MicroRNAs are aberrantly expressed in hypertrophic heart: do they play a role in cardiac hypertrophy?

MicroRNA Expression in Patients with Coronary Artery Disease and Hypertension-A Systematic Review

Coronary artery disease (CAD) and hypertension significantly contribute to cardiovascular morbidity and mortality. MicroRNAs (miRNAs) have recently emerged as promising biomarkers and therapeutic targets for these conditions. This systematic review conducts a thorough analysis of the literature, with a specific focus on investigating miRNA expression patterns in patients with CAD and hypertension. This review encompasses an unspecified number of eligible studies that employed a variety of patient demographics and research methodologies, resulting in diverse miRNA expression profiles. This review highlights the complex involvement of miRNAs in CAD and hypertension and the potential for advances in diagnostic and therapeutic strategies. Future research endeavors are imperative to validate these findings and elucidate the precise roles of miRNAs in disease progression, offering promising avenues for innovative diagnostic tools and targeted interventions.

The Role of microRNAs in Arsenic-Induced Human Diseases: A Review

MicroRNAs (miRNAs) are noncoding RNAs with 20-22 nucleotides, which are encoded by endogenous genes and are capable of targeting the majority of human mRNAs. Arsenic is regarded as a human carcinogen, which can lead to many adverse health effects including diabetes, skin lesions, kidney disease, neurological impairment, male reproductive injury, and cardiovascular disease (CVD) such as cardiac arrhythmias, ischemic heart failure, and endothelial dysfunction. miRNAs can act as tumor suppressors and oncogenes via directly targeting oncogenes or tumor suppressors. Recently, miRNA dysregulation was considered to be an important mechanism of arsenic-induced human diseases and a potential biomarker to predict the diseases caused by arsenic exposure. Endogenic miRNAs such as miR-21, the miR-200 family, miR-155, and the let-7 family are involved in arsenic-induced human disease by inducing translational repression or RNA degradation and influencing multiple pathways, including mTOR/Arg 1, HIF-1α/VEGF, AKT, c-Myc, MAPK, Wnt, and PI3K pathways. Additionally, exogenous miRNAs derived from plants, such as miR-34a, miR-159, miR-2911, miR-159a, miR-156c, miR-168, etc., among others, can be transported from blood to specific tissue/organ systems in vivo. These exogenous miRNAs might be critical players in the treatment of human diseases by regulating host gene expression. This review summarizes the regulatory mechanisms of miRNAs in arsenic-induced human diseases, including cancers, CVD, and other human diseases. These special miRNAs could serve as potential biomarkers in the management and treatment of human diseases linked to arsenic exposure. Finally, the protective action of exogenous miRNAs, including antitumor, anti-inflammatory, anti-CVD, antioxidant stress, and antivirus are described.

MicroRNA-specific therapeutic targets and biomarkers of apoptosis following myocardial ischemia-reperfusion injury

MicroRNAs are single-stranded non-coding RNAs that participate in post-transcriptional regulation of gene expression, it is involved in the regulation of apoptosis after myocardial ischemia-reperfusion injury. For example, the alteration of mitochondrial structure is facilitated by MicroRNA-1 through the regulation of apoptosis-related proteins, such as Bax and Bcl-2, thereby mitigating cardiomyocyte apoptosis. MicroRNA-21 not only modulates the expression of NF-κB to suppress inflammatory signals but also activates the PI3K/AKT pathway to mitigate ischemia-reperfusion injury. Overexpression of MicroRNA-133 attenuates reactive oxygen species (ROS) production and suppressed the oxidative stress response, thereby mitigating cellular apoptosis. MicroRNA-139 modulates the extrinsic death signal of Fas, while MicroRNA-145 regulates endoplasmic reticulum calcium overload, both of which exert regulatory effects on cardiomyocyte apoptosis. Therefore, the article categorizes the molecular mechanisms based on the three classical pathways and multiple signaling pathways of apoptosis. It summarizes the targets and pathways of MicroRNA therapy for ischemia-reperfusion injury and analyzes future research directions.

Potential roles of circulatory microRNAs in the onset and progression of renal and cardiac diseases: a focussed review for clinicians

The signalling mechanisms involving the kidney and heart are a niche of networks causing pathological conditions inducing inflammation, reactive oxidative species, cell apoptosis, and organ dysfunction during the onset of clinical complications. The clinical manifestation of the kidney and heart depends on various biochemical processes that influence organ dysfunction coexistence through circulatory networks, which hold utmost importance. The cells of both organs also influence remote communication, and evidence states that it may be explicitly by circulatory small noncoding RNAs, i.e. microRNAs (miRNAs). Recent developments target miRNAs as marker panels for disease diagnosis and prognosis. Circulatory miRNAs expressed in renal and cardiac disease can reveal relevant information about the niche of networks and gene transcription and regulated networks. In this review, we discuss the pertinent roles of identified circulatory miRNAs regulating signal transduction pathways critical in the onset of renal and cardiac disease, which can hold promising future targets for clinical diagnostic and prognostic purposes.

Stress-enhanced cardiac lncRNA Morrbid protects hearts from acute myocardial infarction

Myeloid RNA regulator of Bim-induced death (Morrbid) is a newly identified leukocyte-specific long noncoding RNA (lncRNA). However, the expression and biological functions of Morrbid in cardiomyocytes and heart disease are currently unclear. This study was meant to determine the role of cardiac Morrbid in acute myocardial infarction (AMI) and to identify the potential cellular and molecular mechanisms involved. We found that both human and mouse cardiomyocytes could express a significant amount of Morrbid and that its expression was increased in cardiomyocytes with hypoxia or oxidative stress as well as in mouse hearts with AMI. Overexpression of Morrbid reduced the myocardial infarct size and cardiac dysfunction, whereas the infarct size and cardiac dysfunction deteriorated in cardiomyocyte-specific Morrbid-KO (Morrbidfl/fl/Myh6-Cre) mice. We identified that Morrbid had a protective effect against hypoxia- or H2O2-induced apoptosis; this was also confirmed in vivo in mouse hearts after AMI. We further discovered that serpine1 was a direct target gene of Morrbid that was involved in the Morrbid-mediated protective effect on cardiomyocytes. In summary, we have found, for the first time to our knowledge, that the cardiac Morrbid is a stress-enhanced lncRNA that protects hearts from AMI via antiapoptosis through its target gene serpine1. Morrbid may be a novel promising therapeutic target for ischemic heart diseases such as AMI.

Enhancement of Bottle Gourd Oil Activity via Optimized Self-Dispersing Lipid Formulations (SDLFs) to Mitigate Isoproterenol-Evoked Cardiac Toxicity in Rats via Modulating BMP, MMP2, and miRNA-21 and miRNA-23a Genes' Expression

Bottle gourd (BG) oil (family Cucurbitaceae) has several pharmacological activities including a reduction of the hazard of cardiovascular and atherosclerosis conditions. This work aimed to develop and optimize self-dispersing lipid formulations (SDLFs) of BG oil by applying a full 32 factorial design. The formulation variables (oil concentration and surfactant mixture ratio) showed an obvious impact on the characters of the prepared BG-SDLFs including droplet size (DS), polydispersity index (PDI), emulsification time (ET), and transmission percentage (Tr%). The optimum BG-SDLF composed of 30% oil and Tween 80/Cremophor® RH40 (1:1) showed good emulsification characteristics and a better drug release profile compared with BG oil. In vivo study in isoproterenol-injected rats showed that BG oil and the optimized BG-SDLF improved cardiac function, by elevating the miRNA-23a gene expression level and decreasing miRNA-21 gene expression. They also caused the inhibition of the plasma B-type natriuretic peptide (BNP), N-terminal proatrial natriuretic peptide (NT-pro-BNP), cystatin c, galectin-3, lipoprotein-associated phospholipase A2 (Lp-PLA2), matrix metallopeptidase 2 (MMP2), cardiac troponin I (cTnI), and cardiac troponin T (cTnT). Our study demonstrated that BG oil and the optimized BG-SDLF provided a cardioprotection against isoproterenol-induced cardiac toxicity with better results in groups treated with the optimized BG-SDLF.

Mitochondrial miRNA as epigenomic signatures: Visualizing aging-associated heart diseases through a new lens

Aging bears many hard knocks, but heart disorders earn a particular allusion, being the most widespread. Cardiovascular diseases (CVDs) are becoming the biggest concern to mankind due to sundry health conditions directly or indirectly related to heart-linked abnormalities. Scientists know that mitochondria play a critical role in the pathophysiology of cardiac diseases. Both environment and genetics play an essential role in modulating and controlling mitochondrial functions. Even a minor abnormality may prove detrimental to heart function. Advanced age combined with an unhealthy lifestyle can cause most cardiomyocytes to be replaced by fibrotic tissue which upsets the conducting system and leads to arrhythmias. An aging heart encounters far more heart-associated comorbidities than a young heart. Many state-of-the-art technologies and procedures are already being used to prevent and treat heart attacks worldwide. However, it remains a mystery when this heart bomb would explode because it lacks an alarm. This calls for a novel and effective strategy for timely diagnosis and a sure-fire treatment. This review article provides a comprehensive overture of prospective potentials of mitochondrial miRNAs that predict complicated and interconnected pathways concerning heart ailments and signature compilations of relevant miRNAs as biomarkers to plot the role of miRNAs in epigenomics. This article suggests that analysis of DNA methylation patterns in age-associated heart diseases may determine age-impelled biomarkers of heart disease.

Cardiovascular Implications of microRNAs in Coronavirus Disease 2019

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic continues to be a global challenge due to resulting morbidity and mortality. Cardiovascular (CV) involvement is a crucial complication in coronavirus disease 2019 (COVID-19), and no strategies are available to prevent or specifically address CV events in COVID-19 patients. The identification of molecular partners contributing to CV manifestations in COVID-19 patients is crucial for providing early biomarkers, prognostic predictors, and new therapeutic targets. The current report will focus on the role of microRNAs (miRNAs) in CV complications associated with COVID-19. Indeed, miRNAs have been proposed as valuable biomarkers and predictors of both cardiac and vascular damage occurring in SARS-CoV-2 infection. SIGNIFICANCE STATEMENT: It is essential to identify the molecular mediators of coronavirus disease 2019 (COVID-19) cardiovascular (CV) complications. This report focused on the role of microRNAs in CV complications associated with COVID-19, discussing their potential use as biomarkers, prognostic predictors, and therapeutic targets.

Multilayer control of cardiac electrophysiology by microRNAs

The electrophysiological properties of the heart include cardiac automaticity, excitation (i.e., depolarization and repolarization of action potential) of individual cardiomyocytes, and highly coordinated electrical propagation through the whole heart. An abnormality in any of these properties can cause arrhythmias. MicroRNAs (miRs) have been recognized as essential regulators of gene expression through the conventional RNA interference (RNAi) mechanism and are involved in a variety of biological events. Recent evidence has demonstrated that miRs regulate the electrophysiology of the heart through fine regulation by the conventional RNAi mechanism of the expression of ion channels, transporters, intracellular Ca²⁺-handling proteins, and other relevant factors. Recently, a direct interaction between miRs and ion channels has also been reported in the heart, revealing a biophysical modulation by miRs of cardiac electrophysiology. These advanced discoveries suggest that miR controls cardiac electrophysiology through two distinct mechanisms: immediate action through biophysical modulation and long-term conventional RNAi regulation. Here, we review the recent research progress and summarize the current understanding of how miR manipulates the function of ion channels to maintain the homeostasis of cardiac electrophysiology.

Noncoding RNAs in Cardiac Hypertrophy and Heart Failure

Heart failure is a major global health concern. Noncoding RNAs (ncRNAs) are involved in physiological processes and in the pathogenesis of various diseases, including heart failure. ncRNAs have emerged as critical components of transcriptional regulatory pathways that govern cardiac development, stress response, signaling, and remodeling in cardiac pathology. Recently, studies of ncRNAs in cardiovascular disease have achieved significant development. Here, we discuss the roles of ncRNAs, including microRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) that modulate the cardiac hypertrophy and heart failure.

Dissecting miRNA–Gene Networks to Map Clinical Utility Roads of Pharmacogenomics-Guided Therapeutic Decisions in Cardiovascular Precision Medicine

MicroRNAs (miRNAs) create systems networks and gene-expression circuits through molecular signaling and cell interactions that contribute to health imbalance and the emergence of cardiovascular disorders (CVDs). Because the clinical phenotypes of CVD patients present a diversity in their pathophysiology and heterogeneity at the molecular level, it is essential to establish genomic signatures to delineate multifactorial correlations, and to unveil the variability seen in therapeutic intervention outcomes. The clinically validated miRNA biomarkers, along with the relevant SNPs identified, have to be suitably implemented in the clinical setting in order to enhance patient stratification capacity, to contribute to a better understanding of the underlying pathophysiological mechanisms, to guide the selection of innovative therapeutic schemes, and to identify innovative drugs and delivery systems. In this article, the miRNA–gene networks and the genomic signatures resulting from the SNPs will be analyzed as a method of highlighting specific gene-signaling circuits as sources of molecular knowledge which is relevant to CVDs. In concordance with this concept, and as a case study, the design of the clinical trial GESS (NCT03150680) is referenced. The latter is presented in a manner to provide a direction for the improvement of the implementation of pharmacogenomics and precision cardiovascular medicine trials.

Gut Microbiome-Targeted Modulations Regulate Metabolic Profiles and Alleviate Altitude-Related Cardiac Hypertrophy in Rats

It is well known that humans physiologically or pathologically respond to high altitude, with these responses accompanied by alterations in the gut microbiome. To investigate whether gut microbiota modulation can alleviate high-altitude-related diseases, we administered probiotics, prebiotics, and synbiotics in rat model with altitude-related cardiac impairment after hypobaric hypoxia challenge and observed that all three treatments alleviated cardiac hypertrophy as measured by heart weight-to-body weight ratio and gene expression levels of biomarkers in heart tissue. The disruption of gut microbiota induced by hypobaric hypoxia was also ameliorated, especially for microbes of Ruminococcaceae and Lachnospiraceae families. Metabolome revealed that hypobaric hypoxia significantly altered the plasma short-chain fatty acids (SCFAs), bile acids (BAs), amino acids, neurotransmitters, and free fatty acids, but not the overall fecal SCFAs and BAs. The treatments were able to restore homeostasis of plasma amino acids and neurotransmitters to a certain degree, but not for the other measured metabolites. This study paves the way to further investigate the underlying mechanisms of gut microbiome in high-altitude related diseases and opens opportunity to target gut microbiome for therapeutic purpose. IMPORTANCE Evidence suggests that gut microbiome changes upon hypobaric hypoxia exposure; however, it remains elusive whether this microbiome change is a merely derivational reflection of host physiological alteration, or it synergizes to exacerbate high-altitude diseases. We intervened gut microbiome in the rat model of prolonged hypobaric hypoxia challenge and found that the intervention could alleviate the symptoms of pathological cardiac hypertrophy, gut microbial dysbiosis, and metabolic disruptions of certain metabolites in gut and plasma induced by hypobaric hypoxia. Our study suggests that gut microbiome may be a causative factor for high-altitude-related pathogenesis and a target for therapeutic intervention.

Role of miRNA-1 and miRNA-21 in Acute Myocardial Ischemia-Reperfusion Injury and Their Potential as Therapeutic Strategy

Coronary artery disease remains the leading cause of death. Acute myocardial infarction (MI) is characterized by decreased blood flow to the coronary arteries, resulting in cardiomyocytes death. The most effective strategy for treating an MI is early and rapid myocardial reperfusion, but restoring blood flow to the ischemic myocardium can induce further damage, known as ischemia-reperfusion (IR) injury. Novel therapeutic strategies are critical to limit myocardial IR injury and improve patient outcomes following reperfusion intervention. miRNAs are small non-coding RNA molecules that have been implicated in attenuating IR injury pathology in pre-clinical rodent models. In this review, we discuss the role of miR-1 and miR-21 in regulating myocardial apoptosis in ischemia-reperfusion injury in the whole heart as well as in different cardiac cell types with special emphasis on cardiomyocytes, fibroblasts, and immune cells. We also examine therapeutic potential of miR-1 and miR-21 in preclinical studies. More research is necessary to understand the cell-specific molecular principles of miRNAs in cardioprotection and application to acute myocardial IR injury.

MicroRNAs Regulating Renin-Angiotensin-Aldosterone System, Sympathetic Nervous System and Left Ventricular Hypertrophy in Systemic Arterial Hypertension

MicroRNAs are small non-coding RNAs that regulate gene and protein expression. MicroRNAs also regulate several cellular processes such as proliferation, differentiation, cell cycle, apoptosis, among others. In this context, they play important roles in the human body and in the pathogenesis of diseases such as cancer, diabetes, obesity and hypertension. In hypertension, microRNAs act on the renin-angiotensin-aldosterone system, sympathetic nervous system and left ventricular hypertrophy, however the signaling pathways that interact in these processes and are regulated by microRNAs inducing hypertension and the worsening of the disease still need to be elucidated. Thus, the aim of this review is to analyze the pattern of expression of microRNAs in these processes and the possible associated signaling pathways.

MicroRNA-214 in Health and Disease

MicroRNAs (miRNAs) are endogenously expressed, non-coding RNA molecules that mediate the post-transcriptional repression and degradation of mRNAs by targeting their 3′ untranslated region (3′-UTR). Thousands of miRNAs have been identified since their first discovery in 1993, and miR-214 was first reported to promote apoptosis in HeLa cells. Presently, miR-214 is implicated in an extensive range of conditions such as cardiovascular diseases, cancers, bone formation and cell differentiation. MiR-214 has shown pleiotropic roles in contributing to the progression of diseases such as gastric and lung cancers but may also confer cardioprotection against excessive fibrosis and oxidative damage. These contrasting functions are achieved through the diverse cast of miR-214 targets. Through silencing or overexpressing miR-214, the detrimental effects can be attenuated, and the beneficial effects promoted in order to improve health outcomes. Therefore, discovering novel miR-214 targets and understanding how miR-214 is dysregulated in human diseases may eventually lead to miRNA-based therapies. MiR-214 has also shown promise as a diagnostic biomarker in identifying breast cancer and coronary artery disease. This review provides an up-to-date discussion of miR-214 literature by describing relevant roles in health and disease, areas of disagreement, and the future direction of the field.

mTOR signaling-related microRNAs as cardiac hypertrophy modulators in high-volume endurance training

Aerobic exercise training (ET) promotes cardiovascular adaptations, including physiological left ventricular hypertrophy (LVH). However, the molecular mechanisms that underlying these changes are unclear. The study aimed to elucidate specific miRNAs and target genes involved with the Akt/mTOR signaling in high-volume ET-induced LVH. Eight-week-old female Wistar rats were assigned to three groups: sedentary control (SC), trained protocol 1 (P1), and trained protocol 2 (P2). P1 consisted of 60 minutes/day of swimming, 5x/week, for 10 weeks. P2 consisted of the same protocol as P1 until the 8^th week; in the 9^th week, rats trained 2x/day, and in the 10^th week, trained 3x/day. Subsequently, structure and molecular parameters were evaluated in the heart. Trained groups demonstrate higher values to VO₂ peak, exercise tolerance, and LVH in a volume-dependent manner. The miRNA-26a-5p levels were higher in P1 and P2 compared to SC group (150±15%, d=1.8; 148±16%, d=1.7; and 100±7%, respectively, P < 0.05). In contrast, miRNA-16-5p levels were lower in P1 and P2 compared to SC group (69±5%, d=2.3, P < 0.01; 37±4%, d=5.6, P < 0.001 and 100±6%, respectively). Additionally, miRNA-16-5p knockdown and miRNA-26a-5p overexpression significantly promoted cardiomyocyte hypertrophy in neonatal rat cardiomyocytes. Both miRNAs were selected, using Diana Tolls bioinformatics website, for acting in the mTOR signaling pathway. The protein expression of Akt, mTOR, p70^S6k, and 4E-BP1 were greater in P1 and even more pronounced in P2. Nonetheless, GSK3β protein expression was lower in trained groups. Together, these molecular changes may contribute to a pronounced physiological LVH observed in high-volume aerobic training.

Identification and Characterization of Circulating MicroRNAs as Novel Biomarkers in Dogs With Heart Diseases

Background: Previous studies in humans have confirmed dysregulations of circulating microRNAs (miRNAs) in patients with various cardiovascular diseases. However, studies on circulating miRNAs in dogs with various heart diseases are limited in number. This study aimed to identify significantly dysregulated circulating miRNAs and characterize them as novel biomarkers in dogs with heart diseases. Materials and Methods: Circulating levels of 11 miRNAs were investigated in serum samples of 82 dogs (72 with heart diseases and 10 healthy dogs) using quantitative reverse transcription-polymerase chain reaction. The results were correlated to clinical data including echocardiographic results and N-terminal pro B-type natriuretic peptide (NT-proBNP) levels. Results: Upregulation of cfa-miR-130b was observed in dogs with myxomatous mitral valve degeneration (MMVD) stage B, patent ductus arteriosus, and pulmonic stenosis. In dogs with MMVD stage B, cfa-miR-130b was upregulated and correlated with clinical indices. In receiver operating characteristic (ROC) analysis, cfa-miR-130b accurately distinguished dogs with diseases from healthy dogs. We also observed that cfa-miR-375 and cfa-let-7b were upregulated in dogs with concentric cardiac hypertrophy. The cfa-miR-375 was correlated with concentric hypertrophy indices and was an accurate indicator of concentric hypertrophy in ROC analysis. Conclusions: The miRNAs identified in this study may be used as novel biomarkers and possible candidates for therapeutic targets in various canine heart diseases.

The potential use of microRNAs as a therapeutic strategy for SARS-CoV-2 infection

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, there is no effective therapeutic approach for treating SARS-CoV-2 infections. MicroRNAs (miRNAs) have been recognized to target the viral genome directly or indirectly, thereby inhibiting viral replication. Several studies have demonstrated that host miRNAs target different sites in SARS-CoV-2 RNA and constrain the production of essential viral proteins. Furthermore, miRNAs have lower toxicity, are more immunogenic, and are more diverse than protein-based and even plasmid-DNA-based therapeutic agents. In this review, we emphasize the role of miRNAs in viral infection and their potential use as therapeutic agents against COVID-19 disease. The potential of novel miRNA delivery strategies, especially EDV™ nanocells, for targeting lung tissue for treatment of SARS-CoV-2 infection is also discussed.

Non-Coding RNAs in COVID-19: Emerging Insights and Current Questions

The highly infectious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged as the causative agent of coronavirus disease 2019 (COVID-19) in late 2019, igniting an unprecedented pandemic. A mechanistic picture characterising the acute immunopathological disease in severe COVID-19 is developing. Non-coding RNAs (ncRNAs) constitute the transcribed but un-translated portion of the genome and, until recent decades, have been undiscovered or overlooked. A growing body of research continues to demonstrate their interconnected involvement in the immune response to SARS-CoV-2 and COVID-19 development by regulating several of its pathological hallmarks: cytokine storm syndrome, haemostatic alterations, immune cell recruitment, and vascular dysregulation. There is also keen interest in exploring the possibility of host-virus RNA-RNA and RNA-RBP interactions. Here, we discuss and evaluate evidence demonstrating the involvement of short and long ncRNAs in COVID-19 and use this information to propose hypotheses for future mechanistic and clinical studies.

A hybrid CNN-LSTM model for pre-miRNA classification

miRNAs (or microRNAs) are small, endogenous, and noncoding RNAs construct of about 22 nucleotides. Cumulative evidence from biological experiments shows that miRNAs play a fundamental and important role in various biological processes. Therefore, the classification of miRNA is a critical problem in computational biology. Due to the short length of mature miRNAs, many researchers are working on precursor miRNAs (pre-miRNAs) with longer sequences and more structural features. Pre-miRNAs can be divided into two groups as mirtrons and canonical miRNAs in terms of biogenesis differences. Compared to mirtrons, canonical miRNAs are more conserved and easier to be identified. Many existing pre-miRNA classification methods rely on manual feature extraction. Moreover, these methods focus on either sequential structure or spatial structure of pre-miRNAs. To overcome the limitations of previous models, we propose a nucleotide-level hybrid deep learning method based on a CNN and LSTM network together. The prediction resulted in 0.943 (%95 CI ± 0.014) accuracy, 0.935 (%95 CI ± 0.016) sensitivity, 0.948 (%95 CI ± 0.029) specificity, 0.925 (%95 CI ± 0.016) F1 Score and 0.880 (%95 CI ± 0.028) Matthews Correlation Coefficient. When compared to the closest results, our proposed method revealed the best results for Acc., F1 Score, MCC. These were 2.51%, 1.00%, and 2.43% higher than the closest ones, respectively. The mean of sensitivity ranked first like Linear Discriminant Analysis. The results indicate that the hybrid CNN and LSTM networks can be employed to achieve better performance for pre-miRNA classification. In future work, we study on investigation of new classification models that deliver better performance in terms of all the evaluation criteria.

The Psoriatic Nonlesional Skin: A Battlefield between Susceptibility and Protective Factors

In the last two decades, large-scale gene-expression studies on psoriatic skin samples revealed that even though nonlesional skin is macroscopically identical to healthy skin, it harbors several molecular differences. Originally, these molecular differences were thought to represent susceptibility factors for plaque formation. However, we review in this paper the several factors of immune regulation and structural alteration that are specific for the nonlesional skin and serve as protective factors by counteracting plaque formation and contributing to the maintenance of the nonlesional phenotype.

Identification of Nrf2-responsive microRNA networks as putative mediators of myocardial reductive stress

Although recent advances in the treatment of acute coronary heart disease have reduced mortality rates, few therapeutic strategies exist to mitigate the progressive loss of cardiac function that manifests as heart failure. Nuclear factor, erythroid 2 like 2 (Nfe2l2, Nrf2) is a transcriptional regulator that is known to confer transient myocardial cytoprotection following acute ischemic insult; however, its sustained activation paradoxically causes a reductive environment characterized by excessive antioxidant activity. We previously identified a subset of 16 microRNAs (miRNA) significantly diminished in Nrf2-ablated (Nrf2-/-) mouse hearts, leading to the hypothesis that increasing levels of Nrf2 activation augments miRNA induction and post-transcriptional dysregulation. Here, we report the identification of distinct miRNA signatures (i.e. "reductomiRs") associated with Nrf2 overexpression in a cardiac-specific and constitutively active Nrf2 transgenic (caNrf2-Tg) mice expressing low (TgL) and high (TgH) levels. We also found several Nrf2 dose-responsive miRNAs harboring proximal antioxidant response elements (AREs), implicating these "reductomiRs" as putative meditators of Nrf2-dependent post-transcriptional regulation. Analysis of mRNA-sequencing identified a complex network of miRNAs and effector mRNAs encoding known pathological hallmarks of cardiac stress-response. Altogether, these data support Nrf2 as a putative regulator of cardiac miRNA expression and provide novel candidates for future mechanistic investigation to understand the relationship between myocardial reductive stress and cardiac pathophysiology.

microRNAs involved in psoriasis and cardiovascular diseases

Psoriasis is a chronic inflammatory disease involving the skin. Both genetic and environmental factors play a pathogenic role in psoriasis and contribute to the severity of the disease. Psoriasis, in fact, has been associated with different comorbidities such as diabetes, metabolic syndrome, gastrointestinal or kidney diseases, cardiovascular disease (CVD), and cerebrovascular diseases (CeVD). Indeed, life expectancy in severe psoriasis is reduced by up to 5 years due to CVD and CeVD. Moreover, patients with severe psoriasis have a higher prevalence of traditional cardiovascular (CV) risk factors, including dyslipidemia, diabetes, smoking, and hypertension. Further, systemic inflammation is associated with oxidative stress increase and induces endothelial damage and atherosclerosis progression. Different miRNA have been already described in psoriasis, both in the skin tissues and in the blood flow, to play a role in the progression of disease. In this review, we will summarize and discuss the most important miRNAs that play a role in psoriasis and are also linked to CVD.

The Impact of microRNAs in Renin-Angiotensin-System-Induced Cardiac Remodelling

Current knowledge on the renin-angiotensin system (RAS) indicates its central role in the pathogenesis of cardiovascular remodelling via both hemodynamic alterations and direct growth and the proliferation effects of angiotensin II or aldosterone resulting in the hypertrophy of cardiomyocytes, the proliferation of fibroblasts, and inflammatory immune cell activation. The noncoding regulatory microRNAs has recently emerged as a completely novel approach to the study of the RAS. A growing number of microRNAs serve as mediators and/or regulators of RAS-induced cardiac remodelling by directly targeting RAS enzymes, receptors, signalling molecules, or inhibitors of signalling pathways. Specifically, microRNAs that directly modulate pro-hypertrophic, pro-fibrotic and pro-inflammatory signalling initiated by angiotensin II receptor type 1 (AT1R) stimulation are of particular relevance in mediating the cardiovascular effects of the RAS. The aim of this review is to summarize the current knowledge in the field that is still in the early stage of preclinical investigation with occasionally conflicting reports. Understanding the big picture of microRNAs not only aids in the improved understanding of cardiac response to injury but also leads to better therapeutic strategies utilizing microRNAs as biomarkers, therapeutic agents and pharmacological targets.

Periodontal Pathogens and Neuropsychiatric Health

Increasing evidence incriminates low-grade inflammation in cardiovascular, metabolic diseases, and neuropsychiatric clinical conditions, all important causes of morbidity and mortality. One of the upstream and modifiable precipitants and perpetrators of inflammation is chronic periodontitis, a polymicrobial infection with Porphyromonas gingivalis (P. gingivalis) playing a central role in the disease pathogenesis. We review the association between P. gingivalis and cardiovascular, metabolic, and neuropsychiatric illness, and the molecular mechanisms potentially implicated in immune upregulation as well as downregulation induced by the pathogen. In addition to inflammation, translocation of the pathogens to the coronary and peripheral arteries, including brain vasculature, and gut and liver vasculature has important pathophysiological consequences. Distant effects via translocation rely on virulence factors of P. gingivalis such as gingipains, on its synergistic interactions with other pathogens, and on its capability to manipulate the immune system via several mechanisms, including its capacity to induce production of immune-downregulating micro-RNAs. Possible targets for intervention and drug development to manage distal consequences of infection with P. gingivalis are also reviewed.

miR-22 Host Gene Enhances Nuclear Factor-kappa B Activation to Aggravate Hypoxia-induced Injury in AC16 Cardiomyocytes

Myocardial infarction (MI) is a severe life-threatening disease caused by acute and persistent ischemia and hypoxia and eventually leads to heart failure and sudden death. Long noncoding RNAs (lncRNAs) play significant roles in the pathology, diagnosis, and development of various cardiovascular diseases, including MI. This study aimed to explore the effect and molecular mechanism of lncRNA miR-22 host gene (MIR22HG) on hypoxia-induced injury in AC16 cardiomyocytes. The expression of MIR22HG and miR-24 in hypoxia-treated AC16 cardiomyocytes was detected by quantitative real-time polymerase chain reaction. Cell viability, lactate dehydrogenase release, levels of aspartate aminotransferase (AST) and creatine kinase-MB (CK-MB), and apoptosis were detected by Cell Counting Kit-8, lactate dehydrogenase (LDH) release assay, commercial enzyme-linked immune sorbent assay kits, and flow cytometry analysis, respectively. The protein levels of nuclear factor-kappa B (NF-κB) p65 and cytoplasmic inhibitor of kappa B alpha (IκBα) and phosphorylated IκBα were detected by western blot. Results showed that hypoxia treatment decreased viability and increased MIR22HG expression in AC16 cardiomyocytes. MIR22HG overexpression aggravated hypoxia-induced viability reduction, leakage of myocardial injury markers LDH, AST, and CK-MB, and apoptosis in AC16 cardiomyocytes, while MIR22HG knockdown elicited the reverse effects. MIR22HG overexpression enhanced NF-κB activation in hypoxia-treated AC16 cardiomyocytes. Inhibition of NF-κB pathway impaired the effects of MIR22HG overexpression on hypoxia-induced injury in AC16 cardiomyocytes. Moreover, MIR22HG knockdown inhibited the NF-κB pathway by upregulating miR-24 in AC16 cardiomyocytes. Inhibition of miR-24 resisted the effects of MIR22HG silencing on hypoxia-induced injury in AC16 cardiomyocytes. In conclusion, MIR22HG overexpression aggravated hypoxia-induced injury in AC16 cardiomyocytes via enhancing NF-κB activation by targeting miR-24.

The role of miR-29 family in disease

MicroRNAs are small noncoding RNAs that can bind to the target sites in the 3’‐untranslated region of messenger RNA to regulate posttranscriptional gene expression. Increasing evidence has identified the miR‐29 family, consisting of miR‐29a, miR‐29b‐1, miR‐29b‐2, and miR‐29c, as key regulators of a number of biological processes. Moreover, their abnormal expression contributes to the etiology of numerous diseases. In the current review, we aimed to summarize the differential expression patterns and functional roles of the miR‐29 family in the etiology of diseases including osteoarthritis, osteoporosis, cardiorenal, and immune disease. Furthermore, we highlight the therapeutic potential of targeting members of miR‐29 family in these diseases. We present miR‐29s as promoters of osteoblast differentiation and apoptosis but suppressors of chondrogenic and osteoclast differentiation, fibrosis, and T cell differentiation, with clear avenues for therapeutic manipulation. Further research will be crucial to identify the precise mechanism of miR‐29 family in these diseases and their full potential in therapeutics.

A meta-analysis of microRNA expression profiling studies in heart failure

Heart failure (HF) is a major consequence of many cardiovascular diseases with high rate of morbidity and mortality. Early diagnosis and prevention are hampered by the lack of informative biomarkers. The aim of this study was to perform a meta-analysis of the miRNA expression profiling studies in HF to identify novel candidate biomarkers or/and therapeutic targets. A comprehensive literature search of the PubMed for miRNA expression studies related to HF was carried out. The vote counting and robust rank aggregation meta-analysis methods were used to identify significant meta-signatures of HF-miRs. The targets of HF-miRs were identified, and network construction and gene set enrichment analysis (GSEA) were performed to identify the genes and cognitive pathways most affected by the dysregulation of the miRNAs. The literature search identified forty-five miRNA expression studies related to CHF. Shared meta-signature was identified for 3 up-regulated (miR-21, miR-214, and miR-27b) and 13 down-regulated (miR-133a, miR-29a, miR-29b, miR-451, miR-185, miR-133b, miR-30e, miR-30b, miR-1, miR-150, miR-486, miR-149, and miR-16-5p) miRNAs. Network properties showed miR-29a, miR-21, miR-29b, miR-1, miR-16, miR-133a, and miR-133b have the most degree centrality. GESA identified functionally related sets of genes in signaling and community pathways in HF that are the targets of HF-miRs. The miRNA expression meta-analysis identified sixteen highly significant HF-miRs that are differentially expressed in HF. Further validation in large patient cohorts is required to confirm the significance of these miRs as HF biomarkers and therapeutic targets.

A narrative review of the roles of the miR-15/107 family in heart disease: lessons and prospects for heart disease

Heart disease is one of the leading causes of morbidity and mortality globally. To reduce morbidity and mortality among patients with heart disease, it is important to identify drug targets and biomarkers for more effective diagnosis, prognosis, and treatment. MicroRNAs (miRNAs) are characterized as a group of endogenous, small non-coding RNAs, which function by directly inhibiting target genes. The miR-15/107 family is a group of evolutionarily conserved miRNAs comprising 10 members that share an identical motif of AGCAGC, which determines overlapping target genes and cooperation in the biological process. Accumulating evidence has demonstrated the predominant dysregulation of the miR-15/107 family in cardiovascular disease, neurodegenerative disease, and cancer. In this review, we summarize the current understanding of the miR-15/107 family, focusing on its role in the regulation in the development of the heart and the progression of heart disease. We also discuss the potential of different members of the miR-15/107 family as biomarkers for diverse heart disease, as well as the current applications and challenges in the use of the miR-15/107 family in clinical trials for various disease. This paper hopes to explore the potential of the miR-15/107 family as therapeutic targets or biomarkers and to provide directions for future research.

Application of microRNA Database Mining in Biomarker Discovery and Identification of Therapeutic Targets for Complex Disease

Over the past two decades, it has become increasingly evident that microRNAs (miRNA) play a major role in human diseases such as cancer and cardiovascular diseases. Moreover, their easy detection in circulation has made them a tantalizing target for biomarkers of disease. This surge in interest has led to the accumulation of a vast amount of miRNA expression data, prediction tools, and repositories. We used the Human microRNA Disease Database (HMDD) to discover miRNAs which shared expression patterns in the related diseases of ischemia/reperfusion injury, coronary artery disease, stroke, and obesity as a model to identify miRNA candidates for biomarker and/or therapeutic intervention in complex human diseases. Our analysis identified a single miRNA, hsa-miR-21, which was casually linked to all four pathologies, and numerous others which have been detected in the circulation in more than one of the diseases. Target analysis revealed that hsa-miR-21 can regulate a number of genes related to inflammation and cell growth/death which are major underlying mechanisms of these related diseases. Our study demonstrates a model for researchers to use HMDD in combination with gene analysis tools to identify miRNAs which could serve as biomarkers and/or therapeutic targets of complex human diseases.

The Cell Type-Specific Functions of miR-21 in Cardiovascular Diseases

Cardiovascular diseases are one of the prime reasons for disability and death worldwide. Diseases and conditions, such as hypoxia, pressure overload, infection, and hyperglycemia, might initiate cardiac remodeling and dysfunction by inducing hypertrophy or apoptosis in cardiomyocytes and by promoting proliferation in cardiac fibroblasts. In the vascular system, injuries decrease the endothelial nitric oxide levels and affect the phenotype of vascular smooth muscle cells. Understanding the underlying mechanisms will be helpful for the development of a precise therapeutic approach. Various microRNAs are involved in mediating multiple pathological and physiological processes in the heart. A cardiac enriched microRNA, miR-21, which is essential for cardiac homeostasis, has been demonstrated to act as a cell–cell messenger with diverse functions. This review describes the cell type–specific functions of miR-21 in different cardiovascular diseases and its prospects in clinical therapy.

G6PD, bond by miR-24, regulates mitochondrial dysfunction and oxidative stress in phenylephrine-induced hypertrophic cardiomyocytes

AIMS

Pathological cardiac hypertrophy (CH) is one of the main risk factors for heart failure and cardiac death. Mitochondrial dysfunction and oxidative stress often occur in hypertrophic cardiomyocytes. It was recently proposed that deficiency or decreased activity of glucose-6-phosphate dehydrogenase (G6PD) may be related to the development of CH. This study aimed to investigate the expression of G6PD in CH and its regulatory role in mitochondrial dysfunction and oxidative stress of CH cells.

MAIN METHODS

Phenylephrine (PE) was used to create an in vitro model of CH. Using RT-qPCR and western blotting, the expression levels of target mRNAs and proteins were measured. ELISA assays and commercial kits based on spectrophotometry or colorimetry were used to measure mitochondrial function and oxidative stress. TargetScan and luciferase reporter gene assays were utilized for combination prediction and validation. CCK-8 and TUNEL kit were used to determine cell viability and apoptosis.

KEY FINDINGS

The results showed that G6PD overexpression attenuated the decreases of mitochondrial respiration, ATP, ATP synthetase and mitochondrial membrane potential induced by PE, as well as the increases of LDH release and apoptosis. Besides, PE elevated ROS activity, NO and MDA contents, and reduced SOD, CAT levels and cell viability. These effects were hindered by G6PD overexpression. MiR-24 was found to directly bind to G6PD at the motif of CUGAGCC and regulated its expression, furtherly, influenced the G6PD-mediated mitochondrial dysfunction and oxidative stress of CH cells.

SIGNIFICANCE

Generally, our study demonstrated that miR-24/G6PD regulates mitochondrial dysfunction and oxidative stress in CH cells, representing a new sight for CH therapy.

LINC02418 promotes malignant behaviors in lung adenocarcinoma cells by sponging miR-4677-3p to upregulate KNL1 expression

Background

Lung adenocarcinoma (LAD) is a prevalent type of bronchogenic malignant tumor and one of the most critical factors related to human death. Long noncoding RNAs (lncRNAs) are involved in many complex biological processes and have been emerged as extremely important regulators of various cancers. LINC02418, a novel lncRNA, hasn’t been mentioned in previous studies on cancer development. Therefore, it’s important to define the potential function of LINC02418 in LAD.

Methods

Gene expression was examined by RT-qPCR or western blot. CCK-8, colony formation, TUNEL, and transwell assays were utilized to study the role of LINC02418 in LAD. The interaction of miR-4677-3p with LINC02418 (or KNL1) was verified through luciferase reporter, RIP and RNA pull-down assays.

Results

High expression of LINC02418 was observed in LAD specimens and cells. Downregulation of LINC02418 obstructed the proliferation and motility of LAD cells. Moreover, LINC02418 negatively modulated miR-4677-3p expression and miR-4677-3p overexpression could repress cell proliferation and migration. Moreover, kinetochore scaffold 1 (KNL1) expression was negatively modulated by miR-4677-3p but positively regulated by LINC02418. Furthermore, miR-4677-3p could bind with LINC02418 (or KNL1). Finally, KNL1 overexpression reversed the inhibitory function of LINC02418 deficiency in the malignant behaviors of LAD cells.

Conclusions

LINC02418 contributes to the malignancy in LAD via miR-4677-3p/KNL1 signaling, providing a probable therapeutic direction for LAD.

Silencing miR-370-3p rescues funny current and sinus node function in heart failure

Bradyarrhythmias are an important cause of mortality in heart failure and previous studies indicate a mechanistic role for electrical remodelling of the key pacemaking ion channel HCN4 in this process. Here we show that, in a mouse model of heart failure in which there is sinus bradycardia, there is upregulation of a microRNA (miR-370-3p), downregulation of the pacemaker ion channel, HCN4, and downregulation of the corresponding ionic current, If, in the sinus node. In vitro, exogenous miR-370-3p inhibits HCN4 mRNA and causes downregulation of HCN4 protein, downregulation of If, and bradycardia in the isolated sinus node. In vivo, intraperitoneal injection of an antimiR to miR-370-3p into heart failure mice silences miR-370-3p and restores HCN4 mRNA and protein and If in the sinus node and blunts the sinus bradycardia. In addition, it partially restores ventricular function and reduces mortality. This represents a novel approach to heart failure treatment.

Ultrasonic cardiogram and MiRNA-21 analysis of cardiac dysfunction in patients with cardiac arrest following cardiopulmonary resuscitation

PURPOSE

To explore correlations between the serum level of miRNA-21 expression and cardiac dysfunction severity after cardiopulmonary resuscitation (CPR) using ultrasonic cardiogram.

METHODS

Thirty-nine patients with cardiopulmonary arrest receiving successful CPR and forty-one healthy participants were recruited in the study. Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and immunochemiluminometric assays was used to examine the serum miRNA-21 level and the concentration of cardiac troponins T and I, respectively. Indices of Electrocardiogram (ECG) and cardiac dysfunction measured by ultrasound of patients in the case group were used to assess cardiac function after CPR. Furthermore, the correlation between the serum level of miRNA-21 expression and severity of cardiac dysfunction was analyzed by Spearman correlation analysis.

RESULTS

As compared to the control group, the serum level of miRNA-21 expression, as well as cardiac troponin T and I levels in the case group were significantly higher (p = 0.000). The miRNA-21 expression level in the patients at IV grade of cardiac function were substantially higher than patients at III grade (p = 0.015). There was no significant difference in level of cardiac troponins T and I between patients at III grade and patients at IV grade (p > 0.05). Further, Spearman correlation analysis revealed that the level of miRNA-21 expression was negatively correlated with cardiac function index in the ultrasound imaging: E peak, E/A value, LVEF and LVEDD (r = 0.617, 0.535, 0.612, 0.573, P = 0.012, 0.009, 0.008, 0.011), but was positively correlated with the level of cardiac troponins T and I (r = 0.546,0.582, P = 0.006,0.007) and the severity of cardiac dysfunction (r = 0.859, p < 0.05).

CONCLUSION

The level of miRNA-21 is higher after CPR is closely related to the severity of cardiac dysfunction that is measured by ultrasound, suggesting that it may serve as a potential biomarker.

Prevention of heart failure with preserved ejection fraction (HFpEF): reexamining microRNA-21 inhibition in the era of oligonucleotide-based therapeutics

Heart failure with preserved ejection fraction (HFpEF) accounts for 50% of cases of heart failure, which is the most common cause of hospitalization in US patients over the age of 65. HFpEF pathogenesis is increasingly believed to be due to pathological hypertrophy and fibrosis of the myocardium that may be a result of systemic inflammation from comorbid conditions such as hypertension, diabetes mellitus, chronic obstructive pulmonary disease, anemia, chronic kidney disease and others. It is believed that oxidative stress triggers a process of pathological hypertrophy and fibrosis in cardiac endothelial cells, which leads to increased left ventricle filling pressures and, eventually, symptoms of heart failure. Numerous recent major clinical trials that have examined various therapies aimed at improving mortality in HFpEF have emerged empty-handed and thus the search for effective management strategies continues. Over the last several years, there have been many new developments in the field of antisense oligonucleotide-based therapeutics, which involves using noncoding nucleic acid particles such as microRNA and small interfering RNA to repress the expression of specific messenger RNA. In this article, we review the concept of using oligonucleotide-based therapeutics to prevent or treat HFpEF by targeting a specific microRNA that has been implicated in the pathogenesis of myocardial fibrosis and hypertrophy, microRNA-21 (miR-21). We review the various evidence that implicates miR-21 in the process of myocardial fibrosis and discuss recent attempts to use antimiR-21 compounds to prevent fibrosis. We also discuss proposed methods for screening patients at high risk for HFpEF for diastolic dysfunction in order to determine which patients.

LncRNA-GAS5 regulates PDCD4 expression and mediates myocardial infarction-induced cardiomyocytes apoptosis via targeting MiR-21

The present study was designed to investigate whether and how lncRNA-GAS5 regulates cardiomyocyte apoptosis in MI. MI rat model was established by the left anterior descending (LAD) coronary artery ligation. MI model was further evaluated by biomarkers detection and TUNEL, HE and Masson staining. The roles of lncRNA-GAS5 on hypoxia/reoxygenation (H/R)-induced cardiomyocytes survival, cell cycle arrest, and apoptosis were examined by MTT and flow cytometry in rat heart-derived H9c2 cells. Western blot was used to determine the effect of GAS5 on the expression of apoptosis-associated proteins and PI3 K/AKT signaling pathway. The direct bindings of GAS5 to miR-21 and miR-21 to PDCD4 were measured by dual-luciferase reporter assay or RNA immunoprecipitation. Decreased expressions of GAS5 and PDCD4 as well as increased miR-21 level were observed in the hearts of MI-modeled rat, accompanying with morphologically myocardial cell injury, as well as collagen deposition and fibrosis, and elevated levels of cTnl, CK, CK-MB and LDH. In the cell model, the knockdown of GAS5 promoted cell survival, prevented cell cycle arrest and inhibited cell apoptosis while the overexpression of GAS5 showed the opposite effects. GAS5 was found to downregulate miR-21 and the effects of GAS5 were attenuated by miR-21 mimics. GAS5 positively regulated PDCD4 expression by functioning as a sponge of miR-21 in H/R model. Moreover, GAS5 stimulated PDCD4 and suppressed PI3 K/AKT signal pathway. LncRNA-GAS5 regulates PDCD4 expression to mediate MI-induced cardiomyocyte apoptosis via targeting miR-21, suggesting that GAS5 could be a therapeutic target for MI.

Prospective Advances in Non-coding RNAs Investigation

Non-coding RNAs (ncRNAs) play significant roles in numerous physiological cellular processes and molecular alterations during pathological conditions including heart diseases, cancer, immunological disorders and neurological diseases. This chapter is focusing on the basis of ncRNA relation with their functions and prospective advances in non-coding RNAs particularly miRNAs investigation in the cardiovascular disease management.The field of ncRNAs therapeutics is a very fascinating and challenging too. Scientists have opportunity to develop more advanced therapeutics as well as diagnostic approaches for cardiovascular conditions. Advanced studies are critically needed to deepen the understanding of the molecular biology, mechanism and modulation of ncRNAs and chemical formulations for managing CVDs.

MicroRNA-29a attenuates angiotensin-II induced-left ventricular remodeling by inhibiting collagen, TGF-β and SMAD2/3 expression

Background

Left ventricular (LV) remodeling is the most common target organ damage in hypertension. Previously, our study found that plasma microRNA-29a (miR-29a) level was associated with the LV remodeling in hypertensive patients. However, the causal relationship between miR-29a and LV remodeling remains unknown. Thus, the aim of this study was to investigate the regulation mechanism of miR-29a in LV remodeling.

Methods & Results

Overexpression and knockdown miR-29a mice were generated by tail-intravenous injection of miR-29a-mimic and inhibitor lentivirus for one week respectively. Then the mice were subjected to angiotensin-II (AngII) induced LV remodeling by subcutaneous AngII capsule osmotic pumping into AngII for four weeks. AngII-induced LV remodeling mice as the model group (n = 9). Age-matched male SPF C57/BL6J mice (6-8 weeks old) were treated with the pumping of saline as a vehicle (n = 6). In vivo, overexpression miR-29a ameliorated AngII-induced LV remodeling, while knockdown miR-29a deteriorated LV remodeling. Simultaneously, we observed that overexpression miR-29a mice inhibited but knockdown miR-29a mice increased cardiac cross-sectional area, indicating that miR-29a has an antagonistic effect on cardiac hypertrophy. Further studies found that overexpression miR-29a inhibited the content of the LV collagen including collagen I and III. Moreover, the expression of transforming growth factor-β (TGF-β) and phosphorylated SMAD2/3 decreased with the down-regulation of collagen I and III in overexpression miR-29a mice.

Conclusions

Our finding indicates that overexpression miR-29a attenuates LV remodeling by inhibiting collagen deposition, TGF-β, and phosphorylated SMAD2/3 expression. Thus, intervention miR-29a may be a therapeutic target for attenuating LV remodeling.

Pharmacological Silencing of MicroRNA-152 Prevents Pressure Overload-Induced Heart Failure

BACKGROUND

MicroRNAs are small, noncoding RNAs that play a key role in gene expression. Accumulating evidence suggests that aberrant microRNA expression contributes to the heart failure (HF) phenotype; however, the underlying molecular mechanisms are not well understood. A better understanding of the mechanisms of action of microRNAs could potentially lead to targeted therapies that could halt the progression or even reverse HF.

METHODS AND RESULTS

We found that microRNA-152 (miR-152) expression was upregulated in the failing human heart and experimental animal models of HF. Transgenic mice with cardiomyocyte-specific miR-152 overexpression developed systolic dysfunction (mean difference, -38.74% [95% CI, -45.73% to -31.74%]; P<0.001) and dilated cardiomyopathy. At the cellular level, miR-152 overexpression perturbed mitochondrial ultrastructure and dysregulated key genes involved in cardiomyocyte metabolism and inflammation. Mechanistically, we identified Glrx5 (glutaredoxin 5), a critical regulator of mitochondrial iron homeostasis and iron-sulfur cluster synthesis, as a direct miR-152 target. Finally, a proof-of-concept of the therapeutic efficacy of targeting miR-152 in vivo was obtained by utilizing a locked nucleic acid-based inhibitor of miR-152 (LNA 152) in a murine model of HF subjected to transverse aortic constriction. We demonstrated that animals treated with LNA-152 (n=10) showed preservation of systolic function when compared with locked nucleic acid-control treated animals (n=9; mean difference, 18.25% [95% CI, 25.10% to 11.39%]; P<0.001).

CONCLUSIONS

The upregulation of miR-152 expression in the failing myocardium contributes to HF pathophysiology. Preclinical evidence suggests that miR-152 inhibition preserves cardiac function in a model of pressure overload-induced HF. These findings offer new insights into the pathophysiology of HF and point to miR-152-Glrx5 axis as a potential novel therapeutic target.

MiR-142-5p Protects Against 6-OHDA-Induced SH-SY5Y Cell Injury by Downregulating BECN1 and Autophagy

Background

MiR-142-5p has been demonstrated to hold significant implications in neurological diseases. However, the impact and underlying regulatory mechanism of miR-142-5p in Parkinson's disease (PD) are still ominous.

Methods

To simulate the PD, 6-hydroxydopamine (6-OHDA)-treated SH-SY5Y cell model was used in this study. Levels of messenger RNA and protein were tested by quantitative real-time polymerase chain reaction and Western blot analyses, respectively. The direct interaction between miR-142-5p and Beclin 1 (BECN1) was assessed by luciferase reporter assay. Furthermore, Cell Counting Kit-8 assay was performed to assess cytotoxicity of SH-SY5Y cell.

Results

In consequence, a significant decrease of miR-142-5p was observed in 6-OHDA-induced SH-SY5Y cells. Over-/Low-expressed miR-142-5p resulted in a significant enhancement/inhibition on cell vitalities of 6-OHDA-treated SH-SY5Y cells, which might be modulated by repressing cellular autophagy through inhibiting level of BECN1 and LC3 II/LC3 I and elevating P62 level. Luciferase reporter assay showed that the BECN1 was the target gene of miR-142-5p. Additionally, the loss/gain of BECN1 rescued/blocked the effects of miR-142-5p on the viability of 6-OHDA-induced SH-SY5Y cells.

Conclusions

These results highlight that miR-142-5p functions as a neuroprotective regulator in 6-OHDA-induced neuronal SH-SY5Y cells simulating PD model in vitro via regulating autophagy-related protein BECN1 and autophagy to influence cell viability.

Small Molecules with Big Impacts on Cardiovascular Diseases

Cardiovascular diseases (CVDs) are the leading cause of morbidity and mortality worldwide. Although in recent years there has been a significant progress in the diagnosis, treatment, and prognosis of CVD, but due to their complex pathobiology, developing novel biomarkers and therapeutic interventions are still in need. MicroRNAs (miRNAs) are a fraction of non-coding RNAs that act as micro-regulators of gene expression. Mounting evidences over the last decade confirmed that microRNAs were deregulated in several CVDs and manipulating their expression could affect homeostasis, differentiation, and function of cardiovascular system. Here, we review the current knowledge concerning the roles of miRNAs in cardiovascular diseases with more details on cardiac remodeling, arrhythmias, and atherosclerosis. In addition, we discuss the latest findings on the potential therapeutic applications of miRNAs in cardiovascular diseases.

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.

Non-coding RNAs and Pathological Cardiac Hypertrophy

Cardiovascular disease (CVD) is a common disease which poses a serious threat to human health and it is characterized by high prevalence, high disability and high mortality. Myocardial hypertrophy (MH) is a common pathological process of various cardiovascular diseases and is considered as an independent risk factor for increased cardiovascular morbidity and mortality. Therefore, it is particularly important to understand its pathological mechanism and treatment. In recent years, it has been found that many non-coding RNAs (ncRNAs) play key regulatory roles in humans' various pathophysiological processes. Abnormal expression of ncRNAs in different types of cardiac cells is associated with pathological cardiac hypertrophy. Understanding the relationship between various ncRNAs and intercellular communication through extracellular vesicles (EV) can identify the key ncRNAs which are the accurate targets of precise therapy in this network of action, it also can potentially be a marker for clinical disease diagnosis, which will reflect the progress of the disease earlier and more accurately. There are many factors that regulate the occurrence and development of cardiac hypertrophy, ncRNAs are only a part of them. There are also mutual promotion or inhibition between ncRNAs and other molecules. It will be helpful for us to comprehend the mechanism of cardiac hypertrophy better and provide a sufficient theoretical basis for clinical diagnosis and treatment by defining these relationships.

Dynamics of Soluble Thrombomodulin and Circulating miRNAs in Patients with Atrial Fibrillation Undergoing Radiofrequency Catheter Ablation

Atrial fibrillation (AF) is the most common cardiac arrhythmia in the world and has a high risk of thromboembolism. The most effective approach, catheter ablation, requires evaluation by electrocardiography. The aim of our study was to investigate novel clinical markers that predict restoration of sinus rhythm (SR) after catheter ablation. Seventy-eight consecutive patients with AF underwent catheter ablation and were separated into 2 groups: restored SR and recurrent AF. The levels of 4 blood proteins (serum or plasma) and 3 mature microRNAs (miRNAs) and their primary miRNAs (pri-miRNAs) in serum were measured before and after ablation, and the associations between each parameter were analyzed statistically. Soluble thrombomodulin (s-TM) and plasminogen activator inhibitor-1 (PAI-1) levels increased above baseline after ablation in both the restored SR (s-TM 11.55 [2.92] vs 13.75 [3.38], P < .001; PAI-1 25.74 [15.25] vs 37.79 [19.56], P < .001) and recurrent AF (s-TM 10.28 [2.78] vs 11.67 [3.37], P < .001; PAI-1 26.16 [15.70] vs 40.74 [22.55], P < .001) groups. Levels of C-reactive protein and asymmetric dimethylarginine were not significantly changed. Pri-miR-126 levels significantly decreased after ablation in the recurrent AF group, but the other miRNAs and pri-miRNAs did not. The measurement of s-TM and pri-miR-126 in blood was a useful tool to reflect the condition of AF patients with catheter ablation.

microRNA-1 inhibits cardiomyocyte proliferation in mouse neonatal hearts by repressing CCND1 expression

Background

The functions of microRNA-1 (miR-1) in cardiac hypertrophy, and cardiomyocyte differentiation have been investigated. However, the mechanism on how miR-1 could repress cardiomyocyte proliferation has not been fully elucidated.

Methods

We address this issue by investigating whether miR-1 affected the proliferation of neonatal cardiomyocyte and identify some of the genes targeted by miR-1. miR-1 was over-expressed in neonatal cardiomyocytes and the effect on cell cycle and growth were analyzed by flow cytometry and Brdu-incorporation assay. Relevant vectors carrying the luciferase reporter were constructed for validation of miR-1 binding to its matching sites on the 3'-untranslated region of the predicated target mRNAs. Cardiomyocytes were co-transfected with the vectors and miR-1 mimics, then luciferase reporter assay was performed. Lastly, we examined the expression of target genes in cardiomyocytes after transfection with miR-1 mimics, as well as their normal expression pattern in 2- and 13-day-old mice hearts.

Results

We have demonstrated that miR-1 was the most significantly upregulated miRNA in 13-day-old mouse hearts compared with 2-day-old hearts. We also showed that miR-1 could repress cardiomyocyte G1/S phase transition, proliferation and viability. IGF1 and CCND1 were identified as candidate target genes regulated by miR-1. In addition, overexpression of miR-1 could suppress the expression of these two genes at the mRNA level. It could also correspondingly inhibit CCND1 expression at the protein level but not for IGF1.

Conclusions

Our results suggest that miR-1 plays an important role in inhibiting cardiomyocyte proliferation in the developing neonatal mouse heart by directly suppressing the cell-cycle regulator, CCND1.

Electrochemical-based biosensors for microRNA detection: Nanotechnology comes into view

Nanotechnology plays an undeniable significant role in medical sciences, particularly in the field of biomedicine. Development of several diagnostic procedures in medicine has been possible through the beneficial application of nano-materials, among which electrochemical nano-biosensors can be mentioned. They can be employed to quantify various clinical biomarkers in detection, evaluation, and follow up stages of the illnesses. MicroRNAs, a group of regulatory short RNA fragments, added a new dimension to the management and diagnosis of several diseases. Mature miRNAs are single-stranded RNA molecules approximately 22 nucleotides in length, which regulate a vast range of biological functions from cellular proliferation and death to cancer development and progression. Recently, diagnostic value of miRNAs in various diseases has been demonstrated. There are many traditional methods for detection of miRNAs including northern blotting, quantitative real time PCR (qRT-PCR), microarray technology, nanotechnology-based approaches, and molecular biology tools including miRNA biosensors. In comparison with other techniques, electrochemical nucleic acid biosensor methods exhibit many interesting features, and could play an important role in the future nucleic acid analysis. This review paper provides an overview of some different types of nanotechnology-based biosensors for detection of miRNAs.