Estrogen Receptor mRNA Expression Research Articles

Estrogen signaling in the dorsal raphe regulates binge-like drinking in mice

Estrogens promote binge alcohol drinking and contribute to sex differences in alcohol use disorder. However, the mechanisms are largely unknown. This study aims to test if estrogens act on 5-hydroxytryptamine neurons in the dorsal raphe nucleus (5-HTDRN) to promote binge drinking. We found that female mice drank more alcohol than male mice in chronic drinking in the dark (DID) tests. This sex difference was associated with distinct alterations in mRNA expression of estrogen receptor α (ERα) and 5-HT-related genes in the DRN, suggesting a potential role of estrogen/ERs/5-HT signaling. In supporting this view, 5-HTDRN neurons from naïve male mice had lower baseline firing activity but higher sensitivity to alcohol-induced excitation compared to 5-HTDRN neurons from naïve female mice. Notably, this higher sensitivity was blunted by 17β-estradiol treatment in males, indicating an estrogen-dependent mechanism. We further showed that both ERα and ERβ are expressed in 5-HTDRN neurons, whereas ERα agonist depolarizes and ERβ agonist hyperpolarizes 5-HTDRN neurons. Notably, both treatments blocked the stimulatory effects of alcohol on 5-HTDRN neurons in males, even though they have antagonistic effects on the activity dynamics. These results suggest that ERs’ inhibitory effects on ethanol-induced burst firing of 5-HTDRN neurons may contribute to higher levels of binge drinking in females. Consistently, chemogenetic activation of ERα- or ERβ-expressing neurons in the DRN reduced binge alcohol drinking. These results support a model in which estrogens act on ERα/β to prevent alcohol-induced activation of 5-HTDRN neurons, which in return leads to higher binge alcohol drinking.

Analysis of arsenic-modulated expression of hypothalamic estrogen receptor, thyroid receptor, and peroxisome proliferator-activated receptor gamma mRNA and simultaneous mitochondrial morphology and respiration rates in the mouse.

Arsenic has been identified as an environmental toxicant acting through various mechanisms, including the disruption of endocrine pathways. The present study assessed the ability of a single intraperitoneal injection of arsenic, to modify the mRNA expression levels of estrogen- and thyroid hormone receptors (ERα,β; TRα,β) and peroxisome proliferator-activated receptor gamma (PPARγ) in hypothalamic tissue homogenates of prepubertal mice in vivo. Mitochondrial respiration (MRR) was also measured, and the corresponding mitochondrial ultrastructure was analyzed. Results show that ERα,β, and TRα expression was significantly increased by arsenic, in all concentrations examined. In contrast, TRβ and PPARγ remained unaffected after arsenic injection. Arsenic-induced dose-dependent changes in state 4 mitochondrial respiration (St4). Mitochondrial morphology was affected by arsenic in that the 5 mg dose increased the size but decreased the number of mitochondria in agouti-related protein- (AgRP), while increasing the size without affecting the number of mitochondria in pro-opiomelanocortin (POMC) neurons. Arsenic also increased the size of the mitochondrial matrix per host mitochondrion. Complex analysis of dose-dependent response patterns between receptor mRNA, mitochondrial morphology, and mitochondrial respiration in the neuroendocrine hypothalamus suggests that instant arsenic effects on receptor mRNAs may not be directly reflected in St3-4 values, however, mitochondrial dynamics is affected, which predicts more pronounced effects in hypothalamus-regulated homeostatic processes after long-term arsenic exposure.

Alterations in gonadotropin, prolactin, androgen and estrogen receptor and steroidogenesis-associated gene expression in gander testes in relation to the annual period

Physiological mechanisms of seasonal changes in testicular function in birds are not fully elucidated. The balance between androgens and estrogens and testis sensitivity for gonadotropin and gonadal steroids are still unclear. The aim of the study was to examine: (1) the changes in circulating and intra-testicular steroid hormone levels and their relationship; (2) the mRNA expression of testicular gonadotropin, prolactin (PRL), progesterone (P4), androgen, and estrogen receptors, and (3) key steroidogenesis processes-related genes with immunofluorescent localization of aromatase in gander testes during the annual period. Testes from ganders (n = 25) in the first reproduction season were obtained at five breeding stages, i.e., prebreeding (PrB), peak of reproduction (PR), postbreeding (PoB), nonbreeding (NB), and onset of reproduction (OR). Males were kept under breeding conditions. It was found that plasma P4 levels decreased at the PoB and NB stages, whereas intra-testicular P4 was the highest in the NB stage. Intra-testicular estradiol (E2) levels were higher at the PoB and NB stages than the other stages, whereas testosterone (T) levels showed a nearly opposite pattern. The plasma estradiol–to–testosterone ratios were higher at the PrB, PoB and NB stages compared to other stages. The transcript abundances for luteinizing hormone receptor (LHR), PRL receptor (PRLR), estrogen receptor alpha (ERα), and estrogen receptor beta (ERβ) also change in testicular tissue during the annual period. Moreover, StAR mRNA expression was upregulated at the PoB and NB stages, and CYP11A1 transcript level was the highest at the PoB stage. Stage-dependent changes in the CYP19A1 mRNA and aromatase protein levels with higher abundances of transcript at PoB and NB stages and protein at the NB stage were observed. Localization and immunofluorescent signal intensity for aromatase also differed in relation to the examined stages. It may be suggested that differential E2 levels, as well as aromatase expression and localization across annual stages are responsible for the seasonal activation/inactivation stages of testis spermatogenesis in domestic ganders. These data strongly suggest a role of aromatase in the control of gander steroidogenesis as changes in this enzyme level are associated with alternation in gonadal steroid hormones. In addition, joint action with others hormones, like PRL and LH, seems to be important in the final effect of seasonal reproduction potential.

Protective effects of genistein on the production performance and lipid metabolism disorders in laying hens with fatty liver hemorrhagic syndrome by activation of the GPER-AMPK signaling pathways.

The aim of this study was to evaluate the beneficial effects and potential mechanisms of genistein (GEN) on production performance impairments and lipid metabolism disorders in laying hens fed a high-energy and low-protein (HELP) diet. A total of 120 Hy-line Brown laying hens were fed with the standard diet and HELP diet supplemented with 0, 50, 100, and 200 mg/kg GEN for 80 d. The results showed that the declines in laying rate (P < 0.01), average egg weight (P < 0.01), and egg yield (P < 0.01), and the increase of the ratio of feed to egg (P < 0.01) induced by HELP diet were markedly improved by 100 and 200 mg/kg of GEN treatment in laying hens (P < 0.05). Moreover, the hepatic steatosis and increases of lipid contents (P < 0.01) in serum and liver caused by HELP diet were significantly alleviated by treatment with 100 and 200 mg/kg of GEN in laying hens (P < 0.05). The liver index and abdominal fat index of laying hens in the HELP group were higher than subjects in the control group (P < 0.01), which were evidently attenuated by dietary 50 to 200 mg/kg of GEN supplementation (P < 0.05). Dietary 100 and 200 mg/kg of GEN supplementation significantly reduced the upregulations of genes related to fatty acid transport and synthesis (P < 0.01) but enhanced the downregulations of genes associated with fatty acid oxidation (P < 0.01) caused by HELP in the liver of laying hens (P < 0.05). Importantly, 100 and 200 mg/kg of GEN supplementation markedly increased G protein-coupled estrogen receptor (GPER) mRNA and protein expression levels and activated the AMP-activated protein kinase (AMPK) signaling pathway in the liver of laying hens fed a HELP diet (P < 0.05). These data indicated that the protective effects of GEN against the decline of production performance and lipid metabolism disorders caused by HELP diet in laying hens may be related to the activation of the GPER-AMPK signaling pathways. These data not only provide compelling evidence for the protective effect of GEN against fatty liver hemorrhagic syndrome in laying hens but also provide the theoretical basis for GEN as an additive to alleviate metabolic disorders in poultry.

Age-dependent effects of estradiol on temporal memory: A role for the type 1 cannabinoid receptor?

This study investigated in male mice how age modulates the effects of acute 17β-estradiol (E2) on dorsal CA1 (dCA1)-dependent retention of temporal associations, which are critical for declarative memory. E2 was systemically injected to young (3–4 months old) and aged (22–24 months old) adult mice either (i) 1 h before the acquisition of an auditory trace fear conditioning (TFC) procedure allowing the assessment of temporal memory retention 24 h later or (ii) during in vivo electrophysiological recordings of CA3 to dCA1 synaptic efficacy under anesthesia. In young mice, E2 induced parallel dose-dependent reductions in memory and synaptic efficacy, i.e. an impairment in TFC retention and a long-term (NMDA receptor-dependent) depression of dCA1 synaptic efficacy as assessed by field excitatory postsynaptic potentials. In contrast, E2 tended to improved TFC retention whilst failing to change synaptic efficacy in aged mice. Age-dependent effects of E2 treatment were confirmed by immunohistochemical analyses of TFC acquisition-elicited dCA1 Fos activation. Thus, such an activation was respectively reduced and enhanced in young and aged E2-treated mice, compared to vehicle treatments. Hippocampal mRNA expression of estrogen receptors by RT-PCR analyses revealed an age-related increase in each receptor mRNA expression. In keeping with the key role of the endocannabinoid system in memory processes and CA3 to dCA1 synaptic plasticity, we next examined the role of cannabinoid type 1 receptors (CB1-R) in the aforementioned age-dependent effects of E2. Having confirmed that mRNA expression of CB1-R diminishes with age, we then observed that the deleterious effects of E2 on both memory and synaptic efficacy were both prevented by the CB1-R antagonist Rimonabant whilst being absent in CB1-R knock out mice. This study (i) reveals age-dependent effects of acute E2 on temporal memory and CA3 to dCA1 synaptic efficacy and (ii) suggests a key role of CB1-R in mediating E2 deleterious effects in young adulthood. Aging-related reductions in CB1-R might thus underlie E2 paradoxical effects across age.

Betulinic acid alleviates zearalenone-induced uterine injury in mice

Zearalenone (ZEA) is a mycotoxin with estrogen-like biological activity, which widely present in feed and raw materials, with strong reproductive system toxicity and a major threat to animal reproduction. Betulinic acid (BA) is a natural plant compound with antioxidant, anti-inflammatory and other pharmacological activities. However, the mechanism of ZEA-induced uterine injury and the protective effect of BA have not been reported. Our results show that ZEA could cause uterine histopathological damage and cellular ultrastructural damage, affecting the secretion of sex hormones, such as estradiol (E2) and progesterone (P4), and increase the mRNA and protein expression of estrogen receptor α (ERα). ZEA could inhibit the activities of catalase (CAT) and superoxide dismutase (SOD), increase the production of malondialdehyde (MDA) and reactive oxygen species (ROS), and cause uterine oxidative stress. Furthermore, ZEA affected the homeostasis of uterine cell proliferation and death by regulating the expression of proliferating cell nuclear antigen (PCNA) and activating the mitochondrial apoptotic pathway. ZEA-induced uterine injury might be related to the activation of p38/ERK MAPK signaling pathway. However, the regulatory effect of ZEA on the uterus was reversed after BA treatment. In conclusion, the uterus is an important target organ attacked by ZEA, and BA showed a good therapeutic effect.

Identification of neurohypophysial hormones and the role of VT in the parturition of pregnant seahorses (Hippocampus erectus).

Neurohypophysial hormones regulate the reproductive behavior of teleosts; however, their role in the gestation and parturition of ovoviviparous fishes with male pregnancy (syngnathids) remains to be demonstrated. In the present study, the complementary DNA (cDNA) sequences of arginine vasotocin (VT) and isotocin (IT) from the lined seahorse (Hippocampus erectus) were cloned and identified. We observed that the mature core peptides of seahorse VT and IT were conserved among teleosts. In the phylogenic tree, seahorse VT and IT were clustered independently with teleost VT and IT. The tissue distribution patterns of VT and IT were similar, and both were highly expressed in the brain, gills, and gonads. Interestingly, they were also expressed to some extent in the brood pouch. In situ hybridization revealed that VT and IT messenger RNA (mRNA) signals in the brain were mainly located in the preoptic area region of the hypothalamus. Intraperitoneal administration of the VT core peptide to pregnant seahorses induced premature parturition, stimulated gonadotropin release, increased serum estrogen levels, and decreased prolactin secretion. Moreover, VT injection upregulated the mRNA expression of the membrane estrogen receptor in the brood pouch. In summary, neurohypophysial hormones promote premature parturition by regulating estrogen synthesis through the hypothalamus–pituitary–gonad axis.

Anti-inflammatory and hemostatic effects of total extract, saponins, and flavonoids of Clinopodium chinense in female rats with abnormal uterine bleeding and mechanism

This study aims to explore the anti-inflammatory and hemostatic effects of the total extract of Clinopodium chinense(TEC), total saponins of C. chinense(TSC), and total flavonoids of C. chinense(TFC) in female rats with abnormal uterine bleeding(AUB), and the possible mechanism. Mifepristone(i.g., 12.4 mg·kg~(-1)) and misoprostol(i.g., 130 μg·kg~(-1)) were used to induce AUB in SD female rats conceiving on the same day. Then the AUB rats were randomized into model group, TEC group, TSC group, TFC group, Yimucao Granules(LG) group, and estradiol valerate(EV) group, with 8 rats in each group. Another 8 non-pregnant female rats were selected as normal group. During the experiment, each group was given the corresponding drug by gavage once a day for 7 days. After the administration, blood and uterine tissue were collected. The uterine bleeding volume was measured by ultraviolet spectrophotometry and the pathological changes of endometrium were observed based on hematoxylin-eosin(HE) staining. In addition, the microvessel density of endometrium was determined by immunohistochemistry, and the content of thromboxane B2(TXB2), 6-keto-PGF_(1α), interleukin-6(IL-6), and tumor necrosis factor-α(TNF-α) in plasma and levels of lutenizing hormone(LH), follicle stimulating hormone(FSH), estradiol(E_2), and progesterone in serum were detected by enzyme-linked immunosorbent assay(ELISA). The mRNA and protein expression of estrogenreceptor α(ERα), progesterone receptor(PR), matrix metalloproteinase(MMP)-2, MMP-9, and vascular endothelial growth factor(VEGF) in uterine tissue was determined by Western blot. Compared with the model group, TEC, TSC, and TFC can reduce uterine bleeding volume, alleviate the pathological damage of endometrium, and increase the microvessel density in endometrium. Moreover, TEC and TSC can significantly raise plasma TXB2 level and ratio of TXB2 to 6-keto-PGF_(1α), and TEC and TFC can significantly reduce the levels of IL-6 and TNF-α. In addition, TEC significantly elevated serum progesterone level and TFC significantly increased serum levels of E_2, FSH, and LH. TSC can significantly raise serum progesterone and FSH levels. In addition, TEC can significantly down-regulate the protein expression of PR, MMP-2, and VEGF and TSC significantly reduced the expression of MMP-9. TFC significantly decreased the expression of PR, MMP-9, and VEGF, and up-regulated the expression of ERα. In conclusion, TEC, TSC, and TFC all show therapeutic effects on AUB, particularly TEC. TSC exerts the effects by enhancing the coagulation function and promoting endometrial repair, and TFC by regulating estrogen levels and reducing inflammatory response. This study reveals the mechanism of C. chinense against AUB and also explains the holistic characteristics of Chinese medicine.

Abstract PD15-05: Assessment of estrogen receptor (ESR1) mRNA expression for prediction of extended aromatase inhibitor benefit in HR-positive breast cancer using NRG Oncology/NSABP B-42

Abstract Background: In NSABP B-14, the quantitative levels of ESR1 mRNA, assessed using the standardized 21-gene assay and qRT-PCR platform predicted tamoxifen benefit (interaction p-value &amp;lt;0.001). NSABP B-42 evaluated the effect of extended letrozole in postmenopausal women with hormone receptor-positive breast cancer who have completed 5 years of hormonal therapy with either an aromatase inhibitor or tamoxifen followed by an aromatase inhibitor. We proposed to determine if ESR1 mRNA, reported as the quantitative ER single gene score, is predictive of the magnitude of benefit from extended adjuvant endocrine therapy with letrozole in patients enrolled in NSABP B-42. Methods: This prospectively planned retrospective study used a stratified cohort sample drawn from the 2,589 B-42 patients with available tumor tissue blocks and appropriate consent. All 133 patients who experienced distant recurrence and 48 patients who experienced local/regional but not distant recurrence were included along with a stratified random sample of 547/2,408 patients without recurrence. The primary endpoint was distant recurrence. The primary analysis tested for the interaction between the continuous ER single gene score and the effect of extended letrozole treatment using a weighted Cox proportional hazards regression model. A secondary analysis considered the ER single gene score categorized using the prespecified cutoff of ≤9.1 versus &amp;gt;9.1. Recurrence-free interval was a secondary endpoint. Results: The results of the assay were available for 587 patients. The median ER score was 10.2 (IQR 9.3-11.0). There were 131 patients (23.2% weighted) with ER ≤9.1 and 456 (76.8% weighted) with ER &amp;gt;9.1. No significant interaction of the effect of extended letrozole treatment was found for either the ER single gene score (interaction hazard ratio letrozole vs. placebo with an IQR change in ER score 1.10, 95% CI 0.66 - 1.82, p=.72) or the categories ER ≤9.1 (treatment HR=0.40, 95% CI 0.15-1.06) or ER &amp;gt;9.1 (treatment HR=0.70, 95% CI 0.43-1.12) (interaction p=.32). There was also no apparent prognostic effect of the ER single gene score for distant recurrence with placebo treatment after 5 years of endocrine therapy (p=.12). Results were similar in analyses of any recurrence, analyses adjusting for the proliferation axis from the 21-gene assay, and subgroup analyses by nodal and HER2-status. Conclusions: The B-42 study provided no evidence that ESR1 mRNA as measured by the ER single gene score can inform decisions regarding extended letrozole therapy after 5 years of adjuvant endocrine therapy. Confidence intervals were relatively wide but rule out a strong predictive effect of the ER single gene score in the expected direction. Support: U10CA180868, -180822, U24CA196067; Novartis; Exact Sciences Citation Format: Eleftherios Mamounas, Hanna Bandos, Priya Rastogi, Michael R Crager, Carolyn Mies, Peter C Lucas, Charles E Geyer, Jr, Louis Fehrenbacher, Mark L Graham, Stephen KL Chia, Adam M Brufsky, Janice M Walshe, Gamini S Soori, Shaker R Dakhil, Soonmyung Paik, Sandra M Swain, Frederick L Baehner, Steven Shak, Norman Wolmark. Assessment of estrogen receptor (ESR1) mRNA expression for prediction of extended aromatase inhibitor benefit in HR-positive breast cancer using NRG Oncology/NSABP B-42 [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr PD15-05.

High expression of ERBB2 is an independent risk factor for reduced recurrence-free survival in patients with stage T1 non-muscle-invasive bladder cancer.

Molecular markers associated with breast cancer are assumed to be associated with outcome in non-muscle-invasive bladder cancer (NMIBC). We retrospectively investigated the association of the mRNA expression of estrogen receptor 1 (ESR1) and 2 (ESR2), progesterone receptor (PGR), MKI67, and HER2 (ERBB2) with recurrence-free (RFS), cancer-specific (CSS), and overall survival (OS) in 80 patients with stage T1 NMIBC. High expression of ESR2 (P = 0.003), ERBB2 (P < 0.001), and MKI67 (P = 0.029) was associated with shorter RFS. Only high ERBB2 was an independent prognostic factor for reduced RFS (HR = 2.98; P = 0.009). When sub stratifying the cohort, high ESR2 was associated with reduced RFS (P < 0.001), CSS (P = 0.037) and OS (P = 0.006) in patients without instillation therapy. High ESR2 was associated with reduced CSS (P = 0.018) and OS (P = 0.029) in females and with shorter RFS in both sexes (males: P = 0.035; females: P = 0.010). Patients with high ERBB2 showed reduced CSS (P = 0.011) and OS (P = 0.042) in females and reduced CSS (P = 0.012) in those without instillation, while RFS was significantly reduced irrespective of sex or instillation. High mRNA expression of ERBB2 is an independent predictor of reduced RFS in patients with stage T1 NMIBC. High ERBB2 and ESR2 are associated with reduced outcomes, especially in females and patients without instillation therapy.

Decreased Expression of Estrogen Receptors Is Associated with Tumorigenesis in Papillary Thyroid Carcinoma.

Papillary thyroid carcinomas (PTC), which is derived from thyroid follicular cells, is the most commonly differentiated thyroid cancer with sex disparity. However, the role of estrogen receptors (ERs) in the pathogenesis of PTC remains unclear. The present study aimed to determine the association of ER mRNA expression levels with clinicopathologic features in PTC. To that aim, the mRNA levels of ESR1 (ERα66), ESR1 (ERα36), ESR2, and G-protein-coupled estrogen receptor 1 (GPER1) in snap-frozen tissue samples from PTCs and adjacent normal thyroid tissues were determined using quantitative reverse transcription polymerase chain reaction (RT-qPCR), and the correlation between ER mRNA expression levels and clinicopathologic features was analyzed. The expression of ERα66, ERα36, ERβ, and GPER1 was lower in PTC specimens than in adjacent normal thyroid tissues. Moreover, low GPER1 expression was associated with extrathyroidal extension. There was no obvious difference in expression of ERs between PTC specimens from male and female patients. In conclusion, our findings highlight the importance of ERs in PTC tumorigenesis.

Effects of Estradiol on Expression of Estrogen Receptor and Collagen mRNAs in Chick Skin.

Skin thickness and strength differ between male and female chickens. This study aimed to clarify the effects of estradiol on the expression of estrogen receptors and collagen mRNA in chicken skin. Estradiol was administered to male chicks for 3 weeks, then cryosections of skin collected from the cervical, thoracic, dorsal, and pelvic limb regions were stained with hematoxylin and eosin, and dermal thickness was measured. Estrogen receptor and collagen mRNA expression was assessed using real-time RT-PCR, and collagen contents were determined. Estradiol did not alter dermal thickness or the collagen content of the skin from any tested region. Among the estrogen receptors, significantly more ESR1 mRNA was expressed in the thoracic skin of chicks administered with estradiol compared with vehicle (control), and in the thoracic skin compared with skin from other regions within each group. Estradiol did not affect ESR2, GPER, and COL1A1 mRNA expression. These results suggested that estradiol stimulates ESR1 expression in thoracic skin, but does not affect collagen synthesis in skin from any other region of male chicks.

Age-related alterations of gastric mucosa and estrogen synthesis in rat parietal cells.

The stomach has diverse functions other than gastric acid secretion. Multifaceted studies have investigated age-related changes of the gastrointestinal tract. Nevertheless, little is known about estrogen production changes in gastric parietal cells in rats aged over 3months. We investigated age-related changes in gastric estrogen synthesis and the accompanying changes in liver estrogen receptor from 3 to 24months. Weights of the body, stomach, and liver increased linearly from 3 to 18months, then maintained a constant proportion up to 24months. The gastric mucosa area (in mm2/1mm muscularis mucosa) showed a constant proportion throughout the rats' life. The population of parietal cells immunostained area with H+/K+-ATPase decreased gradually with advancing age. Cells that were immunopositive to aromatase antibody were observed at 3-24months. The expressions of aromatase mRNA and its protein were somewhat lower at 18 and 24months than at 3months. The portal venous estradiol concentration at 12months was 1.5 times higher than that at 3months, and that at 18months was a half of that at 3months. The expression of estrogen receptor mRNA in the liver at 18 and 24months was about 80% of that at 3months. Results suggest that the gastric estrogen production declines with aging, and the liver estrogen receptor is also affected accordingly. Simultaneously, the gastric mucosa continues to express aromatase to maintain liver function(s) throughout the animal's life.

Analysis of neuroendocrine factors in response to conditional stress in zebrafish Danio rerio (Cypriniformes: Cyprinidae)

Challenges in the aquatic environment disrupt the homeostasis mechanisms of many teleost fishes. Induction of stress affects the circulating levels of catecholamine and has an impact on development and reproduction. It is not known how osmotic and hypoxic stress could affect the catecholamine and serotonin levels in zebrafish despite its well-known action in the vertebrate brain. This study thus investigates how serotonin (5-HT), epinephrine (E), norepinephrine (NE), and dopamine (DA) in the brain of female zebrafish respond to hypoxic (air) and osmotic conditions (salinity of 10 ppt). Analysis of zebrafish brain utilizing HPLC with PDA detector using reverse-phase PrimeSep column indicated that osmotic stress, air response and its combination modified 5-HT, NE and E levels. The tested stressors elevated 5-HT (>2.8 μM) while lowering NE (<3.00 μM) and E (<1.02 μM) levels in the brain as opposed to exposure to non-stressed fish. In addition, reproductive markers such as vitellogenin (Vtg1) and estrogen receptor (ERα) mRNA expression in the brain were up-regulated after osmotic stress, whereas air exposure down-regulated ERα mRNA expression but up-regulated Vtg1 compared to non-stressed fish. Overall, the data indicate that acute osmotic stress and air exposure that lowered catecholamine E and NE and elevated 5-HT levels could up-regulate mRNA expression of ERα and Vtg1 genes in the zebrafish brain, thus presenting evidence for a role of neurotransmitters on reproductive signals during acute conditional stress in the brain of wild zebrafish.

Myocardial Expression of Estrogen Receptor-mRNA Is Associated With Lower Markers of Post-operative Organ Damage in Young Patients With Congenital Cardiac Defect.

Background: Estrogen receptors (ERs) relate to cardio-protection in adults, but their role in younger patients is not known. We aimed to assess the myocardial expression of ERα- and ERβ- mRNA in young patients with congenital cardiac disease and to analyze their putative protective role.Patients and Methods: Twenty children and young adults (seven females and 13 males) with a median age of 13.8 years (interquartile range: 12.3 years) were enrolled in this prospective study. The myocardial expression of ER-mRNA and genes involved in inflammation, growth, and stress response was assessed by real-time PCR and was correlated to post-operative (po) outcome.Results: ER-mRNA was detected in the myocardium of all patients, independently of gender and age. The expression of ER-mRNA correlated with that of mRNA coding for brain natriuretic peptide and for all cytokines tested. A higher ERα-mRNA expression correlated with lower troponin T concentrations at 24 h po (p = 0.032), higher PaO2/FiO2 ratio at 4 h po (p = 0.059), lower fluid retention at 4 h po (p = 0.048), and lower aspartate aminotransferase (AST) levels at 24 h po (p = 0.047). A higher ERβ-mRNA expression was also correlated with lower fluid retention at 24 h po (p = 0.048).Patients in whom the levels of ERα- and ERβ-mRNA were >P50 had lower troponin T (p = 0.003, respectively) and lower AST concentrations at 24 h po (p = 0.043, respectively) than the others.Conclusions: The expression of ERα- and ERβ-mRNA is present in the myocardium of children and young adults with congenital cardiac defect and is associated with lower markers of po organ damage. This suggests that ERs may provide perioperative organ protection in this population.

Anti-inflammatory activity of the Tongmai Yangxin pill in the treatment of coronary heart disease is associated with estrogen receptor and NF-κB signaling pathway

Ethnopharmacological relevanceThe Tongmai Yangxin Pill (TMYX) is a patented traditional Chinese medicine originating from two classic prescriptions, Zhigancao Decoction and Shenmai Yin, which composed of 11 Chinese medicinal herbs: Rehmannia glutinosa (Gaertn.) DC., Spatholobus suberectus Dunn, Ophiopogon japonicus (Thunb.) Ker Gawl., Glycyrrhiza uralensis Fisch., Polygonum multiflorum Thunb., Equus asinus L., Schisandra chinensis (Turcz.) Baill., Codonopsis pilosula (Franch.) Nannf., Chinemys reevesii (Gray), Ziziphus jujuba Mill. and Cinnamomum cassia (L.) J.Presl (Committee of the Pharmacopoeia of PR China, 2015). TMYX has marketed in China for the treatment of chest pain, palpitation, angina, irregular heartbeat and coronary heart disease (CHD) for several decades. Previous studies have confirmed that TMYX can treat CHD by reducing inflammation, but the underlying pharmacological mechanism remains unclear. Aim of the studyThis study aimed to declare the underlying pharmacological mechanism of anti-inflammatory activity of TMYX in the treatment of CHD via clinical trial, microarray study, bioinformatics analysis and the vitro assays. Materials and methodsEight CHD patients’ serum biochemical indices including coagulation function, lipid metabolism, endothelial injury, metalloprotease, adhesion molecule, inflammatory mediator and homocysteine were measured to investigate the reduction of CHD risk by TMYX oral administration (40 pills/time, 2 times/day) for eight weeks. The expression profile chips and Ingenuity Pathway Analysis (IPA) were assessed to reveal the global transcriptional response and predict related functions, diseases and canonical pathways. The in vitro anti-inflammatory actions of TMYX were evaluated using oxidized low-density lipoprotein (100 μg/mL) induced murine RAW264.7 macrophage with an ethanol extract from TMYX (EETMYX) (25–100 μg/mL). ResultsTMYX treatment showed reduced levels of apolipoprotein B, endothelin 1, nuclear factor κB (NF-κB) and homocysteine in CHD patients. In contrast, the treatment increased the ratio of apolipoprotein A/apolipoprotein B. EETMYX restored cell morphology and suppressed the lipid deposition of the induced foam cells. EETMYX exerted anti-inflammatory effects by raising the mRNA and protein expression of Estrogen receptor 1 (ESR1), blocking the reduction of IκBa level and the phosphorylation of IKKα/β, IκBα and NF-κB p65, accompanied by inhibiting MCP-1, TNF-α and IL-6 production, which were consistent with bioinformatics predictions. ConclusionTMYX treatment improved the biochemical indices in CHD patients. EETMYX effectively attenuated macrophage foam cell formation and exhibited anti-inflammatory activity is associated with regulating ESR1 and NF-κB signaling pathway activity.

Neuroendocrine patterns underlying seasonal song and year-round territoriality in male black redstarts

BackgroundThe connection between testosterone and territoriality in free-living songbirds has been well studied in a reproductive context, but less so outside the breeding season. To assess the effects of seasonal androgenic action on territorial behavior, we analyzed vocal and non-vocal territorial behavior in response to simulated territorial intrusions (STIs) during three life-cycle stages in free-living male black redstarts: breeding, molt and nonbreeding. Concurrently, we measured changes in circulating testosterone levels, as well as the mRNA expression of androgen and estrogen receptors and aromatase in the preoptic, hypothalamic and song control brain areas that are associated with social and vocal behaviors.ResultsTerritorial behavior and estrogen receptor expression in hypothalamic areas did not differ between stages. But plasma testosterone was higher during breeding than during the other stages, similar to androgen receptor and aromatase expression in the preoptic area. The expression of androgen receptors in the song control nucleus HVC was lower during molt when birds do not sing or sing rarely, but similar between the breeding and the nonbreeding stage. Nevertheless, some song spectral features and the song repertoire differed between breeding and nonbreeding. Territorial behavior and song rate correlated with the expression of steroid receptors in hypothalamic areas, and in the song control nucleus lMAN.ConclusionsOur results demonstrate seasonal modulation of song, circulating testosterone levels, and brain sensitivity to androgens, but a year-round persistency of territorial behavior and estrogen receptor expression in all life-cycle stages. This suggests that seasonal variations in circulating testosterone concentrations and brain sensitivity to androgens is widely uncoupled from territorial behavior and song activity but might still affect song pattern. Our study contributes to the understanding of the complex comparative neuroendocrinology of song birds in the wild.

Lipoxin A4 inhibits the development of endometriosis in a mouse model by suppressing local estradiol synthesis

We investigated whether lipoxin A4 (LXA4) inhibits the development of endometriosis by suppressing local estradiol synthesis. An endometriosis mouse model was constructed by surgical transplantation to subcutanous tissue sites. The treatment group received daily injections of LXA4 (10 μg/Kg) for 21days after which lesions were recovered. We measured 17β-HSD1, 17β-HSD2, CYP11A1, CYP19A1, CYP17A1, and estrogen receptor mRNA expression levels using real-time RT-PCR. In addition, immunohistochemistry was performed to determine protein expression and localization. After LXA4 administration, the volume of endometrial lesions was significantly reduced. Administration of LXA4 resulted in a more rudimentary architecture with a reduced number of developed glands surrounded by a small amount of stroma. LXA4 downregulated the mRNA and protein expression levels of 17β-HSD1, CYP11A1, CYP19A1, CYP17A1, ERα, and ERβ. Furthermore, LXA4 downregulated the expression of ERβ, aromatase expression, and 17β-HSD1 enzyme activity, which affected local estradiol production, resulting in reduced endometriosis. Results from our endometriosis mouse model showed that treatment with LXA4 reduced expression of enzymes and receptors associated or implicated with estrogen-dependent regulation of extra-uterine tissue. We believe that LXA4 has a potential therapeutic value for the treatment of endometriosis.

Low-magnitude vibration promotes osteogenesis of osteoblasts in ovariectomized osteoporotic rats via the estrogen receptor α

The purpose of this study was to investigate the effect of low-magnitude vibration on osteogenesis of osteoblasts in ovariectomized rats with osteoporosis via estrogen receptor α(ERα). The mRNA expression of osteogenic markers were examined with qRT-PCR, based on which the optimal vibration parameter for promoting osteogenesis was determined (45 Hz × 0.9 g, g = 9.8 m/s2). Then we loaded the optimal vibration parameter on the osteoblasts of ovariectomized rats with osteoporosis. The protein expression of osteogenic markers and ERα were detected with Western blot; the distribution of ERα was examined with immunofluorescence technique. Finally, through inhibiting the expression of ERα with estrogen receptor inhibitor ICI182780, the protein and mRNA expression of osteogenic markers were examined. First, the results showed that low-magnitude vibration could promote the expression of osteogenic markers and ERα in osteoblasts of ovariectomized rats with osteoporosis (P < 0.05), and make ERα transfer to the nucleus. On the other hand, the results also showed that after inhibiting the expression of ERα in osteoblasts of ovariectomized rats with osteoporosis, the protein and mRNA expression of osteogenic marker were decreased (P < 0.05). In our study, low-magnitude vibration played an important role in the osteogenesis of osteoblasts in ovariectomized rats with osteoporosis through increasing the expression and causing translocation of ERα. Furthermore, it provides a theoretical basis for the application of low-magnitude vibration in the prevention and treatment of postmenopausal osteoporosis.

Effects of repeated immobilization stress on hypothalamic-pituitary- ovarian axis in female rats

Objective: To explore the effects of repeated immobilization stress on hypothalamic-pituitary-ovarian axis in female rats. Methods: Forty female SD rats were randomly divided into two groups: control group (n=20) and experimental group (n=20). One group was fed normally, the other group was subjected to incremental load restraint stress. Brake stress once a day in the retainer (starting at 9: 00 a.m.), braking for 2 hours on the first day, increasing load by 0.5 hours a day for two weeks. Body weight, estrous cycle, sex hormone, organ coefficient, pathology and expression of related genes were detected to explore the harm of hypothalamic-pituitary-ovarian axis. Results: Repeated immobilization stress caused weight loss, prolonged estrous cycle, and changed the organ coefficient and morphology of ovaries and uterus. QPCR technique was used to detect the related genes. It was found that the expressions of gonadotropin releasing hormone, pituitary gonadotropin releasing hormone receptor, follicle stimulating hormone and luteinizing hormone mRNA were decreased significantly, while the expressions of ovarian follicle stimulating hormone and luteinizing hormone receptor mRNA were increased significantly. The expression of estrogen receptor mRNA in ovary and uterus was decreased significantly. Conclusion: Repeated immobilization stress may disrupt the estrous cycle by interfering with the endocrine regulation of the hypothalamic-pituitary-ovarian axis, thus damaging the gonadal and reproductive endocrine function of female animals.