AOPP诱导胎盘内质网应激在子痫前期发病中的作用和机制研究

Preeclampsia was a common pregnancy complication. Impaired differentiation of trophoblasts and imbalanced expression of invasive factors were major contributors to spiral arteries remodelling disturbance in preeclampsia. Excessive endoplasmic reticulum stress, which could induce cellular dysfunction, has been observed in preeclampsia placenta. Advanced oxidation protein products (AOPP) were one metabolite, which could induce excessive endoplasmic reticulum stress. We have showed patients with preeclampsia had a higher plasma and placental levels of AOPP. Moreover, the AOPP levels were associated with the severity of the disease. We proposed AOPP might be a novel substance which could cause impaired placental development and onset of preeclampsia. In this study, we explored the effect of AOPP on the rat placental endoplasmic reticulum stress level, placental development as well as the rate of preeclampsia. In addition, placental explants were incubated with various concentrations of AOPP. The effect of AOPP on the endoplasmic reticulum stress level, differentiation of trophoblasts and expression of invasive factors were investigated.

子痫前期（PE）是常见的妊娠期并发症。胎盘滋养细胞分化障碍、侵袭相关因子表达失衡是导致PE胎盘螺旋动脉重铸不良的重要原因。PE胎盘存在明显内质网应激。已经明确，过度内质网应激可导致细胞功能障碍。晚期氧化蛋白产物（AOPP）是一种具有高度生物活性的代谢产物，可引起细胞内质网应激。课题组前期研究发现AOPP在PE胎盘、血浆表达升高，并与患者病情严重程度密切相关。我们推测 AOPP 蓄积介导的内质网应激可能引起胎盘滋养细胞分化障碍、侵袭相关因子表达失衡，并导致子痫前期发生风险增加。本项研究我们通过动物实验，观察慢性AOPP 蓄积对妊娠大鼠胎盘内质网应激、滋养细胞分化以及子痫前期发生的影响。同时我们用不同浓度AOPP 刺激人早孕胎盘绒毛，观察其对胎盘内质网应激、滋养细胞分化和侵袭相关因子表达的影响，并探讨 AOPP诱导胎盘滋养细胞分化功能障碍和侵袭相关因子产生失衡可能的受体途及信号通路。

子痫前期是常见的妊娠期并发症，是目前围产期母胎死亡的主要原因之一。子痫前期一旦发生，终止妊娠、娩出“病变胎盘”是目前能够缓解子痫前期疾病进展的唯一手段和方法。滋养细胞作为胎盘最重要的组成部分，其细胞分化、侵袭、凋亡失衡与子宫-胎盘螺旋动脉重铸异常以及子痫前期发生密切相关。晚期氧化蛋白产物(AOPP)是血浆白蛋白被自由基和反应性氧系氧化后形成的蛋白交连产物。本课题组既往研究发现，子痫前期患者胎盘和血浆中AOPP表达水平明显高于正常孕妇，并且与子痫前期病情严重程度显著相关。综上所述，我们认为 AOPP 不仅参与子痫前期血管内皮功能障碍等病理环节，AOPP蓄积可能是引起滋养细胞功能异常的上游重要病理因素。因此，旨在探讨 AOPP 参与子痫前期发病中的机制，展开了以下相关的分支研究：（1）AOPP抑制滋养细胞增殖、侵袭和分化能力，并促进滋养细胞凋亡；（2）胰高血糖素样肽-1可抑制AOPP诱导的妊娠滋养细胞内活性氧的产生，同时抑制妊娠滋养细胞凋亡；（3）采用不同浓度AOPP 刺激人早孕胎盘绒毛，发现胎盘内质网应激及NF-Kb活性增加、滋养细胞分化和侵袭相关因子表达增加；（4）AOPP诱导氧化应激通路Nrf-2/ARE通路功能障碍导致滋养细胞过度凋亡。此外，我们发现（5）AOPP刺激滋养细胞分泌的外泌体可抑制内皮细胞迁移、成管及增殖，并对外泌体lncRNA测序找到了差异lncRNA AC092115.3，可调控EGR1/HSPA1B表达，并激活MAPK通路从而参与子痫前期发病机制。另外利用部分资助经费揭示了（6）子痫前期胎盘转录组测序找到差异的lncRNA调控滋养细胞迁移侵袭，此外发现（7）亲环素A经p38/ERK/JNK通路抑制滋养细胞迁移侵袭，并得到动物实验验证，还揭示（8）子痫前期胎盘RNA可变剪切存在调控紊乱的情况，及（9）人胚胎组织m6A表观遗传修饰差异表达谱。通过本研究进一步揭示AOPP在子痫前期胎盘功能障碍中的病理作用，为寻求子痫前期防治策略提供新的思路和证据。