Reproductive Medicine Center, Department of Obstetrics and Gynecology, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Nanjing, Jiangsu, China.
Nanjing University Medical School, Nanjing, Jiangsu, China.
Reproduction. 2019 Mar;157(3):273-282. doi: 10.1530/REP-18-0417.
Decidualization renders the endometrium transiently receptive to an implanting blastocyst although the underlying mechanisms remain incompletely understood. The aim of this study was to determine the role of chemokine CXCL16 and its receptor CXCR6 in the decidualization during pregnancy. Here, the expression of CXCL16 was investigated in endometrial tissues, decidua and placenta in this study. Compared with endometrial tissue, protein expression of CXCL16 was significantly higher in tissues from the fertile control samples, especially in villus. Meanwhile, the primary trophoblast cells and decidual stromal cells (DSCs) secreted more CXCL16 and expressed higher CXCR6 compared to endometrial stromal cells (ESCs) in vitro. Stimulation with the inducer of decidualization (8-bromoadenosine 3',5'-cyclic with medroxyprogesterone acetate, 8-Br-cAMP plus MPA) significantly upregulated the expression of CXCL16 and CXCR6 in ESCs in vitro. After treatment with exogenous recombinant human CXCL16 (rhCXCL16) or trophoblast-secreted CXLC16, decidualised ESCs showed a significant decidual response, mainly characterised by increased prolactin (PRL) secretion. Simultaneously, PI3K/PDK1/AKT/Cyclin D1 pathway in decidualised ESCs were activated by rhCXCL16, and AKT inhibitor GS 690693 abolished the PRL secretion of ESCs that was triggered by rhCXCL16. Finally, the impaired CXCL16/CXCR6 expression could be observed at the maternal-foetal interface from patients who have experienced spontaneous abortion. This study suggests that the CXCL16/CXCR6 axis contributes to the progression of ESC decidualization by activating PI3K/PDK1/AKT/Cyclin D1 pathway. It unveils a new paradigm at the maternal-foetal interface in which CXCL16 is an initiator for the molecular crosstalk that enhances decidualization of ESCs.
蜕膜化使子宫内膜暂时能够接受着床的胚泡,但其中的潜在机制尚不完全清楚。本研究旨在确定趋化因子 CXCL16 及其受体 CXCR6 在妊娠蜕膜化中的作用。本研究检测了 CXCL16 在子宫内膜组织、蜕膜和胎盘组织中的表达。与子宫内膜组织相比,在有生育能力的对照组样本中,CXCL16 的蛋白表达显著升高,特别是在绒毛中。同时,与子宫内膜基质细胞(ESCs)相比,原代滋养层细胞和蜕膜基质细胞(DSCs)在体外分泌更多的 CXCL16,并表达更高水平的 CXCR6。体外用诱导蜕膜化的药物(8-溴环磷酸腺苷加醋酸甲羟孕酮,8-Br-cAMP 加 MPA)刺激后,ESCs 中 CXCL16 和 CXCR6 的表达显著上调。用外源性重组人 CXCL16(rhCXCL16)或滋养层细胞分泌的 CXLC16 处理后,蜕膜化的 ESCs 表现出明显的蜕膜反应,主要表现为催乳素(PRL)分泌增加。同时,rhCXCL16 激活了蜕膜化 ESCs 中的 PI3K/PDK1/AKT/Cyclin D1 通路,AKT 抑制剂 GS 690693 阻断了 rhCXCL16 触发的 ESCs 的 PRL 分泌。最后,在经历自然流产的患者的母胎界面处观察到 CXCL16/CXCR6 表达受损。本研究表明,CXCL16/CXCR6 轴通过激活 PI3K/PDK1/AKT/Cyclin D1 通路,促进 ESC 蜕膜化的进展。它揭示了母胎界面上的一个新范例,即 CXCL16 是增强 ESC 蜕膜化的分子串扰的启动子。