Peripheral blood microRNAs expression is associated with infant respiratory syncytial virus infection

The Effects of Viruses on Insulin Sensitivity and Blood-Brain Barrier Function

In this review manuscript, we discuss the effects of select common viruses on insulin sensitivity and blood-brain barrier (BBB) function and the potential overlapping and distinct mechanisms involved in these effects. More specifically, we discuss the effects of human immunodeficiency virus (HIV), herpes, hepatitis, influenza, respiratory syncytial virus (RSV), and SARS-CoV-2 viruses on insulin sensitivity and BBB function and the proposed underlying mechanisms. These viruses differ in their ability to be transported across the BBB, disrupt the BBB, and/or alter the function of the BBB. For RSV and SARS-CoV-2, diabetes increases the risk of infection with the virus, in addition to viral infection increasing the risk for development of diabetes. For HIV and hepatitis C and E, enhanced TNF-a levels play a role in the detrimental effects. The winter of 2022-2023 has been labeled as a tridemic as influenza, RSV, and COVID-19 are all of concern during this flu season. There is an ongoing discussion about whether combined viral exposures of influenza, RSV, and COVID-19 have additive, synergistic, or interference effects. Therefore, increased efforts are warranted to determine how combined viral exposures affect insulin sensitivity and BBB function.

Noncoding RNAs and Virus and Treatment in Allergic Rhinitis

Allergic rhinitis (AR) is a type I hypersensitivity reaction disease caused by inhaled allergens and immunoglobulin E (IgE)-mediated. Noncoding RNA (ncRNA) is an important regulator involved in gene expression and can be detected in the cytoplasm or extracellular fluid, which mainly includes microRNAs (miRNA, length 22-24 nucleotides), long noncoding RNAs (lncRNA, length >200 nucleotides), and circRNAs. LncRNA and miRNA both participate in the regulation of immune function. Some respiratory viral infections can aggravate allergic rhinitis, such as a respiratory syncytial virus (RSV) and human metapneumovirus (hMPV). However, the interaction between viral infection and allergy is complex and the mechanism is still unclear. In this review, we summarized the interactions of noncoding RNAs and viruses in the occurrence and development of AR, along with the treatments focusing on the noncoding RNAs in the past five years.

Micro-Players of Great Significance-Host microRNA Signature in Viral Infections in Humans and Animals

Over time, more and more is becoming known about micro-players of great significance. This is particularly the case for microRNAs (miRNAs; miR), which have been found to participate in the regulation of many physiological and pathological processes in both humans and animals. One such process is viral infection in humans and animals, in which the host miRNAs—alone or in conjunction with the virus—interact on two levels: viruses may regulate the host’s miRNAs to evade its immune system, while the host miRNAs can play anti- or pro-viral roles. The purpose of this comprehensive review is to present the key miRNAs involved in viral infections in humans and animals. We summarize the data in the available literature, indicating that the signature miRNAs in human viral infections mainly include 12 miRNAs (i.e., miR-155, miR-223, miR-146a, miR-122, miR-125b, miR-132, miR-34a, miR -21, miR-16, miR-181 family, let-7 family, and miR-10a), while 10 miRNAs are commonly found in animals (i.e., miR-155, miR-223, miR-146a, miR-145, miR-21, miR-15a/miR-16 cluster, miR-181 family, let-7 family, and miR-122) in this context. Knowledge of which miRNAs are involved in different viral infections and the biological functions that they play can help in understanding the pathogenesis of viral diseases, facilitating the future development of therapeutic agents for both humans and animals.

Respiratory Syncytial Virus Nonstructural Protein 1 Promotes 5-Lipoxygenase via miR-19a-3p

Background

Respiratory syncytial virus (RSV) infection can regulate the expression of a wide range of noncoding microRNAs (miRNAs), in which mir-19a-3p can participate in airway inflammatory response by regulating 5-lipoxygenase (5-LO) pathway. RSV nonstructural protein (NS) 1 is involved in the airway hyperresponsiveness during RSV infection.

Methods

The expression levels of miR-19a-3p and inflammatory signaling-related indicators were detected using quantitative real-time PCR and western blot analyses on the A549 cells transfected with NS1 expression plasmids (pNS1). The 5-LO-mediated inflammatory signaling pathway was assessed when the miR-19a-3p or 5-LO was inhibited.

Results

The immunofluorescence analysis showed that the plasmid-mediated NS1 protein was observed in both the cytoplasm and nucleus. The expression level of miR-19a-3p was significantly upregulated in the pNS1 or RSV-treated cells, which was reversed by the NS1 small interfering RNA. In addition, pNS1 also upregulated the expression of 5-LO, interleukin-5 (IL-5), and leukotriene B4 (LTB4), which was also significantly inhibited by the miR-19a-3p antagonists. The 5-LO inhibitor MK886 prevented the increase in the expression level of IL-5 induced by pNS1.

Conclusions

These results suggested that the RSV NS1 might play an important role in the pathogenesis of RSV by activating the 5-LO and subsequent inflammatory cytokines through miR-19a-3p.

MiR-146a alleviates lung injury caused by RSV infection in young rats by targeting TRAF-6 and regulating JNK/ERKMAPK signaling pathways

Respiratory syncytial virus (RSV) is a major cause of acute lower respiratory tract infection in infants and children. The present study aimed to investigate the effects of miR-146a on RSV replication and the related mechanisms. Material and methods: We pretreated A549 and HEp-2 cells and young rats with miR-146a mimic before infection with RSV. The expressions of miR-146a and RSV-F mRNA in cells and lung tissues were detected by RT-qPCR, and production of IL-1β, IL-6, IL-18, and TNF-α in bronchial alveolar lavage fluid (BALF) were determined by ELISA. The expression level of TRAF-6 and activation of the JNK/ERK/MAPK/NF-κB signaling pathway was detected by Western blotting. Results: RSV infection significantly reduced miR-146a levels in both A549 and HEp-2 cells and rat lung tissues. RSV infection resulted in accelerated growth, increased release of inflammatory cytokines, increased expression of TRAF-6, and activation of the JNK pathway in cells, and the lung inflammatory infiltration and the pathological score increased in rats. Overexpression of miR-146a targeted down-regulation of TRAF-6 expression and JNK/ERK/MAPK/NF-κB pathway induced by RSV infection, reduced the production of inflammatory cytokines IL-1β, IL-6 and TNF-α, and alleviate lung injury in young rats. We got similar results in both A549 and HEp-2 cell experiments. Conclusion: MiR-146a alleviates lung injury caused by RSV infection in young rats by targeting TRAF-6 and regulating JNK/ERK/MAPK signaling pathways.

Epigenetic regulation of pediatric and neonatal immune responses

Epigenetic regulation of transcription is a collective term that refers to mechanisms known to regulate gene transcription without changing the underlying DNA sequence. These mechanisms include DNA methylation and histone tail modifications which influence chromatin accessibility, and microRNAs that act through post-transcriptional gene silencing. Epigenetics is known to regulate a variety of biological processes, and the role of epigtenetics in immunity and immune-mediated diseases is becoming increasingly recognized. While DNA methylation is the most widely studied, each of these systems play an important role in the development and maintenance of appropriate immune responses. There is clear evidence that epigenetic mechanisms contribute to developmental stage-specific immune responses in a cell-specific manner. There is also mounting evidence that prenatal exposures alter epigenetic profiles and subsequent immune function in exposed offspring. Early life exposures that are associated with poor long-term health outcomes also appear to impact immune specific epigenetic patterning. Finally, each of these epigenetic mechanisms contribute to the pathogenesis of a wide variety of diseases that manifest during childhood. This review will discuss each of these areas in detail. IMPACT: Epigenetics, including DNA methylation, histone tail modifications, and microRNA expression, dictate immune cell phenotypes. Epigenetics influence immune development and subsequent immune health. Prenatal, perinatal, and postnatal exposures alter immune cell epigenetic profiles and subsequent immune function. Numerous pediatric-onset diseases have an epigenetic component. Several successful strategies for childhood diseases target epigenetic mechanisms.

Small Non-coding RNA Expression Following Respiratory Syncytial Virus or Measles Virus Infection of Neuronal Cells

Respiratory syncytial virus (RSV) or measles virus (MeV) infection modifies host responses through small non-coding RNA (sncRNA) expression. We show that RSV or MeV infection of neuronal cells induces sncRNAs including various microRNAs and transfer RNA fragments (tRFs). We show that these tRFs originate from select tRNAs (GCC and CAC for glycine, CTT and AAC for Valine, and CCC and TTT for Lysine). Some of the tRNAs are rarely used by RSV or MeV as indicated by relative synonymous codon usage indices suggesting selective cleavage of the tRNAs occurs in infected neuronal cells. The data implies that differentially expressed sncRNAs may regulate host gene expression via multiple mechanisms in neuronal cells.

Circulating Exosomal MicroRNA Profiles Associated with Acute Soft Tissue Injury

Objective

This study aimed to characterize the circulating exosomal microRNA (miRNA) profiles associated with acute soft tissue injury.

Materials and Methods

In this experimental study, a total of 12 rats were randomly divided into control group and model group (n=6 for each group). The rats in the model group were used to establish an acute soft tissue injury following the mechanical injury of the leg. The exosomes from the peripheral blood of all the rats were isolated and then characterized by Nanosight NS300 particle size analyser (NTA), transmission electron microscopy (TEM) and western blot. Next, the exosomal miRNAs in the control and model groups were sequenced, and the differentially expressed miRNAs (DE-miRNAs) were identified using the DESeq algorithm. Functional analyses were performed using Gene Ontology (GO) terms and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway databases. Finally, quantitative reverse-transcription polymersa chain reaction (qRT-PCR) was used to verify the expression of the DE-miRNAs.

Results

TEM, NTA and western blot results showed that the exosomes were approximately 100 nm in size and exhibited cup-shaped morphology. A total of 628 miRNAs were obtained by sequencing. After that, 28 DE miRNAs (DEmiRNAs) were identified, including seven down-regulated miRNAs and 21 up-regulated miRNAs. These DE-miRNAs were linked to 7539 target genes with GO. Also, KEGG analyses demonstrated that these genes were enriched for phosphorylation, VEGF signaling pathway, and MAPK signaling pathway. Additionally, the consistency rate between the qRT-PCR and sequencing results was 83.33%, which showed a high relative reliability of the sequencing results.

Conclusion

These findings suggest that these 28 exosomal miRNAs may be involved in the regulation of acute soft tissue injury, by one of critical biological processes (BP), phosphorylation. The findings provide valuable clues by utilizing exosomes as therapeutic targets for the effective treatment of acute soft tissue injury.

MicroRNA-877-5p alleviates ARDS via enhancing PI3K/Akt path by targeting CDKN1B both in vivo and in vitro

Acute respiratory distress syndrome (ARDS) is a public health problem with high morbidity and mortality worldwide due to lacking known characteristic biomarkers and timely intervention. Pulmonary edema caused by inflammation and pulmonary microvascular endothelial cell disfunction is the main pathophysiological change of ARDS. Circulating microRNAs (miRNAs) are differentially expressed between subjects who did and did not develop ARDS. Many miRNAs have been exemplified to be involved in ARDS and could represent the novel therapeutic targets, but the role of microRNA-877-5p (miR-877-5p) in ARDS and its regulatory mechanisms are still unknown. Herein, we explore the underlying function of miR-877-5p toward anesis of ARDS and addressed that miRNA-877 can reduce the release of tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6 thus attenuating the damage of pulmonary microvascular endothelial cells (HPMECs). Have further evaluated the protein expression, we detected that miR-877-5p contributed to the relief of ARDS by suppressing Cyclin-dependent kinase inhibitor 1B (CDKN1B), which serves as a regulator of endothelial cell polarization and migration through phosphatidylinositol-3-kinase and AKT (PI3K/Akt) signaling pathway. Besides, we noticed that CDKN1B restrains cell differentiation by inhibiting Cdk2 (cyclin-dependent kinase 2), instead of Cdk4 (cyclin-dependent kinase 4), during which the nuclear translocation of CDKN1B may participate. Together, our works testified that miR-877-5p might suppress inflammatory responses and promote HPMECs regeneration via targeting CDKN1B by modulation of Cdk2 and PI3K/Akt path. These molecules likely modulating ARDS progression may inform biomarkers and therapeutic development.

Decreased miRNA-320e correlates with allergy in children with otitis media with effusion

OBJECTIVE

Otitis media with effusion (OME) is a common childhood disease and the main cause of conductive hearing loss in this age group. Many factors predispose to OME but allergy is still widely disputed. The answer may lay in the molecular mechanisms of ear exudate formation and the recent studies showed miRNAs might take part in it. MiRNAs are also potent regulators of allergic response. As miRNAs are present in the middle ear, we hypothesized their expression differs between allergic and non-allergic patients and reflects the difference in pathomechanism of effusion formation between these two groups.

MATERIALS AND METHODS

This study aimed to establish the expression of 5 different miRNAs (miR-223-3p, miR-451a, miR-16-5p, miR-320e, miR-25-3p) in ear exudates in children diagnosed with OME. The allergy group consisted of 18 patients whereas the non-allergic group had 36 patients. MicroRNA was isolated from the middle ear fluid collected during myringotomy and transcribed into cDNA. MiRNA expression was measured with TaqMan™ MicroRNA Assays and analyzed with DataAssist software. The comparative CT method was used for calculating the relative quantification of gene expression based on the endogenous control gene expression (U6 snRNA-001973).

RESULTS

MiR-320e expression was significantly decreased in allergic children with OME. Other studied miRNAs also showed reduced expression in allergic children, but the decrease was not significant.

CONCLUSIONS

MiRNA expression differs between children with and without allergy in the course of OME, but further studies are needed to explain the exact role of miR-320e and its target genes in OME pathology in allergic patients.

The Importance of miRNA Identification During Respiratory Viral Infections

The expression of small non-coding RNA MicroRNAs (miRNAs) during respiratory viral infections is of critical importance as they are implicated in the viral replication, immune responses and severity of disease pathogenesis. Respiratory viral infections have an extensive impact on human health across the globe. For that is essential to understand the factors that regulate the host response against infections. The differential miRNA pattern induced by respiratory viruses has been reported, including include influenza A virus (IAV), human respiratory syncytial virus (HRSV), human metapneumovirus (HMPV), adenovirus (AdV), and more recently, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. In this commentary, we highlight the importance of miRNAs identification and the contribution of these molecules in the modulation of the immune response through the upregulation and downregulation of miRNAs expression in different immune and non-immune cells.

miRNAs and Leukotrienes in Respiratory Syncytial Virus Infection

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate posttranscription by binding to 3'-untranslated regions of target mRNAs. Recent functional studies have elucidated mechanisms that miRNAs regulate leukotriene synthesis by perturbing arachidonic acid metabolism. Both microarrays and high-throughput sequencing revealed distinct differential expression of miRNAs in children with respiratory syncytial virus (RSV) infection compared with healthy controls. Abnormal miRNA expression may contribute to higher leukotriene levels, which is associated with airway hyperreactivity. Targeting miRNAs may benefit to restore the homeostasis of inflammatory reaction and provide new strategies to alleviate airway hyperreactivity induced by RSV. In this article, we provide an overview of the current knowledge about miRNAs modulating leukotrienes through regulation of arachidonic acid metabolism with a special focus on miRNAs aberrantly expressed in children with RSV infection.

Identification of miRNA-mRNA Crosstalk in Respiratory Syncytial Virus- (RSV-) Associated Pediatric Pneumonia through Integrated miRNAome and Transcriptome Analysis

Respiratory syncytial virus (RSV) is the most common respiratory virus and is associated with pediatric pneumonia, causing bronchiolitis and significant mortality in infants and young children. MicroRNAs (miRNAs) are endogenous noncoding small RNAs that function in gene regulation and are associated with host immune response and disease progression. In the present study, we profiled the global transcriptome and miRNAome of whole blood samples from children with mild or severe RSV-associated pneumonia, aiming to identify the potential biomarkers and investigate the molecular mechanisms of severe RSV-associated pediatric pneumonia. We found that expression profiles of whole blood microRNAs and mRNAs were altered and distinctly different in children with severe RSV-associated pneumonia. In particular, the four most significantly upregulated miRNAs in children with severe RSV-associated pneumonia were hsa-miR-1271-5p, hsa-miR-10a-3p, hsa-miR-125b-5p, and hsa-miR-30b-3p. The severe RSV-associated pneumonia-specific differentially expressed miRNA target interaction network was also contrasted. These target genes were further analyzed with Gene Ontology enrichment analysis. We found that most of the target genes were involved in inflammatory and immune responses, including the NF-κB signaling pathway, the MAPK signaling pathway, and T cell receptor signaling. Our findings will contribute to the identification of biomarkers and new drug design strategies to treat severe RSV-associated pediatric pneumonia.

Non-Coding RNAs and Their Role in Respiratory Syncytial Virus (RSV) and Human Metapneumovirus (hMPV) Infections

Recent high-throughput sequencing revealed that only 2% of the transcribed human genome codes for proteins, while the majority of transcriptional products are non-coding RNAs (ncRNAs). Herein, we review the current knowledge regarding ncRNAs, both host- and virus-derived, and their role in respiratory syncytial virus (RSV) and human metapneumovirus (hMPV) infections. RSV is known as the most common cause of lower respiratory tract infection (LRTI) in children, while hMPV is also a significant contributor to LRTI in the pediatrics population. Although RSV and hMPV are close members, belonging to the Pneumoviridae family, they induce distinct changes in the ncRNA profile. Several types of host ncRNAs, including long ncRNA (lncRNA), microRNAs (miRNAs), and transfer RNA (tRNA)-derived RNA fragments (tRFs), are involved as playing roles in RSV and/or hMPV infection. Given the importance of ncRNAs in regulating the expression and functions of genes and proteins, comprehensively understanding the roles of ncRNAs in RSV/hMPV infection could shed light upon the disease mechanisms of RSV and hMPV, potentially providing insights into the development of prevention strategies and antiviral therapy. The presence of viral-derived RNAs and the potential of using ncRNAs as diagnostic biomarkers are also discussed in this review.

Downregulation of serum exosomal miR-320d predicts poor prognosis in hepatocellular carcinoma

BACKGROUND

MicroRNAs (miRNAs) is a class of functional regulator of tumorigenesis of human cancer including hepatocellular carcinoma (HCC). However, the potential clinical significance of serum exosomal miR-320d in HCC has not been elucidated.

METHODS

Real-time reverse transcription PCR was used to detect the expression pattern of serum exosomal miR-320d in patients with HCC, and the correlation between the deregulation of serum exosomal miR-320d and the clinical outcome of HCC was explored. The biological function of exosomal miR-320d in HCC was also investigated.

RESULTS

Our results showed that the expression levels of exosomal miR-320d were remarkably reduced in the serum samples of HCC patients and the culture medium of HCC cell lines compared with their respective controls. Serum exosomal miR-320d could differentiate the HCC patients from healthy controls with high accuracy. In addition, its level was remarkably increased in the HCC patients who had received surgical treatment. Moreover, reduced serum exosomal miR-320d was associated with advanced tumor stage, positive lymph node metastasis, and poorly differentiated tumors. HCC patients with lower serum exosomal miR-320d had shorter overall and disease-free survival. Low serum exosomal miR-320d was identified to be an independent unfavorable prognostic factor for HCC. Finally, overexpression of miR-320d inhibited the proliferation and invasion of HCC cells, and BMI1 was demonstrated to be a direct target of miR-320d.

CONCLUSION

Taken together, serum exosomal miR-320d could be a potential non-invasive biomarker for the diagnosis and prognosis of HCC.

MicroRNAs in Asthma and Respiratory Infections: Identifying Common Pathways

MicroRNAs (miRs) are single-stranded RNAs of 18-25 nucleotides. These molecules regulate gene expression at the post-transcriptional level; several of these are differentially expressed in asthma as well as in viral acute respiratory infections (ARIs), the main triggers of acute asthma exacerbations. In recent years, miRs have been studied in order to discover drug targets as well as biomarkers for diagnosis, disease severity and prognosis. We describe recent findings on miR expression and function in asthma and their role in the regulation of viral ARIs, according to cell tissue specificity and asthma severity. By combining the above information, we identify miRs that may be important in virus-induced asthma exacerbations. This is the first attempt to link miR profiles of asthmatic patients and ARI-induced miRs, addressing the question of whether there might be a specific miR deficit in asthmatic subjects that make them more susceptible and/or reactive to infection.

Determining Immune and miRNA Biomarkers Related to Respiratory Syncytial Virus (RSV) Vaccine Types

Respiratory Syncytial Virus (RSV) causes serious respiratory tract illness and substantial morbidity and some mortality in populations at the extremes of age, i.e., infants, young children, and the elderly. To date, RSV vaccine development has been unsuccessful, a feature linked to the lack of biomarkers available to assess the safety and efficacy of RSV vaccine candidates. We examined microRNAs (miR) as potential biomarkers for different types of RSV vaccine candidates. In this study, mice were vaccinated with a live attenuated RSV candidate that lacks the small hydrophobic (SH) and attachment (G) proteins (CP52), an RSV G protein microparticle (GA2-MP) vaccine, a formalin-inactivated RSV (FI-RSV) vaccine or were mock-treated. Several immunological endpoints and miR expression profiles were determined in mouse serum and bronchoalveolar lavage (BAL) following vaccine priming, boost, and RSV challenge. We identified miRs that were linked with immunological parameters of disease and protection. We show that miRs are potential biomarkers providing valuable insights for vaccine development.

MicroRNAs: Mediators and Therapeutic Targets to Airway Hyper Reactivity After Respiratory Syncytial Virus Infection

Respiratory syncytial virus (RSV) is the most important pathogen correlated to the first-time infant wheezing and later recurrence after its primary infection. RSV infection promotes the bronchial smooth muscle sensitivity to leukotrienes (LTs) in acute stage, causes the extensive inflammatory reaction and the aggregation of Th2-like cells during respiratory tract obstruction. Infants and young children infected with RSV exhibit an increased susceptibility to the exposure of exogenous allergens, easy to suffer from the recurrent wheezing, which prompts that the body is still in a state of inflammation or immunological bias. However, the pathological mechanism is unclear. The recent researches demonstrate that abnormal expression of non-coding microRNAs (miRNAs) can be detected from the peripheral blood and airway tract epithelial of RSV infected infants, which participate the regulation of immune cells polarization and LTs synthesis. Improving the immune tolerance can significantly relieve the airway inflammation and broncho-spasm caused by RSV. In this review, we discuss recent advances in understanding the mechanism of RSV-induced inflammatory reaction and immune dysfunction leading to airway hyper-reactivity. Further, we summarize the potential molecular basis that, in this process, miRNAs, which are produced by airway epithelial cells or peripheral blood mononuclear cells, directly or in the form of exosome to regulate the inflammation programs as well as the function, differentiation and proliferation of immune cells. miRNAs may become a potential bio-marker of detecting severe RSV infection and a novel target of early intervention and therapeutic strategy in recurrent wheezing or asthma related to RSV infection.