The hormone estrogen is involved in both female and male reproduction, as well as numerous other biological systems including the neuroendocrine, vascular, skeletal, and immune systems. Therefore, it ...is also implicated in many different diseases and conditions such as infertility, obesity, osteoporosis, endometriosis, and a variety of cancers. Estrogen works through its two distinct nuclear receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). Various transcriptional regulation mechanisms have been identified as the mode of action for estrogen, mainly the classical mechanism with direct DNA binding but also a nongenomic mode of action and one using tethered or indirect binding. The expression profiles of ERα and ERβ are unique with the primary sites of ERα expression being the uterus and pituitary gland and the main site of ERβ expression being the granulosa cells of the ovary. Mouse models with knockout or mutation of Esr1 and Esr2 have furthered our understanding of the role of each individual receptor plays in physiology. From these studies, it is known that the primary roles for ERα are in the uterus and neuroendocrine system, as female mice lacking ERα are infertile due to impaired ovarian and uterine function, whereas female mice lacking ERβ are subfertile due to ovarian defects. The development of effective therapies for estrogen-related diseases has relied on an understanding of the physiological roles and mechanistic functionalities of ERα and ERβ in human health and disease.
ObjectiveIndirect evidence suggests that common genetic variation contributes to individual differences in antidepressant efficacy among individuals with major depressive disorder, but previous ...studies may have been underpowered to detect these effects.MethodA meta-analysis was performed on data from three genome-wide pharmacogenetic studies (the Genome-Based Therapeutic Drugs for Depression GENDEP project, the Munich Antidepressant Response Signature MARS project, and the Sequenced Treatment Alternatives to Relieve Depression STAR*D study), which included 2,256 individuals of Northern European descent with major depressive disorder, and antidepressant treatment outcomes were prospectively collected. After imputation, 1.2 million single-nucleotide polymorphisms were tested, capturing common variation for association with symptomatic improvement and remission after up to 12 weeks of antidepressant treatment.ResultsNo individual association met a genome-wide threshold for statistical significance in the primary analyses. A polygenic score derived from a meta-analysis of GENDEP and MARS participants accounted for up to approximately 1.2% of the variance in outcomes in STAR*D, suggesting a weakly concordant signal distributed over many polymorphisms. An analysis restricted to 1,354 individuals treated with citalopram (STAR*D) or escitalopram (GENDEP) identified an intergenic region on chromosome 5 associated with early improvement after 2 weeks of treatment.ConclusionsDespite increased statistical power accorded by meta-analysis, the authors identified no reliable predictors of antidepressant treatment outcome, although they did identify modest, direct evidence that common genetic variation contributes to individual differences in antidepressant response.
Background The frequencies, cellular phenotypes, epitope specificity, and clonal diversity of allergen-specific B cells in patients with food allergy are not fully understood but are of major ...pathogenic and therapeutic significance. Objective We sought to characterize peanut allergen–specific B-cell populations and the sequences and binding activities of their antibodies before and during immunotherapy. Methods B cells binding fluorescently labeled Ara h 1 or Ara h 2 were phenotyped and isolated by means of flow cytometric sorting from 18 patients at baseline and 13 patients during therapy. Fifty-seven mAbs derived from allergen-binding single B cells were evaluated by using ELISA, Western blotting, and peptide epitope mapping. Deep sequencing of the B-cell repertoires identified additional members of the allergen-specific B-cell clones. Results Median allergen-binding B-cell frequencies were 0.0097% (Ara h 1) or 0.029% (Ara h 2) of B cells in baseline blood from allergic patients and approximately 3-fold higher during immunotherapy. Five of 57 allergen-specific cells belonged to clones containing IgE-expressing members. Almost all allergen-specific antibodies were mutated, and binding to both conformational and linear allergen epitopes was detected. Increasing somatic mutation of IgG4 members of a clone was seen in immunotherapy, whereas IgE mutation levels in the clone did not increase. Conclusion Most peanut allergen–binding B cells isolated by means of antigen-specific flow sorting express mutated and isotype-switched antibodies. Immunotherapy increases their frequency in the blood, and even narrowly defined allergen epitopes are recognized by numerous distinct B-cell clones in a patient. The results also suggest that oral immunotherapy can stimulate somatic mutation of allergen-specific IgG4.
Abstract
Endometriosis is a gynecological disease that negatively affects the health of 1 in 10 women. Although more information is known about late stage disease, the early initiation of ...endometriosis and lesion development is poorly understood. Herein, we use a uterine tissue transfer mouse model of endometriosis to examine early disease development and its dependence on estradiol (E2) and estrogen receptor (ER) α within 72 hours of disease initiation. Using wild-type and ERα knockout mice as hosts or donors, we find substantial infiltration of neutrophils and macrophages into the peritoneal cavity. Examining cell infiltration, lesion gene expression, and peritoneal fluid, we find that E2/ERα plays a minor role in early lesion development. Immune-mediated signaling predominates E2-mediated signaling, but 48 hours after the initiation of disease, a blunted interleukin (IL)-6-mediated response is found in developing lesions lacking ERα. Our data provide evidence that the early initiation of endometriosis is predominantly dependent on the immune system, whereas E2/ERα/IL-6-mediated cross-talk plays a partial role. These findings suggest there are two phases of endometriosis—an immune-dependent phase and a hormone-dependent phase, and that targeting the innate immune system could prevent lesion attachment in this susceptible population of women.
A mouse model of endometriosis, used to examine the early initiation of disease, revealed that two phases of disease exist—an immune-predominant phase and hormone-predominant phase.
Clinically, developmental exposure to the endocrine disrupting chemical, diethylstilboestrol (DES), results in long-term male and female infertility. Experimentally, developmental exposure to DES ...results in abnormal reproductive tract phenotypes in male and female mice. Previously, we reported that neonatal DES exposure causes ERα-mediated aberrations in the transcriptome and in DNA methylation in seminal vesicles (SVs) of adult mice. However, only a subset of DES-altered genes could be explained by changes in DNA methylation. We hypothesized that alterations in histone modification may also contribute to the altered transcriptome during SV development. To test this idea, we performed a series of genome-wide analyses of mouse SVs at pubertal and adult developmental stages in control and DES-exposed wild-type and ERα knockout mice. Neonatal DES exposure altered ERα-mediated mRNA and lncRNA expression in adult SV, including genes encoding chromatin-modifying proteins that can impact histone H3K27ac modification. H3K27ac patterns, particularly at enhancers, and DNA methylation were reprogrammed over time during normal SV development and after DES exposure. Some of these reprogramming changes were ERα-dependent, but others were ERα-independent. A substantial number of DES-altered genes had differential H3K27ac peaks at nearby enhancers. Comparison of gene expression changes, H3K27ac marks and DNA methylation marks between adult SV and adult uterine tissue from ovariectomized mice neonatally exposed to DES revealed that most of the epigenetic changes and altered genes were distinct in the two tissues. These findings indicate that the effects of developmental DES exposure cause reprogramming of reproductive tract tissue differentiation through multiple epigenetic mechanisms.
•E2 induces non-genomic signals through membrane estrogen receptors.•Multiple models face challenges excluding strong nucleophilic ERα.•H2NES ERα exists only in cytoplasm and maintains E2-mediated ...rapid actions.•H2NES ERα does not activate E2-responsive endogenous genes.•H2NES ERα is a new experimental model for ERα mediated non-genomic actions.
Non-genomic effects of estrogen receptor α (ERα) signaling have been described for decades. However, the mechanisms and physiological processes resulting solely from non-genomic signaling are poorly understood. Challenges in studying these effects arise from the strongly nucleophilic tendencies of estrogen receptor, and many approaches to excluding ERα from the nucleus have been explored over the years. In this review, we discuss past strategies for studying ERα’s non-genomic action and current models, specifically H2NES ERα, first described by Burns et al. (2011). In vitro and preliminary in vivo data from H2NES ERα and H2NES mice suggest a promising avenue for pinpointing specific non-genomic ERα action.
Abstract Estrogen receptors (ERs) play a crucial role in reproduction and normal physiology. The two sub-types of ER (ERα and β) are expressed in various levels in different tissues and selective ...cell types. Gene targeting technology allowed us to produce lines of mice with disrupted ERα (αERKO) and ERβ genes (βERKO) as well as a compound αβERKO in the whole body. Male and female αERKO mice are infertile. Estrogen, EGF and IGF-1 treatments failed to induce uterine growth and DNA synthesis in αERKO uteri. αERKO females are infertile due to hypoplastic uteri and hyperemic ovaries with no corpora lutea due to persistent LH stimulation from loss of negative feedback. αERKO males are infertile, with testicular atrophy and seminiferous tubule dysmorphogenesis producing decreased spermatogenesis and inactive sperm. βERKO females show arrested folliculogenesis and subfertility. Ovarian analyses indicate differential gene expression related to ovulatory stimulation deficits including lack of LH, PR, Cyp19 and Cox2 expression. A unique ovarian phenotype is found only in αβERKO females showing transdifferentiation of granulosa cells to Sertoli cells. We describe here several novel mouse models which possess ERα gene modification. To understand ERα function in uterine endometrial epithelial cells, we generated a tissue selective ERα gene disrupted mouse model, the uterine epithelial-specific ERα knockout (UtEpiαERKO). To understand the physiological role of ERα functional domains, we generated a mouse model with a mutation in the ligand dependent transcription activation domain of ERα (AF2ERKI). Findings from the ERα mutant mice suggest that the absence of functional ERα is not lethal and results in significant endocrine effects and altered physiological processes.
The estrogen receptor (ER) is a ligand-dependent transcription factor containing two transcriptional activation domains. AF-1 is in the N terminus of the receptor protein and AF-2 activity is ...dependent on helix 12 of the C-terminal ligand-binding domain. Two point mutations of leucines 543 and 544 to alanines (L543A, L544A) in helix 12 minimized estrogen-dependent transcriptional activation and reversed the activity of the estrogen antagonists ICI182780 (ICI) and tamoxifen (TAM) into agonists in a similar manner that TAM activated WT ERα through AF-1 activation. To evaluate the physiological role of AF-1 and AF-2 for the tissue-selective function of TAM, we generated an AF-2–mutated ERα knock-in (AF2ERKI) mouse model. AF2ERKI homozygote female mice have hypoplastic uterine tissue and rudimentary mammary glands similar to ERα-KO mice. Female mice were infertile as a result of anovulation from hemorrhagic cystic ovaries and elevated serum LH and E2 levels, although the mutant ERα protein is expressed in the AF2ERKI model. The AF2ERKI phenotype suggests that AF-1 is not activated independently, even with high serum E2 levels. ICI and TAM induced uterotropic and ER-mediated gene responses in ovariectomized AF2ERKI female mice in the same manner as in TAM- and E2-treated WT mice. In contrast, ICI and TAM did not act as agonists to regulate negative feedback of serum LH or stimulate pituitary prolactin gene expression in a different manner than TAM- or E2-treated WT mice. The functionality of the mutant ERα in the pituitary appears to be different from that in the uterus, indicating that ERα uses AF-1 differently in the uterus and the pituitary for TAM action.
Estrogen receptor alpha (ERα) is a ligand‐dependent transcription regulator, containing two transactivation functional domains, AF‐1 and AF‐2. The selective estrogen receptor modulators (SERMs), ...including 4‐hydroxytamoxifen (4OHT), activate AF‐1 preferentially rather than AF‐2. However, it is unclear whether this specific function is related to the tissue‐selective functionality of SERMs. Moreover, there is no information determining AF‐1–dependent estrogenic‐genes existing in tissues. We sought to identify AF‐1–dependent estrogenic‐genes using the AF‐2 mutated knock‐in (KI) mouse model, AF2ERKI. AF2ER is an AF‐2 disrupted estradiol (E2)‐insensitive mutant ERα, but AF‐1–dependent transcription can be activated by the estrogen‐antagonists, fulvestrant (ICI) and 4OHT. Gene profiling and ChIP‐Seq analysis identified Klk1b21 as an ICI‐inducible gene in AF2ERKI uterus. The regulatory activity was analyzed further using a cell‐based reporter assay. The 5′‐flanking 0.4k bp region of Klk1b21 gene responded as an ERα AF‐1–dependent estrogen‐responsive promoter. The 150 bp minimum ERα binding element (EBE) consists of three direct repeats. These three half‐site sequences were essential for the ERα‐dependent transactivation and were differentially recognized by E2 and 4OHT for the gene activation. This response was impaired when the minimum EBE was fused with a thymidine‐kinase promoter but could be restored by fusion with the 100 bp minimum transcription initiation element (TIE) of Klk1b21, suggesting that the cooperative function of EBE and TIE is essential for mediating AF‐1–dependent transactivation. These findings provide the first in vivo evidence that endogenous ERα AF‐1 dominant estrogenic‐genes exist in estrogen‐responsive organs. Such findings will aid in understanding the mechanism of ERα‐dependent tissue‐selective activity of SERMs.
Approximately one-third of women Veterans Health Administration (VHA) users have substance use disorders (SUD). Early identification of hazardous substance use in this population is critical for the ...prevention and treatment of SUD. We aimed to understand challenges to identifying women Veterans with hazardous substance use to improve future referral, evaluation, and treatment efforts.
Design: We conducted a secondary analysis of semi-structured interviews conducted with VHA interdisciplinary women's SUD providers at VA Greater Los Angeles Healthcare System.
Using purposive and snowball sampling we interviewed 17 VHA providers from psychology, social work, women's health, primary care, and psychiatry.
Our analytic approach was content analysis of provider perceptions of identifying hazardous substance use in women Veterans.
Providers noted limitations across an array of existing identification methodologies employed to identify women with hazardous substance use and believed these limitations were abated through trusting provider-patient communication. Providers emphasized the need to have a process in place to respond to hazardous use when identified. Provider level factors, including provider bias, and patient level factors such as how they self-identify, may impact identification of women Veterans with hazardous substance use. Tailoring language to be sensitive to patient identity may help with identification in women Veterans with hazardous substance use or SUD who are not getting care in VHA but are eligible as well as those who are not eligible for care in VHA.
To overcome limitations of existing screening tools and processes of identifying and referring women Veterans with hazardous substance use to appropriate care, future efforts should focus on minimizing provider bias, building trust in patient-provider relationships, and accommodating patient identities.
Celotno besedilo
Dostopno za:
CEKLJ, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
