Pathologic abnormalities of placental structure and function in diabetes
Moshe Hod, Lois G. Jovanovic, Gian Carlo Di Renzo, Alberto de Leiva, Oded Langer in Textbook of Diabetes and Pregnancy, 2018
At term, the normal human placenta is a focal, disklike thickening of the membranous sac that is achieved by splitting the membranes into two separate sheets, the chorionic plate and the basal plate. Both sheets enclose the intervillous space as a cover and bottom. The intervillous space is perfused with maternal blood, which circulates freely and directly around the trophoblastic surface of the placental villi. The villi originate from a complex, treelike projection of the chorionic plate into the intervillous space (Figure 11.1). The villous surface is surrounded by the trophoblast and a core composed of stroma that supports the fetal vessels connected to the fetal circulation system via the chorionic plate and umbilical cord. At the placental margin, the intervillous space is obliterated as the chorionic and basal plates fuse together to form the chorion laeve.5
Clinical Implications of Anti-Phospholipid Antibodies: The Utah Experience
E. Nigel Harris, Thomas Exner, Graham R. V. Hughes, Ronald A. Asherson in Phospholipid-Binding Antibodies, 2020
This scenario is most compatible with impaired maternal circulation to the intervillous space, or so called utero-placental insufficiency (UPI). Detailed studies of the placentas taken from pregnancies complicated with aPL and fetal death have shown that the UPI is most likely due to a spiral arteriolar vasculopathy, best seen in the decidual segments of these vessels.24 Normally, the structure of these vessels is engineered in the late first- and second trimester when trophoblastic cells invade the most superficial portions of the maternal vessels to establish the utero-placental circulation.25-26 The result is that the muscular and elastic portions of the vascular wall are replaced by hyalin and fibrin in which trophoblastic cells are embedded. It is generally thought that these changes are designed to allow the utero-placental spiral arterioles to function at maximum flow and low resistance, unresponsive to maternal vasoconstrictive agents.
Maternal Fetal Circulation and Respiration
Miriam Katz, Israel Meizner, Vaclav Insler in Fetal Well-Being, 2019
Blood in the human placenta leaves normal vascular channels to circulate in a new, extravascular space which is unique for the duration of pregnancy. The intervillous space lies within the uterine cavity, and since the placenta is a flexible structure, pressure generated by myometrial contractions will influence the placental blood flow. During pregnancy blood vessels supplying the placenta progressively dilate, increasing the total uterine blood flow and shunting blood from nonplacental to placental tissue. Spiral arterioles that supply the intervillous space loose their vessel wall, replacing it by trophoblast and thus dilate about 10 times, turning into spiral arteries. Placental blood flow at term represents approximately 90% of the total uterine blood flow (Figure 1.3).
Increased levels of serum serglycin and agrin is associated with adverse perinatal outcome in early onset preeclampsia
Published in Fetal and Pediatric Pathology, 2019
Basak Gumus Guler, Sibel Ozler
Preeclampsia is associated with increased risk of adverse pregnancy outcomes, such as fetal growth restriction (FGR), preterm delivery, and intrauterine fetal death (IUFD) [3]. It may cause cerebrovascular complications such as intracranial bleeding, eclampsia, posterior reversible encephalopathy syndrome, pulmonary edema, acute renal failure, and maternal death [4, 5]. Maternal complications, namely chronic hypertension, cardiovascular disease, metabolic disease, and renal disease may also be observed in late-term [6–8]. The factors responsible for disease pathogenesis and/or predictive of adverse fetal and maternal outcomes have not been clearly defined. The improvement in impaired clinical and laboratory parameters after labor suggests the placenta has a major role in disease pathogenesis. Human extravillous trophoblasts invade the maternal decidua and reconstruct maternal spiral arterioles during early placentation. As a result, this allows the passage of maternal blood into intervillous space to support continuous placental function. The blood in the intervillous space supplies the fetus with oxygen and nutrients at the villous trophoblastic interface [9]. The extravillous trophoblasts are the main placental structure interacting with spiral arterioles in the uterine decidua [10].
Relationship between G proteins coupled receptors and tight junctions
Published in Tissue Barriers, 2018
Lorenza González-Mariscal, Arturo Raya-Sandino, Laura González-González, Christian Hernández-Guzmán
The placenta regulates the transfer of materials between the mother and the developing fetus. One of the earliest steps of placental development is branching of the sheet of trophoblast cells. These cells are present at the outer layer of the blastocyst, and branching increases the surface of the epithelium of the chorionic villi that exchanges nutrients, gases and wastes between the fetus and the mother's blood present in the intervillous space. Wnt ligands via frizzled-5 receptor and the activation of the Wnt signaling pathway, regulate chorionic branching. Thus, the up-regulation of frizzled 5 triggered by transcription factor Gcm 1 induces the dissociation of cell junctions needed for branching initiation through the down-regulation of ZO-1, claudin-4 and claudin-7 in trophoblast cells, at the base of the chorion.152
Incorporating placental tissue in cord blood banking for stem cell transplantation
Published in Expert Review of Hematology, 2018
Luciana Teofili, Antonietta R. Silini, Maria Bianchi, Caterina Giovanna Valentini, Ornella Parolini
The human term placenta is a round-shaped, feto-maternal organ that has variable diameters (15–20 cm) and thicknesses (2–3 cm). The fetal part of the placenta is composed of the placental disk, the amniotic and chorionic membranes (often referred to as the fetal membranes), and the umbilical cord. The maternal side is comprised of the decidua, which is derived from the maternal endometrium [1]. The placental disk consists of a chorionic plate and a basal plate, which together form a base and a cover, respectively, to enclose the intervillous space, and is surrounded by the fetal membranes, which closely adhere to each other and form the amniotic sac. The amniotic membrane (AM) is a thin, avascular sheet comprised of epithelial and stromal layers [2]. The ectodermal-derived amniotic epithelium is composed of a single layer of flat, cuboidal, or columnar epithelial cells uniformly arranged on a basement membrane [1]. The amniotic epithelium also covers the umbilical cord, which is composed of one umbilical vein and two umbilical arteries embedded in a gelatinous proteoglycan-rich matrix called Wharton’s jelly (WJ). The amniotic stroma derives from mesoderm and consists of a collagen-rich acellular compact layer with widely dispersed fibroblast-like cells and rare macrophages. The chorion is the outermost membrane of the sac enclosing the fetus, and is comprised of the chorionic stromal and trophoblastic layers, which include extravil-cytotrophoblast cells [3].
Related Knowledge Centers
- Blood Transfusion
- Placenta
- Embryo
- Trophoblast
- Endometrium
- Chorionic Villi