Vitamin D treatment for connective tissue diseases: hope beyond the hype?

Infections and Autoimmunity-The Immune System and Vitamin D: A Systematic Review

Both 25-autoimmunity and(25(OH)D: calcifediol) and its active form, 1,25-dihydroxyvitamin D (1,25(OH)2D: calcitriol), play critical roles in protecting humans from invasive pathogens, reducing risks of autoimmunity, and maintaining health. Conversely, low 25(OH)D status increases susceptibility to infections and developing autoimmunity. This systematic review examines vitamin D's mechanisms and effects on enhancing innate and acquired immunity against microbes and preventing autoimmunity. The study evaluated the quality of evidence regarding biology, physiology, and aspects of human health on vitamin D related to infections and autoimmunity in peer-reviewed journal articles published in English. The search and analyses followed PRISMA guidelines. Data strongly suggested that maintaining serum 25(OH)D concentrations of more than 50 ng/mL is associated with significant risk reduction from viral and bacterial infections, sepsis, and autoimmunity. Most adequately powered, well-designed, randomized controlled trials with sufficient duration supported substantial benefits of vitamin D. Virtually all studies that failed to conclude benefits or were ambiguous had major study design errors. Treatment of vitamin D deficiency costs less than 0.01% of the cost of investigation of worsening comorbidities associated with hypovitaminosis D. Despite cost-benefits, the prevalence of vitamin D deficiency remains high worldwide. This was clear among those who died from COVID-19 in 2020/21-most had severe vitamin D deficiency. Yet, the lack of direction from health agencies and insurance companies on using vitamin D as an adjunct therapy is astonishing. Data confirmed that keeping an individual's serum 25(OH)D concentrations above 50 ng/mL (125 nmol/L) (and above 40 ng/mL in the population) reduces risks from community outbreaks, sepsis, and autoimmune disorders. Maintaining such concentrations in 97.5% of people is achievable through daily safe sun exposure (except in countries far from the equator during winter) or taking between 5000 and 8000 IU vitamin D supplements daily (average dose, for non-obese adults, ~70 to 90 IU/kg body weight). Those with gastrointestinal malabsorption, obesity, or on medications that increase the catabolism of vitamin D and a few other specific disorders require much higher intake. This systematic review evaluates non-classical actions of vitamin D, with particular emphasis on infection and autoimmunity related to the immune system.

Calciphylaxis and its co-occurrence with connective tissue diseases

Calciphylaxis, also known as calcific uremic arteriopathy, is a rare calcification syndrome that presents as ischemic skin necrosis and severe pain. It has a high mortality rate and is characterised by calcification of the small and medium arteries and micro-thrombosis. Calciphylaxis mainly occurs in patients with end-stage renal disease. In recent years, there have been an increasing number of cases of calciphylaxis associated with connective tissue diseases. Given the absence of clear diagnostic criteria for calciphylaxis thus far, an early diagnosis is crucial for designing an effective multidisciplinary treatment plan. In this article, we review the research progress on calciphylaxis and describe its characteristics in the context of connective tissue diseases.

Predicting progression from undifferentiated connective tissue disease to definite connective tissue disease: A systematic review and meta-analysis

PURPOSE

Undifferentiated connective tissue disease (UCTD) encapsulates a broad range of conditions including incomplete forms of systemic lupus erythematosus (SLE) and systemic sclerosis (SSc), some of whom progress to a formal clinical diagnosis over time. This systematic review (SR) and meta-analysis aimed to identify clinical and laboratory features and biomarkers that can predict progression of UCTD.

METHODS

A systematic literature search was carried out on MEDLINE, EMBASE and the Cochrane Central Register of Randomized Controlled Trials. Abstracts and full-text manuscripts were screened by two reviewers. Publications were included if they included at least 20 UCTD patients, a minimum of six months of follow up, and provided data on at least one risk factor for developing a defined CTD. The QUIPS tool was used to assess risk of bias (RoB) and GRADE for grading the quality of the evidence. The study is registered with PROSPERO (ID: CRD42021237725).

RESULTS

Fifty-nine studies were included in the SR, and forty-one in the meta-analysis. The predictors for progression to SLE with the highest certainty of evidence included those with younger age (MD -5.96 [-11.05-0.87 years]), serositis (RR 2.69 [1.61-4.51]), or the presence of anti-dsDNA antibodies (RR 4.27 [1.92-9.51]). For SSc, the highest certainty of evidence included puffy fingers (RR [3.09 [1.48-6.43]), abnormal nailfold changes (NFC) (avascular areas [RR 5.71 (3.03-10.8)] or active or late SSc pattern [RR 2.24 (1.25-4.01)] and anti-topoisomerase-I (RR 1.83 [1.45-2.30]). No novel biomarkers were included in the meta-analysis; however HLA molecules, regulatory T cell shift, pro-inflammatory cytokines and complement activation products were identified as potential predictors for evolution of disease.

CONCLUSIONS

Clinical and immunological parameters may predict which patients with UCTD progress to definitive disease; however, the heterogeneous nature and RoB in most studies limits the ability to apply these results in routine clinical practice. Limited data suggest that some novel biomarkers may provide additional predictive value but these will need larger well designed studies to fully delineate their clinical utility.

Vitamin D Status Among Children With Juvenile Idiopathic Arthritis: A Multicenter Prospective, Non-randomized, Comparative Study

BACKGROUND

Juvenile idiopathic arthritis (JIA) is a chronic autoimmune disease characterized by destructive and inflammatory damage to the joints. The aim in this study was to compare vitamin D levels between children and adolescents, 1-18 years of age, with juvenile idiopathic arthritis (JIA) and a health control group of peers. We considered effects of endogenous, exogenous, and genetic factors on measured differences in vitamin D levels among children with JIA.

METHODS

Our findings are based on a study sample of 150 patients with various variants of JIA and 277 healthy children. The blood level of vitamin D was assessed by calcidiol level. The following factors were included in our analysis: age and sex; level of insolation in three regions of country (center, south, north); assessment of dietary intake of vitamin D; effect of prophylactic doses of cholecalciferol; a relationship between the TaqI, FokI, and BsmI polymorphisms of the VDR gene and serum 25(OH)D concentration.

RESULTS

We identified a high frequency of low vitamin D among children with JIA, prevalence of 66%, with the medial level of vitamin D being within the range of "insufficient" vitamin D. We also show that the dietary intake of vitamin D by children with JIA is well below expected norms, and that prophylactic doses of vitamin D supplementation (cholecalciferol) at a dose of 500-1,000 IU/day and 1,500-2,000 IU/day do not meet the vitamin D needs of children with JIA. Of importance, we show that vitamin D levels among children with JIA are not affected by clinical therapies to manage the disease nor by the present of VDR genetic variants.

CONCLUSION

Prophylactic administration of cholecalciferol and season of year play a determining role in the development of vitamin D deficiency and insufficiency.

Role of Vitamin D in Systemic Sclerosis: A Systematic Literature Review

Background

Systemic sclerosis (SSc) is a chronic multisystem autoimmune condition defined by a complex pathobiology, comprising excessive fibrosis of skin and internal organs, peripheral vasculopathy with endothelial cell dysfunction, inadequate vascular repair and neovascularization, and aberrant immunity. Vitamin D is a steroid hormone with pleiotropic effects beyond its traditional role in calcium and bone homeostasis. Since vitamin D has immunomodulatory, cardioprotective, and antifibrotic properties, it could potentially interfere with SSc pathogenesis. Suboptimal vitamin D levels are classically recognized in scleroderma, irrespective of clinical and serological phenotype.

Aim

This systematic review is aimed at investigating and clarifying the role of vitamin D in SSc and emphasizing the association of vitamin D status with different clinical settings.

Methods and Results

A systematic online search was performed, using PubMed databases to collect articles on the topic of vitamin D in SSc. The final analysis included 40 eligible articles.

Conclusions

Hypovitaminosis D is common in SSc patients and could be associated with clinical and serologic patterns of the disease. Intervention for low serum vitamin D levels in SSc pathogenesis remains controversial, as well as the significance of vitamin D supplementation in such patients.

Prevalence of Subclinical Carotid Atherosclerosis and Vitamin D Deficiency in Egyptian Ankylosing Spondylitis Patients

Objectives

This study aims to investigate the relationship between subclinical carotid atherosclerosis and vitamin D deficiency in Egyptian ankylosing spondylitis (AS) patients and their impact on disease activity.

Patients and methods

This cross-sectional study included 40 AS patients (36 males, 4 females; mean age 45.9±8.4 years; range 33 to 55 years) diagnosed according to the 1984 modified New York criteria with equal number of healthy controls (26 males, 14 females; mean age 48.4±7.8 years; range 31 to 55 years). Patients' histories were taken and clinical examinations were performed. Disease activity was assessed with Bath AS metrology index (BASMI), Bath AS disease activity index (BASDAI), and Bath AS functional index (BASFI) scores. Laboratory evaluation included lipid profile and 25-hydroxyvitamin D [25(OH)D] was determined by enzyme-linked immunosorbent assay. Bilateral carotid intima-media thickness (CIMT) was measured by a high-resolution ultrasound with linear 7-12 MHz transducer. Average of CIMT of right and left common carotid arteries was used.

Results

Statistically significant differences were found between patients and controls in terms of CIMT (p<0.001), 25(OH)D3 (p<0.001) and triglycerides (p=0.02). A significant positive correlation was present between CIMT and disease duration (r=0.74), disease activity scores [BASFI (r=0.60), BASMI (r=0.49), BASDAI (r=0.65)] and lipid profile except for high-density lipoprotein (HDL) that had a negative correlation (r=-0.52). A significant negative correlation was present between 25(OH)D3 levels and CIMT (r=-0.38) and lipid profile except for HDL having a positive correlation (r=0.40).

Conclusion

Prevalence of subclinical carotid atherosclerosis in AS patients compared to the healthy population was associated with high disease activity and functional limitations. In AS patients, 25(OH)D3 deficiency is a risk factor for accelerated atherosclerosis.

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

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

Vitamin D deficiency and thyroid autoantibody fluctuations in patients with Graves' disease - A mere coincidence or a real relationship?

PURPOSE

The aim of this study was to evaluate the association between vitamin D (vitD) and changes in the titers of anti-TSH receptor (TSHR-Abs), antithyroglobulin (Tg-Abs), and antiperoxidase (TPO-Abs) autoantibodies.

MATERIALS/METHODS

The study involved 269 patients with Graves' disease (GD), divided into four subgroups (1-4), i.e. 65 smokers treated with vitD(+) (1), 76 smokers not treated with vitD(-) (2), 61 non-smokers treated with vitD(+) (3) and 67 non-smokers with vitD(-) (4). All thyroid parameters were analyzed at entry and 1, 3, 6, 9 and 12 months later.

RESULTS

The titer of TSHR-Abs in group 3 was significantly lower than in groups 1 and 2 across all time points. At 3, 6 and 12 months, the titers of TSHR-Abs were also lower in group 4 compared to groups 1 and 2. At 9 months, the titers in group 3 were lower than in all other groups. There was a significant inverse correlation between baseline levels of vitD and baseline titers of Tg-Abs (in group 1 only), Tg-Abs after 12 months (in group 1 only), TPO-Abs after 12 months (in groups 1 and 3), fT4 (in group 4 only), and a significant positive correlation with TPO-Abs (in group 2 only). VitD levels at 12 months were inversely correlated with Tg-Abs in group 1.

CONCLUSIONS

VitD measurements in patients with GD, especially smokers with an increased TSHR-Ab titers before 131I therapy, are recommended. Immunological remission is more likely in patients with GD who receive vitD, particularly smokers.

Vitamin D and Spondyloarthritis: Review of the Literature

Background:

Spondyloarthritides (SpAs) encompass heterogeneous diseases sharing similar genetic background, pathogenic mechanisms, and phenotypic features. Vitamin D is essential for calcium metabolism and skeletal homeostasis. Some recent evidences reported supplemental functions of vitamin D, such as modulation of inflammatory reactions.

Objective:

To analyze published data about a possible association between vitamin D and SpAs.

Results:

Vitamin D could play a role in immune reactions, influencing both immune and adaptive response. Vitamin D deficiency is more frequent in SpAs than in general population: an active and more severe disease infers patients’ mobility and reduces sunlight exposure. Quiescent inflammatory bowel disease, frequently associated with SpAs, could worsen vitamin D deficiency. All the parameters related to UVB exposure are the most important determinants for vitamin D status and need to be considered evaluating the vitamin D levels in SpAs.

Apart from musculoskeletal problems, patients affected by SpAs frequently suffer from other comorbidities, especially cardiovascular diseases and osteoporosis, and vitamin D status could have a relevance in this field. Bone is involved in SpAs with a dualistic role, coexisting trabecular bone resorption and new bone formation.

It seems rational to monitor vitamin D levels in SpA subjects and to target it to global health threshold.

Conclusion:

Literature data were not completely in agreement about a possible relation between poor vitamin D status and onset or worse disease course of SpAs. In fact, these results come from cross-sectional studies, which affect our ability to infer causality. Therefore, large, randomized controlled trials are needed.

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.

Endothelial Progenitor Cells: New Targets for Therapeutics for Inflammatory Conditions With High Cardiovascular Risk

Over the past decade, we have witnessed an exponential growth of interest into the role of endothelial progenitor cells (EPCs) in cardiovascular disease. While the major thinking revolves around EPC angiogenic repair properties, we have used a hypothesis-driven approach to discover disease-related defects in their characteristics and based on these findings, have identified opportunities for functional enhancement, which offer an exciting avenue for translation into clinical intervention. In this review, we focus on two groups; circulating myeloid angiogenic cells (MACs) and late outgrowth endothelial colony forming cells (ECFCs), and will discuss the unique properties and defects of each population, as new insights have been gained into the potential function of each sub-type using current techniques and multiomic technology. We will discuss their role in inflammatory disorders and alterations in mitochondrial function. In addition, we share key insights into the glycocalyx, and propose this network of membrane-bound proteoglycans and glycoproteins, covering the endothelium warrants further investigation in order to clarify its significance in ECFC regulation of vascularization and angiogenesis and ultimately for potential translational therapeutic aspects.

Vitamin D3 repressed astrocyte activation following lipopolysaccharide stimulation in vitro and in neonatal rats

Vitamin D3 has been reported to be an immunity modulator and high levels of vitamin D3 are correlated with a decreased risk for developing diseases in the central nervous system. Astrocytes are important immune cells and contribute toward inflammation during neurological diseases. The vitamin D receptor has been reported to be expressed in astrocytes; however, the effect of vitamin D3 on astrocyte activation has not been studied. Here, we found that lipopolysaccharide stimulation in astrocytes could enhance the expression of vitamin D receptor and Cyp27B1, which encodes the enzyme for converting vitamin D3 into its active form. Vitamin D3 suppressed the expression of proinflammatory cytokines tumour necrosis factor-α, interleukin-1β, vascular endothelial growth factor, and also TLR4 in activated astrocytes. Astrocyte activation was further found to be suppressed after the administration of vitamin D3 in neonatal rats injected with lipopolysaccharide in vivo. We demonstrated the antiactivation effect of vitamin D3 in astrocytes after lipopolysaccharide stimulation. Considering the function of reactive astrocytes in augmenting inflammatory response in neurodegeneration and brain injury, the finding that vitamin D3 administration may inhibit astrocyte activation may be potentially useful for the treatment of central nervous system disorders.

Vitamin D and juvenile systemic lupus erythematosus: Lights, shadows and still unresolved issues

Systemic lupus erythematosus (SLE) and juvenile SLE (jSLE) are autoimmune disorders naturally associated with several genetic, environmental, hormonal, and immunological contributing factors. It has been assumed that vitamin D deficiency may have a role in the immune activation of patients with SLE and play an active part in many comorbidities and even complications. A host of clinical studies suggested that vitamin D exerts inhibitory effects on many immunological abnormalities associated with SLE, also in children and adolescents, while different reports have hypothesized that vitamin D may be associated with accelerated cardiovascular disease in SLE. This review updates and summarizes the information related to the immunoregulatory effects of vitamin D and its importance in jSLE, discusses the innumerable correlations between vitamin D and disease activity, including clinical expression and gene polymorphisms of vitamin D receptor as well as the recommendations for vitamin D supplementation in these patients. Despite the excitement raised by many data obtained about vitamin D and its influence on several aspects of the disease, further well-designed perspective trials are required to define the exact role that vitamin D may have in the management of both SLE and jSLE.

Vitamin D and systemic lupus erythematosus - The hype and the hope

Over the past 20years, much has been written about the potential role of vitamin D in on adverse health outcomes. In recent years, evidence has accumulated regarding the effect of vitamin D on the immune system, and its different cells. Some studies have noted lower vitamin D concentrations in patients with SLE. These epidemiological data still not answer the question: is vitamin D deficiency the cause or the effect? To answer this, we will discuss the association between vitamin D deficiency and SLE and review the evidence from interventional studies.

Determination of Vitamin D Status in a Population of Ecuadorian Subjects

INTRODUCTION

Vitamin D is a preprohormone known to play a key role in phosphocalcic metabolism; its main source comes from the synthesis at the skin level by ultraviolet (UV) radiation.

OBJECTIVE

The purpose of this study was to determine the levels of vitamin D in an Ecuadorian population.

MATERIALS AND METHODS

Retrospective study of Ecuadorian subjects from the city of Guayaquil, who had an initial study of 25 (OH)-D serum, as the indicator of Vitamin D status, in the period of 2015-2016.

RESULTS

A total of 269 Ecuadorian subjects were analyzed, with a mean age of 54.73 ± 16.58; 85% (229) were females and 15% (41) males; mean vitamin D was 27.29 ± 10.12 ng/dl [6.41-88.74]; 70% of the population showed levels below 30 ng/dL of vitamin D, whereas only 30% (81) had normal values. 69% (185) had levels between 29 and 10 ng/dl and 1% (3) levels below 10 ng/dl. High levels of vitamin D were evidenced in the summer months in relation to the winter months.

CONCLUSION

It is evident that, despite the location of Ecuador and the intensity of UV rays it receives throughout the year, Ecuadorian subjects have insufficient levels of vitamin D.

Are Systematic Screening for Vitamin D Deficiency and Vitamin D Supplementation Currently Feasible for Ankylosing Spondylitis Patients?

Beyond its role in calcium and phosphorus metabolism for healthy bone mineralization, there is increasing awareness for vitamin D contribution in modulation of immune reactions. Given that ankylosing spondylitis (AS) is a chronic inflammatory disease involving excess immune/inflammatory activity and posing great therapeutic challenges, it is conceivable to claim that vitamin D treatment may be a safe and effective treatment to influence or modify the primary disease and its related comorbidities. Nevertheless, consistent body of research supporting this hypothesis is still lacking. In this paper, we examine whether systematic screening and treatment for vitamin D deficiency are feasible at present. We will review the immunomodulatory role of vitamin D and its contribution in initiation and progression of AS, as well as how they would determine the occurrence of comorbid conditions. Our conclusion is that despite the overwhelmed interest about vitamin D treatment in AS patients, systematic screening and treatment for vitamin D deficiency of all AS patients are not feasible as yet. This stresses the need for further extensive well-designed research to prove vitamin D efficacy in AS beyond bone protection. And if utility is proven, personalized treatment regimes, duration of treatment, and threshold values for vitamin D should be provided.