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PubMed1985

The influence of prostaglandin E2 and oxytocin on the incorporation of [3H]proline and [3H]glucosamine in the human amnion.

Fetal membranes were obtained in connection with 1st-trimester abortion and vaginal delivery or elective caesarean section at term. Pieces of the isolated amnion membrane were incubated in vitro with [3H]proline or [3H]glucosamine in the presence of prostaglandin (PG) E2 or oxytocin. PGE2 reduced the labelling with [3H]proline in the 1st trimester and in membranes obtained at vaginal delivery, whereas an increase of incorporation was observed before start of labour. Oxytocin reduced [3H]proline labelling at any stage. In membranes from vaginally delivered women both oxytocin and PGE2 stimulated the incorporation of [3H]glucosamine, whereas oxytocin diminished radiolabelling in the other experimental groups. Regarding the radiolabelling with [3H]proline and [3H]glucosamine as reflecting the de novo formation of collagen and proteoglycans, respectively, it is suggested that both PGE2 and oxytocin, by their influence on connective tissue metabolism, may regulate the tensile properties of the fetal membranes.

5,8,11,14-Eicosatetraynoic Acid↗
PubMed1983

Mechanism of interferon action: human leukocyte and immune interferons regulate the expression of different genes and induce different antiviral states in human amnion U cells.

The inhibition of virus replication and the induction of protein phosphorylation were examined in human amnion U and human fibroblast GM2767A cells treated with highly purified cloned human leukocyte and immune interferons synthesized in Escherichia coli. Both leukocyte interferon (IFN-alpha A) and immune interferon (IFN-gamma) possessed antiviral activity as measured by the single cycle yield reduction of vesicular stomatitis virus (VSV) in the human U and GM2767A cell lines. By contrast, only IFN-gamma and not IFN-alpha A inhibited the single cycle replication of reovirus in U and GM2767A cells. IFN-alpha A, but not IFN-gamma, efficiently induced the double-stranded RNA-dependent phosphorylation of the ribosome-associated protein P1 and the alpha subunit of protein synthesis initiation factor eIF-2 in U cells. However, neither IFN-alpha A nor IFN-gamma induced the phosphorylation of P1 and eIF-2 alpha in GM2767A cells. The antiviral activities of IFN-alpha A and IFN-gamma were synergistic for the inhibition of VSV but not for the inhibition of reovirus or the induction of protein phosphorylation. These results suggest that human leukocyte and immune interferons differentially regulate the expression of certain genes and induce mechanistically distinct antiviral states in human cells.

Amnion↗
PubMed1994

Interleukin-1 beta regulates the inducible cyclooxygenase in amnion-derived WISH cells.

The purpose of this study was to determine the mechanism of enhanced prostaglandin synthesis in amnion-derived WISH cell cultures when stimulated by interleukin-1 beta (IL-1 beta). Confluent monolayer cultures of WISH cells were incubated with human recombinant IL-1 beta (0.001-10 ng/ml) for 0-24 hours, while control cells received medium alone. PGE2 production was measured by specific radioimmunoassay. IL-1 beta enhanced the production of PGE2 in a dose- and time-dependent manner with enhanced production detectable by 2 h following exposure. Immunoblot analysis using isoform-specific antibodies showed that the inducible cyclooxygenase enzyme, i.e., COX-2, was expressed by 2 h in IL-1 treated cells, while the constitutive COX-1 remained unaltered in its expression. Northern blot analysis demonstrated that COX-2 mRNA expression was not detected in untreated cells, but became evident after a 30-min exposure to IL-1 beta (10 ng/ml). COX-1 mRNA was detected under basal conditions and did not increase significantly following IL-1 beta treatment. The close parallel between the kinetics of COX-2 mRNA and protein expression and PGE2 accumulation in the medium, as well as the constitutive, unregulated nature of the COX-1 isoform, indicates that cytokine-driven PGE2 formation in WISH cells may be mediated by de novo expression of the novel COX-2 enzyme.

Amnion↗
PubMed1994

Brief communication: sliding displacement of amnion and chorion following controlled laser wounding suggests a mechanism for short-term sealing of ruptured membranes.

The Erbium-YAG laser was used to produce narrow wounds of defined depth in term amniochorion. The charring effect of the laser meant that sites could be readily localized in histological sections. During brief post-wounding incubations, sliding displacement of the amnion relative to the chorion occurred through the plane of the spongy layer. This suggests a possible short-term mechanism whereby a spontaneous rupture could be sealed in vivo.

Amnion↗
PubMed1996

Stimulation of prostaglandin E2 synthesis by interleukin-1beta is amplified by interferons but inhibited by interleukin-4 in human amnion-derived WISH cells.

Human amnion-derived WISH cells synthesize little prostaglandin E2 at the basal state. However, the cells were stimulated greatly to synthesize prostaglandin E2 by interleukin-1beta in a dose-dependent manner. Stimulation by interleukin-1beta was synergistically increased by pretreatment of the cells with interferon alpha or gamma, which alone were inactive. Synergism by interferons was dose-dependent. Stimulation by interleukin-1beta, on the contrary, was inhibited by preincubation of the cells with interleukin-4. Inhibition by interleukin-4 was also dose-dependent. Regulation of prostaglandin E2 synthesis by cytokines was further examined at the m-RNA level of cyclooxygenase-2. Quantitative reverse transcription-polymerase chain reaction indicated that the m-RNA level was not increased by interferon-gamma but was synergistically increased by interferon-gamma plus interleukin-1beta. Furthermore, the m-RNA level increased by interleukin-1beta was attenuated by interleukin-4. These results indicate that regulation of interleukin-1beta-stimulated prostaglandin E2 synthesis by interferons and interleukin-4 is controlled at the m-RNA level of cyclooxygenase-2.

Amnion↗
PubMed1996

Involvement of methionine in the synthesis of certain membrane-associated nucleotide sugars by human amnion (WISH) cells.

A plasma membrane preparation from human amnion (WISH) cells contained uridine diphosphate sugars and methyl-uridine diphosphate (mUDP) sugars. The synthesis of mUDP-glucose, mUDP-mannose, and mUDP-fucose by the membrane preparation occurred when supplemented with uridine-5'-diphosphate-glucose and S-adenosyl-L-methionine. It is suggested that this newly recognized route for fucose biosynthesis might be employed by certain transformed cells, and may partly account for the methionine dependence of certain human tumors. Additionally, it is suggested that, in colon cancer, a deficiency of folic acid and methionine might affect mUDP-sugar biosynthesis rather than the methylation of DNA.

3T3 Cells↗
PubMedDate not supplied

Ethanol effect on the ionic transfer through isolated human amnion. I. Preventive and antagonistic actions of some nutrients and of their synthetic congeners.

The inhibition of the placental transfer of nutrients was studied in the pathogenesis of the fetal alcohol syndrome. Ethanol reduces the ionic transfer through the human amnion. In this study, the preventive and antagonistic actions of natural nutrients (Mg2+, Ca2+, taurine, homotaurine, gamma-aminobutyric acid) and of their synthetic congeners (Ca2+-taurinate, Ca2+-acetyltaurinate, Ca2+-acetylhomotaurinate) were observed on the amniotic conductance which was modified by ethanol. All the molecules, except Mg, demonstrated protective actions on the fetal side. The effect varied with the molecule and its concentration. An absolute protective effect was obtained on the maternal side with Ca2+-acetylhomotaurinate and Ca2+-taurinate. Some molecules, which have protective actions, had no opposing actions (homotaurine), or inversely (Mg2+), only Ca2+-acetylhomotaurinate exhibited both a preventive and an opposing action against ethanol. These results show the interest of studying synthetic molecules for prevention of fetal alcoholism.

Acamprosate↗
PubMed2004

Hypothetical proteins with putative enzyme activity in human amnion, lymphocyte, bronchial epithelial and kidney cell lines.

A myriad of predicted proteins have been described based upon nucleic acid sequences but the existence of these structures has not been confirmed at the protein level. The aim of the study was therefore to show expression of hypothetical proteins in several cell lines and to provide the analytical basis for their identification and characterisation. We used two-dimensional gel electrophoresis with in-gel digestion of high protein spots and subsequent MALDI-TOF analysis of cell lysates from human amnion, lymphocyte, bronchial epithelial and kidney cell lines. A pI range from 3 to 10 was selected and second dimension was run using 9-16% gradient gels. A series of structures that have not been described before at the protein level were identified in several cell lines and were assigned to major enzyme systems including proteolysis (proteases, peptidases, ubiquitin), intermediary metabolism and oxidoreductases. We conclude that the proteomic approach used serves as a suitable tool to verify the existence of predicted/hypothetical proteins. The herein identified enzymes may contribute to several pathways/cascades in the human organism. Furthermore, analytical data given are of major relevance as pIs, a prerequisite to find proteins in a map, cannot be predicted from nucleic acid sequences.

Amino Acid Sequence↗
PubMed2006

The proteolytic profile of prelabour ruptured amnion at term: a case-control study.

OBJECTIVES: The aim of this study was to investigate whether prelabour ruptured membranes at term display increased proteolytic activity and to determine whether regional structural alterations within membranes are reflective of regional variations in proteolytic activity. STUDY DESIGN: Multiple amnion samples were collected from 37 women with prelabour membrane rupture and 37 women whose membranes ruptured spontaneously during labour. In all cases the gestation was greater than 37 weeks. Substrate zymography was used to qualitatively assess gelatinase and serine protease involvement. General protease activity (metallo, serine, acid and sulfhydryl) was measured quantitatively by fluorescent substrate cleavage. RESULTS: Substrate zymography revealed no active gelatinases or serine proteases. Fluorescent studies of general protease activity showed no significant difference between the groups and no significant regional variation. CONCLUSIONS: Gelatinase and serine protease activity do not play a major role in the formation of a membrane rupture initiation site or in prelabour membrane rupture at term.

Adult↗
PubMed2004

Uncoupling of GPCR and RhoA-induced Ca2+-sensitization of chicken amnion smooth muscle lacking CPI-17.

Ca2+-sensitization of smooth muscle occurs through inhibition of myosin light chain phosphatase (MLCP) leading to an increase in the MLCK:MLCP activity ratio. MLCP is inhibited through phosphorylation of its regulatory subunit (MYPT-1) following activation of the RhoA/Rho kinase (ROK) pathway or through phosphorylation of the PP1c inhibitory protein, CPI-17, by PKC delta or ROK. Here, we explore the crosstalk between these two modes of MLCP inhibition in a smooth muscle of a natural CPI-17 knockout, chicken amnion. GTPgammaS elicited Ca2+-sensitized force which was relaxed by GDI or Y-27632, however, U46619, carbachol and phorbol ester failed to induce Ca2+-sensitized force, but were rescued by recombinant CPI-17, and were sensitive to Y-27632 inhibition. In the presence, but not absence, of CPI-17, U46619 also significantly increased GTP.RhoA. There was no affect on MYPT-1 phosphorylation at T695, however, T850 phosphorylation increased in response to GTPgammaS stimulation. Together, these data suggest a role for CPI-17 upstream of RhoA activation possibly through activation of another PP1 family member targeted by CPI-17.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗
PubMed2004

The effect of insulin-like growth factor-I on production of vascular endothelial growth factor by amnion-derived (WISH) cells.

OBJECTIVE: Our objective was to clarify the modulation of vascular endothelial growth factor (VEGF) by amniotic cells. DESIGN: Amnion-derived (WISH) cells were cultured, and the effect of insulin-like growth factor (IGF), mitogen-activated protein (MAP) kinase kinase and/or extracellular signal-regulated kinase (ERK) kinase (MEK) inhibitors (U0126), and phosphatidylinositol (PI) 3-kinase inhibitors (wortmannin) on the production of VEGF was examined. VEGF was assayed using ELISA. The activations of MAP kinase and akt, which is phosphorylated by PI 3-kinase, were detected by Western blot analysis using anti-phosphorylated MAP kinase antibody and anti-phosphorylated akt antibody. RESULTS: In the time course of VEGF production following IGF-I treatment, VEGF production showed significant increases only at 16 and 32 h (p < 0.01). Also, IGF-I increased the production of VEGF by WISH cells in a dose-dependent manner. The MAP kinase and akt activities were recognized by treatment with IGF-I and suppressed by U0126 and wortmannin, respectively. When WISH cells were pretreated for 2 h with U0126 and wortmannin and then treated with IGF-I for 16 h, the production of VEGF was significantly decreased in a dose-dependent manner (p < 0.01, p < 0.01, respectively). CONCLUSIONS: WISH cells appeared to produce VEGF via a mechanism involving tyrosine kinase interaction with IGF-I receptor, resulting in MAP kinase and PI 3-kinase activation. It is suggested that VEGF may contribute to the neovascularization and proliferation of the placenta and gestational tissue, and IGF-I may play an important role in the modulation of VEGF production in the placenta.

Amnion↗
PubMed2004

Hydrogen peroxide induced apoptosis in amnion-derived WISH cells is not inhibited by vitamin C.

Increased reactive oxygen species (ROS) have been identified as a potential cause of remodelling and apoptotic change in fetal membrane. Vitamin C has been suggested as a therapeutic agent to prevent ROS induced chorio-amnion apoptosis. The purpose of this study was to determine whether hydrogen peroxide (HP), a ROS, initiates apoptosis in the WISH cell model and whether vitamin C would inhibit HP induced apoptosis. HP induced apoptosis in WISH cells; as assessed by cytochrome-c release from mitochondria, Poly-(ADP-ribose)-Polymerase (PARP) cleavage, nuclear matrix protein (NMP) release and DNA fragmentation analysis. HP induced dose dependent release of cytochrome-c, PARP cleavage, NMP release, and DNA fragmentation. HP also increased PGE(2)release in parallel with apoptosis in WISH cells, in a manner similar to that reported with other apoptotic agents. Vitamin C pre-incubation caused cytochrome-c release earlier, and at lower HP doses, than HP alone. It had no effect on HP induced PARP cleavage, but enhanced DNA fragmentation, and induced NMP release on its own. Vitamin C partially suppressed dose dependent HP induced PGE(2)release. We conclude that HP causes apoptosis in WISH cells and vitamin C pre-incubation does not inhibit, and may accelerate and exacerbate, HP induced apoptosis.

Amnion↗
PubMed2003

Expressional pattern of chaperones in neuronal, glial, amnion, mesothelial, and bronchial epithelial cell lines.

Although literature is abundant on expression of individual heat shock proteins (HSPs) and molecular chaperones, no comprehensive information is given on their expressional pattern. The aim of our study was therefore to study expressional differences between several cell types that may provide evidence for the types of HSPs and chaperones that may be operating in the corresponding lineages. For this purpose neuronal (HCN-2), glial (SVG-p12), amnion, mesothelial (Met-5A), and bronchial epithelial (16HBE14o(-)) cell lines were grown, harvested, and protein was separated on two-dimensional electrophoresis with subsequent in-gel digestion and identification of protein spots by MALDI-MS and specific software. A series of 29 high abundance HSPs and chaperones were unambiguously identified altogether. We observed distinct expressional patterns and although overlapping, there was an apparent paucity of HSPs and chaperones in bronchial epithelial and mesothelial cells. We learn from this study that individual cell lines express and may use different HSP and chaperones systems and strategies. Specific functions of cells may be responsible as well as the presence of protein specific chaperones, although we cannot rule out that cell culture conditions were at least in part responsible for the different expressional patterns.

Amnion↗
PubMed1999

Diagnosing amnionicity at 6 weeks of pregnancy with transvaginal three-dimensional ultrasonography: case report.

OBJECTIVE: To report a case of monochorionic, diamniotic twin pregnancy diagnosed at 6 weeks of pregnancy with three-dimensional (3D) transvaginal sonography and to discuss the use of this diagnostic method in the evaluation of multifetal pregnancy in the first trimester. DESIGN: Case report. SETTING: University-based IVF program. PATIENT(S): A 30-year-old ovum recipient underwent ultrasonographic evaluation of a first-trimester twin pregnancy. INTERVENTION(S): Two-dimensional (2D) and 3D transvaginal sonography. MAIN OUTCOME MEASURE(S): Accurate diagnosis of chorionicity and amnionicity. RESULT(S): Monoamniotic pregnancy and conjoined twinning could not be ruled out by using 2D transvaginal sonography at 6 weeks, because only one yolk sac (YS) and no membranes could be visualized, and the two embryos were closely positioned within one gestational sac. Applying 3D technique, two YSs and two separate embryos could clearly be observed, establishing the correct diagnosis of a monochorionic, diamniotic pregnancy. CONCLUSION(S): The 3D transvaginal ultrasonography provides a quick and accurate diagnostic modality for the evaluation of a first-trimester multiple gestation.

Adult↗
PubMed2001

15-deoxy-delta12,14-prostaglandin J2-induced apoptosis in amnion-like WISH cells.

Apoptosis at the site of rupture has been proposed to play a role in premature rupture of the fetal membranes, a condition associated with increased risk of neonatal sepsis and preterm birth. We investigated the ability of peroxisome proliferator-activated receptor (PPAR)-gamma ligands 15-deoxy-delta12,14PGJ2 (15d-PGJ2), delta12PGJ2, ciglitizone and rosiglitazone to induce apoptosis in the amnion-like WISH cell line. 15d-PGJ2 (10 microM) induced morphological characteristics of apoptosis within 2 h, with biochemical indices (caspase activation and substrate cleavage) following shortly after; maximum cell death (approximately 60%) was observed by 16 h, with an EC50) of approximately 7 microM 15d-PGJ2. Delta12-PGJ2 also induced apoptosis but was less potent and acted at a much slower rate. While ciglitizone also induced apoptosis, rosiglitazone had no effect on cell viability. The mechanism of induction of apoptosis by 15d-PGJ2 and delta12PGJ2, which may be independent of PPAR-gamma activation, requires further elucidation.

Amino Acid Chloromethyl Ketones↗
PubMed1985

Effect of bacterial products on prostaglandin E production by amnion cells.

An in-vitro model was set up to study a possible causal relation between bacterial colonisation of extraplacental membranes and spontaneous preterm labour. When amnion cells in tissue culture were exposed to bacterial products, their prostaglandin E output rose considerably. The degree of response varied with the organism. These findings support the theory that bacterial products may be responsible for the premature onset of labour.

Amnion↗
PubMed2003

Interactions between the nitric oxide and prostaglandin E2 biosynthetic pathways in human amnion-like WISH cells.

The aim of this study was to investigate the possible relationship between prostaglandin (PG) and nitric oxide (NO) biosynthetic pathways in human amnion-like WISH cells. Our results indicate that: (1) sodium nitroprusside (SNP), a NO donor, dose-dependently increases spontaneous prostaglandin E2 (PGE2) release while it inhibits the prostanoid output induced by the inflammatory cytokine, interleukin-1beta (IL-1beta); (2) L-arginine, the substrate of nitric oxide synthase (NOS), is ineffective in both conditions; (3) IL-1beta, which greatly enhances mRNA expression for cyclooxygenase (COX)-inducible isoform (COX-2), does not modify the mRNA expression for the NOS-inducible (iNOS) isoform; (4) indomethacin, which as expected inhibits both basal and IL-1beta-induced PGE2 release, permits the expression of iNOS mRNA in the presence of the cytokine; (5) a similar permissive action on IL-1beta action is exerted by the synthetic steroid betamethasone, which is able to inhibit both mRNA COX-2 expression and IL-1beta-induced PGE2 output in WISH cells; (6) exogenous PGE2 inhibits iNOS mRNA expression induced by indomethacin plus IL-1beta treatment; and (7) PGE2 significantly increases intracellular adenosine 3',5'-cyclic monophosphate (cAMP). The results reported here suggest the existence of a relationship between the prostaglandinergic and nitridergic pathways in WISH cells. In particular, we demonstrate that exogenous NO inhibits PGE2 release evoked by IL-1beta whereas high levels of the prostanoid, in the presence of proinflammatory agents, exert a negative feed-back control on iNOS mRNA expression, possibly through a cAMP-dependent mechanism.

Amnion↗