Environmental risk factors for multiple sclerosis: a review with a focus on molecular mechanisms

The molecular subtypes of autoimmune diseases

Autoimmune diseases (ADs) are characterized by their complexity and a wide range of clinical differences. Despite patients presenting with similar symptoms and disease patterns, their reactions to treatments may vary. The current approach of personalized medicine, which relies on molecular data, is seen as an effective method to address the variability in these diseases. This review examined the pathologic classification of ADs, such as multiple sclerosis and lupus nephritis, over time. Acknowledging the limitations inherent in pathologic classification, the focus shifted to molecular classification to achieve a deeper insight into disease heterogeneity. The study outlined the established methods and findings from the molecular classification of ADs, categorizing systemic lupus erythematosus (SLE) into four subtypes, inflammatory bowel disease (IBD) into two, rheumatoid arthritis (RA) into three, and multiple sclerosis (MS) into a single subtype. It was observed that the high inflammation subtype of IBD, the RA inflammation subtype, and the MS "inflammation & EGF" subtype share similarities. These subtypes all display a consistent pattern of inflammation that is primarily driven by the activation of the JAK-STAT pathway, with the effective drugs being those that target this signaling pathway. Additionally, by identifying markers that are uniquely associated with the various subtypes within the same disease, the study was able to describe the differences between subtypes in detail. The findings are expected to contribute to the development of personalized treatment plans for patients and establish a strong basis for tailored approaches to treating autoimmune diseases.

Disentangling Multiple Sclerosis heterogeneity in the French territory among genetic and environmental factors via Bayesian heritability analysis

BACKGROUND

This study aimed to investigate the factors contributing to the variability of Multiple Sclerosis (MS) among individuals born and residing in France. Geographical variation in MS prevalence was observed in France, but the role of genetic and environmental factors in explaining this heterogeneity has not been yet elucidated.

METHODS

We employed a heritability analysis on a cohort of 403 trios with an MS-affected proband in the French population. This sample was retrieved from REFGENSEP register of MS cases collected in 23 French hospital centers from 1992 to 2017. Our objective was to quantify the proportion of MS liability variability explained by genetic variability, sex, shared environment effects, region of birth and year of birth. We further considered gene x environment (GxE) interaction effects between genetic variability and region of birth. We have implemented a Bayesian liability threshold model to obtain posterior distributions for the parameters of interest adjusting for ascertainment bias.

RESULTS

Our analysis revealed that GxE interaction effects between genetic variability and region of birth represent the primary significant explanatory factor for MS liability variability in French individuals (29 % [95 %CI: 5 %; 53 %]), suggesting that additive genetic effects are modified by environmental factors associated to the region of birth. The individual contributions of genetic variability and region of birth explained, respectively, ≈15 % and ≈16 % of MS variability, highlighting a significantly higher MS liability in individuals born in the Northern regions compared to the Southern region. Overall, the joint contribution of genetic variability, region of birth, and their interaction was then estimated to explain 65 % [95 %CI: 35 %; 92 %] of MS liability variability. The remaining proportion of MS variability is attributed to environmental exposures associated with the year of birth, shared within the same household, and specific to individuals.

CONCLUSION

Overall, our analysis highlighted the interaction between genetic variability and environmental exposures linked to the region of birth as the main factor explaining MS variability within individuals born and residing in France. Among the environmental exposures prevalent in the Northern regions, and potentially interacting with genetic variability, lower vitamin D levels due to reduced sun exposure, higher obesity prevalence and higher pollution levels represent the main risk factors in influencing MS risk. These findings emphasize the importance of accounting for environmental factors linked to geographical location in the investigation of MS risk factors, as well as to further explore the influence of GxE interactions in modifying genetic risk.

Discovery of Novel Azaindoles as Potent and Selective PI3Kδ Inhibitors for Treatment of Multiple Sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disorder of the central nervous system and the unmet need for MS treatment demands new therapeutic development. Particularly, PI3Kδ is a high-value target for autoimmune disease, while the investigation of PI3Kδ inhibitors for MS therapy is relatively scarce. Herein, we report a novel class of azaindoles as PI3Kδ inhibitors for MS treatment. Compound 31, designed via nitrogen bioisosterism, displayed excellent PI3Kδ inhibitory activity and selectivity. In vitro assay showed that 31 exhibited superior activity on T lymphocytes to inhibit the proliferation of CD4+, CD8+, and CD3+ T cells. In the experimental autoimmune encephalomyelitis (EAE) model, 31 showed a comparable therapeutical efficacy with Dexamethasone to significantly ameliorate EAE symptoms. Mechanistic studies showed that compound 31 could significantly inhibit the PI3K/AKT/mTOR signaling pathway and inhibited T-cell proliferation and differentiation. Overall, this work provides a new structural PI3Kδ inhibitor and a new vision for MS therapy.

MicroRNA biomarkers as next-generation diagnostic tools for neurodegenerative diseases: a comprehensive review

Neurodegenerative diseases (NDs) are characterized by abnormalities within neurons of the brain or spinal cord that gradually lose function, eventually leading to cell death. Upon examination of affected tissue, pathological changes reveal a loss of synapses, misfolded proteins, and activation of immune cells-all indicative of disease progression-before severe clinical symptoms become apparent. Early detection of NDs is crucial for potentially administering targeted medications that may delay disease advancement. Given their complex pathophysiological features and diverse clinical symptoms, there is a pressing need for sensitive and effective diagnostic methods for NDs. Biomarkers such as microRNAs (miRNAs) have been identified as potential tools for detecting these diseases. We explore the pivotal role of miRNAs in the context of NDs, focusing on Alzheimer's disease, Parkinson's disease, Multiple sclerosis, Huntington's disease, and Amyotrophic Lateral Sclerosis. The review delves into the intricate relationship between aging and NDs, highlighting structural and functional alterations in the aging brain and their implications for disease development. It elucidates how miRNAs and RNA-binding proteins are implicated in the pathogenesis of NDs and underscores the importance of investigating their expression and function in aging. Significantly, miRNAs exert substantial influence on post-translational modifications (PTMs), impacting not just the nervous system but a wide array of tissues and cell types as well. Specific miRNAs have been found to target proteins involved in ubiquitination or de-ubiquitination processes, which play a significant role in regulating protein function and stability. We discuss the link between miRNA, PTM, and NDs. Additionally, the review discusses the significance of miRNAs as biomarkers for early disease detection, offering insights into diagnostic strategies.

Resting heart rate and risk of dementia: a Mendelian randomization study in the international genomics of Alzheimer's Project and UK Biobank

Background

Observational studies have demonstrated that a higher resting heart rate (RHR) is associated with an increased risk of dementia. However, it is not clear whether the association is causal. This study aimed to determine the causal effects of higher genetically predicted RHR on the risk of dementia.

Methods

We performed a two-sample Mendelian randomization analysis to investigate the causal effect of higher genetically predicted RHR on Alzheimer's disease (AD) using summary statistics from genome-wide association studies. The generalized summary Mendelian randomization (GSMR) analysis was used to analyze the corresponding effects of RHR on following different outcomes: 1) diagnosis of AD (International Genomics of Alzheimer's Project), 2) family history (maternal and paternal) of AD from UK Biobank, 3) combined meta-analysis including these three GWAS results. Further analyses were conducted to determine the possibility of reverse causal association by adjusting for RHR modifying medication.

Results

The results of GSMR showed no significant causal effect of higher genetically predicted RHR on the risk of AD (βGSMR = 0.12, P = 0.30). GSMR applied to the maternal family history of AD (βGSMR = -0.18, P = 0.13) and to the paternal family history of AD (βGSMR = -0.14, P = 0.39) showed the same results. Furthermore, the results were robust after adjusting for RHR modifying drugs (βGSMR = -0.03, P = 0.72).

Conclusion

Our study did not find any evidence that supports a causal effect of RHR on dementia. Previous observational associations between RHR and dementia are likely attributed to the correlation between RHR and other cardiovascular diseases.

Herpes viral infection and the multiple sclerosis prodrome: is HHV-6A infection a second hit?

This scientific commentary refers to ‘Human herpesvirus 6A and axonal injury before the clinical onset of multiple sclerosis’ by Grut et al. (https://doi.org/10.1093/brain/awad374).

Occupational risk factors for multiple sclerosis: a systematic review with meta-analysis

Objective

We decided to conduct the first systematic review with meta-analysis to provide the highest level of up-to-date evidence on the occupational risk factors for Multiple Sclerosis.

Methods

A systematic, comprehensive literature search was performed in four electronic academic databases. We included any case-control study that enrolled working-age subjects and compared the proportion of MS cases with controls who were not exposed to an occupational risk factor. The primary outcome was the occurrence of MS. The quality assessment was performed with the Critical Appraisal Checklist for Case Control Studies, developed, and validated by the Joanna Briggs Institute. All the selection process was also carried out by two independent and previously trained researchers.

Results

Overall, the total sample included 19,004 people with MS and 4,164,162 controls. Agricultural workers (OR = 1.44, 95% CI 1.13-1.83), offshore workers (OR = 3.56, 95% CI 2.74-4.61), and hairdressers (OR = 8.25, 95% CI 1.02-66.52) were associated with a higher probability of being diagnosed with MS. In parallel, workers exposed to toxic fumes from oil wells (OR = 16.80, 95% CI 8.33-33.90), low-frequency magnetic fields (OR = 1.71, 95% CI 1.03-2.72), and pesticides (OR = 3.17, 95% CI = 2.53-3.99) also had an increased likelihood of having MS.

Conclusion

Our study has the potential to influence more assertive public policies. Nevertheless, future studies on how the occupational setting may contribute to the incidence of MS are highly recommended.

Systematic review registration

The protocol was registered in the international prospective register of systematic reviews (PROSPERO- CRD42023443257).

Cross-reactivity between Mycobacterium avium subspecies paratuberculosis 4027 peptide and Human IRF5 may contribute to Multiple Sclerosis in Iranian patients

Background

The etiology of Multiple sclerosis (MS) is complicated and can be affected by several environmental factors, such as Mycobacterium avium subspecies paratuberculosis (MAP) infection in genetically predisposed individuals. The link between MAP and MS depends on host genetic and epigenetic aspects and population-based features that require further investigation. We aimed to study the possible role of MAP in triggering MS using molecular and serological methods.

Materials and methods

This case-control study examined 200 blood samples (100 MS patients and 100 HCs) to search for the MAP-specific IS900 gene. In addition, ELISA was conducted to determine the humoral response against MAP_402718-32 and its human IRF5424-434 peptide homolog.

Results

The frequency of MAP detection based on the molecular method in MS patients and HCs was 48 % and 13 %, respectively (p < 0.0001). The presence of antibodies against MAP_402718-32 and IRF5424-434 was 55 % and 65 % in MS patients versus 9 % and 7 % in HCs, respectively (p < 0.0001). A good correlation was observed between MAP_4027 and IRF5 antibodies (r = 0.5782, p < 0.0001), indicating that the same antibodies recognized common peptide epitopes.

Conclusion

Our research revealed a significant association between MAP and MS, highlighting the possible role of MAP as an important infection trigger factor of MS. It is hypothesized that cross-reactivity between MAP4027 and IRF5 may dysregulate immune homeostasis.

Is cancer risk reduced in multiple sclerosis? Results from a tertiary referral center

BACKGROUND

Multiple sclerosis (MS) patients may be protected against cancer because of increased immune surveillance. However, aberrant T/B cell functioning in MS may increase the risk of cancer. We aimed to compare the frequency of cancer among patients with MS with an appropriate control group matched by the variables such as age, gender, tobacco smoking history, body mass index (BMI), and family history of cancer.

METHODS

The MS patients who were registered and followed up at the MS Center in Hacettepe University Hospitals and appropriately matched with controls were included. A self-administered questionnaire with links to the online survey was delivered.

RESULTS

Overall, 1037 responses out of 2074 in MS patients and 506 responses out of 1500 control group were included. Fourteen (1.35%) of MS patients and 18 (3.6%) of the controls were diagnosed with cancer. The odds ratio of having cancer in patients with MS compared to the control group was 0.389 (95% CI = 0.161-0.940, p < 0.05).

DISCUSSION

There was no statistically significant difference in age, gender, tobacco smoking, and BMI between the groups after propensity score matching. The odds of having cancer were lower in our MS patients compared to the controls. The autoimmune changes responsible for the pathogenesis of MS may be responsible for the decrease in cancer risk.

Environmental Influences on Risk and Disease Course in Pediatric Multiple Sclerosis

Pediatric multiple sclerosis (MS) accounts for 3%-10% of all patients diagnosed with MS. Complex interplay between environmental factors impacts the risk for MS and may also affect disease course. Many of these environmental factors are shared with adult-onset MS. However, children with MS are in closer temporal proximity to the biological onset of MS and have less confounding environmental exposures than their adult counterparts. Environmental factors that contribute to MS risk include: geographical latitude, viral exposures, obesity, vitamin deficiencies, smoking, air pollution, perinatal factors, gut microbiome, and diet. More recently, research efforts have shifted to studying the impact of these risk determinants on the clinical course of MS. In this article we will examine relevant environmental risk determinants of pediatric MS and review the current knowledge on how these factors may contribute to pediatric MS disease evolution.

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.

Platelets and platelet-derived vesicles as an innovative cellular and subcellular platform for managing multiple sclerosis

INTRODUCTION

Multiple sclerosis (MS) is a progressive inflammatory autoimmune disease that involves young individuals. The drug delivery systems now are available for this disease have chronic and non-targeted effects on the patients. Because of the presence of BBB (blood-brain-barrier), their concentration in the CNS (central nervous system) is low. Because of this flaw, it is critical to use innovative active targeted drug delivery methods.

RESULT

Platelets are blood cells that circulate freely and play an important role in blood hemostasis. In this review, we emphasize the various roles of activated platelets in the inflammatory condition to recruit other cells to the injured area and limit inflammation. Besides, the activated platelets in the different stages of the MS disease play a significant role in limiting the progression of inflammation in the peripheral area and CNS.

DISCUSSION

This evidence indicates that a platelet-based drug delivery system can be an efficient biomimetic candidate for drug targeting to the CNS and limiting the inflammation in the peripheral and central areas for MS therapy.

Potential Utility of Natural Products against Oxidative Stress in Animal Models of Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune-mediated degenerative disease of the central nervous system (CNS) characterized by immune cell infiltration, demyelination and axonal injury. Oxidative stress-induced inflammatory response, especially the destructive effect of immune cell-derived free radicals on neurons and oligodendrocytes, is crucial in the onset and progression of MS. Therefore, targeting oxidative stress-related processes may be a promising preventive and therapeutic strategy for MS. Animal models, especially rodent models, can be used to explore the in vivo molecular mechanisms of MS considering their similarity to the pathological processes and clinical signs of MS in humans and the significant oxidative damage observed within their CNS. Consequently, these models have been used widely in pre-clinical studies of oxidative stress in MS. To date, many natural products have been shown to exert antioxidant effects to attenuate the CNS damage in animal models of MS. This review summarized several common rodent models of MS and their association with oxidative stress. In addition, this review provides a comprehensive and concise overview of previously reported natural antioxidant products in inhibiting the progression of MS.

FutureMS cohort profile: a Scottish multicentre inception cohort study of relapsing-remitting multiple sclerosis

PURPOSE

Multiple sclerosis (MS) is an immune-mediated, neuroinflammatory disease of the central nervous system and in industrialised countries is the most common cause of progressive neurological disability in working age persons. While treatable, there is substantial interindividual heterogeneity in disease activity and response to treatment. Currently, the ability to predict at diagnosis who will have a benign, intermediate or aggressive disease course is very limited. There is, therefore, a need for integrated predictive tools to inform individualised treatment decision making.

PARTICIPANTS

Established with the aim of addressing this need for individualised predictive tools, FutureMS is a nationally representative, prospective observational cohort study of 440 adults with a new diagnosis of relapsing-remitting MS living in Scotland at the time of diagnosis between May 2016 and March 2019.

FINDINGS TO DATE

The study aims to explore the pathobiology and determinants of disease heterogeneity in MS and combines detailed clinical phenotyping with imaging, genetic and biomarker metrics of disease activity and progression. Recruitment, baseline assessment and follow-up at year 1 is complete. Here, we describe the cohort design and present a profile of the participants at baseline and 1 year of follow-up.

FUTURE PLANS

A third follow-up wave for the cohort has recently begun at 5 years after first visit and a further wave of follow-up is funded for year 10. Longer-term follow-up is anticipated thereafter.

The Economic Burden of Multiple Sclerosis in the United States: Estimate of Direct and Indirect Costs

BACKGROUND AND OBJECTIVES

A recent report estimated that approximately 1 million adults were living with multiple sclerosis (MS) in the United States. Although MS is rarely the direct cause of death, its debilitating effects on normal body functions can result in considerable disruption to daily living and life roles including work, physical independence, mobility, social interaction, and participation in leisure activities. This study estimated the total economic burden of MS in the United States in 2019.

METHODS

This study used a prevalence-based approach to estimate the national economic burden of MS. Claims from 3 sources (Medicare Current Beneficiary Survey, Medicare Standard Analytical File, and Optum de-identified Normative Health Information System) were used to obtain direct costs and a survey was developed to collect indirect costs (e.g., labor market productivity losses, costs of paid and unpaid caregivers, home modification) from 946 patients with MS (PwMS). Direct medical costs reflected the difference in the total average annual amount paid for PwMS vs matched controls without MS. Future earnings loss due to premature death attributable to MS was calculated using Centers for Disease Control and Prevention mortality data and Medicare claims data.

RESULTS

The estimated total economic burden was $85.4 billion, with a direct medical cost of $63.3 billion and indirect and nonmedical costs of $22.1 billion. Retail prescription medication (54%); clinic-administered drugs, medication, and administration (12%); and outpatient care (9%) were the 3 largest components of the direct costs. The average excess per-person annual medical costs for PwMS was $65,612; at $35,154 per person, disease-modifying therapies (DMTs) accounted for the largest proportion of this cost. The cost per DMT user ranged from $57,202 to $92,719, depending on sex-age strata. The average indirect and nonmedical costs were $18,542 per PwMS and $22,875 per PwMS if caregivers' costs were included. Lost earnings due to premature death, presenteeism, and absenteeism losses were the largest indirect cost components.

DISCUSSION

MS is a costly chronic disease, with direct costs of prescription drugs and indirect productivity loss being important cost drivers. Our findings suggested that the burden of MS in the United States has been underestimated.

Synthesis and Evaluation of Serinolamide Derivatives as Sphingosine-1-Phosphate-1 (S1P1) Receptor Agonists

Sphingosine-1-phosphate-1 (S1P₁) receptor agonists are well-known drugs for treating multiple sclerosis (MS) caused by autoreactive lymphocytes that attack the myelin sheath. Therefore, an effective therapeutic strategy is to reduce the lymphocytes in the blood by inducing S1P₁ receptor internalization. We synthesized serinolamide A, a natural product of the sea, and performed S1P₁ receptor internalization assay to evaluate functionally antagonistic S1P₁ receptor agonist activity. In order to synthesize derivatives with better efficacy than serinolamide A and B, new derivatives were synthesized by introducing the phenyl ring moiety of fingolimod. Among them, compounds 19 and 21 had superior S1P₁ agonistic effects to serinolamide. We also confirmed that compound 19 effectively inhibited lymphocyte outflow in peripheral lymphocyte count (PLC) assay.

A Final Frontier in Environment-Genome Interactions? Integrated, Multi-Omic Approaches to Predictions of Non-Communicable Disease Risk

Epidemiological and associative research from humans and animals identifies correlations between the environment and health impacts. The environment—health inter-relationship is effected through an individual’s underlying genetic variation and mediated by mechanisms that include the changes to gene regulation that are associated with the diversity of phenotypes we exhibit. However, the causal relationships have yet to be established, in part because the associations are reduced to individual interactions and the combinatorial effects are rarely studied. This problem is exacerbated by the fact that our genomes are highly dynamic; they integrate information across multiple levels (from linear sequence, to structural organisation, to temporal variation) each of which is open to and responds to environmental influence. To unravel the complexities of the genomic basis of human disease, and in particular non-communicable diseases that are also influenced by the environment (e.g., obesity, type II diabetes, cancer, multiple sclerosis, some neurodegenerative diseases, inflammatory bowel disease, rheumatoid arthritis) it is imperative that we fully integrate multiple layers of genomic data. Here we review current progress in integrated genomic data analysis, and discuss cases where data integration would lead to significant advances in our ability to predict how the environment may impact on our health. We also outline limitations which should form the basis of future research questions. In so doing, this review will lay the foundations for future research into the impact of the environment on our health.

Impact of IL-21 Gene Polymorphisms (rs2055979) and the Levels of Serum IL-21 on the Risk of Multiple Sclerosis

Multiple sclerosis (MS) is a chronic autoimmune disorder of the central nervous system. Genetic and environmental factors have important roles in the induction, onset, and progression of MS. In this study, the IL-21 genotype (rs2055979) (G/T) in Iraqi MS patients was compared with a healthy control group to investigate the possible association of any particular genotype or allele with multiple sclerosis. This study included 70 patients with relapsing-remitting MS and 50 healthy individuals as control. Following the extraction of genomic DNA, polymerase chain reaction-restriction fragment length polymorphism, the frequencies of genotypes, and alleles were calculated and statistically analyzed. The results of the study revealed a significant reduction in the distribution of the wild homozygous genotype (GG) in MS patients, in comparison to a healthy control group (14.3% vs. 34 %; 0.0129 at P≤0.05; odds ratio [OR] 3.0909, 95% confidence interval [CI]: 1.2704-7.5203). However, MS cases and controls did not differ significantly in neither GT nor TT genotypes, 62.9% (OR 0.6402, 95% CI: 0.3064-1.3374) and 52% (OR 0.5494, 95% CI: 0.2074-1.4557), respectively. The data of allele frequencies in patients and controls showed that the G allele frequencies were 0.46 vs. 0.60 in patients and controls, respectively, while T allele frequencies were 0.54 vs. 0.40 in patients and controls, respectively. The current conclusions indicated that in the study group, the GG genotype of IL-21(rs2055979) could be related to MS.

Discovery of Novel Sphingosine-1-Phosphate-1 Receptor Agonists for the Treatment of Multiple Sclerosis

The sphingosine-1-phosphate-1 (S1P₁) receptor agonists have great potential for the treatment of multiple sclerosis (MS) because they can inhibit lymphocyte egress through receptor internalization. We designed and synthesized triazole and isoxazoline derivatives to discover a novel S1P₁ agonist for MS treatment. Of the two scaffolds, the isoxazoline derivative was determined to have excellent in vitro efficacy and drug-like properties. Among them, compound 21l was found to have superior drug-like properties as well as excellent in vitro efficacies (EC₅₀ = 7.03 nM in β-arrestin recruitment and EC₅₀ = 11.8 nM in internalization). We also confirmed that 21l effectively inhibited lymphocyte egress in the peripheral lymphocyte count test and significantly improved the clinical score in the experimental autoimmune encephalitis MS mouse model.

Incidence of Pediatric Multiple Sclerosis in Iran within 2000-2019

OBJECTIVES

Due to a lack of data on pediatric multiple sclerosis (MS) epidemiology in Iran, this study aimed to determine the incidence rate of pediatric MS in Iran.

MATERIALS & METHODS

 All the data of the patients with MS registered in the Ministry of Health and Medical Education of Iran for 20 years were collected in this study; those born in 1982 and diagnosed with the disease and treated since 2000 were included in this study. Therefor The collected variables were patients' age at the time of diagnosis, gender, year of diagnosis, urban or rural residency, and province of residence. Additionally, age-specific incidence rates per 100,000 of the population were calculated.

RESULTS

This study was performed on 4544 cases of pediatric MS within 2000-2019, of which 997 patients (21.9%) were male. The mean age of the patients with MS at the time of diagnosis was 14.3±4.6 years, and 4414 children (97.1%) lived in urban areas. The incidence rate of pediatric MS in Iran during 20 years increased from 0.26 per 100,000 of the population in 2000 to 1.53 in 2019.

CONCLUSION

The incidence of pediatric MS in Iran is high, and the development of diagnostic practices in the past decade in Iran has contributed to the detection of this high incidence.

Prevalence of Anxiety and Depression in Patients With Multiple Sclerosis in Saudi Arabia: A Cross-Sectional Study

Introduction

Multiple sclerosis (MS) is a chronic disease of progressive demyelination in the central nervous system and carries a significant risk for depression and other psychological difficulties associated with low quality of life. There is a paucity of data on the prevalence of anxiety and depression in Saudi Arabia among patients with MS. We conducted a cross-sectional study to determine the prevalence of anxiety and depression in Saudi Arabia among patients with MS by age, disease severity, compliance to medication, and social support.

Methods

This cross-sectional study measured the prevalence of anxiety and depression in 184 adult patients with MS. The patients were selected through a random sampling method from a pool of MS societies in Saudi Arabia. The participants completed self-administered questionnaires that included demographic variables. The participants also completed the Patient Health Questionnaire-9 (PHQ-9) and the General Anxiety Disorder-7 (GAD-7) questionnaire.

Results

Depression was detected among 139 (75.5%) patients with MS, with most participants having mild depression (31%). More women (83.1%) experienced depression than men (62.1%; p = 0.002). Anxiety disorder was present in 123 (66.8%) patients with MS, and most had mild anxiety (n = 56; 30.4%).

Conclusion

We found a very high rate of depression and anxiety among patients with MS in Saudi Arabia. Our results highlight the need for periodic screening and examination of patients with MS by psychiatrists to facilitate the early detection and treatment of these comorbidities, potentially improving patient quality of life and health outcomes.

Scavenging the hidden impacts of non-coding RNAs in multiple sclerosis

Multiple sclerosis (MS) is a chronic neuroinflammatory disease that causes severe neurological dysfunction leading to disabilities in patients. The prevalence of the disease has been increasing gradually worldwide, and the specific etiology behind the disease is not yet fully understood. Therapies aimed against treating MS patients have been growing lately, intending to delay the disease progression and increase the patients' quality of life. Various pathways play crucial roles in developing the disease, and several therapeutic approaches have been tackling those pathways. However, these strategies have shown several side effects and inconsistent efficacy. MicroRNAs (miRNAs), long noncoding RNAs (lncRNAs), and circular RNAs (circRNAs) have been shown to act as key players in various disease pathogenesis and development. Several proinflammatory and anti-inflammatory miRNAs have been reported to participate in the development of MS. Hence, the review assesses the role of miRNAs, lncRNAs, and circRNAs in regulating immune cell functions better to understand their impact on the molecular mechanics of MS.

Role of environmental factors in multiple sclerosis

INTRODUCTION

Environmental factors play a significant role in the pathogenesis and progression of multiple sclerosis (MS), either acting alone or by interacting with other environmental or genetic factors. This cumulative exposure to external risk factors is highly complex and highly variable between individuals.

AREAS COVERED

We narratively review the current evidence on the role of environment-specific risk factors in MS onset and progression, as well as the effect of gene-environment interactions and the timing of exposure We have reviewed the latest literature, by Ovid Medline, retrieving the most recently published systematic reviews and/or meta-analyses and more recent studies not previously included in meta-analyses or systematic reviews.

EXPERT OPINION

There is some good evidence supporting the impact of some environmental risk factors in increasing the risk of developing MS. Tobacco smoking, low vitamin D levels and/or low sun exposure, Epstein Barr Virus (EBV) seropositivity and a history of infectious mononucleosis may increase the risk of developing MS. Additionally, there is some evidence that gene-smoking, gene-EBV, and smoking-EBV interactions additively affect the risk of MS onset. However, the evidence for a role of other environmental factors in MS progression is limited. Finally, there is some evidence that tobacco smoking, insufficient vitamin D levels and/or sun exposure have impacts on MS phenotypes and various markers of disease activity including relapse, disability progression and MRI findings. Clearly the effect of environmental factors on MS disease course is an area that requires significantly more research.

Serum Vitamin D Level among Multiple Sclerosis Patients in the Tropics: Experience from a Private Clinic in Addis Ababa, Ethiopia

Background

Multiple sclerosis (MS) is an immune mediated disabling neurological disorder. Very little is known about MS in Ethiopia. The objective of this study was to determine the prevalence of hypovitaminosis D and associated factors in cohort of MS patients in Ethiopia.

Method

A cross-sectional observational study was conducted among 25 multiple sclerosis patients at Yehuleshet Specialty Clinic, Addis Ababa, Ethiopia.

Results

The prevalence of vitamin D deficiency was 96% (n=24). The average serum vitamin D was 14.8 (±10.4) ng/mL. The mean age was 35.8 (±10) years. Females accounted for 80% (n=20). Relapsing and remitting MS was the commonest variant. Motor, sensory, and mixed symptoms accounted for 40% (n=10), 20% (n=5), and 24% (n=6), respectively. Cold or hot weather and stress were reported as worsening factors in 24% (n=6). Relapse rate was 44% (n=11). Fatigue and seizure disorder were reported by 80% (n=20) and 16% (n=4) respectively. Steroid is the commonest prescribed medication for the patients. A negative correlation was found between serum vitamin D and age (r = -0.062, p = 0.7). Similarly, a negative association was observed between vitamin D and duration of illness (r = -0.311, p = 0.1). Fatigue was reported by those with moderate hypovitaminosis compared to those having severe hypovitaminosis (p=0.002). Seizure was reported more by those with vitamin D below 10ng/mL compared to those having above 10 ng/mL (p=0.004).

Conclusion

Our study demonstrates a high prevalence of hypovitaminosis D in Ethiopian MS patients. Hypovitaminosis D was associated with increment in age and duration of illness.

Air pollution and multiple sclerosis: a comprehensive review

Multiple sclerosis (MS) is an inflammatory, autoimmune demyelinating disorder of the central nervous system (CNS), leading to progressive functional impairments, and many intrinsic and acquired factors are believed to be associated with its development and relapse. In terms of environmental factors, air pollution has gained much attention during recent decades, as chronic exposure to ambient air pollution seems to increase the level of some pro-inflammatory markers in the human brain, which can lead to neuroinflammation, neurodegeneration, and blood-brain barrier (BBB) breakdown. These events may also be associated with the risk of MS development and relapse. In this review, we aimed to summarize recent findings around the impact of air pollutants, including particulate matter (PM10, PM2.5, and ultra-fine particles), gaseous pollutants (carbon monoxide [CO], nitrogen oxides [NO_x], sulfur dioxide [SO₂], and ozone [O₃]), and heavy metals, on MS development and relapse.

Air pollution and multiple sclerosis: a comprehensive review

Multiple sclerosis (MS) is an inflammatory, autoimmune demyelinating disorder of the central nervous system (CNS), leading to progressive functional impairments, and many intrinsic and acquired factors are believed to be associated with its development and relapse. In terms of environmental factors, air pollution has gained much attention during recent decades, as chronic exposure to ambient air pollution seems to increase the level of some pro-inflammatory markers in the human brain, which can lead to neuroinflammation, neurodegeneration, and blood-brain barrier (BBB) breakdown. These events may also be associated with the risk of MS development and relapse. In this review, we aimed to summarize recent findings around the impact of air pollutants, including particulate matter (PM10, PM2.5, and ultra-fine particles), gaseous pollutants (carbon monoxide [CO], nitrogen oxides [NO_x], sulfur dioxide [SO₂], and ozone [O₃]), and heavy metals, on MS development and relapse.

Association study of promoter polymorphisms of interferon alpha and beta receptor subunit 1 (IFNAR1) gene and therapeutic response to interferon-beta in patients with multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is an autoimmune disease described by inflammatory neuronal losses and resultant failures. The disease could abate by interferon-beta (IFN-β) therapy in MS patients. However, the drug response productivity is changeable between patients, and the accurate mechanism of action of the IFN-β is not obvious. The present study aims to investigate the role of interferon alpha and beta receptor subunit 1 (IFNAR1) promoter polymorphisms towards IFN-β treatment response in MS patients.

METHODS

The subjects herein were separated into either responder (n = 57) or non-responder (n = 43) groups according to IFN-β treatment and Expanded Disability Status Scale score. The Sanger sequencing method was used for genotyping.

RESULTS

Among nearly 64 Single Nucleotide Polymorphisms (SNPs), we found a significant association between the rs2850015 polymorphism and the responders and non-responders to IFN-β treatment in the recessive model of inheritance (P = 0.02). The results also revealed a significant change in the two groups of responders and non-responders to the treatment for rs36158718 as an Insertion/Deletion (INDEL) (P = 0.02). Moreover, bioinformatic analyses predicted a remarkable role for both rs2850015 and rs36158718 related to the changes of binding affinity of transcription factors and alterations in their alleles.

CONCLUSION

The present study results suggest that the genetic heterogeneity in the promoter region of IFNAR1 could affect the response to IFN-β. However, further studies with a larger sample size are needed to further demonstrate this relationship.

Differential disease phenotypes and progression in relapsing-remitting multiple sclerosis: comparative analyses of single Canadian and Saudi Arabian clinics

Objective

Relapsing–remitting multiple sclerosis (RR-MS) phenotypes differ widely although the variables contributing to this heterogeneity remain uncertain. To assess geographic and ethnic effects on RR-MS phenotypes, we investigated RR-MS patients in Canada and Saudi Arabia.

Methods

A retrospective analysis of patients followed in two MS Clinics was performed in Medina, Saudi Arabia and Edmonton, Canada. Demographic and clinical data were collected for each patient and analyzed using univariable and multivariable statistics. Univariable and multivariable linear regression were used to distinguish the significant clinical and demographic features and neurological systems associated with the change in expanded disability status scale (EDSS) between clinical assessments.

Results

Patients with treated RR-MS were recruited (n = 51, Saudi; n = 47, Canada) although the disease duration was longer in the Canadian cohort (5.6 ± 2.2 yr.) compared to the Saudi cohort (4.4 ± 1.4 yr.) (P < 0.05), annual relapse rate and EDSS change were higher in the Saudi cohort (P < 0.05). Infratentorial lesion-associated presentation differed (Canada, n = 23; Saudi, n = 13) among groups (P < 0.05). Spinal cord lesions on MRI were more frequently detected in Canadian (n = 23) compared to Saudi (n = 1) patients (P < 0.05). Patients within the Saudi cohort displayed a significantly greater change in Expanded Disability Status Scale (EDSS) between first and second assessments.

Conclusions

Despite differences in geographic location, ethnicity, and predominance of infratentorial lesions in the Canadian group, the RR-MS phenotypes were similar although the Saudi cohort displayed a more severe disease course.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02317-2.

NMOSD and MS prevalence in the Indigenous populations of Australia and New Zealand

BACKGROUND

We studied the prevalence of neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) in Indigenous populations of Australia and New Zealand with the aim of assessing potential differences.

METHODS

Cases of possible NMOSD and MS were collected from Australia and New Zealand. Clinical details, MR imaging, and serologic results were used to apply 2015 IPND diagnostic criteria for NMOSD and 2010 McDonald criteria for MS. Frequencies of self-determined ethnic ancestry were calculated for confirmed NMOSD, suspected NMOSD, and MS. Prevalence rates for NMOSD and MS according to ancestry were compared.

RESULTS

There were 75 cases with NMOSD, 89 with suspected NMSOD, and 101 with MS. NMOSD cases were more likely to have Asian, Indigenous, or Other ancestry compared to suspected NMOSD or MS. There were no differences in the clinical phenotype of NMOSD seen in Indigenous compared to European ancestry populations. Per 100,000, the prevalence estimate for NMOSD in people with Māori ancestry was 1.50 (95% CI 0.52-2.49) which was similar to those with Asian ancestry 1.57 (95% CI 1.15-1.98). NMOSD prevalence in Australian Aboriginal and Torres Strait Islander populations was 0.38 (95% CI 0.00-0.80) per 100,000.

CONCLUSION

The prevalence of NMOSD in the Māori population is similar to South East Asian countries, reflecting their historical origins. The prevalence of MS in this group is intermediate between those with South East Asian and European ancestry living in New Zealand. Both NMOSD and particularly MS appear to be uncommon in the Indigenous populations of Australia.

Enhancing Mood, Cognition, and Quality of Life in Pediatric Multiple Sclerosis

Pediatric-onset multiple sclerosis (POMS), representing approximately 5% of all MS cases, affects the central nervous system during its ongoing development. POMS is most commonly diagnosed during adolescence but can occur in younger children as well. For pediatric patients with MS, it is critical to manage the full impact of the disease and monitor for any effects on school and social functioning. Disease management includes not only disease-modifying therapies but also strategies to optimize wellbeing. We review the interventions with the highest evidence of ability to improve the disease course and quality of life in POMS. High levels of vitamin D and a diet low in saturated fat are associated with lower relapse rates. Exercise ameliorates fatigue and sleep. Behavioral strategies for sleep hygiene and mood regulation can also improve fatigue and perceived health. POMS management should be addressed holistically, including assessing overall symptom burden as well as the psychological and functional impact of the disease.

HSV-1 and Endogenous Retroviruses as Risk Factors in Demyelination

Herpes simplex virus type 1 (HSV-1) is a neurotropic alphaherpesvirus that can infect the peripheral and central nervous systems, and it has been implicated in demyelinating and neurodegenerative processes. Transposable elements (TEs) are DNA sequences that can move from one genomic location to another. TEs have been linked to several diseases affecting the central nervous system (CNS), including multiple sclerosis (MS), a demyelinating disease of unknown etiology influenced by genetic and environmental factors. Exogenous viral transactivators may activate certain retrotransposons or class I TEs. In this context, several herpesviruses have been linked to MS, and one of them, HSV-1, might act as a risk factor by mediating processes such as molecular mimicry, remyelination, and activity of endogenous retroviruses (ERVs). Several herpesviruses have been involved in the regulation of human ERVs (HERVs), and HSV-1 in particular can modulate HERVs in cells involved in MS pathogenesis. This review exposes current knowledge about the relationship between HSV-1 and human ERVs, focusing on their contribution as a risk factor for MS.

Epidemiology, treatment patterns and healthcare utilizations in multiple sclerosis in Taiwan

“Real-world” data on the nationwide epidemiology and treatment patterns of multiple sclerosis (MS) is very scarce in Asia. This study is aim to evaluate the 10-years trends in epidemiology and treatment patterns of MS with Taiwan’s National Health Insurance Database (NHIRD). Patients aged 20 years or older and were newly diagnosed with MS between 2007 and 2016 were identified. The crude incidences of MS were presented annually and stratified by sex and age. Baseline characteristics and treatment patterns, particularly disease-modifying drugs (DMDs), were also analyzed. This study included 555 MS patients (mean age was 36.9 and 74.4% were female). The crude incidence rate of MS decreased slightly from 0.43 per 100,000 persons in 2007 to 0.24 per 100,000 persons in 2015. The female to male ratios remained mainly between 2 to 3. Approximately 80% of MS patients received initial DMDs, with interferon β-1a as the dominant one. Furthermore, 37.5% of MS patients received subsequent DMDs, with fingolimod being the most frequently used. The median times from diagnosis to initial and to subsequent DMDs were 77 and 1239 days, respectively. This nationwide study provides up-to-date and sophisticated estimates of MS epidemiology and treatment pattern in “real-world” setting in Taiwan.

The Putative Adverse Effects of Bisphenol A on Autoimmune Diseases

Bisphenol A (BPA) is a monomer that is widely used in the manufacture of polycarbonate plastics including storage plastics and baby bottles, and is considered one of the most widely used synthetic compounds in the manufacturing industry. Exposure to BPA mainly occurs after oral ingestion and results from leaks into food and water from plastic containers and according to epidemiological data exposure is widespread and estimated to occur in 90% of individuals. BPA exertspleiotropiceffects and demonstrates estrogen like effects, thus considered an endocrine disrupting chemical. Growing body of evidence highlight the role of BPA in modulating immune responses and signaling pathways resulting in a proinflammatory response by enhancing the differential polarization of immune cells and cytokine production profile to one that is consistent with proinflammation. Indeed, epidemiological studies have uncovered associations between several autoimmune diseases and BPA exposure. Data from animal models provided consistent evidence highlighting the role of BPA in the pathogenesis, exacerbation and perpetuation of various autoimmune phenomena including neuroinflammation in the context of multiple sclerosis, colitis in inflammatory bowel disease, nephritis in systemic lupus erythematosus, and insulitis in type 1 diabetes mellitus. Given the wide spread of BPA use and its effects in immune systemdysregulation, a call for careful assessment of patients' risks and for public health measures are needed to limit exposure and subsequent deleterious effects. The purpose of this paper is to explore the autoimmune triggering mechanisms and present the current literature supporting the role of BPA in the pathogenesis of autoimmune diseases.

Tryptamine Attenuates Experimental Multiple Sclerosis Through Activation of Aryl Hydrocarbon Receptor

Tryptamine is a naturally occurring monoamine alkaloid which has been shown to act as an aryl hydrocarbon receptor (AHR) agonist. It is produced in large quantities from the catabolism of the essential amino acid tryptophan by commensal microorganisms within the gastrointestinal (GI) tract of homeothermic organisms. Previous studies have established microbiota derived AHR ligands as potent regulators of neuroinflammation, further defining the role the gut-brain axis plays in the complex etiology in multiple sclerosis (MS) progression. In the current study, we tested the ability of tryptamine to ameliorate symptoms of experimental autoimmune encephalomyelitis (EAE), a murine model of MS. We found that tryptamine administration attenuated clinical signs of paralysis in EAE mice, decreased the number of infiltrating CD4⁺ T cells in the CNS, Th17 cells, and RORγ T cells while increasing FoxP3+Tregs. To test if tryptamine acts through AHR, myelin oligodendrocyte glycoprotein (MOG)-sensitized T cells from wild-type or Lck-Cre AHR^flox/flox mice that lacked AHR expression in T cells, and cultured with tryptamine, were transferred into wild-type mice to induce passive EAE. It was noted that in these experiments, while cells from wild-type mice treated with tryptamine caused marked decrease in paralysis and attenuated neuroinflammation in passive EAE, similar cells from Lck-Cre AHR^flox/flox mice treated with tryptamine, induced significant paralysis symptoms and heightened neuroinflammation. Tryptamine treatment also caused alterations in the gut microbiota and promoted butyrate production. Together, the current study demonstrates for the first time that tryptamine administration attenuates EAE by activating AHR and suppressing neuroinflammation.

Interferons and Multiple Sclerosis: Lessons from 25 Years of Clinical and Real-World Experience with Intramuscular Interferon Beta-1a (Avonex)

Recombinant interferon (IFN) β-1b was approved by the US Food and Drug Administration as the first disease-modifying therapy (DMT) for multiple sclerosis (MS) in 1993. Since that time, clinical trials and real-world observational studies have demonstrated the effectiveness of IFN therapies. The pivotal intramuscular IFN β-1a phase III trial published in 1996 was the first to demonstrate that a DMT could reduce accumulation of sustained disability in MS. Patient adherence to treatment is higher with intramuscular IFN β-1a, given once weekly, than with subcutaneous formulations requiring multiple injections per week. Moreover, subcutaneous IFN β-1a is associated with an increased incidence of injection-site reactions and neutralizing antibodies compared with intramuscular administration. In recent years, revisions to MS diagnostic criteria have improved clinicians' ability to identify patients with MS and have promoted the use of magnetic resonance imaging (MRI) for diagnosis and disease monitoring. MRI studies show that treatment with IFN β-1a, relative to placebo, reduces T2 and gadolinium-enhancing lesions and gray matter atrophy. Since the approval of intramuscular IFN β-1a, a number of high-efficacy therapies have been approved for MS, though the benefit of these high-efficacy therapies should be balanced against the increased risk of serious adverse events associated with their long-term use. For some subpopulations of patients, including pregnant women, the safety profile of IFN β formulations may provide a particular benefit. In addition, the antiviral properties of IFNs may indicate potential therapeutic opportunities for IFN β in reducing the risk of viral infections such as COVID-19.

Association of Multiple Sclerosis with PM 2.5 levels. Further evidence from the highly polluted area of Padua Province, Italy

BACKGROUND

Fifty years of epidemiological survey and intra-regional differences in prevalence suggest that environmental factors may be associated with increased multiple sclerosis (MS) risk in Northern Italy. Based on the findings of a previous study carried out in the highly polluted Padan Plain, we further explored the relationship between PM2.5 levels and MS prevalence by comparing bordering areas characterized by quite different environmental conditions, namely the Municipality of Padua and the special protected zone (SPZ) of the Euganean Hills Regional Park, located 15 km from the City.

METHODS

Three territories were identified; 1) the SPZ, extending over an area of 15.096 hectares and having a total population of 23,980 inhabitants, 2) the urban area of Padua, with a total population of 210,440 inhabitants and repeatedly recognized by the European Invironmental Agency as one of the most polluted Cities of Europe, 3) the Intermediate Zone (IZ), i.e., the area in between the previous two, including part of the urban territories of eight villages adjacent to the SPZ. Demographic and socio-economical data were obtained from official government sources (www.istat.it and www.regione.veneto.it). All Italian MS patients residing in these three areas on December 31, 2018, were registered. PM2.5 concentrations (annual average 1998-2018, μg/m3) were measured by satellite. The correlation between PM2.5 concentrations and MS prevalence was analysed.

RESULTS

MS prevalence was significantly higher in Padua City (265/100.000) compared to both the SPZ of the Euganean Hills Park (160/100,000; p < 0.0001) and the IZ (194.4/100,000). Prevalence strongly associated with the annual average concentration of PM2.5 (r = 0.89 p < 0.00001).

CONCLUSION

In the Province of Padua, one of the most polluted areas of Europe, MS prevalence is strongly associated with PM2.5 exposure. Our findings suggest that air pollutants may be one of the possible environmental risk factors for MS in the Veneto Region of Italy.

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

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

Search for viral agents in cerebrospinal fluid in patients with multiple sclerosis using real-time PCR and metagenomics

Multiple sclerosis (MS) is a chronic, immune-mediated demyelinating disease of the central nervous system of unclear etiology, but there is some evidence that viral infections could be responsible for triggering autoimmune mechanisms against myelin. We searched for viral RNA and DNA in cerebrospinal fluid (CSF) of 34 MS patients and 13 controls using RT-PCR/PCR against common neurotropic viruses. In addition, shotgun DNA- and RNA-based metagenomics were done in 13 MS patients and 4 controls. Specific quantitative real-time RT-PCR/PCR testing revealed the presence of viral nucleic acid in seven (20.59%) MS patients and in one (7.69%) control patient. In MS patients the most frequently detected was human herpesvirus type 6 (HHV-6; 3 cases; 8.82%); followed by Epstein-Barr virus (EBV; 2 cases; 5.88%), varicella zoster virus (VZV; 1 case; 2.94%) and Enterovirus (EV; 1 case; 2.94%). The single identified virus among controls was EBV (7.69%). DNA and RNA metagenomic assays did not identify any known eukaryotic viruses even though three of the analyzed samples were low-level positive by specific quantitative real-time PCR. In conclusion, we detected the presence of Herpesviridae and occasionally Enteroviridae in CSF from patients with MS but their prevalence was not significantly higher than among controls. Metagenomic analysis seems to be less sensitive than real-time RT-PCR/PCR and it did not detect any potential viral pathogens.

Stressful life events are associated with the risk of multiple sclerosis

BACKGROUND AND PURPOSE

Unexpected stressful life events may alter immune function and affect susceptibility to autoimmune diseases including multiple sclerosis (MS). Current results from epidemiological investigations examining the role of stress in MS remain inconsistent. The aim was to conduct the hitherto largest population-based case-control study on this topic.

METHODS

Extensive questionnaire information collected on lifestyle environmental factors available for 2930 incident MS cases and 6170 controls were used to assess the association of 10 major life events that had occurred before disease onset with the risk of MS by unconditional logistic regressions, adjusting for potential confounders. Stratified analyses were also performed by sex and time.

RESULTS

Compelling evidence was found for a link between major life events and risk of MS - most events significantly increased disease risk by 17%-30%. It was further observed that women were affected to a greater extent than men under certain stressful scenarios, and that most events that happened recently (≤5 years prior to MS onset) had significant effects on MS, indicating a critical window in disease development.

CONCLUSION

Stressful life events may have an adverse effect on the risk of MS. Research into the mechanisms of this observation may give important clues to triggering pathogenetic events in MS.

Role of Smoking in the Pathogenesis of Multiple Sclerosis: A Review Article

Multiple sclerosis (MS) is a complex and unpredictable neurological condition. It is the most commonly seen autoimmune disorder. The incidence of disease and its prevalence are growing worldwide. Early identification of the disease and accurate diagnosis is important to prevent further complications and disability. The etiology remains unclear, and it is believed that complex gene-environment interactions play an essential role. Genetic predisposition only describes a portion of the disease risk, whereas lifestyle and environmental factors are significant contributors. Smoking was identified as an important risk factor for MS. The main objectives of this review were to examine the underlying mechanisms of immune dysregulation in the development of MS, explore the association between smoking and MS, and identify other genetic and environmental factors that alter the risk of developing the disease. We searched PubMed for articles relevant to the study topic published between 2000 and 2020 using the search terms "multiple sclerosis," "cigarette smoking," "risk factors," and, "epigenetics." Studies reveal a marked association between smoking and the risk of MS. Unlike genetic risk factors, many lifestyles and environmental factors can be adjusted, with potential for prevention, particularly for people at the highest risk, such as families of individuals with MS.

Changes in Amino Acid and Acylcarnitine Plasma Profiles for Distinguishing Patients with Multiple Sclerosis from Healthy Controls

McDonald criteria and magnetic resonance imaging (MRI) are used for the diagnosis of multiple sclerosis (MS); nevertheless, it takes a considerable amount of time to make a clinical decision. Amino acid and fatty acid metabolic pathways are disturbed in MS, and this information could be useful for diagnosis. The aim of our study was to find changes in amino acid and acylcarnitine plasma profiles for distinguishing patients with multiple sclerosis from healthy controls. We have applied a targeted metabolomics approach based on tandem mass-spectrometric analysis of amino acids and acylcarnitines in dried plasma spots followed by multivariate statistical analysis for discovery of differences between MS (n = 16) and control (n = 12) groups. It was found that partial least square discriminant analysis yielded better group classification as compared to principal component linear discriminant analysis and the random forest algorithm. All the three models detected noticeable changes in the amino acid and acylcarnitine profiles in the MS group relative to the control group. Our results hold promise for further development of the clinical decision support system.

The Role of Herpes Simplex Virus Type 1 Infection in Demyelination of the Central Nervous System

Herpes simplex type 1 (HSV-1) is a neurotropic virus that infects the peripheral and central nervous systems. After primary infection in epithelial cells, HSV-1 spreads retrogradely to the peripheral nervous system (PNS), where it establishes a latent infection in the trigeminal ganglia (TG). The virus can reactivate from the latent state, traveling anterogradely along the axon and replicating in the local surrounding tissue. Occasionally, HSV-1 may spread trans-synaptically from the TG to the brainstem, from where it may disseminate to higher areas of the central nervous system (CNS). It is not completely understood how HSV-1 reaches the CNS, although the most accepted idea is retrograde transport through the trigeminal or olfactory tracts. Once in the CNS, HSV-1 may induce demyelination, either as a direct trigger or as a risk factor, modulating processes such as remyelination, regulation of endogenous retroviruses, or molecular mimicry. In this review, we describe the current knowledge about the involvement of HSV-1 in demyelination, describing the pathways used by this herpesvirus to spread throughout the CNS and discussing the data that suggest its implication in demyelinating processes.

Rapamycin and MCC950 modified gut microbiota in experimental autoimmune encephalomyelitis mouse by brain gut axis

AIMS

Multiple sclerosis (MS) whose pathogenesis is still unclear is a chronic progressive disease in the central nervous system. Gut microbiota can directly or indirectly affect the immune system through the brain gut axis to engage in the occurrence and development of the disease.

MATERIALS AND METHODS

C57BL/6 mice which were immunized by MOG_35-55 to prepare experimental autoimmune encephalomyelitis (EAE) animal models were treated with rapamycin and MCC950 (CP-456773) in combination or separately. After sequencing the 16S rRNA V4 region of gut microbiota, the species, abundance and composition of gut microbiota were analyzed by Alpha diversity, Bata diversity and LEfSe analysis. The pathological changes and the expression of CD4 and CD8 of brain, large intestine and spleen were detected.

KEY FINDINGS

The results showed that rapamycin and MCC950 could alleviate the progression of the disease by inducing autophagy and inhibiting the immune response. The Alpha diversity of EAE model group was no significant difference compering to control group while the number of OTUs was decreased. After the treatment by rapamycin and MCC950, the abundance and composition of gut microbiota was relatively recovered, which was close to that of normal mice.

SIGNIFICANCE

Inhibiting immune cell-mediated inflammation and restoring the composition of gut microbiota may help to alleviate the clinical symptoms of multiple sclerosis. Furthermore, to research the regulatory effect between immune response and gut microbiota may be a new strategy for the prevention and treatment of multiple sclerosis.

Smoking Cessation Considerations for People with Multiple Sclerosis

Background:

Comprehensive care of people with multiple sclerosis integrates disease modifying therapy, symptom management and minimization of risk factors for disease progression. Cigarette smoking is a modifiable risk factor associated with development and progression of disease and increased disability. However, little is known about specific factors that affect smoking cessation in patients with multiple sclerosis or how to integrate smoking cessation into specialized multiple sclerosis care.

Methods:

Twenty-nine active smokers with multiple sclerosis were surveyed at the James Q. Miller Multiple Sclerosis clinic at the University of Virginia Health. Demographics, smoking history, multiple sclerosis history, interest in quitting, barriers to quitting and cessation modalities of interest were collected, specifically interest in working with a clinical pharmacist for cessation.

Results:

Seventy-six percent of individuals believed that there was no relationship between smoking and MS diagnosis and 52% were unaware of any relationship between smoking and disease progression. Less than half of patients (41%) reported receiving counseling from a primary care physician or neurologist about the importance of smoking cessation. Common barriers to quitting included enjoyment of smoking (76%) and cravings (55%). Seventy-six percent of patients expressed interest in utilizing pharmacotherapy and 37% were interested in working closely with a clinical pharmacist.

Conclusions:

It is critical that providers caring for patients with multiple sclerosis assess smoking status and educate smokers about the relationship between smoking and disease progression. Efforts should be made to better understand patient-specific barriers to quitting and preferred methods of treatment, including pharmacotherapy and behavioral therapy. A multidisciplinary approach to smoking cessation that includes a clinical pharmacist may aid in the development of individualized care plans with frequent monitoring to improve patient success.

Perspectives of People with Multiple Sclerosis About Helminth Immunotherapy

Background

Due to the chronic and incurable nature of the autoimmune disease multiple sclerosis (MS), some people with MS will seek out alternative therapeutic approaches. Helminth immunotherapy, the deliberate inoculation with helminthic parasites as an intervention to prevent, delay, or minimize progression of autoimmune disorders, is one such approach gaining traction in academic research and with the public. Herein, we explored the perspectives of people with MS regarding helminth immunotherapy and its use in disease management.

Methods

Interpretive description, a qualitative research approach, was applied to data extracted from online forums. Multiple investigators independently identified, extracted, and analyzed data to develop preliminary codes. Inductive thematic analysis and triangulation were then used to collaboratively establish themes.

Results

Four main themes were generated: experience of living with MS, influential factors in contemplating helminth immunotherapy, logistics of helminth immunotherapy, and concerns about helminth immunotherapy.

Conclusions

There was a general consensus in publicly available online forums that conventional therapies do not provide meaningful improvement for some people with MS. These people may seek alternative therapies such as helminth immunotherapy. Information on helminth immunotherapy from internet resources (eg, blogs and social media forums) can contain biased and scientifically unsupported opinions. Messages of efficacy and improved quality of life are readily available and may influence people with MS considering helminth immunotherapy as an alternative therapy. Although some people with MS are seeking helminth immunotherapy, clinical trial data do not currently support its use for people with MS.

Relationship between miR-155 and miR-146a polymorphisms and susceptibility to multiple sclerosis in an Egyptian cohort

Multiple sclerosis (MS) is an autoimmune disorder of the central nervous system. It was previously demonstrated that miR-155 and miR-146a served a vital role in the pathophysiology of MS, and single nucleotide polymorphisms in miR-155 and miR-146a were found to be associated with the susceptibility to different autoimmune diseases, such as systemic lupus erythematosus, rheumatoid arthritis and type I diabetes. The aim of the present study was to analyze the association between susceptibility to MS and two genetic polymorphisms (miR-155 rs767649 A>T and miR-146a rs57095329 A>G) in a cohort of Egyptian patients. The presence of the two polymorphisms were analyzed in 114 patients with MS and 152 healthy controls using quantitative PCR. The present study demonstrated for the first time that: The TT genotype and T allele in miR-155 (rs767649 A>T) polymorphism were associated with an increased risk of MS; the miR-146a (rs57095329 A>G) mutated G allele conferred protection against the development of MS in all genetic models; miR-155 rs767649 A>T was a risk associated polymorphism of MS in females, but not in males; and miR-155 rs767649 AT/TT and miR-146a rs57095329 GG genotypes showed significantly higher distributions among patients with higher Expanded Disability Status Scale scores and secondary progressive MS subgroups. Therefore, miR-155 rs767649 polymorphism may confer susceptibility to MS, whereas miR-146a rs57095329 may be protective against MS in an Egyptian cohort.