Poor bioavailability of vitamin D2 from ultraviolet-irradiated D2-rich yeast in rats

Ultraviolet-irradiated yeast (Saccharomyces cerevisiae) can be used to biofortify bakery products with vitamin D, but in bread, it was not effective in increasing serum 25-hydroxyvitamin D [25(OH)D] in humans, possibly because of the low digestibility of the yeast matrix. We investigated the effects of vitamin D-2-rich intact yeast cells and their separated fraction, yeast cell walls, which we hypothesized to provide vitamin D-2 in a more bioavailable form, on serum 25(OH)D and its metabolites in growing female Sprague-Dawley rats (n = 54) compared to vitamin D-2 and D-3 supplements (8 treatment groups: 300 or 600 IU vitamin D/d, and a control group, 8-week intervention). The D-3 supplement groups had the highest 25(OH)D concentrations, and the vitamin D-2 supplement at the 600-IU dose increased 25(OH)D better than any yeast form (P .05). Serum 24,25-dihydroxyvitamin D (a vitamin D catabolite) concentrations and the trend in the differences between the groups were in line with 25 (OH)D (P .05). These findings do not support the hypothesis: the ability of the different ultraviolet-treated vitamin D-2-containing yeast forms to increase 25(OH)D did not differ, and the poor bioavailability of vitamin D-2 in the yeasts compared D-3 or D-2 supplements could not be explained by the increased vitamin D catabolism in the yeast-treated groups. (C) 2018 Elsevier Inc. All rights reserved.Peer reviewe

Improved accuracy of an tandem liquid chromatography–mass spectrometry method measuring 24R,25-dihydroxyvitamin D3 and 25-hydroxyvitamin D metabolites in serum using unspiked controls and its application to determining cross-reactivity of a chemiluminescent microparticle immunoassay

Measurement of serum 25-hydroxyvitamin D [25(OH)D] is considered the best indicator of vitamin D status. Two minor vitamin D metabolites are common interferences encountered in 25(OH)D assays. The first is 3-epi-25-hydroxyvitamin D3 [3-epi-25(OH)D3], which if not chromatographically resolved from 25-hydroxyvitamin D3 [25(OH)D3], can overestimate 25(OH)D concentrations. The second is 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3], which can cross-react with the antibodies in 25(OH)D immunoassays. Our aim was to develop an LCâ MS/MS method capable of detecting both 3-epi-25(OH)D3 and 24R,25(OH)2D3 in serum without the use of a derivatization agent. We report an isotope dilution LCâ MS/MS method, with electrospray ionization in the positive mode, that can simultaneously detect 24R,25(OH)2D3, 25(OH)D3, 3-epi-25(OH)D3, and 25-hydroxyvitamin D2. The method employs a cost-effective liquidâ liquid extraction using only 150 μL of sera and a total run time of 10 min. Method performance was assessed by using quality controls made from pooled sera as an alternative to sera spiked with analytes. Biobanked samples, originally analyzed by chemiluminescent microparticle immunoassay (CMIA), were re-analyzed with this method to determine the contribution of 24R,25(OH)2D3 cross-reactivity to 25(OH)D measurement bias. The CMIA over-estimation of 25(OH)D measurements relative to LCâ MS/MS was found to depend on both 25(OH)D and 24R,25(OH)2D3 concentrations

C3-epimerization of 25-hydroxyvitamin D increases with increasing serum 25-hydroxyvitamin D levels and shows a high degree of tracking over time

Objective: Evaluate the effects of serum 25-hydroxyvitamin D (25(OH)D) levels, vitamin D binding protein (DBP) and genetic factors on C3-epimerization of 25(OH)D and follow the tracking of the epimer during one year. Design: Cross-sectional and longitudinal study. Methods: Data from eight previously conducted, Tromsø based studies (3 observational, 5 randomized controlled trials) were combined. 25(OH)D serum samples were re-analyzed with a LC-MS/MS method that also resolves and measures the metabolite C3-epi-25(OH)D3. Data on vitamin D binding protein (DBP) phenotype (based on single nucleotide polymorphisms (SNPs) rs4588 and rs7041) and genetic determinants for serum 25(OH)D (SNPs rs2282679, rs10741657, rs3829251 and rs6013897) were collected where available. Results: 2219 subjects were included. Median (5th, 95th percentiles) baseline serum values of 25(OH)D3, C3-epi-25(OH)D3, and %-C3-epi-25(OH)D3 were 49.1 (22.1, 92.8) nmol/L, 2.3 (0.9, 6.0) nmol/L and 4.4 (2.7, 8.4) %, respectively. The highest baseline values were 230.5 nmol/L for 25(OH)D3, 79.7 nmol/L for C3-epi-25(OH)D3 and 48.2% for %-C3-epi-25(OH)D3. There was a strong correlation between serum 25(OH)D3 and C3-epi-25(OH)D3. The %-C3-epi-25(OH)D3 value increased with increasing serum 25(OH)D3, but leveled off at ~7% at a 25(OH)D3 concentration of ~120–140 nmol/L. There was a significant degree of tracking for %-C3-epi-25(OH)D3 (correlation coefficient rho between baseline and 1-year values 0.39, P < 0.001). The %-C3-epi-25(OH)D3 level was not related to serum DBP level, DBP phenotype nor to SNPs related to serum 25(OH)D3 level. The serum 25(OH)D3 level could explain less than 3% of %-C3-epi-25(OH)D3 variation. Conclusions: There are considerable individual and reproducible differences in percent C3-epimerization of uncertain clinical importance

Prevalence of vitamin D deficiency and insufficiency among schoolchildren in Greece: The role of sex, degree of urbanisation and seasonality

The current study was aiming to report the prevalence of suboptimal vitamin D status among schoolchildren in Greece and investigate the role of sex, urbanisation and seasonality on vitamin D status. A sample of 2386 schoolchildren (9–13 years old) from four distinct prefectures was examined. The prevalence of 25-hydroxyvitamin D (25(OH)D) concentration <30 and <50 nmol/l (vitamin D deficiency and insufficiency respectively) was 5·2 and 52·5 %, respectively. Girls had a higher prevalence of 25(OH)D<30 (7·2 v. 3·2 %) and 50 nmol/l (57·0 v. 48·0 %) than boys (P<0·001). The highest prevalence rates of 25(OH)D<30 and 50 nmol/l (9·1 and 73·1 %, respectively) were observed during spring (April to June), whereas the lowest (1·5 and 31·9 %, respectively) during autumn (October to December). The prevalence of 25(OH)D<50 nmol/l was higher in urban/semi-urban than rural regions, particularly during spring months (74·6 v. 47·2 %; P<0·001). Female sex, urban/semi-urban region of residence and spring months were found to increase the likelihood of vitamin D deficiency and insufficiency, with the highest OR observed for spring months (7·47; 95 % CI 3·23, 17·3 and 5·14; 95 % CI 3·84, 6·89 for 25(OH)D<30 and 50 nmol/l respectively). In conclusion, despite the southerly latitude, the prevalence of low vitamin D status among primary schoolchildren in Greece is comparable to or exceeds the prevalence reported among children and adolescents on a European level. Sub-populations at highest risk are girls in urban/semi-urban areas during spring months, thus indicating the need for effective initiatives to support adequate vitamin D status in these population groups

A Mediterranean-like dietary pattern with vitamin D3 (10 µg/d) supplements reduced the rate of bone loss in older Europeans with osteoporosis at baseline: results of a 1-y randomized controlled trial

Background: The Mediterranean diet (MD) is widely recommended for the prevention of chronic disease, but evidence for a beneficial effect on bone health is lacking.  Objective: The aim of this study was to examine the effect of a Mediterranean-like dietary pattern [NU-AGE (New Dietary Strategies Addressing the Specific Needs of the Elderly Population for Healthy Aging in Europe)] on indexes of inflammation with a number of secondary endpoints, including bone mineral density (BMD) and biomarkers of bone and collagen degradation in a 1-y multicenter randomized controlled trial (RCT; NU-AGE) in elderly Europeans.  Design: An RCT was undertaken across 5 European centers. Subjects in the intervention group consumed the NU-AGE diet for 1 y by receiving individually tailored dietary advice, coupled with supplies of foods including whole-grain pasta, olive oil, and a vitamin D3 supplement (10 µg/d). Participants in the control group were provided with leaflets on healthy eating available in their country.  Results: A total of 1294 participants (mean ± SD age: 70.9 ±4.0 y; 44% male) were recruited to the study and 1142 completed the 1-y trial. The Mediterranean-like dietary pattern had no effect on BMD (site-specific or whole-body); the inclusion of compliance to the intervention in the statistical model did not change the findings. There was also no effect of the intervention on the urinary biomarkers free pyridinoline or free deoxypyridinoline. Serum 25-hydroxyvitamin D significantly increased and parathyroid hormone decreased (P < 0.001) in the MD compared with the control group. Subgroup analysis of individuals with osteoporosis at baseline (site-specific BMD T-score ≤ −2.5 SDs) showed that the MD attenuated the expected decline in femoral neck BMD (n = 24 and 30 in MD and control groups, respectively; P = 0.04) but had no effect on lumbar spine or whole-body BMD.  Conclusions: A 1-y intervention of the Mediterranean-like diet together with vitamin D3 supplements (10 µg/d) had no effect on BMD in the normal age-related range, but it significantly reduced the rate of loss of bone at the femoral neck in individuals with osteoporosis. The NU-AGE trial is registered at clinicaltrials.gov as NCT01754012

Vitamin D-biofortified beef: a comparison of cholecalciferol with synthetic versus UVB-mushroom-derived ergosterol as feed source

This study investigates dietary fortification of heifer feeds with cholecalciferol and ergocalciferol sources and effects on beef total vitamin D activity, vitamer, respective 25-hydroxymetabolite contents, and meat quality. Thirty heifers were allocated to one of three dietary treatments [(1) basal diet + 4000 IU of vitamin D3 (Vit D3); (2) basal diet + 4000 IU of vitamin D2 (Vit D2); and (3) basal diet + 4000 IU of vitamin D2-enriched mushrooms (Mushroom D2)] for a 30 day pre-slaughter period. Supplementation of heifer diets with Vit D3 yielded higher (p  0.05) by the dietary treatments. In conclusion, vitamin D3 biofortification of cattle diets is the most efficacious way to enhance total beef vitamin D activity

The use of synthetic and natural vitamin D sources in pig diets to improve meat quality and vitamin D content

This study investigated the effects of synthetic and natural sources of vitamin D biofortification in pig diets on pork vitamin D activity and pork quality. One hundred and twenty pigs (60 male, 60 female) were assigned to one of four dietary treatments for a 55 d feeding period. The dietary treatments were (1)50 μg vitamin D₃/kg of feed; (2)50 μg of 25-hydroxvitamin D₃/kg of feed (25-OH-D₃); (3)50 μg vitamin D₂/kg of feed; (4)50 μg vitamin D₂-enriched mushrooms/kg of feed (Mushroom D₂). The pigs offered the 25-OH-D₃ diet exhibited the highest (P < 0.001) serum total 25-hydroxyvitamin D concentration and subsequently exhibited the highest (P < 0.05) Longissimus thoracis (LT) total vitamin D activity. Mushroom D2 and 25-OH-D3 supplementation increased pork antioxidant status. The vitamin D₂-enriched mushrooms improved (P < 0.05) pig performance, carcass weight and LT colour. In conclusion, 25-OH-D₃ is the most successful source for increasing pork vitamin D activity, while Mushroom D2 may be a new avenue to improve animal performance and pork quality

Effect of genetically low 25-hydroxyvitamin D on mortality risk: Mendelian randomization analysis in 3 large European cohorts

Source at https://doi.org/10.3390/nu11010074.The aim of this study was to determine if increased mortality associated with low levels of serum 25-hydroxyvitamin D (25(OH)D) reflects a causal relationship by using a Mendelian randomisation (MR) approach with genetic variants in the vitamin D synthesis pathway. Individual participant data from three European cohorts were harmonized with standardization of 25(OH)D according to the Vitamin D Standardization Program. Most relevant single nucleotide polymorphisms of the genes CYP2R1 (rs12794714, rs10741657) and DHCR7/NADSYN1 (rs12785878, rs11234027), were combined in two allelic scores. Cox proportional hazards regression models were used with the ratio estimator and the delta method for calculating the hazards ratio (HR) and standard error of genetically determined 25(OH)D effect on all-cause mortality. We included 10,501 participants (50.1% females, 67.1±10.1 years) of whom 4003 died during a median follow-up of 10.4 years. The observed adjusted HR for all-cause mortality per decrease in 25(OH)D by 20 nmol/L was 1.20 (95% CI: 1.15–1.25). The HR per 20 nmol/L decrease in genetically determined 25(OH)D was 1.32 (95% CI: 0.80–2.24) and 1.35 (95% CI of 0.81 to 2.37) based on the two scores. In conclusion, the results of this MR study in a combined sample from three European cohort studies provide further support for a causal relationship between vitamin D deficiency and increased all-cause mortality. However, as the current study, even with ~10,000 participants, was underpowered for the study of the effect of the allele score on mortality, larger studies on genetics and mortality are needed to improve the precision

Mobilise-D insights to estimate real-world walking speed in multiple conditions with a wearable device

This study aimed to validate a wearable device’s walking speed estimation pipeline, considering complexity, speed, and walking bout duration. The goal was to provide recommendations on the use of wearable devices for real-world mobility analysis. Participants with Parkinson’s Disease, Multiple Sclerosis, Proximal Femoral Fracture, Chronic Obstructive Pulmonary Disease, Congestive Heart Failure, and healthy older adults (n = 97) were monitored in the laboratory and the real-world (2.5 h), using a lower back wearable device. Two walking speed estimation pipelines were validated across 4408/1298 (2.5 h/laboratory) detected walking bouts, compared to 4620/1365 bouts detected by a multi-sensor reference system. In the laboratory, the mean absolute error (MAE) and mean relative error (MRE) for walking speed estimation ranged from 0.06 to 0.12 m/s and − 2.1 to 14.4%, with ICCs (Intraclass correlation coefficients) between good (0.79) and excellent (0.91). Real-world MAE ranged from 0.09 to 0.13, MARE from 1.3 to 22.7%, with ICCs indicating moderate (0.57) to good (0.88) agreement. Lower errors were observed for cohorts without major gait impairments, less complex tasks, and longer walking bouts. The analytical pipelines demonstrated moderate to good accuracy in estimating walking speed. Accuracy depended on confounding factors, emphasizing the need for robust technical validation before clinical application. Trial registration: ISRCTN – 12246987