Circulating miR-208b: A Potentially Sensitive and Reliable Biomarker for the Diagnosis and Prognosis of Acute Myocardial Infarction

Plasma microRNAs as potential biomarkers in diagnosis of acute venous thromboembolism

OBJECTIVE

To assess the potential use of plasma microRNAs (miRNAs) in diagnosis of acute venous thromboembolism (VTE).

METHODS

Using BGISEQ-500 sequencing technology, we analyzed the miRNA profile of paired plasma samples from the acute and chronic phases of four patients with unprovoked VTE. Using real-time quantitative polymerase chain reaction (RT-qPCR), we verified nine upregulated named miRNAs in the acute phase in the plasma samples of 54 patients with acute VTE and 39 controls. We then compared the relative expression of the 9 candidate miRNAs between the acute VTE and control group, and plotted the receiver operating characteristic (ROC) curves of the differentially expressed miRNAs. We chose the miRNA with the greatest area under curve (AUC) to evaluate the effect of miRNA on coagulation and platelet function in the plasma samples of 5 healthy volunteers.

RESULTS

The plasma levels of miR-374b-3p, miR-660-5p, miR-378a-3p, miR-425-5p, miR-3613-5p, miR-130b-3p, miR-183-5p, and miR-103b were higher in patients with acute VTE than in the controls, with AUCs of 0.6776, 0.6614, 0.6648, 0.6885, 0.8048, 0.6871, 0.7298, and 0.7498, respectively, and P values of 0.0036, 0.0081, 0.0069, 0.0020,<0.0001, 0.0022, 0.0002, and < 0.0001, respectively. There were no significant differences in miR-193b-5p level between the acute VTE group and the control group. Fibrinogen (Fib), thrombin- antithrombin complex (TAT), tissue plasminogen activator-inhibitor complex (t-PAIC), and TAT/plasmin-α2-plasmin inhibitor complex (PIC) were decreased in the miR-3613-5p group when compared with the control group (P < 0.05) and the mean platelet aggregation rate was increased in the miR-3613 group (P < 0.05).

CONCLUSION

miRNAs can be potential biomarkers for diagnosing acute VTE, and miR-3613-5p may be involved in the formation, coagulation, and platelet functions in acute VTE.

Salivary microRNA and Metabolic Profiles in a Mouse Model of Subchronic and Mild Social Defeat Stress

Identification of early biomarkers of stress is important for preventing mood and anxiety disorders. Saliva is an easy-to-collect and non-invasive diagnostic target. The aim of this study was to characterize the changes in salivary whole microRNAs (miRNAs) and metabolites in mice subjected to subchronic and mild social defeat stress (sCSDS). In this study, we identified seven upregulated and one downregulated miRNAs/PIWI-interacting RNA (piRNA) in the saliva of sCSDS mice. One of them, miR-208b-3p, which is reported as a reliable marker for myocardial infarction, was upregulated in the saliva of sCSDS mice. Histological analysis showed frequent myocardial interstitial fibrosis in the heart of such mice. In addition, gene ontology and pathway analyses suggested that the pathways related to energy metabolism, such as the oxidative phosphorylation and the pentose phosphate pathway, were significantly related to the miRNAs affected by sCSDS in saliva. In contrast, salivary metabolites were not significantly changed in the sCSDS mice, which is consistent with our previous metabolomic study on the plasma of sCSDS mice. Taken in the light of previous studies, the present study provides novel potential stress biomarkers for future diagnosis using saliva.

Metabolic labeling of cardiomyocyte-derived small extracellular-vesicle (sEV) miRNAs identifies miR-208a in cardiac regulation of lung gene expression

Toxoplasma gondii uracil phosphoribosyltransferase (UPRT) converts 4-thiouracil (4TUc) into 4-thiouridine (4TUd), which is incorporated into nascent RNAs and can be biotinylated, then labelled with streptavidin conjugates or isolated via streptavidin-affinity methods. Here, we generated mice that expressed T. gondii UPRT only in cardiomyocytes (CM UPRT mice) and tested our hypothesis that CM-derived miRNAs (CM miRs) are transferred into remote organs after myocardial infarction (MI) by small extracellular vesicles (sEV) that are released from the heart into the peripheral blood (PB sEV). We found that 4TUd was incorporated with high specificity and sensitivity into RNAs isolated from the hearts and PB sEV of CM UPRT mice 6 h after 4TUc injection. In PB sEV, 4TUd was incorporated into CM-specific/enriched miRs including miR-208a, but not into miRs with other organ or tissue-type specificities. 4TUd-labelled miR208a was also present in lung tissues, especially lung endothelial cells (ECs), and CM-derived miR-208a (CM miR-208a) levels peaked 12 h after experimentally induced MI in PB sEV and 24 h after MI in the lung. Notably, miR-208a is expressed from intron 29 of α myosin heavy chain (αMHC), but αMHC transcripts were nearly undetectable in the lung. When PB sEV from mice that underwent MI (MI-PB sEV) or sham surgery (Sham-PB sEV) were injected into intact mice, the expression of Tmbim6 and NLK, which are suppressed by miR-208a and cooperatively regulate inflammation via the NF-κB pathway, was lower in the lungs of MI-PB sEV-treated animals than the lungs of animals treated with Sham-PB sEV or saline. In MI mice, Tmbim6 and NLK were downregulated, whereas endothelial adhesion molecules and pro-inflammatory cells were upregulated in the lung; these changes were significantly attenuated when the mice were treated with miR-208a antagomirs prior to MI surgery. Thus, CM UPRT mice enables us to track PB sEV-mediated transport of CM miRs and identify an miR-208a-mediated mechanism by which myocardial injury alters the expression of genes and inflammatory response in the lung.

Human Heart Anoxia and Reperfusion Tissue (HEART) Model for the Rapid Study of Exosome Bound miRNA Expression As Biomarkers for Myocardial Infarction

Current biomarkers for myocardial infarction (MI) diagnosis are typically late markers released upon cell death, incapable of distinguishing between ischemic and reperfusion injury and can be symptoms of other pathologies. Circulating microRNAs (miRNAs) have recently been proposed as alternative biomarkers for MI diagnosis; however, detecting the changes in the human cardiac miRNA profile during MI is extremely difficult. Here, to study the changes in miRNA levels during acute MI, a heart-on-chip model with a cardiac channel, containing human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes in human heart decellularized matrix and collagen, and a vascular channel, containing hiPSC-derived endothelial cells, is developed. This model is exposed to anoxia followed by normoxia to mimic ischemia and reperfusion, respectively. Using a highly sensitive miRNA biosensor that the authors developed, the exact same increase in miR-1, miR-208b, and miR-499 levels in the MI-on-chip and the time-matched human blood plasma samples collected before and after ischemia and reperfusion, is shown. That the surface marker profile of exosomes in the engineered model changes in response to ischemic and reperfusion injury, which can be used as biomarkers to detect MI, is also shown. Hence, the MI-on-chip model developed here can be used in biomarker discovery.

Circular RNA circ_0001445 alleviates the ox-LDL-induced endothelial injury in human primary aortic endothelial cells through regulating ABCG1 via acting as a sponge of miR-208b-5p

BACKGROUND

Coronary artery disease (CAD) originates from the blockage of the inner walls of the coronary arteries due to a plaque buildup. Circular RNA (circRNA) circ_0001445 has been reported to be downregulated in patients with a higher coronary atherosclerotic burden. This study is designed to explore the role and mechanism of circ_0001445 on the oxidized low-density lipoprotein (ox-LDL)-induced endothelial cell damage.

METHODS

Circ_0001445, microRNA-208b-5p (miR-208b-5p), and ATP-binding cassette sub-family G member 1 (ABCG1) levels were detected by real-time quantitative polymerase chain reaction (RT-qPCR). Inflammatory cytokines levels, cell viability, proliferation, migration were detected by Enzyme-linked immunosorbent assay (ELISA) kits, Cell Counting Kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EdU), and transwell assays, respectively. Protein levels were determined by western blot assay. The binding between miR-208b-5p and circ_0001445 or ABCG1 was predicted by circBank or TargetScan, and then verified by a dual-luciferase reporter, RNA Immunoprecipitation (RIP), and RNA pull-down assays.

RESULTS

Circ_0001445 and ABCG1 were decreased, and miR-208b-5p was increased in CAD patients and ox-LDL-treated HAECs. Also, circ_0001445 overexpression could weaken ox-LDL-triggered HAEC injury by boosting proliferation, migration, and repressing inflammation and extracellular matrix (ECM). Mechanically, circ_0001445 directly targeted miR-208b-5p. Furthermore, miR-208b-5p mediated the modulation of circ_0001445 in ox-LDL-induced HAEC injury. ABCG1 acted as a direct target of miR-208b-5p, and the downregulation of miR-208b-5p relieved ox-LDL-induced HAEC damage by interacting with ABCG1. Additionally, circ_0001445 regulated ABCG1 expression by sponging miR-208b-5p.

CONCLUSION

Circ_0001445 could abate ox-LDL-mediated HAEC damage by the miR-208b-5p/ABCG1 axis, providing a novel insight into the pathogenesis and treatment of CAD.

MicroRNAs-The Heart of Post-Myocardial Infarction Remodeling

Myocardial infarction (MI) is one of the most frequent cardiac emergencies, with significant potential for mortality. One of the major challenges of the post-MI healing response is that replacement fibrosis could lead to left ventricular remodeling (LVR) and heart failure (HF). This process involves canonical and non-canonical transforming growth factor-beta (TGF-β) signaling pathways translating into an intricate activation of cardiac fibroblasts and disproportionate collagen synthesis. Accumulating evidence has indicated that microRNAs (miRNAs) significantly contribute to the modulation of these signaling pathways. This review summarizes the recent updates regarding the molecular mechanisms underlying the role of the over 30 miRNAs involved in post-MI LVR. In addition, we compare the contradictory roles of several multifunctional miRNAs and highlight their potential use in pressure overload and ischemia-induced fibrosis. Finally, we discuss their attractive role as prognostic biomarkers for HF, highlighting the most relevant human trials involving these miRNAs.

MiR-208b Regulates Rabbit Preadipocyte Proliferation and Differentiation

microRNAs (miRNAs) play an important role in gene regulation in animals by pairing with target gene mRNA. Many miRNAs are differentially expressed in the adipose tissue, often with conserved expression. In our study, we found that miR-208b expression was observed differently in the preadipocyte differentiation model. When miR-208b was overexpressed in the preadipocyte differentiation model, the overexpressed group displayed higher expression of PPARγ and FABP4—the markers of preadipocyte differentiation. Oil Red O staining revealed that the count of lipid droplets was increased in the overexpressed group. When the expression of miR-208b was inhibited, the above indicators showed an opposite trend. Moreover, results from both 5-ethynyl-2′-deoxyuridine (EDU) and cell counting kit (CCK) analysis showed that miR-208b promoted the proliferation of preadipocyte. Expression of gene CSNK2A2, a direct miR-208b target, was downregulated in the overexpressed group, providing a possible link to multiple signal pathways. Overall, our data indicate that miR-208b play a positive regulatory effect on the proliferation and differentiation of rabbit preadipocyte.

Systematic review of microRNA biomarkers in acute coronary syndrome and stable coronary artery disease

The aim of this systematic review was to assess dysregulated miRNA biomarkers in coronary artery disease (CAD). Dysregulated microRNA (miRNAs) have been shown to be linked to cardiovascular pathologies including CAD and may have utility as diagnostic and prognostic biomarkers. We compared miRNAs identified in acute coronary syndrome (ACS) compared with stable CAD and control populations. We conducted a systematic search of controlled vocabulary and free text terms related to ACS, stable CAD and miRNA in Biosis Previews (OvidSP), The Cochrane Library (Wiley), Embase (OvidSP), Global Health (OvidSP), Medline (PubMed and OvidSP), Web of Science (Clarivate Analytics), and ClinicalTrials.gov which yielded 7370 articles. Of these, 140 original articles were appropriate for data extraction. The most frequently reported miRNAs in any CAD (miR-1, miR-133a, miR-208a/b, and miR-499) are expressed abundantly in the heart and play crucial roles in cardiac physiology. In studies comparing ACS cases with stable CAD patients, miR-21, miR-208a/b, miR-133a/b, miR-30 family, miR-19, and miR-20 were most frequently reported to be dysregulated in ACS. While a number of miRNAs feature consistently across studies in their expression in both ACS and stable CAD, when compared with controls, certain miRNAs were reported as biomarkers specifically in ACS (miR-499, miR-1, miR-133a/b, and miR-208a/b) and stable CAD (miR-215, miR-487a, and miR-502). Thus, miR-21, miR-133, and miR-499 appear to have the most potential as biomarkers to differentiate the diagnosis of ACS from stable CAD, especially miR-499 which showed a correlation between the level of their concentration gradient and myocardial damage. Although these miRNAs are potential diagnostic biomarkers, these findings should be interpreted with caution as the majority of studies conducted predefined candidate-driven assessments of a limited number of miRNAs (PROSPERO registration: CRD42017079744).

Difference in microRNA levels in the post-mortem blood from different sampling sites: A proof of concept

MicroRNAs have various characteristics, including stability, and tissue and disease specificity. One of the important issues in forensics is that biomarkers can differ quantitatively depending on the sampling site. We aimed at evaluating the differences in microRNA levels in the post-mortem (PM) blood from different sampling sites. The study subjects comprised seventeen males and eleven females. The number of cardiac deaths (CD) and non-cardiac deaths (NCD) was eleven and seventeen, respectively. A cardiopulmonary resuscitation (CPR) was performed in fifteen cases. Venous blood was obtained from the external iliac vein for peripheral blood (PB), inferior vena cava for pre-cardiac blood (CB), and coronary sinus for post-cardiac blood (coronary sinus blood, CSB). The selected target microRNAs were cardiac-specific (miR208 and miR-1) and non-cardiac microRNAs (miR-16 and let-7e). The levels of miR-208b and miR-1 in the PM blood differed according to its sampling site and showed an increasing order of tendency in the PB, CB, and CSB. However, these variations according to sampling sites did not correlate with the post-mortem interval and the levels did not differ between the CD and NCD groups, and between the CPR and non-CPR groups. MiR-16 and let-7e levels did not vary according to the sampling site. The present study confirms that the cardiac-specific microRNA levels in the PM blood from different sampling sites are different. In addition, this study showed that the characteristics of target microRNAs, such as tissue-specificity, should be considered and the sampling site for microRNAs should be presented in forensic applications.

Circulating miR-130 is a potential bio signature for early prognosis of acute myocardial infarction

Background

As distinctive leading reasons of death globally, acute myocardial infarction (AMI). Accounts for major death ratio, caused by coronary artery disease (CAD). Its diagnosis relies on the presenting clinical symptoms, electrocardiograms (ECGs), and levels of circulating biomarkers. Recent studies have implicated microRNAs (miRNAs) in the pathogenesis of many diseases, including AMI. The present study inquire into feature value of miR-130 in AMI patients.

Methods

levels of expression of miR-130 in patient plasma, considered through simultaneous quantitative polymerase chain reaction (qRT-PCR). The method used for determining Plasma cardiac troponin I (cTnI) & creatine kinase-MB(CK-MB) degree set on by enzyme-linked immunosorbent assay (ELISA). The diagnostic value of miR-130 was measured using a receiver operating characteristic (ROC) curve.

Results

Plasma miR-130, cTnI, and CK-MB levels exist remarkably inflated in the AMI classification in comparison with control category (P<0.05). MiR-130 expression peaked 6 hours after disease onset, earlier than cTnI and CK-MB. The level of expression of miR-130 6 hours after disease onset was positively correlated with cTnI and CK-MB levels 12 hours after onset. The optimal cut-off point for miR-130 in peripheral blood, sensitivity, and specificity were 1.58 ng/mL, 82.5% and 77.5%, respectively. The area under curve (AUC) was 0.922.

Conclusions

These results indicate that circulating miR-130 holds great promise as an effective biomarker for diagnosing AMI earlier.

MicroRNA-208a: a Good Diagnostic Marker and a Predictor of no-Reflow in STEMI Patients Undergoing Primary Percutaneuos Coronary Intervention

MicroRNA-208a is a cardiac specific oligo-nucleotide. We aimed at investigating the ability of microRNA-208a to diagnose myocardial infarction and predict the outcome of primary percutaneuos coronary angiography (PCI). Patients (n = 75) presented by chest pain were recruited into two groups. Group 1 (n = 40) had ST elevation myocardial infarction (STEMI) and underwent primary PCI: 21 patients had sufficient reperfusion and 19 had no-reflow. Group 2 (n = 35) had negative cardiac troponins (cTns). Plasma microRNA-208a expression was assessed using quantitative polymerase chain reaction and patients were followed for occurrence of in-hospital major adverse cardiac events (MACE). MicroRNA-208a could diagnose of MI (AUC of 0.926). After primary PCI, it was superior to cTnT in prediction of no-reflow (AUC difference of 0.231, P = 0.0233) and MACE (AUC difference of 0.367, P = 0.0053). Accordingly, circulating levels of miR-208a can be used as a diagnostic marker of MI and a predictor of no-reflow and in-hospital MACE. Graphical abstract Receiver operating curve analysis of no-reflow prediction of miRNA208a, CK-MB and hs-Troponin T. MicroRNA-208a shows significantly higher prediction of no-reflow as compared to routine cardiac biomarkers.

A systematic review of microRNAs in patients with hypertrophic cardiomyopathy

BACKGROUND

Several microRNAs (miRNA) have been associated with hypertrophic cardiomyopathy (HCM), but studies differ regarding methods employed. In an attempt to understand their role in the disease, we performed a systematic review of studies assessing miRNAs and their association with HCM.

METHODS

The literature search was based on The Medical Subject Headings (MeSH) terms "Hypertrophic Cardiomyopathy" and "MicroRNA" combined with other synonyms on Embase, Medline and LILACS databases in April 2020. The selected studies and data extraction were independently evaluated. Only human reports with a clear definition of HCM diagnosis were included.

RESULTS

The search found 68 studies, 13 fulfilled the selection criteria, with a total of 329 patients. Eighty-seven miRNA were differentially expressed in HCM patients, being mir-21, mir-29a and mir-133 the most reported. The miRNA were mainly up-regulated, where mir-29a was up-regulated in 6 studies, followed by mir-133 in 4 and mir-21 in 3. The other miRNAs were mainly up-regulated. Blood samples were evaluated in the majority of patients (86%), but a greater number of miRNAs (79%) were assessed in myocardium. Six studies evaluating the phenotype correlation demonstrated that several miRNAs, mainly mir-1-3p, mir-19b, mir-21, mir-29a, mir-155, and mir-221, were related to either hypertrophy or fibrosis. Mir-29a showed a more consistent phenotypic correlation.

CONCLUSION

Eighty-seven miRNAs were differentially expressed in HCM patients, the majority in up-regulation. Mir-21, mir-29a and mir-133 were the most reported. Correlation with left ventricular hypertrophy and fibrosis was evaluated in six studies for several miRNAs, nevertheless, mir-29a showed more consistent findings and seems to be a promising biomarker.

MicroRNA-363-3p serves as a diagnostic biomarker of acute myocardial infarction and regulates vascular endothelial injury by targeting KLF2

Background

Acute myocardial infarction (AMI) is a serious cardiovascular disease. This study aimed to investigate the diagnostic value of microRNA-363-3p (miR-363-3p) in AMI patients and explore the effects of miR-363-3p on vascular endothelial injury in an AMI rat model.

Methods

The Expression of miR-363-3p was measured by quantitative real-time PCR. A receiver operating characteristic (ROC) curve was plotted to evaluate the diagnostic value of miR-363-3p in AMI patients. The biomarkers of endothelial injury were estimated using enzyme-linked immunosorbent assays, and the correlation of miR-363-3p with these markers was assessed. AMI rat model was constructed using coronary artery ligation, and the effects of miR-363-3p on endothelial injury and endothelial cell proliferation were analyzed.

Results

Serum expression of miR-363-3p was upregulated in the AMI patients compared with healthy controls. The increased serum miR-363-3p serves a candidate diagnostic biomarker of AMI. The correlation analysis indicated that serum miR-363-3p expression was positively correlated with the concentration of endothelial injury biomarkers in AMI patients. Furthermore, the increased endothelial injury biomarkers in AMI rats were all inhibited by the knockdown of miR-363-3p, and the cell proliferation of human umbilical vein endothelial cells was obviously enhanced by the reduction of miR-363-3p. The prediction results shown that Kruppel-like factor 2 (KLF2) is a target of miR-363-3p, and their interaction was proved using a luciferase reporter assay.

Conclusions

Collectively, overexpression of miR-363-3p acts as a diagnostic biomarker for patients with AMI, and the downregulation of miR-363-3p improves AMI-associated endothelial injury by targeting KLF2, which indicated that miR-363-3p has a potential to develop the treatment of AMI.

Noncoding RNAs as Biomarkers for Acute Coronary Syndrome

Acute coronary syndrome (ACS), consisting of acute myocardial infarction and unstable angina, is the most dangerous and fatal form of coronary heart disease. Acute coronary syndrome has sudden onset and rapid development, which may lead to malignant life-threatening conditions at any time. Therefore, early detection and diagnosis are critical for patients with ACS. Recent studies have found that noncoding RNA is of great significance in the diagnosis and treatment of cardiovascular diseases. In this review, we summarized recent data on circulating noncoding RNAs (including microRNA, long noncoding RNA, and circular RNA) as diagnostic and prognostic markers in ACS including acute myocardial infarction and unstable angina. Specifically, microRNAs (miRNAs) as diagnostic markers are divided into three types: miRNAs of increased expression in ACS, miRNAs of decreased expression in ACS, and miRNAs of contradictory expression in ACS. Moreover, we described these miRNAs of increased expression in ACS based on miRNAs family. This review may result in a great guidance of noncoding RNAs as biomarkers for ACS in clinical practice.

Silence of miR-32-5p promotes endothelial cell viability by targeting KLF2 and serves as a diagnostic biomarker of acute myocardial infarction

Background

MicroRNAs (miRNAs) have been investigated in various cardiovascular diseases. As a fatal disease, acute myocardial infarction (AMI) is a serious global health burden. The purpose of this study was to investigate the role of miR-32-5p in AMI patients and human umbilical vein endothelial cells (HUVECs) to explore novel diagnostic and therapeutic approaches for AMI.

Methods

A target prediction tool miRanda and the luciferase activity assay were used to confirm the interaction of miR-32-5p with Kruppel-like factor 2 (KLF2). Effect of miR-32-5p on HUVECs viability was examined using CCK-8 assay. Serum miR-32-5p expression was measured using quantitative Real-Time PCR, and its correlation with myocardial damage and endothelial injury markers and pro-inflammatory cytokines was assessed. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic value of miR-32-5p in AMI patients.

Results

miR-32-5p, as a direct regulator of KLF2, could suppress the cell proliferation of HUVECs. Serum miR-32-5p expression was elevated in AMI patients and positively correlated with the biomarker levels of myocardial damage and endothelial injury and pro-inflammatory cytokines. The area under the ROC curve for miR-32-5p was 0.949, indicating the relatively high diagnostic accuracy of miR-32-5p in AMI patients.

Conclusion

The data of this study revealed that the increased serum miR-32-5p expression serves as a candidate diagnostic biomarker of AMI, and that miR-32-5p may be involved in the myocardial damage, endothelial injury and inflammatory responses of AMI by targeting KLF2, indicating the potential of miR-32-5p as a diagnostic biomarker and molecular target to improve the treatment of AMI.

miRNAs as Biomarkers in Disease: Latest Findings Regarding Their Role in Diagnosis and Prognosis

MicroRNAs (miRNAs) represent a class of small, non-coding RNAs with the main roles of regulating mRNA through its degradation and adjusting protein levels. In recent years, extraordinary progress has been made in terms of identifying the origin and exact functions of miRNA, focusing on their potential use in both the research and the clinical field. This review aims at improving the current understanding of these molecules and their applicability in the medical field. A thorough analysis of the literature consulting resources available in online databases such as NCBI, PubMed, Medline, ScienceDirect, and UpToDate was performed. There is promising evidence that in spite of the lack of standardized protocols regarding the use of miRNAs in current clinical practice, they constitute a reliable tool for future use. These molecules meet most of the required criteria for being an ideal biomarker, such as accessibility, high specificity, and sensitivity. Despite present limitations, miRNAs as biomarkers for various conditions remain an impressive research field. As current techniques evolve, we anticipate that miRNAs will become a routine approach in the development of personalized patient profiles, thus permitting more specific therapeutic interventions.

MicroRNAs as Prognostic Markers in Acute Coronary Syndrome Patients-A Systematic Review

Background: The potential utility of microRNAs (miRNAs) in the diagnosis, prognosis, and treatment of multiple disease states has been an area of great interest since their discovery. In patients with cardiovascular disease, there is a large pool of literature amassed from the last decade assessing their diagnostic and prognostic potential. This systematic review sought to determine whether existing literature supports the use of miRNAs as prognostic markers after an Acute Coronary Syndrome (ACS) presentation. Methods: A systematic review of published articles from 2005–2019 using MEDLINE and EMBASE databases was undertaken independently by two reviewers. Studies addressing prognosis in an ACS population yielded 32 studies and 2 systematic reviews. Results/conclusion: 23 prospective studies reported significant differences in miRNA levels and 16 compared the predictive power of miRNAs. The most common miRNAs assessed included miR-133a, -208b, -21, -1, -34a, -150, and -423, shown to be involved in cell differentiation, apoptosis, and angiogenesis. Barriers to the use of miRNAs as prognostic markers include bias in miRNA selection, small sample size, variable normalization of data, and adjustment for confounders. Therefore, findings from this systematic review do not support the use of miRNAs for prognostication post-ACS beyond traditional cardiovascular risk factors, existing risk scores, and stratifications tools.

Epigenetic Biomarkers in Cardiovascular Diseases

Cardiovascular diseases are the number one cause of death worldwide and greatly impact quality of life and medical costs. Enormous effort has been made in research to obtain new tools for efficient and quick diagnosis and predicting the prognosis of these diseases. Discoveries of epigenetic mechanisms have related several pathologies, including cardiovascular diseases, to epigenetic dysregulation. This has implications on disease progression and is the basis for new preventive strategies. Advances in methodology and big data analysis have identified novel mechanisms and targets involved in numerous diseases, allowing more individualized epigenetic maps for personalized diagnosis and treatment. This paves the way for what is called pharmacoepigenetics, which predicts the drug response and develops a tailored therapy based on differences in the epigenetic basis of each patient. Similarly, epigenetic biomarkers have emerged as a promising instrument for the consistent diagnosis and prognosis of cardiovascular diseases. Their good accessibility and feasible methods of detection make them suitable for use in clinical practice. However, multicenter studies with a large sample population are required to determine with certainty which epigenetic biomarkers are reliable for clinical routine. Therefore, this review focuses on current discoveries regarding epigenetic biomarkers and its controversy aiming to improve the diagnosis, prognosis, and therapy in cardiovascular patients.

miR-130 aggravates acute myocardial infarction-induced myocardial injury by targeting PPAR-γ

Cardiac remodeling is a common pathophysiological change associated with acute myocardial infarction (AMI). Recent evidence indicates that microRNAs are strong posttranscriptional regulators which play an important role in regulating the microenvironment of myocardial tissue after AMI. In this study, we sought to explore the potential role and underlying mechanism of miR-130 in AMI. H9c2 cells were cultured under hypoxic conditions to simulate myocardial infarction. The influence of aberrantly expressed miR-130 on H9c2 cells under hypoxia was also estimated with RT-PCR, western blot and enzyme-linked immunosorbent assay. Using bioinformatics methods, of miR-130 target genes were verified with luciferase reporter assay. Then, the effects of miR-130 on AMI were identified in an induced myocardial injury model in rats. The results show that miR-130 downregulation remarkably decreased hypoxia-induced inflammation and fibrosis related protein expression in H9c2 cells and reversed hypoxia-induced peroxisome proliferator-activated receptor γ (PPAR-γ) inhibition. A bifluorescein reporter assay further confirmed that PPAR-γ was a target gene of miR-130. This study verified that PPAR-γ has a cardioprotective effect by inhibiting NFκB-mediated inflammation and TGF-β1-mediated fibrosis. In vivo experiments confirmed that downregulation of miR-130 expression promotes PPAR-γ-mediated cardioprotective effects by suppressing inflammation and myocardial fibrosis. Taken together, these findings suggest that miR-130 knockdown alleviates infarction-induced myocardial injury by promoting PPAR-γ expression.

Expression Profiles of Six Atherosclerosis-Associated microRNAs That Cluster in Patients with Hyperhomocysteinemia: A Clinical Study

The aim of this study is to discuss the hypothesis that expression of plasma atherosclerosis-associated microRNAs (miRNAs) in hyperhomocysteinemia (Hhcy) patients could predict the presence of atherosclerosis from different channels. Six plasma miRNAs (miR-145, miR-155, miR-222, miR-133, miR-217, and miR-30) selected for our study have been confirmed as critical gene regulators involved in atherosclerosis and can be steadily determined in plasma. Expression of the above six plasma circulating miRNAs revealed significant upregulation of two miRNAs (miR-133 and miR-217) and downregulation of three miRNAs (miR-145, miR-155, and miR-222). Six candidate miRNAs showed a significant correlation with homocysteine (Hcy) or lipid parameters. The results of this study indicated that miR-217 was further significantly upregulated in Hhcy + ATH groups than in normal control, Hhcy-, and atherosclerosis-alone (ATH) groups and it showed a significant negative correlation with Hcy and triglycerides. More specifically, miR-217 showed the most specific expression patterns in all patients with atherosclerosis (ATH and Hhcy + ATH groups), which may have been a diagnostic value for Hhcy complicated with atherosclerosis, and predicted the progress of atherosclerosis in Hhcy patients effectively.

Pathophysiology of cardiovascular disease in diabetes mellitus

Diabetes mellitus elicits cellular, epigenetic, and post-translational changes that directly or indirectly affect the biology of the vasculature and other metabolic systems resulting in the apparition of cardiovascular disease. In this review, we provide a current perspective on the most recent discoveries in this field, with particular focus on hyperglycemia- induced pathology in the cardiovascular system. We also provide perspective on the clinical importance of molecular targeting of cardiovascular and diabetes mellitus therapies to treat hyperglycemia, inflammation, thrombosis, dyslipidemia, atherosclerosis, and hypertension.

MiRroring the Multiple Potentials of MicroRNAs in Acute Myocardial Infarction

At present, cardiovascular diseases are depicted to be the leading cause of death worldwide according to the World Health Organization. In the future, projections predict that ischemic heart disease will persist in the top main causes of illness. Within this alarming context, some tiny master regulators of gene expression programs, namely, microRNAs (miRNAs) carry three promising potentials. In fact, miRNAs can prove to be useful not only in terms of biomarkers allowing heart injury detection but also in terms of therapeutics to overcome limitations of past strategies and treat the lesions. In a more creative approach, they can even be used in the area of human engineered cardiac tissues as maturation tools for cardiomyocytes (CMs) derived from pluripotent stem cell. Very promising not only for patient-specific cell-based therapies but also to develop biomimetic microsystems for disease modeling and drug screening, these cells greatly contribute to personalized medicine. To get into the heart of the matter, the focus of this review lies primarily on miRNAs as acute myocardial infarction (AMI) biomarkers. Only large cohort studies comprising over 100 individuals to reach a potent statistical value were considered. Certain miRNAs appeared to possibly complement protein-based biomarkers and classical risk factors. Some were even described to bear potential in the discrimination of similar symptomatic pathologies. However, differences between pre-analytical and analytical approaches substantially influenced miRNA data. Further supported by meta-analysis studies, this problem had to be addressed. A detailed critical analysis of each step to define miRNAs biomarker potential is provided to inspire a future improved universal strategy. Interestingly, a recurrent set of cardiomyocyte-enriched miRNAs was found, namely, miR-1; miR-133; miR-208a/b; and miR-499a. Each member of this myomiRs group displayed promising roles either individually or in combination as AMI diagnostic or prognostic biomarkers. Furthermore, a precise combo was shown to be powerful enough to transdifferentiate human fibroblasts into CMs opening doors in the therapeutics. Following these discoveries, they also emerged as optional tools to transfect in order to mature CMs derived from pluripotent stem cells. Ultimately, the multiple potentials carried by the myomiRs miR-1; miR-133; miR-208a/b; and miR-499a still remain to be fully unveiled.