Vitamin D and respiratory health

Activation of vitamin D regulates response of human bronchial epithelial cells to Aspergillus fumigatus in an autocrine fashion

Aspergillus fumigatus (A. fumigatus) is one of the most common fungi to cause diseases in humans. Recent evidence has demonstrated that airway epithelial cells play an important role in combating A. fumigatus through inflammatory responses. Human airway epithelial cells have been proven to synthesize the active vitamin D, which plays a key role in regulating inflammation. The present study was conducted to investigate the impact of A. fumigatus infection on the activation of vitamin D and the role of vitamin D activation in A. fumigatus-elicited antifungal immunity in normal human airway epithelial cells. We found that A. fumigatus swollen conidia (SC) induced the expression of 1α-hydroxylase, the enzyme catalyzing the synthesis of active vitamin D, and vitamin D receptor (VDR) in 16HBE cells and led to increased local generation of active vitamin D. Locally activated vitamin D amplified SC-induced expression of antimicrobial peptides in 16HBE cells but attenuated SC-induced production of cytokines in an autocrine fashion. Furthermore, we identified β-glucan, the major A. fumigatus cell wall component, as the causative agent for upregulation of 1α-hydroxylase and VDR in 16HBE cells. Therefore, activation of vitamin D is inducible and provides a bidirectional regulation of the responses to A. fumigatus in 16HBE cells.

Vitamin D for the treatment of respiratory diseases: is it the end or just the beginning?

A large number of human, animal and in vitro studies have suggested that vitamin D3 (VD3) plays a critical role in inflammatory airway diseases such as asthma, chronic rhinosinusitis, and allergic rhinitis. VD3 acts upon a broad range of immune cells involved in the pathogenesis of these diseases including T-cells, dendritic cells (DCs), macrophages, and B-cells. In addition, VD3 can also regulate the functions of a number of non-immune cells including epithelial cells, fibroblasts, and smooth muscle cells. Given that VD3 has known effects on the immune system, it seems logical that supplementation with VD3 would prove efficacious in the treatment of these three diseases. While many studies, most of which are observational, have suggested that VD3 deficiency is associated with more severe disease, VD3 supplementation trials in humans have resulted in varied outcomes in terms of efficacy. In this review article we will discuss the role of VD3 in these three commonly associated respiratory diseases. We will explore the literature describing associations of VD3 deficiency with patient outcomes, cells in the respiratory microenvironment susceptible to VD3 regulation, conflicting results of VD3 supplementation trials, and potential gaps in our knowledge that may be limiting the widespread use of VD3 for the treatment of respiratory diseases such asthma, chronic rhinosinusitis and allergic rhinitis. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

Plasma 25-Hydroxyvitamin D Levels at Initiation of Care and Duration of Mechanical Ventilation in Critically Ill Surgical Patients

OBJECTIVE

Limited data exist regarding the relationship between plasma 25-hydroxyvitamin D levels and duration of respiratory support. Our goal was to explore whether vitamin D status at the time of intensive care unit (ICU) admission is associated with duration of mechanical ventilation in critically ill surgical patients.

MATERIALS AND METHODS

We analyzed data from a prospective cohort study involving 210 critically ill surgical patients. To explore the relationship between admission plasma 25-hydroxyvitamin D levels and duration of mechanical ventilation, we performed a Poisson regression while controlling for clinically relevant covariates. Only patients who required ≥48 hours of mechanical ventilation and survived ≥24 hours after discontinuation of respiratory support were included in the analytic cohort.

RESULTS

Ninety-four patients met inclusion criteria. Mean (standard deviation) plasma 25-hydroxyvitamin D level was 16 (7) ng/mL and median (interquartile range) duration of mechanical ventilation was 4 (2-7) days. Poisson regression analysis, adjusted for age, sex, race, body mass index, primary surgical service, Acute Physiology and Chronic Health Evaluation II score, and season of ICU admission, demonstrated an inverse association of plasma 25-hydroxyvitamin D levels with duration of mechanical ventilation (incident rate ratio per 10 ng/mL, 0.66; 95% confidence interval, 0.54-0.82).

CONCLUSIONS

In our cohort of critically ill surgical patients, plasma 25-hydroxyvitamin D levels measured on ICU admission were inversely associated with the duration of respiratory support. Randomized controlled trials are needed to assess whether vitamin D supplementation can influence duration of mechanical ventilation in surgical ICU patients.

Vitamin D for infections

PURPOSE OF REVIEW

Current data clearly support an interaction of vitamin D with cells of the immune system apart from its regulatory role in calcium homeostasis. The discovery that immune cells express the vitamin D receptor and are capable of metabolizing circulating 25-hydroxyvitamin D into its active form, 1,25-dihydroxyvitamin D, has revolutionized the field and suggested a regulatory role on both the innate and adaptive immune systems.

RECENT FINDINGS

Of particular interest with respect to infectious diseases, 1,25-dihydroxyvitamin D has been shown to trigger the production of antimicrobial peptides with a direct pathogen-killing capacity. Interestingly, pathogen-derived components influence the key players in the vitamin D metabolizing pathway, further supporting such an interaction.

SUMMARY

Here, we review the potential mechanisms of vitamin D in promoting the innate immune response against infectious agents and discuss the possible implications for such a response in the prevention of or the intervention in various infectious diseases.

Serum 25-hydroxyvitamin D levels and lung function in adults with asthma: the HUNT Study

The association between vitamin D status and lung function in adults with asthma remains unclear. We studied this cross-sectional association and possible modification by sex and allergic rhinitis in 760 adults (aged 19-55 years) with self-reported asthma in the Nord-Trøndelag Health Study. Serum 25-hydroxyvitamin D (25(OH)D) level <50 nmol·L(-1) was considered deficient. Lung function measurements included forced expiratory volume in 1 s (FEV1) % predicted, forced vital capacity (FVC) % predicted and FEV1/FVC ratio. Multiple linear regression models were used to estimate adjusted regression coefficients (β) and 95% confidence intervals. 44% of asthma adults had serum 25(OH)D levels <50 nmol·L(-1). Its associations with lung function measures seemed to be modified by sex and allergic rhinitis (p<0.03 for three-way interaction term). Overall, a serum 25(OH)D level <50 nmol·L(-1) was not associated with lung function measurements in subjects with allergic rhinitis in this asthma cohort. In men with asthma but without allergic rhinitis, however, a serum 25(OH)D level <50 nmol·L(-1) was significantly associated with lower FEV1/FVC ratio (β=-8.60%; 95% CI: -16.95%- -0.25%). Low serum 25(OH)D level was not associated with airway obstruction in most asthma adults with the exception of men with asthma but without allergic rhinitis.

A test of vitamin D benefits on respiratory health mediated through inflammatory markers

Previous studies have shown that vitamin D has beneficial effects on respiratory health. The role of inflammation as a possible mediator between vitamin D and respiratory health is not well understood. We used National Health and Nutrition Examination Survey 2001-2006 data (unweighted N = 12,856) to examine the mediating effects of biomarkers of inflammation on associations between vitamin D and respiratory health. Vitamin D was measured by serum 25 hydroxy vitamin D test. Respiratory health was measured by self-reported respiratory symptoms and chronic obstructive pulmonary disease (COPD). Biomarkers included C-reactive protein (CRP), alkaline phosphatase (AP), and five leukocyte measures. Models controlled for season, age, sex, race/ethnicity, body mass index, and current and former smoking. Lower levels of vitamin D were significantly associated with respiratory symptoms (linear trend p < 0.01) and with COPD (linear trend p < 0.0002) after adjusting for covariates. Adding biomarkers to the models to test for mediation, the vitamin D effect on respiratory health was not a consequence of any single marker but was partially attenuated as a combined result of leukocytes, AP, and CRP. Vitamin D is beneficial to improve respiratory health. Its benefits do not appear to be mediated by any single biomarker examined in this study; rather, benefits of vitamin D may act broadly through multiple mediating mechanisms.

Role of vitamin D3 in treatment of lumbar disc herniation--pain and sensory aspects: study protocol for a randomized controlled trial

BACKGROUND

Vitamin D receptors have been identified in the spinal cord, nerve roots, dorsal root ganglia and glial cells, and its genetic polymorphism association with the development of lumbar disc degeneration and herniation has been documented. Metabolic effects of active vitamin D metabolites in the nucleus pulposus and annulus fibrosus cells have been studied. Lumbar disc herniation is a process that involves immune and inflammatory cells and processes that are targets for immune regulatory actions of vitamin D as a neurosteroid hormone. In addition to vitamin D's immune modulatory properties, its receptors have been identified in skeletal muscles. It also affects sensory neurons to modulate pain. In this study, we aim to study the role of vitamin D3 in discogenic pain and related sensory deficits. Additionally, we will address how post-treatment 25-hydroxy vitamin D3 level influences pain and sensory deficits severity. The cut-off value for serum 25-hydroxy vitamin D3 that would be efficacious in improving pain and sensory deficits in lumbar disc herniation will also be studied.

METHODS/DESIGN

We will conduct a randomized, placebo-controlled, double-blind clinical trial. Our study population will include 380 cases with one-level and unilateral lumbar disc herniation with duration of discogenic pain less than 8 weeks. Individuals who do not have any contraindications, will be divided into three groups based on serum 25-hydroxy vitamin D3 level, and each group will be randomized to receive either a single-dose 300,000-IU intramuscular injection of vitamin D3 or placebo. All patients will be under conservative treatment. Pre-treatment and post-treatment assessments will be performed with the McGill Pain Questionnaire and a visual analogue scale. For the 15-day duration of this study, questionnaires will be filled out during telephone interviews every 3 days (a total of five times). The initial and final interviews will be scheduled at our clinic. After 15 days, serum 25-hydroxy vitamin D3 levels will be measured for those who have received vitamin D3 (190 individuals).

TRIAL REGISTRATION

Iranian Registry for Clinical Trials ID: IRCT2014050317534N1 (trial registration: 5 June 2014).

Evaluation of vitamin D level in patients from neurosurgical intensive care unit

Vitamin D plays an important role in maintaining normal bone metabolism. Recent studies have suggested that vitamin D influences many other physiological processes, including muscle function, cardiovascular homeostasis, nerve function, and immune response. Furthermore, accumulated evidence suggests that vitamin D also mediates the immune system response to infection. Critical neurosurgical patients have higher infection and mortality rates. To correlate vitamin D deficiency to the immunological status of neurosurgical intensive care unit patients, we detected serum vitamin D level in 15 patients with clinically suspected infection and 10 patients with confirmed infection. Serum level of 25-hydroxyvitamin D, the primary circulating form of vitamin D, was significantly decreased in patients with suspected or confirmed infection after a 2-week neurosurgical intensive care unit hospitalization, while serum level of 1,25-dihydroxyvitamin D, the active form of vitamin D, was significantly decreased in patients after a 4-week neurosurgical intensive care unit hospitalization. These findings suggest that vitamin D deficiency is linked to the immunological status of neurosurgical intensive care unit patients and vitamin D supplementation can improve patient's immunological status.

Serum vitamin D levels in children with recurrent tonsillopharyngitis

OBJECTIVE

In this study, we aimed to compare vitamin D levels of children with recurrent tonsillopharingitis and healthy controls, and investigate the relationship between sociodemographic characteristics and serum vitamin D levels.

METHODS

Children with recurrent tonsillopharingitis and healthy controls aged between 2, and 12 years who consulted to the outpatient clinics of Zeynep Kamil Maternity and Children's Diseases Training and Research Hospital from January to October 2012 were included in this study. Serum 25 (OH) vitamin D levels were studied by tandem mass spectroscopy (tandem ms) method. Risk factors which might be associated with vitamin D levels were questioned. Ethical aproval was obtained from the Ethics Committee of Zeynep Kamil Maternity and Children's Diseases Training and Research Hospital and informed consent from the parents of the children.

RESULTS

A total of 147 children; 74 (50.3%) patients and 73 (49.7%) controls were included in our study. Age, gender and demographic characteristics did not differ significantly between the two groups. Vitamin D levels in patients with recurrent tonsillopharingitis and controls were 19.7±8.7 ng/ml and 23.6±9.2 ng/ml, respectively (p<0.01). Although duration of vitamin D usage was shorter in children with recurrent tonsillopharingitis, this difference was not statistically significant (p>0.05).

CONCLUSION

Vitamin D levels in children with ≥7 recurrent episodes of tonsillophargitis within the preceeding year were significantly lower compared to the control group. We believe that serum vitamin D levels should be checked in children with recurrent tonsillopharingitis and deficiencies should be treated.

Vitamin D deficiency causes defective resistance to Aspergillus fumigatus in mice via aggravated and sustained inflammation

Background

Vitamin D plays an important role in pulmonary resistance and immunity, and its deficiency has been linked to various respiratory infections. Little is known about the effect of vitamin D deficiency on host pulmonary defense to Aspergillus fumigatus (A. fumigatus).

Methods

Mice raised on vitamin D sufficient or deficient diets were infected intratracheally with A. fumigatus conidia. Mortality, fungal growth, weight loss and lung histology were monitored. Alveolar macrophages (AMs) were stimulated with A. fumigatus conidia in vitro. The kinetics of pro-inflammatory cytokines (TNF-α, IL-1β and IL-6), chemokines (CXCL1, CCL3), and pattern recognition receptors (Toll-like receptor [TLR] 2, TLR 4 and dectin-1) expression in the lungs and AMs were measured.

Results

Upon A. fumigatus infection, vitamin D deficient mice showed higher mortality, greater fungal load, and more weight loss than its sufficient counterparts. Vitamin D deficient mice demonstrated aggravated and prolonged histological evidence of lung inflammation as well as enhanced BAL cell counts, dominated by neutrophils after A. fumigatus inoculation. Increased basal levels of pro-inflammatory cytokines in the lungs and AMs from naïve vitamin D deficient mice were observed. Upon A. fumigatus exposure, vitamin D deficiency led to enhanced and sustained expression of TNF-α, IL-1β, IL-6, CXCL1 and CCL3 both in vivo and in vitro. Up-regulation of TLR2, TLR4 and dectin-1was observed in the lungs and AMs from vitamin D deficient mice both at baseline and after A. fumigatus exposure.

Conclusions

Vitamin D deficiency causes defective pulmonary resistance to A. fumigatus in mice, possibly by the enhanced basal expression of pattern recognition receptors and pro-inflammatory cytokines, which induced excessive inflammatory response in response to A. fumigatus challenge.

Vitamin D deficiency and level of asthma control in women from North of Jordan: a case-control study

INTRODUCTION

Reduced vitamin-D levels in patients with asthma have been associated with impaired lung function, increased airway hyper-responsiveness, and reduced glucocorticoid responsiveness. Nationwide studies revealed a considerable prevalence of vitamin-D deficiency (VDD) in Jordanian women.

OBJECTIVE

A case-control study was conducted to determine the relationship between serum vitamin A and D levels and asthma among women in North of Jordan.

METHODS

Sixty-eight asthmatics, age range between 14 and 65 years and 77 healthy women, age range between 19 and 51 years, were enrolled. Asthma severity was classified using Global Initiative for Asthma (GINA) guidelines and Asthma Control Test (ACT) questionnaire. Serum vitamin-A and 25-hydroxyvitamin-D (25(OH)D3) levels were measured using high-performance liquid chromatography (HPLC) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods, respectively.

RESULTS

The prevalence of VDD (<15 ng/ml) was higher but not statistically significant for women with asthma compared with controls (95.6% vs. 87.0%; p = 0.070). The severity of VDD correlated with the number of asthma medications (p = 0.020). 25(OH)-D3 serum levels directly correlated with asthma control level using ACT score (p = 0.012) and GINA classification (p = 0.046). After adjusting for age, the odds of having VDD for asthmatic women were 35.9 times higher than that for women with no asthma. There was no difference in serum vitamin-A level between healthy and asthmatic women (p = 0.214) and none had vitamin-A deficiency (<200 µg/dl).

CONCLUSIONS

VDD is prevalent in women with asthma in northern Jordan. The severity of VDD correlated with poor asthma control and a need for more medications to control asthma. There was no association between vitamin-A and asthma.

Vitamin D treatment improves survival and infant lung structure after intra-amniotic endotoxin exposure in rats: potential role for the prevention of bronchopulmonary dysplasia

Vitamin D (vit D) has anti-inflammatory properties and modulates lung growth, but whether vit D can prevent lung injury after exposure to antenatal inflammation is unknown. We hypothesized that early and sustained vit D treatment could improve survival and preserve lung growth in an experimental model of bronchopulmonary dysplasia induced by antenatal exposure to endotoxin (ETX). Fetal rats (E20) were exposed to ETX (10 μg), ETX + Vit D (1 ng/ml), or saline (control) via intra-amniotic (IA) injections and delivered 2 days later. Newborn pups exposed to IA ETX received daily intraperitoneal injections of vit D (1 ng/g) or saline for 14 days. Vit D treatment improved oxygen saturations (78 vs. 87%; P < 0.001) and postnatal survival (84% vs. 57%; P < 0.001) after exposure to IA ETX compared with IA ETX alone. Postnatal vit D treatment improved alveolar and vascular growth at 14 days by 45% and 25%, respectively (P < 0.05). Vit D increased fetal sheep pulmonary artery endothelial cell (PAEC) growth and tube formation by 64% and 44%, respectively (P < 0.001), and prevented ETX-induced reductions of PAEC growth and tube formation. Vit D directly increased fetal alveolar type II cell (ATIIC) growth by 26% (P < 0.001) and enhanced ATIIC growth in the presence of ETX-induced growth suppression by 73% (P < 0.001). We conclude that antenatal vit D therapy improved oxygenation and survival in newborn rat pups and enhanced late lung structure after exposure to IA ETX in vivo, which may partly be due to direct effects on vascular and alveolar growth.

Vitamin D binding protein: a multifunctional protein of clinical importance

Since the discovery of group-specific component and its polymorphism by Hirschfeld in 1959, research has put spotlight on this multifunctional transport protein (vitamin D binding protein, DBP). Besides the transport of vitamin D metabolites, DBP is a plasma glycoprotein with many important functions, including sequestration of actin, modulation of immune and inflammatory responses, binding of fatty acids, and control of bone development. A considerable DBP polymorphism has been described with a specific allele distribution in different geographic area. Multiple studies have shed light on the interesting relationship between polymorphisms of the DBP gene and the susceptibility to diseases. In this review, we give an overview of the multifunctional character of DBP and describe the clinical importance of DBP and its polymorphisms. Finally, we discuss the possibilities to use DBP as a novel therapeutic agent.

The prevalence of vitamin D deficiency in children in the Northern Territory

AIMS

The primary aim of this study was to determine the frequency of vitD deficiency/insufficiency in an opportunistic sample of Northern Territory (NT) children. The secondary aim was to evaluate whether: (i) 25(OH)vitD (25(OH)D) levels differ between Indigenous/non-Indigenous children; and (ii) VitD insufficiency is associated with increased acute/infective hospitalisations.

METHODS

Twenty-five (OH)D levels were measured in 98 children <16 years between August 2011 and January 2012 (children hospitalised acutely/non-acutely and well children from other studies based in Darwin). VitD deficiency was defined as 25(OH)D < 50 nmol/L, and insufficiency was postulated to be <75 nmol/L. Demographic data were collected, and computer records were reviewed.

RESULTS

Median age was 59 months (range 2-161); 3.1% were vitD deficient, 19.4% insufficient. There was no significant difference in mean 25(OH)D level between Indigenous (93.2, standard deviation (SD) 21.9, n = 42) and non-Indigenous (97.3, SD 27.9, n = 56) children (P = 0.32). Median number of hospitalisations/year were similar (P = 0.319) between vitD sufficient (0.34, range 0-12, n = 76) and insufficient (0.22, 0-6, n = 22) children. There was no significant difference between number of infective admissions per year between vitD sufficient/insufficient groups (P = 0.119).

CONCLUSIONS

Compared with US data (19% deficient, 65% insufficient) fewer NT children are vitD deficient/insufficient. In our limited sample, being vitD insufficient was not associated with increased acute/infective hospitalisations, but a larger unbiased sample of NT children is needed. More information is needed about the optimum level of vitD for non-bone-related health in children.

Vitamin D status and community-acquired pneumonia: results from the third National Health and Nutrition Examination Survey

OBJECTIVE

To investigate the association between serum 25-hydroxyvitamin D [25(OH)D] level and history of community-acquired pneumonia (CAP).

PATIENTS AND METHODS

We identified 16,975 individuals (≥17 years) from the third National Health and Nutrition Examination Survey (NHANES III) with documented 25(OH)D levels. To investigate the association of 25(OH)D with history of CAP in these participants, we developed a multivariable logistic regression model, adjusting for demographic factors (age, sex, race, poverty-to-income ratio, and geographic location), clinical data (body mass index, smoking status, asthma, chronic obstructive pulmonary disease, congestive heart failure, diabetes mellitus, stroke, chronic kidney disease, neutropenia, and alcohol consumption), and season. Locally weighted scatterplot smoothing (LOWESS) was used to depict the relationship between increasing 25(OH)D levels and the cumulative frequency of CAP in the study cohort.

RESULTS

The median [interquartile range (IQR)] serum 25(OH)D level was 24 (IQR 18-32) ng/mL. 2.1% [95% confidence interval (CI): 1.9-2.3] of participants reported experiencing a CAP within one year of their participation in the national survey. After adjusting for demographic factors, clinical data, and season, 25(OH)D levels <30 ng/mL were associated with 56% higher odds of CAP [odds ratio 1.56; 95% confidence interval: 1.17-2.07] compared to levels ≥30 ng/mL. LOWESS analysis revealed a near linear relationship between vitamin D status and the cumulative frequency of CAP up to 25(OH)D levels around 30 ng/mL.

CONCLUSION

Among 16,975 participants in NHANES III, 25(OH)D levels were inversely associated with history of CAP. Randomized controlled trials are warranted to determine the effect of optimizing vitamin D status on the risk of CAP.

Diet and vitamin D as risk factors for lung impairment and COPD

Epidemiologic and observational studies have shown an association between increased intakes of certain micronutrients and higher levels of lung function and health. The National Health and Nutrition Examination Surveys of the U.S. population have demonstrated repeatedly that increased intakes or serum levels of some micronutrients, including the vitamins E, D, C, and A, and carotenes are associated positively with forced expiratory volume in 1 second (FEV1). These findings are complemented by other observational studies, including the MORGEN study as well as the Seven Countries Study, both of which found micronutrient status had positive correlations with pulmonary function. In addition, epidemiologic studies have demonstrated that dietary intake patterns with increased intakes of fruit, vegetables, fish, vitamin E, and whole grains have been associated with a decreased development of chronic obstructive pulmonary disease (COPD) in smokers and nonsmokers, higher levels of FEV1, and decreased long-term COPD mortality. Diets high in refined food have been associated with accelerated longitudinal decline in FEV1 over 5 years. Taken together, these results suggest that micronutrient status may impact lung function, and that nutrition interventions could be a useful tool in a public health campaign aimed at the prevention of lung disease. Future research should focus on the effect of nutrition interventions on the natural history of lung disease.

Plasma 25-hydroxyvitamin D associated with pulmonary function in Canadian adults with excess adiposity

BACKGROUND

Vitamin D deficiency is an important health issue, particularly among people residing in northern countries. Low concentrations of 25-hydroxyvitamin D [25(OH)D] have been linked to several health conditions.

OBJECTIVE

The objective was to determine the association between plasma 25(OH)D and pulmonary function and the effect modifications of sex and body mass index (BMI) in adults.

DESIGN

A cross-sectional study included 3359 adults aged ≥18 y who participated in the Canadian Health Measures Survey, and a 2-stage multiple linear regression analysis was conducted.

RESULTS

Overall, 26% of the adults had a plasma 25(OH)D concentration <50 nmol/L, which is considered deficient (ie, hypovitaminosis D). This deficiency was more prevalent among men than among women (30% compared with 23%). Regression analysis showed that deficient plasma 25(OH)D was associated with lower mean residual forced vital capacity and forced expiratory volume in 1 s in men after adjustment for covariates. When further stratified by BMI, the associations were more marked in overweight and obese men. Vitamin D deficiency associated with pulmonary function was not statistically significant in normal-weight men or in women, regardless of BMI categories. Similar results were obtained when plasma 25(OH)D was examined as a continuous variable in the models.

CONCLUSIONS

Hypovitaminosis D may be a risk factor for lung dysfunction, especially for overweight and obese men. Further research is necessary to determine the mechanism of the interrelation between vitamin D, adiposity, and pulmonary function.

Modeling the influence of vitamin D deficiency on cigarette smoke-induced emphysema

Chronic obstructive pulmonary disease (COPD) is a major cause of morbidity and mortality worldwide. While the primary risk factor for COPD is cigarette smoke exposure, vitamin D deficiency has been epidemiologically implicated as a factor in the progressive development of COPD-associated emphysema. Because of difficulties inherent to studies involving multiple risk factors in the progression of COPD in humans, we developed a murine model in which to study the separate and combined effects of vitamin D deficiency and cigarette smoke exposure. During a 16-week period, mice were exposed to one of four conditions, control diet breathing room air (CD-NS), control diet with cigarette smoke exposure (CD-CSE), vitamin D deficient diet breathing room air (VDD-NS) or vitamin D deficient diet with cigarette smoke exposure (VDD-CSE). At the end of the exposure period, the lungs were examined by a pathologist and separately by morphometric analysis. In parallel experiments, mice were anesthetized for pulmonary function testing followed by sacrifice and analysis. Emphysema (determined by an increase in alveolar mean linear intercept length) was more severe in the VDD-CSE mice compared to control animals and animals exposed to VDD or CSE alone. The VDD-CSE and the CD-CSE mice had increased total lung capacity and increased static lung compliance. There was also a significant increase in the matrix metalloproteinase-9: tissue inhibitor of metalloproteinases-1 (TIMP-1) ratio in VDD-CSE mice compared with all controls. Alpha-1 antitrypsin (A1AT) expression was reduced in VDD-CSE mice as well. In summary, vitamin D deficiency, when combined with cigarette smoke exposure, seemed to accelerate the appearance of emphysemas, perhaps by virtue of an increased protease-antiprotease ratio in the combined VDD-CSE animals. These results support the value of our mouse model in the study of COPD.

Effects of vitamin D on immune disorders with special regard to asthma, COPD and autoimmune diseases: a short review

This paper reviews the recent data on the role of vitamin D (VD) in the genesis of various immunological disorders. It inhibits immune reactions in general, but it enhances the transcription of 'endogenous antibiotics' such as cathelicidin and defensins. VD inhibits the genesis of both Th1- and Th2-cell mediated diseases. The pleiotropic character VD-induced effects are due to the altered transcription of hundreds of genes. VD supplementation in most related studies reduced the prevalence of asthma. Th1-dependent autoimmune diseases (e.g., multiple sclerosis, Type 1 diabetes, Crohn's disease, rheumatoid arthritis and so on) are also inhibited by VD due to inhibition of antigen presentation, reduced polarization of Th0 cells to Th1 cells and reduced production of cytokines from the latter cells. VD seems to also be a useful adjunct in the prevention of allograft rejection. Last but not least, VD supplementation may be useful in the prevention or adjunct treatment of chronic obstructive pulmonary disease.

Vitamin D to prevent acute lung injury following oesophagectomy (VINDALOO): study protocol for a randomised placebo controlled trial

Background

Acute lung injury occurs in approximately 25% to 30% of subjects undergoing oesophagectomy. Experimental studies suggest that treatment with vitamin D may prevent the development of acute lung injury by decreasing inflammatory cytokine release, enhancing lung epithelial repair and protecting alveolar capillary barrier function.

Methods/Design

The ‘Vitamin D to prevent lung injury following oesophagectomy trial’ is a multi-centre, randomised, double-blind, placebo-controlled trial. The aim of the trial is to determine in patients undergoing elective transthoracic oesophagectomy, if pre-treatment with a single oral dose of vitamin D₃ (300,000 IU (7.5 mg) cholecalciferol in oily solution administered seven days pre-operatively) compared to placebo affects biomarkers of early acute lung injury and other clinical outcomes. The primary outcome will be change in extravascular lung water index measured by PiCCO® transpulmonary thermodilution catheter at the end of the oesophagectomy. The trial secondary outcomes are clinical markers indicative of lung injury: PaO₂:FiO₂ ratio, oxygenation index; development of acute lung injury to day 28; duration of ventilation and organ failure; survival; safety and tolerability of vitamin D supplementation; plasma indices of endothelial and alveolar epithelial function/injury, plasma inflammatory response and plasma vitamin D status. The study aims to recruit 80 patients from three UK centres.

Discussion

This study will ascertain whether vitamin D replacement alters biomarkers of lung damage following oesophagectomy.

Trial registration

Current Controlled Trials ISRCTN27673620

Serum vitamin D levels in children with recurrent otitis media

The aims of this study were to evaluate serum vitamin D levels in cases of recurrent otitis media and investigate the effect of vitamin D therapy on the risk of re-occurrence of the disease. This prospective study was performed by comparing serum vitamin D levels in children with recurrent otitis media and healthy children. Eighty-four children between 1 and 5 years of age and diagnosed with recurrent otitis media were enrolled as the study group. One hundred-and-eight healthy children with similar demographic characteristics were enrolled as the control group. Patients were divided into groups according to their serum 25(OH) vitamin D levels. In patients with low initial serum vitamin D levels, vitamin D therapy was administered in addition to conventional treatment for otitis media. Mean serum 25(OH) vitamin D level in the study group was 11.4 ± 9.8 ng/mL Serum 25(OH) vitamin D levels were below 20 ng/mL in 69 % (n = 58) of cases in this group. In the control group, mean serum 25(OH) vitamin D level was 29.2 ± 13.9 ng/mL and was below 20 ng/mL in 30 % (n = 32) of cases. Comparison of serum 25(OH) vitamin D levels and PTH in the study and control groups revealed a statistically significant difference (p < 0.05). Treatment was initiated in cases diagnosed with vitamin D deficiency, and patients were followed up in due course. The only episodes detected over the course of 1-year follow-up were one attack in five patients and two attacks in two. We believe that co-administration of supplementary vitamin D together with conventional treatments is appropriate in the management of upper respiratory infections such as otitis media.

Prevalence of hypovitaminosis D among children with upper extremity fractures

BACKGROUND

Recent publications show a high rate of hypovitaminosis D among children in general as well as among children with fractures. 25-hydroxyvitamin D levels were analyzed from hospital records to determine the prevalence of hypovitaminosis D, with the goal of using that information in fracture management and nutritional counseling.

METHODS

We retrospectively reviewed the records of 213 children with upper extremity fractures that were treated during a 14-month period. For 181 of those patients, the 25-hydroxyvitamin D level was measured at the time of emergency department presentation or at the first clinic appointment within 2 weeks after the initial presentation. The following information was collected from the charts: fracture mechanism (high or low energy), age, sex, race, and body mass index. Vitamin D levels were categorized as normal (≥ 32 ng/mL), insufficient (20 to 32 ng/mL), or deficient (< 20 ng/mL). The levels were analyzed with respect to fracture pattern and race.

RESULTS

Of the 181 patients, 24% had deficient vitamin D levels, 41% had insufficient levels, and 35% had normal levels. There was no significant correlation with vitamin D level and mechanism of injury. African American children were more likely to have insufficient or deficient levels of vitamin D.

CONCLUSIONS

Hypovitaminosis D is common among children with upper extremity fractures. Further investigation is warranted on the use of the 25-hydroxyvitamin D level as a screening tool to predict risk of fracture and to design proper nutritional programs for children with fractures.

LEVEL OF EVIDENCE

Retrospective chart review; Level III evidence.

Cord blood 25-hydroxyvitamin D levels and the risk of acute lower respiratory tract infection in early childhood

OBJECTIVE

To determine the relationship between cord blood 25-hydroxyvitamin D [25 (OH) D] concentrations and the subsequent risk of acute lower respiratory tract infection (ALRI) in the first 2 years of life.

PATIENTS AND METHODS

Cord blood from 206 newborns was tested for 25 (OH) D. Medical records covering the first 2 years of life were reviewed, and the diagnosis of ALRI was recorded.

RESULTS

Sixty-two (30.1%) infants developed ALRI in their first 2 years of life, of whom 49 (79%) infants had bronchiolitis and 13 (21%) infants had pneumonia. Concentrations of 25 (OH) D were lower in infants who developed ALRI compared with those did not (p < 0.0001). Vitamin D deficiency was associated with increased risk of ALRI (p = 0.000).

CONCLUSION

Low cord blood 25 (OH) D levels are associated with increased risk of ALRI in the first 2 years of life.

Vitamin d deficiency in e.N.T. Patients

A prospective study to observe the prevalence of deficiency of vitamin D in out patients of otolaryngology clinic at Indian Institute of ear diseases, Muzaffarnagar. The patients attending outpatient of otolaryngology clinic with various complaints and not responding to conventional treatment were advised for assessment of vitamin D [25 (OH)D] level in blood. The age, sex, occupation, colour of skin, chief complaints, obesity, provisional diagnosis, and incidence of sun exposure was noted in all cases. A total of 86 patients were examined, maximum patients were in the age group of 7-15 years. The chief complaints in majority of the patients were sore throat with recurrent upper respiratory tract infection. Only in three patient's vitamin D level was found to be with in normal limits. In rest 83 (96.51 %) it was either deficient 57 (66.28 %) or insufficient 21 (24.42 %). The incidence of vitamin D deficiency is extremely common in Ear Nose Throat disease (E.N.T.) patients. The results of vitamin supplementation were promising in cases of benign paroxysmal positional vertigo with cervical spondylosis and URTI with asthma, empirical supplementation of vitamin D in all E.N.T. patients not responding to conventional treatment is worth trying. At place of sun screen, use of pomegranates and blueberries may be encouraged to prevent sunburn and eliminate Vitamin D deficiency.

Inhibition of vitamin d receptor translocation by cigarette smoking extracts

Background

Vitamin D can translocate a vitamin D receptor (VDR) from the nucleus to the cell membranes. The meaning of this translocation is not elucidated in terms of a role in pathogenesis of chronic obstructive pulmonary disease (COPD) till now. VDR deficient mice are prone to develop emphysema, suggesting that abnormal function of VDR might influence a generation of COPD. The blood levels of vitamin D have known to be well correlated with that of lung function in patients with COPD, and smoking is the most important risk factor in development of COPD. This study was performed to investigate whether cigarette smoke extracts (CSE) can inhibit the translocation of VDR and whether mitogen activated protein kinases (MAPKs) are involved in this inhibition.

Methods

Human alveolar basal epithelial cell line (A549) was used in this study. 1,25-(OH₂)D₃ and/or MAPKs inhibitors and antioxidants were pre-incubated before stimulation with 10% CSE, and then nucleus and microsomal proteins were extracted for a Western blot of VDR.

Results

Five minutes treatment of 1,25-(OH₂)D₃ induced translocation of VDR from nucleus to microsomes by a dose-dependent manner. CSE inhibited 1,25-(OH₂)D₃-induced translocation of VDR in both concentrations of 10% and 20%. All MAPKs inhibitors did not suppress the inhibitory effects of CSE on the 1,25-(OH₂)D₃-induced translocation of VDR. Quercetin suppressed the inhibitory effects of CSE on the 1,25-(OH₂)D₃-induced translocation of VDR, but not in n-acetylcysteine.

Conclusion

CSE has an ability to inhibit vitamin D-induced VDR translocation, but MAPKs are not involved in this inhibition.

Role of vitamin D-binding protein in isocyanate-induced occupational asthma

The development of a serological marker for early diagnosis of isocyanate-induced occupational asthma (isocyanate-OA) may improve clinical outcome. Our previous proteomic study found that expression of vitamin D-binding protein (VDBP) was upregulated in the patients with isocyanate-OA. In the present study, we evaluated the clinical relevance of VDBP as a serological marker in screening for isocyanate-OA among exposed workers and its role in the pathogenesis of isocyanate-OA. Three study groups including 61 patients with isocyanate-OA (group I), 180 asymptomatic exposed controls (AECs, group II), 58 unexposed healthy controls (NCs, group III) were enrolled in this study. The baseline serum VDBP level was significantly higher in group I compared with groups II and III. The sensitivity and specificity for predicting the phenotype of isocyanate-OA with VDBP were 69% and 81%, respectively. The group I subjects with high VDBP (≥ 311 µg/ml) had significantly lower PC₂₀ methacholine levels than did subjects with low VDBP. The in vitro studies showed that TDI suppressed the uptake of VDBP into RLE-6TN cells, which was mediated by the downregulation of megalin, an endocytic receptor of the 25-hydroxycholecalciferol-VDBP complex. Furthermore, toluene diisocyanate (TDI) increased VEGF production and secretion from this epithelial cells by suppression of 1,25-dihydroxycholecalciferol [1,25(OH)₂D₃] production. The findings of this study suggest that the serum VDBP level may be used as a serological marker for the detection of isocyanate-OA among workers exposed to isocyanate. The TDI-induced VEGF production/secretion was reversed by 1,25(OH)₂D₃ treatment, which may provide a potential therapeutic strategy for patients with isocyanate-OA.

Vitamin D and influenza

Vitamin D has become increasingly recognized in the literature for its extra-skeletal roles, including an effect on inflammation and the immune response to infection. Our goal was to describe the role of vitamin D in the immune response and implications for the risk of influenza infection in humans. In this review, we first consider literature that provides molecular and genetic support to the idea that vitamin D is related to the adaptive and innate immune responses to influenza infection in vitro and in animal models. We then discuss observational studies and randomized controlled trials of vitamin D supplementation in humans. Finally, we consider some of the knowledge gaps surrounding vitamin D and immune response that must be filled.

Invasive pneumonia and septic shock in infants as a presentation of cystic fibrosis with vitamin-deficiency

Herein we describe three infants with the rare presentation of pneumonia with septic shock as their initial medical encounter leading to the diagnosis of cystic fibrosis (CF). At the time of their presentation all three children had significant nutritional deficiency. We initiated an aggressive treatment regimen including nutritional supplementation which resulted in improvement in their pulmonary status and no further recurrences. This series highlights the possible presentation of CF in infancy as a life-threatening invasive infection of Staphylococcus aureus or Pseudomonas aeruginosa. It also supports neonatal screening and emphasizes the role of early attention to nutritional status and vitamin supplementation.

Clinical review: Early treatment of acute lung injury--paradigm shift toward prevention and treatment prior to respiratory failure

Acute lung injury (ALI) remains a major cause of morbidity and mortality in critically ill patients. Despite improved understanding of the pathogenesis of ALI, supportive care with a lung protective strategy of mechanical ventilation remains the only treatment with a proven survival advantage. Most clinical trials in ALI have targeted mechanically ventilated patients. Past trials of pharmacologic agents may have failed to demonstrate efficacy in part due to the resultant delay in initiation of therapy until several days after the onset of lung injury. Improved early identification of at-risk patients provides new opportunities for risk factor modification to prevent the development of ALI and novel patient groups to target for early treatment of ALI before progression to the need for mechanical ventilation. This review will discuss current strategies that target prevention of ALI and some of the most promising pharmacologic agents for early treatment of ALI prior to the onset of respiratory failure that requires mechanical ventilation.

Effects of seasonal vitamin D deficiency and respiratory acidosis on bone metabolism markers in submarine crewmembers during prolonged patrols

The aim of the study was to determine the seasonal influence of vitamin D status on bone metabolism in French submariners over a 2-mo patrol. Blood samples were collected as follows: prepatrol and patrol days 20, 41, and 58 on crewmembers from both a winter (WP; n = 20) and a summer patrol (SP; n = 20), respectively. Vitamin D status was evaluated for WP and SP. Moreover, extended parameters for acid-base balance (Pco2, pH, and bicarbonate), bone metabolism (bone alkaline phosphatase and COOH-terminal telopeptide of type I collagen), and mineral homeostasis (parathyroid hormone, ionized calcium and phosphorus) were scrutinized. As expected, SP vitamin D status was higher than WP vitamin D status, regardless of the considered experimental time. A mild chronic respiratory acidosis (CRA) was identified in both SP and WP submariners, up to patrol day 41. Such an occurrence paired up with an altered bone remodeling coupling (decreased bone alkaline phosphatase-to-COOH-terminal telopeptide of type I collagen ratio). At the end of the patrol ( day 58), a partial compensation of CRA episode, combined with a recovered normal bone remodeling coupling, was observed in SP, not, however, in WP submariners. The mild CRA episode displayed over the initial 41-day submersion period was mainly induced by a hypercapnia resulting from the submarine-enriched CO2 level. The correlated impaired bone remodeling may imply a physiological attempt to compensate this acidosis via bone buffering. On patrol day 58, the discrepancy observed in terms of CRA compensation between SP and WP may result from the seasonal influence on vitamin D status.

Extraskeletal benefits and risks of calcium, vitamin D and anti-osteoporosis medications

Drugs used for the prevention and the treatment of osteoporosis exert various favourable and unfavourable extra-skeletal effects whose importance is increasingly recognized notably for treatment selection.

INTRODUCTION

The therapeutic armamentarium for the prevention and the treatment of osteoporosis is increasingly large, and possible extra-skeletal effects of available drugs could influence the choice of a particular compound.

METHODS

The present document is the result of a national consensus, based on a systematic and critical review of the literature.

RESULTS

Observational research has suggested an inverse relationship between calcium intake and cardiovascular diseases, notably through an effect on blood pressure, but recent data suggest a possible deleterious effect of calcium supplements on cardiovascular risk. Many diverse studies have implicated vitamin D in the pathogenesis of clinically important non-skeletal functions or diseases, especially muscle function, cardiovascular disease, autoimmune diseases and common cancers. The possible effects of oral or intravenous bisphosphonates are well-known. They have been associated with an increased risk of oesophageal cancer or atrial fibrillation, but large-scale studies have not found any association with bisphosphonate use. Selective oestrogen receptor modulators have demonstrated favourable or unfavourable extra-skeletal effects that vary between compounds. Strontium ranelate has a limited number of non-skeletal effects. A reported increase in the risk of venous thromboembolism is not found in observational studies, and very rare cases of cutaneous hypersensitivity reactions have been reported. Denosumab has been introduced recently, and its extra-skeletal effects still have to be assessed.

CONCLUSION

Several non-skeletal effects of bone drugs are well demonstrated and influence treatment choices.

Vitamin d status in patients with chronic obstructive pulmonary disease who participate in pulmonary rehabilitation

PURPOSE

Vitamin D deficiency is common in patients with chronic obstructive pulmonary disease; however, no study has evaluated the influence of vitamin D status on effects of pulmonary rehabilitation (PR).

METHODS

We studied 311 patients, who participated in a 7-week outpatient PR. Vitamin D status was assessed at entry and examined for association with patient characteristics, dropout from PR, and effect on endurance shuttle walk time.

RESULTS

Vitamin D level 25 nM was seen in 61 (19.6%) of the patients. They were significantly younger, were more frequently on long-term oxygen therapy, had higher body mass index and fat-free mass index, had worse quality of life score, tended to have lower percent predicted value for forced expiratory volume in the first second of expiration, and more frequently were current smokers. They had a 3-time higher risk of dropout from the PR program (P = .003) compared with patients with normal vitamin D status and a poorer improvement in endurance shuttle walk time (P = .03).

DISCUSSION

In conclusion, vitamin D deficiency was significantly associated with higher dropout rates from PR, and there was a tendency toward a poorer improvement in endurance shuttle walk time.

Serum micronutrient concentrations and childhood asthma: the PIAMA birth cohort study

BACKGROUND

Research suggests an influence of micronutrients on childhood asthma. So far, evidence mainly originates from cross-sectional studies using nutrient intake data, which is not an accurate measure of nutrient status. This study aimed to investigate the cross-sectional and prospective associations between serum concentrations of magnesium, vitamin D, selenium, and zinc and prevalence of (severe) asthma, atopy, and bronchial hyperresponsiveness (BHR) in childhood.

METHODS

In the Prevention and Incidence of Asthma and Mite Allergy birth cohort study, serum nutrient concentrations were available for a 4-yr-old subgroup (n = 372) and for a different 8-yr-old subgroup (n = 328). Yearly questionnaires inquired about asthma prevalence until 8 yr of age. Allergic sensitization was measured at 4 and 8 yr of age; BHR was measured at 8 yr of age. Data were analyzed with logistic regression and generalized estimating equations models.

RESULTS

There was a consistent (non-significant) inverse association between serum magnesium concentrations and asthma prevalence. Serum vitamin D concentrations measured at age 4 were inversely associated with asthma at ages 4-8 [e.g., cross-sectional association between vitamin D tertile 3 vs. 1 and severe asthma: odds ratio (OR): 0.49, 95% confidence interval (CI): 0.25-0.95], whereas vitamin D measured at age 8 was positively associated with asthma at age 8 (e.g., cross-sectional association between vitamin D tertile 3 vs. 1 and severe asthma: OR: 2.14, 95% CI: 0.67-6.82).

CONCLUSIONS

Our study contributes to the evidence that children with higher serum magnesium concentrations are less likely to have asthma. The associations between serum vitamin D concentrations and asthma were age-dependent.

Apparent temperature and air pollution vs. elderly population mortality in Metro Vancouver

Background

Meteorological conditions and air pollution in urban environments have been associated with general population and elderly mortality, showing seasonal variation.

Objectives

This study is designed to evaluate the relationship between apparent temperature (AT) and air pollution (PM_2.5) vs. mortality in elderly population of Metro Vancouver.

Methods

Statistical analyses are performed on moving sum daily mortality rates vs. moving average AT and PM_2.5 in 1-, 2-, 3-, 5-, and 7-day models for all seasons, warm temperatures above 15°C, and cold temperatures below 10°C.

Results

Approximately 37% of the variation in all-season mortality from circulatory and respiratory causes can be explained by the variation in 7-day moving average apparent temperature (r² = 0.37, p<0.001). Although the analytical results from air pollution models show increasingly better prediction ability of longer time-intervals (r² = 0.012, p<0.001 in a 7-day model), a very weak negative association between elderly mortality and air pollution is observed.

Conclusions

Apparent temperature is associated with mortality from respiratory and circulatory causes in elderly population of Metro Vancouver. In a changing climate, one may anticipate to observe potential health impacts from the projected high- and particularly from the low-temperature extremes.

Low concentrations of serum 25-hydroxyvitamin D associated with increased risk for chronic bronchitis among US adults

Increasing evidence suggests that vitamin D benefits both innate and adaptive immunity, thereby eliciting an anti-inflammatory effect and reducing the risk of infectious disease. The present study examined the association between serum 25-hydroxyvitamin D (25(OH)D) levels and the risk of chronic bronchitis among US adults. We analysed data from 6872 US adults aged ≥ 20 years who participated in the 2003-6 National Health and Nutrition Examination Survey. Prevalence and OR with 95 % CI of having self-reported chronic bronchitis were estimated by quintiles of 25(OH)D or vitamin D-deficiency status after adjustment for potential confounders. The results showed that the adjusted prevalence of chronic bronchitis ranged from 2.4 (95 % CI 1.4, 3.3) % among adults in the highest quintile of 25(OH)D ( ≥ 30 ng/ml) to 4.1 (95 % CI 2.5, 5.6) % among adults in the lowest quintile ( < 15 ng/ml; P for trend < 0.01). The adjusted OR for chronic bronchitis was 1.85 (95 % CI 1.06, 3.24) in adults with < 15 ng/ml 25(OH)D and 1.77 (95 % CI 1.19, 2.65) in those with 15 to < 20 ng/ml 25(OH)D compared with adults with ≥ 30 ng/ml 25(OH)D. Additionally, the adjusted OR for chronic bronchitis was 1.52 (95 % CI 1.03, 2.26) among adults with vitamin D deficiency ( < 20 ng/ml 25(OH)D) compared with those with ≥ 20 ng/ml 25(OH)D. For every 1 ng/ml increase in 25(OH)D, the likelihood of having chronic bronchitis fell by 2.6 % (P = 0.016). In conclusion, low serum 25(OH)D levels are associated with the increased risk of chronic bronchitis among US adults. The present results provide support for continuing research on the role of vitamin D in lung diseases.

An effective oral vitamin D replacement therapy in persons with spinal cord injury

BACKGROUND/OBJECTIVE

Vitamin D deficiency is prevalent in chronic spinal cord injury (SCI). A 3-month course of oral vitamin D(3) to 'normalize' serum vitamin D levels was investigated.

DESIGN

Prospective drug-intervention study.

SETTING

VA Medical Center; private rehabilitation facility.

METHODS

Seven individuals with chronic SCI and vitamin D deficiency completed 3 months of oral vitamin D(3) (i.e. cholecalciferol) supplementation. At screening, baseline, and months 1 and 3, blood was collected for serum calcium, 25 hydroxyvitamin D [25(OH)D], intact parathyroid hormone (iPTH), and N-telopeptide (NTx); 24-hour urine for calcium, creatinine, and NTx was performed. Oral vitamin D(3) (2000 IU daily) and elemental calcium (1.3 g daily) were prescribed for 90 days. The results are expressed as mean ± standard deviation (SD). Analysis of variance with a Fisher's post-hoc analysis was performed to test for differences between study visits. Subjects were classified as deficient (<20 ng/ml), relatively deficient (20-30 ng/ml), or not deficient (>30 ng/ml) in 25(OH)D.

RESULTS

Serum 25(OH)D levels were greater at months 1 and 3 than at baseline (26 ± 6 and 48 ± 17 vs. 14 ± 2 ng/ml; P = 0.005). Six of seven subjects were no longer deficient [25(OH)D >30 ng/ml] by month 3. Serum iPTH levels were significantly decreased at month 1 and month 3; serum NTx levels were significantly lower at month 3 than at baseline. Serum and urinary calcium levels remained within the normal range.

CONCLUSION

A daily prescription of 2000 IU of oral vitamin D(3) for 3 months safely raised serum 25(OH)D levels into the normal range in persons with chronic SCI on calcium supplementation.

Vitamin d and susceptibility of chronic lung diseases: role of epigenetics

Vitamin D deficiency is linked to accelerated decline in lung function, increased inflammation, and reduced immunity in chronic lung diseases. Epidemiological studies have suggested that vitamin D insufficiency is associated with low lung function in susceptible subjects who are exposed to higher levels of environmental agents (airborne particulates). Recent studies have highlighted the role of vitamin D and vitamin D receptor (VDR) in regulation of several genes that are involved in inflammation, immunity, cellular proliferation, differentiation, and apoptosis. Vitamin D has also been implicated in reversal of steroid resistance and airway remodeling, which are the hallmarks of chronic obstructive pulmonary disease (COPD) and severe asthma. VDR protein level is decreased in lungs of patients with COPD. VDR deficient mice develop an abnormal lung phenotype with characteristics of COPD, such as airspace enlargement and decline in lung function associated with increased lung inflammatory cellular influx, and immune-lymphoid aggregates formation. Dietary vitamin D may regulate epigenetic events, in particular on genes which are responsible for COPD susceptibility. Active metabolite of vitamin D, 1,25-dihydroxyvitamin D₃ plays an essential role in cellular metabolism and differentiation via its nuclear receptor (VDR) that cooperates with several other chromatin modification enzymes (histone acetyltransferases and histone deacetylases), thereby mediating complex epigenetic events in vitamin D signaling and metabolism. This review provides an update on the current knowledge and understanding on vitamin D, and susceptibility of chronic lung diseases in relation to the possible role of epigenetics in its molecular action. Understanding the molecular epigenetic mechanism of vitamin D/VDR would provide rationale for dietary vitamin D-mediated intervention in prevention and management of chronic lung diseases linked with vitamin D deficiency.

The challenges of UV-induced immunomodulation for children's health

Exposure to solar ultraviolet radiation (UVR) is recognised to have both beneficial and harmful effects on human health. With regard to immune responses, it can lead to suppression of immunity and to the synthesis of vitamin D, a hormone that can alter both innate and adaptive immunity. The consequences in children of such UV-induced changes are considerable: first there are positive outcomes including protection against some photoallergic (for example polymorphic light eruption) and T cell-mediated autoimmune diseases (for example multiple sclerosis) and asthma, and secondly there are negative outcomes including an increased risk of skin cancer (squamous cell carcinoma, basal cell carcinoma and cutaneous malignant melanoma) and less effective control of several infectious diseases. Many uncertainties remain regarding the amount of sun exposure that would provide children with the most effective responses against the variety of immunological challenges that they are likely to experience.

Vitamin D in autoimmune, infectious and allergic diseases: a vital player?

Vitamin D is a steroid hormone that is acquired via diet or synthesized in the skin upon UV exposure and needs subsequent hydroxylation steps to become activated as 1,25-dihydroxyvitamin D. While widely known for its role in maintaining bone health, vitamin D receptors have also been identified in different immune cell types. Many immune cells can also convert vitamin D into its bioactive form, thus enhancing the locally available concentrations to those required for the immunomodulatory effects of vitamin D. In this review, we summarize the genetic and epidemiologic data potentially linking vitamin D to autoimmune, infectious and allergic diseases. We also discuss how vitamin D influences the immune responses in each of those conditions based on the data generated using patient samples or preclinical models of each of these diseases.

Vitamin D status has a linear association with seasonal infections and lung function in British adults

Higher vitamin D concentrations have been proposed as a protective 'seasonal stimulus' against influenza, and there are suggestions for associations with other aspects of respiratory health. The aim of the present study was to investigate the relationship of current vitamin D status (measured by 25-hydroxyvitamin D, 25(OH)D) with respiratory infections and lung function. We used cross-sectional data from 6789 participants in the nationwide 1958 British birth cohort who had measurements of 25(OH)D, lung function (forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC)) and respiratory infections available from the age of 45 years. In this population, the prevalence of respiratory infections had a strong seasonal pattern in the opposite direction to the pattern for 25(OH)D concentrations. Each 10 nmol/l increase in 25(OH)D was associated with a 7 % lower risk of infection (95 % CI 3, 11 %) after adjustment for adiposity, lifestyle and socio-economic factors. For FEV1 and FVC, each 10 nmol/l increase in 25(OH)D was associated with 8 (95 % CI 3, 13) ml and 13 (95 % CI 7, 20) ml higher volume, respectively, after controlling for covariates. Associations of 25(OH)D with FEV1 and FVC were only slightly attenuated after further adjustment for infection and other respiratory illness. In conclusion, vitamin D status had a linear relationship with respiratory infections and lung function. Randomised controlled trials are warranted to investigate the role of vitamin D supplementation on respiratory health and to establish the underlying mechanisms.

Vitamin D and asthma

PURPOSE OF REVIEW

asthma is a disease that continues to carry a significant health burden on humanity. Vitamin D is thought to play a role in many chronic diseases as it may possess immunomodulatory properties. This article will review the role of vitamin D regulation on the immune system and its potential implication in the pathophysiology of asthma.

RECENT FINDINGS

vitamin D receptors are present on many cells in the body, specifically peripheral blood mononuclear cells. Vitamin D has been shown to regulate the balance of several pro-inflammatory and anti-inflammatory responses in the immune system. Studies have suggested that prenatal vitamin D intake has an effect on childhood wheezing and asthma. Additionally, vitamin D may play a role in asthma exacerbations, and recent evidence also suggests its importance in steroid resistant asthma.

SUMMARY

vitamin D has a complex role on the immune system and its regulation of various aspects of immunity has allowed speculation on its potential role in asthma. However, the net effect of vitamin D on the immune system and its role in asthma still remains unanswered. More research needs to address the diagnostic and therapeutic implications vitamin D may have in the future of asthma management.

Vitamin D: drug of the future. A new therapeutic approach

Besides increasing calcium absorption in the bowel and promoting the normal formation and mineralization of bone, vitamin D exerts relevant pleiotropic effects in different tissues. Serum levels of vitamin D show correlation with the risk of infections, cardiovascular diseases, cancer and autoimmune disorders. The possible therapeutic role of vitamin D in different kind of diseases: inflammatory, immunologic, infectious and neoplastic ones, explains the growing interest in this vitamin due to its pleiotropic effects, and makes it a candidate to become a potential drug in the next future.

Serum 25-hydroxy-vitamin D and ionised calcium in relation to lung function and allergen skin tests

BACKGROUND

Evidence suggests that higher levels of vitamin D and calcium are associated with greater lung function and that vitamin D is inversely associated with atopic sensitisation. It is unknown whether the associations of vitamin D and calcium with lung function are independent of each other or mediated by atopic sensitisation.

OBJECTIVE

To study the associations of 25-hydroxyvitamin D (25(OH)D) and ionised calcium levels with lung function and specific allergen sensitisation in adolescents (12-19 years) and adults (20-59 years) and to assess whether the associations with lung function are due to altered atopic sensitisation.

METHODS

This is a cross-sectional analysis of the data from the third National Health and Nutrition Examination Survey.

RESULTS

The 25(OH)D levels were positively associated with forced vital capacity in adolescents (0.035 (95% confidence interval (CI): 0.007-0.064) s.d.; s.d. in model adjusted for multiple confounders). This association and the previously reported association between higher serum levels of 25(OH)D and better lung function in adults were independent of serum calcium levels, which were not associated with lung function. In adults, calcium was associated with sensitisation to grass allergens (odds ratio per s.d., 1.17 (95% CI: 1.03-1.32), 1.15 (95% CI: 1.01-1.31) and 1.18 (95% CI: 1.06-1.32) for white oak, Bermuda grass and short ragweed, respectively) and peanut odds ratio 1.21 (95% CI: 1.02-1.43) after adjusting for age, gender and race/ethnicity, but these associations attenuated towards the null after adjusting for additional confounders. The associations were independent of 25(OH)D levels, which were not associated with allergen sensitisation.

CONCLUSIONS

Circulating levels of 25(OH)D are positively associated with lung function and this does not seem to be driven by allergen sensitisation or influenced by calcium levels.

The human health effects of ozone depletion and interactions with climate change

Depletion of the stratospheric ozone layer has led to increased solar UV-B radiation (280-315 nm) at the surface of the Earth. This change is likely to have had an impact on human exposure to UV-B radiation with consequential detrimental and beneficial effects on health, although behavioural changes in society over the past 60 years or so with regard to sun exposure are of considerable importance. The present report concentrates on information published since our previous report in 2007. The adverse effects of UV radiation are primarily on the eye and the skin. While solar UV radiation is a recognised risk factor for some types of cataract and for pterygium, the evidence is less strong, although increasing, for ocular melanoma, and is equivocal at present for age-related macular degeneration. For the skin, the most common harmful outcome is skin cancer, including melanoma and the non-melanoma skin cancers, basal cell carcinoma and squamous cell carcinoma. The incidence of all three of these tumours has risen significantly over the past five decades, particularly in people with fair skin, and is projected to continue to increase, thus posing a significant world-wide health burden. Overexposure to the sun is the major identified environmental risk factor in skin cancer, in association with various genetic risk factors and immune effects. Suppression of some aspects of immunity follows exposure to UV radiation and the consequences of this modulation for the immune control of infectious diseases, for vaccination and for tumours, are additional concerns. In a common sun allergy (polymorphic light eruption), there is an imbalance in the immune response to UV radiation, resulting in a sun-evoked rash. The major health benefit of exposure to solar UV-B radiation is the production of vitamin D. Vitamin D plays a crucial role in bone metabolism and is also implicated in protection against a wide range of diseases. Although there is some evidence supporting protective effects for a range of internal cancers, this is not yet conclusive, but strongest for colorectal cancer, at present. A role for vitamin D in protection against several autoimmune diseases has been studied, with the most convincing results to date for multiple sclerosis. Vitamin D is starting to be assessed for its protective properties against several infectious and coronary diseases. Current methods for protecting the eye and the skin from the adverse effects of solar UV radiation are evaluated, including seeking shade, wearing protective clothing and sunglasses, and using sunscreens. Newer possibilities are considered such as creams that repair UV-induced DNA damage, and substances applied topically to the skin or eaten in the diet that protect against some of the detrimental effects of sun exposure. It is difficult to provide easily understandable public health messages regarding "safe" sun exposure, so that the positive effects of vitamin D production are balanced against the negative effects of excessive exposure. The international response to ozone depletion has included the development and deployment of replacement technologies and chemicals. To date, limited evidence suggests that substitutes for the ozone-depleting substances do not have significant effects on human health. In addition to stratospheric ozone depletion, climate change is predicted to affect human health, and potential interactions between these two parameters are considered. These include altering the risk of developing skin tumours, infectious diseases and various skin diseases, in addition to altering the efficiency by which pathogenic microorganisms are inactivated in the environment.

A systematic review of the role of vitamin insufficiencies and supplementation in COPD

BACKGROUND

Pulmonary inflammation, oxidants-antioxidants imbalance, as well as innate and adaptive immunity have been proposed as playing a key role in the development of COPD. The role of vitamins, as assessed either by food frequency questionnaires or measured in serum levels, have been reported to improve pulmonary function, reduce exacerbations and improve symptoms. Vitamin supplements have therefore been proposed to be a potentially useful additive to COPD therapy.

METHODS

A systematic literature review was performed on the association of vitamins and COPD. The role of vitamin supplements in COPD was then evaluated.

CONCLUSIONS

The results of this review showed that various vitamins (vitamin C, D, E, A, beta and alpha carotene) are associated with improvement in features of COPD such as symptoms, exacerbations and pulmonary function. High vitamin intake would probably reduce the annual decline of FEV1. There were no studies that showed benefit from vitamin supplementation in improved symptoms, decreased hospitalization or pulmonary function.