Mechanisms Underlying the Regulation of Innate and Adaptive Immunity by Vitamin D

Calcitriol alleviates noise-induced hearing loss by regulating the ATF3/DUSP1 signalling pathway

BACKGROUND

Calcitriol (Cal) is the most active metabolite of vitamin D and has antioxidant and anti-inflammatory properties. The aim of this study was to investigate the role of Cal in noise-induced hearing loss (NIHL) to further elucidate the mechanism of noise-induced oxidative stress in the mouse cochlea.

METHODS

C57BL/6 J mice were given six intraperitoneal injections of Cal (500 ng/kg/d). After 14 days of noise exposure, auditory brainstem response (ABR) thresholds, and the cochlear outer hair cell loss rate were analysed to evaluate auditory function. Real-time fluorescence quantitative PCR, immunofluorescence and western blotting were performed in vitro after the treatment of cochlear explants with 100 µM tert-butyl hydroperoxide (TBHP) for 2.5 h and HEI-OC1 cells with 250 µM TBHP for 1.5 h.

RESULTS

In vivo experiments confirmed that Cal pretreatment mitigated NIHL and outer hair cell death. The in vitro results demonstrated that Cal significantly reduced TBHP-induced cochlear auditory nerve fibre degradation and spiral ganglion neuron damage. Moreover, treatment with Cal inhibited the expression of oxidative stress-related factors (3-NT and 4-HNE) and DNA damage-related factors (γ-H2A.X) and attenuated TBHP-induced apoptosis in cochlear explants and HEI-OC1 cells. A total of 1479 upregulated genes and 1443 downregulated genes were screened in cochlear tissue 1 h after noise exposure. The level of transcription factor 3 (ATF3) was significantly elevated in HEI-OC1 cells after TBHP stimulation. Gene Transcription Regulation Database （GTRD）and Cistrome database analyses revealed that the downstream target gene of ATF3 is dual specificity phosphatase 1 (DUSP1). Cistrome DB Toolkit database results showed that the transcription factor of DUSP1 was ATF3. In addition, the ChIP-PCR results indicated that ATF3 might be a direct transcription factor of DUSP1.

CONCLUSION

The results of our study suggest that Cal attenuates NIHL and inhibits noise-induced apoptosis by regulating the ATF3/DUSP1 signalling pathway.

Association between serum 25-hydroxyvitamin D and asthma: Evidence from the National Health and Nutrition Examination Survey (NHANES) 2011-2018

BACKGROUND AND OBJECTIVE

Asthma is a heterogeneous respiratory disease characterized by airway hyper-responsiveness and reversible airflow blockage. There is ongoing debate about the impact of vitamin D on asthma. This research is focused on investigating the correlation between serum levels of 25-hydroxyvitamin D and asthma.

METHODS

This cross-sectional study comprised 22,708 eligible participants. Data on asthma and serum 25-hydroxyvitamin D levels from the National Health and Nutrition Examination Survey (NHANES) 2011-2018 were analyzed. Serum 25-hydroxyvitamin D levels were the main factor, with the presence of asthma as the outcome variable. Weighted logistic regression was utilized to investigate the relationship between serum levels of 25-hydroxyvitamin D and asthma, while accounting for factors such as age, gender, race, length of time in US, annual family income, education level, high-density lipoprotein, low-density lipoprotein, triglycerides, and cholesterol.

RESULTS

Upon adjusting all variables in model III, epi-25-hydroxyvitamin D3 displayed a negative correlation with current asthma at the lower quartile Q1 (0.784, [0.697 to 0.922]), Q2 (0.841, [0.729 to 0.946]), Q3 (0.396, [0.240 to 0.653]) when compared to the highest quartile Q4 level. However, no significant difference was observed between asthma and 25-hydroxyvitamin D2, as well as 25-hydroxyvitamin D3.

CONCLUSIONS

In the U.S. population, elevated levels of epi-25-hydroxyvitamin D3 are correlated with an increased risk of developing existing asthma. However, it is important to interpret this finding carefully given the constraints of cross-sectional studies.

The relationship between serum vitamin D, testosterone, and oxidative stress levels in women with sexual dysfunction: A case-controlled study

OBJECTIVE

Female sexual dysfunction (FSD) is highly prevalent and can result from hypovitaminosis D. Besides the role of vitamin D in normal bone development, studies showed it could reduce oxidative stress and lipid peroxidation. This prospective study aims to evaluate the relationship between serum vitamin D, testosterone, and oxidative stress levels in women with FSD.

MATERIALS AND METHODS

In this cross-sectional study, a total of 40 women with FSD (age range: 18-45 years) were randomly assigned into two groups of intervention and control. In the intervention group, patients received vitamin D 300,000 IU intramuscularly (IM) and then 50,000 IU orally once a week for four weeks. We measured the serum vitamin D, testosterone, and oxidative stress levels, as well as the Female Sexual Function Index (FSFI) at baseline and monthly for three months.

RESULTS

Serum testosterone levels significantly increased in the intervention group at the end of the third month (P = 0.014). Also, FSFI scores significantly improved (P < 0.01) in the intervention group compared to the control group. While there was positive a correlation between serum vitamin D levels with glutathione, total antioxidant capacity (TAC), testosterone, and FSFI score, there was a negative correlation between serum vitamin D levels with malondialdehyde (MDA), protein carbonyl, and nitric oxide.

CONCLUSION

We witnessed that women with FSD had low serum vitamin D levels. So, modifying serum vitamin D levels must be considered as a treatment option. Moreover, vitamin D supplementation improved testosterone, serum oxidative stress, and sexual function.

Relation of T Cell Profile with Vitamin D Receptor and Vitamin D-Binding Protein Gene Polymorphisms in Atopy

Atopic diseases, including atopic dermatitis (AD) and allergic asthma (AA), are characterized by complex immune responses involving various T cells subsets and their cytokine profiles. It is assumed that single nucleotide polymorphisms (SNPs) in the Vitamin D receptor (VDR) gene and the Vitamin D-binding protein (GC) gene are related to the action of Vitamin D and, consequently, play a role in regulating the immune response. However, there is not enough data to unequivocally support the hypothesis about the relationship between T cells profile and VDR or GC SNPs. Two hundred sixty-six subjects (aged > 18 years) were involved in the study: 100 patients with mild or moderate AD, 85 patients with mild or moderate AA, and 81 healthy individuals. Blood cell counts were determined by standard methods. Flow cytometric analysis was used to evaluate CD4+ T-helper (Th) cell subtypes: Th2, Th1, Th17, and T regulatory (Treg) cells in peripheral blood. Measurements of cytokines, total immunoglobulin E (IgE), and Vitamin D levels in serum were evaluated by ELISA. Significantly higher levels of Th1, Th2, and Th17 cells, along with lower levels of Tregs, were found in patients with atopic diseases compared to healthy individuals. Additionally, higher serum levels of interleukin (IL) 5, IL-17A, and transforming growth factor-β1 (TGF-β1), as well as lower levels of IL-10, were observed in patients with atopic diseases than in control. The study established associations between VDR SNPs and immune profiles: the AA genotype of rs731236 was associated with increased Th2 and Th17 cells and a higher Th1/Th2 ratio; the GG genotype of rs731236 was linked to decreased serum IL-10 and TGF-β1 levels; and the TT genotype of rs11168293 was associated with increased IL-10 levels. Additionally, the GG genotype of GC gene SNP rs4588 was associated with reduced Th2 and Th17 lymphocytes, while the TT genotype of rs4588 was linked to decreased IL-10 levels. Furthermore, the CC genotype of rs7041 was associated with higher levels of Th2, Th17, IL-10, and IL-35, as well as reduced levels of TGF-β1, while the GG genotype of rs3733359 was associated with reduced IL-10 levels. In conclusion, our study demonstrates that the Vitamin D receptor gene single nucleotide polymorphisms rs731236 and rs11168293, along with polymorphisms in the Vitamin D-binding protein gene (rs4588, rs7041, rs3733359), are significantly associated with variations in T cell profiles in atopy. These variations may play a crucial role in promoting inflammation and provide insight into the genetic factors contributing to the pathogenesis of atopy.

Vitamin D in Central Nervous System: Implications for Neurological Disorders

Vitamin D, obtained from diet or synthesized internally as cholecalciferol and ergocalciferol, influences bodily functions through its most active metabolite and the vitamin D receptor. Recent research has uncovered multiple roles for vitamin D in the central nervous system, impacting neural development and maturation, regulating the dopaminergic system, and controlling the synthesis of neural growth factors. This review thoroughly examines these connections and investigates the consequences of vitamin D deficiency in neurological disorders, particularly neurodegenerative diseases. The potential benefits of vitamin D supplementation in alleviating symptoms of these diseases are evaluated alongside a discussion of the controversial findings from previous intervention studies. The importance of interpreting these results cautiously is emphasised. Furthermore, the article proposes that additional randomised and well-designed trials are essential for gaining a deeper understanding of the potential therapeutic advantages of vitamin D supplementation for neurological disorders. Ultimately, this review highlights the critical role of vitamin D in neurological well-being and highlights the need for further research to enhance our understanding of its function in the brain.

Calcifediol boosts efficacy of ChAdOx1 nCoV-19 vaccine by upregulating genes promoting memory T cell responses

The ChAdOx1 nCoV-19 (COVISHIELD) vaccine has emerged as a pivotal tool in the global fight against the COVID-19 pandemic. In our previous study eligible subjects were supplemented with calcifediol, a direct precursor to the biologically active form of vitamin D, calcitriol with an objective to enhance the immunogenicity of the COVISHIELD vaccine. Herein we investigated the effects of calcifediol supplementation on gene expression profiles in individuals who received the COVISHIELD vaccine. Peripheral blood mononuclear cells were isolated from vaccinated individuals with and without calcifediol supplementation at baseline, 3rd and 6th month, and the gene expression profiles were analyzed using high-throughput sequencing. The results revealed distinct patterns of gene expression associated with calcifediol supplementation, suggesting potential molecular mechanisms underlying the beneficial effects of calcifediol in improving the efficacy of COVISHIELD vaccine via augmentation of T cell activation, proliferation and T cell memory responses. Additionally, there was upregulation of NOD like receptor, JAK/STAT and TGF beta signaling pathways. Calcifediol supplementation in vaccinated individuals also downregulated the pathways related to the Coronavirus disease. Taken together, our findings provide valuable insights into the interplay between vitamin D receptor (VDR) signaling and vaccine-induced immune responses and offer another approach in improving vaccination induced antiviral responses.

Associations of Serum Vitamin D With Dental Caries and Periodontitis: The HUNT Study

OBJECTIVE

To study the relationships of serum 25-hydroxyvitamin D [25(OH)D] with dental caries and periodontitis in a general Norwegian adult population.

METHODS

We analysed a subsample of 1605 participants from the Trøndelag Health Study (HUNT) in Norway that had serum 25(OH)D levels measured in HUNT3 (2006-08) and oral health assessed in the HUNT4 Oral Health Study (2017-19). Negative binomial and Poisson regression models were used to estimate the ratios of means (RMs; for count oral outcomes) and prevalence ratios (PRs; for dichotomous oral outcomes).

RESULTS

Serum 25(OH)D was inversely associated with the number of decayed teeth in a dose-response gradient (<30.0 nmol/L: RM 1.41, 95% CI 1.07-1.85; 30.0-49.9 nmol/L: 1.14, 0.98-1.32 and ≥75.0 nmol/L: 0.84, 0.67-1.04, as compared to the 50.0-74.9 nmol/L group, P for trend <.001). Each 25 nmol/L decrease in 25(OH)D level was associated with a 15% (RM 1.15, 95% CI 1.05-1.26) increase in the mean number of decayed teeth. Serum 25(OH)D <30.0 nmol/L was associated with a 35% higher prevalence of severe periodontitis (PR 1.35, 95% CI 1.00-1.83). No association was observed between 25(OH)D and the number of natural teeth.

CONCLUSION

The present study suggested that serum 25(OH)D level had an inverse and dose-response association with the number of decayed teeth, and serum 25(OH)D <30 nmol/L was associated with a higher prevalence of severe periodontitis in this Norwegian adult population.

Elevated serum 25-hydroxyvitamin D: a potential indicator of remission in Takayasu arteritis patients with normal ESR and CRP levels

OBJECTIVE

The goal of the present study was to investigate the correlation between serum 25-hydroxyvitamin D [25(OH)D] levels and disease remission in Takayasu arteritis (TAK) patients.

METHODS

This retrospective study included 59 patients in the study group and 80 patients in the validation cohort with TAK. After 6 months of therapy, patients were re-evaluated, and serum 25(OH)D levels were compared before and after treatment. Correlations between changes in 25(OH)D levels and changes in disease activity scores (NIH, ITAS2010, ITAS.A) were analyzed. Additionally, a predictive cut-off value for disease remission was determined.

RESULTS

After 6 months of therapy, serum 25(OH)D levels in TAK patients significantly increased compared to baseline [(18.33 ± 7.25)µg/L vs (11.77 ± 4.14) µg/L] (P < 0.001). Positive correlations were observed between the increasing changes in the 25(OH)D level and the decreasing changes in the reduced NIH, ITAS2010, and ITAS.A scores (r = 0.455, P < 0.001; r = 0.495, P < 0.001; and r = 0.352 P = 0.006, respectively). A change of 8.45 µg/L in 25(OH)D level was identified as the predictive cut-off value for TAK remission (sensitivity 54.1%, specificity 90.9%, area under the curve = 0.741). Similarly for patients with normal baseline ESR, sensitivity is 68.0%, specificity is 92.3%, and area under the curve is 0.831, and for patients with normal baseline CRP, sensitivity is 58.3%, specificity is 90.0%, and area under the curve is 0.748. Validation in an additional 80 patients demonstrated a higher remission rate in those with a 25(OH)D level change > 8.45 µg/L.

CONCLUSION

Serum 25(OH)D levels significantly increased after treatment in TAK patients, and an increase of ≥ 8.45 µg/L was predictive of disease remission, especially in individuals with normal baseline ESR and/or CRP levels. Key Points • Following treatment, there was a significant increase in serum 25(OH)D levels among TAK patients. • The elevated changes in 25(OH)D levels before and after treatment demonstrated a positive correlation with the reduction in disease activity scores. • In patients with TAK before and after treatment, an elevation in serum 25(OH)D levels exceeding 8.45 µg/L serves as an indicator for disease remission, particularly prominent in individuals with normal baseline ESR and/or CRP levels.

Relationship between human papillomavirus and serum vitamin D levels: a systematic review

BACKGROUND

Human papillomavirus (HPV) is one of the most prevalent sexually transmitted diseases worldwide. The present review was conducted to accumulate evidence on the relationship between cervicovaginal human papillomavirus infection and serum vitamin D status.

METHODS

Electronic databases including Web of Science, Embase, Scopus, and PubMed were searched by different combinations of keywords related to "human papillomavirus" and "vitamin D", obtained from Mesh and Emtree with AND, and OR operators without any time restriction until December 24, 2022. Selection of articles was based on the inclusion and exclusion criteria. Newcastle-Ottawa Scale was used for quality assessment. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist was applied for reporting.

RESULTS

In total, 276 citations were retrieved. After removing duplicates, and non-related articles, the full texts of 7 articles were reviewed including 11168 participants. Three studies reported that there was a positive relationship between vitamin D deficiency and cervicovaginal human papillomavirus while three studies did not. One study showed a significant positive association between higher vitamin D stores and short-term high-risk human papillomavirus persistence.

CONCLUSIONS

The findings showed no firm evidence for any association between serum vitamin D level and cervicovaginal human papillomavirus infection, although the possible association could not be discarded. Further investigations are needed to reach sound evidence.

The Associations of Vitamin D with Ovarian Reserve Markers and Depression: A Narrative Literature Review

Since the identification of vitamin D receptors in both the female reproductive tract and the central nervous system, further data have shown that vitamin D is involved in the processes of reproductive and mental health. This paper reviews current research on the associations of vitamin D with ovarian reserve markers and depression and discusses the potential role of vitamin D in their relationships. There have been numerous studies reporting that vitamin D was significantly related to ovarian reserve markers and depression in basic or clinical research, but some observational and interventional clinical studies have shown inconsistent results. Nevertheless, recent meta-analyses of interventional studies have provided promising results showing that vitamin D supplementation significantly improves ovarian reserve metrics, especially in a subgroup of women with normal or diminished ovarian reserve, and decreases depressive symptoms and risk. The demonstration of an association of vitamin D with both ovarian reserve and depression could suggest that vitamin D may be another important key in explaining female reproductive depression. Larger-scale studies in standardized settings will be needed in order to gain further insight into the role of vitamin D in female reproduction and depression.

CYP27B1 Enzyme in Psoriasis: A Preliminary Study of Immunohistochemical Observations

Connections between vitamin D and psoriasis have been a matter of interest for the past decades, with its active metabolite, 1,25(OH)2 vitamin D, being valued for antiproliferative and immunomodulatory effects. However, none of vitamin D's actions could be possible without the CYP27B1 enzyme that bio-activates this metabolite of interest. In order to see if there is any link between the enzyme expression and the disease's particularities, we conducted a preliminary study that involved 11 skin biopsies of patients with mild (n = 4) or moderate to severe psoriasis (n = 7). The cell proliferation antigen Ki67 and the CD45RO+ marker were also assessed. Compared with healthy skin, in psoriasis, it is reported that the enzyme's expression seems to be more ubiquitous, but a clear correlation between the disease's severity and the CYP27B1 expression was, to our knowledge, lacking. We found that, in patients with very mild psoriasis, the enzyme expression was observed in the epidermal stratum basale in a similar manner as in healthy skin specimens. Contrary, for higher severity scores, a divergent result was observed, with the enzyme being either variably spread in the epidermal stratum spinosum or completely absent. Unlike malignant diseases, a significant connection between CYP27B1 and Ki67 (p = 0.313) or CYP27B1 and CD45RO+ (p = 0.657) does not seem to be relevant in psoriasis.

Vitamin A, D, E, and K as Matrix Metalloproteinase-2/9 Regulators That Affect Expression and Enzymatic Activity

Fat-soluble vitamins (vitamin A, D, E, and K) assume a pivotal role in maintaining human homeostasis by virtue of their enzymatic functions. The daily inclusion of these vitamins is imperative to the upkeep of various physiological processes including vision, bone health, immunity, and protection against oxidative stress. Current research highlights fat-soluble vitamins as potential therapeutics for human diseases, especially cancer. Fat-soluble vitamins exert their therapeutic effects through multiple pathways, including regulation of matrix metalloproteinases' (MMPs) expression and enzymatic activity. As MMPs have been reported to be involved in the pathology of various diseases, such as cancers, cardiovascular diseases, and neurological disorders, regulating the expression and/or activity of MMPs could be considered as a potent therapeutic strategy. Here, we summarize the properties of fat-soluble vitamins and their potential as promising candidates capable of effectively modulating MMPs through multiple pathways to treat human diseases.

"You are my sunshine, my only sunshine": maternal vitamin D status and supplementation in pregnancy and their effect on neonatal and childhood outcomes

Vitamin D (VD) plays a crucial role in regulating calcium homeostasis, while the wealth of its pleiotropic actions is gaining increasing research interest. Sufficient VD concentrations are of clinical relevance, particularly in the context of physiological alterations, such as those occurring during pregnancy when maternal VD is the sole source for the developing fetus. As a result, inadequate VD concentrations in pregnancy have been associated with perinatal complications and adverse neonatal outcomes, including preeclampsia, gestational diabetes mellitus, increased rates of cesarean section, low birth weight, small-for-gestational-age infants, poor immune and skeletal growth, allergies, and respiratory infections. Over the past few decades, several observational studies have underlined the important role of maternal VD in the neural, musculoskeletal, and psychomotor growth and bone health of the offspring. However, the complexity of the factors involved in regulating and assessing VD homeostasis, including race, sun exposure, dietary habits, and laboratory measurement techniques, makes the interpretation of relevant research findings challenging. The aim of this narrative review is to summarize the evidence on the importance of VD in maintaining optimal health during pregnancy, infancy, childhood, and adolescence.

Vitamin D and Periodontal Health: A Systematic Review

The role of vitamin D in maintaining gum well-being is crucial. However, scientific research reported that the connotations of cholecalciferol and periodontal health have been divested in the present literature. However, there is enormous heterogeneity in the data available. The current review aims to systematically review and appraise the available literature investigating the role of vitamin D in maintaining periodontal health. Studies included randomized controlled trials and clinical trials following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and cohort studies reporting associations between vitamin D and oral health in systemically healthy patients. Databases such as PubMed, Google Scholar, Scopus, Embase, and other sources, including hand search, were searched until May 2023 using together-equipped search sequences. Altogether, scientific articles that conform to the inclusion principles underwent a thorough eminence evaluation. All papers meeting inclusion criteria were subject to quality assessment, and the method used to assess the risk of bias was the Cochrane risk of bias tool. The search identified 1883 papers, among which 1435 were excluded after title evaluation. After abstract and title screening, 455 were excluded, and six full texts were assessed. After full-text evaluation, two articles were excluded, and only four were included. The data shows vitamin D's association with oral health maintenance. Along with its action on bone metabolism, it has extended function, which provides for its action as an anti-inflammatory agent and production of anti-microbial peptides, which help maintain oral health. Although the literature available is immense, there is enormous heterogenicity in the papers conducted to appraise the association between vitamin D and oral health. This systematic review has filtered all the data to review a few essential aspects of the role of vitamin D in maintaining oral physiology. Vitamin D has a linear relationship with periodontal health; however, the evidence is insufficient, and further studies must be done.

The Sunlight-Vitamin D Connection: Implications for Patient Outcomes in the Surgical Intensive Care Unit

This review delves into the intricate relationship between Vitamin D and patient outcomes in the Surgical Intensive Care Unit (SICU). Vitamin D, known for its multifaceted roles in immune modulation, inflammation regulation, and maintenance of calcium homeostasis, emerges as a pivotal factor in the care of critically ill patients. Our exploration reveals a high prevalence of Vitamin D deficiency in the SICU, primarily attributable to limited sunlight exposure, comorbidities, and medication use. Importantly, Vitamin D status impacts infection rates, mortality, and length of stay in the SICU, making it a clinically relevant consideration. Mechanistic insights into the immunomodulatory and anti-inflammatory effects of Vitamin D shed light on its potential benefits in critical care. However, challenges, including accurate assessment, individualised supplementation, and ethical considerations regarding sunlight exposure, are evident. The prospect of personalised Vitamin D supplementation strategies offers promise for optimising patient care. In conclusion, the Sunlight-Vitamin D Connection holds significant potential to improve outcomes in the SICU, emphasising the importance of further research and tailored approaches for the well-being of critically ill individuals.

The Effect of Vit-D Supplementation on the Side Effect of BioNTech, Pfizer Vaccination and Immunoglobulin G Response Against SARS-CoV-2 in the Individuals Tested Positive for COVID-19: A Randomized Control Trial

Background

Vitamin D participates in the biological function of the innate and adaptive immune system and inflammation. We aim to specify the effectiveness of the vitamin D supplementation on the side effects BioNTech, Pfizer vaccination, and immunoglobulin G response against severe acute respiratory syndrome coronavirus 2 in subjects tested positive for coronavirus disease 2019 (COVID-19).

Methods

In this multi-center randomized clinical trial, 498 people tested positive for COVID-19 were divided into 2 groups, receiving vitamin D capsules or a placebo (1 capsule daily, each containing 600 IU of vitamin D) over 14-16 weeks. Anthropometric indices and biochemical parameters were measured before and after the second dose of vaccination.

Result

Fourteen to 16 weeks after supplementation, the intervention group had an immunoglobulin G (IgG) increase of 10.89 ± 1.2 g/L, while the control group had 8.89 ± 1.3 g/L, and the difference was significant between both groups (p = 0.001). After the second dose of vaccination, the supplement group significantly increased their 25-hydroxy vitamin D from initially 28.73 ± 15.6 ng/mL and increased to 46.48 ± 27.2 ng/mL, and the difference between them was significant. Those with a higher body mass index (BMI) had the most of symptoms, and the difference of side effects according to BMI level was significantly different. In 8 weeks after supplementation obese participants had the lowest IgG levels than overweight or normal subjects. The proportion of all types of side effects on the second dose was significantly diminished compared with the first dose in the intervention group.

Conclusion

Supplementation of 600 IU of vitamin D3 can reduce post-vaccination side effects and increase IgG levels in participants who received BioNTech, Pfizer vaccine.

Trial Registration

ClinicalTrials.gov Identifier: NCT05851313.

Influence of Vitamin D on Periodontal Inflammation: A Review

The active form of vitamin D is the hormonally active 1,25(OH)2D3 (Vit D) vitamin, which plays an important role in bone biology and host immunity. The vitamin D receptor (VDR) is a nuclear ligand-dependent transcription factor expressed by many cells. Ligation of VDR by VitD regulates a wide plethora of genes and physiologic functions through the formation of the complex Vit D-VDR signaling cascade. The influence of Vit D-VDR signaling in host immune response to microbial infection has been of interest to many researchers. This is particularly important in oral health and diseases, as oral mucosa is exposed to a complex microbiota, with certain species capable of causing disruption to immune homeostasis. In this review, we focus on the immune modulatory roles of Vit D in the bone degenerative oral disease, periodontitis.

The changes of Treg and Th17 cells relate to serum 25(OH)D in patients with initial-onset childhood systemic lupus erythematosus

Background

T helper 17 (Th17) cells and regulatory T cells (Treg) are known to play a crucial role in the pathogenesis of systemic lupus erythematosus (SLE). Improving the balance between Treg and Th17 cells can be a promising new therapeutic target in SLE patients. Vitamin D has a significant impact on the immune inflammatory process and the immune cells involved in this process. The purpose of this study is to investigate the relationship between Th17, Treg, cytokines, and serum 25 hydroxyvitamin D [25(OH)D] in patients with initial-onset childhood SLE.

Methods

A total of 82 children aged <18 years with initial-onset SLE were included, as well as 60 healthy subjects during the same period at the Pediatrics Department of the Second Hospital of Hebei Medical University. The chemiluminescence method was performed to detect serum 25(OH)D levels. Flow cytometry was used to evaluate Treg and Th17 cells. An enzyme-linked immunosorbent assay kit was used to evaluate plasma interleukin (IL)-23, IL-17, IL-10, IL-6, and tumor necrosis factor alpha (TNF-α) concentrations.

Result

The serum 25(OH)D levels in patients with initial-onset childhood SLE were significantly lower than those in the healthy controls. The proportion of lupus nephritis (LN) was higher in the vitamin D insufficiency group (71.4%) compared with the vitamin D sufficiency group (30.3%) (p < 0.05). The SLE disease activity index (SLEDAI) was higher in the vitamin D insufficiency group (median = 14) than that in the vitamin D sufficiency group (median = 9) (p < 0.05).The 25(OH)D level was positively correlated with the Treg ratio (r = 0.337, p = 0.002), and it was negatively correlated with the Th17 cell ratio (r = -0.370, p = 0.001). The serum 25(OH)D level had a negative correlation with IL-23 (r = -0.589, p < 0.001), IL-17(r = -0.351, p = 0.001), TNF-α (r = -0.283, p = 0.01), IL-6 (r = -0.392, p < 0.001), and IL-10 (r = -0.313, p = 0.004) levels.

Conclusion

The serum 25(OH)D levels decreased in patients with initial-onset childhood SLE. There was a negative correlation between the serum 25(OH)D levels and SLEDAI. The serum 25(OH)D levels in patients with initial-onset childhood SLE were negatively correlated with the Th17 ratio and related cytokines, while positively correlated with the Treg ratio.

Vitamin D3 attenuates SARS-CoV-2 nucleocapsid protein-caused hyperinflammation by inactivating the NLRP3 inflammasome through the VDR-BRCC3 signaling pathway in vitro and in vivo

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-caused coronavirus disease 2019 (COVID-19) is a global crisis with no satisfactory therapies. Vitamin D3 (VD3) is considered a potential candidate for COVID-19 treatment; however, little information is available regarding the exact effects of VD3 on SARS-CoV-2 infection and the underlying mechanism. Herein, we confirmed that VD3 reduced SARS-CoV-2 nucleocapsid (N) protein-caused hyperinflammation in human bronchial epithelial (HBE) cells. Meanwhile, VD3 inhibited the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome activation in N protein-overexpressed HBE (HBE-N) cells. Notably, the inhibitors of caspase-1, NLRP3, and NLRP3 or caspase-1 small interference RNA (siRNA) enhanced VD3-induced NLRP3 inflammasome inactivation, with subsequent suppression of interleukin-6 (IL6) and IL1β release in HBE-N cells, which were abolished by the NLRP3 agonist. Moreover, VD3 increased NLRP3 ubiquitination (Ub-NLRP3) expression and the binding of the VDR with NLRP3, with decreased BRCA1/BRCA2-containing complex subunit 3 (BRCC3) expression and NLRP3-BRCC3 association. VD3-induced Ub-NLRP3 expression, NLRP3 inflammasome inactivation, and hyperinflammation inhibition were improved by the BRCC3 inhibitor or BRCC3 siRNA, which were attenuated by the vitamin D receptor (VDR) antagonist or VDR siRNA in HBE-N cells. Finally, the results of the in vivo study in AAV-Lung-enhanced green fluorescent protein-N-infected lungs were consistent with the findings of the in vitro experiment. In conclusion, VD3 attenuated N protein-caused hyperinflammation by inactivating the NLRP3 inflammasome partially through the VDR-BRCC3 signaling pathway.

Microglia and Brain Disorders: The Role of Vitamin D and Its Receptor

Accounting for 5-20% of the total glial cells present in the adult brain, microglia are involved in several functions: maintenance of the neural environment, response to injury and repair, immunesurveillance, cytokine secretion, regulation of phagocytosis, synaptic pruning, and sculpting postnatal neural circuits. Microglia contribute to some neurodevelopmental disorders, such as Nasu-Hakola disease (NHD), Tourette syndrome (TS), autism spectrum disorder (ASD), and schizophrenia. Moreover, microglial involvement in neurodegenerative diseases, such as Alzheimer's (AD) and Parkinson's (PD) diseases, has also been well established. During the last two decades, epidemiological and research studies have demonstrated the involvement of vitamin D3 (VD3) in the brain's pathophysiology. VD3 is a fat-soluble metabolite that is required for the proper regulation of many of the body's systems, as well as for normal human growth and development, and shows neurotrophic and neuroprotective actions and influences on neurotransmission and synaptic plasticity, playing a role in various neurological diseases. In order to better understand the exact mechanisms behind the diverse actions of VD3 in the brain, a large number of studies have been performed on isolated cells or tissues of the central nervous system (CNS). Here, we discuss the involvement of VD3 and microglia on neurodegeneration- and aging-related diseases.

Immunomodulatory actions of vitamin D in various immune-related disorders: a comprehensive review

For many years, vitamin D has been acknowledged for its role in maintaining calcium and phosphate balance. However, in recent years, research has assessed its immunomodulatory role and come up with conflicting conclusions. Because the vitamin D receptor is expressed in a variety of immune cell types, study into the precise role of this molecule in diseases, notably autoimmune disorders, has been made possible. The physiologically activated version of vitamin D also promotes a tolerogenic immunological condition in addition to modulating innate and acquired immune cell responses. According to a number of recent studies, this important micronutrient plays a complex role in numerous biochemical pathways in the immune system and disorders that are associated with them. Research in this field is still relatively new, and some studies claim that patients with severe autoimmune illnesses frequently have vitamin D deficiencies or insufficiencies. This review seeks to clarify the most recent research on vitamin D's immune system-related roles, including the pathophysiology of major disorders.

A meta-analysis of the association between vitamin D supplementation and the risk of acute respiratory tract infection in the healthy pediatric group

No previous meta-analysis had explored the association between vitamin D supplementation in healthy pediatrics and the risk of acute respiratory tract infections (ARTIs). Thus, we meta-analyzed the current evidence in this regard to provide sufficient knowledge about this risk-benefit ratio for vitamin D supplementation in this specific age group. We searched seven databases for randomized controlled trials (RCTs) that investigated the effect of vitamin D supplementation and ARTIs risk on a healthy pediatric population (0-18 years old). Meta-analysis was performed through R software. We included eight RCTs after the screening of 326 records according to our eligibility criteria. There were comparable infection rates between Vitamin D and placebo groups (OR = 0.98, 95% CI = 0.90-1.08, P-value = 0.62), with no significant heterogeneity among the included studies (I² = 32%; P-value = 0.22). Moreover, there was no significant difference between the two vitamin D regimens (OR = 0.85, 95% CI = 0.64-1.12, P-value = 0.32), with no considerable heterogeneity among the included studies (I² = 37%; P-value = 0.21). However, there was a significant reduction in Influenza A rates in the high-dose vitamin D group compared to the low dose one (OR = 0.39, 95% CI = 0.26-0.59, P-value < 0.001), with no heterogeneity among the included studies (I² = 0%; P-value = 0.72). Only two studies of 8,972 patients reported different side effects, with overall acceptable safety profile. Regardless of the dosing regimen used or the type of infection, in the healthy pediatric group, there is no evident benefit of using vitamin D to prevent or reduce the ARTI rates.

Role of Coactivator Associated Arginine Methyltransferase 1 (CARM1) in the Regulation of the Biological Function of 1,25-Dihydroxyvitamin D3

1,25-Dihydroxyvitamin D3 (1,25(OH)₂D₃), the hormonally active form of vitamin D, activates the nuclear vitamin D receptor (VDR) to mediate the transcription of target genes involved in calcium homeostasis as well as in non-classical 1,25(OH)₂D₃ actions. In this study, CARM1, an arginine methyltransferase, was found to mediate coactivator synergy in the presence of GRIP1 (a primary coactivator) and to cooperate with G9a, a lysine methyltransferase, in 1,25(OH)₂D₃ induced transcription of Cyp24a1 (the gene involved in the metabolic inactivation of 1,25(OH)₂D₃). In mouse proximal renal tubule (MPCT) cells and in mouse kidney, chromatin immunoprecipitation analysis demonstrated that dimethylation of histone H3 at arginine 17, which is mediated by CARM1, occurs at Cyp24a1 vitamin D response elements in a 1,25(OH)₂D₃ dependent manner. Treatment with TBBD, an inhibitor of CARM1, repressed 1,25(OH)₂D₃ induced Cyp24a1 expression in MPCT cells, further suggesting that CARM1 is a significant coactivator of 1,25(OH)₂D₃ induction of renal Cyp24a1 expression. CARM1 was found to act as a repressor of second messenger-mediated induction of the transcription of CYP27B1 (involved in the synthesis of 1,25(OH)₂D₃), supporting the role of CARM1 as a dual function coregulator. Our findings indicate a key role for CARM1 in the regulation of the biological function of 1,25(OH)₂D₃.

Vitamin D and Autoimmune Rheumatic Diseases

Vitamin D is a steroid hormone with potent immune-modulating properties. It has been shown to stimulate innate immunity and induce immune tolerance. Extensive research efforts have shown that vitamin D deficiency may be related to the development of autoimmune diseases. Vitamin D deficiency has been observed in patients with rheumatoid arthritis (RA) and has been shown to be inversely related to disease activity. Moreover, vitamin D deficiency may be implicated in the pathogenesis of the disease. Vitamin D deficiency has also been observed in patients with systemic lupus erythematosus (SLE). It has been found to be inversely related to disease activity and renal involvement. In addition, vitamin D receptor polymorphisms have been studied in SLE. Vitamin D levels have been studied in patients with Sjogren's syndrome, and vitamin D deficiency may be related to neuropathy and the development of lymphoma in the context of Sjogren's syndrome. Vitamin D deficiency has been observed in ankylosing spondylitis, psoriatic arthritis (PsA), and idiopathic inflammatory myopathies. Vitamin D deficiency has also been observed in systemic sclerosis. Vitamin D deficiency may be implicated in the pathogenesis of autoimmunity, and it may be administered to prevent autoimmune disease and reduce pain in the context of autoimmune rheumatic disorders.

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

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

The preventive role of vitamin D in the prevention and management of Fibromyalgia syndrome

Aim: Vitamin D deficiency is a prevalent condition among the general population, all around the world. Vitamin D deficiency is defined as serum levels of 25-hydroxy vitamin D lower than 20 ng/ml (50 nmol/ml). It is a known actor in the skeletal system through the regulation of calcium and phosphate metabolism and bone mineralization. Still, the role of vitamin D as an immunomodulator is yet to be acknowledged by healthcare practitioners as a cause, precipitating factor, and contributor to a variety of diseases. Vitamin D is shown to be an actor in multiple sclerosis, rheumatoid arthritis, insulin-dependent diabetes mellitus, and irritable bowel syndrome. Fibromyalgia syndrome (FMS) is a chronic disorder associated with a severe pain that can affect a patient's musculoskeletal system, daily routine, and mood. The clinical presentation encapsulates other disorders such as lethargy and sleep problems, brain fog and other cognitive issues, and physical and psychiatric symptoms. Methods: We have used PubMed and ResearchGate in the reviewing process of our paper. We tried to address as many topics as we judged to be adequate and relevant for the practicing clinicians. Results: Management of fibromyalgia syndrome is both nonpharmacologic and pharmacologic, which are provided in a stepwise fashion. Yet, the management of FMS remains a challenge, heeding a multidisciplinary approach. Among the dietary interventions, we chose vitamin D and its effects on FMS. Literature shows that supplementation improves pain caused by fibromyalgia syndrome, yet specific recommendations are still to be created. Conclusions: We call on all the relevant governmental bodies, public health experts and health policy makers, healthcare practitioners, and the civil society to use novel data related to fibromyalgia syndrome, and in a broader perspective, the integral role of vitamin D.

Vitamin D: sources, physiological role, biokinetics, deficiency, therapeutic use, toxicity, and overview of analytical methods for detection of vitamin D and its metabolites

Vitamin D has a well-known role in the calcium homeostasis associated with the maintenance of healthy bones. It increases the efficiency of the intestinal absorption of dietary calcium, reduces calcium losses in urine, and mobilizes calcium stored in the skeleton. However, vitamin D receptors are present ubiquitously in the human body and indeed, vitamin D has a plethora of non-calcemic functions. In contrast to most vitamins, sufficient vitamin D can be synthesized in human skin. However, its production can be markedly decreased due to factors such as clothing, sunscreens, intentional avoidance of the direct sunlight, or the high latitude of the residence. Indeed, more than one billion people worldwide are vitamin D deficient, and the deficiency is frequently undiagnosed. The chronic deficiency is not only associated with rickets/osteomalacia/osteoporosis but it is also linked to a higher risk of hypertension, type 1 diabetes, multiple sclerosis, or cancer. Supplementation of vitamin D may be hence beneficial, but the intake of vitamin D should be under the supervision of health professionals because overdosing leads to intoxication with severe health consequences. For monitoring vitamin D, several analytical methods are employed, and their advantages and disadvantages are discussed in detail in this review.

Proper Dietary and Supplementation Patterns as a COVID-19 Protective Factor (Cross-Sectional Study-Silesia, Poland)

BACKGROUND

The COVID-19 pandemic has become a challenge for the world today, so it is very important to create healthy eating habits in society to support immunity and raise awareness of the benefits of supplementation.

OBJECTIVE

The purpose of this study is to evaluate diet and dietary supplementation, since previous studies indicate the protective nature of these in building immunity during the pandemic and post-pandemic period (COVID-19). The hypothesis of the study is whether the dietary regimen presented by the COVID-19 respondents can be considered protective in building immunity against SARS-CoV-2.

MATERIAL AND METHODS

The study included 304 subjects, with an average age of 39.04 ± 23.59. The main criteria for inclusion in the study were that the respondent was ≥18 years old and participated voluntarily. The study was conducted using an original questionnaire.

RESULTS

In the study group, no change was noticed in the previous diet during the COVID-19 pandemic, while the level of physical activity among the respondents decreased. Too low a percentage of people regularly consumed, among other foods. legume seeds-only 10.5% of respondents consumed them several times a week-and citrus fruits-the largest number of respondents, as many as 39.8%, only consumed them several times a month. The largest percentage of respondents with mild/scanty COVID-19 disease regularly took vitamin C-containing preparations (n = 61; 59.80%). Statistical analysis showed that there was a correlation between the incidence of mild/scanty COVID-19 and the regularity of taking vitamin C-containing preparations (T = 11.374; r = 0.611; p = 0.04603). A statistical significance level was also obtained for the regularity of supplementation of multivitamin preparations, which were taken by 68% (34) of respondents affected by mild/scanty COVID-19 (T = 13.456; r = 0.711; p = 0.02191).

CONCLUSIONS

The study's hypothesis was supported. Respondents characterized by a normal dietary pattern and taking supplements commonly recognized as immune "boosters" were more likely to mildly survive COVID-19. Moreover, it was shown that the pandemic in most of the respondents did not significantly affect their dietary strategy. It is reasonable to conclude that the dietary patterns adopted may be a common way to prevent SARS-CoV-2 infections and their possible complications.

Vitamin D Insufficiency and Clinical Outcomes with Chimeric Antigen Receptor T-Cell Therapy in Large B-cell Lymphoma

Vitamin D insufficiency is a potentially modifiable risk factor for poor outcomes in newly diagnosed large B-cell lymphoma (LBCL). However, the role of circulating vitamin D concentrations in relapsed/refractory LBCL treated with CD19-directed chimeric antigen receptor T-cell therapy (CAR-T) is currently unknown. This was a single-center, observational study that evaluated the association of pre-CAR-T 25-hydroxyvitamin D (25-OHD) status with 100-day complete response, progression-free survival, overall survival, and CAR-T-related toxicity in 111 adult relapsed/refractory LBCL patients. Vitamin D insufficiency was defined as ≤30 ng/mL in accordance with the Endocrine Society guidelines. The median pre-CAR-T 25-hydroxyvitamin D concentration was 24 ng/mL (interquarile range = 18-34). Vitamin D-insufficient patients (≤30 ng/mL; n = 73 [66%]) were significantly younger than their vitamin D-replete (>30 ng/mL; n = 38 [34%]) counterparts (P= .039). The vitamin D-insufficient cohort was enriched for de novo LBCL as the histological subtype (P= .026) and had a higher proportion of tisagenlecleucel as the CAR-T product (P= .049). There were no other significant differences in the baseline characteristics between the two groups. In vitamin D-insufficient compared to -replete patients, 100-day complete response was 55% versus 76% (P= .029), and 2-year overall survival was 41% versus 71% (P= .061), respectively. In multivariate analysis, vitamin D insufficiency remained significantly associated with 100-day complete response (odds ratio 2.58 [1.05-6.83]; P= .045) and overall survival (hazard ratio 2.24 [1.08-4.66], P= .030). In recipients of tisagenlecleucel, vitamin D insufficiency was associated with significantly lower cell viability of the infused CAR-T product (P= .015). Finally, pretreatment vitamin D insufficiency did not predict for subsequent CAR-T-related toxicity. This is the first report to demonstrate that vitamin D insufficiency is associated with inferior clinical outcomes in CAR-T recipients. Further study into the mechanistic insights of this finding, and the potential role of vitamin D supplementation to optimize CAR-T are warranted.

Oxidative stress in Hashimoto's thyroiditis: possible adjuvant therapies to attenuate deleterious effects

A number of studies have shown that oxidative stress is related to the pathogenesis of several immunological diseases, such as Hashimoto's thyroiditis (HT), although there is no plausible mechanism to explain it. Thus, we aimed at hypothesizing and providing some possible mechanisms linking oxidative stress to autoimmunity aspects and its implications for HT, as well as adjuvant therapeutic proposals to mitigate the deleterious effects. Our hypothesis is that deficient eating habits, autoimmune regulator gene predisposing gene, dysbiosis and molecular mimicry, unfolded proteins and stress in the endoplasmic reticulum, and thymus involution appear to be the main potential factors leading to HT oxidative stress. Likewise, we show that the use of minerals selenium and zinc, vitamins D and C, as well as probiotics, can be interesting adjuvant therapies for the control of oxidative damage and poor prognosis of HT. Further clinical trials are needed to understand the real beneficial and side effects of these supplements.

Host-directed therapies in pulmonary tuberculosis: Updates on anti-inflammatory drugs

Tuberculosis (TB) is a lethal disease and remains one of the top ten causes of mortality by an infectious disease worldwide. It can also result in significant morbidity related to persistent inflammation and tissue damage. Pulmonary TB treatment depends on the prolonged use of multiple drugs ranging from 6 months for drug-susceptible TB to 6-20 months in cases of multi-drug resistant disease, with limited patient tolerance resulting from side effects. Treatment success rates remain low and thus represent a barrier to TB control. Adjunct host-directed therapy (HDT) is an emerging strategy in TB treatment that aims to target the host immune response to Mycobacterium tuberculosis in addition to antimycobacterial drugs. Combined multi-drug treatment with HDT could potentially result in more effective therapies by shortening treatment duration, improving cure success rates and reducing residual tissue damage. This review explores the rationale and challenges to the development and implementation of HDTs through a succinct report of the medications that have completed or are currently being evaluated in ongoing clinical trials.

Vitamin D status: a U-shaped relationship for SARS-CoV-2 seropositivity in UK healthcare workers

BACKGROUND

There is increasing evidence that vitamin D (VD) deficiency may increase individuals' risk of COVID-19 infection and susceptibility. We aimed to determine the relationship between VD deficiency and sufficiency and COVID-19 seropositivity within healthcare workers.

METHODS

The study included an observational cohort of healthcare workers who isolated due to COVID-19 symptoms from 12 May to 22 May 2020, from the University Hospitals Birmingham National Health Service Foundation Trust. Data collected included SARS-CoV-2 seroconversion status, serum 25(OH)D₃ levels, age, body mass index (BMI), sex, ethnicity, job role and comorbidities. Participants were grouped into four VD categories: (1) Severe VD deficiency (VD<30 nmol/L); (2) VD deficiency (30 nmol/L ≤VD<50 nmol/L); (3) VD insufficiency (50 nmol/L ≤VD<75 nmol/L); (4) VD sufficiency (VD≥75 nmol/L).

RESULTS

When VD levels were compared against COVID-19 seropositivity rate, a U-shaped curve was identified. This trend repeated when participants were split into subgroups of age, sex, ethnicity, BMI and comorbidity status. Significant difference was identified in the COVID-19 seropositivity rate between VD groups in the total population and between groups of men and women; black, Asian and minority ethnic (BAME) group; BMI<30 (kg/m²); 0 and +1 comorbidities; the majority of which were differences when the severely VD deficient category were compared with the other groups. A larger proportion of those within the BAME group (vs white ethnicity) were severely VD deficient (p<0.00001). A larger proportion of the 0 comorbidity subgroup were VD deficient in comparison to the 1+ comorbidity subgroup (p=0.046).

CONCLUSIONS

Our study has shown a U-shaped relationship for COVID-19 seropositivity in UK healthcare workers. Further investigation is required to determine whether high VD levels can have a detrimental effect on susceptibility to COVID-19 infection. Future randomised clinical trials of VD supplementation could potentially identify 'optimal' VD levels, allowing for targeted therapeutic treatment for those at risk.

Case-control study of vitamin D status and adult multidrug-resistant pulmonary TB

BACKGROUND: India has the highest prevalence of multidrug-resistant TB (MDR-TB) globally. Vitamin D deficiency is potentially an important risk factor for MDR-TB.METHODS: We conducted a case-control study of 90 newly diagnosed adult MDR-TB cases, 180 household controls and 82 non-household controls in Mumbai, India. Serum 25-hydroxyvitamin D (25(OH)D), anthropometry, clinical status and history, dietary data and sociodemographic data were collected from each participant. Interferon-gamma release assay (IGRA) was also performed in controls to assess latent TB. Multivariable regression was performed to estimate associations between 25(OH)D vs. case status and IGRA positivity.RESULTS: Mean participant age was 33.8 ± 12.0 years; 72.8% had 25(OH)D <20 ng/ml. Mean 25(OH)D was significantly (P < 0.05) lower in cases (12.5 ± 7.9) than both household (17.5 ± 11.2) and non-household controls (16.4 ± 9.1). In multivariable models, 25(OH)D concentration was inversely associated with MDR-TB case status among cases and household controls (OR 0.95 per 1 ng/ml, 95% CI 0.92-0.99; P = 0.015), and among cases and non-household controls (OR 0.94 per 1 ng/ml, 95% CI 0.89-1.00; P = 0.033); 53.6% of controls were IGRA-positive. 25(OH)D status was not associated with IGRA positivity.CONCLUSION: Vitamin D status was independently associated with MDR-TB case status. Research should evaluate the effectiveness of vitamin D supplementation in prevention and adjunctive treatment of MDR-TB.

Role of Vitamin D in Liver Disease and Complications of Advanced Chronic Liver Disease

Vitamin D is a crucial nutrient with many pleiotropic effects on health and various chronic diseases. The purpose of this review is to provide a detailed report on the pathophysiological mechanisms underlying vitamin D deficiency in patients with chronic liver disease, addressing the different liver etiologies and the condition of advanced chronic liver disease (cirrhosis) with related complications. To date, patients with liver disease, regardless of underlying etiology, have been shown to have reduced levels of vitamin D. There is also evidence of the predictive role of vitamin D values in complications and progression of advanced disease. However, specific indications of vitamin D supplementation are not conclusive concerning what is already recommended in the general population. Future studies should make an effort to unify and validate the role of vitamin D supplementation in chronic liver disease.

Effect of Vitamin D Supplementation on CD4 Count in HIV-Infected Children and Adolescents in North India: A Non-Randomized Comparative Study

BACKGROUND

HIV infection is still a serious public health issue globally. Suboptimal vitamin D status is highly prevalent in HIV-infected children and adolescents throughout the world.

OBJECTIVES

To evaluate the outcome of vitamin D supplementation on CD4 count in HIV-infected children and adolescents with suboptimal vitamin D status.

METHODS

Vitamin D level of HIV-infected children and adolescents were measured at enrolment. Suboptimal vitamin D level was defined as 25(OH)D < 30 ng/ml. Vitamin D insufficiency and deficiency were defined as 21-29 and <20 ng/ml, respectively. Children with suboptimal vitamin D levels were supplemented with vitamin D.

RESULTS

This was a single-centre, non-randomized comparative study enrolling 50 eligible participants. There were 20 patients who were vitamin D sufficient, 7 were vitamin D insufficient and 23 were found to be vitamin D deficient at enrolment. However, after supplementation, the status of sufficient remained same and 7 insufficient become sufficient, whereas in 23 deficient, 18 (78.3%) become sufficient and 5 (21.7%) become insufficient and this change was found statistically significant among the groups (χ2 = 6.52, p = 0.038). There was a significant improvement of CD4 count from baseline to 4 months in deficient group on vitamin D supplementation (p value < 0.001; 1.2-fold rise). No significant change was seen in vitamin D insufficient (p value = 0.791) and sufficient groups (p value = 0.168).

CONCLUSION

Vitamin D should be supplemented in HIV-infected children on ART with low CD4 counts.

[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.

A Vitamin D-RelB/NF-κB Pathway Limits Chandipura Virus Multiplication by Rewiring the Homeostatic State of Autoregulatory Type 1 IFN-IRF7 Signaling

Besides its functions in the skeletomuscular system, vitamin D is known to alleviate viral-inflicted pathologies. However, the mechanism underlying protective vitamin D function remains unclear. We examined the role of vitamin D in controlling cellular infections by Chandipura virus, an RNA virus implicated in human epidemics. How immune signaling pathways, including those regulating NF-κB and IFN regulatory factors (IRFs), are activated in virus-infected cells has been well studied. Our investigation involving human- and mouse-derived cells revealed that vitamin D instructs the homeostatic state of these antiviral pathways, leading to cellular resilience to subsequent viral infections. In particular, vitamin D provoked autoregulatory type 1 IFN-IRF7 signaling even in the absence of virus infection by downmodulating the expression of the IFN-inhibitory NF-κB subunit RelB. Indeed, RelB deficiency rendered vitamin D treatment redundant, whereas IRF7 depletion abrogated antiviral vitamin D action. In sum, immune signaling homeostasis appears to connect micronutrients to antiviral immunity at the cellular level. The proposed link may have a bearing on shaping public health policy during an outbreak.

Positive Effects of Vitamin D Supplementation in Patients Hospitalized for COVID-19: A Randomized, Double-Blind, Placebo-Controlled Trial

Retrospective studies showed a relationship between vitamin D status and COVID-19 severity and mortality, with an inverse relation between SARS-CoV-2 positivity and circulating calcifediol levels. The objective of this pilot study was to investigate the effect of vitamin D supplementation on the length of hospital stay and clinical improvement in patients with vitamin D deficiency hospitalized with COVID-19. The study was randomized, double blind and placebo controlled. A total of 50 subjects were enrolled and received, in addition to the best available COVID therapy, either vitamin D (25,000 IU per day over 4 consecutive days, followed by 25,000 IU per week up to 6 weeks) or placebo. The length of hospital stay decreased significantly in the vitamin D group compared to the placebo group (4 days vs. 8 days; p = 0.003). At Day 7, a significantly lower percentage of patients were still hospitalized in the vitamin D group compared to the placebo group (19% vs. 54%; p = 0.0161), and none of the patients treated with vitamin D were hospitalized after 21 days compared to 14% of the patients treated with placebo. Vitamin D significantly reduced the duration of supplemental oxygen among the patients who needed it (4 days vs. 7 days in the placebo group; p = 0.012) and significantly improved the clinical recovery of the patients, as assessed by the WHO scale (p = 0.0048). In conclusion, this study demonstrated that the clinical outcome of COVID-19 patients requiring hospitalization was improved by administration of vitamin D.

Dietary Component-Induced Inflammation and Its Amelioration by Prebiotics, Probiotics, and Synbiotics

A balanced diet with many dietary components maintains immune homeostasis directly by interacting with innate and adaptive immune components or indirectly through gut microbiota and their metabolites. Dietary components may inhibit pro-inflammatory mediators and promote anti-inflammatory functions or vice versa. Western diets with imbalanced dietary components skew the immune balance toward pro-inflammation and induce intestinal inflammation, consequently leading to many intestinal and systemic inflammatory diseases like ulcerative colitis, Crohn's disease, irritable bowel syndrome, cardiovascular problems, obesity, and diabetes. The dietary component-induced inflammation is usually chronic in nature and frequently caused or accompanied by alterations in gut microbiota. Therefore, microbiome-targeted therapies such as probiotics, prebiotics and synbiotics hold great potentials to amend immune dysregulation and gut dysbiosis, preventing and treating intestinal and systemic inflammatory diseases. Probiotics, prebiotics and synbioitcs are progressively being added to foods and beverages, with claims of health benefits. However, the underlining mechanisms of these interventions for preventing and treating dietary component-induced inflammation are still not very clear. In addition, possibly ineffective or negative consequences of some probiotics, prebiotics and synbiotics call for stringent testing and regulation. Here, we will first briefly review inflammation, in terms of its types and the relationship between different dietary components and immune responses. Then, we focus on current knowledge about the direct and indirect effects of probiotics, prebiotics and synbiotics on intestinal and systemic inflammation. Understanding how probiotics, prebiotics and synbiotics modulate the immune system and gut microbiota will improve our strategies for preventing and treating dietary component-induced intestinal inflammation and inflammatory diseases.

The association between vitamin D levels and oxidative stress markers in Egyptian Behcet's disease patients

BACKGROUND

Oxidative stress is postulated to have a major role in the pathophysiology of Bechet's Disease (BD). Growing evidence suggests that vitamin D has important roles in enhancing the expression of anti-inflammatory cytokines as well as certain antioxidants. However, there is little evidence currently about the antioxidant properties of vitamin D in BD.

OBJECTIVE

To study the relationship between vitamin D levels and the oxidative stress markers in patients with BD in addition to its association with disease activity and severity.

METHODS

Sixty BD patients (45 males, 15 females; mean age: 34.2 ± 9.6 years) were enrolled in this study and compared to a sex and age matched control group. Plasma 25-Hydroxy vitamin D (25-OH-D) was measured using Human (25-OH-D) ELISA assay. Plasma malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), superoxide dismutase (SOD) activity, catalase (CAT) activity and total antioxidant capacity (TAC) were determined by spectrophotometric methods in both groups. Plasma calcium (Ca) was measured by ELISA assay.

RESULTS

When compared to controls vitamin D, GSH, CAT activity, TAC and Ca were significantly lower in BD patients, while MDA and NO levels were significantly increased in BD patients. Our Results Found that vitamin D was inversely correlated to BD current Activity form (BDCAF), disease severity score, ESR, CRP, MDA and NO, while vitamin D was significantly positively correlated to GSH, SOD, TAC and Ca.

CONCLUSION

Our study confirms that a lower level of vitamin D is associated with the oxidative stress state in BD patients as detected by MDA and NO elevation as well as decreased GSH, SOD activity, CAT activity and TAC. Hence, Vitamin D fortified foods and beverages or supplementation may improve disease severity and oxidative stress in BD patients.

Temporal Association of Reduced Serum Vitamin D with COVID-19 Infection: Two Single-Institution Case–Control Studies

(1) Background: Vitamin D supplementation has been proposed for the prevention and treatment of COVID-19, but it is not clear if reduced serum vitamin D predisposes individuals to COVID-19 and/or is a secondary consequence of infection. This study assessed the temporal association between serum vitamin D and COVID-19 with two single-institution case–control studies through the University of California San Diego (UCSD) Health System. (2) Methods: This study included patients who tested positive for COVID-19 from 1 January to 30 September 2020 with serum 25-hydroxy-vitamin D (25(OH)D) measured within 180 days of diagnosis. Patients were separated based on whether 25(OH)D was measured before (n = 107 cases, 214 controls) or after (n = 203 cases, 406 controls) COVID-19 diagnosis. COVID-19 infection status was the outcome variable in the pre-diagnosis study, whereas serum 25(OH)D level was the outcome variable in the post-diagnosis study. (3) Results: Serum 25(OH)D levels were not associated with the odds of subsequent COVID-19 infection (OR 1.0, 95% CI: 1.0 to 1.0, p = 0.98). However, COVID-19-positive individuals had serum 25(OH)D measurements that were 2.7 ng/mL lower than the controls (95% CI: −5.2 to −0.2, p = 0.03). (4) Conclusions: In our study population, serum 25(OH)D levels were not associated with the risk of acquiring COVID-19 infection but were reduced in subjects after COVID-19 infection. These results support the possibility that reduced serum 25(OH)D is a consequence and not a cause of COVID-19 infection.

Vitamin D Deficiency and Comorbidities as Risk Factors of COVID-19 Infection: A Systematic Review and Meta-analysis

OBJECTIVES

Extensive evidence links low vitamin D status and comorbidities with coronavirus disease 2019 (COVID-19) outcomes, but the results of published studies are contradictory. Therefore, we investigated the association of lower levels of vitamin D and comorbidities with the risk of COVID-19 infection.

METHODS

We searched MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov for articles published until August 20, 2021. Sixteen eligible studies were identified (386 631 patients, of whom 181 114 were male). We included observational cohort and case-control studies that evaluated serum levels of vitamin D in COVID-19-positive and COVID-19-negative patients. Mean differences (MDs) with 95% confidence intervals (CIs) were calculated.

RESULTS

Significantly lower vitamin D levels were found in COVID-19-positive patients (MD, -1.70; 95% CI, -2.74 to -0.66; p=0.001), but with variation by study design (case-control: -4.04; 95% CI, -5.98 to -2.10; p<0.001; cohort: -0.39; 95% CI, -1.62 to 0.84; p=0.538). This relationship was more prominent in female patients (MD, -2.18; 95% CI, -4.08 to -0.28; p=0.024) than in male patients (MD, -1.74; 95% CI, -3.79 to 0.31; p=0.096). Male patients showed higher odds of having low vitamin D levels (odds ratio [OR], 2.09; 95% CI, 1.38 to 3.17; p<0.001) than female patients (OR, 1.17; 95% CI, 0.74 to 1.86; p=0.477). Comorbidities showed inconsistent, but generally non-significant, associations with COVID-19 infection.

CONCLUSIONS

Low serum vitamin-D levels were significantly associated with the risk of COVID-19 infection. This relationship was stronger in female than in male COVID-19 patients. Limited evidence was found for the relationships between comorbidities and COVID-19 infection, warranting large population-based studies to clarify these associations.

Oral vitamin D3 supplementation for femtosecond LASIK-associated dry eye vitamin D for LASIK dry eye syndrome

PURPOSE

To assess the effect of oral vitamin D₃ supplementation in dry eye after femtosecond laser-assisted in situ keratomileusis (FS-LASIK).

SETTING

Liuzhou Worker's Hospital.

DESIGN

This prospective study included 90 patients selected between January and December in 2019, who underwent FS-LASIK operation in our hospital and had obvious symptoms indicating dry eyes 1 month after operation. The subjects were randomly divided into two groups: The experimental group (n = 45) received vitamin D3 2000 IU/D continuously for 12 weeks; the control group (n = 45) did not take vitamin D3 orally. Ocular surface disease index (OSDI), Tear breakup time (TBUT) and Schirmer's test I were evaluated premedication and 1,3,6 months after treatment. Serum vitamin D3 level and the mean concentration of cytokine IL-6, IL-17, IL-23 in t ears were also measured.

RESULTS

One month after treatment, the mean OSDI score of the experimental group (11.67 ± 8.53) was significantly lower than that of the control group (23.82 ± 13.22) (P = 0.007). TBUT (10.71 ± 1.02 s) and Schirmer I (9.36 ± 0.40 mm) of the experimental group were higher than those of the control group (7.49 ± 1.29 s and 7.51 ± 0.44 mm). The OSDI (10.25 ± 5.49) was significantly lower than those of the control group(20.22 ± 6.23) and TBUT (10.75 ± 1.09 s) and Schirmer I test value (11.34 ± 0.39 mm) of the experimental group were significantly higher than those of the control group (8.36 ± 1.23, 8.12 ± 0.50) at 3 months after treatment. There were significant differences in OSDI, TBUT (P < 0.05) and Schirmer I test value between the two groups at 6 months after treatment. Serum vitamin D₃ level was negatively correlated with OSDI score (r = - 0.90; P = 0.00) and positively correlated with Schirmer I test (r = 0.88; P = 0.00), TBUT score (r = 0.89; P = 0.00) and TMH (r = 0.80; P = 0.00). IL-17 level was shown to be significantly correlated with TBUT(r = - 0.25, P = 0.014) and Schirmer I test (r = - 0.21, P = 0.018). IL-6 level was significantly correlated with OSDI (R = 0.18, P = 0.020) and TBUT (R = 0.20, P = 0.019).

Dietary Supplementations and Depression

Depression is a mood disturbance condition that occurs for more than two weeks in a row, leading to suicide. Due to adverse effects of depression, antidepressants and adjunctive therapies, such as dietary supplementation, are used for treatment. Therefore, this review explored and summarized dietary supplements’ types, dosages, and effectiveness in preventing and treating depression. A literature search of the PubMed database was conducted in August 2021 to identify studies assessing depression, after which scale measurements based on dietary supplements were identified. From the obtained 221 studies, we selected 63 papers. Results showed PUFA (EPA and DHA combination), vitamin D, and probiotics as the most common supplementation used in clinical studies to reduce depressive symptoms. We also observed that although the total daily PUFA dosage that exhibited beneficial effects was in the range of 0.7–2 g EPA and 0.4–0.8 g DHA daily, with an administration period of three weeks to four months, positive vitamin D-based supplementation effects were observed after administering doses of 2000 IU/day or 50,000 IU/week between 8 weeks and 24 months. Alternatively, microbes from the genus Lactobacillus and Bifidobacterium in the probiotic group with a minimum dose of 10⁸ CFU in various dose forms effectively treated depression. Besides, a depression scale was helpful to assess the effect of an intervention on depression. Hence, PUFA, vitamin D, and probiotics were proposed as adjunctive therapies for depression treatment based on the results from this study.

Impact of Vitamin D in Prophylaxis and Treatment in Tuberculosis Patients

Vitamin D plays a crucial role in many infectious diseases, such as tuberculosis (TB), that remains one of the world’s top infectious killers with 1.5 million deaths from TB in 2021. Vitamin D suppresses the replication of Mycobacterium tuberculosis in vitro and showed a promising role in TB management as a result of its connection with oxidative balance. Our review encourages the possible in vivo benefit of a joint administration with other vitamins, such as vitamin A, which share a known antimycobacterial action with vitamin D. However, considering the low incidence of side effects even at high dosages and its low cost, it would be advisable to assess vitamin D level both in patients with active TB and high-risk groups and administer it, at least to reach sufficiency levels.

Changes in optical coherence tomography angiography in patients with vitamin D deficiency

PURPOSE

25-hydroxyvitamin D [25(OH)D] sufficiency has critical biological importance for the human body. Although there are several studies on the association between serum 25(OH)D levels and macular structure, the data in this regard are limited. This study mainly aimed to investigate macular microvascular structure using optical coherence tomography angiography (OCTA) in 25(OH)D deficiency.

STUDY DESIGN

Prospective, single-center, clinical study.

METHODS

The study included 82 eyes of 82 patients with 25(OH)D deficiency (Group I) and 50 eyes of 50 healthy subjects (Group II). All participants underwent OCTA examinations. The foveal avascular zone (FAZ) and superficial capillary plexus (SCP) and deep capillary plexus (DCP) vessel density (VD) measurements of the participants were statistically compared between the patients and healthy subjects.

RESULTS

The mean 25(OH)D levels measured from the venous blood samples of the participants were 7.61 ± 3.27 ng/mL in Group I and 25.39 ± 4.16 ng/mL in Group II, and the difference between these values was statistically significant (p < 0.0001). The FAZ measurement was significantly higher in Group I. The VDs of the SCP and DCP measurements were significantly higher in Group II. When the central macular thickness values of the participants were compared, Group II had a significantly higher value, but there was no significant difference in the central macular volume and retinal nerve fiber layer thickness analyses.

CONCLUSION

The results showed that the FAZ area was significantly higher and the VDs of SCP and DCP were significantly lower in the patients with 25(OH)D deficiency. We found that 25(OH)D deficiency affected macular microvascular architecture.

Fatigue Is Common in Immunoglobulin G Subclass Deficiency and Correlates With Inflammatory Response and Need for Immunoglobulin Replacement Therapy

Purpose

Individuals with immunoglobulin G deficiency (IgGsd) often complain of fatigue. The correlation between systemic inflammation and fatigue is unknown. In this study perceived quality of life (QoL) and fatigue in individuals with IgGsd, on and off immunoglobulin replacement therapy (IgRT) were correlated to inflammatory markers in plasma to identify the subgroup that benefits from IgRT.

Method

Thirty-five IgGsd-patients were sampled on three occasions: at baseline, after being on IgRT for at least 18 months, and 18 months after discontinuation of IgRT. Short form 36, EQ-5D-5L visual analogue scale and fatigue impact scale questionnaires were used for evaluation of QoL and fatigue. Furthermore, a panel of 92 inflammatory markers were analysed in plasma. Thirty-two gender- and age-matched healthy individuals were included as controls and sampled on one occasion.

Results

QoL was lower and perceived fatigue higher in IgGsd compared to the controls. Severe fatigue and low QoL were associated with the need to restart IgRT (which is considered in IgGsd-individuals with a high burden of infections in Sweden). Twenty-five inflammatory factors were dysregulated in IgGsd and the plasma protein patterns were similar regardless of whether IgRT was ongoing or not. Enrichment analysis indicated IL-10 signalling as the most affected pathway. Severe fatigue was associated with decreased levels of the neurotrophic factors VEGFA and CSF-1.

Conclusion

Fatigue is a major contributory factor to impaired health-related QoL in IgGsd and is related to the need for IgRT. Low-grade systemic inflammation is a potential driver of fatigue. In addition to the burden of infections, we suggest the degree of fatigue should be considered when the decision to introduce IgRT is made.

Vitamin D Deficiency in Primary Sjögren's Syndrome: Association with Clinical Manifestations and Immune Activation Markers

Vitamin D is an agent involved in bone and mineral homeostasis. It has been recognized as a potent immunomodulator. It has immune-enhancing properties, and it induces immune tolerance. Vitamin D deficiency has been shown to be related to the development of autoimmune disorders. Vitamin D deficiency has been observed in patients with rheumatoid arthritis (RA) and it has been shown to be related with disease activity. Vitamin D deficiency has also been found in patients with systemic lupus erythematosus (SLE) and it was shown to be related to disease activity and renal involvement. Vitamin D deficiency has also been observed in multiple sclerosis. Vitamin D has been found to act as a supplemental therapeutic agent in multiple sclerosis. Sjögren's syndrome is a systemic autoimmune disease affecting the exocrine glands, known as an autoimmune epithelitis. The disease has a complex pathogenesis, requiring a genetic background, immune cell activation, and autoantibody production. The disease affects the exocrine glands, lacrimal, and salivary glands leading to ocular and oral dryness. Vitamin D levels have been measured in patients with Sjögren's syndrome and an association was observed between low vitamin D levels, peripheral neuropathy and the presence of lymphoma. In other cohorts, such as a Turkish cohort, vitamin D deficiency was observed in patients with Sjögren's syndrome. The aim is to measure serum vitamin D levels in consecutive patients with primary Sjögren's syndrome and investigate the relationship between vitamin D levels and the presence of immunologic markers, clinical, serological, and histopathological characteristics.

The Immunomodulatory Properties of Vitamin D

Since its discovery, vitamin D was shown to have both immunostimulatory and immunomodulatory effects on the immune system. A growing body of evidence so far linked vitamin D deficiency with the development and severity of several systemic and organ specific autoimmune/inflammatory diseases, such as systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, and multiple sclerosis. In the present report, the multiple and diverse effects of vitamin D on the immune system are reviewed.