Expression and regulation of 11β-hydroxysteroid dehydrogenase type 1 in first trimester human decidua cells: Implication in preeclampsia

11β-hydroxysteroid dehydrogenases and biomarkers in fetal development

It is known that basal glucocorticoid levels in utero are essential for regulating fetal development and maturation, and determine the fate of later life. Recently, more and more studies suggest that adverse prenatal environments may cause abnormal maternal glucocorticoid levels in utero. 11β-hydroxysteroid dehydrogenases (11β-HSDs) are widely distributed in the target organs of glucocorticoids (GCs) and mineralocorticoids. 11β-HSDs is involved in fetal physiological and pathological development by activating or inactivating GCs. Prenatal adverse environments (including exogenous and maternal environments) can affect the expression and activity of 11β-HSDs in the placenta and fetus via multiple pathways. It induces abnormal local glucocorticoid levels in fetal multiple tissues, fetal developmental programming and homeostasis changes, and the susceptibility to various diseases after birth. We also discuss the interventions of 11β-HSDs inhibitors on fetal developmental programming and susceptibility to multiple diseases. Finally, we propose that 11β-HSD2 can be used as a molecular target for fetal developmental toxicity, while 11β-HSD1 can be regarded as an intervention target to prevent fetal-originated diseases. This review will provide a theoretical basis for the early prevention and treatment of fetal-originated diseases.

Cadmium down-regulates 11β-HSD2 expression and elevates active glucocorticoid level via PERK/p-eIF2α pathway in placental trophoblasts

Fetal overexposure to active glucocorticoid (GC) is the major cause for fetal growth restriction (FGR). This study investigated the influences of cadmium (Cd) exposure on active GC and its mechanism in placental trophoblasts. Pregnant mice were exposed to CdCl₂ (4.5 mg/kg, i.p.). Human JEG-3 cells were treated with CdCl₂ (0-20 μM). Prenatal Cd exposure significantly increased active GC level in amniotic fluid and placenta. Similarly, Cd treatment also elevated active GC level in medium. Expectedly, the expression of 11β-HSD2 protein was markedly downregulated in Cd-exposed placental trophoblasts. We further found that Cd activated the PERK/p-eIF2α signaling pathway in placental trophoblasts. Mechanistically, PERK siRNA pretreatment completely blocked PERK/p-eIF2α signaling, and thereby restoring Cd-downregulated 11β-HSD2 protein expression in human placental trophoblasts. We further found that N-acetylcysteine, a well-known antioxidant, obviously reversed Cd-downregulated 11β-HSD2 protein expression by inhibiting p-PERK/p-eIF2α signaling in placental trophoblasts. Overall, our data suggest that Cd activates the PERK/p-eIF2α signaling, down-regulates the protein expression of 11β-HSD2, and thereby elevating active GC level in placental trophoblast.

Cortisol metabolism in pregnancies with small for gestational age neonates

Small for gestational age (SGA) newborns are often born from hypertensive pregnancies. This study aimed to compare the systemic metabolism of cortisol (F) in pregnancies with SGA and appropriate for gestational age (AGA) infants, considering both the normotensive (NT) and hypertensive patients. We hypothesized that the disturbances in systemic metabolism of F in pre-eclampsia (PE) might be attributed not to hypertension only, but to SGA. The study included 117 pregnants in the third trimester, divided into groups: NT pregnancy and SGA neonate (SGA-NT); NT pregnancy and AGA neonate (AGA-NT; controls), and respective groups with PE: SGA-PE and AGA-PE. We assessed the glucocorticoid balance with the function of enzymes involved in systemic metabolism of F: 11β-hydroxysteroid dehydrogenase type 1 and 2 (11β-HSD1 and 11β-HSD2), 5α- and 5β-reductase. The enzymes' functions were estimated with the levels of F, cortisone (E), and their metabolites in plasma or urine, which we measured with HPLC-FLD and HPLC-MS/MS. The plasma F/E and urinary free F/E (UFF/UFE) ratios correlated significantly only in patients with the normal function of 5α- and 5β-reductase. The increased function of 11β-HSD2 was noted in all pre-eclamptic pregnancies. Increased function of 5α- and 5β-reductase was specific only for SGA-PE pregnancies, and the function of 5α-reductase was dependent on fetal sex. The SGA-NT pregnancies with male fetuses trended towards the higher function of renal 11β-HSD2 and 5β-reductase; SGA-NT pregnancies with female fetuses lacked any systemic glucocorticoid imbalance. In conclusion, systemic metabolism of F is the most intensive in pre-eclamptic pregnancies complicated by SGA with female fetuses. Our study supports the hypothesis about the different origins of PE and idiopathic intrauterine growth restriction and suggests the sex-specific mechanisms responsible for fetal growth restriction.

Increased cortisol metabolism in women with pregnancy-related hypertension

PURPOSE

The diminished function of 11β-hydroxysteroid dehydrogenase 2 (11β-HSD2) was found in placentae from preeclamptic pregnancies. Here, we examine the overall maternal glucocorticoid balance in pregnancy-related hypertension. We aim to answer the question if the functions of primary enzymes involved in cortisol metabolism: 11β-HSD1 and 11β-HSD2 and 5-reductases (both 5α- and 5β) are altered in the course of hypertensive pregnancy.

METHODS

We determined plasma and urinary cortisol and cortisone as well as their urinary tetrahydro- and allo-tetrahydrometabolites, both in free and conjugated forms in samples obtained from 181 Polish women in the third trimester of pregnancy. We compared steroid profiles in women with preeclampsia (PE), gestational hypertension (GH), chronic hypertension (CH) and in normotensives (controls).

RESULTS

We found significant differences in glucocorticoid balance in pregnancy-related hypertension. Plasma cortisol to cortisone was significantly lower in PE than in controls (3.00 vs. 4.79; p < 0.001). Increased function of renal 11β-HSD2 in PE and GH was manifested by significantly lower urinary free cortisol to cortisone ratio (0.169 and 0.206 vs. 0.277 in controls; p < 0.005). Markedly enhanced metabolism of cortisol was observed in pregnancy-related hypertension, with no significant alterations in CH, and the changes were more clearly expressed in PE than in GH.

CONCLUSIONS

The glucocorticoid balance in PE and GH is shifted towards decreasing cortisol concentration either due to intensified conversion to cortisone or enhanced production of tetrahydro and allo-tetrahydrometabolites.

hCG: Biological Functions and Clinical Applications

Human chorionic gonadotropin (hCG) is produced primarily by differentiated syncytiotrophoblasts, and represents a key embryonic signal that is essential for the maintenance of pregnancy. hCG can activate various signaling cascades including mothers against decapentaplegic homolog 2 (Smad2), protein kinase C (PKC), and/or protein kinase A (PKA) in several cells types by binding to luteinizing hormone/chorionic gonadotropin receptor (LHCGR) or potentially by direct/indirect interaction with transforming growth factor beta receptor (TGFβR). The molecule displays specialized roles in promoting angiogenesis in the uterine endothelium, maintaining myometrial quiescence, as well as fostering immunomodulation at the maternal-fetal interface. It is a member of the glycoprotein hormone family that includes luteinizing hormone (LH), thyroid-stimulating hormone (TSH), and follicle-stimulating hormone (FSH). The α-subunit of hCG displays homologies with TSH, LH, and FSH, whereas the β subunit is 80–85% homologous to LH. The hCG molecule is produced by a variety of organs, exists in various forms, exerts vital biological functions, and has various clinical roles ranging from diagnosis and monitoring of pregnancy and pregnancy-related disorders to cancer surveillance. This review presents a detailed examination of hCG and its various clinical applications.

Human Parturition: Nothing More Than a Delayed Menstruation

Humans are one of the few mammalian viviparous species in which pregnancy is extended beyond the luteal phase, the phase during which progesterone is synthesized by the maternal ovary. Instead, it is the fetal placenta that produces progesterone throughout the latter 2 trimesters of human pregnancy. The placenta is developmentally crucial for reproductive success and is the most conspicuous anatomical novelty of placental mammals. However, before it can exert its dual functions as both an endocrine organ and an organ capable of facilitating gas and nutrient exchange, enormous changes must take place within the uterus to not only tolerate the presence of this hemiallogeneic tissue but to also accommodate and support placental development. The most dramatic of these changes is endometrial decidualization, the origin of which coincides in evolutionary history with invasive placentation. This article builds on the observation that the physiological changes that occur during the nonpregnant secretory phase of the uterine cycle in women are remarkably similar to that seen during pregnancy. The fundamental characteristics of human pregnancy (including endometrial decidualization followed several months later by intrauterine inflammation, uterine contractions, and discharge of the decidual lining from the uterine cavity) are present already in the nonpregnant menstrual cycle and are thus independent of the fetus. We hypothesize that many of the physiological defects that lead to complications during pregnancy and parturition are detectable already during spontaneous decidualization in the nonpregnant state and at the onset of menstruation, and can thus be determined before the onset of pregnancy.

11β-hydroxysteroid dehydrogenase type 1 and pregnancy: Role in the timing of labour onset and in myometrial contraction

Glucocorticoids play a primary role in the maturation of fetal organs and may contribute to the onset of labour. Glucocorticoid activity depends on the 11β-hydroxysteroid dehydrogenase family (11β-HSDs), catalysing the interconversion between "active" cortisol into inactive cortisone. No definitive study exists on 11β-HSD expression profile in human decidua and myometrium during pregnancy. We investigated the implications of 11β-HSD1 in the regulation of uterine activity in pregnancy, examining its role on contraction of a myocyte cell line and murine 11β-hsd1 levels in utero. Murine 11β-hsd1 mRNA and protein levels in utero progressively increased until the last day of gestation and significantly decreased at the onset of labour (P < 0.0001) (n = 3 to 5 in the various gestational days analysed). Experiments on human myometrial samples confirm the significant fall in 11β-hsd1 mRNA levels at labour, compared to end pregnancy samples (n = 5 to 8). In vitro experiments showed that human myometrial contraction is inhibited by using a non-selective inhibitor of 11β-HSD1. The present study shows the temporal localisation of 11β-HSD1 in uterus, highlighting its importance in the timing of gestation and suggesting its contribution in the myometrium contraction.