Vitamin D in health and disease: current perspectives

Relationship between thyroid-stimulating hormone levels and the severity of vitamin D deficiency by age group

OBJECTIVE

Researchers have long been captivated by the complex molecular interactions between vitamin D and the thyroid gland. Hypothyroidism affects 2% to 4% of women of reproductive age and can impact fertility through anovulatory cycles, luteal phase defects, hyperprolactinemia, and sex hormone imbalances. This study investigated the relationship between thyroid disease and the severity of vitamin D deficiency across different age groups.

METHODS

A retrospective study was conducted of 286 patient samples from individuals aged 18 to 60 years who were processed in the clinical biochemistry laboratory of our hospital. Samples were tested for thyroid-stimulating hormone (TSH) and vitamin D (specifically, vitamin D3) levels. The study samples were categorized into four clinically relevant groups based on TSH levels and into three groups based on serum 25-hydroxyvitamin D (25(OH)D) levels.

RESULTS

Most of the samples were from female patients (n=269), and the most common age group was 18 to 35 years (n=191, 66.78%). Subclinical hypothyroidism was identified in 120 patients, while vitamin D deficiency was present in 237 (82.87%) participants. A significant association was observed between vitamin D deficiency and the presence of thyroid disorders. Additionally, a significant negative correlation was found between TSH and vitamin D levels. Polycystic ovary syndrome was noted in 103 female patients (36.01%).

CONCLUSION

TSH and 25(OH)D levels should be screened in all women of reproductive age, not just those in high-risk groups, as subclinical and occult hypothyroidism may otherwise go undiagnosed. Furthermore, TSH should be considered the primary screening test.

Unveiling Racial Disparities in Localized Prostate Cancer: A Systems-Level Exploration of the lncRNA Landscape

BACKGROUND/OBJECTIVES

Prostate cancer (PC) is the most common non-cutaneous cancer in men globally, and one which displays significant racial disparities. Men of African descent (AF) are more likely to develop PC and face higher mortality compared to men of European descent (EU). The biological mechanisms underlying these differences remain unclear. Long non-coding RNAs (lncRNAs), recognized as key regulators of gene expression and immune processes, have emerged as potential contributors to these disparities. This study aimed to investigate the regulatory role of lncRNAs in localized PC in AF men relative to those of EU and assess their involvement in immune response and inflammation.

METHODS

A systems biology approach was employed to analyze differentially expressed (DE) lncRNAs and their roles in prostate cancer (PC). Immune-related pathways were investigated through over-representation analysis of lncRNA-mRNA networks. The study also examined the effects of vitamin D supplementation on lncRNA expression in African descent (AF) PC patients, highlighting their potential regulatory roles in immune response and inflammation.

RESULTS

Key lncRNAs specific to AF men were identified, with several being implicated for immune response and inflammatory processes. Notably, 10 out of the top 11 ranked lncRNAs demonstrated strong interactions with immune-related genes. Pathway analysis revealed their regulatory influence on antigen processing and presentation, chemokine signaling, and ribosome pathways, suggesting their critical roles in immune regulation.

CONCLUSIONS

These findings highlight the pivotal role of lncRNAs in PC racial disparities, particularly through immune modulation. The identified lncRNAs may serve as potential biomarkers or therapeutic targets to address racial disparities in PC outcomes.

Comparative Analyses of the Safety Profiles of Vitamin D Receptor Agonists: A Pharmacovigilance Study Based on the EudraVigilance Database

Background/Objectives: Vitamin D receptor (VDR) agonists are commonly used in clinical practice for their roles in calcium regulation and potential benefits in various diseases. However, their safety profiles, particularly for compounds available as food supplements, remain underexplored in real-world settings. This study aimed to analyze the safety profiles of VDR agonists using the EudraVigilance database, focusing on adverse drug reactions (ADRs) reported between 1 January 2004 and 23 June 2024. Methods: Data for ten VDR agonists were collected, de-duplicated, and analyzed to identify specific safety signals. Risk factors for specific ADRs were assessed using multiple logistic regression. Results: This study analyzed 5,369,581 reports in the EudraVigilance system, from which 17,947 reports (0.33%) involving 80,050 ADRs were linked to VDR agonists. The most-reported drugs were cholecalciferol (12,944 cases) and calcitriol (1355 cases). Serious ADRs were more prevalent with paricalcitol, alfacalcidol, and calcitriol than with cholecalciferol (p < 0.05). Hypercalcemia was a hallmark ADR for all VDR agonists, with the highest risk linked to dihydrotachysterol (ROR = 5668; 95%CI = 3332 to 9641; p < 0.0001), alfacalcidol (ROR = 965.7; 95%CI = 843.6 to 1106; p < 0.0001), and calcitriol (ROR = 726.0; 95%CI = 634.6 to 830.5; p < 0.0001). Logistic regression highlighted dehydration, overdose, and concomitant administration of calcium salts as major predictors of hypercalcemia. The co-administration of multiple VDR agonists was also found to increase hypercalcemia risk. However, the disproportionality analysis showed that only active VDR agonists (e.g., calcitriol, alfacalcidol) were associated with severe complications like renal and urinary disorders and cardiac issues due to hypercalcemia. Natural precursors (cholecalciferol, ergocalciferol) were more often linked to non-calcemic ADRs such as gastrointestinal symptoms, which were more prevalent in infants and children compared to adults. Conclusions: The safety profiles of VDR agonists differ significantly between compounds. Active derivatives require close monitoring for serious calcemia-related complications, whereas cholecalciferol is associated with less severe ADRs, primarily in at-risk populations. These findings highlight the need for targeted safety monitoring and further research into the real-world uses of VDR agonists.

Analysis of Usual Consumption of Vitamin D Among Adult Individuals in Italy

Background: The condition of vitamin D (25OHD) deficiency represents an important public health problem. In Europe, hypovitaminosis is common not only in the elderly population but also between 50 and 70 years, both in males and females. Data regarding vitamin D intake in the Italian population are very limited. In a recent paper, reporting data collected by a specific Frequency Food Questionnaire (FFQ), we observed in a small group of healthy subjects that the dietary consumption of vitamin D, both in females and males, was far below the average. Methods: With the aim of expanding our preliminary data, we conducted a survey on a large cohort of subjects from different areas of Northern, Central, and Southern Italy. The FFQ contained 11 different questions regarding the amount and type of intake of foods containing ergocalciferol and cholecalciferol. It was submitted to 870 subjects, 627 females and 243 males, with an age range from 40 to 80 years; 31.6% of the studied population was apparently in good health, while 68.4% were affected by different pathologies. Results: The present data confirm previous observations: the global quantity of vitamin D intake in 14 days was 70.8 μg (±1.8 SE, ±54.4 SD) in females and 87.5 μg (±1.9 SE, ±57.1 SD) in males; the mean daily intake of vitamin D in females and males was 5.05 μg (±0.5 SE, ±3.8 SD) and 6.25 μg (±0.21 SE, ±4.1 SD), respectively. In healthy subjects, a gradual decrease was observed in the overall intake of vitamin D in both females and males according to an increase in age bracket, ranging from 74.5 μg and 103.8 μg in the 40-50 age group to 54.5 μg and 87.8 μg in the 71-80 age group, respectively. Conclusions: In conclusion, the present data, collected in a large Italian cohort, underscore that the daily intake of vitamin D is far below the recommended daily average, thereby contributing to the development of potential hypovitaminosis.

Response to treatment and low serum vitamin D levels in North Indian patients with treatment-naive category I and multi-drug resistant pulmonary tuberculosis

BACKGROUND

Tuberculosis (TB) is a bacterial infection that usually affects the lungs, although it can also affect other parts of the body. Vitamin D deficiency and response to treatment have been demonstrated in patients with active TB in several studies, but not in MDR-TB patients, which is a new observation in the present study.

OBJECTIVE

To study the time to initial sputum culture conversion and to associate baseline vitamin D levels and response to treatment in patients with PTB Cat I and MDR-TB.

METHODS

A total of 897 North Indian participants were recruited and divided into three groups: treatment-naïve PTB Cat I, MDR-TB, and healthy controls. Serum biochemistry, including 25-hydroxyvitamin D and calcium, was measured in all participants with PTB, Cat I, and MDR-TB.

RESULTS

PTB Cat I patients had high bacillary load grading at baseline compared to 2nd month followed by 6th month of treatment. More severe chest radiographic features, such as cavitation and the presence of bilateral disease at baseline. Mean sputum smear conversion times were 0.95 ± 0.7 months and culture conversion to negative occurred at a mean time of 0.8 ± 0.7 in PTB Cat I patients compared to MDR-TB patients on average sputum smear and time of 2.4 ± 3 months. Significantly lower mean serum 25-hyroxyvitamin D concentration was found in the 6th month than in the 2nd month and baseline in PTB Cat I.

CONCLUSION

Low serum vitamin D deficiency was observed in both groups during treatment and is one of the important factors responsible for susceptibility to TB in both groups; however, its significance is uncertain. Patients with continuous positive sputum for multidrug-resistant tuberculosis (MDR-TB) had a worse prognosis than those with sputum bacteriology conversion. Two months into a treatment regimen, sputum smear conversions may be a useful indicator of an MDR-TB patient's prognosis.

Nutrition, hydration and supplementation considerations for mountaineers in high-altitude conditions: a narrative review

Staying and climbing in high mountains (>2,500 m) involves changes in diet due to poor access to fresh food, lack of appetite, food poisoning, environmental conditions and physiological changes. The purpose of this review is to summarize the current knowledge on the principles of nutrition, hydration and supplementation in high-altitude conditions and to propose practical recommendations/solutions based on scientific literature data. Databases such as Pubmed, Scopus, ScienceDirect and Google Scholar were searched to find studies published from 2000 to 2023 considering articles that were randomized, double-blind, placebo-controlled trials, narrative review articles, systematic reviews and meta-analyses. The manuscript provides recommendations for energy supply, dietary macronutrients and micronutrients, hydration, as well as supplementation recommendations and practical tips for mountaineers. In view of the difficulties of being in high mountains and practicing alpine climbing, as described in the review, it is important to increase athletes' awareness of nutrition and supplementation in order to improve well-being, physical performance and increase the chance of achieving a mountain goal, and to provide the appropriate dietary care necessary to educate mountaineers and personalize recommendations to the needs of the individual.

Association between vitamin D and cardiovascular health in Chinese children and adolescents: Basing on Life's Essential 8

BACKGROUND AND AIMS

The relationship between vitamin D and cardiovascular health (CVH) in children remains unclear. We aimed to explore the association between vitamin D and CVH metrics using the latest Life's Essential 8 (LE8) among Chinese children and adolescents.

METHODS AND RESULTS

A cross-sectional study containing 2680 participants aged 7-18 years (1340 boys and 1340 girls) was performed in South China in 2013. Vitamin D levels were categorized as follows: ≥20 ng/mL (sufficiency), 12 - < 20 ng/mL (inadequacy), and <12 ng/mL (deficiency). The CVH metrics of LE8 was assessed by overall CVH score, health behavior score, health factor score and high CVH, among which the health behaviors included diet, physical activity, nicotine exposure, and sleep health, as well as the health factors contained body mass index, blood lipids, blood glucose, and blood pressure. Different regression models were used to assess the associations between vitamin D levels and CVH metrics of LE8. Results showed that the prevalence of vitamin D deficiency and inadequacy was 7.5% and 44.4%, respectively. Boys had lower levels in overall CVH score, health behavior score, and health factor score than girls. After adjusting for potential confounds, upward trends in diet score, health behavior score, and high CVH were observed with increasing vitamin D levels.

CONCLUSION

Vitamin D levels were positively associated with high CVH based on LE8, and more attention should be paid on boys due to whose lower levels in CVH metrics.

Vitamin D in Cancer Prevention and Treatment: A Review of Epidemiological, Preclinical, and Cellular Studies

Inhibition of human carcinomas has previously been linked to vitamin D due to its effects on cancer cell proliferation, migration, angiogenesis, and apoptosis induction. The anticancer activity of vitamin D has been confirmed by several studies, which have shown that increased cancer incidence is associated with decreased vitamin D and that dietary supplementation of vitamin D slows down the growth of xenografted tumors in mice. Vitamin D inhibits the growth of cancer cells by the induction of apoptosis as well as by arresting the cells at the G0/G1 (or) G2/M phase of the cell cycle. Aim and Key Scientific Concepts of the Review: The purpose of this article is to thoroughly review the existing information and discuss and debate to conclude whether vitamin D could be used as an agent to prevent/treat cancers. The existing empirical data have demonstrated that vitamin D can also work in the absence of vitamin D receptors (VDRs), indicating the presence of multiple mechanisms of action for this sunshine vitamin. Polymorphism in the VDR is known to play a key role in tumor cell metastasis and drug resistance. Although there is evidence that vitamin D has both therapeutic and cancer-preventive properties, numerous uncertainties and concerns regarding its use in cancer treatment still exist. These include (a) increased calcium levels in individuals receiving therapeutic doses of vitamin D to suppress the growth of cancer cells; (b) hyperglycemia induction in certain vitamin D-treated study participants; (c) a dearth of evidence showing preventive or therapeutic benefits of cancer in clinical trials; (d) very weak support from proof-of-principle studies; and (e) the inability of vitamin D alone to treat advanced cancers. Addressing these concerns, more potent and less toxic vitamin D analogs have been created, and these are presently undergoing clinical trial evaluation. To provide key information regarding the functions of vitamin D and VDRs, this review provided details of significant advancements in the functional analysis of vitamin D and its analogs and VDR polymorphisms associated with cancers.

Advances in biomedical applications of vitamin D for VDR targeted management of obesity and cancer

BACKGROUND

1,25(OH)2D3 is a fat-soluble vitamin, involved in regulating Ca2+ homeostasis in the body. Its storage in adipose tissue depends on the fat content of the body. Obesity is the result of abnormal lipid deposition due to the prolonged positive energy balance and increases the risk of several cancer types. Furthermore, it has been associated with vitamin D deficiency and defined as a low 25(OH)2D3 blood level. In addition, 1,25(OH)2D3 plays vital roles in Ca2+-Pi and glucose metabolism in the adipocytes of obese individuals and regulates the expressions of adipogenesis-associated genes in mature adipocytes.

SCOPE AND APPROACH

The present contribution focused on the VDR mediated mechanisms interconnecting the obese condition and cancer proliferation due to 1,25(OH)2D3-deficiency in humans. This contribution also summarizes the identification and development of molecular targets for VDR-targeted drug discovery.

KEY FINDINGS AND CONCLUSIONS

Several studies have revealed that cancer development in a background of 1,25(OH)2D3 deficient obesity involves the VDR gene. Moreover, 1,25(OH)2D3 is also known to influence several cellular processes, including differentiation, proliferation, and adhesion. The multifaceted physiology of obesity has improved our understanding of the cancer therapeutic targets. However, currently available anti-cancer drugs are notorious for their side effects, which have raised safety issues. Thus, there is interest in developing 1,25(OH)2D3-based therapies without any side effects.

Vitamin D receptor gene polymorphisms and multiple myeloma: a meta-analysis

Vitamin D acts through the vitamin D receptor (VDR), and vitamin D level decreases in multiple myeloma (MM) patients. Single nucleotide polymorphisms in VDR alter its functions to affect the vitamin D status. This raises the question of whether VDR gene polymorphisms are associated with MM risk, which has been investigated in case‒control studies, but the results have been inconsistent. This meta-analysis aimed to investigate the relationship between VDR gene polymorphisms and MM risk. The PubMed, Web of Science, Medline, Embase, Chinese National Knowledge Infrastructure (CNKI), Chinese Scientific Journal (VIP), Wanfang Databases (WANFANG) were searched from inception to June 1, 2023, without language restriction or publication preference. Pooled odds ratio (OR) and 95% confidence interval (CI) for each variable were calculated. Leave-one-out sensitivity analysis was performed to determine the source of heterogeneity. Publication bias was assessed using Begg' and Egger's tests, and the trim-and-fill method was used to compensate for publication bias. The correlation meta-analysis was conducted using Comprehensive Meta-Analysis 3.0 and STATA 12.0 software. All the included studies were based on Asian populations and involved four VDR gene polymorphisms, TaqI (rs731236), ApaI (rs7975232), BsmI (rs1544410) and FokI (rs2228570). The results showed that TaqI (C vs. T: OR = 1.487, 95% CI 1.052, 2.104, P = 0.025; CC + CT vs. TT: OR = 1.830, 95% CI 1.138, 2.944, P = 0.013), ApaI (T vs. G: OR = 1.292, 95% CI 1.101, 1.517, P = 0.002; TT vs. GG: OR = 1.600, 95% CI 1.106, 2.314, P = 0.013; TG vs. GG: OR 1.305, 95% CI 1.050, 1.622; P = 0.016; TT + TG vs. GG: OR = 1.353, 95% CI 1.103, 1.662, P = 0.004), BsmI (GG vs. AA: OR = 1.918, 95% CI 1.293, 2.844, P = 0.001; GA vs. AA: OR = 1.333, 95% CI 1.058, 1.679, P = 0.015; G vs. A: OR = 1.398, 95% CI 1.180, 1.657, P = 0.000; GG vs. AA + GA: OR = 1.686, 95% CI 1.174, 2.423, P = 0.005), and FokI (T vs. C: OR = 1.687, 95% CI 1.474, 1.931, P = 0.000; TT vs. CC: OR = 2.829, 95% CI 2.066, 3.872, P = 0.000; TC vs. CC: OR = 1.579, 95% CI 1.304, 1.913, P = 0.000, TT + TC vs. CC: OR = 1.771, 95% CI 1.477, 2.125, P = 0.000; TT vs. CC + TC: OR = 2.409, 95% CI 1.814, 3.200, P = 0.000) are associated with MM risk. VDR gene polymorphisms including ApaI, BsmI, TaqI, and FokI are associated with MM risk in Asian populations. Additional studies with large sample sizes and different ethnicities are needed.

Ablation of Vitamin D Signaling in Cardiomyocytes Leads to Functional Impairment and Stimulation of Pro-Inflammatory and Pro-Fibrotic Gene Regulatory Networks in a Left Ventricular Hypertrophy Model in Mice

The association between vitamin D deficiency and cardiovascular disease remains a controversial issue. This study aimed to further elucidate the role of vitamin D signaling in the development of left ventricular (LV) hypertrophy and dysfunction. To ablate the vitamin D receptor (VDR) specifically in cardiomyocytes, VDRfl/fl mice were crossed with Mlcv2-Cre mice. To induce LV hypertrophy experimentally by increasing cardiac afterload, transverse aortic constriction (TAC) was employed. Sham or TAC surgery was performed in 4-month-old, male, wild-type, VDRfl/fl, Mlcv2-Cre, and cardiomyocyte-specific VDR knockout (VDRCM-KO) mice. As expected, TAC induced profound LV hypertrophy and dysfunction, evidenced by echocardiography, aortic and cardiac catheterization, cardiac histology, and LV expression profiling 4 weeks post-surgery. Sham-operated mice showed no differences between genotypes. However, TAC VDRCM-KO mice, while having comparable cardiomyocyte size and LV fibrosis to TAC VDRfl/fl controls, exhibited reduced fractional shortening and ejection fraction as measured by echocardiography. Spatial transcriptomics of heart cryosections revealed more pronounced pro-inflammatory and pro-fibrotic gene regulatory networks in the stressed cardiac tissue niches of TAC VDRCM-KO compared to VDRfl/fl mice. Hence, our study supports the notion that vitamin D signaling in cardiomyocytes plays a protective role in the stressed heart.

The effect of vitamin D2 supplementation on vitamin D levels in humans: A time and dose-response meta-analysis of randomized controlled trials

BACKGROUND

Inconsistencies exist regarding the influence of vitamin D2 (ergocalciferol) supplementation on serum vitamin D levels. These inconsistencies could be attributed to numerous factors, such as dosage, baseline vitamin D levels, and duration of intervention. Hence, this dose-response meta-analysis of randomized controlled trials was conducted to assess the efficacy of vitamin D2 supplementation on vitamin D levels.

METHODS

Relevant studies were searched in PubMed/Medline, Web of Science, Embase, and Scopus, from their inception to 3 January 2023. Variable alterations were considered to calculate the pooled weighted mean difference (WMD) with 95% confidence interval (CI) using the random effects model.

RESULTS

Pooled results from 33 study arms demonstrated that Vitamin D2 treatment significantly increases total vitamin D concentrations (WMD: 11.47 ng/mL, 95 %CI: 9.29 to 13.64, p < 0.001), 25(OH)D2 concentrations (WMD: 11.40 ng/mL, 95 %CI: 4.72 to 18.09, p = 0.001), and 1,25(OH)D concentrations (WMD: 5.61 ng/mL, 95 %CI: 0.74 to 10.48, p = 0.024), but decreases 25(OH)D3 concentrations (WMD: -4.63 ng/mL, 95 %CI: -6.46 to -2.81, p < 0.001). In subgroup analyses, increase in total vitamin D concentrations was more significant in vitamin D2 doses >2000 IU/day (WMD: 13.82 ng/mL), studies with duration ≤12 weeks (WMD: 12.53 ng/mL), participants aged ≥60 years (WMD: 14.40 ng/mL), and trials with basal 25(OH)D concentrations <20 ng/mL (WMD: 11.47 ng/mL).

CONCLUSIONS

This meta-analysis indicates that the supplementation of vitamin D2 significantly increases the serum concentrations of total vitamin D, 25(OH)D2, and 1,25(OH)D, but decreases 25(OH)D3 concentrations. Careful consideration of patient characteristics, dosage, and treatment duration is recommended for vitamin D2 supplementation.

An Adapted Questionnaire Tailored for Assessing the Risk of Vitamin D Deficiency in Children That Is Proving Useful in Guiding Clinical Interventions

BACKGROUND

The identification of vitamin D (VitD) deficiency in pediatric populations is essential for preventive healthcare. We refined and tested the Evaluation of Deficiency Questionnaire (EVIDENCe-Q) for its utility in detecting VitD insufficiency among children.

PATIENTS AND METHODS

We enrolled 201 pediatric patients (aged between 3 and 18 years). Clinical evaluation and serum vitamin D levels were assessed in all subjects. The EVIDENCe-Q was updated to incorporate factors influencing VitD biosynthesis, intake, assimilation, and metabolism, with scores spanning from 0 (optimal) to 36 (poor).

RESULTS

We established scores for severe deficiency (<10 mg/dL) at 20, deficiency (<20 mg/dL) at 22, and insufficiency (<30 mg/dL) at 28. A score of 20 or greater was determined as the optimal cut-off for distinguishing VitD deficient from sufficient statuses, as evidenced by ROC curve analysis AUC = 0.7066; SE = 0.0841; sensitivity 100%, 95% CI 0.561-1. The most accurate alignment was seen with VitD insufficiency, defined as 25-OH-D3 < 20 ng/mL.

CONCLUSIONS

This study confirms that the EVIDENCe-Q is a valid instrument for assessing the risk of vitamin D deficiency and insufficiency in children. It offers a practical approach for determining the need for clinical intervention and dietary supplementation of VitD in the pediatric population.

Analysis of Health Ailments and Associated Risk Factors in Small-Scale Fisherfolk Community of Indian Sundarbans: A Cross-Sectional Study

Background

Small-scale fishers of Indian Sundarbans depend on open-water fisheries for their livelihoods. They often face health, occupational, and safety issues in their profession due to environmental, socio-economic, and policy changes. The morbidity pattern and related risk factors are important indicators of well-being for any community, hence applicable to small-scale fishers of Sundarbans. The present study was designed to assess patterns of morbidities, associated risk factors including occupational health hazards, and treatment-seeking behavior of small-scale fishers in the Indian Sundarbans.

Material and Methods

Household surveys, focused group discussions, and personal interviews were conducted through a predesigned pretested structured questionnaire. Associated risk factors and the nature of seeking treatment were considered during the data collection covering 650 individuals from 132 fishers' families.

Results

Morbidities were more frequent in males (39.33%) than in females (28.5%). The fever (31%) was the most dominant reason for morbidities followed by ocular ailments (23%), musculoskeletal disorder (20%), dermatological ailments (17%), and respiratory illness (9%). The highest morbidities (25%) were recorded in the age group of 21-30 years in males while that was 20% in the 11-20 years age group in the case of the females. Physical labor for fishing activities predisposes to health ailments of the studied population.

Conclusions

The prevalence of morbidity among the fishermen community was found to be 28.5%. The understanding of the morbidity profile of a population in general and specific age groups of both sexes in specific sheds light on the vulnerability of working groups that will help for effective healthcare planning and resource allocation.

The Global Prevalence of Vitamin D Deficiency in the Elderly: A Meta-analysis

Background

Vitamin D deficiency is widely prevalent among the elderly, posing significant health risks. This study aims to determine the global prevalence of vitamin D deficiency in the elderly.

Methods

A systematic review and meta-analysis was conducted, examining databases including Scientific Information Database (SID), Medline (PubMed), ScienceDirect, Scopus, Embase, and Google Scholar until January 2023. The publication bias of the studies was assessed using the I2 test of heterogeneity and the Egger test.

Results

The prevalence of vitamin D deficiency, defined as levels below 20 ng or 50 nmol was found to be 59.7% (95% CI 45.9-72.1). Furthermore, a review of six studies involving 6748 elderly individuals showed a prevalence of 27.5% (95% CI 21.8-34.1) for deficiency defined between 20 and 30 ng or 50-75 nmol. Additionally, a meta-analysis of seven studies with a sample size of 6918 elderly individuals reported a prevalence of 16% (95% CI 10.2-24.1) for deficiency defined above 30 nmol or 75 nmol.

Conclusion

The results of the present study reveal that the prevalence of vitamin D deficiency among the elderly is high and requires the attention of health policymakers at the World Health Organization to prioritize extensive information dissemination and screening to mitigate the adverse effects on their quality of life.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-023-01089-w.

Prevalence of vitamin D deficiency and its association with cardiometabolic risk factors among healthcare workers in the Eastern Cape province, South Africa; cross-sectional study

This study assesses the prevalence of Vitamin D deficiency and its potential association with cardiometabolic risk factors among South African adults residing in the Eastern Cape province. In this cross-sectional study, 1244 healthcare workers (HCWs) completed a self-administered questionnaire and venous blood samples were drawn at two academic hospitals in the Eastern Cape. History of hypertension and diabetes mellitus were self-reported. Participants were categorised as obese if their body mass index (BMI) ≥ 30 kg/m2. Participants were classified as having metabolic syndrome if they had hypertension, diabetes mellitus and obesity. Vitamin D [25(OH)D] deficiency was defined as venous blood concentrations < 50 nmol/L. Associations between vitamin D deficiency and participants' characteristics were assessed using multivariate logistic regression model analysis. The prevalence of vitamin D deficiency was 28.5% (n = 355), of whom 292 were female. Among the participants who were deficient in vitamin D, the prevalence of obesity, diabetes mellitus, hypertension, chronic kidney disease, and metabolic syndrome was 64.9% (n = 230), 9% (n = 32), 16.6% (n = 59), 2.3% (n = 8) and 18% (n = 64), respectively. In the adjusted multivariate logistic regression model, black Africans (AOR = 2.87; 95% CI 1.52-5.43) and individuals ≥ 42 years (AOR = 1.37; 95% CI 1.07-1.77) were more likely to exhibit vitamin D deficiency. However, there was no significant association by age, sex, and cardiometabolic markers. More than one in four healthcare workers was deficient in vitamin D among the study sample, especially the black Africans and older individuals. Further studies are needed at the population level to elucidate on the vitamin D status in the region.

Multiple electrolytes imbalances in a patient with inflammatory bowel disease associated with vitamin D deficiency: a case report

BACKGROUND

Inflammatory bowel disease involves chronic inflammation and ulceration, primarily Crohn's disease and ulcerative colitis. The prevalence of inflammatory bowel disease is rising in industrialized countries. We describe the case of a patient with inflammatory bowel disease and multiple electrolyte disturbances that emphasize the link between a vitamin D deficiency and electrolyte imbalances.

CASE

An 86-year-old Japanese man with severe hypocalcemia, hypophosphatemia, hypokalemia, and hypomagnesemia was referred to the gastroenterology and hepatology department our university hospital for severe diarrhea and abdominal pain. Based on clinical symptoms and biochemical and endoscopic findings, Crohn's disease, intestinal Behçet's disease, and intestinal tuberculosis were considered as differential diagnoses, but a final diagnosis was not reached. Prednisolone, azathioprine, and metronidazole were administered, and no apparent electrolyte abnormality was observed at the patient's admission to our hospital. On the 80th hospital day, marked hypocalcemia, hypophosphatemia, hypokalemia, and hypomagnesemia were noted and prolonged, despite daily supplementation with Ca and inorganic P. At his consultation with our department, we observed decreased fractional excretion of Ca, tubular reabsorption of phosphate, fractional excretion of K, and fractional excretion of Mg, suggesting the depletion of vitamin D and extrarenal wasting of K and Mg. The patient's serum Ca and inorganic P were quickly elevated in response to treatment with an active form of vitamin D, and his serum levels of K and Mg were restored to the normal range by an intravenous administration of K and Mg. A vitamin D deficiency is not rare in inflammatory bowel disease and is caused primarily by the decreased intestinal absorption of vitamin D. In the management of electrolyte imbalances in patients with inflammatory bowel disease, clinicians must consider the possible development of vitamin D deficiency-related disorders.

CONCLUSION

Vitamin D deficiency in entero-Behçet's disease leads to severe hypocalcemia and hypophosphatemia, highlighting the importance of awareness in management.

Role of vitamins A, C, D, E in cancer prevention and therapy: therapeutic potentials and mechanisms of action

Cancer, a leading global cause of mortality, arises from intricate interactions between genetic and environmental factors, fueling uncontrolled cell growth. Amidst existing treatment limitations, vitamins have emerged as promising candidates for cancer prevention and treatment. This review focuses on Vitamins A, C, E, and D because of their protective activity against various types of cancer. They are essential as human metabolic coenzymes. Through a critical exploration of preclinical and clinical studies via PubMed and Google Scholar, the impact of these vitamins on cancer therapy was analyzed, unraveling their complicated mechanisms of action. Interestingly, vitamins impact immune function, antioxidant defense, inflammation, and epigenetic regulation, potentially enhancing outcomes by influencing cell behavior and countering stress and DNA damage. Encouraging clinical trial results have been observed; however, further well-controlled studies are imperative to validate their effectiveness, determine optimal dosages, and formulate comprehensive cancer prevention and treatment strategies. Personalized supplementation strategies, informed by medical expertise, are pivotal for optimal outcomes in both clinical and preclinical contexts. Nevertheless, conclusive evidence regarding the efficacy of vitamins in cancer prevention and treatment is still pending, urging further research and exploration in this compelling area of study.

Effects of Cannabidiol Interactions with CYP2R1, CYP27B1, CYP24A1, and Vitamin D3 Receptors on Spatial Memory, Pain, Inflammation, and Aging in Vitamin D3 Deficiency Diet-Induced Rats

Introduction: The study was planned to investigate memory-enhancing, anti-inflammatory, and antiaging potential of cannabidiol (CBD) on vitamin D3 deficient diet (VDD)-induced rats. Materials and Methods: Cytochrome P-450 enzymes were analyzed by RT-PCR method and others biomarkers by enzyme-linked immunosorbent assay. Results: CYP2R1 and CYP27B1-mRNA were significantly increased by 39.29 and 38.37%, respectively, while; CYP24A1-mRNA was significantly reduced by 21.39% compared to VDD. Vitamin D3 receptor protein expression was significantly increased by 148.3%, 60.48%, and 142.03% in liver, kidney, and brain, respectively, compared to VDD group. Vitamin D3 metabolites and serotonin were significantly increased more than 60% and 100%, respectively, compared to VDD. Spatial memory (in terms of total distance, escape latency) and pain score were improved compared to VDD. Cytokines were significantly reduced than VDD. Besides, levels of superoxide dismutase (49.61%), glutathione peroxidase (178.87%), acetylcholine (25.40%), and klotho (145.57%) were significantly increased than VDD. Conclusions: Study findings supported that CBD interacts with CYP2R1, CYP27B1, CYP24A1, and vitamin D receptors, resulting in increased vitamin D3 metabolites, which improved memory, pain tolerance, reduced inflammation, and aging through modulating antioxidative enzymes, cytokines, and neurotransmitters in VDD-induced rats.

Update on vitamin D status in sunshine-abundant Thailand, 2019-2020

OBJECTIVE

The prevalence of vitamin D deficiency worldwide remains unknown. In the Thai 4th National Health Examination Survey (2008-2009) cohort, ∼45% and 7% of the adult population had serum 25-hydroxyvitamin-D [25(OH)D] levels below the threshold of 75 and 50 nmol/L, respectively. Vitamin D has been a hot topic in the scientific community. The aim of this study was to uncover the current situation regarding vitamin D status in Thailand.

METHODS

Participants were 4098 adults ages 10 to 96 y, randomly selected from the Thai 6th National Health Examination Survey (2019-2020) cohort. Serum 25(OH)D levels were measured by liquid chromatography/tandem mass spectrometry. Data were expressed as mean ± SE and adjusted odds ratio (95% CI).

RESULTS

Mean vitamin D status based on serum 25(OH)D was 88.2 nmol/L and differed by age, sex, residency, and religion. The prevalence of serum 25(OH)D <75 and <50 nmol/L were 31% and 4%, respectively. The prevalence of vitamin D deficiency was lower in individuals who lived in the northeastern part of Thailand or were male. The risk for vitamin D deficiency was lower than that in 2009. In multiple linear regression analysis, female sex, younger age, urbanization, a higher body mass index, Muslim religion, and living in Bangkok or the central region of Thailand were independently associated with lower serum 25(OH)D levels.

CONCLUSIONS

The vitamin D status in the Thai population has improved over the past 10 y. This improvement may reflect an increased awareness related to adequate vitamin D status.

Dietary vitamin D: growth, physiological and health consequences in broiler production

Vitamins are needed in trace amounts in dietary formulations for poultry; however, they are critical for the health, maintenance, and performance of important body organs. Broilers have a lot of leg issues because of their rapid development and lack of exercise. Because of commercial broilers have limited access to direct sunlight, vitamin D supplementation in the feed is critical to reducing the risk of bone deformation and maximizing development. Vitamin D deficiency causes skeletal abnormalities, which may lead also to financial problems. The latest scientific findings on the source, metabolism, mechanisms of action, and functions of vitamin D in broilers are the subject of this review paper.

Serum vitamin D in sanctuary chimpanzees (Pan troglodytes) in range countries: A pilot study

BACKGROUND

Vitamin D is essential for skeletal health, calcium homeostasis and general health. The major and more stable form of vitamin D in circulation is 25-hydroxyvitamin D (25-OH-D); this is the most valuable indicator of vitamin D status. There are studies on laboratory and zoo-housed chimpanzees; however, serum vitamin D status has not been documented in chimpanzees in range countries.

OBJECTIVES

(1) Determine the range of circulating 25-OH-D concentrations in chimpanzees in range countries. (2) Assess the influence of age, sex, and sun exposure on 25-OH-D serum concentrations.

METHODS

Opportunistic blood samples were obtained from 127 clinically healthy chimpanzees. Serum 25-OH-D concentration was measured with a commercially available competitive ELISA.

RESULTS

The median overall 25-OH-D concentration for chimpanzees in range countries was 46.24 nmol/L (range: 17.10-109.23 nmol/L). Males had a significantly lower concentration (40.15 nmol/L) than females (49.61 nmol/L), and infants (37.99 nmol/L) had a significantly lower concentration than adults (46.04 nmol/L). Concentrations of 25-OH-D in chimpanzees in sunnier habitats were significantly higher compared to thick tropical forest habitat.

CONCLUSION

The present constitutes a large dataset of serum 25-OH-D concentrations in range country sanctuary chimpanzees and contributes to document normal ranges. Age, sex, and sun exposure influenced serum concentrations of 25-OH-D in sanctuary chimpanzees.

Circulating vitamin D concentration and risk of 14 cancers: a bidirectional Mendelian randomization study

BACKGROUND

Observational studies have revealed relationships between circulating vitamin D concentrations and the risk of different types of cancer, although the potential causal relationship remains controversial. This study aims to investigate the presence of a causal relationship between circulating vitamin D concentrations and the risk of different types of cancer.

METHODS

Summary statistics from corresponding genome-wide association studies (GWASs) were used to investigate the causal relationship between circulating vitamin D concentrations and the risk of 14 cancers. A two-sample Mendelian randomization (MR) analysis using inverse-variance weighting (IVW) as the primary method was performed. Additionally, the results were verified using four other methods, including MR-Egger, weighted median, weighted mode, and simple mode. Multiple sensitivity analyses were conducted to ensure the robustness of our MR findings.

RESULTS

The MR analysis showed no causal relationship between circulating vitamin D concentrations and most types of cancer, except for a causal relationship with melanoma skin cancer (MSC) (odds ratio [OR]IVW = 1.003, 95% confidence intervals [CI] 1.001-1.005, P = 0.004). Conversely, reverse MR revealed a causal relationship between circulating vitamin D concentration and colorectal cancer (ORIVW = 0.398, 95% CI 0.195-0.813, P = 0.01; ORweighted median = 0.352, 95% CI 0.135-0.917, P = 0.03).

CONCLUSIONS

Our findings provide support for a causal relationship between circulating vitamin D concentration and risk of MSC. Additionally, we found a causal relationship between circulating vitamin D concentration and risk of colorectal cancer in reverse-MR analysis. This evidence indicate that vitamin D is of great significance in the prevention and treatment of MSC and the prognosis of colorectal cancer.

Vitamin D and Cardiovascular Diseases: An Update

Vitamin D is a vital nutrient that plays a significant part in several physiological processes within the human body, including calcium metabolism, bone health, immune function, and cell growth and differentiation. It is obtained mainly through exposure to sunlight but can be acquired from certain foods and supplements as well. Vitamin D deficiency (VDD) could be the risk factor for cardiovascular diseases (CVDs), such as heart disease and stroke. In blood vitamin D low levels have been linked with an enhanced risk of developing CVDs. However, it is unclear whether vitamin D levels are the leading cause or consequence of these conditions. While some studies highlight that taking vitamin D supplements could decrease the risk of CVD; however, more research is required to better understand the association between vitamin D and cardiovascular health. In this review, we aimed to summarize the currently available evidence supporting the association between vitamin D and CVDs and anesthesia considerations.

Antiglycation, antifibrillation and antioxidative effects of para coumaric acid and vitamin D; an in-vitro and in-silico comparative-cum-synergistic approach

Diabetes Mellitus is a metabolic disorder that results in impaired utilization of carbohydrates, lipids, and proteins. Severe hyperglycemia is its principal clinical symptom. Human serum albumin (HSA) is used as a model protein since it is viewed as a sign of glycaemic management because it is more likely to get glycated in diabetic people than other proteins. Para-coumaric acid (pCA), a phenolic acid, and Vitamin D (vit-D) are used as protective agents. In the present work, we deduce a synergistic-cum-comparative effect of pCA and vit-D, expecting some improvement in the efficacy of pCA when combined with vit-D. Methods employed are DPPH radical scavenging activity, In-vitro glycation of HSA, UV-vis spectroscopy, fluorescence analysis, and circular dichroism measurement. After treatment, increasein the absorbance and fluorescence intensity were reduced along with normalization of CD value. . The glycation-mediated fibrillation assessed by Congo-Red and Thioflavin T (ThT) were found to be diminishedwhen HSA was treated with equimolar concentration of p-CA and vit-D- treatment. Fructosamine adduct formation and lysine modificationwas also decreased, while inhibition to hemolysis and lipid peroxidation was found to increase upon treatment. The reactive oxygen species generation detection was also performed in lymphocytes treated with various protein samples. Docking results further confirmed theblocking some glycation-prone amino acids by both compounds. The study shows that the combination in the ratio of 1:1 has provided higher overall protection comparable to aminoguanidine (AG), the molecule which is utilized as a positive control.

Association between serum vitamin D levels and sensitivity to thyroid hormone indices: a cross-sectional observational study in NHANES 2007-2012

Objective

We designed this study to determine whether there is a link between vitamin D levels and sensitivity to thyroid hormone and to provide a new perspective for studying the relationship between vitamin D and thyroid disease.

Methods

Our study included 8,126 participators from the National Health and Nutrition Examination Survey (NHANES) database between 2007 and 2012. We used weighted multiple linear regression models to enquire the connection between serum vitamin D levels and thyroid hormone sensitivity indicators, including the following: Thyroid-stimulating hormone index (TSHI), Free Triiodothyronine/Free thyroxine (FT3/FT4), Thyroid Feedback Quantile-based Index (TFQI), and Thyrotroph Thyroxine Resistance Index (TT4RI). Finally, we used constrained cubic splines to explore possible nonlinear relationships. All data cleaning and statistical analyses were performed using R software.

Results

The final Results were reached after adjusting for various confounding factors. We found a U-shaped relationship between TFQI and serum vitamin D, and the lowest TFQI appeared when the serum vitamin D concentration was 25.77ng/ml. However, an inverse U-shaped relationship was found between FT3/FT4 and vitamin D levels. When the serum vitamin D concentration was 25.43ng/ml, the ratio of FT3/FT4 was the highest.

Conclusion

In the US population, our study concluded that FTQI and FT3/FT4 were U-shaped or inverse-U-shaped with serum vitamin D levels respectively after several adjustments. Therefore, FTQI and FT3/FT4 are considered indicators of the complex relationship between thyroid hormone resistance and vitamin D metabolism. In the future, more complex prospective investigations are needed to confirm these findings and find a causal link between them.

Improvement of vitamin D status through consumption of either fortified food products or supplement pills increased hemoglobin concentration in adult subjects: Analysis of pooled data from two randomized clinical trials

Background: It is documented that vitamin D may have a role in erythropoiesis as its deficiency is accompanied by an increased risk of anemia. Aim: This study aimed to examine whether improvement of vitamin D status through daily consumption of either fortified foods or supplements could impinge on certain hematologic parameters in adults. Methods: We pooled data from our two separate clinical trials and made five experimental groups. As part of their usual diet, one group consumed 500 mL/day of yogurt drink fortified with 1000 IU of vitamin D (D-yogurt, n = 27) whereas one group consumed 500 mL/day of the plain yogurt drink (P-yogurt, n = 27). In addition three other groups consumed either 50 g/day bread fortified with 1000 IU of vitamin D (D-bread) or supplement containing 1000 IU vitamin D (D-supplement, n = 27) or placebo (placebo, n = 27). Biochemical measurements were performed before and after the intervention. Results: In all three vitamin D-supplemented groups, serum 25(OH)D concentration increased after the intervention period, which was interestingly accompanied by a significant increment of hemoglobin (D-yogurt, p < 0.001, D-bread, p = 0.003, D-supplement, p < 0.001). Analyses indicated that among participants in vitamin D-intervention groups, being in D-yogurt group was more favourable predictor of improvement in hemoglobin concentrations compared with the placebo (p < 0.001), D-bread (p = 0.045) and P-yogurt (p = 0.001). Conclusion: Improvement of vitamin D status via regular intake of either vitamin D-fortified food products or supplements can result in a significant increment of hemoglobin in adult subjects. This finding has very important clinical as well as public health implications.

Significance of 25(OH) D3 in Early Dental Implant Failure (EDIF) during osseointegration-A systematic review

Bone metabolism is a key factor for successful osseointegration, and low vitamin D levels may negatively impact the process of osseointegration after implant placement. The study was aimed at evaluating the relation of vitamin D levels with dental implant osseointegration and subsequently the success or failure of the implant. The focused questions were-What is the effect of vitamin D levels on successful dental implant osseointegration and what is the effect of vitamin D supplementation on successful implant osseointegration? A search was conducted on PubMed and Google Scholar using the terms "vitamin D," "cholecalciferol," "1,25(OH) D," "dental implant," "osseointegration," and "bone implant contact" for a period of 10 years from 2011 to 2020. Clinical trials, cross-sectional studies, case series, and case reports were included. A total of ten studies were included after the screening process. Five of these studies evaluated the effect of vitamin D supplementation on osseointegration, whereas five only evaluated the effect of vitamin D deficiency on dental implant osseointegration. Only five of these studies reported dental implant failure varying from 7% to 13% in vitamin D deficient/insufficient groups. Positive relationship exists between serum vitamin D levels and dental implant osseointegration; however, few studies failed to report any relation. More prospective clinical research studies as well as randomized controlled trials are needed to show a significant correlation between decreased serum levels of vitamin D and increased risk of dental implant failure in perspective of vitamin D supplementation which can promote the osseointegration of dental implants.

Benefits of using a microencapsulated vitamin D delivery system in women with polycystic ovary syndrome

OBJECTIVE

To compare and assess the efficacy of two vitamin D delivery systems (oil-based and microencapsulated) on 25-hydroxy-vitamin D (25(OH)D) levels, body mass index (BMI) and insulin resistance (IR) in women with established polycystic ovary syndrome (PCOS) and vitamin D deficiency.

MATERIALS AND METHODS

A monocentric, retrospective study was conducted, using the data of 70 female patients, who visited the endocrinology department of the "Dr. Shterev" Hospital, Sofia, Bulgaria between May 2020 and September 2020. The patients were divided into two groups according to the type of vitamin D3 supplementation: either a microencapsulated liposomal form (n=35), or a conventional oil-based form (n=35). The following clinical measures were analysed and compared: BMI, serum levels of 25(OH)D, fasting plasma glucose levels, fasting immunoreactive insulin (IRI), homeostatic model assessment (HOMA) index, levels of antimullerian hormone (AMH) II generation, and testosterone. In all selected patients, these measurements were performed at baseline and 3 months after initiation of vitamin D supplementation.

RESULTS

Significantly increased serum levels of 25(OH)D were observed in patients supplemented with the microencapsulated form of vitamin D3 in the third month from the beginning of therapy, compared with the control group (p=0.003). In the microencapsulated vitamin D group, there was a decrease in IRI serum levels (p=0.023), HOMA-IR (p=0.021), serum AMH (p=0.010) and testosterone levels (p=0.006). The fasting plasma glucose levels did not change significantly.

CONCLUSION

The results of our study show that the patients supplemented with a microencapsulated form of vitamin D3 achieved faster compensation of 25(OH)D levels, which in turn, under equal conditions, led to significant improvement in the metabolic profile, in particular insulin sensitivity.

2-fluoro-1-methylpyridinium p-toluene sulfonate: a new LC-MS/MS derivatization reagent for vitamin D metabolites

Vitamin D analysis by MS faces several analytical challenges, including inefficient ionization, nonspecific fragmentation, interferences from epimers, isomers, and isobars, as well as very low concentration levels. In this study, we used 2-fluoro-1-methylpyridinium (FMP) p-toluene sulfonate for derivatization of vitamin D3 metabolites to increase detection sensitivity and allow for full chromatographic separation of vitamin D isomers and epimers. UHPLC-MS/MS was used for measurement of five vitamin D3 metabolites in human serum. Compared with Amplifex and 4-phenyl-1,2,4-triazolin-3,5-dion, the FMP p-toluene sulfonate reaction required less time to be performed. The method was optimized and validated to ensure accuracy, precision, and reliability. In-house and commercial quality control samples were used to assure the quality of the results for 25-hydroxyvitamin D3. The method showed very good linearity and intraday and interday accuracy and precision; coefficients of determination (r2) ranged between 0.9977 and 0.9992, relative recovery from 95 to 111%, and coefficient of variation from 0.9 to 11.3. Stability tests showed that the extracted derivatized serum samples were stable for 24 h after storage at -20°C; 24,25-dihydroxyvitamin D3 and 1,25-dihydroxyvitamin D3-FMP derivatives were stable for 1 week at -80°C. The method was applied to samples of healthy individuals for quantitative determination of vitamin D3, the two epimers of 25-hydroxyvitamin D3 and 24,25-dihydroxyvitamin D3.

The role of nutraceuticals in heart failure muscle wasting as a result of inflammatory activity. The International Lipid Expert Panel (ILEP) Position Paper

Muscle wasting is one of the main causes for exercise intolerance and ventilatory inefficiency in patients with heart failure and a strong predictor of frailty and reduced survival. The prevalence of sarcopenia is at least 20% in patients with heart failure. Patients with heart failure often have subclinical systemic inflammation, which may exert sustained effects on skeletal muscle. Besides exercise, nutrition should also be carefully evaluated as an appropriate diet with selected nutraceuticals may be able to stimulate muscle anabolism and inhibit muscle catabolism. This review summarizes the epidemiological and clinical trial evidence supporting the recommendations for the use of nutraceuticals with anti-inflammatory properties in heart failure and provides an overview of the state of the evidence for nutraceutical supplementation to prevent and/or mitigate heart failure muscle wasting.

Mass Sportrometry: An annual look back at applications of mass spectrometry in sport and exercise science

Research in sport and exercise science (SES) is reliant on robust analyses of biomarker measurements to assist with the interpretation of physiological outcomes. Mass spectrometry (MS) is an analytical approach capable of highly sensitive, specific, precise, and accurate analyses of a range of biomolecules, many of which are of interest in SES including, but not limited to, endogenous metabolites, exogenously administered compounds (e.g. supplements), mineral ions, and circulating/tissue proteins. This annual review provides a summary of the applications of MS across studies investigating aspects related to sport or exercise in manuscripts published, or currently in press, in 2022. In total, 93 publications are included and categorized according to their methodologies including targeted analyses, metabolomics, lipidomics, proteomics, and isotope ratio/elemental MS. The advantageous analytical opportunities afforded by MS technologies are discussed across a selection of relevant articles. In addition, considerations for the future of MS in SES, including the need to improve the reporting of assay characteristics and validation data, are discussed, alongside the recommendation for selected current methods to be superseded by MS-based approaches where appropriate. The review identifies that a targeted, mostly quantitative, approach is the most commonly applied MS approach within SES, although there has also been a keen interest in the use of 'omics' to perform hypothesis-generating research studies. Nonetheless, MS is not commonplace in SES at this time, but its use to expand, and possibly improve, the analytical options should be continually considered to exploit the benefits of analytical chemistry in exercise/sports-based research. Overall, it is exciting to see the gradually increasing adoption of MS in SES and it is expected that the number, and quality, of MS-based assays in SES will increase over time, with the potential for 2023 to further establish this technique within the field.

Assessment of Serum Vitamin D Status and Its Associated Health Problem Among Children With Protein Energy Malnutrition: A Cross-Sectional Research Study in Central Rural India

Background Protein energy malnutrition (PEM) is a condition that results from inadequate intake of both macronutrients and micronutrients, leading to a lack of energy. The condition can manifest quickly or gradually, ranging from mild to severe. It predominantly affects children in low-income countries who do not receive enough calories and proteins. In developed nations, it is more prevalent among older individuals. PEM is more common in children as they consume less protein. In rare cases in developed countries, it may result from fad diets or a lack of knowledge about children's nutritional requirements, especially in cases of milk allergy. Vitamin D plays a critical role in bone growth and development by facilitating the absorption of calcium and phosphorus from food and supplements. Additionally, vitamin D has been linked to a reduced risk of infections, immune system disorders, diabetes, high blood pressure, and heart disease. Aims and objectives The primary objective of this study is to evaluate serum vitamin D levels and their relationship with health complications in children affected by PEM. The specific aim is to estimate the serum vitamin D levels in children with PEM who exhibit symptoms of being underweight, stunting (limited linear growth), wasting (abrupt weight loss), or edematous malnutrition (kwashiorkor). Additionally, this study seeks to analyze the correlation between serum vitamin D levels and the associated health problems in children with PEM. Materials and methods This cross-sectional study employed an analytical research approach. A total of 45 children with PEM participated in the study. Data were collected through a venipuncture method, and serum vitamin D level was assessed using an enhanced chemiluminescence method. The children's pain was assessed using a visual analogue scale, and developmental delay was evaluated using an assessment chart. Data were analyzed using SPSS Version 22 (IBM Corp., Armonk, NY). Results The study's results indicate that a considerable proportion of children, specifically 46.6%, were deficient in vitamin D, whereas 42.2% exhibited insufficiency and only 11.2% had sufficient levels of the vitamin. Pain assessment using the visual analogue scale classification revealed that 15.6% of children reported no pain, 60% reported mild pain, and 24.4% reported moderate pain. The mean and standard deviation of vitamin D levels correlated with developmental delay were 4.22±0.212 and 5.34±0.438, respectively. Similarly, the mean and standard deviation of vitamin D levels correlated with pain were 4.22±0.212 and 2.98±0.489, respectively. The Pearson correlation coefficient for vitamin D levels and pain was 0.010, with a significant level of 0.989, significantly lower than the tabulated value at a 5% significance level. Conclusion Based on the study's findings, it was concluded that children who suffer from PEM are at a risk of developing vitamin D deficiency, which can result in adverse health outcomes, including developmental delay and pain.

Vitamin D in pediatric age: Current evidence, recommendations, and misunderstandings

In recent years vitamin D has been in the spotlight of many researchers for its possible role in various disorders, including autoimmune and infectious diseases. Even if vitamin D deficiency remains a major public health problem, its symptomatic manifestations are less and less common in clinical practice, and pediatric age represents a “gray area” where vitamin D supplementation is often administered in the absence of an effective evaluation of its status. Moreover, a poor knowledge about different definitions of “deficiency,” “insufficiency,” and similar terms is spread among clinicians, while guidelines are not univocal, especially after the first year of life. The aim of this brief opinion paper is to sum up recent evidence about vitamin D status and its supplementation in pediatrics, in order to better clarify a common definition of its deficiency. The aim of this opinion article is to raise awareness on this topic among clinicians and encourage a discussion on the real need for routine 25-hydroxycholecalciferol serum evaluation and its supplementation.

Quantification of 25-hydroxyvitamin D2 and D3 in Mitra® devices with volumetric absorptive microsampling technology (VAMS®) by UHPLC-HRMS for regular vitamin D status monitoring

The numbers of vitamin D inadequacies has reportedly increased in the general population, especially in the Northern hemisphere. However, routine measurement of 25(OH) vitamin D is usually associated with a substantial effort due to the requirement of a venous blood sample taken by medical professionals. Thus, the objective of this work is to develop and validate an easy and minimal-invasive method, using a microsampling technique for autonomous blood collections by medically untrained individuals. The assay enables a simplified monitoring of the vitamin D-status in both, risk group and normal population throughout the year. For this purpose, a simple methanol extraction without derivatization combined with a UHPLC-HRMS method was developed to quantify 25(OH)D2 and 25(OH)D3 in capillary blood. For sample collection, a 20 μl Mitra® device with VAMS® technology is used. By employing the six-fold deuterium-labelled 25(OH)D3 as internal standard, the validated assay provides accurate (<10%) and precise (<11%) results. With a LOQ of 5 ng/ml, the approach also proved sensitive enough to adequately identify potential vitamin D deficiencies (< 12 ng/ml), and proof-of-concept analyses of authentic VAMS® samples (n = 20) yielded test results in the expected blood concentration range. Implementing VAMS® sampling for vitamin D-status monitoring enables a higher frequency due to a simplified, straightforward, and time-effective sample collection. VAMS® assures accurate sample volumes because of its absorptive capacities and, thus, area bias and homogeneity issues associated with conventional DBS are avoided. Regular monitoring of 25(OH)D status throughout the year supports people in high-risk groups for vitamin D-deficiency by early identifying inadequacies and, thus, preventing adverse health consequences.

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.

The Association between Self-Rated Health Status, Psychosocial Stress, Eating Behaviors, and Food Intake According to the Level of Sunlight Exposure in Korean Adults

Sunlight exposure has been reported to have various beneficial effects on human health. This study investigated the relationship between self-rated health status, psychosocial stress, eating behaviors, and food intake according to sunlight exposure in 948 adults. Sunlight exposure was classified as less than one hour, less than three hours, and greater than three hours. Of the participants, 49.2% had fewer than three hours of daily exposure to sunlight. Regarding participants exposed to sunlight for less than one hour, the largest response was that they did not engage in outdoor activities on weekdays or weekends, and the rate of being outdoors in the shade on sunny days was the highest in this group at 42.7%. Furthermore, the participants exposed to sunlight for less than one hour had a lower health response than the other two groups, and there were significantly more participants classified in the stress risk group. Regarding eating habits, those with less than an hour of exposure to sunlight frequently ate fried foods, fatty foods, added salt, and snacks, and had significantly lower total dietary scores or three regular meals. Additionally, their frequency of consumption of cereals, milk and dairy products, orange juice, and pork was also significantly lower than the other groups. Thus, it is necessary to provide sufficient guidelines for adequate sunlight exposure and food intake because participants with low sunlight exposure may have low vitamin D synthesis and insufficient food intake.

Knowledge and Attitudes towards Vitamin D among Health Educators in Public Schools in Jeddah, Saudi Arabia: A Cross-Sectional Study

Health educators in schools are a very important part of the education system. Considering the significant prevalence of vitamin D deficiency in the Kingdom of Saudi Arabia, it is important to investigate the knowledge of and attitude towards vitamin D among health educators. This study aims to examine the knowledge of and attitude towards vitamin D among health educators in public schools in Jeddah as well as to identify the associated sociodemographic factors. A cross-sectional study was conducted between May and December 2021 among 231 health educators. Data were collected via a self-administered online questionnaire. The results revealed that only 45% of health educators had good knowledge of vitamin D, and approximately 43% had a positive attitude towards vitamin D. Additionally, those who had good knowledge of vitamin D were males (58.7%) (p = 0.005) and had a bachelor's degree (74%) (p = 0.01). Moreover, male health educators aged 45-54 years had a positive attitude towards vitamin D (3.8 ± 0.7) (p = 0.007). In addition, female health educators who were divorced (3.8 ± 0.7) and widowed (3.6 ± 0.5) (p = 0.04) and those who were administrators (3.3 ± 0.7) (p = 0.01) had a positive attitude towards vitamin D. The Ministry of Education (MOE) in the Kingdom must educate health educators through educational programmes that aim to increase the knowledge of and develop a positive attitude towards vitamin D intake.

Effects of Vitamin D on Satellite Cells: A Systematic Review of In Vivo Studies

The non-classical role of vitamin D has been investigated in recent decades. One of which is related to its role in skeletal muscle. Satellite cells are skeletal muscle stem cells that play a pivotal role in skeletal muscle growth and regeneration. This systematic review aims to investigate the effect of vitamin D on satellite cells. A systematic search was performed in Scopus, MEDLINE, and Google Scholar. In vivo studies assessing the effect of vitamin D on satellite cells, published in English in the last ten years were included. Thirteen in vivo studies were analyzed in this review. Vitamin D increases the proliferation of satellite cells in the early life period. In acute muscle injury, vitamin D deficiency reduces satellite cells differentiation. However, administering high doses of vitamin D impairs skeletal muscle regeneration. Vitamin D may maintain satellite cell quiescence and prevent spontaneous differentiation in aging. Supplementation of vitamin D ameliorates decreased satellite cells' function in chronic disease. Overall, evidence suggests that vitamin D affects satellite cells' function in maintaining skeletal muscle homeostasis. Further research is needed to determine the most appropriate dose of vitamin D supplementation in a specific condition for the optimum satellite cells' function.

The synergistic effects of short inter-pregnancy interval and micronutrients deficiency on third-trimester depression

Objective

To explore the effect of inter-pregnancy interval (IPI) and micronutrients on depression in the third trimester of pregnancy.

Materials and methods

A total of 5,951 eligible pregnant women were included in this single-center retrospective cohort study. Variables with potential effects on third-trimester depression were collected. These variables included: maternal factors [age, pregnancy interval, body mass index (BMI), BMI change, gravidity, native place, education, smoking, and alcohol consumption], previous delivery outcomes [preterm birth, preeclampsia, intrahepatic cholestasis of pregnancy (ICP), gestational diabetes mellitus (GDM), fetal growth restriction (FGR), and delivery mode], and micronutrients in early pregnancy (folic acid, 25-hydroxy vitamin D, vitamin B12, calcium, and ferritin). Univariate and multivariate analyses were used to screen the factors affecting the occurrence of depression. Based on these factors, the nomogram model was established. At the same time, the interaction between IPI and micronutrients was verified.

Results

The incidence of depression in the third trimester of pregnancy was 4.3%. Univariate and multivariate analysis showed that there were five independent risk factors for third-trimester depression: gravidity, previous cesarean section delivery, folic acid, and vitamin D levels in early pregnancy and IPI. According to the multivariate logistic regression analysis, the prediction model and nomogram were established. The prediction cut-offs of the corresponding factors were calculated according to the Youden index. Finally, the synergistic effect of short IPI and micronutrient deficiency was verified.

Conclusion

There is a synergistic effect between short IPI and micronutrient deficiency in early pregnancy, which can aggravate the occurrence of depression in late pregnancy.

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 Exerts Significant Antitumor Effects by Suppressing Vasculogenic Mimicry in Breast Cancer Cells

Background

Numerous clinical and experimental observations have alluded to the substantial anti-neoplastic role of vitamin D in breast cancer (BC), primarily by inducing apoptosis and affecting metastasis. Tumor progression and resistance to chemotherapy have been linked to vasculogenic mimicry (VM), which represents the endothelial-independent formation of microvascular channels by cancer cells. However, the effect of vitamin D on VM formation in BC has not been thoroughly investigated. This study examined the impact of 1α,25-dihydroxyvitamin D3 (calcitriol), the active form of vitamin D, on the expression of major factors involved in BC migration, invasion, and VM formation.

Experimental Methods

Publicly available transcriptomic datasets were used to profile the expression status of the key VM markers in vitamin D-treated BC cells. The in silico data were validated by examining the expression and activity of the key factors that are involved in tumor progression and MV formation in hormone-positive MCF-7 and aggressive triple‐negative MDA-MB-231 BC cells after treatment with calcitriol.

Results and Discussions

The bioinformatics analysis showed that tumor VM formation-enriched pathways were differentially downregulated in vitamin D-treated cells when compared with control counterparts. Treatment of BC cells with calcitriol resulted in increased expression of tissue inhibitors of metalloproteinases (TIMPs 1 and 2) and decreased content and gelatinolytic activity of matrix metalloproteinases (MMPs 2 and 9). Furthermore, calcitriol treatment reduced the expression of several pro-MV formation regulators including vascular endothelial growth factor (VEGF), tumor growth factor (TGF-β1), and amphiregulin. Eventually, this process resulted in a profound reduction in cell migration and invasion following the treatment of BC cells with calcitriol when compared to the controls. Finally, the formation of VM was diminished in the aggressive triple‐negative MDA-MB-231 cancer cell line after calcitriol treatment.

Conclusion

Our findings demonstrate that vitamin D mediates its antitumor effects in BC cells by inhibiting and curtailing their potential for VM formation.

ASSOCIATION BETWEEN VITAMIN D STATUS AND PHYSICAL PERFORMANCE IN COVID-19 SURVIVORS: RESULTS FROM THE GEMELLI AGAINST COVID-19 POST-ACUTE CARE PROJECT

Aim

To determine the prevalence and associated factors of vitamin D deficiency in COVID-19 survivors and the relationship between vitamin D status and physical performance.

Methods

Vitamin D status was assessed in a sample of patients who had recovered from COVID-19 and were admitted to a post-acute outpatient service at the Fondazione Policlinico Universitario Agostino Gemelli IRCCS (Rome, Italy). Participants were offered comprehensive medical assessment, including physical performance and muscle strength tests. Self-rated health was assessed. Vitamin D deficiency was defined as a serum concentration of 25-OH vitamin D < 20 ng/mL.

Results

Mean age of 681 participants was 53.4 ± 15.2 years and 49% were women. Vitamin D deficiency was detected in 35.6% of the whole study population, and in 40.2% of those 65 and older. Vitamin D deficiency was associated with diabetes, higher body mass index, and COVID-19 severity, and showed a seasonal pattern with a peak in autumn/winter. Participants with vitamin D deficiency performed poorer on the six-minute walking test, with the lowest performance observed in those 65 and older. No significant associations with any other parameters were found.

Conclusion

Our findings indicate that vitamin D deficiency is frequent in COVID-19 survivors, especially in older adults. Low vitamin D levels are associated with poor physical performance, in particular in old age.

An ultrasensitive UHPLC-ESI-MS/MS method augmented with a controlled microwave derivatization reaction for quantitation of vitamin D3 and its major metabolites in COVID-19 patients

It is established that vitamin D deficiency is correlated with the disease severity in COVID-19 patients. However, the reliable and sensitive quantitation of vitamin D3 (D3) and its metabolites remains a difficult challenge. Herein, a novel ultrasensitive and reliable UHPLC-ESI-MS/MS method was developed and validated for the quantitation of D3 and its major metabolites in COVID-19 patients. The mass spectral sensitivity was augmented via controlled microwave-assisted derivatization reaction (CMDR) with 2-nitrosopyridine (Pyr-NO) at 65 °C for 2 min. CMDR hyphenation with UHPLC-MS/MS improves detection sensitivity while shortening separation and derivatization reaction times. The precursor to product ion transitions for D3, 25-hydroxy D3 (25(OH)D3), 1,25-dihydroxy D3 (1,25-(OH)2D3) and calcipotriol (CPT) as an internal standard were m/z 493.4 → 231.3, m/z 509.4 → 231.3, m/z 525.4 → 247.3, and m/z 521.4 → 247.3; respectively. The separation of the formed derivatives was conducted using a gradient elution mode with mobile phase A: formic acid (0.1%) in water and mobile phase B: formic acid (0.1%) in acetonitrile. The elution started with 40% (v/v) of B for 0.3 min then increased linearly to 90% (v/v) at 2 min on an Agilent EclipsePlus C18 (50 × 2.1 mm, 1.8 μm) column at a flow rate of 0.3 mL min⁻¹. The method was validated using FDA standards for bioanalytical method validation over a concentration range of 0.02–50 ng mL⁻¹ with correlation coefficient ≥0.9987 and the lower limit of quantitation (LLOQ) were 0.02–0.05 ng mL⁻¹ in human plasma. The developed method has demonstrated excellent comparability to a well-established chemiluminescent immunoassay (CLIA) method for the analysis of D3 metabolites in human samples. The developed UHPLC-ESI-MS/MS method was implemented for routine and reliable quantitation of D3 and its major metabolites in COVID-19 patients.

Nanocarriers for Drug Delivery: An Overview with Emphasis on Vitamin D and K Transportation

Mounting evidence shows that supplementation with vitamin D and K or their analogs induces beneficial effects in various diseases, e.g., osteoarticular, cardiovascular, or carcinogenesis. The use of drugs delivery systems via organic and inorganic nanocarriers increases the bioavailability of vitamins and analogs, enhancing their cellular delivery and effects. The nanotechnology-based dietary supplements and drugs produced by the food and pharmaceutical industries overcome the issues associated with vitamin administration, such as stability, absorption or low bioavailability. Consequently, there is a continuous interest in optimizing the carriers' systems in order to make them more efficient and specific for the targeted tissue. In this pioneer review, we try to circumscribe the most relevant aspects related to nanocarriers for drug delivery, compare different types of nanoparticles for vitamin D and K transportation, and critically address their benefits and disadvantages.

Vitamin D and Ocular Diseases: A Systematic Review

The contributory roles of vitamin D in ocular and visual health have long been discussed, with numerous studies pointing to the adverse effects of vitamin D deficiency. In this paper, we provide a systematic review of recent findings on the association between vitamin D and different ocular diseases, including myopia, age-related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), dry eye syndrome (DES), thyroid eye disease (TED), uveitis, retinoblastoma (RB), cataract, and others, from epidemiological, clinical and basic studies, and briefly discuss vitamin D metabolism in the eye. We searched two research databases for articles examining the association between vitamin D deficiency and different ocular diseases. One hundred and sixty-two studies were found. There is evidence on the association between vitamin D and myopia, AMD, DR, and DES. Overall, 17 out of 27 studies reported an association between vitamin D and AMD, while 48 out of 54 studies reported that vitamin D was associated with DR, and 25 out of 27 studies reported an association between vitamin D and DES. However, the available evidence for the association with other ocular diseases, such as glaucoma, TED, and RB, remains limited.

Combined Maternal and Post-Hatch Dietary Supplementation of 25-Hydroxycholecalciferol Alters Early Post-Hatch Broiler Chicken Duodenal Macrophage and Crypt Cell Populations and Their Mitotic Activity

The previous work has demonstrated that maternal supplementation of the circulating metabolite of vitamin D3 (D3), 25-hydroxycholecalciferol (25OHD3), enhances the immunocompetence of broiler chick offspring. In post-hatch broiler diets, 25OHD3 has been shown to affect intestinal morphology and improve the immune status of broilers. An experiment with a 2 × 2 factorial treatment arrangement was conducted to assess the effects of combining maternal (MDIET) and post-hatch (PDIET) dietary 25OHD3 inclusion on duodenal crypt and macrophage cell populations and mitotic activity in young broiler chickens. All diets were formulated to provide 5,000 IU of vitamin D. Broiler breeder hens were offered 1 of 2 MDIET: 5,000 IU D3 per kg of feed (MCTL) or 2,240 IU of D3 + 2,760 IU of 25OHD3 per kg of feed (M25OHD3) from week 25 to 41. Male broiler offspring (n = 480) hatched from eggs collected during week 41 of breeding age were allotted in raised floor pens (4 birds per pen from day 0 to 7 and individually allotted from day 8 to 21). Chicks were fed 1 of 2 PDIET (starter day 0 to 21): 5,000 IU D3 per kg of feed (PCTL) or 2,240 IU D3 + 2,760 IU 25OHD3 (P25OHD3). DUO samples (n = 12 birds per treatment per day) were collected on days 3, 6, 9, 12, 15, 18, and 21 for cryohistological and immunofluorescence analysis to facilitate the enumeration of the total macrophages, CD80+ macrophages (pro-inflammatory macrophages), and mitotically active cells (BrdU+) to calculate the proportion of proliferating cells (PPC) per duodenal crypt. Bird age impacted crypt PPC with the greatest PPC per duodenal crypt observed on days 3 and 9, and the lowest PPC per crypt was observed on day 21 (P < 0.0001). Broilers from the M25OHD3:PCTL treatment had a greater PPC (P =.002) than birds from the MCTL:PCTL treatment at day 3. An interaction among MDIET and PDIET was observed for proliferating macrophages at day 21 (P = 0.029) where M25OHD3:P25OHD3 birds had more proliferating macrophages than M25OHD3:PCTL-fed birds. These results indicate that combined MDIET and PDIET 25OHD3 supplementation may alter early post-hatch duodenal development and innate immunity.

Lower Blood Vitamin D Levels Are Associated with Depressive Symptoms in a Population of Older Adults in Kuwait: A Cross-Sectional Study

Low serum vitamin D has been associated with an increased risk of neuropsychiatry disorders. This study aimed to examine the association between vitamin D deficiency and depression in adults aged 65 years and older. This cross-sectional study was conducted in seven primary healthcare centers across Kuwait (November 2020 to June 2021). The participants (n = 237) had their serum vitamin D 25-(OH)-D concentrations (analyzed by LC-MS) classified as sufficient, ≥75 nmol/L (30 ng/mL); insufficient, 50−75 nmol/L (20−30 ng/mL); or deficient, <50 nmol/L (20 ng/mL). Depressive symptoms were evaluated using the 15-Item Geriatric Depression Scale (15-item GDS). The mean serum 25-OH-D levels (nmol/L) in volunteers with normal, mild, moderate, and severe depression were 100.0 ± 31.7, 71.2 ± 38.6, 58.6 ± 30.1 and 49.0 ± 6.93, respectively (p < 0.001). The participants in the vitamin D sufficiency group were significantly less likely to exhibit depressive symptoms (88.2%) than patients with mild (36%) and moderate (21%) depression (p < 0.001). Ordinal logistic regression showed that vitamin D deficiency (OR = 19.7, 95% CI 5.60, 74.86, p < 0.001) and insufficiency (OR = 6.40, 95% CI 2.20, 19.91, p < 0.001) were associated with higher odds of having depressive symptoms. A low serum vitamin D level is a significant predictor of symptoms of depression among older individuals.

Vitamin D and Hypoxia: Points of Interplay in Cancer

Vitamin D is a hormone that, through its action, elicits a broad spectrum of physiological responses ranging from classic to nonclassical actions such as bone morphogenesis and immune function. In parallel, many studies describe the antiproliferative, proapoptotic, antiangiogenic effects of calcitriol (the active hormonal form) that contribute to its anticancer activity. Additionally, epidemiological data signify the inverse correlation between vitamin D levels and cancer risk. On the contrary, tumors possess several adaptive mechanisms that enable them to evade the anticancer effects of calcitriol. Such maladaptive processes are often a characteristic of the cancer microenvironment, which in solid tumors is frequently hypoxic and elicits the overexpression of Hypoxia-Inducible Factors (HIFs). HIF-mediated signaling not only contributes to cancer cell survival and proliferation but also confers resistance to anticancer agents. Taking into consideration that calcitriol intertwines with signaling events elicited by the hypoxic status cells, this review examines their interplay in cellular signaling to give the opportunity to better understand their relationship in cancer development and their prospect for the treatment of cancer.