Search results for "Myometrium"
showing 10 items of 40 documents
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…
Beta3 adrenergic receptor stimulation in human macrophages inhibits NADPHoxidase activity and induces catalase expression via PPARγ activation
2017
IF 4.521; International audience; The beta3 adrenergic receptor (β3-AR) stimulation plays a protective role against preterm labor by blocking myometrial contraction, cytokine production, remodeling and apoptosis. We previously demonstrated that macrophage-induced ROS production in the myometrium was a key element leading to the induction of all these labor-associated features. We thus aimed to investigate if the β3-AR could be expressed in human macrophages and could trigger its protective role in the myometrium by directly inhibiting ROS production. Using lipopolysaccharide (LPS)-stimulated myometrial samples and cell co-culture experiments, we demonstrated that β3-AR stimulation inhibits …
Role of Stro1+/CD44+ stem cells in myometrial physiology and uterine remodeling during pregnancy†
2016
Regulation of myometrial functions during pregnancy has been considered the result of the integration of endocrine and mechanical signals. Nevertheless, uterine regeneration is poorly understood, and the cellular source within the gravid uterus is largely unexplored.In this study, we isolated and quantified the myometrial stem cells (MSC) population from pregnant female Eker rat uteri, by using Stro1/CD44 surface markers. We demonstrated that prior parity significantly increased the percentage of Stro1+/CD44+ MSC because of injured tissue response. Interestingly, we established that Stro1+/CD44+ MSC respond efficiently to physiological cues when they were treated in vitro under different do…
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…
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…
Stro-1/CD44 as putative human myometrial and fibroid stem cell markers
2015
Objective To identify and characterize myometrial/fibroid stem cells by specific stem cell markers in human myometrium, and to better understand the stem cell contribution in the development of uterine fibroids. Design Prospective, experimental human and animal study. Setting University research laboratory. Patient(s)/Animal(s) Women undergoing hysterectomy for treatment of symptomatic uterine fibroids and female NOD/SCID/IL-2Rγ null mice. Intervention(s) Identification and isolation of stem cells from human fibroids and adjacent myometrium tissues using Stro-1/CD44–specific surface markers. Main Outcome Measure(s) Flow cytometry, semiquantitative polymerase chain reaction, clonogenicity as…
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…
Effects of leptin on lipopolysaccharide-induced myometrial apoptosis in an in vitro human model of chorioamnionitis.
2011
Objective This study was aimed at assessing the role of leptin on human myometrium, by studying its receptor expression in pregnant myometrium and the interaction of leptin with inflammation-induced apoptosis. Study Design Myometrial samples were obtained from women with uncomplicated pregnancies who underwent cesarean delivery at term before labor onset. The effect of leptin on apoptosis was assessed by the incubation of myometrial strips with leptin (10 –10 to 10 –8 mol/L; 48 hours) before lipopolysaccharide treatment (10 μg/mL; 48 hours). Results Long and short leptin receptor isoforms were expressed in myometrial cells of pregnant women. Leptin prevented lipopolysaccharide-induced apopt…
Vitamin D as an effective treatment in human uterine leiomyomas independent of mediator complex subunit 12 mutation.
2021
Objective To study whether vitamin D (VitD) inhibits cell proliferation and Wnt/β-catenin and transforming growth factor−β (TGFβ) signaling pathways in uterine leiomyomas independent of mediator complex subunit 12 (MED12) mutation status. Design Prospective study comparing leiomyoma vs. myometrial tissues and human uterine leiomyoma primary (HULP) cells treated with or without VitD and analyzed by MED12 mutation status. Setting Hospital and university laboratories. Patient(s) Women with uterine leiomyoma without any treatment (n = 37). Intervention(s) Uterine leiomyoma and myometrium samples were collected from women undergoing surgery because of symptomatic leiomyoma pathology. Main Outcom…
Myofibroblasts Are Evidence of Chronic Tissue Microtrauma at the Endometrial-Myometrial Junctional Zone in Uteri With Adenomyosis.
2017
Background Adenomyosis (AM) uteri exhibit hyperperistalsis. The latter causes a chronic tissue trauma at the endometrial-myometrial junctional zone (EMJZ). Upon tissue trauma, microdehiscences in the myometrium facilitate the translocation of basal endometrial fragments into the myometrium. There, a metaplasia (mediated by transforming growth factor β1 [TGFβ1] and connective tissue growth factor [CTGF]) occurs and AM lesions develop. The abundance of myofibroblasts in a tissue hallmarks metaplasia and points to a tissue microtrauma. Materials and methods To study if myofibroblasts-as an evidence of tissue microtrauma-are more abundant at EMJZ in AM-uteri, a case-control experimental study w…