Search results for "Estrogen"
showing 10 items of 530 documents
Raloxifene promotes prostacyclin release in human endothelial cells through a mechanism that involves cyclooxygenase-1 and -2
2005
Objective To examine the effects of raloxifene on prostacyclin production by human umbilical vein endothelial cells (HUVEC) and to shed light on the molecular details of that action. Design Cell culture for 4, 8, 16, 24, and 48 hours. Setting University research laboratory. Patient(s) Source of HUVEC. Intervention(s) Measurement of prostacyclin production and of protein levels and mRNA expression of cyclooxygenase (COX)-1 and -2. Main Outcome Measure(s) Prostacyclin production was measured by enzyme immunoassay, the mRNA expression of COX-1 was measured by quantitative real time-polymerase chain reaction, and the protein levels of COX-1 and -2 were measured by immunoblotting. Result(s) Ralo…
Vascular aging in women: is estrogen the fountain of youth?
2012
Aging is a physiological process associated with structural and functional changes in vasculature, including endothelial dysfunction, arterial stiffening and remodeling, impaired angiogenesis, and defective vascular repair, and with an increasing prevalence of atherosclerosis. The risk of cardiovascular disease differs between men and women, remaining lower in women during their fertile years and reaching values similar to their male peers after menopause. Menopause is marked by the loss of endogenous estrogen production. Therefore, estrogens have been implicated in premenopausal protection from cardiovascular disease, an assumption supported by experimental and some clinical studies, where…
Characteristics of histamine tachyphylaxis in rat uterine smooth muscle.
2002
Objective and design: To study both the desensitisation induced by short-term exposure to histamine and the mechanism responsible in the isolated rat uterus.¶Material: Precontracted isolated uterus (37 mM KCl) from oestrogenised Wistar rats were used.¶Treatment: Repetitive responses to histamine (10–6, 10–5, 10–4, 10–3 M), dimaprit and clonidine (10–4 M) were tested at 15, 30, 45 and 105 min., with their modifications by (5 mg/ kg, 24 h before sacrifice) reserpine, 10–7 M propranolol, 10–8 M atropine, and 10–6 M indomethacin. Dose-response curves for adrenaline were carried out as standard protocol.¶Methods: In vitro techniques (de Jalon's solution, 31°C, carbogen, isotonic registration, re…
Steroid Patterns of Benign Breast Disease
1990
We briefly review some biochemical aspects of benign breast disease (BBD), mainly focusing on free and conjugate estrogen content of breast cyst fluid (BCF), also in relation to cyst type. Evidence is reported that high K(+)-type I-cysts clearly associate with low Cl- levels and accumulate significantly higher quantities of dehydroepiandrosterone sulfate (DHAS) and estrone-3-sulfate (E1S). In spite of the limited number of cases, both increasing DHAS and E1S levels correlate with the increment of K+ to Na+ ratio. A positive correlation was also found between DHAS and E1S. Using electrochemical detection (ECD) on-line to high performance liquid chromatography (HPLC) in the reverse phase mode…
Cluster headache in relation to different age groups
2019
Cluster headache (CH) has always been considered a type of primary headache affecting predominantly male subjects in early and medium adulthood. However, recent studies carried out in large case series of patients with CH show that not infrequently it may set in also after age 50; by contrast, onset before adolescence is very rare. Additionally, when onset occurs before age 14 or from the sixth decade of life onward, male predominance decreases to the point that in chronic forms CH predominantly affects the female sex. This particular pattern of the gender ratio in relation to onset in different age groups suggests that hormonal factors may actually play a role in the genesis of CH. In part…
Neuroprotective Actions of Estradiol and Novel Estrogen Analogs in Ischemia: Translational Implications
2010
This review highlights our investigations into the neuroprotective efficacy of estradiol and other estrogenic agents in a clinically relevant animal model of transient global ischemia, which causes selective, delayed death of hippocampal CA1 neurons and associated cognitive deficits. We find that estradiol rescues a significant number of CA1 pyramidal neurons that would otherwise die in response to global ischemia, and this is true when hormone is provided as a long-term pretreatment at physiological doses or as an acute treatment at the time of reperfusion. In addition to enhancing neuronal survival, both forms of estradiol treatment induce measurable cognitive benefit in young animals. Mo…
Diacylglycerol kinase α mediatses 17-β-estradiol-induced proliferation, motility, and anchorage-independent growth of Hec-1A endometrial cancer cell …
2011
Increased levels of endogenous and/or exogenous estrogens are one of the well known risk factors of endometrial cancer. Diacylglycerol kinases (DGKs) are a family of enzymes which phosphorylate diacylglycerol (DAG) to produce phosphatidic acid (PA), thus turning off and on DAG-mediated and PA-mediated signaling pathways, respectively. DGK α activity is stimulated by growth factors and oncogenes and is required for chemotactic, proliferative, and angiogenic signaling in vitro. Herein, using either specific siRNAs or the pharmacological inhibitor R59949, we demonstrate that DGK α activity is required for 17-β-estradiol (E2)-induced proliferation, motility, and anchorage-independent growth of …
Alleles and haplotypes of the estrogen receptor alpha gene are associated with an increased risk of spontaneous abortion.
2010
Objective To investigate whether polymorphisms in estrogen receptor alpha (ERα) or beta (ERβ) genes are associated with a risk of miscarriage. Design A retrospectively analyzed, prospectively obtained database of cases and controls. Setting University hospital menopause unit. Patient(s) 177 women with at least one spontaneous abortion and 442 controls with at least one live birth and no history of miscarriage. Intervention(s) None. Main Outcome Measure(s) Genotype frequencies and odd ratios for abortion risk in cases and controls for four single nucleotide polymorphisms (SNPs) located in intron 1 (C>T and A>G), intron 4 (A>T), and exon 8 (T>C) for the ERα gene, and two SNPs located in intro…
Local Treatment of Urogenital Atrophy with an Estradiol-Releasing Vaginal Ring: A Comparative and a Placebo-Controlled Multicenter Study
1999
Local estrogen substitution has been shown to be more appropriate than any systemic application for the treatment of urogenital symptoms of hormone defiency. The efficacy, safety and acceptability of a new low-dose drug delivery system consisting of an estradiol-releasing silicone vaginal ring was studied in two multicenter trials. In an open-label comparative trial a total of 219 postmenopausal women were randomized to the estradiol-releasing vaginal ring or to estriol suppositories. In terms of efficacy both treatment arms were shown to be equivalent; however, significantly higher rates of acceptability were found for the vaginal ring. In a double-blinded placebo-controlled study a total …
The COMT val158met Polymorphism Is Associated with Early Pubertal Development, Height and Cortical Bone Mass in Girls
2005
Estrogens are involved in accretion of bone mass during puberty. Catechol-O-Methyltransferase (COMT) is involved in the degradation of estrogens. In this cross-sectional study we investigated associations between the COMT val158met polymorphism, which results in a 60-75% difference in enzyme activity between the val (high activity = H) and the met (low activity = L) variant, and skeletal phenotypes in 246 healthy pre/early pubertal girls. Girls with COMT(LL) were 5.4 cm taller than COMT(HH) girls. Dual x-ray absorptiometry showed higher values of bone mineral content (BMC), and larger areas of total body, femur and spine in COMT(LL). Cortical BMC, measured by peripheral quantitative compute…