ABSTRACT
Multiple Sclerosis (MS) is a heterogeneous inflammatory and neurodegenerative disease with an unpredictable course towards progressive disability. Treating progressive MS is challenging due to limited insights into the underlying mechanisms. We examined the molecular changes associated with primary progressive MS (PPMS) using a cross-tissue (blood and post-mortem brain) and multilayered data (genetic, epigenetic, transcriptomic) from independent cohorts. In PPMS, we found hypermethylation of the 1q21.1 locus, controlled by PPMS-specific genetic variations and influencing the expression of proximal genes (CHD1L, PRKAB2) in the brain. Evidence from reporter assay and CRISPR/dCas9 experiments supports a causal link between methylation and expression and correlation network analysis further implicates these genes in PPMS brain processes. Knock-down of CHD1L in human iPSC-derived neurons and knock-out of chd1l in zebrafish led to developmental and functional deficits of neurons. Thus, several lines of evidence suggest a distinct genetic-epigenetic-transcriptional interplay in the 1q21.1 locus potentially contributing to PPMS pathogenesis.
Subject(s)
Brain , Chromosomes, Human, Pair 1 , DNA Methylation , DNA-Binding Proteins , Epigenesis, Genetic , Zebrafish , Humans , Zebrafish/genetics , Animals , DNA Methylation/genetics , Chromosomes, Human, Pair 1/genetics , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Brain/metabolism , Brain/pathology , DNA Helicases/genetics , DNA Helicases/metabolism , Neurons/metabolism , Multiple Sclerosis, Chronic Progressive/genetics , Induced Pluripotent Stem Cells/metabolism , Male , Female , Middle Aged , Genetic Predisposition to Disease , AdultABSTRACT
Multiple sclerosis (MS) is a chronic demyelinating autoimmune neurodegenerative disorder for which no specific blood biomarker is available. MicroRNAs (miRNAs) have been investigated for their diagnostic potential in MS. However, MS-associated miRNAs are rarely replicated in different MS populations, thus impeding their use in clinical testing. Here, we evaluated the fold expression of seven reported MS miRNAs associated with MS incidence and clinical characteristics in 76 MS patients and 75 healthy control plasma samples. We found miR-23a-3p to be upregulated in relapsing-remitting MS (RRMS), while miR-326 was downregulated. MiR-150-5p and -320a-3p were significantly downregulated in secondary progressive MS (SPMS) patients compared to RRMS. High disability was associated with low miR-320a-3p, whereas low BDNF levels were associated with upregulation of miR-150-5p and downregulation of miR-326 expression in the total cohort. MiR-23a-3p and miR-326 showed significant diagnostic sensitivity, specificity, and accuracy for RRMS diagnosis. In addition, miR-150-5p and miR-320a-3p had comparable significant diagnostic test performance metrics distinguishing SPMS from RRMS. Therefore, there is potential for including miR-23a-3p and miR-326 in an RRMS diagnostic miRNA panel. Moreover, we have shown that miR-150-5p and miR-320a-3p could be novel RRMS conversion to SPMS biomarkers. The use of these miRNAs in MS diagnosis and prognosis warrants further investigation.
Subject(s)
Biomarkers , MicroRNAs , Multiple Sclerosis , Humans , MicroRNAs/blood , MicroRNAs/genetics , Male , Female , Biomarkers/blood , Adult , Middle Aged , Multiple Sclerosis/genetics , Multiple Sclerosis/blood , Multiple Sclerosis/diagnosis , Multiple Sclerosis, Relapsing-Remitting/blood , Multiple Sclerosis, Relapsing-Remitting/genetics , Multiple Sclerosis, Relapsing-Remitting/diagnosis , Case-Control Studies , Brain-Derived Neurotrophic Factor/blood , Brain-Derived Neurotrophic Factor/genetics , Multiple Sclerosis, Chronic Progressive/blood , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Chronic Progressive/diagnosisABSTRACT
BACKGROUND AND OBJECTIVES: In progressive multiple sclerosis (MS), compartmentalized inflammation plays a pivotal role in the complex pathology of tissue damage. The interplay between epigenetic regulation, transcriptional modifications, and location-specific alterations within white matter (WM) lesions at the single-cell level remains underexplored. METHODS: We examined intracellular and intercellular pathways in the MS brain WM using a novel dataset obtained by integrated single-cell multi-omics techniques from 3 active lesions, 3 chronic active lesions, 3 remyelinating lesions, and 3 control WM of 6 patients with progressive MS and 3 non-neurologic controls. Single-nucleus RNA-seq and ATAC-seq were combined and additionally enriched with newly conducted spatial transcriptomics from 1 chronic active lesion. Functional gene modules were then validated in our previously published bulk tissue transcriptome data obtained from 73 WM lesions of patients with progressive MS and 25 WM of non-neurologic disease controls. RESULTS: Our analysis uncovered an MS-specific oligodendrocyte genetic signature influenced by the KLF/SP gene family. This modulation has potential associations with the autocrine iron uptake signaling observed in transcripts of transferrin and its receptor LRP2. In addition, an inflammatory profile emerged within these oligodendrocytes. We observed unique cellular endophenotypes both at the periphery and within the chronic active lesion. These include a distinct metabolic astrocyte phenotype, the importance of FGF signaling among astrocytes and neurons, and a notable enrichment of mitochondrial genes at the lesion edge populated predominantly by astrocytes. Our study also identified B-cell coexpression networks indicating different functional B-cell subsets with differential location and specific tendencies toward certain lesion types. DISCUSSION: The use of single-cell multi-omics has offered a detailed perspective into the cellular dynamics and interactions in MS. These nuanced findings might pave the way for deeper insights into lesion pathogenesis in progressive MS.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , White Matter , Humans , Multiple Sclerosis/genetics , Multiple Sclerosis/pathology , Epigenesis, Genetic , Multiomics , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Chronic Progressive/pathology , White Matter/pathologyABSTRACT
Multiple sclerosis (MS) is a complex inflammatory disease affecting the central nervous system. Most commonly, it begins with recurrent symptoms followed by partial or complete recovery, known as relapsing-remitting MS (RRMS). Over time, many RRMS patients progress to secondary progressive MS (SPMS), marked by gradual symptom deterioration. The factors triggering this transition remain unknown, lacking predictive biomarkers. This study aims to identify blood biomarkers specific to SPMS. We analyzed six datasets of SPMS and RRMS patients' blood and brain tissues, and compared the differential expressed genes (DEGs) obtained to highlight DEGs reflecting alterations occurring in both brain and blood tissues and the potential biological processes involved. We observed a total of 38 DEGs up-regulated in both blood and brain tissues, and their interaction network was evaluated through network analysis. Among the aforementioned DEGs, 21 may be directly involved with SPMS transition. Further, we highlighted three biological processes, including the calcineurin-NFAT pathway, related to this transition. The investigated DEGs may serve as a promising means to monitor the transition from RRMS to SPMS, which is still elusive. Given that they can also be sourced from blood samples, this approach could offer a relatively rapid and convenient method for monitoring MS and facilitating expedited assessments.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Humans , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis/diagnosis , Multiple Sclerosis, Relapsing-Remitting/metabolism , Brain/metabolism , BiomarkersABSTRACT
Multiple sclerosis (MS) is a chronic autoimmune inflammatory and neurodegenerative disease of the central nervous system, which is characterized by significant clinical heterogeneity. Primary progressive MS (PPMS) develops in 10-15% of patients. Unlike the most common relapsing-remitting form of MS, PPMS involves steady progress of neurodegeneration and, as a consequence, a persistent gradual increase in neurological symptoms. The peculiarities of epigenetic regulation of gene expression may be one of the reasons for the differences in the pathogenesis of the two MS forms. DNA methylation is one of the key epigenetic mechanisms, which remains almost unexplored in different cell populations of PPMS patients. The goal of this work was to identify differential methylation profiles of the CpG sites in the CD14+ monocyte DNA, which characterize PPMS. A genome-wide analysis of DNA methylation in PPMS patients and healthy individuals has identified 169 differentially methylated positions (DMPs), 90.5% of which were hypermethylated in PPMS patients. More than half of all DMPs are located in/near known genes and within CpG islands and their neighboring regions, which indicates their high functional significance. We have found six differentially methylated regions (DMRs) in the OR2L13, CAT, LCLAT1, HOXA5, RNF39, and CRTAC1 genes involved in inflammation and neurodegeneration, which indicates active epigenetic regulation of their expression.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Neurodegenerative Diseases , Humans , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Relapsing-Remitting/genetics , Epigenesis, Genetic , DNA Methylation , Monocytes , Neurodegenerative Diseases/genetics , Calcium-Binding Proteins/geneticsABSTRACT
Multiple Sclerosis (MS) is a common immune-mediated disorder of the central nervous system that affects young adults and is characterized by demyelination and neurodegeneration. Recent studies have associated C9orf72 intermediate repeat expansions with MS. The objective of this study was to investigate whether C9orf72 repeat length is associated with MS or with a specific disease course in a monocentric Austrian MS cohort. Genotyping of 382 MS patients and 643 non-neurological controls for C9orf72 repeat expansions was performed. The study did not find a difference in the distribution of repeat numbers between controls and MS cases (median repeat units = 2; p = 0.39). Additionally, sub-analysis did not establish a link between intermediate repeats and MS (p = 0.23) and none of the patients with progressive disease course carried an intermediate allele (20-30 repeat units). Exploratory analysis for different cut-offs (of ≥7, ≥17, and ≥24) did not reveal any significant differences in allele frequencies between MS and controls. However, the study did identify a progressive MS patient with a pathogenic C9orf72 expansion and probable co-existing behavioral variant frontotemporal dementia (bvFTD) in a retrospective chart review. In conclusion, this study did not find evidence supporting an association between C9orf72 repeat length and MS or a specific disease course in the Austrian MS cohort. However, the identification of a progressive MS patient with a pathogenic C9orf72 expansion and probable co-existing with FTD highlights the complexity and challenges involved in recognizing distinct neurodegenerative diseases that may co-occur in MS patients.
Subject(s)
C9orf72 Protein , Multiple Sclerosis , Humans , Amyotrophic Lateral Sclerosis/genetics , Austria , C9orf72 Protein/genetics , Frontotemporal Dementia/genetics , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/genetics , Retrospective StudiesABSTRACT
BACKGROUND: The two main phenotypes of multiple sclerosis (MS), primary progressive (PPMS) and relapsing Onset (ROMS), show clinical and demographic differences suggesting possible differential risk mechanisms. Understanding the heritable features of these phenotypes could provide aetiological insight. OBJECTIVES: To evaluate the magnitude of familial components in PPMS and ROMS and to estimate the heritability of disease phenotypes. METHODS: We used data from 25,186 MS patients of Nordic ancestry from the Swedish MS Registry between 1987 and 2019 with known disease phenotype (1593 PPMS and 16,718 ROMS) and 251,881 matched population-based controls and 3,364,646 relatives of cases and controls. Heritability was calculated using threshold-liability models. For familial odds ratios (ORs), logistic regression with robust sandwich estimator was utilized. RESULTS: The OR of MS diagnosis in those with a first-degree family member with ROMS was 7.00 and 8.06 in those with PPMS. The corresponding ORs for having a second-degree family member with ROMS was 2.16 and 2.18 in PPMS. The additive genetic effect in ROMS was 0.54 and 0.22 in PPMS. CONCLUSION: Risk of MS increases by several folds in those with a relative with MS. The likelihood of developing either disease phenotype appears independent of genetic predisposition.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , Humans , Multiple Sclerosis/epidemiology , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/epidemiology , Multiple Sclerosis, Chronic Progressive/genetics , Case-Control Studies , Genetic Predisposition to Disease , Disease Progression , Phenotype , Multiple Sclerosis, Relapsing-Remitting/geneticsABSTRACT
Cognitive impairment is a common and debilitating feature of multiple sclerosis (MS), and the dysregulation of synaptic plasticity is one of its direct causes. Long non-coding RNAs (lncRNAs) have been shown to play a role in synaptic plasticity, but their role in cognitive impairment in MS has not been fully explored. In this study, using quantitative real-time PCR, we examined the relative expression of two specific lncRNAs, BACE1-AS and BC200, in the serum of two cohorts of MS patients with and without cognitive impairment. Both lncRNAs were overexpressed in both cognitively impaired and non-cognitively impaired MS patients, with consistently higher levels in the cohort with cognitive impairment. We also found a strong positive correlation between the expression levels of these two lncRNAs. Notably, BACE1-AS was consistently higher in the remitting cases of both relapsing-remitting MS (RRMS) and secondary progressive MS (SPMS) groups than in the respective relapse cases of the same subtype, with the SPMS-Remitting group of cognitively impaired MS patients showing the highest expression of BACE1-AS among all MS groups. Additionally, we observed that the primary progressive MS (PPMS) group had the highest expression of BC200 in both cohorts of MS. Furthermore, we developed a model called Neuro_Lnc-2, which showed better diagnostic performance than either BACE1-AS or BC200 alone in predicting MS. Our findings suggest that these two lncRNAs may have a significant impact on the pathogenesis of the progressive types of MS and on the cognitive function of the patients. Future research is required to confirm these findings.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis, Relapsing-Remitting , Multiple Sclerosis , RNA, Long Noncoding , Humans , Multiple Sclerosis/genetics , RNA, Long Noncoding/genetics , Amyloid Precursor Protein Secretases/genetics , Aspartic Acid Endopeptidases/genetics , Multiple Sclerosis, Chronic Progressive/complications , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Relapsing-Remitting/genetics , Cognition , Gene Expression ProfilingABSTRACT
BACKGROUND AND OBJECTIVES: Primary progressive multiple sclerosis (PPMS) displays a highly variable disease progression with a characteristic accumulation of disability, what makes difficult its diagnosis and efficient treatment. The identification of microRNAs (miRNAs)-based signature for the early detection in biological fluids could reveal promising biomarkers to provide new insights into defining MS clinical subtypes and potential therapeutic strategies. The objective of this cross-sectional study was to describe PPMS miRNA profiles in CSF and serum samples compared with other neurologic disease individuals (OND) and relapsing-remitting MS (RRMS). METHODS: First, a screening stage analyzing multiple miRNAs in few samples using OpenArray plates was performed. Second, individual quantitative polymerase chain reactions (qPCRs) were used to validate specific miRNAs in a greater number of samples. RESULTS: A specific profile of dysregulated circulating miRNAs (let-7b-5p and miR-143-3p) was found downregulated in PPMS CSF samples compared with OND. In addition, in serum samples, miR-20a-5p and miR-320b were dysregulated in PPMS against RRMS and OND, miR-26a-5p and miR-485-3p were downregulated in PPMS vs RRMS, and miR-142-5p was upregulated in RRMS compared with OND. DISCUSSION: We described a 2-miRNA signature in CSF of PPMS individuals and several dysregulated miRNAs in serum from patients with MS, which could be considered valuable candidates to be further studied to unravel their actual role in MS. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that specific miRNA profiles accurately distinguish PPMS from RRMS and other neurologic disorders.
Subject(s)
MicroRNAs , Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , Humans , Biomarkers/blood , Biomarkers/cerebrospinal fluid , Cross-Sectional Studies , MicroRNAs/blood , MicroRNAs/cerebrospinal fluid , MicroRNAs/genetics , Multiple Sclerosis/blood , Multiple Sclerosis/cerebrospinal fluid , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/blood , Multiple Sclerosis, Chronic Progressive/cerebrospinal fluid , Multiple Sclerosis, Chronic Progressive/genetics , RecurrenceABSTRACT
Multiple sclerosis (MS) is an auto-immune inflammatory disorder affecting the central nervous system. The cause of the disease is unknown but both genetic and environmental factors are implicated in the pathogenesis. We derived cerebral organoids from induced pluripotent stem cells (iPSC) of healthy control subjects as well as from primary progressive MS (PPMS), secondary progressive MS (SPMS) and relapsing remitting MS (RRMS) patients to better understand the pathologic basis of the varied clinical phenotypic expressions of MS. In MS organoids, most notably in PPMS, we observed a decrease of proliferation marker Ki67 and a reduction of the SOX2+ stem cell pool associated with an increased expression of neuronal markers CTIP2 and TBR1 as well as a strong decrease of oligodendrocyte differentiation. This dysregulation of the stem cell pool is associated with a decreased expression of the cell cycle inhibitor p21. Our findings show that the genetic background of a patient can directly alter stem cell function, provides new insights on the innate cellular dysregulation in MS and identifies p21 pathway as a new potential target for therapeutic strategies in MS.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , Humans , Multiple Sclerosis, Chronic Progressive/genetics , Stem Cells , Cell Differentiation , Organoids , OligodendrogliaABSTRACT
BACKGROUND: Multiple sclerosis (MS) is an aggressive disease characterized by central nervous system (CNS) inflammatory and demyelinating lesions. Tolerance failure is implicated in the development of several autoimmune disorders, including MS. Due to their involvement in maintaining environmental tolerance, regulatory T cells (Tregs) are regarded as efficient immune cells. We examined the frequency of Tregs in this study using CD4/CD25/forkhead box protein P3 (FOXP3)/Helios markers. METHODS: Fifty participants, including 25 patients with secondary progressive MS (SPMS) and 25 healthy controls (HCs), were enrolled in this study, and their demographic characteristics were recorded. Peripheral blood samples ranging from 5 to 6 mL were obtained, and the Ficoll technique was used to extract peripheral blood mononuclear cells (PBMCs). Then, the percentage of CD4+CD25+FOXP3+Helios+ regulatory T lymphocytes was examined by flow cytometry in the study groups. Real-time polymerase chain reaction (PCR) was also used to assess the Helios gene expression level. RESULTS: This study showed that the percentage of Tregs with CD4 and CD25 markers did not reveal a significant difference compared with HCs despite the decrease in SPMS patients (P = 0.6). However, lymphocytes with CD4/CD25/FOXP3/Helios markers were significantly reduced in the patients (P = 0.01). Additionally, SPMS patients had statistically significantly lower Helios gene expression levels (P = 0.002). CONCLUSION: In SPMS patients, a decrease in the frequency of the CD4+CD25+FOXP3+Helios+ Treg population can result in an imbalanced immune system. In other words, one of the immunological mechanisms involved in this disease may be a deficiency in Tregs. Helios gene expression was also decreased in these patients, which may exacerbate functional defects in Tregs.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , Humans , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Gene Expression , Leukocytes, Mononuclear/metabolism , Multiple Sclerosis/genetics , Multiple Sclerosis/metabolism , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Chronic Progressive/metabolism , T-Lymphocytes, RegulatoryABSTRACT
Multiple sclerosis (MS) is the most common inflammatory, demyelinating and neurodegenerative disease of the central nervous system in young adults. Chronic-relapsing experimental autoimmune encephalomyelitis (crEAE) in Biozzi ABH mice is an experimental model of MS. This crEAE model is characterized by an acute phase with severe neurological disability, followed by remission of disease, relapse of neurological disease and remission that eventually results in a chronic progressive phase that mimics the secondary progressive phase (SPEAE) of MS. In both MS and SPEAE, the role of microglia is poorly defined. We used a crEAE model to characterize microglia in the different phases of crEAE phases using morphometric and RNA sequencing analyses. At the initial, acute inflammation phase, microglia acquired a pro-inflammatory phenotype. At the remission phase, expression of standard immune activation genes was decreased while expression of genes associated with lipid metabolism and tissue remodeling were increased. Chronic phase microglia partially regain inflammatory gene sets and increase expression of genes associated with proliferation. Together, the data presented here indicate that microglia obtain different features at different stages of crEAE and a particularly mixed phenotype in the chronic stage. Understanding the properties of microglia that are present at the chronic phase of EAE will help to understand the role of microglia in secondary progressive MS, to better aid the development of therapies for this phase of the disease.
Subject(s)
Encephalomyelitis, Autoimmune, Experimental , Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , Neurodegenerative Diseases , Mice , Animals , Multiple Sclerosis/genetics , Microglia/metabolism , Multiple Sclerosis, Chronic Progressive/genetics , Mice, Biozzi , Encephalomyelitis, Autoimmune, Experimental/metabolism , Gene Expression , Disease Models, AnimalABSTRACT
Siponimod is a selective immunosuppressive medication, developed as the first oral therapy for active secondary progressive multiple sclerosis. This medication acts by modulating the sphingosine 1 phosphate (S1P) receptor, as an antagonist of S1P1 and S1P5, thus preventing the egress of lymphocytes from lymph nodes and preventing inflammatory processes in the Central Nervous System that trigger demyelination. There is extensive scientific knowledge regarding the administration of the medication to patients, which will depend on their pharmacogenetic characteristics. Therefore, the FDA strongly recommends conducting a genotyping study of the enzyme that metabolizes siponimod, CYP2C9, whose genetic variants *2 and *3 classify patients as poor, extensive, or rapid metabolizers. Siponimod is completely contraindicated for patients who are homozygous for CYP2C9*3. Additionally, before prescribing it, an electrocardiogram, assessments of antibody status, ophthalmic evaluation, varicella vaccination status, and peripheral lymphocyte count should be conducted, as the medication's effect is dose-dependent. Therefore, a titration process is carried out starting from 0.25mg up to 2 mg. The pharmacotherapeutic protocol of siponimod is a reliable reflection of the utility of pharmacogenetics in personalized medicine.
Subject(s)
Azetidines , Benzyl Compounds , Multiple Sclerosis, Chronic Progressive , Humans , Benzyl Compounds/administration & dosage , Benzyl Compounds/therapeutic use , Azetidines/administration & dosage , Azetidines/therapeutic use , Multiple Sclerosis, Chronic Progressive/drug therapy , Multiple Sclerosis, Chronic Progressive/genetics , Immunosuppressive Agents/therapeutic use , Immunosuppressive Agents/administration & dosage , Sphingosine 1 Phosphate Receptor Modulators/administration & dosage , Sphingosine 1 Phosphate Receptor Modulators/therapeutic use , Pharmacogenetics , Dose-Response Relationship, DrugABSTRACT
INTRODUCTION: Among numerous invasive procedures for the research of biomarkers, blood-based indicators are regarded as marginally non-invasive procedures in the diagnosis and prognosis of demyelinating disorders, including multiple sclerosis (MS). In this study, we looked into the blood-derived gene expression profiles of patients with multiple sclerosis to investigate their clinical traits and linked them with dysregulated gene expressions to establish diagnostic and prognostic indicators. METHODS: We included 51 patients with relapsing-remitting MS (RRMS, n = 31), clinically isolated syndrome (CIS, n = 12), primary progressive MS (PPMS, n = 8) and a control group (n = 51). Using correlational analysis, the transcriptional patterns of chosen gene panels were examined and subsequently related with disease duration and the expanded disease disability score (EDSS). In addition, principal component analysis, univariate regression, and logistic regression analysis were employed to highlight distinct profiles of genes and prognosticate the excellent biomarkers of this illness. RESULTS: Our findings demonstrated that neurofilament light (NEFL), tumor necrosis factor α (TNF-α), Tau, and clusterin (CLU) were revealed to be increased in recruited patients, whereas the presenilin-1 (PSEN1) and cell-surface glycoprotein-44 (CD44) were downregulated. Principal Component Analysis revealed distinct patterns between the MS and control groups. Correlation analysis indicated co-dependent dysregulated genes and their differential expression with clinical findings. Furthermore, logistic regression demonstrated that Clusterin (AUC=0.940), NEFL (AUC=0.775), TNF-α (AUC=0.817), Tau (AUC=0.749), PSEN1 (AUC=0.6913), and CD44 (AUC=0.832) had diagnostic relevance. Following the univariate linear regression, a significant regression equation was found between EDSS and IGF-1 (R2 adj = 0.10844; p= 0.0060), APP (R2 adj = 0.1107; p= 0.0098), and PSEN1 (R2 adj = 0.1266; p=0.0102). CONCLUSION: This study exhibits dynamic gene expression patterns that represent the significance of specified genes that are prospective diagnostic and prognostic biomarkers for multiple sclerosis.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , Biomarkers , Clusterin , Gene Expression , Gene Expression Profiling/methods , Humans , Multiple Sclerosis/blood , Multiple Sclerosis/diagnosis , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/blood , Multiple Sclerosis, Chronic Progressive/diagnosis , Multiple Sclerosis, Chronic Progressive/genetics , Prognosis , Prospective Studies , Tumor Necrosis Factor-alphaABSTRACT
The pathogenesis of multiple sclerosis (MS), a chronic disease of the CNS, includes autoimmune and neurodegenerative components. In most cases, patients develop relapsing-remitting MS (RRMS), while 10-15% of patients develop primary progressive MS (PPMS), which differs from RRMS in the mechanisms of the pathological process, some demographic, and some clinical characteristics. These differences may be explained by the epigenetic regulation of gene expression in PPMS including DNA methylation as one of the key epigenetic processes. The features of DNA methylation in various cell populations in PPMS patients remain understudied. The goal of this study is to identify differentially methylated CpG sites (DMSs) of the genome of CD4+ T lymphocytes, which characterize PPMS. The study included eight treatment-naive PPMS patients and eight healthy controls. Genome-wide analysis of DNA methylation of CD4+ T lymphocytes was performed using high-density DNA microarrays. We have identified 108 DMSs, which distinguish PPMS patients from healthy controls. In PPMS patients 81% of the DMSs are hypermethylated. More than a half of the identified DMSs are located in known genes in CpG islands and adjacent regions, which indicates a high functional significance of these DMSs in PPMS development. Analysis of the overrepresentation of DMS-containing genes in the main biological processes demonstrates their involvement in the regulation of cell adhesion to the extracellular matrix and the development of the immune response, i.e., antigen processing and presentation, and development of the immune system. Genome-wide analysis of DNA methylation in CD4+ T lymphocytes of PPMS patients indicates the involvement of this epigenetic process in the immunopathogenesis of the disease. These results may help better understand the pathogenesis of this severe form of MS.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , CD4-Positive T-Lymphocytes/metabolism , DNA Methylation , Epigenesis, Genetic , Humans , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/geneticsABSTRACT
BACKGROUND: Secondary progressive multiple sclerosis (SPMS) is the second most common presentation of multiple sclerosis (MS) and is characterized by a gradually deteriorating disease with or without relapses. Approximately 80% of patients with relapsing-remitting MS (RRMS) develop SPMS within 20 years. Epidemiological investigations have revealed an average 7-year life expectancy decrease (more severe in progressive subtypes) in patients with MS. Studies have focused on the neurodegenerative pathogenesis of SPMS; and epigenetic changes have been associated with disease progression in neurodegenerative disorders. However, the evidence for the association between epigenetic changes and SPMS is scarce. Thus, in this study we aimed to identify the key epigenetic genes in SPMS. METHODS: We downloaded DNA methylation and gene expression matrices from the Gene Expression Omnibus (GEO) database. We used bioinformatic analyses to identify key epigenetic genes associated with overall survival (OS) in patients with SPMS. RESULTS: We found 49 differentially methylated positions (DMPs) between the SPMS and control GSE40360 datasets. We used the wANNOVAR server to obtain 64 methylated genes. We merged the gene expression datasets (GSE131282 and GSE135511) in the NetworkAnalyst platform and found 12,442 differentially-expressed genes (DEGs) between SPMS and controls using the Fisher's method, fixed effect model, Vote counting, and direct merging methods. Moreover, we identified 21 epigenetic genes (all hyper-methylated) after an integrating analysis of DMPs and DEGs of patients with SPMS. We established an epigenetic gene signature associated with the OS of patients with SPMS including six hyper-methylated genes (ITGA6, PPP1R16B, RNF126, ABHD8, FOXK1, and SLC6A19) based on the LASSO-Cox method. The calculated individual risk scores were associated with Oss, and we divided patients into high- and low-risk groups on the basis of the mean cut-off value. The six key epigenetic genes were significantly associated with gender, disease duration, and age at death via Spearman correlation analyses. In addition, survival analyses revealed a significant OS difference between high- and low-risk groups. The ROC curves indicated good performance for this predictive model. CONCLUSION: We identified 21 hyper-methylated genes in patients with SPMS via an integrated analysis of DNA methylation and gene expression datasets. We identified a six-epigenetic gene signature that predicts the individual OS with good accuracy. These results indicated that epigenetic modifications play a vital role in the disease progression of SPMS.
Subject(s)
DNA Methylation/genetics , Gene Expression Profiling/methods , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Chronic Progressive/mortality , Transcriptome , Adult , Computational Biology , Female , Humans , Male , Middle AgedABSTRACT
BACKGROUND AND PURPOSE: The NOX2 enzyme of myeloid cells generates reactive oxygen species (ROS) that have been implicated in the pathology of multiple sclerosis (MS). We aimed to determine the impact of genetic variation within CYBA, which encodes the functional CYBA/p22phox subunit of NOX2, on MS severity and progression. METHODS: One hundred three MS patients with up to 49 (median = 17) years follow-up time from first MS diagnosis were genotyped at the single nucleotide polymorphisms rs1049254 and rs4673 within CYBA. Results were matched with disease severity and time to diagnosis of secondary progressive MS (SPMS). NOX2-mediated formation of ROS was measured by chemiluminescence in blood myeloid cells from healthy donors (n = 55) with defined genotypes at rs1049254 and rs4673. RESULTS: The rs1049254/G and rs4673/A CYBA alleles were associated with reduced formation of ROS and were thus defined as low-ROS alleles. Patients carrying low-ROS alleles showed reduced multiple sclerosis severity score (p = 0.02, N = 103, linear regression) and delayed onset of SPMS (p = 0.02, hazard ratio [HR] = 0.46, n = 100, log-rank test). In a cohort examined after 2005, patients carrying low-ROS CYBA alleles showed >20 years longer time to secondary progression (p = 0.003, HR = 0.29, n = 59, log-rank test). CONCLUSIONS: These results implicate NOX2 in MS, in particular for the development of secondary progressive disease, and point toward NOX2-reductive therapy aiming to delay secondary progression.
Subject(s)
Multiple Sclerosis, Chronic Progressive , Multiple Sclerosis , NADPH Oxidases , Genotype , Humans , Multiple Sclerosis/genetics , Multiple Sclerosis, Chronic Progressive/genetics , NADPH Oxidases/genetics , Polymorphism, Single Nucleotide , Reactive Oxygen SpeciesABSTRACT
Introduction: Brain-derived neurotrophic factor (BDNF) levels are reduced in advanced stages of multiple sclerosis (MS) and may be associated with reduced regenerative capability in progressive MS. This has brought increased attention to factors regulating BDNF production in MS. Our aim was to investigate the link between neurotrophin-regulating microRNAs (miRNA) and disease progression in MS. Materials and Methods: Serum levels of BDNF and peripheral blood mononuclear cell (PBMC) expression levels of miR-132-3p, miR-106b-5p and miR-19b-3p were respectively measured by ELISA and real time PCR in twelve relapsing remitting MS (RRMS) patients, seven secondary progressive MS (SPMS) patients and fourteen healthy controls. Results: Serum BDNF levels were significantly reduced in SPMS patients, while selected miRNAs were significantly upregulated in PBMC of RRMS and SPMS patients. miR-106b-5p and miR-19b-3p respectively showed the highest sensitivity and specificity for MS diagnosis by receiver operating characteristic curve analysis. There was a negative correlation between levels of BDNF and the miRNAs in RRMS. Likewise, levels of BDNF and the investigated miRNAs showed positive and negative correlations respectively with the expanded disability status scale in RRMS and SPMS patients. miR-132-3p and miR-106b-5p levels showed positive correlations with the progression index in SPMS patients. Conclusion: Our results suggest that increased disability is associated with downregulation of miR-132-3p, miR-106b-5p and miR-19b-3p in RRMS patients and putatively promotes increased production of neuroprotective BDNF as a compensatory mechanism. This link between the investigated miRNAs and BDNF in RRMS does not appears to hold for SPMS. This might be one of the factors contributing to reduced regenerative ability in the progressive stage of MS.
Subject(s)
Brain-Derived Neurotrophic Factor/blood , MicroRNAs/blood , Multiple Sclerosis, Chronic Progressive/blood , Multiple Sclerosis, Relapsing-Remitting/blood , Adult , Brain-Derived Neurotrophic Factor/genetics , Down-Regulation , Female , Humans , Male , MicroRNAs/genetics , Middle Aged , Multiple Sclerosis, Chronic Progressive/genetics , Multiple Sclerosis, Relapsing-Remitting/genetics , Pilot ProjectsABSTRACT
Multiple sclerosis (MS) is a debilitating neurodegenerative, highly heterogeneous disease with a variable course. The most common MS subtype is relapsing-remitting (RR), having interchanging periods of worsening and relative stabilization. After a decade, in most RR patients, it alters into the secondary progressive (SP) phase, the most debilitating one with no clear remissions, leading to progressive disability deterioration. Among the greatest challenges for clinicians is understanding disease progression molecular mechanisms, since RR is mainly characterized by inflammatory processes, while in SP, the neurodegeneration prevails. This is especially important because distinguishing RR from the SP subtype early will enable faster implementation of appropriate treatment. Currently, the MS course is not well-correlated with the biomarkers routinely used in clinical practice. Despite many studies, there are still no reliable indicators correlating with the disease stage and its activity degree. Circulating microRNAs (miRNAs) may be considered valuable molecules for the MS diagnosis and, presumably, helpful in predicting disease subtype. MiRNA expression dysregulation is commonly observed in the MS course. Moreover, knowledge of diverse miRNA panel expression between RRMS and SPMS may allow for deterring disability progression through successful treatment. Therefore, in this review, we address the current state of research on differences in miRNA panel expression between the phases.