GDF-8 stimulates trophoblast cell invasion by inducing ALK5-SMAD2/3-mediated MMP2 expression

Matrix metalloproteinases (MMPs) play a pivotal role in the regulation of cell invasion. Placental trophoblast cell invasion is a precisely regulated event. Dysregulation of MMPs has been linked to various placental diseases. Growth differentiation factor-8 (GDF-8), also known as myostatin, is a member of the transforming growth factor-beta (TGF-β) superfamily. GDF-8 and its putative receptors are expressed in human extravillous cytotrophoblast cells (EVTs). Although the pro-invasive effect of GDF-8 in human EVT cells has been recently reported, the underlying molecular mechanism remains largely unknown. In this study, we investigate the effects of GDF-8 on the expression of the two most important MMPs, MMP2 and MMP9, in the HTR-8/SVneo human EVT cell line. Our results show that GDF-8 significantly upregulates the expression of MMP2. The expression of MMP9 is not affected by GDF-8. Using a siRNA-mediated knockdown approach, we reveal that the stimulatory effect of GDF-8 on MMP2 expression is mediated by the ALK5-SMAD2/3 signaling pathway. Additionally, the knockdown of MMP2 attenuates the GDF-8-induced cell invasiveness. These findings deepen our understanding of the biological roles of GDF-8 in the regulation of human trophoblast cell invasion.

PTH-rP and PTH-R1 Expression in Placentas from Pregnancies Complicated by Gestational Diabetes: New Insights into the Pathophysiology of Hyperglycemia in Pregnancy

Background: this study investigated the expression of parathyroid hormone-related protein (PTH-rP) and PTH/PTH-rP receptor PTH-R1 in placentas from women with gestational DM (GDM), and the relationship between PTH-R1 and PTH-rP expression and pregnancy characteristics. Methods: we prospectively enrolled 78 pregnant women with GDM, and immunochemistry for PTH-rP and PTH-R1 was performed on placentas. Patients were grouped according to the positivity of PTH-R1 or PTH-rP expression, and pregnancy characteristics were compared between the two groups. Results: PTH-rP and PTH-R1 expression were highest in the extravillous cytotrophoblast and in the decidua. In extravillous cytotrophoblast, PTH-rP expression was higher in women with abnormal at fasting glycemia compared to women with abnormal 60′ or 120′ glycemia (25/25, 50% vs. 6/28, 21.4%, χ2 = 6.12, p = 0.01), and PTH-R1 expression was higher in women with abnormal oral glucose tolerance test (OGTT) at fasting glycemia compared to women with abnormal 60′ or 120′ glycemia (37/50, 74% vs. 15/28, 53.6%, χ2 = 3.37, p = 0.06). In syncytiotrophoblast, PTH-rP-positive placentas were characterized by higher incidence of 1 min Apgar score < 7 (2/9, 22.2% vs. 2/69, 2.9%, χ2 = 6.11, p = 0.01) and maternal obesity (4/9, 44.4% vs. 11/69, 16.7%, χ2 = 3.81, p = 0.05). Conclusion: placental PTH-rP and PTH-R1 expression is dependent on the type of maternal hyperglycemia, and it is associated with adverse pregnancy outcomes.

Histochemical Evaluation of the Processes of Protein Oxidative Modification in the Extravillous Cytotrophoblast of the Utero-Placental Bed during Iron-Deficiency Anemia in Pregnancy

Utero-placental bed is the cumulation of gestationally altered endometrium at the place of ovum attachment to the uterine wall. The key mechanism of this process is the cytotrophoblastic invasion. During iron deficiency anemia, an increase in the specific volume of the extravascular invasive trophoblast is taking place. Concern for the protein oxidative modification in iron deficiency anemia is due to the fact that in conditions of hypoxia, free radical processes in the blood and tissues are enhanced, and iron deficiency is additionally able to modify this problem. The purpose of the study was to establish the histochemical features of the processes of protein oxidative modification in the fractions of extravillous cytotrophoblast of the utero-placental bed depending on the degree of iron deficiency anemia in pregnant women. Material and methods. Quantitative characteristics of protein oxidative modification in the extravillous trophoblast of the utero-placental bed of pregnant women with iron deficiency anemia by means of the histochemical method using reactions with Bromophenol Blue on “acidic” and “basic” proteins according to Mikel Calvo method and computer microdensitometry. We studied 74 biopsies of the utero-placental bed of pregnant women with iron deficiency anemia of I, II and III degrees. The term of gestation was 37-40 weeks. Results and discussion. During physiological pregnancy, the ratio between "acidic" and "basic" proteins in trophoblast cells, even normally, is characterized by a predominance of "acidic" proteins, and evenly in both intravascular and extravascular fractions of cytotrophoblast. Intensification of processes of protein oxidative modification in the cytotrophoblast of the utero-placental bed during iron deficiency anemia of I-II degrees can be assessed as moderate, with an increase in the cells of the endothelium-replacing fraction of cytotrophoblast compared with the interstitial. In conditions of anemia of III degree, a significant predominance of "acidic" proteins in the intravascular cytotrophoblast was noted. Conclusion. During the physiological pregnancy, the intensity of protein oxidative modification was equal in all fractions of the extravillous cytotrophoblast in the utero-placental bed. In the case of gestation with iron deficiency anemia, significant intensification of the protein oxidative modification in the extravillous cytotrophoblast correlated with the severity of anemia. Background iron deficiency anemia significantly affected the processes of protein oxidative modification in the endothelium-replacing cytotrophoblast

Method of immunohistochemical identification of extravillous cytotrophoblast in the structures of utero-placental bed and myometrium

In this article, we discover and demonstrate the way of immunohistochemical identification of extravillous cytotrophoblast in the structures of the uteroplacental area and myometrium, which can be used to study the uteroplacental form of placental insufficiency, in the morphogenesis of which the key reason is a violation of the gestational changes of the spiral arteries of the uterus.