地西泮结合抑制因子调控胎盘滋养细胞合成类固醇激素基因的表达

Diazepam binding inhibitor regulates the expression of steroid hormone synthesis genes in placental trophoblast cells

摘要:

目的： 探讨地西泮结合抑制因子（diazepam binding inhibitor，DBI）是否参与胎盘滋养细胞合成类固醇激素基因表达的调控。方法： 收集自然流产以及正常孕6~8周绒毛组织，Western blot比较2组样本DBI蛋白的表达，免疫组织化学分析DBI在绒毛组织中的表达和定位。利用siRNA分别敲低DBI表达并采用Forskolin FSK诱导BeWo滋养细胞合体化，免疫荧光检测DBI的蛋白表达、RT-qPCR检测激素合成酶的表达水平，EdU试剂盒检测细胞增殖能力。结果： 自然流产绒毛中的DBI较正常组呈现下调表达；FSK可诱导DBI及激素合成酶P450scc、HSD3β1和CYP19A1上调表达；而敲低DBI不仅可以抑制合体化进程，同时也抑制激素合成酶的表达。结论： DBI可能通过调控P450scc介导滋养细胞类固醇激素合成功能，进而参与胎盘发育。

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.