The Interaction between Endovascular Human Trophoblast and Endothelial Cells Is Regulated in vitro by Lysophosphatidic Acid.

SCOTTI, L; FRANCHI, ANA M; SORDELLI, MS; PARBORELL, F; BELTRAME, JS; CAÑUMIL, VA; RIBEIRO MARÍA LAURA

París

Congreso; Society for Reproductive Investigation; 2019

Society for Reproductive Investigation

Introduction: Spiral artery remodeling at the maternal-fetal interface is crucial for successful pregnancy and requires the interaction between first trimester trophoblast and endothelial cells of the maternal vessels. However, the precise mechanism of this dialogue has yet to be determined. Previously, we reported that lysophosphatidic acid (LPA), a bioactive lipid, promotes angiogenesis of rat implantation sites and acquisition of human first trimester trophoblast endovascular phenotype. The current study investigated whether LPA modulates in vitro trophoblast-endothelial crosstalk. Methods: HTR-8/SVneo trophoblast cell line H8 were seeded on top of Geltrex, incubated with LPA or LPA+NS-398 (selective cyclooxygenase-2 inhibitor), LPA+1400W (selective inducible nitric oxide synthase inhibitor) or LPA+IL-6 neutralizing antibody and assayed for tube formation to model the acquisition of trophoblast endovascular phenotype. Supernatants were collected and used as conditioned media (CM). To test trophoblast-endothelial crosstalk, the endothelial cell line EA.hy926 was incubated with trophoblast CM. EA.hy926 apoptosis (TUNEL assay) and migration (wound healing) were evaluated. IL-6 mRNA levels (qPCR) and MMPs activities (zymography) were determined in H8. Results: CM from LPA-induced tubulogenesis stimulated endothelial cells migration (p < 0.05) and did not modify apoptosis. However, LPA added directly to EA.hy926 did not affect endothelial cells migration compared to control-CM. Soluble factors derived from cyclooxygenase-2 and IL-6 pathways were involved in H8 - EA.hy926 interaction under LPA effect. Moreover, LPA increased IL-6 mRNA levels by cyclooxygenase-2 pathway in H8 cells (p < 0.05). Finally, MMP-2 and MMP-9 activities in H8 supernatants were triggered by LPA (p < 0.05). Conclusion: Collectively, LPA promotes trophoblast-endothelial crosstalk in vitro and induces the release of trophoblast soluble factors that stimulate endothelial cells migration without changes in apoptosis. The evidence presented here provides new insights about an active role of LPA as a lipid mediator regulating vascular adaptations at the maternal-fetal interface.