Vitamin D and rheumatoid arthritis: an ongoing mystery

The rs11568820 Variant in the Promoter Region of Vitamin D Receptor Gene Is Associated with Clinical Remission in Rheumatoid Arthritis Patients Receiving Tumor Necrosis Factor Inhibitors

The vitamin D receptor (VDR), binding to the active form of the vitamin, promotes the transcription of numerous genes involved in the proliferation of immune cells, cytokine production and lymphocyte activation. It is known that vitamin D deficiency can influence the risk of developing rheumatoid arthritis (RA) or modulate its disease activity. The aim of this study was to investigate a possible association between the rs11568820 (C > T) polymorphism in the promoter region of VDR gene and the response to therapy with anti-TNF drugs in patients with RA. A total of 178 consecutive Italian patients with RA treated with anti-TNF, naïve for biological therapy, were recruited. Disease activity data were evaluated using specific indices such as DAS28, CDAI and SDAI, measured at the start of therapy and subsequently at 22, 52, 104 and 240 weeks. A statistically significant association emerged between the rs11568820 variant allele of VDR gene and failure to remission assessed by CDAI and SDAI at 52 weeks, and by DAS28, CDAI and SDAI at 104 weeks of follow-up. Furthermore, the variant allele of this polymorphism was observed more frequently in patients who did not undergo sustained remission calculated by CDAI and SDAI. The variant T allele of rs11568820 in VDR gene is associated with a reduced remission rate with anti-TNFα drugs. These data suggest the role of VDR genetic variability in the response to therapy and in the achievement of remission.

Vitamin D and Autoimmune Rheumatic Diseases

Vitamin D is a steroid hormone with potent immune-modulating properties. It has been shown to stimulate innate immunity and induce immune tolerance. Extensive research efforts have shown that vitamin D deficiency may be related to the development of autoimmune diseases. Vitamin D deficiency has been observed in patients with rheumatoid arthritis (RA) and has been shown to be inversely related to disease activity. Moreover, vitamin D deficiency may be implicated in the pathogenesis of the disease. Vitamin D deficiency has also been observed in patients with systemic lupus erythematosus (SLE). It has been found to be inversely related to disease activity and renal involvement. In addition, vitamin D receptor polymorphisms have been studied in SLE. Vitamin D levels have been studied in patients with Sjogren's syndrome, and vitamin D deficiency may be related to neuropathy and the development of lymphoma in the context of Sjogren's syndrome. Vitamin D deficiency has been observed in ankylosing spondylitis, psoriatic arthritis (PsA), and idiopathic inflammatory myopathies. Vitamin D deficiency has also been observed in systemic sclerosis. Vitamin D deficiency may be implicated in the pathogenesis of autoimmunity, and it may be administered to prevent autoimmune disease and reduce pain in the context of autoimmune rheumatic disorders.

Epidemiology of rheumatoid arthritis: genetic and environmental influences

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic systemic disease characterized by articular involvement and extra-articular manifestations. The incidence and prevalence of the disease vary across populations, and there is an ongoing debate on whether a change of RA occurrence over time exists or is due to methodological issues and other biases. Moreover, the disease's onset is related to an interaction of genetic and environmental factors that influence its expression.

AREAS COVERED

This review explores the latest knowledge on RA epidemiology and the possible risk factors associated with its presentation to identify potential warning signs that may in the future help disease management.

EXPERT OPINION

Current epidemiological evidence suggests a significant impact of smoking, sex hormones, and lifestyle status in RA occurrence. However, the association between these variables has not yet been thoroughly studied. Still, their effect must be interpreted as they may present subsequently integral indicators for a more rational approach of the disease.

Vitamin D levels in patients with small and medium vessel vasculitis

OBJECTIVES

To determine the prevalence of vitamin D deficiency in patients with small and medium vessel systemic vasculitis.

METHODS

In this cross-sectional study, 25-hydroxy (OH) vitamin D3 levels were measured in adult patients with systemic small and medium vessel vasculitis including antineutrophil cytoplasmic antibody-associated vasculitis (AAV), cryoglobulinaemic vasculitis (CryV), IgA vasculitis (IgAV) and polyarteritis nodosa (PAN), and age- and sex-matched healthy subjects (HS) and patients with rheumatoid arthritis (RA) as control groups. 25OH vitamin D3 levels<30ng/ml and <20ng/ml were regarded as insufficiency and deficiency, respectively.

RESULTS

Fifty-seven patients (42 AAV, 2 CryV, 8 IgA vasculitis, 5 PAN) with systemic vasculitis, 101 HS, and 111 RA patients were included. The mean 25OH vitamin D3 level was 21.8±14.2ng/mL in patients with vasculitis, 42.7±27.6ng/mL in HS (p<.001) and 20.1±18.47ng/mL in patients with RA (p=.54). Vitamin D insufficiency and deficiency were significantly higher in patients with systemic vasculitis compared to HS (75.4% vs 33.7%, p<.001; %50 vs 21.8%, p<.001, respectively). Vitamin D status was not different in patients with systemic vasculitis compared to RA. There was a negative correlation between vitamin D status and CRP levels (=-.364, p=.007). The multivariate logistic regression analysis showed that renal involvement was significantly associated with vitamin D deficiency/insufficiency in patients with vasculitis (OR 22.5 [95% CI 1.6-128.9].

CONCLUSION

Vitamin D deficiency and insufficiency are more frequent in patients with systemic small and medium vessel vasculitis and RA than HS. Renal involvement is one of the factors associated with vitamin D deficiency/insufficiency in patients with vasculitis.

Analysis of Epigenetic Changes in Vitamin D Pathway Genes in Rheumatoid Arthritis Patients

Background: Rheumatoid arthritis (RA) is an autoimmune inflammatory disease with complex etiopathogenesis launched by multiple risk factors, including epigenetic alterations. RA is possibly linked to vitamin D that is epigenetically active and may alter DNA methylation of certain genes. Therefore, the study aimed to evaluate the relationship between DNA methylation status of vitamin D signaling pathway genes (VDR, CYP24A1, CYP2R1), vitamin D level and associations with RA.Materials and Methods: Totally 76 participants (35 RA patients and 41 healthy controls) were enrolled from a case-control vitamin D and VDR gene polymorphisms study regarding age and vitamin D concentration. CpG islands in promoter regions of the VDR, CYP24A1, CYP2R1 genes were chosen for DNA methylation analysis by means of pyrosequencing. Chemiluminescent microplate immunoassay was used to assess 25(OH)D serum levels. RA clinical data, i.e. the disease activity score C-reactive protein 28 (DAS28 – CRP) as well as patient-reported outcome questionnaires were recorded.Results: The study showed similar methylation pattern in the promoter regions of vitamin D pathway genes in RA and control group with p>0.05 (VDR gene 2.39% vs. 2.48%, CYP24A1 gene 16.02% vs. 15.17% and CYP2R1 2.53% vs. 2.41%). CYP24A1 methylation intensity was significantly higher in compare to methylation intensity of VDR and CYP2R1 genes in both groups (p<0.0001). A tendency of higher vitamin D concentration in cases having methylated VDR (57.57±28.93 vs. 47.40±29.88 nmol/l), CYP24A1 (53.23±26.22 vs. 48.23±34.41 nmol/l) and CYP2R1 (60.41±30.73 vs. 44.54±27.63 nmol/l) genes and a positive correlation between VDR, CYP2R1 methylation intensity and vitamin D level in RA affected participants was revealed (p>0.05). A significantly higher CYP24A1 methylation intensity (p=0.0104) was detected in blood cells of vitamin D deficient (<50 nmol/l) RA patients vs. vitamin D deficient controls.Conclusions: Our data suggests some indirect associations between DNA methylation status of vitamin D pathway genes and vitamin D level in RA.

Etiology and Risk Factors for Rheumatoid Arthritis: A State-of-the-Art Review

Rheumatoid arthritis (RA) is the most common systemic inflammatory rheumatic disease. It is associated with significant burden at the patient and societal level. Extensive efforts have been devoted to identifying a potential cause for the development of RA. Epidemiological studies have thoroughly investigated the association of several factors with the risk and course of RA. Although a precise etiology remains elusive, the current understanding is that RA is a multifactorial disease, wherein complex interactions between host and environmental factors determine the overall risk of disease susceptibility, persistence and severity. Risk factors related to the host that have been associated with RA development may be divided into genetic; epigenetic; hormonal, reproductive and neuroendocrine; and comorbid host factors. In turn, environmental risk factors include smoking and other airborne exposures; microbiota and infectious agents; diet; and socioeconomic factors. In the present narrative review, aimed at clinicians and researchers in the field of RA, we provide a state-of-the-art overview of the current knowledge on this topic, focusing on recent progresses that have improved our comprehension of disease risk and development.

Role of Intestinal Microbiota on Gut Homeostasis and Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory disease that is immune mediated. Patients typically present with synovial inflammation, which gradually deteriorates to investigate severe cartilage and bone damage, affecting an individual's ability to perform basic tasks and impairing the quality of life. When evaluated against healthy controls, patients with RA have notable variations within the constituents of the gut microbiota. The human gastrointestinal tract mucosa is colonized by trillions of commensal microbacteria, which are key actors in the initiation, upkeep, and operation of the host immune system. Gut microbiota dysbiosis can adversely influence the immune system both locally and throughout the host, thus predisposing the host to a number of pathologies, including RA. Proximal intestinal immunomodulatory cells, situated in specific locales within the intestine, are a promising intermediary through which the gastrointestinal microbiota can influence the pathogenesis and progression of RA. In the early stages of the disease, the microbiota appear to differ from those present in healthy controls. This difference may reflect potential autoimmune mechanisms. Research studies evaluating intestinal microbiota have demonstrated that RA is associated with a bacterial population growth or with a decline when judged against control groups. The aim of this review is to examine the studies that connect intestinal dysbiosis with the autoimmune pathways implicated in the pathogenesis of RA.

Vitamin D and VDR Gene Polymorphisms' Association with Rheumatoid Arthritis in Lithuanian Population

Background and Objectives: Rheumatoid arthritis (RA) is a chronic, inflammatory, autoimmune, multi-factorial disease, in which environmental and genetic factors play a major role. RA is possibly linked to vitamin D deficiency and vitamin D receptor (VDR) gene polymorphisms, and research demonstrates that FokI variant susceptibility is associated with increased disease risk among Caucasians. The aim of this study was to evaluate vitamin D deficiency prevalence and its correlation to RA clinical parameters, and to determine the possible association of VDR gene polymorphisms and RA susceptibility in the Lithuanian population. Materials and Methods: Overall, 206 RA patients and 180 age- and sex-matched healthy controls were enrolled at Vilnius University Hospital Santaros Klinikos after informed consent was obtained. The disease activity score 28 C-reactive protein (DAS28 CRP), rheumatoid arthritis impact of disease (RAID) score, and health assessment questionnaire (HAQ) were recorded in RA patients, and 25(OH)D serum levels were evaluated by chemiluminescent microparticle immunoassay for all subjects. Four VDR gene polymorphisms, BsmI, FokI, ApaI, and TaqI, were assessed using real-time PCR instruments and genotyping assays in both groups. Results: The study registered a high prevalence of 25(OH)D deficiency (<50 nmol/L) in RA patients (61.55% (n = 127)). The mean serum concentration in RA patients (44.96 ± 21.92 (nmol/L)) was significantly lower than in the healthy controls (54.90 ± 22.82 (nmol/L)), p < 0.0001. A significant inverse correlation between vitamin D level, DAS28 CRP, and HAQ scores was confirmed in RA patients, with p < 0.05. Still, there was no significant association between the overall risk of RA disease for any allele or genotype of the four VDR loci tested. Conclusions: The study confirmed that vitamin D deficiency is prevalent among RA patients and the 25(OH)D level is significantly lower compared with healthy controls. Lower vitamin D concentration was related with increased disease activity and disability scores. However, genetic analysis of four VDR polymorphisms did not confer the susceptibility to RA in Lithuanian population.

Vitamin D Levels in Patients With Small and Medium Vessel Vasculitis

OBJECTIVES

To determine the prevalence of vitamin D deficiency in patients with small and medium vessel systemic vasculitis.

METHODS

In this cross-sectional study, 25-hydroxy (OH) vitamin D3 levels were measured in adult patients with systemic small and medium vessel vasculitis including antineutrophil cytoplasmic antibody-associated vasculitis (AAV), cryoglobulinaemic vasculitis (CryV), IgA vasculitis (IgAV) and polyarteritis nodosa (PAN), and age- and sex-matched healthy subjects (HS) and patients with rheumatoid arthritis (RA) as control groups. 25OH vitamin D3 levels<30ng/ml and <20ng/ml were regarded as insufficiency and deficiency, respectively.

RESULTS

Fifty-seven patients (42 AAV, 2 CryV, 8 IgA vasculitis, 5 PAN) with systemic vasculitis, 101 HS, and 111 RA patients were included. The mean 25OH vitamin D3 level was 21.8±14.2ng/mL in patients with vasculitis, 42.7±27.6ng/mL in HS (p<.001) and 20.1±18.47ng/mL in patients with RA (p=.54). Vitamin D insufficiency and deficiency were significantly higher in patients with systemic vasculitis compared to HS (75.4% vs 33.7%, p<.001; %50 vs 21.8%, p<.001, respectively). Vitamin D status was not different in patients with systemic vasculitis compared to RA. There was a negative correlation between vitamin D status and CRP levels (=-.364, p=.007). The multivariate logistic regression analysis showed that renal involvement was significantly associated with vitamin D deficiency/insufficiency in patients with vasculitis (OR 22.5 [95% CI 1.6-128.9].

CONCLUSION

Vitamin D deficiency and insufficiency are more frequent in patients with systemic small and medium vessel vasculitis and RA than HS. Renal involvement is one of the factors associated with vitamin D deficiency/insufficiency in patients with vasculitis.

Efficacy of Oral Vitamin Supplementation in Inflammatory Rheumatic Disorders: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: We aimed to provide a systematic review and meta-analysis of randomized controlled trials assessing the effect of oral vitamin supplementation on symptoms and disease activity in patients with rheumatoid arthritis (RA), spondyloarthritis (SpA) and psoriatic arthritis (PsA). Methods: A systematic literature review and meta-analysis of randomized controlled trials including patients with inflammatory rheumatic diseases were performed using MEDLINE, EMBASE and abstracts from recent international rheumatology congresses. Studies were reviewed in accordance with PRISMA guidelines. We analysed clinical outcomes according to each type of vitamin supplementation. Results. The initial search yielded 606 articles. Of these, 13 studies were included in the qualitative synthesis: eight studied vitamin D supplementation, two assessed vitamin E supplementation, two folic acid, and one vitamin K, all of them on RA patients. No studies on SpA or PsA were selected. Oral vitamin supplementations were not associated with a reduction in RA activity (DAS-28 or pain) or RA flares. Conclusions: Despite their beneficial effects, the effects of vitamin supplementation on RA activity, if any, seem to be limited. Evidence on their efficacy on SpA or PsA activity is lacking. However, folic acid supplementation should be suggested to prevent methotrexate-related side effects, and vitamin D should be given to patients with vitamin D deficiency to prevent musculo-skeletal complications.

The Role of Nutritional Factors and Intestinal Microbiota in Rheumatoid Arthritis Development

Evidence about the role of nutritional factors and microbiota in autoimmune diseases, and in rheumatoid arthritis (RA) in particular, has grown in recent years, however many controversies remain. The aim of this review is to summarize the role of nutrition and of the intestinal microbiota in the development of RA. We will focus on selected dietary patterns, individual foods and beverages that have been most consistently associated with RA or with the occurrence of systemic autoimmunity associated with RA. We will also review the evidence for a role of the intestinal microbiota in RA development. We propose that diet and digestive microbiota should be considered together in research, as they interact and may both be the target for future preventive interventions in RA.

Vitamin D Binding Protein (VDBP) and Its Gene Polymorphisms-The Risk of Malignant Tumors and Other Diseases

Vitamin D is an important component of the endocrine system that controls calcium homeostasis and bone mineralization. Because of the very short half-life of free serum vitamin D it is stabilized and transported to target tissues by being bound to the vitamin D binding protein (VDBP). The most common polymorphisms: rs4588 and rs7041 in the vitamin D binding protein gene may correlate with differences in vitamin D status in the serum. This review presents data that relate to the presence of genetic variants in the VDBP gene in correlation with certain diseases, mostly concerning cancers (breast, prostate, pancreatic, lung, colorectal, basal cell carcinoma cancer and cutaneous melanoma) or other related diseases (thyroid autoimmunity disorders, obesity, diabetes mellitus, bone metabolism, rheumatoid arthritis, ankylosing spondylitis, asthma, chronic obstructive pulmonary disease, tuberculosis and coronary artery diseases).

IMMUNOMODULATORY ROLE OF VITAMIN D: CLINICAL IMPLICATIONS IN INFECTIONS AND AUTOIMMUNE DISORDERS

Vitamin D exerts its well-known effects on bone health and calcium-phosphate homeostasis primarily through the vitamin D receptor signaling pathway. Vitamin D also has several extra-skeletal actions and its deficiency is not only implicated in musculoskeletal disorders, but also cardiovascular disorders, diabetes, neurodegenerative conditions and cancers. There is a growing body of research highlighting the link of vitamin D deficiency and alterations in vitamin D signaling with certain infections and autoimmune disorders although the evidence is inconsistent and inconclusive. Vitamin D has been suggested to play a fundamental role in curbing infections and mitigating autoimmune disease processes. The present review was undertaken to explore the promise of vitamin D as a protective agent and a clinically useful therapeutic adjunct against infections and autoimmune diseases and identify knowledge gaps and limitations of the available data for informing future work. An exhaustive search was conducted in established databases including Google Scholar, PubMed, Science Direct and Springer for articles published on vitamin D, immunity, infection and autoimmune disorders. All relevant articles published in the English language between the year 200 and 2020 were retrieved for writing the review. Although a considerable body of evidence highlighting the potential clinical benefits of vitamin D against the development of various autoimmune conditions and for the prevention of infections has emerged over the last decade, the findings are limited by the lack of appropriately designed randomized controlled trials which are needed to formulate precise clinical recommendations.

Vitamin D Deficiency and Rheumatoid Arthritis: Epidemiological, Immunological, Clinical and Therapeutic Aspects

Background/Aim:

Vitamin D displays an immunologic effect which can modulate function of Th17-related cytokines and thereby prevent perpetuation of inflammation in chronic disorders like rheumatoid arthritis (RA). This review aims to conduct a literature review to provide a summary of recent studies addressing the relationship between vitamin D deficiency and RA based on epidemiological, immunological and therapeutic aspects.

Methods:

PubMed, Scopus and Google scholar were searched for relevant papers published between 2000–2018.

Results:

Low intake of vitamin D increases the risk of incident RA, and vitamin D deficiency has been shown to be inversely associated with RA activity in most of these studies. However, characteristics of RA and serum vitamin D status differ across the studies. The results of studies on the effect of supplemental vitamin D in RA vary, from no efficacy to significant improvement in disease activity, as well as quality of life. This should be attributed to variations in dosage of vitamin D, duration of treatment, baseline serum vitamin D in RA patients and characteristics of RA across diverse studies.

Conclusion:

Current data indicate a therapeutic potential for vitamin D in RA. However, further studies are needed to identify an optimal and effective dosage, duration of treatment and patients who will get the best benefit from the treatment.

Association between vitamin D and fatigue in patients with rheumatoid arthritis: a cross-sectional study

OBJECTIVES

In rheumatoid arthritis (RA), fatigue is an important complaint with a significant impact on quality of life. Vitamin D has modulatory effects on cells of the immune system and may potentially affect RA disease activity and thereby RA-related fatigue. The purpose of this study was to explore associations between fatigue and vitamin D status in patients with RA.

DESIGN

Hypothesis-generating cross-sectional study.

SETTING

Scheduled follow-up visits at a hospital-based general rheumatology clinic.

PARTICIPANTS

Patients (n=169) with established RA.

PRIMARY OUTCOME MEASURES AND ANLYSES

Fatigue, assessed by the Chalder fatigue questionnaire, and serum concentrations of 25-hydroxyvitamin D (25(OH)D), assessed by liquid chromatography-tandem mass spectrometry. Associations were analysed by correlation, and multivariate linear regression with adjustments for age, sex, body mass index, RA disease activity as measured by the Disease Activity Score 28-joint count C reactive protein (DAS28-CRP), psychological distress, pain and sleep. Fatigue was also compared across four groups based on the levels of serum 25(OH)D with cut points at 30, 50 and 75 nmol/L using one-way analysis of variance.

RESULTS

Two-thirds of the patients (116/169, 69%) were classified with low RA disease activity, that is, a DAS28-CRP score below 3.2. Their mean (SD) serum 25(OH)D concentration was 56.3 (21.2) nmol/L, with 77 (45.6%) having values below 50 nmol/L and 12 patients (7.1%) below 30 nmol/L. The correlation between fatigue and serum concentrations of 25(OH)D was weak and not statistically significant, r = -0.14 (95% CI: -0.29 to 0.03, p=0.08). In the multivariate model, fatigue was significantly associated with RA disease activity, psychological distress and pain, but not with serum 25(OH)D. Fatigue did not differ across groups with varying levels of serum 25(OH)D.

CONCLUSION

This cross-sectional study found no evidence of association between vitamin D and fatigue in patients with RA.

Circulating levels of free 25(OH)D increase at the onset of rheumatoid arthritis

OBJECTIVE

Epidemiological studies suggest vitamin D deficiency as a potential risk factor for rheumatoid arthritis (RA) development, a chronic autoimmune disorder highly prevalent in indigenous North American (INA) population. We therefore profiled the circulating levels of 25-hydroxyvitaminD [25(OH)D], an active metabolite of vitamin D, in a cohort of at-risk first-degree relatives (FDR) of INA RA patients, a subset of whom subsequently developed RA (progressors).

METHODS

2007 onward, serum samples from INA RA patients and FDR were collected at the time of a structured baseline visit and stored at -20°C. Anti-citrullinated protein antibodies (ACPA), 25(OH)D, hs-CRP, vitamin-D binding protein (VDBP) and parathyroid hormone (PTH) levels were determined using ELISA and rheumatoid factor (RF) seropositivity was determined by nephelometry.

RESULTS

We demonstrate that 25 (OH) D concentrations were lower in winter than summer (P = 0.0538), and that serum 25(OH)D levels were higher in samples collected and stored after 2013 (P<0.0001). Analysis of samples obtained after 2013 demonstrated that 37.6% of study participants were 25(OH)D insufficient (<75nmol/L). Also, seropositive RA patients and FDR had lower 25(OH)D levels compared to ACPA-/FDR (P<0.05, P<0.01 respectively). Linear regression analysis showed 25(OH)D insufficiency was inversely associated with presence of RA autoantibodies. Longitudinal samples from 14 progressors demonstrated a consistent increase in 25(OH)D levels at the time they exhibited clinically detectable joint inflammation, without any significant change in VDBP or PTH levels. Spearman rank correlation analysis showed significant association between 25(OH)D and PTH levels, both in RA patients and progressors at RA onset time.

CONCLUSION

We demonstrate that 25(OH)D levels in serum increased at RA onset in progressors. The potential role that vitamin D metabolites and their downstream effects play in RA transition requires further investigation.

Vitamin D as a Principal Factor in Mediating Rheumatoid Arthritis-Derived Immune Response

Rheumatoid arthritis (RA) is a systemic multifactorial autoimmune disorder. The interactions between diverse environmental and genetic factors lead to the onset of this complex autoimmune disorder. Serum levels of vitamin D (VD) are involved in the regulation of various immune responses. Vitamin D is a key signaling molecule in the human body that maintains calcium as well as phosphate homeostasis. It also regulates the functions of the immune system and, thus, can play a substantial role in the etiology of various autoimmune disorders, including RA. Low serum VD levels have been found to be associated with a higher risk of RA, although this finding has not been replicated consistently. The molecular mechanisms by which VD influences autoimmunity need to be further explored to understand how variation in plasma VD levels could affect the pathogenesis of RA. This mini-review focuses on the influence of VD and its serum levels on RA susceptibility, RA-associated complexities, treatment, and transcriptome products of key proinflammatory cytokines, along with other cytokines that are key regulators of inflammation in rheumatoid joints.

Human host defence peptide LL37 and anti-cyclic citrullinated peptide antibody in early inflammatory arthritis

Objective

Antibodies to citrullinated peptides (anti-CCP) develop in individuals predisposed to rheumatoid arthritis (RA). Neutrophil extracellular traps are a major source of citrullinated antigens and the immunomodulatory host defence peptide LL-37. Vitamin D regulates LL-37 expression. This study assessed the associations of LL-37 and anti-CCP, vitamin D metabolites and vitamin D receptor (VDR) polymorphisms in early inflammatory arthritis (EIA).

Methods

Serum LL-37, 25-hydroxy-vitamin D (25OHvitD) and anti-CCP were measured by ELISA in treatment naïve EIA (n = 181). VDR single nucleotide polymorphisms (Fok1, Bsm1, Apa1, Taq1, Cdx-2) and HLADRB1 shared epitope (SE) alleles were detected by DNA amplification. Associations were tested in multivariable models. Median (25%, 75%) or percentiles are reported.

Results

Participants (70 % female, age 56 [45, 66] years, disease activity score [DAS28ESR3var] 3.7 [2.8, 4.8], 41 % anti-CCP positive, 68 % RA) had low serum 25OHvitD; 20.5 nmol/L (13.9, 29.0). In multivariable models, controlling for age, sex, SE, smoking and vitamin D deficiency, LL37 level (top quartile) associated with anti-CCP seropositivity (OR 22; 95% CI 4 to 104).

Conclusions

Levels of circulating LL-37 are associated with anti-CCP seropositivity. LL37 activity may be one mechanism linking infection and toxin exposure to anti-CCP generation.

Vitamin D Receptor Polymorphism and DHCR7 Contribute to the Abnormal Interplay Between Vitamin D and Lipid Profile in Rheumatoid Arthritis

Emerging evidence suggests a role for 7-dehydrocholesterol reductase (DHCR7) in the crosstalk between cholesterol and vitamin D. Our aim was to evaluate the impact of vitamin D-related polymorphisms and DHCR7 levels in the association between vitamin D deficiency and altered lipid profile in rheumatoid arthritis (RA). Serum 25(OH)-vitamin D, DHCR7 levels and vitamin D-related polymorphisms (VDR-rs2228570, CYP27A1-rs933994, CYP2R1-rs10741657 and DHCR7-rs12785878) were analyzed in 211 RA patients,94 controls and in a prospective cohort of 13 RA patients undergoing TNFα-blockade. Vitamin D was decreased in RA (p < 0.001), correlated to HDL-cholesterol (r = 0.217, p < 0.001) and total-/HDL-cholesterol ratio (r = -0.227, p = 0.004). These correlations were restricted to the VDR-rs2228570 status. Vitamin D deficiency was associated with lower HDL-cholesterol (p = 0.028), higher tender (p = 0.005) and swollen (p = 0.002) joint counts, higher DAS28 (p = 0.018) and HAQ (p = 0.024) in AG/AA-patients but not in their GG-counterparts. The associations among DHCR7, vitamin D and lipid profile followed a seasonal pattern, decreased DHCR7 (p = 0.008) and vitamin D (p < 0.001) and increased total-cholesterol (p = 0.025) being found in winter/spring. Increasing vitamin D upon TNFα-blockade paralleled RA clinical improvement (r = -0.610, p = 0.027) and DHCR7 elevation (r = 0.766, p = 0.002). In conclusion, vitamin D-related polymorphisms and DHCR7 are pivotal to understand the complex, seasonal associations between vitamin D and lipid profile in RA.

Vitamin D, Inflammation and Osteoporosis in Rheumatoid Arthritis

Patients with Rheumatoid Arthritis (RA) commonly develop osteoporosis and fragility fractures. This fact cannot be explained only with the use of glucocorticoids, known to be detrimental for bone health. RA is characterized by a chronic inflammation caused by the continuous activation of innate and adaptive immunity with proinflammatory cytokines overproduction. This process is detrimental for several organs and physiological processes, including the impairment of bone remodeling. We will briefly review the pathogenesis of inflammation-related bone loss in RA, describing well-known and new molecular pathways and focusing on vitamin D and Parathyroid Hormone role.

Efficacy and Safety of 22-Oxa-Calcitriol in Patients with Rheumatoid Arthritis: A Phase II Trial

BACKGROUND Calcitriol (1 alpha, 25-dihydroxy vitamin D3) is a good vitamin D supplement but can cause hypercalcemia. Whereas, 22-oxa-1 alpha, 25-dihydroxy vitamin D3 (22-oxa-calcitriol) has less hypercalcemic activity than calcitriol and is reported to be effective for cell-proliferative diseases. The objective of the study was to compare renal function and blood tests of arthritis patients receiving calcitriol supplements with those receiving 22-oxa-calcitriol supplements. MATERIAL AND METHODS A total of 369 patients with clinically confirmed rheumatoid arthritis were included in this phase II trial. Patients received lactose powder (the placebo group, n=123), 50 000 IU/week of 22-oxa-calcitriol (the treatment group, n=123), or 50 000 IU/week of calcitriol (the control group, n=123) for 6 weeks. At the time of enrollment and after 6 weeks of supplementation, renal function tests, blood tests, and secondary outcome measures were evaluated. One-way ANOVA and the chi-squared test for independence were performed for continuous data and constant data at a 95% of confidence level. RESULTS Both 22-oxa-calcitriol and calcitriol successfully decreased swollen joints in patients with rheumatoid arthritis, and both improved Health Assessment Questionnaire Disease Activity Index scores and serum vitamin D levels. The intensity of improvement of serum vitamin D levels in both groups was the same (P<0.0001, q=0.24); however, calcitriol caused hypercalcemia (P<0.0001, q=12.59). CONCLUSIONS This study found that 22-oxa-calcitriol was a good option for vitamin D supplementation in rheumatoid arthritis patients.

Exposure to Ultraviolet Radiation in the Modulation of Human Diseases

This review focuses primarily on the beneficial effects for human health of exposure to ultraviolet radiation (UVR). UVR stimulates anti-inflammatory and immunosuppressive pathways in skin that modulate psoriasis, atopic dermatitis, and vitiligo; suppresses cutaneous lesions of graft-versus-host disease; and regulates some infection and vaccination outcomes. While polymorphic light eruption and the cutaneous photosensitivity of systemic lupus erythematosus are triggered by UVR, polymorphic light eruption also frequently benefits from UVR-induced immunomodulation. For systemic diseases such as multiple sclerosis, type 1 diabetes, asthma, schizophrenia, autism, and cardiovascular disease, any positive consequences of UVR exposure are more speculative, but could occur through the actions of UVR-induced regulatory cells and mediators, including 1,25-dihydroxy vitamin D₃, interleukin-10, and nitric oxide. Reduced UVR exposure is a risk factor for the development of several inflammatory, allergic, and autoimmune conditions, including diseases initiated in early life. This suggests that UVR-induced molecules can regulate cell maturation in developing organs.

The Impact of Vitamin D on the Immunopathophysiology, Disease Activity, and Extra-Musculoskeletal Manifestations of Systemic Lupus Erythematosus

Over the past two decades it has been increasingly recognized that vitamin D, aside from its crucial involvement in calcium and phosphate homeostasis and the dynamics of the musculoskeletal system, exerts its influential impact on the immune system. The mechanistic roles that vitamin D plays regarding immune activation for combating infection, as well as pathologically and mediating autoimmune conditions, have been progressively unraveled. In vitro and in vivo models have demonstrated that the action of vitamin D on various immunocytes is not unidirectional. Rather, how vitamin D affects immunocyte functions depends on the context of the immune response, in the way that its suppressive or stimulatory action offers physiologically appropriate and immunologically advantageous outcomes. In this review, the relationship between various aspects of vitamin D, starting from its adequacy in circulation to its immunological functions, as well as its autoimmune conditions, in particular systemic lupus erythematosus (SLE), a prototype autoimmune condition characterized by immune-complex mediated inflammation, will be discussed. Concurring with other groups of investigators, our group found that vitamin D deficiency is highly prevalent in patients with SLE. Furthermore, the circulating vitamin D levels appear to be correlated with a higher disease activity of SLE as well as extra-musculoskeletal complications of SLE such as fatigue, cardiovascular risk, and cognitive impairment.

Vitamin D is not useful as a biomarker for disease activity in rheumatoid arthritis

OBJECTIVE

To determine whether there is an association between serum vitamin D levels and the Disease Activity Index in patients with rheumatoid arthritis (RA).

METHODOLOGY

An analytical, retrospective, cross-sectional study was performed at the Hospital Luis Vernaza and Center for Rheumatology and Rehabilitation. We included 18 to 75-year-old patients with a diagnosis of RA according to the 2010 classification criteria, and with a 25-hydroxyvitamin D (25 [OH] D) test within the last 3 months. The activity of the disease was assessed with the 28-joint Disease Activity Score (DAS28) and C-reactive protein (CRP) as an acute-phase reactant. Spearman's rank correlation coefficient was used to establish association between the variables.

RESULTS

A total of 100 RA patients were studied. The mean vitamin D levels were 32.9 ± 11.5 ng/mL. In all, 45% showed insufficient 25 (OH) D and 55% had normal levels; no deficient vitamin D values were found. According to the DAS28-CRP, patients with low, moderate and high activity had an average vitamin D level of 30.4 ± 10.7, 31.9 ± 10.7, and 31.8 ± 12.1 ng/mL, respectively. There were no significant correlations between the disease activity and the serum vitamin D level (P=.60).

CONCLUSION

In our group of RA patients, there was no statistically significant correlation between the levels of vitamin D and the activity of the disease, nor were other determining variables associated with vitamin D levels.

Assessment of Vitamin D in Rheumatoid Arthritis and Its Correlation with Disease Activity

Background:

Vitamin D is believed to have an immunomodulatory and anti-inflammatory action, and its deficiency has been linked with several autoimmune disorders, including rheumatoid arthritis (RA). The relationship between the severity of RA and serum levels of Vitamin D is a subject of immense interest and therapeutic implications.

Materials and Methods:

This was a prospective, comparative study conducted on 100 participants, 50 cases of RA and 50 healthy controls, all in the age group of 18–75 years. Serum Vitamin D levels were measured and compared in cases and controls. Vitamin D levels in RA patients were also assessed in different stages of disease activity to assess the correlation between the two.

Results

Eighty-four percent patients of RA were Vitamin D deficient versus only 34% of controls. The serum Vitamin D levels were also significantly lower in the RA patients (mean value of 21.05 ± 10.02 ng/ml), as compared to the controls (mean value of 32.87 ± 14.16 ng/ml). There was a significant inverse correlation between serum Vitamin D levels and RA disease activity. The mean serum Vitamin D levels were 35.28 ± 9.0 ng/ml, 33.80 ± 4.1 ng/ml, 22.47 ± 6.18 ng/ml, and 14.21 ± 6.97 ng/ml in the remission, low disease activity, moderate disease activity, and high disease activity groups, respectively.

Conclusions

Vitamin D deficiency is more common in RA patients and may be one of the causes leading to development or worsening of the disease.

Vitamin D and autoimmune disease

Vitamin D as a part of the endocrine system is an important component in the interaction between the kidney, bone, parathyroid hormone, and the intestine, which maintains extracellular calcium level within normal limits, in order to keep the vital physiologic process and skeletal integrity. Vitamin D is also associated with hypertension, muscular function, immunity, and ability to encounter infection, autoimmune disease, and cancer. The role of vitamin D in immunity is a feedback reaction of paracrine to eliminate inflammation or to influence CD4 T-cell differentiation and or to increase the function of T suppressor cell or combination between both. The active form of vitamin D produces and maintains self immunologic tolerance, some studies show that 1,25(OH)2D inhibits induction of disease in autoimmune encephalomyelitis, thyroiditis, type-1 diabetes mellitus, inflammatory bowel disease (IBD), systemic lupus erythematosus, and collagen-induced arthritis and Lyme arthritis.