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Biology of Reproduction Jul 2018Placentation is a reproductive adaptation that permits fetal growth and development within the protected confines of the female reproductive tract. Through this... (Review)
Review
Placentation is a reproductive adaptation that permits fetal growth and development within the protected confines of the female reproductive tract. Through this important role, the placenta also determines postnatal health and susceptibility to disease. The hemochorial placenta is a prominent feature in primate and rodent development. This manuscript provides an overview of the basics of hemochorial placental development and function, provides perspectives on major discoveries that have shaped placental research, and thoughts on strategies for future investigation.
Topics: Adaptation, Physiological; Animals; Female; Fetal Development; Humans; Maternal-Fetal Exchange; Placenta; Placentation; Pregnancy; Reproduction
PubMed: 29481584
DOI: 10.1093/biolre/ioy049 -
International Journal of Environmental... Jun 2022Placental syndromes include pregnancy loss, fetal growth restriction, preeclampsia, preterm delivery, premature rupture of membranes, placental abruption and... (Review)
Review
Placental syndromes include pregnancy loss, fetal growth restriction, preeclampsia, preterm delivery, premature rupture of membranes, placental abruption and intrauterine fetal demise. This paper discusses the common etiopathogenesis of those syndromes and the role of angiogenic biomarkers in their development. Pregnancy implantation, placental development and maternal adaptation are complex processes in which fetal and maternal cells interact. The syncytiotrophoblast, trophoblast, uterine natural killer cells and regulatory T cells interfere and interact in all the above-mentioned processes. The proper angioneogenesis and vasculogenesis of the placenta, as well as maternal circulatory adaptation, are dependent on angiogenic factor expression. Insufficient maternal immunotolerance, dysregulation in uterine natural killer or regulatory T cell function, syncytiotrophoblast and trophoblast ischemia and hypoxia or impaired balance in angiogenic factors are all related to the occurrence of placental syndromes. Differences in the time of impairment onset and its intensity and correlation with other dysfunctions result in the development of a specific syndrome. The clinical manifestations in the form of a combination of specific symptoms determine the diagnosis. However, they are just symptoms of an underlying complex trophoblast disorder.
Topics: Female; Humans; Infant, Newborn; Perinatology; Placenta; Placentation; Pre-Eclampsia; Pregnancy; Syndrome
PubMed: 35742640
DOI: 10.3390/ijerph19127392 -
Advances in Experimental Medicine and... 2023The placenta is an intriguing organ that allows us to survive intrauterine life. This essential organ connects both mother and fetus and plays a crucial role in maternal... (Review)
Review
The placenta is an intriguing organ that allows us to survive intrauterine life. This essential organ connects both mother and fetus and plays a crucial role in maternal and fetal well-being. This chapter presents an overview of the morphological and functional aspects of human placental development. First, we describe early human placental development and the characterization of the cell types found in the human placenta. Second, the human placenta from the second trimester to the term of gestation is reviewed, focusing on the morphology and specific pathologies that affect the placenta. Finally, we focus on the placenta's primary functions, such as oxygen and nutrient transport, and their importance for placental development.
Topics: Pregnancy; Female; Humans; Placenta; Fetus; Placentation; Fetal Development
PubMed: 37466767
DOI: 10.1007/978-3-031-32554-0_1 -
Biology of Reproduction Sep 2023During pregnancy, cell senescence at the maternal-fetal interface is required for maternal well-being, placental development, and fetal growth. However, recent reports... (Review)
Review
During pregnancy, cell senescence at the maternal-fetal interface is required for maternal well-being, placental development, and fetal growth. However, recent reports have shown that aberrant cell senescence is associated with multiple pregnancy-associated abnormalities, such as preeclampsia, fetal growth restrictions, recurrent pregnancy loss, and preterm birth. Therefore, the role and impact of cell senescence during pregnancy requires further comprehension. In this review, we discuss the principal role of cell senescence at the maternal-fetal interface, emphasizing its "bright side" during decidualization, placentation, and parturition. In addition, we highlight the impact of its deregulation and how this "dark side" promotes pregnancy-associated abnormalities. Furthermore, we discuss novel and less invasive therapeutic practices associated with the modulation of cell senescence during pregnancy.
Topics: Pregnancy; Female; Infant, Newborn; Humans; Placenta; Premature Birth; Parturition; Placentation; Cellular Senescence
PubMed: 37402700
DOI: 10.1093/biolre/ioad071 -
International Journal of Molecular... Mar 2021The pathogenesis of preeclampsia begins when a fertilized egg infiltrates the decidua, resulting in implantation failure (e.g., due to extravillous trophoblast... (Review)
Review
The pathogenesis of preeclampsia begins when a fertilized egg infiltrates the decidua, resulting in implantation failure (e.g., due to extravillous trophoblast infiltration disturbance and abnormal spiral artery remodeling). Thereafter, large amounts of serum factors (e.g., soluble fms-like tyrosine kinase 1 and soluble endoglin) are released into the blood from the hypoplastic placenta, and preeclampsia characterized by multiorgan disorder caused by vascular disorders develops. Successful implantation and placentation require immune tolerance to the fertilized egg as a semi-allograft and the stimulation of extravillous trophoblast infiltration. Recently, exosomes with diameters of 50-100 nm have been recognized to be involved in cell-cell communication. Exosomes affect cell functions in autocrine and paracrine manners via their encapsulating microRNA/DNA and membrane-bound proteins. The microRNA profiles of blood exosomes have been demonstrated to be useful for the evaluation of preeclampsia pathophysiology and prediction of the disease. In addition, exosomes derived from mesenchymal stem cells have been found to have cancer-suppressing effects. These exosomes may repair the pathophysiology of preeclampsia through the suppression of extravillous trophoblast apoptosis and promotion of these cells' invasive ability. Exosomes secreted by various cells have received much recent attention and may be involved in the maintenance of pregnancy and pathogenesis of preeclampsia.
Topics: Animals; Cell Communication; Exosomes; Female; Humans; MicroRNAs; Placenta; Placentation; Pre-Eclampsia; Pregnancy; Trophoblasts
PubMed: 33806480
DOI: 10.3390/ijms22052572 -
Placenta Apr 2018
Topics: Animals; Female; Humans; Placenta; Placentation; Pregnancy
PubMed: 29398014
DOI: 10.1016/j.placenta.2018.01.004 -
Advances in Anatomy, Embryology, and... 2021It is sometimes implied that marsupials are "aplacental," on the presumption that the only mammals that have a placenta are the eponymous "placental" mammals. This...
It is sometimes implied that marsupials are "aplacental," on the presumption that the only mammals that have a placenta are the eponymous "placental" mammals. This misconception has persisted despite the interest in and descriptions of the marsupial placenta, even in Amoroso's definitive chapter. It was also said that marsupials had no maternal recognition of pregnancy and no placental hormone production. In addition, it was thought that genomic imprinting could not exist in marsupials because pregnancy was so short. We now know that none of these ideas have held true with extensive studies over the last four decades definitively showing that they are indeed mammals with a fully functional placenta, and with their own specializations.
Topics: Animals; Female; Genomic Imprinting; Mammals; Marsupialia; Placenta; Placentation; Pregnancy
PubMed: 34694477
DOI: 10.1007/978-3-030-77360-1_4 -
Reproduction (Cambridge, England) Jun 2018MicroRNAs (miRNAs) are small non-coding single-stranded RNAs that are integral to a wide range of cellular processes mainly through the regulation of translation and... (Review)
Review
MicroRNAs (miRNAs) are small non-coding single-stranded RNAs that are integral to a wide range of cellular processes mainly through the regulation of translation and mRNA stability of their target genes. The placenta is a transient organ that exists throughout gestation in mammals, facilitating nutrient and gas exchange and waste removal between the mother and the fetus. miRNAs are expressed in the placenta, and many studies have shown that miRNAs play an important role in regulating trophoblast differentiation, migration, invasion, proliferation, apoptosis, vasculogenesis/angiogenesis and cellular metabolism. In this review, we provide a brief overview of canonical and non-canonical pathways of miRNA biogenesis and mechanisms of miRNA actions. We highlight the current knowledge of the role of miRNAs in placental development. Finally, we point out several limitations of the current research and suggest future directions.
Topics: Animals; Female; Humans; MicroRNAs; Placenta; Placentation; Pregnancy
PubMed: 29615475
DOI: 10.1530/REP-17-0603 -
Placenta Sep 2018The most important function of the placenta is the exchange of nutrients and oxygen between a mother and her fetus. To establish a healthy functioning placenta,... (Review)
Review
The most important function of the placenta is the exchange of nutrients and oxygen between a mother and her fetus. To establish a healthy functioning placenta, placentation needs to occur with adequate remodelling of spiral arteries by extravillous trophoblasts. When this process is impaired, the resulting suboptimal and inadequate placenta function results in the manifestation of pregnancy complications. Impaired placenta function can cause preeclampsia and leads to fetal growth restriction due to hypoxia. Presence of hypoxia leads to oxidative stress due to an imbalance between reactive oxygen species and antioxidants, thereby causing damage to proteins, lipids and DNA. In the placenta, signs of morphological adaptation in response to hypoxia can be found. Different placental lesions like maternal or fetal vascular malperfusion or chronic villitis lead to a decreased exchange of oxygen between the mother and the fetus. Clinically, several biomarkers indicative for oxidative stress, e.g. malondialdehyde and reduced levels of free thiols are found. This review aims to give an overview of the causes and (potential) role of placental oxidative stress in the development of placental parenchymal pathology and its clinical consequences. Also, therapeutic options aiming at prevention or treatment of hypoxia of the placenta and fetus are described.
Topics: Female; Humans; Oxidative Stress; Placenta; Placenta Diseases; Placentation; Pregnancy; Reactive Oxygen Species
PubMed: 29622278
DOI: 10.1016/j.placenta.2018.03.003 -
Reproduction (Cambridge, England) Nov 2016The very apt definition of a placenta is coined by Mossman, namely apposition or fusion of the fetal membranes to the uterine mucosa for physiological exchange. As such,... (Review)
Review
The very apt definition of a placenta is coined by Mossman, namely apposition or fusion of the fetal membranes to the uterine mucosa for physiological exchange. As such, it is a specialized organ whose purpose is to provide continuing support to the developing young. By this definition, placentas have evolved within every vertebrate class other than birds. They have evolved on multiple occasions, often within quite narrow taxonomic groups. As the placenta and the maternal system associate more intimately, such that the conceptus relies extensively on maternal support, the relationship leads to increased conflict that drives adaptive changes on both sides. The story of vertebrate placentation, therefore, is one of convergent evolution at both the macromolecular and molecular levels. In this short review, we first describe the emergence of placental-like structures in nonmammalian vertebrates and then transition to mammals themselves. We close the review by discussing the mechanisms that might have favored diversity and hence evolution of the morphology and physiology of the placentas of eutherian mammals.
Topics: Animals; Biological Evolution; Female; Humans; Placenta; Placentation; Pregnancy
PubMed: 27486265
DOI: 10.1530/REP-16-0325