AUTHOR=Wang Ya-Nan , Ye Yixin , Zhou Da , Guo Ze-Wen , Xiong Zhelei , Gong Xing-Xing , Jiang Shi-Wen , Chen Haibin 

TITLE=The Role of Syncytin in Placental Angiogenesis and Fetal Growth

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2022.852561

DOI=10.3389/fcell.2022.852561

ISSN=2296-634X

ABSTRACT=<p><bold>Background:</bold> Syncytin, a retroviral envelope protein, is specifically expressed on trophoblast cells and mediates formation of the syncytiotrophoblast through fusogenic activity. Decreased expression of Syncytin was found in fetal growth restriction placentas.</p><p><bold>Results:</bold> By generating an inducible knockout of the <italic>syncytin-a</italic> gene in mice, we show a specific disruption of placental angiogenesis with abnormal formation of two syncytiotrophoblast layers. Consistent with the defects observed <italic>in vivo</italic>, conditioned medium collected from trophoblast cells, following Syncytin-1 knockdown, contains lower expression of vascular endothelial growth factor and placental growth factor, and higher levels of soluble fms-like protein kinase-1 in BeWo and HTR-8/SVneo cells which related with suppressed PI3K/Akt/mTOR pathway, and is reduced in ability to induce tube formation by HUVECs.</p><p><bold>Conclusion:</bold> Syncytin participates in angiogenesis during placental development was first identified both <italic>in vivo</italic> and <italic>in vitro</italic>. Here, we give a new sight on understanding syncytin and pathophysiology of placenta related disease such as fetal growth restriction.</p>