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Terzidou V, Lee YS, Thornton S, Sullivan M, Bennett PR. Identification of the response region on the oxytocin receptor (OTR) promoter which is important for the synergistic transactivation of OTR by C/EBPβ and NF-κB transcription factors. J OBSTET GYNAECOL 2003. [DOI: 10.1080/718591691] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Loudon JAZ, Sooranna SR, Bennett PR, Johnson MR. Changes in progesterone receptor isoforms in cultured human uterine smooth muscle cells with pregnancy, mechanical stretch and labour at term. J OBSTET GYNAECOL 2003. [DOI: 10.1080/718591773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Sullivan MHF, Alvi SA, Brown NL, Elder MG, Bennett PR. The effects of a cytokine suppressive anti-inflammatory drug on the output of prostaglandin E(2) and interleukin-1 beta from human fetal membranes. Mol Hum Reprod 2002; 8:281-5. [PMID: 11870236 DOI: 10.1093/molehr/8.3.281] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Fetal membranes are a primary source of prostaglandins and pro-inflammatory cytokines implicated in human parturition, so the inhibition of inflammatory pathways may be of benefit in pregnancies complicated by premature labour. We have therefore investigated the effects of a cytokine-suppressant anti-inflammatory drug (CSAID) on the output of prostaglandin E(2) (PGE(2)) and interleukin (IL)-1 beta from human fetal membranes in vitro. Bacterial endotoxin increased the expression of mRNA for IL-1 beta and type-2 cyclo-oxygenase (COX-2), and there were corresponding increases in the output of IL-1 beta protein and PGE(2). The CSAID decreased IL-1 beta protein, COX-2 expression and PGE(2) output, but not mRNA for IL-1 beta, indicating a post-translational effect on the production of IL-1 beta and a transcriptional affect on COX-2, with an overall reduction in PGE(2). These findings are consistent with the effects of CSAIDs in other systems, and indicate that they are of possible use in premature labour.
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Campagnoli C, Roberts IA, Kumar S, Bennett PR, Bellantuono I, Fisk NM. Identification of mesenchymal stem/progenitor cells in human first-trimester fetal blood, liver, and bone marrow. Blood 2001; 98:2396-402. [PMID: 11588036 DOI: 10.1182/blood.v98.8.2396] [Citation(s) in RCA: 900] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Human mesenchymal stem/progenitor cells (MSCs) have been identified in adult bone marrow, but little is known about their presence during fetal life. MSCs were isolated and characterized in first-trimester fetal blood, liver, and bone marrow. When 10(6) fetal blood nucleated cells (median gestational age, 10(+2) weeks [10 weeks, 2 days]) were cultured in 10% fetal bovine serum, the mean number (+/- SEM) of adherent fibroblastlike colonies was 8.2 +/- 0.6/10(6) nucleated cells (69.6 +/- 10/microL fetal blood). Frequency declined with advancing gestation. Fetal blood MSCs could be expanded for at least 20 passages with a mean cumulative population doubling of 50.3 +/- 4.5. In their undifferentiated state, fetal blood MSCs were CD29(+), CD44(+), SH2(+), SH3(+), and SH4(+); produced prolyl-4-hydroxylase, alpha-smooth muscle actin, fibronectin, laminin, and vimentin; and were CD45(-), CD34(-), CD14(-), CD68(-), vWF(-), and HLA-DR(-). Fetal blood MSCs cultured in adipogenic, osteogenic, or chondrogenic media differentiated, respectively, into adipocytes, osteocytes, and chondrocytes. Fetal blood MSCs supported the proliferation and differentiation of cord blood CD34(+) cells in long-term culture. MSCs were also detected in first-trimester fetal liver (11.3 +/- 2.0/10(6) nucleated cells) and bone marrow (12.6 +/- 3.6/10(6) nucleated cells). Their morphology, growth kinetics, and immunophenotype were comparable to those of fetal blood-derived MSCs and similarly differentiated along adipogenic, osteogenic, and chondrogenic lineages, even after sorting and expansion of a single mesenchymal cell. MSCs similar to those derived from adult bone marrow, fetal liver, and fetal bone marrow circulate in first-trimester human blood and may provide novel targets for in utero cellular and gene therapy.
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Elliott CL, Loudon JA, Brown N, Slater DM, Bennett PR, Sullivan MH. IL-1beta and IL-8 in human fetal membranes: changes with gestational age, labor, and culture conditions. Am J Reprod Immunol 2001; 46:260-7. [PMID: 11642674 DOI: 10.1034/j.1600-0897.2001.d01-11.x] [Citation(s) in RCA: 84] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
PROBLEM Interleukin (IL)-1beta and IL-8 are associated with labor. This study aimed to characterize their concentrations in fetal membranes and any changes in these with advancing gestation and to define as to whether there are interactions between the membranes in their expression. METHOD OF STUDY mRNA and protein content of amnion and choriodecidua at increasing gestations and before and after labor at term were quantified. Membranes were also collected before and after labor, separated, and cultured. Protein production was measured by ELISA. RESULTS IL-1beta and IL-8 concentration increased in third trimester amnion and choriodecidua. Further increased expression of mRNA of both cytokines was found after labor in both membranes except IL-8 production by amnion. Choriodecidua produced more of each cytokine than amnion, however, no interaction between the membranes was demonstrated by culture. CONCLUSIONS Increasing expression of IL-1beta and IL-8 in amnion and choriodecidua in the third trimester and after labor supports a role for these cytokines in the establishment of labor.
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Pieber D, Allport VC, Bennett PR. Progesterone receptor isoform A inhibits isoform B-mediated transactivation in human amnion. Eur J Pharmacol 2001; 427:7-11. [PMID: 11553358 DOI: 10.1016/s0014-2999(01)01189-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Human amnion cells were transfected with progesterone receptor A and/or B, and the progesterone-dependent reporter construct, mouse mammary tumor virus promoter (MMTV), linked to a luciferase gene. In progesterone receptor B-expressing amnion that had been cultured before the onset of labour, treatment with progesterone resulted in an eightfold increase of the reporter activity, whereas in laboured cells, no such increase was seen. In contrast, progesterone receptor A was a weak activator of transcription in laboured and non-laboured amniocytes. When the isoforms A and B of the progesterone receptor were co-transfected, progesterone receptor A exhibited a marked inhibitory effect on progesterone receptor B-mediated transcription. These results show that progesterone receptors A and B function differentially, and progesterone receptor A is a transdominant repressor of progesterone receptor B-mediated transcription in human term amnion.
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Pieber D, Allport VC, Hills F, Johnson M, Bennett PR. Interactions between progesterone receptor isoforms in myometrial cells in human labour. Mol Hum Reprod 2001; 7:875-9. [PMID: 11517295 DOI: 10.1093/molehr/7.9.875] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Progesterone acts to maintain uterine quiescence during pregnancy. In contrast to many other species, no decrease in maternal serum levels of progesterone can be observed in humans before the onset of labour. Therefore, a 'functional' progesterone withdrawal in association with labour has been proposed. In humans the progesterone receptor (PR) exists in two isoforms, PR-A and PR-B. While PR-B generally mediates the effects of progesterone upon gene transcription, the role of PR-A during pregnancy, and in parturition, is unknown. In this study, term myometrium cells cultured before the onset of labour were transiently transfected with expression vectors for either PR-A or PR-B. Only those cells expressing PR-B significantly increased expression of a progesterone-sensitive reporter when stimulated with progesterone. Co-transfection of both isoforms of PR demonstrated that PR-A is a dominant repressor of transactivation in these cells. Western blot analysis showed that PR-A is present in human myometrium samples taken only after, but not before, the onset of labour. These data suggest that increased expression of PR-A in human myometrium may contribute to 'functional' progesterone withdrawal and the initiation of human labour.
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Elliott CL, Allport VC, Loudon JA, Wu GD, Bennett PR. Nuclear factor-kappa B is essential for up-regulation of interleukin-8 expression in human amnion and cervical epithelial cells. Mol Hum Reprod 2001; 7:787-90. [PMID: 11470867 DOI: 10.1093/molehr/7.8.787] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Interleukin-8 (IL-8) is a cytokine which recruits and activates neutrophils into tissue stroma. It is present in uterine tissues and its concentration increases in the third trimester and with labour. The promoter region of the IL-8 gene contains binding sites for the transcription factors, nuclear factor-kappa B (NF-kappaB), activator protein-1 (AP-1) and CCAAT/enhancer-binding protein (C/EBP). These are in close proximity to each other and to the coding region of the gene. This study used site-directed mutagenesis of each of these sites to examine the relative importance of each site in IL-8 gene expression in a cervical cell line and in amnion cells obtained before and after labour. We found that the NF-kappaB site was essential for basal and IL-1beta-stimulated gene expression in all cell types. Neither of the other binding sites was consistently essential for gene expression but may have an additive role in promoter activity. We conclude that the NF-kappaB binding site is essential for up-regulation of IL-8 gene expression in these uterine cell types. An increase in IL-8 expression has been shown to occur in the uterus in association with parturition and NF-kappaB binding to the promoter may be of importance at this time.
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Choolani M, O'Donnell H, Campagnoli C, Kumar S, Roberts I, Bennett PR, Fisk NM. Simultaneous fetal cell identification and diagnosis by epsilon-globin chain immunophenotyping and chromosomal fluorescence in situ hybridization. Blood 2001; 98:554-7. [PMID: 11468149 DOI: 10.1182/blood.v98.3.554] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Isolating fetal erythroblasts from maternal blood offers a promising noninvasive alternative for prenatal diagnosis. The current immunoenzymatic methods of identifying fetal cells from background maternal cells postenrichment by labeling gamma-globin are problematic. They are nonspecific because maternal cells may produce gamma-globin, give poor hybridization efficiencies with chromosomal fluorescence in situ hybridization (FISH), and do not permit simultaneous visualization of the fetal cell identifier and the FISH signal. We describe a novel technique that allows simultaneous visualization of fetal erythroblast morphology, chromosomal FISH, and epsilon-globin labeled with AMCA (7-amino-4-methylcoumarin-3-acetic acid). AMCA was chosen as the fluorescent label to circumvent the problem of heme autofluorescence because the mean difference in relative fluorescence intensity between fetal erythroblasts stained positive for antiglobin antibody and autofluorescence of unstained cells was greater with AMCA (mean 43.2; 95% confidence interval [CI], 34.6-51.9; SD = 14.0) as the reporting label compared with fluorescein isothiocyanate (mean 24.2; 95% CI, 16.4-31.9; SD = 12.4) or phycoerythrin (mean 9.8; 95% CI, 4.8-14.8; SD = 8.0). Median FISH hybridization efficiency was 97%, comparable to the 98% (n = 5 paired samples) using Carnoy fixative. One epsilon-positive fetal erythroblast was identified among 10(5) maternal nucleated cells in 6 paired mixture experiments of fetal erythroblasts in maternal blood (P <.001). Male epsilon-positive fetal erythroblasts were clearly distinguishable from adult female epsilon-negative erythroblasts, with no false positives (n = 1000). The frequency of fetal erythroblasts expressing epsilon-globin declines linearly from 7 to 14 weeks' gestation (y = -15.8 x + 230.8; R(2) = 0.8; P <.001). We describe a rapid and accurate method to detect simultaneously fetal erythroblast morphology, intracytoplasmic epsilon-globin, and nuclear FISH. (Blood. 2001;98:554-557)
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Allport VC, Pieber D, Slater DM, Newton R, White JO, Bennett PR. Human labour is associated with nuclear factor-kappaB activity which mediates cyclo-oxygenase-2 expression and is involved with the 'functional progesterone withdrawal'. Mol Hum Reprod 2001; 7:581-6. [PMID: 11385114 DOI: 10.1093/molehr/7.6.581] [Citation(s) in RCA: 243] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human labour is associated with the up-regulation of prostaglandins within the uterus, synthesized via the type-2 cyclo-oxygenase enzyme (COX-2). These lead to remodelling of the fetal membranes and cervix and to stimulation of myometrial contractions. In the human, the principal source of prostaglandins is the amnion. Progesterone acts to promote myometrial quiescence, and in many species the onset of labour is preceded by withdrawal of progesterone. Humans show no systemic progesterone withdrawal, although biochemical changes within the uterus are similar to those in other species. A mutual negative interaction between the transcription factor nuclear factor (NF)-kappaB and the progesterone receptor (PR) has been reported. Using transient transfections and assays for transcriptional activation and promoter binding, we have shown that there is constitutive activity of NF-kappaB in amnion cells at the time of labour, and that COX-2 expression depends upon NF-kappaB. In cells obtained before labour, in which NF-kappaB activity is low, increasing the concentration of PR represses NF-kappaB dependent transcription, while stimulation with IL-1beta both increases NF-kappaB activity and represses PR activity. Our data suggest that human labour is associated with constitutive NF-kappaB activity within the amnion, which functions to increase the expression of COX-2 and appears to contribute to the 'functional progesterone withdrawal'.
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Welsh AW, Bennett PR, Fisk NM. Quantitative digital analysis of regional placental perfusion using power Doppler in placental abruption. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2001; 17:203-208. [PMID: 11309168 DOI: 10.1046/j.1469-0705.2001.00376.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
PURPOSE To apply digital imaging techniques to the quantification of placental vascularity using power Doppler. MATERIALS AND METHODS Regional placental blood flow was measured in a case of large placental abruption, shortly after presentation and 1 week later. Images were stored digitally and analysed using purpose-designed software (CQ Analysis) to extract and measure vascular energy information. The integrated color energy (ICE) was determined in the main body of placental tissue and in a cotyledon isolated by the retroplacental clot. RESULTS Initial assessment at 25 weeks showed only a small difference in integrated energy between normal placenta and the isolated cotyledon (ICE ratio 1.44, P < 0.04). One week later, perfusion in the isolated cotyledon had fallen both on qualitative and quantitative assessment (ICE ratio 3.98, P < 0.0001). This area subsequently became devascularized. CONCLUSION Placental perfusion may be quantified using digital power Doppler analysis. Further studies are indicated to evaluate its role in assessing regional and/or global placental perfusion as well as fetal organ perfusion.
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Groom KM, Bennett PR, Shennan AH. Randomised, double-blind, placebo controlled pilot study assessing nitroglycerin as a tocolytic. BJOG 2000; 107:1182-3. [PMID: 11002973 DOI: 10.1111/j.1471-0528.2000.tb11132.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Allport VC, Slater DM, Newton R, Bennett PR. NF-kappaB and AP-1 are required for cyclo-oxygenase 2 gene expression in amnion epithelial cell line (WISH). Mol Hum Reprod 2000; 6:561-5. [PMID: 10825375 DOI: 10.1093/molehr/6.6.561] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Prostaglandins are known to play an important role in human labour and are used clinically to induce labour onset. Cytokines, e.g. interleukin 1 beta (IL-1beta), are up-regulated in the amniotic fluid late in gestation and can increase prostaglandin production through the expression of cyclo-oxygenase 2 (COX-2), the prostaglandin synthetic isoform involved in human labour. We demonstrate in immortalized amnion epithelial (WISH) cells, that IL-1beta causes increased transcription of the COX-2 gene. Luciferase reporter constructs with site-directed mutagenesis of the two NF-kappaB sites and an AP-1 site in the COX-2 promoter showed reduced expression of luciferase in transient transfection studies. This suggests that the binding of transcription factors to these sites is essential for the regulation of COX-2 transcription in IL-1beta-treated WISH cells.
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Elliott CL, Slater DM, Dennes W, Poston L, Bennett PR. Interleukin 8 expression in human myometrium: changes in relation to labor onset and with gestational age. Am J Reprod Immunol 2000; 43:272-7. [PMID: 10872606 DOI: 10.1111/j.8755-8920.2000.430505.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PROBLEM Preterm labor remains the major cause of perinatal mortality and morbidity in normally formed babies. The mechanisms involved in the onset of preterm labor are poorly understood, mainly because the mechanisms initiating term labor remain ill-defined. METHOD OF STUDY Human myometrial samples were collected at cesarean delivery from preterm (26-36 weeks gestation) and term (37-41 weeks) women. Women at term were either non-laboring or laboring. The expressions of interleukin-8 (IL-8) mRNA and protein were measured by reverse transcriptase-polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. RESULTS The expression of both IL-8 mRNA and protein significantly increased in the term laboring group, compared with either the term non-laboring or preterm groups. Levels of IL-8 expression did not alter with advancing gestational age. CONCLUSIONS The increased expression of IL-8 in laboring myometria at term supports the hypothesis that up-regulation of IL-8 has a role in the initiation of labor in association with an influx of neutrophils and the release of their collagenolytic enzymes into uterine tissues.
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Houfflin-Debarge V, O'Donnell H, Overton T, Bennett PR, Fisk NM. High sensitivity of fetal DNA in plasma compared to serum and nucleated cells using unnested PCR in maternal blood. Fetal Diagn Ther 2000; 15:102-7. [PMID: 10720875 DOI: 10.1159/000020985] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
DNA analysis of blood is conventionally performed on cells - plasma and serum are discarded. Free DNA has been demonstrated in serum in cancer and autoimmune disorders and in pregnancy. We investigated possible noninvasive prenatal diagnosis using fetal DNA from maternal plasma and serum in pregnancy. Fetal gender was determined by PCR on DNA from maternal venous blood, serum and plasma of 65 women by boiling with or without phenol/chloroform extraction. When sensitivities were compared for plasma, additional phenol/chloroform extraction proved more sensitive than boiling alone (89 vs. 50%), the observed difference was 50% (CI 19 to 81%). Extracted plasma amplified better than extracted serum (89 vs. 46%), the observed difference being 44% (CI 22 to 66%). In contrast, fetal gender could not reliably be determined from DNA extracted from maternal nucleated blood cells. The size of plasma and serum DNA at 15-17 weeks of gestation was >1,500 bp. This work confirms the presence of fetal DNA in maternal plasma and serum which may be applicable to noninvasive prenatal diagnosis of paternally derived DNA sequences. We conclude that optimal sensitivity requires two methods of DNA extraction and that the use of plasma is preferred to that of serum.
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Sawdy RJ, Slater DM, Dennes WJ, Sullivan MH, Bennett PR. The roles of the cyclo-oxygenases types one and two in prostaglandin synthesis in human fetal membranes at term. Placenta 2000; 21:54-7. [PMID: 10692251 DOI: 10.1053/plac.1999.0438] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
UNLABELLED The aim of this study was to determine the relative contributions of cyclo-oxygenase (COX) types 1 and 2 to prostaglandin synthesis at term. METHODS Fetal membranes were collected from 6 pregnancies after elective caesarean section at term, prior to labour. The presence of COX-1 and COX-2 protein was determined using Western analysis. The relative contributions of the two isoforms of COX to prostaglandin synthesis were determined by incubation of fetal membrane discs with either a COX-2 selective inhibitor, SC236, or a COX-1 selective inhibitor, SC560, and measurement of prostaglandin release during 24 h using enzyme-linked immuno-sorbent assay (ELISA). RESULTS Both COX-1 and COX-2 protein were demonstrated in amnion and chorion-decidua. The COX-2 selective inhibitor, SC-236, significantly reduced prostaglandin synthesis, both in its COX-2 specific and higher, non-specific concentration ranges. The COX-1 selective inhibitor, SC-560, had no effect upon prostaglandin synthesis in its COX-1 specific concentration range, but did significantly reduce prostaglandin synthesis at higher, non-selective concentrations. CONCLUSIONS Fetal membranes contain both COX-1 and COX-2 at term, but only COX-2 contributes towards prostaglandin synthesis. COX-2 selective NSAI drugs will be as effective as non-selective agents in inhibition of fetal membrane prostaglandin synthesis and may represent a new strategy for tocolysis.
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Brown NL, Alvi SA, Elder MG, Bennett PR, Sullivan MH. The regulation of prostaglandin output from term intact fetal membranes by anti-inflammatory cytokines. Immunology 2000; 99:124-33. [PMID: 10651950 PMCID: PMC2327135 DOI: 10.1046/j.1365-2567.2000.00942.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Prostaglandins are some of the main mediators which control parturition, and their production by intrauterine tissues can be up-regulated by pro-inflammatory cytokines. Anti-inflammatory cytokines may oppose these effects, and in this study we have investigated how two such cytokines affected fetal membrane function. Interleukin-10 (IL-10) inhibited the output of prostaglandin E2 (PGE2) from intact fetal membranes under basal and lipopolysaccharide (LPS)-stimulated conditions, and there was a parallel decrease in the expression of mRNA for COX-2. IL-10 also inhibited the production of interleukin-1beta (IL-1beta) and the expression of mRNA for IL-1beta, indicating that this cytokine has a broad anti-inflammatory effect. Transforming growth factor-beta1 (TGF-beta1), which is generally considered to be anti-inflammatory had opposite effects on PGE2 production, in that it increased the output of PGE2 for up to 8 hr. TGF-beta1 increased levels of type-2 cyclo-oxygenase (COX-2) and cytosolic phospholipase A2 (cPLA2) protein, and also activated the cPLA2 enzyme present; the profile of effects is similar to that of the pro-inflammatory cytokine IL-1beta, and was not expected. Combinations of TGF-beta1 with IL-1beta also increased PGE2 output and caused appropriate changes in prostaglandin pathway enzymes, whereas TGF-beta1 and IL-1alpha had more limited effects. Further studies are needed to establish the physiological significance of these findings, but TGF-beta1 does not seem to act as an inhibitory cytokine in intact fetal membranes at term.
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Bartlett SR, Bennett PR, Campa JS, Dennes WJ, Slater DM, Mann GE, Poston L, Poston R. Expression of nitric oxide synthase isoforms in pregnant human myometrium. J Physiol 1999; 521 Pt 3:705-16. [PMID: 10601500 PMCID: PMC2269695 DOI: 10.1111/j.1469-7793.1999.00705.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
1. Endogenous nitric oxide has been proposed to play a role in the control of myometrial contractility in pregnancy. In this study, the expression, localisation and regulation of nitric oxide synthase (NOS) isoforms have been examined in human pregnant myometrium and cultured human myometrial smooth muscle cells, by immunoblotting, immunohistochemistry and reverse transcription-polymerase chain reaction. 2. Immunoblotting of extracts from freshly isolated myometrial tissue, affinity-enriched for NOS proteins by precipitation with ADP-sepharose, revealed expression of endothelial NOS (eNOS or NOS3) in tissues from preterm, term non-labour and active labour at term. Inducible NOS (iNOS or NOS2) and neuronal NOS (nNOS or NOS1) proteins were not detected at any stage of pregnancy. 3. Immunohistochemical detection showed that expression of eNOS protein was restricted to the endothelium of the myometrial vasculature, with no staining detected in myometrial smooth muscle cells. 4. Messenger RNA for all three NOS isoforms was detected, although iNOS and nNOS mRNAs were detectable only with high cycle number, implying a low copy number. 5. NOS isoforms were not detectable in human myometrial smooth muscle cells cultured from term non-labour pregnancies. Cytokine stimulation of cultured myometrial cells did not induce iNOS expression or nitrite accumulation in the culture medium, although both iNOS protein and nitrite release were detected in the human pulmonary epithelial cell line A549. 6. Levels of eNOS protein and of NOS mRNA expression were not correlated with gestational stage, suggesting that endogenously produced NO is not likely to be a modulator of myometrial tone during human pregnancy.
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Slater DM, Dennes WJ, Campa JS, Poston L, Bennett PR. Expression of cyclo-oxygenase types-1 and -2 in human myometrium throughout pregnancy. Mol Hum Reprod 1999; 5:880-4. [PMID: 10460228 DOI: 10.1093/molehr/5.9.880] [Citation(s) in RCA: 115] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Human labour is associated with increased prostaglandin synthesis within the uterus. The aim of this study was to examine the expression of the two isoforms of the central prostaglandin synthetic enzyme, cyclo-oxygenase (COX-1 and COX-2) in human myometrium throughout pregnancy and to test the hypothesis that COX in the myometrium may play a role in labour onset. Expression of COX-1 and COX-2 at the mRNA level was analysed using reverse transcriptase-polymerase chain reaction (RT-PCR) and at the protein level using Western blotting. No significant changes of COX-1 RNA or protein expression were observed either with gestational age or labour. COX-2 mRNA and protein expression increased at term with significant up-regulation occurring prior to the onset of labour (P < 0.005). These data would suggest that up-regulation of COX-2, rather than COX-1, mediates increased prostaglandin synthesis in human myometrium at term. The increased COX-2 expression observed preceded labour onset, suggesting that COX-2 has a role in labour onset, rather than its presence merely a consequence of labour.
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Brown NL, Slater DM, Alvi SA, Elder MG, Sullivan MH, Bennett PR. Expression of 5-lipoxygenase and 5-lipoxygenase-activating protein in human fetal membranes throughout pregnancy and at term. Mol Hum Reprod 1999; 5:668-74. [PMID: 10381823 DOI: 10.1093/molehr/5.7.668] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Lipoxygenase metabolites may be involved in human parturition. 5-lipoxygenase (5-LOX) catalyses the first steps in the synthesis of leukotrienes from arachidonic acid, and its activity is dependent on 5-LOX activating protein (FLAP). The expression of 5-LOX and FLAP were investigated in fetal membranes to determine whether there are changes with gestational age or at term with the onset of labour. No significant differences were found in the expression of 5-LOX or FLAP mRNA in the amnion at different gestational ages or at term. In the chorion-decidua, 5-LOX mRNA expression was significantly higher in the first trimester of pregnancy than in the second and third trimesters. At term, there was a significant increase in both 5-LOX mRNA and protein expression in the chorion-decidua in the time after labour, compared with the time before labour. The expression of FLAP mRNA was also significantly higher in the chorion-decidua in the first trimester of pregnancy compared with the third trimester, and at term in the time after labour compared with the time before labour. Expression of FLAP protein was not studied, as an antibody is not currently available. These results are consistent with a role for 5-LOX and FLAP in the control of parturition at term, and also suggest an involvement earlier in pregnancy.
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Alvi SA, Rajasingam D, Brown NL, Elder MG, Bennett PR, Sullivan MH. The production of interleukin-1beta from human fetal membranes is not obligatory for increased prostaglandin output. Immunology 1999; 97:249-56. [PMID: 10447739 PMCID: PMC2326835 DOI: 10.1046/j.1365-2567.1999.00769.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Bacterial endotoxin increased the expression of mRNA (maximal after 4 hr) for interleukin-1beta (IL-1beta) and the release of mature protein from intact human fetal membranes. In contrast, the change in expression of mRNA for type 2 cyclo-oxygenase (COX-2) was biphasic, with peaks after 0.5-1 hr and after 8 hr of culture. An antibody to IL-1beta was without effect after 4 hr of culture, inhibited endotoxin-stimulated prostaglandin E2 (PGE2) production after 8 hr of culture, and caused a parallel decrease in the expression of mRNA for COX-2. We conclude that endotoxin induced the expression of COX-2 through IL-1beta-independent and IL-1beta-dependent mechanisms, and these differences are time dependent. Corticotrophin-releasing hormone (CRH) or platelet-activating factor (PAF) also increased the expression of mRNA for IL-1beta and the release of IL-1beta from some, but not all, fetal membranes. The antibody to IL-1beta did not affect CRH-stimulated or PAF-stimulated PGE2 production or COX-2 expression. We conclude that CRH and PAF can induce the expression of IL-1beta, but this is not obligatory for increased PGE2 release, and the effect of these stimuli on COX-2 expression is a direct, IL-1beta-independent effect.
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Willix-Payne DJ, Sun MY, Elder MG, Bennett PR, Sullivan MH. An inhibitor of type-1 cyclo-oxygenase in tissues from human pregnancy. Acta Obstet Gynecol Scand 1999; 78:403-7. [PMID: 10326885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
BACKGROUND Previous work has shown that first trimester human decidua contains a protein which directly inhibits the activity of type-1 cyclo-oxygenase (COX-1). METHODS Activity assays for cyclo-oxygenase types I and II were developed. Cell cytosol was prepared from a number of different sources: human placenta and decidua (first and third trimester), two placental cell-lines (BeWo and TCL-1), an endometrial stromal cell-line and K562 erythroleukemia cells. The effects of all cytosols on activity of type I cyclo-oxygenase, and of cytosols from BeWo choriocarcinoma and decidual cells on type II enzyme, were tested. RESULTS Cytosols from first trimester human placenta, two placental cell-lines, an endometrial stromal cell-line and K562 erythroleukemia cells all inhibited the type I enzyme. The inhibitor protein could not be detected in third trimester human decidual cells after labor, and was present only at very low levels in third trimester decidua prior to the onset of labor. Cytosols from BeWo and decidual cells had no effect on the activity of the type-2 cyclo-oxygenase enzyme. CONCLUSIONS The inhibitor of type I cyclo-oxygenase was not specific to pregnancy-related tissues, and may be a general regulator of this enzyme. Lower levels of inhibitor were present at term, but the physiological significance of this is unclear. The cytosolic inhibitor appears to be specific to the type I enzyme.
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Alvi SA, Brown NL, Bennett PR, Elder MG, Sullivan MH. Corticotrophin-releasing hormone and platelet-activating factor induce transcription of the type-2 cyclo-oxygenase gene in human fetal membranes. Mol Hum Reprod 1999; 5:476-80. [PMID: 10338371 DOI: 10.1093/molehr/5.5.476] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Corticotrophin-releasing hormone (CRH) and platelet-activating factor (PAF) are considered to be involved in the physiological processes of human labour. Both may have dual effects, directly regulating myometrial contractility and fetal membrane prostaglandin production. During this study, we investigated the mechanisms through which CRH and PAF exert their latter effect. CRH and PAF increased prostaglandin production from intact fetal membrane discs, with a maximum stimulation after 8 h of culture. Reverse transcription-polymerase chain reaction (RT-PCR) analyses using primers specific for type-2 cyclo-oxygenase (COX-2) showed that CRH and PAF increased the transcription of COX-2 mRNA two-fold after 8 h culture. These data indicate that the increased fetal membrane prostaglandin production in response to CRH or PAF may involve the induction of COX-2.
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Abstract
Preterm labour and delivery pose an increasing problem to the obstetrician. Improvements in tocolysis with the recent introduction of new therapeutic targeting strategies, and a reappraisal of the safety and relative efficacy of some older compounds, have led to a tendency away from prescribing beta-sympathomimetic agents. Infection prophylaxis and promotion of fetal lung maturity are deemed advantageous, but treatment protocols have not been clarified. This review examines the important publications of the past year in these areas.
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