Role of Vitamin D Beyond the Skeletal Function: A Review of the Molecular and Clinical Studies

Vitamin D Status and Cardiovascular Risk Factors in Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Study in a Tertiary-Level Hospital in Antananarivo, Madagascar

Background

Diabetes mellitus is already a major cardiovascular risk factor (CRF). Hypovitaminosis D is common in patients with type 2 diabetes mellitus (T2DM). It also increases the cardiovascular risk of these subjects.

Objective

To determine the vitamin D status of Malagasy with T2DM seen at the Soavinandriana Hospital Center, and the association between hypovitaminosis D and CRF.

Methods

This was a cross-sectional study, carried out over a period of 2 years. Assayed by the chemiluminescence technique, vitamin D was "normal", "insufficient" and "deficient" if the 25-hydroxyvitamin D plasma was ≥30 ng/mL, 20-29 ng/mL and ≤19 ng/mL, respectively. Hypovitaminosis D was the set of vitamin D insufficiency and deficiency.

Results

Among the 318 T2DM, the prevalence of hypovitaminosis D was 66.0% (45.2% insufficiency and 20.8% deficiency). Their factors associated were age ≥70 years (OR = 2.15 [1.26-3.66]), glycated haemoglobin ≥7% (4.97 [2.97-8.39]), and retinopathy (OR = 4.15 [1.85-9.32]). After adjustment for age, Hb A1c ≥7% and retinopathy, hypovitaminosis D was associated with hypertension (OR = 8.77 [4.76-16.2]), dyslipidaemia (OR = 8.05 [3.98-14.5]), ex-smoking (OR = 6.07 [2.78-13.3]), microalbuminuria (OR = 2.95 [1.25-6.97]) and carotid atherosclerosis (OR = 2.96 [1.83-4.35]).

Conclusion

Hypovitaminosis D was common in T2DM. Its treatment is primarily preventive. It is also important to control associated CRF, diabetes and its complications.

Emerging perspectives: unraveling the anticancer potential of vitamin D3

Vitamin D3, a fat-soluble vitamin known for its critical function in calcium homeostasis and bone health, is gaining interest for its anticancer properties. Observational studies have suggested a negative relationship between vitamin D levels and the incidence of some malignancies throughout the years, prompting substantial investigation to find its anticancer effects. The purpose of this comprehensive review is to investigate the diverse function of vitamin D3 in cancer prevention and therapy. We explored the molecular mechanism underlying its effects on cancer cells, which range from cell cycle control and death to angiogenesis and immune response modulation. Insights from in vitro and in vivo studies provide valuable evidence supporting its anticancer potential. Furthermore, we look at epidemiological and clinical studies that investigate the relationship between vitamin D3 levels and cancer risk or treatment results. Vitamin D3 supplementation's safety profile and cost-effectiveness increase its attractiveness as an adjuvant therapy in conjunction with traditional treatment regimens. Our critical review of the current literature provides an in-depth understanding of vitamin D3's anticancer effect, covering the obstacles and possibilities in realizing its promise for cancer prevention and therapy. The findings of this study might pave the way for the development of innovative treatment techniques that take use of the advantages of vitamin D3 to fight cancer and improve patient care. As research progresses, a better understanding of vitamin D3's anticancer processes will surely simplify its incorporation into personalized cancer care techniques, hence enhancing patient outcomes in the battle against cancer.

Interaction between Fokl polymorphism and vitamin D deficiency in the symptoms of mental disorders in adults: a population-based study

Mental disorders are intricate and multifaceted and encompass social, economic, environmental, and biological factors. This study aimed to explore the potential association between vitamin D deficiency and anxiety and depression symptoms in adults, considering the role of the vitamin D receptor gene polymorphism FokI (rs2228570). This was a population-based cross-sectional study with stratified and cluster sampling, evaluating anxiety symptoms (AS) and depression symptoms (DS) in 1637 adults. Vitamin D levels were measured using electrochemiluminescence and were considered deficient when < 20 ng/mL in a healthy population or < 30 ng/mL in at-risk groups. Genotyping was performed using real-time polymerase chain reaction with TaqMan probes. The prevalence rates of AS, DS, and vitamin D deficiency were 23.5%, 15.8%, and 30.9%, respectively. No direct association was observed between vitamin D deficiency and AS or DS. However, interaction analysis revealed a combined effect of vitamin D deficiency and FokI for DS but not for AS. Individuals with vitamin deficiency and one or two copies of the altered allele of the FokI exhibited a higher prevalence of DS than individuals homozygous for the wild-type allele and vitamin D sufficiency. The interaction between vitamin D deficiency and the FokI polymorphism was associated with DS.

Ethnic-Based Assessment of Vitamin D and Magnesium Status in the Kingdom of Bahrain

BACKGROUND

Vitamin D deficiency is a major global health problem. Most previous studies focused attention on the significant role of sunlight exposure in the homeostasis of vitamin D and calcium blood levels. Magnesium is pivotal in the proper functioning of vitamin D, and the physiologic functions of different organs require a balanced vitamin D and magnesium status. The relationship between sunlight exposure and blood levels of vitamin D and magnesium has often been overlooked. The aim of this study was to evaluate vitamin D and magnesium status based on sunlight exposure and ethnicity in Bahraini and expatriate workers.

METHODS

A cross-sectional study was conducted between October 2018 and September 2019. One hundred and seventy-four subjects participated in this study were subdivided based on their ethnicity and work environment-dependent exposure to sunlight into four groups: (1) Bahraini exposed (n=94), (2) Bahraini non-exposed (n=25), (3) expatriate exposed (n=31), and (4) expatriate non-exposed (n=24). Blood levels of vitamin D and magnesium were evaluated for all the participants.

RESULTS

 Independent of ethnicity, vitamin D levels were insignificantly different among the studied groups and were all below the normal reference range. Yet, there was still a sunlight-dependent increase in vitamin D level that could be seen only in Bahraini workers. Magnesium levels were significantly higher in expatriates when compared to Bahraini workers. Sunlight-exposed expatriates had significantly higher magnesium levels than their Bahraini counterparts, while there was no significant difference between both ethnicities in the non-exposed groups.

CONCLUSION

Country- and ethnic-specific definitions for vitamin D status and sunlight exposure are recommended. The assessment of magnesium status is pivotal in the overall assessment of vitamin D status.

Exploring Promising Therapies for Non-Alcoholic Fatty Liver Disease: A ClinicalTrials.gov Analysis

Background

Non-alcoholic fatty liver disease (NAFLD) is a common disease and has been increasing in recent years. To date, no FDA-approved drug specifically targets NAFLD.

Methods

The terms "Non-alcoholic Fatty Liver Disease" and "NAFLD" were used in a search of ClinicalTrials.gov on August 24, 2023. Two evaluators independently examined the trials using predetermined eligibility criteria. Studies had to be interventional, NAFLD focused, in Phase IV, and completed to be eligible for this review.

Results

The ClinicalTrials.gov database was searched for trials examining pharmacotherapeutics in NAFLD. The search revealed 1364 trials, with 31 meeting the inclusion criteria. Out of these, 19 were finalized for evaluation. The dominant intervention model was Parallel. The most prevalent studies were in Korea (26.3%) and China (21.1%). The most common intervention was metformin (12.1%), with others like Exenatide and Pioglitazone accounting for 9.1%.

Conclusion

Therapeutics used to manage NAFLD are limited. However, various medications offer potential benefits. Further investigations are definitely warranted.

Effect of Oral Consumption of Vitamin D on Uterine Fibroids: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Impaired vitamin D status is highly prevalent among women with UFs. The objective of this first-ever systematic review and meta-analysis was to summarize the effect of vitamin D supplementation on the size of uterine fibroids (UFs). We performed a comprehensive literature search for published randomized controlled trials (RCTs) in Medline, Scopus, Web of Science, and Cochrane Central Register of Controlled Trials from inception to September 2022. Five trials including 511 participants (256 cases and 255 controls) were included. Pooling results from five trials, which compared size of UFs between experimental and placebo groups, revealed that vitamin D supplementation could significantly decrease the size of UFs (standardized mean difference [SMD]: -0.48, 95% confidence interval [CI]: -0.66, -0.31) and cause improvement in serum level of vitamin D compared to placebo group (SMD: 3.1, 95% CI: 0.66, 5.55). A significant effect was observed in the subset of trials administering vitamin D supplementation for >8 wk (SMD: -0.62, 95% CI: -0.88, -0.37). In conclusion, vitamin D supplementation significantly increases serum levels of vitamin D and reduces the size of UFs. However, larger, well-designed RCTs are still needed to determine the effect of vitamin D on other parameters of UFs.

Vitamin D and cancer

The role of vitamin D in the prevention of chronic diseases including cancer, has received a great deal of attention during the past few decades. The term "Cancer" represents multiple disease states with varying biological complexities. The strongest link between vitamin D and cancer is provided by ecological and studies like observational, in preclinical models. It is apparent that vitamin D exerts diverse biological responses in a tissue specific manner. Moreover, several human factors could affect bioactivity of vitamin D. The mechanism(s) underlying vitamin D initiated anti-carcinogenic effects are diverse and includes changes at the muti-system levels. The oncogenic environment could easily corrupt the traditional role of vitamin D or could ensure resistance to vitamin D mediated responses. Several researchers have identified gaps in our knowledge pertaining to the role of vitamin D in cancer. Further areas are identified to solidify the role of vitamin D in cancer control strategies.

Host Genetic Impact on Infectious Diseases among Different Ethnic Groups

Infectious diseases such as malaria, tuberculosis (TB), human immunodeficiency virus (HIV), and the coronavirus disease of 2019 (COVID-19) are problematic globally, with high prevalence particularly in Africa, attributing to most of the death rates. There have been immense efforts toward developing effective preventative and therapeutic strategies for these pathogens globally, however, some remain uncured. Disease susceptibility and progression for malaria, TB, HIV, and COVID-19 vary among individuals and are attributed to precautionary measures, environment, host, and pathogen genetics. While studying individuals with similar attributes, it is suggested that host genetics contributes to most of an individual's susceptibility to disease. Several host genes are identified to associate with these pathogens. Interestingly, many of these genes and polymorphisms are common across diseases. This paper analyzes genes and genetic variations within host genes associated with HIV, TB, malaria, and COVID-19 among different ethnic groups. The differences in host-pathogen interaction among these groups, particularly of Caucasian and African descent, and which gene polymorphisms are prevalent in an African population that possesses protection or risk to disease are reviewed. The information in this review could potentially help develop personalized treatment that could effectively combat the high disease burden in Africa.

Vitamin D and depression in older adults: lessons learned from observational and clinical studies

Depression is a mental disorder triggered by the interaction of social, psychological and biological factors that have an important impact on an individual's life. Despite being a well-studied disease with several established forms of treatment, its prevalence is increasing, especially among older adults. New forms of treatment and prevention are encouraged, and some researchers have been discussing the effects of vitamin D (VitD) on depression; however, the exact mechanism by which VitD exerts its effects is not yet conclusive. In this study, we aimed to discuss the possible mechanisms underlying the association between VitD and depression in older adults. Therefore, we conducted a systematic search of databases for indexed articles published until 30 April 2021. The primary focus was on both observational studies documenting the association between VitD and depression/depressive symptoms, and clinical trials documenting the effects of VitD supplementation on depression/depressive symptoms, especially in older adults. Based on pre-clinical, clinical and observational studies, it is suggested that the maintenance of adequate VitD concentrations is an important issue, especially in older adults, which are a risk population for both VitD deficiency and depression. Nevertheless, it is necessary to carry out more studies using longitudinal approaches in low- and middle-income countries to develop a strong source of evidence to formulate guidelines and interventions.

Effect of Nutrition Education on Health Science University Students to Improve Cardiometabolic Profile and Inflammatory Status

The inadequate lifestyle associated with university life may have a negative impact on various cardiometabolic factors. The aim of this study was to evaluate the effect of a one-year nutrition education course on cardiometabolic parameters in undergraduate health science students. During the 2021-22 academic year, 1.30 h nutrition sessions were conducted twice a week. Capillary blood samples were collected and centrifuged to measure cardiometabolic and inflammatory biomarkers in serum. The sample studied consisted of 49 students: 20.4% male and 79.6% female. The nutritional intervention resulted in changes in dietary patterns, with increased consumption of vegetables, nuts and legumes. After the course, females showed an increase in HDL-cholesterol levels (p = 0.007) and no change in LDL-cholesterol levels (p = 0.189). On the other hand, males showed significant changes in HDL-cholesterol (p = 0.001) and LDL-cholesterol (p = 0.043) levels. The atherogenic index was also significantly reduced (p < 0.001) in both males (p = 0.009) and females (p = 0.002). Differences were also observed in the increase in vitamin D levels in both males and females, although the magnitude of the increase was greater in the men (Δ = 7.94, p = 0.016 in men vs. Δ = 4.96, p = 0.001 in women). The monocyte-to-HDL ratio (MHR) showed a significant reduction, although these differences were only significant in males. Students with low vitamin D levels had higher LDL-cholesterol values (p = 0.01) and atherogenic index (p = 0.029). Adjusted linear regression analysis showed a significant association between post-course vitamin D MHR (β = -0.42, IC: -0.29, -0.06, p < 0.01). These findings suggest the importance of including nutrition education programs during the university stage for the prevention of long-term health problems.

The Role of Vitamin D and Its Molecular Bases in Insulin Resistance, Diabetes, Metabolic Syndrome, and Cardiovascular Disease: State of the Art

In the last decade, an increasing awareness was directed to the role of Vitamin D in non-skeletal and preventive roles for chronic diseases. Vitamin D is an essential hormone in regulating calcium/phosphorous balance and in the pathogenesis of inflammation, insulin resistance, and obesity. The main forms of vitamin D, Cholecalciferol (Vitamin D3) and Ergocalciferol (Vitamin D2) are converted into the active form (1,25-dihydroxyvitamin D) thanks to two hydroxylations in the liver, kidney, pancreas, and immune cells. Some anti-inflammatory cytokines are produced at higher levels by vitamin D, while some pro-inflammatory cytokines are released at lower levels. Toll-Like Receptor (TLR) expression is increased, and a pro-inflammatory state is also linked to low levels of vitamin D. Regardless of how it affects inflammation, various pathways suggest that vitamin D directly improves insulin sensitivity and secretion. The level of vitamin D in the body may change the ratio of pro- to anti-inflammatory cytokines, which would impact insulin action, lipid metabolism, and the development and function of adipose tissue. Many studies have demonstrated an inverse relationship between vitamin D concentrations and pro-inflammatory markers, insulin resistance, glucose intolerance, metabolic syndrome, obesity, and cardiovascular disease. It is interesting to note that several long-term studies also revealed an inverse correlation between vitamin D levels and the occurrence of diabetes mellitus. Vitamin D supplementation in people has controversial effects. While some studies demonstrated improvements in insulin sensitivity, glucose, and lipid metabolism, others revealed no significant effect on glycemic homeostasis and inflammation. This review aims to provide insight into the molecular basis of the relationship between vitamin D, insulin resistance, metabolic syndrome, type 1 and 2 diabetes, gestational diabetes, and cardiovascular diseases.

Machine learning approach for the detection of vitamin D level: a comparative study

BACKGROUND

After the World Health Organization declared the COVID-19 pandemic, the role of Vitamin D has become even more critical for people worldwide. The most accurate way to define vitamin D level is 25-hydroxy vitamin D(25-OH-D) blood test. However, this blood test is not always feasible. Most data sets used in health science research usually contain highly correlated features, which is referred to as multicollinearity problem. This problem can lead to misleading results and overfitting problems in the ML training process. Therefore, the proposed study aims to determine a clinically acceptable ML model for the detection of the vitamin D status of the North Cyprus adult participants accurately, without the need to determine 25-OH-D level, taking into account the multicollinearity problem.

METHOD

The study was conducted with 481 observations who applied voluntarily to Internal Medicine Department at NEU Hospital. The classification performance of four conventional supervised ML models, namely, Ordinal logistic regression(OLR), Elastic-net ordinal regression(ENOR), Support Vector Machine(SVM), and Random Forest (RF) was compared. The comparative analysis is performed regarding the model's sensitivity to the participant's metabolic syndrome(MtS)'positive status, hyper-parameter tuning, sensitivities to the size of training data, and the classification performance of the models.

RESULTS

Due to the presence of multicollinearity, the findings showed that the performance of the SVM(RBF) is obviously negatively affected when the test is examined. Moreover, it can be obviously detected that RF is more robust than other models when the variations in the size of training data are examined. This experiment's result showed that the selected RF and ENOR showed better performances than the other two models when the size of training samples was reduced. Since the multicollinearity is more severe in the small samples, it can be concluded that RF and ENOR are not affected by the presence of the multicollinearity problem. The comparative analysis revealed that the RF classifier performed better and was more robust than the other proposed models in terms of accuracy (0.94), specificity (0.96), sensitivity or recall (0.94), precision (0.95), F1-score (0.95), and Cohen's kappa (0.90).

CONCLUSION

It is evident that the RF achieved better than the SVM(RBF), ENOR, and OLR. These comparison findings will be applied to develop a Vitamin D level intelligent detection system for being used in routine clinical, biochemical tests, and lifestyle characteristics of individuals to decrease the cost and time of vitamin D level detection.

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.

Does Decreased Vitamin D Level Trigger Bipolar Manic Attacks?

BACKGROUND

Bipolar disorder is a chronic psychiatric disorder with depression and manic episodes. It is one of the leading causes of disease-related disability worldwide. Despite the presence of various alternative drug options for bipolar disorder, some patients do not adequately benefit from the treatment. Therefore, possible underlying mechanisms need to be clarified. Recently, studies on the relationship between bipolar disorder and vitamin D (Vit D) have attracted attention. Although many studies have found an association between depression and Vit D deficiency, little is known about the relationship between manic episodes and Vit D. The aim of this study was to compare Vit D and related metabolites of bipolar manic episodes prior to treatment, bipolar remission after treatment, and healthy control groups.

METHODS

This case-control study consisted of 34 bipolar manic episode patients and 34 healthy controls. Disease activity was evaluated with the Hamilton Depression Rating Scale (HAM-D) and Young Mania Rating Scale (YMRS). Firstly, serum 25-hydroxy vitamin D (25-OHD), calcium (Ca) and phosphorus (P) levels of patients in the bipolar manic episode were measured and compared with healthy control. Secondly, serum 25-OHD, Ca and P levels in the euthymic periods of the same patients were measured and compared with healthy control.

RESULTS

Bipolar manic episode Vit D levels were lower when compared to healthy controls; while there was no difference in terms of Ca and P levels. There was no significant difference between the bipolar euthymic period patients and the healthy control group in terms of 25-OHD, Ca and P levels.

CONCLUSION

Our results demonstrated low serum Vit D concentrations in the acute manic episode of bipolar disorder. Decreased Vit D level may play a role in the onset of the manic episode, or malnutrition and insufficient sunlight during the manic episode may have caused Vit D deficiency. Future studies are needed to exclude potential confounding factors and to compare all mood episodes.

The Association between Vitamin D, Interleukin-4, and Interleukin-10 Levels and CD23+ Expression with Bronchial Asthma in Stunted Children

Children with stunted growth have an increased risk of wheezing, and studies have shown that low levels of vitamin D and interleukin (IL)-10, along with increased IL-4 levels and CD23+ expression, are present in stunted and asthmatic children. To date, it is not known whether these factors are related to the incidence of asthma in stunted children. This case-control study investigated the association between vitamin D, IL-4, and IL-10 levels and CD23+ expression with bronchial asthma in stunted children. The study included 99 children aged 24-59 months, i.e., 37 stunted-sthmatic children (cases), 38 stunted children without asthma, and 24 non-stunted children with asthma. All children were tested for their 25(OH)D levels using chemiluminescent immunoassay (CLIA), IL-4 and IL-10 levels were measured through enzyme-linked immunosorbent assay (ELISA) testing, and CD23+ expression was measured through flow cytometry bead testing. The data were analyzed using chi-squared, Kruskal-Wallis, and Mann-Whitney tests. The results showed that stunted asthmatic children had a higher incidence of atopic family members than those without asthma. Additionally, stunted asthmatic children had a higher prevalence of vitamin D deficiency (48.6%) than the control group (44.7% and 20.8%). Furthermore, stunted asthmatic children had significantly lower levels of 25(OH)D [20.55 (16.18-25.55), p = 0.042] and higher levels of IL-4 [1.41 (0.95-2.40), p = 0.038], although there were no significant differences in IL-10 levels and CD23+ expression. The study concluded that low vitamin D and high IL-4 levels are associated with bronchial asthma in stunted children, while IL-10 and CD23+ do not show a significant association.

Correlation of CYP2R1 gene promoter methylation with circulating vitamin D levels among healthy adults

Background & objectives

Despite being a tropical country, vitamin D deficiency is highly prevalent in India with studies indicating 40-99 per cent prevalence. Apart from calcium and phosphate metabolism, vitamin D is involved in cell cycle regulation, cardiovascular, hepatoprotection. The metabolism of vitamin D is regulated by vitamin D tool genes (CYP2R1/CYP27B1/CYP24A1/VDR). The promoter regions of some of these genes have CpG islands, making them prone to methylation induced gene silencing, which may cause a reduction in circulating vitamin D levels. Epigenetic basis of vitamin D deficiency is yet to be studied in India, and hence, this pilot study was aimed to analyze whether methylation levels of CYP2R1 gene were correlated with the levels of 25(OH)D in healthy, adult individuals in Indian population.

Methods

In this cross-sectional study, healthy adults of 18-45 yr of age with no history of malabsorption, thyroidectomy, chronic illness or therapeutic vitamin D supplementation were recruited. DNA methylation analysis was carried out by methylation specific quantitative PCR. Serum calcium, phosphate and vitamin D levels were also quantified. Statistical analysis was done by R 4.0.5 software.

Results

A total of 61 apparently healthy adults were analyzed. The serum vitamin D levels did not correlate with CYP2R1 methylation levels in our study population. Significant positive correlation was observed between age and serum vitamin D levels. Significant association of gender was found with CYP2R1 methylation levels.

Interpretation & conclusions

This study found no significant correlation between levels of CYP2R1 methylation and circulating 25(OH)D deficiency. Further studies on the Indian population having a larger sample size including entire vitamin D tool genes, among different ethnic groups may be conducted to elucidate molecular etiology of circulating 25(OH)D deficiency. The high prevalence of normal serum calcium and phosphate levels among vitamin D deficient subjects in this study coupled with the strikingly high prevalence of the deficiency at the national level, may suggest the need to revise the cut-off criteria for vitamin D deficiency in the Indian population.

The Global Prevalence of Vitamin D Deficiency and Insufficiency in Patients with Multiple Myeloma: A Systematic Review and Meta-Analysis

BACKGROUND

Multiple myeloma (MM) is a hematological malignancy characterized by the exponential growth of malignant plasma cells. Individuals diagnosed with MM exhibit a deficiency in vitamin D and may suffer fatigue, a loss of muscular strength, persistent musculoskeletal aches, and pain. The objective of this systematic review and meta-analysis is to determine the prevalence of vitamin D insufficiency and deficiency in individuals diagnosed with MM.

METHODS

We searched five electronic databases using relevant keywords. The quality of the included studies was evaluated using the critical appraisal tool developed by the Joanna Briggs Institute. We employed a random-effects model and presented the findings in the form of percentages accompanied by 95% confidence intervals (CI). This protocol has been officially registered in PROSPERO under the registration number CRD42021248710.

RESULTS

The meta-analysis comprised a total of eighteen studies and found that, among patients with MM, the occurrence of serum vitamin D deficiency and insufficiency was 39.4% (95% CI: 25.8 to 52.9, n = 3746) and 34.1% (95% CI: 20.9 to 47.2, n = 3559), respectively. The findings indicate that a greater proportion of newly diagnosed patients exhibited vitamin D deficiency and insufficiency, with rates of 43.0% and 41.6%, respectively, compared to those receiving treatment (rates of 41.6% and 32.3%, respectively). The findings of the sensitivity analyses were consistent, and most of the studies (72.2%) were deemed to be of high quality. The results of Egger's test indicated the absence of publication bias.

CONCLUSIONS

Patients diagnosed with MM have been found to exhibit significantly elevated levels of both vitamin D deficiency and insufficiency. Therefore, it is recommended to consider vitamin D testing as an additional parameter in the current criteria for the clinical evaluation of MM.

Exploring the Role of Vitamin D in Atherosclerosis and Its Impact on Cardiovascular Events: A Comprehensive Review

This review explores the role of vitamin D in atherosclerosis and its impact on cardiovascular events. Atherosclerosis, a chronic inflammatory disease characterized by plaque accumulation in arterial walls, is a major contributor to cardiovascular events such as heart attacks and strokes. Vitamin D has emerged as a multifunctional hormone with pleiotropic effects, extending beyond its traditional role in calcium and bone metabolism. Through its anti-inflammatory, immunomodulatory, and antioxidative properties, vitamin D may influence the development and progression of atherosclerosis. The association between vitamin D deficiency and atherosclerosis has been extensively studied. Observational studies consistently report an inverse relationship between vitamin D levels, atherosclerotic risk factors, and markers of subclinical atherosclerosis. Mechanistically, vitamin D exerts anti-inflammatory effects, modulates immune responses, improves endothelial function, and influences lipid metabolism, all of which play critical roles in atherosclerosis development and plaque stability. Furthermore, vitamin D deficiency has been linked to an increased risk of cardiovascular events. Vitamin D influences thrombosis, platelet aggregation, arterial stiffness, blood pressure regulation, and overall vascular health, collectively contributing to cardiovascular event risk. However, the clinical implications of vitamin D for managing atherosclerosis and reducing cardiovascular event risk are still being explored. Randomized controlled trials investigating the cardiovascular benefits of vitamin D supplementation have yielded mixed results, necessitating further research to determine optimal dosages, durations, and patient populations. The review also addresses public health recommendations and future directions. Examining current guidelines, identifying research gaps, and considering public health implications are crucial for translating scientific knowledge into effective interventions. Raising awareness, implementing population-level strategies, and integrating vitamin D assessment into routine clinical practice are key to improving cardiovascular outcomes.

Association of amino acids and parameters of bone metabolism with endothelial dysfunction and vasculopathic changes in limited systemic sclerosis

Objectives

Pathways contributing to endothelial dysfunction in patients with limited cutaneous systemic sclerosis (lcSSc) are largely unknown. The aim of this study was to investigate potential associations of amino acids and parameters of bone metabolism with endothelial dysfunction and vasculopathy-related changes in patients with lcSSc and early-stage vasculopathy.

Methods

Amino acids, calciotropic parameters, including 25-hydroxyvitamin D and parathyroid hormone (PTH), and bone turnover parameters, including osteocalcin and N-terminal peptide of procollagen-3 (P3NP), were measured in 38 lcSSc patients and 38 controls. Endothelial dysfunction was assessed by biochemical parameters, pulse-wave analysis, flow-mediated and nitroglycerine-mediated dilation. Additionally, vasculopathy-related and SSc-specific clinical changes including capillaroscopic, skin, renal, pulmonary, gastrointestinal and periodontal parameters were recorded.

Results

No significant differences in amino acids, calciotropic and bone turnover parameters were observed between lcSSc patients and controls. In patients with lcSSc, several significant correlations were found between selected amino acids, parameters of endothelial dysfunction, vasculopathy-related and SSc-specific clinical changes (all with p < 0.05). In addition, significant correlations were observed between PTH and 25-hydroxyvitamin D with homoarginine, and between osteocalcin, PTH and P3NP with modified Rodnan skin score and selected periodontal parameters (all with p < 0.05). Vitamin D deficiency defined as 25-hydroxyvitamin D < 20 ng/ml was associated with the presence of puffy finger (p = 0.046) and early pattern (p = 0.040).

Conclusion

Selected amino acids may affect endothelial function and may be associated to vasculopathy-related and clinical changes in lcSSc patients, while the association with parameters of bone metabolism seems to be minor.

Differential expression of genes influencing mitotic processes in cord blood mononuclear cells after a pre-conceptional micronutrient-based randomised controlled trial: Pune Rural Intervention in Young Adolescents (PRIYA)

In The Pune Maternal Nutrition Study, vitamin B12 deficiency was seen in 65% of pregnant women, folate deficiency was rare. Maternal total homocysteine concentrations were inversely associated with offspring birthweight, and low vitamin B12 and high folate concentrations predicted higher offspring adiposity and insulin resistance. These findings guided a nested pre-conceptional randomised controlled trial 'Pune Rural Intervention in Young Adolescents'. The interventions included: (1) vitamin B12+multi-micronutrients as per the United Nations International Multiple Micronutrient Antenatal Preparation, and proteins (B12+MMN), (2) vitamin B12 (B12 alone), and (3) placebo. Intervention improved maternal pre-conceptional and in-pregnancy micronutrient nutrition. Gene expression analysis in cord blood mononuclear cells in 88 pregnancies revealed 75 differentially expressed genes between the B12+MMN and placebo groups. The enriched biological processes included G2/M phase transition, chromosome segregation, and nuclear division. Enriched pathways included, mitotic spindle checkpoint and DNA damage response while enriched human phenotypes were sloping forehead and decreased head circumference. Fructose-bisphosphatase 2 (FBP2) and Cell Division Cycle Associated 2 (CDCA2) genes were under-expressed in the B12 alone group. The latter, involved in chromosome segregation was under-expressed in both intervention groups. Based on the role of B-complex vitamins in the synthesis of nucleotides and S-adenosyl methionine, and the roles of vitamins A and D on gene expression, we propose that the multi-micronutrient intervention epigenetically affected cell cycle dynamics. Neonates in the B12+MMN group had the highest ponderal index. Follow-up studies will reveal if the intervention and the altered biological processes influence offspring diabesity.

The Vitamin D Serum Levels in Pregnant Women Affected by COVID-19: A Systematic Review and Meta-Analysis

Vitamin D can modulate immune responses, and its deficiency is linked to increased autoimmunity and susceptibility to infection. In the general population, it has been observed that serum vitamin D levels are connected with the risk of COVID-19 and its severity. Our study aims to examine reported findings on the effect of vitamin D serum levels on infection of COVID-19 during pregnancy. PubMed, Web of Science, Embase, and Cochrane Library were searched for relevant studies. Serum vitamin D serum levels in COVID-19-positive and COVID-19-negative pregnant women were 24.61 ± 20.86 ng/mL and 24.12 ± 17.33 ng/mL, respectively. In mild vs. moderate to critical COVID-19 pregnant women, vitamin D serum levels were 16.71 ± 9.04 ng/mL vs. 10.7 ± 9.37 ng/mL and severe vs. non-severe were 13.21 ± 11.47 ng/mL vs. 15.76 ± 10.0 ng/mL. Only one study reported vitamin D serum levels in the placenta of COVID-19-positive pregnant women compared with the control and results varied and amounted to 14.06 ± 0.51 ng/mL vs. 12.45 ± 0.58 ng/mL, respectively. Vitamin D deficiency tends to be common in pregnant women who have COVID-19, and the level of this vitamin has been demonstrated to have a strong correlation with the severity of the illness. As vitamin D serum levels correlate with COVID-19 symptoms and even with its occurrence, appropriate vitamin D supplementation in the prenatal period is suggested.

The Role of Vitamin D in Reducing the Risk of Metabolic Disturbances That Cause Cardiovascular Diseases

Among the most common problems facing public health today is a lack of vitamin D, which plays a role in the physiological processes of chronic illness conditions. Vitamin D deficiency in metabolic disorders has primary effects on osteoporosis, obesity, hypertension, diabetes, and cardiovascular disease (CVD). Vitamin D acts as a "co-hormone" in the various tissues of the body, and it has been found that vitamin D receptors (VDR) are present on all cell types, suggesting that vitamin D has a wide range of effects on most cells. Recently, there has been a surge in interest in assessing its roles. Vitamin D insufficiency increases the risk of diabetes because it lowers insulin sensitivity, and also raises the risk of obesity and CVD because of its effect on the body's lipid profile, particularly in terms of the prevalence of dangerously high levels of low-density lipoproteins (LDL). Furthermore, vitamin D insufficiency is often related to CVD and connected risk factors, highlighting the need to know vitamin D's functions in relation to metabolic syndrome and related processes. Through looking at previous studies, this paper explains why vitamin D is important, how deficiency is related to risk factors for metabolic syndrome through different mechanisms, and how deficiency affects CVD.

A Systematic Review Assessing the Impact of Vitamin D Levels on Adult Patients with Lymphoid Malignancies

Vitamin D deficiency has been correlated with various conditions, including the risk of developing lymphoid malignancies. This systematic review aimed to assess the association between vitamin D levels at diagnosis of lymphoid malignancies, patient outcomes, and survival. A systematic review was conducted, encompassing 15 studies published until January 2023, involving 4503 patients, examining the relationship between vitamin D and lymphoid cancers. The median age of the patients was 56.5 years, with a median follow-up duration of approximately 36 months across studies. The overall median vitamin D level at initial measurement was 20.4 ng/mL, while a <20 ng/mL threshold was used to define vitamin D insufficiency. The results demonstrated significant associations between vitamin D levels and patient outcomes in several lymphoid malignancies, with a pooled risk in disease progression of 1.93 and a pooled hazard ratio of 2.06 for overall survival in patients with 25-(OH)D levels below the normal threshold of 20 ng/mL. Among findings, it was demonstrated that supplemental vitamin D improves the chemosensitivity of tumors by reducing the rate of tumor growth compared with vitamin D or chemotherapy alone. Vitamin D had a protective effect for patients with DLBCL under R-CHOP treatment, while vitamin D insufficiency was associated with the impairment of rituximab treatment and showed worse clinical outcomes in chimeric antigen receptor T-cell (CAR-T) recipients. Although one study found no association between vitamin D deficiency and the cause of death, most associated vitamin D insufficiency with early clinical failure and lower survival probability. In conclusion, his systematic review highlights the importance of vitamin D levels in the prognosis and survival of patients with lymphoid malignancies. Further research is needed to better understand the underlying mechanisms and explore the potential benefits of vitamin D supplementation in managing these cancers.

Vitamin D reduces pain and cartilage destruction in knee osteoarthritis animals through inhibiting the matrix metalloprotease (MMPs) expression

Aim of the study

In this study, we investigated the therapeutic potential of vitamin D (VITD) in OA Wistar rats induced by anterior cruciate ligament transection combined with medial meniscectomy (ACLT + MMx). In ACLT + MMx-induced OA rats, pain severity, cartilage destruction, inflammatory cytokines, and MMPs were all measured.

Materials and methods

ACLT + MMx methods were used to induce OA, and pain behavioral studies such as the weight bearing test and paw withdrawal test were performed while the knee width and body weights were also measured. Furthermore, Hematoxylin and Eosin (H&E) staining was used to determine knee histopathological studies, as well as OARSI scoring, cartilage thickness, cartilage width, and cartilage degradation scores. The enzyme-linked immunosorbent assay (ELISA) studies were used to check the serum levels of VITD, C-telopeptide of Type II collagen (CTX-II), and pro-inflammatory cytokines tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and anti-inflammatory cytokines interleukin-10 (IL-10), and MMPs (MMP-3, MMP-9, and MMP-13). Finally, the reverse transcription polymerase chain reaction (RT-PCR) test was used to determine the levels of MMPs, nuclear factor-kappa B (NF-κB), TNF-α, IL-6, and IL-10 in IL-1β stimulated chondrocytes.

Results

The oral VITD supplement significantly reduced OA pain, inflammation, cartilage destruction, and MMPs levels. Furthermore, serum VITD levels increased while CTX-II levels decreased, indicating that VITD reduced cartilage degradation effectively. Moreover, VITD supplementation reduced the expression of pro-inflammatory TNF-α, IL-1β, and IL-6 cytokines while increasing the expression of anti-inflammatory IL-10. The elevation of MMPs after ACLT + MMx surgery contributed to articular cartilage destruction, which was reduced by VITD supplementation. Finally, VITD supplementation significantly reduces serum levels of MMPs, IL-1β, TNF-α, and IL-6 while increasing IL-10 levels. Then, using the in-vitro cytotoxicity (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) MTT assay, examine the cytotoxicity profile of VITD in rat chondrocytes after stimulated with IL-1β, which shows no toxicity in the dose range of VITD 0-500 IU. Finally, RT-PCR studies in IL-1β stimulated rat chondrocytes revealed that VITD (50, 100, and 500 IU) significantly reduced the mRNA levels of MMPs, NF-κB, TNF-α, and IL-6, while increasing IL-10 levels, indicating that VITD reduced chondrocyte destruction and overcame harsh conditions in a dose-dependent manner.

Conclusion

Overall, the in vivo and in vitro findings show that VITD effectively reduces OA pain, inflammation, and chondrocyte destruction by lowering MMPs levels specifically.

Decreased Levels of Vitamin D in Bipolar Patients

Recently, vitamin D is considered a pleiotropic hormone, and as such, it has also become a topic of renewed interest in neuropsychiatry for its proposed role in the aetiology and pathophysiology of different psychiatric conditions, including mood disorders (MDs). This seems particularly crucial while considering the relatively high and often neglected prevalence of hypovitaminosis D in the general population and in specific groups, such as patients suffering from the most common type of MDs, which are major depression (MDD) and bipolar disorders (BDs). Therefore, in view of the controversial literature and findings on this topic and its potential therapeutic implications, the present study aimed at evaluating vitamin D levels in the plasma of a sample of inpatients fulfilling the DSM-5 criteria for mood episodes within BDs. The clinical picture was assessed by means of specific rating scales. The results showed that the vitamin D levels (mean ± SD, nM/L) of the bipolar patients of our sample were significantly lower (14.58 ± 11.27 nmol/L) than the normative values (>30 nmol/L). Eleven patients had sufficient values and only 4 had optimal, while 19 showed insufficient, 18 critical, and 17 severely critical levels. No differences emerged according to different socio-demographic or clinical features. In our opinion, the present findings strengthen previous research highlighting decreased vitamin D levels in bipolar patients and support the role of this pleiotropic hormone in BDs. Nevertheless, further studies should follow to corroborate the data of this preliminary study and to address the potential benefits of vitamin D supplementation in the treatment of MDs.

Very Low and High Levels of Vitamin D Are Associated with Shorter Leukocyte Telomere Length in 148,321 UK Biobank Participants

Background: Shorter leukocyte telomere length (LTL) is observed in multiple age-related diseases, which are also associated with vitamin D deficiency (i.e., osteosarcopenia, neurocognitive disorders, cancer, osteoarthritis, etc.), suggesting a close association between vitamin D and LTL. In this study, we examined the relationship between vitamin D levels and LTL in older participants of the UK Biobank. Methods: Data were collected from the UK Biobank. Participants aged 60 and older (n = 148,321) were included. Baseline LTL was measured using a multiplex qPCR technique and expressed as the ratio of the telomere amplification product (T) to that of a single-copy gene (S) (T/S ratio). Serum 25-hydroxyvitamin D (25OHD) was stratified by z score and linked to LTL in a linear regression model adjusting for covariates. Results: Compared to the medium level, a low (in the range of 16.6 nmol/L, 29.7 nmol/L) or extremely low (≤16.6 nmol/L) level of serum 25OHD was associated with shorter LTL: 0.018 SD (standardized β = −0.018, 95% CI −0.033 to −0.003, p = 0.022) and 0.048 SD (standardized β = −0.048, 95% CI −0.083 to −0.014, p = 0.006), respectively. Additionally, the high serum 25OHD groups (>95.9 nmol/L) had 0.038 SD (standardized β = −0.038, 95% CI −0.072 to −0.004, p = 0.030) shorter mean LTL than the group with medium 25OHD levels. The associations above were adjusted for multiple variables. Conclusions: In this population-based study, we identified an inverted U-shape relationship between LTL and vitamin D status. Our findings could be affected by unmeasured confounders. Whether high or low vitamin D-associated shorter LTL is mechanistically related to age-related conditions remains to be elucidated.

Vitamin D3 Supplementation: Comparison of 1000 IU and 2000 IU Dose in Healthy Individuals

Background: Scientific studies point to a significant global vitamin D deficiency. The recommended dose of vitamin D for the adult population in Central Europe is 800–2000 IU/day. The aim of our study was to determine whether doses of 1000 IU or 2000 IU of vitamin D3 are adequate to achieve the sufficiency reference values of [25(OH)D]. Methods: Seventy-two healthy volunteers, average age twenty-two, took part in the study. The study was conducted from October to March in order to eliminate intra-dermal vitamin D production. Vitamin D3 in an oleaginous mixture was used. The participants used either 1000 IU or 2000 IU/daily for two 60-day periods with a 30-day break. Results: The dose of 1000 IU, taken for 60 days, increased vitamin D levels relatively little. Furthermore, serum vitamin D levels decreased in the 30 days following the cessation of supplementation. Taking 2000 IU daily led to a sharp increase in serum levels which plateaued 30 days after the subjects stopped using vitamin D3 drops. Conclusions: Both doses, taken daily, can help maintain adequate vitamin D levels during the winter months. A daily dose of 2000 IU, however, maintained the desired levels of vitamin D for a longer period.

25-Hydroxycholecalciferol Inhibits Cell Growth and Induces Apoptosis in SiHa Cervical Cells via Autocrine Vitamin D Metabolism

Preclinical studies show that the anticancer actions of vitamin D metabolites are mediated by apoptosis, inhibition of cell proliferation and induction of cell cycle arrest. Cervical cancer cells express an autocrine vitamin D metabolising system (VDMS) comprised of a vitamin D receptor, vitamin D catabolic enzyme (CYP24A1), and the activating enzyme of 25-hydroxycholecalciferol (25(OH)D3), CYP27B1. We assessed the anticancer effects of 25(OH)D3 at clinically relevant concentrations on a cervical squamous cell cancer cell line, SiHa. We evaluated cell health parameters (cell count, viability, and cell cycle), cell death modes (apoptosis, autophagic-dependent death, and necrosis by flow cytometry and transmission electron microscopy), and autocrine VDMS gene and protein expression by qPCR and Western blot, respectively. Our study demonstrates that physiological and supraphysiological doses of 25(OH)D3 inhibit cell growth and viability and induce biochemical and morphological apoptosis in SiHa cells. These growth effects are mediated by alteration in the VDMS gene and protein expression, with prominent negative feedback at supraphysiological treatment dose. These data identify promising therapeutic potential of 25(OH)D3 in cervical cancer, which warrants further clinical translational investigations.

Vitamin D deficiency and C-reactive protein: a bidirectional Mendelian randomization study

BACKGROUND

Low vitamin D status is often associated with systemic low-grade inflammation as reflected by elevated C-reactive protein (CRP) levels. We investigated the causality and direction of the association between vitamin D status and CRP using linear and non-linear Mendelian randomization (MR) analyses.

METHODS

MR analyses were conducted using data from 294 970 unrelated participants of White-British ancestry from the UK Biobank. Serum 25-hydroxyvitamin D [25(OH)D] and CRP concentrations were instrumented using 35 and 46 genome-wide significant variants, respectively.

RESULTS

In non-linear MR analysis, genetically predicted serum 25(OH)D had an L-shaped association with serum CRP, where CRP levels decreased sharply with increasing 25(OH)D concentration for participants within the deficiency range (<25 nmol/L) and levelled off at ∼50 nmol/L of 25(OH)D (Pnon-linear = 1.49E-4). Analyses using several pleiotropy-robust methods provided consistent results in stratified MR analyses, confirming the inverse association between 25(OH)D and CRP in the deficiency range (P = 1.10E-05) but not with higher concentrations. Neither linear or non-linear MR analysis supported a causal effect of serum CRP level on 25(OH)D concentration (Plinear = 0.32 and Pnon-linear = 0.76).

CONCLUSION

The observed association between 25(OH)D and CRP is likely to be caused by vitamin D deficiency. Correction of low vitamin D status may reduce chronic inflammation.

Role of vitamin D in pathogenesis and severity of COVID-19 infection

Coronavirus disease (COVID-19) is an infectious disease caused by a new virus that causes respiratory illness. Older adults and individuals who have pre-existing chronic medical conditions are at higher risk for more serious complications from COVID-19. Hypovitaminosis D is attributed to the increased risk of lung injury and acute respiratory distress syndrome (ARDS) as well as diabetes, cardiovascular events and associated comorbidities, which are the main causes of severe clinical complications in COVID-19 patients. Considering the defensive role of vitamin D, mediated through modulation of the innate and adaptive immune system as well as inhibition of the Renin Angiotensin System (RAS), vitamin D supplementation might boost the immune system of COVID-19 patients and reduce severity of the disease in vitamin D deficient individuals.

Melanin levels in relation to vitamin D among first-generation immigrants from different ethnic groups and origins: A comparative national Canadian cross-sectional study

Introduction

Immigrants to Western countries tend to have darker skin than native-born populations. We examined the relationship between skin melanin and serum vitamin D (vitD) [S-25(OH)D] levels and explored whether melanin levels explained S-25(OH)D variations between immigrants and native-born Canadians. This study offers novel findings as no such study has been conducted.

Methods

We used a national cross-sectional population-based design with data from the Canadian Health Measures Survey (CHMS). Skin melanin levels among first-generation immigrants based on their ethnicity and origin/country of birth were compared with white and native-born populations. We assessed the association between S-25(OH)D and melanin after adjusting for independent variables related to S-25(OH)D, melanin level, and immigration status.

Results

Of 11,579 participants, 21.9% were immigrants aged 3-79 years (mean age 39.23 years). Compared with non-immigrants, immigrants had lower S-25(OH)D levels (mean: 51.23 vs. 62.72; 95% CI: 8.37, 14.62; P < 0.001) but higher melanin levels (mean [SE]: 17.08 [0.25] vs. 16.29 [0.29]; 95% CI: -1.29, -0.281; P = 0.004). Melanin did not differ by length of stay in Canada but was weakly positively correlated (r = 0.088, P < 0.001) with S-25(OH)D. Sex (male), age (≥18 years), summer/fall seasons, sunlight exposure, sunscreen non-use, smoking, and alcohol consumption were associated with higher melanin levels, whereas indoor tanning use was not.

Conclusion

Skin melanin levels were associated with sociodemographic and behavioral characteristics. Immigrants had higher melanin levels, but melanin did not differ by length of stay in Canada. The weak positive correlation between melanin and S-25(OH)D suggested confounding factors may impact the relationship between melanin levels, S-25(OH)D, and immigration status.

Vitamin D attenuates biofilm-associated infections via immunomodulation and cathelicidin expression: a narrative review

INTRODUCTION

Infections are becoming more difficult to treat, at least partly on account of microbes that produce biofilms. Reports suggest that decreased levels of antimicrobial peptides like cathelicidin, elevated levels of inflammatory cytokines, and biofilm formation are all associated with vitamin D deficiency, making vitamin D - deficient individuals more susceptible to infection. Infections attributable to biofilm-producing microbes can be managed by adjuvant therapy with vitamin D because of its immunomodulatory role, particularly because of the ability of vitamin D-pathway to induce the antimicrobial peptides like cathelicidin and decrease proinflammatory cytokines.

AREAS COVERED

This narrative review covers biofilm formation, infections associated with biofilm due to vitamin D deficiency, putative role of vitamin D in host protection and the effect of vitamin D supplementation in biofilm-associated infections. A comprehensive literature search in PubMed and Google Scholar utilizing suitable keywords at multiple time points extracted relevant articles.

EXPERT OPINION

Although vitamin D deficiency has been associated with infections by biofilm producing microbes, comprehensive clinical trials in various ethnicities are required to understand the likely relationships between vitamin D receptor gene expression, cathelicidin levels, and infection outcome. Current evidence hypothesizes that maintaining normal vitamin D level can help prevent and treat these infections.

Serum 25-hydroxyvitamin D deficiency is associated with atopy, and sex may be an effect modifier of its association with asthma in teenagers from northeast Brazil

OBJECTIVE

Sufficient vitamin D (25-hydroxyvitamin D [25(OH)D]) serum levels are associated with decreased asthma symptoms. Our aim was to investigate associations between vitamin D and atopy, asthma, asthma severity, and asthma phenotypes in Brazilian teenagers.

METHODS

This cross-sectional study involved 942 individuals (11-19 years old) engaged in an asthma cohort. The ISAAC questionnaire was employed to diagnosis asthma and asthma severity. Serum allergen-specific immunoglobulin E (sIgE) was measured by ImmunoCap and serum 25(OH)D was measured by ELISA. We calculated the correlation between sIgE and 25(OH)D. We used multivariate logistic regression analysis to assess associations of interest.

RESULTS

We found that 25(OH)D deficiency was positively associated with atopy (OR 1.45, confidence interval [CI] 1.05-2.00) and high levels of this vitamin negatively correlated with sIgE to Dermatophagoides pteronyssinus (r = -0.11, p = 0.019). The average 25(OH)D serum level was 27.0 ± 9.5 ng/ml; 366 individuals (38.8%) had a sufficient level. There was no association between 25(OH)D and asthma, asthma severity or asthma phenotypes in the population. However, sex was a possible effect modifier of the association between vitamin D and asthma: insufficiency in asthmatic women (86%) was higher than in asthmatic men (42%), and there was an association between insufficient vitamin D levels and greater asthma risk only in women (OR = 3.06, 95% CI 1.16-8.07).

CONCLUSION

We have shown that vitamin D deficiency was associated with greater risk of atopy in both sexes and vitamin D insufficiency was associated with asthma only in women. There was no association between vitamin D levels and asthma phenotypes or asthma severity.

Study on the relationship between vitamin D level and macrophage typing in patients with type 2 diabetes mellitus

Objective

Population studies have shown that vitamin D (VitD) deficiency is associated with an increased incidence of type 2 diabetes mellitus (T2DM), VitD deficiency is a potential risk factor for T2DM, and the proportion of M1-type macrophages and M2-type macrophages in T2DM patients is imbalanced. Another study reported that VitD can affect the differentiation of macrophages into M1 and M2 types. However, there is no definitive result about the correlation between plasma VitD levels and macrophage typing in patients with T2DM. Whether VitD affects the progression of T2DM by regulating the polarization type of macrophages and the specific regulatory mechanism is not very clear. Therefore, we carried out the following research.

Methods

We first used flow cytometry to detect the proportions of M1 and M2 macrophages in peripheral blood of T2DM patients with different VitD levels. Furthermore, we used ELISA to detect the inflammatory factors affecting macrophage differentiation in patients’ plasma, including IL-6 secreted by M1-type macrophages and TGF-β secreted by M2-type macrophages. Mononuclear cells were separated from human peripheral blood with immunomagnetic beads, cultured in vitro, and treated with different concentrations of VitD, and the ratio of differentiation into M1 and M2 macrophages was detected by flow cytometry.

Results

With the increase of serum 25(OH)D levels in patients with T2DM, the proportion of M1 and M2 macrophages in peripheral blood decreased, that is, the polarized phenotype of macrophages was more inclined to M2 type, while plasma IL-6 gradually decreased, and TGF-β gradually increased. In addition, VitD can promote the differentiation of CD14-positive monocytes cultured in vitro into M2 macrophages.

Conclusions

When the level of VitD in T2DM patients is low, there are more M1-type macrophages in peripheral blood, and when the level of VitD is increased, M2-type macrophages are increased. Changes in related inflammatory factors were also consistent. In vitro culture of monocytes further confirmed that VitD can promote the differentiation of macrophages to M2 type in T2DM patients.

The correlation between vitamin D and levels of IFN-γ, NF-κB, thyroid antibodies in down syndrome: study in Indonesian children

BACKGROUND AND AIM

Vitamin D (VD) reduces interferon-gamma (IFN-γ) production and prevents nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation, impacting the inhibition of the autoimmunity process such as autoimmune thyroiditis (AITD). Children with Down syndrome (DS) are reported to have a higher risk of autoimmunity and lower VD levels than non-DS. Therefore, this study aimed to evaluate VD levels in Indonesian DS children and their relationship with marker of AITD.

METHODS

This study was conducted on DS children at Dr Soetomo Hospital between February 2021-June 2022. Socio-demographic status, amount of milk, fish and meat consumption, and duration of sun exposure were obtained using a self-report questionnaire. Thyroid hormone (TSH and FT4), thyroid antibody (TPO-Ab and Tg-Ab), 25 (OH)D, IFN-γ, and NF-κB levels were measured using ELISA.

RESULTS

Of the 80 participants, 53.75% had sufficient (50.829±17.713 ng/ml) and 46.25% had non-sufficient (20.606±5.974 ng/ml) VD levels. Daily milk consumption, meat and fish consumption were risk factors contributing to VD levels in multivariate analysis [p=0.003, OR=1.007(1.003-1.012); p=0.004, OR=1.816(1.209- 2.728), respectively]. Participants with sufficient VD had significantly higher TPO-Ab (p=0.007) and Tg-Ab (p=0.016). Mean of VD levels were significantly negatively correlated with IFN-γ levels (r =-0.262, p=0.037) and positively correlated with TPO-Ab (r= 0.432, p=1x10-5,) and Tg-Ab (r= 0.375, p=0.001).

CONCLUSIONS

Majority of subjects had sufficient VD levels. VD suppresses IFN-g, but is unable to affect NF-κB levels, presumably causing high levels of TPO-Ab and Tg-Ab in sufficient VD patient.

Association between 25-OH Vitamin D Deficiency and COVID-19 Severity in Pregnant Women

Evidence from studies in the general population suggests an association between vitamin D insufficiency/deficiency and COVID-19 susceptibility and disease severity. The present study was performed on 165 third-trimester pregnant women at the time of delivery. Seventy-nine women tested negative for SARS-CoV-2. From 86 women testing positive, 32 were asymptomatic, 44 presented a mild form of the disease, and 10 experienced severe symptoms. Serum 25-OH vitamin D levels were measured on blood samples collected on admission. Low vitamin D levels were detected in symptomatic but not asymptomatic COVID-19 patients compared to healthy women (p = 0.0227). In addition, 20 (45.4%) pregnant women in the mild COVID-19 group and 6 (60%) in the severe group were vitamin D deficient (p = 0.030). On the other hand, lasso regression analysis showed that 25-OH vitamin D deficiency is an independent predictor of severe COVID-19 with an odds ratio (OR) of 5.81 (95% CI: 1.108-30.541; p = 0.037). These results show the relationship between vitamin D deficiency in pregnant women and the severity of COVID-19 infection and support the recommendation to supplement with vitamin D to avoid worse COVID-19 outcomes during pregnancy.

Vitamin D deficiency in low-birth-weight infants in Uganda; a cross sectional study

Background

Vitamin D deficiency affects 7–86% of infants globally and results in recurrent infections, impaired growth and nutritional rickets. Low-birth-weight infants in Uganda are at risk of vitamin D deficiency due to limited sunlight exposure and dependence on breastmilk. We aimed to determine the prevalence and factors associated with vitamin D deficiency among low-birth-weight infants aged 6 weeks to 6 months at Mulago national referral hospital in Uganda.

Methods

We conducted a cross-sectional study at Mulago Hospital between September 2016 and March 2017. We enrolled infants born with low birth weight between six weeks and six months whose mothers were available and willing to provide informed consent. Upon obtaining informed consent, we administered a structured questionnaire and performed a physical examination on the participants. Blood was drawn for calcium, phosphorus and vitamin D estimation. We measured serum 25 hydroxy vitamin D (25(OH)D) using the electrochemiluminescence method. Vitamin D deficiency and insufficiency were defined as (25(OH)D) < 20ng/ml and from 20ng/ml to <30 ng/ml respectively. To determine factors associated with vitamin D deficiency, we fit multivariable logistic regression models with exposure factors determined a priori. Data were analysed using Stata version 14.

Results

We enrolled 297 participants, 49.2% (167/297) of whom were males. The median infant age was nine weeks (interquartile range 7–13). All infants had less than one hour of sunlight exposure and over 90.6% (269/297) had received multivitamin supplements containing vitamin D. The prevalence of vitamin D deficiency was 12.1% (36/297): 95% CI (8.9%-16.4%). The prevalence of vitamin D insufficiency was 19.9% (59/297): 95% CI (15.7%-24.8%). Boys had higher odds of vitamin D deficiency compared to girls [adjusted odds ratio 2.8: 95% CI 1.3–6.1].

Conclusion

Vitamin D deficiency was 12.1% among low-birth-weight infants in Uganda although almost all of them had received multivitamin supplements containing vitamin D. We recommend that more studies are done in low-birth-weight infants to assess the risk factors for vitamin D in these population in Uganda.

Vitamin D Status and Potential Therapeutic Options in Critically Ill Patients: A Narrative Review of the Clinical Evidence

Vitamin D covers roles of paramount importance in the regulation of multiple physiological pathways of the organism. The metabolism of vitamin D involves kidney-liver crosstalk and requires an adequate function of these organs, where vitamin D is progressively turned into active forms. Vitamin D deficiency has been widely reported in patients living in the community, being prevalent among the most vulnerable subjects. It has been also documented in many critically ill patients upon admission to the intensive care unit. In this context, vitamin D deficiency may represent a risk factor for the development of life-threatening clinical conditions (e.g., infection and sepsis) and worse clinical outcomes. Several researchers have investigated the impact of vitamin D supplementation showing its feasibility, safety, and effectiveness, although conflicting results have put into question its real benefit in critically ill patients. The existing studies included heterogeneous critically ill populations and used slightly different protocols of vitamin D supplementation. For these reasons, pooling up the results is difficult and not conclusive. In this narrative review, we described vitamin D physiology and the pathophysiology of vitamin D depletion with a specific focus on critically ill patients with liver dysfunction, acute kidney injury, acute respiratory failure, and sepsis.

Evaluation of Functional and Symptomatic Outcomes After Vitamin D3 Administration in Carpal Tunnel Syndrome With Hypovitaminosis D

BACKGROUND

Vitamin D deficiency is now recognized as an independent risk factor and is involved in the pathogenesis of carpal tunnel syndrome (CTS). The purpose of this study was to evaluate the effects of vitamin D3 supplementation on functional and symptomatic outcomes in CTS patients with vitamin D deficiency.

METHODS

This was a prospective, single-arm study with a pretreatment or posttreatment quasi-experimental design. Carpal tunnel syndrome patients with vitamin D deficiency were treated with vitamin D3 (60 000 IU/week) plus standard treatment for a period of 3 months. Carpal tunnel syndrome-related pain and functional and symptomatic outcomes were assessed at baseline and at 3 months posttreatment using the Visual Analogue Scale (VAS) and the Boston Carpal Tunnel Questionnaire, respectively, along with serum vitamin D.

RESULTS

A total of 42 patients were analyzed. At 3 months posttreatment, there was a significant reduction in the severity of pain (VAS score) from baseline (Z = -5.71, P < .001). Similarly, the functional and symptomatic outcomes (Boston symptoms severity scale [SSS] and Boston functional status scale [FSS] score) at 3 months posttreatment significantly improved in comparison with baseline (Boston SSS: Z = -5.66, P < .001; Boston FSS: Z = -5.68, P < .001).

CONCLUSIONS

Vitamin D3 supplementation was associated with improvement in functional and symptomatic outcomes and CTS-related pain in CTS with vitamin deficiency. However, further robust randomized controlled trials are warranted to validate the results.

Vitamin D Levels in Patients with Overlap Syndrome, Is It Associated with Disease Severity?

Background: The coexistence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA) has been defined as overlap syndrome (OVS). Recently, a link between OSA, COPD and Vitamin D (Vit D) serum concentration was reported, however, evidence regarding Vit D status in patients with OVS is scarce. The aim of the present study was to evaluate Vit D serum levels and to explore the association of those levels with anthropometric, pulmonary function and sleep parameters in patients with OVS. Methods: Vit D serum levels were measured in patients diagnosed with OVS, as confirmed by overnight polysomnography and pulmonary function testing. Results: A total of 90 patients (79 males and 11 females) were included in the analysis. The patients were divided into three groups matched for age, gender, and BMI: the control group that included 30 patients (27 males and 3 females), the OSA group that included 30 patients (26 males and 4 females), and the OVS group that included 30 patients (26 males and 4 females). Patients with OVS exhibited decreased serum 25(OH)D levels compared with OSA patients and controls (14.5 vs. 18.6 vs. 21.6 ng/mL, p < 0.001). In the OVS group, multiple linear regression analysis identified AHI and FEV1, as predictors of serum 25(OH)D levels (p = 0.041 and p = 0.038, respectively). Conclusions: Lower Vit D levels have been observed in patients with OVS compared with OSA patients and non-apneic controls, indicating an increased risk of hypovitaminosis D in this population which might be associated with disease severity.

Stunting as a Risk Factor for Asthma: The Role of Vitamin D, Leptin, IL-4, and CD23+

Stunting, which results from chronic malnutrition, is common in children from low- and middle-income countries. Several studies have reported an association between obesity and asthma. However, only a handful of studies have identified stunting as a significant risk factor for wheezing, a symptom of asthma, although the underlying mechanism remains unclear. This article aimed to review possible mechanisms underlying asthma in stunted children. Overall, changes in diet or nutritional status and deficiencies in certain nutrients, such as vitamin D, can increase the risk of developing asthma. Vitamin D deficiency can cause linear growth disorders such as stunting in children, with lower levels of 25(OH)D found in underweight and stunted children. Stunted children show a decreased lean body mass, which affects lung growth and function. Low leptin levels during undernutrition cause a Th1–Th2 imbalance toward Th2, resulting in increased interleukin (IL)-4 cytokine production and total immunoglobulin E (IgE). Studies in stunted underweight children have also found an increase in the proportion of the total number of B cells with low-affinity IgE receptors (CD23+). CD23+ plays an important role in allergen presentation that is facilitated by IgE to T cells and strongly activates allergen-specific T cells and the secretion of Th2-driving cytokines. Stunted children present with low vitamin D and leptin levels, impaired lung growth, decreased lung function, and increased IL-4 and CD23+ levels. All of these factors may be considered consequential in asthma in stunted children.

Nonlinear Association between Serum 25-Hydroxyvitamin D and All-Cause Mortality in Adults with Inflammatory Bowel Disease in a Prospective Cohort Study

BACKGROUND

Nonlinear association between serum 25-hydroxyvitamin D [25(OH)D] concentration and all-cause mortality has been widely reported for the general population, but this association has not been quantified for individuals with inflammatory bowel disease (IBD).

OBJECTIVES

The aim was to explore the association between serum 25(OH)D and all-cause mortality in individuals with IBD.

METHODS

We identified 2690 females and 2532 males aged 40-69 y with diagnosed IBD at baseline in the UK Biobank. Serum 25(OH)D concentration was measured by direct competitive chemiluminescent immunoassay. The outcome was all-cause mortality, ascertained via the death registry. Cox proportional hazard regression was used to evaluate associations between serum 25(OH)D in quintiles and all-cause mortality among individuals with IBD [Crohn disease (CD; n = 1760) and ulcerative colitis (UC; n = 3462)]. Restricted cubic splines were used to investigate potential nonlinearity.

RESULTS

During the mean follow-up period of 11.9 y, 529 deaths (198 in CD and 331 in UC) were documented among 5222 individuals with IBD. Compared with the lowest quintile of serum 25(OH)D, HRs for the second to the highest quintiles were 0.82 (95% CI: 0.63, 1.06), 0.63 (95% CI: 0.47, 0.83), 0.64 (95% CI: 0.48, 0.85), and 0.74 (95% CI: 0.55, 0.99), respectively. Nonlinearity was detected in the dose-response association between serum 25(OH)D concentration and all-cause mortality (P-nonlinearity < 0.001), and 25(OH)D concentrations of 44-78 nmol/L were associated with a 50% lower risk of all-cause mortality (than 10 nmol/L). Subgroup analyses showed that the nonlinear association mostly applied to females (P-nonlinearity < 0.001 compared with 0.080 in males).

CONCLUSIONS

We observed a nonlinear association, mostly applicable to females, between serum 25(OH)D concentrations and all-cause mortality among individuals with IBD. A 25(OH)D concentration range of 44-78 nmol/L can serve as a starting point for future research to confirm recommended 25(OH)D concentrations for individuals with IBD.

The Relationships Between 25-Hydroxyvitamin D and Echocardiographic Parameters in Female Basketball Players

OBJECTIVE

This study was undertaken to (1) describe the cardiac structure and function and (2) to quantify the relationships between 25-hydroxyvitamin D [25(OH)D] and echocardiographic parameters in female basketball players.

DESIGN

A cross-sectional experimental design.

SETTING

Controlled laboratory setting.

PARTICIPANTS

Professional, female basketball players (n = 18).

INTERVENTION

25(OH)D and echocardiographic screening at the midpoint of the in-season phase, over a 2-week period in late Fall.

MAIN OUTCOME MEASURES

25(OH)D and echocardiographic parameters.

RESULTS

A high prevalence of vitamin D insufficiency was observed in the female players examined (77.8%), with most also displaying eccentric cardiac hypertrophy (77.8%). Nonsignificant, moderate correlations were found between 25(OH)D and structural echocardiographic parameters, including left atrium diameter (r = 0.34, P = 0.16), left ventricular (LV) end-systolic diameter (r = -0.46, P = 0.06), posterior wall thickness (r = 0.36, P = 0.14), LV mass (r = 0.30, P = 0.23), and LV index (r = 0.33, P = 0.18). Significant, large correlations were found between 25(OH)D and echocardiographic parameters indicative of systolic function, including LV ejection fraction (r = 0.59, P = 0.01), fractional shortening (r = 0.59, P = 0.01), and peak systolic mitral tissue velocity (r = 0.51, P = 0.003). Similarly, a significant, large correlation was found between 25(OH)D and diastolic function as indicated by mitral valve inflow deceleration time (r = 0.51, P = 0.03).

CONCLUSIONS

Our findings suggest the importance of female basketball players maintaining 25(OH)D concentration, given its possible physiological benefits on cardiac structure and function.

Lower vitamin D levels and VDR variants are risk factors for breast cancer: an updated meta-analysis

Inadequate vitamin D levels and vitamin D variants have been shown to be associated with breast cancer (BC), however the results are inconsistent. To reach a definitive conclusion the present meta-analysis was conducted. When compared to healthy controls, BC patients had reduced vitamin D levels (standard difference in means = -0.564, p = 0.003). The meta-analysis revealed that the FokI mutation was linked with an increased BC susceptibility (CC vs. TT: OR = 1.107, p = 0.001, CC vs. TC + TT: OR = 1.114, p = 0.020). There was no role of other VDR variants (BsmI, TaqI, and ApaI). FokI mutation and diminished vitamin D increase the likelihood of developing BC.

Vitamin D and Its Receptor from a Structural Perspective

The activities of 1α,25-dihydroxyvitamin D3, 1,25D₃, are mediated via its binding to the vitamin D receptor (VDR), a ligand-dependent transcription factor that belongs to the nuclear receptor superfamily. Numerous studies have demonstrated the important role of 1,25D₃ and VDR signaling in various biological processes and associated pathologies. A wealth of information about ligand recognition and mechanism of action by structural analysis of the VDR complexes is also available. The methods used in these structural studies were mainly X-ray crystallography complemented by NMR, cryo-electron microscopy and structural mass spectrometry. This review aims to provide an overview of the current knowledge of VDR structures and also to explore the recent progress in understanding the complex mechanism of action of 1,25D₃ from a structural perspective.

The effect of vitamin D supplementation on tobacco-related disorders in individuals with a tobacco use disorder: a randomized clinical trial

Vitamin D deficiency in cigarette smokers (CS) might associate with several complications, including metabolic deficits, depression and anxiety. This study evaluated the effects of vitamin D on mental health symptoms, nicotine misuse, and biomarkers of metabolic diseases in individuals with a tobacco use disorder. A randomized, double-blind, placebo-controlled trial was conducted with 60 CS subjects receiving either 50,000 IU vitamin D supplements (n = 30) or placebo (n = 30) every 2 weeks for 24-weeks. Nicotine misuse, mental health scale, and metabolic parameters were measured before and after the intervention in the CS subjects. Compared with the placebo-group, after the 24-weeks intervention, serum 25 (OH) vitamin D levels increased in the intervention group (β 2.96; 95% CI, 0.91, 5.01; P = 0.006). In addition, vitamin D supplementation significantly improved Beck Depression Inventory (BDI) (β -2.06; 95% CI, -3.84, -0.28; P = 0.02). In addition, vitamin D administration significantly decreased fasting plasma glucose (FPG) (β -4.56; 95% CI, -8.94, -0.19; P = 0.04), insulin (β -0.50; 95% CI, -0.88, -0.13; P = 0.009), and homeostasis model of assessment-estimated insulin resistance (HOMA-IR) levels (β -0.21; 95% CI, -0.33, -0.08; P = 0.001). Furthermore, vitamin D resulted in a significant elevation in total antioxidant capacity (TAC) (β 81.20; 95% CI, 18.30, 144.11; P = 0.01), and plasma glutathione (GSH) levels (β 73.05; 95% CI, 18.56, 127.54; P = 0.01), compared with the placebo-group. Administration of vitamin D for 24-weeks to CS subjects had beneficial effects on symptoms of depression and several metabolic biomarkers. While this preliminary study suggests that vitamin D might have beneficial effects, its clinical efficacy in individuals with a tobacco use disorder should be further validated in future clinical trials.

Oxidative-Stress-Sensitive microRNAs in UV-Promoted Development of Melanoma

Simple Summary

Exposure to ultraviolet (UV) rays from the sun is one of the most important modifiable risk factors for skin cancer. Melanoma is the most life-threatening type of skin cancer. UV-induced DNA damage and oxidative stress represent two main mechanisms that, directly and indirectly, contribute to melanomagenesis. In addition, an interplay of abnormally expressed microRNAs (miRNAs) and redox imbalance is a hallmark in several cancers, including melanoma. UV radiation can be the central hub between these two cellular aberrations, as it is able to stimulate both. Here, to gain new mechanistic insights into melanomagenesis and identify new therapeutic targets for the prevention and treatment of melanoma, we report current evidence suggesting a complex interaction between UV-promoted deregulation of redox-sensitive miRNAs and known signal-transduction pathways underlying malignant transformation of melanocytes to melanoma.

Abstract

Melanoma is the most aggressive and life-threatening form of skin cancer. Key molecular events underlying the melanocytic transformation into malignant melanoma mainly involve gene mutations in which exposure to ultraviolet (UV) radiation plays a prominent role. However, several aspects of UV-induced melanomagenesis remain to be explored. Interestingly, redox-mediated signaling and perturbed microRNA (miRNA) profiles appear to be interconnected contributing factors able to act synergistically in melanoma initiation and progression. Since UV radiation can promote both redox imbalance and miRNA dysregulation, a harmful crosstalk between these two key cellular networks, with UV as central hub among them, is likely to occur in skin tissue. Therefore, decoding the complex circuits that orchestrate the interaction of UV exposure, oxidative stress, and dysregulated miRNA profiling can provide a deep understanding of the molecular basis of the melanomagenesis process. Furthermore, these mechanistic insights into the reciprocal regulation between these systems could have relevant implications for future therapeutic approaches aimed at counteracting UV-induced redox and miRNome imbalances for the prevention and treatment of malignant melanoma. In this review, we illustrate current information on the intricate connection between UV-induced dysregulation of redox-sensitive miRNAs and well-known signaling pathways involved in the malignant transformation of normal melanocytes to malignant melanoma.

Features of the content of matrix metalloproteinases ММР-9 and ММР-2 in mixed saliva of young individuals with dental caries against the background of different level of 25(OH) vitamin D in the body

The content ofММР-9 and ММР-2 in oral fluid of 105 individuals between the ages of 19 and 23 has been researched.Of these, 42 people are individuals with dental caries and normal level of the active form of vitamin Din serum (25(OH)D >30ng/mL) and 42 people - with 25(OH)D <30 ng/mL level.The control group was composed of 21 individuals with low DMFt index (1,5) and a normal level of 25(OH)D in blood. It has been established that the level of ММР-9 in mixed salivaincreases against the background of dental caries,while the content of ММР-9 and ММР-2 increasessignificantlyamidthe lack and deficiency of25(OH)Din the body. Inverse correlations between the 25(OH)D level in serum and the value ofmatrix metalloproteinasesin saliva have been revealed: noticeable - with the amount of MMP-9 and moderate- with the concentration of MMP-2.

A comprehensive look into the association of vitamin D levels and vitamin D receptor gene polymorphism with obesity in children

Childhood obesity accounts for several psychosocial and clinical consequences. Psychosocial consequences include lower self-esteem, social isolation, poor academic achievement, peer problems, and depression, whereas clinical consequences are cardiovascular diseases, type 2 diabetes, dyslipidemia, cancer, autoimmune diseases, girls early polycystic ovarian syndrome (PCOS), asthma, bone deformities, etc. A growing number of studies have uncovered the association of childhood obesity and its consequences with vitamin-D (vit-D) deficiency and vitamin-D receptor (VDR) gene polymorphisms such as single nucleotide polymorphisms (SNPs), e.g., TaqI, BsmI, ApaI, FokI, and Cdx2. Considering the impact of vit-D deficiency and VDR gene polymorphisms, identifying associated factors and risk groups linked to lower serum vit-D levels and prevention of obesity-related syndromes in children is of utmost importance. Previously published review articles mainly focused on the association of vit-D deficiency with obesity or other non-communicable diseases in children. The nature of the correlation between vit-D deficiency and VDR gene polymorphisms with obesity in children is yet to be clarified. Therefore, this review attempts to delineate the association of obesity with these two factors by identifying the molecular mechanism of the relationship.

Vitamin D Status and Parkinson's Disease

Parkinson’s disease (PD) is a complex and progressive neurodegenerative disease, characterized by resting tremor, rigidity, slowness of movement, and postural instability. Furthermore, PD is associated with a wide spectrum of non-motor symptoms that add to overall disability. In recent years, some investigations, from basic science to clinical applications, have focused on the role of vitamin D in PD, often with controversial findings. Vitamin D has widespread effects on several biological processes in the central nervous system, including neurotransmission in dopaminergic neural circuits. Various studies have recorded lower levels of vitamin D in PD patients than in healthy controls. Low vitamin D status has also been correlated with the risk for PD and motor severity, whereas less is known about the effects vitamin D has on cognitive function and other non-motor symptoms. This review aims to better characterize the correlation between vitamin D and PD, clarify the role of vitamin D in PD prevention and treatment, and discuss avenues for future research in this field.