Background: Preeclampsia is one of the leading causes of maternal mortality worldwide and is strongly associated with long-term morbidity in mothers and newborns. Referred to as one of the deep placentation disorders, insufficient remodeling of the spiral arteries during the first trimester remains a major cause of placental dysfunction. Persisting pulsatile uterine blood flow causes abnormal ischemia/reoxygenation phenomenon in the placenta and stabilizes the HIF-2α (hypoxia-inducible factor-2α) in the cytotrophoblasts.
View Article and Find Full Text PDFThe placenta is a multifaceted organ, fulfilling critical functions for the fetus and the mother. Therefore, it is a critical regulator of the pregnancy, and its dysfunction leads to diseases, including fetal growth restriction and preeclampsia. Studying the placenta is a difficult task since its existence is transient, and its structure is specific to our species.
View Article and Find Full Text PDFDespite occasional reports of vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during pregnancy, the question of placental infection and its consequences for the newborn remain unanswered. Herein, we analyzed the placentas of 31 coronavirus disease 2019-positive mothers by reverse transcriptase PCR, immunohistochemistry, and in situ hybridization. Only one case of placental infection was detected, which was associated with intrauterine demise of the fetus.
View Article and Find Full Text PDFInsufficient remodeling of uterine arteries causes pregnancy-related diseases, including fetal growth restriction and preeclampsia. In these situations, reduced maternal blood flow in the placenta is thought to be responsible for the persistence of a low oxygen environment throughout pregnancy. We hypothesized that chronic activation of transcription factors hypoxia-inducible factors (HIFs) actively participates in placental underdevelopment, which impairs fetal growth.
View Article and Find Full Text PDFVascular endothelial growth factor A (VEGF-A) is one of the main growth factors involved in placental vasculogenesis and angiogenesis, but its placental expression is still ambiguous. During in vitro cultures of primary term cytotrophoblasts, VEGF could not be detected in the supernatants by enzyme-linked immunosorbent assays (ELISA). One hypothesis is that VEGF is immediately and completely bound to its soluble receptor after secretion, and cannot be recognized by the antibodies used in the commercial ELISA kits.
View Article and Find Full Text PDFIntroduction Cancers during pregnancy can be treated with chemotherapy after the first trimester but the treatment is associated with smaller placentas and an increased risk of stillbirth, fetal growth retardation and preterm delivery. We decided to assess the effect of several chemotherapeutic agents on placental development by using in vitro culture of human term cytotrophoblasts. Methods Cytotrophoblasts isolated from term placentas were cultured for 48 h and treated for 24 h with epirubicin, docetaxel, vinblastine, methotrexate, tamoxifen, 4-hydroxytamoxifen, and endoxifen.
View Article and Find Full Text PDFDuring the first trimester of pregnancy, placenta formation probably occurs in a low-oxygen environment necessary to protect cytotrophoblasts from oxidative stress and to allow proper gene regulation. Transcription factors involved in gene regulation under low oxygen tension are the hypoxia-inducible factors, mainly HIF1A, EPAS1 and their dimerization partner HIF1B. Little is known about their expression during in vitro culture of cytotrophoblasts under chronic hypoxia.
View Article and Find Full Text PDFInhibin α (Inha) gene expression is regulated, in rat granulosa cells, via a cyclic 3',5'-adenosine monophosphate (AMP)-response element (CRE) found in a region of the promoter that is homologous to the human INHA promoter. We previously found that during in vitro cytotrophoblast differentiation, human INHA gene expression was regulated by TFAP2A via association with an AP-2 site located upstream of this CRE. The aim of this study was to evaluate if the human INHA gene was also regulated by cAMP in trophoblasts, and to investigate the possible crosstalk between TFAP2 and cAMP signaling pathways in the regulation of INHA gene expression.
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