Indicator Of Vitamin Research Articles

Segmental analysis of human hair reveals intra-annual variation in 25(OH)D3 concentrations in modern and archaeological individuals

Vitamin D is essential for healthy skeletal growth and is increasingly recognised for its role in chronic disease development, inflammation and immunity. 25-hydroxyvitamin D3 (25(OH)D3) concentrations are an indicator of vitamin D status and are normally analysed in plasma or serum samples in clinical settings, while archaeological studies rely on the identification of skeletal markers of vitamin D deficiency, such as rickets. Here, we determined 25(OH)D3 concentrations in hair specimens (‘locks’) that had been sampled close to the root, aligned by cut end, and sliced into sequential segments from participants (n = 16), from Aberdeen, Scotland, using a modified protocol designed to minimise sample size. Concentrations were above detectable levels in 14 of 16 individuals, generating a (~ monthly) time-series of 25(OH)D3 concentrations, with fluctuating intra-hair trends consistent with the bioaccumulation of 25(OH)D3. In three participants, fluctuations in intra-hair 25(OH)D3 appear linked to recent significant weight loss, potentially due to the release of stored 25(OH)D3 from adipose tissue and subsequent uptake in hair. For the remaining participants, no statistically-significant correlations were determined between mean hair 25(OH)D3 levels and self-reported data, including age, sex, BMI, vitamin D supplementation, frequency of oily fish consumption, and hours spent outside. For a subset of our cohort (n = 4) isotope analysis highlighted potential relationships between elevated δ18O values (which can indicate season of hair growth) and 25(OH)D3 concentrations in some individuals, which may reflect seasonally-increased UVB exposure. We also present data from an archaeological individual from the same city, with the addition of further isotope analysis (carbon, nitrogen, sulphur) to characterise diet. Results suggest possible positive correspondence of 25(OH)D3 levels with season in this archaeological individual, and possibly with marine protein consumption, highlighting the potential use of this approach in characterising the relationship between past vitamin D levels and diet. While results are promising, we recognise the limits of this study in terms of sample size and use of self-reported data, and further work is needed to better understand the relationship between serum and hair 25(OH)D3 before this approach can further be developed as either a non-invasive medical test or an archaeo-investigative technique.

Prolonged prothrombin time in hyperemesis gravidarum as an indicator of vitamin K deficiency

AbstractAimMaternal vitamin K (VK) deficiency can lead to fetal complications such as cerebral hemorrhage and bone malformations. In this study, we aimed to analyze changes in prothrombin time (PT) and protein induced by VK absence or antagonist II (PIVKA‐II) in patients with severe hyperemesis gravidarum with suspected VK deficiency.MethodsWe compared 151 patients with severe hyperemesis gravidarum treated with intravenous nutrition to 46 patients undergoing cervical suturing or benign ovarian tumor surgery before mid‐pregnancy.ResultsIn the hyperemesis group, coagulation factors, including PT (s), prothrombin activity, INR, and APTT, showed a significant shift toward fibrinolysis compared to control (p < 0.001). The changes were within the normal range, except for PT (s), which was prolonged (14.6 ± 1.4 s). PIVKA‐II was measured 25 times in 11 cases of hyperemesis and significantly correlated with PT (s). Moreover, VK was supplemented in four cases with severe VK deficiency, promptly normalizing both PT (s) and PIVKA‐II.ConclusionsMonitoring VK deficiency using PT (s) and PIVKA‐II, with timely VK supplementation, may help prevent fetal complications in severe hyperemesis gravidarum.

Measurement of Serum Free Vitamin D Concentrations: Importance, Challenges, and the Emerging Role of Mass Spectrometry.

Serum total 25-hydroxyvitamin D [25(OH)D] concentration is the most widely used clinical biomarker for vitamin D status. Under certain physiological and pathological conditions, however, total 25(OH)D may not always be the best index for vitamin D status. Instead, the nonprotein-bound (free) fraction of total 25(OH)D has been suggested as a more appropriate marker in certain clinical situations. Free 25(OH)D levels can either be calculated or measured directly. Calculated free 25(OH)D depends on the concentrations of total serum 25(OH)D, vitamin D binding protein (VDBP), and albumin, as well as the affinity between analyte and binding proteins. Differences in VDBP concentrations are observed between populations as a result of health status, gene polymorphisms, and the assay used for determination. Direct measurement methods for free 25(OH)D are often complicated (dialysis, ultrafiltration) or susceptible to interferences, cross-reactivity, and type of antibody (immunoassays). Therefore, it is very important to develop tools that allow either accurate and precise measurement of VDBP or direct measurement of free 25(OH)D. For the latter, liquid chromatography combined with tandem mass spectrometry (LC-MS/MS) has recently shown promise for analysis of free vitamin D. In the current review, we present the importance and challenges regarding free 25(OH)D determination and the role of LC-MS-based methods in future studies. More research is required to determine the role of free 25(OH)D in the assessment of vitamin D status in healthy subjects and in various clinical conditions. Recent advances in technology, including mass spectrometry, can provide the required assays for this purpose.

Clinical Study of Vitamin D Levels in Hospitalized Children with Acute Respiratory Infections.

The aim of our research was to evaluate and analyze serum 25(OH) vitamin D and parathyroid hormone (PTH) levels to investigate whether vitamin D deficiency serves as a risk factor for an increased incidence of acute respiratory infections (ARI) in children. Serum PTH levels were used as an indicator of vitamin D sufficiency, as normal PTH levels require an optimal concentration of 25(OH) vitamin D. The study included 129 children, divided into five subgroups: children with acute bronchopneumonia (n = 42), acute laryngotracheitis (n = 7), acute bronchiolitis (n = 32), acute bronchitis (n = 18), and a control group (n = 30). No statistically significant differences in 25(OH)D levels were observed between the overall population of children with ARI and the control group (p = 0.073). However, significant differences in 25(OH)D levels were identified between the control group and children with bronchopneumonia, acute bronchitis, and laryngotracheitis (p < 0.01, p < 0.05). Regarding PTH levels, statistical significance was found between the control group and the acute bronchiolitis group, due to the high percentage of children with hypervitaminosis in this subgroup. These results highlight the crucial role of vitamin D in the onset and progression of acute respiratory tract infections in children, emphasizing its impact on their overall respiratory health.

Exploring factors associated with vitamin D nutritional status in Japanese baseball players.

Vitamin D is a nutrient necessary for conditioning athletes. This cross-sectional study aimed to determine the nutritional status of vitamin D in farm-league professional baseball players to examine vitamin D requirements. This study included 35 players enrolled in farm team A of the Nippon Professional Baseball Organization in the spring of 2022. The survey items included anthropometric measurements, serum 25-hydroxyvitamin D [25(OH)D] levels as an indicator of vitamin D nutritional status, a simple questionnaire for predicting vitamin D deficiency in Japanese adults, mean daily sun exposure duration, and body surface area (BSA). The serum 25(OH)D level was 29.8±1.8 ng/mL, and 17 (49%) participants were vitamin D deficient (<30 ng/mL). The serum 25(OH)D levels showed positive correlations with body height (r=0.459, P<0.01), fat-free mass (r=0.347, P<0.05), muscle mass (r=0.341, P<0.05), and BSA (r=0.434, P<0.01). Furthermore, the consumption frequency of fish with high vitamin D levels in regular diets, BSA, and body fat mass were identified as predictors of the serum nutritional status of vitamin D. Athletes engaged in outdoor sports, such as the study participants, had inadequate vitamin D levels. In addition, the frequency of consumption of fish with high vitamin D levels in regular diets, BSA, and body fat mass were identified as predictors of the serum nutritional status of vitamin D. Further studies of the relationship between vitamin D supplementation and performance are needed.

Saturation association between serum 25-hydroxyvitamin D levels and mortality in elderly people with hyperlipidemia: a population-based study from the NHANES (2001-2016).

25-hydroxyvitamin D is the body's main storage form of vitamin D and is internationally recognized as the best indicator of vitamin D status in the human body. There is a scarcity of research investigating the interrelationship between serum 25-hydroxyvitamin D (25(OH)D) levels and mortality among elderly individuals with hyperlipidemia. To address this knowledge gap, we examined the association between serum 25(OH)D levels and mortality in an older hyperlipidemic population from NHANES, while controlling for other influential factors. The study sought to elucidate the correlation between serum 25(OH)D levels and mortality about all-cause mortality, cardiovascular disease (CVD), malignant neoplasms, and mortality from other causes. The data from NHANES 2001-2016, including 9,271 participants were analyzed to examine the association between serum 25(OH)D levels and mortality. The interrelationship was illustrated using Kaplan-Meier curves and restricted cubic splines, while the Cox proportional hazards model was utilized to estimate the multifactor adjusted hazard ratio (HR). This study included 9,271 participants (43.28% male) with an average age of 69.58 years, and the average duration of participant follow-up was 88.37 months. Kaplan-Meier curves demonstrated that lower serum 25(OH)D levels were associated with increased risks of all-cause mortality, cardiovascular mortality, malignant neoplasm mortality, and mortality from other causes. This negative association was further confirmed by the Cox proportional hazards models. Additionally, restricted cubic splines not only revealed this negative association but also highlighted the saturated serum 25(OH)D levels. Moreover, subgroup analyses indicated that the inverse correlation between serum 25(OH)D levels and all-cause mortality was more pronounced in the non-obese and smoking population. And the inverse correlation with mortality from other causes was even stronger in the non-obese population. In the elderly population with hyperlipidemia, 25(OH)D serum levels were negatively correlated with both cause-specific mortality and all-cause mortality. Moreover, there was a threshold effect in this negative association.

B-001 Serum 25-hydroxyvitamin D and C-3 epimer concentrations throughout gestation in a bovine dairy herd

Abstract Background Serum 25-hydroxyvitamin D (25(OH)D) serves as an indicator of vitamin D status in most animal species. The recent identification of its C-3 epimer, 3-epi-25-hydroxyvitamin D3 (3-epi-25(OH)D3) remains diagnostically confounding. The appearance of this epimer in blood serum has been reported for both pregnant women and infants; however, because of its recent discovery, its physiologic role, biochemical regulation, and overall biologic importance have yet to be fully elucidated. Given its prevalence in pregnant women, it was hypothesized that 3-epi-25(OH)D3 may serve as a novel predictive biomarker of pregnancy in animals. Methods In the current study, we validated an LC-MS/MS method to measure the mono-hydroxyvitamin D metabolites 25-hydroxyvitamin D2 (25(OH)D2), 25-hydroxyvitamin D3 (25(OH)D3), and 3-epi-25(OH)D3, in bovine serum. Serum was collected from dairy cows at six stages of pregnancy (n=60 (10 per group), pre-breeding heifers, 30-40 days pregnant, 70-90 days, 120-180 days, 210-260 days, and 30-45 days post-calving). The 25(OH)D metabolites were extracted from serum by supported liquid extraction (SLE) and the eluate was derivatized with 2-Nitrosopyridine. Derivatized samples were introduced to the LC-MS/MS, ionized by electrospray ionization in positive-ion mode, and detected and quantified by multiple-reaction monitoring. Results The LC-MS/MS method was linear in the concentration range of 0.25 ng/mL to 100 ng/mL with an r2 &amp;gt; 0.99 for each analyte. 3-epi-25(OH)D3 and total serum 25(OH)D concentrations were calculated for each stage of pregnancy. Pre-bred heifers had serum 25(OH)D concentrations ranging from 65 - 85 ng/mL with trends toward non-significant increases with mean values approaching 100 ng/mL during pregnancy. Interestingly, 3-epi-25(OH)D3 remained near baseline (1.3 - 1.9 ng/mL) for the first 90 days and elevated 3- to 4-fold thereafter. Conclusions This study confirms that epimerization of 25(OH)D3 is a conserved biochemical process across species. While not predictive of pregnancy itself, the increase in circulating 3-epi-25(OH)D3 concentrations was consistent with mid- to late-gestational increases in estrogen concentration observed for dairy cattle. Future studies will explore the potential link between increases in gestational estrogen and epimerization.

Vitamin D levels and bone mineral density of middle-aged premenopausal female football and volleyball players in Japan: a cross-sectional study

BackgroundThe number of football teams in senior categories has increased. As outdoor sports entail players being exposed to sunlight, playing football may contribute to maintaining vitamin D stores and body mineral density while preventing osteoporosis. This study aimed to determine the bone mineral density and vitamin D levels in middle-aged premenopausal female football players.MethodsParticipants were premenopausal females in their 40s. We evaluated bone mineral density of the second to the fourth lumbar vertebrae and femoral neck, serum 25-hydroxy vitamin D (25-OHD) levels, which is an indicator of vitamin D stores, and body composition. In addition, we administered a questionnaire survey on exercise habits and lifestyle. Ninety-two participants were categorised into three groups: the football group (n = 27), volleyball group (n = 40), and non-exercise group (n = 25).ResultsBone mineral density was higher in the football and volleyball groups than in the non-exercise group (P < 0.01). The volleyball group had a significantly higher bone mineral density of the lumbar spine and femoral neck than the non-exercise group (P < 0.01). The football group had a significantly higher bone mineral density of the femoral neck than the non-exercise group (P < 0.01). Although the football group had played fewer years than the volleyball group (P < 0.01), serum 25-OHD levels were the highest in the football group and were significantly higher than those in the volleyball and non-exercise groups (P < 0.01).ConclusionsMiddle-aged premenopausal football players had higher body vitamin D levels and bone mineral densities than non-active females. These results suggest that playing football may contribute to the prevention of osteoporosis.Trial registrationUMIN Clinical Trials Registry UMIN000054235. 2024/04/23. Retrospectively registered.

Extrahepatic Vitamin K-Dependent Gla-Proteins-Potential Cardiometabolic Biomarkers.

One mechanism to regulate pathological vascular calcification (VC) is its active inhibition. Loss or inactivation of endogenic inhibitors is a major inductor of VC. Such inhibitors are proteins rich in gamma-glutamyl residues (Gla-proteins), whose function strongly depends on vitamin K. The current narrative review is focused on discussing the role of extrahepatic vitamin K-dependent Gla-proteins (osteocalcin, OC; matrix Gla-protein, MGP; Gla-rich protein, GRP) in cardio-vascular pathology. Gla-proteins possess several functionally active forms whose role in the pathogenesis of VC is still unclear. It is assumed that low circulating non-phosphorylated MGP is an indicator of active calcification and could be a novel biomarker of prevalent VC. High circulating completely inactive MGP is proposed as a novel risk factor for cardio-vascular events, disease progression, mortality, and vitamin K deficiency. The ratio between uncarboxylated (ucOC) and carboxylated (cOC) OC is considered as an indicator of vitamin K status indirectly reflecting arterial calcium. Despite the evidence that OC is an important energy metabolic regulator, its role on global cardio-vascular risk remains unclear. GRP acts as a molecular mediator between inflammation and calcification and may emerge as a novel biomarker playing a key role in these processes. Gla-proteins benefit clinical practice as inhibitors of VC, modifiable by dietary factors.

Relation between Polygenic Risk Score, Vitamin D Status and BMI-for-Age z Score in Chinese Preschool Children.

Both genetics and vitamin D deficiency are associated with childhood obesity. However, the role of vitamin D status between polygenic and childhood obesity has been unknown. The current study aimed to determine the relation between genetic factors, vitamin D status, and BMI-for-age z score (zBMI) in Chinese preschool children. A total of 1046 participants aged 3.7 to 6.6 years old from the Long-term Health Effects Assessment Project of Infants and Toddlers Nutritional Pack (LHEAPITNP) were included in this study. The polygenic risk score (PRS) was established based on 55 BMI-related single nucleotide polymorphisms (SNPs) derived from a published genome-wide association study (GWAS) for BMI. Serum 25(OH)D was used as an index of vitamin D status and measured with liquid chromatography-tandem mass spectrometry (LC/MS-MS) assay. The Wilcoxon test or Kruskal-Wallis test was used to compare the differences of variables between different groups and Spearman correlation analysis was used for analyzing the correlations between the PRS, 25(OH)D levels, and zBMI. The PRS showed a positive relation to zBMI (rs = 0.0953, p = 0.0022) and 25(OH)D showed a negative relation to zBMI (rs = -0.1082, p = 0.0005) in the full-adjustment model. In addition, the differences in zBMI at different vitamin D statuses in the low-risk PRS group and the intermediate-risk PRS group were both statistically significant (plow = 0.0308, pintermediate = 0.0121), the median zBMI was both higher at vitamin D insufficiency status. And the difference in zBMI between different genetic risk groups was also statistically significant at vitamin D sufficiency status (p = 0.0077). Furthermore, genetic risk showed a positive relation to zBMI at vitamin D sufficiency status, and the p for trend was 0.0028. Our findings suggested that vitamin D was related to zBMI negatively in Chinese preschoolers and maintaining adequate vitamin D levels may only contribute to lower the zBMI in preschoolers with low and intermediate genetic susceptibility.

A comparative study on indicators of vitamin A status and risk factors for sensitivity and specificity of the methods to detect vitamin A deficiency

BackgroundSerum retinol (SR) and retinol-binding protein (RBP) are commonly used indicators, but they are affected by infections and inflammation. This study aimed to assess the sensitivity and specificity of VA indicators to detect vitamin A deficiency (VAD) in 36–59-month-old children living in a rural area in Burkina Faso.MethodsIn a community-based study, two cross-sectional surveys were carried out from November 2016 to September 2017 in the health district of Dandé in Burkina Faso. The surveys included 115 children 36–59 months old. Indicators of VA and inflammation assessed in all children included SR, RBP and total liver VA reserves (TLR) estimated by retinol isotope dilution, and inflammation markers (C-reactive protein (CRP) and alpha 1-acid glycoprotein (AGP)). We calculated the sensitivity, specificity, positive and negative predictive values. In addition, the effects of inflammation, helminth infection, and season on sensitivity and specificity were assessed.ResultsThe prevalence of VAD assessed by SR (< 0.7 µmol/L), RBP (< 0.7 µmol/L), and TLR (< 0.1 µmol/g liver) were, respectively, 30.9%, 33.3%, and 0%. Compared to TLR, the specificity, positive predictive value, and negative predictive value of SR were 71.1%, 0%, and 100%, and of RBP, were 68.9%, 0%, and 100%, respectively. The sensitivity was indeterminable for SR and RBP. The specificity of SR and RBP was lower during the dry season. Elevated CRP (> 5.0 mg/L) and AGP (> 1.0 g/L) were detected in 1.9% and 28.6% of children, respectively. The adjustment of VA indicators for inflammation improved SR’s specificity to 75.9% and decreased RBP’s specificity to 67.8%.ConclusionNo cases of VAD were identified by TLR. However, (inflammation-adjusted) SR and RBP had varying accuracy in the estimation of VAD.Trial registrationThe study was registered, retrospectively, on 22 March 2018 as a clinical trial with the Pan African Clinical Trials Registry under the number Cochrane South Africa; PACTR201803002999356.

Vitamin D status and 12-year mortality risk after myocardial infarction

Abstract Introduction Vitamin D deficiency has been associated with an increased risk of cardiovascular disease (CVD) mortality in healthy populations. Whether this association is also present in patients with established CVD is not yet clear. Purpose We examined the association of serum 25-hydroxyvitamin D [25(OH)D] as an indicator of vitamin D status with 12-year risk of CVD and all-cause mortality in post-myocardial infarction (MI) patients. Methods A prospective analysis was carried out in 4,479 Dutch patients from the Alpha Omega Cohort (aged 60-80 y) who had an MI ≤10 y prior to study enrolment. Non-fasting venous blood was sampled at baseline (2002-2006) for the assessment of 25(OH)D using LC-MS/MS. Patients were followed for cause-specific mortality through December 2018. Hazard ratios (HRs) for CVD and all-cause mortality were obtained in sex-specific 25(OH)D tertiles using Cox regression models, adjusted for age, education, physical activity, smoking status, alcohol intake, adherence to dietary guidelines (i.e. 2015 Dutch Healthy Diet index [DHD15]), prevalent diabetes and kidney function (eGFR). Restricted cubic splines (RCS) analysis was performed for continuous associations, using median 25(OH)D as the reference. Results Patients were 69.0 ± 5.6 y old, 78% was male, 17% were current smokers, 18% had diabetes and 8% used vitamin-D containing supplements. A total of 2,091 deaths occurred during a median follow-up period of 12.4 y (49,529 person-years), including 924 from CVD as a primary or contributing cause. Median 25(OH)D was 21.3 ng/mL, and tertile cut-offs were 18.3 and 26.2 ng/mL for males and 15.2 and 22.0 ng/mL for females. Of the cohort, 44% were vitamin D deficient (&amp;lt;20 ng/mL). Lower risks of CVD mortality were observed in the mid tertile (HR: 0.76, 95%CI:0.65-0.88) and upper tertile (HR: 0.67, 95%CI:0.57-0.79) of 25(OH)D, compared to the lower tertile. RCS showed a roughly linear association (P-non-linearity = 0.08), with a 11% lower risk of CVD mortality per 5 ng/mL-increment in 25(OH)D (HR: 0.89, 95%CI: 0.86-0.93). Inverse associations were more pronounced in patients with a higher calcium intake (&amp;gt;845 g/d; 0.87, 95%CI:0.96-0.98; per 5 ng/mL) and in patients who were more physically active (HR: 0.88, 95%CI: 0.83-0.93; per 5 ng/mL). Exclusion of 378 vitamin D supplement users did not materially change the associations. For all-cause mortality, multivariable HRs were 0.74 (95%CI: 0.67-0.82) in the mid tertile, and 0.65 (95%CI: 0.58-0.73) in the upper tertile, compared to the lower tertile. Conclusion A low vitamin D serum concentration is related to a higher risk of recurrent CVD and all-cause mortality in patients with coronary artery disease. Causality remains to be determined preferably in a clinical trial to evaluate the effect of oral suppletion of vitamin D on recurrent CVD and mortality risk in these patients.

Vitamin and microelement status and somato­sexual development of adolescents with type 1 diabetes

Objective — to study peculiarities of the state of vitamin and microelement provision in children and adolescents with type 1 diabetes with the physiological and pathological course of puberty.&#x0D; Materials and methods. The study involved 143 patients (75 boys and 68 girls) with type 1 diabetes aged 10 to 17 years. The level of retinol, tocopherol, 25(OH)D3 and Zn concentration were determined in blood serum.Results and discussion. The gender characteristics of vitamin and microelement imbalance in adolescents with type type 1 diabetes were determined, the nature of which depended on the course of puberty. Among boys with type 1 diabetes under the conditions of harmonious physical development (PD), an increase in the percentage of low levels of vitamin E was recorded more often than in girls (39.1 vs. 12.2 %, рφ &lt; 0.02). In girls with a disharmonious type of PD with increased body weight and high height, there was an increase in the frequency of high levels of vitamin E (48.1 %) under conditions of a normal level of retinol (37.0 %). In boys with high height and body weight disorders, an increased level of Zn (64.3 %) and an increase in the frequency of pronounced vitamin D deficiency (47.6 %) were recorded more often. Only 9.5 % of patients had vitamin D levels that corresponded to the optimal level of provision. In girls with disharmonious PD, the level of 25(OH)D3 was higher than in boys and was (19.06 ± 1.51) and (13.10 ± 1.53) ng/ml, respectively; (рu &lt; 0.002). Under the conditions of disharmonious PD boys had lower values of vitamin A (52.2 vs. 29.6 %, рφ &lt; 0.05) and vitamin E (39.1 vs. 3.7 %, рφ &lt; 0.05) compared to girls. In boys with the physiological course of sexual development (SD), in comparison with girls, a decrease in the level of zinc, retinol and tocopherol was more often registered. Under the conditions of SD disorders, a reduced level of vitamin A was more often registered in girls (66.7 vs. 35.7 %, рφ &lt; 0.03) with a simultaneous decrease in the frequency of its elevated values (8.3 vs. 37.5 %, рφ &lt; 0.01) relative to patients with a physiological course of SD. At the same time, normal levels of vitamin E were recorded more often. Under conditions of sexual development delay in boys, the frequency of normal values of vitamin E was decreased compared to girls. Аt the same time, pronounced deficiency of vitamin D was more often registered in boys with a simultaneous decrease in the frequency of its suboptimal level.&#x0D; Conclusions. Based on the results of the study, a relationship between indicators of vitamin and microelement status and somatic and sexual development in adolescents with type I diabetes was established. The tension of reserves of vitamins A, E, D and the imbalance of zinc concentration were found in boys with disharmonious physical development. Sexual development delay in boys was accompanied by a deterioration in the nature of providing the body with vitamins D and E.

Predicting comorbidities of pregnancy: A comparison between total and free 25(OH)D and their associations with parathyroid hormone

Pregnancy is a unique time when amplified sex steroid concentrations promote an escalation in vitamin D binding protein (DBP) synthesis, associated with increased total vitamin D and metabolites, including 25-hydroxyvitamin D (25(OH)D). Free 25(OH)D concentration increases disproportionately to total 25(OH)D during pregnancy, likely an adaptation to supply the woman and fetus with readily available 25(OH)D. Highlighting the importance of the calcium metabolic stress during pregnancy, the interactional relationship between serum 25(OH)D and PTH has been evaluated. Maternal total 25(OH)D and total 25(OH)D/iPTH are measures of vitamin D status and biomarkers for potential pregnancy complications. It has been proposed that free 25(OH)D and free 25(OH)D/iPTH could be better indicators of vitamin D status and predictors of pregnancy complications such as gestational diabetes (GDM), hypertensive disorders of pregnancy, and preterm delivery. This study aims to determine if free 25(OH)D and its association with PTH are more accurate predictors of comorbidities of pregnancy than total 25(OH)D and its association with PTH. In this post hoc analysis of the Kellogg Pregnancy Study, a double-blind randomized placebo-controlled trial, participants included 297 women with singleton pregnancies: 191 participants were randomized into a group receiving a daily prenatal (400 IU vitamin D3) while 196 received a prenatal plus extra supplementation (4400 IU vitamin D3). Blood and urine samples were collected monthly. 297 participants’ serum total 25(OH)D concentrations were measured using radioimmunoassay at baseline (visit 1) and 5–7 months’ gestation (visit 6–7). 93 participants’ serum free 25(OH)D and PTH concentrations were measured using ELISA and immunoradiometric assay, respectively, at visit 1 and 6–7; 66 participants had paired samples and were included in this analysis. Data were analyzed using SAS 9.4, Cary, N.C. or SPSS v28, IBM Corporation, Armonk, N.Y. Results were considered significant with a p < 0.05. A significant relationship exists between the ratio of total 25(OH)D/iPTH and free 25(OH)D/iPTH grouped by total 25(OH)D ≥ 30 ng/mL and < 30 ng/mL as an indicator of maternal vitamin D status. There was a statistically significant relationship between lower mean free 25(OH)D/iPTH and the development of GDM at visit 1 (p = 0.0003) and at visit 6–7 (p = 0.001) while total 25(OH)D/iPTH and GDM were significantly related only at visit 1 (p = 0.029). In this exploratory cohort, neither free 25(OH)D/iPTH nor total 25(OH)D/iPTH were significantly associated with increased incidence of preterm delivery, hypertensive disorders, or combined comorbidities of pregnancy. An univariate logistic regression evaluating the outcome of gestational diabetes while independently controlling for independent factors showed the ratio of free 25(OH)D/iPTH was more closely associated with gestational diabetes than the ratio of total 25(OH)D/iPTH, although neither were significant. This proof-of-concept analysis suggests that the ratio of free 25(OH)D/iPTH is associated with the development of gestational diabetes throughout pregnancy while total 25(OH)D/iPTH is only associated with the outcome early in pregnancy. Further investigation is warranted to explore this relationship between calcium metabolic stress during pregnancy with a larger cohort to improve validity,reproducibility, and relevance to other pregnancy comorbidities.

Studing of the composition of plant raw materials for the development of a recipe for a new type of feed

The article examines the chemical composition of some types of grain crops – wheat, bran, barley to identify the most nutritious of them, mixed with a feed additive to obtain highly nutritious feed for cattle. According to laboratory studies, the selected raw materials exceed the most common types of feed in terms of mineral content. Bran has the best indicators of vitamin and mineral composition, but the content of fiber and ash in them is higher than in wheat and barley, which can negatively affect the digestibility of ruminants. Wheat has the lowest indicators in terms of the content of the mass fraction of fiber and ash: fiber – 10.44%, ash – 1.57%. The content of the mass fraction of fat in the studied raw materials is in the range of 2.13-3.62%. Consequently, 3.5-4% of animals or a mixture of animal and vegetable fats protected from decay in the rumen can be added to the cow's diet. Comparing the data obtained with the minimum requirements for fodder crops and feed quality in the production of milk and beef, the compliance of the actual results with the requirements of regulatory documents was revealed. Based on the data obtained, it is concluded that it is possible to use this raw material as the main raw material for the development of compound feed with increased nutritional value.

Rational Design of Trident Aptamer Scaffold for Rapid and Accurate Monitoring of 25-Hydroxyvitamin D3 Metabolism in Living Cells.

The level of 25-hydroxyvitamin D3 [25(OH)VD3] in human blood is considered as the best indicator of vitamin D status, and its deficiency or excess can lead to various health problems. Current methods for monitoring 25(OH)VD3 metabolism in living cells have limitations in terms of sensitivity and specificity and are often expensive and time-consuming. To address these issues, an innovative trident scaffold-assisted aptasensor (TSA) system has been developed for the online quantitative monitoring of 25(OH)VD3 in complex biological environments. Through the computer-aided design, the TSA system includes an aptamer molecule recognition layer that is uniformly oriented, maximizing binding site availability, and enhancing sensitivity. The TSA system achieved the direct, highly sensitive, and selective detection of 25(OH)VD3 over a wide concentration range (17.4-12,800 nM), with a limit of detection of 17.4 nM. Moreover, we evaluated the efficacy of the system in monitoring the biotransformation of 25(OH)VD3 in human liver cancer cells (HepG2) and normal liver cells (L-02), demonstrating its potential as a platform for drug-drug interaction studies and candidate drug screening.

A Retrospective Chart Review Evaluating Changes in 25-Hydroxyvitamin D Levels among Patients Attending the University Healthcare Centre during the COVID-19 Pandemic.

COVID-19-pandemic-related home confinement aids in limiting the spread of the virus but restricts exposure to sunlight, thereby possibly affecting 25(OH)D concentrations. This study aimed to investigate the effect of lockdown measures on 25(OH)D levels in outpatients visiting the healthcare centre over a period of two years. In this retrospective chart review, outpatients who visited a university healthcare centre for a health check-up over a period of two years were included. The patients' 25(OH)D serum levels and status were compared before, during, and after the lockdown periods. A total of 7234 patients were included in this study, with a mean age of 34.66 ± 16.78. The overall prevalence of 25(OH)D insufficiency, deficiency and sufficiency was 33.8%, 30.7% and 35.4%, respectively. The proportion of individuals with 25-(OH) D deficiency prior to lockdown was 29% and this proportion increased in the lockdown and post-lockdown periods to 31.1% and 32%, respectively. Although gender was less likely to have an impact on the 25 (OH) D level during the lockdown period (p = 0.630), we found an association between gender and 25 (OH) D status in the pre-lockdown and post-lockdown periods (p < 0.001 and p < 0.001, respectively). Another association between nationality and 25 (OH)D levels was found before, during and after the lockdown periods (p < 0.001). In addition, the youngest population, aged between 1 and 14, was strongly affected by the home confinement. Age had a positive and significant (p < 0.05) effect on 25 (OH) D status regardless of the different periods. Moreover, in the pre-lockdown period, male outpatients had 1.56 chance of having a sufficient level of 25 (OH)D. However, during the lockdown period, this chance decreased to 0.85 and then increased to 0.99 after the lockdown period. We found no statistically significant difference in the mean serum concentrations or in the prevalence of vitamin D insufficiency when we compared values from before, during and immediately after the COVID-19 lockdown period. However, there was a generally increased prevalence of vitamin D insufficiency in our study population. Another association between gender, nationality and age groups with 25(OH) D was found. Regular exposure to UVR is recommended for maintaining adequate vitamin D levels and to prevent vitamin D deficiency. Further research is needed to determine the best indications for vitamin D supplementation if confinement periods are extended and to consider the potential health consequences of prolonged confinement periods not only on vitamin D status but also on overall public health. The findings of this study may be considered by stakeholders for a targeted supplementation approach for risk groups.

Dietary Calcium Levels and Treatment Interval Determine the Effects of Lead Ingestion on Plasma 1,25-Dihydroxyvitamin D Concentration in Chicks

The combined effects of dietary calcium level and lead level on several indices of vitamin D endocrine function were examined in young, growing chicks. Day-old animals fed a nutritionally adequate diet for 2 wk were fed diets either adequate (1.2%) or low (0.1%) in calcium, and containing 0, 0.2 or 0.8% lead for an additional 1 or 2 wk. In the calcium-adequate group, lead ingestion significantly elevated intestinal calbindin-D28k protein and mRNA levels as well as plasma 1,25-dihydroxyvitamin D concentration compared with the control animals fed a lead-free diet. The effect was apparent after 1 wk of treatment and continued through wk 2. In the calcium-deficient group, the early (1 wk) increases in plasma 1,25-dihydroxyvitamin D and calbindin-D28k protein and mRNA were significantly reversed by lead ingestion over the 2-wk trial period in a dose-dependent fashion. In these circumstances, vitamin D endocrine function is severely compromised. Therefore, lead ingestion may result in either enhanced or diminished circulating 1,25-dihydroxyvitamin D concentrations and ensuing intestinal responses, depending of dietary calcium level and the duration of lead intake. These results provide possible explanations for several apparently conflicting sets of observations regarding lead-calcium interactions.

Role of plasma calcium, phosphorus, alkaline phosphatase, and parathyroid ‎hormone in the prediction of vitamin D deficiency‎

Vitamin D deficiency is a highly prevalent medical condition associated with various clinical and biochemical outcomes although these outcomes might be absent in a significant percentage of patients. Altered serum calcium, phosphorus, parathyroid hormone and alkaline phosphatase activity are expected but not proven by many research. The current study aims to investigate the possibility of these biomarkers to be used as indicators of vitamin D deficiency or insufficiency. The study enrolled 150 randomly selected participants who have no acute or chronic medical condition with various levels of serum vitamin D ranging from normal to severely deficient. They were investigated for serum total calcium, phosphorus, parathyroid hormone and alkaline phosphatase activity. The results were statistically compared among the studied groups and correlated with serum vitamin D levels. There was no significant difference in mean serum calcium, phosphorus and alkaline phosphatase activity among the groups with poor correlation with vitamin D. Mean serum parathyroid hormone has shown a significant difference among the studied groups with a strong negative correlation with vitamin D. This difference was apparent even in patients with vitamin D insufficiency. Serum calcium, PO4 and ALP activity seem to have a poor correlation with vitamin D concentration. In addition, serum PTH might be considered a sensitive marker of both vitamin D deficiency and insufficiency.

PSUN112 Expression of Vitamin D Receptor Pathway Genes Across Tissues of Individuals with Obesity

Abstract Introduction Vitamin D deficiency is a substantial comorbidity in 50% of pediatric patients and is linked with poorer health outcomes in children. Vitamin D levels are inversely related to BMI. Therefore, the prevalence of children with low vitamin D levels is increasing as the prevalence of pediatric obesity increases. Pediatric patients with obesity and vitamin D deficiency also have a uniquely increased risk of metabolic syndrome, as compared to their lean peers. However, measured levels of vitamin D correlate with other physiological markers of vitamin D effects in lean individuals but not obese individuals. Since vitamin D levels measured as 25-hydroxyvitmain D (serum 25(OH)D) reflect a storage form of vitamin D, their levels may not be a true reflection of vitamin D action in the body in an obese population. The aim of this study was to provide foundational knowledge to understand if expression of vitamin D receptor (VDR)-target genes in different metabolic pathways correlate with each other in diverse tissues, and thus may be used as a reference standard for vitamin D action in the body. Methods We performed a secondary analysis of samples obtained from 89 obese adolescents aged 12 to 18 years old that were consented under a past IRB-approved protocol. The samples were collected at the time of bariatric surgery between 2004 and 2019. Subject data included age, gender, race/ethnicity, and BMI. Samples collected included blood, intestinal, and subcutaneous adipose tissue. The tissues were analyzed via Real Time-PCR to obtain quantitative levels of VDR-target gene expression, which included TLR4, THBD, and VDR in subcutaneous adipose tissue; and TRPV6, S100G, and VDR in intestinal tissue. Gene expression levels were normalized to the average of two housekeeping genes, GAPDH and RPLPO. Blood samples were analyzed for vitamin D levels. Results VDR-target gene expression of THBD, VDR, and TLR4 in subcutaneous adipose tissue was significantly correlated (p &amp;lt;0.05). In intestinal tissue, we also saw significant correlation between TRPV6, S100G, and VDR (p &amp;lt;0.05). THBD, TLR4, TRPV6, S100G, and VDR gene expression levels from the respective tissues did not correlate with circulating serum 25(OH)D levels (p &amp;gt;0.05). Conclusion These important preliminary findings show VDR-target genes have correlated expression patterns within different tissues – one which stores vitamin D (adipose) and one which doesn't (intestinal). Interestingly, the VDR-target gene expression levels correlated with each other despite the genes being involved in different metabolic pathways in diverse tissues. These findings also show that VDR-target gene expression does not correlate with circulating serum 25(OH)D levels. This discrepancy supports that 25(OH)D levels do not indicate levels of vitamin D action and may not be an appropriate indicator of vitamin D deficiency in the obese population. Thus, VDR-target gene expression levels may provide a better reference standard for vitamin D action in the body. This study may provide the first step in determining a new and more accurate biomarker for vitamin D deficiency and treatment in obesity. Presentation: Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.