Department of Emergency, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China.
Department of Cardiology, The First People's Hospital of Pingyuan County, Dezhou, Shandong, China.
Life Sci. 2020 Sep 1;256:117852. doi: 10.1016/j.lfs.2020.117852. Epub 2020 May 27.
Atherosclerosis (AS) performs the important pathogenesis which refers to coronaryheart and vascular diseases. Long non-coding RNAs (lncRNAs) was reported to be related to the AS progression. We aimed to probe the role and potential mechanism of Myocardial Infarction Associated Transcript (MIAT) in AS.
Levels of MIAT, microRNA-148b (miR-148b) and pregnancy-associated plasma protein A (PAPPA) were detected by quantitative Real-time polymerase chain reaction (qRT-PCR) in oxidized low-density lipoprotein (ox-LDL)-induced human aorta vascular smooth muscle cells (HA-VSMCs). Proliferation and migration were examined by Cell counting kit-8 (CCK-8) and wound-healing assays, respectively. Protein levels of Ki-67, proliferating cell nuclear antigen (PCNA), matrix metalloproteinase (MMP)-2, MMP-9 and PAPPA were examined by western blot assay. Ki-67 and PCNA level was detected by flow cytometry. The interaction among MIAT, miR-148b and PAPPA was confirmed via dual-luciferase reporter and RNA immunoprecipitation (RIP). The biology role of MIAT was detected by an AS model in vivo.
The levels of MIAT and PAPPA were augmented, whereas mature miR-148b level was repressed in ox-LDL-induced AS model. The inhibitory effects of knockdown of MIAT on proliferation and migration were relieved by miR-148b inhibitor. Additionally, miR-148b regulated proliferation and migration by targeting PAPPA. Mechanically, MIAT functioned as sponge of miR-148b to impact PAPPA expression. MIAT knockdown protected AS mice against lipid metabolic disorders in vivo.
Proliferation and migration were modified by MIAT/miR-148b/PAPPA axis in ox-LDL induced AS cell model, supplying a novel insight into the underlying application of MIAT in the clinical treatment of AS.
动脉粥样硬化（AS）是冠心病和血管疾病的重要发病机制。长链非编码 RNA（lncRNA）与 AS 进展有关。本研究旨在探讨心肌梗死相关转录物（MIAT）在 AS 中的作用及潜在机制。
采用实时定量聚合酶链反应（qRT-PCR）检测氧化型低密度脂蛋白（ox-LDL）诱导的人主动脉血管平滑肌细胞（HA-VSMCs）中 MIAT、微小 RNA-148b（miR-148b）和妊娠相关血浆蛋白 A（PAPPA）的水平。采用细胞计数试剂盒-8（CCK-8）和划痕愈合实验分别检测细胞增殖和迁移。采用 Western blot 检测 Ki-67、增殖细胞核抗原（PCNA）、基质金属蛋白酶（MMP）-2、MMP-9 和 PAPPA 的蛋白水平。采用流式细胞术检测 Ki-67 和 PCNA 水平。通过双荧光素酶报告和 RNA 免疫沉淀（RIP）验证 MIAT、miR-148b 和 PAPPA 之间的相互作用。通过体内 AS 模型检测 MIAT 的生物学作用。
在 ox-LDL 诱导的 AS 模型中，MIAT 和 PAPPA 的水平升高，而成熟 miR-148b 的水平降低。miR-148b 抑制剂减弱了 MIAT 敲低对增殖和迁移的抑制作用。此外，miR-148b 通过靶向 PAPPA 调节增殖和迁移。机制上，MIAT 作为 miR-148b 的海绵体影响 PAPPA 的表达。MIAT 敲低可减轻体内 AS 小鼠的脂质代谢紊乱。
在 ox-LDL 诱导的 AS 细胞模型中，MIAT/miR-148b/PAPPA 轴改变了增殖和迁移，为 MIAT 在 AS 临床治疗中的潜在应用提供了新的见解。
