Effect of Fas/FasL signaling pathway activation in trophoblasts on recurrent spontaneous abortion

Objective To investigate the expression of Fas/FasL in human villous trophoblast cell HTR8‐S/Vneo of patients with recurrent spontaneous abortion (RSA), and to explore the related function and molecular mechanism of Fas/FasL signaling pathway. Methods The expression levels of FasL, Fas, and E‐cadherin in the villous tissues of patients with RSA and those with artificial abortion in normal pregnancy (Normal) were detected by Western blot. CCK‐8, flow cytometry, and wound healing were used to detect cell proliferation, apoptosis, and reactive oxygen species (ROS) level, and cell migration ability. Quantitative reverse transcription PCR (RT‐qPCR) and Western blot were used to detect the expression of mRNA and protein of Notch1, FasL, Fas, E‐cadherin, PKC, Hesl, sFlt‐1, VEGF. Results Compared with normal group, the protein expression of FasL, Fas, and E‐cadherin in villous tissues of RSA group were increased. HTR‐8/SVneo cells in the H/R group had decreased proliferation and migration, increased apoptosis, and up‐regulated ROS level compared with the Control group. The activation of Fas/FasL signaling pathway promoted HTR‐8/SVneo cell injury in H/R group compared with the Fas/FasL+H/R group. Further RT‐qPCR and Western blot experiments revealed that the mRNA and protein expression of Notch1, PKC, and Hesl were decreased in H/R group compared with Control group, while the mRNA and protein expression levels of E‐cadherin, sFlt‐1, and VEGF were significantly increased. Conclusion The activation of Fas/FasL signaling pathway promotes trophoblast apoptosis induced by oxidative stress. This molecular mechanism relates to the inhibition of Notch1 signaling pathway activation, and the up‐regulation of E‐cadherin, sFlt‐1, and VEGF expression.