前列腺素/前列腺素受体经非低氧途径调控HIF-1α及其在月经发生中的作用机制

Menstruation is vital to women. Long time ago, it was thought that prostaglandin (PG) were tightly associated with the endometrial breakdown in menstruation. However, it was also thought that they were only the “vestige” in the involvement in primate and did not play an obligative role in menstruation. The obligative role of PGs in menstruation and its regulation remained unsolved. In our previous study, we had built the mouse menstrual-like model, and found that the rate-limiting enzyme of PGs—COX-2 plays an obligatory role in the endometrial breakdown and bleeding, and HIF-1αshows the similar function as COX-2, however, hypoxia does not lead to endometrial breakdown. Furthermore, COX-2 regulates the expression of HIF-1α.The downstream cytokines that COX-2 regulated are related to the vascular regulation and inflammation. From these findings, we speculated that PGs regulated HIF-1αin non-hypoxia manner to lead to endometrial breakdown by vascular permeability and inflammation in menstruation. In this application, we will investigate the role of specific PG and its receptor in menstruation, and the downstream regulation that PGs/PG receptor regulated HIF-1αto endometrial breakdown and bleeding by inhibitor interference, gene knock-down and co-immunoprecipitation technologies in mouse menstrual-like model, human endometrial primary cell and human endometrium. The results will provide the molecular markers for treatment of abnormal uterine bleeding.

月经状况对妇女健康影响巨大。长期以来，前列腺素（PG）被认为与月经发生子宫内膜的崩解出血紧密相关；但也有相反观点认为，其仅是高等灵长类动物进化的“废弃物”，与月经发生无关。PGs在月经发生中的主导作用及其下游调控机制不明。我们前期利用小鼠月经样模型发现：PGs限速合成酶COX-2对子宫内膜崩解起重要作用，HIF-1α与其作用一致，但低氧并不能导致子宫内膜崩解；COX-2调控HIF-1α的表达；COX-2下游涉及血管调节和炎症相关的细胞因子。基于前期发现，我们首次提出：PGs/PG受体经非低氧途径调控HIF-1α，通过调节血管通透性介导炎症而导致子宫内膜崩解。本项目拟利用小鼠月经样模型结合人子宫内膜原代细胞/临床标本，通过抑制剂干预、基因敲降和免疫共沉淀等手段，解析不同种类PGs及其受体在月经中的作用，以及经非低氧途径调控HIF-1α导致此生理事件的机制，这将为治疗子宫异常出血提供分子靶标。

月经状况对妇女健康影响巨大。长期以来，前列腺素（PG）被认为与月经发生子宫内膜的崩解出血紧密相关；但也有相反观点认为，其仅是高等灵长类动物进化的“废弃物”，与月经发生无关。PGs在月经发生中的主导作用及其下游调控机制不明。项目组成功建立小鼠月经样模型，并首次成功建立HESC诱导蜕膜化模拟月经发生的细胞体系；发现在崩解期子宫内膜中PGF2α和PGE的含量显著增加并在孕酮撤退的16h达到峰值，此时是子宫内膜的崩解脱落的关键期，提示PGF2α和PGE对子宫内膜的崩解脱落起重要作用；PTGFR和 PGER2蛋白在子宫内膜崩解期的子宫内膜中存在表达，且在16 h定位于蜕膜化区域外周边界，此区域是子宫内膜功能层即将从基底层剥脱的区域，而PGER2在整个崩解期虽然存在表达，但并未有区域性分布。同时，Ptgfr mRNA在8h~24h显著升高，其蛋白水平变化趋势与其一致，Ptger2 mRNA仅在 24h显著升高，其蛋白质含量并无显著变化，这提示PGF2α/PTGFR对崩解期子宫内膜崩解脱落具有重要作用。进一步，利用PTGFR抑制剂组能够抑制蜕膜化的基质细胞出现核固缩和坏死以及血管通透性，PTF2a/PTGFR通过血管通透性对子宫内膜崩解出血起作用。利用前列腺素合成酶COX-2能够抑制子宫内膜的崩解，参与的功能包括胞外基质、生长因子活性以及血管发生等紧密相关，且下调Hif-1信号通路表达。项目研究小组首次证实经典月经发生假说-前列腺素假说，为月经发生的机理以及子宫内膜异常出血诊断提供理论基础和临床实践基础。