[MicroRNA-221/222 participates in the pathogenesis of intrahepatic cholestasis of pregnancy via promoting the apoptosis of human placental trophoblast HTR-8 cells].

Objective: MicroRNA-221/222 is involved in the pathogenesis of intrahepatic cholestasis of pregnancy (ICP) to promote the apoptosis of placental bile acids through human trophoblastic cells. This study investigates the effects of miR-221/222 on proliferation, apoptosis and apoptosis-related proteins of human trophoblast HTR-8/SVneo (HTR-8 cells) to understand its role in promoting trophoblastic apoptosis. Methods: The experiment was divided into transfection group and negative control group. Transient transfection method was used in both groups. The transfection efficiency was detected by RT-QPCR after 48 h transfection. CCK-8 was used to detect the proliferation of HTR-8 cells and the apoptosis of HTR-8 cells were analyzed by flow cytometry. Western blot was used to detect the expression of B-cell Lymphoma 2 (Bcl-2) in HTR-8 cells. Data were compared with t-test. Results: The expression of miR-221/222 transfected group (25.43±0.80, 22.70±0.95) was increased significantly in the HTR-8 cells than that to negative control group (1.14±0.14, 1.58±0.14), and P value was < 0.01, the difference was statistically significant. The expression of Bcl-2 protein in mir-221/222 transfection group was (0.56 ± 0.03, 0.53 ± 0.03), and the protein expression was decreased compared with negative control group (0.72 ± 0.003, 0.76 ± 0.04). P value was < 0.05, the difference was statistically significant, and compared with the mir-221/222 negative control group (8.827 ± 0.48, 11.80 ± 0.45), cell apoptosis of mir-221/222 transfection group (42.53 ± 4.47, 24.09 ± 2.53) increased significantly, P value was < 0.01, and the difference was statistically significant. Proliferation rate in mir-221/222 transfection group was (0.82 ± 0.02, 0.74±0.01), and proliferation was inhibited, when compared with control group (1.15 ± 0.08, 1.06 ± 0.08), P value was < 0.05, and the difference was statistically significant. Conclusion: miR-221/222 may promote the apoptosis of human trophoblastic cells by down regulating the expression of apoptosis inhibitory protein bcl-2, leading to placental dysfunction and impairing the normal bile acid transport function of placenta. This mechanism may be involved in the occurrence and development of ICP.目的： 研究miR-221/222对人滋养细胞HTR-8/SVneo（简称HTR-8细胞）增殖、凋亡和凋亡相关蛋白的影响，了解其促人滋养细胞凋亡作用，探讨miR-221/222通过促进人滋养细胞凋亡损害胎盘胆汁酸转运功能，参与妊娠期肝内胆汁淤积症（ICP）发生与发展的机制。 方法： 实验分为转染组和阴性对照组，转染组用瞬时转染方法将miR-221/222 mimic转入HTR-8细胞中，阴性对照组用相同方法将mimic NC转入HTR-8细胞。转染48 h后用RT-qPCR检测转染效率，CCK-8检测HTR-8细胞增殖情况，流式细胞术分析HTR-8细胞凋亡变化，Western blot检测HTR-8细胞内凋亡抑制蛋白B-cell lymphoma 2（简称bcl-2）的表达。数据比较用t检验。 结果： 与阴性对照组（1.14 ± 0.14、1.58 ± 0.14）相比，miR-221/222转染组（25.43 ± 0.80、22.70 ± 0.95）在HTR-8细胞内表达量明显升高，P值均<0.01，差异具有统计学意义；miR-221/222转染组bcl-2蛋白表达量分别为（0.56 ± 0.03、0.53 ± 0.03），与各自阴性对照组（0.72 ± 0.003、0.76 ± 0.04）相比，蛋白表达量下降，P值均<0.05，差异具有统计学意义；与miR-221/222阴性对照组（8.827 ± 0.48、11.80 ± 0.45）相比，miR-221/222转染组（42.53 ± 4.47、24.09 ± 2.53）细胞凋亡明显增加，P值均<0.01，差异具有统计学意义；miR-221/222转染组增殖率分别为（0.82 ± 0.02、0.74 ± 0.01），与对照组（1.15 ± 0.08、1.06 ± 0.08）相比增殖被抑制，P值均<0.05，差异具有统计学意义。 结论： miR-221/222可能通过下调凋亡抑制蛋白bcl-2的表达促进人滋养细胞凋亡，导致胎盘功能障碍，损害胎盘正常胆汁酸转运功能，其机制可能参与了ICP的发生与发展。.