Vitamin D and immune function: understanding common pathways

Dietary Interventions for Cancer Prevention: An Update to ACS International Guidelines

Cancer, the second leading cause of death worldwide, demands the identification of modifiable risk factors to optimize its prevention. Diet has emerged as a pivotal focus in current research efforts. This literature review aims to enhance the ACS guidelines on diet and cancer by integrating the latest findings and addressing unresolved questions. The methodology involved an advanced PubMed search with specific filters relevant to the research topic. Topics covered include time-restricted diet, diet quality, acid load, counseling, exercise and diet combination, Mediterranean diet, vegetarian and pescetarian diets, weight loss, dairy consumption, coffee and tea, iron, carbohydrates, meat, fruits and vegetables, heavy metals, micronutrients, and phytoestrogens. The review highlights the benefits of the Mediterranean diet in reducing cancer risk. Adherence to overnight fasting or carbohydrate consumption may contribute to cancer prevention, but excessive fasting may harm patients' quality of life. A vegetarian/pescetarian diet is associated with lower risks of general and colorectal cancer compared to a carnivorous diet. High heme and total iron intake are linked to increased lung cancer risk, while phytoestrogen intake is associated with reduced risk. Coffee and tea have a neutral impact on cancer risk. Finally, the roles of several preventive micronutrients and carcinogenic heavy metals are discussed.

Nonlinear correlation and mediation effects between serum 25-hydroxyvitamin D levels and all-cause mortality in COPD patients

Background

Numerous studies have shown that low levels of vitamin D are linked to a higher risk of inflammatory diseases and their progression. However, how vitamin D levels affect mortality in chronic obstructive pulmonary disease (COPD) patients is still unclear. Thus, this study aimed to explore the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels and the risk of death from all causes in U.S. adults with COPD.

Methods

This study analyzed 1,876 adults with COPD from the National Health and Nutrition Examination Survey (2005-2018). Mortality data up to December 31, 2019, were obtained from the National Death Index (NDI) records. Participants were categorized into three groups according to their 25(OH)D levels: Q1 (<50.0 nmol/L) for deficiency; Q2 (50.0-74.9 nmol/L) for insufficiency; and Q3 (≥75.0 nmol/L) for adequacy. A weighted Cox regression model assessed the link between 25(OH)D levels and mortality. Kaplan-Meier survival curves, subgroup, and sensitivity analyses were conducted. Additionally, the relationship between 25(OH)D and the hazard ratio (HR) was detailed through restricted cubic spline analysis. Mediation analysis revealed how 25(OH)D mediates the relationship between Dietary Inflammatory Index and mortality.

Results

There were 395 all-cause deaths during the follow-up, resulting in a mortality rate of 21.06%. After adjusting for potential confounders, higher 25(OH)D levels significantly correlated with a lower risk of all-cause mortality in COPD patients (HR = 0.52, 95% CI: 0.37-0.72, p < 0.001). Restricted cubic spline analysis indicated a non-linear relationship between 25(OH)D levels and all-cause mortality (p for nonlinear = 0.023), with levels below 63.4 nmol/L posing an independent risk for all-cause mortality in COPD patients (HR = 0.98, 95% CI: 0.97-0.99, p = 0.005). Sensitivity and subgroup analyses confirmed our results' robustness, with mediation analysis showing 25(OH)D's 22% mediating effect on diet-induced inflammation and all-cause mortality in COPD patients.

Conclusion

25(OH)D independently lowers the risk of all-cause mortality in COPD patients, with a non-linear L-shaped correlation, and mediates the effect of Dietary Inflammatory Index on mortality, suggesting new therapeutic possibilities.

Lower Vitamin D Level as a Risk Factor for Late Onset Neonatal Sepsis: An Observational Case-Control Study

OBJECTIVE

The aim of the study is to investigate the relation of neonatal and maternal vitamin D and late-onset sepsis (LOS).

STUDY DESIGN

One-hundred twenty term neonates along with their mothers were enrolled in this case-control study. Sixty neonates who were admitted in the neonatal intensive care unit by LOS and had not been previously admitted for last 48 hours and did not receive antibiotics or vitamin D were enrolled as cases (sepsis) group. On the other hand, 60 healthy term neonates were referred as control group. Maternal and neonatal serum 25-OH vitamin D levels were assessed in both the cohorts.

RESULTS

Maternal and neonatal 25-OH vitamin D levels in cases (17.2 and 16.1 ng/mL, respectively) were significantly lower than in controls (22.7 and 21 ng/mL, respectively) p = 0.001. In the study group, the neonatal 25-OH vitamin D was negatively correlated with C-reactive protein and length of hospital stay (r = -0.616 and -0.596, respectively) p <0.001 for both. With a cut-off value of 12.9 ng/mL, the specificity and positive predictive value of neonatal vitamin D were 83.3 and 74.4%, respectively. The odds ratio was 1.088 (95% CI = 1.034-1.144)) for LOS in vitamin D-deficient neonates.

CONCLUSION

Neonates with higher vitamin D level are at lower risk of LOS than those with vitamin D deficiency. Maternal vitamin D correlates with neonatal vitamin D. These data suggest that maternal vitamin supplementation during pregnancy may lower the risk of LOS.

KEY POINTS

· Neonatal and maternal vitamin D deficiency increase risk of LOS.. · Neonatal vitamin D correlates with maternal vitamin D.. · Neonatal vitamin D is independent predictor for LOS..

Dietary inflammatory index is associated with Vitamin D in CKD patients

OBJECTIVES

Multiple observational studies have shown that low serum level of 25-hydroxyvitamin D (25(OH)D) in patients with chronic kidney disease (CKD) have been associated with a faster progression of kidney disease and a higher risk of all-cause mortality. We aim to assess the association between dietary inflammatory index (DII) with Vitamin D in adults with CKD.

METHOD

The National Health and Nutrition Examination Survey appropriated participants from 2009 to 2018 were enrolled. The patients who were under the age of 18, pregnant, and having incomplete data were excluded. DII score were calculated based on a single 24-h dietary recall interview for each participant. Mutivariable regression analysis and subgroup analysis were utilized to determine the independent associations between vitamin D with DII in CKD patients.

RESULTS

In total, 4283 individuals were finally included. The results showed a negative association between DII scores and 25(OH)D with statistical significance (β =  - 1.83, 95% CI  - 2.31,  - 1.34, P < 0.001). In subgroup analysis stratified by gender, low eGFR, age and diabetes, the negative association between DII scores and 25(OH)D was still significant (all P for trend < 0.05). The results from interacion test indicated that the magnitude of the association was the same for the population with and without low eGFR (P for interacion = 0.464).

CONCLUSION

Higher consumption of pro-inflammatory diet correlates negatively with the 25(OH)D level in CKD patients with and without low eGFR. Anti-inflammatory diet management may reduce the reduction of vitamin D in CKD patients.

Vitamin D Status Modestly Regulates NOD-Like Receptor Family with a Pyrin Domain 3 Inflammasome and Interleukin Profiles among Arab Adults

Vitamin D (VD) deficiency has been associated with inflammation and dysregulation of the immune system. The NLRP3 inflammasome, a critical immune response component, plays a pivotal role in developing inflammatory diseases. VD hinders NLRP3 inflammasome activation and thus exerts anti-inflammatory effects. This study aimed to analyze the effect of VD deficiency on circulating levels of NLRP3 inflammasomes (NLRP3 and caspase-1) and associated interleukins (IL-1α, IL-1β, IL-18, IL-33 and IL-37) in Saudi adults. Methods: A total of 338 Saudi adults (128 males and 210 females) (mean age = 41.2 ± 9.1 years and mean BMI 31.2 ± 6.5 kg/m2) were included. Overnight-fasting serum samples were collected. Participants were stratified according to their VD status. Serum levels of NLRP3 inflammasomes and interleukins of interest were assessed using commercially available immuno-assays. Individuals with VD deficiency had significantly lower mean 25(OH)D levels than those with a normal VD status (29.3 nmol/L vs. 74.2 nmol/L, p < 0.001). The NLRP3 levels were higher in the VD-deficient group than their VD-sufficient counterparts (0.18 vs. 0.16, p = 0.01). Significant inverse associations were observed between NLRP3 levels with age (r = -0.20, p = 0.003) and BMI (r = -0.17, p = 0.01). Stepwise regression analysis identified insulin (β = 0.38, p = 0.005) and NLRP3 (β = -1.33, p = 0.03) as significant predictors of VD status, explaining 18.3% of the variance. The findings suggest that the VD status modestly regulates NLRP3 inflammasome and interleukin activities. This may provide novel insights into the pathogenesis and management of inflammatory disorders.

Age-related changes in vitamin D metabolism and vitamin D receptor expression in equine alveolar macrophages: a preliminary study

The vitamin D receptor (VDR)-vitamin D axis modulates pulmonary immunity in people but its role in equine immunity is unknown. Bacterial pneumonia causes high morbidity/mortality in foals and alveolar macrophages (AMφ) are important for pulmonary defenses. Age-related variations in vitamin D-mediated function of AMφ might contribute to the foal's susceptibility to pneumonia. Our aim was to assess the impact of age on equine vitamin D metabolism and VDR expression in AMφ. AMφ and plasma was collected from healthy foals (2, 4 and 8 weeks old) and adult horses (once). AMφ VDR expression was determined via RT-qPCR and plasma vitamin D metabolites quantified via immunoassays. Data were analyzed with linear mixed models. Inactive-vitamin D metabolite concentrations were lowest in foals at 2 weeks and lower at 2 and 4 weeks compared to adults (P < 0.001). Active-vitamin D metabolite concentrations were higher in foals than adults (P < 0.05). VDR expression was detected in AMφ in all animals and was highest in 2-week-old foals. Vitamin D metabolism and AMφ VDR expression are impacted by age in horses. This may have immunological consequences in foals given the key role that the VDR-vitamin D axis has in pulmonary immunity in other species.

Association of CYP24A1 Gene rs6127099 (A > T) Polymorphism with Lower Risk to COVID-19 Infection in Kazakhstan

In December 2019, SARS-CoV-2 was identified in Wuhan, China. Infection by SARS-CoV-2 causes coronavirus disease 2019 (COVID-19), which is characterized by fever, cough, dyspnea, anosmia, and myalgia in many cases. There are discussions about the association of vitamin D levels with COVID-19 severity. However, views are conflicting. The aim of the study was to examine associations of vitamin D metabolism pathway gene polymorphisms with symptomless COVID-19 susceptibility in Kazakhstan. The case-control study examined the association between asymptomatic COVID-19 and vitamin D metabolism pathway gene polymorphisms in 185 participants, who previously reported not having COVID-19, were PCR negative at the moment of data collection, and were not vaccinated. A dominant mutation in rs6127099 (CYP24A1) was found to be protective of asymptomatic COVID-19. Additionally, the G allele of rs731236 TaqI (VDR), dominant mutation in rs10877012 (CYP27B1), recessive rs1544410 BsmI (VDR), and rs7041 (GC) are worth consideration since they were statistically significant in bivariate analysis, although their independent effect was not found in the adjusted multivariate logistic regression model.

Reducing Virus Infection Risk in Space Environments through Nutrient Supplementation

Space exploration has brought many challenges to human physiology. In order to evaluate and reduce possible pathological reactions triggered by space environments, we conducted bioinformatics analyses on the methylation data of the Mars 520 mission and human transcriptome data in the experiment simulating gravity changes. The results suggest that gene expression levels and DNA methylation levels were changed under the conditions of isolation and gravity changes, and multiple viral infection-related pathways were found in the enrichment analysis results of changed genes including Epstein Barr virus (EBV) infection, Hepatitis B virus (HBV) infection, Herpes simplex virus (HSV) infection and Kaposi's sarcoma-associated herpesvirus (KHSV) infection. In this study, we found that Epigallocatechin-3-gallate (EGCG) and vitamin D are helpful in reducing viral infection risk. In addition, the causal associations between nutrients and viral infections were calculated using Two sample Mendelian Randomization (2SMR) method, the results indicated that vitamin D can reduce EBV infection and HBV infection risk. In summary, our study suggests that space environments increase the risk of human viral infection, which may be reduced by supplementing EGCG and vitamin D. These results can be used to formulate medical plans for astronauts, which have practical application value for future space exploration.

Oral Health in Breast Cancer Women with Vitamin D Deficiency: A Machine Learning Study

Breast cancer (BC) survivors treated with aromatase inhibitors (AIs) commonly show several pathological issues, including poor oral health, bone health impairment, and vitamin D deficiency. However, to date, oral health issues in BC survivors treated with AIs have been poorly investigated and their relationship with vitamin D deficiency are far from being understood. This study aimed to evaluate the correlation between oral health and vitamin D status in BC survivors undergoing treatment with AIs through a machine learning approach. In this cross-sectional study, we included post-menopausal BC women with vitamin D deficiency undergoing AIs therapy. The outcome measures were the following: oral health indexes as the Decayed, Missing, and Filled Permanent Teeth Index (DMFT); serum levels of 25(OH)D₃; Bone Mineral Density (BMD); and the diagnosis of osteoporosis. We included 41 post-menopausal BC women, mean aged 66.10 ± 8.47 years, with mean serum levels of vitamin D of 14.63 ± 6.62 ng/mL. Furthermore, 56.10% of patients had a diagnosis of osteoporosis and 36.59% were osteopenic. DMFT was significantly related to smoking (p-value = 0.005) and dental floss use (p-value = 0.001). There was a significant correlation between DMFT and vitamin D levels (Pearson’s r: −0.73; p-value = 0.001). The regression machine learning model showed that vitamin D status and the use of dental floss were the most relevant variables in terms of correlation with DMFT. In conclusion, vitamin D deficiency, inadequate use of dental floss, and smoking had a negative impact on oral health in BC women. Thus, vitamin D deficiency screening and supplementation and a prompt oral rehabilitation plan should be suggested and implemented in the complex treatment framework of BC survivors undergoing treatment with AIs.

[Serum 25-hydroxyvitamin D expression and its correlation in patients with vestibular neuritis]

Objective:To investigate the expression level of serum 25-（OH） D and its correlation in patients with vestibular neuritis（VN）. Methods:30 acute VN patients and 50 age-and sex-matched healthy controls who attended the Otolaryngology, Head and Neck Surgery Department of the First Hospital of Shanxi Medical University from October 2020 to October 2021 were selected. The demographic and clinical data of all subjects were recorded, the levels of serum 25-（OH） D and inflammatory markers were measured and compared, and the changes of serum 25-（OH） D levels in convalescent patients with VN were followed up. Results:The serum level of 25-（OH） D in the acute phase VN group was significantly lower than that in healthy controls[（10.14±2.92） ng/mL vs （20.61±4.70） ng/mL, P<0.01], and the deficiency rate of 100.0%（30/30） was significantly higher than 54.0%（27/50）. Moreover, the serum level of 25-（OH） D in the recovery period（3 months later） was significantly higher[（10.14±2.92） ng/mL vs （15.94±4.88） ng/mL, P<0.01], and the deficiency rate was significantly decreased by 76.7%（23/30）. However, the serum 25-（OH） D level was significantly lower in both the VN group than that in both the acute period and the recovery group, and the deficiency rate was significantly higher than that in the control group. Multivariate binary Logistic regression model analysis showed that low-level serum 25-（OH） D was associated with the onset of VN, with an OR value of 0.193（95%CI=0.043-0.861, P=0.031）. In addition, the results of this study showed that peripheral blood leukocyte（WBC） and neutrophil / lymphocyte ratio（NLR） levels in the acute VN group were significantly higher than in healthy controls[（7.65±3.02） ×10⁸/L vs （5.50±2.50） ×10⁸/L, P<0.01; （2.46±2.95） ×100% vs（1.67±0.92） ×100%, P<0.01 ], and there was no significant difference in Platelet / lymphocyte ratio（PLR） and and average platelet volume（MPV） levels in the two groups（P>0.05）. There were no significant differences in age distribution, sex ratio, body mass index, persistent health problems, or lifestyle groups（P>0.05）. Conclusion:This study is the first to detect serum 25-（OH） D level and inflammation index level, and dynamically assess the serum 25-（OH） D level in different stages, found that low serum 25-（OH） D is associated with the onset of VN, physiological concentration of serum 25-（OH） D is a protective factor of VN, vitamin D supplementation therapy may be a new target of VN treatment.

The association between dairy products and the risk of COVID-19

BACKGROUND

The fast spread of the coronavirus disease 2019 (COVID-19) epidemic and its high mortality were quickly noticed by the health community. Dairy products have been recognized as part of a healthy diet that helps strengthen body immunity and prevent infections. The present study can provide a comprehensive picture of the associations between dairy products consumption and COVID-19 incidence.

METHODS

This study was undertaken on 8801 adults participants of Yazd Health Study (YaHS) and Taghzieh Mardom-e-Yazd (TAMIZ) study aged 20 to 70 years. Data on dietary intakes were obtained using a validated food frequency questionnaire (FFQ). Multivariable logistic regression analysis was used to assess the association between dairy consumption and COVID-19.

RESULT

Our finding indicated that moderate intake of total dairy (OR: 0.63, 95% CI 0.46-0.87, P-trend = 0.97) could reduce the odds of COVID-19 and higher intake of low-fat dairy products (OR: 0.51 CI: 0.37-0.69, p-trend < 0.001) and low-fat milk (OR: 0.47 CI: 0.35-0.64, p-trend < 0.001) had a protective effect on COVID-19 after adjusting for confounders. However, higher intake of high-fat-dairy-product (OR: 1.40 CI: 1.09-1.92, p-trend = 0.03), high-fat milk (OR: 1.54 CI: 1.20-1.97, p-trend < 0.001), total yogurt (OR: 1.40 CI: 1.04-1.89, p-trend = 0.01), cheese (OR: 1.80 CI: 1.27-2.56, p-trend = 0.001), and butter (OR: 1.80 CI: 1.04-3.11, p-trend = 0.02) were related to increase the odds of COVID-19.

CONCLUSIONS

Moderate intake of total dairy could reduce odds of COVID-19 by 37% and, a higher intake of low-fat dairy products had a protective role on COVID-19. Although our study has promising results, stronger clinical studies are needed.

Efficacy of Vitamin D Supplements in Treatment of Acute Respiratory Infection: A Meta-Analysis for Randomized Controlled Trials

BACKGROUND

Recent randomized controlled trials (RCTs) have reported inconsistent findings regarding the efficacy of vitamin D supplementation in the treatment of acute respiratory infections (ARIs). This study aimed to investigate the efficacy of vitamin D supplementation in the treatment of ARIs using a meta-analysis of RCTs.

METHODS

PubMed, EMBASE, and the Cochrane Library were searched for relevant articles in June 2021. Two of the authors independently assessed the eligibility of the trials.

RESULTS

Out of 390 articles retrieved from the databases, we included 18 RCTs, which involved 3648 participants, with 1838 in an intervention group and 1810 in a control group in the final analysis. In the meta-analysis of all the trials, vitamin D supplements had a beneficial effect in the treatment of ARIs (relative risk (RR) = 1.07; 95% confidence interval (CI), 1.01-1.13; I² = 66.9%). Publication bias was observed in the funnel plot. In the subgroup meta-analysis of high-quality RCTs, no significant efficacy of vitamin D supplements was found (RR = 1.02; 95% CI, 0.98-1.06; I² = 24.0%). Although statistically significant changes of 7% in the treatment effects were observed, they are not considered as clinically substantial ones.

CONCLUSIONS

The current meta-analysis suggests that vitamin D supplements are not clinically effective in the treatment of ARIs.

Vitamin D attenuates COVID-19 complications via modulation of proinflammatory cytokines, antiviral proteins, and autophagy

INTRODUCTION

Global emergence of coronavirus disease-19 (COVID-19) has clearly shown variable severity, mortality, and frequency between and within populations worldwide. These striking differences have made many biological variables attractive for future investigations. One of these variables, vitamin D, has been implicated in COVID-19 with rapidly growing scientific evidence.

AREAS COVERED

The review intended to systematically explore the sources, and immunomodulatory role of vitamin D in COVID-19. Search engines and data sources including Google Scholar, PubMed, NCBI, Scopus, and Web of Science were used for data collection. The search terms used were Vitamin D, COVID-19, immune system, and antiviral mechanism. Overall, 232 sources of information were collected and 188 were included in this review.

EXPERT OPINION

Interaction of vitamin D and vitamin D receptor (VDR) triggers the cellular events to modulate the immune system by regulation of many genes. Vitamin D operates as a double-edged sword against COVID-19. First, in macrophages, it promotes the production of antimicrobial and antiviral proteins like β-defensin 2 and cathelicidin, and these proteins inhibit the replication of viral particles and promote the clearance of virus from the cells by autophagy. Second, it suppresses cytokine storm and inflammatory processes in COVID-19.

Exploring the Immune-Boosting Functions of Vitamins and Minerals as Nutritional Food Bioactive Compounds: A Comprehensive Review

Food components have long been recognized to play a fundamental role in the growth and development of the human body, conferring protective functionalities against foreign matter that can be severe public health problems. Micronutrients such as vitamins and minerals are essential to the human body, and individuals must meet their daily requirements through dietary sources. Micronutrients act as immunomodulators and protect the host immune response, thus preventing immune evasion by pathogenic organisms. Several experimental investigations have been undertaken to appraise the immunomodulatory functions of vitamins and minerals. Based on these experimental findings, this review describes the immune-boosting functionalities of micronutrients and the mechanisms of action through which these functions are mediated. Deficiencies of vitamins and minerals in plasma concentrations can lead to a reduction in the performance of the immune system functioning, representing a key contributor to unfavorable immunological states. This review provides a descriptive overview of the characteristics of the immune system and the utilization of micronutrients (vitamins and minerals) in preventative strategies designed to reduce morbidity and mortality among patients suffering from immune invasions or autoimmune disorders.

Vitamin D3 Treatment Alters Thyroid Functional Morphology in Orchidectomized Rat Model of Osteoporosis

Vitamin D plays an essential role in prevention and treatment of osteoporosis. Thyroid hormones, in addition to vitamin D, significantly contribute to regulation of bone remodeling cycle and health. There is currently no data about a possible connection between vitamin D treatment and the thyroid in the context of osteoporosis. Middle-aged Wistar rats were divided into: sham operated (SO), orchidectomized (Orx), and cholecalciferol-treated orchidectomized (Orx + Vit. D₃; 5 µg/kg b.m./day during three weeks) groups (n = 6/group). Concentration of 25(OH)D in serum of the Orx + Vit. D₃ group increased 4 and 3.2 times (p < 0.0001) respectively, compared to Orx and SO group. T_4, TSH, and calcitonin in serum remained unaltered. Vit. D₃ treatment induced changes in thyroid functional morphology that indicate increased utilization of stored colloid and release of thyroid hormones in comparison with hormone synthesis, to maintain hormonal balance. Increased expression of nuclear VDR (p < 0.05) points to direct, TSH independent action of Vit. D on thyrocytes. Strong CYP24A1 immunostaining in C cells suggests its prominent expression in response to Vit. D in this cell subpopulation in orchidectomized rat model of osteoporosis. The indirect effect of Vit. D on bone, through fine regulation of thyroid function, is small.

Dietary 25(OH)D3 supplementation to gestating and lactating sows and their progeny affects growth performance, carcass characteristics, blood profiles and myogenic regulatory factor- related gene expression in wean-finish pigs

Objective

This experiment investigated the effects of supplementing vitamin D₃-fortified sow and progeny diets with 25(OH)D₃ on growth performance, carcass characteristics, immunity, and pork meat quality.

Methods

The present study involved the assessment of supplementing the diet of sows and their progeny with or without 25 (OH)D₃ in a 2×2 factorial arrangement on the performance and production characteristics of wean-finish pigs. Forty-eight multiparous sows were assigned to a basal diet containing 2000 IU/kg vitamin D₃ and supplemented without (CON) or with (TRT) 50 μg/kg 25 (OH)D₃. At weaning, a total of 80 pigs each from CON and TRT sows were allocated to weaning and growing-finishing basal diets fortified with 2,500 and 1,750 IU/kg vitamin D₃ respectively and supplemented without or with 50 μg/kg 25(OH)D₃.

Results

Sows fed 25(OH)D₃-supplemented diets improved pre-weaning growth rate of nursing piglets. A significant sow and pig weaning diet effect was observed for growth rate and feed efficiency (p<0.05) during days 1 to 42 post-weaning. Pigs consuming 25(OH)D₃-supplemented diets gained weight faster (p = 0.016), ate more (p = 0.044) and tended to convert feed to gain more efficiently (p = 0.088) than those fed CON diet between days 98 and 140 post-weaning. Supplemental 25(OH)D₃ improved water holding capacity and reduced drip loss of pork meat, increased serum 25(OH)D₃ level, produced higher interleukin-1 and lower interleukin-6 concentrations in blood circulation, downregulated myostatin (MSTN) and upregulated myogenic differentiation (MYOD) and myogenic factor 5 (MYF5) gene expressions (p<0.05).

Conclusion

Supplementing vitamin D₃-fortified sow and wean-finish pig diets with 50 μg/kg 25(OH)D₃ significantly improved production performance suggesting their current dietary vitamin D₃ levels are insufficient. In fulfilling the total need for vitamin D, it is strongly recommended to add 50 μg/kg 25(OH)D₃ “on top” to practical vitamin D₃-fortified sow and wean-finish pig diets deployed under commercial conditions.

Role of vitamin D in regulating COVID-19 severity-An immunological perspective

Vitamin D, a key nutrient/prohormone classically associated with skeletal health, is also an important immunomodulator, with pleotropic effects on innate and adaptive immune cells. Outcomes of several chronic, autoimmune, and infectious diseases are linked to vitamin D. Emergent correlations of vitamin D insufficiency with coronavirus-induced disease 2019 (COVID-19) severity, alongside empirical and clinical evidence of immunoregulation by vitamin D in other pulmonary diseases, have prompted proposals of vitamin D supplementation to curb the COVID-19 public health toll. In this review paper, we engage an immunological lens to discuss potential mechanisms by which vitamin D signals might regulate respiratory disease severity in severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infections, vis a vis other pulmonary infections. It is proposed that vitamin D signals temper lung inflammatory cascades during SARS-CoV2 infection, and insufficiency of vitamin D causes increased inflammatory cytokine storm, thus leading to exacerbated respiratory disease. Additionally, analogous to studies of reduced cancer incidence, the dosage of vitamin D compounds administered to patients near the upper limit of safety may serve to maximize immune health benefits and mitigate inflammation and disease severity in SARS-CoV2 infections. We further deliberate on the importance of statistically powered clinical correlative and interventional studies, and the need for in-depth basic research into vitamin D-dependent host determinants of respiratory disease severity.

The Relationship Between Vitamin D and Infections Including COVID-19: Any Hopes?

Vitamin D is proposed to have a potential role in the pathogenicity, clinical presentation, prognosis, complications, and treatment of several diseases. In addition to its well-known role in calcium metabolism, vitamin D regulates both innate and adaptive immunity, and subsequently modulates the antiviral and antibacterial inflammatory immune responses. In view of the emerging coronavirus disease 2019 (COVID-19) pandemic, searching for potential therapeutic and protective strategies is of urgent interest, and vitamin D is one of the promising agents in this field. In this review, we present data from literature that supports the promising role of vitamin D in treatment and/or prevention of several infections including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This review summarizes vitamin D metabolism and its role in inflammation, thrombosis and immune regulation. It also reviews, in short, the role of vitamin D and the impact of its deficiency in several infections namely tuberculosis, influenza, human immunodeficiency virus (HIV), and SARS-CoV-2. Considering the roles of vitamin D on immune modulation, controlling of thrombosis, and attacking several microorganisms, the current review will elaborate on the association between these salient roles of vitamin D and the pathogenicity of various infectious agents including COVID-19. Consequently, the comprehensive finding of the current review shows a possible significant impact of vitamin D supplement as a hope in preventing, treating, and/or improving the progression of certain infections, specifically during the worldwide attempts to fight against the COVID-19 pandemic and minimize the severity of health complications encountered accordingly. In addition, avoiding a status of vitamin D deficiency to obtain its positive effects on the immune system and its protective mechanism during infections will be a general benefit overall.

Role of Vitamin D and Vitamin D Receptor in Oral Lichen Planus: A Systematic Review

Background

Oral lichen planus (OLP) is known to be a chronic inflammatory disease associated with various other systemic disorders. Studies have shown that vitamin D deficiency can be involved in the pathogenesis of lichen planus. The aim of this study was to investigate the role of vitamin D and vitamin D receptor in OLP.

Methods

In this review study, all English and Persian articles were searched by relevant keywords from the Google scholar, PubMed, science direct, Cochrane, Scopus and Sid databases until January 2020.

Results

From the 16 articles obtained after reviewing the abstracts, finally 14 appropriate articles were included in this study.

Conclusion

According to the results of the studies, vitamin D deficiency may be associated with an increased risk of OLP lesions.

Vitamin D and coronavirus disease 2019 (COVID-19): rapid evidence review

BACKGROUND

The rapid global spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), has re-ignited interest in the possible role of vitamin D in modulation of host responses to respiratory pathogens. Indeed, vitamin D supplementation has been proposed as a potential preventative or therapeutic strategy. Recommendations for any intervention, particularly in the context of a potentially fatal pandemic infection, should be strictly based on clinically informed appraisal of the evidence base. In this narrative review, we examine current evidence relating to vitamin D and COVID-19 and consider the most appropriate practical recommendations.

OBSERVATIONS

Although there are a growing number of studies investigating the links between vitamin D and COVID-19, they are mostly small and observational with high risk of bias, residual confounding, and reverse causality. Extrapolation of molecular actions of 1,25(OH)₂-vitamin D to an effect of increased 25(OH)-vitamin D as a result of vitamin D supplementation is generally unfounded, as is the automatic conclusion of causal mechanisms from observational studies linking low 25(OH)-vitamin D to incident disease. Efficacy is ideally demonstrated in the context of adequately powered randomised intervention studies, although such approaches may not always be feasible.

CONCLUSIONS

At present, evidence to support vitamin D supplementation for the prevention or treatment of COVID-19 is inconclusive. In the absence of any further compelling data, adherence to existing national guidance on vitamin D supplementation to prevent vitamin D deficiency, predicated principally on maintaining musculoskeletal health, appears appropriate.

Cytomegalovirus Infection Downregulates Vitamin D Receptor in Patients Undergoing Hematopoietic Stem Cell Transplantation

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative option for patients with hematologic diseases but is associated with high mortality and morbidity. Cytomegalovirus (CMV) infection is common in HSCT patients and modulates vitamin D metabolism in vitro. We aimed at validating CMV-associated vitamin D metabolism in vivo in HSCT.

METHODS

Patients treated for significant CMV viremia after HSCT were evaluated for CMV load before, during, and after antiviral treatment. RNA was isolated from whole-blood samples to test for regulation of key components of the vitamin D receptor (VDR) pathway during different phases of CMV viremia.

RESULTS

CMV viremia developed a mean time of 102 (±34) d post-HSCT. Maximum levels of CMV-DNA reached a mean of 5668 (±7257) copies/mL. VDR expression was downregulated to a mean of 64.3% (±42.5%) relative to the VDR expression pre-CMV viremia (P = 0.035) and lagged in recovery following antiviral treatment. Toll-like receptor (TLR) 2 mRNA was upregulated to 225.4% during CMV viremia relative to the expression pre-CMV viremia (P = 0.012) but not TLR6/7/8 and the TLR-adaptor protein MyD88. Levels of 25-OH vitamin D were reduced in all viremic patients (48.0 ± 4.8 versus 25.1 ± 3.7 ng/mL) and were even lower after periods of CMV viremia compared with the control group (48.3 ± 3.5 versus 17.8 ± 1.8 ng/mL; P = 0.008).

CONCLUSIONS

CMV viremia is associated with significant dysregulation of vitamin D metabolism in HSCT patients.

Interferon alpha serum level association with low vitamin D levels in Chinese patients with primary Sjögren’s syndrome

The purpose of this retrospective cross-sectional study was to explore the clinical and pathogenic significance of vitamin D and its relationship with interferon-α (IFN-α) in Chinese patients with primary Sjögren’s syndrome (pSS). In our study, 32 pSS patients and 50 healthy controls were included. Serum vitamin D and IFN-α concentrations were determined by enzyme-linked immunosorbent assay (ELISA) and analyzed with the correlations of EULAR Sjögren’s Syndrome Disease Activity Index (ESSDAI). The multiple linear regression analysis of 25-OH vitamin D3 level with ESSDAI scores in pSS patients was also investigated. Serum 25-OH vitamin D3 significantly correlated in an inverse manner with ESSDAI scores ( p < 0.001, r = −0.781) and IgG ( p < 0.001, r = −0.64). Serum 25-OH vitamin D3 were only related to peripheral nervous system (PNS) domain deficiency. Further, serum IFN-α was positively correlated with ESSDAI, but negatively correlated with serum 25-OH vitamin D3. These results suggest an important role of vitamin D regulating disease activity in pSS patients and value of supplement vitamin D in pSS treatment.

Micronutrients and bioactive substances: Their potential roles in combating COVID-19

OBJECTIVES

The coronavirus disease 2019 (COVID-19) pandemic is seriously threatening public health and setting off huge economic crises across the world. In the absence of specific drugs for COVID-19, there is an urgent need to look for alternative approaches. Therefore, the aim of this paper was to review the roles of micronutrients and bioactive substances as potential alternative approaches in combating COVID-19.

METHODS

This review was based on the literature identified using electronic searches in different databases.

RESULTS

Vitamins (A, B, C, D, and E), minerals (selenium and zinc), and bioactive substances from curcumin, echinacea, propolis, garlic, soybean, green tea, and other polyphenols were identified as having potential roles in interfering with spike glycoproteins, angiotensin converting enzyme 2, and transmembrane protease serine 2 at the entry site, and inhibiting activities of papain-like protease, 3 chymotrypsin-like protease, and RNA-dependent RNA polymerase in the replication cycle of severe acute respiratory syndrome coronavirus 2. Having immunomodulating, antiinflammatory, antioxidant, and antiviral properties, such micronutrients and bioactive substances are consequently promising alterative nutritional approaches to combat COVID-19.

CONCLUSIONS

The roles of micronutrients and bioactive substances in the fight against COVID-19 are exciting areas of research. This review may suggest directions for further study.

The association of vitamin D levels and insulin resistance

OBJECTIVE

Vitamin D deficiency and insulin resistance have great prevalence in society. The latest studies indicate an inverse association between Vitamin D levels, insulin resistance, and Type 2 diabetes. The objective of this study was to investigate the effect of vitamin D status on insulin resistance.

METHODS

In a cross-sectional study, 2160 participants were randomly recruited from a nutrition clinic in Tehran, Iran, 1057 (48.9%) were female and 1103 (51.1%) male. Information was gathered by a questionnaire. Following 12-h fasting, fasting plasma glucose (FPG) and insulin levels, as well as 25-hydroxy vitamin D levels were measured. 2-H glucose and insulin levels measured after consumption of 75 g glucose, HOMA2-IR, and HOMA-β indices were then calculated.

RESULTS

The average serum Vitamin D was 22.3 + 8.9 nmol/L and the prevalence of Vitamin D deficiency was 100%. There was an inverse relationship between Vitamin D levels and age, BMI, waist circumference, and all metabolic parameters (p < 0.001 in all) and a direct association with levels of exercise. Two logistic regression models were used to adjust for confounding variables; firstly, for age, gender, and smoking and secondly, additionally for BMI and energy intake. Both models showed a significant inverse relationship between Vitamin D levels and FPG and insulin levels, 2-h glucose and insulin levels, and HOMA2-IR. The optimum cut point for vitamin D was calculated at about 25 nmol/L for preventing insulin resistance.

CONCLUSION

This study illustrated that there is a statistically significant inverse relationship between Vitamin D levels and insulin resistance.

The Effect of Vitamin D Deficiency on Overgrowth of Uterine Fibroids: A Blinded Randomized Clinical Trial

Background

To evaluate the effects of vitamin D (vitD) supplement on uterine fibroid growth.

Materials and Methods

A randomized blinded clinical trial was conducted at a tertiary university-based hospital from August 2017 to September 2018. Totally, 204 women were enrolled into the study. They had at least one uterine fibroid >10 mm on transvaginal ultrasound and their vitD level was insufficient (i.e. 20-30 ng/ml). The intervention group was treated with vitD 50000 U supplements for two months. After 2 months, ultrasound screening and vitD level measurement was done in both groups.

Results

At first, the mean serum vitD levels in intervention and control group were 23.62 and 23.20 ng/ml, respec- tively. After 8 weeks, the mean serum vitD levels in the control and intervention group were 22.72 and 28.56 ng/ml respectively (P<0.05). Also, mean fibroma diameter in the intervention group before and after 8 weeks of vitD supple- mentation was 43 ± 4.68 and 42.6 ± 1.31 mm, respectively. Mean uterine fibroid diameter in the control group which did not receive vitD supplements, before and after 8 weeks was 41.98 ± 5.25 and 47.81 ± 3.42 mm, respectively. The variation in the mean size of the uterine fibroid between the control and intervention group which was respectively about 5.83 mm increase and 0.48 mm decrease, was significant (P<0.001).

Conclusion

Our results showed that vitD supplementation prevents fibroid growth. It seems that vitD supple- ment is a simple, safe and inexpensive modality for leiomyoma growth prevention (Registration number: IRCT201703122576N15).

Vitamin D status was associated with sepsis in critically ill children: A PRISMA compliant systematic review and meta-analysis

BACKGROUND

Sepsis leads to the high mortality in critically ill infants and children. It is still controversial whether vitamin D deficiency was associated with the incidence of sepsis. Thus we designed the systematic review and meta-analysis.

METHODS

The Ovid Medline, Embase, PubMed, and Cochrane library were systematically searched until April 5, 2020. The 25 hydroxyvitamin D (25-OHD) level was recorded and set 20 ng/mL as cut-off in cohort study to divide the lower and higher 25-OHD group. The odds ratio (OR) and 95% confidence intervals (CIs) were calculated for comparing the impact of vitamin D deficiency on the incidence of sepsis in critically ill children.

RESULTS

A total of 27 studies were included with 17 case-control studies and 10 cohort studies. In those case-control studies, the maternal 25-OHD level and neonatal 25-OHD level in sepsis group was significant lower than non-sepsis group (P < .001). The percentage of severe vitamin D deficiency was significant higher in sepsis group comparing to non-sepsis group (odds ratio [OR] = 2.66, 95% CI = 1.13-6.25, P < .001). In those cohort studies, the incidence of sepsis in lower 25-OHD group was 30.4% comparing with 18.2% in higher 25-OHD level group. However, no statistical significant difference in terms of mechanical ventilation rate and 30-day mortality.

CONCLUSION

We demonstrated that critically ill infants and children with sepsis could have a lower 25-OHD level and severe vitamin D deficiency comparing to those without sepsis. Future studies should focus on the association of vitamin D supplement and the occurrence of sepsis in critically ill children.

The transcriptomic profiling of SARS-CoV-2 compared to SARS, MERS, EBOV, and H1N1

The SARS-CoV-2 (COVID-19) pandemic is a global crisis that threatens our way of life. As of November 18, 2020, SARS-CoV-2 has claimed more than 1,342,709 lives, with a global mortality rate of ~2.4% and a recovery rate of ~69.6%. Understanding the interaction of cellular targets with the SARS-CoV-2 infection is crucial for therapeutic development. Therefore, the aim of this study was to perform a comparative analysis of transcriptomic signatures of infection of SARS-CoV-2 compared to other respiratory viruses (EBOV, H1N1, MERS-CoV, and SARS-CoV), to determine a unique anti-SARS-CoV-2 gene signature. We identified for the first time that molecular pathways for heparin-binding, RAGE, miRNA, and PLA2 inhibitors were associated with SARS-CoV-2 infection. The NRCAM and SAA2 genes, which are involved in severe inflammatory responses, and the FGF1 and FOXO1 genes, which are associated with immune regulation, were found to be associated with the cellular gene response to SARS-CoV-2 infection. Moreover, several cytokines, most significantly IL-8 and IL-6, demonstrated key associations with SARS-CoV-2 infection. Interestingly, the only response gene that was shared among the five viral infections was SERPINB1. The protein-protein interaction (PPI) analysis shed light on genes with high interaction activity that SARS-CoV-2 shares with other viral infections. The findings showed that the genetic pathways associated with rheumatoid arthritis, the AGE-RAGE signaling system, malaria, hepatitis B, and influenza A were of high significance. We found that the virogenomic transcriptome of infection, gene modulation of host antiviral responses, and GO terms of SARS-CoV-2 and EBOV were more similar than to SARS, H1N1, and MERS. This work compares the virogenomic signatures of highly pathogenic viruses and provides valid targets for potential therapy against SARS-CoV-2.

Serum Vitamin D Levels in Children with Immune Thrombocytopenia

OBJECTIVE

Immune thrombocytopenia (ITP) is an acquired immuno-mediated disorder characterized by thrombocytopenia with an increased risk of bleeding. In recent years 1,25[OH]2D3 has been rediscovered as an immune modulator. We decided to evaluate serum Vitamin D levels in a cohort of children with immune thrombocytopenia in order to discover if Vitamin D concentrations may predict ITP duration.

METHODS

Thirty children were enrolled in this study (sixteen with chronic ITP and fourteen with newly diagnosed ITP) to assess serum Vitamin D levels.

RESULTS

The results showed that 80% of the enrolled children presented a D hypovitaminosis status. Children with newly diagnosis ITP showed no statistically significantly higher median values of Vitamin D compared to chronic ITP.

CONCLUSION

This study may suggest that Vitamin D deficiency does not represent a chronicity factor for ITP. However, further studies are needed to understand the role of Vitamin D in ITP pathogenesis.

Impact of Vitamin D Deficiency on COVID-19-A Prospective Analysis from the CovILD Registry

The novel Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is a global health concern. Vitamin D (VITD) deficiency has been suggested to alter SARS-CoV-2 susceptibility and the course of disease. Thus, we aimed to investigate associations of VITD status to disease presentation within the CovILD registry. This prospective, multicenter, observational study on long-term sequelae includes patients with COVID-19 after hospitalization or outpatients with persistent symptoms. Eight weeks after PCR confirmed diagnosis, a detailed questionnaire, a clinical examination, and laboratory testing, including VITD status, were evaluated. Furthermore, available laboratory specimens close to hospital admission were used to retrospectively analyze 25-hydroxyvitamin D levels at disease onset. A total of 109 patients were included in the analysis (60% males, 40% females), aged 58 ± 14 years. Eight weeks after the onset of COVID-19, a high proportion of patients presented with impaired VITD metabolism and elevated parathyroid hormone (PTH) levels. PTH concentrations were increased in patients who needed intensive care unit (ICU) treatment, while VITD levels were not significantly different between disease severity groups. Low VITD levels at disease onset or at eight-week follow-up were not related to persistent symptom burden, lung function impairment, ongoing inflammation, or more severe CT abnormalities. VITD deficiency is frequent among COVID-19 patients but not associated with disease outcomes. However, individuals with severe disease display a disturbed parathyroid-vitamin-D axis within their recovery phase. The proposed significance of VITD supplementation in the clinical management of COVID-19 remains elusive.

The Price of Immune Responses and the Role of Vitamin D in the Inner Ear

OBJECTIVE

In this review the authors discuss evidence from the literature concerning vitamin D and temporal bone diseases (benign paroxysmal positional vertigo [BPPV], Menière's disease [MD], vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss). Common features shared by Menière's disease, glaucoma, and the possible influence by vitamin D are briefly discussed.

DATA SOURCES, STUDY SELECTION

Publications from 1970 until recent times have been reviewed according to a keyword search (see above) in PubMed.

CONCLUSIONS

MD, BPPV, vestibular neuritis, idiopathic facial paralysis, idiopathic acute hearing loss may all have several etiological factors, but a common feature of the current theories is that an initial viral infection and a subsequent autoimmune/autoinflammatory reaction might be involved. Additionally, in some of these entities varying degrees of demyelination have been documented. Given the immunomodulatory effect of vitamin D, we postulate that it may play a role in suppressing an eventual postviral autoimmune reaction. This beneficial effect may be enhanced by the antioxidative activity of vitamin D and its potential in stabilizing endothelial cells. The association of vitamin D deficiency with demyelination has already been established in other entities such as multiple sclerosis and experimental autoimmune encephalitis. Mice without vitamin D receptor show degenerative features in inner ear ganglia, hair cells, as well as otoconia. The authors suggest further studies concerning the role of vitamin D deficiency in diseases of the temporal bone. Additionally, the possible presence and degree of demyelination in these entities will have to be elucidated more systematically in the future.

Effects of 1, 25-dihydroxy vitamin D3 on clinical symptoms, pro-inflammatory and inflammatory cytokines in calves with experimental pneumonia

1, 25-dihydroxycholecalciferol is recognized as a potent immune-modulator which can fight against the pathogens via the activation of vitamin D3 receptors (VDRs), as well as stimulating various cytokines in infectious diseases. In the present study, because of the vitamin D3 has an appropriate immunomodulatory, the effects of this vitamin on the levels of pre-inflammatory and anti-inflammatory cytokines have been investigated in calves with experimental pasteurellosis. This study was experimentally carried out on 10 Holstein crossbred male calves (2-4 months) that were divided into two groups. Prepared Pasteurella multocida (3 × 10⁹ CFU/mL) was inoculated in the trachea with a lavage catheter and then the treatment group was injected with 1, 25-dihydroxycholecalciferol after confirming pneumonia. Blood sampling, clinical symptoms scoring and radiological evaluation were recorded for both groups at different time intervals. The prescription of, vitamin D₃ to the treatment group caused a decline in clinical symptoms score and changed interstitial and alveolo-interstitial lung pattern to such a degree that it could recover in comparison with the control group. The concentrations of pro-inflammatory cytokines (i.e., IL-1β, IL-6, and TNF-α) and the chemokine (IL-8) showed a significant decrease in the treatment group while the concentration of IL-10 increased in the treatment groups following the vitamin D₃ injection (P = .001). The evidence from the current study suggests that vitamin D3 exert the immunomodulatory effects in infectious diseases through the regulation of cytokines and activation of VDR pathways to produce antimicrobial peptides.

Association of 25-hydroxy vitamin D with asthma and its severity in children: a case-control study

Background

Universally, asthma has high prevalence rates and this has led numerous studies done into its causes. Despite extensive study on asthma the association between 25-Hydroxy Vitamin D (25(OH) vit. D) and asthma remains uncertain. In this study, the associations of 25(OH) vit. D levels with asthma and with the severity of asthma were evaluated.

Methods

This was a case–control study performed in 2015 in the city of Isfahan. In this study 520 children were studied. Children with asthma were classified as cases and children who were referred for reasons other than respiratory problems and asthma were considered as controls. Serum 25 (OH) vit. D levels were then examined and compared between the two groups. Differences among groups were stated to be statistically significant when P-values < 0.05.

Results

There were 260 asthmatic children and 260 controls in the present study. The mean 25 (OH) vit. D levels in the case group was 25.5 ± 16.62 and  16.76 ± 31.40 the control group and this difference was statistically significant (P < 0.05). 25(OH) vit. D levels were found to be 28.05 ± 16.98 in non-severe asthma and 21.41 ± 15.20 in severe asthma. Consequently 25(OH) vit. D level had inverse relationship with asthma severity (P = 0.002).

Conclusions

As the results of this study showed, the lower level of 25(OH) vit. D correlated with the higher severity of asthma manifestations. Therefore, it is recommended that 25(OH) vit. D levels get routinely checked especially in severe asthma cases and if the deficiency presents, appropriate therapeutic measures be used to reduce the asthma severity.

The Influence of Vitamin D on Neurodegeneration and Neurological Disorders: A Rationale for its Physio-pathological Actions

Vitamin D is a steroid hormone implicated in the regulation of neuronal integrity and many brain functions. Its influence, as a nutrient and a hormone, on the physiopathology of the most common neurodegenerative diseases is continuously emphasized by new studies. This review addresses what is currently known about the action of vitamin D on the nervous system and neurodegenerative diseases such as Multiple Sclerosis, Alzheimer's disease, Parkinson's disease and Amyotrophic Lateral Sclerosis. Further vitamin D research is necessary to understand how the action of this "neuroactive" steroid can help to optimize the prevention and treatment of several neurological diseases.

The Vitamin D Receptor as Tumor Suppressor in Skin

Cutaneous malignancies including melanomas and keratinocyte carcinomas (KC) are the most common types of cancer, occurring at a rate of over one million per year in the United States. KC, which include both basal cell carcinomas and squamous cell carcinomas, are substantially more common than melanomas and form the subject of this chapter. Ultraviolet radiation (UVR), both UVB and UVA, as occurs with sunlight exposure is generally regarded as causal for these malignancies, but UVB is also required for vitamin D synthesis in the skin. Keratinocytes are the major cell in the epidermis. These cells not only produce vitamin D but contain the enzymatic machinery to metabolize vitamin D to its active metabolite, 1,25(OH)₂D, and express the receptor for this metabolite, the vitamin D receptor (VDR). This allows the cell to respond to the 1,25(OH)₂D that it produces. Based on our own data and that reported in the literature, we conclude that vitamin D signaling in the skin suppresses UVR-induced epidermal tumor formation. In this chapter we focus on four mechanisms by which vitamin D signaling suppresses tumor formation. They are inhibition of proliferation/stimulation of differentiation with discussion of the roles of hedgehog, Wnt/β-catenin, and hyaluronan/CD44 pathways in mediating vitamin D regulation of proliferation/differentiation, regulation of the balance between oncogenic and tumor suppressor long noncoding RNAs, immune regulation, and promotion of DNA damage repair (DDR).

The effect of vitamin D3 and paricalcitol on penicillin-induced epileptiform activity in rats

AIM

Epilepsy is a disease characterized by seizures which impair human life considerably. Vitamin D is of different systemic effects on metabolism and its deficiency is known to have a high prevalence among epilepsy patients. Paricalcitol, a vitamin D receptor agonist, has relatively fewer side effects. This study aimed to investigate the anticonvulsant effect of vitamin D₃ (cholecalciferol) and paricalcitol on penicillin-induced epileptiform activity.

METHOD

21 male Wistar rat weighing 180-240 g were used. After anesthetized by 1.25 g/kg urethane intraperitoneally (i.p.), rats were placed in the stereotaxic frame and tripolar electrodes were placed on the skull. The single microinjection of penicillin (2.5 μl, 500 IU, i.c.) into left sensorimotor cortex induced epileptiform activity. A single dose of 60.000 IU/kg (i.p.) vitamin D₃ was administered 14 days before intracortical penicillin (500 IU) injection. Paricalcitol (10 μg/kg, i.p.) was administered 30 min before intracortical penicillin (500 IU) administration and recorded for the following 180 min.

RESULTS

Vitamin D₃ pretreatment and paricalcitol diminished the frequency of epileptiform activity (p < 0.001) without changing the amplitude (p > 0.05) compared to the penicillin-injected group. Vitamin D₃ pretreatment and paricalcitol led to an important delay in the onset of penicillin-induced epileptiform activity (p < 0.001 and p < 0.05, respectively). Vitamin D₃ increased the latency of penicillin-induced epileptic activity compared to paricalcitol group (p < 0.001).

CONCLUSION

Results indicate that vitamin D₃ and paricalcitol decreased the frequency and increased the latency of the penicillin-induced epileptic activity. Vitamin D₃ was more effective than paricalcitol.

Effect of Oral Versus Intramuscular Vitamin D Replacement on Oxidative Stress and Outcomes in Traumatic Mechanical Ventilated Patients Admitted to Intensive Care Unit

BACKGROUND

This study aimed to evaluate the safety and efficacy of 2 forms of vitamin D supplementation on oxidative stress and weaning from the ventilator in patients with traumatic injury and vitamin D deficiency.

METHODS

Seventy-two patients were randomly divided into 3 groups: receiving 50,000 IU pearl cholecalciferol daily for 6 days, 1 intramuscular injection of 300,000 IU of cholecalciferol, or a control group that did not receive any supplement. Duration of mechanical ventilation, body composition, and biochemical biomarkers were measured before and after the intervention.

RESULT

At the end of the study, the mean serum 25(OH)D increased in the intervention groups compared with the control group (P < .05). The interleukin 6, erythrocyte sedimentation rate, C-reactive protein levels, Sequential Organ Failure Assessment score, duration of mechanical ventilation, and length of intensive care unit admission significantly decreased; however, total antioxidant capacity concentration did not differ significantly between the 2 intervention groups. Among the body composition variables, extracellular water ratio changes were statically different in oral vitamin D group compared with the control group (P = .001). No side effects were reported with the supplements.

CONCLUSIONS

Vitamin D administration improved clinical signs and biochemical biomarkers in a small group of patients with traumatic injury. Well-designed multicenter clinical studies with longer intervention duration are necessary for this field.

Vitamin D-regulated osteocytic sclerostin and BMP2 modulate uremic extraskeletal calcification

We induced chronic kidney disease (CKD) with adenine in WT mice, mice with osteocyte-specific deletion of Cyp27b1, encoding the 25-hydroxyvitamin D 1(OH)ase [Oct-1(OH)ase-/-], and mice with global deletion of Cyp27b1 [global-1α(OH)ase-/-]; we then compared extraskeletal calcification. After adenine treatment, mice displayed increased blood urea nitrogen, decreased serum 1,25(OH)2D, and severe hyperparathyroidism. Skeletal expression of Cyp27b1 and of sclerostin and serum sclerostin all increased in WT mice but not in Oct-1α(OH)ase-/- mice or global-1α(OH)ase-/- mice. In contrast, skeletal expression of BMP2 and serum BMP2 rose in the Oct-1α(OH)ase-/- mice and in the global-1α(OH)ase-/- mice. Extraskeletal calcification occurred in muscle and blood vessels of mice with CKD and was highest in Oct-1α(OH)ase-/-mice. In vitro, recombinant sclerostin (100 ng/mL) significantly suppressed BMP2-induced osteoblastic transdifferentiation of vascular smooth muscle A7r5 cells and diminished BMP2-induced mineralization. Our study provides evidence that local osteocytic production of 1,25(OH)2D stimulates sclerostin and inhibits BMP2 production in murine CKD, thus mitigating osteoblastic transdifferentiation and mineralization of soft tissues. Increased osteocytic 1,25(OH)2D production, triggered by renal malfunction, may represent a "primary defensive response" to protect the organism from ectopic calcification by increasing sclerostin and suppressing BMP2 production.

Severe Vitamin D Deficiency Increases Mortality Among Patients With Liver Cirrhosis Regardless of the Presence of HCC

BACKGROUND

The aim of this study was to investigate the association between vitamin D deficiency (<10 mg/ml) and mortality in patients with and without hepatocellular carcinoma (HCC) in a cohort of patients with liver cirrhosis.

MATERIALS AND METHODS

A prospective study was conducted among 345 patients with liver cirrhosis.

RESULTS

At enrolment, 46 (13.3%) patients had HCC. Severe vitamin D deficiency was associated with mortality (p<0.01). At the survival analysis, alpha-fetoprotein >10 ng/ml (p=0.003), vitamin D deficiency (p<0.001), a Model for End-Stage Liver Disease score ≥15 (p<0.001), Child-Pugh class B and C (versus A) (p<0.001) and the presence of active HCC (p<0.001) were strongly associated with death. At the multivariate Cox regression analysis, only Child-Pugh class B and C (versus A) and vitamin D deficiency were found to be significantly associated with death during the follow-up period (p<0.001 and p=0.006, respectively).

CONCLUSION

Vitamin D deficiency is common in patients with HCC, it is associated with active HCC and it negatively affects the overall survival of patients with cirrhosis.

Serum vitamin D and diabetic foot complications

Background: Foot complications such as ulceration and neuropathy are common complications of diabetes mellitus (DM). Previous reports have demonstrated a possible increased risk of these complications in diabetic patients with low levels of serum vitamin D.Objectctive: The purpose of this study is to compare serum vitamin D levels in diabetic patients with and without Charcot neuroarthropathy (CN), peripheral arterial disease (PAD), infection (DFI), ulceration (DFU), and peripheral neuropathy (DPN). Design: A retrospective chart review of all patients undergoing foot and ankle surgery with a history of DM over a 13 month period was performed. From this cohort, fifty subjects with CN were matched with 50 without CN and preoperative lab values were compared. A secondary evaluation was performed on the subjects' other comorbidities including PAD, DFI, DFU, and DPN. Results: Seventy-eight percent of our patients had vitamin D deficiency or insufficiency. Preoperative serum vitamin D levels were not significantly different between diabetic patients with and without CN (p = 0.55). Diabetic patients with PAD (p = 0.03), DFI (p = 0.0006), and DFU (p = 0.04) were all found to have significantly lower serum vitamin D levels than diabetic patients without these complications. Lower levels of serum albumin and higher serum creatinine were also noted with subjects with PAD, DFI, DPN, and DFU. While seasonal serum vitamin D level fluctuation was noted, this difference did not reach statistical significance with the numbers available. Conclusion: We found various lower extremity complications to be associated with low serum vitamin D including PAD, DFI, and DFU. While other studies have questioned the role of vitamin D and CN, we were unable to identify any significant difference between diabetic patients with and without Charcot neuroarthropathy. Level of evidence: Level 2.

Rare paleopathological insights into vitamin D deficiency rickets, co-occurring illnesses, and documented cause of death in mid-19th century London, UK

Growing evidence suggests that vitamin D supports immune responses to infections, autoimmune conditions and cancers, although evidence from large-scale studies is limited. There is scope to better understand how vitamin D deficiency interacted with other diseases to affect health in past groups. This study investigated paleopathological evidence and documentary records of individual cause of death to examine disease co-occurrence in a group of mid-19th century child burials from London, UK. Twenty-one percent of children had vitamin D deficiency rickets (138/642) and 36 children with rickets had an identified cause of death. Cyclical episodes of metabolic and nutritional deficiencies (rickets and scurvy) had occurred during childhood. Active rickets co-occurred with respiratory and gastrointestinal infections in a small number of children, likely reflecting vitamin D's role in supporting immune function. Consideration of the stage of the vitamin D deficiency showed that the majority of children were affected by chronic disease loads indicative of multiple episodes of illness. Reconstructions of the wider health consequences of vitamin D deficiency in past groups are dependent on recognising whether the deficiency was active or healed. The variability of diseases identified illustrates the high disease burden that affected children in this socially disadvantaged group.

Vitamin D and the Athlete: Current Perspectives and New Challenges

The last decade has seen a dramatic increase in general interest in and research into vitamin D, with many athletes now taking vitamin D supplements as part of their everyday dietary regimen. The most recognized role of vitamin D is its regulation of calcium homeostasis; there is a strong relationship between vitamin D and bone health in non-athletic individuals. In contrast, data have consistently failed to demonstrate any relationship between serum 25[OH]D and bone health, which may in part be due to the osteogenic stimulus of exercise. Vitamin D may interact with extra-skeletal tissues such as muscle and the immune system to modulate recovery from damaging exercise and infection risk. Given that many athletes now engage in supplementation, often consuming extreme doses of vitamin D, it is important to assess whether excessive vitamin D can be detrimental to health. It has been argued that toxic effects only occur when serum 25[OH]D concentrations are greater than 180 nmol·l^-1, but data from our laboratory have suggested high-dose supplementation could be problematic. Finally, there is a paradoxical relationship between serum 25[OH]D concentration, ethnicity, and markers of bone health: Black athletes often present with low serum 25[OH]D without physiological consequences. One explanation for this could be genetic differences in vitamin D binding protein due to ethnicity, resulting in greater concentrations of bioavailable (or free) vitamin D in some ethnic groups. In the absence of any pathology, screening may be unnecessary and could result in incorrect supplementation. Data must now be re-examined, taking into consideration bioavailable or "free" vitamin D in ethnically diverse groups to enable new thresholds and target concentrations to be established; perhaps, for now, it is time to "set vitamin D free".

No effects without causes: the Iron Dysregulation and Dormant Microbes hypothesis for chronic, inflammatory diseases

Since the successful conquest of many acute, communicable (infectious) diseases through the use of vaccines and antibiotics, the currently most prevalent diseases are chronic and progressive in nature, and are all accompanied by inflammation. These diseases include neurodegenerative (e.g. Alzheimer's, Parkinson's), vascular (e.g. atherosclerosis, pre-eclampsia, type 2 diabetes) and autoimmune (e.g. rheumatoid arthritis and multiple sclerosis) diseases that may appear to have little in common. In fact they all share significant features, in particular chronic inflammation and its attendant inflammatory cytokines. Such effects do not happen without underlying and initially 'external' causes, and it is of interest to seek these causes. Taking a systems approach, we argue that these causes include (i) stress-induced iron dysregulation, and (ii) its ability to awaken dormant, non-replicating microbes with which the host has become infected. Other external causes may be dietary. Such microbes are capable of shedding small, but functionally significant amounts of highly inflammagenic molecules such as lipopolysaccharide and lipoteichoic acid. Sequelae include significant coagulopathies, not least the recently discovered amyloidogenic clotting of blood, leading to cell death and the release of further inflammagens. The extensive evidence discussed here implies, as was found with ulcers, that almost all chronic, infectious diseases do in fact harbour a microbial component. What differs is simply the microbes and the anatomical location from and at which they exert damage. This analysis offers novel avenues for diagnosis and treatment.

Association of vitamin D deficiency with an increased risk of late-onset neonatal sepsis

BACKGROUND

Vitamin D deficiency in mothers and neonates is being recognised increasingly as a leading cause of many adverse health effects in the newborn infant, including sepsis.

METHODS

A prospective observational study was conducted at a tertiary care Paediatric teaching hospital in northern India to assess vitamin D deficiency as a possible risk factor for late-onset sepsis (LOS) in term and late preterm neonates and also to examine the correlation between maternal and infant vitamin D levels during the neonatal period. Late-onset sepsis (LOS) was defined as the development of signs and symptoms of severe sepsis after 72 h of life and a positive sepsis screen. All term and late preterm neonates admitted with LOS between September 2015 and February 2016 who had not been previously admitted for >48 h and had not been prescribed antibiotics or vitamin D were included in the study. Matched controls were recruited from otherwise healthy neonates admitted with physiological hyperbilirubinaemia. Serum 25(OH) vitamin D was assessed in neonates in both groups and their mothers.

RESULTS

A total of 421 neonates were admitted to the neonatal intensive care unit during the study period, 120 of whom satisfied the inclusion criteria, and 60 were recruited as cases. Sixty neonates were recruited as controls who were similar in gender, gestational age, age at admission and anthropometry. The study group had significantly lower mean (SD) vitamin D levels [15.37 ng/ml (10.0)] than the control group [21.37 ng/ml (9.53)] (p = 0.001). The odds ratio was 1.7 (95% CI 0.52-5.51) for LOS in vitamin D-deficient neonates. Mothers of septic neonates also had significantly lower mean (SD) vitamin D levels [17.87 (11.89)] than the mothers of non-septic neonates [23.65 ng/ml (9.55)] (p = 0.004). Maternal vitamin D levels strongly correlated to neonatal vitamin D levels in both groups.

CONCLUSION

Neonates with vitamin D deficiency are at greater risk of LOS than those with sufficient vitamin D levels.

Vitamin D and critical illness outcomes

PURPOSE OF REVIEW

Although low vitamin D levels have been shown to be a risk factor for adverse outcomes in critical care, it is not clear to date if supplementation can alter such outcomes in all ICU patients. The focus of vitamin D research now is on interventional trials to identify a critically ill patient subset who may benefit from high-dose vitamin D supplementation.

RECENT FINDINGS

The VITdAL-ICU trial, a randomized, double-blind, placebo-controlled, single center trial of 475 heterogeneous critically ill patients, did not show improvement in hospital length of stay or overall mortality but did demonstrate in a secondary outcome that high-dose oral vitamin D3 improved mortality in patients with severe vitamin D deficiency.

SUMMARY

Vitamin D supplementation may represent a personalized and targeted therapy for critical illness. Vitamin D regulates over 1000 genes in the human genome, and the mechanism of action is influenced by gene polymorphisms and epigenetics. The study of the metabolomics, transcriptomics and epigenetics of vitamin D status and supplementation holds promise generating insights into critical illness outcomes.

Immunomodulatory Role of Vitamin D: A Review

Vitamin D is well known for its classical hormonal action related to the maintenance of mineral and skeletal homeostasis. However, the discovery that vitamin D receptor (VDR) is expressed in most non-skeletal tissues points to its broad role in the human organism. Current literature emphasizes a multidirectional role of vitamin D, with a special focus on its immunomodulatory properties. As VDR and the enzyme 1-α-hydroxylase are expressed in most immune cells, vitamin D modulates the phagocytic activity of macrophages and natural killer cells. In addition, it induces the microbicidal activity of phagocytes. In contrast, vitamin D suppresses differentiation and maturation of antigen-presenting dendritic cells and B lymphocytes, and it inhibits proliferation of Th1 and Th17 cells. In this review we aimed to describe the current scientific discoveries on the role of vitamin D as immunomodulator.

Alternative Oral Agents in Prophylaxis and Therapy of Uterine Fibroids-An Up-to-Date Review

Uterine fibroids (UFs) are the most common tumors of the female genital tract. The effect of UFs on the quality of life and the overall cost of treatment are significant issues worldwide. Tumor size and location are the two specific factors which influence the occurrence of symptoms, the need for, and method of, treatment (some tumors require surgery while some can be treated with selected drugs). Primary prevention and treatment of early UF disease are worthy goals that might have a great impact on health care systems. Several treatments and prophylactic methods can be used in this endeavor. This publication presents current data about lesser-known substances which may have a beneficial effect on the treatment or prophylaxis of UFs and can be administered orally, serving as an alternative to (or complement of) surgery or selective progesterone receptor modulators (SPRMs). Early prevention and treatment of UFs in women from high-risk groups should be our priority. Innovative forms of UF management are under intensive investigation and may be promising options in the near future. Many of them evaluated vitamin D, paricalcitol, epigallocatechin gallate (EGCG), elagolix, aromatase inhibitors (AIs), and cabergoline and deemed them to be safe and effective. The next step in such projects should be properly constructed randomized control trials (RCTs), carried out by successive phases.