Vitamin D receptor gene BsmI polymorphism B allele, but not BB genotype, is associated with systemic lupus erythematosus in a Han Chinese population

Biomaterial-based combinatorial approach of aescin-comprised zein-coated gelatin nanoparticles alleviates synovial inflammation in experimental inflammatory arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that mostly affects joints. Although RA therapy has made significant progress, difficulties including extensive medication metabolism and its quick clearance result in its inadequate bioavailability. The anti-inflammatory effect of zein was reported with other medications, but it has certain limitations. There are reports on the anti-oxidant and anti-inflammatory effect of aescin, which exhibits low bioavailability for the treatment of rheumatoid arthritis. Also, the combinatorial effect of zein with other effective drug delivery systems is still under investigation for the treatment of experimental collagen-induced rheumatoid arthritis. The focus of this study was to formulate and define the characteristics of zein-coated gelatin nanoparticles encapsulated with aescin (Ze@Aes-GNPs) and to assess and contrast the therapeutic effectiveness of Ze@Aes-GNPs towards collagen-induced RA in Wistar rats. Nanoprecipitation and the layer-by-layer coating process were used to fabricate Ze@Aes-GNPs and their hydrodynamic diameter was determined to be 182 nm. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to further validate the size, shape, and surface morphology of Ze@Aes-GNPs. When tested against foreskin fibroblasts (BJ), these nanoparticles demonstrated significantly high cytocompatibility. Both Aes and Ze@Aes-GNPs were effective in treating arthritis, as shown by the decreased edoema, erythema, and swelling of the joints, between which Ze@Aes-GNPs were more effective. Further, it was demonstrated that Aes and Ze@Aes-GNPs reduced the levels of oxidative stress (articular elastase, lipid peroxidation, catalase, superoxide dismutase and nitric oxide) and inflammatory indicators (TNF-α, IL-1β and myeloperoxidase). The histopathology findings further demonstrated that Ze@Aes-GNPs considerably reduced the infiltration of inflammatory cells at the ankle joint cartilage compared to Aes. Additionally, immunohistochemistry examination showed that treatment with Ze@Aes-GNPs suppressed the expression of pro-inflammatory markers (COX-2 and IL-6) while increasing the expression of SOD1. In summary, the experiments indicated that Aes and Ze@Aes-GNPs lowered the severity of arthritis, and critically, Ze@Aes-GNPs showed better effectiveness in comparison to Aes. This suppression of oxidative stress and inflammation was likely driven by Aes and Ze@Aes-GNPs.

The impact of genetic variants related to vitamin D and autoimmunity: A systematic review

Over the past few years, there has been a notable increment in scientific literature aimed at unraveling the genetic foundations of vitamin D signaling and its implications for susceptibility to autoimmunity, however, most of them address isolated diseases. Here, we conducted a systematic review of genetic variants related to vitamin D and autoimmune diseases and we discussed the current landscape of susceptibility and outcomes. Of 65 studies analyzed, most variants cited are in vitamin D binding protein (VDBP; rs2282679 GC gene), 25-hydroxylase (rs10751657 CYP2R1), 1α-hydroxylase (rs10877012, CYP27B1) and the nuclear hormone receptor superfamily [FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236) in VDR gene]. Therefore, our findings confirmed the associations of several genetic variants of vitamin D signaling with a broad spectrum of autoimmune diseases/traits. In addition, given the low number of papers found with functional analysis, further studies to elucidate the real effect that the variants exert on Vitamin D signaling are recommended.

Differential impact of environmental factors on systemic and localized autoimmunity

The influence of environmental factors on the development of autoimmune disease is being broadly investigated to better understand the multifactorial nature of autoimmune pathogenesis and to identify potential areas of intervention. Areas of particular interest include the influence of lifestyle, nutrition, and vitamin deficiencies on autoimmunity and chronic inflammation. In this review, we discuss how particular lifestyles and dietary patterns may contribute to or modulate autoimmunity. We explored this concept through a spectrum of several autoimmune diseases including Multiple Sclerosis (MS), Systemic Lupus Erythematosus (SLE) and Alopecia Areata (AA) affecting the central nervous system, whole body, and the hair follicles, respectively. A clear commonality between the autoimmune conditions of interest here is low Vitamin D, a well-researched hormone in the context of autoimmunity with pleiotropic immunomodulatory and anti-inflammatory effects. While low levels are often correlated with disease activity and progression in MS and AA, the relationship is less clear in SLE. Despite strong associations with autoimmunity, we lack conclusive evidence which elucidates its role in contributing to pathogenesis or simply as a result of chronic inflammation. In a similar vein, other vitamins impacting the development and course of these diseases are explored in this review, and overall diet and lifestyle. Recent work exploring the effects of dietary interventions on MS showed that a balanced diet was linked to improvement in clinical parameters, comorbid conditions, and overall quality of life for patients. In patients with MS, SLE and AA, certain diets and supplements are linked to lower incidence and improved symptoms. Conversely, obesity during adolescence was linked with higher incidence of MS while in SLE it was associated with organ damage. Autoimmunity is thought to emerge from the complex interplay between environmental factors and genetic background. Although the scope of this review focuses on environmental factors, it is imperative to elaborate the interaction between genetic susceptibility and environment due to the multifactorial origin of these disease. Here, we offer a comprehensive review about the influence of recent environmental and lifestyle factors on these autoimmune diseases and potential translation into therapeutic interventions.

Vitamin D and estrogen steroid hormones and their immunogenetic roles in Infectious respiratory (TB and COVID-19) diseases

The role of steroid hormones against infectious diseases has been extensively studied. From immunomodulatory action to direct inhibition of microorganism growth, hormones D3 (VD3) and 17β-estradiol (E2), and the genetic pathways modulated by them, are key targets for a better understanding pathogenesis of infectious respiratory diseases (IRD) such as tuberculosis (TB) and the coronavirus disease-19 (COVID-19). Currently, the world faces two major public health problems, the outbreak of COVID-19, accounting for more than 6 million so far, and TB, more than 1 million deaths per year. Both, although resulting from different pathogens, the Mtb and the SARS-CoV-2, respectively, are considered serious and epidemic. TB and COVID-19 present similar infection rates between men and women, however the number of complications and deaths resulting from the two infections is higher in men when compared to women in childbearing age, which may indicate a role of the sex hormone E2 in the context of these diseases. E2 and VD3 act upon key gene pathways as important immunomodulatory players and supporting molecules in IRDs. This review summarizes the main roles of these hormones (VD3 and E2) in modulating immune and inflammatory responses and their relationship with TB and COVID-19.

Differential distribution of vitamin D receptor (VDR) gene variants and its expression in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disorder that displays an important genetic background. Vitamin D₃ (VD₃ ) through its receptor (VDR) plays an important immunomodulatory role in autoimmune misbalance, being capable of modulating immune responses. Genetic alterations in VDR gene may contribute to an altered risk in SLE development and clinical manifestations. We investigated VDR SNPs (single nucleotide polymorphisms) frequencies in 128 SLE patients and 138 healthy controls (HC) and mRNA differential expression in 29 patients and 17 HC regarding SLE susceptibility as well as clinical features. We observed that rs11168268 G allele (OR = 1.55, p = .01) and G/G genotype (OR = 2.69, p = .008) were associated with increased SLE susceptibility. The rs2248098 G allele and A/G and G/G genotypes were associated to lower SLE susceptibility (OR = 0.66, p = .01; OR = 0.46, p = .01; OR = 0.44, p = .02, respectively). Regarding clinical features, we observed lower risk for: rs11168268 A/G genotype and nephritis (OR = 0.31, p = .01); rs4760648 T/T genotype and photosensitivity (OR = 0.24, p = .02); rs1540339 T/T genotype and antibody anti-dsDNA (OR = 0.19, p = .015); rs3890733 T/T genotype and serositis (OR = 0.10, p = .01). We identified a significant downregulation in VDR expression levels when compared patients and controls overall (p = 1.04e^-7 ), in Cdx-2 A/G and G/G (p = .008 and p = .014, respectively) and in patients with nephritis (p = .016) Our results suggested that VDR SNPs influence upon SLE susceptibility and in particular clinical features, acting on mRNA expression in SLE patients overall and the ones with nephritis.

Vitamin D Status, Bone Mineral Density, and VDR Gene Polymorphism in a Cohort of Belarusian Postmenopausal Women

Vitamin D plays an important role in bone metabolism and is important for the prevention of multifactorial pathologies, including osteoporosis (OP). The biological action of vitamin is realized through its receptor, which is coded by the VDR gene. VDR gene polymorphism can influence individual predisposition to OP and response to vitamin D supplementation. The aim of this work was to reveal the effects of VDR gene ApaI rs7975232, BsmI rs1544410, TaqI rs731236, FokI rs2228570, and Cdx2 rs11568820 variants on bone mineral density (BMD), 25-hydroxyvitamin D level, and OP risk in Belarusian women. Methods. The case group included 355 women with postmenopausal OP, and the control group comprised 247 women who met the inclusion criteria. TaqMan genotyping assay was used to determine VDR gene variants. Results. Rs7975232 A/A, rs1544410 T/T, and rs731236 G/G single variants and their A-T-G haplotype showed a significant association with increased OP risk (for A-T-G, OR = 1.8, p = 0.0001) and decreased BMD (A-T-G, −0.09 g/cm², p = 0.0001). The rs11568820 A-allele showed a protective effect on BMD (+0.22 g/cm², p = 0.027). A significant dose effect with 25(OH)D was found for rs1544410, rs731236, and rs11568820 genotypes. Rs731236 A/A was associated with the 25(OH)D deficiency state. Conclusion. Our novel data on the relationship between VDR gene variants and BMD, 25(OH)D level, and OP risk highlights the importance of genetic markers for personalized medicine strategy.

Vitamin D and Glomerulonephritis

Vitamin D presents a plethora of different functions that go beyond its role in skeletal homeostasis. It is an efficient endocrine regulator of the Renin–Angiotensin–Aldosterone System (RAAS) and erythropoiesis, exerts immunomodulatory effects, reduces the cardiovascular events and all-cause mortality. In Chronic Kidney Disease (CKD) patients, Vitamin D function is impaired; the renal hydrolyzation of its inactive form by the action of 1α-hydroxylase declines at the same pace of reduced nephron mass. Moreover, Vitamin D major carrier, the D-binding protein (DBP), is less represented due to Nephrotic Syndrome (NS), proteinuria, and the alteration of the cubilin–megalin–amnionless receptor complex in the renal proximal tubule. In Glomerulonephritis (GN), Vitamin D supplementation demonstrated to significantly reduce proteinuria and to slow kidney disease progression. It also has potent antiproliferative and immunomodulating functions, contributing to the inhibitions of kidney inflammation. Vitamin D preserves the structural integrity of the slit diaphragm guaranteeing protective effects on podocytes. Activated Vitamin D has been demonstrated to potentiate the antiproteinuric effect of RAAS inhibitors in IgA nephropathy and Lupus Nephritis, enforcing its role in the treatment of glomerulonephritis: calcitriol treatment, through Vitamin D receptor (VDR) action, can regulate the heparanase promoter activity and modulate the urokinase receptor (uPAR), guaranteeing podocyte preservation. It also controls the podocyte distribution by modulating mRNA synthesis and protein expression of nephrin and podocin. Maxalcalcitol is another promising alternative: it has about 1/600 affinity to vitamin D binding protein (DBP), compared to Calcitriol, overcoming the risk of hypercalcemia, hyperphosphatemia and calcifications, and it circulates principally in unbound form with easier availability for target tissues. Doxercalciferol, as well as paricalcitol, showed a lower incidence of hypercalcemia and hypercalciuria than Calcitriol. Paricalcitol demonstrated a significant role in suppressing RAAS genes expression: it significantly decreases angiotensinogen, renin, renin receptors, and vascular endothelial growth factor (VEGF) mRNA levels, thus reducing proteinuria and renal damage. The purpose of this article is to establish the Vitamin D role on immunomodulation, inflammatory and autoimmune processes in GN.

Adaptation and co-adaptation of skin pigmentation and vitamin D genes in native Americans

We carried out an exhaustive review regarding human skin color variation and how much it may be related to vitamin D metabolism and other photosensitive molecules. We discuss evolutionary contexts that modulate this variability and hypotheses postulated to explain them; for example, a small amount of melanin in the skin facilitates vitamin D production, making it advantageous to have fair skin in an environment with little radiation incidence. In contrast, more melanin protects folate from degradation in an environment with a high incidence of radiation. Some Native American populations have a skin color at odds with what would be expected for the amount of radiation in the environment in which they live, a finding challenging the so-called "vitamin D-folate hypothesis." Since food is also a source of vitamin D, dietary habits should also be considered. Here we argue that a gene network approach provides tools to explain this phenomenon since it indicates potential alleles co-evolving in a compensatory way. We identified alleles of the vitamin D metabolism and pigmentation pathways segregated together, but in different proportions, in agriculturalists and hunter-gatherers. Finally, we highlight how an evolutionary approach can be useful to understand current topics of medical interest.

Vitamin D, autoimmunity and immune-related adverse events of immune checkpoint inhibitors

In addition to its quintessential role in bone homeostasis, vitamin D also plays an important role in regulating the immune system. As such, many studies have demonstrated the therapeutic benefit of vitamin D in treating autoimmune diseases. This immunomodulatory activity of vitamin D has recently attracted more attention due to the rapid development of immunotherapies for cancers, including melanoma. Patients on cancer immunotherapies can suffer from immune-related adverse events (irAEs), which can involve any organ system and range from common dermatological reactions to extremely severe cases of fatal myocarditis in metastatic melanoma patients. Since there are currently no effective approaches to predict or prevent irAEs, it is attractive to potentially leverage the intriguing immunomodulatory effects of vitamin D within this context. This review will discuss recent research investigating the possibility of using vitamin D to alleviate autoimmunity and irAEs with the hope of improving outcomes for patients on cancer immunotherapies, especially within the context of dermatology.

Variants rs1544410 and rs2228570 of the vitamin D receptor gene and glycemic levels in adolescents from Northeast Brazil

Introduction

Objective: to verify the association of serum concentrations of 25-hydroxyvitamin D and glycemic levels with the genetic variants rs1544410 and rs2228570 of the VDR gene in adolescents from the Northeast region of Brazil. Materials and methods: a cross-sectional epidemiological study with 208 adolescents from public schools in the city of João Pessoa (Paraíba, Brazil) between 15 and 19 years of age. Blood samples were collected for DNA extraction and analysis of polymorphisms rs1544410 and rs2228570, as well as biochemical analyses (25-hydroxyvitamin D, parathyroid hormone, calcium and glycemia). Results: the mean age was 17.7 (± 1.14) years. Half of adolescents had sufficient serum levels of 25-hydroxyvitamin D and the other half had insufficient/deficient vitamin. The most frequent genotypic distribution was bb and Ff and of lesser frequency BB and ff. There was a significant relationship between the genotypes of rs1544410 and glycemia values (p = 0.049) in the relationships between the genotypes BBxbb (p = 0.012) and Bbxbb (p = 0.037); (p = 0.036, OR = 2.15, 95% CI = 1.05-4.41), and in the BB+Bb group analysis when compared to the bb (p = 0.025, OR = 1.89, 95% CI = 1.08-3.29) presented higher risk of glycemia above the median. On the other hand, when Bb+bb was analyzed in relation to BB, adolescents had a greater chance of blood glucose below the median (p = 0.025, OR = 0.66, CI = 0.47-0.95). Conclusion: this study showed a significant relation of glycemia with the distribution of rs1544410 polymorphism genotypes.

Vitamin D Receptor rs2228570 and rs731236 Polymorphisms are Susceptible Factors for Systemic Lupus Erythematosus

Background:

The Vitamin D receptor (VDR) polymorphisms are the candidate genetic variants for susceptibility to different disease including autoimmune disorders. In the present study, we aimed to assess the association between VDR polymorphisms and systemic lupus erythematosus (SLE) susceptibility in Southeast Iranian population.

Materials and Methods:

One hundred and twenty-seven patients with SLE and 139 controls were genotyped for VDR rs2228570, rs731236, and rs7975232 polymorphisms using polymerase chain reaction-restriction fragment length polymorphism method.

Results:

The VDR rs2228570 polymorphism was associated with higher risk of SLE in codominant, dominant, and overdominant models. Moreover, higher risk of SLE was observed in individuals with VDR rs731236 polymorphism in codominant, dominant, overdominant, and allelic models. The tAf haplotype of rs731236/rs7975232/rs2228570 polymorphisms was associated with higher risk of SLE.

Conclusion:

In conclusion, VDR rs2228570 and rs731236 polymorphisms and tAf haplotype were associated with SLE risk.

Vitamin D receptor expression in peripheral blood mononuclear cells is inversely associated with disease activity and inflammation in lupus patients

OBJECTIVE

Systemic lupus erythematosus (SLE) is characterized by uncontrolled production of pro-inflammatory cytokines. Vitamin D receptor (VDR) has potent anti-inflammatory activities. The aim of this study was to examine the correlation between VDR expression and inflammation and disease activity in patients with SLE.

METHODS

Ninety-five SLE patients were recruited and divided into two groups, active and inactive, according to their SLE disease activity index (SLEDAI)-2 K, and 40 healthy individuals served as controls. The expression of VDR and NF-κB p65 in peripheral blood mononuclear cells (PBMCs) was determined by quantitative RT-PCR and Western blotting. VDR expression was correlated with inflammatory and diseases parameters in SLE patients. VDR regulation was also studied in THP-1 and Jurkat cell lines.

RESULTS

PBMC VDR expression was downregulated in SLE patients, especially in the active SLE group. VDR mRNA levels were negatively correlated with SLEDAI-2 K (r = - 0.348, P = 0.001), Systemic Lupus International Collaborating Clinics (SLICC) renal activity scores (r = - 0.346, P = 0.014), and proteinuria (r = - 0.309, P = 0.002) and positively associated with serum complement C3 levels (r = 0.316, P = 0.002). Multiple stepwise regression analysis indicated that PBMC VDR downregulation was an independent risk factor for SLEDAI-2 K. VDR levels were also negatively correlated with NF-κB p65 (r = - 0.339, P = 0.001), TNF-α (r = - 0.268, P = 0.009), and IL-6 (r = - 0.313, P = 0.002) levels. In monocyte and T lymphocyte cell lines, TNF-α suppressed VDR expression, whereas 1,25-dihydroxyvitamin D blocked TNF-α-induced VDR downregulation.

CONCLUSION

PBMC VDR expression is inversely associated with disease activity and inflammation in SLE patients, and VDR downregulation is likely driven by inflammation.

Oxidative stress and vitamin D receptor BsmI gene polymorphism in Egyptian children with systemic lupus erythematosus: a single center study

Systemic lupus erythematosus (SLE) is an autoimmune disease with unknown exact etiology. Vitamin D receptor gene ( VDR) and oxidative stress play important roles in the pathogenesis of SLE. Here we investigated the genotypes and allelic frequencies of VDR BsmI polymorphism as well as their relationship with oxidative stress markers in Egyptian SLE children. We conducted a cross-sectional comparative study at Mansoura University Children's Hospital, Egypt from 2014 to 2018 including 100 SLE children and 100 controls. We investigated both groups for VDR BsmI polymorphism using polymerase chain reaction. Oxidative stress was assessed using malondialdehyde, glutathione S-transferase, superoxide dismutase, catalase and total antioxidant capacity. BB genotype frequency was found to be significantly higher in the SLE group ( p = 0.04, odds ratio (95% confidence interval) = 2.5 (1.01–5.9)). However, VDR B allele and b allele showed insignificant differences between SLE patients and controls ( p = 0.36, odds ratio (95% confidence interval) = 1.2 (0.8–1.8)). Lower levels of glutathione S-transferase, superoxide dismutase and total antioxidant capacity were found in the SLE group with statistically significant differences as regards glutathione S-transferase and superoxide dismutase ( p < 0.001). Serum malondialdehyde and catalase levels were significantly higher in the SLE group ( p < 0.001). No significant differences were found between VDR BsmI polymorphism (genotypes and alleles) and oxidative stress markers in the SLE group. In conclusion, BB genotype of VDR BsmI polymorphism is associated with an increased risk of SLE among Egyptian children. Oxidative stress may contribute in pathogenesis of SLE but is not associated with VDR BsmI polymorphism.

Expression of vitamin D receptor in renal tissue of lupus nephritis and its association with renal injury activity

Objective

Vitamin D receptor (VDR) has potent anti-inflammatory activities. VDR gene polymorphism has been linked with systemic lupus erythematosus (SLE). However, its expression in the kidney has not been evaluated. This study aimed to investigate the relationship between VDR expression and renal pathology as well as clinical manifestations in lupus nephritis (LN).

Methods

A total of 20 renal biopsy specimens from 35 patients with LN were classified according to the International Society of Nephrology/Renal Pathology Society 2003 LN-type standards pathological type, and the activity index and chronicity index were determined. Five normal renal tissue samples were obtained from surrounding areas distal to nephronophthisis or renal tumors (>2 cm). The expression of VDR was assessed by immunohistochemistry. The relationships between VDR expression and histological injury index, proteinuria and Systemic Lupus International Collaborating Clinics (SLICC) renal activity scores were analyzed.

Results

As compared to the control group, the expression of VDR in the LN group was lower ( p < 0.001) and negatively correlated with activity index (r = –0.548, p = 0.012) but not with chronicity index (r = –0.277, p = 0.236). The expression of VDR in renal tissue was also associated with SLICC renal activity scores (r = –0.470, p = 0.037).

Conclusion

The down-regulation of VDR expression in renal tissues of LN patients was negatively correlated with renal activity and injury severity.

Vitamin D receptor ApaI, TaqI, BsmI, and FokI polymorphisms and psoriasis susceptibility: an updated meta-analysis

BACKGROUND

Vitamin D is considered a regulator of the immune system, and its polymorphisms have been associated with psoriasis in some but not all reports.

AIM

To explore whether vitamin D receptor (VDR) polymorphisms are associated with susceptibility to psoriasis.

METHODS

Meta-analyses were conducted to determine the associations between psoriasis and the VDR ApaI, TaqI, BsmI and FokI polymorphisms in all participants, and stratified by ethnic group.

RESULTS

In total, 16 studies on VDR polymorphisms and psoriasis were included in this meta-analysis, which involved 2086 patients and 2182 controls. The meta-analysis indicated an association between psoriasis and the VDR TaqI TT genotype in Caucasian (OR = 1.29, 95% CI = 1.00-1.66, P < 0.05), but not in Asian (OR = 1.32, 95% CI = 0.89-1.96, P = 0.16) populations. However, no association was found between psoriasis and the VDR TaqI polymorphism using dominant, allele contrast or homozygous contrast models. No association was found between psoriasis and either the VDR ApaI, BsmI or FokI polymorphisms by meta-analyses of the allele contrast, recessive, or dominant models or homozygous contrast models in the overall, Caucasian or Asian populations.

CONCLUSION

This meta-analysis showed that polymorphisms in VDR ApaI, BsmI and FokI are not associated with psoriasis susceptibility in overall, Caucasian or Asian populations. However, the VDR TaqI polymorphism is associated with psoriasis susceptibility in Caucasian populations.

Association of SNP-SNP Interactions Between RANKL, OPG, CHI3L1, and VDR Genes With Breast Cancer Risk in Egyptian Women

BACKGROUND

Genetic susceptibility for breast cancer (BC) is still poorly understood. A combination of multiple low-penetrant alleles of cancer-related genes and gene-gene interactions (epistasis) contributes to BC risk. Genetic variants in receptor activator of nuclear factor κB ligand (RANKL), osteoprotegerin (OPG), chitinase-3-like protein 1 (CHI3L1), and vitamin D receptor (VDR) genes are implicated in breast carcinogenesis; however, the influence of their epistatic effects on BC susceptibility has not yet been studied. We investigated the association of single nucleotide polymorphism (SNP)-SNP interactions and haplotypes of 6 SNPs in these 4 genes with the genetic predisposition of BC in Egyptian women.

PATIENTS AND METHODS

Data of 115 BC patients and 120 cancer-free controls were studied. Association tests were conducted using logistic regression models.

RESULTS

Individual SNPs showed weak statistical significance with BC susceptibility. The interactions between RANKL-rs9533156 and OPG-rs2073618; OPG-rs2073618 with CHI3L1-rs4950928, VDR-rs2228570 and VDR-rs1544410; OPG-rs2073617 and VDR-rs1544410; VDR-rs2228570 and VDR-rs1544410 were strongly associated with increased BC risk after adjustment for multiple comparisons. No SNPs were in strong linkage disequilibrium. The TCTCTG-rs9533156-rs2073618-rs2073617-rs4950928-rs2228570-rs1544410 haplotype was significantly associated with increased BC risk (adjusted odds ratio = 8.33; 95% confidence interval, 1.32-52.46; P = .025) compared with controls. TCCCTG haplotype stratified BC patients according to estrogen receptor/progesterone receptor status. TCTCTA was positively associated, and TCTCTG and TGTCTG haplotypes inversely correlated with bone metastasis. Bioinformatic analysis revealed 13 proteins commonly interacting with our 4 genes; the most significant was signal transducer and activator of transcription 5B.

CONCLUSION

Our results suggested that a stronger combined effect of SNPs in RANKL, OPG, CHI3L1, and VDR genes via gene-gene interaction may help predict BC risk and prognosis.

A population association study of vitamin D receptor gene polymorphisms and haplotypes with the risk of systemic lupus erythematosus in a Chinese population

The aim of the study is to investigate the association of vitamin D receptor (VDR) gene polymorphism, additional gene-gene interaction, and haplotype combination with systemic lupus erythematosus (SLE) risk. Pairwise linkage disequilibrium (LD) analysis was conducted using SNPstats. The association between four SNPs within VDR gene and SLE risk was investigated by logistic regression. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the interaction among four SNPs. Four SNPs within VDR gene were selected for genotyping in this study, including rs2228570, rs1544410, rs7975232, and rs731236. The T allele of rs2228570 and the G allele of the rs1544410 were associated with increased MM risk, adjusted ORs (95%CI) were 1.61(1.25-2.11) and 1.78 (1.34-2.23), respectively. GMDR analysis suggested a significant two-locus model (P = 0.0010) involving rs1544410 and rs2228570, and in this model, the cross-validation consistency was 10/10, and the testing accuracy was 62.70%. The haplotype analysis indicated that the most common haplotype was rs1544410-A and rs7975232-G haplotype, the frequencies of which were 0.4701 and 0.5467 in case and control group. Haplotype containing the rs1544410-G and rs7975232-T alleles were associated with increased SLE risk, OR (95%CI) = 2.08 (1.47-2.72), P < 0.001. We found that rs2228570 and rs1544410 within VDR gene, their interaction and haplotype containing the rs1544410-G and rs7975232-T alleles were all associated with increased SLE risk.

Vitamin D receptor FokI, TaqI, and ApaI polymorphisms and susceptibility to systemic lupus erythematosus: an updated meta-analysis

This study aimed to explore whether vitamin D receptor (VDR) polymorphisms are associated with susceptibility to systemic lupus erythematosus (SLE). Meta-analyses were conducted to determine the associations between the VDR FokI, TaqI, and ApaI polymorphisms and SLE in all subjects and each ethnic group. A total of 12 studies were considered in the meta-analysis, which involved 1974 patients and 2506 controls. Meta-analysis of the VDR FokI polymorphism showed no association between SLE and the FokI F allele in all study subjects (OR = 1.047, 95% CI = 0.781-1.403, p = 0.758). However, the meta-analysis showed a significant association between SLE and the VDR FokI F allele in the Arab population (OR = 1.721, 95% CI = 1.417-2.088, p < 0.001). Analysis using the recessive and dominant models and homozygote contrast showed the same pattern for the VDR FokI F allele in Europeans, Asians, and Arabs. This meta-analysis showed that polymorphisms in VDR FokI, TaqI, and ApaI are not associated with SLE susceptibility in overall, European and Asian populations. However, the VDR FokI polymorphism is associated with SLE susceptibility in the Arab population.

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 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.

Beta carotene-loaded zein nanoparticles to improve the biopharmaceutical attributes and to abolish the toxicity of methotrexate: a preclinical study for breast cancer

Beta carotene (βC) loaded nanoparticles of zein (βC-NPs) were developed using modified phase separation technique. βC-NPs were prepared using different zein concentration and optimized formulation was selected on the basis of micromeritics properties and entrapment efficiency. Further, βC-NPs were evaluated for in vitro release, in vitro cell-survival, cellular localization and apoptosis induced in MCF-7 cells. The combined effect of the βC and its nanoparticulate counterpart with MTX was evaluated thereafter for cytotoxicity and apoptotic activity in MCF-7 cells. In comparison to free βC, the βC-NPs demonstrated noteworthy improvement in various biopharmaceutical attributes viz C_max (∼2.3-folds), AUC_total (2.7-folds), t_1/2 (∼1.5 folds) and MRT (∼1.5 folds), further indicating the remarkable increment in oral bioavailability of βC after incorporation in zein nanoparticles. The anti-tumour potential of prepared βC-NPs and effects of free βC and βC-NPs were investigated upon anticancer efficacy of methotrexate (MTX) in experimentally induced breast cancer rat model. Protective role of βC on MTX-associated hepatic toxicity in wistar rats was also determined using haematological and histopathological approaches. In a nutshell, zein nanoparticles improved the cellular uptake, cytotoxicity and exhibited enhanced oral biopharmaceutical performance of βC. This combination regimen could also be promising platform to facilitate the therapeutic benefits of anticancer agents.

Relationship of vitamin D receptor gene polymorphisms in Helicobacter pylori gastric patients

Purpose

The present study aimed to investigate the association between the human VDR gene and Helicobacter pylori infection.

Patients and methods

A cross-sectional study was conducted on 208 adult patients with upper gastrointestinal symptoms. Gastric biopsy specimens were obtained from each patient for molecular DNA and histological examination. Patients were genotyped for VDR gene polymorphisms using polymerase chain reaction and restriction fragment length polymorphism analysis.

Results

The allelic and genotypic distribution analyses of the FokI, ApaI and TaqI polymorphisms of the VDR gene did not show distribution differences between H. pylori-positive and -negative groups. The genotype distribution observed for polymorphism BsmI deviated significantly from what was expected in a Hardy–Weinberg equilibrium test in the H. pylori-positive group (χ²=29.048, p<0.001). The distribution of BsmI genotypes differed significantly between the H. pylori-negative and H. pylori-positive groups (p=0.0034), where the frequency of the bb genotype increased among H. pylori-positive individuals compared with those without infection (63.25% versus 50.55%, respectively). Conversely, the H. pylori-negative group showed a Bb frequency that was 20.27% higher than in the infected group.

Conclusion

We identified a possible association between the BsmI polymorphism and infection by H. pylori. However, further research is required to clarify this relationship.

Vitamin D Receptor: A Novel Therapeutic Target for Kidney Diseases

BACKGROUND

Kidney disease is a serious problem that adversely affects human health, but critical knowledge is lacking on how to effectively treat established chronic kidney disease. Mounting evidence from animal and clinical studies has suggested that Vitamin D Receptor (VDR) activation has beneficial effects on various renal diseases.

METHODS

A structured search of published research literature regarding VDR structure and function, VDR in various renal diseases (e.g., IgA nephropathy, idiopathic nephrotic syndrome, renal cell carcinoma, diabetic nephropathy, lupus nephritis) and therapies targeting VDR was performed for several databases.

RESULT

Included in this study are the results from 177 published research articles. Evidence from these papers indicates that VDR activation is involved in the protection against renal injury in kidney diseases by a variety of mechanisms, including suppression of RAS activation, anti-inflammation, inhibiting renal fibrogenesis, restoring mitochondrial function, suppression of autoimmunity and renal cell apoptosis.

CONCLUSION

VDR offers an attractive druggable target for renal diseases. Increasing our understanding of VDR in the kidney is a fertile area of research and may provide effective weapons in the fight against kidney diseases.

Vitamin D and VDR in cancer cachexia and muscle regeneration

Low circulating levels of vitamin D were associated with decreased muscle strength and physical performance. Along this line, the present study was aimed to investigate: i) the therapeutic potential of vitamin D in cancer-induced muscle wasting; ii) the mechanisms by which vitamin D affects muscle phenotype in tumor-bearing animals.

Rats bearing the AH130 hepatoma showed decreased circulating vitamin D compared to control rats, while muscle vitamin D receptor (VDR) mRNA was up-regulated. Both circulating vitamin D and muscle VDR expression increased after vitamin D administration, without exerting appreciable effects on body weight and muscle mass.

The effects of vitamin D on muscle cells were studied in C2C12 myocytes. Vitamin D-treated myoblasts did not differentiate properly, fusing only partially and forming multinucleated structures with aberrant shape and low myosin heavy chain content. Vitamin D treatment resulted in VDR overexpression and myogenin down-regulation. Silencing VDR expression in C2C12 cultures abrogated the inhibition of differentiation exerted by vitamin D treatment.

These data suggest that VDR overexpression in tumor-bearing animals contributes to muscle wasting by impairing muscle regenerative program. In this regard, attention should be paid when considering vitamin D supplementation to patients affected by chronic pathologies where muscle regeneration may be involved.

Vitamin D receptor FokI, BsmI, and TaqI polymorphisms and susceptibility to rheumatoid arthritis : A meta-analysis

OBJECTIVE

The aim of this study was to explore whether vitamin D receptor (VDR) polymorphisms are associated with susceptibility to rheumatoid arthritis (RA).

METHODS

Meta-analyses were conducted on the associations between the VDR FokI, BsmI, and TaqI polymorphisms and RA.

RESULTS

A total of seven studies were considered in the meta-analysis, involving a total of 923 patients and 912 controls. Meta-analysis of the VDR FokI polymorphism showed no association between RA and the F allele in the entire studied cohort (odds ratio, OR = 1.1740, 95 % confidence interval, CI = 0.994-1.387, p = 0.059). However, stratification by ethnicity revealed a significant association between the F allele and RA in Europeans (OR = 1.402, 95 % CI = 1.126-1.746, p = 0.003). Furthermore, an association was found between RA and the VDR FokI polymorphism using both the dominant model and homozygote contrast. Meta-analysis revealed no association between RA and the VDR BsmI B and TaqI T polymorphisms in Europeans (OR for the B allele = 1.065, 95 % CI = 0.911-1.245, p = 0.427; OR for the T allele = 1.065, 95 % CI = 0.834-1.361, p = 0.613).

CONCLUSION

This meta-analysis suggests that the VDR FokI polymorphism is associated with susceptibility to RA in European populations.

Vitamin D receptor gene BsmI polymorphisms in Egyptian children and adolescents with systemic lupus erythematosus: A case-control study

Systemic lupus erythematosus (SLE) is a multisystemic autoimmune disease. The vitamin D receptor (VDR) gene is a candidate gene for susceptibility to autoimmune disorders. To date, only a few studies concerned the association of the VDR gene polymorphisms with childhood-onset SLE.In this study, we aimed to investigate the BsmI polymorphisms in the VDR gene, for the first time in Egyptian children and adolescents with SLE, to determine whether this polymorphism could be a marker of susceptibility to or severity of SLE and we also measured the serum level of 25-hydroxyvitamin D (25[OH] D) to assess its relation to such polymorphism.This was a case-control study including 100 patients with SLE and matched with age, sex, and ethnicity and 100 healthy controls. All subjects were genotyped for the VDR gene BsmI polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), whereas the serum 25(OH) D levels were measured by enzyme-linked immunosorbent assay method.Compared to the contros subjects, the VDR BsmI BB genotype and B allele were overrepresented among SLE patients (odda ratio [OR]: 5.5; 95% confidence interval [CI]: 1.9-15.9; P = 0.002 and OR: 1.84; 95% CI: 1.21-2.80; P = 0.003; respectively). We found a significant association between VDR BsmI BB genotype with lupus nephritis (OR: 6.8; 95% CI: 1.18-50.5; P = 0.001). However, we did not observe any significant association of studied polymorphisms with other clinical manifestations, laboratory profiles of SLE, or disease activity score. Our data revealed no association between VDR BsmI genotypes or alleles and serum 25-hydroxyvitamin D levels among studied patients with SLE (all P > 0.05).We demonstrate for the first time, to the best of our knowledge, that the VDR BsmI gene polymorphisms may contribute to susceptibility to SLE in Egyptian children and adolescents. Moreover, we found that the BB genotype constituted a risk factor for the development of nephropathy among studied patients with SLE. However, we did not find any significant association of the VDR BsmI gene variants with other clinical manifestations, laboratory profiles of SLE, disease activity index score, or serum 25-hydroxyvitamin D levels.

Associations between vitamin D receptor gene polymorphisms and ankylosing spondylitis in Chinese Han population: a case-control study

We assessed whether the vitamin D receptor gene polymorphisms (FokI, BsmI, ApaI, and TaqI) were associated with ankylosing spondylitis (AS) in a Chinese Han population. The TaqI polymorphism G allele was a risk factor in AS susceptibility.

INTRODUCTION

Previous studies have found that serum vitamin D levels are declined in patients with AS. The present study aims to evaluate the role of vitamin D receptor (VDR) gene polymorphisms in AS susceptibility in a Chinese Han population.

METHODS

Four single nucleotide polymorphisms (SNPs) in the VDR gene (FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232), and TaqI (rs731236)) were genotyped by the improved multiplex ligase detection reaction (iMLDR) method in 620 AS patients and 620 geographically and ethnically matched healthy controls. Haplotypes were constructed after linkage disequilibrium (LD) analysis.

RESULTS

Statistically significant difference was only found in the TaqI polymorphism between AS patients and controls. The TaqI polymorphism G allele was higher in AS group than that in controls (OR [95 % CI] = 1.624 [1.122-2.352], χ (2) = 6.705, P = 0.006). Linkage disequilibrium has been detected in TaqI and BsmI polymorphisms (D' = 0.87, r (2) = 0.70). Two novel haplotypes (H1: AC and H2: GT) were significantly associated with the risk of AS, and they play protective and risk roles in AS morbidity, respectively.

CONCLUSIONS

The VDR gene TaqI polymorphism G allele may be a risk factor in AS susceptibility.

Combined role of vitamin D status and CYP24A1 in the transition to systemic lupus erythematosus

OBJECTIVE

We examined whether measures of vitamin D were associated with transitioning to systemic lupus erythematosus (SLE) in individuals at risk for SLE.

METHODS

436 individuals who reported having a relative with SLE but who did not have SLE themselves were evaluated at baseline and again an average of 6.3 (±3.9) years later. Fifty-six individuals transitioned to SLE (≥4 cumulative American College of Rheumatology criteria). 25-Hydroxyvitamin D (25[OH]D) levels were measured by ELISA. Six single-nucleotide polymorphisms in four vitamin D genes were genotyped. Generalised estimating equations, adjusting for correlation within families, were used to test associations between the vitamin D variables and the outcome of transitioning to SLE.

RESULTS

Mean baseline 25[OH]D levels (p=0.42) and vitamin D supplementation (p=0.65) were not different between those who did and did not transition to SLE. Vitamin D deficiency (25[OH]D <20 ng/mL) was greater in those who transitioned compared with those who did not transition to SLE (46% vs 33%, p=0.05). The association between 25[OH]D and SLE was modified by CYP24A1 rs4809959, where for each additional minor allele increased 25[OH]D was associated with decreased SLE risk: zero minor alleles (adjusted OR: 1.03, CI 0.98 to 1.09), one minor allele (adjusted OR: 1.01, CI 0.97 to 1.05) and two minor alleles (adjusted OR: 0.91, CI 0.84 to 0.98). Similarly, vitamin D deficiency significantly increased the risk of transitioning to SLE in those with two minor alleles at rs4809959 (adjusted OR: 4.90, CI 1.33 to 18.04).

CONCLUSIONS

Vitamin D status and CYP24A1 may have a combined role in the transition to SLE in individuals at increased genetic risk for SLE.

Genetic Variants That Are Associated with Neuropsychiatric Systemic Lupus Erythematosus

OBJECTIVE

While genetic risks have been implicated in systemic lupus erythematosus (SLE), the involvement of various genotypes in neuropsychiatric SLE (NPSLE) remains uncertain. The present metaanalysis aimed to combine data from different studies and evaluate the association between each genotype and the risk of developing NPSLE.

METHODS

Studies were searched and retrieved from online databases (PubMed, EMBASE, BIOSIS, and ScienceDirect). Case-control studies were chosen if they reported genotype frequencies of the γ Fc region (FCγR) receptors II-A, III-A, and III-B; tumor necrosis factor-α (TNF-α); mannan-binding lectin (MBL); integrin alpha M (ITGAM); interleukin (IL) 1, IL-1β, and IL-6; IL-10 promoter; and vitamin D genes. The OR were used to assess the strength of this association between patients with NPSLE and SLE.

RESULTS

A total of 33 studies were considered in this metaanalysis. The results suggest that these genotypes demonstrated a significant association with NPSLE: the homozygous FCγR IIIa 158 FF genotype (OR 1.89, p = 0.03 for FF vs VV + FV), heterozygous FCγR IIIb NA1/2 genotype (OR 2.14, p = 0.03 for NA1/2 vs NA1/1; OR 1.81, p = 0.04 for NA1/2 vs NA1/1 + NA2/2), and homozygous ITGAM rs1143679 HH genotype (OR 3.39, p = 0.04 for HH vs RH; OR 3.11, p = 0.048 for HH vs RR + RH). Polymorphisms of the TNF-α, MBL2, IL-1, IL-1β, IL-6, IL-10 promoter, and vitamin D receptor genes did not show a statistically significant association with the risk of developing NPSLE (p > 0.05).

CONCLUSION

This metaanalysis indicates that polymorphisms in the pathways of immune complex clearance, such as the FcγRIIIa, FcγRIIIb, and ITGAM genotypes, are potential susceptibility genes for NPSLE.

Doxorubicin-loaded biodegradable self-assembly zein nanoparticle and its anti-cancer effect: Preparation, in vitro evaluation, and cellular uptake

Cancer is one top leading cause of the deaths worldwide. Various anticancer drugs, which can effectively kill cancer cells, have been developed in the last decade. However, the problem is still about the low therapeutic index of the drugs, which means that the effective dose of drugs will cause cytotoxicity to normal cells. A strategy based on drug nano-encapsulation is applied to achieve an effective anti-cancer therapy. In this study, we use zein, which is an amphiphilic protein, to make the anti-cancer drug nano-encapsulation. Doxorubicin (DOX), a popular anti-cancer drug, is selected as the core drug. The results show that DOX could be successfully encapsulated into zein to form spherical nanoparticles. The encapsulation efficiency and loading efficiency could reach as high as 90.06% and 15.01 mg/g, respectively. The cumulative release result showed a desired pH-responsible release behavior: DOX could be released faster in acidic buffer solutions (pH 5.0 and 6.5) than neutral one (pH 7.4). The effects of the nano-encapsulation on the anti-proliferation of HeLa cells were also examined. It indicated that, compared with free DOX, the DOX-loaded zein nanoparticles (DOX-zein-NPs) had a better effect on cancer cell killing at low DOX concentrations. We also investigated the cellular uptake of DOX-zein-NPs using confocal laser scanning microscopy (CLSM), flow cytometry, and transmission electron microscopy (TEM). And the endocytosis mechanism of DOX-zein-NPs entering into HeLa cells was studied using various endocytosis pathway inhibitors.

Impact of the polymorphism in vitamin D receptor gene BsmI and the risk of systemic lupus erythematosus: an updated meta-analysis

The etiology of system lupus erythematosus (SLE) still remains unclear, and vitamin D is associated with immune response. Although a few studies are conducted to investigate the association between polymorphism in vitamin D receptor (VDR) genes and SLE risk, their results are conflicting. Following the guideline of PRISMA, we conducted a systematic search and meta-analysis of the BsmI polymorphism rs1544410 and the risk of SLE. The pooled odds ratios (OR) and its 95 % confidential interval (CI) were calculated by using Stata Version 10 with dominant and recessive model and allele analyses. Nine studies were included in our meta-analysis with a total of 1247 SLE cases and 1687 controls. No significant association was found in both models in the overall population. Only Bb + BB genotypes showed a significantly elevated SLE risk in Asian subgroup with an OR of 3.26 (95 % CI = 1.30-8.17) while no significance was observed in Caucasian population. Notably, B allele significantly increased the SLE risk among Asian population with an OR of 2.29 (95 % CI = 1.14-4.61). No positive findings were reported in Caucasian population and in the overall analysis. In Asian population, Bb + BB genotype and B allele can significantly increase the SLE risk.

Polymorphic variants in the vitamin D pathway genes and the risk of ovarian cancer among non-carriers of BRCA1/BRCA2 mutations

Previous studies have produced inconsistent results regarding the contribution of single-nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) gene to ovarian cancer (OC) in various ethnicities. Additionally, little has been established with regard to the role of SNPs located in the retinoid X receptor α (RXRA), vitamin D-binding protein [also know as group-specific component (GC)] and VDR genes in non-carriers of the breast cancer 1/2 early onset (BRCA1/BRCA2) gene mutations. All participating individuals in the present study were evaluated for BRCA1 mutations (5382incC, C61G and 4153delA) with HybProbe assays, and for BRCA2 mutation (5946delT) using high-resolution melting (HRM) analysis. The associations of 8 SNPs located in RXRA, GC and VDR were investigated in OC patients without the BRCA1/BRCA2 mutations (n=245) and healthy controls (n=465). Genotyping of RXRA rs10881578 and rs10776909, and GC rs1155563 and rs2298849 SNPs was conducted by HRM analysis, while RXRA rs749759, GC rs7041, VDR BsmI rs1544410 and FokI rs2228570 genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism analysis. In addition, the gene-gene interactions among all tested SNPs were studied using the epistasis option in PLINK software. The lowest P-values of the trend test were identified for VDR rs1544410 and GC rs2298849 as P_trend=0.012 and P_trend=0.029, respectively. It was also found that, in the dominant inheritance model, VDR BsmI contributed to an increased risk of OC [odds ratio (OR), 1.570; 95% confidence interval (CI), 1.136-2.171; P=0.006; P_corr=0.048]. The gene-gene interaction analysis indicated a significant interaction between RXRA rs749759 and VDR FokI rs2228570 (OR for interaction, 1.687; χ²=8.278; asymptotic P-value=0.004; P_corr=0.032). In conclusion, this study demonstrated that certain VDR and RXRA SNPs may be risk factors for OC in non-carriers of BRCA1/BRCA2 mutations in the Polish population.

"Let there be light": the role of vitamin D in the immune response to vaccines

Vitamin D's non-skeletal actions, including immunomodulatory role, have been increasingly recognized. Of significance, many immune cells are able to synthesize a biologically active form of vitamin D from circulating 25-hydroxyvitamin D with subsequent intracrine actions, and the vitamin D receptor is broadly distributed. In this review, we discuss vitamin D's potent role in innate and adaptive immune responses and published studies evaluating the impact of serum vitamin D, vitamin D gene pathway polymorphisms or empiric vitamin D supplementation on vaccine immunogenicity. We highlight existing knowledge gaps and propose the steps needed to advance the science and answer the question of whether vitamin D may prove valuable as a vaccine adjuvant for certain vaccines against infectious diseases.

Association between vitamin D receptor (VDR) gene polymorphisms and systemic lupus erythematosus in Portuguese patients

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease of unknown origin, in which both genetic and environmental factors are involved. One such environmental factor is vitamin D, a vital hormone that plays a specific function in the immune system homeostasis, acting through a nuclear receptor ( VDR) expressed in all immune cells. Several polymorphisms of the gene that encodes this receptor have been described. Though inconsistently, these polymorphisms have been associated with clinical manifestations and SLE development.

The aim of this study was to determine the possible association between VDR gene polymorphisms (BsmI, ApaI, TaqI e FokI) and SLE susceptibility and severity, in a cohort of lupus patients from the north of Portugal.

A total of 170 patients (F = 155, M = 15; age = 45 ± 13.4 years) with SLE (diagnosed according the American College of Rheumatology criteria) with at least five years of disease evolution and followed in the Autoimmune Disease Clinical Immunology Unit of Centro Hospitalar do Porto were studied. Patients and 192 ethnicity-matched controls were genotyped for BsmI (rs1544410), ApaI (rs7975232), TaqI (rs731236) and FokI (rs2228570) polymorphisms by TaqMan allelic discrimination assay. Disease severity was assessed by SLICC damage score, number of affected organs, number of severe flares and pharmacological history.

SLE patients with the CT genotype of FokI polymorphism have a higher SLICC value ( p = 0.031). The same result was observed for the group of patients with the TT genotype of TaqI polymorphism ( p = 0.046). No differences were observed in VDR genotype between patients and controls. Also, we observed that the other clinical features analysed were not influenced by VDR polymorphisms.

Our study confirms a possible role of VDR gene polymorphisms in SLE. A positive association was found between VDR polymorphisms and SLE severity (chronic damage). The presence of CT genotype of FokI and TT genotype of TaqI seems to confer a worse prognosis and may constitute a risk factor for higher long-term cumulative damage in SLE patients.

Vitamin D receptor gene polymorphisms and haplotypes in Hungarian patients with idiopathic inflammatory myopathy

Idiopathic inflammatory myopathies are autoimmune diseases characterized by symmetrical proximal muscle weakness. Our aim was to identify a correlation between VDR polymorphisms or haplotypes and myositis. We studied VDR-BsmI, VDR-ApaI, VDR-TaqI, and VDR-FokI polymorphisms and haplotypes in 89 Hungarian poly-/dermatomyositis patients (69 females) and 93 controls (52 females). We did not obtain any significant differences for VDR-FokI, BsmI, ApaI, and TaqI genotypes and allele frequencies between patients with myositis and healthy individuals. There was no association of VDR polymorphisms with clinical manifestations and laboratory profiles in myositis patients. Men with myositis had a significantly different distribution of BB, Bb, and bb genotypes than female patients, control male individuals, and the entire control group. Distribution of TT, Tt, and tt genotypes was significantly different in males than in females in patient group. According to four-marker haplotype prevalence, frequencies of sixteen possible haplotypes showed significant differences between patient and control groups. The three most frequent haplotypes in patients were the fbAt, FBaT, and fbAT. Our findings may reveal that there is a significant association: Bb and Tt genotypes can be associated with myositis in the Hungarian population we studied. We underline the importance of our result in the estimated prevalence of four-marker haplotypes.

Pediatric vitiligo

Vitiligo is a disease of pigment loss. Most investigators currently consider vitiligo to be a disorder that occurs as a result of autoimmune destruction of melanocytes, supported by identification of antimelanocyte antibodies in many patients, and the presence of comorbid autoimmune disease in patients with and family members of individuals with vitiligo. One-half of vitiligo cases are of childhood onset. This article presents a current overview of pediatric vitiligo including comorbidities of general health, psychological factors, therapeutic options, and long-term health considerations.

The implication of vitamin D and autoimmunity: a comprehensive review

Historically, vitamin D has been associated with the regulation of bone metabolism. However, increasing evidence demonstrates a strong association between vitamin D signaling and many biological processes that regulate immune responses. The discovery of the vitamin D receptor in multiple immune cell lineages, such as monocytes, dendritic cells, and activated T cells credits vitamin D with a novel role in modulating immunological functions and its subsequent role in the development or prevention of autoimmune diseases. In this review we, discuss five major areas in vitamin D biology of high immunological significance: (1) the metabolism of vitamin D; (2) the significance of vitamin D receptor polymorphisms in autoimmune diseases, such as multiple sclerosis, type 1 diabetes mellitus, and systemic lupus erythematosus; (3) vitamin D receptor transcriptional regulation of immune cell lineages, including Th1, Th17, Th2, regulatory T, and natural killer T cells; (4) the prevalence of vitamin D insufficiency/deficiency in patients with multiple sclerosis, type 1 diabetes mellitus, and systemic lupus erythematosus; and finally, (5) the therapeutic effects of vitamin D supplementation on disease severity and progression.

Vitamin D in systemic and organ-specific autoimmune diseases

Lately, vitamin D has been linked with metabolic and immunological processes, which established its role as an essential component of human health preservation. Vitamin D has been defined as natural immune modulators, and upon activation of its receptors (VDRs), it regulates calcium metabolism, cellular growth, proliferation and apoptosis, and other immunological functions. Epidemiological data underline a strong correlation between poor vitamin D status and higher risk for chronic inflammatory illnesses of various etiologies, including autoimmune diseases. Epidemiological, genetic, and basic studies indicated a potential role of vitamin D in the pathogenesis of certain systemic and organ-specific autoimmune diseases. These studies demonstrate correlation between low vitamin D and prevalence of diseases. In addition, VDRs' polymorphisms observed in some of these autoimmune diseases may further support a plausible pathogenic link. Notably, for some autoimmune disease, no correlation with vitamin D levels could be confirmed. Thus, in the current review we present the body of evidence regarding the plausible roles of vitamin D and VDR's polymorphism in the pathogenesis of autoimmunity. We summarize the data regarding systemic (i.e., systemic lupus erythematosus, rheumatoid arthritis, etc.) and organ-specific (i.e., multiple sclerosis, diabetes mellitus, primary biliary cirrhosis, etc.) autoimmune diseases, in which low level of vitamin D was found comparing to healthy subjects. In addition, we discuss the correlations between vitamin D levels and clinical manifestations and/or activity of diseases. In this context, we address the rational for vitamin D supplementation in patients suffering from autoimmune diseases. Further studies addressing the mechanisms by which vitamin D affects autoimmunity and the proper supplementation required are needed.

Systemic Lupus Erythematosus: Old and New Susceptibility Genes versus Clinical Manifestations

Systemic Lupus Erythematosus (SLE) is one of the most relevant world-wide autoimmune disorders. The formation of autoantibodies and the deposition of antibody-containing immune complexes in blood vessels throughout the body is the main pathogenic mechanism of SLE leading to heterogeneous clinical manifestations and target tissue damage. The complexity of etiology and pathogenesis in SLE, enclosing genetic and environmental factors, apparently is one of the greatest challenges for both researchers and clinicians. Strong indications for a genetic background in SLE come from studies in families as well as in monozygotic and dizygotic twins, discovering several SLE-associated loci and genes (e.g. IRF5, PTPN22, CTLA4, STAT4 and BANK1). As SLE has a complex genetic background, none of these genes is likely to be entirely responsible for triggering autoimmune response in SLE even if they disclosure a potentially novel molecular mechanisms in the pathogenesis' disease. The clinical manifestations and disease severity varies greatly among patients, thus several studies try to associate clinical heterogeneity and prognosis with specific genetic polymorphisms in SLE associated genes. The continue effort to describe new predisposing or modulating genes in SLE is justified by the limited knowledge about the pathogenesis, assorted clinical manifestation and the possible prevention strategies. In this review we describe newly discovered, as well as the most studied genes associated to SLE susceptibility, and relate them to clinical manifestations of the disease.

Pharmacogenetics of the nuclear hormone receptors: the missing link between environment and drug effects?

In the last decade, genetic variations in ABC/SLC transporters and phase I/II enzymes have raised pharmacogenetic markers as being predictive to the attention of researchers in the field of personalized medicine in oncology. However, it is becoming evident that the sequence variations in these genes cannot address by themselves the sharp interindividual variability in drug effects. Recently, nuclear receptors (NRs), including pregnane X receptor, constitutive androstane receptor, retinoid X receptor, farnesoid X receptor, liver X receptor, vitamin D receptor, peroxisome proliferator-activated receptors and HNF4A, have demonstrated key roles in regulating transporter and metabolic gene expression in response to xeno/endobiotics, as well as antineoplastic drugs. These findings attracted interest to the genetics of the NRs for their possible role in influencing the metabolism and pharmacological profiles of chemotherapeutics. In this review, we aim to summarize the most recent findings in the innovative field of NR pharmacogenetics and findings in how they could integrate with more traditional markers in order to improve drug treatment personalization.