Dysregulated Network of miRNAs Involved in the Pathogenesis of Multiple Sclerosis

Altered gene expression of miR-155 in peripheral blood mononuclear cells of Multiple sclerosis patients: Correlation with TH17 frequency, inflammatory cytokine profile and autoimmunity

In the chronic, organ-specific autoimmune disorder known as multiple sclerosis (MS), the myelin sheath is attacked by immune cells, leading to damage to the central nervous system (CNS). It has been discovered that miRNAs are important in the etiology of MS, since deregulation of miRNAs can lead to defects in immune tolerance. In this study, we sought to investigate the involvement of miR-155 in MS disorder through examination of its altered expression in peripheral blood mononuclear cells (PBMCs) of patients with MS in compare with healthy controls. Furthermore, we investigated the frequency of T helper 17 cells (Th17) in MS patients and analyzed not only the expression of inflammatory cytokines including IL-6, IL-17 and IL-21 in patients' PBMCs, but also their secreted levels in serum of patients suffering from MS. Subsequently, we assessed the correlation between miR-155 expression with Th17 frequency and levels of released cytokines in serum. Upregulated expression of miR-155 was detected in PBMCs of MS patients and the positive correlation between its expression with increased frequency of Th17 cells and their related inflammatory cytokine profile augmented secretion in serum were identified. In conclusion, our study revealed the significant association between Th17 frequency, increased level of cytokines related to Th17 differentiation and function with miR-155 augmented expression in PBMCs. So, our findings suggested that miR-155 and especially its expression in immune cells including effector T cells can be the target of future therapeutic strategies for the management and prevention of MS progression, however, further research is requisite before this approach can be utilized in clinical practice.

Exploring the versatility of miRNA-128: a comprehensive review on its role as a biomarker and therapeutic target in clinical pathways

MicroRNAs (miRNAs/ miRs) are short, noncoding RNAs, usually consisting of 18 to 24 nucleotides, that control gene expression after the process of transcription and have crucial roles in several clinical processes. This article seeks to provide an in-depth review and evaluation of the many activities of miR-128, accentuating its potential as a versatile biomarker and target for therapy; The circulating miR-128 has garnered interest because of its substantial influence on gene regulation and its simplicity in extraction. Several miRNAs, such as miR-128, have been extracted from circulating blood cells, cerebrospinal fluid, and plasma/serum. The miR-128 molecule can specifically target a diverse range of genes, enabling it to have intricate physiological impacts by concurrently regulating many interrelated pathways. It has a vital function in several biological processes, such as modulating the immune system, regulating brain plasticity, organizing the cytoskeleton, and inducing neuronal death. In addition, miR-128 modulates genes associated with cell proliferation, the cell cycle, apoptosis, plasma LDL levels, and gene expression regulation in cardiac development. The dysregulation of miR-128 expression and activity is associated with the development of immunological responses, changes in neural plasticity, programmed cell death, cholesterol metabolism, and heightened vulnerability to autoimmune illnesses, neuroimmune disorders, cancer, and cardiac problems; The paper highlights the importance of studying the consequences of miR-128 dysregulation in these specific locations. By examining the implications of miRNA-128 dysregulation in these areas, the article underscores its significance in diagnosis and treatment, providing a foundation for research and clinical applications.

Epstein-Barr virus-encoded BART9 and BART15 miRNAs are elevated in exosomes of cerebrospinal fluid from relapsing-remitting multiple sclerosis patients

Epstein-Barr virus (EBV) infection is approved as the main environmental trigger of multiple sclerosis (MS). In this path, we quantified ebv-miR-BART9-3p and ebv-miR-BART15 in exosomes of cerebrospinal fluid (CSF) of untreated relapsing-remitting MS (RRMS) patients in comparison with the control group. Interestingly, patients displayed significant upregulation of ebv-miR-BART9-3p (18.4-fold) and ebv-miR-BART15 (3.1-fold) expression in CSF exosomes. Moreover, the expression levels of hsa-miR-21-5p and hsa-miR-146a-5p were found to be significantly elevated in the CSF samples obtained from the patient group compared to those obtained from the HC group. The levels of Interferon-gamma (IFN-γ), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-17 (IL-17), interleukin-23 (IL-23), transforming growth factor beta (TGF-β), and tumor necrosis factor-alpha (TNF-α) were observed to be significantly elevated in the serum and CSF exosomes of the patients. The highest increase was observed in TGF-β (8.5-fold), followed by IL-23 (3.9-fold) in CSF exosomes. These findings are in agreement with the association between EBV infection and inflammatory cytokines induction. Furthermore, the ratios of TGF-β: TNF-α and TGF-β: IFN-γ attained values of 4 to 16.4 and 1.3 to 3.6, respectively, in the CSF exosomes of the patients, in comparison to those of the control group. These findings show EBV activity in RRMS patients is different from that of healthy ones. Elevation of ebv-miR-BART9-3p, ebv-miR-BART15, and inflammatory cytokines expression in CSF exosomes in RRMS patients provides a substantial link between EBV activity and the onset of the disease, as well as the transition from EBV infection to MS.

Mechanisms of microRNA-132 in central neurodegenerative diseases: A comprehensive review

MicroRNA-132 (miR-132) is a highly conserved molecule that plays a crucial regulatory role in central nervous system (CNS) disorders. The expression levels of miR-132 exhibit variability in various neurological disorders and have been closely linked to disease onset and progression. The expression level of miR-132 in the CNS is regulated by a diverse range of stimuli and signaling pathways, including neuronal migration and integration, dendritic outgrowth, and complexity, synaptogenesis, synaptic plasticity, as well as inflammation and apoptosis activation. The aberrant expression of miR-132 in various central neurodegenerative diseases has garnered widespread attention. Clinical studies have revealed altered miR-132 expression levels in both chronic and acute CNS diseases, positioning miR-132 as a potential biomarker or therapeutic target. An in-depth exploration of miR-132 holds the promise of enhancing our understanding of the mechanisms underlying CNS diseases, thereby offering novel insights and strategies for disease diagnosis and treatment. It is anticipated that this review will assist researchers in recognizing the potential value of miR-132 and in generating innovative ideas for clinical trials related to CNS degenerative diseases.

Exploring the theranostic potentials of miRNA and epigenetic networks in autoimmune diseases: A comprehensive review

BACKGROUND

Autoimmune diseases (AD) are severe pathophysiological ailments that are stimulated by an exaggerated immunogenic response towards self-antigens, which can cause systemic or site-specific organ damage. An array of complex genetic and epigenetic facets majorly contributes to the progression of AD, thus providing significant insight into the regulatory mechanism of microRNA (miRNA). miRNAs are short, non-coding RNAs that have been identified as essential contributors to the post-transcriptional regulation of host genome expression and as crucial regulators of a myriad of biological processes such as immune homeostasis, T helper cell differentiation, central and peripheral tolerance, and immune cell development.

AIMS

This article tends to deliberate and conceptualize the brief pathogenesis and pertinent epigenetic regulatory mechanism as well as miRNA networks majorly affecting five different ADs namely rheumatoid arthritis (RA), type 1 diabetes, multiple sclerosis (MS), systemic lupus erythematosus (SLE) and inflammatory bowel disorder (IBD) thereby providing novel miRNA-based theranostic interventions.

RESULTS & DISCUSSION

Pertaining to the differential expression of miRNA attributed in target tissues and cellular bodies of innate and adaptive immunity, a paradigm of scientific expeditions suggests an optimistic correlation between immunogenic dysfunction and miRNA alterations.

CONCLUSION

Therefore, it is not astonishing that dysregulations in miRNA expression patterns are now recognized in a wide spectrum of disorders, establishing themselves as potential biomarkers and therapeutic targets. Owing to its theranostic potencies, miRNA targets have been widely utilized in the development of biosensors and other therapeutic molecules originating from the same.

miRNAs: Targets to Investigate Herpesvirus Infection Associated with Neurological Disorders

Herpesvirus is associated with various neurological disorders and a specific diagnosis is associated with a better prognosis. MicroRNAs (miRNAs) are potential diagnostic and prognostic biomarkers of neurological diseases triggered by herpetic infection. In this review, we discuss miRNAs that have been associated with neurological disorders related to the action of herpesviruses. Human miRNAs and herpesvirus-encoded miRNAs were listed and discussed. This review article will be valuable in stimulating the search for new diagnostic and prognosis alternatives and understanding the role of these miRNAs in neurological diseases triggered by herpesviruses.

The fluctuations of expression profiles of critical genes in the miRNA maturation process and pro-and anti-inflammatory cytokines in the pathogenesis and progression of multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a central nervous system disease known for immune-mediated demyelination, inflammatory, and neurodegeneration symptoms. Discovering molecular biomarkers to classify RRMS and SPMS patients, monitor the disease activity, and response to particular treatments is one area that has received notable attraction. MicroRNA (miRNA), a single-stranded non-coding RNA molecule, is a significant regulator of gene expression recruited in pathogenic mechanisms in diverse diseases, especially cancer and MS. Also, the relapsing-remitting features of MS exhibit that both inflammatory and anti-inflammatory cytokines are effective in the progression of the disease over time.

METHODS AND RESULTS

It was assessed the expression patterns of the genes (Drosha, Pasha (DGCR8), and Dicer ) encoding the critical enzymes in the processing steps of miRNA maturation and major pro-inflammatory and anti-inflammatory cytokines (IFN-α, IFN-β, and IL-6) in blood cells of 40 MS patients (two groups of 10 men and women in both clinical courses of RR and SPMS patients) in comparison with 20 healthy control group (10 males and 10 females). The highest transcription activity of Drosha was observed for RRMS patients (4.2 and 3.6-fold, respectively), and the expression ratio was down regulated in male and female patients with SPMS (3.9- and 3.1-fold, respectively). Considering the studied cytokines, the increase in expression ratio of IL-6 in SPMS patients and the decrease in transcript abundance of INF-α, and INF-β cytokines are consistent with the progression of the disease.

CONCLUSIONS

Our findings showed that the high and low transcriptional levels of the considered genes seem to be effective in the pathogenesis and progression of MS.

The role of miRNAs in multiple sclerosis pathogenesis, diagnosis, and therapeutic resistance

In recent years, microRNAs (miRNAs) have gained increased attention from researchers around the globe. Although it is twenty nucleotides long, it can modulate several gene targets simultaneously. Their mal expression is a signature of various pathologies, and they provide the foundation to elucidate the molecular mechanisms of each pathology. Among the debilitating central nervous system (CNS) disorders with a growing prevalence globally is the multiple sclerosis (MS). Moreover, the diagnosis of MS is challenging due to the lack of disease-specific biomarkers, and the diagnosis mainly depends on ruling out other disabilities. MS could adversely affect patients' lives through its progression, and only symptomatic treatments are available as therapeutic options, but an exact cure is yet unavailable. Consequently, this review hopes to further the study of the biological features of miRNAs in MS and explore their potential as a therapeutic target.

The Application of MicroRNAs in Glaucoma Research: A Bibliometric and Visualized Analysis

Glaucoma is similar to a neurodegenerative disorder and leads to global irreversible loss of vision. Despite extensive research, the pathophysiological mechanisms of glaucoma remain unclear, and no complete cure has yet been identified for glaucoma. Recent studies have shown that microRNAs can serve as diagnostic biomarkers or therapeutic targets for glaucoma; however, there are few bibliometric studies that focus on using microRNAs in glaucoma research. Here, we have adopted a bibliometric analysis in the field of microRNAs in glaucoma research to manifest the current tendencies and research hotspots and to present a visual map of the past and emerging tendencies in this field. In this study, we retrieved publications in the Web of Science database that centered on this field between 2007 and 2022. Next, we used VOSviewer, CiteSpace, Scimago Graphica, and Microsoft Excel to present visual representations of a co-occurrence analysis, co-citation analysis, tendencies, hotspots, and the contributions of authors, institutions, journals, and countries/regions. The United States was the main contributor. Investigative Ophthalmology and Visual Science has published the most articles in this field. Over the past 15 years, there has been exponential growth in the number of publications and citations in this field across various countries, organizations, and authors. Thus, this study illustrates the current trends, hotspots, and emerging frontiers and provides new insight and guidance for searching for new diagnostic biomarkers and clinical trials for glaucoma in the future. Furthermore, international collaborations can also be used to broaden and deepen the field of microRNAs in glaucoma research.

Multiplex Analysis of Cerebrospinal Fluid and Serum Exosomes MicroRNAs of Untreated Relapsing Remitting Multiple Sclerosis (RRMS) and Proposing Noninvasive Diagnostic Biomarkers

Exosomal microRNAs (miRNAs) are emerging diagnostic biomarkers for neurodegenerative diseases. In this study, we aimed to detect relapsing-remitting multiple sclerosis (RRMS)-specific miRNAs in cerebrospinal fluid (CSF) and serum exosomes with diagnostic potential. One ml of CSF and serum sample were collected from each of the 30 untreated RRMS patients and healthy controls (HCs). A panel of 18 miRNAs affecting inflammatory responses was applied, and qRT-PCR was conducted to detect differentially expressed exosomal miRNAs in CSF and serum of RRMS patients. We identified that 17 out of 18 miRNAs displayed different patterns in RRMS patients compared to HCs. Let-7 g-5p, miR-18a-5p, miR-145-5p, and miR-374a-5p with dual pro-inflammatory and anti-inflammatory actions and miR-150-5p and miR-342-3p with anti-inflammatory action were significantly upregulated in both CSF and serum-derived exosomes of RRMS patients compared to corresponding HCs. Additionally, anti-inflammatory miR-132-5p and pro-inflammatory miR-320a-5p were significantly downregulated in both CSF and serum-derived exosomes of RRMS patients compared to HCs. Ten of 18 miRNAs were differentially expressed in CSF and serum exosomes of the patients. Furthermore, miR-15a-5p, miR-19b-3p, and miR-432-5p were upregulated, and miR-17-5p was downregulated only in CSF exosomes. Interestingly, U6 housekeeping gene was differentially expressed in CSF and serum exosomes, in both RRMS and HCs. As the first report describing CSF exosomal miRNAs expression profile compared to that of serum exosomes in untreated RRMS patients, we showed that CSF and serum exosomes are not identical in terms of biological compounds and display different patterns in miRNAs and U6 expression.

Exploring the impact of miR-128 in inflammatory diseases: A comprehensive study on autoimmune diseases

microRNAs (miRNAs) play a crucial role in various biological processes, including immune system regulation, such as cell proliferation, tolerance (central and peripheral), and T helper cell development. Dysregulation of miRNA expression and activity can disrupt immune responses and increase susceptibility to neuroimmune disorders. Conversely, miRNAs have been shown to have a protective role in modulating immune responses and preventing autoimmunity. Specifically, reducing the expression of miRNA-128 (miR-128) in an Alzheimer's disease (AD) mouse model has been found to improve cognitive deficits and reduce neuropathology. This comprehensive review focuses on the significance of miR-128 in the pathogenesis of neuroautoimmune disorders, including multiple sclerosis (MS), AD, Parkinson's disease (PD), Huntington's disease (HD), epilepsy, as well as other immune-mediated diseases such as inflammatory bowel disease (IBD) and rheumatoid arthritis (RA). Additionally, we present compelling evidence supporting the potential use of miR-128 as a diagnostic or therapeutic biomarker for neuroimmune disorders. Collectively, the available literature suggests that targeting miR-128 could be a promising strategy to alleviate the behavioral symptoms associated with neuroimmune diseases. Furthermore, further research in this area may uncover new insights into the molecular mechanisms underlying these disorders and potentially lead to the development of novel therapeutic approaches.

Remyelination in multiple sclerosis from the miRNA perspective

Remyelination relies on the repair of damaged myelin sheaths, involving microglia cells, oligodendrocyte precursor cells (OPCs), and mature oligodendrocytes. This process drives the pathophysiology of autoimmune chronic disease of the central nervous system (CNS), multiple sclerosis (MS), leading to nerve cell damage and progressive neurodegeneration. Stimulating the reconstruction of damaged myelin sheaths is one of the goals in terms of delaying the progression of MS symptoms and preventing neuronal damage. Short, noncoding RNA molecules, microRNAs (miRNAs), responsible for regulating gene expression, are believed to play a crucial role in the remyelination process. For example, studies showed that miR-223 promotes efficient activation and phagocytosis of myelin debris by microglia, which is necessary for the initiation of remyelination. Meanwhile, miR-124 promotes the return of activated microglia to the quiescent state, while miR-204 and miR-219 promote the differentiation of mature oligodendrocytes. Furthermore, miR-138, miR-145, and miR-338 have been shown to be involved in the synthesis and assembly of myelin proteins. Various delivery systems, including extracellular vesicles, hold promise as an efficient and non-invasive way for providing miRNAs to stimulate remyelination. This article summarizes the biology of remyelination as well as current challenges and strategies for miRNA molecules in potential diagnostic and therapeutic applications.

MicroRNAs in tear fluids predict underlying molecular changes associated with Alzheimer's disease

Extracellular circulating microRNAs (miRNAs) have been discussed as potential biomarkers for Alzheimer's disease (AD) diagnosis. As the retina is a part of the CNS, we hypothesize that miRNAs expression levels in the brain, particularly neocortex-hippocampus, eye tissues, and tear fluids are similar at different stages of AD progression. Ten miRNA candidates were systematically investigated in transgenic APP-PS1 mice, noncarrier siblings, and C57BL/6J wild-type controls at young and old ages. Relative expression levels of tested miRNAs revealed a similar pattern in both APP-PS1 mice and noncarrier siblings when compared with age- and sex-matched wild-type controls. However, the differences seen in expression levels between APP-PS1 mice and noncarrier siblings could possibly have resulted from underlying molecular etiology of AD. Importantly, miRNAs associated with amyloid beta (Aβ) production (-101a, -15a, and -342) and proinflammation (-125b, -146a, and -34a) showed significant up-regulations in the tear fluids with disease progression, as tracked by cortical Aβ load and reactive astrogliosis. Overall, for the first time, the translational potential of up-regulated tear fluid miRNAs associated with AD pathogenesis was comprehensively demonstrated.

Insight into Early Diagnosis of Multiple Sclerosis by Targeting Prognostic Biomarkers

Multiple sclerosis (MS) is a central nervous system (CNS) immune-mediated disease that mainly strikes young adults and leaves them disabled. MS is an autoimmune illness that causes the immune system to attack the brain and spinal cord. The myelin sheaths, which insulate the nerve fibers, are harmed by our own immune cells, and this interferes with brain signal transmission. Numbness, tingling, mood swings, memory problems, exhaustion, agony, vision problems, and/or paralysis are just a few of the symptoms. Despite technological advancements and significant research efforts in recent years, diagnosing MS can still be difficult. Each patient's MS is distinct due to a heterogeneous and complex pathophysiology with diverse types of disease courses. There is a pressing need to identify markers that will allow for more rapid and accurate diagnosis and prognosis assessments to choose the best course of treatment for each MS patient. The cerebrospinal fluid (CSF) is an excellent source of particular indicators associated with MS pathology. CSF contains molecules that represent pathological processes such as inflammation, cellular damage, and loss of blood-brain barrier integrity. Oligoclonal bands, neurofilaments, MS-specific miRNA, lncRNA, IgG-index, and anti-aquaporin 4 antibodies are all clinically utilised indicators for CSF in MS diagnosis. In recent years, a slew of new possible biomarkers have been presented. In this review, we look at what we know about CSF molecular markers and how they can aid in the diagnosis and differentiation of different MS forms and treatment options, and monitoring and predicting disease progression, therapy response, and consequences during such opportunistic infections.

Newly Identified Deficiencies in the Multiple Sclerosis Central Nervous System and Their Impact on the Remyelination Failure

The pathogenesis of multiple sclerosis (MS) remains enigmatic and controversial. Myelin sheaths in the central nervous system (CNS) insulate axons and allow saltatory nerve conduction. MS brings about the destruction of myelin sheaths and the myelin-producing oligodendrocytes (ODCs). The conundrum of remyelination failure is, therefore, crucial in MS. In this review, the roles of epidermal growth factor (EGF), normal prions, and cobalamin in CNS myelinogenesis are briefly summarized. Thereafter, some findings of other authors and ourselves on MS and MS-like models are recapitulated, because they have shown that: (a) EGF is significantly decreased in the CNS of living or deceased MS patients; (b) its repeated administration to mice in various MS-models prevents demyelination and inflammatory reaction; (c) as was the case for EGF, normal prion levels are decreased in the MS CNS, with a strong correspondence between liquid and tissue levels; and (d) MS cobalamin levels are increased in the cerebrospinal fluid, but decreased in the spinal cord. In fact, no remyelination can occur in MS if these molecules (essential for any form of CNS myelination) are lacking. Lastly, other non-immunological MS abnormalities are reviewed. Together, these results have led to a critical reassessment of MS pathogenesis, partly because EGF has little or no role in immunology.

Emerging Biomarkers of Multiple Sclerosis in the Blood and the CSF: A Focus on Neurofilaments and Therapeutic Considerations

INTRODUCTION

Multiple Sclerosis (MS) is the most common immune-mediated chronic neurodegenerative disease of the central nervous system (CNS) affecting young people. This is due to the permanent disability, cognitive impairment, and the enormous detrimental impact MS can exert on a patient's health-related quality of life. It is of great importance to recognise it in time and commence adequate treatment at an early stage. The currently used disease-modifying therapies (DMT) aim to reduce disease activity and thus halt disability development, which in current clinical practice are monitored by clinical and imaging parameters but not by biomarkers found in blood and/or the cerebrospinal fluid (CSF). Both clinical and radiological measures routinely used to monitor disease activity lack information on the fundamental pathophysiological features and mechanisms of MS. Furthermore, they lag behind the disease process itself. By the time a clinical relapse becomes evident or a new lesion appears on the MRI scan, potentially irreversible damage has already occurred in the CNS. In recent years, several biomarkers that previously have been linked to other neurological and immunological diseases have received increased attention in MS. Additionally, other novel, potential biomarkers with prognostic and diagnostic properties have been detected in the CSF and blood of MS patients.

AREAS COVERED

In this review, we summarise the most up-to-date knowledge and research conducted on the already known and most promising new biomarker candidates found in the CSF and blood of MS patients.

DISCUSSION

the current diagnostic criteria of MS relies on three pillars: MRI imaging, clinical events, and the presence of oligoclonal bands in the CSF (which was reinstated into the diagnostic criteria by the most recent revision). Even though the most recent McDonald criteria made the diagnosis of MS faster than the prior iteration, it is still not an infallible diagnostic toolset, especially at the very early stage of the clinically isolated syndrome. Together with the gold standard MRI and clinical measures, ancillary blood and CSF biomarkers may not just improve diagnostic accuracy and speed but very well may become agents to monitor therapeutic efficacy and make even more personalised treatment in MS a reality in the near future. The major disadvantage of these biomarkers in the past has been the need to obtain CSF to measure them. However, the recent advances in extremely sensitive immunoassays made their measurement possible from peripheral blood even when present only in minuscule concentrations. This should mark the beginning of a new biomarker research and utilisation era in MS.

Extracellular Vesicles, Stem Cells and the Role of miRNAs in Neurodegeneration

There are different modalities of intercellular communication governed by cellular homeostasis. In this review, we will explore one of these forms of communication called extracellular vesicles (EVs). These vesicles are released by all cells in the body and are heterogeneous in nature. The primary function of EVs is to share information through their cargo consisting of proteins, lipids and nucleic acids (mRNA, miRNA, dsDNA etc.) with other cells, which have a direct consequence on their microenvironment. We will focus on the role of EVs of mesenchymal stem cells (MSCs) in the nervous system and how these participate in intercellular communication to maintain physiological function and provide neuroprotection. However, deregulation of this same communication system could play a role in several neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, Amyotrophic lateral sclerosis, multiple sclerosis, prion disease and Huntington's disease. The release of EVs from a cell provides crucial information to what is happening inside the cell and thus could be used in diagnostics and therapy. We will discuss and explore new avenues for the clinical applications of using engineered MSC-EVs and their potential therapeutic benefit in treating neurodegenerative diseases.

The circular RNA circINPP4B acts as a sponge of miR-30a to regulate Th17 cell differentiation during progression of experimental autoimmune encephalomyelitis

Circular RNAs (circRNAs) regulate gene expression and participate in various biological and pathological processes. However, little is known about the effects of specific circRNAs on T helper cell 17 (Th17) differentiation and related autoimmune diseases, such as multiple sclerosis (MS). Here, using transcriptome microarray analysis at different stages of experimental autoimmune encephalomyelitis (EAE), we identified the EAE progression-related circINPP4B, which showed upregulated expression in Th17 cells from mice with EAE and during Th17 differentiation in vitro. Silencing of circINPP4B inhibited Th17 differentiation and alleviated EAE, characterized by less demyelination and Th17 infiltration in the spinal cord. Mechanistically, circINPP4B served as a sponge that directly targeted miR-30a to regulate Th17 differentiation. Furthermore, circINPP4B levels were associated with the developing phases of clinical relapsing-remitting MS patients. Our results indicate that circINPP4B plays an important role in promoting Th17 differentiation and progression of EAE by targeting miR-30a, which provides a potential diagnostic and therapeutic target for Th17-mediated MS.

MicroRNAs, Multiple Sclerosis, and Depression

Multiple sclerosis (MS) is a chronic disease of the central nervous system that affects the brain and spinal cord. There are several disease courses in MS including relapsing–remitting MS (RRMS), primary progressive MS (PPMS), and secondary progressive MS (SPMS). Up to 50% of MS patients experience depressive disorders. Major depression (MD) is a serious comorbidity of MS. Many dysfunctions including neuroinflammation, peripheral inflammation, gut dysbiosis, chronic oxidative and nitrosative stress, and neuroendocrine and mitochondrial abnormalities may contribute to the comorbidity between MS and MD. In addition to these actions, medical treatment and microRNA (miRNA) regulation may also be involved in the mechanisms of the comorbidity between MS and MD. In the study, I review many common miRNA biomarkers for both diseases. These common miRNA biomarkers may help further explore the association between MS and MD.

Altered expression of microRNAs and B lymphocytes during Natalizumab therapy in multiple sclerosis

MicroRNAs (miRNAs) are a family of non-translated small ribonucleic acids (RNAs) measuring 21–25 nucleotides in length that play various roles in multiple sclerosis (MS). By regulating gene expression via either mediating translational repression or cleavage of the target RNA, miRNAs can alter the expression of transcripts in different cells, such as B lymphocytes, also known as B cells. They are crucial in the pathogenesis of MS; however, they have not been extensively studied during the treatment of some drugs such as natalizumab (NTZ). NTZ is a humanized immunoglobulin G4 antibody antagonist for integrin alpha 4 (α4) used in the treatment of MS. The drug reduces the homing of lymphocytes to inflammation sites. Integrin α4 expression on the cell surface of B cells is related to MS severity, indicating a critical component in the pathogenesis of the disease. NTZ plays an important role in modifying the gene expression in B cells and the levels of miRNAs in the treatment of MS. In this review, we have described changes in gene expression in B cells and the levels of miRNAs during NTZ therapy in MS and its relapse. Studies using the experimental autoimmune encephalomyelitis (EAE) model and those involving patients with MS have described changes in the levels of microRNAs in the regulation of proteins affected by specific miRNAs, gene expression in B cells, and certain functions of B cells as well as their subpopulations. Therefore, there is a possibility that some miRNAs could be studied at different stages of MS during NTZ treatment, and these specific miRNAs can be tested as markers of therapeutic response to this drug in future studies. Physiopathology, gene expression in B cells and their subpopulations can help understand this complex puzzle involving miRNAs and the therapeutic response of patients with MS.

miRNAs in Microglia: Important Players in Multiple Sclerosis Pathology

Microglia are the resident immune cells of the central nervous system and important regulators of brain homeostasis. Central to this role is a dynamic phenotypic plasticity that enables microglia to respond to environmental and pathological stimuli. Importantly, different microglial phenotypes can be both beneficial and detrimental to central nervous system health. Chronically activated inflammatory microglia are a hallmark of neurodegeneration, including the autoimmune disease multiple sclerosis (MS). By contrast, microglial phagocytosis of myelin debris is essential for resolving inflammation and promoting remyelination. As such, microglia are being explored as a potential therapeutic target for MS. MicroRNAs (miRNAs) are short non-coding ribonucleic acids that regulate gene expression and act as master regulators of cellular phenotype and function. Dysregulation of certain miRNAs can aberrantly activate and promote specific polarisation states in microglia to modulate their activity in inflammation and neurodegeneration. In addition, miRNA dysregulation is implicated in MS pathogenesis, with circulating biomarkers and lesion specific miRNAs identified as regulators of inflammation and myelination. However, the role of miRNAs in microglia that specifically contribute to MS progression are still largely unknown. miRNAs are being explored as therapeutic agents, providing an opportunity to modulate microglial function in neurodegenerative diseases such as MS. This review will focus firstly on elucidating the complex role of microglia in MS pathogenesis. Secondly, we explore the essential roles of miRNAs in microglial function. Finally, we focus on miRNAs that are implicated in microglial processes that contribute directly to MS pathology, prioritising targets that could inform novel therapeutic approaches to MS.

The Role of Extracellular Vesicles in Demyelination of the Central Nervous System

It is being increasingly demonstrated that extracellular vesicles (EVs) are deeply involved in the physiology of the central nervous system (CNS). Processes such as synaptic activity, neuron-glia communication, myelination and immune response are modulated by EVs. Likewise, these vesicles may participate in many pathological processes, both as triggers of disease or, on the contrary, as mechanisms of repair. EVs play relevant roles in neurodegenerative disorders such as Alzheimer’s or Parkinson’s diseases, in viral infections of the CNS and in demyelinating pathologies such as multiple sclerosis (MS). This review describes the involvement of these membrane vesicles in major demyelinating diseases, including MS, neuromyelitis optica, progressive multifocal leukoencephalopathy and demyelination associated to herpesviruses.

Whole-Transcriptome Analysis in Peripheral Blood Mononuclear Cells from Patients with Lipid-Specific Oligoclonal IgM Band Characterization Reveals Two Circular RNAs and Two Linear RNAs as Biomarkers of Highly Active Disease

The presence of anti-myelin lipid-specific oligoclonal IgM bands (LS-OCMBs) has been defined as an accurate predictor of an aggressive evolution of multiple sclerosis. However, the detection of this biomarker is performed in cerebrospinal fluid, a quite invasive liquid biopsy. In the present study we aimed at studying the expression profile of miRNA, snoRNA, circRNA and linearRNA in peripheral blood mononuclear cells (PBMCs) from patients with lipid-specific oligoclonal IgM band characterization. We included a total of 89 MS patients, 47 with negative LS-OCMB status and 42 with positive status. Microarray (miRNA and snoRNA) and RNA-seq (circular and linear RNAs) were used to perform the profiling study in the discovery cohort and candidates were validated by RT-qPCR in the whole cohort. The biomarker potential of the candidates was evaluated by ROC curve analysis. RNA-seq and RT-qPCR validation revealed that two circular (hsa_circ_0000478 and hsa_circ_0116639) and two linear RNAs (IRF5 and MTRNR2L8) are downregulated in PBMCs from patients with positive LS-OCMBs. Finally, those RNAs show a performance of a 70% accuracy in some of the combinations. The expression of hsa_circ_0000478, hsa_circ_0116639, IRF5 and MTRNR2L8 might serve as minimally invasive biomarkers of highly active disease.

Curcumin Formulations and Trials: What's New in Neurological Diseases

Curcumin’s pharmacological properties and its possible benefits for neurological diseases and dementia have been much debated. In vitro experiments show that curcumin modulates several key physiological pathways of importance for neurology. However, in vivo studies have not always matched expectations. Thus, improved formulations of curcumin are emerging as powerful tools in overcoming the bioavailability and stability limitations of curcumin. New studies in animal models and recent double-blinded, placebo-controlled clinical trials using some of these new formulations are finally beginning to show that curcumin could be used for the treatment of cognitive decline. Ultimately, this work could ease the burden caused by a group of diseases that are becoming a global emergency because of the unprecedented growth in the number of people aged 65 and over worldwide. In this review, we discuss curcumin’s main mechanisms of action and also data from in vivo experiments on the effects of curcumin on cognitive decline.

The role of microRNAs in multiple sclerosis

Despite numerous studies on multiple sclerosis (MS) and understanding many aspects of this disease, researchers still struggle to find proper biomarkers that facilitate diagnosis; prognosis and monitoring of treatment efficacy in MS. MicroRNAs (miRNAs) are considered as endogenous, comparatively stable and small non-coding RNAs involved in various biological and pathological signaling pathways. Interestingly, miRNAs have been emerged as a potential biomarker for monitoring novel therapies in MS patients. In this review, we described the miRNAs alteration in the MS patients as well as their altered expression in patients under common MS therapies.

The Role of Magnesium in Pathophysiology and Migraine Treatment

Migraine is one of the most common recurrent types of headache and is the seventh cause of disability. This neurological disorder is characterized by having pain in head and other various symptoms such as nausea, emesis, photophobia, phonophobia, and sometimes visual sensory disorders. Magnesium (Mg) is a necessary ion for human body and has a crucial role in health and life maintenance. One of the main roles of Mg is to conserve neurons electric potential. Therefore, magnesium deficiency can cause neurological complications. Migraine is usually related to low amounts of Mg in serum and cerebrospinal fluid (CSF). Deficits in magnesium have significant role in the pathogenesis of migraine. Mg has been extensively used in migraine prophylaxis and treatment. This review summarizes the role of Mg in migraine pathogenesis and the potential utilizations of Mg in the prevention and treatment of migraine with the emphasis on transdermal magnesium delivery.

LncRNA GAS5 and miR-137 Polymorphisms and Expression are Associated with Multiple Sclerosis Risk: Mechanistic Insights and Potential Clinical Impact

The pathogenesis of multiple sclerosis (MS) is influenced by the interaction of genetic and epigenetic mechanisms. The long noncoding RNA GAS5 acts as a competing endogenous RNA for microRNA-137 and is involved in demyelination. We investigated the association of GAS5 and miR-137 expression and their polymorphisms with MS susceptibility. One hundred and eight MS patients and 104 healthy controls were included. Expression analysis and genotyping of GAS5-rs2067079 and miR-137-rs1625579 single nucleotide polymorphisms were performed by qPCR. Serum GAS5 was upregulated, while serum miR-137 was downregulated in MS compared with the controls. Serum miR-137 was an excellent discriminator of MS patients from the controls (AUC = 0.97) and a negative independent predictor of MS in multivariate logistic analysis. Serum GAS5 expression was positively correlated with the expanded disability status scale scores in the relapsing-remitting MS patients. The rs2067079TT minor homozygote genotype was associated with an increased MS risk, while the rs1625579G minor allele was protective. rs1625579 showed an age-specific effect, while the rs2067079 affected the MS risk in gender- and age-specific manners. In MS patients, rs2067079TT was associated with a higher serum GAS5 than other genotypes, while serum miR-137 did not differ between rs1625579 genotypes. Our results suggest serum GAS5 and miR-137 as MS biomarkers, with miR-137 as a negative predictor of MS risk and GAS5 as a marker of MS severity. We propose rs2067079 and rs1625579 as novel genetic markers of MS susceptibility, and at least, rs2067079 possibly impacts the crosstalk between GAS5 and miR-137.

Curcumin and neurological diseases

Objectives: The beneficial effects of many substances have been discovered because of regular dietary consumption. This is also the case with curcumin, whose effects have been known for more than 4,000 years in Eastern countries such as China and India. A curcumin-rich diet has been known to counteract many human diseases, including cancer and diabetes, and has been shown to reduce inflammation. The effect of a curcumin treatment for neurological diseases, such as spinal muscular atrophy; Alzheimer's disease; Parkinson's disease; amyotrophic lateral sclerosis; multiple sclerosis; and others, has only recently been brought to the attention of researchers and the wider population.Methods: In this paper, we summarise the studies on this natural product, from its isolation two centuries ago to its characterisation a century later.Results: We describe its role in the treatment of neurological diseases, including its cellular and common molecular mechanisms, and we report on the clinical trials of curcumin with healthy people and patients.Discussion: Commenting on the different approaches adopted by the efforts made to increase its bioavailability.

Cytoplasmic TDP43 Binds microRNAs: New Disease Targets in Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive, fatal, and incurable neurodegenerative disease. Recent studies suggest that dysregulation of gene expression by microRNAs (miRNAs) may play an important role in ALS pathogenesis. The reversible nature of this dysregulation makes miRNAs attractive pharmacological targets and a potential therapeutic avenue. Under physiological conditions, miRNA biogenesis, which begins in the nucleus and includes further maturation in the cytoplasm, involves trans-activation response element DNA/RNA-binding protein of 43 kDa (TDP43). However, TDP43 mutations or stress trigger TDP43 mislocalization and inclusion formation, a hallmark of most ALS cases, that may lead to aberrant protein/miRNA interactions in the cytoplasm. Herein, we demonstrated that TDP43 exhibits differential binding affinity for select miRNAs, which prompted us to profile miRNAs that preferentially bind cytoplasmic TDP43. Using cellular models expressing TDP43 variants and miRNA profiling analyses, we identified differential levels of 65 cytoplasmic TDP43-associated miRNAs. Of these, approximately 30% exhibited levels that differed by more than 3-fold in the cytoplasmic TDP43 models relative to our control model. The hits included both novel miRNAs and miRNAs previously associated with ALS that potentially regulate several predicted genes and pathways that may be important for pathogenesis. Accordingly, these findings highlight specific miRNAs that may shed light on relevant disease pathways and could represent potential biomarkers and reversible treatment targets for ALS.

A Meta-Analytic Review of the Value of miRNA for Multiple Sclerosis Diagnosis

Backgrounds and Purpose: Multiple sclerosis (MS) is an immune-mediated chronic inflammatory demyelinating disease of the central nervous system. The etiology of MS is unclear, disease diagnosis mainly based on symptoms, and lacks effective laboratory test index. Circulating microRNAs (miRNAs) as sensitive biomarkers have been widely studied, the expression levels of certain miRNAs are dynamically changed in MS patients. This meta-analysis aims to assess the overall diagnostic accuracy of circulating miRNAs for MS.

Methods: We searched PubMed, EMBASE, Cochrane Library, CNKI databases as of July 20, 2019. QUADAS was used to assess the quality of included studies. All studies were processed by Stata 15.0 software. Eleven articles with 600 patients with MS and 389 controls were included.

Results: The sensitivity and specificity, PLR, NLR, and DOR of the overall studies were 0.81 (95% CI 0.77–0.84), 0.75 (95% CI 0.68–0.81), 3.3 (95% CI 2.5–4.3), 0.25 (95% CI 0.20–0.32), 13 (95% CI: 8–20), and 0.85 (95% CI 0.82–0.88). Subgroup analysis indicated that miRNA assay had higher diagnostic accuracy for relapsing-remitting MS (RRMS) when compared with other MS subtypes.

Conclusion: Our study performed a meta-analysis to generate an estimate of the relevance of miRNA change and the occurrence of MS, and revealed circulating miRNAs has the potential to be used for MS diagnosis, especially for RRMS. Future studies should clarify to which specific miRNAs can accurately diagnose disease subtypes. The miRNA-related pathogenesis may provide theoretical basis for drug development for early intervention.

MicroRNAs in gray and white matter multiple sclerosis lesions: impact on pathophysiology

Multiple sclerosis (MS) is a chronic disease of the CNS, hallmarked by inflammation and demyelination. Early stages of the disease frequently show active lesions containing numerous foamy macrophages and inflammatory cells. Disease progression is highlighted by increasing numbers of mixed active/inactive or inactive lesions showing sparse inflammation and pronounced astrogliosis. Furthermore, gray matter lesions increase in number and extent during disease progression. MicroRNAs (miRNAs) comprise a group of several thousand (in humans more than 2000), small non-coding RNA molecules with a fundamental influence on about one-third of all protein-coding genes. Furthermore, miRNAs have been detected in body fluids, including spinal fluid, and they are assumed to participate in intercellular communications. Several studies have determined miRNA profiles from dissected white and gray matter lesions of autoptic MS patients. In this review, we summarize in detail the current knowledge of individual miRNAs in gray and white matter lesions of MS patients and present the concepts of MS tissue lesion development based on the altered miRNA profiles. © 2020 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

CSF microRNAs discriminate MS activity and share similarity to other neuroinflammatory disorders

Objective

To perform a comprehensive multicompartment analysis of microRNA (miRNA) expression in multiple sclerosis (MS) linked to disease activity and compared with other neuroinflammatory diseases through a retrospective cross-sectional study.

Methods

One hundred twenty-seven miRNAs were measured by PCR arrays on pooled CSF, serum, and peripheral blood mononuclear cell (PBMC) samples of 10 patients with relapsing MS and 10 controls. Sixty-four miRNAs were then measured by quantitative PCR on individual CSF samples of patients with relapsing or remitting MS and controls (n = 68). Fifty-seven miRNAs were analyzed in the CSF from a second cohort (n = 75), including patients with MS, neuroinfectious, or neuroinflammatory diseases and controls. MiRNAs significantly dysregulated in the CSF were analyzed on individual serum/PBMC samples (n = 59/48) of patients with relapsing or remitting MS and controls. Post hoc analysis consisted of principal component analysis (PCA), gene set, and pathway enrichment analysis.

Results

Twenty-one miRNAs were differentially expressed, mainly upregulated in the CSF during MS relapses. Relapsing MS and neuroinfectious/inflammatory diseases exhibited a partially overlapping CSF miRNA expression profile. Besides confirming the association of miR-146a-5p/150-5p/155-5p with MS, 7 miRNAs uncharacterized for MS emerged (miR-15a-3p/124-5p/149-3p/29c-3p/33a-3p/34c-5p/297). PCA showed that distinct miRNA sets segregated MS from controls and relapse from remission. In silico analysis predicted the involvement of these miRNAs in cell cycle, immunoregulation, and neurogenesis, but also revealed that the signaling pathway pattern of remitting MS is more akin to controls rather than patients with relapsing MS.

Conclusions

This study highlights the CSF-predominant dysregulation of miRNAs in MS by identifying a signature of disease activity and intrathecal inflammation among neuroinflammatory disorders.

Prospects for the application of growth factors in wound healing

As the largest organ of the body, human skin is multifunctional and enjoys two layers, the epidermis and the dermis, the separation of which is performed by a basement membrane zone. Skin protects the body against mechanical forces and infections. Skin wounds represent large and growing challenges to the healthcare systems globally. Skin wound healing, as a protective shield for the body against the external environment, includes interactions among cell types, the neurovascular system, cytokines, and matrix remodeling. Growth factors (GFs) affect the microenvironment of the wound, and cause rises in cell differentiation, proliferation, and migration. Administrating exogenous GFs has revealed potential in enhancing wound healing outcomes. The use of human GFs in the field of wound healing is becoming gradually more interesting, because of the low-invasive techniques required for their use. Reviewed here are the literatures on the healing of skin wounds with emphasize on the role of GFs and their future prospects, containing profits, and probable long-standing side effects accompanied with their use.

The Putative Association of TOB1-AS1 Long Non-coding RNA with Immune Tolerance: A Study on Multiple Sclerosis Patients

The hallmark of multiple sclerosis (MS) pathogenesis is the breakdown of peripheral tolerance in the immune system. However, its molecular mechanism is not completely understood. Since long non-coding RNAs (lncRNAs) has played important roles in regulation of immunological pathways, here, we evaluated the expression of a novel lncRNA, TOB1-AS1, and its putative associated coding genes in the mechanism of maintaining immune tolerance in peripheral blood of MS patients to assess their possible roles in MS pathogenesis. In this study, 39 MS patients and 32 healthy matched controls were recruited. Real-time PCR standard curve method was used to quantify transcript levels of TOB1-AS1, TOB1, SKP2, and TSG. In addition, the potential sex hormone receptor binding sites on target genes promoter were analyzed using JASPR software. This work demonstrates a negative correlation between TOB1-AS1 expression and EDSS of patients. Also, a robust dysregulation of co-expression of TOB1-AS1 lncRNA and the coding genes in MS patients compared to controls was observed. Such dysregulation in this pathway may be related to MS pathogenesis and response to interferon treatment.

microRNA dysregulation in neurodegenerative diseases: A systematic review

While the root causes for individual neurodegenerative diseases are distinct, many shared pathological features and mechanisms contribute to neurodegeneration across diseases. Altered levels of microRNAs, small non-coding RNAs involved in post transcriptional regulation of gene expression, are reported for numerous neurodegenerative diseases. Yet, comparison between diseases to uncover commonly dysregulated microRNAs during neurodegeneration in general is lagging. We performed a systematic review of peer-reviewed publications describing differential microRNA expression in neurodegenerative diseases and related animal models. We compiled the results from studies covering the prevalent neurodegenerative diseases in the literature: Alzheimer's disease, amyotrophic lateral sclerosis, age-related macular degeneration, ataxia, dementia, myotonic dystrophy, epilepsy, glaucoma, Huntington's disease, multiple sclerosis, Parkinson's disease, and prion disorders. MicroRNAs which were dysregulated most often in these diseases and their models included miR-9-5p, miR-21-5p, the miR-29 family, miR-132-3p, miR-124-3p, miR-146a-5p, miR-155-5p, and miR-223-3p. Common pathways targeted by these predominant miRNAs were identified and revealed great functional overlap across diseases. We also identified a strong role for each microRNA in both the neural and immune components of diseases. microRNAs regulate broad networks of genes and identifying microRNAs commonly dysregulated across neurodegenerative diseases could cultivate novel hypotheses related to common molecular mechanisms underlying neurodegeneration.

An unmet clinical need: roads to remyelination in MS

Background

In the central nervous system (CNS) myelin sheaths stabilize, protect, and electrically insulate axons. However, in demyelinating autoimmune CNS diseases such as multiple sclerosis (MS) these sheaths are destroyed which ultimately leads to neurodegeneration. The currently available immunomodulatory drugs for MS effectively control the (auto)inflammatory facets of the disease but are unable to regenerate myelin by stimulating remyelination via oligodendroglial precursor cells (OPCs). Accordingly, there is broad consensus that the implementation of new regenerative approaches constitutes the prime goal for future MS pharmacotherapy.

Main text

Of note, recent years have seen several promising clinical studies investigating the potential of substances and monoclonal antibodies such as, for instance, clemastine, opicinumab, biotin, simvastatin, quetiapin and anti-GNbAC1. However, beyond these agents which have often been re-purposed from other medical indications there is a multitude of further molecules influencing OPC homeostasis. Here, we therefore discuss these possibly beneficial regulators of OPC differentiation and assess their potential as new pharmacological targets for myelin repair in MS.

Conclusion

Remyelination remains the most important therapeutic treatment goal in MS in order to improve clinical deficits and to avert neurodegeneration. The promising molecules presented in this review have the potential to promote remyelination and therefore warrant further translational and clinical research.

miRNA-181a over-expression in mesenchymal stem cell-derived exosomes influenced inflammatory response after myocardial ischemia-reperfusion injury

AIMS

The inflammation modulation effects of mesenchymal stromal cell-derived exosomes (MSC-EXO) are well established. We aimed to explore the mechanism behind the inflammatory responses of numerous exosomal cargo molecules that have been neglected in molecular biology research, and to develop an exosomal cargo delivery system that can exert a stronger therapeutic effect on myocardial ischemia-reperfusion (I/R) injury.

MAIN METHODS

Computational approaches were used to identify key exosomal miRNAs and their downstream mRNAs that are expressed in the inflammatory response. Direct interactions between miRNA-181a and the c-Fos mRNA complex were confirmed by luciferase reporter assay. MSC-EXO carrying miRNA-181a-overexpressing lentiviruses were intramyocardially injected into a mouse model of myocardial I/R injury. I/R progression was evaluated through echocardiography and immunofluorescence microscopy.

KEY FINDINGS

miRNA-181a provided substantial coverage against a host of immune-related genes through the miRNA-mRNA network. miRNA-181a delivery by MSC-EXO combined the immune-suppressing effect of miRNA-181a and the cell targeting capability of MSC-EXO to exert a stronger therapeutic effect on myocardium I/R injury.

SIGNIFICANCE

We showed the potential of MSC-EXO as a tool for the specific delivery of small RNAs in vivo. This study shed new light on the potential application of miRNA-181a-overexpressing MSC-EXO as a therapeutic strategy for myocardial I/R injury.

Epstein-Barr Virus and miRNAs: Partners in Crime in the Pathogenesis of Multiple Sclerosis?

MicroRNAs (miRNAs) are small non-coding RNAs that modulate gene expression post transcriptionally. In healthy individuals, miRNAs contribute to maintaining gene expression homeostasis. However, the level of miRNAs expressed is markedly altered in different diseases, including multiple sclerosis (MS). The impact of such changes is being investigated, and thought to shape the immune system into the inflammatory autoimmune phenotype. Much is yet to be learned about the contribution of miRNAs in the molecular pathology of MS. Epstein-Barr virus (EBV) infection is a major risk factor for the development of MS. EBV encodes more than 40 miRNAs, most of which have been studied in the context of EBV associated cancers. These viral miRNAs regulate genes involved in cell apoptosis, antigen presentation and recognition, as well as B cell transformation. If EBV infection contributes to the pathology of MS, it is plausible that EBV miRNAs may be involved. Unfortunately, there are limited studies addressing how EBV miRNAs are involved in the pathogenesis of MS. This review summarizes what has been reported regarding cellular and viral miRNA profiles in MS and proposes possible interactions between the two in the development of MS.

MiRNAs from DLK1-DIO3 Imprinted Locus at 14q32 are Associated with Multiple Sclerosis: Gender-Specific Expression and Regulation of Receptor Tyrosine Kinases Signaling

Relapsing-remitting multiple sclerosis (RRMS) is the most prevalent course of multiple sclerosis. It is an autoimmune inflammatory disease of the central nervous system. To investigate the gender-specific involvement of microRNAs (miRNAs) in RRMS pathogenesis, we compared miRNA profiles in peripheral blood mononuclear cells separately in men and women (eight RRMS patients versus four healthy controls of each gender) using high-throughput sequencing. In contrast to women, six downregulated and 26 upregulated miRNAs (p_adj < 0.05) were identified in men with RRMS. Genes encoding upregulated miRNAs are co-localized in DLK1-DIO3 imprinted locus on human chromosome 14q32. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis was performed in independent groups of men (16 RRMS patients and 10 healthy controls) and women (20 RRMS patients and 10 healthy controls). Increased expression of miR-431, miR-127-3p, miR-379, miR-376c, miR-381, miR-410 and miR-656 was again demonstrated in male (p_adj < 0.05), but not in female RRMS patients. At the same time, the expression levels of these miRNAs were lower in healthy men than in healthy women, whereas in RRMS men they increased and reached or exceeded levels in RRMS women. In general, we demonstrated that expression levels of these miRNAs depend both on “health–disease” status and gender. Network-based enrichment analysis identified that receptor tyrosine kinases-activated pathways were enriched with products of genes targeted by miRNAs from DLK1-DIO3 locus. These results suggest the male-specific involvement of these miRNAs in RRMS pathogenesis via regulation of PI3K/Akt signaling.