Vitamin D supplementation for patients with multiple sclerosis treated with interferon-beta: a randomized controlled trial assessing the effect on flu-like symptoms and immunomodulatory properties

Nutritional interventions as modulators of the disease activity for idiopathic inflammatory myopathies: a scoping review

Idiopathic inflammatory myopathies (IIMs) are chronic, autoimmune connective tissue diseases associated with significant morbidity and disability. Nutrients can activate the immune system and contribute to chronic low-grade inflammation (LGI). Chronic muscle inflammation leads to imbalanced pro-inflammatory and anti-inflammatory cytokines, causing inadequate nutrition, weight loss and muscle weakness during a negative cycle. Owing to its potential to modulate LGI in various diseases, the Mediterranean diet (Med Diet) has been extensively studied. This scoping review explores the nutritional implications and recommendations of the Med Diet as a treatment for immune-mediated diseases, focusing on the gaps in IIM nutritional interventions. A comprehensive literature search of the MEDLINE and EBSCO databases between September 2018 and December 2022 was performed. We identified that the Med Diet and its specific components, such as omega-3 (nω3) fatty acids, vitamin D and antioxidants, play a role in the dietary treatment of connective tissue-related autoimmune diseases. Nutritional interventions have demonstrated potential for modulating disease activity and warrant further exploration of IIMs through experimental studies. This review introduces a dietary therapeutic approach using the Med Diet and related compounds to regulate chronic inflammatory processes in IIMs. However, further clinical studies are required to evaluate the efficacy of the Med Diet in patients with IIMs. Emphasising a clinical-nutritional approach, this study encourages future research on the anti-inflammatory effects of the Med Diet on IIMs. This review highlights potential insights for managing and treating these conditions using a holistic approach.

Vitamin D3 as an add-on treatment for multiple sclerosis: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Vitamin D deficiency has been linked to a higher risk of multiple sclerosis (MS) and disease progression. However, the efficacy of vitamin D3 as an adjuvant therapy for MS remains a controversial topic.

OBJECTIVE

To perform a systematic review and meta-analysis of randomized controlled trials to assess the impact of adjunct high-dose vitamin D3 on clinical and radiological outcomes.

METHODS

PubMed, Embase, and Cochrane Library were searched for trials published until December 18th, 2022. Authors independently selected randomized controlled trials involving patients with MS, with an intervention group receiving high dose (≥ 1000 IU/day) cholecalciferol and reporting clinical or radiological outcomes. Authors independently extracted data and assessed the risk of bias using a standardized, pilot-tested form. The meta-analysis was conducted using RStudio for EDSS at the last follow-up, ARR, and new T2 lesion count.

RESULTS

We included 9 studies with 867 participants. No significant reduction of EDSS (MD = 0.02, CI 95 % [-0.37; 0.41], p = 0.91), ARR (MD -0.03, CI 95 % [-0.08; 0.02], p = 0.26), or new T2 lesions (MD -0.59, CI 95 % [-1.24;0.07], p = 0.08) was observed at 6-24 months. We found no evidence of publication bias.

CONCLUSION

The findings of this meta-analysis strengthen current evidence that vitamin D3 supplementation has no significant impact on clinical outcomes in patients with MS. However, the non-significant reduction of new T2 lesions could precede long-term clinical benefits and should be validated in additional studies.

Vitamin D Supplementation: Effect on Cytokine Profile in Multiple Sclerosis

Vitamin D is known for its role in modulating calcium and phosphate homeostasis and is implicated both in bone mineralization and immune system regulation. The immune-modulatory role of vitamin D and its impact on multiple sclerosis (MS) courses are still debated. The aim of this review was to check the effect of vitamin D supplementation on cytokine profile regulation in people with MS. A significant increase in serum concentrations of interleukin (IL)-10 and Transforming growth factor (TGF)-β1 after vitamin D supplementation was demonstrated in most studies, with some of them reporting a reduction in disability scores after vitamin D supplementation and an inverse correlation between IL-10 levels and disability. The effect of vitamin D on the serum levels of IL-17 and IL-6 was controversial; different results across studies could be explained by a variability in the treatment duration, route, and frequency of administration, as well as the dosage of vitamin D supplementation, responses to vitamin D treatment and the serum levels reached with supplementation, including the methods used for cytokine analysis and the different cell types investigated, the MS phenotype, the disease phase (active vs. non-active) and duration, and concomitant treatment with disease-modifying therapies. Nevertheless, the significant increase in the serum concentrations of IL-10 and TGF-β1, demonstrated in most studies, suggests an anti-inflammatory effect of vitamin D supplementation.

Multiple Sclerosis-Associated Gut Microbiome in the Israeli Diverse Populations: Associations with Ethnicity, Gender, Disability Status, Vitamin D Levels, and Mediterranean Diet

Microbiome dysbiosis is increasingly being recognized as implicated in immune-mediated disorders including multiple sclerosis (MS). The microbiome is modulated by genetic and environmental factors including lifestyle, diet, and drug intake. This study aimed to characterize the MS-associated gut microbiome in the Israeli populations and to identify associations with demographic, dietary, and clinical features. The microbiota from 57 treatment-naive patients with MS (PwMS) and 43 age- and gender-matched healthy controls (HCs) was sequenced and abundance compared. Associations between differential microbes with demographic or clinical characteristics, as well as diet and nutrient intake, were assessed. While there was no difference in α- or β-diversity of the microbiome, we identified 40 microbes from different taxonomic levels that differ in abundance between PwMS and HCs, including Barnesiella, Collinsella, Egerthella, Mitsuokella, Olsenella Romboutsia, and Succinivibrio, all enhanced in PwMS, while several members of Lacnospira were reduced. Additional MS-differential microbes specific to ethnicity were identified. Several MS-specific microbial patterns were associated with gender, vitamin D level, Mediterranean diet, nutrient intake, or disability status. Thus, PwMS have altered microbiota composition, with distinctive patterns related to geographic locations and population. Microbiome dysbiosis seem to be implicated in disease progression, gender-related differences, and vitamin D-mediated immunological effects recognized in MS. Dietary interventions may be beneficial in restoring a "healthy microbiota" as part of applying comprehensive personalized therapeutic strategies for PwMS.

Pathogenesis and management of multiple sclerosis revisited

BACKGROUND

Multiple sclerosis is an autoimmune chronic inflammatory disease characterized by selective destruction of myelin in the CNS neurons (including optic nerve). It was first described in the 19th century and remained elusive owing to the disease's unique relapsing and remitting course. The widespread and debilitating prevalence of multiple sclerosis (MS) has prompted the development of various treatment modalities for its effective management.

METHODS AND OBJECTIVES

A literature review was conducted using the electronic databases PubMed and Google Scholar. The main objective of the review was to compile the advances in pathogenesis, classifications, and evolving treatment modalities for MS.

RESULTS

The understanding of the pathogenesis of MS and the potential drug targets for its precise treatment has evolved significantly over the past decade. The experimental developments are also motivating and present a big change coming up in the next 5 years. Numerous disease-modifying therapies (DMTs) have revolutionized the management of MS: interferon (IFN) preparations, monoclonal antibodies-natalizumab and ocrelizumab, immunomodulatory agents-glatiramer acetate, sphingosine 1-phosphate receptor 1 (S1PR1) modulators (Siponimod) and teriflunomide. The traditional parenteral drugs are now available as oral formulations improving patient acceptability. Repurposing various agents used for related diseases may reinforce the drug reserve to manage MS and are under trials. Although at a nascent phase, strategies to enhance re-myelination by stimulating oligodendrocytes are fascinating and hold promise for better outcomes in patients with MS.

CONCLUSIONS

The recent past has seen staggering inclusions to the management of multiple sclerosis catalyzing a significant turnabout in our approach to diagnosis, treatment, and prognosis. Since the advent of DMTs various other oral and injectable agents have been approved. The advances in MS therapeutics and diagnostics have laid the ground for further research and development to enhance the quality of life of afflicted patients.

The Role of Vitamin D in Neuroprotection in Multiple Sclerosis: An Update

Multiple sclerosis (MS) is a complex neurological condition that involves both inflammatory demyelinating and neurodegenerative components. MS research and treatments have traditionally focused on immunomodulation, with less investigation of neuroprotection, and this holds true for the role of vitamin D in MS. Researchers have already established that vitamin D plays an anti-inflammatory role in modulating the immune system in MS. More recently, researchers have begun investigating the potential neuroprotective role of vitamin D in MS. The active form of vitamin D, 1,25(OH)₂D₃, has a range of neuroprotective properties, which may be important in remyelination and/or the prevention of demyelination. The most notable finding relevant to MS is that 1,25(OH)₂D₃ promotes stem cell proliferation and drives the differentiation of neural stem cells into oligodendrocytes, which carry out remyelination. In addition, 1,25(OH)₂D₃ counteracts neurodegeneration and oxidative stress by suppressing the activation of reactive astrocytes and M1 microglia. 1,25(OH)₂D₃ also promotes the expression of various neuroprotective factors, including neurotrophins and antioxidant enzymes. 1,25(OH)₂D₃ decreases blood-brain barrier permeability, reducing leukocyte recruitment into the central nervous system. These neuroprotective effects, stimulated by 1,25(OH)₂D₃, all enhance neuronal survival. This review summarizes and connects the current evidence supporting the vitamin D-mediated mechanisms of action for neuroprotection in MS.

Effect of Vitamin D Supplementation on Fatigue in Multiple Sclerosis: A Systematic Review and Meta-Analysis

Vitamin D supplementation has been considered a possible treatment to reduce the risk of disease activity and progression in people with multiple sclerosis (MS). However, its effect on disease symptoms remains unclear. The aim of this meta-analysis was to conduct a systematic review to assess the effect of vitamin D on fatigue in this population. The systematic review was conducted using the MEDLINE, Cochrane Library, Embase and Web of Science databases from inception to May 2023. Randomized controlled trials (RCTs) reporting pre-post changes in fatigue after vitamin D supplementation were included. Pooled effect sizes and 95% confidence intervals (95% CIs) were calculated by applying a random effects model with Stata/SE (Version 16.0; StataCorp., College Station, TX, USA). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. A total of five studies with 345 individuals (271 females; age range: 25.4-41.1 years) were included. A significant reduction in fatigue was perceived when vitamin D supplementation was compared with a control group: -0.18 (95% CI: -0.36 to -0.01; I² = 0%). Thus, our findings show that the therapeutic use of vitamin D on fatigue in people with MS could be considered. Nevertheless, due to the lack of agreement on the dose to be applied, it is recommended to use it under medical prescription.

Molecular insights into the pathogenic impact of vitamin D deficiency in neurological disorders

Neurological disorders are the major cause of disability, leading to a decrease in quality of life by impairing cognitive, sensorimotor, and motor functioning. Several factors have been proposed in the pathogenesis of neurobehavioral changes, including nutritional, environmental, and genetic predisposition. Vitamin D (VD) is an environmental and nutritional factor that is widely distributed in the central nervous system's subcortical grey matter, neurons of the substantia nigra, hippocampus, thalamus, and hypothalamus. It is implicated in the regulation of several brain functions by preserving neuronal structures. It is a hormone rather than a nutritional vitamin that exerts a regulatory role in the pathophysiology of several neurological disorders, including Alzheimer's disease, Parkinson's disease, epilepsy, and multiple sclerosis. A growing body of epidemiological evidence suggests that VD is critical in neuronal development and shows neuroprotective effects by influencing the production and release of neurotrophins, antioxidants, immunomodulatory, regulation of intracellular calcium balance, and direct effect on the growth and differentiation of nerve cells. This review provides up-to-date and comprehensive information on vitamin D deficiency, risk factors, and clinical and preclinical evidence on its relationship with neurological disorders. Furthermore, this review provides mechanistic insight into the implications of vitamin D and its deficiency on the pathogenesis of neurological disorders. Thus, an understanding of the crucial role of vitamin D in the neurobiology of neurodegenerative disorders can assist in the better management of vitamin D-deficient individuals.

Clinical and Imaging Outcomes after Vitamin D Supplementation in Patients with Multiple Sclerosis: A Systematic Review

The link between vitamin D and multiple sclerosis (MS) has been suggested in epidemiological, genetic, immunological, and clinical studies. The aim of the present systematic review of the literature was to assess the effects of vitamin D supplementation on clinical and imaging outcomes in patients with MS. The outcomes we assessed included relapse events, disability progression, and magnetic resonance imaging (MRI) lesions. The search was conducted using PubMed, ClinicalTrials.gov, and EudraCT databases, and it included records published up until 28 February 2023. The systematic review was reported according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 guidelines. Nineteen independent clinical studies (corresponding to 24 records) were included in the systematic review. The risk of bias in randomized controlled trials (RCTs) was analyzed using the Cochrane risk-of-bias tool. Fifteen trials investigated relapse events, and most of them reported no significant effect of vitamin D supplementation. Eight of 13 RCTs found that vitamin D supplementation had no effect on disability [assessed by Expanded Disability Status Scale (EDSS) scores] compared to controls. Interestingly, recent RCTs reported a significant reduction in new MRI lesions in the central nervous system of MS patients during supplementation with vitamin D3.

Radiological Benefits of Vitamin D Status and Supplementation in Patients with MS—A Two-Year Prospective Observational Cohort Study

Current data emphasize the immunomodulating role of vitamin D in enhancing the anti-inflammatory response. Vitamin D deficiency is an established risk factor for developing multiple sclerosis—the autoimmune demyelinating and degenerative disease of the central nervous system. Several studies confirmed that higher vitamin D serum level is associated with better clinical and radiological outcomes in patients with multiple sclerosis, whereas vitamin D supplementation benefits in multiple sclerosis remain inconclusive. Despite that, many experts suggest regular measurements of vitamin D serum levels and supplementation in patients with multiple sclerosis. In this study, 133 patients with multiple sclerosis (relapsing–remitting subtype) were prospectively observed in a 0-, 12- and 24-month time span in a clinical setting. The study group consisted of 71.4% of patients (95 out of 133) supplementing vitamin D. The associations between vitamin D serum levels, clinical outcomes (disability status expressed by EDSS, number of relapses and time to relapse) and radiological outcomes (new T2-weighted lesions and number of gadolinium-enhanced lesions) were evaluated. There were no statistically significant correlations between clinical outcomes and vitamin D serum levels or supplementations. Fewer new T2-weighted lesions were observed in patients with vitamin D supplementations (p = 0.034) in 24 months of observation. Moreover, an optimal or higher level of vitamin D (>30 ng/mL) maintained throughout the entire observation period was associated with a lower number of new T2-weighted lesions in 24 months of observation (p = 0.045). These results support vitamin D implementation commencement and amelioration in patients with multiple sclerosis.

How Does Vitamin D Affect Immune Cells Crosstalk in Autoimmune Diseases?

Vitamin D is a secosteroid hormone that is highly involved in bone health. Mounting evidence revealed that, in addition to the regulation of mineral metabolism, vitamin D is implicated in cell proliferation and differentiation, vascular and muscular functions, and metabolic health. Since the discovery of vitamin D receptors in T cells, local production of active vitamin D was demonstrated in most immune cells, addressing the interest in the clinical implications of vitamin D status in immune surveillance against infections and autoimmune/inflammatory diseases. T cells, together with B cells, are seen as the main immune cells involved in autoimmune diseases; however, growing interest is currently focused on immune cells of the innate compartment, such as monocytes, macrophages, dendritic cells, and natural killer cells in the initiation phases of autoimmunity. Here we reviewed recent advances in the onset and regulation of Graves' and Hashimoto's thyroiditis, vitiligo, and multiple sclerosis in relation to the role of innate immune cells and their crosstalk with vitamin D and acquired immune cells.

Vitamin D and neurodegenerative diseases

Neurodegenerative diseases, featured by progressive loss of structure or function of neurons, are considered incurable at present. Movement disorders like tremor and postural instability, cognitive or behavioral disorders such as memory impairment are the most common symptoms of them and the growing patient population of neurodegenerative diseases poses a serious threat to public health and a burden on economic development. Hence, it is vital to prevent the occurrence of the diseases and delay their progress. Vitamin D can be transformed into a hormone in vivo with both genomic and non-genomic actions, exerting diverse physiological effects. Cumulative evidence indicates that vitamin D can ameliorate neurodegeneration by regulating pertinent molecules and signaling pathways including maintaining Ca²⁺ homeostasis, reducing oxidative stress, inhibiting inflammation, suppressing the formation and aggregation of the pathogenic protein, etc. This review updates discoveries of molecular mechanisms underlying biological functions of vitamin D in neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and vascular dementia. Clinical trials investigating the influence of vitamin D supplementation in patients with neurodegenerative diseases are also summarized. The synthesized information will probably provoke an enhanced understanding of the neuroprotective roles of vitamin D in the nervous system and provide therapeutic options for patients with neurodegenerative diseases in the future.

An Overview of the History, Pathophysiology, and Pharmacological Interventions of Multiple Sclerosis

Multiple sclerosis (MS) is an immune-inflammatory disease that attacks and damages myelinated axons in the central nervous system (CNS) and causes nontraumatic neurological impairment in young people. Historically, Lidwina of Schiedam documented the first MS case. After that, Augustus d'Este wrote for years about how his MS symptoms worsened. Age, sex, genetics, environment, smoking, injuries, and infections, including herpes simplex and rabies, are risk factors for MS. According to epidemiology, the average age of onset is between 20 and 40 years. MS is more prevalent in women and is common in Europe and America. As diagnostic methods and criteria change, people with MS may be discovered at earlier and earlier stages of the disease. MS therapy has advanced dramatically due to breakthroughs in our knowledge of the disease's etiology and progression. Therefore, the efficacy and risk of treatment medications increased exponentially. Management goals include reducing lesion activity and avoiding secondary progression. Current treatment approaches focus on managing acute episodes, relieving symptoms, and reducing biological activity. Disease-modifying drugs such as fingolimod, interferon-beta, natalizumab, and dimethyl fumarate are the most widely used treatments for MS. For proof of the efficacy and safety of these medications, investigations in the real world are necessary.

Vitamin D in Neurological Diseases

Vitamin D may have multiple effects on the nervous system and its deficiency can represent a possible risk factor for the development of many neurological diseases. Recent studies are also trying to clarify the different effects of vitamin D supplementation over the course of progressive neurological diseases. In this narrative review, we summarise vitamin D chemistry, metabolism, mechanisms of action, and the recommended daily intake. The role of vitamin D on gene transcription and the immune response is also reviewed. Finally, we discuss the scientific evidence that links low 25-hydroxyvitamin D concentrations to the onset and progression of severe neurological diseases, such as multiple sclerosis, Parkinson's disease, Alzheimer's disease, migraine, diabetic neuropathy and amyotrophic lateral sclerosis. Completed and ongoing clinical trials on vitamin D supplementation in neurological diseases are listed.

Peripheral T-Cells, B-Cells, and Monocytes from Multiple Sclerosis Patients Supplemented with High-Dose Vitamin D Show Distinct Changes in Gene Expression Profiles

Vitamin D is a steroid hormone that has been widely studied as a potential therapy for multiple sclerosis and other inflammatory disorders. Pre-clinical studies have implicated vitamin D in the transcription of thousands of genes, but its influence may vary by cell type. A handful of clinical studies have failed to identify an in vivo gene expression signature when using bulk analysis of all peripheral immune cells. We hypothesized that vitamin D's gene signature would vary by immune cell type, requiring the analysis of distinct cell types. Multiple sclerosis patients (n = 18) were given high-dose vitamin D (10,400 IU/day) for six months as part of a prospective clinical trial (NCT01024777). We collected peripheral blood mononuclear cells from participants at baseline and again after six months of treatment. We used flow cytometry to isolate three immune cell types (CD4⁺ T-cells, CD19⁺ B-cells, CD14⁺ monocytes) for RNA microarray analysis and compared the expression profiles between baseline and six months. We identified distinct sets of differentially expressed genes and enriched pathways between baseline and six months for each cell type. Vitamin D's in vivo gene expression profile in the immune system likely differs by cell type. Future clinical studies should consider techniques that allow for a similar cell-type resolution.

Full spectrum of vitamin D immunomodulation in multiple sclerosis: mechanisms and therapeutic implications

Vitamin D deficiency has been associated with the risk of multiple sclerosis, disease activity and progression. Results from in vitro experiments, animal models and analysis of human samples from randomized controlled trials provide comprehensive data illustrating the pleiotropic actions of Vitamin D on the immune system. They globally result in immunomodulation by decreasing differentiation of effector T and B cells while promoting regulatory subsets. Vitamin D also modulates innate immune cells such as macrophages, monocytes and dendritic cells, and acts at the level of the blood–brain barrier reducing immune cell trafficking. Vitamin D exerts additional activity within the central nervous system reducing microglial and astrocytic activation. The immunomodulatory role of Vitamin D detected in animal models of multiple sclerosis has suggested its potential therapeutic use for treating multiple sclerosis. In this review, we focus on recent published data describing the biological effects of Vitamin D in animal models of multiple sclerosis on immune cells, blood–brain barrier function, activation of glial cells and its potential neuroprotective effects. Based on the current knowledge, we also discuss optimization of therapeutic interventions with Vitamin D in patients with multiple sclerosis, as well as new technologies allowing in-depth analysis of immune cell regulations by vitamin D.

The Impact of Vitamin D Low Doses on Its Serum Level and Cytokine Profile in Multiple Sclerosis Patients

Vitamin D is known to have immunomodulatory properties and its deficiency is identified as an environmental risk factor for the development of autoimmune diseases, including multiple sclerosis. The aim of this study was to assess whether low-dose vitamin D supplementation could normalize the 25(OH)D serum levels in patients with relapsing-remitting multiple sclerosis (RRMS) and vitamin D deficiency (serum 25(OH)D < 75 nmol/L), and whether it may impact serum levels of selected cytokines. Among 44 patients (mean age 38.4 ± 10.1 years, 33 women and 11 men), after 12 months of low-dose vitamin D supplementation, serum levels of 25(OH)D normalized in 34 (77.3%) of the patients. Together with vitamin D increase, median levels of anti-inflammatory cytokines (IL10, TGF-β) and regulatory IFN-γ increased, while proinflammatory IL-17 remained unchanged. Moreover, an increase of inorganic phosphorus levels and decrease of PTH levels were observed, but without changes in total calcium concentration. These results may indicate that long-term supplementation with low doses of vitamin D is sufficient to compensate its deficiency in patients with RRMS and may help to maintain beneficial anti-inflammatory cytokine profile.

Vitamin D supplementation in multiple sclerosis: an expert opinion based on the review of current evidence

INTRODUCTION

Vitamin D has long been known for its immune-modulating effects, next to its function in calcium metabolism. As a consequence, poor vitamin D status has been associated with many diseases including multiple sclerosis (MS). Epidemiological studies suggest an association between a poor vitamin D status and development of MS and a poor vitamin D status is associated with more relapses and faster progression after patients are diagnosed with MS.

AREA’S COVERED

The aim of the authors was to review the role of vitamin D supplementation in the treatment of MS. Pubmed was used to review literature with a focus of vitamin D supplementation trials and meta-analyses in MS.

EXPERT OPINION

There is no solid evidence to support the application of vitamin D therapy, based on current available supplementation trials, although there are some promising results in the clinically isolated syndrome (CIS) patients and young MS patients early after initial diagnosis. The authors recommend further larger clinical trials with selected patient groups, preferable CIS patients and young patients at the time of diagnosis, using vitamin D₃ supplements to reach a 100 nmol/l level, to further investigate the effects of vitamin D supplementation in MS.

Effect of Vitamin D Supplements on Relapse Rate and Expanded Disability Status Scale (EDSS) in Multiple Sclerosis (MS): A Systematic Review and Meta-Analysis

Background

Multiple sclerosis (MS) is an inflammatory disease while there are controversies regarding the role of vitamin D supplements in controlling relapse and disability improvement during treatment.

Objective

The goal of this systematic review and meta-analysis was to evaluate the effect of vitamin D supplements on MS-related relapse and the Expanded Disability Status Scale (EDSS).

Methods

We searched databases to include randomized clinical trials (RCTs) which were published up to October 2018. We included RCTs, being single-blinded or double-blinded or open-label trials in which one of the main outcomes was EDSS and/or relapse after vitamin D supplementation. All statistical analyses were performed using RevMan 5.3. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for relapse between treatment arms. The mean difference was calculated for EDSS comparisons.

Results

Nine articles were included for analysis. Of these nine studies, five compared vitamin D supplement groups with placebo (group 1 studies), and four compared high- and low-dose vitamin D groups. A total of 561 patients were analyzed. Being treated with vitamin D instead of placebo showed no effect on relapse rate (OR = 0.66, 95% CI = 0.28-1.54) as well as EDSS (mean difference = 0.06, 95%CI [-0.31, 0.42]). The results of studies comparing high- vs. low-dose vitamin D interventions showed no significant effect on relapse rate (OR = 1.08, 95%CI [0.29-4.08] as well as final EDSS (mean difference = 0.17, 95% CI = -0.73, 1.07).

Conclusions

Our findings show that vitamin D supplements (high or low dose) have no significant effect on relapse rate and disability during treatment in MS patients.

Self-reported use of vitamin D supplements is associated with higher physical quality of life scores in multiple sclerosis

BACKGROUND

Sun exposure and vitamin D, including intake and serum levels, have been associated with reduced risk of MS onset and less progression and may affect quality of life (QoL). We investigated the prospective relationship of these factors with QoL from baseline to 2.5 years' follow-up, in an international cohort of people with MS.

METHODS

Data derive from the HOLISM international cohort. Sun exposure and vitamin D supplement use were queried at both timepoints. QoL was assessed by MSQOL-54, estimating physical and mental health QoL composite scores. Characteristics of QoL were assessed by linear regression, adjusted for age, sex, socioeconomic status, treated comorbidity number, MS type, disability, clinically significant fatigue, prescription antidepressant medication use, and ongoing relapse symptoms, and baseline QoL score, as appropriate, estimating adjusted coefficients (aβ).

RESULTS

At 2.5-year review, QoL scores were higher among those reporting taking vitamin D supplements (physical: aβ=3.58, 95%CI=1.35-5.80; mental: aβ=3.08, 95%CI=0.72-5.44), particularly average daily dose over 5,000IU/d. Baseline-reported vitamin D supplementation was associated with greater increase in physical (aβ=1.02, 95%CI=0.22-1.81), but not mental QoL (aβ=0.11, 95%CI=-1.00-1.23). Sun exposure was cross-sectionally associated with higher QoL scores at follow-up but was not associated with change in QoL.

CONCLUSIONS

Self-reported vitamin D supplement use was cross-sectionally associated with higher physical and mental QoL, but prospectively only with increased physical QoL.

The Effect of Different Administration Time and Dosage of Vitamin D Supplementation in Patients with Multiple Sclerosis: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Despite the vitamin D treatment in patients with multiple sclerosis (MS), there continues to be controversial discrepancy in outcomes according to the current research. Many systematic reviews have evaluated the effect of vitamin D as an adjuvant treatment in patients with MS; however, there is no consensus on the optimum administration time and dosage of vitamin D intake. A meta-analysis for exploring the different administration time and dosage of vitamin D is warranted.

METHODS

Randomized controlled trials (RCTs) on the effect of different administration time and dosage of vitamin D in patients with MS were recorded within 7 databases. This meta-analysis was performed with 2 clinical outcomes: EDSS (Expanded Disability Status Scale) and relapses during research.

RESULTS

The pooled results indicated that receiving different administration time and dosage of vitamin D as an adjuvant treatment had no significant therapeutic effect on MS according to the EDSS scores and relapses during research.

CONCLUSION

According to our meta-analysis, the administration of vitamin D in different dosages (ranging from 2,857 to 14,007 IU/day) and treatment period (ranging from 6 to 24 months) did not affect the clinical outcomes (EDSS and relapses during research) in patients with MS. Additional RCTs should be conducted to explore whether a longer duration and a larger dosage of vitamin D without serious adverse effects might produce therapeutic effects in patients with MS.

Implications of Vitamin D in Multiple Sclerosis and Other Neurodegenerative Processes: Bibliometric Analysis and Systematic Review

In recent years, numerous investigations focused on the pleiotropic actions of vitamin D have been carried out. These actions include the participation of this molecule in neurophysiological and neuropathological processes. As a consequence, abundant scientific literature on the role of this vitamin in neurodegenerative entities has emerged, even concerning clinical studies. To identify the level of scientific evidence concerning the relation between vitamin D and neurodegenerative diseases, from a quantitative and qualitative perspective. To describe, by means of a bibliometric analysis, the scientific production and its evolution through time in quantitative terms, regarding the implications of vitamin D in neurodegeneration. To analyse and present the degree of evidence in the aforementioned field of study, a systematic review of the literature focused on the most prevalent neurodegenerative diseases was carried out. We retrieved 848 articles in the bibliometric analysis, the majority of which were dated between the years 2010-2017. The most studied metabolite was the 25(OH)D3 and the most cited disease was multiple sclerosis. In the systematic review, we found studies about Alzheimer's and Parkinson's diseases and again, about multiple sclerosis prominently (in number and quality), with 12 randomised double-blind clinical trials. The research about vitamin D and its relations with neurodegenerative diseases shows a growing evolution over the last decade. More studies are needed to find correlations between the clinical severity of these diseases and the specific status of vitamin D and the genotypes related with them, which seems to be a future trend.

Immunoregulatory effects and therapeutic potential of vitamin D in multiple sclerosis

Initially recognised as an important factor for bone health, vitamin D is now known to have a range of effects on the immune system. Vitamin D deficiency is associated with an increased risk of multiple sclerosis (MS), a chronic immune-mediated demyelinating disease of the CNS. In this review, we explore the links between vitamin D deficiency, MS risk, and disease activity. We also discuss the known immune effects of vitamin D supplementation and the relevance of these observations to the immunopathology of MS. Finally, we review the existing evidence for vitamin D supplementation as an MS therapy, highlighting several recent clinical studies and trials.

The emerging role of lncRNAs in multiple sclerosis

Multiple sclerosis (MS) is the most common inflammatory demyelinating disease of the central nervous system (CNS) with various clinical manifestations. The characteristic of MS is that myelin is attacked by the body's immune system and increases the electrical capacity of axons, and is the primary pathophysiological mechanism of the transmission block. Studies have shown that epigenetic factors participate in the development of MS. LncRNAs are highly abundant and heterogeneous linear RNA transcripts with lengths exceeding 200 nucleotides and no protein-coding potential. Currently, pieces of evidence have demonstrated that lncRNAs have fundamental actions in multiple cellular pathways, including immune system regulation, epithelial-mesenchymal transition (EMT), cancer cell growth and metastasis, cellular homeostasis, and embryo development. It has been demonstrated that epigenetic mechanisms have an abundant role in the pathogenesis of MS in which the role of lncRNAs as epigenetic regulatory molecules in molecular processes has been proven. In this paper, we have focused on the correlation between MS and lncRNAs, the role of lncRNA in the pathogenesis of the disease, and the diagnostic and prognostic potential of lncRNA in MS.

Vitamin D as a Potential Therapy for Multiple Sclerosis: Where Are We?

Multiple sclerosis (MS) is a chronic demyelinating disease of the central nervous system and is caused by an aberrant immune response to myelin sheath. Disease-modifying medications, which mainly aim to suppress such aberrant immune response, have significantly improved MS treatment. However, the disease severity continues to worsen. In contrast, progressively more data suggest that 1,25-dihydroxyvitamin D or 1,25(OH)₂D, i.e., the active vitamin D, suppresses the differentiation of potentially pathogenic T cells associated with MS, enhances the differentiation of regulatory T cells that suppress the pathogenic T cells, and promotes remyelination. These novel 1,25(OH)₂D functions have encouraged investigators to develop vitamin D as a potential therapy for MS. However, because of the hypercalcemia that is associated with high 1,25(OH)₂D concentrations, supplementation of native vitamin D has been a major focus in clinical trials for the treatment of MS, but such trials have produced mixed data. In this article, we will review current progress in the supplementation of different vitamin D forms for the treatment of experimental autoimmune encephalomyelitis (i.e., an MS animal model) as well as MS. Furthermore, we will review alternative strategies that our laboratory and others are pursuing in an attempt to circumvent the hurdles that are hampering the effective use of vitamin D as a potential therapy for MS.

Vitamin D Supplementation in Multiple Sclerosis: A Critical Analysis of Potentials and Threats

Multiple sclerosis (MS) is a chronic inflammatory demyelinating and neurodegenerative disease of the central nervous system (CNS). In recent years, vitamin D has gained attention, as low serum levels are suspected to increase the risk for MS. Cholecalciferol supplementation has been tested in several clinical trials, since hypovitaminosis D was linked to higher disease activity and may even play a role in long-term outcome. Here, we review the current understanding of the molecular effects of vitamin D beyond calcium homeostasis, the potential beneficial action in MS and hazards including complications of chronic and high-dose therapy. In clinical trials, doses of up to 40,000 IU/day were tested and appeared safe as add-on therapy for short-term periods. A recent meta-analysis of a randomized, double-blind, placebo-controlled clinical trial investigating vitamin D as add-on therapy in MS, however, suggested that vitamin D had no therapeutic effect on disability or relapse rate. We recognize a knowledge gap for chronic and high-dose therapy, which can lead to life-threatening complications related to vitamin D toxicity including renal failure, cardiac arrythmia and status epilepticus. Moreover, vitamin D toxicity may manifest as fatigue, muscle weakness or urinary dysfunction, which may mimic the natural course of progressive MS. Given these limitations, vitamin D supplementation in MS is a sensitive task which needs to be supervised by physicians. While there is strong evidence for vitamin D deficiency and the development of MS, the risk-benefit profile of dosage and duration of add-on supplementation needs to be further clarified.

High-Dose Vitamin D-Mediated Hypercalcemia as a Potential Risk Factor in Central Nervous System Demyelinating Disease

The exact cause of multiple sclerosis (MS) is unknown; however, it is considered to be an inflammatory disease of the central nervous system (CNS) triggered by a combination of both environmental and genetic factors. Vitamin D deficiency is also discussed as a possible disease-promoting factor in MS, as low vitamin D status is associated with increased formation of CNS lesions, elevated number of relapses and accelerated disease progression. However, it remains unclear whether this association is causal and related and most importantly, whether vitamin D supplementation in MS is of direct therapeutic benefit. Recently, we could show that in a murine model of MS, administration of a moderate vitamin D dose was of clinical benefit, while excessive vitamin D supplementation had a negative effect on disease severity. Of note, disease exacerbation was associated with high-dose vitamin D caused secondary hypercalcemia. Mechanistically dissecting this outcome, we found that hypercalcemia independent of vitamin D similarly triggered activation of disease-perpetuating T cells. These findings caution that vitamin D should be supplemented in a controlled and moderate manner in patients with MS and concomitantly highlight calcium as a novel potential MS risk factor by itself. In this review, we will summarize the current evidence from animal and clinical studies aiming to assess whether vitamin D may be of benefit in patients with MS. Furthermore, we will discuss any possible secondary effects of vitamin D with a particular focus on the role of calcium on immune cells and in the pathogenesis of CNS demyelinating disease.

Vitamin D3 supplementation and neurofilament light chain in multiple sclerosis

OBJECTIVES

Low circulating vitamin D levels are associated with an increased risk of active MRI lesions and relapses in several cohorts with relapsing remitting multiple sclerosis (RRMS). Randomized controlled supplementation trials are, however, negative on their primary endpoints, while secondary MRI endpoints suggest anti-inflammatory effects. Circulating levels of neurofilament light chain (NfL) are a biomarker of disease activity in RRMS. We explored whether 48-week high-dose vitamin D₃ supplements were associated with lower circulating NfL levels.

MATERIALS & METHODS

Of N = 40 Dutch interferon beta-treated participants with RRMS of the SOLAR trial, plasma samples at baseline and 48-week follow-up were available. Of these participants, N = 24 were supplemented with 14 000 IU/d vitamin D₃ and N = 16 with placebo. Twenty-five hydroxyvitamin D₃ (25(OH)D₃ ) levels were measured with LC-MS/MS, and NfL levels were measured in duplicate with Simoa.

RESULTS

Serum 25(OH)D₃ levels at 48 weeks were increased in the vitamin D₃ when compared to placebo group (median level 281 [IQR 205-330] vs 72 [39-88] nmol/L; P < .01). NfL levels at 48 weeks did not differ between the treatment groups (median level 25.4 [IQR 19.6-32.2] vs 25.3 [17.9-30.1] pg/mL; P = .74). Higher week 48 NfL level showed a trend toward association with a higher risk of combined unique active lesions on the week 48 MRI scan (OR 2.39 [95% CI 0.93-6.12] for each 10 pg/mL increase; P = .07).

CONCLUSIONS

Supplementation of high-dose vitamin D₃ for 48 weeks was not associated with lower NfL levels. This study does not support an effect of vitamin D₃ on this biomarker of neuro-axonal injury.

An Update on Vitamin D and Disease Activity in Multiple Sclerosis

Vitamin D and its main active metabolite 1,25-dihydroxyvitamin D serve a crucial role in maintenance of a healthy calcium metabolism, yet have additional roles in immune and central nervous system cell homeostasis. Serum levels of 25-hydroxyvitamin D are a biomarker of future disease activity in patients with early relapsing-remitting multiple sclerosis (RRMS), and vitamin D supplementation in patients with low circulating 25-dihydroxyvitamin D levels has been anticipated as a potential efficacious treatment strategy. The results of the first large randomized clinical trials (RCTs), the SOLAR and CHOLINE studies, have now been published. The SOLAR study compared 14,000 IU of vitamin D3 (cholecalciferol) per day with placebo for 48 weeks in 232 randomized patients, whereas CHOLINE compared vitamin D3 100,000 IU every other week with placebo for 96 weeks in 129 randomized patients. All patients in both studies also used interferon-β-1a. None of the studies met their primary endpoints, which were no evidence of disease activity (NEDA-3) at 48 weeks in SOLAR and annualized relapse rate at 96 weeks in CHOLINE. Both studies did, however, suggest modest effects on secondary endpoints. Thus, vitamin D reduced the number of new or enlarging lesions and new T2 lesions in SOLAR, and the annualized relapse rate and number of new T1 lesions, volume of hypointense T1 lesions, and disability progression in the 90 patients who completed 96 weeks' follow-up in CHOLINE. We conclude that none of the RCTs on vitamin supplementation in MS have met their primary clinical endpoint in the intention to treat cohorts. This contrasts the observation studies, where each 25 nmol/l increase in 25-hydroxyvitamin D levels were associated with 14-34% reduced relapse risk and 15-50% reduced risk of new lesions on magnetic resonnance imaging. This discrepancy may have several explanations, including confounding and reverse causality in the observational studies. The power calculations of the RCTs have been based on the observational studies, and the RCTs may have been underpowered to detect less prominent yet important effects of vitamin D supplementation. Although the effect of vitamin D supplementation is uncertain and less pronounced than suggested by observational studies, current evidence still support that people with MS should avoid vitamin D insufficiency, and preferentially aim for vitamin D levels around 100 nmol/L or somewhat higher.

Vitamin D deficiency and its association with fatigue and quality of life in multiple sclerosis patients

Background

Vitamin D deficiency is associated with the incidence and prevalence of a variety of neurologic disorders, including multiple sclerosis. However, available studies to date have not provided convincing evidence that vitamin D treatment improves fatigue and life quality in patients with multiple sclerosis.

Aim

To assess the relationship of vitamin D deficiency with health-related quality-of-life issues and fatigue in multiple sclerosis patients.

Methods

Vitamin D3 levels were measured in 149 multiple sclerosis patients. In patients with lower than 30 ng/mL levels, vitamin D was administered. Fatigue and health-related quality of life scores were measured at baseline and months 1, 3, 6, and 12 after the beginning of vitamin D3 administration.

Results

Among 149 patients, 90% were vitamin D deficient. After vitamin D supplementation, health-related quality of life and fatigue scores improved significantly. There was a direct association between health-related quality of life with absence of fatigue and vitamin D status at the end of study.

Conclusion

The 90% frequency of multiple sclerosis patients with vitamin D deficiency, together with the significant association of vitamin D status with the absence of fatigue and improved physical and functional well-being, points to vitamin D supplementation as a potential therapy to enhance the patient's quality of life.

Relevance of the article for predictive preventive and personalized medicine

This article emphasizes that vitamin D supplementation can improve clinical outcome in multiple sclerosis patients providing immune modulation and neuroprotection. Identification and correction of vitamin D deficiency has the potential to treat the related quality of life in patients with multiple sclerosis.

The effects of vitamin D supplementation on expanded disability status scale in people with multiple sclerosis: A critical, systematic review and metaanalysis of randomized controlled trials

In this meta-analysis of randomized controlled trials (RCTs), the effects of vitamin D supplementation on the scores for the expanded disability status scale (EDSS) in people with multiple sclerosis (MS) are assessed. The following databases were search up to January 2018: MEDLINE, EMBASE, Web of Science, and Cochrane Central Register of Controlled Trials. The quality of the relevant extracted data was assessed according to the Cochrane risk of bias tool. Data were pooled by the use of the inverse variance method and expressed as mean difference with 95% Confidence Intervals (95% CI). Six studies were included in this meta-analysis. The findings demonstrated that supplementation with vitamin D alone and vitamin D plus calcium did not affect the EDSS score (WMD -0.11 (-0.33, 0.11); P = 0.32). In addition, subgroup analysis showed that vitamin D supplementation alone, when compared to the use of a placebo, and vitamin D plus calcium supplementation compared with the control did not affect EDSS (WMD -0.13 (-0.30, 0.11); P = 0.29) and (WMD -0.08 (-0.57, 0.41); P = 0.29), respectively. Overall, this meta-analysis indicated that taking vitamin D in people with MS had no significant effect on EDSS.

The Gut Microbiota in Multiple Sclerosis: An Overview of Clinical Trials

Multiple sclerosis (MS) is a chronic, inflammatory, demyelinating, and degenerative disease that affects the central nervous system. A recent study showed that interaction between the immune system and the gut microbiota plays a crucial role in the development of MS. This review reports the clinical studies carried out in recent years that aimed to evaluate the composition of the microbiota in patients with relapsing–remitting MS (RR-MS). We also report what is available in the literature regarding the effectiveness of fecal microbiota transplantation and the role of the diet in restoring the intestinal bacterial population. Studies report that patients with RR-MS have a microbiota that, compared with healthy controls, has higher amounts of Pedobacteria, Flavobacterium, Pseudomonas, Mycoplana, Acinetobacter, Eggerthella, Dorea, Blautia, Streptococcus and Akkermansia. In contrast, MS patients have a microbiota with impoverished microbial populations of Prevotella, Bacteroides, Parabacteroides, Haemophilus, Sutterella, Adlercreutzia, Coprobacillus, Lactobacillus, Clostridium, Anaerostipes and Faecalibacterium. In conclusion, the restoration of the microbial population in patients with RR-MS appears to reduce inflammatory events and the reactivation of the immune system.

Dietary Supplements on Controlling Multiple Sclerosis Symptoms and Relapses: Current Clinical Evidence and Future Perspectives

Background: Multiple sclerosis (MS) constitutes a chronic progressive demyelinating disease which negatively affects the central nervous system. MS symptoms detrimentally affect the quality of life, as well as the life expectancy of MS patients. In this aspect, the present study aims to critically summarize and evaluate the currently available clinical studies focusing on the potential beneficial effects of dietary supplements on controlling MS symptomatology and relapse. Methods: PubMed database was comprehensively searched, using relative keywords to identify clinical trials that investigated the beneficial effects of dietary supplementation against MS symptomatology and progression. 40 clinical trials were found, which were divided into categories. Results: Nutritional status of MS patients, as well as supplementation have been suggested as potential factors affecting progression. Several substantial studies have documented a systematically high prevalence of vitamin A, B12 and D3 deficiency amongst MS patients. At present, clinical data have suggested that most of the dietary supplements under study may exert antioxidant and anti-inflammatory properties, improving depression symptomatology and quality of life overall. However, malnutrition risk in MS patients has not been adequately explored in order for more precise conclusions to be drawn. The supplements that may have a positive effect on MS are vitamins, fatty acids, antioxidants, phytochemicals and melatonin. Conclusions: Several dietary supplements may decrease inflammation and fatigue, also increasing also autoimmunity tolerance in MS patients, and thus improving quality of life and life expectancy. Currently, there is no effective clinical indication for applying dietary supplementation as complementary treatment against MS symptomatology.

Effectiveness of Vitamin D Supplementation in the Management of Multiple Sclerosis: A Systematic Review

Objective: to examine the extent of effect vitamin D in Multiple Sclerosis (MS) on pathology and symptoms. Methods: A literature search was performed in November 2018 (CRD42018103615). Eligibility criteria: randomised control trials in English from 2012 to 2018; a clinical diagnosis of MS; interventions containing vitamin D supplementation (vitamin D3 or calcitriol) in disease activity compared to a control/placebo; improvement in: serum 25(OH)D, relapse rates, disability status by Expanded Disability Status Scale (EDSS) scores, cytokine profile, quality of life, mobility, T2 lesion load and new T2 or T1 Gd enhancing lesions, safety and adverse effects. Risk of bias was evaluated. Results: Ten studies were selected. The study size ranged from 40 to 94 people. All studies evaluated the use of vitamin D supplementation (ranging from 10 to 98,000 IU), comparing to a placebo or low dose vitamin D. The duration of the intervention ranged from 12 to 96 weeks. One trial found a significant effect on EDSS score, three demonstrated a significant change in serum cytokines level, one found benefits to current enhancing lesions and three studies evaluating the safety and tolerability of vitamin D reported no serious adverse events. Disease measures improved to a greater extent overall in those with lower baseline serum 25(OH)D levels. Conclusions: As shown in 3 out of 10 studies, improvement in disease measures may be more apparent in those with lower baseline vitamin D levels.

The Role of Vitamin D in the Pathogenesis of Adolescent Idiopathic Scoliosis

Several theories have been proposed to explain the etiology of adolescent idiopathic scoliosis (AIS) until present. However, limited data are available regarding the impact of vitamin D insufficiency or deficiency on scoliosis. Previous studies have shown that vitamin D deficiency and insufficiency are prevalent in adolescents, including AIS patients. A series of studies conducted in Hong Kong have shown that as many as 30% of these patients have osteopenia. The 25-hydroxyvitamin D3 level has been found to positively correlate with bone mineral density (BMD) in healthy adolescents and negatively with Cobb angle in AIS patients; therefore, vitamin D deficiency is believed to play a role in AIS pathogenesis. This study attempts to review the relevant literature on AIS etiology to examine the association of vitamin D and various current theories. Our review suggested that vitamin D deficiency is associated with several current etiological theories of AIS. We postulate that vitamin D deficiency and/or insufficiency affects AIS development by its effect on the regulation of fibrosis, postural control, and BMD. Subclinical deficiency of vitamin K2, a fat-soluble vitamin, is also prevalent in adolescents; therefore, it is possible that the high prevalence of vitamin D deficiency is related to decreased fat intake. Further studies are required to elucidate the possible role of vitamin D in the pathogenesis and clinical management of AIS.

Vitamin D for the treatment of multiple sclerosis: a meta-analysis

OBJECTIVE

There is an association between latitude, relative vitamin D deficiency and risk of multiple sclerosis (MS), and an association between vitamin D and disease progression. We have performed a meta-analysis with the aim of investigating the role of therapeutic vitamin D in MS.

METHODS

A systematic search of databases was performed to identify clinical trials assessing vitamin D in patients with relapsing-remitting MS. Studies were selected based on inclusion and exclusion criteria. Analysis was performed using RevMan 5.3 software.

RESULTS

Twelve studies involving 950 patients were included in the final analysis. Studies were divided into four groups because of heterogeneity in study design. Studies were judged to be at low or unclear risk of bias, except in three studies, and this was confirmed by funnel plots. No statistically significant difference was seen for any of the outcome measures. There were non-significant trends in favour of vitamin D for all outcome measures, particularly when only placebo-controlled studies were included. Dose comparison studies showed a significant increase in annualised relapse rate (mean difference 0.15 [95%CI 0.01-0.30]) and non-significant trends of increased Expanded Disability Status Scale and gadolinium-enhancing lesions for the higher-dose arms.

CONCLUSION

These findings suggest that vitamin D supplementation may have a therapeutic role in the treatment of MS. However, there is uncertainty with regard to the most appropriate dose, with high doses potentially being associated with worse outcomes. There remains the need for further well-performed randomised, dose-ranging, placebo-controlled trials of vitamin D in MS.

Vitamin D for the management of multiple sclerosis

BACKGROUND

This review is an update of a previously published review, "Vitamin D for the management of multiple sclerosis" (published in the Cochrane Library; 2010, Issue 12). Multiple sclerosis (MS) is characterised by inflammation, demyelination, axonal or neuronal loss, and astrocytic gliosis in the central nervous system (CNS), which can result in varying levels of disability. Some studies have provided evidence showing an association of MS with low levels of vitamin D and benefit derived from its supplementation.

OBJECTIVES

To evaluate the benefit and safety of vitamin D supplementation for reducing disease activity in people with MS.

SEARCH METHODS

We searched the Cochrane Multiple Sclerosis and Rare Diseases of the CNS Specialized Register up to 2 October 2017 through contact with the Information Specialist with search terms relevant to this review. We included references identified from comprehensive electronic database searches and from handsearches of relevant journals and abstract books from conferences.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs that compared vitamin D versus placebo, routine care, or low doses of vitamin D in patients with MS. Vitamin D was administered as monotherapy or in combination with calcium. Concomitant interventions were allowed if they were used equally in all trial intervention groups.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and assessed the methodological quality of studies, while another review author sorted any disagreements. We expressed treatment effects as mean differences (MDs) for continuous outcomes (Expanded Disability Status Scale and number of magnetic resonance imaging (MRI) gadolinium-enhancing T1 lesions), as standardised MDs for health-related quality of life, as rate differences for annualised relapse rates, and as risk differences (RDs) for serious adverse events and minor adverse events, together with 95% confidence intervals (CIs).

MAIN RESULTS

We identified 12 RCTs enrolling 933 participants with MS; 464 were randomised to the vitamin D group, and 469 to the comparator group. Eleven trials tested vitamin D₃, and one trial tested vitamin D₂. Vitamin D₃ had no effect on the annualised relapse rate at 52 weeks' follow-up (rate difference -0.05, 95% CI -0.17 to 0.07; I² = 38%; five trials; 417 participants; very low-quality evidence according to the GRADE instrument); on the Expanded Disability Status Scale at 52 weeks' follow-up (MD -0.25, 95% CI -0.61 to 0.10; I² = 35%; five trials; 221 participants; very low-quality evidence according to GRADE); and on MRI gadolinium-enhancing T1 lesions at 52 weeks' follow-up (MD 0.02, 95% CI -0.45 to 0.48; I² = 12%; two trials; 256 participants; very low-quality evidence according to GRADE). Vitamin D₃ did not increase the risk of serious adverse effects within a range of 26 to 52 weeks' follow-up (RD 0.01, 95% CI -0.03 to 0.04; I² = 35%; eight trials; 621 participants; low-quality evidence according to GRADE) or minor adverse effects within a range of 26 to 96 weeks' follow-up (RD 0.02, 95% CI -0.02 to 0.06; I² = 20%; eight trials; 701 participants; low-quality evidence according to GRADE). Three studies reported health-related quality of life (HRQOL) using different HRQOL scales. One study reported that vitamin D improved ratings on the psychological and social components of the HRQOL scale but had no effects on the physical components. The other two studies found no effect of vitamin D on HRQOL. Two studies reported fatigue using different scales. One study (158 participants) reported that vitamin D₃ reduced fatigue compared with placebo at 26 weeks' follow-up. The other study (71 participants) found no effect on fatigue at 96 weeks' follow-up. Seven studies reported on cytokine levels, four on T-lymphocyte proliferation, and one on matrix metalloproteinase levels, with no consistent pattern of change in these immunological outcomes. The randomised trials included in this review provided no data on time to first treated relapse, number of participants requiring hospitalisation owing to progression of the disease, proportion of participants who remained relapse-free, cognitive function, or psychological symptoms.

AUTHORS' CONCLUSIONS

To date, very low-quality evidence suggests no benefit of vitamin D for patient-important outcomes among people with MS. Vitamin D appears to have no effect on recurrence of relapse, worsening of disability measured by the Expanded Disability Status Scale (EDSS), and MRI lesions. Effects on health-related quality of life and fatigue are unclear. Vitamin D₃ at the doses and treatment durations used in the included trials appears to be safe, although available data are limited. Seven ongoing studies will likely provide further evidence that can be included in a future update of this review.

Modulatory Effects of Dietary Amino Acids on Neurodegenerative Diseases

Proteins are playing a vital role in maintaining the cellular integrity and function, as well as for brain cells. Protein intake and supplementation of individual amino acids can affect the brain functioning and mental health, and many of the neurotransmitters in the brain are made from amino acids. The amino acid supplementation has been found to reduce symptoms, as they are converted into neurotransmitters which in turn extenuate the mental disorders. The biosynthesis of amino acids in the brain is regulated by the concentration of amino acids in plasma. The brain diseases such as depression, bipolar disorder, schizophrenia, obsessive-compulsive disorder (OCD), and Alzheimer's (AD), Parkinson's (PD), and Huntington's diseases (HD) are the most common mental disorders that are currently widespread in numerous countries. The intricate biochemical and molecular machinery contributing to the neurological disorders is still unknown, and in this chapter, we revealed the involvement of dietary amino acids on neurological diseases.

Are the protective benefits of vitamin D in neurodegenerative disease dependent on route of administration? A systematic review

Background: The clinical and preclinical exploration of the therapeutic properties of vitamin D have significantly increased in the past decade, owing to the growing associative evidence suggesting vitamin D is neuroprotective. However, whether depletion of vitamin D contributes to the onset of neurological disorders or is a symptom of neurological disease has yet to be defined. Much remains unclear about the causal role of vitamin D and the method of use and forms of vitamin D.Objectives: We sought to quantitatively assess if neuroprotective benefits from vitamin D in neurodegenerative diseases are dependent on route of administration: comparing the effect of endogenously sourced vitamin D from UV exposure to exogenously derived vitamin D through synthetic supplementation.Design: We systematically searched PubMed, Embase and PsycInfo databases which included both pre-clinical and clinical studies investigating vitamin D in neurodegenerative diseases. Articles were subject to strict inclusion criteria and objectively assessed for quality. Additionally, Medline data was analysed to identify trends in topic publications and linguistic characteristics of papers.Results: From a total of 231 screened articles, we identified 73 appropriate for review based on inclusion criteria: original studies that investigated vitamin D levels or levels of vitamin D supplementation in neurodegenerative diseases or investigated past/present sun exposure in disease cohorts. Results indicate there is insufficient evidence to comprehensively reflect on a potential neuroprotective role for vitamin D and if this was dependent on route of administration. The majority of current data supporting neuroprotective benefits from vitamin D are based on pre-clinical and observational studies. Solid evidence is lacking to support the current hypothesis that the beneficial effect of UV exposure results from the synthesis of vitamin D. Sun exposure, independent of vitamin D production, may be protective against multiple Sclerosis, Parkinson's disease and Alzheimer's disease. Yet, further research is required to elucidate the beneficial mechanism of actions of UV exposure. The literature of vitamin D and amyotrophic lateral sclerosis was limited, and no conclusions were drawn. Therefore, in cases where UV-derived vitamin D was hypothesized to be the beneficial mediator in the neuroprotective effects of sun exposure, we propose results are based only on associative evidence.Conclusion: On the basis of this systematic review, strong recommendations regarding therapeutic benefits of vitamin D in neurodegenerative disease cannot be made. It is unclear if vitamin D mediates a protective benefit in neurodegenerative disease or whether it is an associative marker of UV exposure, which may contribute to as of yet unidentified neuroprotective factors.

The efficacy of vitamin D in multiple sclerosis: A meta-analysis

BACKGROUND

Multiple sclerosis (MS) is a chronic inflammatory demyelination disorder in the central nervous system (CNS) leading to a high level of neurological disability. The pathogenesis of MS remains largely unknown, which explains the lack of significant efficacy of therapy in MS. Vitamin D deficiency is widely considered to be an environmental risk factor for MS. Many studies investigating the therapeutic effects of vitamin D on MS have been applied. The objective of this systematic review and meta-analysis was to evaluate the effectiveness of vitamin D in MS patients.

METHODS

To obtain a more comprehensive estimate of the efficacy of vitamin D on MS patients, we conducted a meta-analysis to determine the role of vitamin D in MS. The PubMed, EMBASE and Cochrane databases were searched in October 2017. Randomized, double-blind, placebo-controlled clinical trials recorded within the three main databases were considered. The analysis was conducted for two specific outcomes: Expanded Disability Status Scale (EDSS) score and annual relapse rate (ARR).

RESULTS

Vitamin D₃ as add-on treatment had no significant therapeutic effect on MS according to EDSS score (mean difference -0.01 [95% CI -0.34 to 0.33]). The ARR was higher in the vitamin D group than in the placebo group (mean difference 0.05 [95% CI 0.01 to 0.1]).

CONCLUSION

Our findings suggest that vitamin D appeared to have no therapeutic effect on EDSS score or ARR in the patients with MS.

Genomic Effects of the Vitamin D Receptor: Potentially the Link between Vitamin D, Immune Cells, and Multiple Sclerosis

Vitamin D has a plethora of functions that are important for the maintenance of general health and in particular, the functional integrity of the immune system, such as promoting an anti-inflammatory cytokine profile and reducing the Treg/Th17 ratio. Multiple sclerosis (MS) is a chronic, inflammatory, and neurodegenerative central nervous system (CNS) disorder of probable autoimmune origin. MS is characterized by recurring or progressive demyelination and degeneration of the CNS due in part to a misguided immune response to as yet undefined (CNS) antigens, potentially including myelin basic protein and proteolipid protein. MS has also been shown to be associated significantly with environmental factors such as the lack of vitamin D. The role of vitamin D in the pathogenesis and progression of MS is complex. Recent genetic studies have shown that various common MS-associated risk-single-nucleotide polymorphisms (SNPs) are located within or in the vicinity of genes associated with the complex metabolism of vitamin D. The functional aspects of these genetic associations may be explained either by a direct SNP-associated loss- or gain-of-function in a vitamin D-associated gene or due to a change in the regulation of gene expression in certain immune cell types. The development of new genetic tools using next-generation sequencing: e.g., chromatin immunoprecipitation sequencing (ChIP-seq) and the accompanying rapid progress of epigenomics has made it possible to recognize that the association between vitamin D and MS could be based on the extensive and characteristic genomic binding of the vitamin D receptor (VDR). Therefore, it is important to analyze comprehensively the spatiotemporal VDR binding patterns that have been identified using ChIP-seq in multiple immune cell types to reveal an integral profile of genomic VDR interaction. In summary, the aim of this review is to connect genomic effects vitamin D has on immune cells with MS and thus, to contribute to a better understanding of the influence of vitamin D on the etiology and the pathogenesis of this complex autoimmune disease.

Zika Virus as an Emerging Neuropathogen: Mechanisms of Neurovirulence and Neuro-Immune Interactions

Zika virus (ZIKV) is an emerging arbovirus of the genus Flaviviridae, which causes a febrile illness and has spread from across the Pacific to the Americas in a short timeframe. Convincing evidence has implicated the ZIKV to incident cases of neonatal microcephaly and a set of neurodevelopmental abnormalities referred to as the congenital Zika virus syndrome. In addition, emerging data points to an association with the ZIKV and the development of the so-called Guillain-Barre syndrome, an acute autoimmune polyneuropathy. Accumulating knowledge suggests that neurovirulent strains of the ZIKV have evolved from less pathogenic lineages of the virus. Nevertheless, mechanisms of neurovirulence and host-pathogen neuro-immune interactions remain incompletely elucidated. This review provides a critical discussion of genetic and structural alterations in the ZIKV which could have contributed to the emergence of neurovirulent strains. In addition, a mechanistic framework of neuro-immune mechanisms related to the emergence of neuropathology after ZIKV infection is discussed. Recent advances in knowledge point to avenues for the development of a putative vaccine as well as novel therapeutic strategies. Nevertheless, there are unique unmet challenges that need to be addressed in this regard. Finally, a research agenda is proposed.

Narrowband UVB Phototherapy for Clinically Isolated Syndrome: A Trial to Deliver the Benefits of Vitamin D and Other UVB-Induced Molecules

Low vitamin D and insufficient sun exposure are additive independent risk factors for the development of multiple sclerosis (MS). The usual measure of vitamin D status, serum 25-hydroxy vitamin D [25(OH)D], is also a marker of recent exposure to the UVB rays of sunshine. The main evidence for a protective effect for MS development of higher 25(OH)D comes from observational studies, but this study design cannot separate out whether 25(OH)D is acting as a marker of vitamin D status, sun exposure, or both. In light of a lack of definitive outcomes in MS patients after trials of vitamin D supplementation and the ability of narrowband UVB to induce vitamin D, as well as other immune-regulatory molecules in skin, the Phototherapy for Clinically Isolated Syndrome (PhoCIS) trial was established to investigate the benefits of narrowband UVB, in addition to supplemented vitamin D, on MS development in individuals with Clinically Isolated Syndrome. We propose that the PhoCIS trial provides a fresh approach to re-defining the reported associations of 25(OH)D levels with MS development and progression.

Metabolomics: A potential way to know the role of vitamin D on multiple sclerosis

The literature about the influence of vitamin D on multiple sclerosis (MS) is very controversial, possibly as a result of the way through which the research on the subject has been conducted. The studies developed so far have been focused exclusively on gene expression: the effect of a given vitamin D metabolite on target receptors. The influence of the vitamin D status (either natural or after supplementation) on MS has been studied by measurement of the 25 monohydroxylated metabolite (also known as circulating form), despite the 1,25 dihydroxylated metabolite is considered the active form. In the light of the multiple metabolic pathways in which both forms of vitamin D (D₂ and D₃) are involved, monitoring of the metabolites is crucial to know the activity of the target enzymes as a function of both the state of the MS patient and the clinical treatment applied. The study of metabolomics aspects is here proposed to clarify the present controversy. In "omics" terms, our proposal is to take profit from up-stream information-thus is, from metabolomics to genomics-with a potential subsequent step to systems biology, if required.

Dietary Interventions in Multiple Sclerosis: Development and Pilot-Testing of an Evidence Based Patient Education Program

Background

Dietary factors have been discussed to influence risk or disease course of multiple sclerosis (MS). Specific diets are widely used among patients with MS.

Objective

To design and pilot-test an evidence based patient education program on dietary factors in MS.

Methods

We performed a systematic literature search on the effectiveness of dietary interventions in MS. A web-based survey among 337 patients with MS and 136 healthy controls assessed knowledge, dietary habits and information needs. An interactive group education program was developed and pilot-tested.

Results

Fifteen randomised-controlled trials (RCTs) were included in the systematic review. Quality of evidence was low and no clear benefit could be seen. Patients with MS significantly more often adhered to a `Mediterranean Diet`(29.7% versus 14.0%, p<0.001) compared to controls. 143 (42%) of the patients with MS had tried special MS diets. Important information needs addressed effectiveness of MS diets (44%) and relation between nutrition and MS (43%). A pilot test of our newly developed patient education program with 13 participants showed excellent comprehensibility and the MS-specific content was judged as very important. However, the poor evidence base for dietary approaches in MS was perceived disappointing.

Conclusions

Development and pilot-testing of an evidence-based patient education program on nutrition and MS is feasible. Patient satisfaction with the program suffers from the lack of evidence. Further research should focus on generating evidence for the potential influence of lifestyle habits (diet, physical activity) on MS disease course thus meeting the needs of patients with MS.

Immune regulatory effects of high dose vitamin D3 supplementation in a randomized controlled trial in relapsing remitting multiple sclerosis patients receiving IFNβ; the SOLARIUM study

Multiple sclerosis (MS) is characterized by a disturbed immune homeostasis and low serum vitamin D levels are associated with an increased disease activity. While vitamin D has been hypothesized to promote the maintenance of immune homeostasis, vitamin D supplementation could be of benefit to patients with MS. The SOLAR study investigated the effects of high dose vitamin D₃ supplementation on clinical outcomes in a randomized controlled trial. Here we present the immune regulatory effects, investigated in the SOLARIUM sub-study. Thirty Dutch relapsing remitting (RR) MS patients treated with IFNβ-1a received high dose vitamin D₃ supplementation and 23 patients received placebo during a period of 48weeks. Lymphocytes were phenotypically characterized by flow cytometry and in vitro cytokine secretion was assessed in the presence or absence of 1,25(OH)₂D₃ using Luminex technology. Changes in immune regulatory parameters were determined within subjects as well as between treatment groups. The proportion of cells in the immune regulatory cell compartment (nTreg, iTreg and Breg) was not altered upon high dose vitamin D₃ supplementation. Proportions of T helper subsets were not affected by vitamin D₃, except for the proportion of IL4⁺ Th cells, which decreased in the placebo but not in the vitamin D₃ group. T cell cytokine secretion increased, most pronounced for IL5 and latency activated protein of TGFβ, in the placebo group but not in the vitamin D₃ group. Lymphocytes remained equally reactive to in vitro 1,25(OH)₂D₃. In conclusion, high dose vitamin D₃ supplementation did not result in a relative increase in lymphocytes with a regulatory phenotype. However, this study supports the hypothesis that vitamin D contributes to the maintenance of immune homeostasis by preventing further disturbance of the T cell compartment early in the disease course of MS.