Inflammasome components and ADAMTS4 in premature rupture of membranes.

Inflammation may be responsible for the development of premature rupture of membranes (PROM) including preterm PROM (PPROM) and mature PROM (MPROM). A total of four classic receptor proteins have been confirmed to assemble inflammasomes: NLR family pyrin domain containing (NLRP)1, NLRP3 and NLR family CARD­domain containing 4 (NLRC4) and absent in melanoma 2 (AIM2). The activation and expression of these receptor­modulated inflammasomes in placenta and fetal membrane of PROM pregnancies requires investigation. In addition, a disintegrin and metalloproteinase with thrombospondin motifs 4 (ADAMTS4) is a risk factor for PROM, but whether its expression is associated with inflammasome activation remains to be elucidated. In the present study, the placenta and fetal membrane tissues of patients who had suffered PPROM and MPROM and healthy pregnancies were investigated. Reverse transcription­quantitative PCR was used to determine the mRNA expression of inflammasomes and ADAMTS4. Western blotting, immunohistochemistry and ELISA were used to investigate the protein expression levels of inflammasomes and ADAMTS4. The results demonstrated that all four inflammasomes were elevated in placenta and fetal membrane of PPROMs as were mRNA and protein expression levels of IL­18 and IL­1ß (compared with controls). A further increase of inflammasomes and interleukins was observed in MPROMs compared with controls. Similar results were also observed in ADAMTS4 expression in PPROM and MPROM groups. However, immunohistochemistry results revealed no significant difference of inflammasome receptor expression in PPROMs compared with controls. Finally, a general positive correlation between ADAMTS4 and all four inflammasome receptors in placenta and fetal membrane of PPROMs and MPROMs was observed. The present study revealed that NLRP1, NLRP3, AIM2 and NLRC4 inflammasome activation in PROM was increased. Promoted ADAMTS4 level was further observed in PROM group and was significantly correlated with inflammasome expression. Inhibition of inflammasome activation may provide a therapeutic target for clinical PROM treatment.

Drastic induction of MMP-7 by cortisol in the human amnion: implications for membrane rupture at parturition.

Preterm premature rupture of fetal membranes precedes 30-40% of preterm births. Activation of matrix metalloproteases (MMPs) is the one of the major causes of extracellular matrix (ECM) degradation in membrane rupture. Increased cortisol, regenerated by 11ß-hydroxysteroid dehydrogenase 1 in the amnion at parturition, is known to participate in a number of parturition-pertinent events. However, whether cortisol has a role in the regulation of MMPs in the membranes is not known. Here, we addressed this issue using human amnion tissue, the most tensile layer of the membranes. RNA-sequencing revealed that cortisol induced MMP7 expression dramatically in amnion fibroblasts, which was confirmed by real-time quantitative RT-PCR and Western blotting analysis in cortisol-treated amnion explants and fibroblasts. Measurement of collagen IV α5 chain (COL4A5), a substrate for MMP-7, showed that cortisol reduced its extracellular abundance, which was blocked by an antibody against MMP-7. Moreover, increased MMP-7 but decreased COL4A5 abundance was observed in the amnion tissue following labor-initiated spontaneous rupture of membranes. Mechanistic studies showed that cortisol increased the phosphorylation of c-Jun and the expression of c-Fos, the 2 major components of activated protein 1 (AP-1), respectively. The knocking down of c-Fos or c-Jun significantly attenuated the induction of MMP7 expression by cortisol. Chromatin immunoprecipitation assays showed that cortisol stimulated the enrichment of c-Fos and c-Jun at the AP-1 binding site in the MMP7 promoter. The data suggest that induction of MMP7 by cortisol via AP-1 may be a contributing factor to ECM degradation in membrane rupture at parturition.-Wang, L.-Y., Wang, W.-S., Wang, Y.-W., Lu, J.-W., Lu, Y., Zhang, C.-Y., Li, W.-J., Sun, K., Ying, H. Drastic induction of MMP-7 by cortisol in the human amnion: implications for membrane rupture at parturition.

Maternal human telomerase reverse transcriptase variants are associated with preterm labor and preterm premature rupture of membranes.

OBJECTIVE: Premature aging and short telomere lengths of fetal tissues are associated with spontaneous preterm labor (PTL) and preterm premature rupture of membranes (pPROM). Maintenance of telomere length is performed by the enzyme telomerase. Human telomerase reverse transcriptase (hTERT) is a subunit of telomerase, and its dysfunction affects telomere shortening. This study assessed whether maternal or fetal genetic variations in the hTERT gene are associated with PTL or pPROM. METHODS: A case (PTL or pPROM) control (term birth) genetic association study was conducted in 654 non-Hispanic white mothers (438 term, 162 PTL, 54 pPROM) and 502 non-Hispanic white newborns (346 term, 116 PTB, 40 pPROM). Maternal and fetal DNA samples were genotyped for 23 single nucleotide polymorphisms (SNPs) within the hTERT gene. Allele frequencies were compared between cases and controls, stratified by PTL and pPROM. Maternal and fetal data were analyzed separately. RESULTS: Allelic differences in one SNP of hTERT (rs2853690) were significantly associated with both PTL (adjusted OR 2.24, 95%CI 1.64-3.06, p = 2.32e-05) and with pPROM (adjusted OR 7.54, 95%CI 3.96-14.33, p = 2.39e-07) in maternal DNA. There was no significant association between the hTERT SNPs analyzed and PTL or pPROM in the fetal samples. CONCLUSION: hTERT polymorphisms in fetal DNA do not associate with PTL or pPROM risk; however, maternal genetic variations in hTERT may play a contributory role in risk of PTL and PPROM.

Expression of matrix metalloproteinase-9 and its substrate level in patients with premature rupture of membranes.

In this study, 30 case of patients with full-term premature membrane rupture and another 30 cases of full-term delivered subject without premature rupture of membranes (PROM) were selected to explore the relationship between premature membrane rupture with matrix metalloproteinase 9 (MMP-9) and its substrate level. Results showed the plasma zinc, MMP-9 in serum and amniotic fluid increased in patients with PROM; their type IV collagen in serum and foetal membrane decreased. Increased Zinc ion concentration results in increased concentration of MMP-9, a zinc-dependent enzyme; the degradation of type IV collagen by MMP-9 might be the potential mechanism of premature rupture of membranes in full-term pregnant women.

Comparison of amniotic fluid matrix metalloproteinase-8 and cathelicidin in the diagnosis of intra-amniotic infection.

OBJECTIVE: To evaluate the association of amniotic fluid (AF) matrix metalloproteinase-8 (MMP-8) and cathelicidin concentrations with microbial invasion of the amniotic cavity (MIAC) in pregnancies with preterm prelabor rupture of the membranes or intact membranes. STUDY DESIGN: Amniocentesis was performed in 54 singleton pregnancies between 22+0 and 34+2 gestational weeks with suspected intra-amniotic infection. AF-MMP-8 was analysed by immunoassay and AF-cathelicidin by commercial ELISA. Standard biochemical methods, molecular microbiology and culture techniques were used. RESULTS: MIAC was present in 18 (33%) women. The cutoff value for the diagnosis of MIAC was 41.5 ng ml-1 for AF-MMP-8, and 11.6 ng ml-1 for AF-cathelicidin. With these cutoff values AF-MMP-8 had a sensitivity of 100%, specificity of 69%, positive predictive value of 62% and negative predictive value of 100% for MIAC. The corresponding values for AF-cathelicidin were 89, 81, 70 and 94%. CONCLUSION: The performance of AF-cathelicidin in the prediction of MIAC is comparable to AF-MMP-8.

Screening of lysyl oxidase (LOX) and lysyl oxidase like (LOXL) enzyme expression and activity in preterm prelabor rupture of fetal membranes.

OBJECTIVE: Lysyl oxidase (LOX) and LOX like enzymes (LOXL1-4) physiologically remodel extracellular matrix and pathologically contribute to cellular senescence under oxidative stress (OS). We characterized LOX and LOXL expressions and activity in human fetal membranes. METHODS: Human fetal membranes from women with uncomplicated pregnancies at term, preterm birth with intact membranes (PTB) or preterm prelabor rupture of membranes (pPROM), and in vitro fetal membranes stimulated with water-soluble cigarette smoke extract (CSE), an OS inducer, were analyzed by real-time PCR and immunohistochemistry for LOX and LOXL (1-4) expression and localization. LOX activity was measured by fluorometric assay. RESULTS: LOX gene expression was ∼2.5-fold higher in fetal membranes from pPROM compared to PTB and term (P=0.02). LOX and LOXL1, 2 and 4 were localized to both amniotic and chorionic cells, whereas LOXL3 was limited to chorion. LOX and LOXL isoform expressions were not different between CSE treated and untreated groups, while LOX activity was increased in the presence of an antioxidant (P=0.02). CONCLUSIONS: Increase of LOX expression in pPROM, an OS-related disease, and the apparent inhibition of LOX activity by CSE restored by antioxidant treatment suggest that reactive oxygen species might influence LOX-mediated tissue remodeling in fetal membranes. Balanced antioxidant supplementation during pregnancy may reduce the risk of pPROM by increasing LOX activity.

Expression of 8-oxoguanine glycosylase in human fetal membranes.

PROBLEM: The most common DNA lesion generated by oxidative stress (OS) is 7, 8-dihydro-8-oxoguanine (8-oxoG) whose excision repair is performed by 8-oxoguanine glycosylase (OGG1). We investigated OGG1 expression changes in fetal membranes from spontaneous preterm birth (PTB) and preterm premature rupture of the membranes (pPROM) and its changes in vitro in normal fetal membranes exposed to OS inducer water-soluble cigarette smoke extract (CSE). METHOD OF STUDY: DNA damage was determined in amnion cells treated with CSE by comet and FLARE assays. OGG1 mRNA expression and localization in fetal membranes from clinical specimens and in normal term membranes exposed to CSE were examined by QRT-PCR and by immunohistochemistry. RESULTS: DNA strand and base damage was seen in amnion cells exposed to CSE. OGG1 expression was 2.5-fold higher in PTB samples compared with pPROM (P = 0.045). No significant difference was seen between term and pPROM or PTB and term. CSE treatment showed a nonsignificant decrease in OGG1. OGG1 was localized to both amnion and chorion with less intense staining in pPROM and CSE-treated membranes. CONCLUSION: Increased OS-induced DNA damage predominated by 8-oxoG is likely to persist in fetal cells due to reduced availability of base excision repair enzyme OGG1. This can likely lead to fetal cell senescence associated with some adverse pregnancy outcome.

Expression profiles of fetal membrane nicotinamide adenine dinucleotide phosphate oxidases (NOX) 2 and 3 differentiates spontaneous preterm birth and pPROM pathophysiologies.

INTRODUCTION: Nicotinamide adenine dinucleotide phosphate oxidases (NOX 1-5) are enzymes that generate cellular reactive oxygen species (ROS) besides mitochondria and might be important ROS sources associated with pregnancy complications, particularly preterm premature rupture of membranes (pPROM), that has been related to ROS. OBJECTIVE: To characterize NOX enzymes expression in human fetal membranes. METHODS: Differential expression and localization of NOX isoforms in human fetal membranes collected from women with uncomplicated pregnancies at term, preterm birth (PTB) or pPROM and in vitro in normal term membranes maintained in an organ explant system stimulated with water-soluble cigarette smoke extract (wsCSE) were documented by real time PCR and immunohistochemistry. RESULTS: Fetal membranes from term deliveries, PTB and pPROM expressed NOX 2, 3 and 4 mRNAs whereas NOX 1 and 5 were not detected. NOX 2 expression was 2.3-fold higher in PTB than pPROM (p = 0.005) whereas NOX 3 was 2.2-fold higher in pPROM compared to PTB (p = 0.04). NOX 2 and 3 expressions at term mimicked pPROM and PTB, respectively. No difference in NOX 4 expression was observed among the studied groups. NOX 2, 3 and 4 were localized to both amniotic and chorionic cells. Expression of NOX 2, 3 and 4 were not significant in wsCSE-stimulated membranes compared to untreated controls. DISCUSSION/CONCLUSIONS: NOX enzymes are present in the fetal membranes and are differentially expressed in PTB and pPROM. Absence of any changes in NOXs expression after wsCSE stimulation suggests ROS generation in the membranes does not always correlate with NOX expression.

The role of apoptosis in preterm premature rupture of the human fetal membranes.

PURPOSE: The present study was designed to examine apoptotic cell death via the caspase-dependent pathway in human fetal membranes. METHODS: Amniotic membrane samples were collected from three groups of women: group 1, women with preterm premature rupture of fetal membranes (PPROM) after cesarean delivery (n = 10), group 2, women with preterm labor (PTL) with intact membranes after cesarean delivery (n = 9) and group 3, women with term labor and vaginal delivery after an uncomplicated pregnancy (controls) (n = 11). RESULTS: Active caspase-3 immunopositivity (ACPI) of the PPROM group was significantly higher than that of the control group (p < 0.05). ACPI was higher in the PTL with intact membranes group as compared to the control group; however, it did not reach statistical significance (p > 0.05). CONCLUSION: Active caspase-3 positivity is increased in the fetal membranes of those women with PPROM.

Amniotic fluid myeloperoxidase in pregnancies complicated by preterm prelabor rupture of membranes.

OBJECTIVE: To determine amniotic fluid myeloperoxidase concentration in women with preterm prelabor rupture of the membranes with microbial invasion of the amniotic cavity and histological chorioamnionitis. METHODS: One hundred eighty-one women with singleton pregnancies with a gestational age between 24+0 and 36+6 weeks were included in this study. Amniocenteses were performed, and myeloperoxidase concentration in the amniotic fluid was determined using ELISA. RESULT: Women with microbial invasion of the amniotic cavity had higher median myeloperoxidase concentration than women without this condition (149.2 ng/mL vs. 54.6 ng/mL; p = 0.0006). Women with the presence of histological chorioamnionitis had higher median myeloperoxidase concentration than women without histological chorioamnionitis (103.7 ng/mL vs. 50.0 ng/mL; p = 0.0001). The presence of both microbial invasion of the amniotic cavity and histological chorioamnionitis was associated with higher median myeloperoxidase concentration (456.0 ng/mL vs. 52.9 ng/mL; p < 0.0001). The results remained significant after adjusting for gestational age. CONCLUSIONS: Increased amniotic fluid myeloperoxidase in microbial invasion of the amniotic cavity and histological chorioamnionitis confirm a role of myeloperoxidase in preterm prelabor rupture of the membranes pathophysiology.

Abnormal fetomaternal glucocorticoid metabolism in the background of premature delivery: placental expression patterns of the 11ß-hydroxysteroid dehydrogenase 2 gene.

OBJECTIVE: During pregnancy, 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2) is involved in the development of the placental barrier, and its main function is to protect the fetus from the effects of the physiological increase of maternal glucocorticoids. We compared human placental gene expression patterns of 11ß-HSD2 from pregnancies that ended with preterm delivery versus full term pregnancies as controls. STUDY DESIGN: We used real-time PCR to assess the placental gene expression patterns of 11ß-HSD2 in 104 preterm and 140 full term pregnancies (control group) at the time of delivery. RESULTS: In the preterm delivery group, the proportion of smokers was 26.9%, significantly higher than in the control group. Preterm delivery began with premature rupture of membranes in 70.2% and spontaneous uterine activity in 29.8%. The 11ß-HSD2 gene was underexpressed in the preterm delivery group compared to normal pregnancy between 28 and 36 gestational weeks, but unchanged between 24 and 28 weeks. There was no fetal gender effect on 11ß-HSD2 gene expression. CONCLUSION: The reduced activity of the 11ß-HSD2 gene seen in the preterm delivery group may impair fetal defences against maternal glucocorticoid exposure. In cases of impending premature delivery, glucocorticoid effects, potentially including postnatal neurological abnormalities and growth restriction, may be worsened by prophylactic steroids given to accelerate fetal lung maturity. The impairment in fetal defences against maternal glucocorticoids due to reduced 11ß-HSD2 enzyme activity appears to begin after gestational week 28.

IL-6 trans-signaling system in intra-amniotic inflammation, preterm birth, and preterm premature rupture of the membranes.

Classic IL-6 signaling is conditioned by the transmembrane receptor (IL-6R) and homodimerization of gp130. During trans-signaling, IL-6 binds to soluble IL-6R (sIL-6R), enabling activation of cells expressing solely gp130. Soluble gp130 (sgp130) selectively inhibits IL-6 trans-signaling. To characterize amniotic fluid (AF) IL-6 trans-signaling molecules (IL-6, sIL-6R, sgp130) in normal gestations and pregnancies complicated by intra-amniotic inflammation (IAI), we studied 301 women during second trimester (n = 39), third trimester (n = 40), and preterm labor with intact (n = 131, 85 negative IAI and 46 positive IAI) or preterm premature rupture of membranes (PPROM; n = 91, 61 negative IAI and 30 positive IAI). ELISA, Western blotting, and real-time RT-PCR were used to investigate AF, placenta, and amniochorion for protein and mRNA expression of sIL-6R, sgp130, IL-6R, and gp130. Tissues were immunostained for IL-6R, gp130, CD15(+) (polymorphonuclear), and CD3(+) (T cell) inflammatory cells. The ability of sIL-6R and sgp130 to modulate basal and LPS-stimulated release of amniochorion matrix metalloprotease-9 was tested ex vivo. We showed that in physiologic gestations, AF sgp130 decreases toward term. AF IL-6 and sIL-6R were increased in IAI, whereas sgp130 was decreased in PPROM. Our results suggested that fetal membranes are the probable source of AF sIL-6R and sgp130. Immunohistochemistry and RT-PCR revealed increased IL-6R and decreased gp130 expression in amniochorion of women with IAI. Ex vivo, sIL-6R and LPS augmented amniochorion matrix metalloprotease-9 release, whereas sgp130 opposed this effect. We conclude that IL-6 trans-signaling molecules are physiologic constituents of the AF regulated by gestational age and inflammation. PPROM likely involves functional loss of sgp130.

Matrix metalloproteinase-8 in cervical fluid in early and mid pregnancy: relation to spontaneous preterm delivery.

OBJECTIVE: To evaluate whether matrix metalloproteinase-8 (MMP-8) concentrations in cervical fluid in early and mid pregnancy are associated with subsequent preterm delivery (PTD) preceded by premature preterm rupture of membranes (PPROMs) or preterm labour (PTL) with intact membranes. METHODS: Cervical swab samples were collected from 5180 women in early and mid pregnancy. MMP-8 was determined by immunofluorometric assay (IFMA). The outcome measure was spontaneous PTD at < 37 weeks' gestation. RESULTS: The overall distribution and the median cervical fluid MMP-8 concentrations in early and mid pregnancy did not differ in women with term delivery and those with subsequent PTD. However, cervical fluid MMP-8 levels were lower in mid pregnancy in women with PTD preceded by PPROM at < 37 weeks as compared with women who delivered at term and women who had PTD initiated by spontaneous onset of labour (p = 0.016 and p = 0.023, respectively). CONCLUSION: Our data suggest that molecular mechanisms underlying PTL and PPROM differ and MMP-8 in cervical fluid may reflect different functions of this protease. Due to remarkable overlapping of cervical fluid MMP-8 values, this molecule may not have clinical applicability as a biomarker in cervical fluid at least among asymptomatic women in early and mid pregnancy.

The impact of vitamin C supplementation in pregnancy and in vitro upon fetal membrane strength and remodeling.

Generation of reactive oxygen species (ROS) has been suggested as a mechanism of fetal membrane (FM) weakening leading to rupture, particularly with preterm premature rupture of the fetal membranes (PROM). In vitro, FM incubation with tumor necrosis factor (TNF) mimics physiological FM weakening, concomitant with generation of ROS and collagen remodeling. Proinflammatory cytokines are also postulated to have a role in the development of the FM physiological weak zone where rupture normally initiates in-term gestations. We hypothesized that antioxidant treatment may block ROS development and resultant FM weakening. Two studies examining antioxidant effects upon FM strength were conducted, one in vivo and the other in vitro. Fetal membrane of patients enrolled in a multicenter placebo-controlled trial to determine the effect of vitamin C (1 g/day) and vitamin E (400 IU/day) upon complications of pre-eclampsia were examined for FM biomechanical properties and biochemical remodeling at birth. Separately, biomechanics and biochemical markers of remodeling were determined in FM fragments incubated with TNF with or without vitamin C preincubation. Supplemental dietary vitamin C in combination with vitamin E did not modify rupture strength, work to rupture, or matrix metalloproteinase-9 (MMP9; protein or activity) either within or outside the term FM physiological weak zone. In vitro, TNF decreased FM rupture strength by 50% while increasing MMP9 protein. Vitamin C did not inhibit these TNF-induced effects. Vitamin C alone had a weakening effect on FM in vitro. We speculate that vitamin C supplementation during pregnancy will not be useful in the prevention of preterm PROM.

Mitochondrial manganese superoxide dismutase mRNA expression in human chorioamniotic membranes and its association with labor, inflammation, and infection.

OBJECTIVE: Human parturition is characterized by the activation of genes involved in acute inflammatory responses in the fetal membranes. Manganese superoxide dismutase (Mn SOD) is a mitochondrial enzyme that scavenges reactive oxygen species (ROS). Mn SOD is up-regulated in sites of inflammation and has an important role in the down-regulation of acute inflammatory processes. Therefore, the aim of this study was to determine the differences in Mn SOD mRNA expression in the fetal membranes in patients with term and preterm labor (PTL) as well as in acute chorioamnionitis. STUDY DESIGN: Fetal membranes were obtained from patients in the following groups: (1) term not in labor (n = 29); (2) term in labor (n = 29); (3) spontaneous PTL with intact mebranes (n = 16); (4) PTL with histological chorioamnionitis (n = 12); (5) preterm prelabor rupture of the membranes (PPROM; n = 17); and (6) PPROM with histological chorioamnionitis (n = 21). Mn SOD mRNA expression in the membranes was determined by quantitative real-time reverse transcription-polymerase chain reaction. RESULTS: (1) Mn SOD mRNA expression was higher in the fetal membranes of patients at term in labor than those not in labor (2.4-fold; p = 0.02); (2) the amount of Mn SOD mRNA in the fetal membranes was higher in PTL than in term labor or in PPROM (7.2-fold, p = 0.03; 3.2-fold, p = 0.03, respectively); (3) Mn SOD mRNA expression was higher when histological chorioamnionitis was present both among patients with PPROM (3.8-fold, p = 0.02) and with PTL (5.4-fold, p = 0.02) than in patients with these conditions without histological chorioamnionitis; (4) expression of Mn SOD mRNA was higher in PTL with chorioamnionitis than in PPROM with chorioamnionitis (4.3-fold, p = 0.03). CONCLUSION: The increase in Mn SOD mRNA expression by fetal membranes in term labor and in histological chorioamnionitis in PTL and PPROM suggests that the fetus deploys anti-oxidant mechanisms to constrain the inflammatory processes in the chorioamniotic membranes.

Tocilizumab inhibits interleukin-6-mediated matrix metalloproteinase-2 and -9 secretions from human amnion cells in preterm premature rupture of membranes.

BACKGROUND/AIMS: In the present study, we investigated the participation of inflammatory cytokine-induced mediated matrix metalloproteinase (MMP) expressions and inhibition of interleukin (IL)-6-induced MMP secretion in amniotic epithelial cells by tocilizumab. METHODS: To investigate the role of MMP expressions, immunohistochemical staining was performed using membranes obtained from 10 patients with preterm premature rupture of membranes (PPROM) and from 10 patients who underwent a nonlabor cesarean section. We also investigated the regulation of MMP expression by inflammatory cytokines in human amnion cells. RESULTS: Immunohistochemical staining showed a significantly higher expression of MMP-2 and -9 in PPROM. Treatment of cultured WISH and primary amniotic epithelial cells with 10(-8) or 10(-7)M IL-6 or tumor necrosis factor (TNF)-alpha clearly increased the secretion of MMP-2 and -9. Treatment with 10(-8)M TNF-alpha or IL-6 significantly increased the invasion of WISH or primary amniotic epithelial cells, respectively, compared with the control. At a low concentration of 1 microg/ml, tocilizumab (anti-human IL-6 receptor monoclonal antibody) inhibited the IL-6-induced MMP secretion. CONCLUSIONS: This paper is the 1st report of tocilizumab inhibiting IL-6-induced MMP-2 and MMP-9 secretions from human amnion cells in PPROM.

[The assessment of neutrophil elastase measurements usefulness in pregnant women with premature rupture of fetal membranes and chorioamnionitis suspicion]. / Ocena przydatnosci oznaczania elastazy neutrofilowej u ciezarnych z przedwczesnym peknieciem blon plodowych w przypadkach podejrzanych o subkliniczna infekcje wewnatrzowodniowa.

OBJECTIVES: The evaluation of neutrophil elastase (NE) levels and its usefulness in pregnant women with premature rupture of foetal membranes (PROM) and chorioamnionitis suspicion. MATERIAL AND METHODS: We evaluated the relationship between maternal plasma and amniotic fluid NE levels with the presence of chorioamnion infection in sixty pregnant women, divided into two groups--with and without PROM. The diagnostic performance of NE evaluations in discrimination of suspected intraamniotic infection was calculated. RESULTS: NE levels in PROM patients are significantly higher than in the control group (p < 0.000001). Significantly higher NE concentrations are also observed in the case of chorioamnionitis. Moreover, if at least two clinical markers of infection were present, the diagnostic value of amniotic fluid NE levels proved to be 100% sensitive and of 100% negative predictive value. CONCLUSIONS: NE levels may be used as clinical markers which enable the obstetricians to exclude chorioamnionitis.

A single nucleotide polymorphism in the promoter of the LOXL1 gene and its relationship to pelvic organ prolapse and preterm premature rupture of membranes.

Pelvic organ prolapse and preterm premature rupture of membranes, the 2 conditions which have in common weakening of the tensile strength of tissues, are thought to be caused, in part, by abnormal extracellular matrix synthesis and/or catabolism. We identified a new single nucleotide polymorphism (NT_010194(LOXL1):g.45008784A>C) in the promoter of the LOXL1 gene, which is essential for elastin synthesis. Promoter studies showed that the minor "C'' allele had significantly greater activity than the major "A'' allele. Case-control studies examined the association of the alleles of this single nucleotide polymorphism with pelvic organ prolapse and preterm premature rupture of membranes. When comparing allele frequencies and genotypes in pelvic organ prolapse cases versus controls, no significant associations were found. A case-control study conducted in African American neonates also found no significant associations between the promoter alleles and preterm premature rupture of membranes. We conclude that a functional single nucleotide polymorphism exists in the promoter region of the LOXL1 gene. Association studies suggest that the promoter single nucleotide polymorphism does not contribute significantly to risk of pelvic organ prolapse or preterm premature rupture of membranes.

Cervicovaginal matrix metalloproteinase-9 and cervical ripening in human term parturition.

OBJECTIVE: To investigate the changes of matrix metalloproteinase-9 (MMP-9) in cervicovaginal fluid during pregnancy and its association with parturition. STUDY DESIGN: A prospective study was conducted on nulliparous women between 16 and 42 weeks with normal singleton pregnancies in the following categories: (1) preterm control (n=39); (2) term labor induction without labor or rupture of membranes (n=68); (3) term spontaneous labor with intact membranes (n=42); (4) term premature rupture of membranes (n=24). The MMP-9 concentration in the cervicovaginal fluid was measured by immunoassay. RESULTS: (1) Cervicovaginal MMP-9 did not change significantly with advancing gestation until 37 weeks, and significantly increased after 37 weeks. (2) Cervicovaginal MMP-9 levels were similar in women with no labor, spontaneous labor, and premature rupture of membranes at term. (3) For the induced labor group, a high Bishop score (>or=4) was significantly correlated with cervicovaginal MMP-9. However, an elevated cervicovaginal MMP-9 did not predict achieving active phase of labor or vaginal delivery after labor induction. CONCLUSION: Cervicovaginal MMP-9 correlated with cervical ripening before labor at term. However, cervicovaginal MMP-9 did not change with spontaneous labor or rupture of membranes at term and did not predict success of labor induction.

Visfatin/Pre-B cell colony-enhancing factor in amniotic fluid in normal pregnancy, spontaneous labor at term, preterm labor and prelabor rupture of membranes: an association with subclinical intrauterine infection in preterm parturition.

OBJECTIVE: Visfatin, a novel adipokine originally discovered as a pre-B-cell colony enhancing factor, is expressed by amniotic epithelium, cytotrophoblast, and decidua and is over-expressed when fetal membranes are exposed to mechanical stress and/or pro-inflammatory stimuli. Visfatin expression by fetal membranes is dramatically up-regulated after normal spontaneous labor. The aims of this study were to determine if visfatin is detectable in amniotic fluid (AF) and whether its concentration changes with gestational age, spontaneous labor, preterm prelabor rupture of membranes (preterm PROM) and in the presence of microbial invasion of the amniotic cavity (MIAC). METHODS: In this cross-sectional study, visfatin concentration in AF was determined in patients in the following groups: 1) mid-trimester (n=75); 2) term not in labor (n=27); 3) term in spontaneous labor (n=51); 4) patients with preterm labor with intact membranes (PTL) without MIAC who delivered at term (n=35); 5) patients with PTL without MIAC who delivered preterm (n=52); 6) patients with PTL with MIAC (n=25); 7) women with preterm PROM without MIAC (n=26); and 8) women with preterm PROM with MIAC (n=26). Non-parametric statistics were used for analysis. RESULTS: 1) The median AF concentration of visfatin was significantly higher in patients at term than in mid-trimester; 2) Among women with PTL who delivered preterm, the median visfatin concentration was significantly higher in patients with MIAC than those without MIAC; 3) Similarly, patients with PTL and MIAC had a higher median AF visfatin concentration than those with PTL who delivered at term; 4) Among women with preterm PROM, the median AF visfatin concentration was significantly higher in patients with MIAC than those without MIAC. CONCLUSIONS: 1) Visfatin is a physiologic constituent of AF; 2) The concentration of AF visfatin increases with advancing gestational age; 3) AF visfatin concentration is elevated in patients with MIAC, regardless of the membrane status, suggesting that visfatin participates in the host response against infection.