Background: Decidualization (differentiation) of the endometrial stromal cells during the secretory phase of the menstrual cycle is essential for successful implantation. Transforming Growth Factor β1 (TGFβ1) canonically propagates its actions via SMAD signalling. A role for TGFβ1 in decidualization remains to be established and published data concerning effects of TGFβ1 on markers of endometrial decidualization are inconsistent.
View Article and Find Full Text PDFObjectives: To examine cervicovaginal elafin production in pregnancy and determine its relationship in bacterial vaginosis.
Study Design: Samples of cervicovaginal secretions were collected from women with uncomplicated singleton pregnancies (n = 112) below 20 weeks gestation. Bacterial flora was assessed using Nugent's criteria, and levels of elafin were measured by enzyme-linked immunosorbent serologic assay (ELISA).
The endometrial lining of the human uterus contains a population of phenotypically distinct (CD56(bright), CD16(dim)), tissue-specific, natural killer [uterine natural killer (uNK)] cells that play a key role in the establishment of a successful pregnancy. An increase in the number of endometrial uNK cells occurs when the conceptus implants, and there is a further increase during the early stages of placentation. Here, we describe studies that have identified human chorionic gonadotrophin (hCG), a glycoprotein synthesized by the preimplantation conceptus, as a novel regulator of uNK cell proliferation.
View Article and Find Full Text PDFC. trachomatis and C. abortus are related Gram-negative intracellular bacteria that cause reproductive failure due to infertility (C.
View Article and Find Full Text PDFTGFbeta1 is thought to be intimately involved in cyclic tissue remodeling and inflammatory events associated with menstruation. Menstruation is initiated by progesterone withdrawal; however, the underlying mechanisms are not well understood. In the present study, we have tested the hypothesis that locally produced TGFbeta1 may influence expression of progesterone receptor (PR) or the Wnt antagonist Dickkopf-1 (DKK) with consequential impact on regulation of menstruation.
View Article and Find Full Text PDFBackground: We have previously shown that the antigestagen mifepristone is contraceptive when given in a daily dose of 5 mg, po. Epidemiological studies suggest that gestagen-only contraceptives may increase the risk of transmission of human immunodeficiency virus (HIV) due to effects on the vaginal defenses to infection. We investigate the effects of mifepristone on vaginal thickness, steroid receptor and natural antimicrobial content and pharmacokinetics of mifepristone.
View Article and Find Full Text PDFObjective: The purpose of this study was to determine the expression of natural antimicrobials in primary cultured amnion epithelial cells and to examine their regulation by interleukin-1 beta (IL-1beta).
Study Design: Primary amnion epithelial cells were cultured from samples that were obtained at prelabor cesarean section (n = 12) and stimulated with IL-1beta. Natural antimicrobial messenger RNA expression was determined by real-time quantitative polymerase chain reaction, and protein was measured by enzyme-linked immunosorbent assay.
This review focuses on the complex events that occur in the endometrium after progesterone is withdrawn (or blocked) and menstrual bleeding ensues. A detailed understanding of these local mechanisms will enhance our knowledge of disturbed endometrial/uterine function--including problems with excessively heavy menstrual bleeding, endometriosis and breakthrough bleeding with progestin only contraception. The development of novel strategies to manage these clinically significant problems depends on such new understanding as does the development of new contraceptives which avoid the endometrial side effect of breakthrough bleeding.
View Article and Find Full Text PDFAt the beginning of the 21st century, community-based physicians have a technology which is safe, noninvasive and relatively inexpensive. It allows immediate access to visual data inside the body for the evaluation of health and disease. Prenatal ultrasound is vital for the efficient provision of preventive care even in community health centers, where physicians may not be the delivering physicians.
View Article and Find Full Text PDFIn women, endometrial morphology and function undergo characteristic changes every menstrual cycle. These changes are crucial for perpetuation of the species and are orchestrated to prepare the endometrium for implantation of a conceptus. In the absence of pregnancy, the human endometrium is sloughed off at menstruation over a period of a few days.
View Article and Find Full Text PDFBiochem Biophys Res Commun
May 2005
This study demonstrates a synergistic action of prostaglandin E and GM-CSF which causes the release of pro-tolerant cytokines in two monocyte cell lines: U937 and ML-1. The prostaglandin effect is cyclic AMP dependent since stimulators of adenyl cyclase such as forskolin (fsk) can replace PGE. Fsk and GM-CSF combinations raised messenger RNA for IL-10, interleukin-1 receptor antagonist (IL-1ra), and CD14 as well as the released proteins.
View Article and Find Full Text PDFAs infection influences the pathogenesis and presentation of celiac disease, we investigated the expression of natural antibiotics in this condition. Twenty-three adults were prospectively studied: 10 controls and 13 subjects with untreated celiac disease. Distal duodenal biopsies were taken at baseline and after 6 months of a gluten-free diet and assessed for the expression of natural antibiotics.
View Article and Find Full Text PDFContext: Progesterone acting via its cognate receptor is critical to maintaining a viable endometrial environment for implantation and pregnancy. During medical termination of pregnancy, the biological effect of progesterone is pharmacologically withdrawn and prostaglandins administered exogenously. Leukocytes within the uterus are the effector cells of an inflammatory response and play important roles in both tissue breakdown and remodeling.
View Article and Find Full Text PDFChlamydia/Chlamydophila are a family of intracellular gram-negative bacteria that infect their hosts primarily via mucosal epithelia. Chronic disease associated with bacterial persistence, inflammation and tissue damage are common sequelae of infection with these organisms. Human epithelial cell lines respond to infection by releasing pro-inflammatory cytokines and chemokines such as interleukin (IL)-6 and IL-8, and upregulating the expression of mRNA encoding Ikappa-Balpha, the endogenous inhibitor of NF-kappaB.
View Article and Find Full Text PDFObjective: Control of cervical function is poorly understood. The major structural component of the cervix is collagen and peri-partum cervical changes are largely due to the action of collagenase, either released by resident cells or derived from an influx of neutrophils. More importantly, the cell type that initiates the changes in the cervix is unknown although the resident fibroblast is a possible contender.
View Article and Find Full Text PDFThe key physiological function of the endometrium is preparation for implantation; and in the absence of pregnancy, menstruation and repair. The withdrawal of progesterone is the initiating factor for breakdown of the endometrium. The modulation of sex steroid expression and function with pharmacological agents has provided an invaluable tool for studying the functional responses of the endometrium to sex steroids and their withdrawal.
View Article and Find Full Text PDFThe human endometrium is an important site of innate immune defence, giving protection against uterine infection. Such protection is critical to successful implantation and pregnancy. Infection is a major cause of preterm birth and can also cause infertility and ectopic pregnancy.
View Article and Find Full Text PDFReprod Biomed Online
September 2003
Changes in human endometrium are essential to allow the establishment of pregnancy. These changes are induced in vivo by progesterone, and include appearance within the tissue of a specific uterine natural killer cell, characterized by an abundant expression of CD56. Changes also occur in the stromal cells, which undergo a characteristic decidualization reaction.
View Article and Find Full Text PDFBiochem Biophys Res Commun
October 2003
Elafin and secretory leukocyte protease inhibitor (SLPI) are anti-protease and anti-microbial molecules present at mucosal surfaces. Both molecules are expressed in the female reproductive tract where they may be involved in innate immune defence. This study examines the role of progesterone in the regulation of SLPI and elafin.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
September 2003
Elafin is an antiproteinase and antimicrobial molecule that is expressed at epithelial sites (for example, cervix). This study details the expression and regulation of elafin in the human endometrium. Elafin mRNA and protein expression were examined in endometrium throughout the menstrual cycle and in first-trimester decidua.
View Article and Find Full Text PDFbeta-Defensins are small cationic molecules that have antimicrobial actions against bacteria, fungi and viruses and contribute to mucosal immune responses at epithelial sites. The female reproductive tract is an important site of defensin production and innate defences are crucial to the preservation of fertility and successful pregnancy. This study details the expression of the recently characterized defensins, HBD3 and 4, in human endometrium.
View Article and Find Full Text PDFObjective: To determine the effect of hormonal contraception with a combined oral contraceptive pill and levonorgestrel intrauterine system on the expression of the natural antimicrobials secretory leukocyte protease inhibitor, beta-defensins 1 and 2, and granulysin in human endometrium.
Design: Observational study.
Setting: Day case ward in a department of obstetrics and gynecology.
Estrogen action is mediated via two subtypes of the estrogen receptor (ER), usually referred to as ERalpha and ERbeta. We have previously compared the spatial and temporal expressions of ERalpha and ERbeta proteins in human endometrium and reported that endothelial cells exclusively express ERbeta. In the present study we have extended our investigations to compare the pattern of expression of wild-type (ERbeta1) and a newly identified ERbeta variant isoform (ERbetacx/beta2) that lacks the ability to bind steroids.
View Article and Find Full Text PDFThe mechanisms which soften the cervix and allow it to dilate at birth are not well known. This is a crucial element in labour and current pharmacological approaches, largely the use of prostaglandins (PG), are only semi-selective for the cervix and can cause inappropriate myometrial contractions. Cervical ripening is accompanied by the influx of neutrophils, the neutrophil is a ready source of collagenase, and the cervix is dependent on collagen for its rigidity.
View Article and Find Full Text PDFHuman endometrium has a unique vascular architecture that allows menstruation, the shedding of a well-vascularised tissue layer, with limited bleeding. Blood loss is controlled at least in part by constriction of the perivascular cells, myofibroblasts that surround the spiral arterioles and have contractile activity. These perivascular cells, which are coupled to endothelial cells by processes, are responsive to changes in progesterone levels and express chemokines, cytokines and prostaglandins (PG) crucial to the control of leukocyte entry into endometrium.
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