Inverse correlation of expression of microRNA-140-5p with progression of multiple sclerosis and differentiation of encephalitogenic T helper type 1 cells

Increased IL-22 in cerebrospinal fluid of neuro-behçet's disease patients

Remitting-Relapsing Multiple Sclerosis (RRMS) and Neuro-Behçet Disease (NBD) are two chronic neuro-inflammatory disorders leading to brain damage and disability in young adults. Herein, we investigated in these patients the cytokine response by beads-based multiplex assays during the early stages of these disorders. Cytokine investigations were carried out on treatment-naive patients suffering from RRMS and NBD recruited at the first episode of clinical relapse. Our findings demonstrate that Cerebrospinal Fluid (CSF) cells from NBD patients, but not RRMS, secrete significant high levels of IL-22 which is associated with elevated IL-22 mRNA expression. We also observed an increase in IL-22 levels in the definite NBD subgroup as compared to the probable NBD one, indicating a clear relationship between elevated IL-22 levels and diagnostic certainty. Interestingly, we found no correlation of IL-22 secretion between CSF and serum arguing about intrathecal release of IL-22 in the CNS of NBD patients. Moreover, we showed by correlogram analysis that this cytokine doesn't correlate with IL-17A, IL-17F and IL-21 suggesting that this cytokine is secreted by Th22 cells and not by Th17 cells in the CSF of NBD patients. Finally, we found elevated levels of IL-6 and a positive correlation between IL and 6 and IL-22 in the CSF of NBD. In conclusion, these results suggest that IL-6 contributes to the production of IL-22 by T cells leading to the exacerbation of inflammation and damage within the CNS of NBD patients.

The role of miRNAs in T helper cell development, activation, fate decisions and tumor immunity

T helper (Th) cells are central members of adaptive immunity and comprise the last line of defense against pathogen infection and malignant cell invasion by secreting specific cytokines. These cytokines then attract or induce the activation and differentiation of other immune cells, including antibody-producing B cells and cytotoxic CD8+ T cells. Therefore, the bidirectional communication between Th cells and tumor cells and their positioning within the tumor microenvironment (TME), especially the tumor immune microenvironment (TIME), sculpt the tumor immune landscape, which affects disease initiation and progression. The type, number, and condition of Th cells in the TME and TIME strongly affect tumor immunity, which is precisely regulated by key effectors, such as granzymes, perforins, cytokines, and chemokines. Moreover, microRNAs (miRNAs) have emerged as important regulators of Th cells. In this review, we discuss the role of miRNAs in regulating Th cell mediated adaptive immunity, focusing on the development, activation, fate decisions, and tumor immunity.

MicroRNA-140-5p inhibitor attenuates memory impairment induced by amyloid-ß oligomer in vivo possibly through Pin1 regulation

AIMS

The peptidyl-prolyl cis/trans isomerase, Pin1, has a protective role in age-related neurodegeneration by targeting different phosphorylation sites of tau and the key proteins required to produce Amyloid-β, which are the well-known molecular signatures of Alzheimer's disease (AD) neuropathology. The direct interaction of miR-140-5p with Pin1 mRNA and its inhibitory role in protein translation has been identified. The main purpose of this study was to investigate the role of miRNA-140-5p inhibition in promoting Pin1 expression and the therapeutic potential of the AntimiR-140-5p in the Aß oligomer (AßO)-induced AD rat model.

METHODS

Spatial learning and memory were assessed in the Morris water maze. RT-PCR, western blot, and histological assays were performed on hippocampal samples at various time points after treatments. miRNA-140-5p inhibition enhanced Pin1 and ADAM10 mRNA expressions but has little effect on Pin1 protein level.

RESULTS

The miRNA-140-5p inhibitor markedly ameliorated spatial learning and memory deficits induced by AßO, and concomitantly suppressed the mRNA expression of inflammatory mediators TNFα and IL-1β, and phosphorylation of tau at three key sites (thr231, ser396, and ser404) as well as increased phosphorylated Ser473-Akt.

CONCLUSION

According to our results, Antimir-140-mediated improvement of AβO-induced neuronal injury and memory impairment in rats may provide an appropriate rationale for evaluating miR-140-5p inhibitors as a promising agent for the treatment of AD.

An Update on Diagnostic Laboratory Biomarkers for Multiple Sclerosis

PURPOSE

For many patients, the multiple sclerosis (MS) diagnostic process can be lengthy, costly, and fraught with error. Recent research aims to address the unmet need for an accurate and simple diagnostic process through discovery of novel diagnostic biomarkers. This review summarizes recent studies on MS diagnostic fluid biomarkers, with a focus on blood biomarkers, and includes discussion of technical limitations and practical applicability.

RECENT FINDINGS

This line of research is in its early days. Accurate and easily obtainable biomarkers for MS have not yet been identified and validated, but several approaches to uncover them are underway. Continue efforts to define laboratory diagnostic biomarkers are likely to play an increasingly important role in defining MS at the earliest stages, leading to better long-term clinical outcomes.

Serum-Derived Exosomal miR-140-5p as a Promising Biomarker for Differential Diagnosis of Anti-NMDAR Encephalitis With Viral Encephalitis

Background

Anti-N-methyl-D-aspartate receptor (anti-NMDAR) encephalitis is the most common type of autoimmune encephalitis. Early recognition and treatment, especially distinguishing from viral encephalitis (VE) in the early stages, are crucial for the outcomes of patients with anti-NMDAR encephalitis. Compared with plasma microRNAs (miRNAs), exosomal miRNAs are more abundant and not easy to degrade. Moreover, exosomes can pass through the blood–brain barrier. This study aimed to explore the clinical value of serum exosomal miRNAs in the differential diagnosis of anti-NMDAR encephalitis with VE.

Method

Serum samples from a total of 30 patients with anti-NMDAR encephalitis, 30 patients with VE, and 30 cases of control patients hospitalized in the same period were collected. Firstly, the serum exosomes were isolated and identified by transmission electron microscope (TEM), nanoparticle-tracking analyzer (NTA), and Western blot (WB). The expression levels of let-7b and miR-140-5p from serum exosomes were detected by real-time quantitative PCR (qPCR). At the same time, we also detected complement 3 (C3), complement 4 (C4), and high sensitivity CRP (hs-CRP) expression levels in three groups. Finally, we analyzed the difference and diagnostic value of the test results.

Results

Isolated particles showed identical characteristics to the exosomes through TEM, NTA, and WB analyses. Compared with the VE group and control group, the expression of miR-140-5p was significantly upregulated in serum exosomes of the NMDAR group. In contrast, the serum C3 in the NMDAR group was significantly lower than the other two groups. ROC curve analysis showed the area under the curve (AUC) of serum exosomal miR-140-5p and serum C3 was 0.748 (76.67% sensitivity and 73.33% specificity) and 0.724 (76.67% sensitivity and 60% specificity) to distinguish anti-NMDAR encephalitis from VE, respectively. The AUC of serum exosomal miR-140-5p combined with serum C3 was 0.811, the sensitivity was 70.00%, and the specificity was 86.67%.

Conclusion

Serum exosomal miR-140-5p combined with serum C3 would be a promising marker in the differential diagnosis of anti-NMDAR encephalitis with VE.

MicroRNAs as T Lymphocyte Regulators in Multiple Sclerosis

MicroRNA (miRNA) is a class of endogenous non-coding small RNA with regulatory activities, which generally regulates the expression of target genes at the post-transcriptional level. Multiple Sclerosis (MS) is thought to be an autoimmune-mediated chronic inflammatory demyelinating disease of the central nervous system (CNS) that typically affect young adults. T lymphocytes play an important role in the pathogenesis of MS, and studies have suggested that miRNAs are involved in regulating the proliferation, differentiation, and functional maintenance of T lymphocytes in MS. Dysregulated expression of miRNAs may lead to the differentiation balance and dysfunction of T lymphocytes, and they are thus involved in the occurrence and development of MS. In addition, some specific miRNAs, such as miR-155 and miR-326, may have potential diagnostic values for MS or be useful for discriminating subtypes of MS. Moreover, miRNAs may be a promising therapeutic strategy for MS by regulating T lymphocyte function. By summarizing the recent literature, we reviewed the involvement of T lymphocytes in the pathogenesis of MS, the role of miRNAs in the pathogenesis and disease progression of MS by regulating T lymphocytes, the possibility of differentially expressed miRNAs to function as biomarkers for MS diagnosis, and the therapeutic potential of miRNAs in MS by regulating T lymphocytes.

Non-coding RNAs in the Pathogenesis of Multiple Sclerosis

Multiple sclerosis (MS) is an early onset chronic neurological condition in adults characterized by inflammation, demyelination, gliosis, and axonal loss in the central nervous system. The pathological cause of MS is complex and includes both genetic and environmental factors. Non-protein-coding RNAs (ncRNAs), specifically miRNAs and lncRNAs, are important regulators of various biological processes. Over the past decade, many studies have investigated both miRNAs and lncRNAs in patients with MS. Since then, insightful knowledge has been gained in this field. Here, we review the role of miRNAs and lncRNAs in MS pathogenesis and discuss their implications for diagnosis and treatment.

Long non-coding RNA growth arrest-specific 5 and its targets, microRNA-21 and microRNA-140, are potential biomarkers of allergic rhinitis

Objective

Long non‐coding RNA growth arrest‐specific 5 (lnc‐GAS5) and its targets (microRNA [miR]‐21 and miR‐140) are involved in the development and progression of allergic rhinitis (AR). However, the correlation of lnc‐GAS5 with miR‐21 and miR‐140 and their associations with disease risk, symptom severity, and Th1/Th2 cytokines in AR remain unclear. Thus, this study aimed to investigate this topic.

Methods

In total, 120 patients with AR and 60 controls were recruited. Nasal‐mucosa tissues were collected from all participants. Lnc‐GAS5, its targets (miR‐21 and miR‐140), interferon (IFN)‐γ, interleukin (IL)‐2, IL‐4, and IL‐10 were detected by reverse‐transcription quantitative polymerase chain reaction.

Results

Lnc‐GAS5 was elevated, while miR‐21 and miR‐140 was downregulated in AR patients than in controls (p < 0.001). In AR patients, lnc‐GAS5 was negatively correlated with miR‐21 (p < 0.001), miR‐140 (p < 0.001), IFN‐γ (p = 0.019), and IL‐2 (p = 0.039) and positively correlated with IL‐4 (p = 0.004) and IL‐10 (p < 0.001), individual nasal symptom scores (INSSs) for itching, sneezing, and congestion (p < 0.05), and total nasal symptom score (TNSS) (p < 0.001). Moreover, miR‐21 and miR‐140 were negatively correlated with some INSSs, total TNSS score, and IL‐10 and positively correlated with IFN‐γ and IL‐2 (p < 0.05).

Conclusion

Lnc‐GAS5 is negatively correlated with that of its targets (miR‐21 and miR‐140) in AR; meanwhile, lnc‐GAS5, miR‐21, and miR‐140 are correlated with disease risk, symptom severity, and Th1/Th2 imbalance in AR, suggesting the potential of these biomarkers in the development and progression of AR.

Cerebrospinal fluid cells immune landscape in multiple sclerosis

Background

Multiple Sclerosis (MS) is a potentially devastating autoimmune neurological disorder, which characteristically induces demyelination of white matter in the brain and spinal cord.

Methods

In this study, three characteristics of the central nervous system (CNS) immune microenvironment occurring during MS onset were explored; immune cell proportion alteration, differential gene expression profile, and related pathways. The raw data of two independent datasets were obtained from the ArrayExpress database; E-MTAB-69, which was used as a derivation cohort, and E-MTAB-2374 which was used as a validation cohort. Differentially expressed genes (DEGs) were identified by the false discovery rate (FDR) value of < 0.05 and |log2 (Fold Change)|> 1, for further analysis. Then, functional enrichment analyses were performed to explore the pathways associated with MS onset. The gene expression profiles were analyzed using CIBERSORT to identify the immune type alterations involved in MS disease.

Results

After verification, the proportion of five types of immune cells (plasma cells, monocytes, macrophage M2, neutrophils and eosinophils) in cerebrospinal fluid (CSF) were revealed to be significantly altered in MS cases compared to the control group. Thus, the complement and coagulation cascades and the systemic lupus erythematosus (SLE) pathways may play critical roles in MS. We identified NLRP3, LILRB2, C1QB, CD86, C1QA, CSF1R, IL1B and TLR2 as eight core genes correlated with MS.

Conclusions

Our study identified the change in the CNS immune microenvironment of MS cases by analysis of the in silico data using CIBERSORT. Our data may assist in providing directions for further research as to the molecular mechanisms of MS and provide future potential therapeutic targets in treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12967-021-02804-7.

AhR Ligands Differentially Regulate miRNA-132 Which Targets HMGB1 and to Control the Differentiation of Tregs and Th-17 Cells During Delayed-Type Hypersensitivity Response

Aryl hydrocarbon receptor (AhR), is a transcription factor and an environmental sensor that has been shown to regulate T cell differentiation. Interestingly, AhR ligands exert varying effects from suppression to exacerbation of inflammation through induction of Tregs and Th-17 cells, respectively. In the current study, we investigated whether the differential effects of AhR ligands on T cell differentiation are mediated by miRNA during delayed-type hypersensitivity (DTH) reaction against methylated Bovine Serum Albumin (mBSA). Treatment of C57BL/6 mice with TCDD attenuated mBSA-mediated DTH response, induced Tregs, decreased Th-17 cells, and caused upregulation of miRNA-132. TCDD caused an increase in several Treg subsets including inducible peripheral, natural thymic, and Th3 cells. Also, TCDD increased TGF-β and Foxp3 expression. In contrast, treating mice with FICZ exacerbated the DTH response, induced inflammatory Th17 cells, induced IL-17, and RORγ. Analysis of miRNA profiles from draining lymph nodes showed that miR-132 was upregulated in the TCDD group and downregulated in the FICZ group. Transfection studies revealed that miRNA-132 targeted High Mobility Group Box 1 (HMGB1). Downregulation of HMGB1 caused an increase in FoxP3+ Treg differentiation and suppression of Th-17 cells while upregulation of HMGB1 caused opposite effects. Moreover, TCDD was less effective in suppressing DTH response and induction of Tregs in mice that were deficient in miR-132. In summary, this study demonstrates that TCDD and FICZ have divergent effects on DTH response and T cell differentiation, which is mediated through, at least in part, regulation of miRNA-132 that targets HMGB1.

Identification of hub lncRNA ceRNAs in multiple sclerosis based on ceRNA mechanisms

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system, and the pathogenesis is influenced by genetic susceptibility. Accumulating evidence has demonstrated that long non-coding RNAs (lncRNAs) play essential roles in complex diseases, including acting as competing endogenous RNAs (ceRNAs). However, the functional roles and regulatory mechanisms of lncRNAs acting as ceRNAs in MS are still unclear. In this study, we identified hub lncRNA ceRNAs in MS based on ceRNA mechanisms and annotated their functions. The lncRNA-associated ceRNA network (LACN) was constructed by integrating the expression profiles of lncRNA/mRNA and miRNA in MS and normal samples, and the experimentally validated interactions of lncRNA-miRNA and mRNA-miRNA. We found three hub lncRNA ceRNAs (XIST, OIP5-AS1, and CTB-89H12.4) using the network analysis and obtained 96 lncRNA-mediated competing triplets (LCTs, lncRNA-miRNA-mRNA) with the hub lncRNA ceRNAs, which constituted 3 hub ceRNA modules. The functional analysis identified 12 pathways enriched by the 3 hub lncRNA ceRNAs, of which 6 were confirmed to be related to MS. For example, XIST was enriched in the 'spliceosome' and 'RNA transport' related to the typing of MS, and CTB-89H12.4 was enriched in the 'mTOR signaling pathway,' a potential therapeutic target for MS. We dissected the expression patterns of the 96 LCTs in MS individually. LCT XIST-miR-326-HNRNPA1, for which the expression pattern in MS revealed that XIST and HNRNPA1 were up-regulated and miR-326 was down-regulated, consisted of risk RNAs for MS that were validated by other research. Therefore, XIST-miR-326-HNRNPA1 might play a central role in the pathogenesis of MS. These results will contribute to the discovery of novel biomarkers and the development of new therapeutic methods for MS.

OIP5-AS1 facilitates Th17 differentiation and EAE severity by targeting miR-140-5p to regulate RhoA/ROCK2 signaling pathway

AIMS

Multiple sclerosis (MS) is one of the commonest neurologic disorders globally. LncRNA OIP5-AS1 has been found to be implicated in the etiology of MS. This study was to explore the roles and molecular mechanisms of OIP5-AS1 in the development of MS.

MATERIALS AND METHODS

RT-qPCR assay was used to measure expressions of OIP5-AS1, miR-140-5p, IL-17A mRNA and RhoA mRNA. CD4+IL-17+ cell proportion was determined by flow cytometry. IL-17A secretion was examined by ELISA assay. Cell inflammatory infiltration and demyelination were assessed by histological analyses. The interaction between miR-140-5p and OIP5-AS1 or RhoA 3'UTR was validated by bioinformatical analysis and luciferase reporter assay. Western blot assay was performed to detect protein expressions of ROCK2 and RhoA. An experimental autoimmune encephalomyelitis (EAE) models was established to explore the role of OIP5-AS1 in MS in vivo.

KEY FINDINGS

OIP5-AS1 expression was enhanced in MS patients. Also, elevated OIP5-AS1 level was observed during T-helper 17 (Th17) differentiation. Moreover, OIP5-AS1 promoted Th17 differentiation in vitro and contributed to the development of EAE in vivo. Mechanical explorations revealed that OIP5-AS1 targeted miR-140-5p to regulate Th17 differentiation. Moreover, RhoA was a target of miR-140-5p and miR-140-5p inhibited the activation of RhoA/ROCK2 signaling. Also, RhoA upregulation abrogated the inhibitory effects of miR-140-5p on Th17 differentiation.

SIGNIFICANCE

OIP5-AS1 contributed to EAE development by targeting miR-140-5p/RhoA and activating RhoA/ROCK2 signaling pathway, shedding light on the roles and molecular mechanisms of OIP5-AS1 in the development of MS and providing some candidate targets for the diagnose and treatment of MS.

Administration of Δ9-Tetrahydrocannabinol (THC) Post-Staphylococcal Enterotoxin B Exposure Protects Mice From Acute Respiratory Distress Syndrome and Toxicity

Acute Respiratory Distress Syndrome (ARDS) is a life-threatening complication that can ensue following Staphylococcus aureus infection. The enterotoxin produced by these bacteria (SEB) acts as a superantigen thereby activating a large proportion of T cells leading to cytokine storm and severe lung injury. Δ9Tetrahydrocannabinol (THC), a psychoactive ingredient found in Cannabis sativa, has been shown to act as a potent anti-inflammatory agent. In the current study, we investigated the effect of THC treatment on SEB-induced ARDS in mice. While exposure to SEB resulted in acute mortality, treatment with THC led to 100% survival of mice. THC treatment significantly suppressed the inflammatory cytokines, IFN-γ and TNF-α. Additionally, THC elevated the induction of regulatory T cells (Tregs) and their associated cytokines, IL-10 and TGF-β. Moreover, THC caused induction of Myeloid-Derived Suppressor Cells (MDSCs). THC acted through CB2 receptor as pharmacological inhibitor of CB2 receptors blocked the anti-inflammatory effects. THC-treated mice showed significant alterations in the expression of miRNA (miRs) in the lung-infiltrated mononuclear cells (MNCs). Specifically, THC caused downregulation of let7a-5p which targeted SOCS1 and downregulation of miR-34-5p which caused increased expression of FoxP3, NOS1, and CSF1R. Together, these data suggested that THC-mediated alterations in miR expression in the lungs may play a critical role in the induction of immunosuppressive Tregs and MDSCs as well as suppression of cytokine storm leading to attenuation of SEB-mediated lung injury.

How microRNAs affect the PD-L1 and its synthetic pathway in cancer

Programmed cell death-ligand 1 (PD-L1) is a glycoprotein that is expressed on the cell surface of both hematopoietic and nonhematopoietic cells. PD-L1 play a role in the immune tolerance and protect self-tissues from immune system attack. Dysfunction of this molecule has been highlighted in the pathogenesis of tumors, autoimmunity, and infectious disorders. MicroRNAs (miRNAs) are endogenous molecules that are classified as small non-coding RNA with approximately 20-22 nucleotides (nt) length. The function of miRNAs is based on complementary interactions with target mRNA via matching completely or incompletely. The result of this function is decay of the target mRNA or preventing mRNA translation. In the past decades, several miRNAs have been discovered which play an important role in the regulation of PD-L1 in various malignancies. In this review, we discuss the effect of miRNAs on PD-L1 expression and consider the effect of miRNAs on the synthetic pathway of PD-L1, especially during cancers.

Emerging roles of noncoding RNAs in T cell differentiation and functions in autoimmune diseases

Noncoding RNA comprises of microRNAs (miRNAs) and long noncoding RNAs (lncRNAs) that are abundantly present in mammalian transcriptome. These noncoding RNAs have been implicated in multiple biological processes through the regulation of gene expression. Each of these noncoding RNAs were found to have multiple genes targets. Emerging literature indicated the role of noncoding RNAs in shaping the immune responses which include immune cell development, helper T (Th) cell differentiation as well as maintenance of immune homeostasis by inducing the interplay between effector and regulatory T cells. Dysregulated expression and functions of noncoding RNAs in the immune system leads to aberrations in immune response that lead to the induction of tissue inflammation in autoimmune diseases. In this review, we summarize the current advances of post-transcriptional regulation, focusing on the functions of noncoding RNAs (miRNAs and lncRNAs) during differentiation of Th cells in tissue inflammation in autoimmune diseases.

The protective role of microRNA-140-5p in synovial injury of rats with knee osteoarthritis via inactivating the TLR4/Myd88/NF-κB signaling pathway

Objective: Recently, many studies have revealed the effect of microRNAs (miRNAs) in knee osteoarthritis (KOA). This study aims to explore the role of miR-140-5p in protective effects and mechanisms of synovial injury of rats with KOA via regulating the TLR4/Myd88/NF-κB signaling pathway.

Methods: The models of KOA Wistar rats were established by operation of anterior cruciate ligament transection. Rats were injected with agomir NC or miR-140-5p agomir. MiR-140-5p expression in KOA synovial tissues and synoviocytes was evaluated by reverse transcription quantitative polymerase chain reaction (RT-qPCR). The synoviocytes were transfected with mimics NC sequence and miR-140-5p mimics sequence. The expression of TLR4/Myd88/NF-κB signaling pathway-related proteins was measured by RT-qPCR and western blot analysis. The proliferation and apoptosis of synoviocytes in rats with KOA were evaluated by a string of experiments. The expression levels of inflammatory factors in KOA synovial tissues and synoviocytes were detected.

Results: MiR-140-5p was down-regulated in KOA synovial tissues and synoviocytes. Upregulation of miR-140-5p could inhibit the inflammation reaction and the apoptosis of synoviocytes as well as promote proliferation of synoviocytes of rats with KOA. Furthermore, upregulated miR-140-5p could inactivate the TLR4/Myd88/NF-κB signaling pathway in rats with KOA.

Conclusion: This study suggests that upregulated miR-140-5p could protect synovial injury by restraining inflammation reaction and apoptosis of synoviocytes in KOA rats via TLR4/Myd88/NF-κB signaling pathway inactivation.

The role of gut microbiota in shaping the relapse-remitting and chronic-progressive forms of multiple sclerosis in mouse models

Using a mouse model of multiple sclerosis (MS), experimental autoimmune encephalitis (EAE), we evaluated the role of gut microbiota in modulating chronic-progressive (CP) versus relapse-remitting (RR) forms of the disease. We hypothesized that clinical courses of EAE may be shaped by differential gut microbiota. Metagenomic sequencing of prokaryotic 16S rRNA present in feces from naïve mice and those exhibiting CP-EAE or RR-EAE revealed significantly diverse microbial populations. Microbiota composition was considerably different between naïve strains of mice, suggesting microbial components present in homeostatic conditions may prime mice for divergent courses of disease. Additionally, there were differentially abundant bacteria in CP and RR forms of EAE, indicating a potential role for gut microbiota in shaping tolerant or remittance-favoring, and pathogenic or pro-inflammatory-promoting conditions. Furthermore, immunization to induce EAE led to significant alterations in gut microbiota, some were shared between disease courses and others were course-specific, supporting a role for gut microbial composition in EAE pathogenesis. Moreover, using Linear Discriminant Analysis (LDA) coupled with effect size measurement (LEfSe) to analyze microbial content, biomarkers of each naïve and disease states were identified. Our findings demonstrate for the first time that gut microbiota may determine the susceptibility to CP or RR forms of EAE.

Resveratrol-Mediated Attenuation of Staphylococcus aureus Enterotoxin B-Induced Acute Liver Injury Is Associated With Regulation of microRNA and Induction of Myeloid-Derived Suppressor Cells

Resveratrol (RES) is a polyphenolic compound found abundantly in plant products including red grapes, peanuts, and mulberries. Because of potent anti-inflammatory properties of RES, we investigated whether RES can protect from Staphylococcal enterotoxin B (SEB)-induced acute liver injury in mice. SEB is a potent super antigen that induces robust inflammation and releases inflammatory cytokines that can be fatal. We observed that SEB caused acute liver injury in mice with increases in enzyme aspartate transaminase (AST) levels, and massive infiltration of immune cells into the liver. Treatment with RES (100 mg/kg body weight) attenuated SEB-induced acute liver injury, as indicated by decreased AST levels and cellular infiltration in the liver. Interestingly, RES treatment increased the number of myeloid derived suppressor cells (MDSCs) in the liver. RES treatment led to alterations in the microRNA (miR) profile in liver mononuclear cells (MNCs) of mice exposed to SEB, and pathway analysis indicated these miRs targeted many inflammatory pathways. Of these, we identified miR-185, which was down-regulated by RES, to specifically target Colony Stimulating Factor (CSF1) using transfection studies. Moreover, the levels of CSF1 were significantly increased in RES-treated SEB mice. Because CSF1 is critical in MDSC induction, our studies suggest that RES may induce MDSCs by down-regulating miR-185 leading to increase the expression of CSF1. The data presented demonstrate for the first time that RES can effectively attenuates SEB-induced acute liver injury and that this may result from its action on miRs and induction of MDSCs.

Noncoding RNAs in multiple sclerosis

Multiple sclerosis (MS), a chronic inflammatory demyelinating disease of the central nervous system, is characterized by axonal degeneration and gliosis. Although the causes of MS remain unknown, gene dysregulation in the central nervous system has been associated with the disease pathogenesis. As such, the various regulators of gene expression may be contributing factors. The noncoding (nc) RNAs have piqued the interest of MS researchers due to their known functions in human physiology and various pathological processes, despite being generally characterized as transcripts without apparent protein-coding capacity. Accumulating evidence has indicated that ncRNAs participate in the regulation of MS by acting as epigenetic factors, especially the long (l) ncRNAs and the micro (mi) RNAs, and they are now recognized as key regulatory molecules in MS. In this review, we summarize the most current studies on the contribution of ncRNAs in MS pathogenic processes and discuss their potential applications in the diagnosis and treatment of MS.

miR-15a-5p suppresses inflammation and fibrosis of peritoneal mesothelial cells induced by peritoneal dialysis via targeting VEGFA

Long-term peritoneal dialysis (PD) often ends up with ultrafiltration failure (UFF) which is partially caused by persistent inflammation and fibrosis of peritoneal tissues. However, the mechanism is still unclear. In the current study, the peritoneum from UFF patients demonstrated inflammation and fibrosis which were positively related to the expression of vascular endothelial growth factor A (VEGFA). The in vitro model using human peritoneal mesothelial cells (HPMCs) stimulated by high glucose or advanced glycation end (AGE) product showed consistent changes of inflammation, fibrosis, and VEGFA. What's more, we showed that VEGFA was an instigator of inflammation and fibrosis. Several microRNAs (miRNAs) have been reported to regulate expression of VEGFA elsewhere. Five of them were selected to test the expression in the peritoneum of patients with PD. Results suggested that miR-15a-5p was the most significantly downregulated one. Also, in high glucose or AGE product-stimulated HPMCs, miR-15a-5p decreased. When miRNA mimic was used to restore the expression of miR-15a-5p, high glucose-induced VEGFA was repressed. The predicted binding site between these two molecules was confirmed by the dual-luciferase assay. Restoration of miR-15a-5p restrained inflammation and fibrosis of HPMCs. TGF-β1/Smad2 was shown to be the downstream signaling pathway and their activity was regulated by miR-15a-5p/VEGFA. In conclusion, our current study demonstrates that miR-15a-5p acts as a regulator of VEGFA mRNA and the following inflammation and fibrosis in peritoneal mesothelial cells. The miR-15a-5p/VEGFA pathway may be a potential target for preventing ultrafiltration failure in patients with PD.

MicroRNA-30 modulates metabolic inflammation by regulating Notch signaling in adipose tissue macrophages

Background/Objectives

Obesity is a pandemic disorder that is characterized by accumulation of adipose tissue and chronic-low grade inflammation that is driven primarily by adipose tissue macrophages (ATMs). While ATM polarization from pro-(M1)to anti-(M2) inflammatory phenotype influences insulin sensitivity and energy expenditure, the mechanisms of such a switch are unclear. In the current study we identified epigenetic pathways including microRNAs (miR) in ATMs that regulate obesity-induced inflammation.

Subjects/Methods

Male C57BL/6J mice were fed normal chow diet (NCD) or high-fat diet (HFD) for 16 weeks to develop lean and diet-induced obese mice respectively. Transcriptome microarrays, microRNA microarrays, and meDIP-Seq were performed on ATMs isolated from visceral fat. Pathway analysis and bone marrow derived macrophage (BMDM) transfections further allowed computational and functional analysis of miRNA-mediated ATM polarization.

Results

ATMs from HFD-fed mice were skewed towards M1 inflammatory phenotype. Concurrently, the expression of miRs 30a-5p, 30c-5p, and 30e-5p was downregulated in ATMs from HFD mice when compared to mice fed NCD. The miR-30 family was shown to target Delta-like-4, a Notch1 ligand, whose expression was increased in HFD ATMs. Inhibition of miR-30 in conditioned BMDM triggered Notch1 signaling, pro-inflammatory cytokine production, and M1 macrophage polarization. In addition, DNA hypermethylation was observed in mir30-associated CpG islands suggesting HFD downregulates miR-30 through epigenetic modifications.

Conclusions

HFD-induced obesity downregulates miR-30 by DNA methylation thereby inducing Notch1 signaling in ATMs and their polarization to M1 macrophages. These findings identify miR-30 as a regulator of pro-inflammatory ATM polarization and suggest miR-30 manipulation could be a therapeutic target for obesity-induced inflammation.

Control of T cell effector functions by miRNAs

The differentiation of effector T cells is a tightly regulated process that relies on the selective expression of lineage-defining master regulators that orchestrate unique transcriptional programs, including the production of distinct sets of effector cytokines. miRNAs are post-transcriptional regulators that are now viewed as critical players in these gene expression networks and help defining cell identity and function. This review summarises the role of individual miRNAs in the regulation of the differentiation of effector T cell subsets, including CD4⁺ T helper cells, cytotoxic CD8⁺ T cells and innate-like NKT cells. Moreover, we refer to miRNAs that have been identified to affect simultaneously two or more effector T cell populations, impacting on the balance between effector T cells in vivo, thus constituting potential biomarkers or targets for therapies aiming at boosting immunity or controlling autoimmunity.

Identifying characteristic miRNAs-genes and risk pathways of multiple sclerosis based on bioinformatics analysis

Multiple sclerosis is a chronic autoimmune disorder of the central nervous system. In MS, the genetic susceptibility is high and currently there is no effective treatment. MicroRNA, a small non-coding RNA, plays a vital role in immune responses. Aberrant or dysfunctional miRNAs may cause several diseases, including MS, thus miRNAs and miRNA related genes may be therapeutic weapons against MS. Here, we identified 21 miRNAs in peripheral blood mono-nuclear cells from over 600 persons, including healthy controls. By using informatics databases, 1637 susceptibility genes were evaluated and Cytoscape was used to integrate and visualize the relation between the miRNA identified and susceptibility genes. By using the cluster Profile package, a total of 10 risk pathways were discovered. Top pathways included: hsa05200 (pathway in cancer), hsa04010 (MAPK signaling pathway), and hsa04060 (cytokine-cytokine receptor interaction). By using the STRING database, a protein-protein interaction network was conducted to identify highly susceptibility genes. Moreover, the GSE21942 dataset was used to indicate the gene expression profiles and to correct prediction results, thereby identifying the most pivotal genes. The MiRSystem database provided information on both pivotal miRNAs and genes. In conclusion, miR-199a and miR-142-3p may be crucial for MS by targeting pivotal susceptibility genes, in particular KRAS and IL7R.

Physical rehabilitation modulates microRNAs involved in multiple sclerosis: a case report

This study shows that neuromuscular taping improves gait, balance, pain and ability to walk and conduct daily activities in a multiple sclerosis patient. It is the first study to identify a panel of miRNAs modulated throughout rehabilitation using neuromuscular taping in a multiple sclerosis patient.

The role of microRNAs in the pathogenesis of autoimmune diseases

MicroRNAs (miRNAs) are single-stranded, endogenous non-coding small RNAs, ranging from 18 to 25 nucleotides in length. Growing evidence suggests that miRNAs are essential in regulating gene expression, cell development, differentiation and function. Autoimmune diseases are a family of chronic systemic inflammatory diseases. Recent findings on miRNA expression profiles have been suggesting their role as biomarkers in autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis and Sjögren's syndrome. In this review, we summarize the characteristics of miRNAs and their functional role in the immune system and autoimmune diseases including systemic lupus erythematosus, primary Sjögren's syndrome, rheumatoid arthritis, systemic sclerosis, multiple sclerosis and psoriasis; moreover, we depict the advantages of miRNAs in modern diagnostics.