Vitamin D and bone

Dairy and Exercise for Bone Health: Evidence from Randomized Controlled Trials and Recommendations for Future Research

PURPOSE OF REVIEW

To examine evidence from randomized controlled trials (RCTs) on how modifiable factors such as exercise and nutrition, with a focus on dairy products, play a role in improving bone health across the lifespan.

RECENT FINDINGS

Meta-analyses of RCTs demonstrate the advantages of consuming dairy products to improve bone mineral density/content (BMD/BMC) and markers of bone metabolism and turnover (BTMs). Eighteen RCTs were conducted investigating the combined effects of dairy and exercise, with most indicating a benefit in youth and adult populations. Results were less conclusive in older adults, perhaps due to altered requirements for dairy/nutrients and exercise with increased age.   RCTs demonstrate that dairy product consumption alone benefits bone health and can enhance the effects of exercise on bone. This may help improve skeletal growth and development in adolescence and prevent osteoporosis with increased age. Future RCTs should account for habitual nutrient intakes, and dairy dosage, timing, and matrix effects.

Prevalence and Risk Factors of Vitamin D Deficiency in Patients Scheduled to Undergo Revision Arthroplasty of the Hip, Knee and Shoulder-Data from a Single-Centre Analysis

Vitamin D is crucial for ideal bone health and good muscle function, both essential requirements for successful joint arthroplasty. Hence, vitamin D deficiency has recently been identified as a predictor of poorer outcomes in patients scheduled to undergo total joint arthroplasty (TJA). Moreover, there is ample evidence today that vitamin D deficiency is associated with periprosthetic joint infection. Yet, vitamin D deficiency seems to be frequent in patients who are scheduled to undergo TJA. However, the prevalence of hypovitaminosis D in patients who require revision arthroplasty (rTJA) is largely unknown. Further, risk factors of vitamin D deficiency in these patients remain to be elucidated. For this reason, the primary objective of this study was to assess the vitamin D status of patients scheduled to undergo rTJA of the hip, knee and shoulder. The secondary objective was to identify potential risk factors for hypovitaminosis D in these patients. Serum vitamin D [25(OH)D] levels of 249 patients who were scheduled for rTJA were assessed over a period of twelve months at a high-volume TJA centre. Collectively, 23% of patients reported a routine intake of vitamin D supplements (58/249). Notably, 81% of patients (155/191) who did not report a routine vitamin D intake presented with insufficient vitamin D levels (below 30 ng/mL), while only 19% of patients (36/191) had sufficient vitamin D levels. Of those who reported a routine vitamin D intake, 75% (43/58) had sufficient vitamin D levels, while 25% (15/58) showed insufficient vitamin D status. Patients who did not routinely take any vitamin D supplements had significantly lower vitamin D levels compared to patients who reported regular vitamin D intake (19.91 ng/mL vs. 40.66 ng/mL). Further, BMI and nicotine abuse were identified as potential risk factors for hypovitaminosis D in patients without vitamin D supplementation. Moreover, the season of spring seems to be a risk factor in patients with vitamin D supplementation, while age itself did not appear to be a significant risk factor for low vitamin D levels. In conclusion, we found an alarmingly high rate of vitamin D deficiency in patients scheduled to undergo rTJA. Notably, reported routine vitamin D supplementation showed significantly increased serum vitamin D levels compared to patients with no reported supplementation. Due to the high prevalence of vitamin D deficiency, we believe that vitamin D status should routinely be assessed in patients who are scheduled to undergo rTJA.

Assessment of Supplementation with Different Biomolecules in the Prevention and Treatment of COVID-19

Consequences of the disease produced by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have led to an urgent search for preventive and therapeutic strategies. Besides drug treatments, proposals have been made for supplementation with biomolecules possessing immunomodulatory and antioxidant properties. The objective of this study was to review published evidence on the clinical usefulness of supplementation with vitamin D, antioxidant vitamins (vitamin A, vitamin E, and vitamin C), melatonin, lactoferrin and natural products found in food (curcumin, luteolin, ginger, allicin, magnesium and zinc) as supplements in SARS-CoV-2 infection. In general, supplementation of conventional treatments with these biomolecules has been found to improve the clinical symptoms and severity of the coronavirus disease (COVID-19), with some indications of a preventive effect. In conclusion, these compounds may assist in preventing and/or improving the symptoms of COVID-19. Nevertheless, only limited evidence is available, and findings have been inconsistent. Further investigations are needed to verify the therapeutic potential of these supplements.

QSTR Models in Dioxins and Dioxin-like Compounds Provide Insights into Gene Expression Dysregulation

Polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans (PCDD/Fs) are a group of organic chemicals containing three-ring structures that can be substituted with one to eight chlorine atoms, leading to 75 dioxin and 135 furan congeners. As endocrine-disrupting chemicals (EDCs), they can alter physiological processes causing a number of disorders. In this study, quantitative structure-toxicity relationship (QSTR) studies were used to determine the correlations between the PCDD/Fs' molecular structures and various toxicity endpoints. Strong QSTR models, with the coefficients of determination (r2) values greater than 0.95 and ANOVA p-values less than 0.0001 were established between molecular descriptors and the endpoints of bioconcentration, fathead minnow LC50, and Daphnia magna LC50. The ability of PCDD/Fs to bind to several nuclear receptors was investigated via molecular docking studies. The results show comparable, and in some instances better, binding affinities of PCDD/Fs toward the receptors relative to their natural agonistic and antagonistic ligands, signifying possible interference with the receptors' natural biological activities. These studies were accompanied by the molecular dynamics simulations of the top-binding PCDD/Fs to show changes in the receptor-ligand complexes during binding and provide insights into these compounds' ability to interfere with transcription and thereby modify gene expression. This introspection of PCDD/Fs at the molecular level provides a deeper understanding of these compounds' toxicity and opens avenues for future studies.

Vitamin D administration increases serum alanine concentrations in thermally injured mice

Thermal or burn injury results in profound metabolic changes in the body. This can contribute to muscle atrophy, bone loss, as well as suppression of the immune system. While the mechanisms that underlie this hypermetabolic response remain unclear, patients with burn injury often have low circulating levels of vitamin D. Vitamin D has been shown to regulate bone formation as well as regulate muscle function. We sought to clarify the effects of vitamin D administration on skeletal muscle function following thermal injury using a mouse model. We found that thermal injury resulted in decreased vitamin D levels as well as decreased bone mineral density. Branched chain amino acid (BCAA)s levels were also significantly enhanced in the serum following burn injury. Vitamin D administration reversed the decrease in bone marrow-derived mesenchymal stem cell (BM-MSC)s observed post burn injury. Interestingly, vitamin D administration also resulted in increased tricarboxylic acid cycle (TCA) cycle metabolites in muscle which was decreased after burn conditions, enhanced the supply of alanine and glutamine in the blood which could contribute to gluconeogenesis and wound healing. Therefore, vitamin D supplementation after burn injury may have effects not only in bone metabolism, but may affect substrate metabolism in other organs/tissues.

The Relationship of Low-Serum Vitamin D and Early Dental Implant Failure

The study is aimed to assess the effects of serum vitamin D levels and their relationship to early dental implant failures. A total of 174 implants in 109 patients were placed and serum vitamin D levels were noted on the day of implant placement. Implants were followed up until restoration, approximately 3-6 months later, and any implant failure was reported based on 50% or more bone loss or implant mobility. Eight individuals had an implant fail early and their vitamin D levels had a mean of 42.54 ng/mL compared with the successful patients' levels of 31.92 ng/mL. Although not statistically significant, there was no correlation between patients' low serum vitamin D levels and early implant failure.

Physiology of Vitamin D-Focusing on Disease Prevention

Vitamin D is a crucial micronutrient, critical to human health, and influences many physiological processes. Oral and skin-derived vitamin D is hydroxylated to form calcifediol (25(OH)D) in the liver, then to 1,25(OH)2D (calcitriol) in the kidney. Alongside the parathyroid hormone, calcitriol regulates neuro-musculoskeletal activities by tightly controlling blood-ionized calcium concentrations through intestinal calcium absorption, renal tubular reabsorption, and skeletal mineralization. Beyond its classical roles, evidence underscores the impact of vitamin D on the prevention and reduction of the severity of diverse conditions such as cardiovascular and metabolic diseases, autoimmune disorders, infection, and cancer. Peripheral target cells, like immune cells, obtain vitamin D and 25(OH)D through concentration-dependent diffusion from the circulation. Calcitriol is synthesized intracellularly in these cells from these precursors, which is crucial for their protective physiological actions. Its deficiency exacerbates inflammation, oxidative stress, and increased susceptibility to metabolic disorders and infections; deficiency also causes premature deaths. Thus, maintaining optimal serum levels above 40 ng/mL is vital for health and disease prevention. However, achieving it requires several times more than the government's recommended vitamin D doses. Despite extensive published research, recommended daily intake and therapeutic serum 25(OH)D concentrations have lagged and are outdated, preventing people from benefiting. Evidence suggests that maintaining the 25(OH)D concentrations above 40 ng/mL with a range of 40-80 ng/mL in the population is optimal for disease prevention and reducing morbidities and mortality without adverse effects. The recommendation for individuals is to maintain serum 25(OH)D concentrations above 50 ng/mL (125 nmol/L) for optimal clinical outcomes. Insights from metabolomics, transcriptomics, and epigenetics offer promise for better clinical outcomes from vitamin D sufficiency. Given its broader positive impact on human health with minimal cost and little adverse effects, proactively integrating vitamin D assessment and supplementation into clinical practice promises significant benefits, including reduced healthcare costs. This review synthesized recent novel findings related to the physiology of vitamin D that have significant implications for disease prevention.

Impact of particulate-matter air pollution on 25-hydroxyvitamin D levels: a mendelian randomisation study

OBJECTIVES

In observational studies, the 25-hydroxyvitamin D (25(OH)D) level in body has been found to be closely related to particulate matter (PM) air pollution. In this study, we used the two-sample mendelian randomisation (MR) method to investigate and discuss the potential causal relationship and mode of influence.

STUDY DESIGN

MR study.

METHODS

PM data (PM10, PM2.5-10, PM2.5, PM2.5 absorbance) came from the UK Biobank database, and 25(OH)D data came from European Bioinformatics Institute (EBI) database. The analysis was conducted utilising three prominent methods (inverse-variance-weighted [IVW], MR-Egger, weighted median, weighted mode, and simple mode). The primary emphasis was placed on IVW, accompanied by heterogeneity and horizontal pleiotropy tests. Furthermore, sensitivity analysis was undertaken.

RESULTS

The MR analysis revealed a significant association between exposure to PM10 and a decrease in levels of 25(OH)D (odds ratio [OR]: 0.878, 95% confidence interval [CI]: 0.789-0.977). However, no significant relationship was observed between PM2.5 exposure and 25(OH)D (OR: 0.943, 95%CI: 0.858-1.037). Further analysis indicated that the main contributor to the decline in 25(OH)D levels is linked to PM2.5-10 exposure (OR: 0.840, 95%CI: 0.751-0.940) and PM2.5 absorbance (OR: 0.875, 95%CI: 0.824-0.929). No heterogeneity and horizontal pleiotropy existed.

CONCLUSIONS

The MR results suggest that PM (PM10, PM2.5-10 and PM2.5 absorbance) exposure lowers vitamin D (VD) levels, but PM2.5 was not found to have a significant effect on VD in humans.

Vitamin D Deficiency Is Frequent in Patients with Rapidly Destructive Osteoarthritis-Data from a Single-Center Analysis

BACKGROUND

Rapidly destructive osteoarthritis (RDO) of the hip joint is characterised by the rapid destruction of the femoral head with or without acetabular involvement. There has been increasing interest in this disease over the past years; however, the entity is still poorly understood, and its pathophysiology remains unknown. Yet, there is ample evidence today that increased bone metabolism might play a role in the onset and progression of the disease. Vitamin D is of utmost importance to maintain a balanced bone metabolism. However, whether vitamin D deficiency is involved in disease development remains to be elucidated. Further, the vitamin D status of patients with RDO has not yet been analysed. For this reason, the objective of this study was to assess the vitamin D status of patients with RDO. Moreover, the aim was to clarify whether there is a difference in the vitamin D status of patients with RDO compared with patients with primary osteoarthritis (OA).

METHODS

In this single-centre analysis, the 25(OH)D, PTH, and calcium levels of 29 patients who presented with RDO between 2020 and 2022 were assessed.

RESULTS

Altogether, 97% of patients (28/29) were vitamin D deficient, a further 3% (1/29) were vitamin D insufficient, and not a single patient presented with a sufficient vitamin D status. Notably, the vitamin D levels of RDO patients (mean = 11.04 ng/mL) were significantly lower than the vitamin D levels of patients with OA (mean = 22.16 ng/mL, p = 0.001).

CONCLUSION

In conclusion, we found a widespread and high rate of vitamin D deficiency in patients with RDO. Hence, we believe that 25(OH)D status should routinely be analysed in these patients.

Theoretical Studies on the Quantitative Structure-Toxicity Relationship of Polychlorinated Biphenyl Congeners Reveal High Affinity Binding to Multiple Human Nuclear Receptors

Polychlorinated biphenyls (PCBs) are organic chemicals consisting of a biphenyl structure substituted with one to ten chlorine atoms, with 209 congeners depending on the number and position of the chlorine atoms. PCBs are widely known to be endocrine-disrupting chemicals (EDCs) and have been found to be involved in several diseases/disorders. This study takes various molecular descriptors of these PCBs (e.g., molecular weight) and toxicity endpoints as molecular activities, investigating the possibility of correlations via the quantitative structure-toxicity relationship (QSTR). This study then focuses on molecular docking and dynamics to investigate the docking behavior of the strongest-binding PCBs to nuclear receptors and compares these to the docking behavior of their natural ligands. Nuclear receptors are a family of transcription factors activated by steroid hormones, and they have been investigated to consider the impact of PCBs on humans in this context. It has been observed that the docking affinity of PCBs is comparable to that of the natural ligands, but they are inferior in terms of stability and interacting forces, as shown by the RMSD and total energy values. However, it is noted that most nuclear receptors respond to PCBs similarly to how they respond to their natural ligands-as shown in the RMSF plots-the most similar of which are seen in the ER, THR-β, and RAR-α. However, this study is performed purely in silico and will need experimental verification for validation.

Relationship between serum vitamin D levels and the prevalence of knee osteoarthritis: A retrospective study on 3424 subjects

BACKGROUND

The extent of the association between vitamin D deficiency and knee osteoarthritis remains inadequately understood.

OBJECTIVE

This study aimed to elucidate the relationship between vitamin D levels and knee osteoarthritis through a cross-sectional analysis.

METHODS

This retrospective study involved an analysis of knee radiographs and serum 25-hydroxyvitamin D3 (25-(OH) vitamin D3) levels in a cohort of 3424 individuals (2901 women and 523 men). Knee osteoarthritis severity was evaluated using the Kellgren-Lawrence radiological scoring system.

RESULTS

Of the participants, 49.2% (n= 1,683) were diagnosed with knee osteoarthritis. Among these patients, the levels of adjusted 25-(OH) vitamin D3 were significantly lower (p< 0.001). Regression analysis revealed a significant association between vitamin D deficiency and knee osteoarthritis, with an adjusted odds ratio (OR) of 1.7 (95% CI: 1.5-2.0; p< 0.001). Notably, a stronger association was observed between vitamin D deficiency and knee osteoarthritis in women under 65 compared to those aged 65 and above.

CONCLUSIONS

The findings of this study indicate a higher prevalence of vitamin D deficiency in patients with knee osteoarthritis. Maintaining adequate serum 25-(OH) vitamin D3 levels may prevent knee osteoarthritis, especially in women below 65.

The Potential Role of Vitamin D Supplementation in Cognitive Impairment Prevention

BACKGROUND

Vitamin D is implicated in many processes in the central nervous system (CNS), such as neurogenesis, neurotransmitter synthesis, synaptogenesis and protection against oxidative stress, thereby exerting a neuroprotective effect.

OBJECTIVE

In the present review, we aimed to evaluate the potential benefit(s) of vitamin D supplementation for CNS aging in different clinical contexts.

METHODS

We performed a literature search, looking for clinical trials and randomized clinical trials evaluating the effect of vitamin D supplementation on different endpoints related to cognitive outcomes.

RESULTS

Firstly, we identified 16 papers dealing with the impact of vitamin D supplementation on cognitive function in healthy subjects; the current literature suggests a real role for vitamin D supplementation in the prevention of cognitive decay in this clinical setting. Conversely, two papers suggest that vitamin D supplementation may be beneficial in patients with mild cognitive impairment (MCI). Finally, current data on vitamin D in Alzheimer's disease are contradictory.

CONCLUSION

Vitamin D supplementation may improve the cognitive outcomes of patients with MCI, whereas there is no evidence that it may prevent dementia or modulate the course of Alzheimer's disease.

Basal Metabolic Rate Versus Dietary Vitamin D and Calcium Intakes and the Association With Body Composition and Bone Health After Chronic Spinal Cord Injury

We examined the association among basal metabolic rate (BMR) as well as dietary intakes of vitamin D (Vit D) and calcium on body composition and bone mineral density (BMD) after spinal cord injury (SCI). Cross-sectional design. Veterans Affairs Medical Center, Richmond, VA. About 33 individuals with chronic SCI who recorded their food consumption 3 days per week for 2 weeks. BMR was measured after 10 to 12 h of overnight fast. Average daily vit D and calcium intakes, and total caloric intake were recorded and analyzed using the Nutrition Data System for Research (NDSR) software. Fasting blood analysis for 25-hydroxyvitamin D (25[OH]D) status and Triiodothyronine (T3) status was performed (n = 10). Total and regional BMD, % fat mass (FM), and % lean mass (LM) were measured by dual X-ray absorptiometry scans. Participants consumed less than the Institute of Medicine (IOM) recommended daily allowances (RDA) for vit D (600-800 IU) and calcium (1000-1200 mg) for adults. BMR was positively related to total-lean mass (r = .62, P = .0001; n = 32) and leg-lean mass (r = .51, P = .003; n = 32). Adjusted BMR was negatively related to BMD of the left (r = -.38, P = .047; n = 28) and the right (r = -.41, P = .032; n = 28) proximal tibia. Vit D intake was negatively related to percentage total-FM (r = -.33, P = .07; n = 29) and legs-%FM (r = -.37, P = .047; n = 29). Multivariate regression models indicated that adjusted BMR explained the variance in leg fat mass (34%; P = .002) and percentage fat mass (44%; P < .0001). Persons with SCI are likely to consume less than the RDAs for vit D and calcium. BMR may explain the changes in body composition and bone metabolism. Dietary vit D should be considered as a prophylactic intervention in maintenance of bone health after SCI.

Vitamin D Supplementation at a Dose of 10 µg/Day in Institutionalized Children with Severe Motor and Intellectual Disabilities

Vitamin D (VD) deficiency can lead to health-related consequences. This study determined the effects of VD administration in VD-deficient children with severe motor and intellectual disabilities (SMID). Twenty-eight subjects were included. Among them, 25 subjects with parental consent for VD administration were given 10 µg/day (400 IU/day) of VD in April 2021. Serum 25-hydroxyvitamin D [25(OH)D] levels were measured at least 30 days after the start of VD administration. The total VD intake, serum 25(OH)D levels, and ultraviolet (UV) exposure before the blood tests were investigated. The results showed that the median serum 25(OH)D levels were 8.7 ng/mL (4.3-17.2) and 24.0 ng/mL (7.8-39 ng/mL) from March to May in 2020 and 2021, respectively. Among the 25 subjects, 22 with UV exposure had >20 ng/mL serum 25(OH)D level, and 2 without UV exposure had <20 ng/mL serum 25(OH)D level. Three subjects who did not receive VD supplementation had <20 ng/mL serum 25(OH)D level. Taken together, VD supplementation (10 µg/day) is effective in children with SMID in institutional care. Moreover, it may be sufficient for children with UV exposure, but not for those without.

Effects of Isoflavonoid and Vitamin D Synergism on Bone Mineral Density-A Systematic and Critical Review

Phytoestrogens are non-steroidal plant compounds, which bind to α and β estrogen receptors, thereby causing specific effects. The best-known group of phytoestrogens are flavonoids, including isoflavonoids-genistein and daidzein. They play a role in the metabolism of bone tissue, improving its density and preventing bone loss, which contributes to reducing the risk of fractures. Vitamin D is found in the form of cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) and is traditionally recognized as a regulator of bone metabolism. The aim of this review was to evaluate the synergistic effect of isoflavonoids and vitamin D on bone mineral density (BMD). The MEDLINE (PubMed), Scopus and Cochrane databases were searched independently by two authors. The search strategy included controlled vocabulary and keywords. Reference publications did not provide consistent data regarding the synergistic effect of isoflavonoids on BMD. Some studies demonstrated a positive synergistic effect of these compounds, whereas in others, the authors did not observe any significant differences. Therefore, further research on the synergism of isoflavonoids and vitamin D may contribute to a significant progress in the prevention and treatment of osteoporosis.

Examining the Role of Vitamin D in Caries Susceptibility in Children's Deciduous Teeth: A Systematic Review

The global prevalence of dental caries in deciduous teeth remains a significant health concern, affecting almost 70% of children by the age of six in specific regions. This systematic review aspired to methodically investigate the association between vitamin D levels and susceptibility to caries in children's deciduous teeth. A detailed search, guided by the PRISMA and PROSPERO guidelines, was conducted across three prominent electronic databases: PubMed, Web of Science, and Scopus, culminating in August 2023. The search integrated various keywords related to vitamin D and dental caries in primary dentition, yielding an initial pool of 1678 articles. After meticulous scrutiny, seven studies with a total of 7655 participants were deemed suitable for inclusion. The studies represented diverse geographical regions, showcasing varied vitamin D levels and sun exposure. Patient habits like brushing frequency, dental visits, and vitamin consumption also varied across studies. The analysis pinpointed vitamin D deficiency as a potential risk factor in some of the studies, with Odds Ratios (OR) ranging from 0.68 to 2.15. Statistically significant associations between vitamin D deficiency and caries susceptibility were documented in three studies (ORs of 2.15, 1.98, and 1.70). This comprehensive review elucidates the complex relationship between vitamin D levels and dental caries in children's deciduous teeth. While some studies spotlight vitamin D's pivotal role in dental health, inconsistencies across studies and regional differences necessitate more in-depth, globally representative investigations. Ensuring optimal vitamin D levels may play an integral role in dental health strategies. However, it is important to highlight that the roles of these studied factors might differ in deciduous teeth compared to permanent teeth.

Modulation of the vitamin D/vitamin D receptor system in osteoporosis pathogenesis: insights and therapeutic approaches

Osteoporosis is a prevalent bone disorder characterized by low bone mineral density (BMD) and deteriorated bone microarchitecture, leading to an increased risk of fractures. Vitamin D (VD), an essential nutrient for skeletal health, plays a vital role in maintaining bone homeostasis. The biological effects of VD are primarily mediated through the vitamin D receptor (VDR), a nuclear receptor that regulates the transcription of target genes involved in calcium and phosphate metabolism, bone mineralization, and bone remodeling. In this review article, we conduct a thorough literature search of the PubMed and EMBASE databases, spanning from January 2000 to September 2023. Utilizing the keywords "vitamin D," "vitamin D receptor," "osteoporosis," and "therapy," we aim to provide an exhaustive overview of the role of the VD/VDR system in osteoporosis pathogenesis, highlighting the most recent findings in this field. We explore the molecular mechanisms underlying VDR's effects on bone cells, including osteoblasts and osteoclasts, and discuss the impact of VDR polymorphisms on BMD and fracture risk. Additionally, we examine the interplay between VDR and other factors, such as hormonal regulation, genetic variants, and epigenetic modifications, that contribute to osteoporosis susceptibility. The therapeutic implications of targeting the VDR pathway for osteoporosis management are also discussed. By bringing together these diverse aspects, this review enhances our understanding of the VD/VDR system's critical role in the pathogenesis of osteoporosis and highlights its significance as a potential therapeutic target.

Association between vitamin D and knee osteoarthritis in Indian population: A systematic review and meta-analysis

Background

Vitamin D deficiency (VDD) has been implicated in knee osteoarthritis (KOA) development and progression. Prevalence of hypovitaminosis D and osteoporosis in KOA is widely reported in Indian population. However, there is no attempt to critically evaluate the outcome of these studies. We aimed a systematic review of these studies.

Methods

Pubmed, Google Scholar and Web of Science last updated March 2023, were searched. We reviewed eligible studies on the association between KOA and vitamin D levels in Indian and Asian population for comparison. The mean difference (MD) of vitamin D levels and odds ratio (OR) of vitamin D status were calculated. Data were interpreted by RevMan 5.4 software. The risk of bias was assessed using the Cochrane Risk of Bias tool.

Results

A total of 15 studies that involved 1503 KOA cases and 1609 controls were included. There was significantly reduced level of vitamin D in KOA (MD -8.68 ng/mL, 95%CI -12.21 to -5.15; P = <0.00001, I2 = 82 %) in Indian population. Similarly, in other Asian population significantly reduced vitamin D levels in KOA (MD 18.36 ng/mL, 95%CI -34.72 to -2.00; P = <0.00001, I2 = 100 %) was observed in KOA. VDD was found to be positively correlated with an increased risk of KOA.

Conclusion

Early diagnosis and management of VDD may provide the opportunity to delay the ongoing degenerative process of KOA and this study indicates the importance of screening VDD even in sunlight rich regions.

Bone Homeostasis and Physiology in Normal and Orthopaedic Disease Conditions

Some of the most common human systemic diseases-both benign and malignant-affect bone regulation, formation, and homeostasis (the cellular balance regulated by osteocytes, osteoblasts, and osteoclasts). This review discusses our current understanding of the molecular components and mechanisms that are responsible for homeostasis and interactions resulting in dysregulation (dysfunction due to the loss of the dynamic equilibrium of bone homeostasis). Knowledge of key pathways in bone biology can improve surgeon understanding, clinical recognition, and treatment of bone homeostasis-related diseases.

Phytosterols Protect against Osteoporosis by Regulating Gut Microbiota

Osteoporosis is increasingly prevalent worldwide, representing a major health burden. However, there is a lack of nutritional strategies for osteoporotic therapy. Phytosterols, as natural bioactive compounds, have the potential to alleviate osteoporosis. In this study, a glucocorticoid-induced osteoporosis mouse model and treatment with low and high concentrations of phytosterols for 4 weeks were established. The results demonstrated that compared to the control group, low-concentration phytosterols (LP) (0.3 mg/mL) increased bone mass, improved trabecular microstructure, reduced serum levels of cross-linked C-telopeptide of type I collagen (CTX-1), and elevated serum levels of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3). Conversely, high-concentration phytosterols (0.5 mg/mL) showed no effect. Additionally, we validated the effect of LP in ameliorating osteoporosis using an ovariectomized (OVX)-induced osteoporosis mouse model. Mechanistically, phytosterols altered the microbial composition to counteract glucocorticoid-induced gut microbiota disorder and improve the length and morphology of the small intestine. Particularly, based on selection strategy and correlation analysis, phytosterols increased the relative abundance of Ruminococcus and decreased the relative abundance of Bilophila, which were significantly associated with glucocorticoid-induced osteoporosis indications. Overall, these findings suggest that phytosterols regulate gut microbiota to increase bone mass, thereby exerting an antiosteoporotic effect.

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.

Effect of vitamin D deficiency on surgical outcomes of degenerative cervical myelopathy

Background

Due to its association with bone metabolic status and muscle strength/mass, vitamin D deficiency has the potential to affect neurological symptom recovery after surgery for degenerative cervical myelopathy (DCM). However, few studies have investigated the effects of vitamin D deficiency (serum 25(OH)D <20 ng/mL) on surgical outcomes in DCM patients. Herein, we investigated the prevalence of vitamin D deficiency in patients with DCM, and determined whether vitamin D deficiency affects surgical outcomes for DCM.

Methods

In this retrospective observational study we assessed the recovery rate 1 year after surgery in 91 patients diagnosed with DCM who underwent surgery. First, we analyzed the correlation between vitamin D levels and various background factors. Then, patients were divided into 2 groups according to vitamin D sufficiency, and univariate analysis was performed on vitamin D and surgical outcomes. Finally, Spearman correlation analyses were performed to identify factors correlated with recovery rate after surgery for DCM.

Results

The average Japanese Orthopedic Association score for the assessment of cervical myelopathy (C-JOA score) improved postoperatively. Age was positively correlated with vitamin D levels, and parathyroid hormone levels were negatively correlated with vitamin D levels. Among the 91 patients, 79.1% of patients were diagnosed with vitamin D deficiency. No significant differences in recovery rate were found between the vitamin D-deficient and vitamin D-sufficient groups. Finally, the Spearman correlation analysis showed a positive correlation between the preoperative C-JOA motor dysfunction score in the lower extremities and the recovery rate, while age demonstrated a negative correlation with recovery rate.

Conclusions

No association was found between vitamin D deficiency and clinical outcomes after surgery for DCM. The results of this study do not support the need to normalize vitamin D levels for achieving neurological improvements in patients with DCM.

No Significant Association between 25-OH Vitamin D Status and SARS-CoV-2 Antibody Response after COVID-19 Vaccination in Nursing Home Residents and Staff

Vitamin D is an essential nutrient for various physiological functions, including immunity. While it has been suggested that higher vitamin D levels/supplementation are associated with a better immune response to COVID-19 vaccination, conflicting data exist. Therefore, we aimed to investigate the association between vitamin D (25-hydroxyvitamin D) deficiency/supplementation, and SARS-CoV-2 antibody responses post-vaccination in nursing home residents (NHRs) and staff (NHS). Blood samples were collected from 115 NHRs and 254 NHS at baseline and 14 days after primary course BNT162b2 vaccination. Baseline samples were assessed for serum 25-hydroxyvitamin D levels, while follow-up samples were analyzed for spike protein S1 receptor-binding domain (S1RBD) IgG antibody concentrations and 50% pseudoneutralization titers. Vitamin D supplementation status was obtained from NHRs medical records. We compared immune responses between (severe) vitamin D-deficient and -sufficient NHRs/NHS and between supplemented and non-supplemented NHRs, stratified for history of SARS-CoV-2 infection and participant type. No significant differences in either binding or neutralizing COVID-19 vaccine antibody response were found between groups. The prevalence of vitamin D deficiency (<20 ng/mL) was 45% (95% CI: 36-54%) among NHRs and 60% (95% CI: 54-66%) among NHS. Although we showed that vitamin D status may not be related to a better COVID-19 vaccine antibody response, addressing the high prevalence of vitamin D deficiency in the nursing home population remains important.

Knowledge, attitudes, and practices associated with vitamin D supplementation: A cross-sectional online community survey of adults in the UK

OBJECTIVE

Assess knowledge, attitudes, and practices (KAPs) of a diverse population. Identify barriers and facilitators that inform routine vitamin D supplementation and self-care in the community setting.

DESIGN

Cross-sectional online voluntary survey. Electronic survey link published on college Qualtrics platform and advertised widely. Study information provided with Participant Information Sheet.

SETTING AND PARTICIPANTS

556 community dwelling adults across the UK.

METHODS

The overarching study included two phases, incorporating quantitative and qualitative methodologies. This paper reports findings from the first phase of the FABCOM-D (Facilitators and Barriers to Community (Healthy) Vitamin D status) study. Online survey questions were iteratively developed after background literature searches and piloted to ensure clarity and ease of understanding. Survey responses summarised using frequencies and percentages, and univariable and multivariable logistic regression models explored for any association. A p-value less than 0.05 was considered statistically significant. The Checklist for Reporting Results of Internet E-Surveys guided reporting. Statistical analysis performed using IBM SPSS software.

MAIN OUTCOME MEASURES

Awareness of vitamin D information sources, health benefits and testing. Attitudes to supplementation, sun exposure and fortification.

RESULTS

Three quarters of the community had some awareness of vitamin D and around half were taking supplements. The two most trusted sources of information included health professionals and the NHS website. Participants were willing to pay for supplements, supporting a self-care agenda. With increasing age, there was significant reduced intake of vitamin D supplements. This aspect needs to be explored further as this could be a concern in deficiency status in the elderly. There was acceptance of food fortification but uncertainty on how to balance food intake with supplementation.

CONCLUSION

We were successful in eliciting views on KAPs around vitamin D from a community population including a large proportion of Black and Minority Ethnic individuals. The community wanted information and guidance to help manage individual vitamin D status, especially for high-risk groups, and on balancing supplementation, food fortification and sun exposure.

Changes in bone biomarkers in response to different dosing regimens of cholecalciferol supplementation in children with chronic kidney disease

BACKGROUND

The effect of different dosing regimens of cholecalciferol supplementation on bone biomarkers has not been studied in children with chronic kidney disease (CKD).

METHODS

This is a post hoc analysis of a multi-center randomized controlled trial which included children with CKD stages 2-4 with vitamin D deficiency (25-hydroxy vitamin D (25OHD) < 30 ng/ml) randomized 1:1:1 to receive an equivalent dose of oral cholecalciferol as daily, weekly or monthly treatment. Markers of bone formation (bone alkaline phosphatase (BAP), procollagen I N terminal peptide (PINP)), bone resorption (tartarate-resistant acid phosphatase 5b (TRAP), C terminal telopeptide (CTX)), and osteocyte markers (intact fibroblast growth factor 23 (iFGF23), sclerostin) and soluble klotho were measured at baseline and after 3 months of intensive replacement therapy. The change in biomarkers and ratio of markers of bone formation to resorption were compared between treatment arms. BAP and TRAP were expressed as age- and sex-specific z-scores.

RESULTS

25OHD levels increased with cholecalciferol supplementation, with 85% achieving normal levels. There was a significant increase in the BAP/TRAP ratio (p = 0.04), iFGF23 (p = 0.004), and klotho (p = 0.002) with cholecalciferol therapy, but this was comparable across all three therapy arms. The BAPz was significantly higher in the weekly arm (p = 0.01). The change in 25OHD (Δ25OHD) inversely correlated with ΔPTH (r =  - 0.4, p < 0.001).

CONCLUSIONS

Although cholecalciferol supplementation was associated with a significant increase in bone formation, the three dosing regimens of cholecalciferol supplementation have a comparable effect on the bone biomarker profile, suggesting that they can be used interchangeably to suit the patient's needs and optimize adherence to therapy. A higher resolution version of the Graphical abstract is available as Supplementary information.

Role of Vitamin D in Head and Neck Cancer-Immune Function, Anti-Tumour Effect, and Its Impact on Patient Prognosis

Head and neck squamous cell carcinoma (HNSCC) describes a heterogeneous group of human neoplasms of the head and neck with high rates of morbidity and mortality, constituting about 3% of all cancers and ~1.5% of all cancer deaths. HNSCC constituted the seventh most prevalent human malignancy and the most common human cancer in the world in 2020, according to multi-population observations conducted by the GLOBOCAN group. Since approximately 60-70% of patients present with stage III/IV neoplastic disease, HNSCC is still one of the leading causes of death in cancer patients worldwide, with an overall survival rate that is too low, not exceeding 40-60% of these patients. Despite the application of newer surgical techniques and the implementation of modern combined oncological treatment, the disease often follows a fatal course due to frequent nodal metastases and local neoplastic recurrences. The role of micronutrients in the initiation, development, and progression of HNSCC has been the subject of considerable research. Of particular interest has been vitamin D, the pleiotropic biologically active fat-soluble family of secosteroids (vitamin-D-like steroids), which constitutes a key regulator of bone, calcium, and phosphate homeostasis, as well as carcinogenesis and the further development of various neoplasms. Considerable evidence suggests that vitamin D plays a key role in cellular proliferation, angiogenesis, immunity, and cellular metabolism. A number of basic science, clinical, and epidemiological studies indicate that vitamin D has multidirectional biological effects and influences anti-cancer intracellular mechanisms and cancer risk, and that vitamin D dietary supplements have various prophylactic benefits. In the 20th century, it was reported that vitamin D may play various roles in the protection and regulation of normal cellular phenotypes and in cancer prevention and adjunctive therapy in various human neoplasms, including HNSCC, by regulating a number of intracellular mechanisms, including control of tumour cell expansion and differentiation, apoptosis, intercellular interactions, angio- and lymphogenesis, immune function, and tumour invasion. These regulatory properties mainly occur indirectly via epigenetic and transcriptional changes regulating the function of transcription factors, chromatin modifiers, non-coding RNA (ncRNAs), and microRNAs (miRs) through protein-protein interactions and signalling pathways. In this way, calcitriol enhances intercellular communication in cancer biology, restores the connection with the extracellular matrix, and promotes the epithelial phenotype; it thus counteracts the tumour-associated detachment from the extracellular matrix and inhibits the formation of metastases. Furthermore, the confirmation that the vitamin D receptor (VDR) is present in many human tissues confirmed the physiopathological significance of vitamin D in various human tumours. Recent studies indicate quantitative associations between exposure to vitamin D and the incidence of HNC, i.e., cancer risk assessment included circulating calcidiol plasma/serum concentrations, vitamin D intake, the presence of the VDR gene polymorphism, and genes involved in the vitamin D metabolism pathway. Moreover, the chemopreventive efficacy of vitamin D in precancerous lesions of the head and neck and their role as predictors of mortality, survival, and recurrence of head and neck cancer are also widely discussed. As such, it may be considered a promising potential anti-cancer agent for developing innovative methods of targeted therapy. The proposed review discusses in detail the mechanisms regulating the relationship between vitamin D and HNSCC. It also provides an overview of the current literature, including key opinion-forming systematic reviews as well as epidemiological, prospective, longitudinal, cross-sectional, and interventional studies based on in vitro and animal models of HNSCC, all of which are accessible via the PubMed/Medline/EMBASE/Cochrane Library databases. This article presents the data in line with increasing clinical credibility.

Vitamin D and Bone fragility in Individuals with Osteogenesis Imperfecta: A Scoping Review

Vitamin D affects several body functions, and thus general health, due to its pleiotropic activity. It plays a key role in bone metabolism, and its deficiency impacts bone development, leading to bone fragility. In osteogenesis imperfecta (OI), a group of hereditary connective tissue disorders characterized by bone fragility, additional factors, such as vitamin D deficiency, can affect the expression of the phenotype and aggravate the disorder. The aim of this scoping review was to assess the incidence of vitamin D deficit in OI patients and the association between vitamin D status and supplementation in individuals affected by OI. We searched the PubMed Central and Embase databases and included studies published between January/2000 and October/2022 evaluating vitamin D measurement and status (normal, insufficiency, deficiency) and supplementation for OI. A total of 263 articles were identified, of which 45 were screened by title and abstract, and 10 were included after a full-text review. The review showed that low levels of vitamin D was a frequent finding in OI patients. Vitamin D supplementation was mainly indicated along with drug therapy and calcium intake. Even if widely used in clinical practice, vitamin D supplementation for OI individuals still needs a better characterization and harmonized frame for its use in the clinical setting, as well as further studies focusing on its effect on bone fragility.

Low Magnesium Concentration Enforces Bone Calcium Deposition Irrespective of 1,25-Dihydroxyvitamin D3 Concentration

Efficient coordination between Mg²⁺ and vitamin D maintains adequate Ca²⁺ levels during lactation. This study explored the possible interaction between Mg²⁺ (0.3, 0.8, and 3 mM) and 1,25-dihydroxyvitamin D₃ (1,25D; 0.05 and 5 nM) during osteogenesis using bovine mesenchymal stem cells. After 21 days, differentiated osteocytes were subjected to OsteoImage analysis, alkaline phosphatase (ALP) activity measurements, and immunocytochemistry of NT5E, ENG (endoglin), SP7 (osterix), SPP1 (osteopontin), and the BGLAP gene product osteocalcin. The mRNA expression of NT5E, THY1, ENG, SP7, BGLAP, CYP24A1, VDR, SLC41A1, SLC41A2, SLC41A3, TRPM6, TRPM7, and NIPA1 was also assessed. Reducing the Mg²⁺ concentration in the medium increased the accumulation of mineral hydroxyapatite and ALP activity. There was no change in the immunocytochemical localization of stem cell markers. Expression of CYP24A1 was higher in all groups receiving 5 nM 1,25D. There were tendencies for higher mRNA abundance of THY1, BGLAP, and NIPA1 in cells receiving 0.3 mM Mg²⁺ and 5 nM 1,25D. In conclusion, low levels of Mg²⁺ greatly enhanced the deposition of bone hydroxyapatite matrix. The effect of Mg²⁺ was not modulated by 1,25D, although the expression of certain genes (including BGLAP) tended to be increased by the combination of low Mg²⁺ and high 1,25D concentrations.

Potential benefits of vitamin D supplementation on pregnancy

BACKGROUND

The level of vitamin D in pregnant women and the effect of vitamin D supplementation are lack in Taiwan.

OBJECTIVE

To investigate the vitamin D serum level and the effect of its supplementation on pregnancy.

METHODS

We included 1048 pregnant women who underwent prenatal exam with known serum 25-hydroxyvitamin D3 [25(OH)D3] levels and delivery at the Mackay Memorial Hospital, Taipei, Taiwan during 2015-2018. A daily dose 2000 IU of vitamin D was given, starting at 12-16 weeks of pregnancy, to reach the level of 20 ng/mL, and then a maintenance dose of 800 IU/day was given. The other 3654 women without vitamin D supplementation delivered in 2018 served as control group. Pregnancy outcomes were recorded for analysis.

RESULTS

Over 80% of the 1048 pregnant women were vitamin D deficiency. There was an inverse correlation between serum vitamin D levels and maternal body mass index (p = 0.0366). We compared 375 women with serum vitamin D levels increased above 30 ng/mL after supplementation with control group. The rates of preterm birth, low birth weight, and postpartum hemorrhage between these 2 groups were 6.67% vs. 11.19% (p = 0.007), 6.40% vs. 10.0% (p = 0.025), and 1.33% vs. 3.20% (p = 0.04), respectively.

CONCLUSIONS

Vitamin D deficiency is very prevalent in pregnant women, especially those with high BMI, in Taiwan. It can be corrected by adequate vitamin D supplementation, which may decrease the risk of pregnancy complications and bring benefits to the fetus.

A Simultaneous Extraction/Derivatization Strategy for Quantitation of Vitamin D in Dried Blood Spots Using LC–MS/MS: Application to Biomarker Study in Subjects Tested for SARS-CoV-2

Vitamin D plays a critical role in bone development and maintenance, and in other physiological functions. The quantitation of endogenous levels of individual vitamin D and its metabolites is crucial for assessing several disease state conditions. With cases of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) leading to the coronavirus disease 2019 (COVID-19) pandemic, there are several studies that have associated lower levels of serum vitamin D with severity of infection in COVID-19 patients. In this context, we have developed and validated a robust LC–MS/MS method for simultaneous quantitation of vitamin D and its metabolites in human dried blood spot (DBS) obtained from participants tested for COVID-19. The chromatographic separation for vitamin D and metabolites was performed using an ACE Excel C18 PFP column protected with a C18 guard column (Phenomenex, Torrance, CA, USA). The mobile phase consisted of formic acid in water (0.1% v/v) as mobile phase A and formic acid in methanol (0.1% v/v) as mobile phase B, operated at a flow rate of 0.5 mL/min. Analysis was performed utilizing the LC–MS/MS technique. The method was sensitive with a limit of quantification of 0.78 ng/mL for all analytes, and had a large dynamic range (200 ng/mL) with a total run time of 11 min. The inter- and intraday accuracy and precision values met the acceptance criteria per the US Food and Drug Administration guidelines. Blood concentrations of 25(OH)D3, vitamin D3, 25(OH)D2, and vitamin D2 over a range of 2–195.6, 0.5–121.5, 0.6–54.9, and 0.5–23.9 ng/mL, respectively, were quantified in 909 DBS samples. In summary, our developed LC−MS/MS method may be used for quantification of vitamin D and its metabolites in DBS, and may be applied to investigations of the emerging role of these compounds in various physiological processes.

Influence of vitamin D metabolites on vitamin D status, immunity and gut health of piglets

Immediately post-weaning, piglets are prone to gastrointestinal infectious diseases. The active metabolite of vitamin D 1,25-dihydroxyvitamin D has direct impact on immune cell function and responses. Thus, a low vitamin D status may compromise the immune responses during infectious diseases. The aim of this study was to examine the effect of supplementation of different forms of vitamin D (25-OH-D₃ and vitamin D₃) to suckling piglets' vitamin D status at weaning. In addition, to determine whether the vitamin D status could affect the immune development in piglets and their robustness against E. coli challenge. Genetically E. coli F4 susceptible litters of piglets were divided into two treatment groups: group 1 (n = 16) provided milk formula supplemented with vitamin D₃ (CON), and group 2 (n = 16) provided milk formula supplemented with 25-OH-D₃ (TREAT). Piglets were offered the experimental milk formulas from day 3 after farrowing until weaning (at day 28 of age). A commercial weaner diet with high protein content were provided to induce weaning stress. Milk formulas, sow and weaner diets as well as plasma and milk samples obtained from sows (n = 8) were analysed for vitamin D metabolites. Vitamin D status in piglets was investigated by collection of plasma samples on day 3, 15, 28 and 35 of age. Eight piglets randomly selected from each dietary group (in total 16 pigs) were inoculated with E. coli F4 O149 on day 2 and 3 post-weaning. Blood samples collected on day 2 and 9 post-weaning (pre- and post E. coli inoculation, respectively) were analysed for haematological and immunological parameters including immunoglobulins, antibodies specific to E. coli O149 K88, cytokines and C-reactive protein. In addition, intestinal samples were obtained one week after E. coli inoculation to study the influence of infection and vitamin D status on immune responses at different sites of the intestine. This was accomplished by gene expression of various cytokines and tight junction proteins. In general, vitamin D status of the piglets were low. However, piglets provided TREAT during the suckling period had increased vitamin D status at weaning compared to piglets provided CON. Vitamin D was used during activation of the immune system as pigs inoculated with E. coli had lower plasma concentrations of 25-OH-D₃ than non-inoculated pigs possibly due to mobilising of vitamin D in the liver. Hence, increased vitamin D status at weaning might improve piglets' resistance to E. coli infection.

Vitamin D and Bone: A Story of Endocrine and Auto/Paracrine Action in Osteoblasts

Despite its rigid structure, the bone is a dynamic organ, and is highly regulated by endocrine factors. One of the major bone regulatory hormones is vitamin D. Its renal metabolite 1α,25-OH2D3 has both direct and indirect effects on the maintenance of bone structure in health and disease. In this review, we describe the underlying processes that are directed by bone-forming cells, the osteoblasts. During the bone formation process, osteoblasts undergo different stages which play a central role in the signaling pathways that are activated via the vitamin D receptor. Vitamin D is involved in directing the osteoblasts towards proliferation or apoptosis, regulates their differentiation to bone matrix producing cells, and controls the subsequent mineralization of the bone matrix. The stage of differentiation/mineralization in osteoblasts is important for the vitamin D effect on gene transcription and the cellular response, and many genes are uniquely regulated either before or during mineralization. Moreover, osteoblasts contain the complete machinery to metabolize active 1α,25-OH2D3 to ensure a direct local effect. The enzyme 1α-hydroxylase (CYP27B1) that synthesizes the active 1α,25-OH2D3 metabolite is functional in osteoblasts, as well as the enzyme 24-hydroxylase (CYP24A1) that degrades 1α,25-OH2D3. This shows that in the past 100 years of vitamin D research, 1α,25-OH2D3 has evolved from an endocrine regulator into an autocrine/paracrine regulator of osteoblasts and bone formation.

Integrated Transcriptome and Microbiota Reveal the Regulatory Effect of 25-Hydroxyvitamin D Supplementation in Antler Growth of Sika Deer

The level of plasma 25-hydroxyvitamin D (25(OH)D) is associated with the growth of the antler, a fast-growing bone organ of Cervidae. However, the benefits of 25(OH)D supplementation on antler growth and the underlying mechanisms remain unclear. Here, the antler growth profile and transcriptome, plasma parameters, rumen bacteria, and metabolites (volatile fatty acids and amino acids) were determined in sika deer in a 25(OH)D supplementation group (25(OH)D, n = 8) and a control group (Ctrl, n = 8). 25(OH)D supplementation significantly increased the antler weight and growth rate. The levels of IGF-1,25(OH)D and 1,25-dihydroxyvitamin D were significantly higher in the 25(OH)D group than in the Ctrl group, while the levels of LDL-C were lower. The levels of valerate and branched-chain amino acids in the rumen fluid were significantly different between the 25(OH)D and Ctrl groups. The bacterial diversity indices were not significantly different between the two groups. However, the relative abundances of the butyrate-producing bacteria (families Lachnospiraceae and Succinivibrionaceae) and the pyruvate metabolism pathway were higher in the 25(OH)D group. The transcriptomic profile of the antler was significantly different between the 25(OH)D and Ctrl groups, with 356 up- and 668 down-regulated differentially expressed genes (DEGs) in the 25(OH)D group. The up-regulated DEGs were enriched in the proteinaceous extracellular matrix and collagen, while the down-regulated DEGs were enriched in the immune system and lipid metabolism pathways. Overall, these results provide novel insights into the effects of 25(OH)D supplementation on the host metabolism, rumen microbiota, and antler transcriptome of sika deer.

Evaluation of vitamin D supplementation intake among children; cross-sectional observational study

BACKGROUND

The purpose of this study was to review the vitamin D supplementation intake status among children in the general public, determine the vitamin D supplements practices, and the barriers that parents and children face with supplementation.   Methods: A cross-sectional observational questionnaire-based survey study design was used. A convenience sampling technique was used to collect the data. An online Rao soft sample size calculator was applied to determine the sample size of 319. The response rate of participants was expected to be 63%, the margin of error was 5% and the level of confidence was 95%.   Results: A total of 248 parents (89.1% mothers (n =203)) and 15.7% fathers (n=39) with a mean ± SD age of 35.4 ± 7.04 years, completed the study (77.7% response rate). Parents reported that the supplements used the most by children were vitamin D supplements (21.85%) and multivitamins (21.8%) followed by calcium supplements (5.6%). However, 27.8% of children in this study did not take any supplements. Of all the parents, 65% (162) of them reported sending their child outside to play while 34.67% (86) of parents had reported no outdoor activity. Approximately 184 (74.2%) parents reported the child's diet to contain multiple natural sources of vitamin D. However, 69 (27.8%) parents reported giving none of the natural sources of vitamin D to their children through the diet. Parents with higher education about 62.9% (n=156) had a higher frequency of providing vitamin D supplements to their children. Children in high-income families (43.63%) were more likely to take vitamin D supplements than those in middle- or low-income families.     Conclusion: The study concluded that challenges like the educational and financial background of parents, family-income level, and health insurance status could help aid in addressing the overall burden of vitamin D deficiency among young children.

Evaluation of vitamin D supplementation intake among children; cross-sectional observational study

Background: The purpose of this study was to assess  the vitamin D supplementation intake status among children from different nationalities in the UAE,  to determine vitamin D intake practices through diet and lifestyle, and the barriers that parents in the UAE  face with providing vitamin D supplementation to their children.   Methods: A cross-sectional observational questionnaire-based survey study design was used.. The study was conducted in the U.A.E and the study participants were parents of children from ages 4-15 years. The questionnaire used in this study was both self-administered and interviewer-administered while inquiring the questions from the parents. A convenience sampling technique was used to collect the data. The response rate of participants was expected to be 63%, the margin of error was 5% and the level of confidence was 95%.   Results: A total of 248 participants (203 mothers, 39 fathers and 6 caregivers) completed the study. Participants reported that the supplements used the most by children were vitamin D supplements (21.85%), followed by multivitamins (21.8%) and calcium supplements (5.6%) and 27.8% of participants in this study reported  to  no  supplementation at all. The rate of vitamin D supplementation among children was higher in those families with higher income levels, parents/caregivers who were more educated, those families who attained health insurance. However, there was no statistical significance between these correlations. Conclusion: The study concluded that challenges like the educational and financial background of parents, family-income level, and health insurance status could help aid in addressing the overall burden of vitamin D deficiency among young children in the UAE. Pediatricians and health care professionals could use our study and use it as an aid to provide screening on lifestyle, sun light exposure, and dietary modifications and also educate parents why and how vitamin D is crucial for their children.

Effect of supplemental vitamin D3 on bone mineral density: a systematic review and meta-analysis

Context

There is still controversy over the effect of vitamin D3 supplementation on bone health.

Objective

The effects of vitamin D3 supplementation on bone mineral density (BMD) and markers of bone turnover, as well as the dose-response relationship between vitamin D3 and bone health in adults, were evaluated.

Data Sources

The PubMed, Scopus, Cochrane, Web of Science, and AGRIS databases were searched for articles published through April 30, 2022. Thirty-nine of the 6409 records identified met the inclusion criteria

Data Extraction

Data were extracted from articles by 2 authors, and data extraction was cross-checked independently. A random-effects model was used to estimate the pooled effect size and the associated 95%CI for the effect of vitamin D3 for each outcome. A one-stage random-effects dose-response model was used to estimate the dose-response relationship between vitamin D3 supplementation and BMD.

Data Analysis

Results of meta-analysis showed a beneficial effect of vitamin D3 at the lumbar spine (standardized mean difference [SMD] = 0.06; 95%CI, 0.01–0.12) and femoral neck (SMD = 0.25; 95%CI, 0.09–0.41). Dose-response analysis revealed a linear relationship between vitamin D3 supplementation doses and BMD at the femoral neck, lumbar spine, and total hip sites. No significant effect of vitamin D3 supplementation on whole-body or total hip BMD was observed (P &gt; 0.05). Vitamin D3 supplementation significantly decreased BMD at both proximal and distal forearm (SMD = −0.16; 95%CI, −0.26 to −0.06). The variables of ethnicity, age, baseline 25-hydroxyvitamin D (25[OH]D), menopause status, vitamin D3 dosing frequency, and bone health status (P interaction = 0.02) altered the effect of vitamin D3 supplementation on BMD. Additionally, a nonlinear relationship between vitamin D3 supplement doses and markers of bone turnover was found.

Conclusion

A protective effect of vitamin D3 supplementation on BMD of the lumbar spine, femoral neck, and total hip is implicated.

Systematic Review Registration

PROSPERO registration number CRD42017054132.

The effect of antiretroviral therapy initiation on vitamin D levels and four oral diseases among Kenyan children and adolescents living with HIV

OBJECTIVES

The impact of antiretroviral treatment (ART) on the occurrence of oral diseases among children and adolescents living with HIV (CALHIV) is poorly understood. The aim of this study was to determine the effect of ART timing on vitamin D levels and the prevalence of four oral diseases (dry mouth, dental caries, enamel hypoplasia, and non-herpes oral ulcer) among Kenyan CALHIV from two pediatric HIV cohorts.

METHODS

This nested cross-sectional study was conducted at the Kenyatta National Hospital, Nairobi, Kenya. CALHIV, 51 with early-ART initiated at <12 months of age and 27 with late-ART initiated between 18 months-12 years of age, were included. Demographics, HIV diagnosis, baseline CD4 and HIV RNA viral load data were extracted from the primary study databases. Community Oral Health Officers performed oral health examinations following standardized training.

RESULTS

Among 78 CALHIV in the study, median age at the time of the oral examination was 11.4 years old and median ART duration at the time of oral examination was 11 years (IQR: 10.1, 13.4). Mean serum vitamin D level was significantly higher among the early-ART group than the late-ART group (29.5 versus 22.4 ng/mL, p = 0.0002). Children who received early-ART had a 70% reduction in risk of inadequate vitamin D level (<20 ng/mL), compared to those who received late-ART (p = 0.02). Although both groups had similar prevalence of oral diseases overall (early-ART 82.4%; late-ART 85.2%; p = 0.2), there was a trend for higher prevalence of dry mouth (p = 0.1) and dental caries (p = 0.1) in the early versus late ART groups. The prevalence of the four oral diseases was not associated with vitamin D levels (p = 0.583).

CONCLUSIONS

After >10 years of ART, CALHIV with early-ART initiation had higher serum vitamin D levels compared to the late-ART group. The four oral diseases were not significantly associated with timing of ART initiation or serum vitamin D concentrations in this cohort. There was a trend for higher prevalence of dry mouth and dental caries in the early-ART group, probably as side-effects of ART.

Vitamin C epigenetically controls osteogenesis and bone mineralization

Vitamin C deficiency disrupts the integrity of connective tissues including bone. For decades this function has been primarily attributed to Vitamin C as a cofactor for collagen maturation. Here, we demonstrate that Vitamin C epigenetically orchestrates osteogenic differentiation and function by modulating chromatin accessibility and priming transcriptional activity. Vitamin C regulates histone demethylation (H3K9me3 and H3K27me3) and promotes TET-mediated 5hmC DNA hydroxymethylation at promoters, enhancers and super-enhancers near bone-specific genes. This epigenetic circuit licenses osteoblastogenesis by permitting the expression of all major pro-osteogenic genes. Osteogenic cell differentiation is strictly and continuously dependent on Vitamin C, whereas Vitamin C is dispensable for adipogenesis. Importantly, deletion of 5hmC-writers, Tet1 and Tet2, in Vitamin C-sufficient murine bone causes severe skeletal defects which mimic bone phenotypes of Vitamin C-insufficient Gulo knockout mice, a model of Vitamin C deficiency and scurvy. Thus, Vitamin C's epigenetic functions are central to osteoblastogenesis and bone formation and may be leveraged to prevent common bone-degenerating conditions.

The impact of vitamin D(3) on bone remodeling in different types of experimental pathology

Osteoporosis is a progressive systemic skeletal disease characterized by a decrease in bone density, impairment of its microarchitectonics, and an increased risk of fractures that occur under minimal or no mechanical stress. One of the main causes of osteoporosis is vitamin D deficiency, which leads to disruption of normal bone remodeling. The aim of our study was to analyze the features of the process of bone tissue remodeling by measuring the key biochemical markers of bone formation/resorption in primary and secondary osteoporosis, as well as to investigate the potential corrective effect of vitamin D3 supplementation. The work was conducted on rats with different osteoporosis models: alimentary, dysfunctional and secondary osteoporosis associated with diabetes mellitus. We used ELISA to measure 25(OH)D content in blood serum. Blood serum and bone tissue calcium, and alkaline phosphatase activity were determined with bioassay kits. The content of inorganic phosphate in blood serum and ash was assayed by the Dyce method. It was shown that all the studied pathological conditions were accompanied by vitamin D deficiency, which led to impaired absorption of calcium in the intestine and reabsorption of inorganic phosphates by the kidneys, reducing, as a result, their concentration in the blood serum. Hypocalcemia and hypophosphatemia contributed to the disruption of normal bone remodeling, excessive activation of alkaline phosphatase, and a decrease in the content of calcium and phosphate in bone tissue. Thus, sufficient vitamin D bioavailability was confirmed to be critical for effective bone remodeling in primary and secondary osteoporosis. Keywords: bone remodelin, osteoporosis, type 1 diabetes mellitus, vitamin D

Vitamin D: a potentially important secosteroid for coping with COVID-19

COVID-19 is a disease that has caused a high number of deaths in the world, and despite being controlled, it requires attention and the search for new quick and economical therapeutic strategies. In this sense, vitamin D stands out, an immunomodulator that has shown beneficial effects in decreasing the risk and severity of acute respiratory tract infections, including COVID-19. Therefore, this review presents a number of experimental, observational and clinical studies on the importance of vitamin D against viral infections with an emphasis on COVID-19, highlighting the relationship between vitamin D, Renin-Angiotensin System and cytokine storms with decreased inflammatory lesions in patients with COVID-19. In addition, aspects of pathophysiology, metabolism, risk factors, sources and recommendations of vitamin D are described. We conclude that vitamin D plays a protective role against inflammatory lesions and can decrease the risk of infections and the severity of COVID-19. Therefore, it is essential to maintain adequate levels of vitamin D to avoid complications related to its deficiency.

Adiposity Metabolic Consequences for Adolescent Bone Health

Infancy and adolescence are crucial periods for bone health, since they are characterized by intense physical growth and bone development. The unsatisfactory acquisition of bone mass in this phase has consequences in adult life and increases the risk of developing bone diseases at more advanced ages. Nutrient deficiencies, especially calcium and vitamin D, associated with a sedentary lifestyle; lack of sun exposure; and epigenetic aspects represent some of the main risk factors for poor bone quality. In addition, recent studies relate childhood obesity to impaired bone health; however, studies on the adiposity effects on bone health are scarce and inconclusive. Another gap concerns the implications of obesity on child sexual maturity, which can jeopardize their genetic potential bone mass and increase fracture risk. Therefore, we reviewed the analyzed factors related to bone health and their association with obesity and metabolic syndrome in adolescents. We concluded that obesity (specifically, accumulated visceral fat) harms bones in the infant-juvenile phase, thereby increasing osteopenia/osteoporosis in adults and the elderly. Thus, it becomes evident that forming and maintaining healthy eating habits is necessary during infancy and adolescence to reduce the risk of fractures caused by bone-metabolic diseases in adulthood and to promote healthy ageing.

Lag associations of gestational phthalate exposure with maternal serum vitamin D levels: Repeated measure analysis

Few studies have investigated the relationships between gestational phthalate exposure and maternal circulating vitamin D. In the Ma'anshan birth cohort, 3265 pregnant women were included. Each woman provided up to three urine and serum samples for measurement of phthalates and 25(OH)D and calcium, respectively. Linear mixed models were performed to analyse the association between phthalate metabolites and 25(OH)D and calcium. Stratified analyses of the relationship between phthalates and 25(OH)D by urine collection season were conducted. Finally, the post hoc lag effect of phthalate exposure on 25(OH)D was determined if longitudinal associations were significant. Some phthalate metabolites were associated with increased 25(OH)D but with decreased calcium. Furthermore, the relationship of phthalate exposure with 25(OH)D varied with urine collection season. Phthalate metabolites collected in summer and autumn were associated with an increase in 25(OH)D, while monobenzyl phthalate collected in winter and spring was inversely associated with 25(OH)D. Finally, high-molecular-weight phthalates had lag associations with 25(OH)D with a 1-trimester lag period. Low-molecular-weight phthalates exhibited lag associations with 25(OH)D with a 2-trimester lag period. In conclusion, the positive cross-sectional correlation between phthalate metabolites and 25(OH)D was partly affected by urine collection season. This study suggested that gestational phthalate exposure would have a lag association with maternal 25(OH)D levels.

Vitamin D, bone density, and nephrocalcinosis in preterm infants: a prospective study

BACKGROUND

Vitamin D (VitD) supplementation is recommended by the American Academy of Pediatrics (AAP) for preterm infants to improve bone density. Complications of VitD supplementation include hypercalciuria and nephrocalcinosis (NC). NC has been reported in 7-64% infants < 32 weeks gestational age (GA) or < 1500 g birth weight (BW). The relationships between VitD supplementation, serum 25-hydroxy VitD levels, bone density, hypercalciuria and development of NC in preterm infants are not well established.

METHODS

Prospective, observational cohort study of 56 infants with GA ≤ 32 weeks or BW ≤ 1800 g. Demographics, dietary intakes, serum 25-hydroxy VitD levels and weekly urinalyses were collected until 40 weeks corrected GA or discharge. Bone mineral density (BMD) and content (BMC) were assessed using dual-energy X-ray absorptiometry (DEXA) scan. NC was identified by kidney ultrasound.

RESULTS

56 infants received on average 447 IU/day of VitD with average serum 25-hydoxy VitD level 39.6 ng/mL. DEXA scan showed average BMD 0.13 g/cm² and BMC 35.8 g. 23/56 (41%) infants were diagnosed with NC. Infants with NC had lower GA (p < 0.01) and BW (p < 0.01) and increased presence of calcium oxalate crystals (78% vs. 36%) (p = 0.002). There were no differences in VitD intake, urine calcium/creatinine ratios or BMD and BMC in infants with versus without NC.

CONCLUSIONS

VitD supplementation per AAP guidelines resulted in acceptable serum 25-hydroxyVitD levels, but no improvement in BMD or BMC compared to previously reported values. However, infants receiving recommended amounts born at earlier GA and lower BW are at increased risk of NC. VitD supplementation and serum levels should be closely monitored in this high-risk population. A higher resolution version of the Graphical abstract is available as Supplementary information.

Metabolomic Profiling of Samples from Pediatric Asthma Patients Unveils Deficient Nutrients in African Americans

Plasma metabolomics represents a potentially powerful approach to understand the biochemical mechanisms of nutrition and metabolism in asthma. This study aims to acquire knowledge on plasma metabolites in asthma, which may provide avenues for nutrition therapy, as well as explanations for the observed effects in existing therapies. This study investigated 249 metabolites from 18 metabolite groups in a large cohort of African American population, including 602 pediatric patients with asthma and 593 controls, using a nuclear magnetic resonance (NMR) metabolomics platform. Decreased levels of citrate, ketone bodies, and two amino acids histidine (His) and glutamine (Gln), were observed in asthma cases compared to controls. Metabolites for lipid metabolism lost significance after controlling for comorbid obesity. For the first time, this study depicts a broad panorama of lipid metabolism and nutrition in asthma. Supplementation or augmentation of nutrients that are deficient may be beneficial for asthma care.

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Asthma is a major health issue in African Americans

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Metabolomics represents a powerful approach to understand the metabolism in asthma

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We observed decreased citrate, ketone bodies, and amino acids in the plasma

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Supplementation of nutrients that are deficient may be beneficial for asthma care

Interplay of Vitamin D and CYP3A4 Polymorphisms in Endocrine Disorders and Cancer

Vitamin D has received considerable optimistic attention as a potentially important factor in many pathological states over the past few decades. However, the proportion of the active form of vitamin D metabolites responsible for biological activity is highly questionable in disease states due to flexible alterations in the enzymes responsible for their metabolism. For instance, CYP3A4 plays a crucial role in the biotransformation of vitamin D and other drug substances. Food-drug and/or drug-drug interactions, the disease state, genetic polymorphism, age, sex, diet, and environmental factors all influence CYP3A4 activity. Genetic polymorphisms in CYP450-encoding genes have received considerable attention in the past few decades due to their extensive impact on the pharmacokinetic and dynamic properties of drugs and endogenous substances. In this review, we focused on CYP3A4 polymorphisms and their interplay with vitamin D metabolism and summarized the role of vitamin D in calcium homeostasis, bone diseases, diabetes, cancer, other diseases, and drug substances. We also reviewed clinical observations pertaining to CYP3A4 polymorphisms among the aforementioned disease conditions. In addition, we highlighted the future perspectives of studying the pharmacogenetics of CYP3A4, which may have potential clinical significance for developing novel diagnostic genetic markers that will ascertain disease risk and progression.

Vitamin D Deficiency and Outcomes After Ankle Fusion: A Short Report

BACKGROUND

Vitamin D deficiency has been postulated as a cause for impaired bone healing and remodeling. The purpose of this study was to assess the potential association between low vitamin D levels and reoperation for nonunion following ankle fusion surgery.

METHODS

All adult patients (aged ≥18 years) who underwent ankle fusion procedures at a tertiary referral center from January 2010 to January 2019 with available vitamin D levels within 12 months preoperatively were retrospectively reviewed (n = 47). Patients were categorized as vitamin D deficient (<30 ng/mL) vs normal (31-80 ng/mL). The primary outcome was the incidence of reoperation secondary to nonunion. Secondary outcomes included incidence of reoperation not related to nonunion and the need for repeat reoperation.

RESULTS

The average level in the vitamin D-deficient group (n = 17; 36.2%) was 16.9 vs 46.4 ng/mL in the normal group (n = 30; 63.8%). All recorded reoperations for nonunion occurred exclusively in the vitamin D-deficient cohort (4/17 [23.5%]; P = .013). There were similar reoperation rates for causes other than nonunion (2/17 [11.8%] vs 4/30 [13.3%]; P > .99) and repeat reoperation rates (3/17 [17.6%] vs 1/30 [3.3%]; P = .128) among vitamin D-deficient vs normal patients.

CONCLUSION

Vitamin D deficiency may be associated with an increased risk of reoperation for nonunion after ankle fusion.

Vitamin D Supplementation in Patients with Juvenile Idiopathic Arthritis

Vitamin D has been implicated in the pathogenesis of skeletal disorders and various autoimmune disorders. Vitamin D can be consumed from the diet or synthesized in the skin upon ultraviolet exposure and hydroxylation in the liver and kidneys. In its bioactive form, vitamin D exerts a potent immunomodulatory effect and is important for bone health. Juvenile idiopathic arthritis (JIA) is a collection of inflammatory joint diseases in children that share the manifestation of inflamed synovium, which can result in growth arrest, articular deformity, bone density loss, and disability. To evaluate the potential effect of vitamin D on JIA disease manifestations and outcomes, we review the role of vitamin D in bone metabolism, discuss the mechanism of vitamin D in modulating the innate and adaptive immune systems, evaluate the clinical significance of vitamin D in patients with JIA, and summarize the supplementation studies.

Suicide Risk in Rheumatoid Arthritis Patients is Associated With Suboptimal Vitamin D Levels

BACKGROUND/OBJECTIVE

Rheumatoid arthritis (RA) patients might experience anxiety and depressive symptoms. Deficient vitamin D levels may be a trigger for these conditions. The aim of this study was to determine the frequency of depression, anxiety symptoms, and suicidal risk or ideation in patients with RA associated with vitamin D serum levels.

METHODS

In this cross-sectional study, we recruited RA patients older than 18 years, classified into 3 groups according to serum vitamin D levels: sufficient, ≥30 ng/mL; insufficient, 20-29 ng/mL; and deficient, <20 ng/mL. Based on the self-reported Plutchik and the Hospital Anxiety and Depression Scale, we evaluated the association of suicidal risk, depression, and anxiety with the vitamin D levels in RA and the Rheumatoid Arthritis Quality-of-Life Questionnaire.

RESULTS

We studied 72 patients with RA between January and October 2019. We found an inverse correlation between Plutchik score and suicidal risk with inadequate vitamin D levels, but not with the Hospital Anxiety and Depression Scale. Suicidal ideation was associated with a higher score on the Rheumatoid Arthritis Quality-of-Life Questionnaire.

CONCLUSIONS

Despite the high prevalence of depressive and anxiety symptoms in RA patients, a Plutchik low correlation coefficient with inadequate serum levels of vitamin D was found. However, in the analysis of covariance, we were able to find that vitamin D levels remain associated with a reduction of suicide ideation. Further studies are needed to identify a risk profile for early psychological interventions to improve the quality of life in RA patients.

Health consequences of vitamin D deficiency in the human body

Vitamin D is extremely important for the proper functioning of the body. The most commonly known role of vitamin D is its participation in regulation of calcium-phosphate metabolism and bone mineralization. This role is crucial in the prevention of rickets in children and osteoporosis in the elderly. In recent years, numerous studies have confirmed the pleiotropic effects of vitamin D. Proper vitamin D levels in blood have a positive effect on overall health, thus reducing the risk of many diseases. Vitamin D plays, inter alia, a positive role in some diseases of the gastrointestinal tract (inflammatory bowel disease), nervous system (Parkinson disease, Alzheimer disease), and cardiovascular disease (atherosclerosis). Additionally, its positive protective effect in the case of neoplastic and immunological diseases has been noted. Some studies also confirm the relationship of vitamin D deficiency to obesity and depression. In the event of these diseases, it is possible to prevent disease and support the process of treatment by maintaining appropriate levels of 25(OH)D in the blood. Besides, sufficient blood vitamin D levels reduces the risk of developing respiratory tract infections and suppresses cytokine storm, which is responsible for most COVID-19 deaths.

The aim of the study was to present the current state of knowledge regarding the role of vitamin D in the human body, especially in the context of the impact of its abnormal level on the development of various diseases.