Todd Rosen

Maternal and perinatal risks for women over 44 - a review.

It has been widely documented that advanced maternal age constitutes a risk to both mother and child. The purpose of this review is to examine the risks posed to the pregnant mother over the age of 44 and determine if they are experienced in greater frequency than in their younger cohorts. A review of the recent literature demonstrates a significant increased incidence of cesarean section, pregnancy-induced hypertension, gestational diabetes, and perinatal mortality. There also appears to be different rates of maternal complications depending on mode of conception with assisted reproductive technology conferring a higher risk in this population. Further study is recommended in mode of conception and parity to examine the effects on maternal and fetal risks.

RelB/p52-mediated NF-κB signaling alters histone acetylation to increase the abundance of corticotropin-releasing hormone in human placenta

Glucocorticoids epigenetically induce the expression of a stress hormone gene associated with labor in human placenta cells. Epigenetics in stress and labor Pregnancy and labor are regulated by fluctuating hormone levels. Glucocorticoids stimulate production of the stress-responsive corticotropin-releasing hormone (CRH) in the placenta as the fetus nears full term. Using cultured primary trophoblasts isolated from midtrimester and full-term placenta, Di Stefano et al. found that glucocorticoids promote the expression of CRH by stimulating dynamic histone acetylation mediated by the binding of a complex containing the transcription factor nuclear factor κB (NF-κB), a histone lysine acetyltransferase, and a histone deacetylase to the CRH promoter. The findings reveal an epigenetic mechanism regulating the duration of pregnancy. Corticotropin-releasing hormone (CRH) produced in the placenta may be part of a clock that regulates the length of human gestation. Maternal plasma CRH abundance exponentially increases as pregnancy advances. Glucocorticoid stimulates CRH expression in full-term human placenta by promoting noncanonical (RelB/p52 heterodimer-mediated) nuclear factor κB (NF-κB) pathway activity. Using dexamethasone to mimic glucocorticoid exposure, we found that an epigenetic switch mediated the glucocorticoid-induced expression of CRH as gestation advances. The amount of acetylated histone H3 lysine 9 (H3K9) associated with the CRH promoter was greater in cytotrophoblasts from full-term placenta than in those from midterm placenta. Knocking down the lysine acetyltransferase CBP reduced H3K9 histone acetylation and prevented dexamethasone-induced CRH expression. Unexpectedly, knocking down the histone deacetylase HDAC1 or pharmacologically inhibiting type I and II HDACs also decreased the expression of CRH yet increased the acetylation of H3K9 and other histone regions. Both CBP and HDAC1 bound at the CRH promoter in a complex with the RelB/p52 heterodimer in a mutually dependent manner; knocking down any one factor in the complex prevented binding of the others as well as the dexamethasone-induced CRH expression. Our results suggest that glucocorticoids induce a transcription complex consisting of RelB/p52, CBP, and HDAC1 that triggers a dynamic acetylation-mediated epigenetic change to induce CRH expression in full-term human placenta.

Markers of preeclampsia and the relationship to cardiovascular disease: review of the twenty-first century literature

Objective. The objective of this article was to review the literature to identify the most promising markers of preeclampsia (PE) and the relationship to cardiovascular disease to gain a better understanding of the mechanism of PE to identify women at risk for cardiovascular disease to improve their outcomes. Methods. Forty case–control studies were assessed for relationships between different serum markers to identify PE and to identify markers that may predict women who may be at greater risk for cardiovascular sequela in later life. Results. Angiogenic, proteomic, and tumor necrosis markers were the most promising and important in the development of PE. The interplay among various growth factors, hormones, proteins, and other molecular compounds appears to be critical in the development of PE. Specific angiogenic (sVEGF, PLGF) and antiangiogenic (sFlt-1, sENG) markers and proteomic markers (fibrinogen and a-1-antichymotrypsin, SERPINA1, albumin, 1-antichymotryps) are the most promising markers of PE. Evidence of metabolic abnormalities associated with PE and common markers with cardiovascular disease include free leptin concentration which increases in normal pregnancy and is further increased in PE. Conclusions. Markers are important to help understand disease, potentially identify women at risk to improve their outcomes, design therapies to ameliorate symptoms so that pregnancy can be prolonged and neonatal outcomes improved, and provide a better understanding the link between PE and increased risk for disease later in life.

Negative Effects of Progesterone Receptor Isoform-A on Human Placental Activity of the Noncanonical NF-κB Signaling

CONTEXT Progesterone (P4)contributes to the maintenance of human pregnancy, in part by inhibiting activity of the human pro-labor genes CRH and cyclooxygenase-2 (COX-2). However, the molecular mechanisms underlying the action of P4 remain poorly defined. We have shown that in human placenta, the constitutively activated noncanonical nuclear factor (NF)-κB pathway positively regulates CRH and COX-2, which is further stimulated by glucocorticoid receptor signaling. OBJECTIVE We investigated the role of P4 receptor (PR) in the regulation of nuclear activity of v-rel avian reticuloendotheliosis viral oncogene homolog B (RelB)/NF-κB2 and, in turn, expression of placental CRH and COX-2. METHODS We used a variety of techniques including gene silencing, ectopic expression, chromatin immunoprecipitation, Western blot, quantitative RT-PCR, and immunohistochemical staining assays in human placental tissues and primary culture of human cytotrophoblast. RESULTS We identified PR isoform-A (PR-A) as the only isoform of PR produced in human placenta. PR-A levels were lower in term placenta than in midterm placenta. Depletion of PR-A by short interfering RNA derepressed inhibition of CRH and COX-2 by P4 and the synthetic progestin 17α-hydroxyprogesterone caproate. Overexpression of PR-A inhibited transcription of CRH and COX-2, which was further downregulated by treatment with P4 or 17α-hydroxyprogesterone caproate. Such an inhibition was mediated by a negative functional interaction of PR-A with the activity of RelB/NF-κB2. CONCLUSION P4 inhibits the pro-labor genes CRH and COX-2 via PR-A repression of the noncanonical NF-κB signaling in human placenta. Characterization of these pathways may identify potential drug targets for prevention of preterm birth.

STAT3 cooperates with the non-canonical NF-κB signaling to regulate pro-labor genes in the human placenta

INTRODUCTION Our recent studies have shown that constitutively activated non-canonical RelB/NF-κB2 (p52) in the human placenta positively regulates the pro-labor genes CRH and COX-2. STAT3 regulates NF-κB2 (p100) processing to active p52, and in turn, nuclear activation of RelB/p52, by directly binding to p100/p52 in a variety of cancer cells. In the current study, we tested the hypothesis that STAT3 is involved in regulation of pro-labor genes by associating with RelB/p52 heterodimers in the human placenta. METHODS We used a variety of techniques including immunohistochemical staining, gene silencing, ectopic expression, chromatin immunoprecipitation, Western blot, RT-qPCR, and immunofluorescence assays in primary culture of cytotrophoblast and placental tissues. RESULTS We found that knockdown of STAT3 led to down-regulation of both CRH and COX-2 in a dose-dependent manner. By using chromatin immunoprecipitation, we further showed that interaction of RelB with the CRH or COX-2 gene promoters decreased when STAT3 was depleted. Immunofluorescence demonstrated co-localization of STAT3 with RelB or p100/p52 in both the cytoplasm and nucleus of term cytotrophoblasts. DISCUSSION Collectively, these results suggest that STAT3 constitutes part of the RelB/p52-containing activator complex that positively regulates pro-labor genes in the human placenta.

Mono-(2-Ethylhexyl) Phthalate Promotes Pro-Labor Gene Expression in the Human Placenta

Women exposed to phthalates during pregnancy are at increased risk for delivering preterm, but the mechanism behind this relationship is unknown. Placental corticotropin-releasing hormone (CRH) and cyclooxygenase-2 (COX-2) are key mediators of parturition and are regulated by the non-canonical NF-kB (RelB/p52) signaling pathway. In this study, we demonstrate that one of the major phthalate metabolites, mono-(2-ethylhexyl)-phthalate (MEHP), increased CRH and COX-2 mRNA and protein abundance in a dose-dependent manner in primary cultures of cytotrophoblast. This was coupled with an increase in nuclear import of RelB/p52 and its association with the CRH and COX-2 promoters. Silencing of NF-kB inducing kinase, a central signaling component of the non-canonical NF-kB pathway, blocked MEHP-induced upregulation of CRH and COX-2. These results suggest a potential mechanism mediated by RelB/p52 by which phthalates could prematurely induce pro-labor gene activity and lead to preterm birth.

Discordant Embryonic Aneuploidy Testing and Prenatal Ultrasonography Prompting Androgen Insensitivity Syndrome Diagnosis

BACKGROUND: Multimodal prenatal screening for developmental pathology is increasingly common. In this case, definitive prenatal diagnosis of androgen insensitivity syndrome was diagnosed after discordant results from karyotypes determined by embryonic preimplantation genetic screening and antenatal ultrasound results. CASE: A 38-year-old woman, gravida 2 para 0010, undergoing in vitro fertilization with preimplantation genetic screening transferred one male and one female embryo. An anatomic ultrasonogram revealed two fetuses with female genitalia. Cell-free fetal DNA analyzed using noninvasive prenatal screening demonstrated Y chromosome material, and amniocentesis confirmed one 46,XX and one 46,XY fetus. Sequencing of the androgen receptor for the 46,XY fetus identified a mutation. CONCLUSION: With increased use, discordance among prenatal testing modalities such as preimplantation genetic screening, noninvasive prenatal screening, and ultrasonography will become more common requiring expert navigation to identify true pathology.

Screening a small molecule library to identify inhibitors of NF-κB inducing kinase and pro-labor genes in human placenta

The non-canonical NF-κB signaling (RelB/p52) pathway drives pro-labor genes in the human placenta, including corticotropin-releasing hormone (CRH) and cyclooxygenase-2 (COX-2), making this a potential therapeutic target to delay onset of labor. Here we sought to identify small molecule compounds from a pre-existing chemical library of orally active drugs that can inhibit this NF-κB signaling, and in turn, human placental CRH and COX-2 production. We used a cell-based assay coupled with a dual-luciferase reporter system to perform an in vitro screening of a small molecule library of 1,120 compounds for inhibition of the non-canonical NF-κB pathway. Cell toxicity studies and drug efflux transport MRP1 assays were used to further characterize the lead compounds. We have found that 14 drugs have selective inhibitory activity against lymphotoxin beta complex-induced activation of RelB/p52 in HEK293T cells, several of which also inhibited expression of CRH and COX-2 in human term trophoblast. We identified sulfapyridine and propranolol with activity against CRH and COX-2 that deserve further study. These drugs could serve as the basis for development of orally active drugs to affect length of gestation, first in an animal model, and then in clinical trials to prevent preterm birth during human pregnancy.

Trends in invasive prenatal diagnostic testing at a single institution

As diagnostic methodologies evolve, we sought to determine whether invasive testing rates would decline, whether there would be a shift in indications for invasive testing, and whether the diagnostic yield would increase.

Science Signaling Podcast: 25 August 2015

A glucocorticoid-mediated epigenetic switch promotes placental production of a stress hormone associated with labor. This Podcast features an interview with Todd Rosen and Bingbing Wang, authors of a Research Article that appears in the 25 August 2015 issue of Science Signaling, about epigenetic changes in the placenta that are induced by glucocorticoids and associated with labor. Hormones control all stages of female reproduction, including the length of gestation and the timing of labor. Corticotropin-releasing hormone (CRH) is produced by the hypothalamus in response to stress, but it is also produced by the placenta during pregnancy. Near the end of gestation, the fetus produces the glucocorticoid cortisol, which stimulates the placenta to increase CRH production. Di Stefano et al. found that glucocorticoids stimulated the expression of CRH in placental cells by promoting dynamic histone acetylation and deacetylation at the CRH promoter through a mechanism that was dependent on the transcription factor NF-κB. These findings identify an epigenetic switch that controls the duration of gestation and the timing of labor and suggest a mechanism by which placental stress induces labor. Listen to Podcast