MicroRNA-203 enhances coxsackievirus B3 replication through targeting zinc finger protein-148

Infectious factors in myocarditis: a comprehensive review of common and rare pathogens

BACKGROUND

Myocarditis is a significant health threat today, with infectious agents being the most common cause. Accurate diagnosis of the etiology of infectious myocarditis is crucial for effective treatment.

MAIN BODY

Infectious myocarditis can be caused by viruses, prokaryotes, parasites, and fungi. Viral infections are typically the primary cause. However, some rare opportunistic pathogens can also damage heart muscle cells in patients with immunodeficiencies, neoplasms and those who have undergone heart surgery.

CONCLUSIONS

This article reviews research on common and rare pathogens of infectious myocarditis, emphasizing the complexity of its etiology, with the aim of helping clinicians make an accurate diagnosis of infectious myocarditis.

MicroRNA-22-3p displaces critical host factors from the 5' UTR and inhibits the translation of Coxsackievirus B3 RNA

Coxsackievirus B3 (CVB3) is known to cause acute myocarditis and pancreatitis in humans. We investigated the microRNAs (miRNAs) that can potentially govern the viral life cycle by binding to the untranslated regions (UTRs) of CVB3 RNA. MicroRNA-22-3p was short-listed, as its potential binding site overlapped with the region crucial for recruiting internal ribosome entry site trans-acting factors (ITAFs) and ribosomes. We demonstrate that miR-22-3p binds CVB3 5' UTR, hinders recruitment of key ITAFs on viral mRNA, disrupts the spatial structure required for ribosome recruitment, and ultimately blocks translation. Likewise, cells lacking miR-22-3p exhibited heightened CVB3 infection compared to wild type, confirming its role in controlling infection. Interestingly, miR-22-3p level was found to be increased at 4 hours post-infection, potentially due to the accumulation of viral 2A protease in the early phase of infection. 2Apro enhances the miR-22-3p level to dislodge the ITAFs from the SD-like sequence, rendering the viral RNA accessible for binding of replication factors to switch to replication. Furthermore, one of the cellular targets of miR-22-3p, protocadherin-1 (PCDH1), was significantly downregulated during CVB3 infection. Partial silencing of PCDH1 reduced viral replication, demonstrating its proviral role. Interestingly, upon CVB3 infection in mice, miR-22-3p level was found to be downregulated only in the small intestine, the primary target organ, indicating its possible role in influencing tissue tropism. It appears miR-22-3p plays a dual role during infection by binding viral RNA to aid its life cycle as a viral strategy and by targeting a proviral protein to restrict viral replication as a host response.IMPORTANCECVB3 infection is associated with the development of end-stage heart diseases. Lack of effective anti-viral treatments and vaccines for CVB3 necessitates comprehensive understanding of the molecular players during CVB3 infection. miRNAs have emerged as promising targets for anti-viral strategies. Here, we demonstrate that miR-22-3p binds to 5' UTR and inhibits viral RNA translation at the later stage of infection to promote viral RNA replication. Conversely, as host response, it targets PCDH1, a proviral factor, to discourage viral propagation. miR-22-3p also influences CVB3 tissue tropism. Deciphering the multifaced role of miR-22-3p during CVB3 infection unravels the necessary molecular insights, which can be exploited for novel intervening strategies to curb infection and restrict viral pathogenesis.

Action mechanisms and characteristics of miRNAs to regulate virus replication

MicroRNAs (miRNAs) have the potential to be explored as antiviral products. It is known that miRNAs have different kinds of target mRNAs and different target sites in mRNAs, and that the action-modes of miRNAs at different target sites may be different. But there is no evidence demonstrating the significance of the differences for the regulation of viruses by miRNAs, which might be crucial for the exploration of miRNA-based antiviral products. Here the experimental studies about the antiviral effects of miRNAs, with validated target mRNAs and target sites in the mRNAs, were systematically collected, based on which the mechanisms whereby miRNAs regulated virus replication were systematically reviewed. And miRNAs' down-regulation rates on target mRNAs and antiviral rates were compared among the miRNAs with different target sites, to analyze the characteristics of action-modes of miRNAs at different target sites during virus replication.

MicroRNAs in Myocarditis-Review of the Preclinical In Vivo Trials

Myocarditis is an inflammatory heart disease with viruses as the most common cause. Regardless of multiple studies that have recently been conducted, the diagnostic options still need to be improved. Although endomyocardial biopsy is known as a diagnostic gold standard, it is invasive and, thus, only sometimes performed. Novel techniques of cardiac magnetic resonance are not readily available. Therapy in viral infections is based mainly on symptomatic treatment, while steroids and intravenous immunoglobulins are used in autoimmune myocarditis. The effectiveness of neither of these methods has been explicitly proven to date. Therefore, novel diagnostic and therapeutic strategies are highly needed. MiRNAs are small, non-coding molecules that regulate fundamental cell functions, including differentiation, metabolism, and apoptosis. They present altered levels in different diseases, including myocarditis. Numerous studies investigating the role of miRNAs in myocarditis have already been conducted. In this review, we discussed only the original preclinical in vivo research. We eventually included 30 studies relevant to the discussed area. The altered miRNA levels have been observed, including upregulation and downregulation of different miRNAs in the mice models of myocarditis. Furthermore, the administration of mimics or inhibitors of particular miRNAs was shown to significantly influence inflammation, morphology, and function of the heart and overall survival. Finally, some studies presented prospective advantages in vaccine development.

MicroRNA delivery based on nanoparticles of cardiovascular diseases

Cardiovascular disease, especially myocardial infarction, is a serious threat to human health. Many drugs currently used cannot achieve the desired therapeutic effect due to the lack of selectivity. With the in-depth understanding of the role of microRNA (miRNA) in cardiovascular disease and the wide application of nanotechnology, loading drugs into nanoparticles with the help of nano-delivery system may have a better effect in the treatment of cardiomyopathy. In this review, we highlight the latest research on miRNAs in the treatment of cardiovascular disease in recent years and discuss the possibilities and challenges of using miRNA to treat cardiomyopathy. Secondly, we discuss the delivery of miRNA through different nano-carriers, especially inorganic, polymer and liposome nano-carriers. The preparation of miRNA nano-drugs by encapsulating miRNA in these nano-materials will provide a new treatment option. In addition, the research status of miRNA in the treatment of cardiomyopathy based on nano-carriers is summarized. The use of this delivery tool cannot only realize therapeutic potential, but also greatly improve drug targeting and reduce side effects.

Potential of MicroRNAs As Biomarkers and Therapeutic Targets in Respiratory Viruses: A Literature Review

MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression through recognition of cognate sequences and interference of transcriptional, translational, or epigenetic processes. Hundreds of miRNA genes have been found in diverse viruses, and many of these are phylogenetically conserved. Respiratory viruses are the most frequent causative agents of disease in humans, with a significant impact on morbidity and mortality worldwide. Recently, the role of miRNAs in respiratory viral gene regulation, as well as host gene regulation during disease progression, has become a field of interest. This review highlighted the importance of various miRNAs and their potential role in fighting with respiratory viruses as therapeutic molecules with a focus on COVID-19.

MicroRNA-30a-5p silencing polarizes macrophages toward M2 phenotype to alleviate cardiac injury following viral myocarditis by targeting SOCS1

Viral myocarditis (VMC) is a life-threatening disease characterized by severe cardiac inflammation generally caused by coxsackievirus B3 (CVB3) infection. Several microRNAs (miRNAs or miRs) are known to play crucial roles in the pathogenesis of VMC. The study aimed to decipher the role of miR-30a-5p in the underlying mechanisms of VMC pathogenesis. We first quantified miR-30a-5p expression in a CVB3-induced mouse VMC model. The physiological characteristics of mouse cardiac tissues were then detected by hematoxylin and eosin (HE) and Picrosirius red staining. We established the correlation between miR-30a-5p and SOCS1, using dual-luciferase gene assay and Pearson's correlation coefficient. The expression of inflammatory factors (IFN-γ, IL-6, IL-10, and IL-13), M1 polarization markers [TNF-α, inducible nitric oxide synthase (iNOS)], M2 polarization markers (Arg-1, IL-10), and myocardial hypertrophy markers [atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP)] was detected by RT-qPCR and Western blot analysis. miR-30a-5p was found to be highly expressed in VMC mice. Silencing of miR-30a-5p improved the cardiac function index and reduced heart weight-to-body weight ratio, myocardial tissue pathological changes and fibrosis degree, serological indexes, as well as proinflammatory factor levels, while enhancing anti-inflammatory factor levels in VMC mice. Furthermore, silencing of miR-30a-5p inhibited M1 polarization of macrophages while promoting M2 polarization in vivo and in vitro. SOCS1 was a target gene of miR-30a-5p, and the aforementioned cardioprotective effects of miR-30a-5p silencing were reversed upon silencing of SOCS1. Overall, this study shows that silencing of miR-30a-5p may promote M2 polarization of macrophages and improve cardiac injury following VMC via SOCS1 upregulation, constituting a potential therapeutic target for VMC treatment.NEW & NOTEWORTHY We found in this study that microRNA (miR)-30a-5p inhibition might improve cardiac injury following viral myocarditis (VMC) by accelerating M2 polarization of macrophages via SOCS1 upregulation. Furthermore, the anti-inflammatory mechanisms of miR-30a-5p inhibition may contribute to the development of new therapeutic strategies for VMC.

Essential Role of Non-Coding RNAs in Enterovirus Infection: From Basic Mechanisms to Clinical Prospects

Enteroviruses (EVs) are common RNA viruses that can cause various types of human diseases and conditions such as hand, foot, and mouth disease (HFMD), myocarditis, meningitis, sepsis, and respiratory disorders. Although EV infections in most patients are generally mild and self-limiting, a small number of young children can develop serious complications such as encephalitis, acute flaccid paralysis, myocarditis, and cardiorespiratory failure, resulting in fatalities. Established evidence has suggested that certain non-coding RNAs (ncRNAs) such as microRNAs (miRNAs), long ncRNAs (lncRNAs), and circular RNAs (circRNAs) are involved in the occurrence and progression of many human diseases. Recently, the involvement of ncRNAs in the course of EV infection has been reported. Herein, the authors focus on recent advances in the understanding of ncRNAs in EV infection from basic viral pathogenesis to clinical prospects, providing a reference basis and new ideas for disease prevention and research directions.

Weighted gene co-expression network analysis identified underlying hub genes and mechanisms in the occurrence and development of viral myocarditis

Background

Myocarditis is an inflammatory myocardial disease, which may lead to heart failure and sudden death. Despite extensive research into the pathogenesis of myocarditis, effective treatments for this condition remain elusive. This study aimed to explore the potential pathogenesis and hub genes for viral myocarditis.

Methods

A weighted gene co-expression network analysis (WGCNA) was performed based on the gene expression profiles derived from mouse models at different stages of viral myocarditis (GSE35182). Functional annotation was executed within the key modules. Potential hub genes were predicted based on the intramodular connectivity (IC). Finally, potential microRNAs that regulate gene expression were predicted by miRNet analysis.

Results

Three gene co-expression modules showed the strongest correlation with the acute or chronic disease stage. A significant positive correlation was detected between the acute disease stage and the turquoise module, the genes of which were mainly enriched in antiviral response and immune-inflammatory activation. Furthermore, a significant positive correlation and a negative correlation were identified between the chronic disease stage and the brown and yellow modules, respectively. These modules were mainly associated with the cytoskeleton, phosphorylation, cellular catabolic process, and autophagy. Subsequently, we predicted the underlying hub genes and microRNAs in the three modules.

Conclusions

This study revealed the main biological processes in different stages of viral myocarditis and predicted hub genes in both the acute and chronic disease stages. Our results may be helpful for developing new therapeutic targets for viral myocarditis in future research.

Advancement of Mechanisms of Coxsackie Virus B3-Induced Myocarditis Pathogenesis and the Potential Therapeutic Targets

Viral myocarditis is a cardiac disease caused by Group B Coxsackie virus of Enterovirus genus in the Picorna viridae family. It causes heart failure in children, young and adults. Ten Percent (10%) of acute heart failure and 12% of sudden deaths in young and adults who are less than 40 years is due to this viral myocarditis. If treatment action is not taken earlier, the viral disease can develop into chronic myocarditis and Dilated Cardiomyopathy which lead to congestive heart failure. And these eventually result in a reduced cardiac function which finally brings the victim to death. The only treatment option of the disease is heart transplantation once the acute stage of disease develops to chronic and Dilated Cardiomyopathy. Currently, there is a limitation in daily clinical treatments and even some available treatment options are ineffective. Therefore, focusing on search for treatment options through investigation is imperative. Recent studies have reported that biological molecules show a promising role. But their mechanism of pathogenesis is still unclear. A detailed study on identifying the role of biological molecules involved in Coxsackie B3 virus induced myocarditis and their mechanisms of pathogenesis; compiling and disseminating the findings of the investigation to the scientific communities contribute one step forward to the solution. Therefore, this review is aimed at compiling information from findings of current studies on the potential therapeutic role of micro RNA, cytokines and chemokines on the mechanism of pathogenesis of Coxsackie virus B3- induced myocarditis to give brief information for scholars to conduct a detailed study in the area.

The Role of Non-coding RNAs in Viral Myocarditis

Viral myocarditis (VMC) is a disease characterized as myocardial parenchyma or interstitium inflammation caused by virus infection, especially Coxsackievirus B3 (CVB3) infection, which has no accurate non-invasive examination for diagnosis and specific drugs for treatment. The mechanism of CVB3-induced VMC may be related to direct myocardial damage of virus infection and extensive damage of abnormal immune response after infection. Non-coding RNA (ncRNA) refers to RNA that is not translated into protein and plays a vital role in many biological processes. There is expanding evidence to reveal that ncRNAs regulate the occurrence and development of VMC, which may provide new treatment or diagnosis targets. In this review, we mainly demonstrate an overview of the potential role of ncRNAs in the pathogenesis, diagnosis and treatment of CVB3-induced VMC.

Dysregulated CD4+ T Cells and microRNAs in Myocarditis

Myocarditis is a polymorphic disease complicated with indeterminate etiology and pathogenesis, and represents one of the most challenging clinical problems lacking specific diagnosis and effective therapy. It is caused by a complex interplay of environmental and genetic factors, and causal links between dysregulated microribonucleic acids (miRNAs) and myocarditis have also been supported by recent epigenetic researches. Both dysregulated CD4+ T cells and miRNAs play critical roles in the pathogenesis of myocarditis, and the classic triphasic model of its pathogenesis consists of the acute infectious, subacute immune, and recovery/chronic myopathic phase. CD4+ T cells are key pathogenic factors underlying the development and progression of myocarditis, and the effector and regulatory subsets, respectively, promote and inhibit autoimmune responses. Furthermore, the reciprocal interplay of these subsets influences the pathogenesis as well. Dysregulated miRNAs along with their mRNA and protein targets have been identified in heart biopsies (intracellular miRNAs) and body fluids (circulating miRNAs) during myocarditis. These miRNAs show phase-dependent changes, and correlate with viral infection, immune status, fibrosis, destruction of cardiomyocytes, arrhythmias, cardiac functions, and outcomes. Thus, miRNAs are promising diagnostic markers and therapeutic targets in myocarditis. In this review, we review myocarditis with an emphasis on its pathogenesis, and present a summary of current knowledge of dysregulated CD4+ T cells and miRNAs in myocarditis.

Genetic Basis of Myocarditis: Myth or Reality?

The genetic basis of myocarditis remains an intriguing concept, at least as long as the definition of myocarditis constitutes the definitive presence of myocardial inflammation sufficient to cause the observed ventricular dysfunction in the setting of cardiotropic infections. Autoimmune or immune-mediated myocardial inflammation constitutes a complex area of clinical interest, wherein numerous and not yet fully understood role of hereditary auto-inflammatory diseases can result in inflammation of the pericardium and myocardium. Finally, myocardial involvement in hereditary immunodeficiency diseases, cellular and humoral, is a possible trigger for infections which may complicate the diseases themselves. Whether the role of constitutional genetics can make the patient susceptible to myocardial inflammation remains yet to be explored.

Construction of miRNA-target networks using microRNA profiles of CVB3-infected HeLa cells

MicroRNAs (miRNAs) play an important role in regulating gene expression in multiple biological processes and diseases. Thus, to understand changes in miRNA during CVB3 infection, specific miRNA expression profiles were investigated at 3 h, 6 h, and 9 h postinfection in HeLa cells by small-RNA high-throughput sequencing. Biological implications of 68 differentially expressed miRNAs were analyzed through GO and KEGG pathways. Interaction networks between 34 known highly differentially expressed miRNAs and targets were constructed by mirDIP and Navigator. The predicted targets showed that FAM135A, IKZF2, PLAG1, ZNF148, PHC3, LCOR and DYRK1A, which are associated with cellular differentiation and transcriptional regulation, were recognized by 8 miRNAs or 9 miRNAs through interactional regulatory networks. Seven target genes were confirmed by RT-qPCR. The results showed that the expression of DYRK1A, FAM135A, PLAG1, ZNF148, and PHC3 were obviously inhibited at 3 h, 6 h, and 9 h postinfection. The expression of LCOR did not show a significant change, and the expression of IKZF2 increased gradually with prolonged infection time. Our findings improve the understanding of the pathogenic mechanism of CVB3 infection on cellular differentiation and development through miRNA regulation, which has implications for interventional approaches to CVB3-infection therapy. Our results also provide a new method for screening target genes of microRNA regulation in virus-infected cells.

MicroRNAs in Inflammatory Heart Diseases and Sepsis-Induced Cardiac Dysfunction: A Potential Scope for the Future?

Background: MicroRNAs (miRNAs) are small, single-stranded RNA sequences that regulate gene expression on a post-transcriptional level. In the last few decades, various trials have investigated the diagnostic and therapeutic potential of miRNAs in several disease entities. Here, we provide a review of the available evidence on miRNAs in inflammatory heart diseases (myocarditis, endocarditis, and pericarditis) and sepsis-induced cardiac dysfunction. Methods: Systematic database research using the PubMed and Medline databases was conducted between July and September 2019 using predefined search terms. The whole review was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Results: In total, 131 studies were screened, 96 abstracts were read, and 69 studies were included in the review. Discussion: In the future, circulating miRNAs could serve as biomarkers for diagnosis and disease monitoring in the context of inflammatory heart diseases and sepsis-induced cardiac dysfunction. Considering the promising results of different animal models, certain miRNAs could also emerge as novel therapeutic approaches in this setting.

miRNAs in enterovirus infection

During the last years, it has become evident that miRNAs are important players in almost all physiological and pathological processes, including viral infections. Enterovirus infections range from mild to severe acute infections concerning several organ systems and are also associated with chronic diseases. In this review, we summarize the findings on the impact of acute and persistent enterovirus infection on the expression of cellular miRNAs. Furthermore, the currently available data on the regulation of cellular or viral targets by the dysregulated miRNAs are reviewed. Finally, a translational perspective, namely the use of miRNAs as biomarkers of enterovirus infection and as antiviral strategy is discussed.

Up-regulation of microRNA-203 in influenza A virus infection inhibits viral replication by targeting DR1

MicroRNAs (miRNAs) are small noncoding RNA molecules that play important roles in various biological processes. Much evidence shows that miRNAs are closely associated with numerous virus infections; however, involvement of cellular miRNAs in influenza A virus (IAV) infection is unclear. Here, we found that expression of miR-203 was up-regulated markedly via two different mechanisms during IAV infection. First, we examined the effects of type I interferon induced by IAV on direct activation of miR-203 expression. Next, we showed that DNA demethylation within the miR-203 promoter region in A549 cells induced its up-regulation, and that expression of DNA methyltransferase 1 was down-regulated following H5N1 virus infection. Ectopic expression of miR-203 in turn inhibited H5N1 virus replication by targeting down-regulator of transcription 1 (DR1), which was identified as a novel target of miR-203. Silencing DR1 in miR-203 knockout cells using a specific siRNA inhibited replication of the H5N1 virus, an effect similar to that of miR-203. In summary, the data show that host cell expression of miR-203 is up-regulated upon IAV infection, which increases antiviral responses by suppressing a novel target gene, DR1. Thus, we have identified a novel mechanism underlying the relationship between miR-203 and IAV infection.

Detecting TF-miRNA-gene network based modules for 5hmC and 5mC brain samples: a intra- and inter-species case-study between human and rhesus

Background

Study of epigenetics is currently a high-impact research topic. Multi stage methylation is also an area of high-dimensional prospect. In this article, we provide a new study (intra and inter-species study) on brain tissue between human and rhesus on two methylation cytosine variants based data-profiles (viz., 5-hydroxymethylcytosine (5hmC) and 5-methylcytosine (5mC) samples) through TF-miRNA-gene network based module detection.

Results

First of all, we determine differentially 5hmC methylated genes for human as well as rhesus for intra-species analysis, and differentially multi-stage methylated genes for inter-species analysis. Thereafter, we utilize weighted topological overlap matrix (TOM) measure and average linkage clustering consecutively on these genesets for intra- and inter-species study.We identify co-methylated and multi-stage co-methylated gene modules by using dynamic tree cut, for intra-and inter-species cases, respectively. Each module is represented by individual color in the dendrogram. Gene Ontology and KEGG pathway based analysis are then performed to identify biological functionalities of the identified modules. Finally, top ten regulator TFs and targeter miRNAs that are associated with the maximum number of gene modules, are determined for both intra-and inter-species analysis.

Conclusions

The novel TFs and miRNAs obtained from the analysis are: MYST3 and ZNF771 as TFs (for human intra-species analysis), BAZ2B, RCOR3 and ATF1 as TFs (for rhesus intra-species analysis), and mml-miR-768-3p and mml-miR-561 as miRs (for rhesus intra-species analysis); and MYST3 and ZNF771 as miRs(for inter-species study). Furthermore, the genes/TFs/miRNAs that are already found to be liable for several brain-related dreadful diseases as well as rare neglected diseases (e.g., wolf Hirschhorn syndrome, Joubarts Syndrome, Huntington’s disease, Simian Immunodeficiency Virus(SIV) mediated enchaphilits, Parkinsons Disease, Bipolar disorder and Schizophenia etc.) are mentioned.

Electronic supplementary material

The online version of this article (doi:10.1186/s12863-017-0574-7) contains supplementary material, which is available to authorized users.

MicroRNA-20b suppresses the expression of ZFP-148 in viral myocarditis

Viral myocarditis is a common cardiovascular disease, which seriously endangers the health of people and even leads to sudden unexpected death. MicroRNAs play very important roles in various physical and pathological processes including cardiogenesis and heart diseases. In recent years, miR-20b has been implicated in various diseases such as breast cancer, gastric cancer, hepatocellular carcinoma, cardiovascular diseases. However, the function of miR-20b in the pathological progress of viral myocarditis has not been reported. In this study, we found that miR-20b was up-regulated in mouse heart tissues post Coxsackievirus B3 (CVB3) infection. Bioinformatics analysis identified ZFP-148, a transcription factor that plays essential roles in the regulation of virus replication, is one of the predicted targets of miR-20b. MiR-20b expression was found to be up-regulated and ZFP-148 protein level was markedly repressed during viral myocarditis. Further studies demonstrated that miR-20b directly binds to the 3'-UTR of ZFP-148 and suppresses its translation. Moreover, aberrant expression of miR-20b promoted the expression of anti-apoptosis proteins Bcl-2 and Bcl-xL, suggesting that altered gene expression might promote cardiomyocytes survival in viral myocarditis. Our findings indicated that miR-20b might be a potential therapeutic target for CVB3-induced viral myocarditis and a useful marker for the diagnosis of viral myocarditis.

MicroRNAs in Type 1 Diabetes: Complex Interregulation of the Immune System, β Cell Function and Viral Infections

Since the discovery of the first mammalian microRNA (miRNA) more than two decades ago, a plethora of miRNAs has been identified in humans, now amounting to more than 2500. Essential for post-transcriptional regulation of gene networks integral for developmental pathways and immune response, it is not surprising that dysregulation of miRNAs is often associated with the aetiology of complex diseases including cancer, diabetes and autoimmune disorders. Despite massive expansion of small RNA studies and extensive investigation in diverse disease contexts, the role of miRNAs in type 1 diabetes has only recently been explored. Key studies using human islets have recently implicated virus-induced miRNA dysregulation as a pivotal mechanism of β cell destruction, while the interplay between miRNAs, the immune system and β cell survival has been illustrated in studies using animal and cellular models of disease. The role of specific miRNAs as major players in immune system homeostasis highlights their exciting potential as therapeutics and prognostic biomarkers of type 1 diabetes.

Microarray analysis reveals altered circulating microRNA expression in mice infected with Coxsackievirus B3

Coxsackievirus B3 (CVB3) is a common causative agent in the development of inflammatory cardiomyopathy. However, whether the expression of peripheral blood microRNAs (miRNAs) is altered in this process is unknown. The present study investigated changes to miRNA expression in the peripheral blood of CVB3-infected mice. Utilizing miRNA microarray technology, differential miRNA expression was examined between normal and CVB3-infected mice. The present results suggest that specific miRNAs were differentially expressed in the peripheral blood of mice infected with CVB3, varying with infection duration. Using miRNA microarray analysis, a total of 96 and 89 differentially expressed miRNAs were identified in the peripheral blood of mice infected with CVB3 for 3 and 6 days, respectively. Quantitative polymerase chain reaction was used to validate differentially expressed miRNAs, revealing a consistency of these results with the miRNA microarray analysis results. The biological functions of the differentially expressed miRNAs were then predicted by bioinformatics analysis. The potential biological roles of differentially expressed miRNAs included hypertrophic cardiomyopathy, dilated cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy. These results may provide important insights into the mechanisms responsible for the progression of CVB3 infection.

What Is the Arrhythmic Substrate in Viral Myocarditis? Insights from Clinical and Animal Studies

Sudden cardiac death (SCD) remains an unsolved problem in the twenty-first century. It is often due to rapid onset, ventricular arrhythmias caused by a number of different clinical conditions. A proportion of SCD patients have identifiable diseases such as cardiomyopathies, but for others, the causes are unknown. Viral myocarditis is becoming increasingly recognized as a contributor to unexplained mortality, and is thought to be a major cause of SCD in the first two decades of life. Myocardial inflammation, ion channel dysfunction, electrophysiological, and structural remodeling may play important roles in generating life-threatening arrhythmias. The aim of this review article is to examine the electrophysiology of action potential conduction and repolarization and the mechanisms by which their derangements lead to triggered and reentrant arrhythmogenesis. By synthesizing experimental evidence from pre-clinical and clinical studies, a framework of how host (inflammation), and viral (altered cellular signaling) factors can induce ion electrophysiological and structural remodeling is illustrated. Current pharmacological options are mainly supportive, which may be accompanied by mechanical circulatory support. Heart transplantation is the only curative option in the worst case scenario. Future strategies for the management of viral myocarditis are discussed.

Myocarditis

Viral myocarditis remains a prominent infectious-inflammatory disease for patients throughout the lifespan. The condition presents several challenges including varied modes of clinical presentation, a range of timepoints when patients come to attention, a diversity of approaches to diagnosis, a spectrum of clinical courses, and unsettled perspectives on therapeutics in different patient settings and in the face of different viral pathogens. In this review, we examine current knowledge about viral heart disease and especially provide information on evolving understanding of mechanisms of disease and efforts by investigators to identify and evaluate potential therapeutic avenues for intervention.

Endomyocardial miR-133a levels correlate with myocardial inflammation, improved left ventricular function, and clinical outcome in patients with inflammatory cardiomyopathy

AIMS

Inflammatory heart disease represents an important cause of chronic dilated cardiomyopathy (DCM). Predicting the clinical course of patients with inflammatory cardiomyopathy (iCMP) is difficult, and the prognostic value of current biological markers remains controversial. We tested whether expression of selected microRNAs in endomyocardial biopsies (EMBs) is related to LV functional recovery and clinical events in iCMP patients.

METHODS AND RESULTS

EMBs were obtained from patients with iCMP (n = 76) and non-inflammatory DCM (n = 22). A set of six microRNAs implicated in inflammation (miR-155 and miR-146b), heart failure (miR-21 and miR-133a), and endothelial cell (miR-126) and skeletal muscle function (miR-206) was pre-defined. Endomyocardial expression of miR-155 and miR-133a, as quantified by reverse transcription-PCR (RT-PCR), was up-regulated in patients with iCMP as compared with patients with DCM. Levels of miR-133a (R = 0.73, P < 0.01) and miR-155 (R = 0.63, P < 0.01) correlated with inflammatory cell count on EMBs from patients with iCMP. Patients with iCMP and preserved LV function at study entry demonstrated higher expression of miR-133a than patients with reduced LV function. Also, increased expression of miR-133a was associated with less fibrosis and myocyte necrosis on EMB, and LV functional recovery during a mean follow-up of 3.1 years. Importantly, patients with iCMP and miR-133a levels in the upper tertile showed longer survival free of death, malignant arrhythmias, and hospitalizations for heart failure.

CONCLUSION

The present study demonstrates that miR-133a levels correlate with macrophage infiltration, cardiac injury, improved LV function, and clinical outcome in patients with iCMP. miR-133a may serve as a potential novel biomarker and therapeutic target in human iCMP.

MicroRNA and Pathogenesis of Enterovirus Infection

There are no currently available specific antiviral therapies for non-polio Enterovirus infections. Although several vaccines have entered clinical trials, the efficacy requires further evaluation, particularly for cross-strain protective activity. Curing patients with viral infections is a public health problem due to antigen alterations and drug resistance caused by the high genomic mutation rate. To conquer these limits in the development of anti-Enterovirus treatments, a comprehensive understanding of the interactions between Enterovirus and host cells is urgently needed. MicroRNA (miRNA) constitutes the biggest family of gene regulators in mammalian cells and regulates almost a half of all human genes. The roles of miRNAs in Enterovirus pathogenesis have recently begun to be noted. In this review, we shed light on recent advances in the understanding of Enterovirus infection-modulated miRNAs. The impacts of altered host miRNAs on cellular processes, including immune escape, apoptosis, signal transduction, shutdown of host protein synthesis and viral replication, are discussed. Finally, miRNA-based medication provides a promising strategy for the development of antiviral therapy.

Emodin inhibits coxsackievirus B3 replication via multiple signalling cascades leading to suppression of translation

CVB3 (coxsackievirus 3) is a primary causal agent of viral myocarditis. Emodin is a natural compound isolated from certain plant roots. In the present study, we found that emodin inhibited CVB3 replication in vitro and in mice, and now we report an unrecognized mechanism by which emodin inhibits CVB3 replication through suppression of viral protein translation via multiple pathways. On one hand, emodin treatment inhibited Akt/mTOR (mammalian target of rapamycin) signalling and activated 4EBP1 (eukaryotic initiation factor 4R-binding protein 1), leading to suppression of translation initiation of ribosomal protein L32 encoded by a 5'-TOP (terminal oligopyrimidine) mRNA. On the other hand, emodin treatment differentially regulated multiple signal cascades, including Akt/mTORC1/p70(S6K) (p70 S6 kinase), ERK1/2 (extracellular-signal-regulated kinase 1/2)/p90(RSK) (p90 ribosomal S6 kinase) and Ca(2+)/calmodulin, leading to activation of eEF2K (eukaryotic elongation factor 2 kinase) and subsequent inactivation of eEF2 (eukaryotic elongation factor 2), resulting in inhibition of CVB3 VP1 (viral protein 1) synthesis. These data imply that eEF2K is a major factor mediating cross-talk of different arms of signalling cascades in this signal network. This notion was verified by either overexpressing eEF2K or treating the cells with siRNAs or eEF2K inhibitor A484954. We showed further that the emodin-induced decrease in p70(S6K) phosphorylation plays a dominant positive role in activation of eEF2K and in turn in conferring the antiviral effect of emodin. This finding was further solidified by expressing constitutively active and dominant-negative Akt. Collectively, our data reveal that emodin inhibits viral replication through impairing translational machinery and suppression of viral translation elongation.

The role of microRNAs in enteroviral infections

The genus Enterovirus, a member of the Picornavirus family, are RNA viruses that can cause poliomyelitis, hand-food-mouth disease, viral meningitis or meningoencephalitis, viral myocarditis and so on. MicroRNAs are a class of highly conserved, small noncoding RNAs recognized as important regulators of gene expression. Recent studies found that MicroRNAs play a significant role in the infection of Enterovirus, such as enterovirus 71, coxsackievirus B3 and other Enterovirus. Enteroviral infection can alter the expression of cellular MicroRNAs, and cellular MicroRNAs can modulate viral pathogenesis and replication by regulating the expression level of viral or host's genes. Herein, this review summarizes the role of MicroRNAs in enteroviral infection.

miR-203 downregulates Yes-1 and suppresses oncogenic activity in human oral cancer cells

The purpose of this study was to elucidate the molecular mechanisms of microRNA-203 (miR-203) as a tumor suppressor in KB human oral cancer cells. MicroRNA microarray results showed that the expression of miR-203 was significantly down-regulated in KB cells compared with normal human oral keratinocytes. The viability of KB cells was decreased by miR-203 in the time- and dose-dependent manners. In addition, over-expressed miR-203 not only increased the nuclear condensation but also significantly increased the apoptotic population of KB cells. These results indicated that the over-expression of miR-203 induced apoptosis of KB cells. Furthermore, the target gene array analyses revealed that the expression of Yes-1, a member of the Src family kinases (SFKs), was significantly down-regulated by miR-203 in KB cells. Moreover, both the mRNA and protein levels of Yes-1 were strongly reduced in KB cells transfected with miR-203. Therefore, these results indicated that Yes-1 is predicted to be a potential target gene of miR-203. Through a luciferase activity assay, miR-203 was confirmed to directly targets the Yes-1 3' untranslated region (UTR) to suppress gene expression. Therefore, our findings indicate that miR-203 induces the apoptosis of KB cells by directly targeting Yes-1, suggesting its application in anti-cancer therapeutics.

Coxsackievirus B3 replication and pathogenesis

ABSTRACT 

Viruses such as coxsackievirus B3 (CVB3) are entirely host cell-dependent parasites. Indeed, they must cleverly exploit various compartments of host cells to complete their life cycle, and consequently launch disease. Evolution has equipped this pico-rna-virus, CVB3, to use different strategies, including CVB3-induced direct damage to host cells followed by a host inflammatory response to CVB3 infection, and cell death to super-additively promote target organ tissue injury, and dysfunction. In this update, the patho-stratagems of CVB3 are explored from molecular, and systems-level approaches. In summarizing recent developments in this field, we focus particularly on mechanisms by which CVB3 can harness different host cell processes including kinases, host cell-killing and cell-eating machineries, matrix metalloproteinases and miRNAs to promote disease.

Upregulated microRNA-214 enhances cardiac injury by targeting ITCH during coxsackievirus infection

Viral myocarditis (VM), a severe clinical condition characterized by cardiac inflammation, is most frequently induced as a result of coxsackievirus infection. Evidence suggests that microRNAs may have significant roles in the progression of cardiac injury during coxsackievirus infection. Concurrently, microRNA (miR)-214 was found to be upregulated in the plasma and myocardial cells during this process. In the present study, eight candidate miRNAs, the functions of which are associated with myocarditis, were selected and their expression levels were evaluated by reverse transcription-quantitative polymerase chain reaction. miR-146b and miR-214 were found to have significantly upregulated expression levels in the heart tissues of patients with VM compared with those of the control subjects. Predictions via the use of online bioinformatics tools and confirmed by dual-luciferase assay and western blot analysis, revealed that ITCH, an NF-κB signaling suppressor, was a target gene of miR-214. To investigate the biological function of miR-214, tumor necrosis factor-α and interleukin-6 expression levels were evaluated in HeLa cell culture supernatant. The results revealed that miR-214 overexpression enhanced the expression of the two cytokines. In addition, the function of miR-214 was partially rescued by ITCH overexpression. Subsequently, concurrent results were obtained following experiments in murine cardiac myocytes. In conclusion, the results of the present study demonstrated that miR-214 contributed to the adverse inflammatory response to viral infection of the heart during coxsackievirus infection and is therefore a potential therapeutic target for the treatment of viral myocarditis.

Differential Cardiac MicroRNA Expression Predicts the Clinical Course in Human Enterovirus Cardiomyopathy

BACKGROUND

Investigation of disease pathogenesis confined to protein-coding regions of the genome may be incomplete because many noncoding variants are associated with disease. We aimed to identify novel predictive markers for the course of enterovirus (CVB3) cardiomyopathy by screening for noncoding elements influencing the grossly different antiviral capacity of individual patients.

METHODS AND RESULTS

Transcriptome mapping of CVB3 cardiomyopathy patients revealed distinctive cardiac microRNA (miR) patterns associated with spontaneous virus clearance and recovery (CVB3-ELIM) versus virus persistence and progressive clinical deterioration (CVB3-PERS). Profiling of protein-coding genes and 754 miRs in endomyocardial biopsies of test cohorts was performed at their initial presentation, and those spontaneously eliminating the virus were compared with those with virus persistence on follow-up. miR profiling revealed highly significant differences in cardiac levels of 16 miRs, but not of protein-coding genes. Evaluation of this primary distinctive miR pattern in validation cohorts, and multivariate receiver operating characteristic curve analysis, confirmed this pattern as highly predictive for disease course (area under the curve, 0.897±0.071; 95% confidence interval, 0.758-1.000). Eight miRs were strongly induced in CVB3-PERS (miRs 135b, 155, 190, 422a, 489, 590, 601, 1290), but undetectable in CVB3-ELIM or controls. They are predicted to target multiple immune response genes, and 2 of these were confirmed by antisense-mediated ablation of miRs 135b, 190, and 422a in the monocytic THP-1 cell line.

CONCLUSIONS

An immediate clinical application of the data is cardiac miR profiling to assess the risk of virus persistence and progressive clinical deterioration in CVB3 cardiomyopathy. Patients at risk are eligible for immediate antiviral therapy to minimize irreversible cardiac damage.

Cellular microRNAs and picornaviral infections

microRNAs (miRNAs) are a subtype of short, endogenous, and non-coding RNAs, which post-transcriptionally regulate gene expression. The miRNA-mediated gene silencing mechanism is involved in a wide spectrum of biological processes, such as cellular proliferation, differentiation, and immune responses. Picornaviridae is a large family of RNA viruses, which includes a number of causative agents of many human and animal diseases viz., poliovirus, foot-and-mouth disease virus (FMDV), and coxsackievirus B3 (CVB3). Accumulated evidences have demonstrated that replication of picornaviruses can be regulated by miRNAs and picornaviral infections can alter the expression of cellular miRNAs. Herein, we outline the intricate interactions between miRNAs and picornaviral infections.

Coxsackievirus-induced miR-21 disrupts cardiomyocyte interactions via the downregulation of intercalated disk components

Intercalated disks (ICDs) are substantial connections maintaining cardiac structures and mediating signal communications among cardiomyocytes. Deficiency in ICD components such as desmosomes, fascia adherens and gap junctions leads to heart dysfunction. Coxsackievirus B3 (CVB3) infection induces cardiac failure but its pathogenic effect on ICDs is unclear. Here we show that CVB3-induced miR-21 expression affects ICD structure, i.e., upregulated miR-21 targets YOD1, a deubiquitinating enzyme, to enhance the K48-linked ubiquitination and degradation of desmin, resulting in disruption of desmosomes. Inhibition of miR-21 preserves desmin during CVB3 infection. Treatment with proteasome inhibitors blocks miR-21-mediated desmin degradation. Transfection of miR-21 or knockdown of YOD1 triggers co-localization of desmin with proteasomes. We also identified K108 and K406 as important sites for desmin ubiquintination and degradation. In addition, miR-21 directly targets vinculin, leading to disturbed fascia adherens evidenced by the suppression and disorientation of pan-cadherin and α-E-catenin proteins, two fascia adherens-components. Our findings suggest a new mechanism of miR-21 in modulating cell-cell interactions of cardiomyocytes during CVB3 infection.

Coxsackievirus B3 (CVB3) is one of most common causes of heart inflammation and failure. However, the mechanism by which CVB3 induces cardiac damage has not been fully elucidated. Particularly, the involvement of microRNAs (miRNAs), a family of small RNAs controlling the progression of a wide range of diseases, in CVB3 infection is still unclear. These small RNAs are essential to understand the CVB3-caused heart muscle cell injury and have great potential to serve therapeutic purposes. Here, we systematically analyzed the miRNA changes during CVB3 infection and found that miR-21 is increased by viral infection. We further demonstrated that the CVB3-induced miR-21 triggers heart muscle cell damage by interfering with the cell-cell interactions. miR-21 suppresses the levels of components in cell-cell interactions by either promoting the degradation of those proteins or directly inhibiting the protein production. Inhibition of miR-21 can reduce the host injury caused by CVB3 infection. Our findings will shed new lights on the pathogenesis of CVB3-induced heart failure.

MicroRNA profiling of Sendai virus-infected A549 cells identifies miR-203 as an interferon-inducible regulator of IFIT1/ISG56

The mammalian type I interferon (IFN) response is a primary barrier for virus infection and is essential for complete innate and adaptive immunity. Both IFN production and IFN-mediated antiviral signaling are the result of differential cellular gene expression, a process that is tightly controlled at transcriptional and translational levels. To determine the potential for microRNA (miRNA)-mediated regulation of the antiviral response, small-RNA profiling was used to analyze the miRNA content of human A549 cells at steady state and following infection with the Cantell strain of Sendai virus, a potent inducer of IFN and cellular antiviral responses. While the miRNA content of the cells was largely unaltered by infection, specific changes in miRNA abundance were identified during Sendai virus infection. One miRNA, miR-203, was found to accumulate in infected cells and in response to IFN treatment. Results indicate that miR-203 is an IFN-inducible miRNA that can negatively regulate a number of cellular mRNAs, including an IFN-stimulated gene target, IFIT1/ISG56, by destabilizing its mRNA transcript.

Both PI3K- and mTOR-signaling pathways take part in CVB3-induced apoptosis of Hela cells

This work illustrated the mechanism contributing to the process of Phosphatidylinostiol 3-kinase (PI3K)/protein kinase B (PKB)/mammalian target of rapamycin (mTOR) signaling pathway, which has been demonstrated to play an important role in virus-induced apoptosis, which contributes to the Viral Myocarditis (VMC) pathogeneses. We examined the expression of Bax, Bim, caspase-3, caspase-9, and viral replication after Coxsackievirus B3 (CVB3) infection using the mTOR inhibitor and PI3K inhibitor pretreated HeLa cells, respectively. Apoptosis in different groups was determined by flow cytometry. Bax, Bim, caspase-9, and caspase-3 were examined by semiquantitative polymerase chain reaction (PCR) and Western blot analysis. The expression of CVB3 mRNA and viral capsid protein VP1 were analyzed by semiquantitative PCR and Western blot analysis distinctively. We found that rapamycin and LY294002 promote CVB3-induced cytopathic effect (CPE) and apoptosis. CVB3 replication in host cells is mediated in mRNA and protein expression by rapamycin and LY294002. Moreover, comparing with controls, at 12 and 24 h of postinfection (p.i.), Bim and Bax expression increased in cells after treated with rapamycin or LY294002, which also stimulates the activation of procaspase-9, and the CVB3-induced caspase-3 self-cleavage. However, in the meantime, the mRNA expression of caspase-9 and caspase-3 did not have an obvious change. In summary, our results demonstrated that the mTOR-signaling pathway plays an important role in CVB3-induced CPE and apoptosis, which is indispensable in VMC, via regulating Bim, Bax, caspase-9, caspase-3, and viral replication. Our findings may provide a new perspective and a deeper understanding of the mechanism of CVB3-induced apoptosis which, in turn, may help with the development of new therapy for the CVB3 infection.

Online resources for miRNA analysis

OBJECTIVE

This review aims to provide a brief introduction to each major category of available tools and algorithms for microRNA (miRNA) research, as well as to present some of the most widely used or promising representative applications.

METHODS

Only tools offering a fully functional web interface have been included, excluding implementations requiring deployment in local servers or workstations. Furthermore, we have specifically evaluated implementations focusing on Homo sapiens or on mammals used extensively in in vivo research, such as mice and rats.

RESULTS

We present an overview of databases and repositories of miRNA sequences and expression, a commentary on miRNA target prediction algorithms, tools for miRNA functional investigation, and online pipelines for the analysis of high throughput experiments. Examples and case studies are provided at the end of the manuscript, which can hopefully contribute in elucidating the utility of these implementations to basic and applied research.

CONCLUSIONS

Computational tools and algorithms play a significant role in miRNA-related research, supporting equally basic and applied research efforts. However, numerous challenges still remain to be answered by the relevant research community.

MicroRNAs, hepatitis C virus, and HCV/HIV-1 co-infection: new insights in pathogenesis and therapy

MicroRNAs (miRNAs) can exert a profound effect on Hepatitis C virus (HCV) replication. The interaction of HCV with the highly liver-enriched miRNA, miR-122 represents one such unique example of viruses having evolved mechanism(s) to usurp the host miRNA machinery to support viral life cycle. Furthermore, HCV infection can also trigger changes in the cellular miRNA profile, which may ultimately contribute to the outcome of viral infection. Accumulating knowledge on HCV-host miRNA interactions has ultimately influenced the design of therapeutic interventions against chronic HCV infection. The importance of microRNA modulation in Human Immunodeficiency Virus (HIV-1) replication has been reported, albeit only in the context of HIV-1 mono-infection. The development of HCV infection is dramatically influenced during co-infection with HIV-1. Here, we review the current knowledge on miRNAs in HCV mono-infection. In addition, we discuss the potential role of some miRNAs, identified from the analyses of public data, in HCV/HIV-1 co-infection.