Vitamin D in systemic and organ-specific autoimmune diseases

Mathematical Analysis of an Autoimmune Diseases Model: Kinetic Approach

A new mathematical model of a general autoimmune disease is presented. Basic information about autoimmune diseases is given and illustrated with examples. The model is developed by using ideas from the kinetic theory describing individuals expressing certain functions. The modeled problem is formulated by ordinary and partial equations involving a variable for a functional state. Numerical results are presented and discussed from a medical view point.

Antitumor effects and mechanisms of 1,25(OH)2D3 in the Pfeiffer diffuse large B lymphoma cell line

Diffuse large B cell lymphoma (DLBCL) represents the most common subtype of non-Hodgkin lymphoma in China. 1,25-Dihydroxyvitamin D₃ [1,25(OH)₂D₃] has been shown to possess significant antitumor potential and is degraded by 25-hydroxyvitamin D-24-hydroxylase (CYP24A1). In the present study, the role of CYP24A1 and autophagy, and their underlying mechanisms in the anticancer effects of 1,25(OH)₂D₃ in DLBCL cells, were investigated. It was found that the levels of CYP24A1 in DLBCL lymph node tissues were higher than in hyperplasia lymphadenitis tissue. Moreover, the expression of CYP24A1 was positively associated with the Ann Arbor stage and the International Prognostic Index in patients with DLBCL, and negatively associated with the clinical response to treatment. Patients >60 years of age were found to have a higher level of CYP24A1. 1,25(OH)₂D₃ inhibited the proliferation of the Pfeiffer DLBCL cell line and increased the G1 phase population of Pfeiffer cells. Rapamycin (RAPA) in combination with 1,25(OH)₂D₃ increased the G1 phase distribution of Pfeiffer cells. Furthermore, RAPA blocked the increase of CYP24A1 and vitamin D receptor (VDR) expression induced by 1,25(OH)₂D₃. 1,25(OH)₂D₃ induced the formation of autophagosomes, increased the expression of autophagy related protein light chain (LC)3II/LC3I and reduced the expression of the ubiquitin binding protein P62. In addition, 1,25(OH)₂D₃ decreased the phosphorylation of AKT and mammalian target of RAPA (mTOR), and downstream targets eukaryotic translation imitation factor 4E-binding protein 1 and ribosomal protein S6 kinase β-1 in Pfeiffer cells. The results from the present study suggested that CYP24A1 may be a novel prognostic indicator for DLBCL. 1,25(OH)₂D₃ inhibited proliferation and induced autophagy of Pfeiffer cells. In addition, 1,25(OH)₂D₃ increased the G1 phase population of Pfeiffer cells. These effects may be mediated by inhibition of the AKT/mTOR/PI3K signaling pathway. RAPA increased the cell cycle arrest induced by 1,25(OH)₂D₃ by blocking the upregulated expression of CYP24A1 and VDR.

The effect of vitamin D on thyroid autoimmunity in euthyroid men with autoimmune thyroiditis and testosterone deficiency

BACKGROUND

Autoimmune (Hashimoto's thyroiditis) is characterized by a strong female preponderance, which may suggest that sex hormones have an impact on thyroid autoimmunity. The aim of this study was to investigate whether testosterone determines vitamin D action on thyroid antibody titers and thyroid function tests in men with autoimmune thyroiditis and low testosterone levels.

METHODS

The study included 36 men with testosterone deficiency, 17 of whom had been treated for at least 26 weeks with oral testosterone undecanoate (120 mg daily). Because of coexistent euthyroid Hashimoto's thyroiditis, all participants were then treated with vitamin D (100 μg daily). Serum titers of thyroid peroxidase and thyroglobulin antibodies, serum levels of thyrotropin, free thyroid hormones, testosterone and 25-hydroxyvitamin D, as well as Jostel's thyrotropin index, SPINA-GT and SPINA-GD were assessed before vitamin D treatment and 26 weeks later.

RESULTS

With the exception of testosterone levels, there were no significant differences between both study groups in serum hormone levels, antibody titers and thyroid function tests. All participants completed the study. In addition to increasing 25-hydroxyvitamin D levels, vitamin D increased SPINA-GT and reduced thyroid peroxidase and thyroglobulin antibody titers. In testosterone-treated men, vitamin D increased testosterone levels. Vitamin D did not affect serum levels of thyrotropin, free thyroid hormones, Jostel's thyrotropin index and SPINA-GD. Treatment-induced changes in thyroid antibody titers and SPINA-GT were more pronounced in testosterone-treated than testosterone-naïve men.

CONCLUSIONS

The obtained results suggest that the beneficial effect on thyroid autoimmunity and thyroid secretory function is stronger in men receiving testosterone therapy.

Gender Differences in Vitamin D Status in China

Background

Vitamin D insufficiency is widespread in China. Various factors influence vitamin D level in the body. The present study investigated vitamin D status of residents in Jinzhong city, China, and analyzed the influence of gender on vitamin D status.

Material/Methods

In this cross-sectional study, 302 participants (176 men and 126 women) were recruited. Anthropometric data (body circumferences and height, weight) were collected, and serum vitamin D concentration was tested.

Results

Inadequate levels of vitamin D were found in 69% of men and 75% of women. Women’s 25(OH)D level (38.40±12.37 nmol/l) was substantially lower than that of the men (43.49±14.78 nmol/l) (p<0.01). The young women group had the lowest vitamin D level, which was even significantly below that of the elderly women group. Multiple linear regression analysis showed gender was significantly associated with vitamin D status (p<0.01).

Conclusions

Vitamin D deficiency is common in residents of Jinzhong during the winter. Compared to men, women are more prone to have inadequate vitamin D levels.

The Association between Low Vitamin D Status and Autoimmune Thyroid Disease in Korean Premenopausal Women: The 6th Korea National Health and Nutrition Examination Survey, 2013-2014

BACKGROUND

This study aimed to analyze the association of low vitamin D status with thyroid autoimmunity and dysfunction in the Korean population according to sex and menopausal status in women.

METHODS

This study was based on the data acquired from the 6th Korea National Health and Nutrition Examination Survey. We enrolled 4,356 subjects who had data of thyroid function, antithyroid peroxidase antibody (TPOAb), and serum 25-hydroxyvitamin D (25[OH]D) levels. We excluded subjects who were pregnant and who had a history of thyroid disease or thyroid cancer, and those with transient thyroid dysfunction who tested negative for TPOAb (TPOAb[-]).

RESULTS

TPOAb positivity (TPOAb[+]) with thyroid dysfunction (subclinical and overt hypothyroidism) was more prevalent in the vitamin D deficient group than in the vitamin D insufficient and sufficient groups including premenopausal (P=0.046) and postmenopausal women (P=0.032), although no significant differences were observed in men. The mean serum 25(OH)D level was significantly lower in the TPOAb(+) with thyroid dysfunction group than in the TPOAb(+) with euthyroidism and TPOAb(-) groups of premenopausal women (P=0.001), although no significant differences were observed in men and postmenopausal women. Multivariate binary logistic regression analysis, adjusted for age, body mass index, and current smoking status, showed that vitamin D insufficiency and deficiency were significantly associated with TPOAb(+) with thyroid dysfunction in premenopausal women (P<0.001), although no significant associations were observed in men and postmenopausal women.

CONCLUSION

Low vitamin D status was significantly associated with thyroid autoimmunity and dysfunction in the Korean population, especially in premenopausal women.

Study of Vitamin D Level and Vitamin D Receptor Polymorphism in Hypothyroid Egyptian Patients

Purpose

The current study aimed at assessing vitamin D level and vitamin D receptor polymorphism in hypothyroid Egyptian patients and its effect on hypothyroidism and thyroid morphology, also to find a causal relation between vitamin D and hypothyroidism.

Methods

This case-control study was conducted on 35 hypothyroid patients and 35 matched unrelated healthy controls. Total serum 25-hydroxyvitamin D3 and thyroid antibodies were measured using a human ELISA kit. Genotyping was performed by using real-time PCR. HOMA-IR was also calculated (fasting insulin in mIU/L × fasting glucose in mg/dL/405). All subjects were assessed for thyroid morphology by thyroid ultrasonography.

Results

Vitamin D level was lower in hypothyroid patients than in control subjects. Vitamin D was also inversely related to TSH, HOMA-IR, and levels of anti-TG and anti-TPO. VDR polymorphism (Fok1 and Apa1) had no relation to TSH or vitamin D levels in both patients and control groups. Low vitamin D levels were associated with increased thyroid vascularity and nodularity; furthermore, vitamin D was inversely proportional to thyroid gland volume. Correlation of HOMA-IR with the levels of both anti-TG and anti-TPO in the 70 subjects proved that HOMA-IR was positively correlated to both antibodies.

Conclusion

This study confirmed the association of vitamin D deficiency with hypothyroidism, thyroid autoimmunity, increased volume, nodularity, and vascularity of thyroid gland in hypothyroid patients as well as increased HOMA-IR. It proved the association between HOMA-IR and thyroid autoimmunity. The study proved no association between VDR polymorphisms (Fok1 and Apa1) with either vitamin D levels or TSH levels.

Causal Link Between Vitamin D and Total Testosterone in Men: A Mendelian Randomization Analysis

CONTEXT

Low circulating vitamin D levels have been associated with lower total testosterone levels. These epidemiological associations, if true, would have public health importance because vitamin D deficiency is common and correctable. We tested whether genetically lowered vitamin D levels were associated with lower total testosterone (T), using Mendelian randomization (MR) methodology.

DESIGN AND SETTING

A total of 4254 men were enrolled from the Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China) study, which was performed at 23 sites in eastern China during 2014 to 2016. Using four single-nucleotide polymorphisms strongly associated with 25-hydroxyvitamin D [25(OH)D] levels, we created a genetic risk score (GRS) as an instrumental variable to estimate the effect of genetically lowered 25(OH)D on total T.

MAIN OUTCOME MEASURE

Total T was detected by chemiluminescence assay.

RESULTS

Lower 25(OH)D levels were associated with lower total T (β, 0.40; 95% CI, 0.23 to 0.58) after multivariable adjustment. Per-SD increase in the vitamin D GRS (VD_GRS) was significantly associated with 25(OH)D (β, -1.64; 95% CI, -2.04 to -1.24) and with total T (β, -0.19; 95% CI, -0.37 to -0.02). Using VD_GRS as the instrumental variable in the MR analysis, the causal regression coefficient of genetically determined per-SD increase for 25(OH)D on total T was 0.12 (95% CI, 0.02 to 0.22).

CONCLUSION

We provide evidence for the biologically plausible causal effects of 25(OH)D on total T using MR analysis. Whether vitamin D supplementation can raise androgen levels merits further investigation in long-term, randomized controlled trials.

Vitamin D in trichology: a comprehensive review of the role of vitamin D and its receptor in hair and scalp disorders

Vitamin D plays an important role in maintaining the homeostasis of various biological systems. Beside its well-known function in calcium and phosphate metabolism, it plays a major role in pathophysiology of skin and adnexa. Indeed, vitamin D, through its receptor (VDR), decreases keratinocyte proliferation, improves their differentiation and modulates both cutaneous innate (antimicrobial activity and antigen presentation) and adaptative immunity (T and B lymphocyte function). The maintenance of normal hair is dependant on the integrity of the dermis, epidermis and hair cycles. Beside its effect on epidermal differentiation, VDR plays a vital role in preserving the hair follicle integrity. While the relevance of VDR has been fully elucidated, the real value of vitamin D in the hair follicle cycle still remains uncertain. To date, results in literature remain contradicting and far from definitive; still, the role of vitamin D in the various forms of human alopecia is likely to be significant. The aim of this article is to review evidence about the role of vitamin D and its receptor in trichology, with a focus on scarring and non-scarring alopecia and in particular on the potential therapeutic use of Vitamin D for hair and scalp disorders.

Impact of red meat, processed meat and fibre intake on risk of late-onset chronic inflammatory diseases: prospective cohort study on lifestyle factors using the Danish 'Diet, Cancer and Health' cohort (PROCID-DCH): protocol

INTRODUCTION

Chronic inflammatory diseases (CIDs) (Crohn's disease, ulcerative colitis, psoriasis, psoriatic arthritis, rheumatoid arthritis and multiple sclerosis) are diseases of the immune system that have some shared genetic and environmental predisposing factors, but still few studies have investigated the effects of lifestyle on disease risk of several CIDs. The primary aim of this prospective cohort study is to investigate the impact of fibre, red meat and processed meat on risk of late-onset CID, with the perspective that results of this study can contribute in supporting future diet recommendations for effective personalised prevention.

METHODS AND ANALYSIS

The study will use data from 57 053 persons from the prospective Danish cohort study 'Diet, Cancer and Health' together with National Health Registry data. The follow-up period is from December 1993 to December 2018. Questionnaire data on diet and lifestyle were collected at entry to the Diet, Cancer and Health study. The outcome CID is defined as having a diagnosis of one of the CIDs registered in the National Patient Registry or, for multiple sclerosis, in the Danish Multiple Sclerosis Registry during follow-up and being treated with a drug used for the specific disease. The major outcome of the analyses will be to detect variability in risk of late onset of any CID and, if power allows, disease risk of late onset of each CID diagnosis between persons with different fibre and red meat, and processed meat intake. The outcome will be adjusted for age, sex, body mass index, physical activity, energy, alcohol, fermented dairy products, education, smoking status, hormone replacement therapy and comorbidity.

ETHICS AND DISSEMINATION

The study is approved by the Danish Data Protection Agency (2012-58-0018). The core study is an open register-based cohort study. The study does not need approval from the Ethics committee or Institutional Review Board by Danish law. Study findings will be disseminated through peer-reviewed journals, patient associations and presentations at international conferences.

TRIAL REGISTRATION NUMBER

NCT03456206; Post-results.

Vitamin D deficiency in northern Taiwan: a community-based cohort study

Background

Vitamin D deficiency has become an important public health problem, however few studies have been conducted in subtropical countries, and the predictors of vitamin D deficiency in people with healthy renal function are unclear. The objective of this study was to evaluate the prevalence and factors associated with vitamin D deficiency in northern Taiwan.

Methods

The cross-sectional study was performed between August 2013 and August 2017, and included 3954 participants without chronic kidney disease (CKD) aged ≥30 years in northern Taiwan. Serum 25-hydroxyvitamin D [25(OH)-D] levels, biochemistry, sociodemographic variables (age, sex, education, occupation) and lifestyle habits (tea, coffee consumption and physical activities) were recorded. Associations between vitamin D status and these variables were examined using a regression model. The definition of deficiency was defined as a serum 25(OH)-D level < 20 ng/mL (50 nmol/L).

Results

The mean 25(OH)-D concentration was 28.9 ng/mL, and 22.4% of the study population had vitamin D deficiency. There was a significantly higher vitamin D deficiency ratio in the women compared to the men (22.9% vs 9.9%, p < 0.001). Vitamin D deficiency was most prevalent (38.4%) in those aged 30–39 years. Those with a graduate degree had the highest rate of vitamin D deficiency (31.5%). The predictors of vitamin D deficiency included female sex, young age, high education level, living in an urban area and physical inactivity. Tea consumption was negatively associated with vitamin D deficiency.

Conclusions

Vitamin D deficiency is prevalent in subtropical areas such as northern Taiwan in healthy individuals without CKD.

Immunological effects of vitamin D and their relations to autoimmunity

Vitamin D deficiency is an established risk factor for many autoimmune diseases and the anti-inflammatory properties of vitamin D underscore its potential therapeutic value for these diseases. However, results of vitamin D3 supplementation clinical trials have been varied. To understand the clinical heterogeneity, we reviewed the pre-clinical data on vitamin D activity in four common autoimmune diseases: multiple sclerosis (MS), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), and inflammatory bowel disease (IBD), in which patients are commonly maintained on oral vitamin D3 supplementation. In contrast, many pre-clinical studies utilize other methods of manipulation (i.e. genetic, injection). Given the many actions of vitamin D3 and data supporting a vitamin D-independent role of the Vitamin D receptor (VDR), a more detailed mechanistic understanding of vitamin D3 activity is needed to properly translate pre-clinical findings into the clinic. Therefore, we assessed studies based on route of vitamin D3 administration, and identified where discrepancies in results exist and where more research is needed to establish the benefit of vitamin D supplementation.

Altered morpho-functional features of bones in autoimmune disease-prone BXSB/MpJ- Yaa mice

IMPACT STATEMENT

Bone disease, such as osteoporosis and rheumatoid arthritis, increases because of the progression of an aging society. Autoimmune disease are important and predisposing factors for the pathogenesis of the bone disease; however, the pathological mechanism is unclear. We have demonstrated that systemic autoimmune disease in BXSB/MpJ- Yaa is closely associated with the morpho-functional abnormalities of bones including bone marrow and has complicated pathology. The abnormalities are characterized by altered regulations of serum calcium, anemia tendency, and hematopoiesis with increased WBCs and decreased PLs, short length and low mass of long bones, imbalance in the populations of osteoclasts and osteoblasts, and increased expression of candidate genes for causing and/or exacerbating their phenotypes. Therefore, BXSB/MpJ- Yaa serves as a model to elucidate bone phenotypes in systemic autoimmune disease that would be affected by the factors in the bone as well as the other immune and/or mineral metabolism organs both in human and experimental medicine.

Nutritional Modulation of Immune Function: Analysis of Evidence, Mechanisms, and Clinical Relevance

It is well-established that the nutritional deficiency or inadequacy can impair immune functions. Growing evidence suggests that for certain nutrients increased intake above currently recommended levels may help optimize immune functions including improving defense function and thus resistance to infection, while maintaining tolerance. This review will examine the data representing the research on prominent intervention agents n-3 polyunsaturated fatty acids (PUFA), micronutrients (zinc, vitamins D and E), and functional foods including probiotics and tea components for their immunological effects, working mechanisms, and clinical relevance. Many of these nutritive and non-nutritive food components are related in their functions to maintain or improve immune function including inhibition of pro-inflammatory mediators, promotion of anti-inflammatory functions, modulation of cell-mediated immunity, alteration of antigen-presenting cell functions, and communication between the innate and adaptive immune systems. Both animal and human studies present promising findings suggesting a clinical benefit of vitamin D, n-3 PUFA, and green tea catechin EGCG in autoimmune and inflammatory disorders, and vitamin D, vitamin E, zinc, and probiotics in reduction of infection. However, many studies report divergent and discrepant results/conclusions due to various factors. Chief among them, and thus call for attention, includes more standardized trial designs, better characterized populations, greater consideration for the intervention doses used, and more meaningful outcome measurements chosen.

The relationship between hypertriglyceridemic-waist phenotype and vitamin D status in type 2 diabetes

Background: The aim of the study was to explore the relationship between hypertriglyceridemic-waist (HTW) phenotype and vitamin D status in type 2 diabetes. Methods: A cross-sectional study was conducted in subjects with type 2 diabetes. This study enrolled 338 type 2 diabetic (190 males and 148 females). The HTW phenotype was defined as serum triglyceride concentrations ≥1.7 mmol/L and waist circumference ≥90 cm (male) and 85 cm (female). Multiple logistic regression models were used for modeling relationships between HTW phenotype and vitamin D status. Results: The prevalence of HTW phenotype was 36.4%. The prevalence of HTW phenotype was 10.5%, 27.2%, and 41.6% in type 2 diabetes with vitamin D sufficiency, vitamin D insufficiency, and vitamin D deficiency, respectively. In multiple logistic regression analysis, subjects with vitamin D deficiency were more likely to have HTW phenotype (OR=6.222, 95%CI: 1.307-29.620, P=0.022) compared with subjects with vitamin D sufficiency. Conclusions: There was a significant correlation between HTW phenotype and vitamin D status in type 2 diabetes.

To Supplement or not to Supplement? The Rationale of Vitamin D Supplementation in Systemic Lupus Erythematosus

Background:

Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disease characterised by abnormal activation of the immune system, chronic inflammation and organ damage. Lupus patients are more prone to be vitamin D deficient. However, current evidence is not conclusive with regards to the role played by vitamin D in SLE development, progression, and clinical manifestations.

Objective:

Here, we will summarise the current knowledge about vitamin D deficiency prevalence, risk factors, molecular effects, and potential pathogenic role in SLE. We will focus on the link between vitamin D deficiency and lupus clinical manifestations, and on the clinical trials assessing the effects of vitamin D supplementation in SLE.

Method:

A detailed literature search was performed exploiting the available databases, using “vitamin D and lupus/SLE” as keywords. The relevant interventional trials published over the last decade have been considered and the results are reported here.

Conclusion:

Several immune cells express vitamin D receptors. Thus, an immunomodulatory role for vitamin D in lupus is plausible. Numerous observational studies have investigated the relationship between vitamin D levels and clinical/serological manifestations of SLE with contrasting results. Negative correlations between vitamin D levels and disease activity, fatigue, renal and cardiovascular disease, and anti-dsDNA titres have been described but not conclusively accepted. In experimental models of lupus, vitamin D supplementation can improve the disease. Interventional trials have assessed the potential therapeutic value of vitamin D in SLE, but further larger studies are needed.

Vitamin D levels in patients with recurrent aphthous stomatitis

Background

Lower serum vitamin D levels, a major public health problem worldwide, has been found to be associated with various infectious diseases, cancers, autoimmune and dermatological diseases. The serum levels of vitamin D in patients with recurrent aphthous stomatitis are not clear. We investigated the vitamin D levels in patients with recurrent aphthous stomatitis.

Methods

Forty patients with recurrent aphthous stomatitis (Group I) and 70 healthy controls (Group II) included in the study. The characteristics of aphthous lesions (duration of disease and remission, frequency, diameter and number of the lesions) and demographics of the participants were recorded. Serum 25-hydroxycholecalciferol levels were measured using electrochemiluminescence binding method.

Results

There was no statistically significant difference between the groups in terms of age (p = 0.06) and sex (p = 0.4). Other baseline characteristics were not significantly different between the groups (p > 0.05 for all). The mean diameter of aphthous lesions was 0.5 (0.4–0.6) cm and the mean number of lesions was 2.2 ± 1.5. Serum vitamin D levels were 11 ± 7.04 ng/ml in Group I and 16.4 ± 10.19 ng/ml in Group II. Serum vitamin D levels were significantly lower in patients with recurrent aphthous stomatitis (p = 0.004).

Conclusions

The present study showed lower vitamin D levels in patients with recurrent aphthous stomatitis compared to healthy controls.

Biochemical Characterization of the Cytochrome P450 CYP107CB2 from Bacillus lehensis G1

The bioconversion of vitamin D3 catalyzed by cytochrome P450 (CYP) requires 25-hydroxylation and subsequent 1α-hydroxylation to produce the hormonal activated 1α,25-dihydroxyvitamin D3. Vitamin D3 25-hydroxylase catalyses the first step in the vitamin D3 biosynthetic pathway, essential in the de novo activation of vitamin D3. A CYP known as CYP107CB2 has been identified as a novel vitamin D hydroxylase in Bacillus lehensis G1. In order to deepen the understanding of this bacterial origin CYP107CB2, its detailed biological functions as well as biochemical characteristics were defined. CYP107CB2 was characterized through the absorption spectral analysis and accordingly, the enzyme was assayed for vitamin D3 hydroxylation activity. CYP-ligand characterization and catalysis optimization were conducted to increase the turnover of hydroxylated products in an NADPH-regenerating system. Results revealed that the over-expressed CYP107CB2 protein was dominantly cytosolic and the purified fraction showed a protein band at approximately 62 kDa on SDS-PAGE, indicative of CYP107CB2. Spectral analysis indicated that CYP107CB2 protein was properly folded and it was in the active form to catalyze vitamin D3 reaction at C25. HPLC and MS analysis from a reconstituted enzymatic reaction confirmed the hydroxylated products were 25-hydroxyitamin D3 and 1α,25-dihydroxyvitamin D3 when the substrates vitamin D3 and 1α-hydroxyvitamin D3 were used. Biochemical characterization shows that CYP107CB2 performed hydroxylation activity at 25 °C in pH 8 and successfully increased the production of 1α,25-dihydroxyvitamin D3 up to four fold. These findings show that CYP107CB2 has a biologically relevant vitamin D3 25-hydroxylase activity and further suggest the contribution of CYP family to the metabolism of vitamin D3.

The Effects of Vitamin D Supplementation on Thyroid Function in Hypothyroid Patients: A Randomized, Double-blind, Placebo-controlled Trial

BACKGROUND

Data on the effects of vitamin D supplementation on thyroid function in hypothyroid patients are scarce.

OBJECTIVE

This study was done to evaluate the effects of vitamin D supplementation on thyroid function in hypothyroid patients.

MATERIAL AND METHODS

This randomized double-blind, placebo-controlled trial was conducted on 201 hypothyroid patients aged 20-60 years old. Subjects were randomly assigned into two groups to intake either 50,000 IU vitamin D supplements (n = 102) or placebo (n = 99) weekly for 12 weeks. Markers of related with thyroid function were assessed at first and 12 weeks after the intervention.

RESULTS

After 12 weeks of intervention, compared to the placebo, vitamin D supplementation resulted in significant increases in serum 25-hydroxyvitamin D (+26.5 ± 11.6 vs. 0.0 ± 0.0 ng/mL, P < 0.001) and calcium (+0.4 ± 0.7 vs. 0.1 ± 0.6 mg/dL, P = 0.002), and a significant decrease in serum thyroid-stimulating hormone (TSH) levels (-0.4 ± 0.6 vs. +0.1 ± 2.0 μIU/mL, P = 0.02). A trend towards a greater decrease in serum parathyroid hormone (PTH) levels was observed in vitamin D group compared to placebo group (-3.8 vs. +1.9, P = 0.07). We did not observe any significant changes in serum T3, T4, alkaline phosphatase (ALP) and albumin levels following supplementation of vitamin D compared with the placebo.

CONCLUSION

Overall, the current study demonstrated that vitamin D supplementation among hypothyroid patients for 12 weeks improved serum TSH and calcium concentrations compared with the placebo, but it did not alter serum T3, T4, ALP, PTH, and albumin levels.

Vitamin D in acutely ill patients

Objective To investigate 25(OH)D₃ levels and their relationship to survival in a cohort of acutely ill patients on admission to an intensive care unit. Methods This study enrolled acutely ill patients at admission to an intensive care unit and a group of sex- and age-matched healthy control subjects. The 25(OH)D₃ levels were measured using an enzyme immunoassay. C-reactive protein and procalcitonin levels were also measured using immunoassays. Results A total of 50 acutely ill patients and 50 healthy control subjects were enrolled in the study. The mean ± SEM 25(OH)D₃ levels were significantly lower in the acutely ill patients compared with the control group (11.74 ± 0.88 ng/ml versus 24.66 ± 1.60 ng/ml, respectively). The 25(OH)D₃ levels were not related to survival. An inverse relationship was observed between 25(OH)D₃ levels and C-reactive protein levels. A weak inverse relationship was also observed between 25(OH)D₃ levels and procalcitonin levels. Conclusions The 25(OH)D₃ levels were decreased in acutely ill patients admitted to an intensive care unit compared with healthy control subjects. 25(OH)D₃ levels may be inversely related to C-reactive protein and procalcitonin levels.

Association between Sun Exposure, Vitamin D Intake, Serum Vitamin D Level, and Immunoglobulin G Level in Patients with Neuromyelitis Optica Spectrum Disorder

Background:

Neuromyelitis optica spectrum disorder (NMOSD) is a central nervous system inflammatory disorder in which immunoglobulin G (IgG) autoantibodies possibly play a pathogenic role against the aquaporin-4 water channel protein. Vitamin D may modulate B-cell function and decrease the IgG synthesis and may play a role in NMOSD as a crucial factor. The aim of this study was to investigate the relation between Vitamin D intakes from food, Vitamin D intake from sunlight exposure, blood Vitamin D levels, and IgG-neuromyelitis optica (NMO) level in serum of patients with NMOSD and NMO.

Method:

In this cross-sectional study, food Frequency Questionnaires (FFQ) and Sun Exposure Questionnaire (SEQ) were completed to evaluate of vitamin D intakes from food and sun light exposure. Moreover, serum levels of 25(OH) vitamin D3 and IgG-NMO were assessed in patients with NMOSD and NMO.

Results:

We assessed IgG-NMO levels in 29 patients with NMOSD that nine patients (n = 31%) were positive and for the rest it was negative. Sunlight exposure scale (P = 0.01) and 25(OH) D3 (P = 0.04) in IgG-NMO-negative patients were significantly more than patients with positive IgG-NMO. Age, gender, and latitude were not confounder variables. A positive significant correlation was observed between the sun exposure scale and serum levels of 25(OH) D3 in all participants (r = 0.747, P ≤ 0.001).

Conclusions:

Physiological variation in Vitamin D may apply a significant effect on IgG-NMO synthesis in patients with NMO. Vitamin D may have significant role in pathogenesis of NMOSD and NMO.

LC-MS/MS based 25(OH)D status in a large Southern European outpatient cohort: gender- and age-specific differences

BACKGROUND

Developed countries have a high prevalence of vitamin D deficiency. In previous studies, 25(OH)D was predominantly measured by immunoassays. The present study assessed serum 25(OH)D in a very large Southern European outpatient cohort by liquid chromatography tandem mass spectrometry (LC-MS/MS).

MATERIALS AND METHODS

74,235 serum 25(OH)D results generated under routine conditions between 2015 and 2016 were extracted from the laboratory information system of the Department of Clinical Pathology at Bolzano Hospital (Italy). In 3801 cases, parathyroid hormone (PTH) was requested in parallel. Serum 25(OH)D was measured by a NIST-972 aligned commercial LC-MS/MS method. The distribution of serum 25(OH)D concentrations in males and females of different age groups, the prevalence of 25(OH)D₂ and seasonal variability were studied.

RESULTS

The average 25(OH)D concentration in the entire cohort was 68.6 nmol/L (7.5-1880 nmol/L). Females had a 7 nmol/L higher average 25(OH)D concentration than males, which increased significantly with age. 37.9 and 28.3% of males and females, respectively, had a deficient 25(OH)D concentration of < 50 nmol/L. 620 samples (0.84%) had measureable amounts of 25(OH)D₂. In samples with a normal PTH, 25(OH)D was 11 nmol/L higher than in the entire cohort. Seasonal variation ranged between 20 and 30% and was most pronounced in young individuals. 25(OH)D₂ remained constant throughout the year.

CONCLUSION

Average serum 25(OH)D in South Tyrol is higher than in other parts of Europe. 25(OH)D and PTH show a continuous inverse relationship. Seasonal variation of serum 25(OH)D is an important aspect in young and middle-aged adults, but becomes less relevant in elderly subjects. 25(OH)D₂ is of minor practical importance in South Tyrol.

The Role of Invariant NKT in Autoimmune Liver Disease: Can Vitamin D Act as an Immunomodulator?

Natural killer T (NKT) cells are a distinct lineage of T cells which express both the T cell receptor (TCR) and natural killer (NK) cell markers. Invariant NKT (iNKT) cells bear an invariant TCR and recognize a small variety of glycolipid antigens presented by CD1d (nonclassical MHC-I). CD1d-restricted iNKT cells are regulators of immune responses and produce cytokines that may be proinflammatory (such as interferon-gamma (IFN-γ)) or anti-inflammatory (such as IL-4). iNKT cells also appear to play a role in B cell regulation and antibody production. Alpha-galactosylceramide (α-GalCer), a derivative of the marine sponge, is a potent stimulator of iNKT cells and has been proposed as a therapeutic iNKT cell activator. Invariant NKT cells have been implicated in the development and perpetuation of several autoimmune diseases such as multiple sclerosis and systemic lupus erythematosus (SLE). Animal models of SLE have shown abnormalities in iNKT cells numbers and function, and an inverse correlation between the frequency of NKT cells and IgG levels has also been observed. The role of iNKT cells in autoimmune liver disease (AiLD) has not been extensively studied. This review discusses the current data with regard to iNKT cells function in AiLD, in addition to providing an overview of iNKT cells function in other autoimmune conditions and animal models. We also discuss data regarding the immunomodulatory effects of vitamin D on iNKT cells, which may serve as a potential therapeutic target, given that deficiencies in vitamin D have been reported in various autoimmune disorders.

Vitamin D, autoimmunity and recurrent pregnancy loss: More than an association

Recurrent pregnancy loss (RPL) affects close to 1% of couples; however, the etiology is known in only about 50% of the cases. Recent studies show that autoimmune dysregulation is a probable cause of RPL, which in some cases may be overlooked. In order for a pregnancy to proceed to term, early modulation of immunologic response is required to induce tolerance to the semi-allogenic fetus. Certain subsets of both the innate and adaptive immune responses play a role in the induction of fetomaternal tolerance. A relatively predominant T-cell helper (Th) 2 and T regulatory (Treg) cell population seem to favor a better pregnancy outcome, whereas Th1 and Th17 cell populations appear to have an opposite effect. Lately, the role of vitamin D in the modulation of immune response was established. Vitamin D has been shown to promote a more favorable environment for pregnancy through various mechanisms, such as enhancement of the shift toward Th2 cells and regulation of immune cell differentiation and cytokine secretion. Therefore, it seems that vitamin D deficiency sways the balance toward a worse outcome and may play a part in recurrent pregnancy loss. This review sheds light on the immunologic changes, which occur in early pregnancy and the regulatory role vitamin D has in the maintenance of this delicate balance.

Severe electrolytes disorders with the interstitial kidney alterations in the patient with the history of total thyroidectomy and parathyroidectomy: possible role of vitamin D deficiency

Vitamin D plays vital role for the health, and its deficiency has been implicated in the diverse pathological conditions such as hypomagnesemia and abnormal immune system. Here, we present a case of severe electrolytes disorders (hypokalemia and hypomagnesemia etc.) and kidney damages associated with vitamin D deficiency.

Vitamin D and juvenile idiopathic arthritis

BACKGROUND

Vitamin D has been implicated in the pathogenesis of autoimmune diseases. While the roles of vitamin D in other autoimmune diseases have been investigated, less is known about the role of vitamin D in chronic childhood arthritis.

MAIN BODY

This review summarizes and evaluates evidence relating to 25-hydroxyvitamin D (25(OH)D) and chronic childhood arthritis. A scoping literature review was conducted using Ovid Medline, Ovid Embase, Cumulative Index to Nursing and Allied Health Literature, Web of Science and Scopus. Further, we geo-mapped the results of the studies to identify the patterns of the association between vitamin D and chronic childhood arthritis across the globe. Of 38 studies reporting 25(OH)D concentrations in childhood chronic arthritis, 32 (84.2%) reported that a significant number of children had suboptimal (< 75 nmol/L) status.

CONCLUSION

The data indicate suboptimal vitamin D status in children with chronic arthritis. Further, the association between low vitamin D and increased arthritis activity follow a north-south geographical gradient.

High fiber dietary and sodium butyrate attenuate experimental autoimmune hepatitis through regulation of immune regulatory cells and intestinal barrier

Autoimmune hepatitis (AIH) is chronic autoimmune liver disease accompanied with the imbalance of Treg/Th17 and increased intestinal permeability. We investigated the effects of a high fiber diet and sodium butyrate on the Treg/Th17 and intestinal barrier function in an experimental autoimmune hepatitis. Intraperitoneal injection of hepatic antigen (S100) was used to induce experimental autoimmune hepatitis mice model and mice were divided into normal control, S100 model control, S100 plus high fiber diet and S100 plus sodium butyrate. Serum aminotransferases and liver histology were examined. Short chain fatty acids in feces were determined by HPLC. The ratio of CD4 + C25 + Foxp3+ Treg and CD4 + IL-17 + Th17 were evaluated by flow cytometry. Tight junction proteins Zonula ocluden, Occludin and Claudin-1 were used to assess intestinal barrier function, so does Escherichia coli protein in the liver. Mice fed with either high fiber diet or sodium butyrate showed significantly lower levers of serum aminotransferases and minor liver injury compared to that of model control. Moreover, the ratio of Treg/Th17 was significantly higher in high fiber diet and sodium butyrate fed mice than that in model control. Furthermore, high fiber diet and sodium butyrate significantly increased intestinal tight junction proteins and decreased Escherichia Coli protein in the liver. In conclusion, high fiber diet and sodium butyrate can attenuate development of autoimmune hepatitis through regulation of immune regulatory cells and intestinal barrier function.

Vitamin D reduces inflammatory response in asthmatic mice through HMGB1/TLR4/NF‑κB signaling pathway

The present study aimed to investigate the effects of vitamin D (VD) on inflammatory responses in asthmatic mice and the underlying mechanism, providing a theoretical basis for clinical application of targeted drug therapy, and the development of novel drugs against asthma. Mouse models of asthma were established. Hematoxylin‑eosin staining was performed to observe the pathological changes of the lung tissue. Pulmonary function tests were conducted to determine airway resistance in asthmatic mice. ELISA was performed to measure the serum levels of inflammatory factors. Western blot analysis and reverse transcription‑quantitative polymerase chain reaction were performed to determine the changes in apoptosis‑inducing factors, and high mobility group box 1 protein (HMGB1)/Toll‑like receptor‑4 (TLR4)/nuclear factor (NF)‑κB signaling pathway‑related proteins. VD reduced infiltrated inflammatory factors, attenuated the airway resistance of asthmatic mice, decreased serum levels of interleukin (IL)‑1β, IL‑6, tumor necrosis factor (TNF)‑α, increased serum levels of IL‑10, decreased apoptotic factor Bcl‑2‑associated X and caspase‑3 expression, downregulated HMGB1 and TLR4, NF‑κB and phosphorylated‑NF‑κB p65 expression. When TLR4 expression was inhibited, the anti‑inflammatory effects of VD were attenuated, and HMGB1, TLR4, NF‑κB and p‑NF‑κB p65 expression was increased. VD was able reduce the inflammatory response of asthmatic mice and apoptosis in lung tissue through the HMGB1/TLR4/NF‑κB signaling pathway.

Hypothyrodism as a risk factor of periodontitis and its relation with vitamin D deficiency: mini-review of literature and a case report

Objective

The purpose of this report is to investigate the role and efficiency of the intra-ligamentary injection of vitamin D and calcium in the treatment of chronic periodontitis associated with hypothyroidism.

Design

A 43-year-old female with suspected hypothyroidism who revealed severe chronic periodontitis with grade III mobility. Pre-operative periodontal and systemic control preceded the used intervention. After 3 months, intra-ligamentary injectable vitamin D with calcium was introduced.

Results

Clinical evaluation revealed great improvement of the injected sites. Marked reduction of mobility, pocket depth and bleeding were detected.

Conclusions

Injectabe vitamin D is an adjunctive treatment modality that needs to be discovered in another way. It may provide further solutions for the periodontal regeneration problem. Clinical studies with large sample sizes and long term follow up are needed.

Genome-wide association study in 79,366 European-ancestry individuals informs the genetic architecture of 25-hydroxyvitamin D levels

Vitamin D is a steroid hormone precursor that is associated with a range of human traits and diseases. Previous GWAS of serum 25-hydroxyvitamin D concentrations have identified four genome-wide significant loci (GC, NADSYN1/DHCR7, CYP2R1, CYP24A1). In this study, we expand the previous SUNLIGHT Consortium GWAS discovery sample size from 16,125 to 79,366 (all European descent). This larger GWAS yields two additional loci harboring genome-wide significant variants (P = 4.7×10-9 at rs8018720 in SEC23A, and P = 1.9×10-14 at rs10745742 in AMDHD1). The overall estimate of heritability of 25-hydroxyvitamin D serum concentrations attributable to GWAS common SNPs is 7.5%, with statistically significant loci explaining 38% of this total. Further investigation identifies signal enrichment in immune and hematopoietic tissues, and clustering with autoimmune diseases in cell-type-specific analysis. Larger studies are required to identify additional common SNPs, and to explore the role of rare or structural variants and gene-gene interactions in the heritability of circulating 25-hydroxyvitamin D levels.

Higher maternal vitamin D concentrations are associated with longer leukocyte telomeres in newborns

Gestational vitamin D insufficiency is related with increased risks of various diseases and poor health outcomes later in life. Telomere length at birth or early in life is known to be a predictor of individual health. Both vitamin D and telomere length are related with various health conditions, and vitamin D concentrations are associated with leukocyte telomere lengths in women. We investigated the association between maternal vitamin D concentrations and newborn leukocyte telomere lengths. This cross-sectional study included 106 healthy pregnant women without adverse obstetric outcomes and their offspring. We examined the maternal age, weight before pregnancy, health behaviours, and nutritional intakes, along with each newborn's sex and birthweight, and we measured maternal height, telomere length, total white blood cell count, and glycosylated haemoglobin as covariates. Pearson's correlation coefficients were calculated to evaluate the relationship between the baseline variables and newborn leukocyte telomere lengths. To confirm that there was an independent association between newborn leukocyte telomere lengths and maternal vitamin D concentrations, we performed a stepwise multiple linear regression analysis. Newborn leukocyte telomere lengths correlated positively with maternal leukocyte telomere lengths (r = .76, p < .01), maternal 25-hydroxyvitamin D concentrations (r = .72, p < .01), maternal energy intakes (r = .22, p = .03), and newborn body weights (r = .51, p < .01). In the multivariate model, newborn leukocyte telomere lengths were associated with maternal vitamin D concentrations (β = .33, p < .01). These findings suggest that the maternal vitamin D concentration during pregnancy may be a significant determinant of the offspring's telomere length.

Bioconjugate Strategies for the Induction of Antigen-Specific Tolerance in Autoimmune Diseases

Antigen-specific immunotherapy (ASI) holds great promise for the treatment of autoimmune diseases. In mice, administration of major histocompatibility complex (MHC) binding synthetic peptides which modulate T cell receptor (TCR) signaling under subimmunogenic conditions induces selective tolerance without suppressing the global immune responses. However, clinical translation has yielded limited success. It has become apparent that the TCR signaling pathway via synthetic peptide antigen alone is inadequate to induce an effective tolerogenic immunity in autoimmune diseases. Bioconjugate strategies combining additional immunomodulatory functions with TCR signaling can amplify the antigen-specific immune tolerance and possibly lead to the development of new treatments in autoimmune diseases. In this review, we provide a summary of recent advances in the development of bioconjugates to achieve antigen-specific immune tolerance in vivo, with the discussion focused on the underlying design principles and challenges that must be overcome to target these therapies to patients suffering from autoimmune diseases.

Pemphigus trigger factors: special focus on pemphigus vulgaris and pemphigus foliaceus

Pemphigus is a general term for a rare group of autoimmune diseases which result in the formation of blisters on the skin and oral cavity. Although there is no way to prevent autoimmune diseases, some factors may trigger pemphigus initiation in susceptible individuals or be exacerbated in affected patients. Recognition of these triggers, based on the latest studies and experiences is essential and should be updated every few years. In this study, several triggers, including different drugs and treatments, diseases, vaccines, genetic factors, nutrients, micronutrients, pregnancy, stress, and various other triggers have been discussed. Some possible triggers, such as blood antigens and the effect of seasons have also been discussed briefly. Moreover, some protective factors against pemphigus have been reviewed. Considering the molecular mechanism of pemphigus and immune response alteration during this disease, some possible triggers have been suggested and discussed. Although those triggers may be a real threat, more studies are needed to support these hypotheses.

Vitamin D prenatal programming of childhood metabolomics profiles at age 3 y

Background: Vitamin D deficiency is implicated in a range of common complex diseases that may be prevented by gestational vitamin D repletion. Understanding the metabolic mechanisms related to in utero vitamin D exposure may therefore shed light on complex disease susceptibility.Objective: The goal was to analyze the programming role of in utero vitamin D exposure on children's metabolomics profiles.Design: First, unsupervised clustering was done with plasma metabolomics profiles from a case-control subset of 245 children aged 3 y with and without asthma from the Vitamin D Antenatal Asthma Reduction Trial (VDAART), in which pregnant women were randomly assigned to vitamin D supplementation or placebo. Thereafter, we analyzed the influence of maternal pre- and postsupplement vitamin D concentrations on cluster membership. Finally, we used the metabolites driving the clustering of children to identify the dominant metabolic pathways that were influential in each cluster.Results: We identified 3 clusters of children characterized by 1) high concentrations of fatty acids and amines and low maternal postsupplement vitamin D (mean ± SD; 27.5 ± 11.0 ng/mL), 2) high concentrations of amines, moderate concentrations of fatty acids, and normal maternal postsupplement vitamin D (34.0 ± 14.1 ng/mL), and 3) low concentrations of fatty acids, amines, and normal maternal postsupplement vitamin D (35.2 ± 15.9 ng/mL). Adjusting for sample storage time, maternal age and education, and both child asthma and vitamin D concentration at age 3 y did not modify the association between maternal postsupplement vitamin D and cluster membership (P = 0.0014). Maternal presupplement vitamin D did not influence cluster membership, whereas the combination of pre- and postsupplement concentrations did (P = 0.03).Conclusions: Young children can be clustered into distinct biologically meaningful groups by their metabolomics profiles. The clusters differed in concentrations of inflammatory mediators, and cluster membership was influenced by in utero vitamin D exposure, suggesting a prenatal programming role of vitamin D on the child's metabolome. This trial was registered at clinicaltrials.gov as NCT00920621.

Does vitamin D play a role in autoimmune endocrine disorders? A proof of concept

In the last few years, more attention has been given to the "non-calcemic" effect of vitamin D. Several observational studies and meta-analyses demonstrated an association between circulating levels of vitamin D and outcome of many common diseases, including endocrine diseases, chronic diseases, cancer progression, and autoimmune diseases. In particular, cells of the immune system (B cells, T cells, and antigen presenting cells), due to the expression of 1α-hydroxylase (CYP27B1), are able to synthesize the active metabolite of vitamin D, which shows immunomodulatory properties. Moreover, the expression of the vitamin D receptor (VDR) in these cells suggests a local action of vitamin D in the immune response. These findings are supported by the correlation between the polymorphisms of the VDR or the CYP27B1 gene and the pathogenesis of several autoimmune diseases. Currently, the optimal plasma 25-hydroxyvitamin D concentration that is necessary to prevent or treat autoimmune diseases is still under debate. However, experimental studies in humans have suggested beneficial effects of vitamin D supplementation in reducing the severity of disease activity. In this review, we summarize the evidence regarding the role of vitamin D in the pathogenesis of autoimmune endocrine diseases, including type 1 diabetes mellitus, Addison's disease, Hashimoto's thyroiditis, Graves' disease and autoimmune polyendocrine syndromes. Furthermore, we discuss the supplementation with vitamin D to prevent or treat autoimmune diseases.

A signalome screening approach in the autoinflammatory disease TNF receptor associated periodic syndrome (TRAPS) highlights the anti-inflammatory properties of drugs for repurposing

TNF receptor associated periodic syndrome (TRAPS) is an autoinflammatory disease caused by mutations in TNF Receptor 1 (TNFR1). Current therapies for TRAPS are limited and do not target the pro-inflammatory signalling pathways that are central to the disease mechanism. Our aim was to identify drugs for repurposing as anti-inflammatories based on their ability to down-regulate molecules associated with inflammatory signalling pathways that are activated in TRAPS. This was achieved using rigorously optimized, high through-put cell culture and reverse phase protein microarray systems to screen compounds for their effects on the TRAPS-associated inflammatory signalome. 1360 approved, publically available, pharmacologically active substances were investigated for their effects on 40 signalling molecules associated with pro-inflammatory signalling pathways that are constitutively upregulated in TRAPS. The drugs were screened at four 10-fold concentrations on cell lines expressing both wild-type (WT) TNFR1 and TRAPS-associated C33Y mutant TNFR1, or WT TNFR1 alone; signalling molecule levels were then determined in cell lysates by the reverse-phase protein microarray. A novel mathematical methodology was developed to rank the compounds for their ability to reduce the expression of signalling molecules in the C33Y-TNFR1 transfectants towards the level seen in the WT-TNFR1 transfectants. Seven high-ranking drugs were selected and tested by RPPA for effects on the same 40 signalling molecules in lysates of peripheral blood mononuclear cells (PBMCs) from C33Y-TRAPS patients compared to PBMCs from normal controls. The fluoroquinolone antibiotic lomefloxacin, as well as others from this class of compounds, showed the most significant effects on multiple pro-inflammatory signalling pathways that are constitutively activated in TRAPS; lomefloxacin dose-dependently significantly reduced expression of 7/40 signalling molecules across the Jak/Stat, MAPK, NF-κB and PI3K/AKT pathways. This study demonstrates the power of signalome screening for identifying candidates for drug repurposing.

Dietary factors in rheumatic autoimmune diseases: a recipe for therapy?

Today, we are facing a new era of digitization in the health care system, and with increased access to health care information has come a growing demand for safe, cost-effective and easy to administer therapies. Dietary habits have a crucial influence on human health, affecting an individual's risk for hypertension, heart disease and stroke, as well as influencing the risk of developing of cancer. Moreover, an individual's lifestyle choices can greatly influence the progression and manifestation of chronic autoimmune rheumatic diseases. In light of these effects, it makes sense that the search for additional therapies to attenuate such diseases would include investigations into lifestyle modifications. When considering the complex web of factors that influence autoimmunity, it is not surprising to find that several dietary elements are involved in disease progression or prevention. In this Review, several common nutritional components of the human diet are presented, and the evidence for their effects on rheumatic diseases is discussed.

Is autoimmunology a discipline of its own? A big data-based bibliometric and scientometric analyses

Autoimmunology is a super-specialty of immunology specifically dealing with autoimmune disorders. To assess the extant literature concerning autoimmune disorders, bibliometric and scientometric analyses (namely, research topics/keywords co-occurrence, journal co-citation, citations, and scientific output trends - both crude and normalized, authors network, leading authors, countries, and organizations analysis) were carried out using open-source software, namely, VOSviewer and SciCurve. A corpus of 169,519 articles containing the keyword "autoimmunity" was utilized, selecting PubMed/MEDLINE as bibliographic thesaurus. Journals specifically devoted to autoimmune disorders were six and covered approximately 4.15% of the entire scientific production. Compared with all the corpus (from 1946 on), these specialized journals have been established relatively few decades ago. Top countries were the United States, Japan, Germany, United Kingdom, Italy, China, France, Canada, Australia, and Israel. Trending topics are represented by the role of microRNAs (miRNAs) in the ethiopathogenesis of autoimmune disorders, contributions of genetics and of epigenetic modifications, role of vitamins, management during pregnancy and the impact of gender. New subsets of immune cells have been extensively investigated, with a focus on interleukin production and release and on Th17 cells. Autoimmunology is emerging as a new discipline within immunology, with its own bibliometric properties, an identified scientific community and specifically devoted journals.

Association between Parathyroid Hormone, 25 (OH) Vitamin D, and Chronic Kidney Disease: A Population-Based Study

Identification of the accurate risk factor for CKD remains mandatory to combat the high prevalence of diseases. Growing evidence suggests the association of serum vitamin D with diverse health conditions. However, the relationship between vitamin D, intact parathyroid hormone (PTH), and calcium-phosphate metabolism and development of CKD remains controversial. We conduct this cross-sectional observational study to investigate the association between serum 25 (OH) vitamin D, intact PTH, and calcium and phosphate levels with eGFR and albuminuria, as a surrogate marker of CKD, in a community population. A total of 4080 participants were recruited. The mean age was 58.4 ± 13.3 years and 1480 (36.3%) were men. The mean eGFR was 94.1 ± 26.3 mL/min/1.73 m². The prevalence of CKD was 19.8%. Serum 25 (OH) vitamin D and log intact PTH levels were inversely correlated with eGFR but positively correlated with log albuminuria. Logistic regression analysis identified the log intact PTH as an independent factor associated with eGFR ≤ 60 mL/min/1.73 m² and proteinuria. This association was consistent when serum intact PTH was analyzed as continuous as well as categorical variables (as hyperparathyroidism). The relationship remains significant using resampling subset analysis with comparable baseline characteristics and adjustment for 25 (OH) vitamin D, calcium, and phosphate levels. This finding warranted further research to clarify the causal relationship of PTH/25 (OH) vitamin D with the risk of CKD in the general population.

Functional genomics analysis of vitamin D effects on CD4+ T cells in vivo in experimental autoimmune encephalomyelitis ‬

Vitamin D exerts multiple immunomodulatory functions and has been implicated in the etiology and treatment of several autoimmune diseases, including multiple sclerosis (MS). We have previously reported that in juvenile/adolescent rats, vitamin D supplementation protects from experimental autoimmune encephalomyelitis (EAE), a model of MS. Here we demonstrate that this protective effect associates with decreased proliferation of CD4+ T cells and lower frequency of pathogenic T helper (Th) 17 cells. Using transcriptome, methylome, and pathway analyses in CD4+ T cells, we show that vitamin D affects multiple signaling and metabolic pathways critical for T-cell activation and differentiation into Th1 and Th17 subsets in vivo. Namely, Jak/Stat, Erk/Mapk, and Pi3K/Akt/mTor signaling pathway genes were down-regulated upon vitamin D supplementation. The protective effect associated with epigenetic mechanisms, such as (i) changed levels of enzymes involved in establishment and maintenance of epigenetic marks, i.e., DNA methylation and histone modifications; (ii) genome-wide reduction of DNA methylation, and (iii) up-regulation of noncoding RNAs, including microRNAs, with concomitant down-regulation of their protein-coding target RNAs involved in T-cell activation and differentiation. We further demonstrate that treatment of myelin-specific T cells with vitamin D reduces frequency of Th1 and Th17 cells, down-regulates genes in key signaling pathways and epigenetic machinery, and impairs their ability to transfer EAE. Finally, orthologs of nearly 50% of candidate MS risk genes and 40% of signature genes of myelin-reactive T cells in MS changed their expression in vivo in EAE upon supplementation, supporting the hypothesis that vitamin D may modulate risk for developing MS.

Vitamin D status and its associations with rheumatoid arthritis in Korean women: the Korean National Health and Nutrition Examination Survey 2008-2014

In the present study, vitamin D status and its associations with rheumatoid arthritis in Korean women were investigated. Total 2,162 women’s data from the Korea National Health and Nutrition Examination Survey during 2008–2014 ware analyzed by complex sampling design logistic regression analysis and complex sampling design general linear model. Women who over 19 years old were included, and who has osteoporosis or abnormal parathyroid hormone or renal failure or liver cirrhosis or abnormal creatinine were excluded. Age and body mass index were used as covariate. In the present study, we have shown that vitamin D status were not associated with development of rheumatoid arthritis in Korean women as well were not associated with pain and quality of life in Korean women with rheumatoid arthritis. Based on the present study and considering the effects of vitamin D on fracture and osteoporosis, it can be suggested that additional cohort study and cost-effectiveness analysis are needed.

Serum 25-OH vitamin D levels in systemic sclerosis: analysis of 140 patients and review of the literature

Hypovitaminosis D is increasingly reported in autoimmune diseases. We investigated the 25-OH-vitamin D (25-OH-vitD) levels in systemic sclerosis (SSc) patients, in correlation with disease's features. We measured the 25-OH-vitD serum levels in 140 consecutive patients (F/M 126/15; mean age 61 ± 15.1 years), 91 without (group A) and 49 with (group B) 25-OH-cholecalciferol supplementation. Patients of group A invariably showed low 25-OH-vitD levels (9.8 ± 4.1 ng/ml vs. 26 ± 8.1 ng/ml of group B); in particular, 88/91 (97%) patients showed vitamin D deficiency (<20 ng/ml), with very low vitamin D levels (<10 ng/ml) in 40 (44%) subjects. Only 15/49 (30.6%) patients of group B reached normal levels of 25-OH-vitD (≥30 ng/ml), whereas vitamin D deficiency persisted in 12/49 (24.5%) individuals. Parathormone levels inversely correlated with 25-OH-vitD (r = -0.3, p < 0.0001). Of interest, hypovitaminosis D was statistically associated with autoimmune thyroiditis (p = 0.008), while calcinosis was more frequently observed in patients of group A (p = 0.057). Moreover, we found significantly higher percentage of serum anticentromere antibodies in group B patients with 25-OH-vitD level ≥30 ng/ml (8/15 vs. 6/34; p = 0.017). In literature, hypovitaminosis D is very frequent in SSc patients. An association with disease duration, calcinosis, or severity of pulmonary involvement was occasionally recognized. Hypovitaminosis D is very frequent in SSc and severe in a relevant percentage of patients; furthermore, less than one third of supplemented subjects reached normal levels of 25-OH-vitD. The evaluation of 25-OH-vitD levels should be included in the routine clinical work-up of SSc. The above findings expand previous observations and may stimulate further investigations.

Serum 25-Hydroxyvitamin D3 and BAFF Levels Are Associated with Disease Activity in Primary Sjogren's Syndrome

The study investigated the association between disease activity and serum 25-hydroxyvitamin D3 (25(OH)-D3), B cell activation of the tumor necrosis factor family (BAFF), or β₂ microglobulin in patients with primary Sjogren's syndrome (SS). Sixty-nine primary SS patients and 22 sicca control patients were included in the study. Disease activity was measured with EULAR Sjogren's syndrome disease activity index (ESSDAI). Serum levels of 25(OH)-D3 and β₂ microglobulin were measured by radioimmunoassay and BAFF was measured by an enzyme-linked immunosorbent assay. Serum levels of 25(OH)-D3 were significantly lower in SS patients compared to the sicca controls (p = 0.036). Serum levels of BAFF tended to be higher (p = 0.225) and those of β₂ microglobulin were significantly higher in patients with SS than in sicca controls (p = 0.023). In univariate regression analyses, ESSDAI was significantly associated with serum levels of 25(OH)-D3, BAFF, and β₂ microglobulin. After stepwise backward multivariate linear regression analyses including age and acute phase reactants, ESSDAI was associated with 25(OH)-D3 (β = −0.042, p = 0.015) and BAFF (β = 0.001, p = 0.015) in SS patients. In SS patients, ESSDAI is negatively associated with serum levels of 25(OH)-D3 and positively associated with BAFF.

Low serum vitamin D levels and anti-N-methyl-d-aspartate receptor encephalitis: A case-control study

BACKGROUND

Low vitamin D levels are associated with autoimmunity, but the relationship with anti-N-Methyl-d-aspartate receptor (anti-NMDAR) encephalitis is unknown.

METHODS

25(OH) D levels and clinical and cerebrospinal fluid parameters were evaluated in 30 patients with anti-NMDAR encephalitis and compared with 90 age-, sex-, and season-matched healthy controls.

RESULTS

25(OH)D levels were lower in patients with anti-NMDAR encephalitis compared to controls (43.89 ± 17.91 vs 64.24 ± 24.38 nmol/L, p < 0.001), especially for females (vs males, p = 0.008), aged ≤30 years (vs > 30 years, p = 0.002), severe impairment (mRS ≥ 5) (vs mRS < 5, p = 0.018), and limited treatment responses (vs favorable treatment, p = 0.02). Serum 25(OH)D levels were associated with age (r = 0.393, p = 0.032), and mRS (r = -0.417, p = 0.022).

CONCLUSIONS

Our data showed that serum 25(OH)D levels were reduced in patients with anti-NMDAR encephalitis.