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1.
Commun Biol ; 7(1): 813, 2024 Jul 04.
Article in English | MEDLINE | ID: mdl-38965401

ABSTRACT

Strategies for treating progressive multiple sclerosis (MS) remain limited. Here, we found that miR-145-5p is overabundant uniquely in chronic lesion tissues from secondary progressive MS patients. We induced both acute and chronic demyelination in miR-145 knockout mice to determine its contributions to remyelination failure. Following acute demyelination, no advantage to miR-145 loss could be detected. However, after chronic demyelination, animals with miR-145 loss demonstrated increased remyelination and functional recovery, coincident with altered presence of astrocytes and microglia within the corpus callosum relative to wild-type animals. This improved response in miR-145 knockout animals coincided with a pathological upregulation of miR-145-5p in wild-type animals with chronic cuprizone exposure, paralleling human chronic lesions. Furthermore, miR-145 overexpression specifically in oligodendrocytes (OLs) severely stunted differentiation and negatively impacted survival. RNAseq analysis showed altered transcriptome in these cells with downregulated major pathways involved in myelination. Our data suggest that pathological accumulation of miR-145-5p is a distinctive feature of chronic demyelination and is strongly implicated in the failure of remyelination, possibly due to the inhibition of OL differentiation together with alterations in other glial cells. This is mirrored in chronic MS lesions, and thus miR-145-5p serves as a potential relevant therapeutic target in progressive forms of MS.


Subject(s)
Demyelinating Diseases , Disease Models, Animal , Mice, Knockout , MicroRNAs , Remyelination , MicroRNAs/genetics , MicroRNAs/metabolism , Animals , Remyelination/genetics , Mice , Demyelinating Diseases/genetics , Demyelinating Diseases/metabolism , Demyelinating Diseases/pathology , Humans , Oligodendroglia/metabolism , Oligodendroglia/pathology , Recovery of Function , Male , Mice, Inbred C57BL , Cuprizone/toxicity , Female , Chronic Disease , Myelin Sheath/metabolism
2.
Niger J Clin Pract ; 27(6): 696-701, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38943292

ABSTRACT

BACKGROUND: Demyelinating disorders of the central nervous system (CNS) are rare disorders characterized by inflammation and the selective destruction of CNS myelin. The incidence of this disorder is increasing in developed countries. Nigerian studies on the pediatric population on the subject are very scarce. AIMS: The aim of the study was to document the epidemiology, clinical profile, and impact of late presentation on the treatment outcome of demyelinating diseases of the CNS in pediatric patients. METHODS: The retrospective review of patients aged 1-15 years admitted in a tertiary hospital from January 2018 to December 2022 with various symptoms suggestive of demyelinating CNS disorders. The diagnosis was clinically and radiologically confirmed. Information retrieved from the case notes included patients' demographics, clinical symptoms and signs, number of days with symptoms to presentation in the hospital, results of the magnetic resonance imaging (MRI), treatment, and treatment outcomes. Data were entered in Excel sheet and results were presented in tables and percentages. RESULTS: The incidence of demyelinating disorders over the period was 0.013% (10 out of 769 patients admitted over the period). Acute demyelinating encephalomyelitis (ADEM) was the most common disorder seen in the study population (60%, n = 6), followed by transverse myelitis and two (20%) had optic neuritis (ON). Most of the patients with ADEM were in the 1-5-year age group. The female-to-male ratio was 2.3:1. Paraplegia, visual impairment, and ataxia were the most common clinical presentations in the study population. One of the patients met the criteria for the diagnosis of multiple sclerosis during follow-up. Human immunodeficiency virus (HIV) was identified as the cause of demyelination in one case. Most of the patients improved with steroids. CONCLUSION: ADEM was the most common clinical phenotype seen in this study. Patients with ADEM and ON had a better prognosis than transverse myelitis. Late presentation was also identified as a poor prognostic factor. Follow-up of cases is very important to monitor disease progression to multiple sclerosis.


Subject(s)
Demyelinating Diseases , Humans , Nigeria/epidemiology , Child , Female , Male , Adolescent , Child, Preschool , Retrospective Studies , Infant , Demyelinating Diseases/epidemiology , Demyelinating Diseases/diagnosis , Magnetic Resonance Imaging , Incidence , Treatment Outcome , Myelitis, Transverse/epidemiology , Myelitis, Transverse/diagnosis , Optic Neuritis/epidemiology , Optic Neuritis/diagnosis
3.
Sci Rep ; 14(1): 14649, 2024 06 25.
Article in English | MEDLINE | ID: mdl-38918552

ABSTRACT

Cognitive impairment (CI) is prevalent in central nervous system demyelinating diseases, such as multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD). We developed a novel tablet-based modified digital Symbol Digit Modalities Test (MD-SDMT) with adjustable protocols that feature alternating symbol-digit combinations in each trial, lasting one or two minutes. We assessed 144 patients (99 with MS and 45 with NMOSD) using both MD-SDMT protocols and the traditional paper-based SDMT. We also gathered participants' feedback through a questionnaire regarding their preferences and perceived reliability. The results showed strong correlations between MD-SDMT and paper-based SDMT scores (Pearsons correlation: 0.88 for 2 min; 0.85 for 1 min, both p < 0.001). Among the 120 respondents, the majority preferred the digitalized SDMT (55% for the 2 min, 39% for the 1 min) over the paper-based version (6%), with the 2 min MD-SDMT reported as the most reliable test. Notably, patients with NMOSD and older individuals exhibited a preference for the paper-based test, as compared to those with MS and younger patients. In summary, even with short test durations, the digitalized SDMT effectively evaluates cognitive function in MS and NMOSD patients, and is generally preferred over the paper-based method, although preferences may vary with patient characteristics.


Subject(s)
Multiple Sclerosis , Neuromyelitis Optica , Humans , Male , Female , Adult , Middle Aged , Multiple Sclerosis/psychology , Multiple Sclerosis/physiopathology , Neuromyelitis Optica/physiopathology , Neuropsychological Tests , Cognitive Dysfunction/diagnosis , Reproducibility of Results , Aged , Demyelinating Diseases , Surveys and Questionnaires , Young Adult , Computers, Handheld
4.
Clin Nutr ESPEN ; 62: 108-114, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38901931

ABSTRACT

Diet and inflammation may contribute to the development of multiple sclerosis (MS). The aim of this systematic review and meta-analysis was to assess the association between proinflammatory diet, as estimated by the Dietary Inflammatory Index (DII®), and the likelihood of developing MS or other demyelinating autoimmune diseases. A systematic search was performed of search engines and databases (PubMed, ISI Web of Sciences, Scopus, and Embase) to identify relevant studies before 10th June 2023. The search identified 182 potential studies, from which 39 full-text articles were screened for relevance. Five articles with case-control design (n = 4,322, intervention group: 1714; control group: 2608) met the study inclusion criteria. The exposure variable was DII, with studies using two distinct models: quartile-based comparisons of DII and assessment of continuous DII. The meta-analysis of high versus low quartiles of DII with four effect sizes showed a significant association with MS/demyelinating autoimmune disease likelihood, with an odds ratio (OR) of 3.26 (95% confidence interval (CI) 1.16, 9.10). The meta-analysis of four studies with DII fit as a continuous variable showed a 31% increased likelihood of MS per unit increment; which was not statistically significant at the nominal alpha equals 0.05 (OR 1.31; 95% CI 0.95, 1.81). In conclusion, this systematic review and meta-analysis provides evidence of a positive association between higher DII scores with the likelihood of developing MS, highlighting that diet-induced inflammation could play a role in MS or other demyelinating autoimmune diseases risk.


Subject(s)
Diet , Inflammation , Multiple Sclerosis , Humans , Demyelinating Diseases , Autoimmune Diseases , Risk Factors
5.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(3): 487-494, 2024 Jun 18.
Article in Chinese | MEDLINE | ID: mdl-38864135

ABSTRACT

OBJECTIVE: To unveil the pathological changes associated with demyelination in schizophrenia (SZ) and its consequential impact on interstitial fluid (ISF) drainage, and to investigate the therapeutic efficacy of ursolic acid (UA) in treating demyelination and the ensuing abnormalities in ISF drainage in SZ. METHODS: Female C57BL/6J mice, aged 6-8 weeks and weighing (20±2) g, were randomly divided into three groups: control, SZ model, and UA treatment. The control group received intraperitoneal injection (ip) of physiological saline and intragastric administration (ig) of 1% carboxymethylcellulose sodium (CMC-Na). The SZ model group was subjected to ip injection of 2 mg/kg dizocilpine maleate (MK-801) and ig administration of 1% CMC-Na. The UA treatment group underwent ig administration of 25 mg/kg UA and ip injection of 2 mg/kg MK-801. The treatment group received UA pretreatment via ig administration for one week, followed by a two-week drug intervention for all the three groups. Behavioral assessments, including the open field test and prepulse inhibition experiment, were conducted post-modeling. Subsequently, changes in the ISF partition drainage were investigated through fluorescent tracer injection into specific brain regions. Immunofluorescence analysis was employed to examine alterations in aquaporin 4 (AQP4) polarity distribution in the brain and changes in protein expression. Myelin reflex imaging using Laser Scanning Confocal Microscopy (LSCM) was utilized to study modifications in myelin within the mouse brain. Quantitative data underwent one-way ANOVA, followed by TukeyHSD for post hoc pairwise comparisons between the groups. RESULTS: The open field test revealed a significantly longer total distance [(7 949.39±1 140.55) cm vs. (2 831.01±1 212.72) cm, P < 0.001] and increased central area duration [(88.43±22.06) s vs. (56.85±18.58) s, P=0.011] for the SZ model group compared with the controls. The UA treatment group exhibited signifi-cantly reduced total distance [(2 415.80±646.95) cm vs. (7 949.39±1 140.55) cm, P < 0.001] and increased central area duration [(54.78±11.66) s vs. (88.43±22.06) s, P=0.007] compared with the model group. Prepulse inhibition test results demonstrated a markedly lower inhibition rate of the startle reflex in the model group relative to the controls (P < 0.001 for both), with the treatment group displaying significant improvement (P < 0.001 for both). Myelin sheath analysis indicated significant demyelination in the model group, while UA treatment reversed this effect. Fluorescence tracing exhibited a significantly larger tracer diffusion area towards the rostral cortex and reflux area towards the caudal thalamus in the model group relative to the controls [(13.93±3.35) mm2 vs. (2.79±0.94) mm2, P < 0.001 for diffusion area; (2.48±0.38) mm2 vs. (0.05±0.12) mm2, P < 0.001 for reflux area], with significant impairment of drainage in brain regions. The treatment group demonstrated significantly reduced tracer diffusion and reflux areas [(7.93±2.48) mm2 vs. (13.93±3.35) mm2, P < 0.001 for diffusion area; (0.50±0.30) mm2 vs. (2.48±0.38) mm2, P < 0.001 for reflux area]. Immunofluorescence staining revealed disrupted AQP4 polarity distribution and reduced AQP4 protein expression in the model group compared with the controls [(3 663.88±733.77) µm2 vs. (13 354.92±4 054.05) µm2, P < 0.001]. The treatment group exhibited restored AQP4 polarity distribution and elevated AQP4 protein expression [(11 104.68±3 200.04) µm2 vs. (3 663.88±733.77) µm2, P < 0.001]. CONCLUSION: UA intervention ameliorates behavioral performance in SZ mice, Thus alleviating hyperactivity and anxiety symptoms and restoring sensorimotor gating function. The underlying mechanism may involve the improvement of demyelination and ISF drainage dysregulation in SZ mice.


Subject(s)
Demyelinating Diseases , Disease Models, Animal , Extracellular Fluid , Mice, Inbred C57BL , Schizophrenia , Triterpenes , Ursolic Acid , Animals , Mice , Triterpenes/therapeutic use , Triterpenes/pharmacology , Schizophrenia/drug therapy , Female , Demyelinating Diseases/drug therapy , Extracellular Fluid/drug effects , Extracellular Fluid/metabolism , Dizocilpine Maleate , Aquaporin 4/metabolism
6.
J Neuroinflammation ; 21(1): 157, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38879499

ABSTRACT

BACKGROUND: Cystatin F is a secreted lysosomal cysteine protease inhibitor that has been implicated in affecting the severity of demyelination and enhancing remyelination in pre-clinical models of immune-mediated demyelination. How cystatin F impacts neurologic disease severity following viral infection of the central nervous system (CNS) has not been well characterized and was the focus of this study. We used cystatin F null-mutant mice (Cst7-/-) with a well-established model of murine coronavirus-induced neurologic disease to evaluate the contributions of cystatin F in host defense, demyelination and remyelination. METHODS: Wildtype controls and Cst7-/- mice were intracranially (i.c.) infected with a sublethal dose of the neurotropic JHM strain of mouse hepatitis virus (JHMV), with disease progression and survival monitored daily. Viral plaque assays and qPCR were used to assess viral levels in CNS. Immune cell infiltration into the CNS and immune cell activation were determined by flow cytometry and 10X genomics chromium 3' single cell RNA sequencing (scRNA-seq). Spinal cord demyelination was determined by luxol fast blue (LFB) and Hematoxylin/Eosin (H&E) staining and axonal damage assessed by immunohistochemical staining for SMI-32. Remyelination was evaluated by electron microscopy (EM) and calculation of g-ratios. RESULTS: JHMV-infected Cst7-/- mice were able to control viral replication within the CNS, indicating that cystatin F is not essential for an effective Th1 anti-viral immune response. Infiltration of T cells into the spinal cords of JHMV-infected Cst7-/- mice was increased compared to infected controls, and this correlated with increased axonal damage and demyelination associated with impaired remyelination. Single-cell RNA-seq of CD45 + cells enriched from spinal cords of infected Cst7-/- and control mice revealed enhanced expression of transcripts encoding T cell chemoattractants, Cxcl9 and Cxcl10, combined with elevated expression of interferon-g (Ifng) and perforin (Prf1) transcripts in CD8 + T cells from Cst7-/- mice compared to controls. CONCLUSIONS: Cystatin F is not required for immune-mediated control of JHMV replication within the CNS. However, JHMV-infected Cst7-/- mice exhibited more severe clinical disease associated with increased demyelination and impaired remyelination. The increase in disease severity was associated with elevated expression of T cell chemoattractant chemokines, concurrent with increased neuroinflammation. These findings support the idea that cystatin F influences expression of proinflammatory gene expression impacting neuroinflammation, T cell activation and/or glia cell responses ultimately impacting neuroinflammation and neurologic disease.


Subject(s)
Coronavirus Infections , Cystatins , Demyelinating Diseases , Mice, Knockout , Murine hepatitis virus , Animals , Mice , Demyelinating Diseases/pathology , Demyelinating Diseases/metabolism , Demyelinating Diseases/virology , Demyelinating Diseases/immunology , Murine hepatitis virus/pathogenicity , Cystatins/genetics , Cystatins/metabolism , Coronavirus Infections/immunology , Coronavirus Infections/pathology , Mice, Inbred C57BL , Neuroinflammatory Diseases/immunology , Neuroinflammatory Diseases/pathology , Neuroinflammatory Diseases/metabolism
7.
Continuum (Minneap Minn) ; 30(3): 781-817, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38830071

ABSTRACT

OBJECTIVE: This article reviews the various conditions that can present with acute and severe central nervous system demyelination, the broad differential diagnosis of these conditions, the most appropriate diagnostic workup, and the acute treatment regimens to be administered to help achieve the best possible patient outcomes. LATEST DEVELOPMENTS: The discovery of anti-aquaporin 4 (AQP4) antibodies and anti-myelin oligodendrocyte glycoprotein (MOG) antibodies in the past two decades has revolutionized our understanding of acute demyelinating disorders, their evaluation, and their management. ESSENTIAL POINTS: Demyelinating disorders comprise a large category of neurologic disorders seen by practicing neurologists. In the majority of cases, patients with these conditions do not require care in an intensive care unit. However, certain disorders may cause severe demyelination that necessitates intensive care unit admission because of numerous simultaneous multifocal lesions, tumefactive lesions, or lesions in certain brain locations that lead to acute severe neurologic dysfunction. Intensive care may be necessary for the management and prevention of complications for patients who have severely altered mental status, rapidly progressive neurologic worsening, elevated intracranial pressure, severe cerebral edema, status epilepticus, or respiratory failure.


Subject(s)
Demyelinating Diseases , Adult , Female , Humans , Male , Middle Aged , Demyelinating Diseases/diagnosis , Demyelinating Diseases/therapy , Disease Management , Young Adult
8.
Neuromolecular Med ; 26(1): 22, 2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38824254

ABSTRACT

Stroke is a significant public health issue, and research has consistently focused on studying the mechanisms of injury and identifying new targets. As a CDK5 activator, p39 plays a crucial role in various diseases. In this article, we will explore the role and mechanism of p39 in cerebral ischemic injury. We measured the level of p39 using western blot and QPCR at various time points following cerebral ischemia-reperfusion (I/R) injury. The results indicated a significant reduction in the level of p39. TTC staining and behavioral results indicate that the knockout of p39 (p39KO) provides neuroprotection in the short-term. Interestingly, the behavioral dysfunction in p39KO mice was exacerbated after the repair phase of I/R. Further study revealed that this deterioration may be due to demyelination induced by elevated p35 levels. In summary, our study offers profound insights into the significance of p39 in both the acute and repair stages of ischemic injury recovery and a theoretical foundation for future therapeutic drug exploration.


Subject(s)
Mice, Inbred C57BL , Mice, Knockout , Myelin Sheath , Reperfusion Injury , Animals , Male , Mice , Brain Ischemia/genetics , Brain Ischemia/metabolism , Demyelinating Diseases/pathology , Demyelinating Diseases/genetics , Infarction, Middle Cerebral Artery/pathology , Phosphotransferases , Reperfusion Injury/metabolism , Reperfusion Injury/pathology
10.
Lipids Health Dis ; 23(1): 194, 2024 Jun 22.
Article in English | MEDLINE | ID: mdl-38909243

ABSTRACT

BACKGROUND: Lipid droplet (LD)-laden microglia is a key pathological hallmark of multiple sclerosis. The recent discovery of this novel microglial subtype, lipid-droplet-accumulating microglia (LDAM), is notable for increased inflammatory factor secretion and diminished phagocytic capability. Lipophagy, the autophagy-mediated selective degradation of LDs, plays a critical role in this context. This study investigated the involvement of microRNAs (miRNAs) in lipophagy during demyelinating diseases, assessed their capacity to modulate LDAM subtypes, and elucidated the potential underlying mechanisms involved. METHODS: C57BL/6 mice were used for in vivo experiments. Two weeks post demyelination induction at cervical level 4 (C4), histological assessments and confocal imaging were performed to examine LD accumulation in microglia within the lesion site. Autophagic changes were observed using transmission electron microscopy. miRNA and mRNA multi-omics analyses identified differentially expressed miRNAs and mRNAs under demyelinating conditions and the related autophagy target genes. The role of miR-223 in lipophagy under these conditions was specifically explored. In vitro studies, including miR-223 upregulation in BV2 cells via lentiviral infection, validated the bioinformatics findings. Immunofluorescence staining was used to measure LD accumulation, autophagy levels, target gene expression, and inflammatory mediator levels to elucidate the mechanisms of action of miR-223 in LDAM. RESULTS: Oil Red O staining and confocal imaging revealed substantial LD accumulation in the demyelinated spinal cord. Transmission electron microscopy revealed increased numbers of autophagic vacuoles at the injury site. Multi-omics analysis revealed miR-223 as a crucial regulatory gene in lipophagy during demyelination. It was identified that cathepsin B (CTSB) targets miR-223 in autophagy to integrate miRNA, mRNA, and autophagy gene databases. In vitro, miR-223 upregulation suppressed CTSB expression in BV2 cells, augmented autophagy, alleviated LD accumulation, and decreased the expression of the inflammatory mediator IL-1ß. CONCLUSION: These findings indicate that miR-223 plays a pivotal role in lipophagy under demyelinating conditions. By inhibiting CTSB, miR-223 promotes selective LD degradation, thereby reducing the lipid burden and inflammatory phenotype in LDAM. This study broadens the understanding of the molecular mechanisms of lipophagy and proposes lipophagy induction as a potential therapeutic approach to mitigate inflammatory responses in demyelinating diseases.


Subject(s)
Autophagy , Cathepsin B , Demyelinating Diseases , Lipid Droplets , Lysophosphatidylcholines , Mice, Inbred C57BL , MicroRNAs , Microglia , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Microglia/metabolism , Microglia/pathology , Mice , Lipid Droplets/metabolism , Demyelinating Diseases/metabolism , Demyelinating Diseases/chemically induced , Demyelinating Diseases/genetics , Demyelinating Diseases/pathology , Cathepsin B/metabolism , Cathepsin B/genetics , Lysophosphatidylcholines/metabolism , Disease Models, Animal , Male , Gene Expression Regulation , Cell Line
11.
Neuroimaging Clin N Am ; 34(3): 335-357, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38942520

ABSTRACT

In recent decades, advances in neuroimaging have profoundly transformed our comprehension of central nervous system demyelinating diseases. Remarkable technological progress has enabled the integration of cutting-edge acquisition and postprocessing techniques, proving instrumental in characterizing subtle focal changes, diffuse microstructural alterations, and macroscopic pathologic processes. This review delves into state-of-the-art modalities applied to multiple sclerosis, neuromyelitis optica spectrum disorders, and myelin oligodendrocyte glycoprotein antibody-associated disease. Furthermore, it explores how this dynamic landscape holds significant promise for the development of effective and personalized clinical management strategies, encompassing support for differential diagnosis, prognosis, monitoring treatment response, and patient stratification.


Subject(s)
Brain , Neuroimaging , Humans , Neuroimaging/methods , Brain/diagnostic imaging , Demyelinating Diseases/diagnostic imaging , Neuromyelitis Optica/diagnostic imaging , Magnetic Resonance Imaging/methods , Multiple Sclerosis/diagnostic imaging
12.
Neuroimaging Clin N Am ; 34(3): 421-438, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38942525

ABSTRACT

Atypical demyelinating lesions (ADLs) can be idiopathic, occurring as isolated and self-limited events, or can appear in different stages of relapsing demyelinating diseases. Not infrequently, ADLs occur in inflammatory syndromes associated with exogenous or endogenous toxic factors, metabolic imbalance, or infectious agents. It is important to recognize imaging patterns that indicate an inflammatory/demyelinating substrate in central nervous system lesions and to investigate potential triggers or complicating factors that might be associated. The prognostic and treatment strategies of ADLs are influenced by the underlying etiopathogenesis.


Subject(s)
Brain , Demyelinating Diseases , Magnetic Resonance Imaging , Humans , Demyelinating Diseases/diagnostic imaging , Magnetic Resonance Imaging/methods , Brain/diagnostic imaging
13.
Neuroimaging Clin N Am ; 34(3): 317-334, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38942519

ABSTRACT

Standardized MR imaging protocols are important for the diagnosis and monitoring of patients with multiple sclerosis (MS) and the appropriate use of MR imaging in routine clinical practice. Advances in using MR imaging to establish an earlier diagnosis of MS, safety concerns regarding intravenous gadolinium-based contrast agents, and the value of spinal cord MR imaging for diagnostic, prognostic, and monitoring purposes suggest a changing role of MR imaging for the management and care of MS patients. The MR imaging protocol emphasizes 3 dimensional acquisitions for optimal comparison over time.


Subject(s)
Demyelinating Diseases , Magnetic Resonance Imaging , Humans , Magnetic Resonance Imaging/methods , Magnetic Resonance Imaging/standards , Demyelinating Diseases/diagnostic imaging , Multiple Sclerosis/diagnostic imaging , Brain/diagnostic imaging , Spinal Cord/diagnostic imaging , Spinal Cord/pathology , Contrast Media
16.
Sci Rep ; 14(1): 13988, 2024 06 18.
Article in English | MEDLINE | ID: mdl-38886527

ABSTRACT

Demyelination is generated in several nervous system illnesses. Developing strategies for effective clinical treatments requires the discovery of promyelinating drugs. Increased GABAergic signaling through γ-aminobutyric acid type A receptor (GABAAR) activation in oligodendrocytes has been proposed as a promyelinating condition. GABAAR expressed in oligodendroglia is strongly potentiated by n-butyl-ß-carboline-3-carboxylate (ß-CCB) compared to that in neurons. Here, mice were subjected to 0.3% cuprizone (CPZ) added in the food to induce central nervous system demyelination, a well-known model for multiple sclerosis. Then ß-CCB (1 mg/Kg) was systemically administered to analyze the remyelination status in white and gray matter areas. Myelin content was evaluated using Black-Gold II (BGII) staining, immunofluorescence (IF), and magnetic resonance imaging (MRI). Evidence indicates that ß-CCB treatment of CPZ-demyelinated animals promoted remyelination in several white matter structures, such as the fimbria, corpus callosum, internal capsule, and cerebellar peduncles. Moreover, using IF, it was observed that CPZ intake induced an increase in NG2+ and a decrease in CC1+ cell populations, alterations that were importantly retrieved by ß-CCB treatment. Thus, the promyelinating character of ß-CCB was confirmed in a generalized demyelination model, strengthening the idea that it has clinical potential as a therapeutic drug.


Subject(s)
Carbolines , Cuprizone , Demyelinating Diseases , Disease Models, Animal , Remyelination , Animals , Cuprizone/toxicity , Remyelination/drug effects , Mice , Demyelinating Diseases/chemically induced , Demyelinating Diseases/pathology , Demyelinating Diseases/metabolism , Carbolines/pharmacology , Carbolines/administration & dosage , Myelin Sheath/metabolism , Myelin Sheath/drug effects , Male , Mice, Inbred C57BL , Oligodendroglia/drug effects , Oligodendroglia/metabolism , Multiple Sclerosis/drug therapy , Multiple Sclerosis/metabolism , Multiple Sclerosis/chemically induced , Multiple Sclerosis/pathology , White Matter/drug effects , White Matter/metabolism , White Matter/pathology , Magnetic Resonance Imaging
17.
Int J Biol Macromol ; 269(Pt 2): 131964, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38692525

ABSTRACT

This study aims to identify FDA-approved drugs that can target the kappa-opioid receptor (KOR) for the treatment of demyelinating diseases. Demyelinating diseases are characterized by myelin sheath destruction or formation that results in severe neurological dysfunction. Remission of this disease is largely dependent on the differentiation of oligodendrocyte precursor cells (OPCs) into mature oligodendrocytes (OLGs) in demyelinating lesions. KOR is an important regulatory protein and drug target for the treatment of demyelinating diseases. However, no drug targeting KOR has been developed due to the long clinical trials for drug discovery. Here, a structure-based virtual screening was applied to identify drugs targeting KOR among 1843 drugs of FDA-approved drug libraries, and famotidine was screen out by its high affinity cooperation with KOR as well as the clinical safety. We discovered that famotidine directly promoted OPC maturation and remyelination using the complementary in vitro and in vivo models. Administration of famotidine was not only effectively enhanced CNS myelinogenesis, but also promoted remyelination. Mechanically speaking, famotidine promoted myelinogenesis or remyelination through KOR/STAT3 signaling pathway. In general, our study provided evidence of new clinical applicability of famotidine for the treatment of demyelinating diseases for which there is currently no effective therapy.


Subject(s)
Cell Differentiation , Famotidine , Receptors, Opioid, kappa , Remyelination , STAT3 Transcription Factor , Signal Transduction , Animals , Humans , Mice , Cell Differentiation/drug effects , Central Nervous System/drug effects , Central Nervous System/metabolism , Demyelinating Diseases/drug therapy , Demyelinating Diseases/metabolism , Famotidine/pharmacology , Myelin Sheath/metabolism , Myelin Sheath/drug effects , Oligodendrocyte Precursor Cells/drug effects , Oligodendrocyte Precursor Cells/metabolism , Oligodendrocyte Precursor Cells/cytology , Oligodendroglia/drug effects , Oligodendroglia/metabolism , Oligodendroglia/cytology , Receptors, Opioid, kappa/metabolism , Remyelination/drug effects , Signal Transduction/drug effects , STAT3 Transcription Factor/metabolism , Female , Mice, Inbred C57BL , HEK293 Cells
18.
Mol Cell Neurosci ; 129: 103937, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38796120

ABSTRACT

Experimental models of multiple sclerosis (MS) have significantly contributed to our understanding of pathophysiology and the development of therapeutic interventions. Various in vivo animal models have successfully replicated key features of MS and associated pathophysiological processes, shedding light on the sequence of events leading to disease initiation, progression, and resolution. Nevertheless, these models often entail substantial costs and prolonged treatment periods. In contrast, in vitro models offer distinct advantages, including cost-effectiveness and precise control over experimental conditions, thereby facilitating more reproducible results. We have developed a novel in vitro model tailored to the study of oligodendroglial maturation and myelin deposition under demyelinating and remyelinating conditions, which encompasses all the cell types present in the central nervous system (CNS). Of note, our model enables the evaluation of microglial cell commitment through a protocol involving their depletion and subsequent repopulation. Given that the development and survival of microglia are critically reliant on colony-stimulating factor-1 receptor (CSF-1R) signaling, we have employed CSF-1R inhibition to effectively deplete microglia. This versatile model holds promise for the assessment of potential therapies aimed at promoting oligodendroglial differentiation to safeguard and repair myelin, hence mitigate neurodegenerative processes.


Subject(s)
Microglia , Myelin Sheath , Oligodendroglia , Remyelination , Microglia/metabolism , Animals , Oligodendroglia/metabolism , Myelin Sheath/metabolism , Mice , Remyelination/physiology , Demyelinating Diseases/metabolism , Demyelinating Diseases/pathology , Cell Differentiation/physiology , Cells, Cultured
19.
Immunity ; 57(6): 1394-1412.e8, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38821054

ABSTRACT

Recent single-cell RNA sequencing studies have revealed distinct microglial states in development and disease. These include proliferative-region-associated microglia (PAMs) in developing white matter and disease-associated microglia (DAMs) prevalent in various neurodegenerative conditions. PAMs and DAMs share a similar core gene signature. However, the extent of the dynamism and plasticity of these microglial states, as well as their functional significance, remains elusive, partly due to the lack of specific tools. Here, we generated an inducible Cre driver line, Clec7a-CreERT2, that targets PAMs and DAMs in the brain parenchyma. Utilizing this tool, we profiled labeled cells during development and in several disease models, uncovering convergence and context-dependent differences in PAM and DAM gene expression. Through long-term tracking, we demonstrated microglial state plasticity. Lastly, we specifically depleted DAMs in demyelination, revealing their roles in disease recovery. Together, we provide a versatile genetic tool to characterize microglial states in CNS development and disease.


Subject(s)
Cell Plasticity , Microglia , Remyelination , Microglia/physiology , Animals , Mice , Cell Plasticity/genetics , Demyelinating Diseases/genetics , Mice, Inbred C57BL , Mice, Transgenic , Disease Models, Animal , Brain , Myelin Sheath/metabolism , White Matter/pathology
20.
Mult Scler Relat Disord ; 87: 105627, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38704875

ABSTRACT

BACKGROUND: Demyelinating disorders of the CNS are a set of chronic, inflammatory, autoimmune conditions. To improve understanding of epidemiology, population characteristics and disease behaviour, an Indian, hospital-based registry has been established to serve as a platform for fostering collaborative research. The following article outlines the development, governance and current status of the Indian Multiple Sclerosis and Allied Demyelinating Disorders Registry and Research Network (IMSRN), the country's first scientific database and dedicated expert research network of these disorders. METHODS: Multiple reviews and stakeholder meetings were held to set up the registry. The IMSRN was formally initiated in August 2021 across 26 tertiary care centres. The registry is governed by the Indian Council of Medical Research (ICMR), New Delhi and its task force committee. The online secure database captures detailed clinical and imaging patient details at baseline and periodic follow up. Periodic meetings of the task force and collaborators are held to discuss the progress, improvements and research proposals. RESULTS: The IMSRN is currently active and recruiting patients following an informed consent. As of current, more than 3336 patients including RIS (N = 8), CIS (N = 134), MS (N = 1674), NMOSD (N= 561), MOGAD (N = 404), ADEM (N = 46), CRION (N = 21), CLIPPERS (N = 2), and GFAP (N =1) have been enrolled. 340 patients, not meeting the diagnostic criteria for any of the aforementioned disease phenotypes are in the others category. Various research proposals are being developed to study different aspects of these disorders. CONCLUSION: The IMSRN has been established with a vision to strengthen our understanding about MS, NMOSD, MOGAD, and other demyelinating disorders. This would help answer important questions related to disease profiles and long-term outcomes of patients in the Indian setting. From the standpoint of clinical practice, therapeutics, patient management, research, and national policy building, IMSRN shall serve as a synergising platform for bridging the gap in the aforementioned areas and guiding future research through national and international collaboration.


Subject(s)
Multiple Sclerosis , Registries , Humans , Multiple Sclerosis/epidemiology , Multiple Sclerosis/therapy , Multiple Sclerosis/diagnosis , India/epidemiology , Databases, Factual , Biomedical Research , Demyelinating Autoimmune Diseases, CNS/epidemiology , Adult , Demyelinating Diseases/epidemiology
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