Biosynthesis and Metabolism of Different Hormones in the Fetal and Placental Compartments

Pasqualini, Jörge R.; Kincl, Fred A.

doi:10.1016/b978-0-08-019708-1.50006-4

Cited by 7 publications

(3 citation statements)

References 585 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…DHEAS is then hydroxylated in the fetal liver by the 16␣-hydroxylase enzyme (P450 3A7) to form 16␣-hydroxydehydroepiandrosterone sulfate (16-OH-DHEAS). In the placenta, the sulfate group of 16-OH-DHEAS is cleaved by the steroid sulfatase enzyme, forming the unconjugated steroid, 16␣-hydroxydehydroepiandrosterone (16-OH-DHEA), which is then converted to estriol in a series of steps that involves the 3␤-hydroxysteroid dehydro- genase type 1, aromatase and 17␤-hydroxysteroid dehydrogenase type 2 enzymes (7). From the second trimester, 90% of estriol production is accounted for by DHEAS derived from the fetal adrenal glands.…”

Section: Fetoplacental Synthesis Of Estriol During Pregnancymentioning

confidence: 99%

Congenital Hypopituitarism as a Cause of Undetectable Estriol Levels in the Maternal Triple-Marker Screen

Marshall

Ugrasbul

Manginello

et al. 2003

The Journal of Clinical Endocrinology & Metabolism

View full text Add to dashboard Cite

We are reporting a child with congenital panhypopituitarism, in whom deficient fetal steroidogenesis was suspected prenatally because of undetectable estriol levels measured in the maternal triple-marker screen. No fetal abnormalities were detected by ultrasonography. Amniocentesis demonstrated a normal 46,XX karyotype. Measurement of maternal urinary steroids failed to show elevation in the excretion of the major precursor for estriol, 16 alpha-hydroxydehydroepiandrosterone, indicating that the fetus did not have steroid sulfatase deficiency (placental sulfatase deficiency), the most common genetic cause of extremely low estriol. The steroid analysis excluded other rare single gene defects, including aromatase deficiency and 17 alpha-hydroxylase deficiency. We therefore suspected that the cause of low estriol in this fetus was adrenal insufficiency. Postnatal evaluation was consistent with panhypopituitarism, characterized by deficiency of all anterior pituitary hormones. Because this screen is now offered to more than half the pregnant women in the United States, reports of low estriol levels have become increasingly common. Therefore, it is essential that physicians be familiar with the various etiologies, perform the appropriate antenatal evaluation to determine the specific cause, and closely monitor both mother and child ante- and postnatally.

show abstract

Section: Fetoplacental Synthesis Of Estriol During Pregnancymentioning

confidence: 99%

Congenital Hypopituitarism as a Cause of Undetectable Estriol Levels in the Maternal Triple-Marker Screen

Marshall

Ugrasbul

Manginello

et al. 2003

The Journal of Clinical Endocrinology & Metabolism

View full text Add to dashboard Cite

show abstract

“…During early gestation, the placenta mediates the implantation of the embryo in the uterus and produces hormones that prevent the end of the ovarian cycle. The luteinizing hormone and the human chorionic gonadotrophin have a stimulating action on estrogen and progesterone synthesis by the placenta (Pasqualini and Kincl, 1985). After implantation, the placenta regulates the supply of nutrients and oxygen to the fetus.…”

Section: Physiological Function Of the Human Placental Barriermentioning

confidence: 99%

The Role of the Placenta in Fetal Exposure to Xenobiotics: Importance of Membrane Transporters and Human Models for Transfer Studies

Prouillac

Lecoeur²

2010

Drug Metab Dispos

176

127

View full text Add to dashboard Cite

ABSTRACT:The placenta is a key organ in fetal growth and development because it controls maternal-to-fetal exchanges of nutrients and hormones. It also interferes with drug delivery to the fetus by expressing active membrane transporters and xenobiotic metabolism enzymes. Developing strategies to understand the role of the placenta in drug delivery is a challenge in toxicology. Despite common physiological functions, the placentas of different species are heterogeneous in their morphology and in their expression of membrane transporters and metabolizing proteins. These characteristics raise the difficulty of obtaining a good representative model of human placental transfer. To date, different in vitro, in vivo, and ex vivo tools have been used to elucidate transport and metabolism processes in the human placenta. This study recapitulates the typical features of human placenta and then presents the placental enzymes of xenobiotic metabolism, ATP-binding cassette transporters, solute carrier transporters, and their role in fetal exposure to xenobiotics. The study also compares the characteristics of different models of human placenta, in terms of membrane localization of transporters, and the expression of xenobiotic metabolism enzymes. The use of these models for toxicological studies, in particular xenobiotic transfer, is described, and the advantages and limits of each model are summarized.

show abstract

“…Az ösztrogénhormonok és a terhesség kapcsolatát feltáró kísérleteketamelyek többek között a fetomaternoplacentaris egység létezésének igazolásához vezettek -a múlt század 1950-60-as éveiben végezték. Ebben az időszakban számos ösztrogénmetabolit, illetve metabolikus útvonal is azonosításra került[2]. Említésre méltó Diczfalusy Egon, aki a téma korai úttörőjeként számos eredménnyel -például az ösztrogének 15α-hidroxilációs metabolikus útvonalának feltérképezésével terhességben -járult hozzá az ismeretek bővüléséhez[3].…”

unclassified

Az ösztrogénmetabolizmus várandósság alatt

et al. 2019

View full text Add to dashboard Cite

The extensive metabolism of estrogen hormones, where oxidized forms, structural isomers and conjugated products appear in many tissues locally as well as in systemic circulation, is believed to be associated with a number of diseases. Targeted estrogen metabolomic studies have been largely associated with postmenopausal, malignant advert immune conditions. Although the role of estriol in maintaining pregnancy and the biological activity of estrogen metabolites is known, a relatively small number of publications have addressed the formation and transformation of these compounds during pregnancy. The aim of this study is to present in detail the formation and progression of estrogen metabolites during pregnancy and to summarize the knowledge of their role in undesirable processes occurring during gestation. Orv Hetil. 2019; 160(26): 1007–1014.

show abstract

Biosynthesis and Metabolism of Different Hormones in the Fetal and Placental Compartments

Cited by 7 publications

References 585 publications

Congenital Hypopituitarism as a Cause of Undetectable Estriol Levels in the Maternal Triple-Marker Screen

Congenital Hypopituitarism as a Cause of Undetectable Estriol Levels in the Maternal Triple-Marker Screen

The Role of the Placenta in Fetal Exposure to Xenobiotics: Importance of Membrane Transporters and Human Models for Transfer Studies

Az ösztrogénmetabolizmus várandósság alatt

Contact Info

Product

Resources

About