低氧相关微小RNA-210/Tet2/IL-6调控轴在子痫前期中的作用及其机制研究

Pathogenesis of preeclampsia(PE) has not been fully understood, but it’s characterization of widespread aseptic inflammation and endothelial dysfunction were well recognized. Recent reports showed marked elevation of hypoxia-induced microRNA-210(miR-210) and interleukin 6(IL-6) in PE second-third trimester serum. Using bioinformation analysis, we found Ten-eleven translocation 2(Tet2) was one of the targets of miR-210. Tet2 was reported as a transcription inhibitor of IL-6. Preliminary experiment showed that, compared with that in normal pregnancy, serum IL-6 was higher in Tet2 knock out pregnancy mice. Based on literature and preliminary results, we hypothesized that miR-210/Tet2/IL-6 regulating axis may contribute to PE. We plan to demonstrate the relationship of miR-210/Tet2/IL-6 in trophoblast/serum/placenta, making use of the miR-210 knockout and Tet2 knockout pregnancy mice, human PE serum/placenta and trophoblast cells. This study may provide novel clues for pathogenesis of PE and new molecular target of PE therapy.

子痫前期(PE)的病理机制尚不清楚，但其特征包括广泛的无菌性炎症和内皮细胞功能紊乱。新近发现，PE患者血液中，低氧诱导的miR-210和炎性介质IL-6浓度均显著升高，且两者正相关。课题组应用生物信息学分析发现miR-210的靶点包括Tet2，而Tet2是IL-6的转录抑制子，预实验发现Tet2敲除妊娠小鼠血清IL-6浓度大幅升高。综合前期及国内外研究成果，提出：“机体内存在miR-210/Tet2/IL-6调控轴，在妊娠期各种因素诱导下，该调控轴传导异常，IL-6表达过度，导致内皮细胞严重受损，引发PE发生”。为证实该假说：我们将①研究妊娠期母体血液miR-210和IL-6变化规律及其与PE的关系；②研究胎盘中miR-210、Tet2/IL-6相关性及其与PE的关系；③在滋养细胞和基因敲除小鼠模型中，研究miR-210对Tet2/IL-6的调控机制，为PE的发生机制阐明和治疗提供新思路。

子痫前期(pre-eclampsia，PE)是妊娠期特有的、严重危害母亲和胎儿健康的多器官损伤综合征,其发生机制尚不清楚，但具有共同的病理学基础：广泛的无菌性炎症和内皮细胞功能紊乱。深入研究PE的发病机制将有利于PE的治疗。综合前期及国内外研究成果，我们提出“机体内可能存在缺氧/miR-210/Tet2/IL-6调控轴，在妊娠期多种因素作用下，该调控轴传导异常，miR-210异常高表达，通过Tet2传导，IL-6表达异常，血管内皮细胞严重受损，引发PE发生”。本课题收集了PE和正常妊娠对照的血清和胎盘,利用荧光定量PCR法和ELISA法分别检测了血清miR-210、IL-6的表达水平,发现PE患者妊娠中晚期血清中的miR-210和IL-6升高,且miR-210和IL-6之间存在正相关关系。利用免疫组化法检测了胎盘IL-6、Tet2的表达，发现在合体滋养细胞和细胞滋养细胞中均有IL-6和Tet2的表达，PE组的IL-6蛋白表达高于正常对照组，PE组的Tet2蛋白表达低于对照组。低氧培养引起滋养细胞miR-210表达升高，进一步利用miR-210模拟子和抑制子处理原代滋养细胞或滋养细胞系，检测miR-210、IL-6、Tet2 mRNA及蛋白的表达情况并分析其相关性，发现：miR-210升高对IL-6、Tet2的mRNA和蛋白表达没有显著影响。荧光素酶报告基因实验表明Tet2可能不是miR-210的直接靶基因。根据以上实验结果，得到本课题结论：与正常妊娠组相比，PE组孕中期、孕晚期IL-6、miR-210增多，孕中晚期血清IL-6/miR-210可能是PE诊断和预测的良好生物标志物；妊娠期血清IL-6和miR-210的表达存在正相关关系,但相关性较弱,且两者之间的相关性可能不是通过Tet2介导的。项目研究成果已经在中华检验医学杂志等期刊发表论文2篇。