Search results for "Myometrium"

Dose-dependent biphasic leptin-induced proliferation is caused by non-specific IL-6/NF-κB pathway activation in human myometrial cells

2015

Background and Purpose Leptin, an adipokine synthesized by the placenta during pregnancy, has been proposed for the management of preterm labour (PTL), as it is able to prevent in vitro uterine contractility and remodelling associated with labour onset. Another common feature of labour onset is the phenotypic switch of myometrial smooth muscle cells from a proliferative to a hypertrophic state. As proliferative effects have been demonstrated for leptin in other tissues, we aimed to investigate its ability to induce myometrial proliferation and thus to maintain uterine quiescence. Experimental Approach We stimulated human primary myometrial smooth muscle cells with leptin in the presence or …

Effect of histamine and histamine analogues on human isolated myometrial strips.

1992

1. The effect of histamine and histamine H1- and H2-receptor agonists on isolated myometrium strips of premenopausal women has been examined. The effect of acetylcholine was also determined. 2. Histamine, 2-pyridylethylamine, 4-methylhistamine and acetylcholine, but not dimaprit, produced a concentration-related contractile response in human isolated myometrial strips. Histamine also produced a further contraction in human isolated myometrial strips precontracted with KCl (55 mM). 3. The contractile response to histamine was antagonized by the histamine H1-receptor antagonist, clemizole (0.1 microM) but was potentiated by the histamine H2-receptor antagonist, ranitidine (10 microM). Clemizo…

Inhibition of tumor cell proliferation in human uterine leiomyomas by vitamin D via Wnt/β-catenin pathway.

2018

To assess the effect of vitamin D (VitD) on human uterine leiomyomas through Wnt/β-catenin pathway inhibition, apoptosis induction, and cell growth arrest.A prospective study comparing leiomyoma vs. myometrium tissues. Paired design study comparing human uterine leiomyoma primary (HULP) cells treated with or without VitD.University hospital.Human uterine leiomyoma and myometrium were collected from women (aged 35-52 years) without hormonal treatment.Samples were collected from women undergoing surgery due to symptomatic uterine leiomyoma pathology.Uterine leiomyoma and myometrium tissues were analyzed by western blot (WB) to determine proliferation, Wnt/β-catenin, and apoptosis pathways. HU…

Die contraction Proteine (Actin-Myosin) im Uterusmuskel

1955

Nach einem kurzen Uberblick uber die Vorgange bei der Muskelkontraktion werden die Eigenschaften der contractilen Proteine dargestellt. Auf die gebrauchlichen Untersuchungsmethoden wird eingegangen, die fur die eigenen Untersuchungen angewandte viscosimetrische Methode ausfuhrlich wiedergegeben. Zwischen den contractilen Proteinen der Skelet- und der Uterusmuskulatur bestehen quantitative und qualitative Unterschiede. Auch andere fur den Kontraktionsprozes wichtige Faktoren verhalten sich in Skelet- und Uterusmuskulatur unterschiedlich. 27 menschliche Uteri, unter diesen 10 schwangere und 2 puerperale, wurden auf ihren Gehalt an contractilen Proteinen untersucht. Die Untersuchungsergebnisse…

Adult stem cells in the human endometrium

2009

Macrophage-induced reactive oxygen species promote myometrial contraction and labor-associated mechanisms

2020

AbstractAt labor, the myometrium is infiltrated by a massive influx of macrophages that secrete high levels of pro-inflammatory cytokines inducing the expression of specific labor-associated markers. However, the interactions between myocytes and macrophages and the role of macrophages in the myometrium at labor remain to be elucidated. In this work, we studied the role of myometrium-infiltrated macrophages and their interaction with myocytes in lipopolysaccharide-induced preterm labor. A co-culture model of human primary myometrial cells and macrophages was developed and validated. Collagen lattices were used to evaluate myocyte contraction. Differentiation steps were assessed by (i) phall…

Effects of Leptin on Lipopolysaccharide-Induced Remodeling in an In Vitro Model of Human Myometrial Inflammation1

2013

Reorganization of myometrial extracellular matrix (ECM) is essential for the uterus to achieve powerful synchronous contractions during labor. Remodeling of the ECM has been implicated in membrane rupture and cervical ripening. Because maternal obesity is associated with both delivery disorders and elevated circulating leptin levels, this study aimed to assess the ability of leptin to interfere with lipopolysaccharide (LPS)-induced myometrial ECM remodeling. Myometrial biopsy samples were obtained from women undergoing cesarean delivery before labor onset. Myometrial explants were incubated for 48 h with LPS and leptin. LPS challenge was associated with a marked decrease in collagen content…

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…

Lack of Hypoxic Response in Uterine Leiomyomas despite Severe Tissue Hypoxia

2008

Abstract Hypoxia is now established as a key factor influencing the pathophysiology of malignant growth. Among other effects, hypoxia modulates the expression of a multitude of genes through the induction of hypoxia-inducible transcription factors. This differential gene expression favors angiogenesis, cell survival, an invasive/metastatic phenotype, and resistance to anticancer therapies. Because benign tumors do not exhibit these traits, one might expect these entities to be neither hypoxic nor to induce the genetic hypoxia response program. To test this hypothesis, an investigation of the oxygenation status of 17 leiomyomas and 1 leiomyosarcoma of the uterus using polarographic needle el…

Optimized culture conditions for tissue explants of uterine leiomyoma

2012

Background Uterine leiomyomas are the most common benign tumours in women, which arise from smooth muscle cells of the uterine myometrium and usually are multicentric. In spite of their frequency pathogenesis is widely unknown, mainly due to the absence of a suitable model system. We describe the systematic optimization of culturing leiomyoma tissue explants in an economical and effective ex vivo system. Methods Different concentrations of oxygen, different media, sera, hormones, and growth factor supplements were tested. Immunohistochemical stainings with antibodies against hormone receptors as well as specifying proliferation and apoptotic indices and real-time PCR were performed. Results…