MiRNAs as biomarkers for diagnosis of neonatal sepsis: a systematic review and meta-analysis

BACKGROUND

The relationship between circulating miRNAs and neonatal sepsis and the mechanism of action are still unclear at this time. Therefore, the potential diagnostic role of miRNAs in neonatal sepsis (NS) was studied through meta-analysis.

METHOD

Web of Science, Cochrane Library, PubMed, and Embase are retrieved, supplemented by manual search, and the search was conducted to find related studies without time limit until May 2022.The quality of the literature was assessed via QUADAS criteria and meta-analyzed via Stata 11.0 software, including the assessment of specificity, sensitivity, likelihood ratio and diagnostic odds ratio. Then, sensitivity analysis and heterogeneity testing were conducted, and finally, the summary receiver operating characteristics (SROC) curve was drawn.

RESULT

This study included 14 articles, including 20 miRNAs and 1597 newborns(control group: 727 and case group: 870). Among them, one article was of low quality, three articles were of high quality, and the rest were of medium quality. According to the results of random effects model analysis, the pooled specificity and sensitivity of miRNA for the diagnosis of NS were 0.83 (95%CI: 0.79-0.87) and 0.76 (95%CI: 0.72-0.80), respectively. And negative likelihood ratio, positive likelihood ratio, and diagnostic odds ratio were 0.29 (95%CI: 0.24-0.34), 4.51 (95%CI: 3.52-5.78), and 15.81 (95%CI: 10.71-23.35), respectively. The area under the SROC curve was 0.86, and there was no evidence publication bias detected in the funnel plot.

CONCLUSION

Circulating miRNAs may be very useful in the development of early diagnostic strategies for neonatal sepsis.

miR-21 in Human Cardiomyopathies

miR-21 is a 22-nucleotide long microRNA that matches target mRNAs in a complementary base pairing fashion and regulates gene expression by repressing or degrading target mRNAs. miR-21 is involved in various cardiomyopathies, including heart failure, dilated cardiomyopathy, myocardial infarction, and diabetic cardiomyopathy. Expression levels of miR-21 notably change in both heart and circulation and provide cardiac protection after heart injury. In the meantime, miR-21 also tightly links to cardiac dysfunctions such as cardiac hypertrophy and fibrosis. This review focuses on the miR-21 expression pattern and its functions in diseased-heart and further discusses the feasibility of miR-21 as a biomarker and therapeutic target in cardiomyopathies.

The Diagnostic Value of Plasma miRNA-497, cTnI, FABP3 and GPBB in Pediatric Sepsis Complicated with Myocardial Injury

Objective

To investigate the diagnostic value of plasma miRNA-497, cardiac troponin I (cTnI), fatty acid binding protein 3 (FABP3), glycogen phosphorylase isoenzyme BB (GPBB) in pediatric sepsis complicated with myocardial injury.

Methods

From August 2018 to February 2020, 82 children with sepsis admitted to our hospital and 50 health children who came for physical examination (defined as control group) were enrolled in this study. Children with sepsis and myocardial injury were enrolled in the combined group (n=35), and those without myocardial injury were enrolled in the sepsis group (n=47). General data of three groups were collected, and the levels of miRNA-497, FABP3, GPBB, creatine kinase isoenzyme MB (CK-MB), procalcitonin (PCT), C-reactive protein (CRP), cTnI and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were detected and the cardiac function was measured. The diagnostic value of plasma miRNA-497, cTnI, FABP3 and GPBB in pediatric sepsis complicated with myocardial injury was analyzed.

Results

The infection site of the combined group was not significantly different from that of the sepsis group. The levels of miRNA-497, FABP3, GPBB, CK-MB, PCT, CRP, cTnI, NT-proBNP in the combined group were all higher than those in the sepsis group and the control group (P<0.05), and the left ventricular ejection fraction (LVEF) in the combined group was significantly lower than that in the other two group (P<0.05). The area under the curve (AUC) of the combination of miRNA-497, FABP3, GPBB, and cTnI in the diagnosis of sepsis complicated with myocardial injury was significantly higher than that of CK-MB, PCT, CRP, NT-proBNP alone (P<0.05), but there was no significant difference when compared with miRNA-497, FABP3, GPBB and cTnI alone (P>0.05). When the optimal thresholds of miRNA-497, FABP3, GPBB, and cTnI were set to 2.03, 6.23ng/mL, 4.01ng/mL, 1.23ng/mL, respectively, the sensitivity was 95.65%, 88.89%, 82.61%, 87.50%, respectively; the specificity was 83.33%, 94.12%, 83.33%, 90.91%, respectively; and the accuracy was 91.43%, 91.43%, 82.86%, 88.57%, respectively. Pearson correlation analysis indicating that miRNA-497 was positively correlated with the levels of FABP3, GPBB, and cTnI in the combined group (r=0.821, 0.621, 0.782, P<0.05).

Conclusion

Plasma miRNA-497, cTnI, FABP3, and GPBB levels were increased in pediatric sepsis complicated with myocardial injury, and their combination had high diagnostic value, which was of great clinical significance for early diagnosis and early treatment of pediatric sepsis complicated with myocardial injury.

The impact of exogenous nitric oxide during cardiopulmonary bypass for cardiac surgery

OBJECTIVES

Cardiac surgery using cardiopulmonary bypass frequently provokes a systemic inflammatory response syndrome. This can lead to the development of low cardiac output syndrome (LCOS). Both of these can affect morbidity and mortality. This study is a systematic review of the impact of gaseous nitric oxide (gNO), delivered via the cardiopulmonary bypass (CPB) circuit during cardiac surgery, on post-operative outcomes. It aims to summarise the evidence available, to assess the effectiveness of gNO via the CPB circuit on outcomes, and highlight areas of further research needed to develop this hypothesis.

METHODS

A comprehensive search of Pubmed, Embase, Web of Science and the Cochrane Library was performed in May 2020. Only randomised control trials (RCTs) were considered.

RESULTS

Three studies were identified with a total of 274 patients. There was variation in the outcomes measures used across the studies. These studies demonstrate there is evidence that this intervention may contribute towards cardioprotection. Significant reductions in cardiac troponin I (cTnI) levels and lower vasoactive inotrope scores were seen in intervention groups. A high degree of heterogeneity between the studies exists. Meta-analysis of the duration of mechanical ventilation, length of ICU stay and length of hospital stay showed no significant differences.

CONCLUSION

This systematic review explored the findings of three pilot RCTs. Overall the hypothesis that NO delivered via the CPB circuit can provide cardioprotection has been supported by this study. There remains a significant gap in the evidence, further high-quality research is required in both the adult and paediatric populations.

Advances in Cardiovascular Biomarker Discovery

Cardiovascular diseases are the leading causes of mortality worldwide. Among them, hypertension and its pathological complications pose a major risk for the development of other cardiovascular diseases, including heart failure and stroke. Identifying novel and early stage biomarkers of hypertension and other cardiovascular diseases is of paramount importance in predicting and preventing the major morbidity and mortality associated with these diseases. Biomarkers of such diseases or predisposition to their development are identified by changes in a specific indicator’s expression between healthy individuals and patients. These include changes in protein and microRNA (miRNA) levels. Protein profiling using mass spectrometry and miRNA screening utilizing microarray and sequencing have facilitated the discovery of proteins and miRNA as biomarker candidates. In this review, we summarized some of the different, promising early stage protein and miRNA biomarker candidates as well as the currently used biomarkers for hypertension and other cardiovascular diseases. Although a number of promising markers have been identified, it is unlikely that a single biomarker will unambiguously aid in the classification of these diseases. A multi-marker panel-strategy appears useful and promising for classifying and refining risk stratification among patients with cardiovascular disease.

MicroRNAs as potential biomarkers in congenital heart surgery

OBJECTIVE

Pediatric congenital heart surgery (CHS) involves intracardiac, valvular, and vascular repairs. Accurate tools to aid short-term outcome prediction in pediatric CHS are lacking. Clinical scores, such as the vasoactive-inotrope score and ventilation index, are used to define outcome in clinical studies. MicroRNA-1-3p (miR-1) is expressed by both cardiomyocytes and vascular cells and is regulated by hypoxia. In adult patients, miR-1 increases in the circulation after open-heart cardiac surgery, suggesting its potential as a clinical biomarker. Thus, we investigated whether perioperative circulating miR-1 measurements can help predict post-CHS short-term outcomes in pediatric patients.

METHODS

Plasma miR-1 was retrospectively measured in a cohort of 199 consecutive pediatric CHS patients (median age 1.2 years). Samples were taken before surgery and at the end of the operation. Plasma miR-1 concentration was measured by reverse transcription-quantitative polymerase chain reaction and expressed as miR-1 copies/μL and as relative expression to spiked-in exogenous cel-miR-39.

RESULTS

Baseline plasma miR-1 did not vary across different diagnoses, increased during surgery (204-fold median relative increase, P < .001), and was associated with aortic crossclamp duration postoperatively (P < .001). Importantly, miR-1 levels at the end of the operation positively correlated with intensive care stay (P < .001), early severe cardiovascular events (P = .01), and with high vasoactive-inotrope score (P = .001) and ventilation index (P < .001), suggesting that miR-1 could accelerate the identification of patients with cardiopulmonary bypass-related ischemic complications, requiring more intensive support.

CONCLUSIONS

Our study suggests miR-1 as a novel potential circulating biomarker to predict early postoperative outcome and inform clinical management in pediatric heart surgery.

Plasma Levels of Myocardial MicroRNA-133a Increase by Intraoperative Cytokine Hemoadsorption in the Complex Cardiovascular Operation

Background

Complex cardiovascular procedures may initiate a systemic inflammatory response syndrome (SIRS) with a massive cytokine release, which is involved in postoperative myocardial injury. Intraoperative cytokine hemoadsorption (HA) mitigates the inflammatory response. Micro ribonucleic acids (miRNAs) are emerging as a marker of myocardial injury.

Methods

This study evaluated if intraoperative cytokine reduction by HA modulates SIRS and affects myocardial injury as measured by miRNA-126, 223 and miRNA-1, 133a, respectively. Twenty-eight patients were assigned into HA (n = 15) and control (C) (n = 13) groups. HA was performed by integrating CytoSorb™ into the extracorporeal circuit.

Results

MiRNA-133a plasma levels were increased postoperatively in both groups but were much higher in the HA group than in the C group at 3 h (P = 0.037) and 18 h (P = 0.017) after reperfusion. MiRNA-1 and miRNA-223 plasma levels were significantly increased postoperatively, but did not differ between groups. The vascular miRNA-126 was not affected.

Conclusion

Intraoperative cytokine HA in cardiovascular operations increased the plasma levels of miRNA-133a, suggesting higher myocardial injury.

Identification of microRNAs related to myocardial ischemic reperfusion injury

Previous studies have suggested that microRNAs (miRNAs) are associated with the progression of myocardial ischemic reperfusion (I/R) injury. However, inconsistent results have been obtained due to the differences in sequencing platform, control selection, and filtering conditions. To explore the key miRNAs in the pathogenesis of myocardial I/R injury and develop miRNA diagnostic biomarkers for myocardial I/R injury prevention, we performed a systematic analysis of publicly available myocardial I/R injury miRNA expression data and investigated the function of the signature miRNA. A total of 17 representative myocardial I/R injury miRNA datasets were extracted from the Google Scholar website and a systematic bioinformatics analysis was done. TargetScan software was used to predict the miRNA target genes, and functional enrichment and transcription factor binding analyses were performed on the target genes using the DAVID and Tfacts databases. In this study, a total of 10 signature miRNAs associated with myocardial I/R injury were identified, which included eight significantly upregulated miRNAs (miR-let-7b-3p, miR-let-7c-3p, miR-15b-3p, miR-195-3p, miR-21-5p, miR-214-5p, miR-24-3p, and miR-320a) and two significantly downregulated miRNAs (miR-126-5p and miR-499a-5p). They had different influences on myocardial I/R injury. The upregulated target gene-expressing signature messenger RNAs (mRNAs) were mainly involved in the transcriptional regulation process of GO: 0000122, negative regulation of transcription from RNA polymerase II promoter, and so on, while downregulated expression of signature mRNAs was mainly involved in GO:0070534, protein K63-linked ubiquitination, and so forth. To summarize, 10 signature miRNAs of myocardial I/R injury pathogenesis were identified and their target genes and transcription factors were revealed, suggesting the potential novel therapeutic targets for myocardial I/R injury.

Chip-based digital PCR as a novel detection method for quantifying microRNAs in acute myocardial infarction patients

miRNAs have shown promise as potential biomarkers for acute myocardial infarction (AMI). However, the current used quantitative real-time PCR (qRT-PCR) allows solely for relative expression of nucleic acids and it is susceptible to day-to-day variability, which has limited the validity of using the miRNAs as biomarkers. In this study we explored the technical qualities and diagnostic potential of a new technique, chip-based digital PCR, in quantifying the miRNAs in patients with AMI and ischaemia-reperfusion injury (I/R). In a dilution series of synthetic C.elegans-miR-39, chip-based digital PCR displayed a lower coefficient of variation (8.9% vs 46.3%) and a lower limit of detection (0.2 copies/μL vs 1.1 copies/μL) compared with qRT-PCR. In the serum collected from 24 patients with ST-elevation myocardial infarction (STEMI) and 20 patients with stable coronary artery disease (CAD) patients after percutaneous coronary intervention (PCI), we used qRT-PCR and multiplexed chip-based digital PCR to quantify the serum levels of miRNA-21 and miRNA-499 as they have been validated in AMI in prior studies. In STEMI, I/R injury was assessed via measurement of ST-segment resolution (ST-R). Chip-based digital PCR revealed a statistical significance in the difference of miR-21 levels between stable CAD and STEMI groups (118.8 copies/μL vs 59 copies/μL; P=0.0300), whereas qRT-PCR was unable to reach significance (136.4 copies/μL vs 122.8 copies/μL; P=0.2273). For miR-499 levels, both chip-based digital PCR and qRT-PCR revealed statistically significant differences between stable CAD and STEMI groups (2 copies/μL vs 8.5 copies/μL, P=0.0011; 0 copies/μL vs 19.4 copies/μL; P<0.0001). There was no association between miR-21/499 levels and ST-R post-PCI. Our results show that the chip-based digital PCR exhibits superior technical qualities and promises to be a superior method for quantifying miRNA levels in the circulation, which may become a more accurate and reproducible method for directly quantifying miRNAs, particularly for use in large multi-centre clinical trials.

[Expression of plasma miRNA-497 in children with sepsis-induced myocardial injury and its clinical significance]

OBJECTIVE

To study the expression of plasma miRNA-497 in children with sepsis-induced myocardial injury and its clinical significance.

METHODS

A total of 148 children with sepsis were enrolled. According to the presence or absence of myocardial injury, these children were divided into myocardial injury group (n=58) and non-myocardial injury group (n=90). The two groups were compared in terms of the changes in plasma levels of miRNA-497, cardiac troponin I (cTnI), creatine kinase-MB (CK-MB), N-terminal pro-brain natriuretic peptide (NT-proBNP), procalcitonin (PCT), and C-reactive protein (CRP) and left ventricular ejection fraction (LVEF). The receiver operating characteristic (ROC) curve was plotted to evaluate the value of plasma miRNA-497, cTnI, and CK-MB in the diagnosis of myocardial injury. A Pearson correlation analysis was used to determine the correlation of miRNA-497 with cTnI, CK-MB, NT-proBNP, PCT, CRP, and LVEF.

RESULTS

Compared with the non-myocardial injury group, the myocardial injury group had significantly higher plasma levels of miRNA-497, cTnI, CK-MB, NT-proBNP, PCT, and CRP (P<0.05). Plasma miRNA-497, cTnI, and CK-MB when measured alone or in combination had an area under the ROC curve of 0.918, 0.931, 0.775, and 0.940 respectively. At the optimal cut-off value of 2.05, miRNA-497 had a sensitivity of 90.4% and a specificity of 91.2%. The correlation analysis showed that there was a good correlation between plasma miRNA-497 and cTnI in children with myocardial injury (r=0.728, P<0.01).

CONCLUSIONS

Plasma miRNA-497 has a similar value as cTnI in the diagnosis of sepsis-induced myocardial injury in children and may be used as a potential marker for early diagnosis of myocardial injury.

Epigenetic mechanisms in coronary artery disease: The current state and prospects

Coronary artery disease (CAD) is the leading cause of morbidity and mortality. CAD has both genetic and environmental causes. In the past two decades, the understanding of epigenetics has advanced swiftly and vigorously. It has been demonstrated that epigenetic modifications are associated with the onset and progression of CAD. This review aims to improve the understanding of the epigenetic mechanisms closely related to CAD and to provide a novel perspective on the onset and development of CAD. Epigenetic changes include DNA methylation, histone modification, microRNA and lncRNA, which are interrelated with critical genes and influence the expression of those genes. In addition, miRNA plays a diverse role in the pathological process of CAD. Numerous studies have found that some cardiac-specific miRNAs have potential as certain diagnostic biomarkers and treatment targets for CAD. In this review, the aberrant epigenetic mechanisms that contribute to CAD will be discussed. We will also provide novel insight into the epigenetic mechanisms that target CAD.

Noncoding RNAs in Heart Failure

Heart failure is a major contributor to the healthcare burden and mortality worldwide. Current treatment strategies are able to slow down the transition of healthy heart into the failing one; nevertheless better understanding of the complex genetic regulation of maladaptive remodeling in the failing heart is essential for new drug discovery. Noncoding RNAs are key epigenetic regulators of cardiac gene expression and thus significantly influence cardiac homeostasis and functions.In this chapter we will discuss characteristics of noncoding RNAs, especially miRNAs, long noncoding RNAs, and circular RNAs, and review recent evidences proving their profound involvement during different stages of heart failure progression. Several open questions still prevent the extensive use of noncoding RNA-modulating therapies in clinics; yet they are becoming an attractive target to define novel regulatory mechanisms in the heart. In-depth study of their interaction with gene networks will refine our current view of heart failure and revolutionize the drug development in coming years.

Non-coding RNAs in Development and Disease: Background, Mechanisms, and Therapeutic Approaches

Advances in RNA-sequencing techniques have led to the discovery of thousands of non-coding transcripts with unknown function. There are several types of non-coding linear RNAs such as microRNAs (miRNA) and long non-coding RNAs (lncRNA), as well as circular RNAs (circRNA) consisting of a closed continuous loop. This review guides the reader through important aspects of non-coding RNA biology. This includes their biogenesis, mode of actions, physiological function, as well as their role in the disease context (such as in cancer or the cardiovascular system). We specifically focus on non-coding RNAs as potential therapeutic targets and diagnostic biomarkers.

Modulating microRNAs in cardiac surgery patients: Novel therapeutic opportunities?

This review focuses on microRNAs (miRs) in cardiac surgery, where they are emerging as potential targets for therapeutic intervention as well as novel clinical biomarkers. Identification of the up/down-regulation of specific miRs in defined groups of cardiac surgery patients can lead to the development of novel strategies for targeted treatment in order to maximise therapeutic results and minimise acute, delayed or chronic complications. MiRs could also be involved in determining the outcome independently of complications, for example in relation to myocardial perfusion and fibrosis. Because of their relevance in disease, their known sequence and pharmacological properties, miRs are attractive candidates for therapeutic manipulation. Pharmacological inhibition of individual miRs can be achieved by modified antisense oligonucleotides, referred to as antimiRs, while miR replacement can be achieved by miR mimics to increase the level of a specific miR. MiR mimics can restore the function of a lost or down-regulated miR, while antimiRs can inhibit the levels of disease-driving or aberrantly expressed miRs, thus de-repressing the expression of mRNAs targeted by the miR. The main delivery methods for miR therapeutics involve lipid-based vehicles, viral systems, cationic polymers, and intravenous or local injection of an antagomiR. Local delivery is particularly desirable for miR therapeutics and options include the development of devices specific for local delivery, light-induced antimiR, and vesicle-encapsulated miRs serving as therapeutic delivery agents able to improve intracellular uptake. Here, we discuss the potential therapeutic use of miRNAs in the context of cardiac surgery.

microRNA-22 attenuates myocardial ischemia-reperfusion injury via an anti-inflammatory mechanism in rats

Previous studies have reported that microRNA-22 (miR-22) may be implicated in ischemia-reperfusion (I/R)-induced myocardial injury. Our previously published data also demonstrated that miR-22 may protect against myocardial I/R injury via anti-apoptosis in rats by targeting cAMP response element-binding protein binding protein (CBP). However, the specific function of miR-22 in myocardial I/R injury is far from fully elucidated. The present study was designed to investigate another cardioprotective signaling mechanism of miR-22 in myocardial I/R injury. A total of 40 adult male Sprague-Dawley rats were randomly divided into four equal groups (n=10): Sham, myocardial I/R, myocardial I/R with adenovirus expressing scramble miRNA (Ad-Scramble) and myocardial I/R with adenovirus expressing miR-22 (Ad-miR-22) groups. Besides the Sham operation group, the remaining three groups were artificially afflicted with coronary occlusion for 30 min and subsequently reperfused for 4 h. A light microscope was used to observe structural changes in the myocardium; reverse transcription polymerase chain reaction was used to measure the miR-22 mRNA expression level; the myocardial infarct size was analyzed by the Evans Blue/triphenyltetrazolium chloride double-staining; and p38 mitogen-activated protein kinase (MAPK), CBP, c-Jun-activator protein (AP)-1 and phospho (p)-c-Jun-AP-1 expression protein levels were detected by a western blot. Furthermore, ELISA was used to measure the levels of TNF-α and IL-6 in the myocardium. The results demonstrated that adenovirus-mediated miR-22 overexpression markedly reduced p38 MAPK, CBP, c-Jun-AP-1, p-c-Jun-AP-1 expression levels concomitant with an improvement in myocardial injury, including smaller infarct size, reduced release of creatine kinase, lactate dehydrogenase and proinflammation mediators (tumor necrosis factor-α and interleukin-6). These findings suggest that miR-22 has a protective effect on myocardial I/R injury. This protection mechanism, at least in part, is due to its anti-inflammatory function via the suppression of the p38 MAPK/CBP/c-Jun-AP-1 signaling pathway.

Coronary Artery-Bypass-Graft Surgery Increases the Plasma Concentration of Exosomes Carrying a Cargo of Cardiac MicroRNAs: An Example of Exosome Trafficking Out of the Human Heart with Potential for Cardiac Biomarker Discovery

Introduction

Exosome nanoparticles carry a composite cargo, including microRNAs (miRs). Cultured cardiovascular cells release miR-containing exosomes. The exosomal trafficking of miRNAs from the heart is largely unexplored. Working on clinical samples from coronary-artery by-pass graft (CABG) surgery, we investigated if: 1) exosomes containing cardiac miRs and hence putatively released by cardiac cells increase in the circulation after surgery; 2) circulating exosomes and exosomal cardiac miRs correlate with cardiac troponin (cTn), the current “gold standard” surrogate biomarker of myocardial damage.

Methods and Results

The concentration of exosome-sized nanoparticles was determined in serial plasma samples. Cardiac-expressed (miR-1, miR-24, miR-133a/b, miR-208a/b, miR-210), non-cardiovascular (miR-122) and quality control miRs were measured in whole plasma and in plasma exosomes. Linear regression analyses were employed to establish the extent to which the circulating individual miRs, exosomes and exosomal cardiac miR correlated with cTn-I. Cardiac-expressed miRs and the nanoparticle number increased in the plasma on completion of surgery for up to 48 hours. The exosomal concentration of cardiac miRs also increased after CABG. Cardiac miRs in the whole plasma did not correlate significantly with cTn-I. By contrast cTn-I was positively correlated with the plasma exosome level and the exosomal cardiac miRs.

Conclusions

The plasma concentrations of exosomes and their cargo of cardiac miRs increased in patients undergoing CABG and were positively correlated with hs-cTnI. These data provide evidence that CABG induces the trafficking of exosomes from the heart to the peripheral circulation. Future studies are necessary to investigate the potential of circulating exosomes as clinical biomarkers in cardiac patients.