Priority Research Centre for Reproductive Sciences, School of Biomedical Sciences and Pharmacy, Faculty of Health and Medicine, University of Newcastle, Callaghan, New South Wales, Australia.
Pregnancy and Reproduction Program, Hunter Medical Research Institute, Newcastle, New South Wales, Australia.
Mol Hum Reprod. 2019 Apr 1;25(4):218-227. doi: 10.1093/molehr/gaz010.
In early gestation, the human placental renin-angiotensin system (RAS) is upregulated and plays a role in placental development. Among other functions, signalling through the angiotensin II type 1 receptor (AT1R) initiates proliferation. Many microRNAs (miRNAs) targeting placental RAS mRNAs are downregulated at this time. We propose that in early gestation miRNAs that target the placental RAS are downregulated, allowing for the increased RAS expression and proliferation required for adequate placentation. HTR-8/SVneo cells (an immortalized human trophoblast cell line) were used to assess the effect of nine miRNA mimics (at 0.08, 0.16, 0.32 and 0.64 ng/μL) on trophoblast cell proliferation and predicted RAS target mRNAs. The effect of the miRNA mimics on the rate of cell proliferation was assessed using the xCELLigence real-time cell analysis system over 48 h. Levels of miRNAs and predicted RAS target mRNAs were determined by RT-PCR (qPCR, n = 9/group). Statistically different levels of expression were determined (P < 0.05). All nine miRNA mimics significantly affected the proliferation rates of HTR-8/SVneo cells. Five of the miRNA mimics (miR-181a-5p (predicted to target: renin (REN), angiotensin converting enzyme (ACE)), miR-378 (REN, ACE), miR-663 (REN), miR-483-3p (ACE, ACE2, angiotensinogen (AGT), angiotensin II type 1 receptor (AGTR1)) and miR-514 (AGT)) were associated with a dose-dependent reduction in cell proliferation. Seven of the mimics significantly decreased expression of at least one of their predicted target RAS mRNAs. Our study shows that miRNAs targeting placental RAS mRNAs play a role in controlling trophoblast proliferation. As placentation is largely a process of proliferation, changes in expression of these miRNAs may be partly responsible for the expression of the placental RAS, proliferation and placentation.
在早期妊娠中，人胎盘肾素-血管紧张素系统（RAS）上调，并在胎盘发育中发挥作用。除其他功能外，血管紧张素 II 型 1 受体（AT1R）的信号转导启动增殖。此时，许多针对胎盘 RAS mRNA 的 microRNA（miRNA）下调。我们提出，在早期妊娠中，针对胎盘 RAS 的 miRNA 下调，允许增加 RAS 表达和增殖，以满足适当的胎盘形成。使用 HTR-8/SVneo 细胞（一种永生化的人滋养层细胞系）来评估九种 miRNA 模拟物（0.08、0.16、0.32 和 0.64ng/μL）对滋养层细胞增殖和预测的 RAS 靶 mRNA 的影响。使用 xCELLigence 实时细胞分析系统在 48 小时内评估 miRNA 模拟物对细胞增殖速度的影响。通过 RT-PCR（qPCR，n=9/组）确定 miRNA 和预测的 RAS 靶 mRNA 的水平。确定具有统计学差异的表达水平（P<0.05）。所有九种 miRNA 模拟物均显著影响 HTR-8/SVneo 细胞的增殖率。五种 miRNA 模拟物（miR-181a-5p（预测靶标：肾素（REN）、血管紧张素转换酶（ACE））、miR-378（REN、ACE）、miR-663（REN）、miR-483-3p（ACE、ACE2、血管紧张素原（AGT）、血管紧张素 II 型 1 受体（AGTR1））和 miR-514（AGT））与细胞增殖的剂量依赖性降低相关。七种模拟物显著降低了至少一种预测靶标 RAS mRNA 的表达。我们的研究表明，针对胎盘 RAS mRNA 的 miRNA 在控制滋养层细胞增殖中发挥作用。由于胎盘形成在很大程度上是一个增殖过程，这些 miRNA 的表达变化可能部分负责胎盘 RAS、增殖和胎盘形成的表达。
