Association between hypovitaminosis D and systemic sclerosis: True or fake?

Immunomodulatory actions of vitamin D in various immune-related disorders: a comprehensive review

For many years, vitamin D has been acknowledged for its role in maintaining calcium and phosphate balance. However, in recent years, research has assessed its immunomodulatory role and come up with conflicting conclusions. Because the vitamin D receptor is expressed in a variety of immune cell types, study into the precise role of this molecule in diseases, notably autoimmune disorders, has been made possible. The physiologically activated version of vitamin D also promotes a tolerogenic immunological condition in addition to modulating innate and acquired immune cell responses. According to a number of recent studies, this important micronutrient plays a complex role in numerous biochemical pathways in the immune system and disorders that are associated with them. Research in this field is still relatively new, and some studies claim that patients with severe autoimmune illnesses frequently have vitamin D deficiencies or insufficiencies. This review seeks to clarify the most recent research on vitamin D's immune system-related roles, including the pathophysiology of major disorders.

An Update on the Effects of Vitamin D on the Immune System and Autoimmune Diseases

Vitamin D intervenes in calcium and phosphate metabolism and bone homeostasis. Experimental studies have shown that 1,25-dihydroxyvitamin D (calcitriol) generates immunologic activities on the innate and adaptive immune system and endothelial membrane stability. Low levels of serum 25-hydroxyvitamin D (25(OH)D) are associated with an increased risk of developing immune-related diseases such as psoriasis, type 1 diabetes, multiple sclerosis, and autoimmune diseases. Various clinical trials describe the efficacy of supplementation of vitamin D and its metabolites for treating these diseases that result in variable outcomes. Different disease outcomes are observed in treatment with vitamin D as high inter-individual difference is present with complex gene expression in human peripheral blood mononuclear cells. However, it is still not fully known what level of serum 25(OH)D is needed. The current recommendation is to increase vitamin D intake and have enough sunlight exposure to have serum 25(OH)D at a level of 30 ng/mL (75 nmol/L) and better at 40–60 ng/mL (100–150 nmol/L) to obtain the optimal health benefits of vitamin D.

Serum Vitamin D as a Biomarker in Autoimmune, Psychiatric and Neurodegenerative Diseases

Vitamin D is a steroid hormone regulating calcium-phosphorus homeostasis, immune response and brain function. In the past thirty years, an increasing number of cohort studies, meta-analyses and randomized controlled trials (RTCs) evaluated the serum levels of 25-hydroxyvitamin D [25(OH)D], which is considered the Vitamin D status biomarker, in patients affected by neurological, psychiatric and autoimmune diseases. Although an association between low 25(OH)D serum levels and the prevalence of these diseases has been found, it is still unclear whether the serum 25(OH)D measurement can be clinically useful as a biomarker for diagnosis, prognosis and predicting treatment response in neurodegeneration, mental illness and immune-mediated disorders. The lack of standardized data, as well as discrepancies among the studies (in the analytical methods, cut-offs, endpoints and study sets), weakened the findings achieved, hindered pooling data, and, consequently, hampered drawing conclusions. This narrative review summarizes the main findings from the studies performed on serum 25(OH)D in neurological, psychiatric and autoimmune diseases, and clarifies whether or not serum 25(OH)D can be used as a reliable biomarker in these diseases.

Presepsin and Midregional Proadrenomedullin in Pediatric Oncologic Patients with Febrile Neutropenia

OBJECTIVE

In this study, we investigated the roles of presepsin (PSP) and midregional proadrenomedullin (mr-proADM) in children with febrile neutropenia (FN) due to chemotherapy.

METHODS

We assessed 36 FN episodes in 26 children. Patients were classified into bacteremia (B) and fever of unknown origin (FUO) groups. We evaluated PSP and mr-proADM at admission (T0), after 24/48 h (T1), and after 5 days (T2).

RESULTS

PSP and mr-proADM levels were elevated at T0 and significantly decreased at T2. mr-proADM levels did not significantly differ between the B and FUO groups. PSP levels significantly differed between the B and FUO groups only at T1. Both PSP and mr-proADM levels at T0 were a predictor of length of hospital stay but not of the duration of fever. Finally, receiver operating characteristic curve analysis showed that PSP and mr-proADM had low diagnostic accuracy for blood culture positivity.

CONCLUSION

PSP and mr-proADM display poor clinical usefulness for FN in oncologic children.

Vitamin D and Cytokine Profiles in Patients With Systemic Sclerosis

INTRODUCTION

Hypovitaminosis D has been frequently described in systemic sclerosis (SSc). Cytokines are important mediators of tissue damage and clinical dysfunction in SSc and may be influenced by vitamin D levels.

OBJECTIVE

To evaluate the serum levels of vitamin D and its correlation with the clinical features and cytokine profiles in SSc patients.

METHODS

Case-control study, including 50 SSc patients and 35 healthy non matched controls. Serum levels of 25(OH) vitamin D were measured by chemiluminescence assay, and serum concentrations of interleukin 2 (IL-2), IL-4, IL-6, IL-10, tumor necrosis factor, and interferon γ were determined by flow cytometry.

RESULTS

Fourteen patients (28%) had diffuse cutaneous SSc, 94% were female, 80% European derived, with a mean age of 57.2 ± 12.8 years. The serum vitamin D levels in SSc patients were 23.9 ± 8.5 ng/mL and 30.2 ± 6.2 ng/mL in the control group (standardized mean difference -6.19; 95% confidence interval, -9.9 to -2.3; p = 0.002), despite the more frequent supplementation of vitamin D in SSc patients (p = 0.014). No significant associations were found among vitamin D concentrations and cytokine levels. Serum levels of IL-6 were significantly elevated in SSc patients (p = 0.024) and were positively correlated with the modified Rodnan skin score (rs = 0.291, p =0.041).

CONCLUSIONS

Despite lower vitamin D levels in SSc patients, there was no clear association with any cytokine. Serum levels of IL-6 were significantly elevated and positively correlated with the extent of skin involvement in SSc patients.

Dualities of the vitamin D in systemic sclerosis: a systematic literature review

BACKGROUND

Systemic sclerosis (SSc) is a chronic disease characterized by autoimmunity, vasculopathy, and visceral and cutaneous fibrosis. Vitamin D has several functions in the immunological system, and different studies have suggested a potential role in triggering autoimmune diseases. Patients with SSc may present with low serum levels of vitamin D, but the association between hypovitaminosis D and disease onset or any clinical manifestation is still obscure. Our goal was to verify the causal relationship between hypovitaminosis D and SSc onset or any particular clinical manifestation in the literature.

METHODS

A systematic literature review was performed through February 24th, 2021 on Pubmed, Lilacs/BIREME, and Cochrane databases. The eligible studies were read in full text, and, in the absence of exclusion criteria, were included in this review after consensus between two reviewers.

RESULTS

Forty articles met the eligibility criteria and the main results of each study are described. In most studies, SSc patients showed a higher prevalence of vitamin D deficiency and insufficiency compared to controls. Additionally, in some reports serum levels of vitamin D were inversely correlated with the severity of SSc. Oral supplementation did not seem to affect serum levels of vitamin D. Four of the included studies were with experimental models.

CONCLUSION

In conclusion, vitamin D deficiency seems to have a role in susceptibility to SSc, as well as in the clinical manifestations of the disease.

Combination of vitamin D and dipeptidyl peptidase-4 inhibitors (VIDPP-4i) as an immunomodulation therapy for autoimmune diabetes

Type 1 diabetes (T1D) and latent autoimmune diabetes in adults (LADA) represent the most common types of autoimmune diabetes and are characterized by different age of onset, degrees of immune-mediated destruction of pancreatic beta cells and rates of disease progression towards insulin dependence. Several immunotherapies aimed to counteract autoimmune responses against beta cells and preserve beta-cell function are currently being investigated, particularly in T1D. Preliminary findings suggest a potential role of combination therapy with vitamin D and dipeptidyl peptidase-4 (DPP-4) inhibitors (VIDPP-4i) in preserving beta-cell function in autoimmune diabetes. This manuscript aims to provide a comprehensive overview of the immunomodulatory properties of vitamin D and DPP-4 inhibitors, as well as the rationale for investigation of their combined use as an immunomodulation therapy for autoimmune diabetes.

Vitamin D3 as possible diagnostic marker of Eating Disorders

Purpose

Eating Disorders (EDs) refer to a group of psychiatric conditions in which disorderly food intake results in impaired psychological functioning or physical health. Nowadays, these disorders represent an increasing problem in modern society. There are no universally validated clinical parameters to confirm, disprove or simply help to identify EDs except for diagnostic criteria on psychiatric basis. The aim of this study was the assessment of Vitamin D3 level in patients with EDs to understand if it might be a valid clinical biochemistry parameter useful as prognostic marker.

Methods

The sample consists of 28 female patients, who suffer from EDs. Blood samples were examined in terms of blood count, glucose, cholesterol and Vitamin D3 levels. The other clinical biochemistry parameters were analysed to understand if the Vitamin D3 was the only altered parameter.

Results

The parameters that appear altered are glycemia, cholesterol and, in particular, Vitamin D3. Significant results were obtained comparing controls with restrictive-type anorexia nervosa (p value= 0,003) and with purging-type anorexia nervosa (p value= 0,007).

Conclusion

There are currently no universally validated and diagnostic reliable clinical biochemistry parameters for EDs but, in the light of the findings, but our research indicates the potential use of Vitamin D3 as a biomarker for anorexia nervosa.

Level of evidence

Level III: Evidence obtained from a single-center cohort study.

Vitamin D and Genetic Susceptibility to Multiple Sclerosis

Multiple sclerosis (MS) is an autoimmune disease affecting the central nervous system (CNS), resulting from the interaction among genetic, epigenetic, and environmental factors. Vitamin D is a secosteroid, and its circulating levels are influenced by environment and genetics. In the last decades, research data on the association between MS and vitamin D status led to hypothesize a possible role for hypovitaminosis D as a risk factor for MS. Some gene variants encoding proteins involved in vitamin D metabolism, transport, and function, which are responsible for vitamin D status alterations, have been related to MS susceptibility. This review explores the current literature on the influence of vitamin D-related genes in MS susceptibility, reporting all single-nucleotide polymorphisms (SNPs) investigated to date in 12 vitamin D pathway genes. Among all, the gene codifying vitamin D receptor (VDR) is the most studied. The association between VDR SNPs and MS risk has been reported by many Authors, with a few studies producing opposite results. Other vitamin D-related genes (including DHCR7/NADSYN1, CYP2R1, CYP27A1, CYP3A4, CYP27B1, CYP24A1, Megalin-DAB2-Cubilin, FGF-23, and Klotho) have been less investigated and achieved more conflicting evidence. Taken together, findings from the studies reviewed cannot clarify whether and to what extent vitamin D-related gene variants can influence MS risk.

Genetic variants of vitamin D metabolism-related DHCR7/NADSYN1 locus and CYP2R1 gene are associated with clinical features of Parkinson's disease

PURPOSE/AIM OF THE STUDY

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Vitamin D deficiency is suggested to be related to PD. A genome-wide association study indicated that genes involved in vitamin D metabolism affect vitamin D levels. Among these genes, single nucleotide polymorphisms (SNPs) of the vitamin D receptor (VDR) and vitamin D binding protein (VDBP/GC) genes have also been demonstrated to be associated with PD risk. Our aim was to investigate the relevance of SNPs within the 7-dehydrocholesterol reductase/nicotinamide adenine dinucleotide synthetase 1 (DHCR7/NADSYN1) locus and vitamin D 25-hydroxylase (CYP2R1) gene, which encode important enzymes that play a role in the vitamin D synthesis pathway, with PD and its clinical features.

MATERIALS AND METHODS

Genotypes of 382 PD patients and 240 cognitively healthy individuals were evaluated by a LightSNiP assay for a total of 10 SNPs within the DHCR7/NADSYN1 locus and CYP2R1 gene.

RESULTS

There were no significant differences in the allele and genotype distributions of any of the SNPs between any patient groups and healthy subjects. However, our results indicated that all of the SNPs within the DHCR7/NADSYN1 locus and CYP2R1 gene, except rs1993116, were associated with clinical motor features of PD including initial predominant symptom, freezing of gait (FoG) and falls as well as disease stage and duration of the disease.

CONCLUSIONS

In conclusion, genetic variants of the DHCR7/NADSYN1 locus and the CYP2R1 gene might be related to the inefficient utilization of vitamin D independent from vitamin D levels, and it might result in differences in the clinical features of PD patients.

Network pharmacology strategy for predicting the correlation of Systemic Scleroderma with Vitamin D deficiency

The deficiency of Vitamin D (V_D) is a common symptom of systemic scleroderma (SSc), but the correlation of V_D deficiency and SSc is not completely clear. Therefore, a strategy based on network pharmacology was designed to explore the correlation of V_D deficiency and SSc. After a series of network construction and analysis, 5 integrins were predicated as the kernel targets in the correlation of V_D deficiency and SSc, including ITGA5, ITGA4, ITGB3, ITGB1 and ITGAV. The crucial pathways in which the kernel targets participated were mainly involved in the function of immune, vascular and internal organ. The regulation modules of crucial pathways were closely related to the biological processes in the pathological of SSc. Taken together, the analysis predicted that the deficiency of V_D might affect the pathological of SSc through the mediation of these integrins. Therefore, targeted regulation of these integrins might be an effective therapy against SSc.

Serum vitamin D status following pediatric cardiac surgery and association with clinical outcome

Our aim is to determine the prevalence of vitamin D deficiency in children with congenital heart disease (CHD). In addition, we demonstrated the effect of cardiopulmonary bypass (CPB) on vitamin D, parathyroid hormone (PTH), and calcium levels. The association between perioperative vitamin D levels and postoperative clinical outcomes has been explored. A prospective observational study was conducted from February 2018 to June 2019 on 69 children undergoing elective surgery for CHD under CPB. Blood samples were collected preoperatively, immediate postoperatively, and 24 h postoperatively. Vitamin D deficiency was present in 34 (49.3%) patients preoperatively and 63 (91.3%) patients immediately postoperative. We identified 42.03% decline of 25(OH)D immediately postoperative. Changes in ionized calcium (iCa) concentrations were accompanied by reciprocal alterations in PTH concentrations. Lower postoperative 25(OH)D was associated with higher maximum vasoactive inotropic score (VIS) in the first 24 h postoperative (r = - 0.259, p = 0.03).Conclusion: Vitamin D deficiency is common in children with CHD and the majority are vitamin D deficient following cardiac surgery with acute decline of serum 25(OH)D after CPB. Lower postoperative vitamin D levels in children undergoing cardiac surgery are associated with the need for increasing the inotropic support.What is Known:• Vitamin D is a pleiotropic hormone, important for calcium homeostasis.• Vitamin D deficiency might affect the outcome in critically ill patients.What is New:• Cardiopulmonary bypass causes acute decline of vitamin D in children.• Lower postoperative vitamin D is associated with higher inotropic support.

Vitamin D and connective tissue diseases

OBJECTIVE AND DESIGN

Recently, many studies have shown that the biologically active form of vitamin D-1,25(OH)₂ D-is involved in many biological processes, including immune system modulation, and patients affected by various autoimmune diseases, such as connective tissue diseases (CTD), showed low levels of vitamin D. It is not clear if vitamin D deficiency is involved in the pathogenesis of autoimmune diseases or it is a consequence.

MATERIAL

We carried out a review of literature to summarize the existing connections between 25-OH vitamin D and CTD.

METHODS

We searched for articles on PubMed by keywords: vitamin D, connective tissue diseases, systemic lupus erythematosus, Sjogren's syndrome, systemic sclerosis, undifferentiated connective tissue disease.

RESULTS

The relationship between vitamin D and CTD is still not very clear, despite many studies having been performed and some data suggest a connection between these diseases and 25-OH vitamin D levels.

CONCLUSIONS

The limitations of the study, such as the heterogeneity of patients, methods used to measure vitamin D serum concentration and other biases, do not lead to unequivocal results to demonstrate a direct link between low vitamin D serum levels and autoimmune diseases. Further studies are needed to resolve conflicting results.

Vitamin D and Multiple Sclerosis: An Open-Ended Story

Multiple Sclerosis (MS) is a chronic inflammatory autoimmune disease of the Central Nervous System (CNS). Genetic, epigenetic and environmental factors interact together, contributing to the complex pathogenesis of the disease. In the last decades, the role of hypovitaminosis D on MS risk was hypothesised. Several factors drive the regulation of vitamin D status, including genetics. The current review summarises the literature evidence on the association between vitamin D and MS, with a focus on the genetic polymorphisms in vitamin D-related genes. The variants of the genes codifying Vitamin D Receptor (VDR), Vitamin D Binding Protein (VDBP) and CYP enzymes have been investigated, but the findings are controversial. Only a few studies have addressed the role of DHCR7 polymorphisms in MS risk.

Aging and Neuroinflammatory Disorders: New Biomarkers and Therapeutic Targets

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Chronic neuroinflammation is a common feature of the pathogenic mechanisms involved in various neurodegenerative age-associated disorders, such as Alzheimer's disease, multiple sclerosis, Parkinson’s disease, and dementia.

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In particular, persistent low-grade inflammation may disrupt the brain endothelial barrier and cause a significant increase of pro-inflammatory cytokines and immune cells into the cerebral tissue that, in turn, leads to microglia dysfunction and loss of neuroprotective properties.

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Nowadays, growing evidence highlights a strong association between persistent peripheral inflammation, as well as metabolic alterations, and neurodegenerative disorder susceptibility. The identification of common pathways involved in the development of these diseases, which modulate the signalling and immune response, is an important goal of ongoing research.

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The aim of this review is to elucidate which inflammation-related molecules are robustly associated with the risk of neurodegenerative diseases. Of note, peripheral biomarkers may represent direct measures of pathophysiologic processes common of aging and neuroinflammatory processes. In addition, molecular changes associated with the neurodegenerative process might be present many decades before the disease onset. Therefore, the identification of a comprehensive markers panel, closely related to neuroinflammation, could be helpful for the early diagnosis, and the identification of therapeutic targets to counteract the underlying chronic inflammatory processes.

Non-Skeletal Activities of Vitamin D: From Physiology to Brain Pathology

Vitamin D is a secosteroid hormone regulating the expression of almost 900 genes, and it is involved in the regulation of calcium and phosphate metabolism, immune response, and brain development. Low blood vitamin D levels have been reported in patients affected by various diseases. Despite a large amount of literature data, there is uncertainty surrounding the role of vitamin D as a serum biomarker in Alzheimer’s disease (AD) and Parkinson’s disease (PD). Indeed, the lack of internationally recognized 25(OH)D₃ reference measurement procedures and standard materials in the past led to unstandardized serum total 25(OH)D₃ results among research and clinical care laboratories. Thus, most of the literature studies reported unstandardized data, which are of little use and make it difficult to draw conclusions of the role of vitamin D in AD and PD. This review summarizes the extra-skeletal actions of vitamin D, focusing its role in immunomodulation and brain function, and reports the issue of lacking standardized literature data concerning the usefulness of vitamin D as a biomarker in AD and PD.

Cerebrospinal Fluid Analysis in Multiple Sclerosis Diagnosis: An Update

Multiple sclerosis (MS) is an immune-mediated demyelinating disease of the central nervous system (CNS) with brain neurodegeneration. MS patients present heterogeneous clinical manifestations in which both genetic and environmental factors are involved. The diagnosis is very complex due to the high heterogeneity of the pathophysiology of the disease. The diagnostic criteria have been modified several times over the years. Basically, they include clinical symptoms, presence of typical lesions detected by magnetic resonance imaging (MRI), and laboratory findings. The analysis of cerebrospinal fluid (CSF) allows an evaluation of inflammatory processes circumscribed to the CNS and reflects changes in the immunological pattern due to the progression of the pathology, being fundamental in the diagnosis and monitoring of MS. The detection of the oligoclonal bands (OCBs) in both CSF and serum is recognized as the “gold standard” for laboratory diagnosis of MS, though presents analytical limitations. Indeed, current protocols for OCBs assay are time-consuming and require an operator-dependent interpretation. In recent years, the quantification of free light chain (FLC) in CSF has emerged to assist clinicians in the diagnosis of MS. This article reviews the current knowledge on CSF biomarkers used in the diagnosis of MS, in particular on the validated assays and on the alternative biomarkers of intrathecal synthesis.

Vitamin D and the nervous system

Objective: to summarise the activities that Vitamin D (VD) carries out in the brain and to clarify the potential role of VD in neurological diseases. Methods: a literature research has been performed in Pubmed using the following keywords: 'Vitamin D', 'nervous system', 'brain'. Results: the studies reviewed show that VD contributes to cerebral activity in both embryonic and adult brain, helping the connectivity of neural circuits responsible for locomotor, emotional and reward-dependent behavior. Low VD serum levels have been found in patients affected by Alzheimer Disease, Parkinson Disease, Multiple Sclerosis, Autism Spectrum Disorders, Sleep Disorders and Schizophrenia. Discussion: findings are controversial and should be interpreted with caution, since most of the studies performed have observational study set and few interventional studies are available, producing conflicting results. Overall, it can be stated that the potential role of Vitamin D in neurological diseases is mostly unclear and further randomised controlled trials are needed to understand better whether Vitamin D supplementation treatment can be useful in brain disorders.

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.

Fibroblast Growth Factor 23 to Alpha-Klotho Index Correlates with Systemic Sclerosis Activity: A Proposal for Novel Disease Activity Marker

Systemic sclerosis, a connective tissue disease, is characterized by thickening of the skin, massive fibrosis of internal organs, vasculopathy, and immune system functioning aberration. Recently, vitamin D (VD) deficit, seen almost universally in patients with systemic sclerosis (SSc), has gained much attention. VD metabolism is precisely orchestrated at the level of the kidney by regulators: parathyroid hormone (PTH) and fibroblast growth factor 23 (FGF23) and their receptors with a FGF23 co-receptor—α-Klotho. The aim of this study was to assess the levels of VD, α-Klotho, FGF23 in SSc patients and to find the relationship between those parameters and disease activity. We enrolled 48 SSc patients with a diffuse variant of SSc and 23 sex- and age-matched healthy volunteers that served as the control group (CG). Patients were characterized by lower level of VD in comparison to CG (19.8 (12.6–28.9) vs. 24.5 (21.3–31.5) ng/mL; p < 0.01), significantly reduced levels of iFGF23 (19.3 (12.1–30.5) vs. 73.9 (59.7–110.2) pg/mL p < 0.001), and similar α-Klotho concentrations (1415 ± 557 vs. 1526 ± 397 pg/mL), respective. None of these parameters correlated with the extent of skin involvement (modified Rodnan Skin Score) and disease activity according to Eustar 2017 guidelines. The FGF23/α-Klotho index was significantly reduced in SSc patients (0.013 (0.0081–0.025) vs. 0.055 (0.038–0.095); p < 0.001), and its log₁₀ correlated (r = 0.35; p < 0.001) with disease activity score (Eular2017). Our data showed that the FGF23/α-Klotho index may be considered as a novel, potential marker of systemic sclerosis activity.

The immunological implication of the new vitamin D metabolism

Vitamin D is a neuro-hormone regulating calcium-phosphate homeostasis, cell proliferation, and immunomodulation. Exogenous and endogenous vitamin D is inactive, and two hydroxylations are required to produce the active hormone. The first hydroxylation is unique to the liver, while the second step occurs in kidney, brain, lung, prostate, placenta, and immune cells. Kidney-derived calcitriol regulates calcium homeostasis. Active hormone produced by brain and immune cells mediates immune system response; lung calcitriol is involved in fighting respiratory tract infections; finally, prostate and placenta vitamin D regulates cells growth and proliferation within such tissues. Immune modulation by vitamin D includes enhancing innate immune response, attenuating and stimulating Th1 and Th2 cell proliferation, respectively, and promoting self-tolerance. Hypovitaminosis D is a common finding in several autoimmune diseases. It is unclear whether hypovitaminosis D could be a consequence or a cause of autoimmune diseases and whether vitamin D supplementation has an impact on these patients. Moreover, there is no consensus on oral cholecalciferol dosage for supplementation. More interventional studies are required to better define how vitamin D could represent both a causation agent in autoimmunity and a target for therapeutic strategies in autoimmune patients.

CYP27A1, CYP24A1, and RXR-α Polymorphisms, Vitamin D, and Multiple Sclerosis: a Pilot Study

Multiple sclerosis (MS) is a neurodegenerative autoimmune disease resulting from a complex interaction of genetic and environmental factors. Hypovitaminosis D seems to contribute to MS susceptibility as both an environmental and a genetic risk factor. The aim of our study was to investigate the association of SNPs in CYP27A1, CYP24A1, and RXR- α genes, vitamin D status, and MS risk. We performed a nested case-control study on patients with multiple sclerosis and healthy controls. Serum 25(OH)D₃ levels and genotyping of CYP27A1, CYP24A1, and RXR-α -SNPs were investigated both in MS patients and in healthy controls. Serum 25(OH)D₃ levels were measured by a high-performance liquid chromatography (HPLC). Molecular analysis was performed by real-time PCR. The distribution of genotypic and allelic frequencies was not significantly different between patients and controls, except for rs2248137 CYP24A1. In particular, CC genotype (C minor allele) showed a higher frequency in MS patients in comparison to healthy controls. Moreover, we observed significantly lower serum 25(OH)D3 levels in MS patients with CC genotype in comparison to MS patients with GG and GC genotype. The findings of our study suggest a role of rs2248137 CYP24A1 in multiple sclerosis risk.

Vitamin D levels in systemic sclerosis patients: a meta-analysis

PURPOSE

This study aimed to investigate the association between vitamin D and systemic sclerosis (SSc) by meta-analysis.

METHODS

A comprehensive search was performed through June 12, 2017. Pooled standardized mean difference (SMD) was used to estimate the mean vitamin D difference between case and control groups (or between diffused- and limited-type SSc). Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were used to assess the impact of vitamin D level on clinical characteristics of SSc patients. All statistical analyses were performed using Revman 5.0 software.

RESULTS

The search yielded six studies with a total of 554 SSc patients and 321 healthy controls. The meta-analysis showed that SSc patients suffered from decreased vitamin D levels (SMD =-8.72 ng/mL; 95% CI: -10.11 to -7.32) compared with healthy controls. The meta-analysis results of three studies with 240 SSc patients (93 diffused-type and 147 limited-type SSc patients) showed that diffused-type SSc patients exhibited lower vitamin D levels (SMD =-4.71 ng/mL; 95% CI: -8.98 to -0.44) compared with limited-type SSc patients. However, vitamin D level was not found to be associated with Rodnan score (SMD =-2.29 ng/mL, 95% CI: -8.49 to 3.91, P=0.47), systolic pulmonary pressure (SMD =-1.68 ng/mL, 95% CI: -10.79 to 7.43, P=0.72), gastrointestinal ulcer (RR =1.01, 95% CI: 0.53-1.93, P=0.98), or pulmonary involvement (RR =1.01, 95% CI: 0.36-2.86, P=0.99) in SSc patients.

CONCLUSION

SSc patients exhibited lower vitamin D levels compared with healthy controls. Vitamin D levels in diffused-type SSc patients were significantly lower than those in limited-type SSc patients. The severity of clinical features was not associated with the extent of vitamin D deficit. Therefore, we hypothesize that SSc patients, especially diffused type, have lower vitamin D levels, and that the decrease of vitamin D levels might not be an accelerating factor of SSc severity.

Association of CYP2R1 rs10766197 with MS risk and disease progression

BACKGROUND

MS is a neurodegenerative autoimmune disease resulting from a complex interaction of genetic and environmental factors. Among these, vitamin D and genetic variants associated with vitamin D-metabolism gain great attention. The aim of our study was to assess five SNPs in NADSYN1 and CYP2R1 genes in relation to serum 25-OH-vitamin D3 levels in MS patients and controls.

METHODS

25-OH-vitamin D3 levels and genotyping of CYP2R1- and NADSYN1-SNPs were investigated both in MS patients and in healthy controls.

RESULTS

The analysis revealed lower 25-OH-vitamin D3 concentrations in MS patients than in controls and an association of rs10766197 CYP2R1 SNP with MS risk. After stratifying MS patients according to gender, we found that the minor allele A of rs10766197 had a higher frequency in men in comparison to women affected by MS. Additionally, the presence of allele A in men was associated with disease progression, assessed by EDSS and MSSS scores.

CONCLUSION

The findings of our study open new perspectives for a role of CYP2R1 in both risk and progression of MS, with sex-related differences.