MicroRNA-29 in the adaptive immune system: setting the threshold

MicroRNAs and human viral diseases: A focus on the role of microRNA-29

The viral replication can impress through cellular miRNAs. Indeed, either the antiviral responses or the viral infection changes through cellular miRNAs resulting in affecting many regulatory signaling pathways. One of the microRNA families that is effective in human cancers, diseases, and viral infections is the miR-29 family. Members of miR-29 family are effective in different viral infections as their roles have appeared in regulation of immunity pathways either in innate immunity including interferon and inflammatory pathways or in adaptive immunity including activation of T-cells and antibodies production. Although miR-29a affects viral replication by suppressing antiviral responses, it can inhibit the expression of viral mRNAs via binding to their 3'UTR. In the present work, we discuss the evidence related to miR-29a and viral infection through host immunity regulation. We also review roles of other miR-29 family members by focusing on their role as biomarkers for diagnosing and targets for viral diseases management.

MiR-29b inhibits COC expansion and oocyte in vitro maturation via induction of ROS by targeting CYCS

Cumulus-oocyte complex (COC) expansion and oocyte maturation are crucial processes for embryo development and fertility across species. Although miR-29b has been detected in porcine ovarian granulosa cells, its specific role in regulating oocyte maturation remains largely unknown. In this study, using the pig as a model, we report that over-expression of miR-29b lead to a decrease of COC expansion area and inhibits oocyte maturation (P<0.05). This suppression correlated with a decrease expression of COC-expansion-associated genes, including SHAS2, ADAMTS1, ADAMTS2, ADAMTS17 and PTX 3 in both mural granulosa cells (mGCs) and cumulus granulosa cells (cGCs). Further investigation revealed that miR-29b over-expression induces reactive oxygen species (ROS) accumulation in both mGCs and cGCs, conversely, knock-down of miR-29b reverses all these effects. Treatment with the antioxidant β-mercaptoethanol alleviates ROS accumulation, rescues COC expansion and restores oocyte polar body formation impaired by miR-29b mimics. Computational analysis predicted CYCS, the gene encoding cytochrome C, as a potential target of miR-29b. Subsequent examination demonstrated that miR-29b downregulates CYCS at both mRNA and protein levels. Dual-luciferase reporter assays further confirmed that miR-29b interacts with the 3'-untranslated region (3'UTR) of CYCS. Over-expression of CYCS decreases ROS accumulation and promotes COC expansion (P<0.05). These results indicate that miR-29b regulates COC expansion and oocyte maturation in vitro by inducing ROS, likely through targeting of CYCS. This study sheds light on the role of miR-29b in oocyte maturation and provides insight into the regulatory function of miRNAs in ovarian physiology.

Understanding the Role of miR-29a in the Regulation of RAG1, a Gene Associated with the Development of the Immune System

The process of Ag receptor diversity is initiated by RAGs consisting of RAG1 and RAG2 in developing lymphocytes. Besides its role as a sequence-specific nuclease during V(D)J recombination, RAGs can also act as a structure-specific nuclease leading to genome instability. Thus, regulation of RAG expression is essential to maintaining genome stability. Previously, the role of miR29c in the regulation of RAG1 was identified. In this article, we report the regulation of RAG1 by miR-29a in the lymphocytes of both mice (Mus musculus) and humans (Homo sapiens). The level of RAG1 could be modulated by overexpression of miR-29a and inhibition using anti-miRs. Argonaute2-immunoprecipitation and high-throughput sequencing of RNA isolated by crosslinking immunoprecipitation studies established the association of miR-29a and RAG1 with Argonaute proteins. We observed a negative correlation between miR-29a and RAG1 levels in mouse B and T cells and leukemia patients. Overexpression of pre-miR-29a in the bone marrow cells of mice led to the generation of mature miR-29a transcripts and reduced RAG1 expression, which led to a significant reduction in V(D)J recombination in pro-B cells. Importantly, our studies are consistent with the phenotype reported in miR-29a knockout mice, which showed impaired immunity and survival defects. Finally, we show that although both miR-29c and miR-29a can regulate RAG1 at mRNA and protein levels, miR-29a substantially impacts immunity and survival. Our results reveal that the repression of RAG1 activity by miR-29a in B cells of mice and humans is essential to maintain Ig diversity and prevent hematological malignancies resulting from aberrant RAG1 expression in lymphocytes.

Recent advances in understanding the human host immune response in tuberculous meningitis

Tuberculous meningitis (TBM), the most severe form of tuberculosis, causes death in approximately 25% cases despite antibiotic therapy, and half of survivors are left with neurological disability. Mortality and morbidity are contributed to by a dysregulated immune response, and adjunctive host-directed therapies are required to modulate this response and improve outcomes. Developing such therapies relies on improved understanding of the host immune response to TBM. The historical challenges in TBM research of limited in vivo and in vitro models have been partially overcome by recent developments in proteomics, transcriptomics, and metabolomics, and the use of these technologies in nested substudies of large clinical trials. We review the current understanding of the human immune response in TBM. We begin with M. tuberculosis entry into the central nervous system (CNS), microglial infection and blood-brain and other CNS barrier dysfunction. We then outline the innate response, including the early cytokine response, role of canonical and non-canonical inflammasomes, eicosanoids and specialised pro-resolving mediators. Next, we review the adaptive response including T cells, microRNAs and B cells, followed by the role of the glutamate-GABA neurotransmitter cycle and the tryptophan pathway. We discuss host genetic immune factors, differences between adults and children, paradoxical reaction, and the impact of HIV-1 co-infection including immune reconstitution inflammatory syndrome. Promising immunomodulatory therapies, research gaps, ongoing challenges and future paths are discussed.

Peripheral Transcriptomics in Acute and Long-Term Kidney Dysfunction in SARS-CoV2 Infection

Background

Acute kidney injury (AKI) is common in hospitalized patients with SARS-CoV2 infection despite vaccination and leads to long-term kidney dysfunction. However, peripheral blood molecular signatures in AKI from COVID-19 and their association with long-term kidney dysfunction are yet unexplored.

Methods

In patients hospitalized with SARS-CoV2, we performed bulk RNA sequencing using peripheral blood mononuclear cells(PBMCs). We applied linear models accounting for technical and biological variability on RNA-Seq data accounting for false discovery rate (FDR) and compared functional enrichment and pathway results to a historical sepsis-AKI cohort. Finally, we evaluated the association of these signatures with long-term trends in kidney function.

Results

Of 283 patients, 106 had AKI. After adjustment for sex, age, mechanical ventilation, and chronic kidney disease (CKD), we identified 2635 significant differential gene expressions at FDR<0.05. Top canonical pathways were EIF2 signaling, oxidative phosphorylation, mTOR signaling, and Th17 signaling, indicating mitochondrial dysfunction and endoplasmic reticulum (ER) stress. Comparison with sepsis associated AKI showed considerable overlap of key pathways (48.14%). Using follow-up estimated glomerular filtration rate (eGFR) measurements from 115 patients, we identified 164/2635 (6.2%) of the significantly differentiated genes associated with overall decrease in long-term kidney function. The strongest associations were 'autophagy', 'renal impairment via fibrosis', and 'cardiac structure and function'.

Conclusions

We show that AKI in SARS-CoV2 is a multifactorial process with mitochondrial dysfunction driven by ER stress whereas long-term kidney function decline is associated with cardiac structure and function and immune dysregulation. Functional overlap with sepsis-AKI also highlights common signatures, indicating generalizability in therapeutic approaches.

SIGNIFICANCE STATEMENT

Peripheral transcriptomic findings in acute and long-term kidney dysfunction after hospitalization for SARS-CoV2 infection are unclear. We evaluated peripheral blood molecular signatures in AKI from COVID-19 (COVID-AKI) and their association with long-term kidney dysfunction using the largest hospitalized cohort with transcriptomic data. Analysis of 283 hospitalized patients of whom 37% had AKI, highlighted the contribution of mitochondrial dysfunction driven by endoplasmic reticulum stress in the acute stages. Subsequently, long-term kidney function decline exhibits significant associations with markers of cardiac structure and function and immune mediated dysregulation. There were similar biomolecular signatures in other inflammatory states, such as sepsis. This enhances the potential for repurposing and generalizability in therapeutic approaches.

Diagnostic performance of microRNA-29a in active pulmonary tuberculosis: a systematic review and meta-analysis

BACKGROUND

In recent years, more and more studies have shown that microRNA-29a (miRNA-29a) can be used as a potential biomarker for active tuberculosis, but the results of these studies are not consistent.

OBJECTIVE

To comprehensively evaluate the value of miRNA-29a in the diagnosis of active tuberculosis by meta-analysis.

METHODS

The databases of CNKI, WanFang, PubMed, The Cochrane Library, Web of Science and EMBASE were searched for relevant studies. Studies were screened strictly according to inclusion and exclusion criteria. QUADAS-2 scale was used to evaluate the quality of the included studies. Data were extracted and analyzed by Meta-DiSc 1.4 and Stata 16.0 software.

RESULTS

13 articles were included, including a total of 1598 subjects, including 872 active tuberculosis patients and 726 controls. The combined sensitivity and specificity of miRNA-29a in the diagnosis of active tuberculosis were 78 % and 76 %, respectively, and the area under the overall summary receiver operating characteristic curve was 0.8564.

CONCLUSION

miRNA-29a can be used as a biomarker for the diagnosis of active tuberculosis.

Mathematical Models Including microRNA Levels of Mesenteric Adipose Tissue May Predict Postoperative Relapse in Crohn's Disease Patients

Background and Aims

Recent evidence suggests that the mesenteric adipose tissue (MAT) near the affected intestine may play a role in Crohn's disease (CD) pathophysiology. Modulation of several transcripts has already been identified in the MAT of CD in the literature. Therefore, our aim was to validate the microRNA (miRNA) transcript levels and their target genes in the MAT of active CD patients and correlate them with clinical and epidemiological data.

Methods

Samples from the MAT of surgical specimens from 25 active CD patients were obtained. The control group comprised fifteen patients who underwent surgery for other diseases, except inflammatory bowel diseases. Transcriptional levels of miRNA and their target genes were assessed by quantitative real-time polymerase chain reaction. The correlation between transcripts and clinical characteristics was obtained using multiple linear regression. The mathematical models (M) underwent a statistical filter to ensure robustness and reliability (P value < .05; adjusted R-squared (Rˆ2)> .99; correct predictions of more than 60%).

Results

miRNA-650 and miRNA-29c were upregulated in the MAT of CD compared to the control group (P < .0001 and P = .0032, respectively), besides presenting decreased levels of their target genes. Two were target genes of the miRNA-650: glutamine-fructose-6-phosphate transaminase 2 (P = .012) and aldehyde dehydrogenase 4 family (P = .0035); and 4 were targets of the miRNA-29c: cell death-inducing DFFA-like effector c (P = .001), E2F transcription factor-1 (P = .007), hypoxia-inducible factor 3 subunit alpha (P = .0029), and pyruvate dehydrogenase kinase 4 (P = .0054). We found 2 M with statistical strength and robustness. The performance test identified one model with 100% accuracy for predicting the month of recurrence and determining patients with less risk of early relapse after surgery.

Conclusion

We demonstrate that miRNA-650 and miRNA-29c and some of their target genes, besides clinical and epidemiological variables, may be useful in a model to predict when disease relapse may occur in CD patients who underwent surgery. These findings constitute a potential tool to guide postoperative clinical management.

Persistent and transient olfactory deficits in COVID-19 are associated to inflammation and zinc homeostasis

Introduction

The Coronavirus Disease 2019 (COVID-19) is mainly a respiratory syndrome that can affect multiple organ systems, causing a variety of symptoms. Among the most common and characteristic symptoms are deficits in smell and taste perception, which may last for weeks/months after COVID-19 diagnosis owing to mechanisms that are not fully elucidated.

Methods

In order to identify the determinants of olfactory symptom persistence, we obtained olfactory mucosa (OM) from 21 subjects, grouped according to clinical criteria: i) with persistent olfactory symptoms; ii) with transient olfactory symptoms; iii) without olfactory symptoms; and iv) non-COVID-19 controls. Cells from the olfactory mucosa were harvested for transcriptome analyses.

Results and discussion

RNA-Seq assays showed that gene expression levels are altered for a long time after infection. The expression profile of micro RNAs appeared significantly altered after infection, but no relationship with olfactory symptoms was found. On the other hand, patients with persistent olfactory deficits displayed increased levels of expression of genes involved in the inflammatory response and zinc homeostasis, suggesting an association with persistent or transient olfactory deficits in individuals who experienced SARS-CoV-2 infection.

MicroRNAs induced by Listeria monocytogenes and their role in cells

Listeria monocytogenes (Lm) causes abortions at high rates and threatens newborns' lives. Also, the elderly and immunocompromised individuals are particularly vulnerable neurologically. The bacterium exerts its pathogenesis intracellularly by manipulating cell organs. It manipulates nucleus elements, microRNAs (miRNAs), in order to increase survival and evade immunity. miRNAs are small non-coding RNAs that degrade gene expression post-transcriptionally. Any alteration to the expression of miRNAs affects various cascades in cells, especially immunity-related responses. Thus, utilizing miRNAs as a novel therapeutic agent not only restricts infection but enhances immunity reactions. This review provides an overview of miRNAs in listeriosis, their role in cells, and their prospects as therapy.

Role of microRNAs in type 2 diseases and allergen-specific immunotherapy

MicroRNAs (miRs) have gained scientific attention due to their importance in the pathophysiology of allergic diseases as well as their potential as biomarkers in allergen-specific treatment options. Their function as post-transcriptional regulators, controlling various cellular processes, is of high importance since any single miR can target multiple mRNAs, often within the same signalling pathway. MiRs can alter dysregulated expression of certain cellular responses and contribute to or cause, but in some cases prevent or repress, the development of various diseases. In this review article, we describe current research on the role of specific miRs in regulating immune responses in epithelial cells and specialized immune cells in response to various stimuli, in allergic diseases, and regulation in the therapeutic approach of allergen-specific immunotherapy (AIT). Despite the fact that AIT has been used successfully as a causative treatment option since more than a century, very little is known about the mechanisms of regulation and its connections with microRNAs. In order to fill this gap, this review aims to provide an overview of the current knowledge.

Circulating miRNAs in maternal plasma as potential biomarkers of early pregnancy in sheep

MicroRNA (miRNA) plays an important role in the control of gene expression and is implied in many biological functions, including embryo implantation and development. The aim was to assess plasma miRNA profiles during the peri-implantation and ascertain potential candidate miRNA markers for early pregnancy diagnosis in ovine plasma. The plasma samples were obtained from a total of 24 ewes on days 12 (pre-implantation; P12, n = 4), 16 (implantation; P16, n = 4) and 22 (post-implantation; P22, n = 4) after mating, and on their corresponding days of 12 (Pre-C; C12, n = 4), 16 (Imp-C; C16, n = 4) and 22 (Post-C; C22, n = 4) of the estrous cycle. The miRNA profiles in plasma were assessed by microarray technology. We detected the presence of 60 ovine-specific miRNAs in plasma samples. Of these miRNAs, 22 demonstrated a differential expression pattern, especially between the estrous cycle and early pregnancy, and targeted 521 genes. Two miRNAs (oar-miR-218a and oar-miR-1185-3p) were confirmed using RT-qPCR in the ovine plasma samples. Protein-protein interaction (PPI) network of target genes established six functional modules, of which modules 1 and 3 were enriched in the common GO terms, such as inflammatory response, defense response, and regulation of immune response. In contrast, module 2 was enriched in the developmental process involved in reproduction, embryo development, embryonic morphogenesis, and regulation of the developmental process. The results indicate that miRNAs profiles of plasma seemed to be modulated during the peri-implantation stage of pregnancy in ewes. Circulating miRNAs could be promising candidates for diagnosis in early ovine pregnancy.

MiR-29a-3p Improves Acute Lung Injury by Reducing Alveolar Epithelial Cell PANoptosis

Alveolar epithelial cell damage is an important determinant of the severity of acute lung injury/acute respiratory distress syndrome (ALI/ARDS). However, the molecular mechanisms of alveolar epithelial death during the development of ALI/ARDS remain unclear. In this study, we explore the role of miR-29a-3p in ALI/ARDS and its molecular mechanism. Plasma samples were collected from healthy controls and ARDS patients. Mice were intratracheally instilled with lipopolysaccharide (LPS) to establish acute lung injury. N6-adenosine (m6A) quantification, RNA-binding protein immunoprecipitation, cell viability assay, quantitative real-time polymerase chain reaction, and western blotting were performed. We found that miR-29a-3p was down-regulated in plasma of ARDS patients and lung tissue of ALI model mice, and miR-29a-3p agomir injection down-regulated the levels of the inflammatory factors, including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6) in the lungs, reducing alveolar epithelial cell PANoptosis as evaluated by the downregulation of Z-DNA binding protein 1 (ZBP1), gasdermin D (GSDMD), caspase-3, caspase-8, and mixed lineage kinase domain-like protein (MLKL), ultimately improving lung injury in the ALI model mice. Mechanism studies demonstrated that the knockout of methyltransferase 3 (N6-adenosine-methyltransferase complex catalytic subunit) removed the m6A modification of miR-29a-3p and reduced miR-29a-3p expression. Our findings suggest that miR-29a-3p is a potential target that can be manipulated for ALI/ARDS.

Expression and Secretion of Circular RNAs in the Parasitic Nematode, Ascaris suum

Circular RNAs (circRNAs) are a recently identified RNA species with emerging functional roles as microRNA (miRNA) and protein sponges, regulators of gene transcription and translation, and modulators of fundamental biological processes including immunoregulation. Relevant to this study, circRNAs have recently been described in the parasitic nematode, Haemonchus contortus, suggesting they may have functionally important roles in parasites. Given their involvement in regulating biological processes, a better understanding of their role in parasites could be leveraged for future control efforts. Here, we report the use of next-generation sequencing to identify 1,997 distinct circRNAs expressed in adult female stages of the gastrointestinal parasitic nematode, Ascaris suum. We describe spatial expression in the ovary-enriched and body wall muscle, and also report circRNA presence in extracellular vesicles (EVs) secreted by the parasite into the external environment. Further, we used an in-silico approach to predict that a subset of Ascaris circRNAs bind both endogenous parasite miRNAs as well as human host miRNAs, suggesting they could be functional as both endogenous and exogenous miRNA sponges to alter gene expression. There was not a strong correlation between Ascaris circRNA length and endogenous miRNA interactions, indicating Ascaris circRNAs are enriched for Ascaris miRNA binding sites, but that human miRNAs were predicted form a more thermodynamically stable bond with Ascaris circRNAs. These results suggest that secreted circRNAs could be interacting with host miRNAs at the host-parasite interface and influencing host gene transcription. Lastly, although we have previously found that therapeutically relevant concentrations of the anthelmintic drug ivermectin inhibited EV release from parasitic nematodes, we did not observe a direct effect of ivermectin treatment on Ascaris circRNAs expression or secretion.

MiRAGDB: A Knowledgebase of RAG Regulators

RAG1 and RAG2 genes generate diversity in immunoglobulin and TCR genes by initiating the process of V-D-J recombination. RAGs recognize specific sequences (heptamer-nonamer) to generate a diversity of immunoglobulins. RAG expression is limited to early B and T cell developmental stages. Aberrant expression of RAG can lead to double strand breaks and translocations as observed in leukemia and lymphoma. The expression of RAG is tightly regulated at the transcriptional and posttranscriptional levels. MicroRNAs (miRNAs) are small non-coding RNAs that are involved in the post-transcriptional regulation of gene expression. This study aimed to identify and catalog RAG regulation by miRNA during normal development and cancer. NGS data from normal B-cell and T-cell developmental stages and blood cancer samples have been analyzed for the expression of miRNAs against RAG1 (1,173 against human RAG1 and 749 against mouse RAG1). The analyzed data has been organized to retrieve the miRNA and mRNA expression of various RAG regulators (10 transcription factors and interacting partners) in normal and diseased states. The database allows users to navigate through the human and mouse RAG regulators, visualize and plot expression. miRAGDB is freely available and can be accessed at http://52.4.112.252/shiny/miragdb/.

MicroRNA-29 specifies age-related differences in the CD8+ T cell immune response

MicroRNAs (miRNAs) have emerged as critical regulators of cell fate in the CD8+ T cell response to infection. Although there are several examples of miRNAs acting on effector CD8+ T cells after infection, it is unclear whether differential expression of one or more miRNAs in the naive state is consequential in altering their long-term trajectory. To answer this question, we examine the role of miR-29 in neonatal and adult CD8+ T cells, which express different amounts of miR-29 only prior to infection and adopt profoundly different fates after immune challenge. We find that manipulation of miR-29 expression in the naive state is sufficient for age-adjusting the phenotype and function of CD8+ T cells, including their regulatory landscapes and long-term differentiation trajectories after infection. Thus, miR-29 acts as a developmental switch by controlling the balance between a rapid effector response in neonates and the generation of long-lived memory in adults.

MicroRNAs as Biomarkers for the Diagnosis of Ankylosing Spondylitis: A Systematic Review and Meta-Analysis

Background: Abnormal expression levels of microRNAs (miRNAs) were observed in ankylosing spondylitis (AS) in recent articles, suggesting that miRNAs may be used as biomarkers for AS diagnoses. In this paper, we conducted a meta-analysis to identify the overall diagnostic accuracy of miRNA biomarkers in AS patients. Methods: An extensive search was undertaken in PubMed, Embase, Cochrane databases, and Wan Fang database up to 30 December 2020 using the following key words: ("microRNAs" or "microRNA" or "miRNA" or "miR" or "RNA, Micro" or "Primary MicroRNA") and ("Spondylitis Ankylosing" or "Spondyloarthritis Ankylopoietica" or "Ankylosing Spondylarthritis" or "Ankylosing Spondylarthritides" or "Spondylarthritides Ankylosing" or "Ankylosing Spondylitis") and ("blood" or "serum" or "plasma"). Statistical evaluation of dysregulated miRNAs using the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and the area under the curve (AUC). Results: Twenty-nine articles reporting on the miRNAs of AS were included. A total of 42 miRNAs were observed to be up-regulated and 45 miRNAs were down-regulated in the AS cases compared with the controls. Besides, 29 studies from nine articles were included in our meta-analysis. The pooled sensitivity, specificity, PLR, NLR, DOR, and AUC were 0. 76 (95% CI, 0.70-0.81), 0.80 (95% CI, 0.74-0.85), 3.75 (95% CI, 2.82-5.01), 0.30 (95% CI, 0.24-0.39), 12.32 (95% CI, 7.65-19.83), 0.85 (95% CI, 0.81-0.88), respectively, suggesting a good diagnostic accuracy of miRNAs for AS. Conclusions: Circulating miRNAs are deregulated in AS patients. miRNAs may be used as a relatively non-invasive biomarkers for the detection of AS.

MicroRNA miR-29c regulates RAG1 expression and modulates V(D)J recombination during B cell development

Recombination activating genes (RAGs), consisting of RAG1 and RAG2, are stringently regulated lymphoid-specific genes, which initiate V(D)J recombination in developing lymphocytes. We report the regulation of RAG1 through a microRNA (miRNA), miR-29c, in a B cell stage-specific manner in mice and humans. Various lines of experimentation, including CRISPR-Cas9 genome editing, demonstrate the target specificity and direct interaction of miR-29c to RAG1. Modulation of miR-29c levels leads to change in V(D)J recombination efficiency in pre-B cells. The miR-29c expression is inversely proportional to RAG1 in a B cell developmental stage-specific manner, and miR-29c null mice exhibit a reduction in mature B cells. A negative correlation of miR-29c and RAG1 levels is also observed in leukemia patients, suggesting the potential use of miR-29c as a biomarker and a therapeutic target. Thus, our results reveal the role of miRNA in the regulation of RAG1 and its relevance in cancer.

The Epigenetic Modulation of Cancer and Immune Pathways in Hepatitis B Virus-Associated Hepatocellular Carcinoma: The Influence of HBx and miRNA Dysregulation

Hepatitis B virus (HBV)-associated hepatocellular carcinoma (HBV-HCC) pathogenesis is fueled by persistent HBV infection that stealthily maintains a delicate balance between viral replication and evasion of the host immune system. HBV is remarkably adept at using a combination of both its own, as well as host machinery to ensure its own replication and survival. A key tool in its arsenal, is the HBx protein which can manipulate the epigenetic landscape to decrease its own viral load and enhance persistence, as well as manage host genome epigenetic responses to the presence of viral infection. The HBx protein can initiate epigenetic modifications to dysregulate miRNA expression which, in turn, can regulate downstream epigenetic changes in HBV-HCC pathogenesis. We attempt to link the HBx and miRNA induced epigenetic modulations that influence both the HBV and host genome expression in HBV-HCC pathogenesis. In particular, the review investigates the interplay between CHB infection, the silencing role of miRNA, epigenetic change, immune system expression and HBV-HCC pathogenesis. The review demonstrates exactly how HBx-dysregulated miRNA in HBV-HCC pathogenesis influence and are influenced by epigenetic changes to modulate both viral and host genome expression. In particular, the review identifies a specific subset of HBx induced epigenetic miRNA pathways in HBV-HCC pathogenesis demonstrating the complex interplay between HBV infection, epigenetic change, disease and immune response. The wide-ranging influence of epigenetic change and miRNA modulation offers considerable potential as a therapeutic option in HBV-HCC.

Neuroimmune Mechanisms as Novel Treatment Targets for Substance Use Disorders and Associated Comorbidities

Recent studies examining the neurobiology of substance abuse have revealed a significant role of neuroimmune signaling as a mechanism through which drugs of abuse induce aberrant changes in synaptic plasticity and contribute to substance abuse-related behaviors. Immune signaling within the brain and the periphery critically regulates homeostasis of the nervous system. Perturbations in immune signaling can induce neuroinflammation or immunosuppression, which dysregulate nervous system function including neural processes associated with substance use disorders (SUDs). In this review, we discuss the literature that demonstrates a role of neuroimmune signaling in regulating learning, memory, and synaptic plasticity, emphasizing specific cytokine signaling within the central nervous system. We then highlight recent preclinical studies, within the last 5 years when possible, that have identified immune mechanisms within the brain and the periphery associated with addiction-related behaviors. Findings thus far underscore the need for future investigations into the clinical potential of immunopharmacology as a novel approach toward treating SUDs. Considering the high prevalence rate of comorbidities among those with SUDs, we also discuss neuroimmune mechanisms of common comorbidities associated with SUDs and highlight potentially novel treatment targets for these comorbid conditions. We argue that immunopharmacology represents a novel frontier in the development of new pharmacotherapies that promote long-term abstinence from drug use and minimize the detrimental impact of SUD comorbidities on patient health and treatment outcomes.

The role of miR-29 family in disease

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

miR-29 Sustains B Cell Survival and Controls Terminal Differentiation via Regulation of PI3K Signaling

The phosphatidylinositol 3-kinase (PI3K) signaling cascade downstream of the B cell receptor (BCR) signalosome is essential for B cell maturation. Proper signaling strength is maintained through the PI3K negative regulator phosphatase and tensin homolog (PTEN). Although a role for microRNA (miRNA)-dependent control of the PTEN-PI3K axis has been described, the contribution of individual miRNAs to the regulation of this crucial signaling modality in mature B lymphocytes remains to be elucidated. Our analyses reveal that ablation of miR-29 specifically in B lymphocytes results in an increase in PTEN expression and dampening of the PI3K pathway in mature B cells. This dysregulation has a profound impact on the survival of B lymphocytes and results in increased class switch recombination and decreased plasma cell differentiation. Furthermore, we demonstrate that ablation of one copy of Pten is sufficient to ameliorate the phenotypes associated with miR-29 loss. Our data suggest a critical role for the miR-29-PTEN-PI3K regulatory axis in mature B lymphocytes.

Which idea is better with regard to immune response? Opioid anesthesia or opioid free anesthesia

The stress of surgery is characterized by an inflammatory response with immune suppression resulting from many factors, including the type of surgery and the kind of anesthesia, linked with the drugs that are used and the underlying disease of the patient. The trauma of surgery triggers a cascade of reactions involving the immune response and nociception. As strong analgesics, opioids provide the analgesic component of general anesthesia with bi-directional effect on the immune system. Opioids influence almost all aspects of the immune response in regards to leukocytes, macrophages, mast cells, lymphocytes, and NK cells. The suppressive effect of opioids on the immune system is limiting their use, especially in patients with impaired immune response, so the possibility of using multimodal anesthesia without opioids, known as opioid-free anesthesia (OFA), is gaining more and more sympathizers. The idea of OFA is to eliminate opioid analgesia in the treatment of acute pain and to replace it with drugs from other groups that are assumed to have a comparable analgesic effect without affecting the immune system. Here, we present a review on the impact of anesthesia, with and without the use of opioids, on the immune response to surgical stress.

Decreased expression of miR-29 family associated with autoimmune myasthenia gravis

Background

Myasthenia gravis (MG) is a rare autoimmune disease mainly mediated by autoantibodies against the acetylcholine receptor (AChR) at the neuromuscular junction. The thymus is the effector organ, and its removal alleviates the symptoms of the disease. In the early-onset form of MG, the thymus displays functional and morphological abnormalities such as B cell infiltration leading to follicular hyperplasia, and the production of AChR antibodies. Type-I interferon (IFN-I), especially IFN-β, is the orchestrator of thymic changes observed in MG. As Dicer and miR-29 subtypes play a role in modulating the IFN-I signalization in mouse thymus, we investigated their expression in MG thymus.

Methods

The expression of DICER and miR-29 subtypes were thoroughly investigated by RT-PCR in human control and MG thymuses, and in thymic epithelial cells (TECs). Using miR-29a/b-1-deficient mice, with lower miR-29a/b-1 expression, we investigated their susceptibility to experimental autoimmune MG (EAMG) as compared to wild-type mice.

Results

DICER mRNA and all miR-29 subtypes were down-regulated in the thymus of MG patients and DICER expression was correlated with the lower expression of miR-29a-3p. A decreased expression of miR-29 subtypes was similarly observed in MG TECs; a decrease also induced in TECs upon IFN-β treatment. We demonstrated that miR-29a/b-1-deficient mice were more susceptible to EAMG without higher levels of anti-AChR IgG subtypes. In the thymus, if no B cell infiltration was observed, an increased expression of Ifn-β associated with Baff expression and the differentiation of Th17 cells associated with increased expression of Il-6, Il-17a and Il-21 and decreased Tgf-β1 mRNA were demonstrated in miR-29a/b-1-deficient EAMG mice.

Conclusions

It is not clear if the decreased expression of miR-29 subtypes in human MG is a consequence or a causative factor of thymic inflammation. However, our results from the EAMG mouse model indicated that a reduction in miR-29a/b1 may contribute to the pathophysiological process involved in MG by favoring the increased expression of IFN-β and the emergence of pro-inflammatory Th17 cells.

MiR-29 regulates the function of goat granulosa cell by targeting PTX3 via the PI3K/AKT/mTOR and Erk1/2 signaling pathways

PTX3, a member of the pentraxin protein family, plays important roles in ovulation as a marker of cumulus cell-oocyte complex expansion. However, the expression and function of PTX3 in goat ovarian GCs remain unclear. We isolated GCs from small and large follicles and found that PTX3 expression was significantly decreased and miR-29 mRNA expression was significantly increased during the growth of antral follicles. MiR-29 decreased PTX3 expression by targeting its 3' untranslated. Furthermore, miR-29 promoted GC proliferation, suppressed steroidogenesis and apoptosis by targeting PTX3 via the activation of the PI3K/AKT/mTOR and Erk1/2 signaling pathways. Treatment with inhibitors also verified these results. Meanwhile, we found that PI3K/AKT/mTOR and Erk1/2 signaling pathways had different role in secretion of E2 and P4 by regulating differently various steroidogenic enzyme (CYP19A1, CYP11A1, StAR and HSD3B) expression. These outcomes indicate the potential role of PTX3 in goat follicular growth and atresia.

The Multiple Roles of Hepatitis B Virus X Protein (HBx) Dysregulated MicroRNA in Hepatitis B Virus-Associated Hepatocellular Carcinoma (HBV-HCC) and Immune Pathways

Currently, the treatment of hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC) [HBV-HCC] relies on blunt tools that are unable to offer effective therapy for later stage pathogenesis. The potential of miRNA to treat HBV-HCC offer a more targeted approach to managing this lethal carcinoma; however, the complexity of miRNA as an ancillary regulator of the immune system remains poorly understood. This review examines the overlapping roles of HBx-dysregulated miRNA in HBV-HCC and immune pathways and seeks to demonstrate that specific miRNA response in immune cells is not independent of their expression in hepatocytes. This interplay between the two pathways may provide us with the possibility of using candidate miRNA to manipulate this interaction as a potential therapeutic option.

Downregulation of microRNA‑29c reduces pain after child delivery by activating the oxytocin‑GABA pathway

A significant decrease in the expression of spinal microRNA-29c (miR-29c), which is responsible for the regulation of oxytocin receptor (OXTR) expression, was observed in nerve injury pain during childbirth. The present study investigates whether spinal miR-29c could be a potential target for the treatment of pain, via the oxytocin (OT)-γ-aminobutyric acid (GABA) pathway. A spared nerve injury (SNI) rat model was established to induce neuropathic pain, simulating hyperalgesia. Spinal neurons were treated with OT to mimic the hormonal changes in the central nervous system after delivery. A change in the neuronal miniature inhibitory postsynaptic currents (mIPSCs) was observed in neurons, following the silencing of miR-29c or OT treatment with or without OXTR antagonist. The Von-Frey apparatus was used to measure the animal behaviors. Molecular biological experiments and electrophysical recordings in vivo and in vitro were performed to reveal the potential analgesic mechanisms. miR-29c was significantly downregulated (more than 8-fold) in the spinal dorsal horn of delivery+SNI rats compared with the SNI rats. The silencing of miR-29c resulted in increased pain threshold in SNI rats. Bioinformatics analysis indicated that OXTR was a potential target gene of miR-29c. The delivery+SNI rats presented with higher levels of OT in the cerebrospinal fluid compared with SNI rats, which indicated that the OT signaling pathway may participate in pain relief response. The increased expression of OXTR and GABA in delivery+SNI rats were observed in the miR-29c-silenced SNI rat model, suggesting that the silencing of miR-29c can mediate pain relief by enhancing the OT-GABA pathway. In addition, an electrophysiology assay was performed to assess the mIPSCs in neurons. The silencing of miR-29c in neurons increased the frequency and amplitude of mIPSCs but there was no influence on the decay time, which suggested that the spinal inhibitory neurons became more active, subsequently reducing the feeling of pain. The inhibition of OXTR reversed the enhanced inhibitory postsynaptic currents, indicating a crucial role for OXTR in the miR-29c-associated pain regulation. Taken together, the results of the present study suggested that spinal oxytocinergic inhibitory control plays an important role in pain relief in the neuropathic pain rat model undergoing vaginal delivery. Silencing spinal miR-29c may be a potential target for pain relief through the OT-GABA pathway.

microRNAs: key modulators of disease-modifying therapies in multiple sclerosis

There is a high level of heterogeneity in symptom manifestations and response to disease-modifying therapies (DMTs) in multiple sclerosis (MS), an immune-based neurodegenerative disease with ever-increasing prevalence in recent decades. Because of unknown aspects of the etiopathology of MS and mechanism of action of DMTs, the reason for this variability is undetermined, and much remains to be understood. Traditionally, physicians consider switching to other DMTs based on the exacerbation of symptoms and/or change in the results of magnetic resonance imaging and biochemical factors. Therefore, identifying biological treatment response markers that help us recognizing non-responders rapidly and subsequently choosing another DMTs is necessary. microRNAs (miRNAs) are micromanagers of gene expression which have been profiled in different samples of MS patients, highlighting their role in pathogenetic of MS. Recent studies have investigated expression profiling of miRNAs after treatment with DMTs to clarify possible DMTs-mediated mechanism and obtaining response to therapy biomarkers. In this review, we will discuss the modulation of miRNAs by DMTs in cells and pathways involved in MS.

Downregulated miR‑29a promotes B cell overactivation by upregulating Crk‑like protein in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is an autoimmune disorder; however, the pathogenesis is not fully understood. Accumulating evidence suggested an important role of microRNAs (miRNA/miR) in autoimmunity. The present study aimed therefore to determine the miRNA expression patterns in the B cells from the peripheral blood of 66 patients with SLE and 10 healthy controls (HCs) by using an Affymetrix GeneChip® miRNA 2.0 array. In addition, next‑generation sequencing was used to obtain the peripheral blood mononuclear cell (PBMC) miRNA profiles from three patients with SLE and three HCs. Candidate miRNAs that were considered to contribute to the pathogenesis of SLE were obtained based on the intersection of miRNA profiles. The analysis revealed a significant downregulation in miR‑29a expression levels in B cells from patients with SLE, which was subsequently verified using reverse transcription‑quantitative PCR. Based on these results, the expression pattern of miR‑29a in SLE was further investigated and its role in the hyperactivity of B cells was determined. miR‑29a inhibitors and mimics were transfected into PBMCs obtained from HCs and patients with SLE, and an ELISA was used to demonstrate that miR‑29a inhibition increased the production of IgG. Bioinformatics analysis predicted Crk‑like protein (CRKL) as a target gene of miR‑29a in patients with SLE. Therefore, CRKL expression levels were compared between patients with SLE and HCs by using western blotting, and its direct transcriptional regulation by miR‑29a was determined using a dual‑luciferase reporter assay. Low expression levels of miR‑29a were revealed to upregulate the expression levels of CRKL in B cells, and the protein expression levels of CRKL in patients with SLE were significantly upregulated compared with the HCs. In conclusion, the results from the present study suggested that miR‑29a may affect IgG antibody secretion in B cells by regulating CRKL, thereby contributing to the development and progression of SLE, which offers a novel candidate target for treatment.

MicroRNA Expression in Cutaneous Lupus: A New Window to Understand Its Pathogenesis

Background

The role of miRNAs in the pathogenesis of cutaneous lupus has not been studied.

Objective

It was to assess the levels of a selected panel of circulating miRNAs that could be involved in the regulation of the immune response, inflammation, and fibrosis in cutaneous lupus.

Methods

It was a cross-sectional study. We included 22 patients with subacute (SCLE) and 20 with discoid (DLE) lesions, and 19 healthy donors (HD). qRT-PCR for miRNA analysis, flow cytometry in peripheral blood, and skin immunohistochemistry were performed to determine the distribution of CD4 T cells and regulatory cells and their correlation with circulating miRNAs.

Results

miR-150, miR-1246, miR-21, miR-23b, and miR-146 levels were downregulated in SCLE vs. HD. miR-150, miR-1246, and miR-21 levels were downregulated in DLE vs. HD. miR-150, miR-1246, and miR-21 levels were downregulated in DLE γ⁺ with miR-1246 in SCLE, whereas CD123⁺/CD196⁺/IDO⁺ cells were positively associated with miR-150 in DLE. In the tissue, CD4⁺/IL-4⁺ and CD20⁺/IL-10⁺ cells were positively associated with miR-21 and CD4⁺/IFN-γ⁺ with miR-1246 in SCLE, whereas CD123⁺/CD196⁺/IDO⁺ cells were positively associated with miR-150 in DLE. In the tissue, CD4⁺/IL-4⁺ and CD20⁺/IL-10⁺ cells were positively associated with miR-21 and CD4⁺/IFN-β, thyroid hormone, and cancer signaling pathways were shared between miR-21, miR-31, miR-23b, miR-146a, miR-1246, and miR-150.

Conclusions

A downregulation of miR-150, miR-1246, and miR-21 in both CLE varieties vs. HD. miR-150, miR-1246, and miR-21 levels were downregulated in DLE

miR-140-3p exhibits repressive functions on preosteoblast viability and differentiation by downregulating MCF2L in osteoporosis

Previous research manifested that miR-140-3p was a latent biomarker for osteoporosis. Nevertheless, the mechanism of miR-140-3p in osteoporosis is still not clear and needs ulteriorly studying. The purpose of our paper was to ulteriorly probe the underlying mechanism of miR-140-3p on osteoporosis. Firstly, based on the data acquired from GEO database, we found that miR-140-3p was highly expressed; meanwhile, MCF2L was lowly expressed in osteoporosis patients. Upregulation/downregulation of miR-140-3p by miR-140-3p mimic/inhibitor restrained/promoted MC3T3-E1 cell viability and differentiation. However, miR-140-3p over-expression/downregulation accelerated/repressed MC3T3-E1 cell apoptosis. MCF2L was forecasted as a target of miR-140-3p by miRanda, miRWalk, and TargetScan miRNA target gene prediction software. Luciferase reporter assay confirmed that MCF2L could be directly targeted by miR-140-3p. Moreover, we identified that the expression of MCF2L was negatively regulated by miR-140-3p. From rescue assays, we discovered that knockdown of MCF2L weakened the promoting influence of miR-140-3p ablation on MC3T3-E1 cell viability and differentiation, and receded the suppressing impact of miR-140-3p reduction on MC3T3-E1 cell apoptosis. Above all, this research disclosed that miR-140-3p repressed preosteoblast viability and differentiation while promoted preosteoblast apoptosis via targeting MCF2L. Our discoveries might afford a theoretical basis of developing a latent novel target for osteoporosis therapy.

Identification of crucial genes in abdominal aortic aneurysm by WGCNA

Background

Abdominal aortic aneurysm (AAA) is the full thickness dilation of the abdominal aorta. However, few effective medical therapies are available. Thus, elucidating the molecular mechanism of AAA pathogenesis and exploring the potential molecular target of medical therapies for AAA is of vital importance.

Methods

Three expression datasets (GSE7084, GSE47472 and GSE57691) were downloaded from the Gene Expression Omnibus (GEO). These datasets were merged and then normalized using the “sva” R package. Differential expressed gene (DEG) analysis and weighted gene co-expression network analysis (WGCNA) were conducted. We compared the co-expression patterns between AAA and normal conditions, and hub genes of each functional module were identified. DEGs were mapped to co-expression network under AAA condition and a DEG co-expression network was generated. Crucial genes were identified using molecular complex detection (MCODE) (a plugin in Cytoscape).

Results

In our study, 6 and 10 gene modules were detected for the AAA and normal conditions, respectively, while 143 DEGs were screened. Compared to the normal condition, genes associated with immune response, inflammation and muscle contraction were clustered in three gene modules respectively under the AAA condition; the hub genes of the three modules were MAP4K1, NFIB and HPK1, respectively. A DEG co-expression network with 102 nodes and 303 edges was identified, and a hub gene cluster with 10 genes from the DEG co-expression network was detected. YIPF6, RABGAP1, ANKRD6, GPD1L, PGRMC2, HIGD1A, GMDS, MGP, SLC25A4 and FAM129A were in the cluster. The expression levels of these 10 genes showed potential diagnostic value.

Conclusion

Based on WGCNA, we detected 6 modules under the AAA condition and 10 modules in the normal condition. Hub genes of each module and hub gene clusters of the DEG co-expression network were identified. These genes may act as potential targets for medical therapy and diagnostic biomarkers. Further studies are needed to elucidate the detailed biological function of these genes in the pathogenesis of AAA.

Expression of microRNA in human retinal pigment epithelial cells following infection with Zaire ebolavirus

OBJECTIVE

Survivors of Ebola virus disease (EVD) are at risk of developing blinding intraocular inflammation-or uveitis-which is associated with retinal pigment epithelial (RPE) scarring and persistence of live Zaire ebolavirus (EBOV) within the eye. As part of a large research project aimed at defining the human RPE cell response to being infected with EBOV, this work focused on the microRNAs (miRNAs) associated with the infection.

RESULTS

Using RNA-sequencing, we detected 13 highly induced and 2 highly repressed human miRNAs in human ARPE-19 RPE cells infected with EBOV, including hsa-miR-1307-5p, hsa-miR-29b-3p and hsa-miR-33a-5p (up-regulated), and hsa-miR-3074-3p and hsa-miR-27b-5p (down-regulated). EBOV-miR-1-5p was also found in infected RPE cells. Through computational identification of putative miRNA targets, we predicted a broad range of regulatory activities, including effects on innate and adaptive immune responses, cellular metabolism, cell cycle progression, apoptosis and autophagy. The most highly-connected molecule in the miR-target network was leucine-rich repeat kinase 2, which is involved in neuroinflammation and lysosomal processing. Our findings should stimulate new studies on the impact of miRNA changes in EBOV-infected RPE cells to further understanding of intraocular viral persistence and the pathogenesis of uveitis in EVD survivors.

Insights into teleost interferon-gamma biology: An update

Interferon-gamma (IFN-ϒ) is probably one of the most relevant cytokines orchestrating the immune response in vertebrates. Although the activities mediated by this molecule are well known in mammals, several aspects of the IFN-ϒ system in teleosts remain a riddle to scientists. Numerous studies support a potentially similar role of the fish IFN-ϒ signalling pathway in some well-described immunological processes induced by this cytokine in mammals. Nevertheless, the existence in some teleost species of duplicated ifng genes and an additional gene derived from ifng known as interferon-γ-related (ifngrel), among other things, raises new interesting questions about the mode of action of these various molecules in fish. Moreover, certain IFN-ϒ-mediated activities recently observed in mammals are still fully unknown in fish. Another attractive but mainly unexplored curious property of IFN-ϒ in vertebrates is its potential dual role depending on the type of pathogen. In addition, some aspects mediated by this molecule could favour the resolution of a bacterial infection but be harmful in the context of a viral disease, and vice versa. This review collects old and new aspects of IFN-ϒ research in teleosts and discusses new questions and pathways of investigation based on recent discoveries in mammals.

Changes in Physiological Parameters, Lipid Metabolism, and Expression of MicroRNAs in Genetically Improved Farmed Tilapia (Oreochromis niloticus) With Fatty Liver Induced by a High-Fat Diet

Tilapia is susceptible to hepatic steatosis when grown in intensive farming systems. The aim of this study was to explore the mechanism of fatty liver induced by a high-fat diet (HFD) in genetically improved farmed tilapia (GIFT, Oreochromis niloticus). Juvenile GIFT were fed with HFD or a normal-fat diet (NFD) for 60 days. Substantial fat deposition in the liver of HFD-fed GIFT on days 20, 40, and 60 was observed using hematoxylin – eosin staining and oil red O staining. The increased fat deposition was consistent with increased triglyceride (TG) and total cholesterol (TC) levels in the liver of HFD-fed GIFT. There were significant differences (P < 0.05) in serum biochemical indexes (TG, TC, low density lipoprotein-cholesterol, and insulin contents, and alanine aminotransferase activity) between GIFT fed a HFD and GIFT fed a NFD on days 20, 40, and 60. Furthermore, 60 days of a HFD significantly changed (P < 0.05) the hepatic fatty acid composition, and led to increased polyunsaturated fatty acid levels and decreased saturated fatty acid and monounsaturated fatty acid levels. Hepatic antioxidant enzyme activities increased by day 20 and then declined, which led to an increase in malondialdehyde contents in the liver of HFD-fed GIFT. Molecular analyses revealed that the microRNAs miR-122, miR-29a, and miR-145-5p were upregulated, whereas miR-34a was downregulated in HFD-fed GIFT. SCD, ELOVL6, and SRD5A2 encode three important enzymes in lipid metabolism, and were identified as potential targets of miRNAs. The transcript levels of hepatic SCD and ELOVL6 were decreased and that of hepatic SRD5A2 was increased in GIFT fed a HFD. Overall, the results of this study revealed a potential link between miRNAs and fatty liver induced by HFD, and suggest that a HFD could lead to excess fat deposition in the GIFT liver, which may disrupt hepatic lipid metabolism and reduce the antioxidant defense capacity.

miR-29b directly targets activation-induced cytidine deaminase in human B cells and can limit its inappropriate expression in naïve B cells

Class-switch recombination (CSR) is an essential B cell process that alters the isotype of antibody produced by the B cell, tailoring the immune response to the nature of the invading pathogen. CSR requires the activity of the mutagenic enzyme AID (encoded by AICDA) to generate chromosomal lesions within the immunoglobulin genes that initiate the class switching recombination event. These AID-mediated mutations also participate in somatic-hypermutation of the immunoglobulin variable region, driving affinity maturation. As such, AID poses a significant oncogenic threat if it functions outside of the immunoglobulin locus. We found that expression of the microRNA, miR-29b, was repressed in B cells isolated from tonsil tissue, relative to circulating naïve B cells. Further investigation revealed that miR-29b was able to directly initiate the degradation of AID mRNA. Enforced overexpression of miR-29b in human B cells precipitated a reduction in overall AID protein and a corresponding diminution in CSR to IgE. Given miR-29b's ability to potently target AID, a mutagenic molecule that can initiate chromosomal translocations and "off-target" mutations, we propose that miR-29b acts to silence premature AID expression in naïve B cells, thus reducing the likelihood of inappropriate and potentially dangerous deamination activity.

MicroRNA-29b-2-5p inhibits cell proliferation by directly targeting Cbl-b in pancreatic ductal adenocarcinoma

Background

MicroRNAs can be used in the prognosis of malignancies; however, their regulatory mechanisms are unknown, especially in pancreatic ductal adenocarcinoma (PDAC).

Methods

In 120 PDAC specimens, miRNA levels were assessed by quantitative real time polymerase chain reaction (qRT-PCR). Then, the role of miR-29b-2-5p in cell proliferation was evaluated both in vitro (Trypan blue staining and cell cycle analysis in the two PDAC cell lines SW1990 and Capan-2) and in vivo using a xenograft mouse model. Next, bioinformatics methods, a luciferase reporter assay, Western blot, and immunohistochemistry (IHC) were applied to assess the biological effects of Cbl-b inhibition by miR-29b-2-5p. Moreover, the relationship between Cbl-b and p53 was evaluated by immunoprecipitation (IP), Western blot, and immunofluorescence.

Results

From the 120 PDAC patients who underwent surgical resection, ten patients with longest survival and ten with shortest survival were selected. We found that high miR-29b-2-5p expression was associated with good prognosis (p = 0.02). The validation cohort confirmed miR-29b-2-5p as an independent prognostic factor in PDAC (n = 100, 95% CI = 0.305–0.756, p = 0.002). Furthermore, miR-29b-2-5p inhibited cell proliferation, induced cell cycle arrest, and promoted apoptosis both in vivo and in vitro. Interestingly, miR-29b-2-5p directly bound the Cbl-b gene, down-regulating its expression and reducing Cbl-b-mediated degradation of p53. Meanwhile, miR-29b-2-5p expression was negatively correlated with Cbl-b in PDAC tissues (r = − 0.33, p = 0.001).

Conclusions

Taken together, these findings indicated that miR-29b-2-5p improves prognosis in PDAC by targeting Cbl-b to promote p53 expression, and would constitute an important prognostic factor in PDAC.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4526-z) contains supplementary material, which is available to authorized users.

Downregulated miR-17, miR-29c, miR-92a and miR-214 may be related to BCL11B overexpression in T cell acute lymphoblastic leukemia

AIM

BCL11B overexpression is a characteristic of most T cell acute lymphoblastic leukemia (T-ALL) cases, and downregulated BCL11B in leukemic T cells inhibits cell proliferation and induces apoptosis. The purpose of this study was to analyze the miRNA expression pattern that may be related to BCL11B regulation in T-ALL.

METHODS

Quantitative real-time PCR was used to detect the miRNAs miR-17-3p, miR-17-5p, miR-29c-3p, miR-92a-3p, miR-214-3p and miR-214-5p, the BCL11B expression level in peripheral blood mononuclear cells which was obtained from 17 de novo and untreated T-ALL patients, and 15 healthy individuals (HIs) served as control. Correlations between the relative miRNA expression levels and BCL11B were analyzed.

RESULTS

Based on the computational prediction that certain miRNAs bind the BCL11B 3'-UTR, miR-17-3p, miR-17-5p, miR-29c-3p, miR-92a-3p, miR-214-3p and miR-214-5p were found to be candidates for regulating BCL11B. The expression levels of the six miRNAs were decreased compared with HIs, and with the exception of miR-17-5p, statistically significant differences in expression levels were found in the T-ALL group. Moreover, while significantly higher BCL11B expression was found in the T-ALL group, a negative trend in the correlation level for all six miRNAs could be found in all groups; however, statistical significance was only found for miR-214-3p in the T-ALL group.

CONCLUSION

miRNA downregulation together with BCL11B upregulation suggests that miR-17, miR-29c, miR-92a and miR-214 might be involved in BCL11B regulation. The therapeutic promise of regulating the expression of these miRNAs for T-ALL therapy may be considered in the future.

MicroRNA‑29a is involved lipid metabolism dysfunction and insulin resistance in C2C12 myotubes by targeting PPARδ

MicroRNA‑29a (miR‑29a) expression has been reported to be closely associated with skeletal muscle insulin resistance and type 2 diabetes. The present study investigated the effect of miR‑29a on palmitic acid (PA)‑induced lipid metabolism dysfunction and insulin resistance in C2C12 myotubes via overexpressing or silencing of miR‑29a expression. Mouse C2C12 myoblasts were cultured, differentiated and transfected with miR‑29a or miR‑29a inhibitor lentiviral with or without subsequent palmitic acid (PA) treatment. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blot analysis were performed to assess the mRNA and protein levels of related genes, respectively. PA treatment increased the expression of miR‑29a in a time‑ and dose‑ dependent manner. miR‑29a silencing improved insulin‑induced glucose uptake and increased glucose transporter‑4 (GLUT4) transportation to the plasma membrane by upregulating its target peroxisome proliferator‑activated receptor δ (PPARδ). Furthermore, it was observed that miR‑29a regulated the expression of genes associated with lipid metabolism, including pyruvate dehydrogenase kinase isoform, mitochondrial uncoupling protein (UCP)2, UCP3, long chain specific acyl‑CoA dehydrogenase, mitochondrial and fatty acid transport protein 2. The results confirmed that silencing miR‑29a induced a decrease in glucose transport and affected lipid metabolism in PA‑treated C2C12 cells, and therefore may be involved in insulin resistance by targeting PPARδ in skeletal muscle. Therefore, the inhibition of miR‑29a may be a potential novel strategy for treating insulin resistance and type 2 diabetes.

MicroRNA-30a-3p overexpression improves sepsis-induced cell apoptosis in vitro and in vivo via the PTEN/PI3K/AKT signaling pathway

The aim of the present study was to explain the mechanism of miR-30a-3p overexpression in sepsis-induced cell apoptosis in vitro and in vivo. For the in vitro cell experiments, H9c2 cells were divided into three groups, including the untreated normal control (NC), lipopolysaccharide (LPS)-treated and miRNA (treated with LPS and transfection with miRNA-30a-3p) groups. The cell proliferation and apoptosis were evaluated by MTT assay and flow cytometry, respectively. The relative protein expression levels were measured by western blot assay. In the in vivo experiment, a sepsis rat model was established by intraperitoneal injection of LPS. Sprague Dawley rats were divided into three groups, including the NC, LPS-injected and miRNA (in which model rats were injected with miR-30a-3p vector at the caudal vein) groups. The myocardial morphology in different groups was observed by hematoxylin and eosin staining. In addition, tissue apoptosis and protein expression levels were evaluated by TUNEL and western blot assay, respectively. The results of cell experiments indicated that the cell proliferation rate was significantly increased and the cell apoptosis rate was significantly downregulated in the miR-30a-3p group compared with the LPS group (both P<0.05). The relative protein expression of phosphatase and tensin homolog (PTEN) was markedly decreased in the miRNA group compared with the LPS group, while the levels of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) were significantly increased in the miRNA group (all P<0.05). In the in vivo experiments, the myocardial morphology of the miRNA group was improved compared with that of the LPS group. Compared with the LPS group, cell apoptosis in the miRNA group was significantly downregulated (P<0.05), while the relative protein levels (PTEN, PI3K and AKT) in the tissues were also significantly altered (P<0.05). In conclusion, miR-30a-3p overexpression may improve the sepsis-induced cell apoptosis in vitro and in vivo via the PTEN/PI3K/AKT signaling pathway.

Microarray analysis to identify the similarities and differences of pathogenesis between aortic occlusive disease and abdominal aortic aneurysm

Objectives Expression profile of GSE57691 was analyzed to identify the similarities and differences between aortic occlusive disease and abdominal aortic aneurysm. Methods The expression profile of GSE57691 was downloaded from Gene Expression Omnibus database, including 20 small abdominal aortic aneurysm samples, 29 large abdominal aortic aneurysm samples, 9 aortic occlusive disease samples, and 10 control samples. Using the limma package in R, the differentially expressed genes were screened. Followed by enrichment analysis was performed for the differentially expressed genes using database for annotation, visualization, and integrated discovery online tool. Based on string online tool and Cytoscape software, protein-protein interaction network and module analyses were carried out. Moreover, integrated TF platform database and Cytoscape software were used for constructing transcriptional regulatory networks. Results As a result, 1757, 354, and 396 differentially expressed genes separately were identified in aortic occlusive disease, large abdominal aortic aneurysm, and small abdominal aortic aneurysm samples. UBB was significantly enriched in proteolysis related pathways with a high degree in three groups. SPARCL1 was another gene shared by these groups and regulated by NFIA, which had a high degree in transcriptional regulatory network. ACTB, a significant upregulated gene in abdominal aortic aneurysm samples, could be regulated by CLIC4, which was significantly enriched in cell motions. ACLY and NFIB were separately identified in aortic occlusive disease and small abdominal aortic aneurysm samples, and separately enriched in lipid metabolism and negative regulation of cell proliferation. Conclusions The downregulated UBB, NFIA, and SPARCL1 might play key roles in both aortic occlusive disease and abdominal aortic aneurysm, while the upregulated ACTB might only involve in abdominal aortic aneurysm. ACLY and NFIB were specifically involved in aortic occlusive disease and small abdominal aortic aneurysm separately.

A miRNA catalogue and ncRNA annotation of the short-living fish Nothobranchius furzeri

BACKGROUND

The short-lived fish Nothobranchius furzeri is the shortest-lived vertebrate that can be cultured in captivity and was recently established as a model organism for aging research. Small non-coding RNAs, especially miRNAs, are implicated in age dependent control of gene expression.

RESULTS

Here, we present a comprehensive catalogue of miRNAs and several other non-coding RNA classes (ncRNAs) for Nothobranchius furzeri. Analyzing multiple small RNA-Seq libraries, we show most of these identified miRNAs are expressed in at least one of seven Nothobranchius species. Additionally, duplication and clustering of N. furzeri miRNAs was analyzed and compared to the four fish species Danio rerio, Oryzias latipes, Gasterosteus aculeatus and Takifugu rubripes. A peculiar characteristic of N. furzeri, as compared to other teleosts, was a duplication of the miR-29 cluster.

CONCLUSION

The completeness of the catalogue we provide is comparable to that of the zebrafish. This catalogue represents a basis to investigate the role of miRNAs in aging and development in this species.

MicroRNA expression profiling of porcine mammary epithelial cells after challenge with Escherichia coli in vitro

Background

Coliform mastitis is a symptom of postpartum dysgalactia syndrome (PDS), a multifactorial infectious disease of sows. Our previous study showed gene expression profile change after bacterial challenge of porcine mammary epithelial cells (PMECs). These mRNA expression changes may be regulated through microRNAs (miRNAs) which play critical roles in biological processes. Therefore, miRNA expression profile was investigated in PMECs.

Results

PMECs were isolated from three lactating sows and challenged with heat-inactivated potential mastitis-causing pathogen Escherichia coli (E. coli) for 3 h and 24 h, in vitro. At 3 h post-challenge with E. coli, target gene prediction identified a critical role of miRNAs in regulation of host immune responses and homeostasis of PMECs mediated by affecting pathways including cytokine binding (miR-202, miR-3277, miR-4903); IL-10/PPAR signaling (miR-3277, miR-4317, miR-548); and NF-ĸB/TNFR2 signaling (miR-202, miR-2262, miR-885-3p). Target genes of miRNAs in PMECs at 24 h were significantly enriched in pathways associated with interferon signaling (miR-210, miR-23a, miR-1736) and protein ubiquitination (miR-125, miR-128, miR-1280).

Conclusions

This study provides first large-scale miRNA expression profiles and their predicted target genes in PMECs after contact with a potential mastitis-causing E. coli strain. Both, highly conserved miRNAs known from other species as well as novel miRNAs were identified in PMECs, representing candidate predictive biomarkers for PDS. Time-dependent pathogen clearance suggests an important role of PMECs in inflammatory response of the first cellular barrier of the porcine mammary gland.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-017-4070-2) contains supplementary material, which is available to authorized users.

MicroRNA-210, MicroRNA-331, and MicroRNA-7 Are Differentially Regulated in Treated HIV-1-Infected Individuals and Are Associated With Markers of Systemic Inflammation

OBJECTIVE

Inflammation may contribute to an increased risk of cardiovascular disease (CVD) in HIV-1 infection. MicroRNAs (miRNAs) are involved in the regulation of inflammation. In treated HIV-1-infected individuals, we aimed to identify differentially expressed miRNAs with known roles in inflammation and CVD risk and to investigate associations between these and systemic inflammation.

METHODS

In a screening cohort including 14 HIV-1-infected individuals and 9 uninfected controls, microarray profiling was performed using peripheral blood mononuclear cells (PBMCs). Differentially regulated miRNAs previously related to inflammation and CVD were validated using real-time quantitative reverse-transcription polymerase chain reaction in 26 HIV-1-infected individuals and 20 uninfected controls. Validated miRNAs were measured in PBMCs, CD4 and CD8 T cells. Interleukin-6, tumor necrosis factor-alpha, high-sensitivity C-reactive protein, lipopolysaccharide (LPS), cytomegalovirus immunoglobulin G, lipids, and fasting glucose were measured, and associations with validated miRNAs were assessed with multiple linear regression analysis.

RESULTS

Upregulation of miR-210, miR-7, and miR-331 was found in PBMCs from HIV-1-infected individuals when compared with those from uninfected controls (P < 0.005). In contrast, miR-210 and miR-331 were downregulated in CD8 T cells. In multivariate analysis, miR-210 in CD8 T cells was negatively associated with LPS (P = 0.023) and triglycerides (P = 0.003) but positively associated with tumor necrosis factor-alpha (P = 0.004). MiR-7 in PBMC was positively associated with interleukin-6 (P = 0.025) and fasting glucose (P = 0.005), whereas miR-331 was negatively associated with LPS (P = 0.006). In PBMCs from HIV-1-infected individuals with low cytomegalovirus immunoglobulin G, miR-7, miR-29a, miR-221, and miR-222 were downregulated.

CONCLUSION

In 2 independent cohorts, miR-210, miR-7, and miR-331 were differentially regulated in treated HIV-1-infected individuals and associated with markers of systemic inflammation.

Defective germinal center B-cell response and reduced arthritic pathology in microRNA-29a-deficient mice

MicroRNA (miR) are short non-coding RNA sequences of 19-24 nucleotides that regulate gene expression by binding to mRNA target sequences. The miR-29 family of miR (miR-29a, b-1, b-2 and c) is a key player in T-cell differentiation and effector function, with deficiency causing thymic involution and a more inflammatory T-cell profile. However, the relative roles of different miR-29 family members in these processes have not been dissected. We studied the immunological role of the individual members of the miR-29 family using mice deficient for miR-29a/b-1 or miR-29b-2/c in homeostasis and during collagen-induced arthritis. We found a definitive hierarchy of immunological function, with the strong phenotype of miR-29a-deficiency in thymic involution and T-cell activation being reduced or absent in miR-29c-deficient mice. Strikingly, despite elevating the Th1 and Th17 responses, loss of miR-29a conferred near-complete protection from collagen-induced arthritis (CIA), with profound defects in B-cell proliferation and antibody production. Our results identify the hierarchical structure of the miR-29 family in T-cell biology, and identify miR-29a in B cells as a potential therapeutic target in arthritis.

microRNA expression changes after lipopolysaccharide treatment in gills of amphioxus Branchiostoma belcheri

Recently, amphioxus has served as a model for studying the origin and evolution of vertebrate immunity. However, little is known about how microRNAs (miRNAs) are involved in the immune defense in amphioxus. In this article, we identified the amphioxus miRNAs in the acute-phase response to lipopolysaccharide (LPS). We determined the time point for the peak of immune response in amphioxus after LPS challenge by evaluating the expression of Branchiostoma belcheri toll-like receptor 1, NF-κb (c-Rel), and big defensin which react with pathogen-associated molecular patterns(PAMPs). Then we chose 12 h as the point to perform miRNA microarray analysis to select the differentially expressed miRNAs. Furthermore, we used quantitative real-time PCR to detect the expression patterns of selected amphioxus miRNAs under effective LPS challenge during the time course. The microarray data revealed that the miRNA expression file was significantly changed after LPS stimulation. The changes of the 10 most upregulated and 7 most downregualted miRNAs in gills of the amphioxus following challenge with LPS revealed a temporal induction kinetic. Our current study will provide valuable information to take an insight into molecular mechanism of innate immune and the evolution of the miRNA family.

miR-29a-deficiency does not modify the course of murine pancreatic acinar carcinoma

The development of cancers involves the complex dysregulation of multiple cellular processes. With key functions in simultaneous regulation of multiple pathways, microRNA (miR) are thought to have important roles in the oncogenic formation process. miR-29a is among the most abundantly expressed miR in the pancreas. Together with altered expression in pancreatic cancer cell lines and biopsies, and known oncogenic functions in leukemia, this expression data has identified miR-29a as a key candidate for miR involvement in pancreatic cancer biology. Here we used miR-29a-deficient mice and the TAg model of pancreatic acinar carcinoma to functionally test the role of miR-29a in vivo. We found no impact of miR-29a loss on the development or growth of pancreatic tumours, nor on the survival of tumour-bearing mice. These results suggest that, despite differential expression, miR-29a is oncogenically neutral in the pancreatic acinar carcinoma context. If these results are extended to other models of pancreatic cancer, they would reduce the attractiveness of miR-29a as a potential therapeutic target in pancreatic cancer.

MicroRNA miR-29 controls a compensatory response to limit neuronal iron accumulation during adult life and aging

Background

A widespread modulation of gene expression occurs in the aging brain, but little is known as to the upstream drivers of these changes. MicroRNAs emerged as fine regulators of gene expression in many biological contexts and they are modulated by age. MicroRNAs may therefore be part of the upstream drivers of the global gene expression modulation correlated with aging and aging-related phenotypes.

Results

Here, we show that microRNA-29 (miR-29) is induced during aging in short-lived turquoise killifish brain and genetic antagonism of its function induces a gene-expression signature typical of aging. Mechanicistically, we identified Ireb2 (a master gene for intracellular iron delivery that encodes for IRP2 protein), as a novel miR-29 target. MiR-29 is induced by iron loading and, in turn, it reduces IRP2 expression in vivo, therefore limiting intracellular iron delivery in neurons. Genetically modified fish with neuro-specific miR-29 deficiency exhibit increased levels of IRP2 and transferrin receptor, increased iron content, and oxidative stress.

Conclusions

Our results demonstrate that age-dependent miR-29 upregulation is an adaptive mechanism that counteracts the expression of some aging-related phenotypes and its anti-aging activity is primarily exerted by regulating intracellular iron homeostasis limiting excessive iron-exposure in neurons.

Electronic supplementary material

The online version of this article (doi:10.1186/s12915-017-0354-x) contains supplementary material, which is available to authorized users.

miR-29a modulates SCD expression and is regulated in response to a saturated fatty acid diet in juvenile genetically improved farmed tilapia (Oreochromis niloticus)

MicroRNAs (miRNAs) are small non-coding RNAs that regulate target gene expression by binding to the 3′ untranslated region (3′ UTR) of the target mRNA. MiRNAs regulate a large variety of genes, including those involved in liver biology and disease. Here, we report for the first time that miR-29a post-transcriptionally regulates stearoyl-CoA desaturase (SCD) by binding to its 3′ UTR in genetically improved farmed tilapia (GIFT), Oreochromis niloticus, as shown by a 3′ UTR luciferase reporter assay. miR-29a antagomir treatment in vivo resulted in significant upregulation of SCD expression. We found that miR-29a expression was negatively correlated with SCD expression in GIFT liver. Inhibition of miR-29a led to a significant increase in SCD expression on day 60 induced by a saturated fatty acid diet, thereby increasing conversion of 16:0 and 18:0 to 16:1 and 18:1, respectively, and activating serum insulin, which would favor glucose and lipid uptake by the liver. These results indicate that miR-29a regulates SCD levels by binding to its 3′ UTR, and this interaction affects saturated fatty acid stress induction and insulin and lipid accumulation in serum. Our results suggest that miR-29a is critical in regulating lipid metabolism homeostasis in GIFT liver, and this might provide a basis for understanding the biological processes and therapeutic intervention encountered in fatty liver.

Summary: miR-29a targets SCD 3′ UTR directly. Inhibition of miR-29a could mediate conversion of C16:0 and C18:0 to C16:1 and C18:1, respectively, and activate serum insulin and glucose uptake in GIFT by increasing SCD.

Serum miR-29a Is Upregulated in Acute Graft-versus-Host Disease and Activates Dendritic Cells through TLR Binding

Acute graft-versus-host disease (aGVHD) continues to be a frequent and devastating complication of allogeneic hematopoietic stem cell transplantation (HSCT), posing as a significant barrier against the widespread use of HSCTs as a curative modality. Recent studies suggested serum/plasma microRNAs (miRs) may predict aGVHD onset. However, little is known about the functional role of circulating miRs in aGVHD. In this article, we show in two independent cohorts that miR-29a expression is significantly upregulated in the serum of allogeneic HSCT patients at aGVHD onset compared with non-aGVHD patients. Serum miR-29a is also elevated as early as 2 wk before time of diagnosis of aGVHD compared with time-matched control subjects. We demonstrate novel functional significance of serum miR-29a by showing that miR-29a binds and activates dendritic cells via TLR7 and TLR8, resulting in the activation of the NF-κB pathway and secretion of proinflammatory cytokines TNF-α and IL-6. Treatment with locked nucleic acid anti-miR-29a significantly improved survival in a mouse model of aGVHD while retaining graft-versus-leukemia effects, unveiling a novel therapeutic target in aGVHD treatment or prevention.