Circulating microRNAs as biomarkers for myocardial fibrosis in patients with left ventricular non-compaction cardiomyopathy

Role of miRNA in Cardiovascular Diseases in Children-Systematic Review

The number of children suffering from cardiovascular diseases (CVDs) is rising globally. Therefore, there is an urgent need to acquire a better understanding of the genetic factors and molecular mechanisms related to the pathogenesis of CVDs in order to develop new prevention and treatment strategies for the future. MicroRNAs (miRNAs) constitute a class of small non-coding RNA fragments that range from 17 to 25 nucleotides in length and play an essential role in regulating gene expression, controlling an abundance of biological aspects of cell life, such as proliferation, differentiation, and apoptosis, thus affecting immune response, stem cell growth, ageing and haematopoiesis. In recent years, the concept of miRNAs as diagnostic markers allowing discrimination between healthy individuals and those affected by CVDs entered the purview of academic debate. In this review, we aimed to systematise available information regarding miRNAs associated with arrhythmias, cardiomyopathies, myocarditis and congenital heart diseases in children. We focused on the targeted genes and metabolic pathways influenced by those particular miRNAs, and finally, tried to determine the future of miRNAs as novel biomarkers of CVD.

Multimodality Imaging and Biomarker Approach to Characterize the Pathophysiology of Heart Failure in Left Ventricular Non-Compaction with Preserved Ejection Fraction

Left ventricular non-compaction (LVNC) with preserved ejection fraction (EF) is still a controverted entity. We aimed to characterize structural and functional changes in LVNC with heart failure with preserved EF (HFpEF).

METHODS

We enrolled 21 patients with LVNC and HFpEF and 21 HFpEF controls. For all patients, we performed CMR, speckle tracking echocardiography (STE), and biomarker assessment for HFpEF (NT-proBNP), for myocardial fibrosis (Galectin-3), and for endothelial dysfunction [ADAMTS13, von Willebrand factor, and their ratio]. By CMR, we assessed native T1 and extracellular volume (ECV) for each LV level (basal, mid, and apical). By STE, we assessed longitudinal strain (LS), globally and at each LV level, base-to-apex gradient, LS layer by layer, from epicardium to endocardium, and transmural deformation gradient.

RESULTS

In the LVNC group, mean NC/C ratio was 2.9 ± 0.4 and the percentage of NC myocardium mass was 24.4 ± 8.7%. LVNC patients, by comparison with controls, had higher apical native T1 (1061 ± 72 vs. 1008 ± 40 ms), diffusely increased ECV (27.2 ± 2.9 vs. 24.4 ± 2.5%), with higher values at the apical level (29.6 ± 3.8 vs. 25.2 ± 2.8%) (all p < 0.01); they had a lower LS only at the apical level (-21.4 ± 4.4 vs. -24.3 ± 3.2%), with decreased base-to-apex gradient (3.8 ± 4.7 vs. 6.9 ± 3.4%) and transmural deformation gradient (3.9 ± 0.8 vs. 4.8 ± 1.0%). LVNC patients had higher NT-proBNP [237 (156-489) vs. 156 (139-257) pg/mL] and Galectin-3 [7.3 (6.0-11.5) vs. 5.6 (4.8-8.3) ng/mL], and lower ADAMTS13 (767.3 ± 335.5 vs. 962.3 ± 253.7 ng/mL) and ADAMTS13/vWF ratio (all p < 0.05).

CONCLUSION

LVNC patients with HFpEF have diffuse fibrosis, which is more extensive at the apical level, explaining the decrease in apical deformation and overexpression of Galectin-3. Lower transmural and base-to-apex deformation gradients underpin the sequence of myocardial maturation failure. Endothelial dysfunction, expressed by the lower ADAMTS13 and ADAMTS13/vWF ratio, may play an important role in the mechanism of HFpEF in patients with LVNC.

Serum and synovial fluid concentrations of interleukin-18 and interleukin-20 in patients with osteoarthritis of the knee and their correlation with other markers of inflammation and turnover of joint cartilage

INTRODUCTION

Osteoarthritis (OA) is the most common degenerative joint disease, and its aetiology is not entirely known. The aim of the study was to evaluate the involvement of interleukin-18 (IL-18) and interleukin-20 (IL-20) in the pathogenesis of knee OA and their correlations with other markers of inflammation and destruction of joint cartilage, as well as clinical and radiological changes.

MATERIAL AND METHODS

The study included 25 patients with knee OA and a control group. The concentration of IL-18, IL-20, IL-6, MMP-1, MMP-3, COMP, PG-AG, and YKL-40 in serum and synovial fluid (SF) were determined. We also evaluated radiological lesions of the knee joint according to the Kellgren-Lawrence (K-L) scale, and clinical severity of the disease according to Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and Lequesne Index.

RESULTS

The concentrations of IL-18 and IL-20 were statistically significantly higher in serum of patients with OA than in the control group (106.00 ±189.76 pg/ml vs. 16.73 ±16.99 pg/ml, p < 0.001, 17.69 ±13.45 pg/ml vs. 9.76 ±9.00 pg/ml, p < 0.014). Serum concentration of IL-18 positively correlated with MMP-3 (R = 0.58; p = 0.006) and YKL-40 (R = 0.48; p = 0.002). The degree of radiological advancement of OA (K-L scale) correlated positively with clinical evaluation (WOMAC, R = 0.74, p ≤ 0.001; Lequesne Index, R = 0.57, p = 0.003).

CONCLUSIONS

The analysis of ROC curves showed that IL-20 as well as COMP, MMP-3, and YKL-40 may be diagnostic markers of knee OA. The observations indicate that IL-18 potentially mediates mainly in intra-articular processes and IL-20 could be primarily responsible for the systemic inflammatory reaction.

Role of the microRNA-29 family in myocardial fibrosis

Myocardial fibrosis (MF) is an inevitable pathological process in the terminal stage of many cardiovascular diseases, often leading to serious cardiac dysfunction and even death. Currently, microRNA-29 (miR-29) is thought to be a novel diagnostic and therapeutic target of MF. Understanding the underlying mechanisms of miR-29 that regulate MF will provide a new direction for MF therapy. In the present review, we concentrate on the underlying signaling pathway of miR-29 affecting MF and the crosstalk regulatory relationship among these pathways to illustrate the complex regulatory network of miR-29 in MF. Additionally, based on our mechanistic understanding, we summarize opportunities and challenges of miR-29-based MF diagnosis and therapy.

Circular RNA POSTN Promotes Myocardial Infarction-Induced Myocardial Injury and Cardiac Remodeling by Regulating miR-96-5p/BNIP3 Axis

Myocardial infarction (MI) is the most prevalent cardiac disease with high mortality, leading to severe heart injury. Circular RNAs (circRNAs) are a new type of regulatory RNAs and participate in multiple pathological cardiac progressions. However, the role of circRNAs Postn (circPostn) in MI modulation remains unclear. Here, we aimed to explore the effect of circPostn on MI-induced myocardial injury and cardiac remodeling. We identified that the expression of circPostn was elevated in the plasma of MI patients, MI mouse model, and hypoxia and reoxygenation (H/R)-treated human cardiomyocytes. The depletion of circPostn significantly attenuated MI-related myocardium injury and reduced the infarct size in MI mouse model. The circPostn knockdown obviously enhanced left ventricular ejection fraction (LVEF) and left ventricular fraction shortening (LVFS) and inhibited left ventricular anterior wall thickness at diastole (LVAWd) and left ventricular posterior wall thickness at diastole (LVPWd). The depletion of circPostn was able to decrease MI-induced expression of collagen 1α1 and collagen 3α1 in the ventricular tissues of mice. The protein expression of collagen and α-smooth muscle actin (SMA) was up-regulated in MI mice and was inhibited by circPostn knockdown. Meanwhile, the expression of atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) was repressed by circPostn depletion in the ventricular tissues of MI mice. Besides, the circPostn depletion attenuated cardiomyocyte apoptosis in mice. Mechanically, circPostn served as a miR-96-5p sponge and miR-96-5p-targeted BNIP3 in human cardiomyocytes, in which circPostn up-regulated BNIP3 expression by targeting miR-96-5p. circPostn promoted H/R-induced cardiomyocyte injury by modulating miR-96-5p/BNIP3 axis. Thus, we conclude that circPostn contributes to MI-induced myocardial injury and cardiac remodeling by regulating miR-96-5p/BNIP3 axis. Our finding provides new insight into the mechanism by which circPostn regulates MI-related cardiac dysfunction. circPostn, miR-96-5p, and BNIP3 are potential targets for the treatment of MI-caused heart injury.

Fibrosis in Chronic Kidney Disease: Pathogenesis and Consequences

Fibrosis is a process characterized by an excessive accumulation of the extracellular matrix as a response to different types of tissue injuries, which leads to organ dysfunction. The process can be initiated by multiple and different stimuli and pathogenic factors which trigger the cascade of reparation converging in molecular signals responsible of initiating and driving fibrosis. Though fibrosis can play a defensive role, in several circumstances at a certain stage, it can progressively become an uncontrolled irreversible and self-maintained process, named pathological fibrosis. Several systems, molecules and responses involved in the pathogenesis of the pathological fibrosis of chronic kidney disease (CKD) will be discussed in this review, putting special attention on inflammation, renin-angiotensin system (RAS), parathyroid hormone (PTH), fibroblast growth factor 23 (FGF23), Klotho, microRNAs (miRs), and the vitamin D hormonal system. All of them are key factors of the core and regulatory pathways which drive fibrosis, having a great negative kidney and cardiac impact in CKD.

Circulating miRNA-181b-5p, miRNA-223-3p, miRNA-210-3p, let 7i-5p, miRNA-21-5p and miRNA-29a-3p in patients with localized scleroderma as potential biomarkers

Localized scleroderma (LoSc) is a rare disease manifested by an inflammation and sclerosis of the skin. The latest studies focused on glycoprotein Krebs von den Lungen-6, surfactant protein-D, chemokine ligand 18 and dipeptidylpeptidase 4 as potential biomarkers of skin fibrosis in systemic scleroderma. Our study aimed to identify 6 miRNAs with elevated or decreased levels in 38 LoSc patients (31 females, 7 males) compared to healthy volunteers (HVs) and to correlate the selected miRNAs’ serum levels with the severity and the clinical symptoms of LoSc and some laboratory parameters with the selected miRNAs’ serum levels. The serum levels of miRNAs, i.e. miRNA-181b-5p, miRNA-223-3p, miRNA-21-5p, let 7i-5p, miRNA-29a-3p and miRNA-210-3p were significantly increased in the LoSc patients compared to the HVs. The level of let-7i increase in the female LoSc patients correlated negatively with BSA (r =  − 0.355, p = 0.049) and mLoSSI (r =  − 0.432, p = 0.015). Moreover, the female patients with inactive LoSc had significantly higher level of let-7i (2.68-fold on average) in comparison to those with active disease (p = 0.045). The exact role of those molecules has not been revealed in LoSc and a long-term longitudinal research is pivotal to confirm their prognostic value.

Roles of Biomarkers in Myocardial Fibrosis

Myocardial fibrosis is observed in various cardiovascular diseases and plays a key role in the impairment of cardiac function. Endomyocardial biopsy, as the gold standard for the diagnosis of myocardial fibrosis, has limitations in terms of clinical application. Therefore, biomarkers have been recommended for noninvasive assessment of myocardial fibrosis. This review discusses the role of biomarkers in myocardial fibrosis from the perspective of collagen.

Small Things Matter: Relevance of MicroRNAs in Cardiovascular Disease

MicroRNAs (miRNAs) are short sequences of non-coding RNA that play an important role in the regulation of gene expression and thereby in many physiological and pathological processes. Furthermore, miRNAs are released in the extracellular space, for example in vesicles, and are detectable in various biological fluids, such as serum, plasma, and urine. Over the last years, it has been shown that miRNAs are crucial in the development of several cardiovascular diseases (CVDs). This review discusses the (patho)physiological implications of miRNAs in CVD, ranging from cardiovascular risk factors (i.e., hypertension, diabetes, dyslipidemia), to atherosclerosis, myocardial infarction, and cardiac remodeling. Moreover, the intriguing possibility of their use as disease-specific diagnostic and prognostic biomarkers for human CVDs will be discussed in detail. Finally, as several approaches have been developed to alter miRNA expression and function (i.e., mimics, antagomirs, and target-site blockers), we will highlight the miRNAs with the most promising therapeutic potential that may represent suitable candidates for therapeutic intervention in future translational studies and ultimately in clinical trials. All in all, this review gives a comprehensive overview of the most relevant miRNAs in CVD and discusses their potential use as biomarkers and even therapeutic targets.

Potential Clinical Implications of miR-1 and miR-21 in Heart Disease and Cardioprotection

The interest in non-coding RNAs, which started more than a decade ago, has still not weakened. A wealth of experimental and clinical studies has suggested the potential of non-coding RNAs, especially the short-sized microRNAs (miRs), to be used as the new generation of therapeutic targets and biomarkers of cardiovascular disease, an ever-growing public health issue in the modern world. Among the hundreds of miRs characterized so far, microRNA-1 (miR-1) and microRNA-21 (miR-21) have received some attention and have been associated with cardiac injury and cardioprotection. In this review article, we summarize the current knowledge of the function of these two miRs in the heart, their association with cardiac injury, and their potential cardioprotective roles and biomarker value. While this field has already been extensively studied, much remains to be done before research findings can be translated into clinical application for patient’s benefit.

miR-29a activates expression of α-cardiac myosin heavy chain via β1 thyroid hormone receptor in neonatal rats

Introduction

MicroRNAs (miRs) are small noncoding RNAs which are regulators of gene expression and also regulate the genes in heart tissues. The aim of the study was to evaluate the effect of miRs on the expression level of myosin heavy chain (MHC), which is responsible for regulation of cardiac functions in neonatal rat ventricular myocytes and mice.

Material and methods

The miRs were suppressed in neonatal rat ventricular myocytes using small interfering RNAs (siRNAs) against Dicer followed by evaluation of MHC levels. For in vivo study the C57 black/6 Jacksonian mice were subjected to the transverse aortic constriction (TAC) procedure.

Results

The Dicer siRNA suppressed the endogenous miRs and the α-MHC gene but failed to down-regulate the β-MHC. Among the 17 selected miRs, miR-29a was found to up-regulate the α-MHC gene significantly but not β-MHC. The expression of α-MHC was suppressed by silencing the expression of miR-29a. Bioinformatics study done by TargetScan suggested thyroid hormone receptor-β1 (TR-β1) as a potential target of miR-29a. Additionally, miR-29a was found to regulate the expression of α-MHC via TR-β1 signaling.

Conclusions

The findings of the present study indicated that miR-29a modulates expression of α-the MHC gene by targeting TR-β1 in cardiac cells. The study may provide a new direction for treating cardiac failure and cardiac hypertrophy.

Exercise and Organ Cross Talk

Chronic heart failure, diabetes, depression, and other chronic diseases are associated with high mortality rate and low cure rate. Exercise induces muscle contraction and secretes multiple myokines, which affects the signaling pathways in skeletal muscle tissues and regulate remote organ functions. Exercise is known to be effective in treating a variety of chronic diseases. Here we summarize how exercise influences skeletal muscle, heart, brain, gut, and liver, and prevents heart failure, cognitive dysfunction, obesity, fatty liver, and other diseases. Exercise training may achieve additional benefits as compared to the present medication for these chronic diseases through cross talk among skeletal muscle and other organs.

Current understanding of fibrosis in genetic cardiomyopathies

Myocardial fibrosis is the excessive deposition of extracellular matrix proteins, including collagens, in the heart. In cardiomyopathies, the formation of interstitial fibrosis and/or replacement fibrosis is almost always part of the pathological cardiac remodeling process. Different forms of cardiomyopathies show particular patterns of myocardial fibrosis that can be considered as distinctive hallmarks. Although formation of fibrosis is initially aimed to be a reparative mechanism, in the long term, on-going and excessive myocardial fibrosis may lead to arrhythmias and stiffening of the heart wall and subsequently to diastolic dysfunction. Ultimately, adverse remodeling with progressive myocardial fibrosis can lead to heart failure. Not surprisingly, the presence of fibrosis in cardiomyopathies, even when subtle, has consistently been associated with complications and adverse outcomes. In the last decade, non-invasive in vivo techniques for visualization of myocardial fibrosis have emerged, and have been increasingly used in research and in the clinic. In this review, we will describe the epidemiology, distribution, and role of myocardial fibrosis in genetic cardiomyopathies, including hypertrophic, dilated, arrhythmogenic, and non-compaction cardiomyopathy, and a few specific forms of genetic cardiomyopathies.