Biomedical subjects

Fiona Jordan

Publications and source records attributed to Fiona Jordan.

7 recordsLinked to original sources

PubMed2006

Leukocyte density and proinflammatory mediator expression in regional human fetal membranes and decidua before and during labor at term.

OBJECTIVES: The region of fetal membranes overlying the cervix, known as the zone of altered morphology (ZAM), is considered to be the principle site of membrane inflammatory activity and extracellular matrix remodelling. We wished to quantify the relative contribution of each area of fetal membranes to the inflammatory process of parturition. Specifically, we aimed to quantify and compare (1) leukocyte densities in three regions of fetal membranes and decidua before and during spontaneous labor at term, and (2) mRNA expression of interleukin (IL)-1beta, IL-6, IL-8, cyclo-oxygenase type 1 (COX-1), and COX-2 in three regions of fetal membranes and decidua before and during spontaneous labor at term. METHODS: Biopsies of fetal membranes and decidua were obtained from pregnant women delivered by cesarean section at term both before and during spontaneous labor (n = 8 both groups). Fetal membranes were sampled from three areas, the ZAM, midzone (MZ), and periplacental (PP) regions. Leukocytes were identified by immunohistochemistry and their density quantified. Inflammatory mediator expression was quantified using TaqMan technology (Applied Biosystems, Foster City, CA). RESULTS: There was a significantly greater density of leukocytes in (1) the PP region of membranes compared with the ZAM, and (2) the decidua compared with amnion, amniotic connective tissue, and chorion. IL-1beta, IL-6, and IL-8 mRNA expression was significantly greater in all regions following spontaneous labor compared with nonlaboring tissues. There were no regional differences in cytokine expression within the fetal membranes. Choriodecidua expressed significantly more IL-1beta mRNA than amnion. Amnion expressed more COX-2 mRNA than choriodecidua. CONCLUSIONS: All regions of fetal membranes and decidua contribute to the inflammatory process of human parturition; however, their relative contributions differ in magnitude. Although the ZAM may be specifically important for membrane rupture, it does not appear to play a key or exclusive role in the other inflammatory processes of parturition. When studying fetal membranes, it is relevant to identify and define the area sampled for consistency and comparison with other studies.

Cyclooxygenase 1↗

PubMed2005

Human placental peroxisome proliferator-activated receptor delta and gamma expression in healthy pregnancy and in preeclampsia and intrauterine growth restriction.

OBJECTIVES: Human and animal studies have demonstrated that peroxisome proliferator-activated receptors (PPARs) are important in placental development and play key roles in metabolism and inflammation. We studied placental PPARdelta, PPARgamma, and retinoid X receptor alpha (RXRalpha) expression in healthy pregnancy and in preeclampsia (PET) and intrauterine growth restriction (IUGR). METHODS AND RESULTS: Using immunocytochemistry, PPARdelta, PPARgamma, and RXRalpha were localized to the cyto- and syncytiotrophoblast and invading trophoblast columns in first and second trimester placentas. Third trimester placentas from healthy pregnancy, and in PET and IUGR, demonstrated PPARdelta, PPARgamma, and RXRalpha staining within the syncytium, and localization within isolated cells in the stroma. In uncomplicated pregnancies, PPARdelta mRNA expression (PPARdelta:18s ratio, third trimester median 0.43 [interquartile (IQ) range 0.26-0.52] vs first trimester 0.20 [0.00-0.26], P = .03) and PPARdelta protein expression (third trimester 3.94 [2.45-4.68] vs first trimester 1.29 [0.78-2.29] optical densitometry [OD] mm(2), P = .04) were higher in the third trimester than in the first trimester. There were no consistent differences in PPARdelta, PPARgamma, or RXRalpha mRNA and protein expression among PET or IUGR placentas and controls. CONCLUSION: PPARdelta expression is up-regulated between the first and third trimester, indicating a role for this nuclear receptor in placental function. We found no evidence that placental PPARdelta, PPARgamma, and RXRalpha expression is changed in PET or IUGR. This suggests that changes in total placental PPAR expression are not involved in the pathophysiology of these conditions.

Case-Control Studies↗

PubMed2004

Expression and localization of cell adhesion molecules in human fetal membranes during parturition.

There is increasing evidence to support the view that human parturition represents an inflammatory process. We have previously demonstrated that parturition is associated with leukocyte invasion and pro-inflammatory cytokine production in the cervix and myometrium. Furthermore, we have shown that several cell adhesion molecules are upregulated in these tissues during labor. In fetal membranes, previous studies have shown intercellular adhesion molecule-1 (ICAM-1) upregulation in association with labor. The role of other adhesion molecules has not been explored. The aims of this study were, therefore, to determine the expression of ICAM-1, platelet endothelial cell adhesion molecule (PECAM), vascular cell adhesion molecule (VCAM) and E-selectin in pre- and post-laboring amnion and choriodecidua and to identify cell types responsible for their expression. Biopsies of fetal membranes were obtained from pregnant women delivered by caesarean section before the onset of labor (n = 8) and following spontaneous vaginal delivery (n = 8). Cell adhesion molecules were identified using immunohistochemistry and messenger RNA expression quantified using Northern analysis. We found that following labor, ICAM-1 mRNA expression was significantly upregulated in amnion and choriodecidua (P < 0.05). PECAM mRNA expression was also increased in choriodecidua (P < 0.05). The main cell types responsible for adhesion molecule expression were leukocytes, amniotic epithelial cells and endothelial cells. The upregulation of ICAM-1 and PECAM mRNA expression in fetal membranes following labor provides further evidence that fetal membranes play an important role in the inflammatory process of parturition.

Amniotic Fluid↗

PubMed2003

Testing evolutionary hypotheses about human biological adaptation using cross-cultural comparison.

Physiological data from a range of human populations living in different environments can provide valuable information for testing evolutionary hypotheses about human adaptation. By taking into account the effects of population history, phylogenetic comparative methods can help us determine whether variation results from selection due to particular environmental variables. These selective forces could even be due to cultural traits-which means that gene-culture co-evolution may be occurring. In this paper, we outline two examples of the use of these approaches to test adaptive hypotheses that explain global variation in two physiological traits: the first is lactose digestion capacity in adults, and the second is population sex-ratio at birth. We show that lower than average sex ratio at birth is associated with high fertility, and argue that global variation in sex ratio at birth has evolved as a response to the high physiological costs of producing boys in high fertility populations.

Adaptation, Physiological↗

PubMed2003

Leukocyte density and pro-inflammatory cytokine expression in human fetal membranes, decidua, cervix and myometrium before and during labour at term.

Accumulating evidence suggests that human parturition represents an inflammatory process. Leukocytes are known to infiltrate uterine tissues but the exact timing, nature and quantity of these cells has not been formally characterized. We have previously demonstrated an apparent increase in pro-inflammatory cytokines within tissues of the labouring uterus. The aims of this study were to quantify and compare the leukocyte subpopulations before and during labour in fetal membranes, decidua and cervix and to quantify and compare mRNA expression of interleukin-1beta (IL-1beta), IL-6, IL-8 and tumour necrosis factor-alpha in myometrium, cervix, chorio-decidua and amnion. Biopsies of each of these tissues were obtained from pregnant women delivered by Caesarean section before and after the onset of spontaneous labour at term. Subpopulations of leukocytes were identified using immunohistochemistry and cytokine mRNA expression was quantified using Northern analysis. We found that parturition was associated with a significant increase in IL-1beta, IL-6 and IL-8 mRNA expression in cervix and myometrium, IL-6 and IL-8 mRNA expression in chorio-decidua and IL-1beta and IL-8 mRNA expression in amnion. Histological analysis demonstrated that leukocytes (predominantly neutrophils and macrophages) infiltrate the uterine cervix coincident with the onset of labour. These data lend further support to the hypothesis that labour is an inflammatory process.

Amnion↗

PubMed2003

Intercellular adhesion molecule-1 (ICAM-1) expression is upregulated by thrombin in human monocytes and THP-1 cells in vitro and in pregnant subjects in vivo.

Monocytes play a pivotal role in both the inflammatory and coagulation responses, which may be mediated through a variety of adhesion molecules on the cell surface, including intercellular adhesion molecule-1 (ICAM-1). Monocytes also possess thrombin receptors. In the current study, we have demonstrated that thrombin can upregulate ICAM-1 mRNA and induce ICAM-1 expression on the monocyte in vitro and that, in vivo, higher monocyte ICAM-1 expression is observed in pregnancy (which is characterised by a physiological increase in thrombin generation). In pregnant subjects, a positive correlation between monocyte ICAM-1 expression and a number of markers of vascular/thrombotic disease (including blood group, acquired activated protein C resistance and non-fasting plasma triglyceride levels) was observed. We also observed a significant relationship between monocyte ICAM-1 expression and soluble plasma ICAM-1 levels, which would be consistent with a contribution of monocytic ICAM-1 to the levels of free ICAM-1 observed in plasma during pregnancy. Consistent with a role in fibrinogen binding, our preliminary in vivo results suggest that monocyte ICAM-1 expression may be a useful marker of the thrombotic/inflammatory response, although further work is required to assess the relationship of monocyte ICAM-1 expression in thrombotic disorders.

Adult↗

PubMed2002

Immunolocalization of proinflammatory cytokines in myometrium, cervix, and fetal membranes during human parturition at term.

Each of the proinflammatory cytokines interleukin (IL)-1beta, IL-6, IL-8, and tumor necrosis factor (TNF) alpha has been identified in reproductive tissues during labor. The cellular origin of these cytokines is unclear. The aim of this study was to localize these proinflammatory cytokines in myometrium (upper and lower segment), cervix, and fetal membranes at term. Biopsies were taken from women undergoing cesarean section either before or after the onset of labor. Immunohistochemistry was used to localize each of the cytokines IL-1beta, IL-6, IL-8, and TNFalpha. Leukocytes were localized using an antibody to CD45. In myometrium and cervix, immunostaining for IL-1beta was predominantly in leukocytes. In fetal membranes, IL-1beta localized to leukocytes and to the stromal cells of the decidua. In myometrium, IL-6, IL-8, and TNFalpha were restricted to leukocytes, which were present in greater numbers in tissue obtained during labor. In cervix, IL-6, IL-8, and TNFalpha localized to leukocytes and glandular and surface epithelium. IL-8 also localized to cervical stromal cells. In fetal membranes, IL-6 and TNFalpha were expressed by decidual stromal cells, infiltrating leukocytes, and extravillous trophoblasts. In membranes, IL-8 localized to leukocytes in the chorion but was not detected in the amnion. In fetal membranes collected at labor, IL-8 was expressed in decidual stromal cells. Infiltrating leukocytes are a major source of cytokines in uterine tissues during labor.

Adult↗