Evaluation of kisspeptin levels in obese pregnancy as a biomarker for pre-eclampsia

OBJECTIVES

Circulating concentrations of the peptide kisspeptin have been proposed as a novel biomarker for early detection of pre-eclampsia. Our aims were to assess analytical and clinical performance characteristics of a commercial kisspeptin assay and to determine sensitivity and specificity of the test for pre-eclampsia.

DESIGN

Prospective, longitudinal study in a United Kingdom tertiary referral Antenatal Metabolic Clinic.

PATIENTS

Severely obese (body mass index, BMI > 40 kg/m(2), n = 194) and lean (BMI < 25 kg/m(2), n = 78) pregnant women.

MEASUREMENTS

A commercial kisspeptin ELISA (Phoenix Pharmaceuticals) was assessed for analytical sensitivity, specificity, precision, linearity, recovery and stability in maternal plasma samples at 16, 28 and 36 weeks gestation. Pre-eclampsia, defined using International Society for the Study of Hypertension in Pregnancy guidelines; blood pressure; delivery gestation; birthweight.

RESULTS

Kisspeptin concentrations were lower in early pregnancy in obese women (P < 0.001), and in women who later developed pre-eclampsia (P < 0.05), compared with women with uncomplicated pregnancies. For 16-week plasma kisspeptin in prediction of pre-eclampsia, area under the receiver-operator characteristic curve was 0.80 (P < 0.01), positive and negative likelihood ratios were 3.0 and 0.2, and test sensitivity and specificity were 85.7 and 71.4%, respectively. In regression analyses, kisspeptin (16 weeks) associated positively with delivery gestation (P < 0.05) and birthweight (P < 0.0001), and negatively with 28- and 36-week blood pressure (P < 0.0001).

CONCLUSIONS

Kisspeptin concentration in early pregnancy is a promising biomarker for pre-eclampsia and low birthweight but cannot be recommended, in isolation, for universal screening because of inadequate test sensitivity and specificity. Large-scale studies are required to assess its potential in a panel of biomarkers.

LKB1 is an essential regulator of spermatozoa release during spermiation in the mammalian testis

LKB1 acts as a master upstream protein kinase regulating a number of kinases involved in diverse cellular functions. Recent studies have suggested a role for LKB1 in male fertility. Male mice with reduced total LKB1 expression, including the complete absence of the major splice variant in testis (LKB1(S)), are completely infertile. We sought to further characterise these mice and determine the mechanism underlying this infertility. This involved expression studies of LKB1 in developing germ cells, morphological analysis of mature spermatozoa and histological studies of both the testis and epididymis using light microscopy and transmission electron microscopy. We conclude that a defect in the release of mature spermatids from the seminiferous epithelium (spermiation) during spermatozoan development is a major cause of the infertility phenotype. We also present evidence that this is due, at least in part, to defects in the breakdown of the junctions, known as ectoplasmic specialisations, between the sertoli cells of the testis epithelium and the heads of the maturing spermatids. Overall this study uncovers a critical role for LKB1 in spermiation, a highly regulated, but poorly understood process vital for male fertility.

Prokineticin 1 induces inflammatory response in human myometrium: a potential role in initiating term and preterm parturition

The infiltration of human myometrium and cervix with leukocytes and the formation of a pro-inflammatory environment within the uterus have been associated with the initiation of both term and preterm parturition. The mechanism regulating the onset of this pro-inflammatory cascade is not fully elucidated. We demonstrate that prokineticin 1 (PROK1) is up-regulated in human myometrium and placenta during labor. The expression of PROK1 receptor remains unchanged during labor and is abundantly expressed in the myometrium. Gene array analysis identified 65 genes up-regulated by PROK1 in human myometrium, mainly cytokines and chemokines, including IL-1β, chemokine C-C motif ligand 3, and colony-stimulating factor 3. In addition, we demonstrate that PROK1 increases the expression of chemokine C-C motif ligand 20, IL-6, IL-8, prostaglandin synthase 2, and prostaglandin E(2) and F(2α) secretion. The treatment of myometrial explants with 100 ng/mL of lipopolysaccharide up-regulates the expression of PROK1, PROK1 receptor, and inflammatory mediators. The infection of myometrial explants with lentiviral microRNA targeting PROK1, preceding treatment with lipopolysaccharide, reduces the expression of inflammatory genes. We propose that PROK1 is a novel inflammatory mediator that can contribute to the onset of human parturition at term and partially mediate premature onset of inflammatory pathways during bacterial infection.

14-3-3 proteins in plant physiology

Plant 14-3-3 isoforms, like their highly conserved homologues in mammals, function by binding to phosphorylated client proteins to modulate their function. Through the regulation of a diverse range of proteins including kinases, transcription factors, structural proteins, ion channels and pathogen defense-related proteins, they are being implicated in an expanding catalogue of physiological functions in plants. 14-3-3s themselves are affected, both transcriptionally and functionally, by the extracellular and intracellular environment of the plant. They can modulate signaling pathways that transduce inputs from the environment and also the downstream proteins that elicit the physiological response. This review covers some of the key emerging roles for plant 14-3-3s including their role in the response to the plant extracellular environment, particularly environmental stress, pathogens and light conditions. We also address potential key roles in primary metabolism, hormone signaling, growth and cell division.

A role for lipoxin A₄ as an anti-inflammatory mediator in the human endometrium

Lipoxin A(4) is a lipid mediator that elicits anti-inflammatory and pro-resolution actions via its receptor, formyl peptide receptor 2 (FPR2/ALX). In this study, we aimed to investigate the expression and potential role of lipoxin A(4) and FPR2/ALX in the regulation of inflammation associated with cyclical remodeling of the human endometrium across the menstrual cycle and during early pregnancy. Using quantitative RT-PCR analysis, we found that FPR2/ALX expression is upregulated during the menstrual phase of the cycle and in decidua tissue from the first trimester of pregnancy. We localized the site of expression of FPR2/ALX in menstrual phase endometrium and first-trimester decidua tissue to glandular epithelial cells and cells within the stromal compartment, including cells lining the blood vessels and immune cells. Measurement of serum lipoxin A(4) by ELISA revealed no difference in its levels across the menstrual cycle but an elevation in early pregnancy (P<0.001). We found that lipoxin A(4) was regulated by human chorionic gonadotrophin (hCG) during early pregnancy, because treatment of human decidua tissue with hCG increased lipoxin A(4) release (P<0.01). Finally, we have shown that lipoxin A(4) can suppress phorbol myristate acetate-induced expression of the inflammatory cytokines interleukin 6 and 8 in human endometrium and decidua tissue. These results demonstrate for the first time that lipoxin A(4) and its receptor FPR2/ALX can regulate inflammatory events in the human endometrium and decidua of early pregnancy.

The external Ballard examination does not accurately assess the gestational age of infants born at home in a rural community of The Gambia

Background

Accurate assessment of gestational age at birth is critical to the identification of neonates at high risk. In resource‐poor settings, postnatal techniques are commonly used but may be difficult to apply and have not been well validated against ultrasound in community studies. The aim of this study was to evaluate postnatal assessment of gestational age in rural Africa using the external criteria of the Ballard examination against 1st/early 2nd‐trimester ultrasound and date of last menstrual period.

Method

In a sample of women from Kiang West, The Gambia (n = 80), the precision of gestational age estimates using the external Ballard examination was compared with those derived from 1st and early 2nd‐trimester ultrasound examination and date of last menstrual period.

Results

The incidence of preterm delivery was low at 2.5%. The external Ballard examination tended to underestimate gestational age by a mean (SD) of 15.6 (10.9) days compared with that derived from ultrasound and to underestimate by 15.4 (23.1) days compared with that derived from date of last menstrual period. The differences between the methods varied with gestation.

Conclusion

In this rural, community‐born population of infants, postnatal assessment of gestational age by external Ballard examination performed poorly compared with ultrasound and last menstrual period. No reliable gestational age could be derived from its estimate and it failed to detect a significant proportion of high‐risk infants. The development of an accurate but simple method of postnatally assessing gestational age specifically for use by health workers in rural Africa is required.

CTGF expression is up-regulated by PROK1 in early pregnancy and influences HTR-8/Svneo cell adhesion and network formation

BACKGROUND

Prokineticin-1 (PROK1) and connective tissue growth factor (CTGF) are expressed in human endometrium and first-trimester decidua and have individually been proposed to have roles in implantation and placentation. We have recently demonstrated that CTGF may be a target gene for PROK1 in gene array analysis of a prokineticin receptor-1 stably transfected Ishikawa endometrial epithelial cell line (PROKR1-Ishikawa). The first aim of the study was to determine the effect of PROK1 on CTGF expression in PROKR1-Ishikawa cells and first-trimester decidua samples. Secondly, the effect of CTGF on trophoblast-derived HTR-8/SVneo cell adhesion and network formation was investigated.

METHODS AND RESULTS

Real-time qPCR showed that CTGF expression is elevated in first-trimester decidua compared with non-pregnant endometrium. In decidua, CTGF co-localized with PROKR1 to the glandular epithelium and a subset of stromal cells. PROK1 increased CTGF mRNA and protein expression in PROKR1-Ishikawa cells and first-trimester human decidua (8–12 weeks gestation). Knock down of endogenous PROK1 using micro RNA constructs targeted at PROK1, resulted in decreased expression of CTGF mRNA and protein in decidua. Inhibitors of specific cell signalling molecules demonstrated that PROK1 regulates CTGF expression via the Gq, phospholipase C (PLC), cSrc, epidermal growth factor receptor (EGFR), mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) kinase pathway activation. Treatment of trophoblast-derived HTR-8/Svneo cells with 1 µg/ml CTGF significantly increased adhesion to collagen IV, and differentiation of the cells into tube-like structures in matrigel.

CONCLUSIONS

CTGF expression in early pregnancy decidua is regulated by PROK1, via activation of the Gq, PLC, cSrc, EGFR, MAPK/ERK kinase pathway. CTGF in turn may contribute to the regulation of trophoblast conversion of maternal spiral arteries.

Enhanced angiogenic capacity of human umbilical vein endothelial cells from women with preeclampsia

Maternal and placental angiogenic abnormalities are a common feature of preeclampsia. The aim of this study was to determine if endothelial cells from women with preeclampsia exhibit different angiogenic responses compared to healthy cells. Using the endothelial tube formation assay, we have shown that primary human umbilical vein endothelial cells (HUVECs) isolated from women with preeclampsia display greater levels of in vitro angiogenic branching compared to cells from healthy women. A comparable increase in tube formation was observed in healthy cells cultured at 0.5% O(2). Vascular endothelial growth factor (VEGF) receptor inhibition resulted in a decrease in angiogenesis in both healthy hypoxic cells and cells from women with preeclampsia. These findings demonstrate that HUVECs from women with preeclampsia exhibit inherent differences in their angiogenic capacity which are apparent in the absence of placental or maternal factors.

A role for lipoxin A4 as anti-inflammatory and proresolution mediator in human parturition

The purpose of this study was to investigate the role of lipoxin A(4), an anti-inflammatory and proresolution modulator, during human parturition. We measured serum levels of lipoxin A(4) and myometrial protein release using ELISA, quantified lipoxin receptor (FPR2/ALX) mRNA expression using qRT-PCR, and localized protein expression using immunohistochemstry in myometrial biopsies from pregnant women. In addition, we compared the effects of lipoxin A(4) (100 nM) with vehicle on basal and LPS-stimulated expression of proinflammatory cytokines from samples of myometrium from pregnant women. Mean ± SE circulating level of lipoxin A(4) was 5.89 ± 0.63 nM at 24-wk gestation, with a further modest increase during pregnancy (P<0.05), but no differences in gestation matched women before and after labor (P>0.05). Levels of lipoxin A(4) in nonpregnant women were 0.48 ± 0.04 nM, significantly lower than in pregnant women (P<0.001). FPR2/ALX localized to myocytes and neutrophils, with a 9-fold increase in mRNA expression in labor (P<0.001). Lipoxin A(4) significantly reduced LPS-induced but not basal expression of the proinflammatory cytokines IL-6 and IL-8 in cultured myometrium (P<0.05), compared to vehicle-treated controls. We demonstrate for the first time a potential role for lipoxin A(4) and its receptor in the resolution of the inflammatory events of both physiological and pathological labor.

Obesity, pregnancy, inflammation, and vascular function

Maternal obesity is associated with increased morbidity and mortality for both mother and offspring. The mechanisms underlying the increased risk associated with maternal obesity are not well understood. In non-pregnant populations, many of the complications of obesity are thought to be mediated in part by inflammation and its sequelae. Recent studies suggest that a heightened inflammatory response may also be involved in mediating adverse clinical outcomes during pregnancy. This review summarizes our current knowledge about adipose tissue biology, and its role as an endocrine and inflammatory organ. The evidence for inflammation as a key mediator of adverse pregnancy outcome is also presented, focusing on the role of inflammation in adipose tissue, systemic inflammation, the placenta, and vascular endothelium.

The influence of the menstrual cycle, normal pregnancy and pre-eclampsia on platelet activation

Platelet activation has a key role in mediating thrombotic and inflammatory events. This study aimed to determine the influence of the menstrual cycle, pregnancy and pre-eclampsia on in vivo platelet activation. Twelve healthy nulliparous, non-smoking women with regular menses were studied over a single menstrual cycle. Twenty-one healthy primigravida pregnant women were studied longitudinally at 16, 24, 32 and 37 weeks gestation and seven weeks post-partum. Sixteen primigravida women with pre-eclampsia were studied at time of diagnosis and at seven weeks post-partum. Platelet-monocyte aggregates and platelet-surface P-selectin expression were assessed by flow-cytometry. Soluble P-selectin and CD40 ligand (CD40L) were measured by ELISA. Markers of platelet activation did not vary over the menstrual cycle. Platelet-monocyte aggregates were greater in the third trimester of pregnancy compared to non-pregnant women (p=0.003). Platelet surface and plasma soluble P-selectin concentrations increased with gestation (p<0.0001) and were raised by 24 weeks of pregnancy compared to non-pregnant women (p< or =0.02 for both) and together with platelet monocyte aggregates, decreased post-partum (p< or =0.02). Soluble CD40L concentrations fell in pregnancy, reaching a nadir at mid-gestation (p=0.002). There were no differences in markers of platelet activation between normal and pre-eclamptic pregnancies. In conclusion, platelet activation is increased in pregnancy and increases with gestation but is unaffected by pre-eclampsia. This suggests that systemic platelet activation is a feature of pregnancy but this is not affected by established pre-eclampsia.

Influence of the Menstrual Cycle, Pregnancy, and Preeclampsia on Arterial Stiffness

Arterial stiffness and compliance are major predictors of adverse cardiovascular events and are influenced by female sex hormones, including estrogen and progesterone. The aim of this longitudinal study was to evaluate the effect of the menstrual cycle, normal pregnancy, and preeclampsia on central and systemic arterial stiffness. Ten healthy nulliparous women with regular menses were studied in the early and midfollicular, periovulatory, and luteal phases of a single menstrual cycle. Twenty-two primigravida pregnant women were studied throughout pregnancy at 16, 24, 32, and 37 weeks gestation and at 7 weeks postpartum. Fifteen primigravida women with preeclampsia were studied at diagnosis and 7 weeks postpartum. Augmentation index and carotid-radial and carotid-femoral pulse wave velocities were measured using applanation tonometry. Augmentation index fell during the luteal phase of the menstrual cycle (luteal phase versus periovulatory phase; P <0.05). In normal pregnancy, pulse wave velocity and augmentation index increased from 24 weeks over the third trimester ( P ≤0.01 for both). All of the measures were increased in women with preeclampsia ( P ≤0.01), with augmentation index and carotid-femoral pulse wave velocity remaining elevated 7 weeks postpartum ( P ≤0.02). We conclude that systemic arterial stiffness undergoes major changes during the menstrual cycle and pregnancy and that preeclampsia is associated with greater and more prolonged increases in arterial stiffness. These effects may contribute to adverse cardiovascular outcomes of pregnancy and preeclampsia.

Acute endothelial tissue plasminogen activator release in pregnancy

OBJECTIVE

Pregnancy is associated with marked changes in vascular physiology and an increased risk of thrombosis. The aim of the study was to assess the effect of pregnancy on the acute release of tissue plasminogen activator (t-PA) from the endothelium.

METHODS AND RESULTS

Ten primigravida pregnant women were recruited in the third trimester of pregnancy (week 36 +/- 1) and compared with 20 age-matched non-pregnant women (day 9.8 +/- 0.3 of menstrual cycle). Blood flow and plasma fibrinolytic factors were measured in both forearms by venous occlusion plethysmography and blood sampling, respectively, during unilateral brachial artery infusions of bradykinin (100-1000 pmol min(-1)). Pregnant women had higher plasma plasminogen activator inhibitor type 1 (PAI-1) antigen concentrations (77.1 +/- 12.4 vs. 21.5 +/- 9.8 ng mL(-1); P = 0.004) that resulted in lower basal t-PA/PAI-1 ratios (0.2 +/- 0.1 vs. 0.6 +/- 0.1; P = 0.02) and plasma t-PA activity concentrations (0.17 +/- 0.02 vs. 0.58 +/- 0.06 IU mL(-1); P < 0.0004). In both groups, bradykinin caused dose-dependent increases in blood flow and local release of plasma t-PA antigen and activity (P < 0.005 for all). Both the plasma t-PA/PAI-1 ratios and the net release of active t-PA were markedly reduced in pregnant women (P < 0.05 for both). Area under the curve for net active t-PA release was reduced by 36%.

CONCLUSIONS

Pregnancy is associated with major perturbations of endogenous fibrinolytic capacity with an overwhelming increase in plasma PAI-1 concentrations and an inadequate release of active t-PA. These prothrombotic effects may, in part, explain the increased risk of arterial and venous thrombosis in pregnant women.

Influence of menstrual cycle on circulating endothelial progenitor cells

BACKGROUND

Endothelial progenitor cells (EPCs) are circulating mononuclear cells that participate in angiogenesis. The aim of this study was to determine the influence of the menstrual cycle on the number and function of EPCs, and to investigate their relationship with circulating concentrations of sex steroids and inflammatory mediators.

METHODS

Ten healthy nulliparous, premenopausal, non-smoking women with regular menses were studied over a single menstrual cycle. Venepuncture was performed in the menstrual, follicular, peri-ovulatory and luteal phases. EPCs were quantified by flow cytometry (CD133(+)CD34(+)KDR(+) phenotype) and the colony-forming unit (CFU-EPC) functional assay. Circulating concentrations of estradiol, progesterone and inflammatory mediators (TNF-alpha, IL-6, sICAM-1 and VEGF) were measured by immunoassays.

RESULTS

The numbers of CD133(+)CD34(+)KDR(+) cells were higher in the follicular phase (0.99 +/- 0.3 x 10(6) cells/l) compared with the peri-ovulatory phase (0.29 +/- 0.1 x 10(6) cells/l; P < 0.05). In contrast, the numbers of CFU-EPCs did not vary over the menstrual cycle. There were no correlations between EPCs and concentrations of either circulating sex steroids or inflammatory mediators.

CONCLUSIONS

CD133(+)CD34(+)KDR(+) cells but not CFU-EPCs vary during the menstrual cycle. Our findings suggest a potential role for circulating EPCs in the normal cycle of physiological angiogenesis and repair of the uterine endometrium that is independent of circulating sex steroids or inflammatory mediators.

Characterization of an alternative splice variant of LKB1

LKB1 is an upstream activating kinase for the AMP-activated protein kinase (AMPK) and at least 12 other AMPK-related kinases. LKB1 therefore acts as a master kinase regulating the activity of a wide range of downstream kinases, which themselves have diverse physiological roles. Here we identify a second form of LKB1 generated by alternative splicing of the LKB1 gene. The two LKB1 proteins have different C-terminal sequences generating a 50-kDa form (termed LKB1L) and a 48-kDa form (LKB1S). LKB1L is widely expressed in mouse tissues, whereas LKB1S has a restricted tissue distribution with predominant expression in the testis. LKB1S, like LKB1L, forms a complex with MO25 and STRAD, and phosphorylates and activates AMPK both in vitro and in intact cells. A phosphorylation site (serine 431 in mouse) and a farnesylation site (cysteine 433 in mouse) within LKB1L are not conserved in LKB1S raising the possibility that these sites might be involved in differential regulation and/or localization of the two forms of LKB1. However, we show that phosphorylation of serine 431 has no effect on LKB1L activity and that both LKB1L and LKB1S have similar patterns of subcellular localization. These results indicate that the physiological significance of the different forms of LKB1 is not related directly to differences in the C-terminal sequences but may be due to their differential patterns of tissue distribution.

Prokineticin-1: a novel mediator of the inflammatory response in third-trimester human placenta

Prokineticin-1 (PK1) is a recently described protein with a wide range of functions, including tissue-specific angiogenesis, modulation of inflammatory responses, and regulation of hemopoiesis. The aim of this study was to investigate the localization and expression of PK1 and PK receptor-1 (PKR1), their signaling pathways, and the effect of PK1 on expression of the inflammatory mediators cyclooxygenase (COX)-2 and IL-8 in third-trimester placenta. PK1 and PKR1 were highly expressed in term placenta and immunolocalized to syncytiotrophoblasts, cytotrophoblasts, fetal endothelium, and macrophages. PK1 induced a time-dependent increase in expression of IL-8 and COX-2, which was significantly reduced by inhibitors of Gq, cSrc, epidermal growth factor receptor (EGFR), and MAPK kinase. Treatment of third-trimester placenta with 40 nm PK1 induced a rapid phosphorylation of cSrc, EGFR, and ERK1/2. Phosphorylation of ERK1/2 in response to PK1 was dependent on sequential phosphorylation of cSrc and EGFR. Using double-immunofluorescent immunohistochemistry, PKR1 colocalized with IL-8 and COX-2 in placenta. These data suggest that PK1 may have a novel role as a mediator of the inflammatory response in placenta.

Maternal obesity, length of gestation, risk of postdates pregnancy and spontaneous onset of labour at term

OBJECTIVE

To investigate the effect of maternal body mass index (BMI) on postdates pregnancy, length of gestation and likelihood of spontaneous onset of labour at term.

DESIGN

Retrospective cohort study.

SETTING

Swedish Medical Birth Register.

POPULATION

A total of 186 087 primiparous women (of whom 143 519 had spontaneous onset of labour at term) who gave birth between 1998 and 2002.

METHODS

Mann-Whitney test, one-way analysis of variance, linear regression and single variable logistic regression.

MAIN OUTCOME MEASURES

Postdates pregnancy (>/=294 days or 42(+0) weeks), length of gestation and likelihood of spontaneous onset of labour at term.

RESULTS

About 6.8% of pregnancies delivered postdates. Higher maternal BMI (kg/m(2)) during the first trimester was associated with longer gestation (P < 0.001) as was a greater change in BMI between the first and third trimesters (BMI measured on admission prior to delivery) with mean (SD) gestation at delivery of 280.7 (8.6) and 283.2 (8.6) days for increases in BMI of <2 and >/=10 kg/m(2), respectively. Higher BMI during the first trimester was associated with a lower chance of spontaneous onset of labour at term. Compared with BMI 20 to <25 kg/m(2), the odds ratios (95% CI) for spontaneous onset of labour at term were 1.21 (1.15-1.27) for BMI of <20 kg/m(2), 0.71 (0.69-0.74) for BMI of 25 to <30 kg/m(2), 0.57 (0.54-0.60) for BMI of 30 to <35 kg/m(2) and 0.43 (0.40-0.47) for BMI of >/=35 kg/m(2). Higher BMI during the first trimester (BMI of >/=35 kg/m(2) compared with BMI of 20 to <25 kg/m(2)) was also associated with an increased risk of complications including stillbirth (OR 3.90, 95% CI 2.44-6.22), gestational diabetes (OR 5.61, 95% CI 4.61-6.83) and caesarean section (OR 2.39; 95% CI 2.20-2.59).

CONCLUSIONS

Higher maternal BMI in the first trimester and a greater change in BMI during pregnancy were associated with longer gestation and an increased risk of postdates pregnancy. Higher maternal BMI during the first trimester was also associated with decreased likelihood of spontaneous onset of labour at term and increased likelihood of complications.

Infant Feeding Intentions of Scottish Adolescents

Despite its health benefits, only 63% of women in Scotland will attempt to breastfeed. Our aim was to investigate future feeding intentions and attitudes in adolescents in the south east of Scotland. Of the 757 adolescents questioned, 78.8% of girls (n=430) and 61.6% of boys (n=130) stated an intention to breastfeed or to encourage their partner to breastfeed. Knowledge of being breastfed as an infant was the only factor associated with a higher Iowa Infant Feeding Attitude Score and proportion that either intend to breastfeed or support breastfeeding in the future.

Endothelial progenitor cells in pregnancy

The discovery of endothelial progenitor cells has generated considerable interest in the field of vascular biology. These cells arise from a population of circulating mononuclear cells and have the capacity to form new blood vessels and contribute to vascular repair. Circulating endothelial progenitor cell numbers are reduced in patients with cardiovascular risk factors and in the presence of endothelial dysfunction, but are increased in response to ischaemia, oestrogens and drug therapy. They have been studied in pathologies from cardiovascular and renal disease to rheumatoid arthritis and pre-eclampsia. Pregnancy is a challenge to the maternal vascular system, requiring systemic adaptation and pronounced local changes in the uterus. Diseases of pregnancy such as pre-eclampsia and gestational diabetes increase the risk of pregnancy complications and are associated with endothelial dysfunction. We propose that endothelial progenitor cells have an important role in the regulation and maintenance of the vasculature during pregnancy. This review summarises our current understanding of endothelial progenitor cells, with specific reference to their role in angiogenesis and human pregnancy.

Data-directed scan sequence for the general assignment of C-glycosylflavone O-glycosides in plant extracts by liquid chromatography-ion trap mass spectrometry

An ion trap LC-MS/MS method is described for the analysis of C-glycosylflavone O-glycosides in crude methanolic extracts of plants. The method employs survey scans with and without the application of up-front collision induced dissociation (CID) to generate diagnostic ions for data-directed MS/MS. The spectra acquired allow assignment of the C-linked sugar to either the C-6 or C-8 position of the aglycone and provide data on the molecular mass of the compound, the number and type of O-linked sugars and the molecular mass of the flavone aglycone. These data for the majority of C-glycosylflavone O-glycosides in an extract are obtained automatically in one LC-MS/MS analysis without manual pre-programming. Key to the assignment of the C-6 or C-8 site of C-glycosylation is the generation, by up-front CID, of the (0,1)X+ product ion formed by internal cleavage of the C-linked sugar. MS/MS of this ion is found to have diagnostic value in addition to the (0,2)X+ product ion described by other authors. Ion trap MS/MS spectra of [M+H]+ of the 6,8-di-C-glycosylflavones schaftoside and isoschaftoside show an additional and previously unreported diagnostic product ion that is useful in determining the type of sugar at the C-6 position. The product ion spectra of protonated kaempferol 3-O-glucosylrhamnosides show similarities to the spectra of C-glycosylflavone O-glycosides; this is a potential source of confusion if the analysis of such glycosides is limited solely to MS/MS of [M+H]+.

The effect of mifepristone administration on leukocyte populations, matrix metalloproteinases and inflammatory mediators in the first trimester cervix

Cervical ripening is analogous to an inflammatory reaction characterized by an influx of inflammatory cells and an increase in inflammatory mediators. The anti-gestogen mifepristone is highly effective in inducing cervical ripening in women throughout gestation. However, its mechanism of action is largely unknown. The aim of the study was to investigate the effect of in-vivo administration of mifepristone on inflammatory cells and mediators in the cervix. Cervical biopsies were taken from women undergoing a first trimester termination of pregnancy at 0, 6, 12, 24 and 36 h (n = 6 per group) after mifepristone administration. Biopsies were fixed for immunohistochemistry and also cultured for subsequent analysis of culture media by radioimmunoassay or enzyme-linked immunosorbent assay. After administration of mifepristone (6-24 h), there was an increase in immunostaining for leukocyte common antigen (CD45), neutrophil elastase, monocytes (CD68), and matrix metalloproteinases (MMP)-1, -8 and -9. Immunostaining for MMP-2 and tissue inhibitor of metalloproteinases (TIMP)-1, -2 and -4 were unaffected by mifepristone treatment. Secretion of monocyte chemotactic protein (MCP-1) was significantly (P < 0.05) increased from biopsies taken 6-24 h after mifepristone administration. Cervical biopsies also released interleukin-8 (IL-8), prostaglandin (PG) E(2), PGF(2alpha) and prostaglandin metabolites (PGEM and PGFM) although their secretion was unaffected by mifepristone treatment. This study suggests that mifepristone may, in part, effect cervical ripening by modulating the influx of inflammatory cells into the cervix, up-regulating MMP expression and inducing chemokine secretion by cervical tissue.