E-cigarettes increased the stopping rate as well as the reduction of daily cigarettes in participants who continued smoking. In fact, although all participants reported a significant reduction of tobacco consumption compared to the baseline, the use of e-cigarettes allowed smokers to achieve a better result. It could be worthwhile to associate this device with new ICT-driven models of self-management support in order to enable people to better handle behavioral changes and side effects. This is true for ready-to-quit smokers (such as our participants) but can also be advantageous for less motivated smokers engaged in clinical settings.
Estetrol (E4) is a natural human estrogen present at high concentrations during pregnancy. Due to its high oral bioavailability and long plasma half-life, E4 is particularly suitable for therapeutic applications. E4 acts as a selective estrogen receptor (ER) modulator, exerting estrogenic actions on the endometrium or the central nervous system, while antagonizing the actions of estradiol in the breast. We tested the effects of E4 on its own or in the presence of 17β-estradiol (E2) on T47-D ER+ breast cancer cell migration and invasion of three-dimensional matrices. E4 administration to T47-D cells weakly stimulated migration and invasion. However, E4 decreased the extent of movement and invasion induced by E2. Breast cancer cell movement requires a remodeling of the actin cytoskeleton. During exposure to E4, a weak, concentration-dependent, re-distribution of actin fibers toward the cell membrane was observed. However, when E4 was added to E2, an inhibition of actin remodeling induced by E2 was seen. Estrogens stimulate ER+ breast cancer cell movement through the ezrin–radixin–moesin family of actin regulatory proteins, inducing actin and cell membrane remodeling. E4 was a weak inducer of moesin phosphorylation on Thr558, which accounts for its functional activation. In co-treatment with E2, E4 blocked the activation of this actin controller in a concentration-related fashion. These effects were obtained through recruitment of estrogen receptor-α. In conclusion, E4 acted as a weak estrogen on breast cancer cell cytoskeleton remodeling and movement. However, when E2 was present, E4 counteracted the stimulatory actions of E2. This contributes to the emerging hypothesis that E4 may be a naturally occurring ER modulator in the breast.
Sex steroid hormones are fundamental regulators of cell growth, proliferation and migration. Oestrogens direct the development of tissues and organs (1) and orchestrate cell growth and proliferation during adult life (2). Cells respond to the environment through the expression of transmembrane receptors that sense extracellular stimuli and activate an elaborate network of intracellular signalling molecules. Given the large number of different signalling molecules and the complex relationships between them, a major challenge is to understand how specific signals generate unique responses. The architecture of signalling networks plays an important role in achieving signalling specificity (3).Cell morphology and its interaction with the extracellular environment requires a number of regulators orchestrating the different cytoskeletal components and their interactions with the cell membrane and anchorage proteins (4). Recent findings indicate that the extranuclear signalling of oestrogen is a fundamental regulator of cell morphology in diverse cellular lines, including neurones (5,6), and that many of these actions are played via rapid signalling to the actin cytoskeleton achieved via actin recruitment (7-11).The present review describes and discusses the current understanding of the regulatory actions of sex steroids on the cytoskeleton of neurones, with the aim of highlighting how these hormones influence the turnover of dendritic spines. Sex steroids and the brainThe brain is an important target of sex steroids that play multiple regulatory roles. These hormones are powerful mediators of dynamic brain differentiation into a male or female phenotype. This phenomenon has been originally described in studies on neuronal cell migration in the developing pre-optic area ⁄ anterior hypothalamus (12-15). The effects of sex hormones turn into differences in neuronal cell number, glial complexity, neurochemical expression Journal of NeuroendocrinologyCorrespondence to: T. Simoncini, Molecular and Cellular Gynecological Endocrinology Laboratory (MCGEL), Department of Reproductive Medicine and Child Development, Division of Obstetrics and Gynecology, University of Pisa, Via Roma, 57, 56100 Pisa, Italy (e-mail: tommaso.simoncini@ med.unipi.it).Cell morphology and its interaction with the extracellular environment are integrated processes involving a number of intracellular controllers orchestrating cytoskeletal proteins and their interaction with the cell membrane and anchorage proteins. Sex steroids are effective regulators of cell morphology and tissue organisation, and recent evidence indicates that this is obtained through the regulation of the actin cytoskeleton. Intriguingly, many of these regulatory actions related to cell morphology are achieved through the rapid, nonclassical signalling of sex steroid receptors to kinase cascades, independently from nuclear alteration of gene expression or protein synthesis. The identification of the mechanistic basis for these rapid actions on cell cytoskeleton has special relevance...
BackgroundSmoking is a global public health problem. For this reason, experts have called smoking dependence a global epidemic. Over the past 5 years, sales of electronic cigarettes, or e-cigarettes, have been growing strongly in many countries. Yet there is only partial evidence that e-cigarettes are beneficial for smoking cessation. In particular, although it has been proven that nicotine replacement devices may help individuals stop smoking and tolerate withdrawal symptoms, e-cigarettes’ power to increase the quitting success rate is still limited, ranging from 5% to 20% dependent on smokers’ baseline conditions as shown by a recent Cochrane review. Consequently, it is urgent to know if e-cigarettes may have a higher success rate than other nicotine replacement methods and under what conditions. Furthermore, the effects of the therapeutic setting and the relationship between individual characteristics and the success rate have not been tested. This protocol is particularly innovative, because it aims to test the effectiveness of electronic devices in a screening program (the COSMOS II lung cancer prevention program at the European Institute of Oncology), where tobacco reduction is needed to lower individuals’ lung cancer risks.ObjectiveThis protocol was designed with the primary aim of investigating the role of tobacco-free cigarettes in helping smokers improve lung health and either quit smoking or reduce their tobacco consumption. In particular, we aim to investigate the impact of a 3-month e-cigarettes program to reduce smoking-related respiratory symptoms (eg, dry cough, shortness of breath, mouth irritation, and phlegm) through reduced consumption of tobacco cigarettes. Furthermore, we evaluate the behavioral and psychological (eg, well-being, mood, and quality of life) effects of the treatment.MethodsThis is a prospective, randomized, placebo-controlled, double-blind, three-parallel group study. The study is organized as a nested randomized controlled study with 3 branches: a nicotine e-cigarettes group, a nicotine-free e-cigarettes group, and a control group. The study is nested in a screening program for early lung cancer detection in heavy smokers.ResultsThe study is open and is still recruiting.ConclusionsStopping or reducing tobacco consumption should be a main goal of any health organization. However, traditional antismoking programs are expensive and not always effective. Therefore, favoring a partial or complete shift to e-cigarettes in heavy smokers (eg, persons at high risk for a number of diseases) could be considered a moral imperative. However, before following this path, sound and reliable data on large samples and in a variety of contexts are required.Trial RegistrationClinicaltrials.gov NCT02422914; https://clinicaltrials.gov/ct2/show/NCT02422914 (Archived by WebCite at http://www.webcitation.org/6etwz1bPL)
Endothelial plasminogen activator inhibitor (PAI-1) controls vascular remodeling, angiogenesis and fibrinolysis. PAI-1 blood levels in women are related to estrogen. The aim of this study was to characterize the signaling pathways through which estrogen regulates PAI-1 in endothelial cells. Furthermore, we aimed to investigate whether PAI-1 is implicated in the control of endothelial migration by estrogen. Cultured human umbilical vein endothelial cells (HUVECs) and ovariectomized rats were used to test the effects of 17β-estradiol (E(2)) on PAI-1 expression and its role on endothelial migration. At physiological concentrations, E(2) increases the expression of PAI-1 in HUVEC within 6-12 h through activation of a signaling cascade initiated by estrogen receptor α and involving G proteins, phosphatidylinositol-3-OH kinase and Rho-associated kinase II. ROCK-II activation turns into an over-expression of c-Jun and c-Fos that is required for E(2)-induced expression of PAI-1. Estrogen-induced PAI-1 expression is implicated in HUVEC horizontal migration. PAI-1 regulation is found also in vivo, in female rats, where ovariectomy is associated with reduced PAI-1 expression, while estrogen replacement counteracts this change. In conclusion, E(2) increases PAI-1 synthesis in human endothelial cells and in rodent aorta through a G protein-initiated signaling that targets early-immediate gene expression. This regulatory pathway is implicated in endothelial cell migration. These findings describe new mechanisms of action of estrogens in the vessels, which may be important for vascular remodeling and hemostasis.
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