1,25-dihydroxyvitamin D3 selectively reduces interleukin-2 levels and proliferation of human T cell lines in vitro

Exploring the association between serum Vitamin D levels and the development of coronary artery lesions in Kawasaki disease - a systematic review

BACKGROUND

Kawasaki Disease (KD) involves arterial inflammation, primarily affecting the coronary arteries and leading to coronary artery lesions. Recent advancements in understanding the immunomodulatory roles of vitamin D have prompted investigations into the potential correlation between serum vitamin D levels and the risk of coronary artery lesions (CAL) in KD. This review aims to explore this association.

METHODS

A systematic search utilizing relevant keywords related to Kawasaki disease and coronary artery lesions was conducted across four databases (PubMed, Embase, Scopus, and Web of Science). The quality of the incorporated studies was assessed utilizing the Newcastle-Ottawa Scale. The study protocol is registered in PROSPERO under the registry code CRD42024493204.

RESULTS

In a review of five studies involving 442 KD patients and 594 healthy controls, KD patients generally had lower serum vitamin D levels compared to controls, with mixed findings on the association with coronary artery lesions and IVIG resistance. While three studies supported lower vitamin D in KD, one showed no significant difference. Regarding CAL, one study found lower vitamin D, another found higher levels associated with CAL, and two found no significant difference.

CONCLUSIONS

Overall, the evidence is inconclusive, but there's a trend suggesting potential benefits of sufficient vitamin D levels in Kawasaki disease rather than evidence refuting any association with clinical outcomes.

Vitamin D in Cutaneous T-Cell Lymphoma

Cutaneous T-cell lymphoma (CTCL) is characterized by the proliferation of malignant T cells in inflamed skin lesions. Mycosis fungoides (MF)-the most common variant of CTCL-often presents with skin lesions around the abdomen and buttocks ("bathing suit" distribution), i.e., in skin areas devoid of sun-induced vitamin D. For decades, sunlight and vitamin D have been connected to CTCL. Thus, vitamin D induces apoptosis and inhibits the expression of cytokines in malignant T cells. Furthermore, CTCL patients often display vitamin D deficiency, whereas phototherapy induces vitamin D and has beneficial effects in CTCL, suggesting that light and vitamin D have beneficial/protective effects in CTCL. Inversely, vitamin D promotes T helper 2 (Th2) cell specific cytokine production, regulatory T cells, tolerogenic dendritic cells, as well as the expression of immune checkpoint molecules, all of which may have disease-promoting effects by stimulating malignant T-cell proliferation and inhibiting anticancer immunity. Studies on vitamin D treatment in CTCL patients showed conflicting results. Some studies found positive effects, others negative effects, while the largest study showed no apparent clinical effect. Taken together, vitamin D may have both pro- and anticancer effects in CTCL. The balance between the opposing effects of vitamin D in CTCL is likely influenced by treatment and may change during the disease course. Therefore, it remains to be discovered whether and how the effect of vitamin D can be tilted toward an anticancer response in CTCL.

Transcriptomics identifies blunted immunomodulatory effects of vitamin D in people with multiple sclerosis

Vitamin D deficiency is a risk factor for developing multiple sclerosis (MS). However, the immune effects of vitamin D in people with MS are not well understood. We analyzed transcriptomic datasets generated by RNA sequencing of immune cell subsets (CD4+, CD8+ T cells, B cells, monocytes) from 33 healthy controls and 33 untreated MS cases. We utilized a traditional bioinformatic pipeline and weighted gene co-expression network analysis (WGCNA) to determine genes and pathways correlated with endogenous vitamin D. In controls, CD4+ and CD8+ T cells had 1079 and 1188 genes, respectively, whose expressions were correlated with plasma 25-hydroxyvitamin D level (P < 0.05). Functional enrichment analysis identified association with TNF-alpha and MAPK signaling. In CD4+ T cells of controls, vitamin D level was associated with expression levels of several genes proximal to multiple sclerosis risk loci (P = 0.01). Genes differentially associated with endogenous vitamin D by case-control status were enriched in TNF-alpha signaling via NF-κB. WGCNA suggested a blunted response to vitamin D in cases relative to controls. Collectively, our findings provide further evidence for the immune effects of vitamin D, and demonstrate a differential immune response to vitamin D in cases relative to controls, highlighting a possible mechanism contributing to MS pathophysiology.

Two lineages of immune cells that differentially express the vitamin D receptor

Since 1983 it has been known that monocytes and activated T and B cells expressed the vitamin D receptor (VDR) and are therefore vitamin D targets. New data identified two lineages of immune cells that can be differentiated by the expression of the VDR. Monocytes, macrophages, neutrophils, and hematopoietic stem cells were mostly from VDR positive lineages. T cells, ILC1 and ILC3 were also largely VDR positive, which is consistent with the known effects of vitamin D as regulators of type-1 and type-3 immunity. Activation of the VDR negative T cells did not induce the expression of the VDR reporter, suggesting that perhaps only a subset of the T cells in the periphery express the VDR. When activated, the VDR negative T cells responded as if they were VDR knockout T cells in that they made more IFN-γ and proliferated faster than the VDR positive T cells. The ability of vitamin D to regulate immune function will depend on which cells express the VDR and a better understanding of the signals that regulate VDR expression in immune cells.

A Novel Frailty Grade Combined with Cachexia Index and Osteopenia in Esophagectomy

BACKGROUNDS

The optimal method for evaluating frailty grade in patients with cancer has not been established in patients undergoing esophagectomy for esophageal cancer. This study aimed to clarify the impact of cachexia index (CXI) and osteopenia on survival in esophagectomized patients for esophageal cancer to develop frailty grade for risk stratification of the prognosis.

METHODS

A total of 239 patients who underwent esophagectomy were analyzed. CXI was calculated as follows: skeletal muscle index × serum albumin/neutrophil-to-lymphocyte ratio. Meanwhile, osteopenia was defined as below the cutoff value of bone mineral density (BMD) calculated by the receiver operating characteristic curve. We evaluated the average Hounsfield unit within a circle in the lower midvertebral core of the 11th thoracic vertebra on preoperative computed tomography as BMD.

RESULTS

Multivariate analysis revealed that low CXI (Hazard ratio [HR], 1.95; 95% confidence interval [CI], 1.25-3.04) and osteopenia (HR, 1.86; 95% CI, 1.19-2.93) were independent prognostic factors for overall survival. Meanwhile, low CXI (HR, 1.58; 95% CI, 1.06-2.34) and osteopenia (HR, 1.57; 95% CI, 1.05-2.36) were also significant prognostic factors for relapse-free survival. A frailty grade combined with CXI and osteopenia stratified into four groups by their prognosis.

CONCLUSIONS

Low CXI and osteopenia predict poor survival in patients undergoing esophagectomy for esophageal cancer. Furthermore, a novel frailty grade combined with CXI and osteopenia stratified the patients into four groups according to their prognosis.

Maternal vitamin D supplementation and treadmill exercise attenuated vitamin D deficiency-induced anxiety-and depressive-like behaviors in adult male offspring rats

BACKGROUND

Vitamin D is a vital neuroactive steroid for brain development and function. Vitamin D deficiency is a worldwide health problem, particularly in children and women. Gestational or developmental vitamin D deficiency is associated with an increased risk of neurodevelopmental and neuropsychiatric disorders. This study examined the effect of maternal vitamin D dietary manipulations and treadmill exercise on anxiety-and depressive-related behaviors, pro-inflammatory cytokines, and prefrontal cortex (PFC) protein levels of brain-derived neurotrophic factor (BDNF) and vitamin D receptor (VDR) in adult male offspring born to vitamin D-deficient diet (VDD)-fed dams.

METHODS AND RESULTS

Female rats were provided standard diet (SD) or VDD for six weeks and then were treated with SD (started a week before mating throughout gestation and lactation) and treadmill exercise (a week before mating until gestational day 20). Male offspring were separated on postnatal day (PND) 21 and fed SD chow until PND90. Our results demonstrated that maternal vitamin D deficiency increased anxiety and depression-related behaviors, increased levels of TNF-α and IL-1β in serum, and decreased prefrontal protein expressions of BDNF and VDR in adult male offspring. However, maternal vitamin D supplementation and treadmill exercise reversed these changes alone or in combination.

CONCLUSION

It seems that developmental vitamin D deficiency disrupts brain development and has a long-lasting effect on VDR and BDNF signaling in the rat brain resulting in neuropsychiatric disorders in offspring. Therefore, vitamin D supplementation and physical exercise are reasonable strategies to prevent these neurobehavioral impairments.

Vitamin D in Inflammatory Bowel Diseases. Mechanisms of Action and Therapeutic Implications

(1) Background: Vitamin D is an immunoregulatory factor influencing intestinal homeostasis. Recent evidence supports a central role of this micronutrient in the course of Inflammatory Bowel Diseases (IBD). This narrative review aims to provide a general overview of the possible biological mechanisms of action of vitamin D and its therapeutic implications in IBD. (2) Methods: A systematic electronic search of the English literature up to October 2021 was performed using Medline and the Cochrane Library. Only papers written in English that analyzed the role of vitamin D in IBD were included. (3) Results: In vitro and animal studies reported that vitamin D signaling improves epithelial barrier integrity regulating the expression of several junctional proteins, defensins, and mucins, modulates the inflammatory response, and affects gut microbiome composition. Recent studies also suggest that vitamin D deficiency is highly prevalent among IBD patients and that low serum levels correlate with disease activity and, less clearly, with disease course. (4) Conclusions: An increasing body of evidence suggests some role of vitamin D in the pathophysiology of IBD, nonetheless the underlying mechanisms have been so far only partially elucidated. A strong correlation with disease activity has been reported but its implication in the treatment is still undefined. Thus, studies focused on this issue, the definition of vitamin D levels responsible for clinical effects, and the potential role of vitamin D as a therapeutic agent are strongly encouraged.

Prognostic Significance of Preoperative Osteopenia in Patients Undergoing Esophagectomy for Esophageal Cancer

BACKGROUND

Osteopenia, which exhibits low bone mineral density (BMD), has been linked to sarcopenia and recently reported as a prognostic factor in various cancers. However, the prognostic significance of osteopenia in esophageal cancer remains unclear. Hence, this study aimed to clarify the impact of osteopenia on the prognosis of patients undergoing esophagectomy for esophageal cancer.

METHODS

We included 229 patients who underwent esophagectomy. BMD was calculated as the average pixel density (Hounsfield unit) within a circle in midvertebral core at the 11th thoracic vertebra on preoperative computed tomography. We then divided the patients into the Osteopenia group (n = 159) and the Non-Osteopenia group (n = 70) according to the optimal cutoff value obtained from the receiver operating characteristic curve. Their clinicopathological data, prognosis, and recurrence were analyzed.

RESULTS

The mean age was significantly older in the Osteopenia group (p = 0.047). The Osteopenia group had significantly worse overall survival (OS) and relapse-free survival (RFS) than the Non-Osteopenia group (p = 0.001 and p = 0.012, respectively). Multivariate analysis revealed osteopenia was an independent prognostic factor for OS (p < 0.001; hazard ratio [HR], 2.243; 95% confidence interval [CI], 1.422-3.538) and RFS (p = 0.008; HR, 1.739; 95% CI, 1.154-2.620). In logistic regression model, advanced age and cStage III-IV were independent risk factors for preoperative osteopenia.

CONCLUSIONS

Preoperative osteopenia is associated with poor survival and recurrence in patients undergoing esophagectomy for esophageal cancer.

Association between polymorphisms in the vitamin D receptor and susceptibility to multiple sclerosis

OBJECTIVES

Multiple sclerosis (MS) is a neurodegenerative chronic inflammatory. Mutations in the vitamin D receptor (VDR) gene can substantially affect serum vitamin D levels or alter its functionality, and can consequently increase susceptibility to developing MS. The objective of this study was to evaluate the association between polymorphisms in the VDR gene and risk of MS in a (Spanish) Caucasian population.

PATIENTS AND METHODS

We conducted a retrospective case-control study comprising 209 patients with relapsing-remitting multiple sclerosis (RRMS) and 836 controls of Caucasian origin from southern Spain. The ApaI (rs7975232), BsmI (rs1544410), Cdx2 (rs11568820), FokI (rs2228570), and TaqI (rs731236) gene polymorphisms were determined by allelic discrimination real-time PCR using TaqMan probes.

RESULTS

The recessive logical regression model, adjusted for age and sex, revealed that the TT genotype for VDR FokI (rs2228570) polymorphism was associated with higher risk of MS (P = 0.0150; OR = 1.82; 95% CI = 1.12-2.94; TT vs. CT + CC). No association between the other polymorphisms and development of MS was found in any of the models analyzed. The haplotype analysis, adjusted for age, smoking, and sex, did not find any statistically significant association between the haplotypes analyzed and risk of MS.

CONCLUSIONS

The VDR FokI (rs2228570) polymorphism was significantly associated with developing MS. We found no influence of the ApaI (rs7975232), BsmI (rs1544410), Cdx2 (rs11568820), FokI (rs2228570), and TaqI (rs731236) gene polymorphisms on the risk of developing MS in our patients.

Randomized Study Design to Test Effects of Vitamin D and Omega-3 Fatty Acid Supplementation as Adjuvant Therapy in Colorectal Cancer Patients

This study examines the effects of vitamin D and omega-3 fatty acid co-supplementation on inflammation and nutritional status in colorectal cancer patients. Patients were randomly assigned into four groups: (1) controls, receiving placebos; (2) omega-3 fatty acid arm, receiving two 330 mg omega-3 fatty acid capsules daily and placebo (for vitamin D₃) weekly; (3) vitamin D arm, receiving a 50,000 IU vitamin D₃ soft gel weekly and two placebos (for omega-3 fatty acids) daily; and (4) co-supplementation arm, receiving a 50,000 IU vitamin D₃ soft gel weekly and two 330 mg omega-3 fatty acids capsules daily for 8 weeks. As outcomes, we measure height; weight; fat-free mass (FFM); serum levels of 25(OH)D, TNF-α, and IL-6; C-CRP; and albumin, before and after the intervention. The presented results show that vitamin D₃ plus omega-3 fatty acid co-supplementation in colorectal cancer patients has beneficial impacts on inflammation and nutritional status.

Effects of dietary 25-hydroxyvitamin D3 supplementation on growth performance, immune function and antioxidative capacity in weaned piglets

The study evaluated the effects of different doses of 25-hydroxyvitamin D₃ (25(OH)D₃) on growth performance, immune function and antioxidative capacity in piglets. In a 21-d trial, 35 weaned pigs were divided into five groups and diets were supplemented with 5.5 (control), 43.0, 80.5, 118.0 and 155.5 μg 25(OH)D₃/kg, respectively. No treatment effects were observed for average daily gain, average daily feed intake and feed to gain ratio. Increasing dietary 25(OH)D₃ levels increased serum 25(OH)D₃ concentrations linearly (p < 0.01), decreased the frequency of CD3+CD4+ and CD3+CD8+ T cells (p < 0.01), and the serum level of complement component 3 (p < 0.05). Supplementation of 80.5 and 118.0 μg 25(OH)D₃/kg enhanced the activity of serum glutathione peroxidase (p < 0.05) and addition of 43.0 μg 25(OH)D₃/kg increased the malondialdehyde concentration (p < 0.05). Overall, feeding high-dose 25(OH)D₃ to weaned pigs partly improved immune functions and the antioxidative capacity.

Effects of Vitamin D and Omega-3 Fatty Acids Co-Supplementation on Inflammatory Factors and Tumor Marker CEA in Colorectal Cancer Patients Undergoing Chemotherapy: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Objectives: This study aimed to investigate the effects of vitamin D and omega-3 fatty acids co-supplementation on inflammatory factors and tumor marker CEA in colorectal cancer patients undergoing chemotherapy.Methods: In this study, 81 patients with stage ӀӀ or ӀӀӀ colorectal cancer were randomly assigned into four groups: (1) control: receiving a vitamin D placebo, weekly + two omega-3 fatty acid placebo capsules, daily; (2) omega-3 fatty acid, receiving two omega-3 fatty acid capsules (each capsule containing 330 mg of omega-3 fatty acids), daily + a vitamin D placebo, weekly; (3) vitamin D, receiving a 50,000 IU vitamin D soft gel, weekly + two omega-3 fatty acid placebo capsules, daily; (4) co-supplementation, receiving a 50,000 IU vitamin D soft gel, weekly + two omega-3 fatty acids capsules, for 8 weeks. Before and after the intervention, serum levels of 25(OH)D, TNF-α, IL-1β, IL-6, IL-8, NF-kB activity, and tumor marker CEA, were measured.Results: After 8 weeks of intervention, patients who received combined vitamin D and omega-3 fatty acids supplements compared with omega-3, vitamin D, and placebo had significantly decreased TNF-α, and IL-1β (P < .05). In addition, serum levels of TNF-α, IL-1β, IL-6, IL-8, and tumor marker CEA were decreased significantly in omega-3, vitamin D, and co-supplementation of them, compared with baseline. NF-kB activity was decreased significantly in vitamin D and co-supplementation groups, compared with baseline. Regarding CEA, there was no significant difference between the four groups at the end of intervention (P > .05).Conclusion: Results show that co-supplementation of vitamin D and omega-3 fatty acids co-supplementation, in colorectal cancer patients have beneficial impacts on inflammation and tumor marker CEA.

Macrophages Are Key Regulators of Stem Cells during Skeletal Muscle Regeneration and Diseases

Muscle regeneration is a closely regulated process that involves a variety of cell types such as satellite cells, myofibers, fibroadipogenic progenitors, endothelial cells, and inflammatory cells. Among these different cell types, macrophages emerged as a central actor coordinating the different cellular interactions and biological processes. Particularly, the transition of macrophages from their proinflammatory to their anti-inflammatory phenotype was shown to regulate inflammation, myogenesis, fibrosis, vascularization, and return to homeostasis. On the other hand, deregulation of macrophage accumulation or polarization in chronic degenerative muscle disorders was shown to impair muscle regeneration. Considering the key roles of macrophages in skeletal muscle, they represent an attractive target for new therapeutic approaches aiming at mitigating various muscle disorders. This review aims at summarizing the novel insights into macrophage heterogeneity, plasticity, and functions in skeletal muscle homeostasis, regeneration, and disease.

Escherichia coli Pathobionts Associated with Inflammatory Bowel Disease

Gut bacteria play a key role in initiating and maintaining the inflammatory process in the gut tissues of inflammatory bowel disease (IBD) patients, by supplying antigens or other stimulatory factors that trigger immune cell activation. Changes in the composition of the intestinal microbiota in IBD patients compared to that in healthy controls and a reduced diversity of intestinal microbial species are linked to the pathogenesis of IBD. Adherent invasive Escherichia coli (AIEC) has been linked to Crohn's disease (CD) patients, while diffusely adherent E. coli (DAEC) has been associated with ulcerative colitis (UC). Bacteriological analysis of intestinal biopsy specimens and fecal samples from IBD patients shows an increased number of E. coli strains belonging to the B2 phylogenetic group, which are typically known as extraintestinal pathogenic E. coli (ExPEC). Results from studies of both cell cultures and animal models reveal pathogenic features of these E. coli pathobionts, which may link them to IBD pathogenesis. This suggests that IBD-associated E. coli strains play a facilitative role during IBD flares. In this review, we explain IBD-associated E. coli and its role in IBD pathogenesis.

Vitamin D status during pregnancy and offspring outcomes: a systematic review and meta-analysis of observational studies

BACKGROUND/OBJECTIVES

Vitamin D deficiency during pregnancy may influence adverse outcomes in offspring. The aim of this systematic review and meta-analysis of observational studies was to assess the association between low prenatal concentrations of 25(OH)D (by using three different cut-off levels), preterm birth (PTB) and anthropometric and neurodevelopmental outcomes in offspring.

SUBJECTS/METHODS

Studies reporting data on the association between maternal vitamin D concentrations and offspring outcomes identified through a systematic review of scientific literature published in PubMed/MEDLINE, Scopus and the Cochrane Library databases up to April 2017.

RESULTS

We included 54 eligible studies. Vitamin D-deficient mothers (<30 nmol/L) had offspring with lower birthweight (MD -87.82 g; 95% CI -119.73, -55.91 g), head circumference (MD -0.19 cm; 95% CI -0.32, -0.06 cm) and a higher risk of small for gestational age (SGA) infants and PTB (OR 1.59; 95% CI 1.24, 2.03) compared to mothers with concentrations ≥30 nmol/L. Vitamin D insufficiency (<50 nmol/L) was associated with a higher risk of SGA and PTB (OR 1.43; 95% CI 1.08, 1.91 and OR 1.28; 95% CI 1.08, 1.52, respectively). Concentrations of 25(OH)D ≥75 nmol/L were not found to be associated with birthweight, SGA or PTB. Offspring of vitamin D-insufficient mothers had lower scores in mental (MD -1.12 points; 95% CI -1.82, -0.42 cm) and language developmental tests (MD -0.35 points; 95% CI -1.00, 0.31 cm).

CONCLUSION

Maternal vitamin D deficiency is associated with offspring adverse anthropometric outcomes and PTB; insufficiency with a higher risk of SGA, PTB and adverse neurodevelopmental outcomes.

Effect of vitamin D supplementation on inflammation and nuclear factor kappa-B activity in overweight/obese adults: a randomized placebo-controlled trial

In-vitro studies suggest that vitamin D reduces inflammation by inhibiting nuclear factor kappa-B (NFκB) activity. Yet, no trials have examined the effects of vitamin D supplementation on NFκB activity in-vivo in humans. We conducted a double-blind randomized trial (RCT) examining effects of vitamin D supplementation on inflammatory markers and NFκB activity in peripheral blood mononuclear cells (PBMCs). Sixty-five overweight/obese, vitamin D-deficient (25-hydroxyvitamin D [25(OH)D] ≤ 50 nmol/L) adults were randomized to a single 100,000 IU bolus followed by 4,000 IU daily cholecalciferol or matching placebo for 16 weeks. We measured BMI, % body fat, serum 25(OH)D, high-sensitivity C-reactive protein (hsCRP), tumour necrosis factor (TNF), monocyte chemoattractant protein-1 (MCP-1), interferon-gamma (IFN-γ), several interleukins, and NFκB activity in PBMCs. Fifty-four participants completed the study. Serum 25(OH)D concentrations increased with vitamin D supplementation compared to placebo (p < 0.001). Vitamin D and placebo groups did not differ in any inflammatory markers or NFκB activity (all p > 0.05). Results remained non-significant after adjustment for age, sex, and % body fat, and after further adjustment for sun exposure, physical activity, and dietary vitamin D intake. Although in-vitro studies report anti-inflammatory effects of vitamin D, our RCT data show no effect of vitamin D supplementation on inflammatory markers or NFκB activity in-vivo in humans.

Modulatory effects of vitamin D on peripheral cellular immunity in patients with recurrent miscarriage

PROBLEM

We aimed to investigate the modulatory effects of vitamin D on peripheral blood cellular immune response in patients with recurrent miscarriage (RM).

METHOD OF STUDY

The effect of vitamin D on the number of peripheral blood cells, T helper 1 (Th1) cytokines, and NK cytotoxicity was measured in 99 women with RM.

RESULTS

The percentage of CD19⁺ B cells and NK cytotoxicity at an effector-to-target cell (E:T) ratio of 50:1, 25:1, and 12.5:1 were significantly higher in the vitamin D insufficiency group (VDI) than in the vitamin D normal group (VDN) (P<.05 each). The proportion of TNF-α-expressing Th cells was significantly higher in the vitamin D deficiency group (VDD) than in VDN (P<.05). However, there were no significant differences between VDI and VDD. This dysregulation was significantly reduced with 1,25(OH)₂ D supplementation.

CONCLUSION

The data suggest that the abnormalities of cellular immune response were observed in RM patients with a low vitamin D level, which could be regulated to some extent with 1,25(OH)₂ D supplementation.

Recent advances in complementary and replacement therapy with nutraceuticals in combating gastrointestinal illnesses

The digestive system provides nourishment to the whole body. Disorders in this system would result in many associated illnesses as the body is deprived of essential nutrients. Gastrointestinal diseases, in particular, gastric ulceration, inflammatory bowel diseases and colorectal cancer have become more prevalent in all population age groups. While this can be attributed to diet and lifestyle changes, the measures to combat these illnesses with conventional drugs is losing popularity owing to the harsh side effects, drug resistance and lack of patient compliance. The focus of this review is to endorse promising nutraceutical dietary components such as phytosterols, polyphenols, anthocyanins and polyunsaturated fatty acids and their synergistic value, in combination with conventional management of key gastrointestinal diseases. As most of these nutraceuticals are labile compounds, the need for protection and delivery using a carrier system is stressed and the methods for targeting to specific parts of the gastrointestinal tract are discussed. A section has also been devoted to perspectives on co-encapsulation methods of drugs and nutraceuticals using different particle systems. Multilayered carrier systems like double layered and core shell particles have been proposed as an exemplary system to co-encapsulate both drugs and nutrients while keeping them segregated.

Vitamin D: Immuno-modulation and tuberculosis treatment

Tuberculosis (TB) is a major global health problem and often coincides with vitamin D deficiency. High doses of vitamin D were widely used to treat TB during the pre-antibiotic era. Vitamin D exerts its action through vitamin D receptor (VDR), and VDR gene polymorphisms are associated with susceptibility or resistance to tuberculosis as well as sputum smear and culture conversion during anti-TB treatment. In-vitro studies have revealed that 1,25-dihydroxyvitamin D3 enhances innate immunity by increased expression of various antimicrobial peptides, including cathelicidin, and induction of autophagy of the infected cells thus restricts the intracellular growth of Mycobacterium tuberculosis in macrophages. On the other hand, vitamin D has been shown to suppress the pro-inflammatory cytokine response and enhance the anti-inflammatory response. Supplementation with vitamin D in concert with treatment for TB may be beneficial with respect to minimizing the excessive tissue damage that occurs during the active stage of tuberculosis disease. Several clinical trials have evaluated vitamin D supplementation as an adjunct therapy in the treatment for tuberculosis. However, results are conflicting, owing to variations in dose regimens and outcomes. Further investigations are needed to find the optimal concentration of vitamin D for supplementation with standard anti-TB drugs to optimize treatment, which could help to effectively manage both drug-sensitive and drug-resistant tuberculosis.

Environmental factors and multiple sclerosis severity: a descriptive study

Growing evidence suggests that environmental factors play a key role in the onset of multiple sclerosis (MS). This study was conducted to examine whether environmental factors may also be associated with the evolution of the disease. We collected data on smoking habits, sunlight exposure and diet (particularly consumption of vitamin D-rich foods) from a sample of 131 MS patients. We also measured their serum vitamin D concentration. The clinical impact of MS was quantified using the Multiple Sclerosis Severity Score (MSSS); MS was considered “severe” in patients with MSSS ≥ 6, and “mild” in patients with MSSS ≤ 1. The results showed a strong association between serum vitamin D concentration and both sunlight exposure (26.4 ± 11.9 ng/mL vs. 16.5 ± 12.1 ng/mL, p = 0.0004) and a fish-rich diet (23.5 ± 12.1 ng/mL vs. 16.1 ± 12.4 ng/mL, p = 0.005). Patients reporting frequent sunlight exposure had a lower MSSS (2.6 ± 2.4 h vs. 4.6 ± 2.6 h, p < 0.001). The mild MS patients reported much more frequent sunlight exposure (75% mild MS vs. 25% severe MS p = 0.004, Chi square test). A higher serum vitamin D concentration determined a lower risk of developing severe MS, adjusted for sunlight exposure (OR = 0.92 for one unit increase in vitamin D, 95% CI: 0.86–0.97, p = 0.005). A stronger inverse association emerged between frequent sunlight exposure and the risk of severe MS (OR = 0.26, 95% CI: 0.09–0.71, p = 0.009). Our data show that an appropriate diet and adequate expose to sunlight are associated with less aggressive MS.

Vitamin D, immune regulation, the microbiota, and inflammatory bowel disease

The inflammatory bowel diseases are complex diseases caused by environmental, immunological, and genetic factors. Vitamin D status is low in patients with inflammatory bowel diseases, and experimental inflammatory bowel diseases are more severe in vitamin D-deficient or vitamin D receptor knockout animals. Vitamin D is beneficial in inflammatory bowel diseases because it regulates multiple checkpoints and processes essential for homeostasis in the gut. Vitamin D inhibits IFN-γ and IL-17 production while inducing regulatory T cells. In addition, vitamin D regulates epithelial cell integrity, innate immune responses, and the composition of the gut microbiota. Overall, vitamin D regulates multiple pathways that maintain gastrointestinal homeostasis. The data support improving vitamin D status in patients with inflammatory bowel diseases.

Feeding the immune system

A well-functioning immune system is key to providing good defence against pathogenic organisms and to providing tolerance to non-threatening organisms, to food components and to self. The immune system works by providing an exclusion barrier, by identifying and eliminating pathogens and by identifying and tolerating non-threatening sources of antigens, and by maintaining a memory of immunological encounters. The immune system is complex involving many different cell types distributed throughout the body and many different chemical mediators some of which are involved directly in defence while others have a regulatory role. Babies are born with an immature immune system that fully develops in the first few years of life. Immune competence can decline with ageing. The sub-optimal immune competence that occurs early and late in life increases susceptibility to infection. Undernutrition decreases immune defences, making an individual more susceptible to infection. However, the immune response to an infection can itself impair nutritional status and alter body composition. Practically all forms of immunity are affected by protein-energy malnutrition, but non-specific defences and cell-mediated immunity are most severely affected. Micronutrient deficiencies impair immune function. Here, vitamins A, D and E, and Zn, Fe and Se are discussed. The gut-associated lymphoid tissue is especially important in health and well-being because of its close proximity to a large and diverse population of organisms in the gastrointestinal tract and its exposure to food constituents. Certain probiotic bacteria which modify the gut microbiota enhance immune function in laboratory animals and may do so in human subjects.

Contribution of vitamin D insufficiency to the pathogenesis of multiple sclerosis

The contribution of vitamin D insufficiency to the pathogenesis of multiple sclerosis (MS) is reviewed. Among the multiple recently discovered actions of vitamin D, an immunomodulatory role has been documented in experimental autoimmune encephalomyelitis and in humans. This action in the peripheral immune system is currently the main known mechanism through which vitamin D might influence MS, but other types of actions could be involved within the central nervous system. Furthermore, vitamin D insufficiency is widespread in temperate countries and in patients with MS at the earliest stages of the disease, suggesting that the deleterious effects related to vitamin D insufficiency may be exerted in these patients. In fact, many genetic and environmental risk factors appear to interact and contribute to MS. In genetics, several human leukocyte antigen (HLA) alleles (more particularly HLA-DRB1*1501) could favour the disease whereas some others could be protective. Some of the genes involved in vitamin D metabolism (e.g. CYP27B1) also play a significant role. Furthermore, three environmental risk factors have been identified: past Epstein-Barr virus infection, vitamin D insufficiency and cigarette smoking. Interactions between genetic and environmental risk or protective factors may occur during the mother's pregnancy and could continue during childhood and adolescence and until the disease is triggered in adulthood, therefore possibly modulating the MS risk throughout the first decades of life. Furthermore, some clinical findings already strongly suggest that vitamin D status influences the relapse rate and radiological lesions in patients with MS, although the results of adequately powered randomized clinical trials using vitamin D supplementation have not yet been reported. While awaiting these incontrovertible results, which might be long in coming, patients with MS who are currently in vitamin D insufficiency should be supplemented, at least for their general health status, using moderate doses of the vitamin.

Maternal vitamin D status and adverse pregnancy outcomes: a systematic review and meta-analysis

OBJECTIVE

To estimate the associations between maternal vitamin D status and adverse pregnancy outcomes.

STUDY DESIGN

We searched electronic databases of the human literature in PubMed, EMBASE and the Cochrane Library up to October, 2012 using the following keywords: "vitamin D" and "status" or "deficiency" or "insufficiency" and "pregnancy". A systematic review and meta-analysis were conducted on observational studies that reported the association between maternal blood vitamin D levels and adverse pregnancy outcomes including preeclampsia, gestational diabetes mellitus (GDM), preterm birth or small-for-gestational age (SGA).

RESULTS

Twenty-four studies met the inclusion criteria. Women with circulating 25-hydroxyvitamin D [25(OH)D] level less than 50 nmol/l in pregnancy experienced an increased risk of preeclampsia [odds ratio (OR) 2.09 (95% confidence intervals 1.50-2.90)], GDM [OR 1.38 (1.12-1.70)], preterm birth [OR 1.58 (1.08-2.31)] and SGA [OR 1.52 (1.08-2.15)].

CONCLUSION

Low maternal vitamin D levels in pregnancy may be associated with an increased risk of preeclampsia, GDM, preterm birth and SGA.

Effect of vitamin D3 on chemokine expression in pulmonary tuberculosis

1,25 Dihydroxy vitamin D(3) (vitamin D(3)) is an immunomodulator and its deficiency has been associated with susceptibility to tuberculosis. We have studied the immunoregulatory role of vitamin D(3) on various chemokine expression in pulmonary tuberculosis. Peripheral blood mononuclear cells obtained from 21 pulmonary tuberculosis (PTB) patients and 24 healthy controls (HCs) were cultured for 48 h with culture filtrate antigen (CFA) of Mycobacterium tuberculosis with or without vitamin D(3) at a concentration 1 × 10(-7)M. The relative mRNA expression of monocyte chemoattractant protein-1 (MCP-1, CCL2), macrophage inflammatory protein-1α (MIP-1α, CCL3), macrophage inflammatory protein-1β (MIP-1β, CCL4), and regulated upon-activation, normal T cell-expressed and secreted (RANTES, CCL5) and IFN-γ inducible protein-10 (IP-10, CXCL10) chemokines were estimated from 48 h old macrophages using real-time polymerase chain reaction (RT-PCR). The culture supernatants were used to estimate the various chemokines including monokine induced by IFN-γ (MIG, CXCL9) levels using cytometric bead array. In HCs, vitamin D(3) significantly suppressed the MCP-1 mRNA expression of CFA stimulated cells (p=0.0027), while no such effect was observed in PTB patients. Vitamin D(3) showed no significant effect on MIP-1α, MIP-1β and RANTES in both the study groups. The CFA induced IP-10 mRNA and protein expression was significantly suppressed by vitamin D(3) in both the study groups (p<0.05). A similar suppressive effect of vitamin D(3) was observed with MIG protein in healthy controls (p=0.0029) and a trend towards a suppression was observed in PTB patients. The suppressive effect of vitamin D(3) is more prominent in CXC chemokines rather than CC chemokines. This suggests that vitamin D(3) may down regulate the recruitment and activation of T-cells through CXC chemokines at the site of infection and may act as a potential anti-inflammatory agent.

Factors associated with the performance of a blood-based interferon-γ release assay in diagnosing tuberculosis

Background

Indeterminate results are a recognised limitation of interferon-γ release assays (IGRA) in the diagnosis of latent tuberculosis (TB) infection (LTBI) and TB disease, especially in children. We investigated whether age and common co-morbidities were associated with IGRA performance in an unselected cohort of resettled refugees.

Methods

A retrospective cross-sectional study of refugees presenting for their post-resettlement health assessment during 2006 and 2007. Refugees were investigated for prevalent infectious diseases, including TB, and for common nutritional deficiencies and haematological abnormalities as part of standard clinical screening protocols. Tuberculosis screening was performed by IGRA; QuantiFERON-TB Gold in 2006 and QuantiFERON-TBGold In-Tube in 2007.

Results

Complete data were available on 1130 refugees, of whom 573 (51%) were children less than 17 years and 1041 (92%) were from sub-Saharan Africa. All individuals were HIV negative. A definitive IGRA result was obtained in 1004 (89%) refugees, 264 (26%) of which were positive; 256 (97%) had LTBI and 8 (3%) had TB disease. An indeterminate IGRA result was obtained in 126 (11%) refugees (all failed positive mitogen control). In multivariate analysis, younger age (linear OR  = 0.93 [95% CI 0.91–0.95], P<0.001), iron deficiency anaemia (2.69 [1.51–4.80], P = 0.001), malaria infection (3.04 [1.51–6.09], P = 0.002), and helminth infection (2.26 [1.48–3.46], P<0.001), but not vitamin D deficiency or insufficiency, were associated with an indeterminate IGRA result.

Conclusions

Younger age and a number of common co-morbidities are significantly and independently associated with indeterminate IGRA results in resettled predominantly African refugees.

1,25-Dihydroxyvitamin D3 inhibits proliferation but not the suppressive function of regulatory T cells in the absence of antigen-presenting cells

Vitamin D3 is known to induce regulatory T (Treg) cells by rendering antigen-presenting cells tolerogenic, its direct effect on human naturally occurring Treg cells is unclear. Here, we investigated if and how 1,25-dihydroxyvitamin D(3) [1,25(OH)2D3] can directly affect the proliferation and function of human naturally occurring Treg cells in vitro. First, we demonstrated that these Treg cells express vitamin D receptors that were up-regulated following anti-CD3/CD28-bead stimulation. 1,25(OH)2D3 inhibited proliferation of Treg cells even when exogenous interleukin-2 was provided. Treg cells were more susceptible to the inhibitory effect of 1,25(OH)2D3 than conventional T cells(.) 1,25(OH)2D3 neither affected the anergic state nor the suppressive function of Treg cells but induced a subtle increase in interleukin-10-secreting cells. The cell-division-inhibiting effect of 1,25(OH)2D3 on Treg cells was also demonstrated in vivo by supplementing vitamin D-deficient HIV-1-infected patients with 2000 IU cholecalciferol (vitamin D3). Increased serum 1,25(OH)2D3 levels were associated with a drop in the number and percentage of Treg cells, which may be attributed to a decrease in the proliferating Foxp3+ Treg cell population. In conclusion, 1,25(OH)2D3 directly affects Treg cell growth and promotes interleukin-10 production without apparent effects on activation status and suppressive phenotype whereas in vivo, high serum 1,25(OH)2D3 levels are associated with reduced Treg cell proliferation and a reduced number of Treg cells.

IFN-α primes T- and NK-cells for IL-15-mediated signaling and cytotoxicity

Recently it has become clear that interferon (IFN)-α, a type I interferon produced rapidly in response to infection, not only plays a key role in innate immunity, but also promotes adaptive immune responses by influencing the production or function of other cytokines. During infections IFN-α fosters the production of IL-15, which plays a pivotal role in the development, survival and function of NK cells and recruitment and activation of T cells. Since these two cytokines exert overlapping functions during infections, this investigation was undertaken to study the priming effect of IFN-α on the effect of IL-15 on human T and NK cells. We show that IFN-α induces an increased expression of IL-15Rα in human activated peripheral T cells, and in CD8(+) and CD4(+) T-cell lines. Functionally, the IFN-α-enhanced IL-15Rα expression resulted in an enhanced IL-15-mediated phosphorylation of STAT5 and STAT3 followed by a further increase in IL-15Rα expression. Moreover, IFN-α significantly increased the IL-15-induced cytotoxic activity of freshly isolated T and NK cells. Taken together, our data show that IFN-α boosts signaling and functional effects of IL-15, at least in part by fostering the increased IL-15R expression, thus add new facet to the emerging role of IFN-α as an important primer of adaptive immune responses.

Why do T cells express the vitamin D receptor?

Vitamin D is an important regulator of immune function. T cells express the vitamin D receptor (VDR) and have been shown to be direct and indirect vitamin D targets. Why should T cells be responsive to vitamin D? The data suggest that expression of the VDR is required for the development of two cell types, NKT cells and CD8αα T cells, which inhibit autoimmunity. In addition, effector T cell cytokine production is regulated by vitamin D. Available evidence suggests that NKT and CD8αα T cells express the VDR as part of the selection process to protect against the generation of autoimmunity, particularly in the gut.

Vitamin D may be a link to black-white disparities in adverse birth outcomes

In the United States, significant, intractable disparities exist in rates of major pregnancy outcomes between non-Hispanic black and non-Hispanic white women. A previously unexplored candidate influence on the black-white disparity in adverse birth outcomes is maternal vitamin D status. This review summarizes the evidence relating maternal vitamin D to preeclampsia, spontaneous preterm birth, gestational diabetes, and fetal growth restriction, and addresses gaps in our understanding of the contribution of vitamin D to the intractable black-white disparity in these conditions. The literature reviewed highlights strong biologic plausibility of role for vitamin D in the pathophysiology of these poor pregnancy outcomes. Data also suggest that maternal vitamin D deficiency may increase the risk of preeclampsia and fetal growth restriction. Less research has been done in support of relations with spontaneous preterm birth and gestational diabetes, and fetal and infant survival have rarely been studied. Few trials of vitamin D supplementation have been conducted in pregnant women with adequate power to test effects on birth outcomes. Importantly, black pregnant women have rarely been studied in vitamin D-birth outcomes research. Although vitamin D is a promising candidate influence on black-white disparities in preeclampsia, spontaneous preterm birth, fetal growth restriction, and gestational diabetes, these associations require further study in large samples of black US women. Because vitamin D deficiency is widespread and black-white disparities in pregnancy outcomes and infant survival have been resistant to previous interventions, research to test vitamin D as a causal factor is of major public health significance.

TARGET AUDIENCE

Obstetricians & Gynecologist, Family Physicians.

LEARNING OBJECTIVES

After completion of this educational activity, the reader will be able to appreciate risk factors for inadequate vitamin D status. Understand the basic aspects of vitamin D metabolism. Become aware of recent literature linking inadequate vitamin D status and adverse pregnancy outcomes such as preeclampsia and preterm birth.

Vitamin-regulated cytokines and growth factors in the CNS and elsewhere

There is a growing awareness that natural vitamins (with the only exception of pantothenic acid) positively or negatively modulate the synthesis of some cytokines and growth factors in the CNS, and various mammalian cells and organs. As natural vitamins are micronutrients in the human diet, studying their effects can be considered a part of nutritional genomics or nutrigenomics. A given vitamin selectively modifies the synthesis of only a few cytokines and/or growth factors, although the same cytokine and/or growth factor may be regulated by more than one vitamin. These effects seem to be independent of the effects of vitamins as coenzymes and/or reducing agents, and seem to occur mainly at genomic and/or epigenetic level, and/or by modulating NF-kappaB activity. Although most of the studies reviewed here have been based on cultured cell lines, but their findings have been confirmed by some key in vivo studies. The CNS seems to be particularly involved and is severely affected by most avitaminoses, especially in the case of vitamin B(12). However, the vitamin-induced changes in cytokine and growth factor synthesis may initiate a cascade of events that can affect the function, differentiation, and morphology of the cells and/or structures not only in the CNS, but also elsewhere because most natural vitamins, cytokines, and growth factors cross the blood-brain barrier. As cytokines are essential to CNS-immune and CNS-hormone system communications, natural vitamins also interact with these circuits. Further studies of such vitamin-mediated effects could lead to vitamins being used for the treatment of diseases which, although not true avitaminoses, involve an imbalance in cytokine and/or growth factor synthesis.

Circulating 25-hydroxyvitamin d levels and survival in patients with colorectal cancer

PURPOSE

Higher plasma 25-hydroxyvitamin D(3) (25(OH)D) levels are associated with a decreased incidence of colorectal cancer, but the influence of plasma 25(OH)D on the outcome of patients with established colorectal cancer is unknown.

PATIENTS AND METHODS

We prospectively examined the association between prediagnosis 25(OH)D levels and mortality among 304 participants in the Nurses' Health Study (NHS) and the Health Professionals Follow-Up Study (HPFS) who were diagnosed with colorectal cancer from 1991 to 2002. Participants diagnosed within 2 years of blood collection were excluded. Patients were observed until death, June 2005 (NHS), or January 2005 (HPFS), whichever came first. The primary end point was overall mortality. Cox proportional hazards models were used to calculate hazard ratios (HR) adjusted for other risk factors for cancer survival.

RESULTS

Higher plasma 25(OH)D levels were associated with a significant reduction in overall mortality (P for trend = .02). Compared with the lowest quartile, participants in the highest quartile had an adjusted HR of 0.52 (95% CI, 0.29 to 0.94) for overall mortality. A trend toward improved colorectal cancer-specific mortality was also seen (HR = 0.61; 95% CI, 0.31 to 1.19). The results remained unchanged after excluding patients diagnosed within 5 years of blood collection (P for trend = .04); the multivariate HR for overall mortality comparing extreme quartiles was 0.45 (95% CI, 0.19 to 1.09).

CONCLUSION

Among patients with colorectal cancer, higher prediagnosis plasma 25(OH)D levels were associated with a significant improvement in overall survival. Further study of the vitamin D pathway and its influence on colorectal carcinogenesis and cancer progression is warranted.

Regulatory role of promoter and 3' UTR variants of vitamin D receptor gene on cytokine response in pulmonary tuberculosis

Vitamin D receptor (VDR) gene variants are shown to regulate immune response in tuberculosis. We studied the influence of VDR promoter (Cdx-2 and A1012G), 3' untranslated region (Apa I, Bsm I, and Taq I) and start codon (Fok I) polymorphisms on 1,25(OH)(2)D(3)-modulated IL-12p40, IFN-gamma, IL-10, and IL-5 response to live Mycobacterium tuberculosis and its culture filtrate antigen (CFA) in 60 normal healthy subjects and 51 pulmonary tuberculosis patients. In peripheral blood mononuclear cell cultures with CFA and 1,25(OH)(2)D(3), IL-12p40, and IFN-gamma levels were significantly decreased (p < 0.05) and IL-10 levels were significantly increased (p < 0.05) in patients with GG genotype. The extended genotype bbaaTT (baT haplotype) was associated with decreased IL-12p40 and IFN-gamma levels and significantly increased IL-10 levels (p < 0.05). The Cdx-2 GG genotype and baT haplotype are associated with a suppressed Th1 and increased IL-10 response, which suggests that 1,25(OH)(2)D(3) probably through the VDR polymorphic variants augments the anti-inflammatory response at the site of M. tuberculosis infection.

1, 25 Dihydroxyvitamin D3 modulated cytokine response in pulmonary tuberculosis

1, 25 Dihydroxyvitamin D(3) (1, 25(OH)(2) D(3)) has gained significant importance in tuberculosis with regard to its immunoregulatory activities. Our aim was to evaluate the effect of 1, 25(OH)(2) D(3) on cytokine response to Mycobacterium tuberculosis antigens in pulmonary tuberculosis. Peripheral blood mononuclear cells obtained from 60 healthy controls and 52 pulmonary tuberculosis patients were cultured with culture filtrate antigen (CFA) of M. tuberculosis and live M. tuberculosis with and without 1, 25(OH)(2) D(3) (10(-9), 10(-8)and 10(-7)M concentrations). The culture supernatants were used to estimate IL-8, IL-6, TGF-beta, IL-10, IFN-gamma, IL-12p40, IL-2, IL-4 and IL-5 levels by ELISA. 1, 25 Dihydroxyvitamin D(3) significantly suppressed IL-12p40 and IFN-gamma production in response to CFA and live M. tuberculosis with a maximum suppression at 10(-7)M concentration (p<0.0001). In CFA stimulated cultures, addition of 1, 25(OH)(2) D(3) significantly suppressed IL-8, IL-6 and IL-10 whereas the IL-2 levels were significantly increased in controls. It variably influenced the Th2 cytokines, showing an increased trend for IL-4 and suppressed IL-5 levels. We report that 1, 25(OH)(2) D(3) differentially modulates production of cytokines in response to M. tuberculosis antigens by predominantly suppressing IL-12p40 and IFN-gamma production in a dose dependent manner. Our results suggest a role for vitamin D in restricting acquired immune response against tuberculosis by regulating cytokine production.

Vitamin D Status and the Metabolic Syndrome

The identification of vitamin D receptor expression in different tissues suggests a widespread role for vitamin D action beyond its classical function in bone and mineral metabolism. Recently, the importance of vitamin D status as a risk factor in the development of metabolic syndrome has been the focus of several studies.

22-ene-25-oxa-vitamin D: a new vitamin D analogue with profound immunosuppressive capacities

BACKGROUND

The biologic role of 1,25-dihydroxyvitamin D(3), such as anti-inflammatory functions, reduction of cytokine production by T cells and immunoglobulin production by B cells, is well established. However, its clinical use as an immunosuppressive agent is limited because of the hypercalcemic toxicity occurring after systemic application. The purpose of this study was to investigate the immunmodulatory effects of 22-ene-25-oxa-vitamin D (ZK156979), a novel low calcemic vitamin D analogue.

MATERIALS AND METHODS

Human peripheral blood mononuclear cells (PBMCs) from healthy donors were isolated using the Ficoll Hypaque technique, cultured for 24 h and treated with different concentrations of ZK156979 ranging from 10(-5) to 10(-10) mol L(-1) compared with 1,25-dihydroxyvitamin D(3)[10(-5)-10(-10) mol L(-1)] following phytohaemagglutinin (PHA) stimulation. Interferon gamma (IFNgamma), tumour necrosis factor alpha (TNFalpha), interleukin 1 beta (IL-1beta), interleukin 10 (IL-10) and interleukin 4 (IL-4) secretion in supernatants were measured by ELISA.

RESULTS

ZK156979 inhibited the PHA-induced Th1-response (IFNgamma and TNFalpha levels) and the macrophage-product IL-1beta in a concentration-dependent manner (10(-10)-10(-5) mol L(-1)) with the efficiency on cytokine expression compared with 1,25-dihydroxyvitamin D(3) being slightly reduced. In contrast, ZK156979 and 1,25-dihydroxyvitamin D(3) both affected the Th2 response, leading to significantly increased IL-10- and IL-4 secretion.

CONCLUSIONS

ZK156979 is a member of novel vitamin D analogues revealing prominent immunomodulatory and suppressive characteristics with distinctive inhibition of Th1-cytokines whereas the Th2 compartment is augmented, thus providing a considerable therapeutic potential in T-cell -mediated diseases.

Effect of vitamin D3 on phagocytic potential of macrophages with live Mycobacterium tuberculosis and lymphoproliferative response in pulmonary tuberculosis

Immune responses are elicited through antigen presentation and recognition by macrophages and T-lymphocytes, respectively. The immunomodulatory effect of vitamin D(3) on macrophage phagocytic potential with live Mycobacterium tuberculosis, spontaneous and M. tuberculosis culture filtrate antigen induced lymphocyte responses were studied in pulmonary tuberculosis patients (PTBPs) ( n = 31) and normal healthy subjects (NHSs) ( n = 43). Vitamin D(3) at a concentration of 10(-7) M significantly enhanced the macrophage phagocytosis of live M. tuberculosis in normal subjects with low phagocytic potential (less than 10%) ( p = 0.015). No such increase was observed in PTBPs. Vitamin D(3) significantly decreased the spontaneous lymphoproliferative response ( p = 0.022) and increased the apoptosis of peripheral blood mononuclear cells in PTBPs ( p = 0.024). In normals, vitamin D(3) increased the spontaneous lymphoproliferative response. An inverse correlation between macrophage phagocytosis and spontaneous response was observed in NHSs, whereas a direct correlation was seen between vitamin D(3)-treated cells in normal subjects under in vitro condition. Vitamin D(3) decreased the M. tuberculosis culture filtrate antigen induced lymphocyte response significantly in normal subjects ( p = 0.0003), while it had no influence on the lymphocyte response in PTBPs. The present study suggests that exposure to vitamin D(3) increases the phagocytic potential and spontaneous lymphoproliferative response but brings down the antigen-induced response in normals. In tuberculosis, addition of vitamin D(3) has no significant effect on antigen-induced lymphoproliferative response. This may be due to the unresponsive nature of the cells to the action of vitamin D(3) by virtue of the disease, which renders them inactive.