with the model group, TG, TCH and LDL levels significantly decreased in the GXDSF group. The results from HE and PAS staining showed that db/db mice exhibited abnormal kidney tissues with increased glomerular volume, basement-membrane thickening and mesangial cell proliferation, which could be significantly alleviated by GXDSF treatment. GXDSF treatment also reduced serum creatinine and BUN. Meanwhile, GXDSF treatment markedly elevated GSH-PX levels, while reduced LDH and MDA levels in the kidney tissues. Western blot assay showed that GXDSF evidently up-regulated protein levels of ERα and p-Akt, and subsequently promoted HO-1 expression mediated by Nrf2. These data collectively indicated that GXDSF protects db/db mice against DN by regulating ERα and Nrf2-mediated HO-1 expression.

Differential ESR1 Promoter Methylation in the Peripheral Blood-Findings from the Women 40+ Healthy Aging Study.

Background Estrogen receptor α (ERα) contributes to maintaining biological processes preserving health during aging. DNA methylation changes of ERα gene (ESR1) were established as playing a direct role in the regulation of ERα levels. In this study, we hypothesized decreased DNA methylation of ESR1 associated with postmenopause, lower estradiol (E2) levels, and increased age among healthy middle-aged and older women. Methods We assessed DNA methylation of ESR1 promoter region from dried blood spots (DBSs) and E2 from saliva samples in 130 healthy women aged 40–73 years. Results We found that postmenopause and lower E2 levels were associated with lower DNA methylation of a distal regulatory region, but not with DNA methylation of proximal promoters. Conclusion Our results indicate that decreased methylation of ESR1 cytosine-phosphate-guanine island (CpGI) shore may be associated with conditions of lower E2 in older healthy women.

Estrogen receptor-α immunoreactivity predicts symptom severity and pain recurrence in deep endometriosis

To determine the relationship between steroid receptor expression and pain symptoms in endometriosis. Cross-sectional SETTING: University Hospital PATIENT(S): Women with endometriosis (N = 92). Tissue samples were obtained from patients with surgically diagnosed endometriosis. A tissue microarray (TMA) was generated from patients with endometriosis. Data were collected on the presence and severity of dysmenorrhea, deep dyspareunia, dyschezia, and nonmenstrual pain by use of a numerical rating scale (NRS) at the time of surgery and after 1 year. The intensity of receptor expression was evaluated through immunohistochemistry and measured according to an immunoreactive score (IRS). Clinical variables were correlated to IRS by multivariate logistic regression analysis. Estrogen receptor-α (ER-α), progesterone receptor (PR), androgen receptor (AR), and aromatase expression differed among study participants. ER-α expression was reduced by progestin therapy, whereas of expressions of PR, AR, and aromatase were unchanged. Higher ER-α expression increased the likelihood of moderate to severe dysmenorrhea and deep dyspareunia in women not receiving hormonal treatment. In women receiving progestin therapy, persistently higher ER-α expression was correlated with greater likelihood of deep dyspareunia, severe dyschezia, and endometriosis-associated pain persistence at 1 year. ER-α, PR, AR, and aromatase were all expressed in deep endometriosis. ER-α levels best correlated with severity of symptoms, which suggests that ER is a key driver of deep endometriosis. Progestin treatment was associated with a reduction of ER-α expression; however, failure of ER suppression by progestins was also a predictor of pain severity and recurrence at 1 year.

Unexpected Impact of a Hepatitis C Virus Inhibitor on 17β-Estradiol Signaling in Breast Cancer.

17β-Estradiol (E2) controls diverse physiological processes, including cell proliferation, through its binding to estrogen receptor α (ERα). E2:ERα signaling depends on both the receptor subcellular localization (e.g., nucleus, plasma membrane) and intracellular ERα abundance. Indeed, the control of ERα levels is necessary for the effects of E2, and E2 itself induces ERα degradation and cell proliferation in parallel. Thus, the modulation of intracellular ERα levels is a critical parameter for E2-induced cell proliferation. Therefore, we used this parameter as a bait to identify compounds that influence ERα levels and E2-dependent proliferation in breast cancer (BC) cells from a library of Food and Drug Administration (FDA)-approved drugs. We found that telaprevir (Tel) reduces ERα levels and inhibits BC cell proliferation. Tel is an inhibitor of the hepatitis C virus (HCV) NS3/4A serine protease, but its effect on E2:ERα signaling has not been investigated. Here, for the first time, we analyzed the effects of Tel on intracellular ERα levels and E2:ERα signaling to cell proliferation in different ERα-expressing BC cell lines. Overall, our findings demonstrate that Tel reduces intracellular ERα levels, deregulates E2:ERα signaling and inhibits E2-induced proliferation in BC cells and suggest the potential drug repurposing of Tel for the treatment of BC.

SUN-126 Distinct Molecular Phenotypes of Non-Diseased Breast Adipose Tissue of Pre-Menopausal Obese and Non-Obese Women May Underlie Differing Breast Cancer Risks

Obesity is a major risk factor for many chronic diseases including postmenopausal breast cancer. Paradoxically, breast cancer susceptibility is inversely linked to obesity in pre-menopausal women. Adipose tissues are active endocrine organs that play major roles in tumor development and progression; however, fat depots at different anatomical sites are biologically and functionally distinct and their singular influence on breast epithelial biology remains unclear. To study the early events by which breast adiposity may provide a microenvironment predisposing normal breast epithelial cells to tumorigenesis, we collected breast tissue from pre-menopausal (n=10/group) non-obese (NO, BMI=27.6±0.8) and obese (O, BMI=44.5±2.8) women of comparable ages (NO: 36.1± 3.3; O: 40.0±2.0) with no breast cancer and undergoing elective breast reduction surgery. Breast adipose tissue and corresponding glandular cells were analyzed histologically and evaluated for expression of genes (adipokines, cytokines, steroid hormone signaling) by QPCR and proteins (proliferation, apoptosis, inflammation) by IHC. Adipocyte size distributions from NO and O breasts did not differ (P=0.9). However, adipose mRNA levels for pro-inflammatory cytokines (IL-6, IL-8, CSF-1, MCP-1) and adipokines (LEP, CFD) were higher for O than NO (P<0.05). AdipoQ, ER-α, and ER-β transcript levels were lower for O than NO (P<0.05), while those for CYP19 and PTGS2 showed reverse trends (O>NO, P<0.05). In the corresponding glandular cells, NO had higher mRNA levels for IL-6, IL-8, ER-α, and ER-β than O (P<0.05). Immunostaining with anti-Ki67 antibodies indicated that O glandular cells were 3-fold less proliferative than those for NO, consistent with their lower Cyclin D1 mRNA levels (P<0.05). Galectin-1, a pro-fibrotic protein, showed predominant myo- vs. luminal epithelial localization, with staining intensities for O tending to be higher (P=0.07) than for NO. Perilipin immunostaining was specific for adipocytes and did not differ for O and NO. A non-targeted approach using a Human Cytokine Array (R&D Systems) was employed to further evaluate the inflammation status of O vs. NO adipose. The analyses confirmed the higher expression of IL-8, Leptin and CFD (by QPCR) in O vs. NO and identified C-reactive protein, EMMPRIN, Trefoil Factor-3, Cystatin-3 and Macrophage Migration Inhibitory Factor-1 as greater in O than NO (~2-fold). Our findings demonstrate marked differences in gene and protein expression patterns of O and NO breast adipose tissue, which were accompanied by a suppression of proliferation of O relative to NO breast epithelium. We speculate that early exposure of the breast epithelium to a highly inflammatory environment fueled by breast adiposity may promote a senescent state that confers protection from pre-menopausal breast cancer.

Impairment of learning and memory induced by perinatal exposure to BPA is associated with ERα-mediated alterations of synaptic plasticity and PKC/ERK/CREB signaling pathway in offspring rats

The effect of bisphenol A (BPA) on learning and memory has attracted much attention recently, but its underlying mechanism remains unclear. We aimed to investigate whether the impairment of learning and memory induced by perinatal exposure to BPA was associated with the hippocampal estrogen receptor α (ERα)-mediated synaptic plasticity and PKC/ERK/CREB signaling pathway in different sex offspring rats. Pregnant Sprague–Dawley rats were treated with BPA (1 and 10 μg/mL) through drinking water from gestational day (GD) 6 to postnatal day (PND) 21. After weaning, offspring drank BPA-free water until PND 56. Morris water maze, placement and object recognition, and step-down passive avoidance task were performed. The serum estradiol (E2) levels, histopathology of hippocampus, and the expression of learning and memory related proteins were measured. The results showed that spatial and recognition memory were impaired in BPA-exposed female and male offspring, but the impaired passive avoidance memory presented only in males, not in females. The serum E2 levels were increased in BPA-exposed females and males. BPA altered the morphology and quantity of hippocampal neurons. The levels of ERα, NMDA receptor subunit 2B (NR2B), p-NR2B, AMPA receptor 1 (GluA1), p-GluA1, PSD-95, synapsin I, PKC, p-ERK and p-CREB protein expression were decreased in BPA exposed females and males, and there were interactions of sex × BPA exposure in ERα, p-NR2B and p-ERK levels. These findings suggested that perinatal exposure to BPA has sex-specific effects on learning and memory, which is associated with ERα-mediated impairment of synaptic plasticity and down-regulation of PKC/ERK/CREB signaling pathway.

GPR30 Promotes the Phenotypic Switching of Vascular Smooth Muscle Cells via Activating the AKT and ERK Pathways.

BackgroundLower extremity varicose veins (LEVVs) are a common venous disorder of venous dilation and tortuosity. The functional integrity of vascular smooth muscle cells (VSMCs), the majority of the cells in venous tissues, and their phenotypic differences play important roles in the occurrence and development of LEVV. However, the underlying mechanism remains unclear.MethodsThe expression of estrogen receptors ERα and ERβ and G-protein-coupled receptor 30 (GPR30) in LEVV tissues and the role of GPR30 in VSMC phenotypic switching were examined by Western blotting and quantitative real-time PCR. Finally, the related mechanisms underlying LEVVs were explored by Western blotting.ResultsThe serum estradiol content was increased in LEVV patients compared with normal control patients, but the mRNA levels of ERα and ERβ were not significantly different. GPR30 was overexpressed in LEVVs, and high expression of GPR30 promoted the maintenance of a synthetic phenotype in which OPN, MMP-1 and MMP-9 were highly expressed and α-SMA was poorly expressed in VSMCs. Finally, the mechanism by which GPR30 promotes the phenotypic switching of VSMCs is dependent on the ERK1/2 and AKT pathways.ConclusionGPR30 may contribute to the pathogenesis of LEVVs by promoting the maintenance of a synthetic phenotype in VSMCs by activating the ERK1/2 and AKT pathways, and GPR30 might be a novel therapeutic target for clinical LEVV treatment.

Dysmenorrhea in patients with adenomyosis: A clinical and demographic study

ObjectiveTo identify the risk factors associated with dysmenorrhea in adenomyosis and to discuss the potential hormone-based understanding of pain mechanisms. Study designAdenomyosis patients with mild or no dysmenorrhea (n = 40, Group 1) and moderate-to-severe dysmenorrhea (n = 80, Group 2) were recruited. Charts of all patients were recorded. An immunohistochemistry (IHC) analysis was performed to detect the cellular levels of estrogen receptor-α (ER-α), estrogen receptor-β (ER-β), gonadotropin-releasing hormone receptor (GnRH-R), and neurofilaments (NFs) in 60 cases. ResultsA history of cesarean section (CS) was positively related to the degree of dysmenorrhea in adenomyosis (OR (95 % CI): 4.397 (1.371–14.104)). The ER-α levels in the eutopic endometrium (EUE) of Group 2 were higher than those in the ectopic endometrium (ECE) of Group 1. Group 2 had higher NF levels in the ECE than in the EUE. ConclusionA history of CS is a risk factor for adenomyosis with moderate-to-severe dysmenorrhea. For patients with adenomyosis, high ER-α levels in the EUE and high NF levels in the ECE may be related to moderate-to-severe dysmenorrhea. These hormone-based mechanisms may contribute to our understanding of the pathogenesis of dysmenorrhea in adenomyosis.

Estrogen Receptors and Endometriosis.

Endometriosis is a frequent and chronic inflammatory disease with impacts on reproduction, health and quality of life. This disorder is highly estrogen-dependent and the purpose of hormonal treatments is to decrease the endogenous ovarian production of estrogens. High estrogen production is a consistently observed endocrine feature of endometriosis. mRNA and protein levels of estrogen receptors (ER) are different between a normal healthy endometrium and ectopic/eutopic endometrial lesions: endometriotic stromal cells express extraordinarily higher ERβ and significantly lower ERα levels compared with endometrial stromal cells. Aberrant epigenetic regulation such as DNA methylation in endometriotic cells is associated with the pathogenesis and development of endometriosis. Although there is a large body of data regarding ERs in endometriosis, our understanding of the roles of ERα and ERβ in the pathogenesis of endometriosis remains incomplete. The goal of this review is to provide an overview of the links between endometriosis, ERs and the recent advances of treatment strategies based on ERs modulation. We will also attempt to summarize the current understanding of the molecular and cellular mechanisms of action of ERs and how this could pave the way to new therapeutic strategies.

Exercise Decreases Estrogen Receptor β and Inflammatory Cytokines in the Mesenteric Fat of an Endometriosis Rat Model

Endometriosis, a gynecological disorder, is characterized by increased levels of the estrogen receptor β (ERβ) in endometrial tissue. Estrogen receptors (ER) are also present in visceral fat and dysregulation of their function is known to correlate with increased white adipose tissue. Preliminary data in our lab found increased mesenteric fat and serum leptin levels in endometriosis animals, which are decreased by exercise. In rodents, morphology of the mesenteric fat can be regulated by exercise, however it is still unclear what role exercise plays in this change and how it might impact inflammatory conditions such as endometriosis.HypothesisVoluntary exercise can decrease endometriosis through modulation of ER in the mesenteric fat and a decrease in inflammatory cytokines.MethodsEndometriosis (ENDO) was induced in female Sprague Dawley rats by the implantation of uterine tissue next to the intestinal mesentery while control group (SHAM) received only sutures. The exercised endometriosis group (ENDO‐Ex) had access to a running wheel before and after surgery. After sixty days, rats were sacrificed and mesenteric fat was collected for measurement of ERβ, ERα, interleukin‐1β (IL‐1β), and interleukin‐6 (IL‐6) by RT‐PCR. After fixation and staining with hematoxylin &amp; eosin micro‐sections of mesenteric fat were analyzed to ascertain adipocyte morphology and their number and size.ResultsThe Endo animals had significantly higher amounts of mesenteric fat in contrast with the SHAM (p&lt;0.05) and the ENDO‐Ex animals (p&lt;0.01; n=9–10/group). The serum leptin hormone levels were significantly decreased in ENDO‐Ex animals when compared with the SHAM (p&lt;0.001) and ENDO (p&lt;0.001) animals. Across all groups a significant correlation was found between percentage of fat/body weight and ER‐β (p=0.011; n=12). Increased mesenteric fat also correlated with increased levels of IL‐1β (p=0.024) and IL‐6 (p=0.030) in the endometriosis animals (n=4/group). ENDO‐Ex animals developed less endometriotic lesions and these were smaller in size. Exercise significantly decreased ERβ levels (p=0.045) and IL‐1β (p=0.008, n=4/group) compared with ENDO. No significant differences were found in ERα levels between groups.ConclusionOur results demonstrate that exercise can reverse the increased levels of mesenteric fat, ERβ and inflammatory cytokines found in an animal model of endometriosis.Support or Funding InformationP20GM103475‐16, R15AT009915 &amp; R25GM096955

4-Hexylresorcinol Exhibits Different Characteristics to Estrogen

4-Hexylresorcinol (4HR) has been used as a food additive and antiseptic. The aim of this study was to evaluate whether the application of 4HR in breast cancer cells and ovariectomized rats showed estrogen-like effects. MCF-7 and SK-BR-3 cells were treated by solvent, 1–100 µM bisphenol-A (BPA), or 1–100 µM 4HR, respectively. 3-(4, 5-Dimethylthiazole-2-yl)- 2,5-diphenyltetrazolium bromide (MTT) assay and Western blot for extracellular signal-regulated kinase-1/-2 (ERK1/2), phosphorylated ERK1/2 (p-ERK1/2), estrogen receptor-α (ERα), and ERβ were done. As an in vivo study, ovariectomized rats (n = 15) received solvent, 125 mg/kg of 4HR, or 10 µg of 17-β estradiol via daily subcutaneous injection for 7 days. Blood samples were obtained for evaluation of prolactin levels. Pituitary glands and uteruses were biopsied for histological evaluation and Western blot analysis. Compared with the control group, the application of 4HR decreased the proliferation of MCF-7 and SK-BR-3 cells, while the application of BPA increased (p &lt; 0.05). The application of BPA increased the expression of ERα, ERβ, and p-ERK1/2, but 4HR did not change the expression of ERα, ERβ, or p-ERK1/2 in MCF-7 cells. In an animal model, the 4HR group showed similar levels of ERα, ERβ, and prolactin expression in the pituitary gland compared to the solvent only group, while the estradiol group showed higher levels. Serum prolactin levels were similar between the 4HR and solvent only groups. Taken together, 1–100 µM 4HR did not show BPA-like behavior in MCF-7 cells, and 125 mg/kg of 4HR daily subcutaneous injection for 7 days did not demonstrate estradiol-like effects in ovariectomized rats. Collectively, 4HR has no estrogen-like effects on both ERα-positive cells and estrogen-deficient rat models.