Suzanne Campbell

Plasma from preeclamptic women stimulates decidual endothelial cell growth and prostacyclin but not nitric oxide production: close correlation of prostacyclin and thromboxane production.

Objective: To examine the effect of plasma from preeclamptic women on production of the vasoactive substances prostacyclin, thromboxane, nitric oxide, and cyclic guanosine monophosphate (cGMP) by decidual endothelial cells; to determine any effects on cell growth and health; and to examine whether cells from preeclamptic women are activated compared with cells from normal women. Methods: Decidual endothelial cells from normal and preeclamptic women were incubated for 24 hours in media containing 10% plasma from preeclamptic women or matched normal women. Prostacyclin and thromboxane production was measured, as was nitric oxide and cGMP production after a further 45-minute generation period in 2% test plasma. Cell numbers and lactate dehydrogenase release were also determined. Results: In plasma from preeclamptic women, cells grew significantly faster (P < .05), prostacyclin production was increased (P < .05), and lactate dehydrogenase release was reduced (P < .01). Production of thromboxane, nitric oxide, and cGMP was not significantly affected. Decidual endothelial cells from preeclamptic women had increased growth (P < .0001) and produced more prostacyclin (P < .05) and nitric oxide (P < .001) than normal decidual endothelial cells. There were highly significant correlations between prostacyclin and thromboxane production for incubations in plasmas from preeclamptic women and between background levels of prostacyclin in each plasma from preeclamptic women and the prostacyclin produced in incubations containing that plasma (P < .0001). Conclusion: We found that plasma from preeclamptic women contained a factor that stimulated endothelial cell growth and regulated production of related amounts of prostacyclin and thromboxane. The plasma level of this factor appeared to be related to background levels of prostacyclin. The results also indicated that decidual endothelial cells from preeclamptic women were in a relatively activated state.

Interaction of Cocultured Decidual Endothelial Cells and Cytotrophoblasts in Preeclampsia

Abstract Disturbed cell-cell communication between trophoblasts and the maternal endothelium may be responsible for the deficient endovascular invasion seen in preeclampsia. In vitro studies have been hampered by lack of suitable models to directly examine interactions between these cell types. Using a bilayer coculture model, we examined the effect of decidual endothelial cells on matrix metalloproteinase secretion and the migration of cytotrophoblasts from preeclamptic pregnancies. Cells were incubated on semipermeable membranes in 20% or 2% O2 with or without the tumor promoter phorbol 12-myristate 13-acetate, which activates matrix metalloproteinase-2 and -9 in endothelial cells. Cytotrophoblasts from preeclamptic pregnancies secreted significantly less matrix metalloproteinase-2 and -9 than their normal counterparts. Although decidual endothelial cells downregulated cytotrophoblast migration in normal pregnancy, this was not observed in cocultures with cytotrophoblasts from preeclamptic pregnancies. In addition, cytotrophoblasts from preeclamptic pregnancies altered phorbol myristate acetate-induced activation of endothelial matrix metalloproteinases. Hypoxia increased cytotrophoblast migration when cells were incubated alone but not in coculture with decidual endothelial cells due to increased adhesion between the two cell types. These results suggest dysfunctional interactive regulation of migration and matrix metalloproteinase secretion in preeclampsia that could result in abnormal endovascular trophoblast invasion of the maternal vasculature.

Effect of serum on secreteion of prostacyclin and endothelin-1 by decidual endothelial cells from normal and preeclamptic pregnancies☆

OBJECTIVE Increasing circumstantial evidence suggests that the maternal endothelial cell is centrally involved in the syndrome of preeclampsia, and a number of reports have described the presence of a factor(s) that alters endothelial cell function in serum from women with preeclampsia. We have previously described differences between endothelial cells from the decidual vascular bed and those from the umbilical vein. The purposes of this study were (1) to examine the effect of serum from normal and preeclamptic women on secretion of vasoactive substances by maternal decidual endothelial cells, (2) to compare these results with those from umbilical vein endothelial cells, widely used as a surrogate for endothelial cells in general, (3) to compare responses to these sera by decidual endothelial cells from normal and preeclamptic pregnancies, and (4) to determine whether these responses are amplified by preincubation in test sera. STUDY DESIGN Endothelial cells were isolated from umbilical veins and from decidual biopsy specimens collected at caesarean section delivery, from both normal and preeclamptic women. Cells were maintained in culture until passage 2, when secretion by the three endothelial cell populations of the vasodilator prostacyclin (measured as its stable metabolite, 6-keto-prostaglandin F1 alpha) and the vasoconstrictor endothelin-1 was compared in the presence of serum from preeclamptic or gestational age-matched normal pregnant women. RESULTS Prostacyclin secretion by all endothelial cell populations was higher in the presence of serum from preeclamptic women than in medium containing serum from gestational age-matched normal pregnant women. Values for endothelin were not significantly different in cells incubated in serum from normal or preeclamptic women. Preincubation of decidual cells from preeclamptic women in test serum, particularly in preeclamptic serum, resulted in more marked stimulation of prostacyclin secretion. CONCLUSIONS Preeclamptic serum contains a factor(s) that stimulates prostanoid secretion from endothelial cells. This effect was observed in both umbilical vein and decidual cells. Cells from preeclamptic women were more susceptible to perturbation of their secretion by this factor. Serum from preeclamptic women did not specifically affect endothelin-1 secretion.

A novel in vitro co‐culture system for the study of maternal decidual endothelial cell–trophoblast interactions in human pregnancy

Investigation of the pathophysiology of pre‐eclampsia (characterised by insufficient invasion of the intrauterine vasculature by cytotrophoblasts) has been hampered by the absence of a suitable animal model, and ethical constraints in clinical studies. We have developed a novel in vitro human cell co‐culture system allowing direct assessment of cytotrophoblast invasion of a decidual endothelial cell monolayer from the abluminal side, as occurs in vivo. This model will facilitate detection, at the cellular level, of abnormal endothelial cell–trophoblast functional interactions in pre‐eclampsia and other pregnancy disorders with abnormal placentation.

Effects of Hypoxia on Regulation of Prostanoid Production in Decidual Endothelial Cells in Normal and Preeclamptic Pregnancy

Objectives: To examine the effect on prostacyclin and thromboxane prodution of incubating decidual endothelial cells under hypoxic conditions, comparing cells from normal and preeclamptic pregnancies. Furthermore, to determine whether hypoxia is deleterious to cell growth, and test the effect of stimulation and inhibition on prostanoid production. Methods: Decidual endothelial cells were exposed for a total of 40 hours to normoxic (20% O2) or hypoxic (2% O2) conditions. Prostacyclin and thromboxane secretion over the final 24 hours of incubation was measured and cell numbers after incubation determined. Lipopolysaccharide (LPS) (1.0 μg/mL) was used as a stimulator and pirmagrel (1.0 μmol/L) and tranylcypromine (10.0 μmol/L)_ as prostanoid synthase inhibitors. Results: Incubations in hypoxia resuulted in increased thromboxane (P < .05) but no change in prostacyclin production. This thromboxane increase was abrogated by pirmagrel. LPS caused significant stimulation of prostacyclin and thromboxane secretion and both LPS and hypoxia resulted in lower cell numbers. Decidual endothelial cells from normal and preeclamptic pregnancies were generally not different. Conclusions: This study indicates that in preeclampsia, where decidual endothelial cells are in a relatively more hypoxic environment, thromboxane production by these cells is likely to be increased and the prostacyclin/thromboxane ratio decreased. The thromboxane synthase inhibitor, pirmagrel, was able to reverse this abnormal increased secretion of thromboxane in vitro.

Secretion of prostaglandins and endothelin-1 by decidual endothelial cells from normal and preeclamptic pregnancies: comparison with human umbilical vein endothelial cells.

OBJECTIVE An increasing amount of circumstantial evidence points to the maternal endothelial cell as centrally involved in the syndrome of preeclampsia. The purposes of this study were (1) to compare the secretion of vasoactive substances by maternal decidual endothelial cells with that of umbilical vein endothelial cells, widely used as a surrogate for endothelial cells in general, and (2) to compare secretion of the same vasoactive substances by decidual endothelial cells from normal and preeclamptic pregnancies. STUDY DESIGN Endothelial cells were isolated from umbilical veins and from decidual biopsy specimens collected at cesarean section delivery from both normal and preeclamptic women. Cells were maintained in culture until passage 2, when secretion by the three endothelial cell populations of the vasodilators prostaglandin E2 and prostacyclin and the vasoconstrictor endothelin-1 was examined. In addition to control incubations, their responses to stimulation and suppression of secretion were compared. RESULTS In control incubations normal decidual endothelial cells secreted lower amounts of prostacyclin, prostaglandin E2, and endothelin than did human umbilical vein endothelial cells. All cell types had qualitatively similar responses to the stimuli used, but quantitatively different responses were noted between human umbilical vein endothelial cells and normal decidual endothelial cells for all metabolites examined. Preeclamptic decidual endothelial cells secreted significantly more prostaglandin E2 than did normal decidual endothelial cells in response to stimulation. CONCLUSIONS We have delineated levels of secretion of vasoactive substances by human late pregnancy decidual endothelial cells and their responses to manipulation of secretory pathways. There are differences between this endothelial cell population and human umbilical vein endothelial cells (which are widely used as a surrogate for maternal endothelial cells). The differences between normal and preeclamptic decidual endothelial cells in prostaglandin E2 secretion may point to altered regulation of arachidonic acid metabolic pathways in preeclampsia.

In vitro human decidual endothelial cell thromboxane secretion in preeclampsia Is not abnormal

OBJECTIVES The aims of this study were to describe levels of thromboxane secretion by decidual endothelial cells from normal pregnancies and to determine whether decidual endothelial cell secretion of thromboxane, implicated in the causation of the hypertension and vasoconstriction of preeclampsia, is increased in this disorder. METHODS We measured thromboxane generation by cultured decidual endothelial cells from 13 normal pregnancies (NDEC) and 13 pregnancies complicated by preeclampsia (PEDEC), compared with a control population of 6 normal human umbilical vein endothelial cells (HUVEC). Responses to stimulation by bacterial lipopolysaccharide (LPS), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1 beta (IL-1 beta) were examined. MAIN OUTCOME MEASURES Thromboxane B2 levels in supernatants of cultured endothelial cells. RESULTS The level of secretion over 24 h in culture by NDEC [14 (7-26) pg/10(6) cells] was approximately 25% that of HUVEC [63 (49-70) pg/10(6) cells]. Levels achieved in response to all stimuli examined were consistently lower in NDEC than in HUVEC (p < 0.01). Proportional stimulation by LPS and TNF-alpha was comparable in HUVEC and NDEC, whereas NDEC displayed a greater increase (25-fold) than HUVEC (10-fold) in response to IL-1 beta (p < 0.01). There were no significant differences between decidual endothelial cells from normotensive and preeclamptic women in basal secretion of thromboxane or in responses to the stimuli examined. CONCLUSIONS In vitro thromboxane secretion by decidual endothelial cells is lower than that of HUVEC, and responsiveness to specific stimuli may be quantitatively different. These findings emphasize the importance of examining endothelial cells from the involved maternal vascular bed if intrauterine vascular pathophysiological events are to be clarified. No significant differences were noted in decidual endothelial cell thromboxane secretion between normal and preeclamptic subjects.