Circulating microRNAs, novel biomarkers of acute myocardial infarction: a systemic review

Diagnostic and treatment value of XPNPEP3 in acute myocardial infarction

Background

At present, acute myocardial infarction (AMI) is a serious cardiovascular disease with high morbidity and mortality. Discovering biomarkers of AMI is important for clinical diagnosis and needs. Therefore, this study aimed to elucidate the role of XPNPEP3 as a potential biomarker for AMI.

Methods

Expression profiling data were downloaded for AMI patients and healthy patients in the GSE24548 and GSE24519 datasets, respectively. The limma package in R was conducted to determine differentially expressed microRNA (DEmiRNA)/messenger RNA (mRNA) [differentially expressed genes (DEGs)]. TargetScan and Cytoscape were used to build regulatory network of miRNA-mRNA. The Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) and Cell-type Identification by Estimating Relative Subsets of RNA Transcripts (CIBERSORT) were applied to determine immune cell score. The gene set variation analysis (GSVA) package was used to calculate pathway score. Key drugs were determined by protein-protein interaction (PPI) and molecular docking.

Results

Totals of 36 DEmiRNAs and 63 DEGs were determined in the GSE24584 dataset and GSE24519 dataset, respectively, and then we constructed a miRNA-mRNA network including 31 DEmiRNAs and 47 DEGs. The correlation analysis between immune cells and 47 DEGs identified that XPNPEP3 was most associated with AMI. Furthermore, XPNPEP3 was negatively correlated with inflammatory response score. A diagnosis model based on XPNPEP3 expression showed an area under the curve (AUC) of 93.38%, and 159 genes were highly correlated with XPNPEP3. Molecular docking analysis showed that DB06909 had the lowest docking score with XPNPEP3, revealing it to be a potential XPNPEP3 inhibitor.

Conclusions

This work discovered that XPNPEP3 is correlated with the development of AMI. These findings may provide theoretical basis for the diagnosis and treatment of AMI.

Fast and Simplified Method for High Through-put Isolation of miRNA from Highly Purified High Density Lipoprotein

Small non-coding RNAs (miRNAs) have been implicated in a variety of human diseases including metabolic syndromes. They may be utilized as biomarkers for diagnosis and prognosis or may serve as targets for drug development, respectively. Recently it has been shown that miRNAs are carried in lipoproteins, particularly high density lipoproteins (HDL) and are delivered to recipient cells for uptake. This raises the possibility that miRNAs play a critical and pivotal role in cellular and organ function via regulation of gene expression as well as messenger for cell-cell communications and crosstalk between organs. Current methods for miRNA isolation from purified HDL are impractical when utilizing small samples on a large scale. This is largely due to the time consuming and laborious methods used for lipoprotein isolation. We have developed a simplified approach to rapidly isolate purified HDL suitable for miRNA analysis from plasma samples. This method should facilitate investigations into the role of miRNAs in health and disease and in particular provide new insights into the variety of biological functions, outside of the reverse cholesterol transport, that have been ascribed to HDL. Also, the miRNA species which are present in HDL can provide valuable information of clinical biomarkers for diagnosis of various diseases.

Effect of transplantation of bone marrow stem cells on myocardial infarction size in a rabbit model

BACKGROUND

Intravenous transplantation has been regarded as a most safe method in stem cell therapies. There is evidence showing the homing of bone marrow stem cells (BMSCs) into the injured sites, and thus these cells can be used in the treatment of acute myocardial infarction (MI). This study aimed to investigate the effect of intravenous and epicardial transplantion of BMSCs on myocardial infarction size in a rabbit model.

METHODS

A total of 60 New Zealand rabbits were randomly divided into three groups: control group, epicardium group (group I) and ear vein group (group II). The BMSCs were collected from the tibial plateau in group I and group II, cultured and labeled. In the three groups, rabbits underwent thoracotomy and ligation of the middle left anterior descending artery. The elevation of ST segment >0.2 mV lasting for 30 minutes on the lead II and III of electrocardiogram suggested successful introduction of myocardial infarction. Two weeks after myocardial infarction, rabbits in group I were treated with autogenous BMSCs at the infarct region and those in group II received intravenous transplantation of BMSCs. In the control group, rabbits were treated with PBS following thoracotomy. Four weeks after myocardial infarction, the heart was collected from all rabbits and the infarct size was calculated. The heart was cut into sections followed by HE staining and calculation of infarct size with an image system.

RESULTS

In groups I and II, the infarct size was significantly reduced after transplantation with BMSCs when compared with the control group (P<0.05). However, there was no significant difference in the infarct size between groups I and II (P>0.05).

CONCLUSION

Transplantation of BMSCs has therapeutic effect on MI. Moreover, epicardial and intravenous transplantation of BMSCs has comparable therapeutic efficacy on myocardial infarction.