The aim of this study is the identification of direct endothelial regulation by the androgens testosterone (T) and dihydrotestosterone (DHT). We tested the effects of T and DHT on nitric oxide (NO) synthesis and on tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) expression in human endothelial cells and in ovariectomized (OVX) rats. The results showed that at physiological concentrations T and DHT increase endothelial synthesis of NO. This depends on a rapid recruitment of the extracellular-related kinase (ERK) 1/2 and of the phosphatidylinositol 3-OH kinase (PI3K)/Akt cascades, resulting in endothelial nitric oxide synthase (eNOS) Ser(1177)-phosphorylation. In addition, a later increase of eNOS expression is found. With supra-physiological amounts of T or DHT the induction of NO synthesis is lost. A concentration-related increase of t-PA expression starting from physiological concentrations of T or DHT is found, whereas PAI-1 is augmented only with higher doses. Although DHT exerts these actions through androgen receptors (AR), T acts in part through aromatase-dependent conversion to 17β-estradiol. Ovariectomy is associated with significant changes in eNOS, t-PA and PAI-1 expression in the aorta of Wistar rats and T and DHT result in modifications on eNOS, PAI-1 and t-PA that are in line with the in vitro experiments. In conclusion, T and DHT act on endothelial cells through AR or via conversion to estradiol. Physiological, but not higher amounts are associated with enhanced NO synthesis and an increased t-PA/PAI-1 ratio. These findings are useful to understand the impact of androgens in ageing individuals.
Purpose Pregnant women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection have a higher risk of hospitalization, admission to intensive care unit (ICU) and invasive ventilation, and of acute respiratory distress syndrome (ARDS). In case of ARDS and critical severe coronavirus disease 2019 (COVID-19), the use of extracorporeal membrane oxygenation (ECMO) is recommended when other respiratory support strategies (oxygen insufflation, non-invasive ventilation [NIV], invasive ventilation through an endotracheal tube) are insufficient. However, available data on ECMO in pregnant and postpartum women with critical COVID-19 are very limited. Methods A case series of three critically ill pregnant women who required ECMO support for COVID-19 in pregnancy and/or in the postpartum period. Results The first patient tested positive for COVID-19 during the second trimester, she developed ARDS and required ECMO for 38 days. She was discharged in good general conditions and a cesarean-section [CS] at term was performed for obstetric indication. The second patient developed COVID-19-related ARDS at 28 weeks of gestation. During ECMO, she experienced a precipitous vaginal delivery at 31 weeks and 6 days of gestation. She was discharged 1 month later in good general conditions. The third patient, an obese 43-year-old woman, tested positive at 38 weeks and 2 days of gestation. Because of the worsening of clinical condition, a CS was performed, and she underwent ECMO. 143 days after the CS, she died because of sepsis and multiple organ failure (MOF). Thrombosis, hemorrhage and infections were the main complications among our patients. Neonatal outcomes have been positive. Conclusion ECMO should be considered a life-saving therapy for pregnant women with severe COVID-19.
The new coronavirus emergency spread to Italy when little was known about the infection’s impact on mothers and newborns. This study aims to describe the extent to which clinical practice has protected childbirth physiology and preserved the mother–child bond during the first wave of the pandemic in Italy. A national population-based prospective cohort study was performed enrolling women with confirmed SARS-CoV-2 infection admitted for childbirth to any Italian hospital from 25 February to 31 July 2020. All cases were prospectively notified, and information on peripartum care (mother–newborn separation, skin-to-skin contact, breastfeeding, and rooming-in) and maternal and perinatal outcomes were collected in a structured form and entered in a web-based secure system. The paper describes a cohort of 525 SARS-CoV-2 positive women who gave birth. At hospital admission, 44.8% of the cohort was asymptomatic. At delivery, 51.9% of the mothers had a birth support person in the delivery room; the average caesarean section rate of 33.7% remained stable compared to the national figure. On average, 39.0% of mothers were separated from their newborns at birth, 26.6% practised skin-to-skin, 72.1% roomed in with their babies, and 79.6% of the infants received their mother’s milk. The infants separated and not separated from their SARS-CoV-2 positive mothers both had good outcomes. At the beginning of the pandemic, childbirth raised awareness and concern due to limited available evidence and led to “better safe than sorry” care choices. An improvement of the peripartum care indicators was observed over time.
Sex steroids play a key role in cell movement and tissue organization. Cell migration requires the integration of events that induce changes in cell structure such as protrusion, polarization and traction toward the direction of migration. These actions are driven by actin remodeling and are stabilized by the development of adhesion sites to extracellular matrix via transmembrane receptors linked to the actin cytoskeleton. Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that facilitates cell migration via the control of the turnover of focal adhesion complexes. In this work, we demonstrated that 17β-estradiol (E(2)) regulates actin remodeling and cell movement in human umbilical vein endothelial cells through the recruitment of FAK. E(2) induces phosphorylation of FAK and its translocation toward membrane sites where focal adhesion complexes are assembled. This process is triggered via a Gα/Gβ protein-dependent, rapid extra-nuclear signaling of estrogen receptor-α (ERα) that interacts in a multiprotein complex with c-Src, phosphatidylinositol 3-OH kinase and FAK. Phosphorylation of FAK is fundamental for its activation, translocation to the plasmatic membrane and the subsequent formation of focal adhesion complexes. In conclusion, we found that ERα enhances endothelial cell motility through the dynamic control of actin arrangement and the formation of focal adhesion complexes. The identification of these processes broadens the understanding of the actions of estrogens on endothelial cells and could be relevant in physiological or pathological settings.
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