Strengthening effects of bone marrow mononuclear cells with intensive atorvastatin in acute myocardial infarction

The Role of Stem Cells in the Treatment of Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of death and include several vascular and cardiac disorders, such as atherosclerosis, coronary artery disease, cardiomyopathies, and heart failure. Multiple treatment strategies exist for CVDs, but there is a need for regenerative treatment of damaged heart. Stem cells are a broad variety of cells with a great differentiation potential that have regenerative and immunomodulatory properties. Multiple studies have evaluated the efficacy of stem cells in CVDs, such as mesenchymal stem cells and induced pluripotent stem cell-derived cardiomyocytes. These studies have demonstrated that stem cells can improve the left ventricle ejection fraction, reduce fibrosis, and decrease infarct size. Other studies have investigated potential methods to improve the survival, engraftment, and functionality of stem cells in the treatment of CVDs. The aim of the present review is to summarize the current evidence on the role of stem cells in the treatment of CVDs, and how to improve their efficacy.

Follow-up of intramyocardial bone marrow mononuclear cell transplantation beyond 10 years

Bone marrow mononuclear cells (BMMCs) have been evaluated for their ability to improve cardiac repair and benefit patients with severe ischemic heart disease and heart failure. In our single-center trial in 2006-2011 we demonstrated the safety and efficacy of BMMCs injected intramyocardially in conjunction with coronary artery bypass surgery. The effect persisted in the follow-up study 5 years later. In this study, we investigated the efficacy of BMMC therapy beyond 10 years. A total of 18 patients (46%) died during over 10-years follow-up and 21 were contacted for participation. Late gadolinium enhancement cardiac magnetic resonance imaging (CMRI) and clinical evaluation were performed on 14 patients, seven from each group. CMRIs from the study baseline, 1-year and 5-years follow-ups were re-analyzed to enable comparison. The CMRI demonstrated a 2.1-fold larger reduction in the mass of late gadolinium enhancement values between the preoperative and the over 10-years follow-up, suggesting less scar or fibrosis after BMMC treatment (- 15.1%; 95% CI - 23 to - 6.7% vs. - 7.3%; 95% CI - 16 to 4.5%, p = 0.039), compared to placebo. No differences in mortality or morbidity were observed. Intramyocardially injected BMMCs may exert long-term benefits in patients with ischemic heart failure. This deserves further evaluation in patients who have received BMMCs in international clinical studies over two decades.

Atorvastatin-pretreated mesenchymal stem cell-derived extracellular vesicles promote cardiac repair after myocardial infarction via shifting macrophage polarization by targeting microRNA-139-3p/Stat1 pathway

BACKGROUND

Extracellular vesicles (EVs) derived from bone marrow mesenchymal stem cells (MSCs) pretreated with atorvastatin (ATV) (MSCATV-EV) have a superior cardiac repair effect on acute myocardial infarction (AMI). The mechanisms, however, have not been fully elucidated. This study aims to explore whether inflammation alleviation of infarct region via macrophage polarization plays a key role in the efficacy of MSCATV-EV.

METHODS

MSCATV-EV or MSC-EV were intramyocardially injected 30 min after coronary ligation in AMI rats. Macrophage infiltration and polarization (day 3), cardiac function (days 0, 3, 7, 28), and infarct size (day 28) were measured. EV small RNA sequencing and bioinformatics analysis were conducted for differentially expressed miRNAs between MSCATV-EV and MSC-EV. Macrophages were isolated from rat bone marrow for molecular mechanism analysis. miRNA mimics or inhibitors were transfected into EVs or macrophages to analyze its effects on macrophage polarization and cardiac repair in vitro and in vivo.

RESULTS

MSCATV-EV significantly reduced the amount of CD68+ total macrophages and increased CD206+ M2 macrophages of infarct zone on day 3 after AMI compared with MSC-EV group (P < 0.01-0.0001). On day 28, MSCATV-EV much more significantly improved the cardiac function than MSC-EV with the infarct size markedly reduced (P < 0.05-0.0001). In vitro, MSCATV-EV also significantly reduced the protein and mRNA expressions of M1 markers but increased those of M2 markers in lipopolysaccharide-treated macrophages (P < 0.05-0.0001). EV miR-139-3p was identified as a potential cardiac repair factor mediating macrophage polarization. Knockdown of miR-139-3p in MSCATV-EV significantly attenuated while overexpression of it in MSC-EV enhanced the effect on promoting M2 polarization by suppressing downstream signal transducer and activator of transcription 1 (Stat1). Furthermore, MSCATV-EV loaded with miR-139-3p inhibitors decreased while MSC-EV loaded with miR-139-3p mimics increased the expressions of M2 markers and cardioprotective efficacy.

CONCLUSIONS

We uncovered a novel mechanism that MSCATV-EV remarkably facilitate cardiac repair in AMI by promoting macrophage polarization via miR-139-3p/Stat1 pathway, which has the great potential for clinical translation.

Tongxinluo-pretreated mesenchymal stem cells facilitate cardiac repair via exosomal transfer of miR-146a-5p targeting IRAK1/NF-κB p65 pathway

Background

Bone marrow cells (BMCs), especially mesenchymal stem cells (MSCs), have shown attractive application prospects in acute myocardial infarction (AMI). However, the weak efficacy becomes their main limitation in clinical translation. Based on the anti-inflammation and anti-apoptosis effects of a Chinese medicine-Tongxinluo (TXL), we aimed to explore the effects of TXL-pretreated MSCs (MSCs^TXL) in enhancing cardiac repair and further investigated the underlying mechanism.

Methods

MSCs^TXL or MSCs and the derived exosomes (MSCs^TXL-exo or MSCs-exo) were collected and injected into the infarct zone of rat hearts. In vivo, the anti-apoptotic and anti-inflammation effects, and cardiac functional and histological recovery were evaluated. In vitro, the apoptosis was evaluated by western blotting and flow cytometry. miRNA sequencing was utilized to identify the significant differentially expressed miRNAs between MSCs^TXL-exo and MSCs-exo, and the miRNA mimics and inhibitors were applied to explore the specific mechanism.

Results

Compared to MSCs, MSCs^TXL enhanced cardiac repair with reduced cardiomyocytes apoptosis and inflammation at the early stage of AMI and significantly improved left ventricular ejection fraction (LVEF) with reduced infarct size in an exosome-dependent way. Similarly, MSCs^TXL-exo exerted superior therapeutic effects in anti-apoptosis and anti-inflammation, as well as improving LVEF and reducing infarct size compared to MSCs-exo. Further exosomal miRNA analysis demonstrated that miR-146a-5p was the candidate effector of the superior effects of MSCs^TXL-exo. Besides, miR-146a-5p targeted and decreased IRAK1, which inhibited the nuclear translocation of NF-κB p65 thus protecting H9C2 cells from hypoxia injury.

Conclusions

This study suggested that MSCs^TXL markedly facilitated cardiac repair via a new mechanism of the exosomal transfer of miR-146a-5p targeting IRAK1/NF-κB p65 pathway, which has great potential for clinical translation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02969-y.

Pharmacogenomics and circadian rhythms as mediators of cardiovascular drug-drug interactions

This article summarizes the current literature and documents new evidence concerning drug-drug interactions (DDI) stemming from pharmacogenomic and circadian rhythm determinants of therapies used to treat common cardiovascular diseases (CVD), such as atherosclerosis and hypertension. Patients with CVD often have more than one pathophysiologic condition, namely metabolic syndromes, hypertension, hyperlipidemia, and hyperglycemia, among others, which necessitate polytherapeutic or polypharmaceutic management. Interactions between drugs, drugs and food/food supplements, or drugs and genetic/epigenetic factors may have adverse impacts on the cardiovascular and other systems of the body. The mechanisms underlying cardiovascular DDI may involve the formation of a complex pharmacointeractome, including the absorption, distribution, metabolism, and elimination of drugs, which affect their respective bioavailability, efficacy, and/or harmful metabolites. The pharmacointeractome of cardiovascular drugs is likely operated with endogenous rhythms controlled by circadian clock genes. Basic and clinical investigations have improved the knowledge and understanding of cardiovascular pharmacogenomics and pharmacointeractomes, and additionally they have presented new evidence that the staging of deterministic circadian rhythms, according to the dosing time of drugs, e.g., upon awakening vs. at bedtime, cannot only differentially impact their pharmacokinetics and pharmacodynamics but also mediate agonistic/synergetic or antagonistic DDI. To properly manage CVD patients and avoid DDI, it is important that clinicians have sufficient knowledge of their multiple risk factors, i.e., age, gender, and life style elements (like diet, smoking, psychological stress, and alcohol consumption), and comorbidities, such as diabetes, hypertension, dyslipidemia, and depression, and the potential interactions between genetic or epigenetic background of their prescribed therapeutics.

Atorvastatin Pretreatment Ameliorates Mesenchymal Stem Cell Migration through miR-146a/CXCR4 Signaling

BACKGROUND

We previously found that atorvastatin (ATV) enhanced mesenchymal stem cells (MSCs) migration, by a yet unknown mechanism. CXC chemokine receptor 4 (CXCR4) is critical to cell migration and regulated by microRNA-146a (miR-146a). Therefore, this study aimed to assess whether ATV ameliorates MSCs migration through miR-146a/CXCR4 signaling.

METHODS

Expression of CXCR4 was evaluated by flow cytometry. Expression of miR-146a was examined by reverse transcription-quantitative polymerase chain reaction. A transwell system was used to assess the migration ability of MSCs. Recruitment of systematically delivered MSCs to the infarcted heart was evaluated in Sprague-Dawley rats with acute myocardial infarction (AMI). Mimics of miR-146a were used in vitro, and miR-146a overexpression lentivirus was used in vivo, to assess the role of miR-146a in the migration ability of MSCs.

RESULTS

The results showed that ATV pretreatment in vitro upregulated CXCR4 and induced MSCs migration. In addition, flow cytometry demonstrated that miR-146a mimics suppressed CXCR4, and ATV pretreatment no longer ameliorated MSCs migration because of decreased CXCR4. In the AMI model, miR-146a-overexpressing MSCs increased infarct size and fibrosis.

CONCLUSION

The miR-146a/CXCR4 signaling pathway contributes to MSCs migration and homing induced by ATV pretreatment. miR-146a may be a novel therapeutic target for stimulating MSCs migration to the ischemic tissue for improved repair.