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1.
Mol Immunol ; 157: 142-145, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37023493

RESUMEN

Environmental estrogens (EEs) are associated with an increased prevalence of asthma. These epigenetic alterations of the immune cells may explain the multigenerational effects on asthma development. We hypothesized that exposure to immune cells enhances allergic sensitization by initiating signaling in these cells. Human T cell lines (TIB-152, CCL-119) were exposed to varying concentrations of estradiol, bisphenol A, bisphenol S, or bisphenol A + estradiol. H3K27me3, phosphorylations of EZH2 (pEZH2), AKT (pAKT), and phosphatidylinositide 3-kinase (pPI3K) were assessed. pAKT and pPI3K were decreased in response to some of the concentrations of these exposures in both cell lines. It is likely that EEs exposure to immune cells is one of the factors in the increase in the prevalence of asthma.


Asunto(s)
Asma , Humanos , Estrógenos , Fenoles/toxicidad , Estradiol
2.
Steroids ; 168: 108411, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-31132367

RESUMEN

Ethinyl estradiol (EE2, the active component of many birth control formulations) persists in treated waste waters and it has become a concerning endocrine-disrupting contaminant throughout the world. Previous studies have not examined the behavior of EE2 in nongenomic signaling pathways and the subsequent functional responses (either alone or in mixtures) or conducted comparisons with the physiological estrogen estradiol (E2). In this study, mitogen-activated protein kinases (MAPKs), ERK, and JNK were activated in pituitary tumor cells by fM EE2, but p38 activation was insensitive to

Asunto(s)
Estradiol , Etinilestradiol , Equol
3.
Steroids ; 142: 84-93, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30012504

RESUMEN

Rapid nongenomic signaling by estrogens (Es), initiated near the cell membrane, provides new explanations for the potent actions of environmental chemicals that imperfectly mimic physiological Es. These pathways can affect tumor growth, stabilization, or shrinkage via a number of signaling streams such as activation/inactivation of mitogen-activated protein kinases and caspases, generation of second messengers, and phospho-triggering of cyclin instability. Though prostate cancers are better known for their responsiveness to androgen deprivation, ∼17% of late stage tumors regress in response to high dose natural or pharmaceutical Es; however, the mechanisms at the cellular level are not understood. More accurate recent measurements show that estradiol (E2) levels decline in aging men, leading to the hypothesis that maintaining young male levels of E2 may prevent the growth of prostate cancers. Major contributions to reducing prostate cancer cell numbers included low E2 concentrations producing sustained ERK phospho-activation correlated with generation of reactive oxygen species causing cancer cell death, and phospho-activation of cyclin D1 triggering its rapid degradation by interrupting cell cycle progression. These therapeutic actions were stronger in early stage tumor cells (with higher membrane estrogen receptor levels), and E2 was far more effective compared to diethylstilbestrol (the most frequently prescribed E treatment). Xenoestrogens (XEs) exacerbated the growth of prostate cancer cells, and as we know from previous studies in pituitary cancer cells, can interfere with the nongenomic signaling actions of endogenous Es. Therefore, nongenomic actions of physiological levels of E2 may be important deterrents to the growth of prostate cancers, which could be undermined by the actions of XEs.


Asunto(s)
Neoplasias de las Glándulas Endocrinas/metabolismo , Neoplasias de las Glándulas Endocrinas/patología , Estrógenos/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Transducción de Señal , Línea Celular Tumoral , Supervivencia Celular , Humanos , Masculino
4.
ACS Chem Neurosci ; 9(3): 514-521, 2018 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-29111677

RESUMEN

The 5-HT2A receptor (5-HT2AR) plays an important role in various neuropsychiatric disorders, including substance use disorder and schizophrenia. Homodimerization of this receptor has been suggested, but tools that allow direct assessment of the relevance of the 5-HT2AR:5-HT2AR homodimer in these disorders are necessary. We chemically modified the selective 5-HT2AR antagonist M100907 to synthesize a series of homobivalent ligands connected by ethylene glycol linkers of varying lengths that may be useful tools for probing 5-HT2AR:5-HT2AR homodimer function. We tested these molecules for 5-HT2AR antagonist activity in a cell line stably expressing the functional 5-HT2AR and quantified a downstream signaling target, activation (phosphorylation) of extracellular regulated kinases 1/2 (ERK1/2), in comparison to in vivo efficacy of altering spontaneous or cocaine-evoked locomotor activity in rats. All of the synthetic compounds inhibited 5-HT-mediated phosphorylation of ERK1/2 in the cellular signaling assay; the potency of the bivalent ligands varied as a function of linker length, with the intermediate linker lengths being the most potent. The Ki values for the binding of bivalent ligands to 5-HT2AR were only slightly lower than the values for the parent (+)-M100907 compound, but significant selectivity for 5-HT2AR over 5-HT2BR or 5-HT2CR binding was retained. In addition, the 11-atom-linked bivalent 5-HT2AR antagonist (2 mg/kg, intraperitoneally) demonstrated efficacy on par with that of (+)-M100907 in inhibiting cocaine-evoked hyperactivity. As we develop further strategies for ligand-evoked receptor assembly and analyses of diverse signaling and functional roles, these novel homobivalent 5-HT2AR antagonist ligands will serve as useful in vitro and in vivo probes of 5-HT2AR structure and function.


Asunto(s)
Calcio/metabolismo , Cocaína/farmacología , Receptor de Serotonina 5-HT2A/efectos de los fármacos , Antagonistas del Receptor de Serotonina 5-HT2/farmacología , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Receptor de Serotonina 5-HT2A/metabolismo , Transducción de Señal/efectos de los fármacos
5.
J Matern Fetal Neonatal Med ; 29(22): 3583-9, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26911979

RESUMEN

OBJECTIVE: The objective of this study is to determine if BPA exposure, as measured by maternal plasma (MP) and amniotic fluid (AF) BPA concentrations is associated with an increased risk of spontaneous preterm birth (PTB) and preterm premature rupture of membranes (pPROM). METHODS: In this nested case-control study, MP samples from women in term labor (n = 30), preterm labor that ended with preterm delivery (n = 25), or who had pPROM (n = 30) and amniotic fluid samples from term labor (n= 45), preterm labor (n = 60), and pPROM (n = 35) were assayed for BPA by enzyme immunoassay. RESULTS: BPA was detectible in 100% of MP and AF samples. Women with MP BPA concentrations in the fourth quartile were at increased risk of PTB (cOR = 4.12, 95% CI = 1.32-12.87; aOR = 4.78, 95% CI = 1.14-20) but not pPROM. High (fourth quartile) AF BPA values also tended to increase the risk of pPROM (cOR = 2.47, 95% CI = 0.96-6.37) but results were not statistically significant. CONCLUSIONS: Increased BPA concentration is associated with an increased risk for PTB or pPROM depending on the maternal-fetal compartment(s) affected. High MP plasma BPA concentrations are associated with PTB with intact membranes but high AF BPA concentrations may weakly be associated with pPROM.


Asunto(s)
Compuestos de Bencidrilo/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Ambientales/toxicidad , Rotura Prematura de Membranas Fetales/inducido químicamente , Fenoles/toxicidad , Nacimiento Prematuro/inducido químicamente , Adulto , Líquido Amniótico/química , Compuestos de Bencidrilo/análisis , Compuestos de Bencidrilo/sangre , Estudios de Casos y Controles , Estudios Transversales , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/análisis , Contaminantes Ambientales/sangre , Femenino , Rotura Prematura de Membranas Fetales/sangre , Humanos , Modelos Lineales , Modelos Logísticos , Fenoles/análisis , Fenoles/sangre , Embarazo , Nacimiento Prematuro/sangre , Factores de Riesgo
6.
Prostate ; 74(16): 1589-603, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25213831

RESUMEN

BACKGROUND: Diethylstilbestrol (DES) and other pharmaceutical estrogens have been used at ≥ µM concentrations to treat advanced prostate tumors, with successes primarily attributed to indirect hypothalamic-pituitary-testicular axis control mechanisms. However, estrogens also directly affect tumor cells, though the mechanisms involved are not well understood. METHODS: LAPC-4 (androgen-dependent) and PC-3 (androgen-independent) cell viability was measured after estradiol (E2) or DES treatment across wide concentration ranges. We then examined multiple rapid signaling mechanisms at 0.1 nM E2 and 1 µM DES optima including levels of: activation (phosphorylation) for mitogen-activated protein kinases, cell-cycle proteins, and caspase 3, necroptosis, and reactive oxygen species (ROS). RESULTS: LAPC-4 cells were more responsive than PC-3 cells. Robust and sustained extracellular-regulated kinase activation with E2 , but not DES, correlated with ROS generation and cell death. c-Jun N-terminal kinase was only activated in E2-treated PC-3 cells and was not correlated with caspase 3-mediated apoptosis; necroptosis was not involved. The cell-cycle inhibitor protein p16(INK4A) was phosphorylated in both cell lines by both E2 and DES, but to differing extents. In both cell types, both estrogens activated p38 kinase, which subsequently phosphorylated cyclin D1, tagging it for degradation, except in DES-treated PC-3 cells. CONCLUSIONS: Cyclin D1 status correlated most closely with disrupted cell cycling as a cause of reduced cell numbers, though other mechanisms also contributed. As low as 0.1 nM E2 effectively elicited these mechanisms, and its use could dramatically improve outcomes for both early- and late-stage prostate cancer patients, while avoiding the side effects of high-dose DES treatment.


Asunto(s)
Apoptosis/efectos de los fármacos , Dietilestilbestrol/farmacología , Estradiol/farmacología , Estrógenos/farmacología , Neoplasias de la Próstata/patología , Caspasa 3/metabolismo , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclina D1/metabolismo , Relación Dosis-Respuesta a Droga , Humanos , Masculino , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Estadificación de Neoplasias , Neoplasias de la Próstata/metabolismo , Especies Reactivas de Oxígeno/metabolismo
7.
Methods Mol Biol ; 1204: 123-33, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25182766

RESUMEN

We developed fixed-cell multi-well plate immunoassays that increase the throughput and ease of quantification for questions formerly assessed by immunoblot scanning. The assays make use of the now abundant antibodies designed to recognize receptor subtypes and posttranslationally modified signaling proteins. By optimizing permeabilization and fixation conditions, mainly based on specific cell types, the assay can be adapted to the study of many different antigens of importance to hormonal and neurotransmitter signaling scenarios.


Asunto(s)
Inmunoensayo/métodos , Sistema de Señalización de MAP Quinasas , Receptores de Estrógenos/análisis , Animales , Línea Celular , Células Cultivadas , Activación Enzimática , Pruebas de Enzimas/métodos , Humanos
8.
Sex Roles ; 70(5-6): 221-231, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24932061

RESUMEN

In the U.S., women account for over a quarter of the approximately 50,000 annual new HIV diagnoses and face intersecting and ubiquitous adversities including gender inequities, sexism, poverty, violence, and limited access to quality education and employment. Women are also subjected to prescribed gender roles such as silencing their needs in interpersonal relationships, which may lessen their ability to be resilient and function adaptively following adversity. Previous studies have often highlighted the struggles encountered by women with HIV without focusing on their strengths. The present cross-sectional study investigated the relationships of silencing the self and socioeconomic factors (education, employment, and income) with resilience in a sample of women with HIV. The sample consisted of 85 women with HIV, diverse ethnic/racial groups, aged 24 - 65 enrolled at the Chicago site of the Women's Interagency HIV Study in the midwestern region of the United States. Measures included the Connor-Davidson Resilience Scale -10 item and the Silencing the Self Scale (STSS). Participants showed high levels of resilience. Women with lower scores on the STSS (lower self-silencing) reported significantly higher resilience compared to women with higher STSS scores. Although employment significantly related to higher resilience, silencing the self tended to predict resilience over and above the contributions of employment, income, and education. Results suggest that intervention and prevention efforts aimed at decreasing silencing the self and increasing employment opportunities may improve resilience.

9.
Steroids ; 81: 36-42, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24269739

RESUMEN

Some chemicals used in consumer products or manufacturing (e.g. plastics, surfactants, pesticides, resins) have estrogenic activities; these xenoestrogens (XEs) chemically resemble physiological estrogens and are one of the major categories of synthesized compounds that disrupt endocrine actions. Potent rapid actions of XEs via nongenomic mechanisms contribute significantly to their disruptive effects on functional endpoints (e.g. cell proliferation/death, transport, peptide release). Membrane-initiated hormonal signaling in our pituitary cell model is predominantly driven by mERα with mERß and GPR30 participation. We visualized ERα on plasma membranes using many techniques in the past (impeded ligands, antibodies to ERα) and now add observations of epitope proximity with other membrane signaling proteins. We have demonstrated a range of rapid signals/protein activations by XEs including: calcium channels, cAMP/PKA, MAPKs, G proteins, caspases, and transcription factors. XEs can cause disruptions of the oscillating temporal patterns of nongenomic signaling elicited by endogenous estrogens. Concentration effects of XEs are nonmonotonic (a trait shared with natural hormones), making it difficult to design efficient (single concentration) toxicology tests to monitor their harmful effects. A plastics monomer, bisphenol A, modified by waste treatment (chlorination) and other processes causes dephosphorylation of extracellular-regulated kinases, in contrast to having no effects as it does in genomic signaling. Mixtures of XEs, commonly found in contaminated environments, disrupt the signaling actions of physiological estrogens even more severely than do single XEs. Understanding the features of XEs that drive these disruptive mechanisms will allow us to redesign useful chemicals that exclude estrogenic or anti-estrogenic activities.


Asunto(s)
Congéneres del Estradiol/farmacología , Congéneres del Estradiol/toxicidad , Transducción de Señal/efectos de los fármacos , Animales , Compuestos de Bencidrilo/farmacología , Caveolina 1/metabolismo , Mezclas Complejas/farmacología , Receptor alfa de Estrógeno/metabolismo , Estrona/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Fenoles/farmacología , Hipófisis/citología , Ratas
10.
Environ Health ; 12: 26, 2013 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-23530988

RESUMEN

BACKGROUND: Our study examines the effects of xenoestrogen mixtures on estradiol-induced non-genomic signaling and associated functional responses. Bisphenol-A, used to manufacture plastic consumer products, and nonylphenol, a surfactant, are estrogenic by a variety of assays, including altering many intracellular signaling pathways; bisphenol-S is now used as a bisphenol-A substitute. All three compounds contaminate the environment globally. We previously showed that bisphenol-S, bisphenol-A, and nonylphenol alone rapidly activated several kinases at very low concentrations in the GH3/B6/F10 rat pituitary cell line. METHODS: For each assay we compared the response of individual xenoestrogens at environmentally relevant concentrations (10-15 -10-7 M), to their mixture effects on 10-9 M estradiol-induced responses. We used a medium-throughput plate immunoassay to quantify phosphorylations of extracellular signal-regulated kinases (ERKs) and c-Jun-N-terminal kinases (JNKs). Cell numbers were assessed by crystal violet assay to compare the proliferative effects. Apoptosis was assessed by measuring caspase 8 and 9 activities via the release of the fluorescent product 7-amino-4-trifluoromethylcoumarin. Prolactin release was measured by radio-immunoassay after a 1 min exposure to all individual and combinations of estrogens. RESULTS: Individual xenoestrogens elicited phospho-activation of ERK in a non-monotonic dose- (fM-nM) and mostly oscillating time-dependent (2.5-60 min) manner. When multiple xenoestrogens were combined with nM estradiol, the physiologic estrogen's response was attenuated. Individual bisphenol compounds did not activate JNK, while nonylphenol did; however, the combination of two or three xenoestrogens with estradiol generated an enhanced non-monotonic JNK dose-response. Estradiol and all xenoestrogen compounds induced cell proliferation individually, while the mixtures of these compounds with estradiol suppressed proliferation below that of the vehicle control, suggesting a possible apoptotic response. Extrinsic caspase 8 activity was suppressed by estradiol, elevated by bisphenol S, and unaffected by mixtures. Intrinsic caspase 9 activity was inhibited by estradiol, and by xenoestrogen combinations (at 10-14 and 10-8 M). Mixtures of xenoestrogens impeded the estradiol-induced release of prolactin. CONCLUSIONS: In mixtures expected to be found in contaminated environments, xenoestrogens can have dramatic disrupting effects on hormonal mechanisms of cell regulation and their downstream functional responses, altering cellular responses to physiologic estrogens.


Asunto(s)
Contaminantes Ambientales/toxicidad , Estrógenos/metabolismo , Estrógenos/toxicidad , Hipófisis/efectos de los fármacos , Animales , Compuestos de Bencidrilo/toxicidad , Línea Celular , Proliferación Celular/efectos de los fármacos , Estradiol/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Fenoles/toxicidad , Fosforilación , Ratas , Transducción de Señal , Sulfonas/toxicidad
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