MicroRNA-326-5p enhances therapeutic potential of endothelial progenitor cells for myocardial infarction

Abstract

BackgroundOur study sought to investigate the therapeutic effects and mechanisms of miR-326-5p-overexpressing endothelial progenitor cells (EPCs) on acute myocardial infarction (AMI).MethodsMouse EPCs were isolated, purified, and identified by flow cytometry and uptake of DiI-ac-LDL. The target gene of miR-326-5p was predicted using target prediction algorithms and verified by dual-luciferase reporter assay, RT-qPCR, and Western blot. After EPCs were transfected with the agomir or antagomir of miR-326-5p, tube formation assay and Matrigel plug angiogenesis assay were conducted in four groups (NC, miR-326-5p agomir, miR-326-5p antagomir, and miR-326-5p agomir+Wnt1 agonist). In addition, a mouse model of MI was established and treated with the injection of miR-326-5p-EPCs, miR-326-5p-EPCs+ Wnt1 agonist, EPCs-NC, or PBS/control into the peri-infarcted myocardium. Subsequently, cardiac function was monitored by echocardiography at 7 and 28 days postoperatively. Finally, the infarcted hearts were collected at 28 days, and the size of myocardial infarction was measured by Masson’s trichrome staining and the neovascularization in the peri-infarcted area was examined through immunofluorescence staining.ResultsLuciferase reporter assay indicated that Wnt1 was a direct target of miR-326-5p. Using RT-qPCR and Western blot analysis, we further demonstrated that the expression level of Wnt1 was negatively correlated with miR-326-5p expression in EPCs. Both in vitro study of tube formation assay and in vivo investigation of subcutaneous Matrigel plug assay revealed that the miR-326-5p agomir could significantly enhance the angiogenic capacity of EPCs, and this effect was partially inhibited by Wnt1 agonist. Meanwhile, miR-326-5p antagomir could obviously reduce the the angiogenic capacity of EPCs in vivo compared with that in the NC group. Moreover, the transplantation of miR-326-5p-overexpressing EPCs in the ischemic hearts of mice significantly enhanced the angiogenesis in the peri-infarcted zone and improved the cardiac function. However, the enhanced capacity of angiogenesis of miR-326-5p-overexpressing EPCs was remarkably neutralized by Wnt1 agonist, accompanied by the decreased improvement in cardiac function.ConclusionmiR-326-5p significantly enhanced the angiogenic capacity of EPCs. Transplantation of miR-326-5p-overexpressing EPCs improved cardiac function for AMI therapy, which can be a novel strategy for enhancing therapeutic angiogenesis in ischemic heart diseases.

RETRACTED ARTICLE: Restored microRNA-326-5p Inhibits Neuronal Apoptosis and Attenuates Mitochondrial Damage via Suppressing STAT3 in Cerebral Ischemia/Reperfusion Injury

“…Also, miR-326 expression has been further evidenced to reduce in Parkinson's disease and miR-326 could suppress apoptosis of dopaminergic neurons and reduce inflammatory response [ 25 ]. Except for that, the reduction in miR-326-5p is manifested in endothelial progenitor cells in the course of myocardial infarction, and introduction of endothelial progenitor cells overexpressing could promote cardiac function recovery [ 11 ]. There has been a study illustrating that up-regulation of miR-326 improves the behavioral function, enhances neuronal viability and depresses neuronal apoptosis in mice with Alzheimer's disease [ 26 ].…”

“…Additionally, it is found that up-regulation of miR-98 improves neurological outcomes in mice with I/R stroke [ 9 ] and overexpression of miR-451 alleviates ischemic cerebral apoptosis in mice with CI/RI [ 10 ]. Specifically, miR-326-5p has pro-angiogenic ability for endothelial progenitor cells and could improve cardiac function after acute myocardial infarction [ 11 ]. However, the study pivoting on miR-326-5p in CI/RI is still in its infancy.…”

Hypoxic preconditioning rejuvenates mesenchymal stem cells and enhances neuroprotection following intracerebral hemorrhage via the miR-326-mediated autophagy

“…Previous researches have not shown that miR-326 is involved in the regulation of cellular senescence. However, a previous study demonstrated that miR-326 overexpressing endothelial progenitor cells could enhance therapeutic angiogenesis in myocardial infarction [ 44 ]. MiR-326 overexpression has been found to inhibit apoptosis and promote the proliferation of neurons in cerebral ischemia-reperfusion injury [ 45 ], Parkinson’s disease [ 46 , 47 ], and Alzheimer’s disease [ 48 ].…”

“…Overexpression of miR-326 was found to improve the therapeutic effect of human umbilical cord mesenchymal stem cell-derived exosomes in mice with inflammatory bowel disease [ 75 ]. MiR-326-5p also significantly enhanced the angiogenic capacity of endothelial progenitor cells in ischemic heart diseases [ 44 ]. The results of our experiments demonstrate that miR-326 plays a major role in the reduced cellular senescence of hypoxia OM-MSCs.…”

Cellular Senescence Affects Cardiac Regeneration and Repair in Ischemic Heart Disease

“…EPCs can not only promote the recovery of ECs after injury but also stimulate angiogenesis after AMI[ 131 ]. EPCs can be significantly mobilized from the bone marrow to the peripheral circulation, home to the ischemic heart, differentiate into mature ECs, and initiate the repair process of neovascularization [ 132 , 133 ]. Long-term exposure to risk factors, such as smoking, glycosuria, hypertension, hyperlipidemia and/or cardiovascular disease, in aging can reduce the number of EPCs, and a low EPC count is associated with a high mortality in patients with coronary heart disease [ 134 ].…”