18,358 research outputs found

    17,β-estradiol inhibits hepatitis C virus mainly by interference with the release phase of its life cycle

    Get PDF
    Rationale & Aim: Estrogen and estrogen-mediated signalling protect from hepatitis C virus through incompletely understood mechanisms. We aimed to ascertain which phase(s) of HCV life cycle is/are affected by estrogens. Methods: Huh7 cells infected with the JFH1 virus (genotype 2a) were exposed to dehydroepiandrosterone, testosterone, progesterone and 17β-estradiol (tested with/without its receptor antagonist fulvestrant). Dose-response curves were established to calculate IC50 values. To dissect how 17β-estradiol interferes with phases of HCV life cycle, its effects were measured on the HCV pseudo-particle system (viral entry), the sub-genomic replicon N17/JFH1 and the replicon cell line Huh7-J17 (viral replication). Finally, in a dual-step infection model, infectious supernatants, collected from infected cells exposed to hormones, were used to infect naïve cells. Results: Progesterone and testosterone showed no inhibitory effect on HCV; dehydroepiandrosterone was only mildly inhibitory. In contrast, 17β-estradiol inhibited infection by 64-67% (IC50 values 140 to 160 nM). Fulvestrant reverted the inhibition by 17β-estradiol in a dose-dependent manner. 17β-estradiol exerted only a slight inhibition (<20%) on HCV pseudo-particles, and had no effect on cells either transiently or stably (Huh7-J17 cells) expressing the N17/JFH1 replicon. In the dual-step infection model, a significant IC50 decline occurred between primary (134 nM) and secondary (100 nM) infections (p=0.02), with extracellular HCV RNA and infectivity being reduced to a higher degree in comparison to its intracellular counterpart. Conclusions: 17β-estradiol inhibits HCV acting through its intracellular receptors, mainly interfering with late phases (assembly/release) of the HCV life cycle

    The Major Pre- and Postmenopausal Estrogens Play Opposing Roles in Obesity-Driven Mammary Inflammation and Breast Cancer Development

    Get PDF
    Many inflammation-associated diseases, including cancers, increase in women after menopause and with obesity. In contrast to anti-inflammatory actions of 17β-estradiol, we find estrone, which dominates after menopause, is pro-inflammatory. In human mammary adipocytes, cytokine expression increases with obesity, menopause, and cancer. Adipocyte:cancer cell interaction stimulates estrone- and NFκB-dependent pro-inflammatory cytokine upregulation. Estrone- and 17β-estradiol-driven transcriptomes differ. Estrone:ERα stimulates NFκB-mediated cytokine gene induction; 17β-estradiol opposes this. In obese mice, estrone increases and 17β-estradiol relieves inflammation. Estrone drives more rapid ER+ breast cancer growth in vivo. HSD17B14, which converts 17β-estradiol to estrone, associates with poor ER+ breast cancer outcome. Estrone and HSD17B14 upregulate inflammation, ALDH1 activity, and tumorspheres, while 17β-estradiol and HSD17B14 knockdown oppose these. Finally, a high intratumor estrone:17β-estradiol ratio increases tumor-initiating stem cells and ER+ cancer growth in vivo. These findings help explain why postmenopausal ER+ breast cancer increases with obesity, and offer new strategies for prevention and therapy.This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 84510

    Influence of sex steroids on the viability and CD11b, CD18 and CD47 expression of blood neutrophils from dairy cows in the last month of gestation

    Get PDF
    In the period around parturition, cows experience an increased susceptibility for the development of Escherichia coli mastitis. This increased susceptibility has been correlated with a decreased functionality of neutrophils. In the current study, it is suggested that the decreased neutrophil functionality may be induced by the extensive alterations in sex steroid levels occurring around parturition. It was first hypothesized that 17 beta-estradiol and progesterone influence the viability, apoptosis and necrosis of blood neutrophils from cows in their last month of gestation. Subsequently, it was hypothesized that 17 beta-estradiol modulates the expression of CD11b, CD18 or CD47 thereby explaining its influence on the migration of bovine neutrophils. Neither 17 beta-estradiol nor progesterone significantly influenced viability, apoptosis or necrosis in spontaneous apoptosis conditions. However, when apoptosis was induced with TNF-alpha and gliotoxin, progesterone exerted a survival effect ( P < 0.05). In addition, 17 beta-estradiol treatment of bovine blood neutrophils significantly decreased the expression of CD47 ( P < 0.05) but not of CD11b or CD18. It can be concluded that 17 beta-estradiol and progesterone do not affect spontaneous apoptosis of bovine blood neutrophils while a survival effect was observed for progesterone on induced neutrophils apoptosis. Moreover, our results concerning the influence of 17 beta-estradiol on the CD11b, CD18 and CD47 expression extend previous demonstrations of the suppressive effect of 17 beta-estradiol on neutrophils migration and indicate that the altered expression of CD47 may contribute to this phenomenon

    Influence of 17 beta-estradiol, progesterone, and dexamethasone on diapedesis and viability of bovine blood polymorphonuclear leukocytes

    Get PDF
    The aim of the current study was to investigate whether polymorphonuclear leukocyte (PMN) diapedesis and viability are influenced by steroid hormones. Using an in vitro model with different types of cell layers ( bovine mammary epithelial cells and fibroblasts), we investigate whether steroid hormone treatments (17beta-estradiol, progesterone, and dexamethasone) have an influence on the diapedesis capacity and viability of PMN. In addition, we studied apoptosis of PMN in the in vitro model and evaluated the influence of different types of cell layers and steroid hormone treatments on this process. A significant decrease in the number of viable PMN in the lower compartment of the in vitro model (i.e., number of migrated PMN x viability after migration) was found after 17beta-estradiol treatment, whereas no influence was detected after progesterone or dexamethasone treatment. The effect of 17beta-estradiol was not due to a lower viability before migration as none of the treatments caused a significant effect on the viability before diapedesis. This treatment effect was not influenced by endogenous 17beta-estradiol or progesterone levels before isolation because there was no correlation between these plasma levels and PMN diapedesis capacity or viability. Furthermore, migration through epithelial cells caused a significant decrease in viability of PMN due to increased apoptosis but not necrosis

    Removal of endocrine disrupting chemicals using low pressure reverse osmosis membrane

    Get PDF
    Endocrine disrupting chemicals (EDCs) are one of the major focuses of contaminants in current environmental issues, as they can cause adverse health effects on animals and human, particularly to endocrine function. The objective of this study was to remove a specific group of EDCs (i.e molecular weight range 228 to 288 g/mol) using low pressure reverse osmosis membrane (LPROM). A multi-layer thin-film composite of aromatic polyamide (ES20) membrane and a C10-T cross flow module of LPROM manufactured by Nitto Denko Company was used in this study. The effects of operating parameters, i.e. pH, operating pressure, concentration and temperature were observed using a design of experiment based on MINITABTM software. The analysis of results was conducted by factorial analysis (FA) and response surface analysis (RSA). It was found that LPROM has been effectively applied to remove pentachlorophenol (PCP) (more than 83%), 17ß-estradiol (more than 87%) and bisphenol-A (BPA) (more than 87%). For permeate flux, both PCP and 17ß-estradiol tests produce excellent flux rate; i.e. 23.8 L/m2.h and 22.9 L/m2.h, respectively. For BPA, the permeate flux produced was slightly lower (19.1 L/m2.h) due to its physical-chemical properties effect at various levels of the recovery rate. In this study, the percentage of rejection was increased with the increased of pH and concentration of compounds. The flux was observed to increase with the increase of operating pressure. This study also investigated the interaction effects between operating parameters involved. In addition, statistical models were developed to represent the performance of LPROM under two response parameters, i.e. percentage of EDCs rejection and permeate flux. Statistical models were then validated using One-Factor-At-a-Time (OFAT) design of experiments and comparisons were made to better understand the trend of EDCs rejection and permeate flux

    Polyaniline entrapped water-dispersible 3mpa-znse quantum dots and their application for the development of an enzymatic electrochemical nanobiosensor for the detection of 17β-estradiol, an endocrine-disrupting compound

    Get PDF
    17β-estradiol is used as a growth and fertility stimulant in the agronomic sector to induce fertility and manipulate reproductive characteristics in animals. However, unintended or unregulated distribution and exposure to even significant low levels of 17β-estradiol estrogen have detrimental health implication that can lead to reproductive abnormalities and even cancer. This could have severe effect on the ecosystem imbalance, food safety, to such a degree that its health impact necessitates rapid methods to probe for its prevalence and occurrence in the environment. Herein a simple, robust, sensitive and once-off use electrochemical biosensor to detect 17β-estradiol is developed, using 3-mercaptopropionic acid capped zinc selenide quantum dots trapped within the polyaniline (PANI) framework structure. The biosensor’s interaction with the substrate was based on the capability of the hemeprotein, horseradish peroxidase (HRP) enzyme (i.e., baroreceptor) to alternatively catalyze phenolic alcohols. The biosensor displayed a significantly low limit of detection limit (LOD) of value 0.2 × 10−6 M towards 17β-estradiol. The Mechaelis-Menten constant (Km) with the magnitude of 0.64 × 10−6 M was obtained; this indicates an outstanding affinity of the biosensing films towards 17β-estradiol. Subsequently, the developed biosensor was able to accurately and efficiently measure successive concentrations of 17β-estradiol from 0.2 × 10 to 4 × 10−6 M. The fabricated biosensor showed good selectivity towards 17β-estradiol compared to the other estrogenic endocrine-disrupting compounds such as estrone (E1), ethnylstradiol (EE2), and estriol (E3). The biosensor was capable of detecting 17β-estradiol in spiked tap water samples with good recoveries, thus affirming its potential to be applied for real electro-analysis of 17β-estradiol in treated wastewater

    Novel locally active estrogens accelerate cutaneous wound healing-part 2

    Get PDF
    Estrogen deprivation is associated with delayed healing, while estrogen replacement therapy (ERT) accelerates acute wound healing and protects against development of chronic wounds. However, current estrogenic molecules have undesired systemic effects, thus the aim of our studies is to generate new molecules for topic administration that are devoid of systemic effects. Following a preliminary study, the new 17β-estradiol derivatives 1 were synthesized. The estrogenic activity of these novel compounds was evaluated in vitro using the cell line ERE-Luc B17 stably transfected with an ERE-Luc reporter. Among the 17β-estradiol derivatives synthesized, compounds 1e and 1f showed the highest transactivation potency and were therefore selected for the study of their systemic estrogenic activity. The study of these compounds in the ERE-Luc mouse model demonstrated that both compounds lack systemic effects when administered in the wound area. Furthermore, wound-healing experiments showed that 1e displays a significant regenerative and anti-inflammatory activity. It is therefore confirmed that this class of compounds are suitable for topical administration and have a clear beneficial effect on wound healing

    17β-estradiol Inhibits the Production of RANTES in Human Keratinocytes

    Get PDF
    A chemokine, regulated upon activation, normal T cell expressed and secreted (RANTES) attracts T helper-1 cells and macrophages. The production of RANTES is enhanced in keratinocytes of psoriatic skin lesions, which may contribute to the inflammatory infiltrate. It is known that estrogen regulates the natural course of psoriasis. We examined the in vitro effects of 17β-estradiol on RANTES production by human keratinocytes. 17β-estradiol inhibited tumor necrosis factor-α or interleukin-1β-induced RANTES secretion, mRNA expression, and promoter activity in keratinocytes, and these effects of 17β-estradiol were counteracted by estrogen receptor antagonist ICI 182 780. Two nuclear factor κB elements on RANTES promoter were required for tumor necrosis factor-α or interleukin-1β-induced transcription and involved in the inhibition by 17β-estradiol. 17β-estradiol inhibited nuclear factor κB transcriptional activity, whereas it did not inhibit DNA binding of nuclear factor κB or phosphorylation or degradation of the inhibitor of nuclear factor κB α in tumor necrosis factor-α or interleukin-1β-stimulated keratinocytes. 17β-estradiol-induced inhibition of nuclear factor κB transcriptional activity and RANTES promoter activity was rescued by overexpression of a coactivator cyclic AMP response element-binding protein (CREB) or nuclear factor κB p65 but not by steroid receptor coactivator-1 or nuclear factor κB p50. The overexpression of CREB-binding protein rescued 17β-estradiol-induced inhibition of transcription mediated by a chimeric protein, GAL4-p65286–551, which contained GAL4 DNA binding domain fused to C-terminal transactivating domain of p65 (amino acids 286–551). The transfection of estrogen receptor α or estrogen receptor β into estrogen receptor-negative SKBR3 cells resulted in 17β-estradiol-mediated inhibition of transcription via GAL4-p65286–551. These results suggest that 17β-estradiol-bound estrogen receptor may inhibit nuclear factor κB-dependent transcription of RANTES gene by competing with p65 for limiting amounts of CREB-binding protein

    The small heat shock protein B8 (HSPB8) modulates proliferation and migration of breast cancer cells

    Get PDF
    open12noBreast cancer (BC) is one of the major causes of cancer death in women and is closely related to hormonal dysregulation. Estrogen receptor (ER)-positive BCs are generally treated with anti hormone therapy using antiestrogens or aromatase inhibitors. However, BC cells may become resistant to endocrine therapy, a process facilitated by autophagy, which may either promote or suppress tumor expansion. The autophagy facilitator HSPB8 has been found overexpressed in some BC. Here we found that HSPB8 is highly expressed and differentially modulated by natural or synthetic selective ER modulators (SERMs), in the triple-positive hormone-sensitive BC (MCF-7) cells, but not in triple-negative MDA-MB-231 BC cells. Specific SERMs induced MCF-7 cells proliferation in a HSPB8 dependent manner whereas, did not modify MDA-MB-231 cell growth. ER expression was unaffected in HSPB8-depleted MCF-7 cells. HSPB8 over-expression did not alter the distribution of MCF-7 cells in the various phases of the cell cycle. Conversely and intriguingly, HSPB8 downregulation resulted in an increased number of cells resting in the G0/G1 phase, thus possibly reducing the ability of the cells to pass through the restriction point. In addition, HSPB8 downregulation reduced the migratory ability of MCF-7 cells. None of these modifications were observed, when another small HSP (HSPB1), also expressed in MCF-7 cells, was downregulated. In conclusion, our data suggest that HSPB8 is involved in the mechanisms that regulate cell cycle and cell migration in MCF-7 cells.openPiccolella, Margherita; Crippa, Valeria; Cristofani, Riccardo; Rusmini, Paola; Galbiati, Mariarita; Elena Cicardi, Maria; Meroni, Marco; Ferri, Nicola; Morelli, Federica F; Carra, Serena; Messi, Elio; Poletti, AngeloPiccolella, Margherita; Crippa, Valeria; Cristofani, Riccardo; Rusmini, Paola; Galbiati, Mariarita; Elena Cicardi, Maria; Meroni, Marco; Ferri, Nicola; Morelli, Federica F; Carra, Serena; Messi, Elio; Poletti, Angel

    Estrogenic activity of phenolic additives determined by an in vitro yeast bioassay

    Get PDF
    Copyright @ 2001 Environmental Health PerspectivesWe used a recombinant yeast estrogen assay to assess the activity of 73 phenolic additives that are used as sunscreens, preservatives, disinfectants, antioxidants, flavorings, or for perfumery. Thirty-two of these compounds displayed activity: 22 with potencies relative to 17 beta -estradiol, ranging from 1/3,000 to -estradiol. Forty-one compounds were inactive. The major criteria for activity appear to be the presence of an unhindered phenolic OH group in a para position and a molecular weight of 140-250 Da.This work was supported in part under contract with the U.K. Department of Trade and Industry as part of the Government Chemist Programme
    corecore