Evaluating the Clinical Utility of Epstein-Barr Virus Antibodies as Biomarkers in Multiple Sclerosis: A Systematic Review

BACKGROUND

EBV is a necessary but not sufficient factor in the pathophysiology of multiple sclerosis (MS). EBV antibodies to the nuclear antigen (EBNA1) and viral capsid antigen (VCA) rise rapidly prior to MS disease manifestations, and their absence has clinical utility with a high negative predictive value. It remains unclear whether EBV levels act as prognostic, monitoring, or pharmacodynamic/response biomarkers. Substantial literature on this topic exists but has not been systematically reviewed. We hypothesized that EBV levels against EBNA1 and VCA are potential prognostic and monitoring biomarkers in MS, and that patient population, MS clinical phenotype, and EBV assay method may play important roles in explaining variation among study outcomes.

METHODS

We systematically searched PubMed and EMBASE from inception to April 1, 2022. After removal of duplicates, records were screened by abstract. Remaining full-text articles were reviewed. Clinical and MRI data were extracted from full-text articles for comparison and synthesis.

RESULTS

Searches yielded 696 unique results; 285 were reviewed in full, and 36 met criteria for data extraction. Heterogeneity in sample population, clinical outcome measures, assay methods and statistical analyses precluded a meta-analysis. EBV levels were not consistently associated with clinical disease markers including conversion from CIS to RRMS, neurological disability, or disease phenotype. Studies using repeated-measures design suggest that EBNA1 levels may temporarily reflect inflammatory disease activity as assessed by gadolinium-enhancing Magnetic Resonance Imaging (MRI) lesions. Limited data also suggest a decrease in EBV levels following initiation of certain disease-modifying therapies.

CONCLUSION

Heterogeneous methodology limited generalization and meta-analysis. EBV antibody levels are unlikely to represent prognostic biomarkers in MS. The areas of highest ongoing promise relate to diagnostic exclusion and pharmacodynamic/disease response. Use of EBV antibodies as biomarkers in clinical practice remains additionally limited by lack of methodological precision, reliability, and validation.

Precision nutrition to reset virus-induced human metabolic reprogramming and dysregulation (HMRD) in long-COVID

SARS-CoV-2, the etiological agent of COVID-19, is devoid of any metabolic capacity; therefore, it is critical for the viral pathogen to hijack host cellular metabolic machinery for its replication and propagation. This single-stranded RNA virus with a 29.9 kb genome encodes 14 open reading frames (ORFs) and initiates a plethora of virus-host protein-protein interactions in the human body. These extensive viral protein interactions with host-specific cellular targets could trigger severe human metabolic reprogramming/dysregulation (HMRD), a rewiring of sugar-, amino acid-, lipid-, and nucleotide-metabolism(s), as well as altered or impaired bioenergetics, immune dysfunction, and redox imbalance in the body. In the infectious process, the viral pathogen hijacks two major human receptors, angiotensin-converting enzyme (ACE)-2 and/or neuropilin (NRP)-1, for initial adhesion to cell surface; then utilizes two major host proteases, TMPRSS2 and/or furin, to gain cellular entry; and finally employs an endosomal enzyme, cathepsin L (CTSL) for fusogenic release of its viral genome. The virus-induced HMRD results in 5 possible infectious outcomes: asymptomatic, mild, moderate, severe to fatal episodes; while the symptomatic acute COVID-19 condition could manifest into 3 clinical phases: (i) hypoxia and hypoxemia (Warburg effect), (ii) hyperferritinemia ('cytokine storm'), and (iii) thrombocytosis (coagulopathy). The mean incubation period for COVID-19 onset was estimated to be 5.1 days, and most cases develop symptoms after 14 days. The mean viral clearance times were 24, 30, and 39 days for acute, severe, and ICU-admitted COVID-19 patients, respectively. However, about 25-70% of virus-free COVID-19 survivors continue to sustain virus-induced HMRD and exhibit a wide range of symptoms that are persistent, exacerbated, or new 'onset' clinical incidents, collectively termed as post-acute sequelae of COVID-19 (PASC) or long COVID. PASC patients experience several debilitating clinical condition(s) with >200 different and overlapping symptoms that may last for weeks to months. Chronic PASC is a cumulative outcome of at least 10 different HMRD-related pathophysiological mechanisms involving both virus-derived virulence factors and a multitude of innate host responses. Based on HMRD and virus-free clinical impairments of different human organs/systems, PASC patients can be categorized into 4 different clusters or sub-phenotypes: sub-phenotype-1 (33.8%) with cardiac and renal manifestations; sub-phenotype-2 (32.8%) with respiratory, sleep and anxiety disorders; sub-phenotype-3 (23.4%) with skeleto-muscular and nervous disorders; and sub-phenotype-4 (10.1%) with digestive and pulmonary dysfunctions. This narrative review elucidates the effects of viral hijack on host cellular machinery during SARS-CoV-2 infection, ensuing detrimental effect(s) of virus-induced HMRD on human metabolism, consequential symptomatic clinical implications, and damage to multiple organ systems; as well as chronic pathophysiological sequelae in virus-free PASC patients. We have also provided a few evidence-based, human randomized controlled trial (RCT)-tested, precision nutrients to reset HMRD for health recovery of PASC patients.

Markers of Epstein-Barr Virus Infection in Patients with Multiple Sclerosis

Viral infections have been suspected of being involved in the pathogenesis of certain autoimmune diseases for many years. Epstein-Barr virus (EBV), a DNA virus belonging to the Herpesviridae family, is thought to be associated with the onset and/or the progression of multiple sclerosis (MS), systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome and type 1 diabetes. The lifecycle of EBV consists of lytic cycles and latency programmes (0, I, II and III) occurring in infected B-cells. During this lifecycle, viral proteins and miRNAs are produced. This review provides an overview of the detection of EBV infection, focusing on markers of latency and lytic phases in MS. In MS patients, the presence of latency proteins and antibodies has been associated with lesions and dysfunctions of the central nervous system (CNS). In addition, miRNAs, expressed during lytic and latency phases, may be detected in the CNS of MS patients. Lytic reactivations of EBV can occur in the CNS of patients as well, with the presence of lytic proteins and T-cells reacting to this protein in the CNS of MS patients. In conclusion, markers of EBV infection can be found in MS patients, which argues in favour of a relationship between EBV and MS.

Role of Neural Stem Cells and Vitamin D Receptor (VDR)-Mediated Cellular Signaling in the Mitigation of Neurological Diseases

Specific stem cell-based therapies for treating Alzheimer's disease, Parkinson's disease, and schizophrenia are gaining importance in recent years. Accumulating data is providing further support by demonstrating the efficacy of neural stem cells in enhancing the neurogenesis in the aging brain. In addition to stem cells, recent studies have shown the efficacy of supplementing vitamin D in promoting neurogenesis and neuronal survival. Studies have also demonstrated the presence of mutational variants and single-nucleotide polymorphisms of the vitamin D receptor (VDR) in neurological disorders; however, implications of these mutations in the pathophysiology and response to drug treatment are yet to be explored. Hence, in this article, we have reviewed recent reports pertaining to the role of neural stem cells and VDR-mediated cellular signaling cascades that are involved in enhancing the neurogenesis through Wnt/β-catenin and Sonic Hedgehog pathways. This review benefits neurobiologists and pharmaceutical industry experts to develop stem cell-based and vitamin D-based therapies to better treat the patients suffering from neurological diseases.

Vitamin D: A Role Also in Long COVID-19?

Coronavirus disease 2019 (COVID-19) has quickly become a global pandemic. Reports from different parts of the world indicate that a significant proportion of people who have recovered from COVID-19 are suffering from various health problems collectively referred to as “long COVID-19”. Common symptoms include fatigue, shortness of breath, cough, joint pain, chest pain, muscle aches, headaches, and so on. Vitamin D is an immunomodulatory hormone with proven efficacy against various upper respiratory tract infections. Vitamin D can inhibit hyperinflammatory reactions and accelerate the healing process in the affected areas, especially in lung tissue. Moreover, vitamin D deficiency has been associated with the severity and mortality of COVID-19 cases, with a high prevalence of hypovitaminosis D found in patients with COVID-19 and acute respiratory failure. Thus, there are promising reasons to promote research into the effects of vitamin D supplementation in COVID-19 patients. However, no studies to date have found that vitamin D affects post-COVID-19 symptoms or biomarkers. Based on this scenario, this review aims to provide an up-to-date overview of the potential role of vitamin D in long COVID-19 and of the current literature on this topic.

Rays of immunity: Role of sunshine vitamin in management of COVID-19 infection and associated comorbidities

The catastrophic pandemic engendered due to the Novel coronavirus (COVID-19) outbreak which causes severe clinical afflictions on the respiratory system has severely high morbidity and mortality rates. The requirement of novel compounds is at utmost importance due to lack of targeted drug molecule to treat the afflictions and restrict the viral infection and for the usage of prophylactic treatment to avoid the spread of the infection is of utmost importance. Vitamin D is one such naturally available multifunctional molecule, which plays an eminent role in the immune system and instigation of numerous cellular pathways further promoting health benefits and enhancing the human quality of life. This article reviews the current standpoint scenario and future prevalence of vitamin D supplementation in the management of covid-19 patients. Novel findings of Vitamin D suggest that along with regulation of cell growth, neuroprotective and mood-stabilizing effects, it regulates the immune response also modulate cytokine Interleukin-6 (IL-6) by inducing progesterone-induced blocking factor (PIBF), given the IL-6 levels are considerably high in COVID-19 patients which increases the further complications. Vitamin D also have its effect on angiotensin converting enzyme (ACEII) inhibitor through which the COVID-19 virus makes cell entry. Numerous research data elucidate the play of Vitamin D, in complications of COVID-19 including the most common comorbid conditions, neurological manifestations and immunological aspects makes it an ideal molecule for adjuvant therapy. Including Vitamin D as add-on therapy in the management of COVID-19 might aid the arrest of infection and helps fight this arduous epidemic.

Low vitamin D exposure and risk of nasopharyngeal carcinoma: Observational and genetic evidence from a multicenter case-control study

BACKGROUND & AIMS

Little is known about the risk of nasopharyngeal carcinoma (NPC) in relation to vitamin D exposure. The aim of this study was to examine the associations of NPC risk with serum level of 25-hydroxyvitamin D (25OHD) and genetic predicted 25OHD, and potential effect modification by several putative risk factors of NPC.

METHODS

Our multicenter case-control study in Hong Kong recruited 815 NPC cases and 1502 frequency-matched (by sex and age) hospital controls from five major regional hospitals, and recruited 299 healthy subjects from blood donation centers (2014-2017). Circulating level of 25-hydroxyvitamin D (25OHD) and genetic predicted 25OHD (rs12785878, rs11234027, rs12794714, rs4588 and rs6013897) were measured by validated enzyme immunoassay and the iPLEX assay on the MassARRAY System, respectively. Data were also collected on demographics, lifestyle factors, ultraviolet radiation exposure, and potential confounders using a computer-assisted, self-administered questionnaire with satisfactory test-retest reliability. Unconditional logistic regression models were used to estimate ORs and 95% CIs.

RESULTS

Despite no significant association of NPC risk with circulating 25OHD and genetic predicted 25OHD, there was evidence for an inverse association in participants with normal body mass index (between 18.5 and 27.5) across categories of 25OHD (P_trend = 0.003), and a positive association in those with low socioeconomic status across categories based on the genetic score (P_trend = 0.005). In addition, risk of NPC diagnosed at an early stage was higher for genetically lower 25OHD level (adjusted OR = 3.09, 95% CI = 1.04-9.21, P_trend = 0.022).

CONCLUSIONS

Findings of this first comprehensive study to investigate the positive association of NPC risk with vitamin D deficiency need to be confirmed and be best interpreted with results of further similar studies. Our findings may inform possible etiological mechanisms of the associations with several putative risk/protective factors of NPC.

Illuminating the in vitro effects of Epstein-Barr virus and vitamin D on immune response in multiple sclerosis patients

Given the complexity of immune complex diseases including multiple sclerosis (MS) and the plausible interactions between different risk factors, delineating the interplay between them would be imperative. The current study aimed to evaluate the in vitro effects of Epstein-Barr virus (EBV) and vitamin D on immune response in MS patients and healthy controls. The status of vitamin D and EBV load was evaluated using multiple techniques. In vitro EBV-infected peripheral blood mononuclear cells (PBMCs), in the presence or absence of vitamin D, were checked for IL-10, IFN-γ, and vitamin D receptor. MS patients showed significantly higher plasma levels of 1,25-(OH)2D but not 25-OHD, increased EBV load, and lower levels of vitamin D receptor (VDR) expression compared with healthy controls. Interestingly, an inverse correlation was observed between VDR expression and EBV load in PBMCs. Indeed, the levels of IFN-γ and IL-10 production were significantly higher in supernatant collected from in vitro EBV-infected PBMCs in MS patients compared with controls. While all vitamin D-treated PBMCs showed reduced levels of IFN-γ production, in vitro treatment of vitamin D showed no influence in IL-10 production. EBV and vitamin D were found to exert opposite in vitro effects on immune dysregulation in these patients. Our results highlight the complex interactions of different risk factors with immune system.

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.

Solar Ultraviolet Radiation and Vitamin D Deficiency on Epstein-Barr Virus Reactivation: Observational and Genetic Evidence From a Nasopharyngeal Carcinoma-Endemic Population

Background

We investigated the relationship of Epstein-Barr virus viral capsid antigen (EBV VCA-IgA) serostatus with ambient and personal ultraviolet radiation (UVR) and vitamin D exposure.

Methods

Using data from a multicenter case-control study, we included 1026 controls subjects in 2014–2017 in Hong Kong, China. Odds ratios (ORs) and 95% confidence intervals (CIs) of the association between UVR exposure and EBV VCA-IgA (seropositivity vs seronegativity) were calculated using unconditional logistic regression models adjusted for potential confounders.

Results

We observed a large increase in seropositivity of EBV VCA-IgA in association with duration of sunlight exposures at both 10 years before recruitment and age 19–30 years (adjusted OR = 3.59, 95% CI = 1.46–8.77; and adjusted OR = 2.44, 95% CI = 1.04–5.73 for ≥8 vs <2 hours/day; P for trend = .005 and .048, respectively). However, no association of EBV VCA-IgA serostatus with other indicators of UVR exposure was found. In addition, both circulating 25-hydroxyvitamin D (25OHD) and genetic predicted 25OHD were not associated with EBV VCA-IgA serostatus.

Conclusions

Our results suggest that personal UVR exposure may be associated with higher risk of EBV reactivation, but we did not find clear evidence of vitamin D exposure (observational or genetic), a molecular mediator of UVR exposure. Further prospective studies in other populations are needed to confirm this finding and to explore the underlying biological mechanisms. Information on photosensitizing agents, and serological markers of EBV, and biomarkers related to systemic immunity and inflammation should be collected and are also highly relevant in future studies.

The importance of vitamin d metabolism as a potential prophylactic, immunoregulatory and neuroprotective treatment for COVID-19

The coronavirus disease 2019 (COVID-19) pandemic has led to a declaration of a Public Health Emergency of International Concern by the World Health Organization. As of May 18, 2020, there have been more than 4.7 million cases and over 316,000 deaths worldwide. COVID-19 is caused by a highly infectious novel coronavirus known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), leading to an acute infectious disease with mild-to-severe clinical symptoms such as flu-like symptoms, fever, headache, dry cough, muscle pain, loss of smell and taste, increased shortness of breath, bilateral viral pneumonia, conjunctivitis, acute respiratory distress syndromes, respiratory failure, cytokine release syndrome (CRS), sepsis, etc. While physicians and scientists have yet to discover a treatment, it is imperative that we urgently address 2 questions: how to prevent infection in immunologically naive individuals and how to treat severe symptoms such as CRS, acute respiratory failure, and the loss of somatosensation. Previous studies from the 1918 influenza pandemic have suggested vitamin D's non-classical role in reducing lethal pneumonia and case fatality rates. Recent clinical trials also reported that vitamin D supplementation can reduce incidence of acute respiratory infection and the severity of respiratory tract diseases in adults and children. According to our literature search, there are no similar findings of clinical trials that have been published as of July 1st, 2020, in relation to the supplementation of vitamin D in the potential prevention and treatment for COVID-19. In this review, we summarize the potential role of vitamin D extra-renal metabolism in the prevention and treatment of the SARS-CoV-2 infection, helping to bring us slightly closer to fulfilling that goal. We will focus on 3 major topics here: 1. Vitamin D might aid in preventing SARS-CoV-2 infection: Vitamin D: Overview of Renal and Extra-renal metabolism and regulation. Vitamin D: Overview of molecular mechanism and multifaceted functions beyond skeletal homeostasis. Vitamin D: Overview of local immunomodulation in human infectious diseases. Anti-viral infection. Anti-malaria and anti-systemic lupus erythematosus (SLE). 2. Vitamin D might act as a strong immunosuppressant inhibiting cytokine release syndrome in COVID-19: Vitamin D: Suppression of key pro-inflammatory pathways including nuclear factor kappa B (NF-kB), interleukin-6 (IL-6), and tumor necrosis factor (TNF). 3. Vitamin D might prevent loss of neural sensation in COVID-19 by stimulating expression of neurotrophins like Nerve Growth Factor (NGF): Vitamin D: Induction of key neurotrophic factors. .

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.

A Brief Review of the Effects of Vitamin D on Multiple Sclerosis

Multiple sclerosis (MS) is characterized as an autoimmune disease affecting the central nervous system. It is one of the most common neurological disorders in young adults. Over the past decades, increasing evidence suggested that hypovitaminosis D is a contributing factor to the risk of developing MS. From different risk factors contributing to the development of MS, vitamin D status is of particular interest since it is not only a modifiable risk factor but is also associated with MS disease activity. MS patients with lower serum vitamin D concentrations were shown to have higher disease activity. However, this finding does not demonstrate causality. In this regard, prospective vitamin D supplementation studies missed statistical significance in its primary endpoints but showed promising results in secondary outcome measures or post hoc analyses. An explanation for missed primary endpoints may be underpowered trials. Besides vitamin D supplementation as a potential add-on to long-term immunotherapeutic treatment, a recent laboratory study of our group pointed toward a beneficial effect of vitamin D to improve the efficacy of glucocorticoids in relapse therapy. In the following article, we will briefly review the effects of vitamin D on MS by outlining its effects on the immune and nervous system and by reviewing the association between vitamin D and MS risk as well as MS disease activity. We will also review the effects of vitamin D supplementation on MS risk and MS disease activity.

Vitamin D, Autoimmune Disease and Rheumatoid Arthritis

Vitamin D has been reported to influence physiological systems that extend far beyond its established functions in calcium and bone homeostasis. Prominent amongst these are the potent immunomodulatory effects of the active form of vitamin D, 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). The nuclear vitamin D receptor (VDR) for 1,25-(OH)2D3 is expressed by many cells within the immune system and resulting effects include modulation of T cell phenotype to suppress pro-inflammatory Th1 and Th17 CD4+ T cells and promote tolerogenic regulatory T cells. In addition, antigen-presenting cells have been shown to express the enzyme 1α-hydroxylase that converts precursor 25-hydroxyvitamin D3 (25-OHD3) to 1,25-(OH)2D3, so that immune microenvironments are able to both activate and respond to vitamin D. As a consequence of this local, intracrine, system, immune responses may vary according to the availability of 25-OHD3, and vitamin D deficiency has been linked to various autoimmune disorders including rheumatoid arthritis (RA). The aim of this review is to explore the immune activities of vitamin D that impact autoimmune disease, with specific reference to RA. As well as outlining the mechanisms linking vitamin D with autoimmune disease, the review will also describe the different studies that have linked vitamin D status to RA, and the current supplementation studies that have explored the potential benefits of vitamin D for prevention or treatment of RA. The overall aim of the review is to provide a fresh perspective on the potential role of vitamin D in RA pathogenesis and treatment.

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.

EBNA1, EBNA2, and EBNA3 link Epstein-Barr virus and hypovitaminosis D in multiple sclerosis pathogenesis

A strong north-to-south gradient is observed in the distribution of multiple sclerosis (MS), hinting toward an environmental etiology. Vitamin D has been associated with a decreased incidence of MS and may explain, in part, the lower prevalence in tropical climates. However, the existence of MS epidemics implies the possibility of an infectious etiology. Epstein-Barr virus (EBV) infection precedes MS presentation in nearly all affected individuals. While the individual contribution of EBV, vitamin D deficiency, and specific risk genes to MS etiology is possible, their potential interaction is of great interest and may have a synergistic effect on the development of MS.

Towards a comprehensive etiopathogenetic and pathophysiological theory of multiple sclerosis

Background: Multiple sclerosis (MS) is a neurodegenerative disease caused by dysfunction of the immune system that affects the central nervous system (CNS). It is characterized by demyelination, chronic inflammation, neuronal and oligodendrocyte loss and reactive astrogliosis. It can result in physical disability and acute neurological and cognitive problems. Despite the gains in knowledge of immunology, cell biology, and genetics in the last five decades, the ultimate etiology or specific elements that trigger MS remain unknown. The objective of this review is to propose a theoretical basis for MS etiopathogenesis.Methods: Search was done by accessing PubMed/Medline, EBSCO, and PsycINFO databases. The search string used was "(multiple sclerosis* OR EAE) AND (pathophysiology* OR etiopathogenesis)". The electronic databases were searched for titles or abstracts containing these terms in all published articles between January 1, 1960, and June 30, 2019. The search was filtered down to 362 articles which were included in this review.Results: A framework to better understand the etiopathogenesis and pathophysiology of MS can be derived from four essential factors; mitochondria dysfunction (MtD) & oxidative stress (OS), vitamin D (VD), sex hormones and thyroid hormones. These factors play a direct role in MS etiopathogenesis and have a modulatory effect on many other factors involved in the disease.Conclusions: For better MS prevention and treatment outcomes, efforts should be geared towards treating thyroid problems, sex hormone alterations, VD deficiency, sleep problems and melatonin alterations. MS patients should be encouraged to engage in activities that boost total antioxidant capacity (TAC) including diet and regular exercise and discouraged from activities that promote OS including smoking and alcohol consumption.

Vitamin D Receptor Gene Polymorphisms Are Associated With Leprosy in Southern Brazil

Vitamin D, together with its nuclear receptor (VDR), plays an important role in modulating the immune response, decreasing the inflammatory process. Some polymorphisms of the VDR gene, such as BsmI (G>A rs1544410), ApaI (G>T rs7975232), and TaqI (T>C rs731236) could affect its stability and mRNA transcription activity, while FokI T>C (rs2228570) gives a truncated protein with three fewer amino acids and more efficiency in binding vitamin D. This study evaluated these four polymorphisms in the immunopathogenesis of leprosy in 404 patients and 432 control individuals without chronic or infectious disease in southern Brazil. When analyzing differences in the allele and genotype frequency of polymorphisms between patients (leprosy per se, multibacillary, and paucibacillary clinical forms) and controls, we found no statistically significant association. Regarding haplotype analysis, the bAt haplotype was associated with protection from leprosy per se (P = 0.004, OR = 0.34, CI = 0.16–0.71) and from the multibacillary clinical form (P = 0.005, OR = 0.30, CI = 0.13–0.70). In individuals aged 40 or more years, this haplotype has also showed protection against leprosy per se and multibacillary (OR = 0.26, CI = 0.09–0.76; OR = 0.26, CI = 0.07–0.78, respectively), while the BAt haplotype was a risk factor for leprosy per se in the same age group (OR = 1.34, CI = 1.04–1.73). In conclusion, despite having found no associations between the VDR gene polymorphisms with the development of leprosy, the haplotypes formed by the BsmI, ApaI, and TaqI polymorphisms were associated with leprosy per se and the multibacillary clinical form.

Identifying the culprits in neurological autoimmune diseases

The target organ of neurological autoimmune diseases (NADs) is the central or peripheral nervous system. Multiple sclerosis (MS) is the most common NAD, whereas Guillain-Barré syndrome (GBS), myasthenia gravis (MG), and neuromyelitis optica (NMO) are less common NADs, but the incidence of these diseases has increased exponentially in the last few years. The identification of a specific culprit in NADs is challenging since a myriad of triggering factors interplay with each other to cause an autoimmune response. Among the factors that have been associated with NADs are genetic susceptibility, epigenetic mechanisms, and environmental factors such as infection, microbiota, vitamins, etc. This review focuses on the most studied culprits as well as the mechanisms used by these to trigger NADs.

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Neurological autoimmune diseases are caused by a complex interaction between genes, environmental factors, and epigenetic deregulation.

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Infectious agents can cause an autoimmune reaction to myelin epitopes through molecular mimicry and/or bystander activation.

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Gut microbiota dysbiosis contributes to neurological autoimmune diseases.

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Smoking increases the risk of NADs through inflammatory signaling pathways, oxidative stress, and Th17 differentiation.

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Deficiency in vitamin D favors NAD development through direct damage to the central and peripheral nervous system.

Epstein-Barr virus (EBV) reactivation and therapeutic inhibitors

Epstein-Barr virus (EBV) is a ubiquitous human virus which infects almost all humans during their lifetime and following the acute phase, persists for the remainder of the life of the individual. EBV infects B lymphocytes leading to their immortalisation, with persistence of the EBV genome as an episome. In the latent phase, EBV is prevented from reactivating through efficient cytotoxic cellular immunity. EBV reactivates (lytic phase) under conditions of psychological stress with consequent weakening of cellular immunity, and EBV reactivation has been shown to occur in a subset of individuals with each of a variety of cancers, autoimmune diseases, the autoimmune-like disease, chronic fatigue syndrome/myalgic encephalitis and under other circumstances such as being an inpatient in an intensive care unit. Chronic EBV reactivation is an important mechanism in the pathogenesis of many such diseases, yet is rarely tested for in immunocompetent individuals. This review summarises the pathogenesis of EBV infection, EBV reactivation and its role in disease, and methods which may be used to detect it. Known inhibitors of EBV reactivation and replication are discussed, including drugs licensed for treatment of other herpesviruses, licensed or experimental drugs for various other indications, compounds at an early stage of drug development and nutritional constituents such as vitamins and dietary supplements.

Comorbidities in multiple sclerosis-a plea for interdisciplinary collaboration to improve the quality of life of MS patients

The negative influence of comorbidities on the quality of life of people with multiple sclerosis is evident and the problem is increasingly acknowledged by numerous international studies in long-term care. One therapeutic option would be an add-on therapy with vitamin D (VD), with the aim of achieving a therapeutically effective dose. The individually required VD dose must be tested, since the response to a certain dose is subject to variations between individuals. A possible toxicity with increased 1.25(OH)D3 (active VD metabolite) is largely prevented by increased activity of 24-hydroxylase (CYP24A1). Monitoring of serum VD levels as well as serum calcium and phosphate levels (optional Ca excretion in 24-hour urine, Ca creatinine ratio in urine) provides safety and is necessary because possible mutations on the (catabolic) CYP24A1 gene can lead to a partial or total loss of 24-hydroxylase activity and provoke hypercalcemia/hyperphosphatemia. The main therapeutic objective is to maintain functional and social independence by using drugs with a high safety profile. The prevention and optimal management of comorbidities can influence the quality of life of patients with MS (PwMS) when included in patient care. Adequate measures can reduce the burden of MS only if the risk of comorbidity is reduced through targeted monitoring, early detection and diagnosis. Such a strategy will contribute to influencing the premature mortality of patients with MS. If VD is recognized as a "multipurpose steroid hormone", it could also be used to maintain cognitive function and prevent premature possible dementia, especially as there is evidence that VD deficiency correlates with brain atrophy (hippocampus). At present, MS therapy is still a balancing act between therapeutically efficient action and the management of unexpected side effects, with VD add-on therapy being almost unproblematic and most likely to be accepted by PwMS.

Adverse events from large dose vitamin D supplementation taken for one year or longer

In recent years, clinical trials increasingly have given large doses of vitamin D supplements to investigate possible health benefits beyond bone at high 25-hydroxyvitamin D levels. However, there are few publications on the safety of high-dose vitamin D given long term. The study objective was to investigate the cumulative relative risk (RR) of total adverse events, kidney stones, hypercalcemia and hypercalciuria from ≥2800 IU/d vitamin D₂ or D₃ supplementation, followed for one year or more in randomized controlled trials (RCTs). A systematic review was conducted in Medline Ovid, EMBASE and Cochrane in March 2018 to update results of studies published since a previous review in October 2015. RCTs were included if they gave vitamin D₂ or D₃ at ≥2800 IU/d for at least one year and reported on total adverse events or at least one calcium-related adverse event. There were a total of 32 studies that met the inclusion criteria. Of these, only 15 studies (3150 participants) reported one or more event of the outcomes of interest. Long-term high-dose vitamin D supplementation did not increase total adverse events compared to placebo in 1731 participants from 10 studies (RR = 1.05; 95% CI = 0.88, 1.24; p = 0.61), nor kidney stones in 1336 participants from 5 studies (RR = 1.26; 95% CI = 0.35, 4.58; p = 0.72). However, there was a trend for vitamin D to increase risk of hypercalcemia in 2598 participants from 10 studies (RR = 1.93; 95% CI = 1.00, 3.73; p = 0.05); while its effect on hypercalciuria in only 276 participants from 3 studies was inconclusive (RR = 1.93; 95% CI = 0.83, 4.46; p = 0.12). In conclusion, one year or longer supplementation with a large daily, weekly or monthly dose of vitamin D₂ /D₃ did not significantly increase a risk of total adverse events or kidney stones, although there was a trend towards increased hypercalcemia, and possibly for hypercalciuria.

The role of Epstein-Barr virus in multiple sclerosis: from molecular pathophysiology to in vivo imaging

Multiple sclerosis (MS) is a disease of the central nervous system characterized by inflammation, demyelination, and neuronal damage. Environmental and genetic factors are associated with the risk of developing MS, but the exact cause still remains unidentified. Epstein-Barr virus (EBV), vitamin D, and smoking are among the most well-established environmental risk factors in MS. Infectious mononucleosis, which is caused by delayed primary EBV infection, increases the risk of developing MS. EBV may also contribute to MS pathogenesis indirectly by activating silent human endogenous retrovirus-W. The emerging B-cell depleting therapies, particularly anti-CD20 agents such as rituximab, ocrelizumab, as well as the fully human ofatumumab, have shown promising clinical and magnetic resonance imaging benefit. One potential effect of these therapies is the depletion of memory B-cells, the primary reservoir site where EBV latency occurs. In addition, EBV potentially interacts with both genetic and other environmental factors to increase susceptibility and disease severity of MS. This review examines the role of EBV in MS pathophysiology and summarizes the recent clinical and radiological findings, with a focus on B-cells and in vivo imaging. Addressing the potential link between EBV and MS allows the better understanding of MS pathogenesis and helps to identify additional disease biomarkers that may be responsive to B-cell depleting intervention.

Vitamin D in malaria: more hypotheses than clues

Vitamin D is a secosteroid hormone regulating calcium and phosphate metabolism, immune response and brain development. Low blood 25(OH)D levels have been reported in patients affected by infectious diseases caused by parasites, including malaria. Despite the high effectiveness of antimalarials, malaria is burdened with high morbidity and mortality, and the search for additional therapies is rapidly growing. Furthermore, available preventive measures have proved to be barely effective so far. Finding new prevention and therapy tools is a matter of urgency. Studies on animal models and humans have hypothesized some mechanisms by which the hormone can influence malaria pathogenesis, and the role of Vitamin D supplementation in preventing and treating this disease has been suggested. Few studies on the association between Vitamin D and malaria are available and disagreeing results have been reported. Studies in humans reporting an association between low 25(OH)D circulating levels and Malaria have a small sample size and observational study-set. Randomized controlled trials are needed in order to understand if Vitamin D administration might play a role in preventing and treating malaria.

Correlation of different cellular assays to analyze T cell-related cytokine profiles in vitamin D3-supplemented patients with multiple sclerosis

Different laboratory approaches have been exploited to analyze an effect of vitamin D₃ supplements on T cell cytokine profiles in multiple sclerosis, with poorly reproducible results. We assessed the correlation between intra-cellular flowcytometry analysis of CD4 T cell-enriched CD3⁺CD8^- lymphocytes after PMA/ionomycin stimulation directly ex-vivo or after 72 h pre-stimulation with anti-CD3, and cytokine levels excreted in culture supernatants. Pre-stimulation with anti-CD3 resulted in higher proportions of cells positive for IFN-γ, IL-17 A, IL-4, IL-10 and GM-CSF (all P < 0.001), but not TNF-α. Positive correlation between approaches was highly variable, but most eminent for IFN- γ and IL-4 (R = 0.608-0.612 and R = 0.677-0.777, resp., all P < 0.001). No effect of 16-weeks vitamin D₃ supplements on any outcome was found except for a decreased TNF-α concentration in culture supernatants. Choice of immune-assay is, apparently, a relevant confounder for the reproducibility of individual studies.

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.

Monthly high-dose vitamin D3 supplementation and self-reported adverse events in a 4-year randomized controlled trial

BACKGROUND

The use of high-dose vitamin D supplementation has increased in recent years. However, relatively little is known about the safety of long-term high doses.

AIMS

To investigate the safety of a monthly high-dose of vitamin D₃ supplementation taken for up to 4 years.

METHODS

Data were collected in a randomized, double blind, placebo-controlled trial of 5108 adults aged 50-84 years old from Auckland, New Zealand. Participants were given monthly doses of 100,000 IU vitamin D₃ or placebo, for a median of 3.3 years (range 2.5-4.2 years). They answered an open-ended question in a monthly questionnaire about any adverse events they attributed to the study capsules, which were coded blindly. Incidence rates per person months were calculated for categories of adverse events. Cox regression model used to calculate hazard ratio of time to first adverse-event.

RESULTS

In total, 419 (16.5%) participants taking vitamin D and 399 (15.8%) taking placebo reported ≥1 adverse event. Compared to placebo, the hazard ratio (HR) of reporting first adverse event in the vitamin D group was 1.03 (95% CI: 0.90, 1.18; p = 0.63). Despite a slightly higher incidence of recurrent adverse events in vitamin D arm, the incidence rate ratio (1.17) was not significantly higher in vitamin D (95% CI: 0.97, 1.41; p = 0.10). All regression results were adjusted for age, sex, and ethnicity. There was no difference between study arms in terms of participants' allocation perception (p = 0.52).

CONCLUSION

Monthly supplementation of 100,000 IU vitamin D3 for a median of 3.3 years did not affect participant-reported adverse events.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: ACTRN12611000402943; https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?ACTRN=ACTRN12611000402943.

Study of the possible link of 25-hydroxyvitamin D with Epstein-Barr virus and human herpesvirus 6 in patients with multiple sclerosis

BACKGROUND AND PURPOSE

Although the causes of multiple sclerosis (MS) remain partially unknown, environmental and genetic factors are thought to play a role in its aetiopathogenesis. Hypovitaminosis D, Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV-6) infections have been described as possible MS triggers. Our aim was to analyse the possible link between 25-hydroxyvitamin D [25(OH)D] and viruses in patients with MS.

METHODS

We included 482 patients with MS in a 2-year study. Serum samples were collected to analyse 25(OH)D levels and, according to sample availability, antibody titres against EBV and HHV-6 by enzyme-linked immunosorbent assay. DNA was extracted from blood in order to analyse EBV and HHV-6 viral load by quantitative real-time polymerase chain reaction and to genotype MS-related single nucleotide polymorphisms (rs3135388, rs2248359 and rs12368653) when possible.

RESULTS

The 25(OH)D levels were significantly higher in the first semester of the year than in the second. Carriers of the risk allele rs2248359-C showed lower 25(OH)D levels than non-carriers. For EBV, viral load was significantly higher when 25(OH)D levels were low, demonstrating an inverse correlation between 25(OH)D levels and EBV load.

CONCLUSIONS

The 25(OH)D levels could be involved in the regulation of EBV replication/reactivation in patients with MS.

The role of UV radiation and vitamin D in the seasonality and outcomes of infectious disease

The seasonality of infectious disease outbreaks suggests that environmental conditions have a significant effect on disease risk. One of the major environmental factors that can affect this is solar radiation, primarily acting through ultraviolet radiation (UVR), and its subsequent control of vitamin D production. Here we show how UVR and vitamin D, which are modified by latitude and season, can affect host and pathogen fitness and relate them to the outcomes of bacterial, viral and vector-borne infections. We conducted a thorough comparison of the molecular and cellular mechanisms of action of UVR and vitamin D on pathogen fitness and host immunity and related these to the effects observed in animal models and clinical trials to understand their independent and complementary effects on infectious disease outcome. UVR and vitamin D share common pathways of innate immune activation primarily via antimicrobial peptide production, and adaptive immune suppression. Whilst UVR can induce vitamin D-independent effects in the skin, such as the generation of photoproducts activating interferon signaling, vitamin D has a larger systemic effect due to its autocrine and paracrine modulation of cellular responses in a range of tissues. However, the seasonal patterns in infectious disease prevalence are not solely driven by variation in UVR and vitamin D levels across latitudes. Vector-borne pathogens show a strong seasonality of infection correlated to climatic conditions favoring their replication. Conversely, pathogens, such as influenza A virus, Mycobacterium tuberculosis and human immunodeficiency virus type 1, have strong evidence to support their interaction with vitamin D. Thus, UVR has both vitamin D-dependent and independent effects on infectious diseases; these effects vary depending on the pathogen of interest and the effects can be complementary or antagonistic.

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.

High-dose of vitamin D supplement is associated with reduced susceptibility of monocyte-derived macrophages to dengue virus infection and pro-inflammatory cytokine production: An exploratory study

BACKGROUND

Dengue, one the most important public health problems in tropical and subtropical areas, is the most important mosquito-borne viral infection in humans. In the absence of effective treatment and vaccine against dengue, the active form of vitamin D could play a central role in protection against dengue virus (DENV), the causal agent of dengue. Recently we reported that monocyte-derived macrophages (MDMs) differentiated in the presence of vitamin D, in addition to expressing lower levels of mannose receptor, are less susceptible to DENV infection and produce low levels of pro-inflammatory cytokines, compared to MDMs differentiated in the absence of vitamin D.

OBJECTIVE

The aim of this study was to determine that oral vitamin D supplementation exerts an effect on DENV susceptibility and pro-inflammatory cytokine production in MDMs.

METHODS

Healthy individuals were supplemented with 1000 or 4000 international units (IU)/day of vitamin D during 10days. Before and after vitamin D supplementation, a peripheral blood (PB) sample was taken and the monocytes recovered were used to obtain MDMs and were challenged with DENV-2. Furthermore, the expression of genes encoding vitamin D receptor (VDR), CYP24A1 and CAMP were analyzed using real-time quantitative PCR.

RESULTS

The data indicate that macrophages differentiated from monocytes obtained from healthy donors who received higher doses of vitamin D (4000IU/day), exhibited higher resistance to DENV-2 infection and produced a significant decrease of pro-inflammatory cytokines and high production of interleukin-10 (IL-10). Furthermore, a significant decrease in intracellular toll-like receptor (TLR) and CAMP mRNA was observed.

CONCLUSION

A supplement of 4000IU/day of vitamin D may represent an adequate dose to control dengue progression and DENV replication. Although the results of our study suggest that the vitamin D status can influence the immune response, further studies are needed to determine the feasibility of vitamin D as anti-DENV agent and immune modulator.

Managing Epstein-Barr virus and other risk factors in MS-Future perspectives

Here, we discuss the rationale and feasibility of treatment directed against the modifiable risk factors in multiple sclerosis. The established environmental risk factors vitamin D insufficiency, cigarette smoke exposure, adolescence overweight, and Epstein-Barr virus infection are reviewed. Already available measures to target these risk factors are discussed.

Exploring the effect of vitamin D3 supplementation on the anti-EBV antibody response in relapsing-remitting multiple sclerosis

Background:

Epstein–Barr virus (EBV) infection and vitamin D insufficiency are potentially interacting risk factors for multiple sclerosis (MS).

Objectives:

To investigate the effect of high-dose vitamin D₃ supplements on antibody levels against the EBV nuclear antigen-1 (EBNA-1) in patients with relapsing-remitting multiple sclerosis (RRMS) and to explore any underlying mechanism affecting anti-EBNA-1 antibody levels.

Methods:

This study utilized blood samples from a randomized controlled trial in RRMS patients receiving either vitamin D₃ (14,000 IU/day; n = 30) or placebo (n = 23) over 48 weeks. Circulating levels of 25-hydroxyvitamin-D, and anti-EBNA-1, anti-EBV viral capsid antigen (VCA), and anti-cytomegalovirus (CMV) antibodies were measured. EBV load in leukocytes, EBV-specific cytotoxic T-cell responses, and anti-EBNA-1 antibody production in vitro were also explored.

Results:

The median antibody levels against EBNA-1, but not VCA and CMV, significantly reduced in the vitamin D₃ group (526 (368–1683) to 455 (380–1148) U/mL) compared to the placebo group (432 (351–1280) to 429 (297–1290) U/mL; p = 0.023). EBV load and cytotoxic T-cell responses were unaffected. Anti-EBNA-1 antibody levels remained below detection limits in B-cell cultures.

Conclusion:

High-dose vitamin D₃ supplementation selectively reduces anti-EBNA-1 antibody levels in RRMS patients. Our exploratory studies do not implicate a promoted immune response against EBV as the underlying mechanism.

High dose vitamin D supplementation does not affect biochemical bone markers in multiple sclerosis - a randomized controlled trial

Background

People with multiple sclerosis have high risk of osteoporosis and fractures. A poor vitamin D status is a risk factor for MS, and vitamin D supplementation has been recommended both to prevent MS progression and to maintain bone health.

Methods

We assessed the effect of 20,000 IU vitamin D₃ weekly compared to placebo on biochemical markers of bone metabolism in 68 persons with relapsing remitting multiple sclerosis.

Results

Serum levels of 25-hydroxyvitamin D more than doubled in the vitamin D group, and parathyroid hormone decreased in the vitamin D group compared to the placebo group at week 48 and week 96. There was however no effect on bone formation as measured by procollagen type I N propeptide (PINP), or on bone resorption as measured by C-terminal cross-linking telopeptide of type I collagen (CTX1). Neither PINP nor CTX1 predicted bone loss from baseline to week 96.

Conclusions

These findings corroborate the previously reported lack of effect of weekly high dose vitamin D supplementation on bone mass density in the same patients, and suggest that such vitamin D supplementation does not prevent bone loss in persons with MS who are not vitamin D deficient.

Trial registration

The trial was registered at ClinicalTrials.gov on April 4 2008, registration number NCT00785473.

Vitamin D and multiple sclerosis: An update

The most recent findings linking exposure to sun and vitamin D insufficiency to multiple sclerosis (MS) are reviewed. Due to insufficient sunshine and changing lifestyles, hypovitaminosis D is widespread in temperate countries. Numerous epidemiological studies have strongly suggested that sunshine and vitamin D insufficiency contributes to MS risk in these countries. Moreover, several large genetic studies in MS patients have recently stated unequivocally that diverse abnormalities involving vitamin D metabolism are related to the risk of the disease. The important implications of such results are discussed here. Then, the interactions of hypovitaminosis D with the other genetic and environmental protective and risk factors, such as the allele HLA DRB1*1501, Epstein-Barr virus infection, obesity, smoking and sexual hormones, are summarized. Vitamin D insufficiency and sufficiency could be a risk and a protective factor, respectively, among many other factors possibly continuously modulating the global MS risk from the mother's pregnancy to the triggering of MS in adulthood. However, many interactions between these different factors occur more particularly between conception and the end of adolescence, which corresponds to the period of maturation of the immune system and thymus and may be related to the dysimmune nature of the disease. The main mechanisms of action of vitamin D in MS appear to be immunomodulatory, involving the various categories of T and B lymphocytes in the general immune system, but neuroprotector and neurotrophic mechanisms could also be exerted at the central nervous system level. Furthermore, several controlled immunological studies performed in MS patients have recently confirmed that vitamin D supplementation has multiple beneficial immunomodulatory effects. However, there is still an enduring absence of major conclusive randomized clinical trials testing vitamin D supplementation in MS patients because of the quasi-insurmountable practical difficulties that exist nowadays in conducting and completing over several years such studies involving the use of a vitamin. Nevertheless, it should be noted that similar robust statistical models used in five different association studies have already predicted a favorable vitamin D effect reducing relapses by 50-70%. If there is now little doubt that vitamin D exerts a beneficial action on the inflammatory component of MS, the results are as yet much less clear for the progressive degenerative component. Lastly, until more information becomes available, vitamin D supplementation of MS patients, using a moderate physiological dose essentially correcting their vitamin insufficiency, is recommended.