Dakhlallah Duaa, Zhang Jianying, Yu Lianbo, Marsh Clay B, Angelos Mark G, Khan Mahmood
*Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH; †Department of Engineering, American University of the Safat, Kuwait; ‡Department of Biomedical Informatics, Center for Biostatistics, The Ohio State University, Columbus, OH; and §Department of Emergency Medicine, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH.
J Cardiovasc Pharmacol. 2015 Mar;65(3):241-51. doi: 10.1097/FJC.0000000000000183.
: Cardiovascular disease is the number 1 cause of morbidity and mortality in the United States. The most common manifestation of cardiovascular disease is myocardial infarction (MI), which can ultimately lead to congestive heart failure. Cell therapy (cardiomyoplasty) is a new potential therapeutic treatment alternative for the damaged heart. Recent preclinical and clinical studies have shown that mesenchymal stem cells (MSCs) are a promising cell type for cardiomyoplasty applications. However, a major limitation is the poor survival rate of transplanted stem cells in the infarcted heart. miR-133a is an abundantly expressed microRNA (miRNA) in the cardiac muscle and is downregulated in patients with MI. We hypothesized that reprogramming MSCs using miRNA mimics (double-stranded oligonucleotides) will improve survival of stem cells in the damaged heart. MSCs were transfected with miR-133a mimic and antagomirs, and the levels of miR-133a were measured by quantitative real-time polymerase chain reaction. Rat hearts were subjected to MI and MSCs transfected with miR-133a mimic or antagomir were implanted in the ischemic hearts. Four weeks after MI, cardiac function, cardiac fibrosis, miR-133a levels, and apoptosis-related genes (Apaf-1, Caspase-9, and Caspase-3) were measured in the heart. We found that transfecting MSCs with miR-133a mimic improves survival of MSCs as determined by the MTT assay. Similarly, transplantation of miR-133a mimic transfected MSCs in rat hearts subjected to MI led to a significant increase in cell engraftment, cardiac function, and decreased fibrosis when compared with MSCs only or MI groups. At the molecular level, quantitative real-time polymerase chain reaction data demonstrated a significant decrease in expression of the proapoptotic genes; Apaf-1, caspase-9, and caspase-3 in the miR-133a mimic transplanted group. Furthermore, luciferase reporter assay confirmed that miR-133a is a direct target for Apaf-1. Overall, bioengineering of stem cells through miRNAs manipulation could potentially improve the therapeutic outcome of patients undergoing stem cell transplantation for MI.
心血管疾病是美国发病和死亡的首要原因。心血管疾病最常见的表现是心肌梗死（MI），最终可导致充血性心力衰竭。细胞疗法（心肌成形术）是受损心脏一种新的潜在治疗选择。最近的临床前和临床研究表明，间充质干细胞（MSCs）是心肌成形术应用中一种很有前景的细胞类型。然而，一个主要限制是梗死心脏中移植干细胞的存活率低。miR-133a是心肌中大量表达的微小RNA（miRNA），在MI患者中表达下调。我们假设使用miRNA模拟物（双链寡核苷酸）对MSCs进行重编程将提高受损心脏中干细胞的存活率。用miR-133a模拟物和拮抗剂转染MSCs，并通过定量实时聚合酶链反应测量miR-133a的水平。对大鼠心脏进行MI，并将用miR-133a模拟物或拮抗剂转染的MSCs植入缺血心脏。MI后四周，测量心脏的心脏功能、心肌纤维化、miR-133a水平和凋亡相关基因（Apaf-1、Caspase-9和Caspase-3）。我们发现，用MTT法测定，用miR-133a模拟物转染MSCs可提高其存活率。同样，与仅MSCs组或MI组相比，将用miR-133a模拟物转染的MSCs移植到MI大鼠心脏中可导致细胞植入显著增加、心脏功能改善和纤维化减少。在分子水平上，定量实时聚合酶链反应数据表明，miR-133a模拟物移植组中促凋亡基因Apaf-1、caspase-9和caspase-3的表达显著降低。此外，荧光素酶报告基因测定证实miR-133a是Apaf-1的直接靶点。总体而言，通过操纵miRNAs对干细胞进行生物工程改造可能会改善接受MI干细胞移植患者的治疗效果。
