Cytokines, 25-OH vit D and disease activity in patients with juvenile-onset systemic lupus erythematosus

Vitamin D and systemic lupus erythematosus: Causality and association with disease activity and therapeutics

The major role of bioactive vitamin 1,25-dihydroxyvitamin D3 (1,25(OH)2D or calcitriol) is to maintain the levels of calcium and phosphorus to achieve bone and mineral homeostasis. Dietary intake and adequate natural light exposure are the main contributors to normal vitamin D status. In addition to regulating metabolism, vitamin D exerts various immunomodulatory effects that regulate innate and adaptive immunity through immune effector cells such as monocytes, macrophages, T and B lymphocytes, and natural killer cells and nonimmune cells that express vitamin D receptors. Systemic lupus erythematosus (SLE) is an autoimmune disease with an unknown etiology, and the association between vitamin D and SLE remains incompletely understood. Given that the current treatment for SLE relies heavily on corticosteroids and that SLE patients tend to have low vitamin D status, vitamin D supplementation may help to reduce the dosage of corticosteroids and/or attenuate disease severity. In this review, we address the associations between vitamin D and several clinical aspects of SLE. In addition, the underlying immunomodulatory mechanisms accounting for the potential vitamin D-mediated therapeutic effects are discussed. Finally, several confounding factors in data interpretation and the execution of clinical trials and perspectives targeting vitamin D supplementation in patients with SLE are also addressed.

The role of vitamin D in pediatric systemic lupus erythematosus - a double pawn in the immune and microbial balance

Having increased popularity during the Covid-19 pandemic, vitamin D3 is currently impressing thanks to the numerous researches aimed at its interactions with the body's homeostasis. At the same time, there is a peak in terms of recommendations for supplementation with it. Some of the studies focus on the link between autoimmune diseases and nutritional deficiencies, especially vitamin D3. Since the specialized literature aimed at children (patients between 0-18 years old) is far from equal to the informational diversity of the adult-centered branch, this review aims to bring up to date the relationship between the microbial and nutritional balance and the activity of pediatric systemic lupus erythematosus (pSLE). The desired practical purpose resides in a better understanding and an adequate, individualized management of the affected persons to reduce morbidity. The center of the summary is to establish the impact of hypovitaminosis D in the development and evolution of pediatric lupus erythematosus. We will address aspects related to the two entities of the impact played by vitamin D3 in the pathophysiological cascade of lupus, but also the risk of toxicity and its effects when the deficiency is over supplemented (hypervitaminosis D). We will debate the relationship of hypovitaminosis D with the modulation of immune function, the potentiation of inflammatory processes, the increase of oxidative stress, the perfusion of cognitive brain areas, the seasonal incidence of SLE and its severity. Finally, we review current knowledge, post-pandemic, regarding the hypovitaminosis D - pSLE relationship.

Can vitamin D be an adjuvant therapy for juvenile rheumatic diseases?

Vitamin D, known for its essential role in calcium and bone homeostasis, has multiple effects beyond the skeleton, including regulation of immunity and modulation of autoimmune processes. Several reports have shown suboptimal serum 25 hydroxyvitamin D [25(OH)D] levels in people with different inflammatory and autoimmune rheumatic conditions, and an association between 25(OH)D levels, disease activity and outcomes. Although most available data pertain to adults, insights often are extended to children. Juvenile rheumatic diseases (JRDs) are a significant health problem during growth because of their complex pathogenesis, chronic nature, multisystemic involvement, and long-term consequences. So far, there is no definitive or clear evidence to confirm the preventive or therapeutic effect of vitamin D supplementation in JRDs, because results from randomized controlled trials (RCTs) have produced inconsistent outcomes. This review aims to explore and discuss the potential role of vitamin D in treating selected JRDs. Medline/PubMed, EMBASE, and Scopus were comprehensively searched in June 2023 for any study on vitamin D supplementary role in treating the most common JRDs. We used the following keywords: "vitamin D" combined with the terms "juvenile idiopathic arthritis", "juvenile systemic scleroderma", "juvenile systemic lupus erythematosus", "juvenile inflammatory myopathies", "Behcet disease", "periodic fever syndromes" and "juvenile rheumatic diseases". Observational studies have found that serum 25(OH)D concentrations are lower in juvenile idiopathic arthritis, juvenile systemic lupus erythematosus, juvenile systemic scleroderma, Behcet disease and proinflammatory cytokine concentrations are higher. This suggests that vitamin D supplementation might be beneficial, however, current data are insufficient to confirm definitively the complementary role of vitamin D in the treatment of JRDs. Considering the high prevalence of vitamin D deficiency worldwide, children and adolescents should be encouraged to supplement vitamin D according to current recommendations. More interventional studies, especially well-designed RCTs, assessing the dose-response effect and adjuvant effect in specific diseases, are needed to determine the potential significance of vitamin D in JRDs treatment.

Cytokines in Systemic Lupus Erythematosus-Focus on TNF-α and IL-17

Systemic lupus erythematosus (SLE) is an autoimmune disorder known for its complex pathogenesis, in which cytokines play an essential role. It seems that the modulation of these cytokines may impact disease progression, being considered potential biomarkers. Thus, TNF (tumor necrosis factor)-α and IL (interleukin)-17 are molecules of great interest in SLE. TNF-α plays a dual role in SLE, with both immunosuppressive and proinflammatory functions. The role of IL-17 is clearly described in the pathogenesis of SLE, having a close association with IL-23 in stimulating the inflammatory response and consecutive tissue destruction. It appears that patients with elevated levels of these cytokines are associated with high disease activity expressed by the SLE disease activity index (SLEDAI) score, although some studies do not confirm this association. However, TNF-α and IL-17 are found in increased titers in lupus patients compared to the general population. Whether inhibition of these cytokines would lead to effective treatment is under discussion. In the case of anti-TNF-α therapies in SLE, the possibility of ATIL (anti-TNF-induced lupus) is a serious concern that limits their use. The use of anti-IL-17 therapies in SLE is a promising option, but not yet approved. Future studies of these cytokines in large cohorts will provide valuable information for the management of SLE.

The changes of Treg and Th17 cells relate to serum 25(OH)D in patients with initial-onset childhood systemic lupus erythematosus

Background

T helper 17 (Th17) cells and regulatory T cells (Treg) are known to play a crucial role in the pathogenesis of systemic lupus erythematosus (SLE). Improving the balance between Treg and Th17 cells can be a promising new therapeutic target in SLE patients. Vitamin D has a significant impact on the immune inflammatory process and the immune cells involved in this process. The purpose of this study is to investigate the relationship between Th17, Treg, cytokines, and serum 25 hydroxyvitamin D [25(OH)D] in patients with initial-onset childhood SLE.

Methods

A total of 82 children aged <18 years with initial-onset SLE were included, as well as 60 healthy subjects during the same period at the Pediatrics Department of the Second Hospital of Hebei Medical University. The chemiluminescence method was performed to detect serum 25(OH)D levels. Flow cytometry was used to evaluate Treg and Th17 cells. An enzyme-linked immunosorbent assay kit was used to evaluate plasma interleukin (IL)-23, IL-17, IL-10, IL-6, and tumor necrosis factor alpha (TNF-α) concentrations.

Result

The serum 25(OH)D levels in patients with initial-onset childhood SLE were significantly lower than those in the healthy controls. The proportion of lupus nephritis (LN) was higher in the vitamin D insufficiency group (71.4%) compared with the vitamin D sufficiency group (30.3%) (p < 0.05). The SLE disease activity index (SLEDAI) was higher in the vitamin D insufficiency group (median = 14) than that in the vitamin D sufficiency group (median = 9) (p < 0.05).The 25(OH)D level was positively correlated with the Treg ratio (r = 0.337, p = 0.002), and it was negatively correlated with the Th17 cell ratio (r = -0.370, p = 0.001). The serum 25(OH)D level had a negative correlation with IL-23 (r = -0.589, p < 0.001), IL-17(r = -0.351, p = 0.001), TNF-α (r = -0.283, p = 0.01), IL-6 (r = -0.392, p < 0.001), and IL-10 (r = -0.313, p = 0.004) levels.

Conclusion

The serum 25(OH)D levels decreased in patients with initial-onset childhood SLE. There was a negative correlation between the serum 25(OH)D levels and SLEDAI. The serum 25(OH)D levels in patients with initial-onset childhood SLE were negatively correlated with the Th17 ratio and related cytokines, while positively correlated with the Treg ratio.

Clinical and serological association of plasma 25-hydroxyvitamin D (25(OH)D) levels in lupus and the short-term effects of oral vitamin D supplementation

BACKGROUND AND OBJECTIVES

Data on the association of vitamin D levels and clinical phenotype and disease activity in systemic lupus erythematosus (SLE) is controversial. Further, the optimal dose of oral vitamin D supplementation in SLE is not clear. Thus, the present study was designed to determine the association of plasma vitamin D levels with clinical phenotype, disease variables and serology in a large, cohort of SLE from South Asia and to evaluate the short-term effect of two different dosage regimens of oral vitamin D supplementation on disease flares and plasma vitamin D levels.

METHODS

This is a two-phase study. Phase I was a cross-sectional analytical study of patients from north (26.85° N) and south India (11.94° N). Plasma 25-hydroxyvitamin-D(25(OH)D) was measured, and its association with demography, serology, disease activity, Galectin-9 and CXCL-10 was analysed. In phase II, patients with SLEDAI-2KG < 10 and on stable immunosuppression were randomised to receive either high dose (weekly 60,000 U*5, followed by 60,000 U monthly) or routine dose (30,000 U monthly) oral vitamin D. Outcomes were assessed at 6 months RESULTS: Phase I included 702 patients with a mean age of 29.46 + 10.7 years. The median plasma vitamin D was 22.83 (13.8-31.8) ng/ml. Deficiency (< 20 ng/ml) was seen in 41.5% of patients. Patients from South India had higher vitamin D levels (27.06 ± 20.21 ng/dl) as compared to North India (17.15 ± 16.07 ng/ml) (p < 0.01). Univariate analyses demonstrated weak negative correlation of vitamin D with SLEDAI2K and positive correlation with age. Galactin-9 had modest correlation with SLEDAI2K but not with vitamin D levels. On multiple linear regression, centre of recruitment (β = 4.37) and age (β = 0.18) predicted (p < 0.05) plasma vitamin D levels. In the phase II, 91 randomised to 2 groups completed 6 months. Median change in plasma vitamin D levels was more in high dose (9.5 versus 2.6 ng/ml; p = 0.04). There were 14 SLE flares and six minor adverse events which were equal across both groups.

CONCLUSION

Vitamin D deficiency is common in SLE. Geographical location of residence is the major determinant rather than the disease activity. The IFN regulated proteins reflect disease activity independent of vitamin D levels. High-dose oral vitamin D supplementation seems safe and more effective in improving vitamin D levels in SLE.

TRIAL REGISTRATION

The second phase of this study was a registered randomised controlled trial CTRI/2019/06/019658 [registered on: 14/06/2019].

The in vitro effects of vitamin 1, 25(OH) 2 D3 on expression of cytokines: In new-onset systemic lupus erythematosus patients

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease affecting a variety of factors in the immune system. Awareness of the role of cytokines in SLE has led to new clinical perspectives in its pathogenesis; therefore, the aim of this study was to investigate the effect of vitamin 1, 25(OH) 2 D3 (D3) on the expression of IL-2, IL-4, IL-5, IL-10, and IFN-γ cytokines in patients with lupus.

METHODS

A total of 65 new-onset SLE patients were enrolled in the study. After peripheral blood mononuclear cell isolation, the lymphocytes of each patient were divided into two groups, one treated with a concentration of 50 μmol vitamin D3 (test) and the other untreated with vitamin D3 (control), were cultured. After 24 hours, the cultured cells were collected and the expressions of IL-2, IL-4, IL-5, IL-10, and IFN-γ genes were analyzed by RT-qPCR.

RESULTS

It was observed that vitamin D3 reduced expression of IFN-γ, IL-4, IL-5, and IL-10 genes by 73, 50, 37, and 29%, respectively, and increased IL-2 gene expression by 31% (p ≤ 0.05).

CONCLUSION

With different patterns of cytokine changes in patients with lupus in different studies, it seems that the pattern of cytokine changes is largely dependent on the phase of the disease and with this study it can be concluded that vitamin D3 administration at the time of diagnosis and in the early stages and before starting treatment have different effects from its administration in the acute stage of the disease, which requires further studies to prove. It seems that in patients with systemic lupus erythematosus, vitamin D should be administered taking into account the phase of the disease.

Vitamin D Supplementation: Association With Serum Cytokines in Pediatric Hematopoietic Stem Cell Transplantation

Vitamin D deficiency is prevalent in pediatric patients presenting for hematopoietic stem cell transplantation (HSCT) and has been linked to poor clinical outcomes. Using the data from a randomized control trial, in this paper we explore the effects of vitamin D supplementation on circulating cytokine levels during pediatric HSCT (www.clinicaltrials.gov as NCT03176849). A total of 41 children, 20 received Stoss therapy and 21 children received standard of care vitamin D supplementation. Levels of 25(OH)D and 20 cytokines were assessed at baseline and day +30. Significantly (P < 0.05) higher levels of mostly proinflammatory cytokines, FGF, GCSF, TNFα, IL-2, IL-6, IP10 were detected pre-transplant for patients with low compared to those with normal vitamin D levels. In sex stratified models that compare changes in cytokines between Stoss vs. standard of care, females in the Stoss group show greater changes in mostly pro -inflammatory cytokines- IP-10 (P = 0.0047), MIG (P = 0.009), and RANTES (P = 0.0047), IL-2R (P = 0.07) and IL-6(P = 0.069). Despite a small sample size, these findings suggest vitamin D deficiency affects the pre-transplant cytokine milieu and higher doses of vitamin D (Stoss therapy) appears to influence proinflammatory cytokine responses in a sex specific manner during pediatric HSCT. Larger clinical trials are warranted to validate these results.

Circulating IL-17 Level Is Positively Associated with Disease Activity in Patients with Systemic Lupus Erythematosus: A Systematic Review and Meta-Analysis

Previous studies on the relationship between the circulating level of interleukin-17 (IL-17) and disease activity in systemic lupus erythematosus (SLE) were contradictory. This study is aimed at quantitatively assessing the correlation between the circulating IL-17 level and disease activity in SLE patients. A systematic search for related literature was conducted via PubMed, Web of Science, EMBASE, and Cochrane Library (up to January 26, 2021). The relationship between circulating IL-17 levels and SLE activity was evaluated using Fisher's z value, which was then converted to r. The standardized mean difference (SMD) and its 95% confidence interval (CI) were used to describe the difference between the circulating IL-17 level in patients with active and inactive SLE. STATA 16.0 was used to perform statistical analysis. Random-effects model was performed to synthesize data. Twenty-six studies involving 1,560 SLE patients were included in this review. The pooled r value was 0.38 (95% CI: 0.25-0.50; I² = 83.8%, P < 0.001) between the SLE activity and circulating level of IL-17. Patients with active SLE had higher level of circulating IL-17 than that of inactive (pooled SMD = 0.95, 95% CI: 0.38-1.53; I² = 90.5%, P < 0.001). The subgroup analysis suggested that the region and detection method of circulating IL-17 might not be a source of heterogeneity. No significant publication bias was found. In summary, circulating IL-17 level has a low positive relationship with SLE activity. It is necessary to carefully consider the use of circulating IL-17 as a biomarker of the disease activity in SLE patients. The relationship between the circulating level of IL-17 and SLE activity should be further confirmed in randomized controlled studies.