Search results for "estrogens"
showing 10 items of 160 documents
Effects of soy isoflavones on endothelial function in healthy postmenopausal women.
2005
Objective: To evaluate the effects of soy isoflavone administration on endothelial function in healthy postmenopausal women. Design: Sixty naturally postmenopausal women were randomly assigned to receive isoflavone or placebo tablets for 6 months. Endothelium-dependent vasodilatation was measured by brachial reactivity technique along with levels of plasma soluble intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, P-selectin and soluble thrombomodulin, von Willebrand factor, and tissue plasminogen activator. Differences between endothelium-dependent and endothelium-independent vasodilatation were assessed by evaluating brachial reactivity par…
Estradiol or genistein prevent Alzheimer's disease-associated inflammation correlating with an increase PPAR gamma expression in cultured astrocytes.
2009
Inflammation has been implicated in neurodegenerative disorders such as Alzheimer's disease (AD). The main inflammatory players in AD are the glial cells which initiate the inflammatory response. One of the earliest neuropathological changes in AD is the accumulation of astrocytes at sites of A beta deposition. It is desirable to find methods of tipping the balance towards anti-inflammatory state. Estrogenic compounds have shown anti-inflammatory and also antioxidant activity. Astrocytes were pretreated with 17-beta estradiol or with genistein, and 48 h later treated with 5 microM amyloid beta (A beta) for 24 h. We found that A beta induces inflammatory mediators, such as cyclooxygenase 2 (…
Steroid activities comparison of natural and food wrap compounds in human breast cancer cell lines
2004
Abstract In this study, we tested and compared the endocrine disruption activities of compounds in materials used to package foods (bisphenol A, bisphenol F, and bisphenol A diglycidylether BADGE) with natural molecules (genistein, apigenin, kaempferol, and tangeretin) in the human breast cancer cell lines MCF-7 (ER + ) and MDA-MB453 (AR + ; GR + ). Octylphenol was also chosen as a xenoestrogen reference. Two compounds had no estrogenic activity: BADGE and tangeretin. Genistein was the most active compound in the E-Screen assay with MCF-7, followed by octylphenol, bisphenol F, bisphenol A and apigenin, with kaempferol the least potent. All estrogenic compounds competed with 17β-estradiol fo…
Impact of estrogens on atherosclerosis and bone in the apolipoprotein E-deficient mouse model.
2014
Objective The common inflammatory pathophysiology has nourished the hypothesis of a relationship between osteoporosis and cardiovascular disease. Estrogens are key agents in the modulation of both processes. We investigated whether induction of atherosclerosis affects bone and whether estrogens modulate both processes. Methods Female apolipoprotein E-deficient mice (a well-established model of atherogenesis) were ovariectomized or falsely operated and fed either standard diet or high-fat diet (HFD). Six animals were included in each of the four groups. To clarify mechanisms, we treated preosteoblastic MC3T3-E1 cells with mouse serum. Results Physiological levels of estrogens in falsely oper…
Effects of Mn2+ on the responses induced by different spasmogens in the oestrogen-primed rat uterus
1997
Abstract We investigated the effect of Mn 2+ on the mechanical responses evoked by high K + (60 mM) or low Na + (25 mM) solutions, oxytocin and neurokinin A in the oestrogen-primed rat uterus. In a Ca 2+ -free, Mn 2+ (0.54 mM)-containing solution, high K + or low Na + solutions produced contractions of smaller amplitude than those observed in a normal Ca 2+ (0.54 mM) solution, which were abolished by nifedipine (1 μM). Oxytocin (1 μM) and neurokinin A (1 μM, in the presence of phosphoramidon 1 μM) evoked nifedipine-insensitive contractile responses similar to (oxytocin) or smaller (neurokinin A) in amplitude than those observed in Ca 2+ (0.54 mM)-containing solution. In strips loaded with C…
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…
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…
The Val432Leu polymorphism of the CYP1B1 gene is associated with differences in estrogen metabolism and bone density.
2009
Polymorphisms of the CYP450 genes that encode for the enzymes that metabolize estrogen are linked to hormone-related cancers. We investigated the impact of two polymorphisms of the CYP1B1 gene previously reported to be associated with hormone-related disorders on estrogen metabolism and bone mineral density (BMD), another hormone-dependent condition, in women from different ethnic backgrounds. Four hundred sixty-eight postmenopausal Caucasian women, 220 from St. Louis, MO, USA (mean age=63.5+/-0.53 years) and 248 from Palermo, Italy (mean age=72.9+/-0.44 years) participated in the study. Measurements of urinary estrogen metabolites by enzyme-linked immunoassay, serum estradiol by ultrasensi…
Genistein and endothelial function in postmenopausal women with metabolic syndrome
2013
BackgroundPrevious data have suggested that genistein could exert beneficial effects on endothelial function and on predictors of cardiovascular risk in healthy postmenopausal women. In a randomized clinical trial, we studied the effects of genistein on endothelial function in postmenopausal women with metabolic syndrome (MS). MethodsTwenty postmenopausal women with MS, according to modified NCEP-ATP III criteria were randomly assigned to receive placebo or genistein (54mg/day) for 6months, along with a Mediterranean-style diet. Postmenopausal women without MS (n=15), served as controls. The primary goal was the assessment of endothelial function by flow-mediated vasodilation (FMD) of brach…