Placental Productions and Expressions of Soluble Endoglin, Soluble fms-Like Tyrosine Kinase Receptor-1, and Placental Growth Factor in Normal and Preeclamptic Pregnancies

• Published in: The journal of clinical endocrinology and metabolism 2008-01, Vol.93 (1), p.260-266
• Main Authors: Gu, Yang, Lewis, David F., Wang, Yuping
• Format: Article
• Language: English
• Subjects: Antigens, CD - biosynthesis; Biological and medical sciences; Blotting, Western; Endocrinopathies; Endoglin; Enzyme-Linked Immunosorbent Assay; Feeding. Feeding behavior; Female; Fundamental and applied biological sciences. Psychology; Glycosylation; Humans; Immunohistochemistry; Medical sciences; Original; Placenta - metabolism; Placenta Growth Factor; Pre-Eclampsia - metabolism; Pregnancy; Pregnancy Proteins - biosynthesis; Receptors, Cell Surface - biosynthesis; Trophoblasts - metabolism; Vascular Endothelial Growth Factor Receptor-1 - biosynthesis; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vertebrates: endocrinology
• ISSN: 0021-972X; 1945-7197
• DOI: 10.1210/jc.2007-1550

Context: Increased production of antiangiogenic factors soluble endoglin (sEng) and soluble fms-like tyrosine kinase receptor-1 (sFlt-1) by the placenta contributes to the pathophysiology in preeclampsia (PE). Objective: Our objective was to determine the differences in endoglin (Eng), fms-like tyrosine kinase receptor-1 (Flt-1), and placental growth factor (PlGF) expressions between normal and PE placentas and sEng, sFlt-1, and PlGF production by trophoblast cells (TC) cultured under lowered oxygen conditions. Methods: TCs isolated from normal and PE placentas were cultured under regular (5% CO2/air) and lowered (2% O2/5% CO2/93% N2) oxygen conditions. sEng, sFlt-1, and PlGF productions were determined by ELISA. Protein expressions for Eng, Flt-1, and PlGF in the placental tissues were accessed by immunohistochemical staining and Western blot analysis. Deglycosylated Eng, Flt-1, and PlGF protein expressions in placental tissues were also examined. Results: PE TCs produced significantly more sEng, sFlt-1, and PlGF compared with those from normal TCs (P < 0.05). Under lowered oxygen conditions, PE TCs, but not normal TCs, released more sEng and sFlt-1. In contrast, both normal and PE TCs released less PlGF (P < 0.05). Enhanced expressions of Eng and Flt-1, as well as glycosylated Eng and Flt-1, were observed in PE placentas. Immunoblot also revealed that TCs released glycosylated sFlt-1, but not sEng, in culture. Conclusions: PE TCs produce more sEng, sFlt-1, and PlGF than normal TCs. Lowered oxygen conditions promote sEng and sFlt-1, but reduce PlGF, productions by PE TCs. More glycosylated sEng and sFlt-1 are present in PE placentas. Trophoblasts release glycosylated sFlt-1, but unglycosylated sEng, in culture.