Biomedical subjects

Hilary O D Critchley

Publications and source records attributed to Hilary O D Critchley.

At least 19 recordsLinked to original sources

PubMed2006

Mifepristone-induced amenorrhoea is associated with an increase in microvessel density and glucocorticoid receptor and a decrease in stromal vascular endothelial growth factor.

BACKGROUND: We have previously shown that the progesterone antagonist mifepristone is a contraceptive when given in a dose of 2 or 5 mg per day. The majority of women experience amenorrhoea rather than the irregular break through bleeding usually occurring with other estrogen-free contraceptive pills, such as progestogen-only pill (POP). We investigated the effects of low-dose mifepristone on endometrial parameters which may be associated with changes in endometrial function, such as microvasculature, vascular endothelial growth factor (VEGF) and glucocorticoid receptor (GR) content. METHODS AND RESULTS: Endometrial biopsies were collected from 16 women before (late proliferative phase) and 60 and 120 days after taking 2 or 5 mg mifepristone daily for 120 days. Seven of the eight women who received 2 mg mifepristone and all eight women who received 5 mg were amenorrhoeic during the study. Mean estradiol (E(2)) concentrations remained in the mid-proliferative range, and the majority (9/16) of women showed proliferative endometrial histology at 60 and 120 days following treatment. There was a significant increase in the density of the endometrial stroma (P < 0.05) and microvessels (P < 0.01) following 120 days of treatment. Immunocytochemistry showed that GR, hitherto localized specifically in endometrial stroma, was up-regulated in the nuclei of glands (P < 0.05) and surface (luminal) epithelium (P < 0.01) by 60 days and maintained at 120 days. There was a significant reduction in stromal VEGF protein expression by day 120 of treatment (P < or = 0.01). CONCLUSION: The high incidence of amenorrhoea in women taking mifepristone may be related to changes in the regulation of vascular function.

Amenorrhea↗

PubMed2006

Intercellular adhesion molecule-1 expression in human endometrium: implications for long term progestin only contraception.

BACKGROUND: Neutrophils infiltrate the endometrium pre-menstrually and after long-term progestin only-contraceptive (LTPOC) treatment. Trafficking of neutrophils involves endothelial cell-expressed intercellular adhesion molecule (ICAM-1). Previous studies observed that ICAM-1 was immunolocalized to the endothelium of endometrial specimens across the menstrual cycle, but disagreed as to whether extra-endothelial cell types express ICAM-1 and whether ICAM-1 expression varies across the menstrual cycle. METHODS: Endometrial biopsies were obtained from women across the menstrual cycle and from those on LTPOC treatment (either Mirena or Norplant). The biopsies were formalin-fixed and paraffin-embedded with subsequent immunohistochemical staining for ICAM-1. RESULTS: The current study found prominent ICAM-1 staining in the endometrial endothelium that was of equivalent intensity in different blood vessel types irrespective of the steroidal or inflammatory endometrial milieu across the menstrual cycle and during LTPOC therapy. Unlike the endothelial cells, the glands were negative and the stromal cells were weakly positive for ICAM immunostaining. CONCLUSION: The results of the current study suggest that altered expression of ICAM-1 by endothelial cells does not account for the influx of neutrophils into the premenstrual and LTPOC-derived endometrium. Such neutrophil infiltration may depend on altered expression of neutrophil chemoattractants.

Adult↗

PubMed2006

11Beta-hydroxysteroid dehydrogenases in human endometrium.

Key reproductive events, such as menstruation and implantation, are considered to be inflammatory processes and glucocorticoids act as anti-inflammatory agents. The balance of expression of types 1 and 2 11beta-hydroxysteroid dehydrogenases (11betaHSD) controls the availability of cortisol to bind to the glucocorticoid receptor (GR) and mineralocorticoid receptor (MR). Expression profiles of glucocorticoid-metabolising enzymes and their cognate receptors have been characterized in the reproductive tract. We propose that factors that peripherally promote glucocorticoid action are part of an anti-inflammatory response to tissue remodelling in human endometrium. Protein and mRNA expression in endometrium were investigated using immunohistochemistry and quantitative real-time PCR. There was up-regulated expression of 11betaHSD-1 at menstruation and in first trimester decidua. 11BetaHSD-2 and GR were expressed across the cycle. The MR expression pattern across the cycle and in decidua implies progesterone may also play a regulatory role. The precise roles and interactions of these proteins require further investigation.

11-beta-Hydroxysteroid Dehydrogenase Type 1↗

PubMed2006

Gene expression profiling of mid to late secretory phase endometrial biopsies from women with menstrual complaint.

OBJECTIVE: The purpose of this study was to test whether a quantitative high-throughput molecular screen can be used to probe human endometrium and initiate the development of molecular diagnostic tools with potential for identification of therapeutic targets in women with menstrual complaints. STUDY DESIGN: Endometrium was collected from 10 patients with complaint of heavy bleeding, classified into mid or late secretory phase of the menstrual cycle by histologic dating and serum progesterone concentration. Total RNA was extracted and gene activity assessed using high-density oligonucleotide arrays. RESULTS: Statistical testing identified 83 'signature' genes whose expression levels differentiated the mid and late secretory phases of the menstrual cycle. CONCLUSION: The results show that the endometrium, a complex heterogeneous tissue, is amenable to high-throughput molecular analyses and this work provides further support for the future application of molecular profiling to clinical diagnosis.

Adult↗

PubMed2006

Regulation of human endometrial function: mechanisms relevant to uterine bleeding.

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.

Cell Hypoxia↗

PubMed2005

Prostacyclin receptor up-regulates the expression of angiogenic genes in human endometrium via cross talk with epidermal growth factor Receptor and the extracellular signaling receptor kinase 1/2 pathway.

Prostacyclin (PGI) is a member of the prostanoid family of lipid mediators that mediates its effects through a seven-transmembrane G protein-coupled receptor (IP receptor). Recent studies have ascertained a role for prostanoid-receptor signaling in angiogenesis. In this study we examined the temporal-spatial expression of the IP receptor within normal human endometrium and additionally explored the signaling pathways mediating the role of IP receptor in activation of target angiogenic genes. Quantitative RT-PCR analysis demonstrated the highest endometrial expression of the IP receptor during the menstrual phase compared with all other stages of the menstrual cycle. Immunohistochemical analysis localized the site of IP receptor expression to the glandular epithelial compartment with stromal and perivascular cell immunoreactivity. Expression of the immunoreactive IP receptor protein was greatest during the proliferative and early secretory phases of the menstrual cycle. To explore the role of the IP receptor in glandular epithelial cells, we used the Ishikawa endometrial epithelial cell line. Stimulation of Ishikawa cells and human endometrial biopsy explants with 100 nm iloprost (a PGI analog) rapidly activated ERK1/2 signaling and induced the expression of proangiogenic genes, basic fibroblast growth factor, angiopoietin-1, and angiopoietin-2, in an epidermal growth factor receptor (EGFR)-dependent manner. Furthermore, EGFR colocalized with IP receptor in the glandular epithelial compartment. These data suggest that PGI-IP interaction within glandular epithelial cells can promote the expression of proangiogenic genes in human endometrium via cross talk with the EGFR.

Angiopoietin-1↗

PubMed2005

Hypoxia-inducible factor-1alpha expression in human endometrium and its regulation by prostaglandin E-series prostanoid receptor 2 (EP2).

The menstrual cycle is a complex interaction of sex steroids, prostanoids, and cytokines that lead to coordinated tissue degradation, regeneration and repair. The transcription factor hypoxia-inducible factor (HIF-1) plays critical roles in cellular responses to hypoxia, the generation of an inflammatory response and vasculogenesis through transcriptional activation of angiogenic genes. We hypothesize that HIF-1 is expressed in human endometrium and that locally synthesized prostaglandins (PGE2 and PGF(2alpha)) regulate HIF-1 activity. Here we demonstrate that PGE2 up-regulates HIF-1alpha mRNA and protein via the E-series prostanoid receptor 2 (EP2), and this up-regulation is dependent on epidermal growth factor receptor kinase activity. We show the tight temporal-spatial confinement of HIF-1alpha protein expression in endometrium across the cycle. HIF-1alpha is expressed exclusively during the secretory and menstrual phases. Protein expression is maximal at progesterone withdrawal during the late secretory and menstrual phase. HIF-1alpha protein colocalizes with prostaglandin EP2 receptor in glandular cells. In contrast, HIF-1beta/aryl receptor nuclear translocator 1 expression occurs throughout the cycle but is maximal in glandular cells during the proliferative phase. This provides evidence for a role for HIF-1 in the menstrual cycle and demonstrates that HIF-1 activation in human endometrium may occur via a PGE2-regulated pathway and provides a coordinated pathway from progesterone withdrawal through to angiogenic gene expression via HIF-1.

Endometrium↗

PubMed2005

Progestogen only contraception and endometrial break through bleeding.

Progestogen only contraceptives (POC) provide a safe and effective method of fertility regulation. Unfortunately, they are commonly associated with the problem of endometrial break through bleeding (BTB), often leading to discontinuation of use. An increase in endometrial vascular fragility has been demonstrated as an important mechanism that contributes to BTB but our understanding of the interaction between exogenous steroid use and endometrial vasculature remains incomplete. This review sets out to describe a number of commonly used POC, their effects on endometrial morphology and possible molecular and cellular mechanisms that may lead to unscheduled bleeding.

Angiogenesis Inducing Agents↗

PubMed2005

Endocrine regulation of menstruation.

In 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. Tissue repair, growth, angiogenesis, differentiation, and receptivity ensue to prepare the endometrium for implantation in the next cycle. Ovarian sex steroids through interaction with different cognate nuclear receptors regulate the expression of a cascade of local factors within the endometrium that act in an autocrine/paracrine and even intracrine manner. Such interactions initiate complex events within the endometrium that are crucial for implantation and, in the absence thereof, normal menstruation. A clearer understanding of regulation of normal endometrial function will provide an insight into causes of menstrual dysfunction such as menorrhagia (heavy menstrual bleeding) and dysmenorrhea (painful periods). The molecular pathways that precipitate these pathologies remain largely undefined. Future research efforts to provide greater insight into these pathways will lead to the development of novel drugs that would target identified aberrations in expression and/or of local uterine factors that are crucial for normal endometrial function.

Adolescent↗

PubMed2005

Chemokine expression is dysregulated in the endometrium of women using progestin-only contraceptives and correlates to elevated recruitment of distinct leukocyte populations.

BACKGROUND: Breakthrough bleeding (BTB) is the most common reason for discontinuation of progestin-only (p-only) contraceptives, yet the causes are unknown. Use of p-only contraceptives is associated with elevated influx of endometrial leukocytes, similar to that observed perimenstrually or within decidualized endometrium. We hypothesized that chemokine expression is altered in women using p-only contraceptives, leading to abnormal leukocyte recruitment and BTB. METHODS: Expression of eight highly abundant endometrial chemokines was examined using immunohistochemistry and real-time PCR, in endometria from women using subdermal and intrauterine levonorgestrel and correlated to leukocyte subpopulations. RESULTS: Macrophage-derived chemokine (MDC), hemofiltrate CC chemokine-1 (HCC-1), monocyte chemoattractant protein-3 (MCP-3), interleukin-8 (IL-8) and eotaxin were strongly produced by epithelial glands, comparable to levels in premenstrual phase endometrium. Stromal cells were negative for chemokines in atrophic/shedding endometria, but intensely positive in highly decidualized tissues for MDC, MCP-3, HCC-1 and 6Ckine. Macrophage inflammatory protein-1beta (MIP-1b) and HCC-4 were suppressed in all p-exposed endometria. CONCLUSIONS: These data demonstrate that chemokine expression is dysregulated in p-exposed endometria, consistent with the morphological appearance of the endometrium and the leukocyte subsets present. This reinforces a potential role for chemokines in the elevated leukocyte recruitment that contributes to endometrial fragility and BTB.

Cell Proliferation↗

PubMed2005

Leukocyte populations and steroid receptor expression in human first-trimester decidua; regulation by antiprogestin and prostaglandin E analog.

CONTEXT: 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. OBJECTIVE: The aim of this study was to identify the separate and combined effects of the antiprogestin Mifepristone (single dose, 200 mg) and the prostaglandin E (PGE) analog (gemeprost) on leukocyte populations and steroid receptor expression in human first-trimester decidua. PATIENTS: Eighty women were recruited from the termination of pregnancy service with a gestational age of between 35 and 65 d at the time of surgical termination of pregnancy. MAIN OUTCOME MEASURES: Immunohistochemistry was used to measure macrophage (CD68 +ve), neutrophil (neutrophil elastase +ve), and uterine natural killer cell (CD56 +ve) populations and progesterone (PR(A) and PR(B)), estrogen (ERalpha and ERbeta), and androgen receptor (AR) expression. RESULTS: After administration of both antiprogestin and the PGE analog, macrophage and neutrophil numbers were significantly increased, whereas natural killer cell numbers were unchanged. Antiprogestin and PGE analog coadministration also significantly decreased PR and ERalpha immunoreactivity but had no effect on androgen receptor or ERbeta receptor expression. PGE analog alone was also capable of reducing PR expression. CONCLUSIONS: In this study, we demonstrate that the inflammatory response induced by antiprogestin in combination with PGE analog is accompanied by both increases in macrophages and neutrophils numbers and decreases in PR and ERalpha expression in human first-trimester decidua.

Abortifacient Agents↗

PubMed2005

Impact of cancer treatment on uterine function.

Fertility and future pregnancy potential are of concern to survivors of childhood cancer. Radiotherapy causes both ovarian and uterine damage. There are no reports of uterine damage after chemotherapy. The magnitude of risk is related to age at treatment, dose, and schedule. The dose of radiation required to destroy fifty percent of immature oocytes is <2 Gy. Reduced ovarian volume and low inhibin B and anti-Mullerian hormone concentrations in survivors with regular menses may be markers of incipient ovarian failure. Uterine damage, manifest by impaired growth and blood flow, is a likely consequence of pelvic irradiation. Uterine volume correlates with age at irradiation. Exposure of the pelvis to radiation is associated with an increased risk of miscarriage, midtrimester pregnancy loss, preterm birth, and low birthweight. The optimal dose and delivery route of estrogen replacement required to facilitate uterine growth in adolescent women treated with total body irradiation in childhood needs to be established. If female survivors of childhood cancer do achieve a pregnancy, then these pregnancies are high risk, pose a challenge for optimal mode of delivery, and require a multidisciplinary approach to management.

Adolescent↗

PubMed2005

The acceptability of home medical abortion to women in UK settings.

OBJECTIVE: To assess the acceptability of home medical abortion to women in UK settings. DESIGN: Questionnaire survey. SETTING: Four NHS gynaecology units in England and Scotland. SUBJECTS: Women undergoing conventional, hospital-based, medical abortion up to nine weeks of gestation. METHODS: A self-complete questionnaire explored the acceptability of abortion in hospital (including pain and bleeding experienced) and at home. Comparisons were made between centres (English and Scottish). MAIN OUTCOME MEASURE: Women's views on home administration of misoprostol for medical abortion; perceived acceptability and perceived ability to cope with the process at home. RESULTS: Sixty-six percent (366/553) of the questionnaires were returned: Edinburgh, 204 (56%); London, 92 (25%); Hull, 43 (12%); and Glasgow, 27 (7%). Individual questionnaire items were answered by varying numbers of women: 228/320 (71%; 95% CI: 66-76%) said there was nothing that happened during abortion in the hospital that they would have been unable to cope with at home; 123/342 (36%; 95% CI: 31-41%) said they would have opted to have home abortion, had that choice been available. However, 219/342 (64%; 95% CI: 59-69%) indicated that they would prefer to have abortion in the hospital. The majority of women said they would have coped at home with bleeding (280/355, 79%; 95% CI: 74-83%) and with pain if given analgesia (203/268, 76%; 95% CI: 70-81%). CONCLUSION: This study suggests that most women would welcome being offered the choice of having medical abortion at home or in hospital. The development of home abortion must be seen as complementary, not an alternative, to hospital services.

Abortifacient Agents, Nonsteroidal↗

PubMed2004

Endometrial endothelial cell steroid receptor expression and steroid effects on gene expression.

Controversy exists regarding the expression of specific steroid receptor proteins and mRNA in human microvascular endometrial endothelial cells (HEECs). Thus, we studied steroid receptor expression in early passaged HEEC cultures and freshly isolated HEECs. Analysis of estrogen receptor (ER) and progesterone receptor (PR) mRNA levels was carried out with real-time quantitative RT-PCR, and the repertoire of genes activated by their respective steroid ligands was assessed by mRNA microarray analyses of 18,400 genes and expressed sequence tags. We observed that cultured and freshly isolated HEECs each express ER-beta mRNA but not ER-alpha. In addition, PR mRNA was also detectable in both HEEC sources. Microarray analysis demonstrated that treatment of HEEC cultures with either estradiol or medroxyprogesterone acetate produced differential effects on a wide variety of genes, and cluster analysis demonstrated that many of the genes are involved in intracellular signaling and enzymatic pathways. Thus, quantitative RT-PCR and microarray analyses demonstrate that HEECs express ER-beta and PR mRNA and that gene expression by HEECs is differentially regulated by treatment with estrogen or progestin.

Cells, Cultured↗

PubMed2004

Menorrhagia I: measured blood loss, clinical features, and outcome in women with heavy periods: a survey with follow-up data.

OBJECTIVE: Menorrhagia is defined as blood loss of >80 mL, but in routine clinical practice measurement is seldom undertaken. Our aim was to identify the features of the clinical history that best predict menorrhagic blood loss. STUDY DESIGN: A questionnaire survey of 952 menstrual complaint referrals at 3 hospital gynecology clinics in Glasgow and Edinburgh included 226 women with putatively heavy periods who also had consented to the measurement of their blood loss. RESULTS: Only 34% (95% CI, 28%-40%) of women had blood loss volume of >80 mL, but the volume was associated with subjective heaviness of period. Logistic regression with ferritin status, clots, and changing rate during full flow correctly predicts a loss of >80 mL for 76% of women (n=161 patients; sensitivity, 60%; specificity, 86%). Diagnosis and treatment of patients seem unrelated to the volume of blood loss. CONCLUSION: The subjective judgment of the volume of blood loss is better than has been believed. Clinical features can be combined to predict losses of >80 mL.

Adult↗

PubMed2004

Menorrhagia II: is the 80-mL blood loss criterion useful in management of complaint of menorrhagia?

OBJECTIVE: Menorrhagia is defined in terms of statistical"abnormality"as blood loss of >80 mL. We examined the usefulness of this definition in women who were referred to gynecology clinics with heavy periods. STUDY DESIGN: A questionnaire survey of 952 menstrual complaint referrals at 3 hospital gynaecology clinics in Glasgow and Edinburgh included 226 women with heavy periods who had also consented to the measurement of their blood loss. RESULTS: Women reported a range of problems with their periods, but absolute volume (31.2%) was less prevalent than period pain (37.5%), mood change (35.7%), and change in the amount (volume) of the period (33.8%). Although there were associations with volume, these associations were due to the heaviest and lightest of the loss groups, whereas the 2 groups with loss either side of 80 mL were virtually indistinguishable. CONCLUSION: The 80-mL criterion for menorrhagia is of limited clinical usefulness because it is prognostic neither for problems nor iron status and apparently does not guide management.

Adult↗

PubMed2004

Coexpression of fractalkine and its receptor in normal human endometrium and in endometrium from users of progestin-only contraception supports a role for fractalkine in leukocyte recruitment and endometrial remodeling.

Leukocytes are critical mediators of endometrial remodeling, but the mechanisms by which leukocyte subpopulations enter the uterus are currently unknown. Endometrial leukocytes have no genomic progesterone receptors; thus, we hypothesized that leukocyte migration is induced indirectly by progesterone-regulated chemokines. Fractalkine (CX3CL1), a chemotactic membrane-bound adhesion factor, and its receptor (CX3CR1) were assessed by immunohistochemistry in endometrial samples across the menstrual cycle, in early pregnancy, and in women using progestin-only contraceptives. Fractalkine was localized predominantly to glandular epithelial and decidualized stromal cells, with the highest staining intensity in the secretory phase and early pregnancy. It was also detected in subpopulations of endometrial leukocytes (macrophages and uterine NK cells), with maximal numbers during the proliferative phase and early pregnancy. CX3CR1 was similarly colocalized to the glandular epithelium and decidualized stromal cells, with the highest expression in the secretory phase. CX3CR1-positive leukocytes (macrophages and neutrophils) were in greatest abundance during the menstrual phase. In the endometrium of women using progestin-only contraceptives, immunoreactive fractalkine was markedly reduced in the glandular epithelium, but was increased in decidualized stroma and infiltrating leukocytes. These findings support a number of roles for fractalkine in the endometrium, in the secretory phase, in early pregnancy, and when influenced by progestin-only contraceptives.

CX3C Chemokine Receptor 1↗

PubMed2004

Low-dose mifepristone inhibits endometrial proliferation and up-regulates androgen receptor.

Mifepristone in daily low doses has contraceptive potential by inhibiting ovulation. Follicular development is maintained, and although the endometrium is exposed to unopposed estrogen, there are no signs of hyperplasia or atypia. The mechanism of this antiestrogenic action is unknown. We have investigated the effect of daily low-dose mifepristone on proliferation markers and steroid receptors in surface epithelium, glands, and stroma of the endometrium. Endometrial biopsies were collected from 16 women before (late proliferative) and 60 and 120 d after taking 2 or 5 mg mifepristone daily for 120 d. Endometrial proliferation (H3 mitosis marker) and steroid (estrogen, progesterone, and androgen) receptor content were studied using standard immunocyotchemistry techniques. There was a significant decrease in the expression of H3 mitosis marker (P <or= 0.001) and progesterone receptor (P < 0.05) in endometrial glands and stroma by d 60 of treatment. In contrast, the expression of androgen receptor increased (P < 0.01) in glands, surface epithelium, and stroma compared with the pretreatment sample. These changes were maintained at 120 d of treatment. The expression of estrogen receptor was unchanged in stroma and surface epithelium; however, there was a significant decrease in expression after 120 d of treatment (P = 0.034). As androgens can antagonize estrogen action, enhanced glandular androgen receptor expression induced by mifepristone could play a role in its antiproliferative effects.

Adult↗