MiR-146 and miR-125 in the regulation of innate immunity and inflammation

A Multimodal Therapeutic Strategy for Inflammatory Bowel Disease Using MicroRNA-146a Mimic Encapsulated in Lipid Nanoparticles

Dysregulated microRNAs (miRNAs) have significant potential as diagnostic tools for various chronic diseases; however, their therapeutic applications remain largely unexplored. Given their capacity to regulate multiple pathways, miRNAs are promising candidates for treating pleiotropic diseases, such as inflammatory bowel disease (IBD). In our study, we conducted a comprehensive review of the literature of miRNA-146 levels in the inflamed tissues of IBD patients and murine colitis models. Initially, we quantified the expression of miRNA-146a and miRNA-146b in the colons of mice using the dextran sodium sulfate (DSS)-inducedacute model of IBD. We selected miRNA-146a for further study due to its anti-inflammatory properties and potential relevance in IBD treatment. We hypothesized that a macrophage model of inflammation would be well-suited to studying the effects of this miRNA. Subsequently, we investigated the use of lipid nanoparticles (LNPs) for the targeted delivery of miRNA-146a to macrophages, which play a key role in IBD. Our results indicated that miRNA-146a levels increased in the DSS model and LNP-mediated delivery effectively downregulated genes associated with inflammation. These findings highlight the critical role of miRNA-146a in modulating IBD and suggest that LNP-based delivery could be a promising therapeutic strategy for managing inflammatory responses.

Preclinical and mechanistic perspectives on adipose-derived stem cells for atherosclerotic cardiovascular disease treatment

Adipose-derived mesenchymal stem cells (AD-MSCs) are a promising therapeutic modality for cardiovascular diseases due to their immunomodulatory, anti-inflammatory, and pro-angiogenic properties. This manuscript explores the current status, challenges, and future directions of AD-MSC therapies, focusing on their application in atherosclerosis (AS), myocardial infarction (MI), and heart failure (HF). Preclinical studies highlight AD-MSC's ability to stabilise atherosclerotic plaques, reduce inflammation, and enhance myocardial repair through mechanisms such as macrophage polarisation, endothelial protection, and angiogenesis. Genetically and pharmacologically modified AD-MSCs, including those overexpressing SIRT1, IGF-1, and PD-L1 or primed with bioactive compounds, exhibit superior efficacy compared to unmodified cells. These modifications enhance cell survival, immunopotency, and reparative capacity, showcasing the potential for tailored therapies. However, clinical translation faces significant hurdles. While recent clinical trials have confirmed the safety of AD-MSC therapy, their efficacy remains inconsistent, necessitating further optimisation of patient selection, dosing strategies, and delivery methods. Donor variability, particularly in patients with co-morbidities like type 2 diabetes (T2D) or obesity, impairs AD-MSC efficacy. Emerging research on extracellular vesicles (EVs) derived from AD-MSC offers a promising cell-free alternative, retaining the therapeutic benefits while mitigating risks. Future perspectives emphasise the need for multidisciplinary approaches to overcome these limitations. Strategies include refining genetic modifications, exploring EV-based therapies, and integrating personalised medicine and advanced diagnostic tools. By addressing these challenges, AD-MSC therapies hold the potential to revolutionise the treatment of cardiovascular diseases, providing innovative solutions to improve patient outcomes.

The novel miR_146-Tfdp2 axis antagonizes METH induced neuron apoptosis and cell cycle abnormalities in tree shrew

Methamphetamine (METH) is a synthetic drug with potent addictive, relapse, and neurotoxic properties. METH abuse contributes to severe damage to the central nervous system, potentially causing cognitive impairments, behavioral changes, and neurodegenerative diseases. METH-induced neuronal damage is closely related to apoptosis and cell cycle abnormalities, while gene expression regulator microRNAs (miRNAs) may play extensive roles in this progress, but the specific mechanisms remain unclear. We found that the novel miRNA 146 (miR_146) was downregulated in METH-induced apoptosis and cell cycle arrest in tree shrew primary neurons, while the expression of its target gene Tfdp2 was increased after METH exposure. Overexpression of miR_146 or silencing of Tfdp2 significantly alleviated METH-induced cell cycle arrest and apoptosis in primary tree shrew neurons. These findings provide new insights into the role of the miR_146-Tfdp2 axis in METH-induced neurotoxic injury and offer a theoretical basis for miR_146 as potential therapeutic targets in drug abuse.

Inflammation pathways as therapeutic targets in angiotensin II induced atrial fibrillation

Atrial fibrillation (AF), a common cardiac arrhythmia, is associated with severe complications such as stroke and heart failure. Although the precise mechanisms underlying AF remain elusive, inflammation is acknowledged as a pivotal factor in its progression. Angiotensin II (AngII) is implicated in promoting atrial remodeling and inflammation. However, the exact pathways through which AngII exacerbates AF are still not fully defined. This study explores the key molecular mechanisms involved, including dysregulation of calcium ions, altered connexin expression, and activation of signaling pathways such as TGF-β, PI3K/AKT, MAPK, NF-κB/NLRP3, and Rac1/JAK/STAT3. These pathways are instrumental in contributing to atrial fibrosis, electrical remodeling, and increased susceptibility to AF. Ang II-induced inflammation disrupts ion channel function, resulting in structural and electrical remodeling of the atria and significantly elevating the risk of AF. Anti-inflammatory treatments such as RAAS inhibitors, colchicine, and statins have demonstrated potential in reducing the incidence of AF, although clinical outcomes are inconsistent. This manuscript underscores the link between AngII-induced inflammation and the development of AF, proposing the importance of targeting inflammation in the management of AF.

Prenatal SARS-CoV-2 Infection Alters Human Milk-Derived Extracellular Vesicles

Human milk-derived extracellular vesicles (HMEVs) are key components in breast milk, promoting infant health and development. Maternal conditions could affect HMEV cargo; however, the impact of SARS-CoV-2 infection on HMEVs remains unknown. This study investigated the influence of SARS-CoV-2 infection during pregnancy on postpartum HMEV molecules. The median duration from SARS-CoV-2 test positivity to milk collection was 3 months. After defatting and casein micelle disaggregation, HMEVs were isolated from milk samples of nine mothers with prenatal SARS-CoV-2 and six controls by sequential centrifugation, ultrafiltration, and qEV-size exclusion chromatography. The presence of HMEV was confirmed via transmission electron microscopy. Nanoparticle tracking analysis demonstrated particle diameters of <200 nm and yields of >1 × 1011 particles per mL of milk. Western immunoblots detected ALIX, CD9, and HSP70, supporting the presence of HMEVs in the isolates. Cargo from thousands of HMEVs were analyzed using a multi-omics approach, including proteomics and microRNA sequencing, and predicted that mothers with prenatal SARS-CoV-2 infection produced HMEVs with enhanced functionalities involving metabolic reprogramming, mucosal tissue development, and immunomodulation. Our findings suggest that SARS-CoV-2 infection during pregnancy boosts mucosal site-specific functions of HMEVs, potentially protecting infants against viral infections. Further prospective studies should be pursued to reevaluate the short- and long-term benefits of breastfeeding in the post-COVID era.

DENV-1 Infection of Macrophages Induces Pyroptosis and Causes Changes in MicroRNA Expression Profiles

BACKGROUND

Dengue virus (DENV) is the most widespread mosquito-borne virus, which can cause dengue fever with mild symptoms, or progress to fatal dengue hemorrhagic fever and dengue shock syndrome. As the main target cells of DENV, macrophages are responsible for the innate immune response against the virus.

METHODS

In this study, we investigated the role of pyroptosis in the pathogenic mechanism of dengue fever by examining the level of pyroptosis in DENV-1-infected macrophages and further screened differentially expressed microRNAs by high-throughput sequencing to predict microRNAs that could affect the pyroptosis of the macrophage.

RESULTS

Macrophages infected with DENV-1 were induced with decreased cell viability, decreased release of lactate dehydrogenase and IL-1β, activation of NLRP3 inflammasome and caspase-1, cleavage of GSDMD to produce an N-terminal fragment bound to cell membrane, and finally induced macrophage pyroptosis. MicroRNA expression profiles were obtained by sequencing macrophages from all periods of DENV-1 infection and comparing with the negative control. Sixty-three microRNAs differentially expressed in both the early and later stages of infection were also identified. In particular, miR-223-3p, miR-148a-3p, miR-125a-5p, miR-146a-5p and miR-34a-5p were recognized as small molecules that may be involved in the regulation of inflammation.

CONCLUSIONS

In summary, this study aimed to understand the pathogenic mechanism of DENV through relevant molecular mechanisms and provide new targets for dengue-specific therapy.

MiR-146a-5p engineered hucMSC-derived extracellular vesicles attenuate Dermatophagoides farinae-induced allergic airway epithelial cell inflammation

INTRODUCTION

Allergic asthma is prevalent in children, with Dermatophagoides farinae as a common indoor allergen. Current treatments for allergic airway inflammation are limited and carry risks. Mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) show promise as a cell-free therapeutic approach. However, the use of engineered MSC-EVs for D. farinae-induced allergic airway epithelial cell inflammation remains unexplored.

METHODS

We generated miR-146a-5p-engineered EVs from human umbilical cord mesenchymal stem cells (hucMSCs) and established D. farinae-induced mouse and human bronchial epithelial cell allergic models. Levels of IL-1β, IL-18, IL-4, IL-5, IL-6, IL-10, IL-33, TNF-α and IgE were detected using ELISA. The relative TRAF6 and IRAK1 mRNA expression was quantified using qPCR assay and the NLRP3, NF-κB, IRAK1 and TRAF6 protein expression was determined using Western blotting. The regulatory effect of IRAK1 and TRAF6 by miR-146a-5p was examined using a dual luciferase reporter assay, and the nuclear translocation of NF-κB p65 into 16-HBE cells was evaluated using immunofluorescence assay.

RESULTS

Treatment with hucMSC-EVs effectively reduced allergic inflammation, while miR-146a-5p engineered hucMSC-EVs showed greater efficacy. The enhanced efficacy in alleviating allergic airway inflammation was attributed to the downregulation of IRAK1 and TRAF6 expression, facilitated by miR-146a-5p. This downregulation subsequently led to a decrease in NF-κB nuclear translocation, which in turn resulted in reduced activation of the NLRP3 inflammasome and diminished production of inflammatory cytokines, including IL-6, TNF-α, IL-1β and IL-18.

CONCLUSION

Our study underscores the potential of miR-146a-5p engineered hucMSC-EVs as a cell-free therapeutic strategy for D. farinae-induced allergic airway inflammation, offering a promising avenue for boosting anti-inflammatory responses.

MicroRNAs Regulate the Expression of Genes Related to the Innate Immune and Inflammatory Response in Rabbits Infected with Lagovirus europaeus GI.1 and GI.2 Genotypes

MicroRNAs (miR) are a group of small, non-coding RNAs of 17-25 nucleotides that regulate gene expression at the post-transcriptional level. Dysregulation of miRNA expression or function may contribute to abnormal gene expression and signaling pathways, leading to disease pathology. Lagovirus europaeus (L. europaeus) causes severe disease in rabbits called rabbit hemorrhagic disease (RHD). The symptoms of liver, lung, kidney, and spleen degeneration observed during RHD are similar to those of acute liver failure (ALF) and multi-organ failure (MOF) in humans. In this study, we assessed the expression of miRs and their target genes involved in the innate immune and inflammatory response. Also, we assessed their potential impact on pathways in L. europaeus infection-two genotypes (GI.1 and GI.2)-in the liver, lungs, kidneys, and spleen. The expression of miRs and target genes was determined using quantitative real-time PCR (qPCR). We assessed the expression of miR-155 (MyD88, TAB2, p65, NLRP3), miR-146a (IRAK1, TRAF6), miR-223 (TLR4, IKKα, NLRP3), and miR-125b (MyD88). We also examined biomarkers of inflammation: IL-1β, IL-6, TNF-α, and IL-18 in four tissues at the mRNA level. Our study shows that the main regulators of the innate immune and inflammatory response in L. europaeus/GI.1 and GI.2 infection, as well as RHD, are miR-155, miR-223, and miR-146a. During infection with L. europaeus/RHD, miR-155 has both pro- and anti-inflammatory effects in the liver and anti-inflammatory effects in the kidneys and spleen; miR-146a has anti-inflammatory effects in the liver, lungs and kidneys; miR-223 has anti-inflammatory effects in all tissues; however, miR-125b has anti-inflammatory effects only in the liver. In each case, such an effect may be a determinant of the pathogenesis of RHD. Our research shows that miRs may regulate three innate immune and inflammatory response pathways in L. europaeus infection. However, the result of this regulation may be influenced by the tissue microenvironment. Our research shows that infection of rabbits with L. europaeus/GI.1 and GI.2 genotypes causes an overexpression of two critical acute phase cytokines: IL-6 in all examined tissues and TNF-α (in the liver, lungs, and spleen). IL-1β was highly expressed only in the lungs after L. europaeus infection. These facts indicate a strong and rapid involvement of the local innate immune and inflammatory response in L. europaeus infection-two genotypes (GI.1 and GI.2)-and in the pathogenesis of RHD. Profile of biomarkers of inflammation in rabbits infected with L. europaeus/GI.1 and GI.2 genotypes are similar regarding the nature of changes but are different for individual tissues. Therefore, we propose three inflammation profiles for L. europaeus infection for both GI.1 and GI.2 genotypes (pulmonary, renal, liver, and spleen).

Lactobacillus rhamnosus and Lactobacillus delbrueckii Ameliorate the Expression of miR-125a and miR-146a in Systemic Lupus Erythematosus Patients

The microRNAs are non-coding RNA molecules involved in physiological and pathological processes, causing autoimmune diseases such as systemic lupus erythematosus (SLE). Probiotics are living microorganisms that possess beneficial effects on the host immune system and modulate it. The effect of Lactobacillus rhamnosus and Lactobacillus delbrueckii on the expression of miR-125a and miR-146a was studied in peripheral blood mononuclear cells (PBMCs) from newly diagnosed lupus patients in this in vitro study. During this study, 20 recently diagnosed SLE patients and 20 healthy individuals participated. Ficoll method was used to isolate the PBMCs from whole blood, which were cultured for 48 h with Lactobacillus rhamnosus and Lactobacillus delbrueckii. In the next step, total RNA containing microRNA was extracted. cDNA was synthesized for miR-125a and miR-146a genes and analyzed by real-time PCR. Results were presented as fold changes. As compared to healthy controls, SLE patients expressed lower levels of miR-125a and miR-146a. PBMCs treated with Lactobacillus rhamnosus, Lactobacillus delbrueckii, or both probiotics had significantly higher levels of miR-125a and miR-146a compared to the untreated group. Treatment of PBMCs with both L. rhamnosus and L. delbrueckii upregulated the expression of miR-125a and miR-146a in treated cells compared with untreated cells in SLE patients (p = 0.02, p = 0.001). Lactobacillus rhamnosus and Lactobacillus delbrueckii modify lupus patients' immune responses and disease effects by regulating miR-125a and miR-146a.

Spatiotemporal Dysregulation of Neuron-Glia Related Genes and Pro-/Anti-Inflammatory miRNAs in the 5xFAD Mouse Model of Alzheimer's Disease

Alzheimer's disease (AD), the leading cause of dementia, is a multifactorial disease influenced by aging, genetics, and environmental factors. miRNAs are crucial regulators of gene expression and play significant roles in AD onset and progression. This exploratory study analyzed the expression levels of 28 genes and 5 miRNAs (miR-124-3p, miR-125b-5p, miR-21-5p, miR-146a-5p, and miR-155-5p) related to AD pathology and neuroimmune responses using RT-qPCR. Analyses were conducted in the prefrontal cortex (PFC) and the hippocampus (HPC) of the 5xFAD mouse AD model at 6 and 9 months old. Data highlighted upregulated genes encoding for glial fibrillary acidic protein (Gfap), triggering receptor expressed on myeloid cells (Trem2) and cystatin F (Cst7), in the 5xFAD mice at both regions and ages highlighting their roles as critical disease players and potential biomarkers. Overexpression of genes encoding for CCAAT enhancer-binding protein alpha (Cebpa) and myelin proteolipid protein (Plp) in the PFC, as well as for BCL2 apoptosis regulator (Bcl2) and purinergic receptor P2Y12 (P2yr12) in the HPC, together with upregulated microRNA(miR)-146a-5p in the PFC, prevailed in 9-month-old animals. miR-155 positively correlated with miR-146a and miR-21 in the PFC, and miR-125b positively correlated with miR-155, miR-21, while miR-146a in the HPC. Correlations between genes and miRNAs were dynamic, varying by genotype, region, and age, suggesting an intricate, disease-modulated interaction between miRNAs and target pathways. These findings contribute to our understanding of miRNAs as therapeutic targets for AD, given their multifaceted effects on neurons and glial cells.

In-depth transcriptome profiling of Cherry Valley duck lungs exposed to chronic heat stress

Amidst rising global temperatures, chronic heat stress (CHS) is increasingly problematic for the poultry industry. While mammalian CHS responses are well-studied, avian-specific research is lacking. This study uses in-depth transcriptome sequencing to evaluate the pulmonary response of Cherry Valley ducks to CHS at ambient temperatures of 20°C and a heat-stressed 29°C. We detailed the CHS-induced gene expression changes, encompassing mRNAs, lncRNAs, and miRNAs. Through protein-protein interaction network analysis, we identified central genes involved in the heat stress response-TLR7, IGF1, MAP3K1, CIITA, LCP2, PRKCB, and PLCB2. Subsequent functional enrichment analysis of the differentially expressed genes and RNA targets revealed significant engagement in immune responses and regulatory processes. KEGG pathway analysis underscored crucial immune pathways, specifically those related to intestinal IgA production and Toll-like receptor signaling, as well as Salmonella infection and calcium signaling pathways. Importantly, we determined six miRNAs-miR-146, miR-217, miR-29a-3p, miR-10926, miR-146b-5p, and miR-17-1-3p-as potential key regulators within the ceRNA network. These findings enhance our comprehension of the physiological adaptation of ducks to CHS and may provide a foundation for developing strategies to improve duck production under thermal stress.

Deregulated miR-146a-3p alleviates disease progression in atherosclerosis through inactivating NF-κB: An experimental study

BACKGROUND

Atherosclerosis (AS), as a complex chronic inflammatory disease, is 1 of the main causes of cardiovascular and cerebrovascular diseases. This study aimed to confirm the direct interaction between miR-146a-3p and NF-κB, and explore the role of miR-146a-3p/NF-κB in the regulation of inflammation in AS.

METHODS

Bioinformatic prediction and dual-luciferase reporter assay were used to confirm the interaction between miR-146a-3p and NF-κB. Lipopolysaccharides stimulation was performed to establish AS inflammatory cell model, and the levels of pro-inflammatory cytokines were estimated using an enzyme-linked immunosorbent assay. miR-146a-3p and NF-κB expression were evaluated using reverse transcription quantitative PCR, and their clinical value was examined using a receiver operating characteristic curve.

RESULTS

Inflammatory cell model showed increased IL-1β, IL-6, and TNF-α. NF-κB was a target gene of miR-146a-3p, and mediated the inhibitory effects of miR-146a-3p on inflammatory responses in the cell model. In patients with AS, miR-146a-3p/NF-κB was associated with patients' clinical data and inflammatory cytokine levels, and aberrant miR-146a-3p and NF-κB showed diagnostic accuracy to distinguish AS patients from healthy populations.

CONCLUSION

miR-146a-3p might inhibit inflammation by targeting NF-κB in AS progression, and miR-146a-3p/ NF-κB might provide novel biomarkers and therapeutic targets for the prevention of AS and related vascular events.

miRNA-Mediated Fine Regulation of TLR-Induced M1 Polarization

Macrophage polarization to the M1 spectrum is induced by bacterial cell wall components through stimulation of Toll-like family (TLR) receptors. By orchestrating the expression of relevant mediators of the TLR cascade, as well as associated pathways and feedback loops, macrophage polarization is coordinated to ensure an appropriate immune response. This is central to the successful control of pathogens and the maintenance of health. Macrophage polarization is known to be modulated at both the transcriptional and post-transcriptional levels. In recent years, the miRNA-based post-transcriptional regulation of M1 polarization has received increasing attention from the scientific community. Comparative studies have shown that TLR stimulation alters the miRNA profile of macrophages and that macrophages from the M1 or the M2 spectrum differ in terms of miRNAs expressed. Simultaneously, miRNAs are considered critical post-transcriptional regulators of macrophage polarization. In particular, miRNAs are thought to play a regulatory role in the switch between the early proinflammatory response and the resolution phase. In this review, we will discuss the current state of knowledge on the complex interaction of transcriptional and post-transcriptional regulatory mechanisms that ultimately determine the functionality of macrophages.

The effect of chronic, non-pathogenic maternal immune activation on offspring postnatal muscle and immune outcomes

The objective was to determine the effects of maternal inflammation on offspring muscle development and postnatal innate immune response. Sixteen first-parity gilts were randomly allotted to repeated intravenous injections with lipopolysaccharide (LPS; n = 8, treatment code INFLAM) or comparable volume of phosphate buffered saline (CON, n = 8). Injections took place every other day from gestational day (GD) 70 to GD 84 with an initial dose of 10 μg LPS/kg body weight (BW) increasing by 12% each time to prevent endotoxin tolerance. On GD 70, 76, and 84, blood was collected at 0 and 4 h postinjection via jugular or ear venipuncture to determine tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β concentrations. After farrowing, litter mortality was recorded, and the pig closest to litter BW average was used for dissection and muscle fiber characterization. On weaning (postnatal day [PND] 21), pigs were weighed individually and 2 barrows closest to litter BW average were selected for another study. The third barrow closest to litter BW average was selected for the postnatal LPS challenge. On PND 52, pigs were given 5 μg LPS/kg BW via intraperitoneal injection, and blood was collected at 0, 4, and 8 h postinjection to determine TNF-α concentration. INFLAM gilt TNF-α concentration increased (P < 0.01) 4 h postinjection compared to 0 h postinjection, while CON gilt TNF-α concentration did not differ between time points. INFLAM gilt IL-6 and IL-1β concentrations increased (P = 0.03) 4 h postinjection compared to 0 h postinjection on GD 70, but did not differ between time points on GD 76 and 84. There were no differences between INFLAM and CON gilts litter mortality outcomes (P ≥ 0.13), but INFLAM pigs were smaller (P = 0.04) at birth and tended (P = 0.09) to be smaller at weaning. Muscle and organ weights did not differ (P ≥ 0.17) between treatments, with the exception of semitendinosus, which was smaller (P < 0.01) in INFLAM pigs. INFLAM pigs tended (P = 0.06) to have larger type I fibers. INFLAM pig TNF-α concentration did not differ across time, while CON pig TNF-α concentration peaked (P = 0.01) 4 h postinjection. TNF-α concentration did not differ between treatments at 0 and 8 h postinjection, but CON pigs had increased (P = 0.01) TNF-α compared to INFLAM pigs 4 h postinjection. Overall, maternal immune activation did not alter pig muscle development, but resulted in suppressed innate immune activation.

CIRCESPL1 SILENCING PROTECTS AGAINST LPS-INDUCED LUNG FIBROBLAST DYSFUNCTION PARTLY BY TARGETING THE MIR-146B-3P/TRAF1 AXIS IN PNEUMONIA

ABSTRACT

Background: Neonatal pneumonia is a common disease in the neonatal period with high mortality. The present work concentrated on the role and mechanism of circular RNA extra spindle pole bodies like 1, separase (circESPL1) in LPS-induced dysfunction of lung fibroblasts. Methods: Reverse transcription-quantitative polymerase chain reaction and Western blot assay were conducted to analyze RNA and protein expression, respectively. Cell viability, proliferation, apoptosis, and inflammation were assessed by Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine assay, flow cytometry, and enzyme-linked immunosorbent assay, respectively. Dual-luciferase reporter assay and RNA immunoprecipitation assay were conducted to verify the intermolecular interactions among circESPL1, miR-146b-3p, and TRAF1. Results: CircESPL1 expression was upregulated in the serum samples of pneumonia patients and LPS-induced lung fibroblasts. CircESPL1 silencing protected lung fibroblasts against LPS-induced dysfunction. CircESPL1 bound to microRNA-146b-3p (miR-146b-3p) in lung fibroblasts. CircESPL1 knockdown-mediated protective effects on LPS-induced lung fibroblasts were largely reversed by the silence of miR-146b-3p. miR-146b-3p directly interacted with the 3' untranslated region of TNF receptor associated factor 1 (TRAF1), and TRAF1 expression was regulated by the circESPL1/miR-146b-3p axis in lung fibroblasts. TRAF1 overexpression largely reversed miR-146b-3p accumulation-mediated protective effects on LPS-induced lung fibroblasts. Conclusion: CircESPL1 knockdown protected lung fibroblasts from LPS-induced injury partly by targeting the miR-146b-3p/TRAF1 axis.

Characteristics of conserved microRNAome and their evolutionary adaptation to regulation of immune defense functions in the spleen of silver carp and bighead carp

Immune defense functions of silver carp (Hypophthalmichthys molitrix) and bighead carp (Hypophthalmichthys nobilis) have shown obvious evolutionary divergence. MiRNAs participate in the fine regulation of immune function. However, the evolutionary adaptation of miRNAs in the regulation of immune defense function is still poorly understood in silver carp and bighead carp. Here, small RNA libraries were constructed from the spleen tissue of one-year-old and three-year-old healthy silver carp and bighead carp, 424 and 422 known conserved miRNAs were respectively identified from the spleen of silver carp and bighead carp by bioinformatic analysis, which 398 were shared between the two species. These conserved miRNAs showed highly similar expression patterns between silver carp and bighead carp, but the abundance in spleen varied greatly in different species. Family analysis showed that miRNA families including mir-8, mir-7, mir-23, mir-338, mir-30, mir-27, mir-221, mir-19, mir-181, mir-17, mir-15, mir-148, mir-130, mir-10 and let-7 were the main miRNAs in the spleen of silver carp and bighead carp. 27 and 51 significant differentially expressed (SDE) miRNAs were identified from silver carp and bighead carp, respectively. Evolution analysis for the predicted target genes of SDE-miRNAs showed that ten biological processes such as blood coagulation, cell adhesion mediated by integrin and adaptive immune response were positively selected. In addition, immune genes including TLR3, NFATC3, MALT1, B2M, GILT and MHCII were positively selected only in silver carp, and they were specifically targeted by the SDE-miRNAs including miR-9-5p, miR-196a-5p, miR-375, miR-122, miR-722, miR-132-3p, miR-727-5p, miR-724, miR-19d-5p and miR-138-5p, respectively. PLA2G4 in Fc epsilon RI signaling pathway was positively selected only in bighead carp and was specifically targeted by the SDE-miRNAs including miR-222b, miR-22b-5p, miR-15c, miR-146a, miR-125c-3p, miR-221-5p, miR-2188-5p, miR-142a-3p, miR-212, miR-138-5p and miR-15b-5p. In particular, SDE-miRNAs such as miR-144-3p, miR-2188-3p, miR-731, miR-363-3p and miR-218b could simultaneously target multiple evolutionarily differentiated immune-related genes. These results indicated that in the spleen of silver carp and bighead carp, conserved miRNAs have obvious evolutionary adaptations in the regulation of immune defense function. The results of this study can provide valuable resources for further revealing themechanism of miRNA in the formation of resistance traits evolution between silver carp and bighead carp.

Altered expression of miR-125a and dysregulated cytokines in systemic lupus erythematosus: Unveiling diagnostic and prognostic markers

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disorder impacting multiple organs, influenced by genetic factors, especially those related to the immune system. However, there is a need for new biomarkers in SLE. MicroRNA-125a (miR-125a) levels are decreased in T cells, B cells, and dendritic cells of SLE patients. MiR-125a plays a regulatory role in controlling the levels of tumor necrosis factor-alpha (TNF-α) and interleukin 12 (IL-12), which are crucial pro-inflammatory cytokines in SLE pathogenesis.

AIM

To assess the levels of miR-125a, IL-12, and TNF-α in SLE patients' plasma, evaluating their diagnostic and prognostic value.

METHODS

The study included 100 healthy individuals, 50 newly diagnosed (ND), and 50 SLE patients undergoing treatment. The patients were monitored for a duration of 24 wk to observe and record instances of relapses. MiR-125a expression was measured using real-time reverse transcription polymerase chain reaction, while ELISA kits were used to assess IL-12 and TNF-α production.

RESULTS

The results showed significantly reduced miR-125a expression in SLE patients compared to healthy individuals, with the lowest levels in ND patients. TNF-α and IL-12 expression levels were significantly elevated in SLE patients, especially in the early stages of the disease. Receiver operating characteristic curve analyses, and Cox-Mantel Log-rank tests indicated miR-125a, TNF-α, and IL-12 as proper diagnostic biomarkers for SLE. A negative correlation was found between plasma miR-125a expression and IL-12/TNF-α levels in SLE patients.

CONCLUSION

Decreased miR-125a levels may be involved in the development of SLE, while elevated levels of IL-12 and TNF-α contribute to immune dysregulation. These findings offer new diagnostic and prognostic markers for SLE. Moreover, the negative correlation observed suggests an interaction between miR-125a, TNF-α, and IL-12. Further research is necessary to uncover the underlying mechanisms that govern these relationships.

Luteolin Pretreatment Ameliorates Myocardial Ischemia/Reperfusion Injury by lncRNA-JPX/miR-146b Axis

Background

In the present study, we aimed to find out whether luteolin (Lut) pretreatment could ameliorate myocardial ischemia/reperfusion (I/R) injury by regulating the lncRNA just proximal to XIST (JPX)/microRNA-146b (miR-146b) axis.

Methods

We established the models in vitro (HL-1 cells) and in vivo (C57BL/6J mice) to certify the protection mechanism of Lut pretreatment on myocardial I/R injury. Dual luciferase reporter gene assay was utilized for validating that JPX could bind to miR-146b. JPX and miR-146b expression levels were determined by RT-qPCR. Western blot was utilized to examine apoptosis-related protein expression levels, including cleaved caspase-9, caspase-9, cleaved caspase-3, caspase-3, Bcl-2, Bax, and BAG-1. Apoptosis was analyzed by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, as well as flow cytometry. Animal echocardiography was used to measure cardiac function (ejection fraction (EF) and fractional shortening (FS) indicators).

Results

miR-146b was demonstrated to bind and recognize the JPX sequence site by dual luciferase reporter gene assay. The expression level of miR-146b was corroborated to be enhanced by H/R using RT-qPCR (P < 0.001 vs. Con). Moreover, JPX could reduce the expression of miR-146b, whereas inhibiting JPX could reverse the alteration (P < 0.001 vs. H/R, respectively). Western blot analysis demonstrated that Lut pretreatment increased BAG-1 expression level and Bcl-2/Bax ratio, but diminished the ratio of cleaved caspase 9/caspase 9 and cleaved caspase 3/caspase 3 (P < 0.001 vs. H/R, respectively). Moreover, the cell apoptosis change trend, measured by Annexin V-APC/7-AAD dualstaining, Hoechst 33342 staining, along with flow cytometry, was consistent with that of apoptosis-related proteins. Furthermore, pretreatment with Lut improved cardiac function (EF and FS) (P < 0.001 vs. I/R, respectively), as indicated in animal echocardiography.

Conclusion

Our results demonstrated that in vitro and in vivo, Lut pretreatment inhibited apoptosis via the JPX/miR-146b axis, ultimately improving myocardial I/R injury.

Integrated analysis of a miRNA-mRNA network related to immunity and autophagy in Macrobrachium rosenbergii infected with Aeromonas hydrophila

MicroRNAs (miRNAs) are a group of RNAs that regulate gene expression in the post-transcriptionally. miRNAs can regulate numerous processes, such as the immune response, due to their dynamic expression patterns. The giant freshwater prawn Macrobrachium rosenbergii is a major freshwater aquaculture prawn that is attacked by various bacteria, including Aeromonas hydrophila. For this study, we performed an analysis of the miRNA and mRNA transcriptome analysis of M. rosenbergii which was infected with A. hydrophila. We identified 56 differentially expressed miRNAs (DEMs) and 1542 differentially expressed mRNAs. Furthermore, an integrated analysis of miRNA-mRNA expression led to the identification of 729 differentially predicted target genes (DETGs) of the DEMs. Multiple functional categories related to immunity, apoptosis, and autophagy were found to be enriched in the DETGs. During the infection of M. rosenbergii by A. hydrophila, an elaborate regulatory network involving Toll and immune deficiency (IMD) signaling, mitogen-activated protein kinase (MAPK) signaling, lysosome, and cell apoptosis was formed by a complex interplay of 40 crucial DEMs and 22 DETGs, all associated with the immune and autophagy pathway. The findings suggest that infection with A. hydrophila triggers intricate responses in both miRNA and mRNA, significantly impacting immune and autophagy processes in M. rosenbergii.

Modulation of miR-146b Expression during Aging and the Impact of Physical Activity on Its Expression and Chondrogenic Progenitors

The finding of molecules associated with aging is important for the prevention of chronic degenerative diseases and for longevity strategies. MicroRNAs (miRNAs) are post-transcriptional regulators involved in many biological processes and miR-146b-5p has been shown to be involved in different degenerative diseases. However, miR-146b-5p modulation has not been evaluated in mesenchymal stem cells (MSCs) commitment or during aging. Therefore, the modulation of miR-146b-5p in the commitment and differentiation of mesenchymal cells as well as during maturation and aging in zebrafish model were analyzed. In addition, circulating miR-146b-5p was evaluated in human subjects at different age ranges. Thus, the role of physical activity in the modulation of miR-146b-5p was also investigated. To achieve these aims, RT (real-time)-PCR, Western blot, cell transfections, and three-dimensional (3D) culture techniques were applied. Our findings show that miR-146b-5p expression drives MSCs to adipogenic differentiation and increases during zebrafish maturation and aging. In addition, miR-146b-5p expression is higher in females compared to males and it is associated with the aging in humans. Interestingly, we also observed that the physical activity of walking downregulates circulating miR-146b-5p levels in human females and increases the number of chondroprogenitors. In conclusion, miR-146b-5p can be considered an age-related marker and can represent a useful marker for identifying strategies, such as physical activity, aimed at counteracting the degenerative processes of aging.

Mesenchymal stem cell-derived exosomes: a possible therapeutic strategy for repairing heart injuries

Mesenchymal stem cells (MSCs) are one of the most potent therapeutic strategies for repairing cardiac injury. It has been shown in the latest studies that MSCs cannot survive in the heart for a long time. Consequently, the exosomes secreted by MSCs may dominate the repair of heart injury and promote the restoration of cardiac cells, vascular proliferation, immune regulation, etc. Based on the current research, the progress of the acting mechanism, application prospects and challenges of exosomes, including non-coding RNA, in repairing cardiac injuries are summarised in this article.

Circulating Small RNA Profiling of Patients with Alveolar and Cystic Echinococcosis

Alveolar (AE) and cystic (CE) echinococcosis are two parasitic diseases caused by the tapeworms Echinococcus multilocularis and E. granulosus sensu lato (s. l.), respectively. Currently, AE and CE are mainly diagnosed by means of imaging techniques, serology, and clinical and epidemiological data. However, no viability markers that indicate parasite state during infection are available. Extracellular small RNAs (sRNAs) are short non-coding RNAs that can be secreted by cells through association with extracellular vesicles, proteins, or lipoproteins. Circulating sRNAs can show altered expression in pathological states; hence, they are intensively studied as biomarkers for several diseases. Here, we profiled the sRNA transcriptomes of AE and CE patients to identify novel biomarkers to aid in medical decisions when current diagnostic procedures are inconclusive. For this, endogenous and parasitic sRNAs were analyzed by sRNA sequencing in serum from disease negative, positive, and treated patients and patients harboring a non-parasitic lesion. Consequently, 20 differentially expressed sRNAs associated with AE, CE, and/or non-parasitic lesion were identified. Our results represent an in-depth characterization of the effect E. multilocularis and E. granulosus s. l. exert on the extracellular sRNA landscape in human infections and provide a set of novel candidate biomarkers for both AE and CE detection.

RNA-seq reveals the role of miR-223 in alleviating inflammation of bovine mammary epithelial cells

Bovine mammary epithelial cells (bMECs) are involved in the early defense against the invasion of intramammary pathogens and are essential for the health of bovine mammary gland. MicroRNA (MiRNA) is a key factor that regulates cell state and physiological function. In the present study, the transcriptome profiles of miR-223 inhibitor transfection group (miR-223_Inhibitor) and negative control inhibitor transfection group (NC_Inhibitor) within bMECs were detected via the RNA sequencing (RNA-seq) platform. Based on these experiments, the differentially expressed mRNAs (DE-mRNAs) of the miR-223_Inhibitor transfection group were screened, and the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes functional analyses of DE-mRNAs were performed. The results revealed that compared with the NC_Inhibitor, 224 differentially expressed genes (DEGs) were identified in the miR-223_Inhibitor, including 184 upregulated and 40 downregulated genes. The functional annotation of the above DEGs indicated that some of these genes are involved in the immune response generated by extracellular substance stimulation, regulation of the activity of cytokines and chemokines, and the immune signaling pathways of NF-κB and TNF. Meanwhile, miR-223_inhibitor upregulated the immune key genes IRF1 and NFκBIA, cytokines IL-6 and IL-24, as well as chemokines CXCL3, CXCL5, and CCR6, triggering a signaling cascade response that exacerbated inflammation in bMECs. These results suggested that miR-223 plays an important role in inhibiting the inflammatory response and maintaining the stability of bMECs, and is a potential target for treating mastitis in dairy cows.

An updated review on cell signaling pathways regulated by candidate miRNAs in coronary artery disease

MicroRNAs (miRNAs) are small endogenous non-coding RNA, size range from 17 to 25 nucleotides that regulate gene expression at the post-transcriptional level. More than 2000 different types of miRNAs have been identified in humans which regulate about 60% of gene expression, since the discovery of the first miRNA in 1993. MicroRNA performs many functions such as being involved in the regulation of various biological pathways for example cell migration, cell proliferation, cell differentiation, disease progression, and initiation. miRNAs also play an important role in the development of atherosclerosis lesions, cardiac fibroblast, cardiac hypertrophy, cancer, and neurological disorders. Abnormal activation of many cell signaling pathways has been observed in the development of coronary artery disease. Abnormal expression of these candidate miRNA genes leads to up or downregulation of specific genes, these specific genes play an important role in the regulation of cell signaling pathways involved in coronary artery disease. Many studies have found that miRNAs play a key role in the regulation of crucial signaling pathways that are involved in the pathophysiology of coronary artery disease. This review is designed to investigate the role of cell signaling pathways regulated by candidate miRNAs in Coronary artery disease.

Chronic Inflammation as an Underlying Mechanism of Ageing and Ageing-Related Diseases

Age-related chronic inflammation is characterized as the unresolved low-grade inflammatory process underlying the ageing process and various age-related diseases. In this chapter, we review the age-related changes in the oxidative stress-sensitive pro-inflammatory NF-κB signaling pathways causally linked with chronic inflammation during ageing based on senoinflammation schema. We describe various age-related dysregulated pro- and anti-inflammatory cytokines, chemokines, and senescence-associated secretory phenotype (SASP), and alterations of inflammasome, specialized pro-resolving lipid mediators (SPM), and autophagy as major players in the chronic inflammatory intracellular signaling network. A better understanding of the molecular, cellular, and systemic mechanisms involved in chronic inflammation in the ageing process would provide further insights into the potential anti-inflammatory strategies.

Genome-wide identification of antisense lncRNAs and their association with susceptibility to Flavobacterium psychrophilum in rainbow trout

Eukaryotic genomes encode long noncoding natural antisense transcripts (lncNATs) that have been increasingly recognized as regulatory members of gene expression. Recently, we identified a few antisense transcripts correlating in expression with immune-related genes. However, a systematic genome-wide analysis of lncNATs in rainbow trout is lacking. This study used 134 RNA-Seq datasets from five different projects to identify antisense transcripts. A total of 13,503 lncNATs were identified genome-wide. About 75% of lncNATs showed multiple exons compared to 36.5% of the intergenic lncRNAs. RNA-Seq datasets from resistant, control, and susceptible rainbow trout genetic lines with significant differences in survival rate following Flavobacterium psychrophilum (Fp) infection were analyzed to investigate the potential role of the lncNATs during infection. Twenty-four pairwise comparisons between the different genetic lines, infectious status, and time points revealed 581 differentially expressed (DE) lncNATs and 179 differentially used exons (DUEs). Most of the DE lncNATs strongly and positively correlated in expression with their corresponding sense transcripts across 24 RNA-Seq datasets. LncNATs complementary to genes related to immunity, muscle contraction, proteolysis, and iron/heme metabolism were DE following infection. LncNATs complementary to hemolysis-related genes were DE in the resistant fish compared to susceptible fish on day 5 post-infection, suggesting enhanced clearance of free hemoglobin (Hb) and heme and increased erythropoiesis. LncNATs complementary to hepcidin, a master negative regulator of the plasma iron concentration, were the most downregulated lncNATs on day 5 of bacterial infection in the resistant fish. Ninety-four DE lncNAT, including five complementary to hepcidin, are located within 26 QTL regions previously identified in association with bacterial cold water disease (BCWD) in rainbow trout. Collectively, lncNATs are involved in the molecular architecture of fish immunity and should be further investigated for potential applications in genomic selection and genetic manipulation in aquaculture.

The Roles of MiRNAs (MicroRNAs) in Melanoma Immunotherapy

Melanoma is the most aggressive form of skin cancer, characterized by life-threatening and rapidly spreading progression. Traditional targeted therapy can alleviate tumors by inactivating hyperactive kinases such as BRAF or MEK but inevitably encounters drug resistance. The advent of immunotherapy has revolutionized melanoma treatment and significantly improved the prognosis of melanoma patients. MicroRNAs (miRNAs) are intricately involved in innate and adaptive immunity and are implicated in melanoma immunotherapy. This systematic review describes the roles of miRNAs in regulating the functions of immune cells in skin and melanoma, as well as the involvement of miRNAs in pharmacology including the effect, resistance and immune-related adverse events of checkpoint inhibitors such as PD-1 and CTLA-4 inhibitors, which are used for treating cutaneous, uveal and mucosal melanoma. The expressions and functions of miRNAs in immunotherapy employing tumor-infiltrating lymphocytes and Toll-like receptor 9 agonists are also discussed. The prospect of innovative therapeutic strategies such as the combined administration of miRNAs and immune checkpoint inhibitors and the nanotechnology-based delivery of miRNAs are also provided. A comprehensive understanding of the interplay between miRNAs and immunotherapy is crucial for the discovery of reliable biomarkers and for the development of novel miRNA-based therapeutics against melanoma.

Updated review of advances in microRNAs and complex diseases: experimental results, databases, webservers and data fusion

MicroRNAs (miRNAs) are gene regulators involved in the pathogenesis of complex diseases such as cancers, and thus serve as potential diagnostic markers and therapeutic targets. The prerequisite for designing effective miRNA therapies is accurate discovery of miRNA-disease associations (MDAs), which has attracted substantial research interests during the last 15 years, as reflected by more than 55 000 related entries available on PubMed. Abundant experimental data gathered from the wealth of literature could effectively support the development of computational models for predicting novel associations. In 2017, Chen et al. published the first-ever comprehensive review on MDA prediction, presenting various relevant databases, 20 representative computational models, and suggestions for building more powerful ones. In the current review, as the continuation of the previous study, we revisit miRNA biogenesis, detection techniques and functions; summarize recent experimental findings related to common miRNA-associated diseases; introduce recent updates of miRNA-relevant databases and novel database releases since 2017, present mainstream webservers and new webserver releases since 2017 and finally elaborate on how fusion of diverse data sources has contributed to accurate MDA prediction.

An enriched environment reduces hippocampal inflammatory response and improves cognitive function in a mouse model of stroke

An enriched environment is used as a behavioral intervention therapy that applies sensory, motor, and social stimulation, and has been used in basic and clinical research of various neurological diseases. In this study, we established mouse models of photothrombotic stroke and, 24 hours later, raised them in a standard, enriched, or isolated environment for 4 weeks. Compared with the mice raised in a standard environment, the cognitive function of mice raised in an enriched environment was better and the pathological damage in the hippocampal CA1 region was remarkably alleviated. Furthermore, protein expression levels of tumor necrosis factor receptor-associated factor 6, nuclear factor κB p65, interleukin-6, and tumor necrosis factor α, and the mRNA expression level of tumor necrosis factor receptor-associated factor 6 were greatly lower, while the expression level of miR-146a-5p was higher. Compared with the mice raised in a standard environment, changes in these indices in mice raised in an isolated environment were opposite to mice raised in an enriched environment. These findings suggest that different living environments affect the hippocampal inflammatory response and cognitive function in a mouse model of stroke. An enriched environment can improve cognitive function following stroke through up-regulation of miR-146a-5p expression and a reduction in the inflammatory response.

MicroRNA-146: Biomarker and Mediator of Cardiovascular Disease

Cardiovascular diseases (CVDs) are the prime cause of morbidity and mortality worldwide. Although noticeable progress has been made in the diagnosis, prognosis, and treatment, there is still a critical demand for new diagnostic biomarkers and novel therapeutic interventions to reduce this disease incidence. Many investigations have been conducted on the regulatory effects of microRNAs in cardiovascular diseases. miRNA circulating serum level changes are correlated with several CVDs. In addition, there is growing evidence representing the potential role of miRNAs as diagnostic biomarkers or potential therapeutic targets for CVD. Preliminary studies identified the prominent role of miR-146 in host defense, innate immunity, and different immunological diseases by regulating cytokine production and innate immunity modification in bacterial infections. However, more recently, it was also associated with CVD development. miR-146 has received much attention, with positive results in most studies. Research demonstrated the crucial role of this molecule in the pathogenesis of cardiac disease and related mechanisms. As a result, many potential applications of miR-146 are expected. In this paper, we provide an overview of recent studies highlighting the role of miR-146 in CVD, focusing on CAD (coronary artery disease), cardiomyopathy, and MI (myocardial infarction) in particular and discussing its current scientific state, and use a prognostic biomarker as a therapeutic agent for cardiovascular diseases.

The monocyte-to-osteoclast transition in rheumatoid arthritis: Recent findings

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation leading to joint destruction and deformity. The crucial role of osteoclasts in the bone erosion in RA has been demonstrated. Deregulated osteoclastogenesis which is affected by environmental factors including the inflammatory state, as well as genetic and epigenetic factors, is one of hallmarks of RA pathogenesis. An enhanced-monocyte-to-osteoclast transition plays an important role in osteoclast upregulation in RA because under specific stimuli, circulating monocytes might migrate to a specific location in the bones and fuse with each other to become mature multinucleated osteoclasts. To understand the mechanism of bone damage in RA and to develop novel treatments targeting osteoclast upregulation, it is important to clarify our understanding of the monocyte-to-osteoclast transition in RA. Several potential targets which inhibit both inflammation and osteoclastogenesis, as well as regulators that affect the monocyte-to-osteoclast transition have been revealed by recent studies. Here, we review the factors affecting osteoclastogenesis in RA, summarize the anti-osteoclastogenic effects of current RA treatments, and identify promising therapeutic targets relating to both inflammation and osteoclastogenesis.

Urinary microRNAome in healthy cats and cats with pyelonephritis or other urological conditions

MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression at the post-transcriptional level. miRNAs have been found in urine and have shown diagnostic potential in human nephropathies. Here, we aimed to characterize, for the first time, the feline urinary miRNAome and explore the use of urinary miRNA profiles as non-invasive biomarkers for feline pyelonephritis (PN). Thirty-eight cats were included in a prospective case-control study and classified in five groups: healthy Control cats (n = 11), cats with PN (n = 10), cats with subclinical bacteriuria or cystitis (SB/C, n = 5), cats with ureteral obstruction (n = 7) and cats with chronic kidney disease (n = 5). By small RNA sequencing we identified 212 miRNAs in cat urine, including annotated (n = 137) and putative novel (n = 75) miRNAs. The 15 most highly abundant urinary miRNAs accounted for nearly 71% of all detected miRNAs, most of which were previously identified in feline kidney. Ninety-nine differentially abundant (DA) miRNAs were identified when comparing Control cats to cats with urological conditions and 102 DA miRNAs when comparing PN to other urological conditions. Tissue clustering analysis revealed that the majority of urine samples clustered close to kidney, which confirm the likely cellular origin of the secreted urinary miRNAs. Relevant DA miRNAs were verified by quantitative real-time PCR (qPCR). Eighteen miRNAs discriminated Control cats from cats with a urological condition. Of those, seven miRNAs were DA by both RNAseq and qPCR methods between Control and PN cats (miR-125b-5p, miR-27a-3p, miR-21-5p, miR-27b-3p, miR-125a-5p, miR-17-5p and miR-23a-3p) or DA between Control and SB/C cats (miR-125b-5p). Six additional miRNAs (miR-30b-5p, miR-30c, miR-30e-5p, miR-27a-3p, miR-27b-39 and miR-222) relevant for discriminating PN from other urological conditions were identified by qPCR alone (n = 4) or by both methods (n = 2) (P<0.05). This panel of 13 miRNAs has potential as non-invasive urinary biomarkers for diagnostic of PN and other urological conditions in cats.

The Core Human MicroRNAs Regulated by Toxoplasma gondii

BACKGROUND

Toxoplasma gondii (T. gondii) is an intracellular zoonotic protozoan parasite known to effectively modulate the host system for its survival. A large number of microRNAs (miRNAs) regulated by different strains of T. gondii in diverse types of host cells/tissues/organs have been reported across multiple studies.

OBJECTIVE

We aimed to decipher the complexity of T. gondii regulated spectrum of miRNAs to derive a set of core miRNAs central to different strains of T. gondii infection in diverse human cell lines.

METHODS

We first assembled miRNAs hat are regulated by T. gondii altered across the various assortment of infections and time points of T. gondii infection in multiple cell types. For these assembled datasets, we employed specific criteria to filter the core miRNAs regulated by T. gondii. Subsequently, accounting for the spectrum of miRNA-mRNA target combinations, we applied a novel confidence criterion to extract their core experimentally-validated mRNA targets in human cell systems.

RESULTS

This analysis resulted in the extraction of 74 core differentially regulated miRNAs and their 319 high-confidence mRNA targets. Based on these core miRNA-mRNA pairs, we derived the central biological processes perturbed by T. gondii in diverse human cell systems. Further, our analysis also resulted in the identification of novel autocrine/paracrine signalling factors that could be associated with host response modulated by T. gondii.

CONCLUSION

The current analysis derived a set of core miRNAs, their targets, and associated biological processes fine-tuned by T. gondii for its survival within the invaded cells.

Enhanced Cognition and Neurogenesis in miR-146b Deficient Mice

The miR-146 family consists of two microRNAs (miRNAs), miR-146a and miR-146b, which are both known to suppress a variety of immune responses. Here in this study, we show that miR-146b is abundantly expressed in neuronal cells, while miR-146a is mainly expressed in microglia and astroglia of adult mice. Accordingly, miR-146b deficient (Mir146b-/-) mice exhibited anxiety-like behaviors and enhanced cognition. Characterization of cellular composition of Mir146b-/- mice using flow cytometry revealed an increased number of neurons and a decreased abundancy of astroglia in the hippocampus and frontal cortex, whereas microglia abundancy remained unchanged. Immunohistochemistry showed a higher density of neurons in the frontal cortex of Mir146b-/- mice, enhanced hippocampal neurogenesis as evidenced by an increased proliferation, and survival of newly generated cells with enhanced maturation into neuronal phenotype. No microglial activation or signs of neuroinflammation were observed in Mir146b-/- mice. Further analysis demonstrated that miR-146b deficiency is associated with elevated expression of glial cell line-derived neurotrophic factor (Gdnf) mRNA in the hippocampus, which might be at least in part responsible for the observed neuronal expansion and the behavioral phenotype. This hypothesis is partially supported by the positive correlation between performance of mice in the object recognition test and Gdnf mRNA expression in Mir146b-/- mice. Together, these results show the distinct function of miR-146b in controlling behaviors and provide new insights in understanding cell-specific function of miR-146b in the neuronal and astroglial organization of the mouse brain.

MicroRNA‑146a attenuates isoproterenol‑induced cardiac fibrosis by inhibiting FGF2

Cardiac fibrosis is a key factor of heart failure. Increasing evidence suggests that microRNAs (miRNAs/miRs) serve vital roles in the pathogenesis of cardiac fibrosis. The present study aimed to investigate the role of miR-146a-5p in isoproterenol (ISO)-induced cardiac fibrosis. Reverse transcription-quantitative PCR analysis demonstrated that miR-146a-5p expression was downregulated in ISO-treated rat heart tissue and ISO-induced cardiac fibroblasts (CFs). Conversely, the expression levels of basic fibroblast growth factor 2 (FGF2), collagen I and smooth muscle α-actin (α-SMA) were upregulated in ISO-treated rat cardiac tissue and CFs. Furthermore, viability and differentiation were inhibited in ISO-induced CFs transfected with miR-146a-5p mimics. Dual-luciferase reporter assay confirmed that miR-146a-5p targeted FGF2. Notably, FGF2 expression was suppressed following overexpression of miR-146a-5p, while FGF2 expression increased following miR-146a-5p knockdown. In addition, FGF2 knockdown suppressed the expression levels of FGF2, collagen I and α-SMA levels in CFs. Taken together, the results of the present study suggested that the miR-146a-5p/FGF2 pathway may be a novel therapy for cardiac fibrosis.

Circulating microRNA profiling is altered in the acute respiratory distress syndrome related to SARS-CoV-2 infection

One of the hallmarks of SARS-CoV-2 infection is an induced immune dysregulation, in some cases resulting in cytokine storm syndrome and acute respiratory distress syndrome (ARDS). Several physiological parameters are altered as a result of infection and cytokine storm. Among them, microRNAs (miRNAs) might reflect this poor condition since they play a significant role in immune cellular performance including inflammatory responses. Circulating miRNAs in patients who underwent ARDS and needed mechanical ventilation (MV+; n = 15) were analyzed by next generation sequencing in comparison with patients who had COVID-19 poor symptoms but without intensive care unit requirement (MV−; n = 13). A comprehensive in silico analysis by integration with public gene expression dataset and pathway enrichment was performed. Whole miRNA sequencing identified 170 differentially expressed miRNAs between patient groups. After the validation step by qPCR in an independent sample set (MV+  = 10 vs. MV− = 10), the miR-369-3p was found significantly decreased in MV+ patients (Fold change − 2.7). After integrating with gene expression results from COVID-19 patients, the most significant GO enriched pathways were acute inflammatory response, regulation of transmembrane receptor protein Ser/Thr, fat cell differentiation, and regulation of biomineralization and ossification. In conclusion, miR-369-3p was altered in patients with mechanical ventilation requirement in comparison with COVID-19 patients without this requirement. This miRNA is involved in inflammatory response which it can be considered as a prognosis factor for ARDS in COVID-19 patients.

Expression characteristics and interaction networks of microRNAs in spleen tissues of grass carp (Ctenopharyngodon idella)

The spleen is an important immune organ in fish. MicroRNAs (miRNAs) have been shown to play an important role in the regulation of immune function. However, miRNA expression profiles and their interaction networks associated with the postnatal late development of spleen tissue are still poorly understood in fish. The grass carp (Ctenopharyngodon idella) is an important economic aquaculture species in China. Here, two small RNA libraries were constructed from the spleen tissue of healthy grass carp at one-year-old and three-year-old. A total of 324 known conserved miRNAs and 9 novel miRNAs were identified by using bioinformatic analysis. Family analysis showed that 23 families such as let-7, mir-1, mir-10, mir-124, mir-8, mir-7, mir-9, and mir-153 were highly conserved between vertebrates and invertebrates. In addition, 14 families such as mir-459, mir-430, mir-462, mir-7147, mir-2187, and mir-722 were present only in fish. Expression analysis showed that the expression patterns of miRNAs in the spleen of one-year-old and three-year-old grass carp were highly consistent, and the percentage of miRNAs with TPM > 100 was above 39%. Twenty significant differentially expressed (SDE) miRNAs were identified. Gene ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis showed that these SDE miRNAs were primarily involved in erythrocyte differentiation, lymphoid organ development, immune response, lipid metabolic process, the B cell receptor signaling pathway, the T cell receptor signaling pathway, and the PPAR signaling pathway. In addition, the following miRNA-mRNA interaction networks were constructed: immune and hematopoietic, cell proliferation and differentiation, and lipid metabolism. This study determined the miRNA transcriptome as well as miRNA-mRNA interaction networks in normal spleen tissue during the late development stages of grass carp. The results expand the number of known miRNAs in grass carp and are a valuable resource for better understanding the molecular biology of the spleen development in grass carp.

Micro RNAs as potential biomarkers in tuberculosis: A systematic review

Tuberculosis (TB) remains a major infectious disease across the globe. With increasing TB infections and a rise in multi-drug resistance, rapid diagnostic modalities are required to achieve TB control. Radiological investigations and microbiological tests (microscopic examination, cartridge-based nucleic acid amplification tests, and cultures) are most commonly used to diagnose TB. Histopathological/cytopathological examinations are also required for an accurate diagnosis in many patients. The causative agent, Mycobacterium tuberculosis (Mtb), is known to circumvent the host's immune system. Circulating microRNAs (miRNAs) play a crucial role in biological pathways and can be used as a potential biomarker to detect tuberculosis. miRNAs are small non-coding RNAs and negatively regulate gene expression during post-transcriptional regulation. The differential expression of miRNAs in multiple clinical samples in tuberculosis patients may be helpful as potential disease biomarkers. This review summarizes the literature on miRNAs in various clinical samples as biomarkers for TB diagnosis.

ER Stress is Involved in Mast Cells Degranulation via IRE1α/miR-125/Lyn Pathway in an Experimental Intracerebral Hemorrhage Mouse Model

The degranulation of mast cells accounts for the development of neuroinflammation following intracerebral hemorrhage (ICH). Inhibition of IRE1α, a sensor signaling protein related to endoplasmic reticulum stress, has been shown to exert anti-inflammatory effects in several neurological diseases. The objective of this study was to investigate the effects of IRE1α inhibition on mast cells degranulation in an ICH mouse model and to explore the contribution of miR-125/Lyn pathway in IRE1α-mediated mast cells degranulation. Male mice were subjected to ICH by intraparenchymal injection of autologous blood. STF083010, an inhibitor of IRE1α, was administered intranasally at 1 h after ICH induction. AntimiR-125 was delivered by intracerebroventricular (i.c.v.) injection prior to ICH induction to elucidate the possible mechanisms. Western blot analysis, immunofluorescence staining, neurological test, hematoma volume, brain water content, toluidine blue staining and reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) were performed. Endogenous phosphorylated IRE1α (p-IRE1α), tryptase, interleukin-17A (IL-17A), tumor necrosis factor α (TNF-α) and tryptase mRNA were increased in time dependent manner while miR-125b-2-3p was decreased after ICH. Inhibition of IRE1α, with STF083010, remarkably reduced brain water content, improved neurological function, decreased hematoma volume, upregulated the expression of miR-125b-2-3p, decreased the number of mast cells, and downregulated the protein expression of Lyn kinase, XBP1s (spliced X-box binding protein-1), tryptase, IL-17A and TNF-α. The downregulation of Lyn kinase, tryptase, IL-17A, TNF-α, and decreased mast cells number were reversed by antimiR-125. The present findings demonstrate that IRE1α inhibition attenuates mast cells degranulation and neuroinflammation, at least partially, through IRE1α/miR-125/Lyn signaling pathway after ICH.

An Apple a Day Keeps the Doctor Away: Potential Role of miRNA 146 on Macrophages Treated with Exosomes Derived from Apples

The constant dialogue between the plant world and the animal world (including man among them) has been known since the time of Adam and Eve, where an apple was the origin of the evils of the world. Apart from Snow White—who might have something to object to when it comes to the use of apples—fruits, plants, and natural extracts have been known for millennia as remedies for human health-related ailments. In the light of such evidence, the aim of the present work was to investigate from a biological point of view the potential role of apple exosomes in inflammatory processes on human cells. To this end we isolated and characterized apple exosomes and treated human cells such as macrophages and NCTC L929 as cancer cells in order to evaluate the tumorigenic and anti-inflammatory effect of apple exomes. Microscopic and molecular biology analyses were conducted to characterize exosomes and to assess cell proliferation, death, and miRNA line, as well as gene expression and the uptake of exosomes by cells. The results confirm the absolute biological safety of exosomes and their anti-inflammatory effect, mediated mainly by miRNA146 production by M2 macrophages.

Triple jeopardy in ageing: COVID-19, co-morbidities and inflamm-ageing

Covid-19 endangers lives, has disrupted normal life, changed the way medicine is practised and is likely to alter our world for the foreseeable future. Almost two years on since the presumptive first diagnosis of COVID-19 in China, more than two hundred and fifty million cases have been confirmed and more than five million people have died globally, with the figures rising daily. One of the most striking aspects of COVID-19 illness is the marked difference in individuals' experiences of the disease. Some, most often younger groups, are asymptomatic, whereas others become severely ill with acute respiratory distress syndrome (ARDS), pneumonia or proceed to fatal organ disease. The highest death rates are in the older and oldest age groups and in people with co-morbidities such as diabetes, heart disease and obesity. Three major questions seem important to consider. What do we understand about changes in the immune system that might contribute to the older person's risk of developing severe COVID-19? What factors contribute to the higher morbidity and mortality in older people with COVID-19? How could immunocompetence in the older and the frailest individuals and populations be supported and enhanced to give protection from serious COVID-19 illness?

Trichoderma stromaticum spores induce autophagy and downregulate inflammatory mediators in human peripheral blood-derived macrophages

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T. stromaticum biocontrol agent induces autophagy, up-regulating autophagy-related genes

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T. stromaticum modulates expression of micro RNAs that control imune response

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T. stromaticum dow-nregulates expression of TLR2, TLR4, CLEC7A, NLRP3, IL-10, IL1β and IL18

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T. stromaticum modulates ROS production

Trichoderma spp. are usually considered safe and normally used as biocontrol and biofertilization. Safety for human health is evaluated by several tests that detect various effects such as allergenicity, toxicity, infectivity, and pathogenicity. However, they do not evaluate the effects of the agent upon the immune system. The aim of this study was to investigate the interaction between T. stromaticum spores and mammalian cells to assess the immunomodulatory potential of the spores of this fungus. First, mouse macrophage cell line J774 and human macrophages were exposed to fungal spores and analyzed for structural features, through scanning and transmission electron microscopy. Then, various analysis were performed in human macrophages as to their effect in some functional and molecular aspects of the immune system through immunocytochemistry, flow cytometry and gene expression assays. We demonstrated that T. stromaticum spores induces autophagy and autophagy-related genes (ATGs) and downmodulate inflammatory mediators, including ROS, NLRP3, the cytokines IL-1β, IL-18, IL-12 and IL-10, as well as TLR2, TLR4, miR-146b and miR-155, which may lead to an augmented susceptibility to pathogens. Our study shows the extension of damages the biofungicide Tricovab® can cause in the innate immune response. Further studies are necessary to elucidate other innate and adaptive immune responses and, consequently, the safety of this fungus when in contact with humans.

MicroRNA‐146a and microRNA‐146b deficiency correlates with exacerbated disease activity, and their longitude increment relates to etanercept response in psoriasis patients

Background

MicroRNA (miR)‐146a and miR‐146b regulate autoimmunity, inflammation, and keratinocytes proliferation to engage in psoriasis pathology. The current study aimed to investigate their correlation with disease risk and clinical features, and the linkage of their longitudinal changes with clinical response to etanercept in psoriasis patients.

Methods

Plasma samples were collected from 84 moderate‐to‐severe psoriasis patients who underwent etanercept treatment (at baseline (M0), 1 month (M1), 3 months (M3), and 6 months (M6)), 80 disease controls and 80 health controls (both after enrollment); afterward, miR‐146a and miR‐146b expressions were detected by RT‐qPCR. Furthermore, PASI75 and PASI90 responses were assessed in psoriasis patients.

Results

Both miR‐146a and miR‐146b were decreased in psoriasis patients compared with disease controls and health controls (all p < 0.001), which also distinguished psoriasis patients from disease controls and health controls by receiver‐operating characteristic analyses. Furthermore, miR‐146a positively correlated with miR‐146b in psoriasis patients (p < 0.001) and disease controls (p = 0.005) but not in healthy controls (p = 0.062). In psoriasis patients, miR‐146a negatively related to psoriatic body surface area (p = 0.011) and PASI score (p = 0.003); miR‐146b negatively linked with PASI score (p = 0.020). At M1, M3, and M6 after etanercept treatment, PASI75 response rate was 14.3%, 32.1%, and 69.0%, respectively; PASI90 response rate was 1.2%, 17.9%, and 36.9%, respectively. During etanercept treatment, both miR‐146a and miR‐146b elevated gradually over time and their longitude increments were associated with PASI75 response (all p < 0.001).

Conclusion

MiR‐146a and miR‐146b might serve as indicators for optimizing etanercept application and improving treatment outcomes in psoriasis patients.

MicroRNAs as Potential Orchestrators of Alzheimer's Disease-Related Pathologies: Insights on Current Status and Future Possibilities

Alzheimer's disease (AD) is a progressive and deleterious neurodegenerative disease, strongly affecting the cognitive functions and memory of seniors worldwide. Around 58% of the affected patients live in low and middle-income countries, with estimates of increasing deaths caused by AD in the coming decade. AD is a multifactor pathology. Mitochondrial function declines in AD brain and is currently emerging as a hallmark of this disease. It has been considered as one of the intracellular processes severely compromised in AD. Many mitochondrial parameters decline already during aging; mitochondrial efficiency for energy production, reactive oxygen species (ROS) metabolism and the de novo synthesis of pyrimidines, to reach an extensive functional failure, concomitant with the onset of neurodegenerative conditions. Besides its impact on cognitive functions, AD is characterized by loss of synapses, extracellular amyloid plaques composed of the amyloid-β peptide (Aβ), and intracellular aggregates of hyperphosphorylated Tau protein, accompanied by drastic sleep disorders, sensory function alterations and pain sensitization. Unfortunately, till date, effective management of AD-related disorders and early, non-invasive AD diagnostic markers are yet to be found. MicroRNAs (miRNAs) are small non-coding nucleic acids that regulate key signaling pathway(s) in various disease conditions. About 70% of experimentally detectable miRNAs are expressed in the brain where they regulate neurite outgrowth, dendritic spine morphology, and synaptic plasticity. Increasing studies suggest that miRNAs are intimately involved in synaptic function and specific signals during memory formation. This has been the pivotal key for considering miRNAs crucial molecules to be studied in AD. MicroRNAs dysfunctions are increasingly acknowledged as a pivotal contributor in AD via deregulating genes involved in AD pathogenesis. Moreover, miRNAs have been proved to control pain sensitization processes and regulate circadian clock system that affects the sleep process. Interestingly, the differential expression of miRNA panels implies their emerging potential as diagnostic AD biomarkers. In this review, we will present an updated analysis of miRNAs role in regulating signaling processes that are involved in AD-related pathologies. We will discuss the current challenges against wider use of miRNAs and the future promising capabilities of miRNAs as diagnostic and therapeutic means for better management of AD.

Clinical significance of serum miR-101-3p expression in patients with neonatal sepsis

Aim: This study aimed to evaluate the levels and functions of miR-101-3p in neonatal sepsis (NS). Materials & methods: Quantitative real-time PCR was conducted to investigate the expression of miR-101-3p and the receiver operating characteristic curve was applied to manifest its diagnostic effects. Results: miR-101-3p was increased in the NS patients and the dysregulation of miR-101-3p was associated with levels of procalcitonin, CRP, IL-8 and TNF-α. The combination of miR-101-3p and procalcitonin could function as a promising indicator in distinguishing NS patients. The silenced miR-101-3p reversed the increased levels of TNF-α and IL-8 caused by lipopolysaccharide in vitro. DUSP1 was identified as a direct target gene of miR-101-3p in NS. Conclusion: The abundance of miR-101-3p facilitated the inflammation in NS by targeting DUSP1.

Non-coding RNAs in melanoma: Biological functions and potential clinical applications

Malignant melanoma (MM) is a malignant tumor that originates from melanocytes and has a high mortality rate. Therefore, early diagnosis and treatment are very important for survival. So far, the exact molecular mechanism leading to the occurrence of melanoma, especially the molecular metastatic mechanism, remains largely unknown. Non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNA (circRNAs), have been investigated and found to play vital roles in regulating tumor occurrence and development, including melanoma. In this review, we summarize the progress of recent research on the effects of ncRNAs on melanoma and attempt to elucidate the role of ncRNAs as molecular markers or potential targets that will provide promising application perspectives on melanoma.