Vitamin D discovery outpaces FDA decision making

Association of Helicobacter pylori Infection with Papillary Thyroid Carcinoma: A Case-control Study

Background: The thyroid nodules incidence has risen worldwide. Although factors such as increasing the use of imaging techniques and more rapid detection of small thyroid nodules have been implicated in the recent rise in thyroid cancer incidence, some environmental parameters such as infectious agents may be involved. Helicobacter pylori infection is an environmental risk factor, which may mimic the antigenic properties of membranes of thyrocytes. Objectives: This study aimed at evaluating the association of H. pylori infection with benign and malignant thyroid nodules in comparison with the control group. Methods: Patients with benign thyroid nodules, papillary thyroid cancer (PTC), and euthyroid healthy controls without thyroid nodules that had just been diagnosed were included in the study. All participants underwent clinical examination. Various biochemical parameters such as serum H. pylori Ab (IgG) and thyroid function tests were measured. Comparisons were made between groups. Results: Finally, 370 patients with benign thyroid nodules, 364 patients with PTC, and 360 healthy subjects without nodules participated as a control group. In the patients with PTC, the prevalence of H. pylori infection was 89.6%, while in the group of patients with benign thyroid nodules and the control group was 81.1% and 75%, respectively (P < 0.001). Helicobacter pylori antibody (Ab) titer was not significantly associated with any of the anthropometric and biochemical variables. Conclusions: Helicobacter pylori infection was significantly higher in patients with benign thyroid nodules and PTC than in the control group. Also, the rate of infection was significantly higher in the malignant nodule group than in the benign thyroid nodules group.

Thinking About Pathomechanisms and Current Treatment of Erectile Dysfunction-"The Stanley Beamish Problem." Review, Recommendations, and Proposals

INTRODUCTION

Up to 50% of all men over 50 years of age suffer from erectile dysfunction. Since the late 1990s erectile dysfunction has been treated mostly with phosphodiesterase 5 inhibitors (PDE5I). Over the past 20 years, numerous scientific findings on the development of erectile dysfunction have been collected, which have so far received little attention in the treatment of erectile dysfunction.

OBJECTIVES

The objectives of this study were to review the existing medical literature on erectile dysfunction regarding physiology, pathophysiology, and especially therapeutic options beyond treatment with PDE5I and to enable a more effective and especially sustainable treatment for erectile dysfunction.

METHODS

A literature review was performed by using PubMed from 1985 to 2020 regarding the physiology, pathophysiology, and treatment of erectile dysfunction.

RESULTS

Since the end of the 1990s an enormous amount of knowledge has been gained about the physiology/pathophysiology of erection/erectile dysfunction. Based on these findings, numerous physical, drug, and holistic therapeutic options (beyond the application of PDE5I) have been developed for the treatment of erectile dysfunction. However, these are still relatively rarely used in the therapeutic concept of erectile dysfunction today.

CONCLUSION

Based on scientific findings of the last 20 years, there are numerous therapeutic approaches, including lifestyle modification, specific pelvic floor exercises, shock wave treatment, and the application of different supplements. The long-term treatment of erectile dysfunction should now go beyond the purely symptomatic use of PDE5I. W-D Beecken, M Kersting, W Kunert, et al. Thinking About Pathomechanisms and Current Treatment of Erectile Dysfunction-"The Stanley Beamish Problem." Review, Recommendations, and Proposals. Sex Med Rev 2021;9:445-463.

Vitamin D Supplementation As a Potential therapeutic Mediator in Asthma: Does Dose Really Matter? a Critical Review of the Literature

Around 400 million people across the globe will suffer from asthma in the next 10 years. Although most asthmatics use asthma medications regularly, they occasionally visit the emergency department for aggressive treatment amidst family anxiousness. Vitamin D (VD) not only regulates the expression of genes associated with calcium homeostasis, but also the genes associated with cancers, autoimmune diseases, and infection. VD has also non-genomic activities e.g. it is a potentially safe and effective novel strategy for decreasing the asthma episodes and controlling exacerbations. Our review assessed the dose, serum level, duration of administration and outcomes of VD in cases of asthmas. Although a body of research evidences the effectiveness of VD supplementation in asthma, other studies showed the insignificant response of VD to asthma either with low dose or low achieved serum VD levels. Nevertheless, recent reviews suggest that manipulating VD status holds promise for primary prevention and treatment of asthma. Future research on the relationship between VD and asthma should consider utilizing adequate doses of VD preparations for sufficient duration (likely to be >12 months) aiming to achieve appropriate level of serum VD (25-hydroxyvitamin D) concentration (likely to be at least >40 ng/mL).

Oral Vitamin D Supplementation to Mothers During Lactation-Effect of 25(OH)D Concentration on Exclusively Breastfed Infants at 6 Months of Age: A Randomized Double-Blind Placebo-Controlled Trial

Background: Exclusively breastfed infants are at risk of vitamin D deficiency. Objective: To find out proportion of exclusively breastfed infants having serum 25(OH)D concentration <11 ng/mL at 6 months of age with or without oral supplementation of vitamin D₃ to lactating mothers. Methods: Randomized placebo-controlled study included 132 mothers and infants divided into two groups. Mothers received either vitamin D₃ 60,000 IU between 24 and 48 hours postpartum and at 6, 10, and 14 weeks amounting to 240,000 IU of vitamin D₃ or placebo. Serum 25(OH)D concentration in the mothers was measured at recruitment and that of infants, at birth and 6 months. Infants were evaluated for rickets at 6 months. Findings: Total 114 mother-infant dyads followed. Subjects in both groups were comparable in basic characteristics. At 6 months of age, serum 25(OH)D concentration in infants was 18.93 (5.12) ng/mL in the intervention group and 6.43 (3.76) ng/mL in the control group (mean difference = 12.5; 95% CI = 10.80-14.17; p < 0.001) and vitamin D deficiency and insufficiency was corrected in 93.1% and 38% infants, respectively, in the intervention group. There was no change in the vitamin D status of infants in the control group. In 60.3% infants (RR = 0.519; 95% CI = -0.485 to 0.735) of the intervention group 25(OH)D concentration was <20 ng/mL at 6 months of age. Six infants in the control group suffered from biochemical rickets. Radiological rickets developed in one infant in the intervention group and two infants in the control group. Conclusion: Serum 25(OH)D concentration of exclusively breastfed infants rise significantly when mothers are orally supplemented with 240,000 IU of vitamin D₃ during lactation in comparison with the infants of unsupplemented mothers with 94.6% and 48.1% reduction in the risk of vitamin D deficiency and insufficiency, respectively, at 6 months of age.

Vitamin D and Male Erectile Function: An Updated Review

Literature support that vitamin-D is important for different systems of the human body including, but not limited to endocrine and immune systems, vasculature and endothelial function of the body. Male erectile function depends on many factors and can be perceived as a health indicator of the body. Epidemiological data have shown that vitamin-D deficiency is also associated with erectile dysfunction. In this review, our aim is to interpret the mechanisms by which vitamin-D might regulate anatomy and physiology of penis. Evidence showed that vitamin-D is needed for an adequate erectile function. Briefly, vitamin-D is crucial for a better healthy body and sexual activity.

Serum Admission 25-Hydroxyvitamin D Levels and Outcomes in Initially Non-Septic Critically Ill Patients

INTRODUCTION

To examine whether very low levels of 25-hydroxyvitamin D {25(OH)D} upon admission to the intensive care unit (ICU) are associated with worse outcomes.

METHODS

Retrospective observational cohort study of critically ill patients treated in a multidisciplinary ICU. Two hundred twenty seven initially non-septic, critically ill patients, in whom 25-hydroxyvitamin D was measured at ICU admission. An additional group of 192 healthy subjects was also used. Patients were categorized according to their vitamin D levels at admission; the two patient groups were those with severely low 25-hydroxyvitamin D levels (<7 ng/mL, N = 101) and those with vitamin D levels ≥7 ng/mL, N = 126.

RESULTS

ICU admission 25-hydroxyvitamin D levels of critically ill patients were much lower than those of healthy subjects (P < 0.0001). The median time to sepsis for the two patient groups did not differ, nor did the length of ICU stay (days). Both groups exhibited similar hospital mortality rates. However, among the fraction of patients who eventually became septic (N = 145), the odds ratio (OR) for developing respiratory infections in patients with admission vitamin levels < 7 ng/mL compared with patients with admission vitamin D levels ≥7 ng/mL was 5.25 {95% confidence interval (CI) 1.5-18.32, P = 0.009}.

CONCLUSIONS

Initially non-septic critically ill patients appear to have very low ICU admission 25-hydroxyvitamin D levels. Among critically ill patients, severely low vitamin D levels (<7 ng/mL) at ICU admission do not predict sepsis development, increased risk of in-hospital mortality, or longer stay in the ICU. However, these severely low admission vitamin D levels in patients who will eventually develop sepsis are associated with development of respiratory tract infections.

Evaluation and comparison of Vitamin D receptors in periodontal ligament tissue of Vitamin D-deficient chronic periodontitis patients before and after supplementation of Vitamin D3

Background:

Vitamin D, an important hormone required by the body, exerts its biological effects through Vitamin D receptors (VDRs) present on target cells. Vitamin D is ineffective in tissues which lack VDR. Various tissues show the presence of VDRs. However, evidence for the presence of VDRs in human periodontal ligament tissue in fully erupted teeth in adults is lacking. The present study intends to evaluate the presence of VDRs in periodontal ligament (PDL) tissue and assess their response to serum Vitamin D3 levels in chronic periodontic patients.

Materials and Methods:

A total of 19 chronic periodontitis patients were enrolled in the study and tested for serum 25(OH)D3 levels. Deficient patients were supplemented with Vitamin D3. PDL tissue of these patients was isolated after tooth extraction before and after supplementation of Vitamin D3 and analyzed for the presence of VDR in PDL tissue by using enzyme-linked immunosorbent assay.

Results:

All the chronic periodontitis patients were found to be deficient in Vitamin D3. The mean serum 25(OH)D3 level before supplementation was 13.96 ng/mL which significantly increased to 35.12 ng/mL after supplementation of Vitamin D3 for 6 weeks. VDR analysis determined mean VDR conc. in PDL tissue to be -1.443 ng/mL, which increased to 2.38 ng/mL after supplementation. A concentration dependent correlation was seen between serum 25(OH)D3 levels and VDR conc. in PDL tissue after supplementation.

Conclusions:

The study determined Vitamin D Receptors (VDR) in PDL tissue after supplementation of Vitamin D. Thus in addition to the standard treatment modalities, Vitamin D3 supplementation would be an important factor for generation of adequate immune response.

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.

The vitamin D receptor and the etiology of RANTES/CCL-expressive fatty-degenerative osteolysis of the jawbone: an interface between osteoimmunology and bone metabolism

BACKGROUND

Recent research on vitamin D indicates that our current understanding of the factors leading to chronic inflammation should be revised. One of the key mechanisms by which microbial immunosuppression occurs is the suppression of one of the most common endogenous cell nucleus receptors: the vitamin D receptor (VDR). Autoimmune diseases may be correlated with VDR deactivation (VDR-deac) which occurs when the receptor is no longer able to transcribe antimicrobial agents. Excess 1,25-dihydroxyvitamin D (1,25D) is not converted to 25-hydroxyvitamin D (25D); thus, high 1,25D levels may be accompanied by low 25D values.

PATIENTS AND METHODS

Since 1,25D promotes osteoclast activity and may thereby cause osteoporosis, fatty-degenerative osteolysis of the jaw (FDOJ), as described by our team, may also be associated with VDR-deac. In 43 patients, vitamin D conversion, immune system function and the quality of bone resorption and formation in the jawbone were related factors that may enhance chronic inflammatory processes. Here, we examine the relationship between immunology and bone metabolism among 43 FDOJ patients and those with immune system diseases (ISDs).

RESULTS

We provide a link between FDOJ, RANTES/CCL5 overexpression and VDR-deac.

CONCLUSION

The clinical data demonstrate the interaction between VDR-deac and proinflammatory RANTES/CCL5 overexpression in FDOJ patients.

A Bacterial Component to Alzheimer's-Type Dementia Seen via a Systems Biology Approach that Links Iron Dysregulation and Inflammagen Shedding to Disease

The progression of Alzheimer's disease (AD) is accompanied by a great many observable changes, both molecular and physiological. These include oxidative stress, neuroinflammation, and (more proximal to cognitive decline) the death of neuronal and other cells. A systems biology approach seeks to organize these observed variables into pathways that discriminate those that are highly involved (i.e., causative) from those that are more usefully recognized as bystander effects. We review the evidence that iron dysregulation is one of the central causative pathway elements here, as this can cause each of the above effects. In addition, we review the evidence that dormant, non-growing bacteria are a crucial feature of AD, that their growth in vivo is normally limited by a lack of free iron, and that it is this iron dysregulation that is an important factor in their resuscitation. Indeed, bacterial cells can be observed by ultrastructural microscopy in the blood of AD patients. A consequence of this is that the growing cells can shed highly inflammatory components such as lipopolysaccharides (LPS). These too are known to be able to induce (apoptotic and pyroptotic) neuronal cell death. There is also evidence that these systems interact with elements of vitamin D metabolism. This integrative systems approach has strong predictive power, indicating (as has indeed been shown) that both natural and pharmaceutical iron chelators might have useful protective roles in arresting cognitive decline, and that a further assessment of the role of microbes in AD development is more than highly warranted.

The role of vitamin D supplementation on erectile function

In the last few years growing evidence highlighted vitamin D (VD) deficiency is one of the several dynamics that associates with increased atherosclerotic cardiovascular (ASCV) diseases. ASCV diseases and erectile dysfunction (ED) share common risk factors such as diabetes mellitus, hypertension, smoking, hyperlipidemia, and a sedentary lifestyle. The aim of this review was to summarize current progress in VD research by focusing effect of low VD level on different body systems and erectile function. Here we examine research linking VD deficiency and ED and discuss how VD influences ED and its classic risk factors that also associate to increased ED risk. We also summarize research indicating that VD associates with reduced risk of several nonvascular contributing factors for ED. Available literature demonstrates relatively high rates of low VD serum levels in ED patients. Based on the preclinical and clinical data available in the literature, to date, we infer that VD play a critical role in maintaining erectile function in humans. Nevertheless, this should also be tested through randomized controlled studies on the effect of VD supplementation with larger population.

Vitamin D treatment improves levels of sexual hormones, metabolic parameters and erectile function in middle-aged vitamin D deficient men

BACKGROUND

The associations between serum vitamin D (VD), serum testosterone (TT) and metabolic syndrome are complex and with limited published research, particularly on the effects of VD treatment on sexual hormones, erectile function and the metabolic syndrome.

OBJECTIVES

This study assessed whether a monthly high dose VD treatment for 12 months in VD deficient middle-aged men was associated with: changes in levels of sexual hormones, improvement of diabetes control and metabolic syndrome components, better erectile function [International Index of Erectile Function (IIEF)-5 questionnaire]; and changes in a prostate marker.

MATERIALS AND METHODS

Descriptive research of a prospective study, conducted between October 2014 and September 2015, 102 male patients ≥35 [(±SD: 53.2 ± 10.5), (range 35-64)] years with deficient serum VD level (<30 ng/mL) were included in the study. Participants were followed up for one year, with monitoring at 3-, 6-, 9- and 12-months. At the initial baseline visit, a complete medical examination was conducted, and blood was drawn for laboratory tests for above biochemical and hormonal variables under examination. Participants received an initial VD (Ergocalciferol; oral solution 600 000 IU/1.5 ml), and followed a VD treatment regime thereafter. At the four follow up visits (3, 6, 9 and 12 months), blood was collected, and patients' erectile function was evaluated by IIEF-5 questionnaire.

MAIN OUTCOME MEASURES

During the follow up visits, all the biochemical and hormonal (TT, estradiol and luteinizing hormones, HbA1c, serum lipids profile) were assessed, and patients' erectile function was evaluated by IIEF-5 questionnaire.

RESULTS

Patients' mean age was 53.2 ± 10.4 years. Serum VD exhibited significant increments (p <0.001) from baseline (15.16 ± 4.64 ng/mL), to 3 (31.90 ± 15.99 ng/mL), 6 (37.23 ± 12.42 ng/mL), 9 (44.88 ± 14.49 ng/mL) and 12 months (48.54 ± 11.62 ng/mL), and there was significant stepladder increases in both serum TT level (12.46 ± 3.30 to 15.99 ± 1.84 nmol/L) and erectile function scores (13.88 ± 3.96 to 20.25 ± 3.24) (p <0.001 for both). We also observed significant stepladder decreases in estradiol (87.90 ± 27.16 to 69.85 ± 14.80 pmol/L, p = 0.001), PTH (from 58.52 ± 28.99 to 38.33 ± 19.44 pg/mL, p <0.001) and HbA1c levels (7.41 ± 2.85 to 6.66 ± 1.67%, p = 0.001). Mean BMI significantly decreased from 33.91 ± 6.67 to 33.14 ± 6.35 kg/m² (p = 0.001); and PSA values significantly increased from 0.59 ± 0.30 to 0.82 ± 0.39 ng/mL (p <0.001) at the end of the 12 months' follow-up. There were no changes in LH levels.

CONCLUSION

This study demonstrated that VD treatment improves testosterone levels, metabolic syndrome and erectile function in middle-aged men. More randomized placebo-controlled interventional trials of VD treatment in patients with the metabolic syndrome and low TT could assist in uncovering the putative roles of VD.

Vitamin D receptor gene FokI but not TaqI, ApaI, BsmI polymorphism is associated with Hashimoto's thyroiditis: a meta-analysis

Four VD receptor (VDR) gene polymorphisms (TaqI, ApaI, FokI and BsmI) have been reported to influence Hashimoto’s thyroiditis (HT) risk. However, individual studies have produced inconsistent results. We conducted a comprehensive meta-analysis of eleven case-control studies to better understand roles of the four polymorphisms in HT development. The results showed only FokI polymorphism was significantly associated with the risk of HT (F vs f: OR = 1.44, 95% CI = 1.09–1.91, P = 0.010; FF vs Ff + ff: OR = 1.72, 95% CI = 1.09–2.70, P = 0.019). Subgroup analyses demonstrated the significant effect was only present in Asian population (F vs f: OR = 1.45, 95% CI = 1.07–1.95, P = 0.016; FF vs ff: OR = 1.64, 95% CI = 1.03–2.59, P = 0.036; FF + Ff vs ff: OR = 1.34, 95% CI = 1.00–1.80, P = 0.047; FF vs Ff + ff: OR = 1.64, 95% CI = 1.03–2.64, P = 0.039), but not in Caucasian. For TaqI, ApaI and BsmI polymorphisms, no significant association was found in any model comparison. Based on the current literature, it appears that only VDR FokI polymorphism is associated with HT risk in Asian population, but not in Caucasians; and the TaqI, ApaI and BsmI polymorphisms have not positive association neither in the overall population, nor when stratified by ethnicity. Further well-designed studies with larger sample sizes and different ethnic population are needed to clarify the present findings.

Mucosal Interactions between Genetics, Diet, and Microbiome in Inflammatory Bowel Disease

Numerous reviews have discussed gut microbiota composition changes during inflammatory bowel diseases (IBD), particularly Crohn’s disease (CD). However, most studies address the observed effects by focusing on studying the univariate connection between disease and dietary-induced alterations to gut microbiota composition. The possibility that these effects may reflect a number of other interconnected (i.e., pantropic) mechanisms, activated in parallel, particularly concerning various bacterial metabolites, is in the process of being elucidated. Progress seems, however, hampered by various difficult-to-study factors interacting at the mucosal level. Here, we highlight some of such factors that merit consideration, namely: (1) the contribution of host genetics and diet in altering gut microbiome, and in turn, the crosstalk among secondary metabolic pathways; (2) the interdependence between the amount of dietary fat, the fatty acid composition, the effects of timing and route of administration on gut microbiota community, and the impact of microbiota-derived fatty acids; (3) the effect of diet on bile acid composition, and the modulator role of bile acids on the gut microbiota; (4) the impact of endogenous and exogenous intestinal micronutrients and metabolites; and (5) the need to consider food associated toxins and chemicals, which can introduce confounding immune modulating elements (e.g., antioxidant and phytochemicals in oils and proteins). These concepts, which are not mutually exclusive, are herein illustrated paying special emphasis on physiologically inter-related processes.

Plasma vitamin D levels and inflammation in the aortic wall of patients with coronary artery disease with and without inflammatory rheumatic disease

OBJECTIVES

Vitamin D modulates inflammation, and this may explain the observed associations between vitamin D status and disorders driven by systemic inflammation, such as coronary artery disease (CAD) and inflammatory rheumatic diseases (IRDs). The aims of this study were to assess vitamin D status in patients with CAD alone and in patients with CAD and IRD, and to explore potential associations between vitamin D status and the presence of mononuclear cell infiltrates (MCIs) in the aortic adventitia of these patients.

METHOD

Plasma levels of 25-hydroxyvitamin D₃ [(25(OH)D₃] were determined by radioimmunoassay and 1,25-dihydroxyvitamin D₃ [1,25(OH)₂D₃] by enzyme immunoassay in the 121 patients from the Feiring Heart Biopsy Study (FHBS) who had available histology data on adventitial MCIs; 53 of these had CAD alone and 68 had CAD and IRD.

RESULTS

In the crude analysis, vitamin D levels were similar in CAD patients with and without IRD. After adjustment for potential confounders, IRD was associated with an increase of 8.8 nmol/L [95% confidence interval (CI) 1.0-16.6; p = 0.027] in 25(OH)D₃ and an increase of 18.8 pmol/L (95% CI 4.3-33.3; p = 0.012) in 1,25(OH)₂D₃, while MCIs in the aortic adventitia were associated with lower levels of 1,25(OH)₂D₃ (β = -18.8, 95% CI -33.6 to -4.0; p = 0.014).

CONCLUSIONS

IRD was associated with higher levels of both 25(OH)D₃ and 1,25(OH)₂D₃. These findings argue against the hypothesis that patients with high systemic inflammatory burden (CAD+IRD) should have lower vitamin D levels than those with less inflammation (CAD only). Of note, when controlled for potential confounders, low 1,25(OH)₂D₃ levels were associated with adventitial aortic inflammation.

Low levels of serum Vitamin D in chronic periodontitis patients with type 2 diabetes mellitus: A hospital-based cross-sectional clinical study

Aim:

Vitamin D is associated with inflammatory diseases such as periodontal disease and diabetes mellitus (DM). The aim of our study was to find out the level of serum Vitamin D in chronic periodontitis patients (CHP) with and without type 2 DM.

Materials and Methods:

This study consists of 141 subjects, including 48 controls. Case groups consisted of 43 chronic periodontitis patients with type 2 DM (CHPDM) and 50 CHP. pocket depth (PD), clinical attachment loss (CAL), modified gingival index (MGI), plaque index (PI), and calculus index (CI) were taken. Serum 25-hydroxyvitamin D (25[OH] D) level in ηg/ml was estimated by electrochemiluminescence immunoassay with Elecsys and cobase e immunoassay analysers(cobase e 411). Other laboratory investigations including fasting blood sugar (FBS) and serum calcium were measured in all subjects.

Results:

The mean serum 25(OH) D level was 22.32 ± 5.76 ηg/ml, 14.06 ± 4.57 ηg/ml and 16.94 ± 5.58 ηg/ml for control, CHPDM and CHP groups respectively. The difference was statistically significant (P < 0.05). The mean value of FBS was significantly high in CHPDM group as compared to CHP group. Periodontal parameters like MGI, PI, PD, and CI showed significant difference between groups (P < 0.05) and higher score was found in CHP group, while CAL and PI showed no statistically significant difference between CHP and CHPDM group (P > 0.05).

Conclusions:

This study observed a low level of serum Vitamin D level in patients with CHP and CHPDM. Low Vitamin D level was observed in case groups may be due to the diseases process rather than low Vitamin D acting as a cause for the disease.

Aging and a long-term diabetes mellitus increase expression of 1 α-hydroxylase and vitamin D receptors in the rat liver

Diabetes mellitus (DM) is a metabolic disorder associated with serious liver complications. As a metabolic chronic disease, DM is very common in the elderly. Recent studies suggest ameliorating effects of vitamin D on metabolic and oxidative stress in the liver tissue in an experimental model of DM. The aim of this study was to investigate the expression of vitamin D receptors (VDRs) and 1α-hydroxylase, the key enzyme for the production of active vitamin D form (calcitriol) in the liver during long-term diabetes mellitus type 1 (DM1) in aging rats. We performed immunohistochemical analysis of liver expression of 1α-hydroxylase and VDRs during aging in long-term streptozotocin-induced DM1. 1α-Hydroxylase was identified in the monocyte/macrophage system of the liver. In addition to the nuclear expression, we also observed the expression of VDR in membranes of lipid droplets within hepatocytes. Aging and long-term DM1 resulted in significant increases in the number of 1α-hydroxylase immunoreactive cells, as well as the percentage of strongly positive VDR hepatocytes. In conclusion, the liver has the capacity for active vitamin D synthesis in its monocyte/macrophage system that is substantially increased in aging and long-term diabetes mellitus. These conditions are also characterized by significant increases in vitamin D receptor expression in hepatocytes. The present study suggests that VDR signaling system could be a potential target in prevention of liver complications caused by diabetes and aging.

Vitamin D Deficiency and Hashimoto's Thyroiditis in Children and Adolescents: a Critical Vitamin D Level for This Association?

OBJECTIVE

Vitamin D has been suggested to be active as an immunomodulator in autoimmune diseases such as Hashimoto's thyroiditis (HT). The goal of the present study was to investigate the vitamin D status in HT patients.

METHODS

This prevalence case-control study was conducted on 90 patients with HT (of ages 12.32 ± 2.87 years) and 79 age-matched healthy controls (11.85 ± 2.28 years). Serum 25-hydroxyvitamin D3 [25(OH)D3] levels were measured in all 169 subjects.

RESULTS

The prevalence of vitamin D deficiency in HT patients (64 of 90; 71.1%) was significantly higher than that in the control group (41 of 79; 51.9%) (p=0.025). Mean serum 25(OH)D3 level in the HT group was significantly lower compared to the control group (16.67 ± 11.65 vs. 20.99 ± 9.86 ng/mL, p=0.001). HT was observed 2.28 times more frequently in individuals with 25(OH)D3 levels <20 ng/mL (OR: 2.28, CI: 1.21-4.3).

CONCLUSION

Vitamin D deficiency is associated with HT in children and adolescents. Levels lower than 20 ng/mL seem to be critical. The mechanism for this association is not clear.

Vitamin D deficiency as a risk factor for infection, sepsis and mortality in the critically ill: systematic review and meta-analysis

Introduction

In Europe, vitamin D deficiency is highly prevalent varying between 40% and 60% in the healthy general adult population. The consequences of vitamin D deficiency for sepsis and outcome in critically ill patients remain controversial. We therefore systematically reviewed observational cohort studies on vitamin D deficiency in the intensive care unit.

Methods

Fourteen observational reports published from January 2000 to March 2014, retrieved from Pubmed and Embase, involving 9,715 critically ill patients and serum 25-hydroxyvitamin D₃ (25 (OH)-D) concentrations, were meta-analysed.

Results

Levels of 25 (OH)-D less than 50 nmol/L were associated with increased rates of infection (risk ratio (RR) 1.49, 95% (confidence interval (CI) 1.12 to 1.99), P = 0.007), sepsis (RR 1.46, 95% (CI 1.27 to 1.68), P <0.001), 30-day mortality (RR 1.42, 95% (CI 1.00 to 2.02), P = 0.05), and in-hospital mortality (RR 1.79, 95% (CI 1.49 to 2.16), P <0.001). In a subgroup analysis of adjusted data including vitamin D deficiency as a risk factor for 30-day mortality the pooled RR was 1.76 (95% CI 1.37 to 2.26, P <0.001).

Conclusions

This meta-analysis suggests that vitamin D deficiency increases susceptibility for severe infections and mortality of the critically ill.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0660-4) contains supplementary material, which is available to authorized users.

Vitamin D supplementation for prevention of cancer in adults

BACKGROUND

The evidence on whether vitamin D supplementation is effective in decreasing cancers is contradictory.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D supplementation for prevention of cancer in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, LILACS, Science Citation Index Expanded, and the Conference Proceedings Citation Index-Science to February 2014. We scanned bibliographies of relevant publications and asked experts and pharmaceutical companies for additional trials.

SELECTION CRITERIA

We included randomised trials that compared vitamin D at any dose, duration, and route of administration versus placebo or no intervention in adults who were healthy or were recruited among the general population, or diagnosed with a specific disease. Vitamin D could have been administered as supplemental vitamin D (vitamin D₃ (cholecalciferol) or vitamin D₂ (ergocalciferol)), or an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol), or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

Two review authors extracted data independently. We conducted random-effects and fixed-effect model meta-analyses. For dichotomous outcomes, we calculated the risk ratios (RRs). We considered risk of bias in order to assess the risk of systematic errors. We conducted trial sequential analyses to assess the risk of random errors.

MAIN RESULTS

Eighteen randomised trials with 50,623 participants provided data for the analyses. All trials came from high-income countries. Most of the trials had a high risk of bias, mainly for-profit bias. Most trials included elderly community-dwelling women (aged 47 to 97 years). Vitamin D was administered for a weighted mean of six years. Fourteen trials tested vitamin D₃, one trial tested vitamin D₂, and three trials tested calcitriol supplementation. Cancer occurrence was observed in 1927/25,275 (7.6%) recipients of vitamin D versus 1943/25,348 (7.7%) recipients of control interventions (RR 1.00 (95% confidence interval (CI) 0.94 to 1.06); P = 0.88; I² = 0%; 18 trials; 50,623 participants; moderate quality evidence according to the GRADE instrument). Trial sequential analysis (TSA) of the 18 vitamin D trials shows that the futility area is reached after the 10th trial, allowing us to conclude that a possible intervention effect, if any, is lower than a 5% relative risk reduction. We did not observe substantial differences in the effect of vitamin D on cancer in subgroup analyses of trials at low risk of bias compared to trials at high risk of bias; of trials with no risk of for-profit bias compared to trials with risk of for-profit bias; of trials assessing primary prevention compared to trials assessing secondary prevention; of trials including participants with vitamin D levels below 20 ng/mL at entry compared to trials including participants with vitamin D levels of 20 ng/mL or more at entry; or of trials using concomitant calcium supplementation compared to trials without calcium. Vitamin D decreased all-cause mortality (1854/24,846 (7.5%) versus 2007/25,020 (8.0%); RR 0.93 (95% CI 0.88 to 0.98); P = 0.009; I² = 0%; 15 trials; 49,866 participants; moderate quality evidence), but TSA indicates that this finding could be due to random errors. Cancer occurrence was observed in 1918/24,908 (7.7%) recipients of vitamin D₃ versus 1933/24,983 (7.7%) in recipients of control interventions (RR 1.00 (95% CI 0.94 to 1.06); P = 0.88; I² = 0%; 14 trials; 49,891 participants; moderate quality evidence). TSA of the vitamin D₃ trials shows that the futility area is reached after the 10th trial, allowing us to conclude that a possible intervention effect, if any, is lower than a 5% relative risk reduction. Vitamin D₃ decreased cancer mortality (558/22,286 (2.5%) versus 634/22,206 (2.8%); RR 0.88 (95% CI 0.78 to 0.98); P = 0.02; I² = 0%; 4 trials; 44,492 participants; low quality evidence), but TSA indicates that this finding could be due to random errors. Vitamin D₃ combined with calcium increased nephrolithiasis (RR 1.17 (95% CI 1.03 to 1.34); P = 0.02; I² = 0%; 3 trials; 42,753 participants; moderate quality evidence). TSA, however, indicates that this finding could be due to random errors. We did not find any data on health-related quality of life or health economics in the randomised trials included in this review.

AUTHORS' CONCLUSIONS

There is currently no firm evidence that vitamin D supplementation decreases or increases cancer occurrence in predominantly elderly community-dwelling women. Vitamin D₃ supplementation decreased cancer mortality and vitamin D supplementation decreased all-cause mortality, but these estimates are at risk of type I errors due to the fact that too few participants were examined, and to risks of attrition bias originating from substantial dropout of participants. Combined vitamin D₃ and calcium supplements increased nephrolithiasis, whereas it remains unclear from the included trials whether vitamin D₃, calcium, or both were responsible for this effect. We need more trials on vitamin D supplementation, assessing the benefits and harms among younger participants, men, and people with low vitamin D status, and assessing longer duration of treatments as well as higher dosages of vitamin D. Follow-up of all participants is necessary to reduce attrition bias.

Immunostimulation in the treatment for chronic fatigue syndrome/myalgic encephalomyelitis

Chronic fatigue syndrome (CFS)/myalgic encephalomyelitis (ME) has long been associated with the presence of infectious agents, but no single pathogen has been reliably identified in all patients with the disease. Recent studies using metagenomic techniques have demonstrated the presence of thousands of microbes in the human body that were previously undetected and unknown to science. More importantly, such species interact together by sharing genes and genetic function within communities. It follows that searching for a singular pathogen may greatly underestimate the microbial complexity potentially driving a complex disease like CFS/ME. Intracellular microbes alter the expression of human genes in order to facilitate their survival. We have put forth a model describing how multiple species-bacterial, viral, and fungal-can cumulatively dysregulate expression by the VDR nuclear receptor in order to survive and thus drive a disease process. Based on this model, we have developed an immunostimulatory therapy that is showing promise inducing both subjective and objective improvement in patients suffering from CFS/ME.

Vitamin D supplementation for prevention of mortality in adults

BACKGROUND

Available evidence on the effects of vitamin D on mortality has been inconclusive. In a recent systematic review, we found evidence that vitamin D3 may decrease mortality in mostly elderly women. The present systematic review updates and reassesses the benefits and harms of vitamin D supplementation used in primary and secondary prophylaxis of mortality.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D supplementation for prevention of mortality in healthy adults and adults in a stable phase of disease.

SEARCH METHODS

We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index-Expanded and Conference Proceedings Citation Index-Science (all up to February 2012). We checked references of included trials and pharmaceutical companies for unidentified relevant trials.

SELECTION CRITERIA

Randomised trials that compared any type of vitamin D in any dose with any duration and route of administration versus placebo or no intervention in adult participants. Participants could have been recruited from the general population or from patients diagnosed with a disease in a stable phase. Vitamin D could have been administered as supplemental vitamin D (vitamin D3 (cholecalciferol) or vitamin D2 (ergocalciferol)) or as an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol) or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

Six review authors extracted data independently. Random-effects and fixed-effect meta-analyses were conducted. For dichotomous outcomes, we calculated the risk ratios (RRs). To account for trials with zero events, we performed meta-analyses of dichotomous data using risk differences (RDs) and empirical continuity corrections. We used published data and data obtained by contacting trial authors.To minimise the risk of systematic error, we assessed the risk of bias of the included trials. Trial sequential analyses controlled the risk of random errors possibly caused by cumulative meta-analyses.

MAIN RESULTS

We identified 159 randomised clinical trials. Ninety-four trials reported no mortality, and nine trials reported mortality but did not report in which intervention group the mortality occurred. Accordingly, 56 randomised trials with 95,286 participants provided usable data on mortality. The age of participants ranged from 18 to 107 years. Most trials included women older than 70 years. The mean proportion of women was 77%. Forty-eight of the trials randomly assigned 94,491 healthy participants. Of these, four trials included healthy volunteers, nine trials included postmenopausal women and 35 trials included older people living on their own or in institutional care. The remaining eight trials randomly assigned 795 participants with neurological, cardiovascular, respiratory or rheumatoid diseases. Vitamin D was administered for a weighted mean of 4.4 years. More than half of the trials had a low risk of bias. All trials were conducted in high-income countries. Forty-five trials (80%) reported the baseline vitamin D status of participants based on serum 25-hydroxyvitamin D levels. Participants in 19 trials had vitamin D adequacy (at or above 20 ng/mL). Participants in the remaining 26 trials had vitamin D insufficiency (less than 20 ng/mL).Vitamin D decreased mortality in all 56 trials analysed together (5,920/47,472 (12.5%) vs 6,077/47,814 (12.7%); RR 0.97 (95% confidence interval (CI) 0.94 to 0.99); P = 0.02; I(2) = 0%). More than 8% of participants dropped out. 'Worst-best case' and 'best-worst case' scenario analyses demonstrated that vitamin D could be associated with a dramatic increase or decrease in mortality. When different forms of vitamin D were assessed in separate analyses, only vitamin D3 decreased mortality (4,153/37,817 (11.0%) vs 4,340/38,110 (11.4%); RR 0.94 (95% CI 0.91 to 0.98); P = 0.002; I(2) = 0%; 75,927 participants; 38 trials). Vitamin D2, alfacalcidol and calcitriol did not significantly affect mortality. A subgroup analysis of trials at high risk of bias suggested that vitamin D2 may even increase mortality, but this finding could be due to random errors. Trial sequential analysis supported our finding regarding vitamin D3, with the cumulative Z-score breaking the trial sequential monitoring boundary for benefit, corresponding to 150 people treated over five years to prevent one additional death. We did not observe any statistically significant differences in the effect of vitamin D on mortality in subgroup analyses of trials at low risk of bias compared with trials at high risk of bias; of trials using placebo compared with trials using no intervention in the control group; of trials with no risk of industry bias compared with trials with risk of industry bias; of trials assessing primary prevention compared with trials assessing secondary prevention; of trials including participants with vitamin D level below 20 ng/mL at entry compared with trials including participants with vitamin D levels equal to or greater than 20 ng/mL at entry; of trials including ambulatory participants compared with trials including institutionalised participants; of trials using concomitant calcium supplementation compared with trials without calcium; of trials using a dose below 800 IU per day compared with trials using doses above 800 IU per day; and of trials including only women compared with trials including both sexes or only men. Vitamin D3 statistically significantly decreased cancer mortality (RR 0.88 (95% CI 0.78 to 0.98); P = 0.02; I(2) = 0%; 44,492 participants; 4 trials). Vitamin D3 combined with calcium increased the risk of nephrolithiasis (RR 1.17 (95% CI 1.02 to 1.34); P = 0.02; I(2) = 0%; 42,876 participants; 4 trials). Alfacalcidol and calcitriol increased the risk of hypercalcaemia (RR 3.18 (95% CI 1.17 to 8.68); P = 0.02; I(2) = 17%; 710 participants; 3 trials).

AUTHORS' CONCLUSIONS

Vitamin D3 seemed to decrease mortality in elderly people living independently or in institutional care. Vitamin D2, alfacalcidol and calcitriol had no statistically significant beneficial effects on mortality. Vitamin D3 combined with calcium increased nephrolithiasis. Both alfacalcidol and calcitriol increased hypercalcaemia. Because of risks of attrition bias originating from substantial dropout of participants and of outcome reporting bias due to a number of trials not reporting on mortality, as well as a number of other weaknesses in our evidence, further placebo-controlled randomised trials seem warranted.

Helicobacter pylori infection is associated with the presence of thyroid nodules in the euthyroid population

Helicobacter pylori infection is associated with extragastric diseases. The thyroid may be one of the targets of chronic inflammation. Here, we sought to investigate whether H. pylori infections were associated with the presence of thyroid nodules. A total of 988 euthyroid subjects from China were included in this cross-sectional study. Four hundred thirty-five (44.0%) subjects were diagnosed as having thyroid nodules, and 486 (49.2%) were diagnosed with H. pylori infections. The thyroid nodules group had a higher proportion of H. pylori infections than the control group (P = 0.002). Free thyroxine (FT4) levels were lower and the prevalence of thyroid nodules was higher in patients with H. pylori infection compared to those without infection, even after adjustment for age, gender, and body mass index (BMI; all P < 0.05). The prevalence of H. pylori infection showed a decreasing trend as serum FT4 level increased (P_trend = 0.020). Stepwise logistic regression analysis showed that H. pylori infection was significantly associated with the risk of thyroid nodules (odds ratio: 1.390, 95% confidence interval: 1.059–1.824, P = 0.018). Our results suggested that H. pylori infections were positively associated with the presence of thyroid nodules in the euthyroid population, whose thyroid functions were in the reference range.

MNU-induced mammary gland carcinogenesis: chemopreventive and therapeutic effects of vitamin D and Seocalcitol on selected regulatory vitamin D receptor pathways

The effects of administration of vitamin D₃ and Seocalcitol on MNU-induced carcinogenesis of mammary gland in Sprague-Dawley rats have been investigated. Administration of both substances in a weekly dose of 7 μg/kg caused prolonged latency of mammary gland tumors. The latency of tumors was markedly prolonged for 30-40 days by Seocalcitol. Using PET analysis, reduction in [¹⁸F]2-fluoro-2-deoxy-d-glucose (FDG) uptake or tumor volume in tumors chemopreventively treated with vitamin D₃ were detected in MNU-induced tumors, vitamin D₃ reduced expression of 25-hydroxylase (25OHase) (p<0.01) and 24-hydroxylase (24OHase) (p<0.01) and Seocalcitol 24OHase. Positive regulation of 25OHase mRNA level after the treatment with vitamin D₃ was observed in liver, while in kidney, vitamin D₃ and Seocalcitol induced expression of 24OHase was significant. Our observations indicate a cross talk between respective pathways of VDR, RARs/RXRs, TRs and ERs in carcinogenesis process.

Vitamin D supplementation for prevention of mortality in adults

BACKGROUND

The available evidence on vitamin D and mortality is inconclusive.

OBJECTIVES

To assess the beneficial and harmful effects of vitamin D for prevention of mortality in adults.

SEARCH STRATEGY

We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index Expanded, and Conference Proceedings Citation Index-Science (to January 2011). We scanned bibliographies of relevant publications and asked experts and pharmaceutical companies for additional trials.

SELECTION CRITERIA

We included randomised trials that compared vitamin D at any dose, duration, and route of administration versus placebo or no intervention. Vitamin D could have been administered as supplemental vitamin D (vitamin D(3) (cholecalciferol) or vitamin D(2) (ergocalciferol)) or an active form of vitamin D (1α-hydroxyvitamin D (alfacalcidol) or 1,25-dihydroxyvitamin D (calcitriol)).

DATA COLLECTION AND ANALYSIS

Six authors extracted data independently. Random-effects and fixed-effect model meta-analyses were conducted. For dichotomous outcomes, we calculated the risk ratios (RR). To account for trials with zero events, meta-analyses of dichotomous data were repeated using risk differences (RD) and empirical continuity corrections. Risk of bias was considered in order to minimise risk of systematic errors. Trial sequential analyses were conducted to minimise the risk of random errors.

MAIN RESULTS

Fifty randomised trials with 94,148 participants provided data for the mortality analyses. Most trials included elderly women (older than 70 years). Vitamin D was administered for a median of two years. More than one half of the trials had a low risk of bias. Overall, vitamin D decreased mortality (RR 0.97, 95% confidence interval (CI) 0.94 to 1.00, I(2) = 0%). When the different forms of vitamin D were assessed separately, only vitamin D(3) decreased mortality significantly (RR 0.94, 95% CI 0.91 to 0.98, I(2) = 0%; 74,789 participants, 32 trials) whereas vitamin D(2), alfacalcidol, or calcitriol did not. Trial sequential analysis supported our finding regarding vitamin D(3), corresponding to 161 individuals treated to prevent one additional death. Vitamin D(3) combined with calcium increased the risk of nephrolithiasis (RR 1.17, 95% CI 1.02 to 1.34, I(2) = 0%). Alfacalcidol and calcitriol increased the risk of hypercalcaemia (RR 3.18, 95% CI 1.17 to 8.68, I(2) = 17%). Data on health-related quality of life and health economics were inconclusive.

AUTHORS' CONCLUSIONS

Vitamin D in the form of vitamin D(3) seems to decrease mortality in predominantly elderly women who are mainly in institutions and dependent care. Vitamin D(2), alfacalcidol, and calcitriol had no statistically significant effect on mortality. Vitamin D(3) combined with calcium significantly increased nephrolithiasis. Both alfacalcidol and calcitriol significantly increased hypercalcaemia.

Immunostimulation in the era of the metagenome

Microbes are increasingly being implicated in autoimmune disease. This calls for a re-evaluation of how these chronic inflammatory illnesses are routinely treated. The standard of care for autoimmune disease remains the use of medications that slow the immune response, while treatments aimed at eradicating microbes seek the exact opposite-stimulation of the innate immune response. Immunostimulation is complicated by a cascade of sequelae, including exacerbated inflammation, which occurs in response to microbial death. Over the past 8 years, we have collaborated with American and international clinical professionals to research a model-based treatment for inflammatory disease. This intervention, designed to stimulate the innate immune response, has required a reevaluation of disease progression and amelioration. Paramount is the inherent conflict between palliation and microbicidal efficacy. Increased microbicidal activity was experienced as immunopathology-a temporary worsening of symptoms. Further studies are needed, but they will require careful planning to manage this immunopathology.

Role of gender in multiple sclerosis: clinical effects and potential molecular mechanisms

Multiple sclerosis (MS) is more prevalent in females than males, and this female predominance is increasing as time goes by. Additionally, gender appears to play critical roles in development, progression and treatment of MS, and is therefore an aspect that should always be considered in the design and interpretation of research and clinical trials for MS. In this review, factors that could potentially explain the gender-biased observations in MS are discussed. These include sex-specific differences between the male and female immune systems and nervous systems, genetic and epigenetic or environmental-related effects, the effects of gonadal hormones, and materno-fetal interactions.

Calcium and vitamin D in sarcoidosis: how to assess and manage

The synthesis of vitamin D is altered by the granulomatous inflammation of sarcoidosis leading to increased production of 1, 25-dihydroxyvitamin D. Mounting evidence suggests that vitamin D is an immunomodulating hormone that inhibits both antigen presentation by cells of the innate immune system, and the cytokine release and proliferation of Th1 cells. These and other extraskeletal health benefits have led to an increase in vitamin D assessment and pharmacological supplementation in the general population. This review highlights the altered synthesis and general immunomodulating properties of vitamin D with a special emphasis on known interactions with sarcoidosis. In addition, the assessment of vitamin D nutritional status, its pharmacological supplementation, and the management of bone health in patients with sarcoidosis are reviewed.

Reversing bacteria-induced vitamin D receptor dysfunction is key to autoimmune disease

Vitamin D research is discussed in light of the hypothesis that the lower average levels of vitamin D frequently observed in autoimmune disease are not a sign of deficiency. Instead, it is proposed that the lower levels result from chronic infection with intracellular bacteria that dysregulate vitamin D metabolism by causing vitamin D receptor (VDR) dysfunction within phagocytes. The VDR dysfunction causes a decline in innate immune function that causes susceptibility to additional infections that contribute to disease progression. Evidence has been accumulating that indicates that a number of autoimmune diseases can be reversed by gradually restoring VDR function with the VDR agonist olmesartan and subinhibitory dosages of certain bacteriostatic antibiotics. Diseases showing favorable responses to treatment so far include systemic lupus erythematosis, rheumatoid arthritis, scleroderma, sarcoidosis, Sjogren's syndrome, autoimmune thyroid disease, psoriasis, ankylosing spondylitis, Reiter's syndrome, type I and II diabetes mellitus, and uveitis. Disease reversal using this approach requires limitation of vitamin D in order to avoid contributing to dysfunction of nuclear receptors and subsequent negative consequences for immune and endocrine function. Immunopathological reactions accompanying bacterial cell death require a gradual elimination of pathogens over several years. Practical and theoretical implications are discussed, along with the compatibility of this model with current research.

Vitamin D metabolites as clinical markers in autoimmune and chronic disease

Recent research has implicated vitamin D deficiency (serum levels of 25-hydroxyvitamin D <50 nmol/L) with a number of chronic conditions, including autoimmune conditions such as multiple sclerosis, lupus, and psoriasis, and chronic conditions such as osteoporosis, osteoarthritis, metabolic syndrome, fibromyalgia and chronic fatigue syndrome. It has been assumed that low levels of 25-hydroxyvitamin D (25-D) accurately indicate vitamin D storage and vitamin D receptor (VDR)-mediated control of calcium metabolism and innate immunity. To evaluate this assumption, 25-D and 1,25-dihydroxyvitamin D3 (1,25-D) levels were measured in 100 Canadian patients with these conditions. Additionally, other inflammatory markers (CK, CRP) were measured. Results showed a strong positive association between these autoimmune conditions and levels of 1,25-D >110 pmol/L. However, there was little association with vitamin D deficiency or the other inflammatory markers, meaning that the results challenge the assumption that serum levels of 25-D are a sensitive measure of the autoimmune disease state. Rather, these findings support the use of 1,25-D as a clinical marker in autoimmune conditions. High levels of 1,25-D may result when dysregulation of the VDR by bacterial ligands prevents the receptor from expressing enzymes necessary to keep 1,25-D in a normal range.

Vitamin D: the alternative hypothesis

Early studies on vitamin D showed promise that various forms of the "vitamin" may be protective against chronic disease, yet systematic reviews and longer-term studies have failed to confirm these findings. A number of studies have suggested that patients with autoimmune diagnoses are deficient in 25-hydroxyvitamin D (25-D) and that consuming greater quantities of vitamin D, which further elevates 25 D levels, alleviates autoimmune disease symptoms. Some years ago, molecular biology identified 25 D as a secosteroid. Secosteroids would typically be expected to depress inflammation, which is in line with the reports of symptomatic improvement. The simplistic first-order mass-action model used to guide the early vitamin studies is now giving way to a more complex description of action. When active, the Vitamin D nuclear receptor (VDR) affects transcription of at least 913 genes and impacts processes ranging from calcium metabolism to expression of key antimicrobial peptides. Additionally, recent research on the Human Microbiome shows that bacteria are far more pervasive than previously thought, increasing the possibility that autoimmune disease is bacterial in origin. Emerging molecular evidence suggests that symptomatic improvements among those administered vitamin D is the result of 25-D's ability to temper bacterial-induced inflammation by slowing VDR activity. While this results in short-term palliation, persistent pathogens that may influence disease progression, proliferate over the long-term.

The relevance of vitamin D receptor gene polymorphisms for vitamin D research in multiple sclerosis

A poor vitamin D status has been associated with several autoimmune diseases, including multiple sclerosis (MS). The receptor for the biologically active metabolite of vitamin D appears to be a key player in these associations, not only as a mediator of the biological effects of vitamin D, but also as a mediator of the regulation of vitamin D metabolism itself. In this concise review, we will discuss the mostly investigated genetic polymorphisms of the vitamin D receptor (VDR), and their consequences for VDR functionality and immune regulation. Next, we will discuss the association of these polymorphisms with MS, and their relation with vitamin D metabolism. We conclude that polymorphisms of the VDR have major effects on vitamin D function and metabolism, and should therefore be assessed in studies on vitamin D and MS.

The paradoxical effects of vitamin D on type 1 mediated immunity

Low vitamin D status is associated with an increased risk of Th1 mediated autoimmune diseases like inflammatory bowel disease. 1,25(OH)(2)D(3) treatments have been shown to suppress Th1 mediated immunity and protect animals from experimental autoimmunity. Th1 mediated immunity is important for clearance of a number of different infectious diseases. For tuberculosis 1,25(OH)(2)D(3) treatment is associated with decreased Th1 mediated immunity but increased bactericidal activity. Systemic candidiasis is unaffected by 1,25(OH)(2)D(3) treatment. The seemingly paradoxical effects of 1,25(OH)(2)D(3) and vitamin D on Th1 mediated autoimmunity versus infectious immunity point to a broad array of vitamin D targets in the immune system. The interplay of these vitamin D targets and their impact on the host-immune response then dictate the outcome.