Vitamin D and systemic lupus erythematosus: state of the art

Vitamin D3 mitigates autoimmune inflammation caused by activation of myeloid dendritic cells in SLE

Systemic lupus erythematosus (SLE) is an autoimmune disease in which defective T cells, immune complex deposition and other immune system alterations contribute to pathological changes of multiple organ systems. The vitamin D metabolite c is a critical immunomodulator playing pivotal roles in the immune system. Epidemiological evidence indicates that vitamin D deficiency is correlated with the severity of SLE. Our aim is to investigate the effects of 1,25(OH)2D3 (VitD3) on the activation of myeloid dendritic cells (mDCs) by autologous DNA-containing immune complex (DNA-ICs), and the effects of VitD3 on immune system balance during SLE. We purified DNA-ICs from the serum of SLE patients and isolated mDCs from normal subjects. In vitro studies showed that DNA-ICs were internalized and consumed by mDCs. VitD3 blocked the effects of DNA-ICs on RelB, IL-10 and TNF-α in mDCs. Further analysis indicated that DNA-ICs stimulated histone acetylation in the RelB promoter region, which was inhibited by VitD3. Knockdown of the histone deacetylase 3 gene (HDAC3) blocked these VitD3-mediated effects. Co-culture of mDCs and CD4+ T cells showed that VitD3 inhibited multiple processes mediated by DNA-ICs, including proliferation, downregulation of IL-10, TGF-β and upregulation of TNF-α. Moreover, VitD3 could also reverse the effects of DNA-IC-induced imbalance of CD4+  CD127-  Foxp3+ T cells and CD4+  IL17+ T cells. Taken together, our results indicated that autologous DNA-ICs stimulate the activation of mDCs in the pathogenesis of SLE, and VitD3 inhibits this stimulatory effects of DNA-ICs by negative transcriptional regulation of RelB gene and maintaining the Treg/Th17 immune cell balance. These results suggest that vitamin D may have therapeutic value for the treatment of SLE.

Darkness hormone or daylight hormone in women with systemic lupus erythematosus?

INTRODUCTION

In this study, it was aimed to compare the effects of both melatonin and 25-hydroxyvitamin D3, defined as an immune modulator, on laboratory diagnostic criteria parameters and disease activity in patients with systemic lupus erythematosus (SLE).

METHODS

The study included 56 women with SLE and 40 healthy women (control group). Melatonin and 25-hydroxyvitamin D3 levels of patients and healthy individuals included in the study were examined. In addition, leukocytes, lymphocytes, platelets, C3, C4, anti-double-stranded DNA (Anti-dsDNA), antinuclear antibody, and SLE disease activity index (SLEDAI) were analyzed in women with SLE. Patients were divided into four subgroups according to SLEDAI.

RESULTS

Melatonin and 25-hydroxyvitamin D3 levels of women with SLE were lower than healthy women (p < 0.001). Both melatonin and 25-hydroxyvitamin D3 levels were not correlated with laboratory diagnostic criteria parameters. Only 25-hydroxyvitamin D3 levels were correlated with leukocyte levels (p < 0.01). There was no significant difference between the melatonin levels of the subgroups. The 25-hydroxyvitamin D3 levels of the subgroup without disease activity were higher than levels of the subgroups with disease activity (p < 0.05). There was a negative correlation between SLEDAI score and 25-hydroxyvitamin D3 levels (p < 0.05).

CONCLUSION

Women with SLE had lower melatonin and 25-hydroxyvitamin D3 levels than healthy women. On the other hand, parameters of laboratory diagnostic criteria of SLE disease were not related. Only 25-hydroxyvitamin D3 levels were inversely related leukocyte levels. SLE disease activity was not correlated with melatonin levels but negatively correlated with 25-hydroxyvitamin D3 levels. Key Points • Women with SLE have low levels of melatonin and 25-hydroxyvitamin D3. • Melatonin and 25-hydroxyvitamin D3 levels are not related to the laboratory diagnostic criteria parameters for SLE disease. • Low levels of melatonin and 25-hydroxyvitamin D3 may be a factor in the unbalanced immune system of SLE. • Supplementation of melatonin and 25-hydroxyvitamin D3 may be recommended for women patients with SLE.

Diet and Systemic Lupus Erythematosus (SLE): From Supplementation to Intervention

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory disease characterised by immune dysregulation affecting multiple organs. Current anti-inflammatory treatments used in SLE are associated with unwanted side-effects. Dietary supplementation has been suggested as a safe and effective addition to conventional treatment, but evidence of efficacy in SLE or preventing associated comorbidities is uncertain.

METHODS

We identified literature on clinical trials focused on nutritional interventions in SLE aiming to improve inflammation and comorbidities. A systematic-type search on Embase, Medline, and the Cochrane Library, was conducted to identify nutritional interventions among SLE patients in the past 15 years that met our inclusion criteria.

RESULTS

We identified 2754 articles, of which 14 were eligible for inclusion based on our set criteria and were subsequently quality assessed. Vitamin D or E supplementation was associated with respective improvement of inflammatory markers or antibody production, but not disease activity scores in most studies. Despite their expected synergistic actions, the addition of curcumin on vitamin D supplementation had no additional effects on disease activity or inflammatory markers. Trials of omega-3 fatty acid supplementation presented significant reductions in ESR, CRP, disease activity, inflammatory markers, and oxidative stress, and improved lipid levels and endothelial function, while a low glycaemic index (GI) diet showed evidence of reduced weight and improved fatigue in patients.

CONCLUSIONS

Different dietary guidelines can therefore be implicated to target specific SLE symptoms or therapeutic side-effects. This systematic review highlights the scarcity of larger and longer in duration trials with homogenous methodologies and verifiable outcomes to assess disease progression.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

The Impact of Obesity and a High-Fat Diet on Clinical and Immunological Features in Systemic Lupus Erythematosus

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with multiple organ involvement predominantly affecting women of childbearing age. Environmental factors, as well as genetic predisposition, can cause immunological disturbances that manifest as SLE. A habitual high-fat diet and obesity have recently been reported to play a role in the pathogenesis of autoimmune diseases. The frequency of obesity is higher in patients with SLE than in general populations. Vitamin D and adipokines, such as leptin and adiponectin, are possible mediators connecting obesity and SLE. Serum leptin and adiponectin levels are elevated in patients with SLE and can impact innate and adaptive immunity. Vitamin D deficiency is commonly observed in SLE. Because vitamin D can modulate the functionality of various immune cells, we review vitamin D supplementation and its effects on the course of clinical disease in this work. We also discuss high-fat diets coinciding with alterations of the gut microbiome, or dysbiosis. Contingent upon dietary habits, microbiota can be conducive to the maintenance of immune homeostasis. A high-fat diet can give rise to dysbiosis, and patients who are affected by obesity and/or have SLE possess less diverse microbiota. Interestingly, a hypothesis about dysbiosis and the development of SLE has been suggested and reviewed here.

Functional effects of vitamin D: From nutrient to immunomodulator

Vitamin D can be obtained from the endogenous synthesis in the epidermis by exposure to UVB light, and from foods and supplements in the form of ergocalciferol (vitamin D₂) and cholecalciferol (vitamin D₃). The main metabolite used to measure vitamin D serum status is calcidiol [25(OH)D]. However, its active metabolite calcitriol [1α,25(OH)₂D] performs pleiotropic effects in the cardiovascular, neurological, and adipose tissue as well as immune cells. Calcitriol exerts its effects through genomic mechanisms modulated by the nuclear vitamin D receptor (VDR)/retinoid X receptor (RXR) complex, to bind to vitamin D response elements (VDRE) in target genes of several cells such as activated T and B lymphocytes, neutrophils, macrophages, and dendritic cells; besides of its genomic mechanisms, VDR performs novel non-genomic mechanisms that involve its membrane expression and soluble form; highlighting that vitamin D could be an immunomodulatory nutrient that plays a key role during physiological and pathological events. Therefore, the aim of this comprehensive literature review was to describe the most relevant findings of vitamin D dietary sources, absorption, synthesis, metabolism, and factors that influence its serum status, signaling pathways, and biological effects of this immunonutrient in the health and disease.

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.

Extra-Skeletal Effects of Vitamin D

The vitamin D receptor is expressed in multiple cells of the body (other than osteoblasts), including beta cells and cells involved in immune modulation (such as mononuclear cells, and activated T and B lymphocytes), and most organs in the body including the brain, heart, skin, gonads, prostate, breast, and gut. Consequently, the extra-skeletal impact of vitamin D deficiency has been an active area of research. While epidemiological and case-control studies have often suggested a link between vitamin D deficiency and conditions such as type 1 and type 2 diabetes, connective tissue disorders, inflammatory bowel disorders, chronic hepatitis, food allergies, asthma and respiratory infections, and cancer, interventional studies for the most part have failed to confirm a causative link. This review examines available evidence to date for the extra-skeletal effects of vitamin D deficiency, with a focus on randomized controlled trials and meta-analyses.

Raising awareness on the therapeutic role of cholecalciferol in CKD: a multidisciplinary-based opinion

Vitamin D is recognized to play an essential role in health and disease. In kidney disease, vitamin D analogs have gained recognition for their involvement and potential therapeutic importance. Nephrologists are aware of the use of oral native vitamin D supplementation, however, uncertainty still exists with regard to the use of this treatment option in chronic kidney disease as well as clinical settings related to chronic kidney disease, where vitamin D supplementation may be an appropriate therapeutic choice. Two consecutive meetings were held in Florence in July and November 2016 comprising six experts in kidney disease (N = 3) and bone mineral metabolism (N = 3) to discuss a range of unresolved issues related to the use of cholecalciferol in chronic kidney disease. The panel focused on the following six key areas where issues relating to the use of oral vitamin D remain controversial: (1) vitamin D and parathyroid hormone levels in the general population, (2) cholecalciferol in chronic kidney disease, (3) vitamin D in cardiovascular disease, (4) vitamin D and renal bone disease, (5) vitamin D in rheumatological diseases affecting the kidney, (6) vitamin D and kidney transplantation.

Vitamin D deficiency as a risk factor for the development of autoantibodies in patients with ASIA and silicone breast implants: a cohort study and review of the literature

The development of autoimmunity and/or autoimmune diseases is multifactorial. Vitamin D is one of the factors that might play a role. We postulated that both the presence of adjuvants and insufficient levels of vitamin D may result in the development of autoimmunity in patients with autoimmune/inflammatory syndrome induced by adjuvants (ASIA) in relation to silicone implant incompatibility. We measured vitamin D levels in 135 patients with ASIA in relation to silicone implant incompatibility and related findings to the presence of autoantibodies that are commonly used to diagnose systemic autoimmune diseases. Furthermore, we systematically reviewed the literature regarding vitamin D deficiency as a risk factor for the development of autoantibodies. Vitamin D measurements were available for analysis in 131 of 135 patients with ASIA in relation to SIIS. Twenty-three patients (18%) tested positive for autoantibodies, from which 18 patients (78%) had either a vitamin D deficiency or insufficiency (median vitamin D level 60.5 mmol/L), whereas five patients (22%) had sufficient vitamin D levels. The risk to develop autoantibodies was significantly increased in vitamin D deficient and/or insufficient patients [RR 3.14; 95% CI, 1.24–7.95; p = 0.009]. Reviewed literature suggested an association between vitamin D levels and the presence and/or titer levels of autoantibodies in different autoimmune diseases. From our current study and from our review of the literature, we conclude that vitamin D deficiency is related to the presence of autoantibodies. Whether vitamin D supplementation results in a decrease of autoimmunity needs to be studied prospectively.

Skin Involvement and Pulmonary Hypertension Are Associated with Vitamin D Insufficiency in Scleroderma

Vitamin D status has been linked to immune system and autoimmune disorders; in fact, low levels of vitamin D are common in many autoimmune disorders. The aims of our study were to assess the prevalence of vitamin D insufficiency and the possible correlation with clinical parameters in systemic sclerosis (SSc). We recruited 40 patients (38 female and two male) with scleroderma and 40 healthy controls matched for age and gender. Demographic and clinical parameters were recorded and the 25-hydroxivitamin D3 serum levels were measured. Serum 25-hydroxivitamin D3 levels were significantly lower in patients with systemic sclerosis than in the control group. The prevalence of 25-hydroxivitamin D3 insufficiency was 50% in the patients and 22.5% in the control group. A statistically significant association was observed between the insufficiency of 25-hydroxivitamin D3 and skin involvement (p = 0.02) and echocardiography systolic pulmonary artery pressure >35 mmHg (p = 0.02). Our data show that the systemic sclerosis group has significantly lower serum 25-hydroxivitamin D3 concentrations compared to the control group; skin involvement and pulmonary hypertension are associated with vitamin D3 insufficiency.

The global burden of SLE: prevalence, health disparities and socioeconomic impact

Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease that can potentially lead to serious organ complications and even death. Its global burden - in terms of incidence and prevalence, differential impact on populations, economic costs and capacity to compromise health-related quality of life - remains incompletely understood. The reported worldwide incidence and prevalence of SLE vary considerably; this variation is probably attributable to a variety of factors, including ethnic and geographic differences in the populations being studied, the definition of SLE applied, and the methods of case identification. Despite the heterogeneous nature of the disease, distinct patterns of disease presentation, severity and course can often be related to differences in ethnicity, income level, education, health insurance status, level of social support and medication compliance, as well as environmental and occupational factors. Given the potential for the disease to cause such severe and widespread organ damage, not only are the attendant direct costs high, but these costs are sometimes exceeded by indirect costs owing to loss of economic productivity. As an intangible cost, patients with SLE are, not surprisingly, likely to endure considerably reduced health-related quality of life.