Pleiotropic actions of forskolin result in phosphatidylserine exposure in primary trophoblasts.

Forskolin is an extract of the Coleus forskholii plant that is widely used in cell physiology to raise intracellular cAMP levels. In the field of trophoblast biology, forskolin is one of the primary treatments used to induce trophoblastic cellular fusion. The syncytiotrophoblast (ST) is a continuous multinucleated cell in the human placenta that separates maternal from fetal circulations and can only expand by fusion with its stem cell, the cytotrophoblast (CT).

Fibrocyte-like cells from intrauterine growth restriction placentas have a reduced ability to stimulate angiogenesis.

Intrauterine growth restriction (IUGR) is a common complication of pregnancy whereby the fetus fails to achieve its genetic growth potential. Malformation of the placental vasculature is observed in IUGR and may be due to the development of the placenta in a chronically hypoxic environment. Recently, we identified that the predominant stromal cells in the angiogenic zones of the placenta are fibrocyte-like cells.

Differential proteomic analysis of highly purified placental cytotrophoblasts in pre-eclampsia demonstrates a state of increased oxidative stress and reduced cytotrophoblast antioxidant defense.

Proteomics were performed using highly (99.99%) purified cytotrophoblasts from six normal and six pre-eclamptic placentas. Eleven proteins were found which decreased in pre-eclampsia (actin, glutathione S-transferase, peroxiredoxin 6, aldose reductase, heat shock protein 60 (Hsp60), two molecular forms of heat shock protein 70 (Hsp70) β-tubulin, subunit proteasome, ezrin, protein disulfide isomerase, and phosphoglycerate mutase 1).

Invasion of the leukocytes into the fetal-maternal interface during pregnancy.

No other organ in the body undergoes such an invasion of selective cells (leukocytes) and release of homing molecules, CAMs, proinflammatory cytokines, and mediators or undergoes similar extensive remodeling of tissues over such a short period of time as the pregnant uterus. This is especially interesting, as an infectious process involving microorganisms does not exist in a healthy pregnancy and delivery. Furthermore, after delivery of the baby and placenta, the uterus involutes and returns to its normal monthly cycling, and most of the leukocytes are swept away or leave.

Isolation of non-activated monocytes from human umbilical cord blood.

Problem: Methods for monocyte purification are common but few work with umbilical cord monocytes that do not activate the cell for subsequent culture analysis.

Methods Of Study: The collection procedure avoids use of needles and procedures that variably activate blood clotting and uses a purification procedure that involves diluted Ficoll, autologous serum to remove platelets and 42% and 51% Percoll step gradients for the final purification. The resulting monocytes were stimulated with bacterial lipopolysaccharide and formalin-treated bacteria Escherichia coli and group B streptococci (GBS) to secrete TNF-alpha and IL-1beta, measured by ELISA.

Inflammatory processes in preterm and term parturition.

A role for the pro-inflammatory cytokines interleukin (IL)-1beta, IL-6, IL-8 and tumor necrosis factor alpha (TNF-alpha) is evident in term and preterm delivery, and this is independent of the presence of infection. All uterine tissues progress through a staged transformation near the end of pregnancy that leads from relative uterine quiescence and maintenance of pregnancy to the activation of the uterus that prepares it for the work of labour and production of stimulatory molecules that trigger the onset of labour and delivery. The uterus is activated by pro-inflammatory cytokines through stimulation of the expression and production of uterine activation proteins (UAPs).

Keratinocyte conditioned medium abrogates the modulatory effects of IGF-1 and TGF-beta1 on collagenase expression in dermal fibroblasts.

Overexpression of wound healing-promoting factors such as transforming growth factor-1 (TGF-beta1) and insulin-like growth factor-1 (IGF-1) during the healing process has been implicated in the development of dermal fibrosis in patients following thermal injury, surgical incision, and deep trauma. However, the mechanism through which the expression of these two fibrogenic factors is slowed down and/or abrogated in the late stages of the healing process is not known. Here, we hypothesize that keratinocyte-releasable factors counteract the fibrogenic role of both IGF-1 and TGF-beta1 in fibroblasts.

Transforming growth factor-beta induces differentiation of the labyrinthine trophoblast stem cell line SM10.

The mammalian placenta consists of different trophoblast cell types that assist in the variety of functions required for the maintenance of pregnancy. In rodents, labyrinthine trophoblasts of the placenta are especially important, because they are capable of differentiating into fused labyrinthine cells, which form the feto-maternal exchange surface. Even though the molecular signals triggering labyrinthine trophoblast differentiation are poorly understood, transforming growth factor-beta (TGF-beta) has been shown to be present in the placental environment and alter trophoblast development.

Proinflammatory cytokines inhibit human placental 11beta-hydroxysteroid dehydrogenase type 2 activity through Ca2+ and cAMP pathways.

Excessive fetal exposure to glucocorticoids has been implicated in the etiology of adult metabolic and cardiovascular disease. Placental 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2) may protect the fetus from excessive glucocorticoid exposure. Maternal stress may be accompanied by elevated levels of cortisol and increased proinflammatory cytokines [interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha (TNF-alpha)].

Enhanced monocyte binding to human cytomegalovirus-infected syncytiotrophoblast results in increased apoptosis via the release of tumour necrosis factor alpha.

We have shown that monocytes bound to intercellular adhesion molecules (ICAM-1) on syncytialized placental trophoblasts (ST) induce trophoblast apoptosis, and that ST infection by human cytomegalovirus (HCMV) up-regulates ICAM-1. We hypothesize that the focal loss of trophoblast seen in HCMV-infected placenta is mediated by increased adherence of monocytes at sites of infection. We find that ST cultures (differentiated from primary cytotrophoblasts) increase monocyte binding when infected with HCMV.

Epidermal growth factor stimulation of trophoblast differentiation requires MAPK11/14 (p38 MAP kinase) activation.

Cultured human term villous cytotrophoblasts (CT) have been reported to be nonproliferating but differentiate when exposed to epidermal growth factor (EGF). Here we show that CT differentiate into chorionic gonadotropin (beta-hCG/CGB)-expressing cells when cultured with medium alone. The addition of EGF decreases CGB secretion and prolongs production for up to 13 days.

Sphingosine-1-phosphate inhibition of placental trophoblast differentiation through a G(i)-coupled receptor response.

The failure of placental trophoblasts to differentiate properly is thought to play an important role in the cause of pregnancy disorders such as preeclampsia. We looked at the effects of the bioactive lipid sphingosine-1-phosphate (S1P) on the differentiation of primary human cytotrophoblasts (CTs) into syncytiotrophoblasts (STs) in culture. We found that S1P inhibited CT differentiation measured by human chorionic gonadotropin (hCG) secretion and the expression of placental alkaline phosphatase but had no effect on their fusion into multinucleated syncytialized cells.

PL74, a novel member of the transforming growth factor-beta superfamily, is overexpressed in preeclampsia and causes apoptosis in trophoblast cells.

PL74, a novel member of the TGFbeta superfamily that has highest expression in placenta, is a multifunctional peptide that can induce differentiation, inhibit inflammatory stimulation of TNFalpha, and execute apoptosis after p53 overexpression and cytotoxic injury. To study its expression and function in placenta and preeclampsia, we first determined mRNA expression in nine normal and 10 preeclamptic placentas. PL74 mRNA was overexpressed by 57.

The effects of preeclampsia and oxygen environment on endothelial release of matrix metalloproteinase-2.

Background: There is evidence of altered vascular endothelial function in women with preeclampsia as well as in the endothelial cells from umbilical vessels of preeclamptic pregnancies. Matrix metalloproteinase (MMP)-2 is elevated in the plasma of preeclamptic women and is a mediator of vascular reactivity; however, whether MMP-2 release is altered in preeclamptic endothelial cells is unknown. We hypothesize that MMP-2 release is enhanced in endothelial cells from preeclamptic compared with uncomplicated pregnancies and that this phenomenon may be mediated by an oxygen-dependent mechanism.

A proprietary extract from North American ginseng (Panax quinquefolium) enhances IL-2 and IFN-gamma productions in murine spleen cells induced by Con-A.

A patented aqueous extract from North American ginseng (Panax quinquefolium), containing mainly oligosaccharides and polysaccharides, is commercially available over the counter as COLD-FX (CVT-E002). This proprietary extract is used for the treatment of upper respiratory tract infections. Its in vitro stimulating effects on the immunoglobulin production by B lymphocytes and on natural immune responses by peritoneal exudates macrophages have been previously reported.

Adrenomedullin is decreased in preeclampsia because of failed response to epidermal growth factor and impaired syncytialization.

To explore the mechanisms of adrenomedullin (ADM) regulation in normal and preeclamptic (PE) states, we determined placental production of ADM and ADM regulation by cytokines. Isolated, purified cytotrophoblast cultures from normal (n=8) and PE (n=10) placentas were cultured for 3 days in the absence or presence of 10 ng/mL epidermal growth factor (EGF), 1 ng/mL transforming growth factor (TGF)-beta1, 10 ng/mL tumor necrosis factor (TNF)-alpha, or 100 U/mL interferon (IFN)-gamma. Cells were also cultured for 3 days in 10% fetal bovine serum for determination of syncytial formation by desmoplakin staining.

Infection of placental trophoblasts by Toxoplasma gondii.

How the intracellular parasite Toxoplasma gondii causes placental inflammation and infects the fetus is unknown. By use of a culture model of primary human trophoblasts, we examined the consequences of infection by a virulent strain of T. gondii.

Human cytomegalovirus-caused damage to placental trophoblasts mediated by immediate-early gene-induced tumor necrosis factor-alpha.

Infection of the fetal epithelium (trophoblast) lining the villous placenta by human cytomegalovirus (HCMV) accompanies placental inflammations and fetal intrauterine growth restriction. However, the consequences of infection on the villous trophoblast have not been explored. We show that HCMV infection of primary immature (cytotrophoblast-like) or mature (syncytiotrophoblast-like) cultures results in loss of half of the cells within 24 hours of virus challenge.

Trophoblasts are productively infected by CD4-independent isolate of HIV type 1.

Evidence for HIV-1 infection of trophoblasts is discordant. Utilizing highly purified full-term trophoblasts, we demonstrate that full-term trophoblasts express CXCR4 but are negative for CCR5 and CD4 cell surface proteins. Full-term trophoblasts were refractory to infection by HIV-1 IIIB and primary isolates of HIV-1.