Multiple sclerosis and myelin basic protein: insights into protein disorder and disease

Brain Expression Levels of Commonly Measured Blood Biomarkers of Neurological Damage Differ with Respect to Sex, Race, and Age

It is increasingly evident that blood biomarkers have potential to improve the diagnosis and management of both acute and chronic neurological conditions. The most well-studied candidates, and arguably those with the broadest utility, are proteins that are highly enriched in neural tissues and released into circulation upon cellular damage. It is currently unknown how the brain expression levels of these proteins is influenced by demographic factors such as sex, race, and age. Given that source tissue abundance is likely a key determinant of the levels observed in the blood during neurological pathology, understanding such influences is important in terms of identifying potential clinical scenarios that could produce diagnostic bias. In this study, we leveraged existing mRNA sequencing data originating from 2,642 normal brain specimens harvested from 382 human donors to examine potential demographic variability in the expression levels of genes which code for 28 candidate blood biomarkers of neurological damage. Existing mass spectrometry data originating from 26 additional normal brain specimens harvested from 26 separate human donors was subsequently used to tentatively assess whether observed transcriptional variance was likely to produce corresponding variance in terms of protein abundance. Genes associated with several well-studied or emerging candidate biomarkers including neurofilament light chain (NfL), ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCH-L1), neuron-specific enolase (NSE), and synaptosomal-associated protein 25 (SNAP-25) exhibited significant differences in expression with respect to sex, race, and age. In many instances, these differences in brain expression align well with and provide a mechanistic explanation for previously reported differences in blood levels.

Combined Central and Peripheral Demyelination (CCPD) Associated with MOG Antibodies: Report of Four New Cases and Narrative Review of the Literature

Background/Objectives: Myelin oligodendrocyte glycoprotein (MOG) is exclusively expressed in the central nervous system (CNS) and is found on the outer surface of oligodendrocytes. Antibodies to MOG are associated with CNS demyelination, whereas peripheral nervous system (PNS) demyelination is seldom reported to be related to MOG-IgG. Methods: The database of patients seen in our neurological academic center was searched for MOG-IgG seropositivity and concomitant demyelinating polyneuropathy. For the purpose of the review, in March 2024, we searched for case reports and case series in the following databases: PubMed, Scopus, Cochrane, and ScienceDirect. Inclusion criteria were MOG-IgG seropositivity and demyelinating polyneuropathy. Exclusion criteria were type of publication other than case reports and case series, unconfirmed diagnosis of demyelinating polyneuropathy, and other diseases causing demyelination in either the CNS or PNS. Critical appraisal of the selected case reports and case series was realized by JBI. Results: Four new cases were identified with MOG-IgG and confirmed demyelinating polyneuropathy. This review identified 22 cases that have been published since 2018. Clinical, imaging, neurophysiological, and immunological characteristics, as well as treatment options and outcomes are presented and compared to those of other cases with combined central and peripheral demyelination (CCPD). Conclusions: The pathogenetic mechanism is unclear; thus, different hypotheses are discussed. New case reporting and large cohort studies will help further the exploration of the underlying mechanism and guide more effective therapeutic interventions.

Serum mir-142-3p release in children with viral encephalitis and its relationship with nerve injury and inflammatory response

BACKGROUND

Viral encephalitis (VE) is a common infectious disease of the central nervous system in children. Children with severe disease may have progressive neurological damage and even lead to death.

AIMS

To assess the serum miR-142-3p levels in children with VE and the correlation between miR-142-3p and the severity and prognosis of VE. Besides, its relationship with nerve injury and inflammatory response was assessed.

METHODS

Children with VE were regarded as a case group and healthy children served as control. The content of serum miR-142-3p was determined using real-time quantitative PCR. The risk factors associated with severity and prognosis of cases were evaluated using logistic analysis. The discrepancy in miR-142-3p levels, nerve injury-related indicators, and inflammatory cytokines were contrasted among groups. The ROC curve was conducted to assess the diagnostic performance of serum miR-142-3p in predicting prognosis of children with VE.

RESULTS

The altered expression of miR-142-3p in serum of children with VE was enhanced in contrast to healthy control. Serum nerve injury indicators MBP, β-EP, and NSE levels and serum inflammatory cytokines IL-6, IL-18, and IFN-γ were high in children with VE in contrast to healthy control, and had positive relevance with serum miR-142-3p. Besides, serum miR-142-3p was a risk factor associated with the severity and prognosis of children with VE. Serum miR-142-3p had diagnostic performance in predicting the prognosis of children with VE.

CONCLUSION

Serum miR-142-3p content is high in children with VE and maybe a diagnosis marker for predicting prognosis. The specific miR-142-3p expression may be directly related to the severity of nerve injury and inflammatory response for VE.

Purmorphamine, a Smo-Shh/Gli Activator, Promotes Sonic Hedgehog-Mediated Neurogenesis and Restores Behavioural and Neurochemical Deficits in Experimental Model of Multiple Sclerosis

Multiple sclerosis (MS) is a pathological condition characterized by the demyelination of nerve fibers, primarily attributed to the destruction of oligodendrocytes and subsequent motor neuron impairment. Ethidium bromide (EB) is a neurotoxic compound that induces neuronal degeneration, resulting in demyelination and symptoms resembling those observed in experimental animal models of multiple sclerosis (MS). The neurotoxic effects induced by EB in multiple sclerosis (MS) are distinguished by the death of oligodendrocytes, degradation of myelin basic protein (MBP), and deterioration of axons. Neurological complications related to MS have been linked to alterations in the signaling pathway known as smo-shh. Purmorphine (PUR) is a semi-synthetic compound that exhibits potent Smo-shh agonistic activity. It possesses various pharmacological properties, including antioxidant, anti-inflammatory, anti-apoptotic, and neuromodulatory effects. Hence, the current investigation was conducted to assess the neuroprotective efficacy of PUR (at doses of 5 and 10 mg/kg, administered intraperitoneally) both individually and in conjunction with Fingolimod (FING) (at a dose of 0.5 mg/kg, administered intraperitoneally) in the experimental model of MS induced by EB. The administration of EB was conducted via the intracerebropeduncle route (ICP) over a period of seven days in the brain of rats. The Wistar rats were allocated into six groups using randomization, each consisting of eight rats (n = 8 per group). The experimental groups in this study were categorized as follows: (I) Sham Control, (II) Vehicle Control, (III) PUR per se, (IV) EB, (V) EB + PUR5, (VI) EB + PUR10, (VII) EB + FING 0.5, and (VIII) EB + PUR10 + FING 0.5. On the final day of the experimental timeline, all animal subjects were euthanized, and subsequent neurochemical estimations were conducted on cerebrospinal fluid, blood plasma, and brain tissue samples. In addition, we conducted neurofilament (NFL) analysis and histopathological examination. We utilized the luxol myelin stain to understand better the degeneration associated with MS and its associated neurological complications. The findings of our study indicate that the activation of SMO-Shh by PUR has a mitigating effect on neurobehavioral impairments induced by EB, as well as a restorative effect on cellular and neurotransmitter abnormalities in an experimental model of MS.

Immunopathogenesis of multiple sclerosis: molecular and cellular mechanisms and new immunotherapeutic approaches

BACKGROUND

Multiple sclerosis (MS) is a central nervous system (CNS) demyelinating autoimmune disease with increasing global prevalence. It predominantly affects females, especially those of European descent. The interplay between environmental factors and genetic predisposition plays a crucial role in MS etiopathogenesis.

METHODS

We searched recent relevant literature on reputable databases, which include, PubMed, Embase, Web of Science, Scopus, and ScienceDirect using the following keywords: multiple sclerosis, pathogenesis, autoimmunity, demyelination, therapy, and immunotherapy.

RESULTS

Various animal models have been employed to investigate the MS etiopathogenesis and therapeutics. Autoreactive T cells within the CNS recruit myeloid cells through chemokine expression, leading to the secretion of inflammatory cytokines driving the MS pathogenesis, resulting in demyelination, gliosis, and axonal loss. Key players include T cell lymphocytes (CD4+ and CD8+), B cells, and neutrophils. Signaling dysregulation in inflammatory pathways and the immunogenetic basis of MS are essential considerations for any successful therapy to MS. Data indicates that B cells and neutrophils also have significant roles in MS, despite the common belief that T cells are essential. High neutrophil-to-lymphocyte ratios correlate with MS severity, indicating their contribution to disease progression. Dysregulated signaling pathways further exacerbate MS progression.

CONCLUSION

MS remains incurable, but disease-modifying therapies, monoclonal antibodies, and immunomodulatory drugs offer hope for patients. Research on the immunogenetics and immunoregulatory functions of gut microbiota is continuing to provide light on possible treatment avenues. Understanding the complex interplay between genetic predisposition, environmental factors, and immune dysregulation is critical for developing effective treatments for MS.

Neurological features of Hansen disease: a retrospective, multicenter cohort study

To elucidate the neurological features of Hansen disease. The medical records of patients with confirmed Hansen disease transferred from the neurology department were reviewed, and all medical and neurological manifestations of Hansen disease were assessed. Eleven patients with confirmed Hansen disease, 10 with newly detected Hansen disease and 1 with relapsed Hansen disease, who visited neurology departments were enrolled. The newly detected patients with Hansen disease were classified as having lepromatous leprosy (LL, n = 1), borderline lepromatous leprosy (BL, n = 2), borderline leprosy (BB, n = 2), borderline tuberculoid leprosy (BT, n = 1), tuberculoid leprosy (TT, n = 2), or pure neural leprosy (PNL, n = 2). All of the patients with confirmed Hansen were diagnosed with peripheral neuropathy (100.00%, 11/11). The symptoms and signs presented were mainly limb numbness (100.00%, 11/11), sensory and motor dysfunction (100.00%, 11/11), decreased muscle strength (90.90%, 10/11), and skin lesions (81.81%, 9/11). Nerve morphological features in nerve ultrasonography (US) included peripheral nerve asymmetry and segmental thickening (100.00%, 9/9). For neuro-electrophysiology feature, the frequency of no response of sensory nerves was significantly higher than those of motor nerves [(51.21% 42/82) vs (24.70%, 21/85)(P = 0.0183*)] by electrodiagnostic (EDX) studies. Nerve histological features in nerve biopsy analysis included demyelination (100.00%, 5/5) and axonal damage (60.00%, 3/5). In addition to confirmed diagnoses by acid-fast bacteria (AFB) staining (54.54%, 6/11) and skin pathology analysis (100.00%, 8/8), serology and molecular technology were positive in 36.36% (4/11) and 100.00% (11/11) of confirmed patients of Hansen disease, respectively. It is not uncommon for patients of Hansen disease to visit neurology departments due to peripheral neuropathy. The main pathological features of affected nerves are demyelination and axonal damage. The combination of nerve US, EDX studies, nerve biopsy, and serological and molecular tests can improve the diagnosis of Hansen disease.

Acrylamide, Applied During Pregnancy and Postpartum Period in Offspring Rats, Significantly Disrupted Myelination by Decreasing the Levels of Myelin-Related Proteins: MBP, MAG, and MOG

Acrylamide (ACR) is a colorless, odorless, and water-soluble solid molecule. In addition to being an important industrial material, ACR is found in fried and baked carbohydrate-rich foods. ACR is regarded as a typical axonal neurotoxin that induces neuropathy. The brain is protected from oxidative damage by vitamin E, which is regarded as the most powerful fat-soluble antioxidant vitamin. This study aimed to reveal the toxic effect of ACR on the development of myelin in the brain at the molecular level and to examine whether Vitamin E has a neuroprotective effect on the harmful effect of ACR. The study was started by dividing 40 pregnant rats into 4 groups and after lactation, the study was continued with offspring rats (females and males offspring rats) from each group. Offspring rats were equally divided into Control, Vitamin E, ACR, ACR + Vitamin E groups. Following the ACR administration, the Water Maze test was applied to evaluate cognitive function. To evaluate the level of demyelination and remyelination, MBP, MAG, and MOG proteins and mRNA levels were performed. In addition, the degeneration of myelin and glial cells was examined by immunohistochemistry and electron microscopic analysis. Analysis results showed that ACR administration decreased gene and protein levels of myelin-related proteins MBP, MAG, and MOG. The findings were confirmed by histopathological, immunohistochemical, and microscopic examinations. The application of vitamin E improved this negative effect of ACR. It has been observed that ACR may play a role in the pathogenesis of myelin-related neurodegenerative diseases by causing demyelination during gestation, lactation, and post-lactation. In addition, it has been understood that vitamin E supports myelination as a strong neuroprotective vitamin against the toxicity caused by ACR. Our research results suggest that acrylamide may play a role in the etiopathogenesis of demyelinating diseases such as multiple sclerosis in humans since fast-food-type nutrition is very common today and people are chronically exposed to acrylamide.

Recent Advances in Biosensors for Diagnosis of Autoimmune Diseases

Over the last decade, autoimmune diseases (ADs) have undergone a significant increase because of genetic and/or environmental factors; therefore, their simple and fast diagnosis is of high importance. The conventional diagnostic techniques for ADs require tedious sample preparation, sophisticated instruments, a dedicated laboratory, and qualified personnel. For these reasons, biosensors could represent a useful alternative to these methods. Biosensors are considered to be promising tools that can be used in clinical analysis for an early diagnosis due to their high sensitivity, simplicity, low cost, possible miniaturization (POCT), and potential ability for real-time analysis. In this review, recently developed biosensors for the detection of autoimmune disease biomarkers are discussed. In the first part, we focus on the main AD biomarkers and the current methods of their detection. Then, we discuss the principles and different types of biosensors. Finally, we overview the characteristics of biosensors based on different bioreceptors reported in the literature.

Combined laser-activated SVF and PRP remodeled spinal sclerosis via activation of Olig-2, MBP, and neurotrophic factors and inhibition of BAX and GFAP

A single injection of platelet-rich plasma (PRP) or stromal vascular fraction (SVF) in treating neurological ailments suggests promise; however, there is limited evidence of the efficacy of combination therapy. This trial aimed to determine whether combining SVF and PRP could provide further therapeutic effects in treating multiple sclerosis (MS). Fifteen Persian cats were separated into three groups (n = 5): group I (control negative), and group II (control positive); EB was injected intrathecally into the spinal cord and then treated 14 days later with intrathecal phosphate buffered saline injection, and group III (SVF + PRP), cats were injected intrathecally with EB through the spinal cord, followed by a combination of SVF and PRP 14 days after induction. Therapeutic effects were evaluated using the Basso-Beattie-Bresnahan scale throughout the treatment timeline and at the end. Together with morphological, MRI scan, immunohistochemical, transmission electron microscopy, and gene expression investigations. The results demonstrated that combining SVF and PRP successfully reduced lesion intensity on gross inspection and MRI. In addition to increased immunoreactivity to Olig2 and MBP and decreased immunoreactivity to Bax and GFAP, there was a significant improvement in BBB scores and an increase in neurotrophic factor (BDNF, NGF, and SDF) expression when compared to the positive control group. Finally, intrathecal SVF + PRP is the most promising and safe therapy for multiple sclerosis, resulting in clinical advantages such as functional recovery, MRI enhancement, and axonal remyelination.

Myelin basic proteins charge isomers interact differently with the peptidyl arginine deiminase-2

The deamination of arginine and its conversion to citrulline is a modification observed in positively charged proteins such as histones or myelin basic protein (MBP). This reaction is catalyzed by peptidyl arginine deiminase (PAD), whose abnormal activation is associated with autoimmune diseases like rheumatoid arthritis and multiple sclerosis. However, the mechanisms that trigger PAD activation and the pathophysiological processes involved in hypercitrullination remain unknown. In this study, we investigated the interaction between PAD and various charged isomers of MBP, each differing in the degree of post-translational modification. Immunoprecipitation experiments were conducted to examine the binding between PAD and the different charge isomers of MBP. Our findings revealed that the phosphorylated forms of MBP (C3 and C4) exhibited a higher affinity for PAD compared to the unmodified (C1) and fully citrullinated forms (C8). Additionally, we observed that only in the presence of the unmodified C1 isomer did PAD undergo autocitrullination, which was inhibited by the endogenous guanidine-containing component, creatine. In the presence of other isomers, PAD did not undergo autocitrullination. Furthermore, we found that the unmodified isomer of MBP-C1 contains methylated arginines, which were not affected by the pre-treatment with PAD. Based on our findings, we propose that the increased phosphorylation of central threonines in the original MBP may trigger PAD activation, leading to increased citrullination of the protein and subsequent disorganization of the myelin sheath. These insights contribute to a better understanding of the underlying mechanisms in autoimmune diseases associated with hypercitrullination, potentially opening new avenues for therapeutic interventions.

Understanding the link between neurotropic viruses, BBB permeability, and MS pathogenesis

Neurotropic viruses can infiltrate the CNS by crossing the blood-brain barrier (BBB) through various mechanisms including paracellular, transcellular, and "Trojan horse" mechanisms during leukocyte diapedesis. These viruses belong to several families, including retroviruses; human immunodeficiency virus type 1 (HIV-1), flaviviruses; Japanese encephalitis (JEV); and herpesviruses; herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV), and mouse adenovirus 1 (MAV-1). For entering the brain, viral proteins act upon the tight junctions (TJs) between the brain microvascular endothelial cells (BMECs). For instance, HIV-1 proteins, such as glycoprotein 120, Nef, Vpr, and Tat, disrupt the BBB and generate a neurotoxic effect. Recombinant-Tat triggers amendments in the BBB by decreasing expression of the TJ proteins such as claudin-1, claudin-5, and zona occludens-1 (ZO-1). Thus, the breaching of BBB has been reported in myriad of neurological diseases including multiple sclerosis (MS). Neurotropic viruses also exhibit molecular mimicry with several myelin sheath proteins, i.e., antibodies against EBV nuclear antigen 1 (EBNA1) aa411-426 cross-react with MBP and EBNA1 aa385-420 was found to be associated with MS risk haplotype HLA-DRB1*150. Notably, myelin protein epitopes (PLP139-151, MOG35-55, and MBP87-99) are being used to generate model systems for MS such as experimental autoimmune encephalomyelitis (EAE) to understand the disease mechanism and therapeutics. Viruses like Theiler's murine encephalomyelitis virus (TMEV) are also commonly used to generate EAE. Altogether, this review provide insights into the viruses' association with BBB leakiness and MS along with possible mechanistic details which could potentially use for therapeutics.

Phase-Dependent Adsorption of Myelin Basic Protein to Phosphatidylcholine Lipid Bilayers

The dense packing of opposite cytoplasmic surfaces of the lipid-enriched myelin membrane, responsible for the proper saltatory conduction of nerve impulses through axons, is ensured by the adhesive properties of myelin basic protein (MBP). Although preferentially interacting with negatively charged phosphatidylserine (PS) lipids, as an intrinsically disordered protein, it can easily adapt its shape to its immediate environment and thus adsorb to domains made of zwitterionic phosphatidylcholine (PC) lipids. As the molecular-level interaction pattern between MBP and PC lipid membranes suffers from scarce characterization, an experimental and computational study of multilamellar liposomes (MLVs) composed of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in the presence of bovine MBP is presented here. Calorimetric and temperature-dependent UV-Vis measurements identified DPPC pretransition temperature (Tp) and calorimetric enthalpy (ΔHcal) as the physicochemical parameters most responsive to the presence of MBP. Besides suggesting an increase in β-sheet fractions of structured MBP segments as DPPC lipids undergo from the gel (20 °C) to the fluid (50 °C) phase, FTIR spectra unraveled the significant contribution of lysine (Lys) residues in the adsorption pattern, especially when DPPC is in the fluid (50 °C) phase. In addition to highlighting the importance of Lys residues in the MBP adsorption on DPPC lipid bilayer, employing salt bridges (SBs) and hydrogen bonds (HBs), MD data suggest the crucial importance of the orientation of MBP with respect to the surface of the DPPC lipid bilayer.

Blood-brain barrier dysfunction in multiple sclerosis: causes, consequences, and potential effects of therapies

Established by brain endothelial cells, the blood-brain barrier (BBB) regulates the trafficking of molecules, restricts immune cell entry into the CNS, and has an active role in neurovascular coupling (the regulation of cerebral blood flow to support neuronal activity). In the early stages of multiple sclerosis, around the time of symptom onset, inflammatory BBB damage is accompanied by pathogenic immune cell infiltration into the CNS. In the later stages of multiple sclerosis, dysregulation of neurovascular coupling is associated with grey matter atrophy. Genetic and environmental factors associated with multiple sclerosis, including dietary habits, the gut microbiome, and vitamin D concentrations, might contribute directly and indirectly to brain endothelial cell dysfunction. Damage to brain endothelial cells leads to an influx of deleterious molecules into the CNS, accelerating leakage across the BBB. Potential future therapeutic approaches might help to prevent BBB damage (eg, monoclonal antibodies targeting cell adhesion molecules and fibrinogen) and help to repair BBB dysfunction (eg, mesenchymal stromal cells) in people with multiple sclerosis.

Inflammation as common link to progressive neurological diseases

Life expectancy has increased immensely over the past decades, bringing new challenges to the health systems as advanced age increases the predisposition for many diseases. One of those is the burden of neurologic disorders. While many hypotheses have been placed to explain aging mechanisms, it has been widely accepted that the increasing pro-inflammatory status with advanced age or "inflammaging" is a main determinant of biological aging. Furthermore, inflammaging is at the cornerstone of many age-related diseases and its involvement in neurologic disorders is an exciting hypothesis. Indeed, aging and neurologic disorders development in the elderly seem to share some basic pathways that fundamentally converge on inflammation. Peripheral inflammation significantly influences brain function and contributes to the development of neurological disorders, including Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Understanding the role of inflammation in the pathogenesis of progressive neurological diseases is of crucial importance for developing effective treatments and interventions that can slow down or prevent disease progression, therefore, decreasing its social and economic burden.

Active Induction of a Multiple Sclerosis-Like Disease in Common Laboratory Mouse Strains

Experimental autoimmune encephalomyelitis (EAE) is a neuroinflammatory disease with facets in common with multiple sclerosis (MS). It is induced in susceptible mammalian species, with rodents as the preferred hosts, and has been used for decades as a model to investigate the immunopathogenesis of MS as well as for preclinical evaluation of candidate MS therapeutics. Most commonly, EAE is generated by active immunization with central nervous system (CNS) antigens, such as whole CNS homogenate, myelin proteins, or peptides derived from these proteins. However, EAE actually represents a spectrum of diseases in which specific combinations of host/CNS antigen exhibit defined clinical profiles, each associated with unique immunological and pathological features. Similar to MS, EAE is a complex disease where development and progression are also modulated by environmental factors; therefore, the establishment of any given EAE variant can be challenging and requires careful optimization. Here, we describe protocols for three EAE variants, successfully generated in our laboratory, and provide additional information as to how to maintain their unique features and reproducibility.

Advances of Genome Editing with CRISPR/Cas9 in Neurodegeneration: The Right Path towards Therapy

The rate of neurodegenerative disorders (NDDs) is rising rapidly as the world's population ages. Conditions such as Alzheimer's disease (AD), Parkinson's disease (PD), and dementia are becoming more prevalent and are now the fourth leading cause of death, following heart disease, cancer, and stroke. Although modern diagnostic techniques for detecting NDDs are varied, scientists are continuously seeking new and improved methods to enable early and precise detection. In addition to that, the present treatment options are limited to symptomatic therapy, which is effective in reducing the progression of neurodegeneration but lacks the ability to target the root cause-progressive loss of neuronal functioning. As a result, medical researchers continue to explore new treatments for these conditions. Here, we present a comprehensive summary of the key features of NDDs and an overview of the underlying mechanisms of neuroimmune dysfunction. Additionally, we dive into the cutting-edge treatment options that gene therapy provides in the quest to treat these disorders.

Matrine mediated neuroprotective potential in experimental multiple sclerosis: Evidence from CSF, blood markers, brain samples and in-silico investigations

Multiple sclerosis (MS) is a debilitating, inflammatory, and demyelinating disease of the central nervous system influenced by environmental and genetic factors. Around 2.8 million people worldwide are affected by MS due to its challenging diagnosis and treatment. Our study investigates the role of the JAK/STAT and PPAR-gamma signaling pathways in the progression of multiple sclerosis. Inflammation and demyelination can be caused by dysregulation of these pathways. Modulating the STAT-3, mTOR, and PPAR-gamma signaling pathways may offer therapeutic potential for multiple sclerosis. Matrine (40 and 80 mg/kg, i.p.), a quinolizidine alkaloid derived from Sophora flavescens, has been investigated for its therapeutic potential in our laboratory. Matrine has been studied for its neuroprotective effect in neurodegenerative diseases. It inhibits inflammatory responses and promotes regeneration of damaged myelin sheaths, indicating its potential efficacy in treating multiple sclerosis. Matrine exerts its neuroprotective effect by inhibiting STAT-3 and mTOR and promoting PPAR-gamma expression.GW9662, a PPAR-gamma antagonist (2 mg/kg, i.p.), was administered to evaluate the involvement of PPAR-gamma and to compare the efficacy of matrine's potential neuroprotective effect. Matrine's interaction with the STAT-3, mTOR, and PPAR-gamma pathways in multiple Sclerosis was also validated and confirmed through insilico investigation. In addition, matrine altered the CBC profile, intensifying the clinical presentation of multiple sclerosis. In addition, we evaluated the diagnostic potential of various biological samples, including CSF, blood plasma, and brain homogenates (striatum, cortex, hippocampus, and midbrain). These samples were used to evaluate the neurochemical changes caused by neurobehavioral alterations during the progression of multiple sclerosis. These results indicate that matrine treatment ameliorated multiple sclerosis and that the mechanism underlying these effects may be closely related to the modulation of the STAT-3/mTOR/PPAR-gamma signaling pathway.

Structural dynamics of moonlighting intrinsically disordered proteins - A black box in multiple sclerosis

Multiple Sclerosis (MS) is a demyelinating disease of the central nervous system that disturbs the flow of brain signals to other parts of the body. The actual cause of the disease is still not apparent. The intrinsically disordered proteins (IDP) play a crucial role in neurodegenerative diseases like Alzheimer's, Lewy bodies, Parkinson's, Amyotrophic Lateral Sclerosis, Multiple Sclerosis, etc. In MS, it was known that the immune system attacks the proteins like Myelin Basic Protein (MBP), Myelin-associated Oligodendrocyte Basic protein (MOBP), Myelin-Associated Protein (MAG), and Myelin Proteolipid Protein (PLP) and this leads to demyelination causing MS. Here the proteins MBP and MOBP are both moonlighting intrinsically disordered proteins and exist between the myelin sheath, unlike MAG which is a transmembrane protein. The main focus of the article was to examine the significant role of proteins intrinsically disordered regions (IDR) in maintaining their function. Molecular dynamics simulation studies were performed to study the conformational dynamics of these protein IDRs both in water and near the myelin sheath. The results suggest that the IDR dominates the structural dynamics of these proteins and IDR in both proteins was responsible for their interaction with the myelin sheath. Interestingly, it was noted that the known epitopes MBP83-96 and MOBP65-87 in the IDR have no interaction with the myelin sheath. Thus when the protein remains intrinsically disordered it maintains the proper function and myelin integrity and if it adopts folds the region was identified as an epitope by the immune system leading to demyelination causing MS.

Use of 3D Printing Techniques to Fabricate Implantable Microelectrodes for Electrochemical Detection of Biomarkers in the Early Diagnosis of Cardiovascular and Neurodegenerative Diseases

This Review provides a comprehensive overview of 3D printing techniques to fabricate implantable microelectrodes for the electrochemical detection of biomarkers in the early diagnosis of cardiovascular and neurodegenerative diseases. Early diagnosis of these diseases is crucial to improving patient outcomes and reducing healthcare systems' burden. Biomarkers serve as measurable indicators of these diseases, and implantable microelectrodes offer a promising tool for their electrochemical detection. Here, we discuss various 3D printing techniques, including stereolithography (SLA), digital light processing (DLP), fused deposition modeling (FDM), selective laser sintering (SLS), and two-photon polymerization (2PP), highlighting their advantages and limitations in microelectrode fabrication. We also explore the materials used in constructing implantable microelectrodes, emphasizing their biocompatibility and biodegradation properties. The principles of electrochemical detection and the types of sensors utilized are examined, with a focus on their applications in detecting biomarkers for cardiovascular and neurodegenerative diseases. Finally, we address the current challenges and future perspectives in the field of 3D-printed implantable microelectrodes, emphasizing their potential for improving early diagnosis and personalized treatment strategies.

Evaluating Gene Expression and Methylation Profiles of TCF4, MBP, and EGR1 in Peripheral Blood of Drug-Free Patients with Schizophrenia: Correlations with Psychopathology, Intelligence, and Cognitive Impairment

Discovery and validation of new, reliable diagnostic and predictive biomarkers for schizophrenia (SCZ) are an ongoing effort. Here, we assessed the mRNA expression and DNA methylation of the TCF4, MBP, and EGR1 genes in the blood of patients with SCZ and evaluated their relationships to psychopathology and cognitive impairments. Quantitative real-time PCR and quantitative methylation-specific PCR methods were used to assess the expression level and promoter DNA methylation status of these genes in 70 drug-free SCZ patients and 72 healthy controls. The correlation of molecular changes with psychopathology and cognitive performance of participants was evaluated. We observed downregulation of TCF4 and upregulation of MBP mRNA levels in SCZ cases, relative to controls in our study. DNA methylation status at the promoter region of TCF4 demonstrated an altered pattern in SCZ as well. Additionally, TCF4 mRNA levels were inversely correlated with PANSS and Stroop total errors and positively correlated with WAIS total score and working memory, consistent with previous studies by our group. In contrast, MBP mRNA level was significantly positively correlated with PANSS and Stroop total errors and inversely correlated with WAIS total score and working memory. These epigenetic and expression signatures can help to assemble a peripheral biomarker-based diagnostic panel for SCZ.

Tehranolid and Artemisinin Effects on Ameliorating Experimental Autoimmune Encephalomyelitis by Modulating Inflammation and Remyelination

Multiple sclerosis (MS) is an autoimmune demyelinating disease of the central nervous system. Artemisinin (ART) is a natural sesquiterpene lactone with an endoperoxide bond that is well-known for its anti-inflammatory effects in experimental autoimmune encephalomyelitis (EAE), the most commonly used animal model of MS. Tehranolide (TEH) is a novel compound with structural similarity to ART. In this study, we aimed to investigate the ameliorating effect of TEH on EAE development by targeting proteins and genes involved in this process and compare its effects with ART. Female C57BL/6 mice were immunized with MOG35-55. Twelve days post-immunization, mice were treated with 0.28 mg/kg/day TEH and 2.8 mg/kg/day ART for 18 consecutive days, and the clinical score was measured daily. The levels of pro-inflammatory and anti-inflammatory cytokines were assessed in mice serum and splenocytes by ELISA. We also evaluated the mRNA expression level of cytokines, as well as genes involved in T cell differentiation and myelination in the spinal cord tissue by qRT-PCR. Administration of TEH and ART significantly alleviated EAE signs. A significant reduction in IL-6 and IL-17 secretion and IL-17 and IL-1 gene expression in spinal cord were observed in the TEH-treated group. ART had similar or less significant effects. Moreover, TGF-β, IL-4, and IL-10 genes were stimulated by ART and TEH in the spinal cord, while the treatments did not affect IFN-γ expression. Both treatments dramatically increased the expression of FOXP3, GATA3, MBP, and AXL. Additionally, the T-bet gene was reduced after TEH administration. The compounds made no changes in RORγt, nestin, Gas6, Tyro3, and Mertk mRNA expression levels in the spinal cord. The study revealed that both TEH and ART can effectively modulate the genes responsible for inflammation and myelination that play a crucial role in EAE. Interestingly, TEH demonstrated a greater potency compared to ART and hence may have the potential to be evaluated in interventions for the management of MS.

Single-Cell Spatial MIST for Versatile, Scalable Detection of Protein Markers

High-multiplex detection of protein biomarkers across tissue regions has been an attractive spatial biology approach due to significant advantages over traditional immunohistochemistry (IHC) methods. Different from most methods, spatial multiplex in situ tagging (MIST) transfers the spatial protein expression information to an ultrahigh-density, large-scale MIST array. This technique has been optimized to reach single-cell resolution by adoption of smaller array units and 30% 8-arm PEG polymer as transfer medium. Tissue cell nuclei stained with lamin B have been clearly visualized on the MIST arrays and are colocalized with detection of nine mouse brain markers. Pseudocells defined at 10 μm in size have been used to fully profile tissue regions including cells and the intercellular space. We showcased the versatility of our technology by successfully detecting 20 marker proteins in kidney samples with the addition of five minutes atop the duration of standard immunohistochemistry protocols. Spatial MIST is amenable to iterative staining and detection on the same tissue samples. When 25 proteins were co-detected on 1 mouse brain section for each round and 5 rounds were executed, an ultrahigh multiplexity of 125 proteins was obtained for each pseudocell. With its unique abilities, this single-cell spatial MIST technology has the potential to become an important method in advanced diagnosis of complex diseases.

Alterations of Oligodendrocyte and Myelin Energy Metabolism in Multiple Sclerosis

Multiple sclerosis (MS) is a complex autoimmune disease of the central nervous system (CNS), characterized by demyelination and neurodegeneration. Oligodendrocytes play a vital role in maintaining the integrity of myelin, the protective sheath around nerve fibres essential for efficient signal transmission. However, in MS, oligodendrocytes become dysfunctional, leading to myelin damage and axonal degeneration. Emerging evidence suggests that metabolic changes, including mitochondrial dysfunction and alterations in glucose and lipid metabolism, contribute significantly to the pathogenesis of MS. Mitochondrial dysfunction is observed in both immune cells and oligodendrocytes within the CNS of MS patients. Impaired mitochondrial function leads to energy deficits, affecting crucial processes such as impulse transmission and axonal transport, ultimately contributing to neurodegeneration. Moreover, mitochondrial dysfunction is linked to the generation of reactive oxygen species (ROS), exacerbating myelin damage and inflammation. Altered glucose metabolism affects the energy supply required for oligodendrocyte function and myelin synthesis. Dysregulated lipid metabolism results in changes to the composition of myelin, affecting its stability and integrity. Importantly, low levels of polyunsaturated fatty acids in MS are associated with upregulated lipid metabolism and enhanced glucose catabolism. Understanding the intricate relationship between these mechanisms is crucial for developing targeted therapies to preserve myelin and promote neurological recovery in individuals with MS. Addressing these metabolic aspects may offer new insights into potential therapeutic strategies to halt disease progression and improve the quality of life for MS patients.

Dual role of peripheral B cells in multiple sclerosis: emerging remote players in demyelination and novel diagnostic biomarkers

Introduction

Multiple sclerosis is an inflammatory and demyelinating disease caused by a pathogenic immune response against the myelin sheath surfaces of oligodendrocytes. The demyelination has been classically associated with pathogenic B cells residing in the central nervous system that release autoreactive antibodies against myelin. The aim of the present study was to investigate whether extracellular vesicles (EVs) mediate delivery of myelin autoreactive antibodies from peripheral B cells against oligodendrocytes in multiple sclerosis (MS) and to analyze whether these EVs could mediate demyelination in vitro. We also studied the role of these EV-derived myelin antibodies as a diagnostic biomarker in MS.

Methods

This is a prospective, observational, and single-center study that includes patients with MS and two control groups: patients with non-immune white matter lesions and healthy controls. We isolated B-cell-derived EVs from the blood and cerebrospinal fluid (CSF) and analyzed their myelin antibody content. We also studied whether antibody-loaded EVs reach oligodendrocytes in patients with MS and the effect on demyelination of B-cell-derived EVs containing antibodies in vitro.

Results

This study enrolled 136 MS patients, 23 white matter lesions controls, and 39 healthy controls. We found autoreactive myelin antibodies in EVs that were released by peripheral B cells, but not by populations of B cells resident in CSF. We also identified a cut-off of 3.95 ng/mL of myelin basic protein autoantibodies in EVs from peripheral B cells, with 95.2% sensitivity and 88.2% specificity, which allows us to differentiate MS patients from healthy controls. EV-derived myelin antibodies were also detected in the oligodendrocytes of MS patients. Myelin antibody-loaded EVs from B cells induced myelin markers decrease of oligodendrocytes in vitro.

Discussion

Peripheral reactive immune cells could contribute remotely to MS pathogenesis by delivering myelin antibodies to oligodendrocytes. EV-derived myelin antibodies could play a role as diagnostic biomarker in MS.

Biochemical biomarkers for multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is the most frequent demyelinating disease of the central nervous system. Although there is currently no definite cure for MS, new therapies have recently been developed based on a continuous search for new biomarkers.

DEVELOPMENT

MS diagnosis relies on the integration of clinical, imaging and laboratory findings as there is still no singlepathognomonicclinical feature or diagnostic laboratory biomarker. The most commonly laboratory test used is the presence of immunoglobulin G oligoclonal bands (OCB) in cerebrospinal fluid of MS patients. This test is now included in the 2017 McDonald criteria as a biomarker of dissemination in time. Nevertheless, there are other biomarkers currently in use such as kappa free light chain, which has shown higher sensitivity and specificity for MS diagnosis than OCB. In addition, other potential laboratory tests involved in neuronal damage, demyelination and/or inflammation could be used for detecting MS.

CONCLUSIONS

CSF and serum biomarkers have been reviewed for their use in MS diagnosis and prognosis to stablish an accurate and prompt MS diagnosis, crucial to implement an adequate treatment and to optimize clinical outcomes over time.

The intrinsically disordered protein glue of the myelin major dense line: Linking AlphaFold2 predictions to experimental data

Numerous human proteins are classified as intrinsically disordered proteins (IDPs). Due to their physicochemical properties, high-resolution structural information about IDPs is generally lacking. On the other hand, IDPs are known to adopt local ordered structures upon interactions with e.g. other proteins or lipid membrane surfaces. While recent developments in protein structure prediction have been revolutionary, their impact on IDP research at high resolution remains limited. We took a specific example of two myelin-specific IDPs, the myelin basic protein (MBP) and the cytoplasmic domain of myelin protein zero (P0ct). Both of these IDPs are crucial for normal nervous system development and function, and while they are disordered in solution, upon membrane binding, they partially fold into helices, being embedded into the lipid membrane. We carried out AlphaFold2 predictions of both proteins and analysed the models in light of experimental data related to protein structure and molecular interactions. We observe that the predicted models have helical segments that closely correspond to the membrane-binding sites on both proteins. We furthermore analyse the fits of the models to synchrotron-based X-ray scattering and circular dichroism data from the same IDPs. The models are likely to represent the membrane-bound state of both MBP and P0ct, rather than the conformation in solution. Artificial intelligence-based models of IDPs appear to provide information on the ligand-bound state of these proteins, instead of the conformers dominating free in solution. We further discuss the implications of the predictions for mammalian nervous system myelination and their relevance to understanding disease aspects of these IDPs.

RNA-binding proteins in autoimmunity: From genetics to molecular biology

Autoimmune diseases (ADs) are chronic pathologies generated by the loss of immune tolerance to the body's own cells and tissues. There is growing recognition that RNA-binding proteins (RBPs) critically govern immunity in healthy and pathological conditions by modulating gene expression post-transcriptionally at all levels: nuclear mRNA splicing and modification, export to the cytoplasm, as well as cytoplasmic mRNA transport, storage, editing, stability, and translation. Despite enormous efforts to identify new therapies for ADs, definitive solutions are not yet available in many instances. Recognizing that many ADs have a strong genetic component, we have explored connections between the molecular biology and the genetics of RBPs in ADs. Here, we review the genetics and molecular biology of RBPs in four major ADs, multiple sclerosis (MS), type 1 diabetes mellitus (T1D), systemic lupus erythematosus (SLE), and rheumatoid arthritis (RA). We anticipate that gaining insights into the genetics and biology of ADs can facilitate the discovery of new therapies. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Cellular and Molecular Evidence of Multiple Sclerosis Diagnosis and Treatment Challenges

Multiple sclerosis (MS) is a chronic autoimmune disease that impacts the central nervous system and can result in disability. Although the prevalence of MS has increased in India, diagnosis and treatment continue to be difficult due to several factors. The present study examines the difficulties in detecting and treating multiple sclerosis in India. A lack of MS knowledge among healthcare professionals and the general public, which delays diagnosis and treatment, is one of the significant issues. Inadequate numbers of neurologists and professionals with knowledge of MS management also exacerbate the situation. In addition, MS medications are expensive and not covered by insurance, making them inaccessible to most patients. Due to the absence of established treatment protocols and standards for MS care, India's treatment techniques vary. In addition, India's population diversity poses unique challenges regarding genetic variations, cellular and molecular abnormalities, and the potential for differing treatment responses. MS is more difficult to accurately diagnose and monitor due to a lack of specialized medical supplies and diagnostic instruments. Improved awareness and education among healthcare professionals and the general public, as well as the development of standardized treatment regimens and increased investment in MS research and infrastructure, are required to address these issues. By addressing these issues, it is anticipated that MS diagnosis and treatment in India will improve, leading to better outcomes for those affected by this chronic condition.

Fluchloralin induces developmental toxicity in heart, liver, and nervous system during early zebrafish embryogenesis

The zebrafish is a prominent vertebrate model popularly used for toxicity testing because of its rapid development and transparent embryos. Fluchloralin, a dinitroaniline herbicide used to control weeds, inhibits microtubule formation and cell division. The structurally homologous substances ethalfluralin and pendimethalin, which belong to the dinitroaniline family, were found to be genotoxic and to exert developmental toxicity via mitochondrial dysfunction in a zebrafish model. To date, developmental toxicity of fluchloralin in zebrafish has not been reported. In the present study, we identified morphological changes in developing zebrafish, including decreased survival rate and body length, and increased yolk sac edema. In dose-dependent response to fluchloralin exposure, inhibition of neurogenesis in the spinal cord and motor neuron defects were observed in transgenic zebrafish models (olig2:dsRed). Zebrafish exposed to fluchloralin also displayed organ dysfunction in the heart, liver, and pancreas in cmlc2:dsRed and lfabp:dsRed;elastase:GFP transgenic models. Fluchloralin increased cell death in the brain by promoting apoptosis, visualized via acridine orange staining, and by activating apoptosis signaling proteins, including cytochrome c1, zBax, and Bcl-XL. This study provides novel evidence supporting the necessity of controlling pollutants in aquatic environments.

Immune Regulatory Functions of Macrophages and Microglia in Central Nervous System Diseases

Macrophages can be characterized as a very multifunctional cell type with a spectrum of phenotypes and functions being observed spatially and temporally in various disease states. Ample studies have now demonstrated a possible causal link between macrophage activation and the development of autoimmune disorders. How these cells may be contributing to the adaptive immune response and potentially perpetuating the progression of neurodegenerative diseases and neural injuries is not fully understood. Within this review, we hope to illustrate the role that macrophages and microglia play as initiators of adaptive immune response in various CNS diseases by offering evidence of: (1) the types of immune responses and the processes of antigen presentation in each disease, (2) receptors involved in macrophage/microglial phagocytosis of disease-related cell debris or molecules, and, finally, (3) the implications of macrophages/microglia on the pathogenesis of the diseases.

A fatal alliance: Glial connexins, myelin pathology and mental disorders

Mature oligodendrocytes are myelin forming glial cells which are responsible for myelination of neuronal axons in the white matter of the central nervous system. Myelin pathology is a major feature of severe neurological disorders. Oligodendrocyte-specific gene mutations and/or white matter alterations have also been addressed in a variety of mental disorders. Breakdown of myelin integrity and demyelination is associated with severe symptoms, including impairments in motor coordination, breathing, dysarthria, perception (vision and hearing), and cognition. Furthermore, there is evidence indicating that myelin sheath defects and white matter pathology contributes to the affective and cognitive symptoms of patients with mental disorders. Oligodendrocytes express the connexins GJC2; mCx47 [human (GJC2) and mouse (mCx47) connexin gene nomenclature according to Söhl and Willecke (2003)], GJB1; mCx32, and GJD1; mCx29 in both white and gray matter. Preclinical findings indicate that alterations in connexin expression in oligodendrocytes and astrocytes can induce myelin defects. GJC2; mCx47 is expressed at early embryonic stages in oligodendrocyte precursors cells which precedes central nervous system myelination. In adult humans and animals GJC2, respectively mCx47 expression is essential for oligodendrocyte function and ensures adequate myelination as well as myelin maintenance in the central nervous system. In the past decade, evidence has accumulated suggesting that mental disorders can be accompanied by changes in connexin expression, myelin sheath defects and corresponding white matter alterations. This dual pathology could compromise inter-neuronal information transfer, processing and communication and eventually contribute to behavioral, sensory-motor, affective and cognitive symptoms in patients with mental disorders. The induction of myelin repair and remyelination in the central nervous system of patients with mental disorders could help to restore normal neuronal information propagation and ameliorate behavioral and cognitive symptoms in individuals with mental disorders.

Association between human herpesviruses and multiple sclerosis: A systematic review and meta-analysis

AIM

The aim of this study was to investigate the prevalence and potential association between infection with different herpes viruses and multiple sclerosis (MS).

METHODS

A systematic literature search was performed by finding relevant cross-sectional and case-control studies from a large online database. Heterogeneity, Odds ratio (OR), and corresponding 95% Confidence interval (CI) were applied to all studies by meta-analysis and forest plots. The analysis was performed using Stata Software v.14.

RESULTS

One hundred and thirty-four articles (289 datasets) were included in the meta-analysis, 128 (245 datasets) of which were case/control and the rest were cross-sectional. The pooled prevalence of all human herpes viruses among MS patients was 50% (95% CI: 45-55%; I2 = 96.91%). In subgroup analysis, the pooled prevalence of Herpes simplex virus (HSV), Varicella-zoster virus (VZV), Epstein-Barr virus (EBV), Cytomegalovirus (CMV), Human herpes virus 6 (HHV-6), Human herpes virus 7 (HHV-7), and Human herpes virus 8 (HHV-8) was 32%, 52%, 74%, 41%, 39% 28%, and 28%, respectively. An association was found between infection with human herpes viruses and MS [summary OR 2.07 (95% CI (1.80-2.37); I2 = 80%)].

CONCLUSION

The results of the present study showed that EBV, VZV, and HHV-6 infection are associated with multiple sclerosis and can be considered as potential risk factors for MS. Although the exact molecular mechanism of the role of herpes viruses in the development of MS is still unknown, it seems that molecular mimicry, the release of autoreactive antibodies, and inflammation in the CNS following viral infection can be important factors in the induction of MS.

Semaglutide, a novel glucagon-like peptide-1 agonist, amends experimental autoimmune encephalomyelitis-induced multiple sclerosis in mice: Involvement of the PI3K/Akt/GSK-3β pathway

Multiple sclerosis (MS) is a disabling neurodegenerative disease that causes demyelination and axonal degeneration of the central nervous system. Current treatments are partially effective in managing MS relapses and have a negligible impact on treating MS cognitive deficits and cannot enhance neuronal remyelination, imposing a need for a new MS remedy. Semaglutide, a novel glucagon-like peptide-1 agonist, has recently displayed a neuroprotective effect on several neurodegenerative diseases, suggesting that it may have a protective effect in MS. Therefore, this study was conducted to investigate the influence of semaglutide on experimental autoimmune encephalomyelitis (EAE)-induced MS in mice. Here, EAE was induced in mice using spinal cord homogenate, which eventually altered the mice's cognitive and motor functions, similar to what is observed in MS. Interestingly, intraperitoneally administered semaglutide (25 nmol/kg/day) amended EAE-induced cognitive and motor deficits observed in novel object recognition, open field, rotarod, and grip strength tests. Moreover, histological examination revealed that semaglutide treatment attenuated hippocampal damage and corpus callosum demyelination caused by EAE. Additionally, biochemical testing revealed that semaglutide activates the PI3K/Akt axis, which eventually hampers GSK-3β activity. GSK-3β activity inhibition attenuates demyelination and triggers remyelination through CREB/BDNF; furthermore, it boosts Nrf2 and SOD levels, protecting the mice from EAE-induced oxidative stress. Additionally, GSK-3β inhibition minimizes neuroinflammation, as reflected by decreased NF-kβ and TNF-α levels. In conclusion, semaglutide has a neuroprotective effect in EAE-induced MS in mice, which is mediated by activating the ramified PI3K/Akt/GSK-3β pathway.

MHC Class II Presentation in Autoimmunity

Antigen presentation by major histocompatibility complex class II (MHC-II) molecules is crucial for eliciting an efficient immune response by CD4+ T cells and maintaining self-antigen tolerance. Some MHC-II alleles are known to be positively or negatively associated with the risk of the development of different autoimmune diseases (ADs), including those characterized by the emergence of autoreactive T cells. Apparently, the MHC-II presentation of self-antigens contributes to the autoimmune T cell response, initiated through a breakdown of central tolerance to self-antigens in the thymus. The appearance of autoreactive T cell might be the result of (i) the unusual interaction between T cell receptors (TCRs) and self-antigens presented on MHC-II; (ii) the posttranslational modifications (PTMs) of self-antigens; (iii) direct loading of the self-antigen to classical MHC-II without additional nonclassical MHC assistance; (iv) the proinflammatory environment effect on MHC-II expression and antigen presentation; and (v) molecular mimicry between foreign and self-antigens. The peculiarities of the processes involved in the MHC-II-mediated presentation may have crucial importance in the elucidation of the mechanisms of triggering and developing ADs as well as for clarification on the protective effect of MHC-II alleles that are negatively associated with ADs.

Multiple strategies enhance the efficacy of MSCs transplantation for spinal cord injury

Spinal cord injury (SCI) is a serious complication of the central nervous system (CNS) after spine injury, often resulting in severe sensory, motor, and autonomic dysfunction below the level of injury. To date, there is no effective treatment strategy for SCI. Recently, stem cell therapy has brought hope to patients with neurological diseases. Mesenchymal stem cells (MSCs) are considered to be the most promising source of cellular therapy after SCI due to their immunomodulatory, neuroprotective and angiogenic potential. Considering the limited therapeutic effect of MSCs due to the complex pathophysiological environment following SCI, this paper not only reviews the specific mechanism of MSCs to facilitate SCI repair, but also further discusses the research status of these pluripotent stem cells combined with other therapeutic approaches to promote anatomical and functional recovery post-SCI.

In Silico Structural Analysis Predicting the Pathogenicity of PLP1 Mutations in Multiple Sclerosis

The X chromosome gene PLP1 encodes myelin proteolipid protein (PLP), the most prevalent protein in the myelin sheath surrounding the central nervous system. X-linked dysmyelinating disorders such as Pelizaeus-Merzbacher disease (PMD) or spastic paraplegia type 2 (SPG2) are typically caused by point mutations in PLP1. Nevertheless, numerous case reports have shown individuals with PLP1 missense point mutations which also presented clinical symptoms and indications that were consistent with the diagnostic criteria of multiple sclerosis (MS), a disabling disease of the brain and spinal cord with no current cure. Computational structural biology methods were used to assess the impact of these mutations on the stability and flexibility of PLP structure in order to determine the role of PLP1 mutations in MS pathogenicity. The analysis showed that most of the variants can alter the functionality of the protein structure such as R137W variants which results in loss of helix and H140Y which alters the ordered protein interface. In silico genomic methods were also performed to predict the significance of these mutations associated with impairments in protein functionality and could suggest a better definition for therapeutic strategies and clinical application in MS patients.

Huperzine-A Improved Animal Behavior in Cuprizone-Induced Mouse Model by Alleviating Demyelination and Neuroinflammation

Huperzine A (HupA) is a natural acetylcholinesterase inhibitor (AChEI) with the advantages of high efficiency, selectivity as well as reversibility and can exhibit significant therapeutic effects against certain neurodegenerative diseases. It is also beneficial in reducing the neurological impairment and neuroinflammation of experimental autoimmune encephalomyelitis (EAE), a classic model for multiple sclerosis (MS). However, whether HupA can directly regulate oligodendrocyte differentiation and maturation and promote remyelination has not been investigated previously. In this study, we have analyzed the potential protective effects of HupA on the demylination model of MS induced by cuprizone (CPZ). It was found that HupA significantly attenuated anxiety-like behavior, as well as augmented motor and cognitive functions in CPZ mice. It also decreased demyelination and axonal injury in CPZ mice. Moreover, in CPZ mice, HupA increased mRNA levels of the various anti-inflammatory cytokines (Arg1, CD206) while reducing the levels of different pro-inflammatory cytokines (iNOS, IL-1β, IL-18, CD16, and TNF-α). Mecamylamine, a nicotinic acetylcholinergic receptor antagonist, could effectively reverse the effects of HupA. Therefore, we concluded that HupA primarily exerts its therapeutic effects on multiple sclerosis through alleviating demyelination and neuroinflammation.

The Mammalian Cysteine Protease Legumain in Health and Disease

The cysteine protease legumain (also known as asparaginyl endopeptidase or δ-secretase) is the only known mammalian asparaginyl endopeptidase and is primarily localized to the endolysosomal system, although it is also found extracellularly as a secreted protein. Legumain is involved in the regulation of diverse biological processes and tissue homeostasis, and in the pathogenesis of various malignant and nonmalignant diseases. In addition to its proteolytic activity that leads to the degradation or activation of different substrates, legumain has also been shown to have a nonproteolytic ligase function. This review summarizes the current knowledge about legumain functions in health and disease, including kidney homeostasis, hematopoietic homeostasis, bone remodeling, cardiovascular and cerebrovascular diseases, fibrosis, aging and senescence, neurodegenerative diseases and cancer. In addition, this review addresses the effects of some marketed drugs on legumain. Expanding our knowledge on legumain will delineate the importance of this enzyme in regulating physiological processes and disease conditions.

Deciphering the Genetic Crosstalk between Microglia and Oligodendrocyte Precursor Cells during Demyelination and Remyelination Using Transcriptomic Data

Demyelinating disorders show impaired remyelination due to failure in the differentiation of oligodendrocyte progenitor cells (OPCs) into mature myelin-forming oligodendrocytes, a process driven by microglia-OPC crosstalk. Through conducting a transcriptomic analysis of microarray studies on the demyelination-remyelination cuprizone model and using human samples of multiple sclerosis (MS), we identified molecules involved in this crosstalk. Differentially expressed genes (DEGs) of specific regions/cell types were detected in GEO transcriptomic raw data after cuprizone treatment and in MS samples, followed by functional analysis with GO terms and WikiPathways. Additionally, microglia-OPC crosstalk between microglia ligands, OPC receptors and target genes was examined with the NicheNet model. We identified 108 and 166 DEGs in the demyelinated corpus callosum (CC) at 2 and 4 weeks of cuprizone treatment; 427 and 355 DEGs in the remyelinated (4 weeks of cuprizone treatment + 14 days of normal diet) compared to 2- and 4-week demyelinated CC; 252 DEGs in MS samples and 2730 and 12 DEGs in OPC and microglia of 4-week demyelinated CC. At this time point, we found 95 common DEGs in the CC and OPCs, and one common DEG in microglia and OPCs, mostly associated with myelin and lipid metabolism. Crosstalk analysis identified 47 microglia ligands, 43 OPC receptors and 115 OPC target genes, all differentially expressed in cuprizone-treated samples and associated with myelination. Our differential expression pipeline identified demyelination/remyelination transcriptomic biomarkers in studies using diverse platforms and cell types/tissues. Cellular crosstalk analysis yielded novel markers of microglia ligands, OPC receptors and target genes.

Intrinsic Disorder as a Natural Preservative: High Levels of Intrinsic Disorder in Proteins Found in the 2600-Year-Old Human Brain

Proteomic analysis revealed the preservation of many proteins in the Heslington brain (which is at least 2600-year-old brain tissue uncovered within the skull excavated in 2008 from a pit in Heslington, Yorkshire, England). Five of these proteins-"main proteins": heavy, medium, and light neurofilament proteins (NFH, NFM, and NFL), glial fibrillary acidic protein (GFAP), and myelin basic (MBP) protein-are engaged in the formation of non-amyloid protein aggregates, such as intermediate filaments and myelin sheath. We used a wide spectrum of bioinformatics tools to evaluate the prevalence of functional disorder in several related sets of proteins, such as the main proteins and their 44 interactors, all other proteins identified in the Heslington brain, as well as the entire human proteome (20,317 manually curated proteins), and 10,611 brain proteins. These analyses revealed that all five main proteins, half of their interactors and almost one third of the Heslington brain proteins are expected to be mostly disordered. Furthermore, most of the remaining Heslington brain proteins are expected to contain sizable levels of disorder. This is contrary to the expected substantial (if not complete) elimination of the disordered proteins from the Heslington brain. Therefore, it seems that the intrinsic disorder of NFH, NFM, NFL, GFAP, and MBP, their interactors, and many other proteins might play a crucial role in preserving the Heslington brain by forming tightly folded brain protein aggregates, in which different parts are glued together via the disorder-to-order transitions.

Molecular Mimicry Analyses Unveiled the Human Herpes Simplex and Poxvirus Epitopes as Possible Candidates to Incite Autoimmunity

Clinical epidemiological studies have reported that viral infections cause autoimmune pathology in humans. Host-pathogen protein sequences and structure-based molecular mimicry cause autoreactive T cells to cross-activate. The aim of the current study was to implement immunoinformatics approaches to infer sequence- and structure-based molecular mimicry between viral and human proteomic datasets. The protein sequences of all the so far known human-infecting viruses were obtained from the VIPR database, and complete human proteome data were retrieved from the NCBI repository. Based on a predefined, stringent threshold of comparative sequence analyses, 24 viral proteins were identified with significant sequence similarity to human proteins. PathDIP identified the enrichment of these homologous proteins in nine metabolic pathways with a p-value < 0.0001. Several viral and human mimic epitopes from these homologous proteins were predicted as strong binders of human HLA alleles, with IC50 < 50 nM. Downstream molecular docking analyses identified that lead virus-human homologous epitopes feasibly interact with HLA and TLR4 types of immune receptors. The vast majority of these top-hit homolog epitopic peptides belong to the herpes simplex and poxvirus families. These lead epitope biological sequences and 3D structural-based molecular mimicry may be promising for interpreting herpes simplex virus and poxvirus infection-mediated autoimmune disorders in humans.

Functional Diversity of Neuronal Cell Adhesion and Recognition Molecule L1CAM through Proteolytic Cleavage

The neuronal cell adhesion and recognition molecule L1 does not only 'keep cells together' by way of homophilic and heterophilic interactions, but can also promote cell motility when cleaved into fragments by several proteases. It has largely been thought that such fragments are signs of degradation. Now, it is clear that proteolysis contributes to the pronounced functional diversity of L1, which we have reviewed in this work. L1 fragments generated at the plasma membrane are released into the extracellular space, whereas other membrane-bound fragments are internalised and enter the nucleus, thus conveying extracellular signals to the cell interior. Post-translational modifications on L1 determine the sequence of cleavage by proteases and the subcellular localisation of the generated fragments. Inside the neuronal cells, L1 fragments interact with various binding partners to facilitate morphogenic events, as well as regenerative processes. The stimulation of L1 proteolysis via injection of L1 peptides or proteases active on L1 or L1 mimetics is a promising tool for therapy of injured nervous systems. The collective findings gathered over the years not only shed light on the great functional diversity of L1 and its fragments, but also provide novel mechanistic insights into the adhesion molecule proteolysis that is active in the developing and diseased nervous system.

Autoreactive lymphocytes in multiple sclerosis: Pathogenesis and treatment target

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by destruction of the myelin sheath structure. The loss of myelin leads to damage of a neuron’s axon and cell body, which is identified as brain lesions on magnetic resonance image (MRI). The pathogenesis of MS remains largely unknown. However, immune mechanisms, especially those linked to the aberrant lymphocyte activity, are mainly responsible for neuronal damage. Th1 and Th17 populations of lymphocytes were primarily associated with MS pathogenesis. These lymphocytes are essential for differentiation of encephalitogenic CD8⁺ T cell and Th17 lymphocyte crossing the blood brain barrier and targeting myelin sheath in the CNS. B-lymphocytes could also contribute to MS pathogenesis by producing anti-myelin basic protein antibodies. In later studies, aberrant function of Treg and Th9 cells was identified as contributing to MS. This review summarizes the aberrant function and count of lymphocyte, and the contributions of these cell to the mechanisms of MS. Additionally, we have outlined the novel MS therapeutics aimed to amend the aberrant function or counts of these lymphocytes.

Antioxidant effect of grape seed extract corrects experimental autoimmune encephalomyelitis behavioral dysfunctions, demyelination, and glial activation

Background and purpose

Multiple sclerosis (MS), a multifactorial autoimmune disease of the central nervous system (CNS), is characterized by demyelination and chronic inflammation, as well as axonal and neuronal loss. There is no cure for MS, and despite a significant improvement in the therapeutic management of patients during the last 20 years, some symptoms are still resistant to treatment, and the evolution of the disease to progressive form seems still ineluctable. The etiology of MS is complex and still not fully understood. However, inflammation is a major driver of physiopathology and oxidative stress contributes to CNS lesions and promotes existing inflammatory response. Plant polyphenols are endowed with many therapeutic benefits through alleviating oxidative stress and inflammation, thus providing neuroprotection in MS. We presently evaluated the curative effect of grape seed extract (GSE) in an experimental autoimmune encephalomyelitis (EAE) mouse model of MS.

Experimental approach

Six-week-old C57Bl/6J females were subjected to the EAE paradigm (using myelin oligodendrocyte glycoprotein peptide fragment (35-55), complete Freund’s adjuvant, and pertussis toxin) and then chronically treated with GSE from day 10 to day 30 post-induction. Clinical score and body weight were monitored daily, while evaluation of sensitive, motor, cognitive, and anxiety-related behaviors was performed weekly. Then, the GSE effect was evaluated on whole brain and spinal cord samples through the evaluation of oxidative stress damage, antioxidant capacities, myelin alteration, astroglial and microglial proliferation, and sirtuin expression.

Key results

Grape seed extract curative chronic treatment corrected the clinical course of EAE, as well as the mechanical hypersensitivity, and avoided the development of EAE mouse thermal cold allodynia. The neuropathological evaluation showed that GSE reduced oxidative stress in the brain and spinal cord by decreasing the lipid and protein oxidation through correction of the three main antioxidant enzyme activities, namely, superoxide dismutase, catalase, and glutathione peroxidase, as well as restoring normal myelin protein expression and correcting microglial and astroglial protein overexpression and sirtuin downregulation.

Conclusion and implications

These data strongly support GSE as an effective therapeutic approach in MS treatment.

The mosaic of autoimmunity - Finally discussing in person. The 13th international congress on autoimmunity 2022 (AUTO13) Athens

While autoimmunity is a branch of medicine linked to every single organ system via direct and indirect pathways, meeting in person to discuss autoimmunity during the 13^th international congress on autoimmunity (AUTO13) with participants from all over the world had a very good reason. The mechanisms involved in autoimmune diseases are of extreme importance and in fact critical in understanding the course of diseases as well as selecting proper therapies. COVID-19 has served as a great example of how autoimmunity is deeply involved in the disease and directly correlated to severity, morbidity, and mortality. For instance, initially the term cytokine storm dominated, then COVID-19 was addressed as the new member of the hyperferritinemic syndrome, and also the use of immunosuppressants in patients with COVID-19 throughout the pandemic, all shed light on the fundamental role of autoimmunity. Unsurprisingly, SARS-CoV-2 was called the “autoimmune virus” during AUTO13. Subsequently, the correlation between autoimmunity and COVID-19 vaccines and post-COVID, all were discussed from different autoimmune aspects during the congress. In addition, updates on the mechanisms of diseases, autoantibodies, novel diagnostics and therapies in regard to autoimmune diseases such as antiphospholipid syndrome, systemic lupus erythematosus, systemic sclerosis and others, were discussed in dedicated sessions. Due to the magnificence of the topics discussed, we aimed to bring in our article hereby, the pearls of AUTO13 in terms of updates, new aspects of autoimmunity, and interesting findings. While more than 500 abstract were presented, concluding all the topics was not in reach, hence major findings were summarized.

A single-nucleus transcriptomic atlas of the dog hippocampus reveals the potential relationship between specific cell types and domestication

The process of domestication has led to dramatic differences in behavioral traits between domestic dogs and gray wolves. Whole-genome research found that a class of putative positively selected genes were related to various aspects of learning and memory, such as long-term potentiation and long-term depression. In this study, we constructed a single-nucleus transcriptomic atlas of the dog hippocampus to illustrate its cell types, cell lineage and molecular features. Using the transcriptomes of 105 057 nuclei from the hippocampus of a Beagle dog, we identified 26 cell clusters and a putative trajectory of oligodendrocyte development. Comparative analysis revealed a significant convergence between dog differentially expressed genes (DEGs) and putative positively selected genes (PSGs). Forty putative PSGs were DEGs in glutamatergic neurons, especially in Cluster 14, which is related to the regulation of nervous system development. In summary, this study provides a blueprint to understand the cellular mechanism of dog domestication.

Heritability Estimation of Multiple Sclerosis Related Plasma Protein Levels in Sardinian Families with Immunochip Genotyping Data

This work aimed at estimating narrow-sense heritability, defined as the proportion of the phenotypic variance explained by the sum of additive genetic effects, via Haseman–Elston regression for a subset of 56 plasma protein levels related to Multiple Sclerosis (MS). These were measured in 212 related individuals (with 69 MS cases and 143 healthy controls) obtained from 20 Sardinian families with MS history. Using pedigree information, we found seven statistically significant heritable plasma protein levels (after multiple testing correction), i.e., Gc (h2 = 0.77; 95%CI: 0.36, 1.00), Plat (h2 = 0.70; 95%CI: 0.27, 0.95), Anxa1 (h2 = 0.68; 95%CI: 0.27, 1.00), Sod1 (h2 = 0.58; 95%CI: 0.18, 0.96), Irf8 (h2 = 0.56; 95%CI: 0.19, 0.99), Ptger4 (h2 = 0.45; 95%CI: 0.10, 0.96), and Fadd (h2 = 0.41; 95%CI: 0.06, 0.84). A subsequent analysis was performed on these statistically significant heritable plasma protein levels employing Immunochip genotyping data obtained in 155 healthy controls (92 related and 63 unrelated); we found a meaningful proportion of heritable plasma protein levels’ variability explained by a small set of SNPs. Overall, the results obtained, for these seven MS-related proteins, emphasized a high additive genetic variance component explaining plasma levels’ variability.

Catalytic Antibodies in Bipolar Disorder: Serum IgGs Hydrolyze Myelin Basic Protein

The pathogenesis of bipolar affective disorder is associated with immunological imbalances, a general pro-inflammatory status, neuroinflammation, and impaired white matter integrity. Myelin basic protein (MBP) is one of the major proteins in the myelin sheath of brain oligodendrocytes. For the first time, we have shown that IgGs isolated from sera of bipolar patients can effectively hydrolyze human myelin basic protein (MBP), unlike other test proteins. Several stringent criteria were applied to assign the studied activity to serum IgG. The level of MBP-hydrolyzing activity of IgG from patients with bipolar disorder was statistically significantly 1.6-folds higher than that of healthy individuals. This article presents a detailed characterization of the catalytic properties of MBP-hydrolyzing antibodies in bipolar disorder, including the substrate specificity, inhibitory analysis, pH dependence of hydrolysis, and kinetic parameters of IgG-dependent MBP hydrolysis, providing the heterogeneity of polyclonal MBP-hydrolyzing IgGs and their difference from canonical proteases. The ability of serum IgG to hydrolyze MBP in bipolar disorder may become an additional link between the processes of myelin damage and inflammation.

Investigation of differentially expressed genes and dysregulated pathways involved in multiple sclerosis

Multiple Sclerosis (MS) is a neurodegenerative autoimmune and organ-specific demyelinating disorder, known to affect the central nervous system (CNS). While genetic studies have revealed several critical genes and diagnostic biomarkers associated with MS, the etiology of the disease remains poorly understood. This study is aimed at screening and identifying the key genes and canonical pathways associated with MS. Gene expression profiling of the microarray dataset GSE38010 was used to analyze two control brain samples (control 1; GSM931812, control 2; GSM931813), active inflammation stage samples (CAP1; GSM931815, CAP2; GSM931816) and late subsided stage samples (CP1; GSM931817, CP2; GSM931818) collected from patients ranging between 23 and 54years and both genders. This analysis yielded a list of 58,866 DEGs (29,433 for active-inflammation stage and 29,433 for late-subsided Stage). The interactions between the DEGs were then studied using STRING, Cytoscape software, and MCODE was employed to find the genes that form clusters. Functional enrichment and integrative analysis were performed using ClueGO/CluePedia and MetaCore™. Our data revealed dysregulated key canonical pathways in MS patients. In addition, we identified three hub genes (SCN2A, HTR2A, and HCN1) that may serve as potential biomarkers for the prognosis of MS. Furthermore, the expression patterns of HPCA and PLCB1 provide insights into the progressive stages of MS, indicating that these genes could be used in predicting MS progression. We were able to map potential biomarkers that could be used for the prognosis and diagnosis of MS.