Abstract:Objective: To investigate the involvement of diazepam binding inhibitor (DBI) in the regulation of anabolic steroid hormone gene expression in trophoblast cells. Methods: Villous tissues, from the 6th to the 8th week of gestation, were obtained from normal pregnancy and spontaneous abortion. Immunohistochemistry was used to determine the protein expression and localization of DBI in the tissues while Western blot was used to compare the protein expression of DBI between the two groups. Immunofluorescence was used to determine the protein expression of DBI in BeWo cells. Fusion of BeWo cells was induced with forskolin, and siRNA-mediated knockdown of DBI was used to determine the effect of DBI on the expression of the anabolic hormones. The mRNA expression of hormone synthase was detected by RT-qPCR, and the proliferation ability of the BeWo cells was determined by the EdU kit. Results: The expression of DBI in the spontaneous abortion villous tissues was lower than that in the normal group. Forskolin treatment induced the expression of DBI, while DBI knockdown inhibited the expression of P450scc, HSD3β1 and CYP19A1, and upregulated hormone synthetase. Also, the number of proliferating si-DBI BeWo cells was decreased. Conclusion: DBI may affect trophoblast anabolic hormone gene expression by regulating P450scc. This suggests that downregulation of DBI in the placenta might associate spontaneous abortion.
