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Sample records for 25oh vitamin d2

  1. Case Report: Three Patients With Substantial Serum Levels of 3-Epi-25(OH)D Including One With 3-Epi-25(OH)D2 While on High-Dose Ergocalciferol

    PubMed Central

    Wiebe, Donald

    2014-01-01

    Context: We report the presence of substantial concentrations of 3-epi-25(OH)D3 in two patients and a third patient with 3-epi-25(OH)D2. Patients: The first patient, a 66-year-old female receiving cholecalciferol 4000 IU daily was originally found to have 53 ng/mL of 25(OH)D3 and almost an equal amount of 3-epi-25(OH)D3. Subsequently, the patient had four additional samples, each of which has similar levels of both 25(OH)D3 and 3-epi-25(OH)D3. The second patient, a 7-year-old male receiving cholecalciferol 1000 IU daily, had a 25(OH)D3 concentration of 37 ng/mL and 3-epi-25(OH)D3 of approximately 10 ng/mL. The third and most intriguing patient, a 55-year-old female was receiving ergocalciferol 50 000 IU twice weekly for approximately 3 months, at which time her serum 25(OH)D2 was 64 ng/mL and her 3-epi-25(OH)D2 was approximately 32 ng/mL. This patient's physician changed her vitamin D therapy to cholecalciferol 1000 IU daily, discontinuing ergocalciferol, and a second specimen was collected 5 months later. Analysis of this last specimen found both 25(OH)D3 and 25(OH)D2 at concentrations of 12 and 24 ng/mL respectively, plus corresponding 3-epimer peaks for both 25(OH)D3 and 25(OH)D2 observed chromatographically. Conclusion: The presence of a substantial concentration of 3-epi-25(OH)D in these three patients documents that one cannot assume 3-epi is a trivial metabolite of 25(OH)D for all patients. In addition, the appearance of 3-epi-25(OH)D3 when the last patient changed her vitamin D supplementation from ergocalciferol to cholecalciferol demonstrates that the 3-epimer is probably an endogenous metabolite of 25(OH)D in humans. PMID:24476080

  2. Multicenter Comparison of Seven 25OH Vitamin D Automated Immunoassays

    PubMed Central

    Lippi, Giuseppe; Salvagno, Gian Luca; Fortunato, Antonio; Dipalo, Mariella; Aloe, Rosalia; Da Rin, Giorgio; Giavarina, Davide

    2015-01-01

    Summary Background The measurement of 25OH vitamin D continues to grow in clinical laboratories. The aim of this multi-center study was to compare the results of seven automated commercial immunoassays with a reference HPLC technique. Methods One hundred and twenty consecutive outpatient serum samples were centrifuged, divided in aliquots, frozen and shipped to the participating laboratories. 25OH Vitamin D was measured with a reference HPLC system and with seven automated commercial immunoassays (Roche Cobas E601, Beckman Coulter Unicel DXI 800, Ortho Vitros ES, DiaSorin Liaison, Siemens Advia Centaur, Abbott Architect i System and IDS iSYS). Results Compared to the reference method, the regression coefficients ranged from 0.923 to 0.961 (all p<0.001). The slope of Deming fit ranged from 0.95 to 1.06, whereas the intercept was comprised between −15.2 and 9.2 nmol/L. The bias from the reference HPLC technique varied from −14.5 to 8.7 nmol/L. The minimum performance goal for bias was slightly exceeded by only one immunoassay. The agreement between HPLC and the different immunoassays at 50 nmol/L 25OH Vitamin D varied between 0.61 and 0.85 (all p<0.001). The percentage of samples below this cut-off was significantly different with only one immunoassay. Conclusions The excellent correlation with the reference HPLC technique attests that all seven automated immunoassays may be reliably used for routine assessment of 25OH-D in clinical laboratories. The significant bias among the different methods seems mostly attributable to the lack of standardization and calls for additional efforts for improving harmonization of 25OH-D immunoassays. PMID:28356846

  3. Effect of phototherapy on plasma 25(OH)-vitamin D in neonates.

    PubMed

    Gillies, D R; Hay, A; Sheltawy, M J; Congdon, P J

    1984-01-01

    The possibility that phototherapy may increase plasma levels of 25(OH)-vitamin D was assessed by measuring levels before and after 48 h continuous phototherapy using a standard phototherapy unit (Vickers, Basingstoke , England). There was no significant increase in plasma 25(OH)-vitamin D after 48 h phototherapy and it is concluded that such treatment does not stimulate photobiosynthesis of vitamin D.

  4. Antidepressants differentially related to 1,25-(OH)₂ vitamin D₃ and 25-(OH) vitamin D₃ in late-life depression.

    PubMed

    Oude Voshaar, R C; Derks, W J; Comijs, H C; Schoevers, R A; de Borst, M H; Marijnissen, R M

    2014-04-15

    A low plasma 25-OH vitamin D3 level is a universal risk factor for a wide range of diseases and has also been implicated in late-life depression. It is currently unknown whether the biologically active form of vitamin D, that is, 1,25-(OH)2 vitamin D3, is also decreased in late-life depression, or whether vitamin D levels correlate with specific depression characteristics. We determined plasma 25-OH vitamin D3, 1,25-(OH)2 vitamin D3 and parathormone levels in 355 depressed older persons and 124 non-depressed comparison subjects (age 60 years). Psychopathology was established with the Composite International Diagnostic Interview 2.1, together with potential confounders and depression characteristics (severity, symptom profile, age of onset, recurrence, chronicity and antidepressant drug use). Adjusted for confounders, depressed patients had significantly lower levels of 25-OH vitamin D33 (Cohen's d =0.28 (95% confidence interval: 0.07-0.49), P=0.033) as well as 1,25-(OH)2 vitamin D3 (Cohen's d =0.48 (95% confidence interval: 0.27-0.70), P<0.001) than comparison subjects. Of all depression characteristics tested, only the use of tricyclic antidepressants (TCAs) was significantly correlated with lower 1,25-(OH)2 vitamin D3 levels (Cohen's d =0.86 (95% confidence interval: 0.53-1.19), P<0.001), but not its often measured precursor 25-OH vitamin D3. As vitamin D levels were significantly lower after adjustment for confounders, vitamin D might have an aetiological role in late-life depression. Differences between depressed and non-depressed subjects were largest for the biologically active form of vitamin D. The differential impact of TCAs on 25-OH vitamin D3 and 1,25-(OH)2 vitamin D3 levels suggests modulation of 1-α-hydroxylase and/or 24-hydroxylase, which may in turn have clinical implications for biological ageing mechanisms in late-life depression.

  5. 25(OH)D and 1,25(OH)D vitamin D fails to predict sepsis and mortality in a prospective cohort study

    PubMed Central

    Ratzinger, Franz; Haslacher, Helmuth; Stadlberger, Markus; Schmidt, Ralf L. J.; Obermüller, Markus; Schmetterer, Klaus G.; Perkmann, Thomas; Makristathis, Athanasios; Marculescu, Rodrig; Burgmann, Heinz

    2017-01-01

    The clinical role of vitamin D in sepsis and mortality prediction is controversially discussed. Therefore, we conducted a prospective cohort study on standard care wards, including 461 patients with suspected sepsis fulfilling two or more SIRS criteria. On the first and third day after onset of SIRS symptoms levels of 25(OH)D, 1,25(OH)D and sepsis biomarkers were analysed for their predictive capacity for identifying infection, bacteraemia and an elevated mortality risk. Additionally, several SNPs associated with vitamin D metabolism were evaluated. Bacteraemic patients (28.5%) presented with significantly lower 1,25(OH)D levels than SIRS patients without bacteraemia on the first and third day, while 25(OH)D did not show a predictive capacity. No significant differences of either 1,25(OH)D or 25(OH)D levels were found between SIRS patients with and without infections or between survivors and non-survivors. Sepsis biomarkers, including procalcitonin and CRP, showed a significantly higher discriminatory capacity for these classification tasks. The vitamin D metabolism-related SNPs analysed did not indicate any association with our outcome measures. In conclusion, 1,25(OH)D but not 25(OH)D showed a minor discriminatory value for the prediction of bacteraemia that was inferior to CRP and PCT but both failed to predict sepsis and mortality in a prospective cohort of SIRS patients. PMID:28079172

  6. Vitamin D metabolites in captivity? Should we measure free or total 25(OH)D to assess vitamin D status?

    PubMed

    Bikle, Daniel; Bouillon, Roger; Thadhani, Ravi; Schoenmakers, Inez

    2017-01-16

    There is general consensus that serum 25(OH)D is the best biochemical marker for nutritional vitamin D status. Whether free 25(OH)D would be a better marker than total 25(OH)D is so far unclear. Free 25(OH)D can either be calculated based on the measurement of the serum concentrations of total 25(OH)D, vitamin D-binding protein (DBP), albumin, and the affinity between 25(OH)D and its binding proteins in physiological situations. Free 25(OH)D can also be measured directly by equilibrium dialysis, ultrafitration or immunoassays. During the vitamin D workshop held in Boston in March 2016, a debate was organized about the measurements and clinical value of free 25(OH)D, and this debate is summarized in the present manuscript. Overall there is consensus that most cells apart from the renal tubular cells are exposed to free rather than to total 25(OH)D. Therefore free 25(OH)D may be highly relevant for the local production and action of 1,25(OH)2D. During the debate it became clear that there is a need for standardization of measurements of serum DBP and of direct measurements of free 25(OH)D. There seems to be very limited genetic or racial differences in DBP concentrations or (probably) in the affinity of DBP for its major ligands. Therefore, free 25(OH)D is strongly correlated to total 25(OH)D in most normal populations. Appropriate studies are needed to define the clinical implications of free rather than total 25(OH)D in normal subjects and in disease states. Special attention is needed for such studies in cases of abnormal DBP concentrations or when one could expect changes in its affinity for its ligands.

  7. Free 25(OH)D and the Vitamin D Paradox in African Americans

    PubMed Central

    Mikhail, Mageda; Dhaliwal, Ruban; Shieh, Albert; Usera, Gianina; Stolberg, Alexandra; Ragolia, Louis; Islam, Shahidul

    2015-01-01

    Context: African Americans have a lower total serum 25-hydroxyvitamin D [25(OH)D] but superior bone health. This has been referred to as a paradox. A recent publication found that free serum 25(OH)D is the same in black and white individuals. However, the study was criticized because an indirect method was used to measure free 25(OH)D. A direct method has recently been developed. Objective: We hypothesized that although total serum 25(OH)D is lower in African Americans, free serum 25(OH)D measured directly would not differ between races. Design: White and black healthy postmenopausal women were matched for age and body mass index. Serum total 25(OH)D, PTH, 1,25-dihydroxyvitamin D, vitamin D binding protein (VDBP), and bone density were measured. Measurement of free 25(OH)D was carried out using an ELISA. Setting: The study was conducted at an ambulatory research unit in a teaching hospital. Outcome: A cross-racial comparison of serum free 25(OH)D was performed. Results: A propensity match resulted in the selection of a total of 164 women. Total 25(OH)D was lower in black women (19.5 ± 4.7 vs 26.9 ± 6.4 ng/mL), but a direct measurement of free 25(OH)D revealed almost identical values (5.25 ± 1.2 vs 5.25 ± 1.3 ng/mL) between races. VDBP was significantly lower in blacks when using a monoclonal-based ELISA but higher with a polyclonal-based ELISA. Serum PTH, 1,25-dihydroxyvitamin D, and bone density were higher in African Americans. Conclusions: Free serum 25(OH)D is the same across races despite the lower total serum 25(OH)D in black women. Results comparing VDBP between races using a monoclonal vs a polyclonal assay were discordant. PMID:26161453

  8. Ex vivo culture of primary human colonic tissue for studying transcriptional responses to 1α,25(OH)2 and 25(OH) vitamin D

    PubMed Central

    Mapes, Brandon; Chase, Meredith; Hong, Ellie; Ludvik, Anton; Ceryes, Katy; Huang, Yong

    2014-01-01

    1α,25-Dihydroxyvitamin D3 [1α,25(OH)2D3] is a steroid hormone derived from circulating 25(OH) vitamin D [25(OH)D] with chemopreventive effects in colorectal cancer. 1α,25(OH)2D3 acts through transcriptional mechanisms; however, our understanding of vitamin D transcriptional responses in the colon is derived from studies in transformed cancer cell lines which may not represent responses in normal healthy tissue. Here, we describe the optimization of an ex vivo culture model using primary colonic biopsy samples for studying short-term transcriptional response induced by 1α,25(OH)2D3 and 25(OH)D treatment. Colon biopsy samples from healthy subjects were maintained in primary culture and treated in parallel with 100 nM 1α,25(OH)2D3 or 62.5 nM 25(OH)D and vehicle control (ethanol). Viability was assessed using histology and enzymatic assays. Genome-wide transcriptional responses to 1α,25(OH)2D3 were assessed and expression of 25(OH)D targets CYP27B1 and CYP24A1 were measured by real time PCR. We show that ex vivo culture of colonic tissue remains viable for up to 8 h. The largest number of differentially expressed genes in response to 1α,25(OH)2D3 was noted after 6 h (n = 120). As proof of concept, the top upregulated gene was CYP24A1, a well-established vitamin D-responsive gene. With 25(OH)D treatment, mRNA expression of CYP27B1 was significantly increased after 1 h, while expression of CYP24A1 was greatest at 8 h. Ex vivo culture can be used to assess short-term transcriptional responses to 1α,25(OH)2D3 and 25(OH)D in primary tissue from human colon. Future studies will address interindividual differences in transcriptional responses. PMID:24550213

  9. Cubilin dysfunction causes abnormal metabolism of the steroid hormone 25(OH) vitamin D(3).

    PubMed

    Nykjaer, A; Fyfe, J C; Kozyraki, R; Leheste, J R; Jacobsen, C; Nielsen, M S; Verroust, P J; Aminoff, M; de la Chapelle, A; Moestrup, S K; Ray, R; Gliemann, J; Willnow, T E; Christensen, E I

    2001-11-20

    Steroid hormones are central regulators of a variety of biological processes. According to the free hormone hypothesis, steroids enter target cells by passive diffusion. However, recently we demonstrated that 25(OH) vitamin D(3) complexed to its plasma carrier, the vitamin D-binding protein, enters renal proximal tubules by receptor-mediated endocytosis. Knockout mice lacking the endocytic receptor megalin lose 25(OH) vitamin D(3) in the urine and develop bone disease. Here, we report that cubilin, a membrane-associated protein colocalizing with megalin, facilitates the endocytic process by sequestering steroid-carrier complexes on the cellular surface before megalin-mediated internalization of the cubilin-bound ligand. Dogs with an inherited disorder affecting cubilin biosynthesis exhibit abnormal vitamin D metabolism. Similarly, human patients with mutations causing cubilin dysfunction exhibit urinary excretion of 25(OH) vitamin D(3). This observation identifies spontaneous mutations in an endocytic receptor pathway affecting cellular uptake and metabolism of a steroid hormone.

  10. Low 25 (OH) vitamin D levels are associated with autoimmune thyroid disease in polycystic ovary syndrome.

    PubMed

    Muscogiuri, Giovanna; Palomba, Stefano; Caggiano, Mario; Tafuri, Domenico; Colao, Annamaria; Orio, Francesco

    2016-08-01

    Low 25(OH) vitamin D levels have been associated with several autoimmune diseases and recently with autoimmune thyroid disease (AITD). The aim of the study was to investigate the association of AITD with 25(OH) vitamin D levels in women with polycystic ovary syndrome (PCOS). Fifty women with PCOS were consecutively enrolled and underwent routine health checkups, which included measurements of 25(OH) vitamin D, anti-thyroid peroxidase (TPO-Ab), anti-thyreoglobulin (TG-Ab) antibodies, FT3, FT4, and TSH. Selecting 50 nmol/L as cut-off point, low 25(OH) vitamin D levels were detected in 23 of 50 patients (46 %). AITD was diagnosed when TPO-Ab levels exceeding 80 U/ml and/or TG-Ab levels exceeding 70 U/ml. AITD was detected in 12 of 50 patients (24 %). The levels of 25(OH) vitamin D were significantly lower in women with PCOS and AITD when compared with women with PCOS and without AITD (p = 0.02). In women with AITD no correlation was found between 25(OH) vitamin D and TG-Ab (r = 0.48; p = 0.16), TPO-Ab (r = 0.43; p = 0.21), TSH (r = 0.38; p = 0.27), FT3 (r = -0.40; p = 0.25) and FT4 levels (r = -0.54; p = 0.10). These findings suggest that low levels of 25(OH) vitamin D were significantly associated with AITD in women with PCOS.

  11. 25(OH) vitamin D serum values and rheumatoid arthritis disease activity (DA S28 ESR)

    PubMed Central

    Sahebari, Maryam; Mirfeizi, Zahra; Rezaieyazdi, Zahra; Rafatpanah, Houshang; Goshyeshi, Ladan

    2014-01-01

    Background: The role of vitamin D in the pathogenesis of rheumatoid arthritis is under investigation. This study was designed to evaluate the correlation between serum values of 25(OH) vitamin D [25(OH)D] and disease activity in rheumatoid arthritis (RA) patients according to Disease Activity Score 28 joints and ESR (DA S28 ESR). Methods: Ninety-nine patients according to ACR classification criteria for RA and 68 healthy controls were included in this study. The participants with known confounding risk factors affecting serum values of 25(OH)D were excluded. All patients were under treatment with supplementary calcium carbonate (1500mg), 25(OH)D (800U), and Hydroxychloroquine (6mg/kg). The control group was mostly recruited from patients’ relatives who lived with them to minimize the impact of diverse lifestyles on 25(OH)D status. Disease activity was assessed by DA S28 ESR. Serum concentrations of 25(OH)D were measured. Serum values of 25(OH)D less than 50 nmol/L were considered 25(OH)D deficiency. Results: The mean 25(OH)D serum values were 83.74±46.45 nmol/L in patients and 46.53±34.07 nmol/L in controls. After adjustment for age, sex and BMI, multivariate analysis showed no correlation between 25(OH)D serum levels and DAS in RA (P=0.29, rp=0.11). However, 25(OH)D serum values were significantly lower in patients with early diagnosed RA compared with the other patients (p=0.012). In the early diagnosed patients, 25(OH)D and anti-CCP serum values were negatively correlated (P=0.04, rs=-0.5). Conclusion: This study showed that there was no correlation between 25(OH)D serum values and DAS over a short duration of disease course. However, in early RA, 25(OH) D serum values were lower than the established RA. PMID:25202442

  12. Serum Concentrations of 1,25-Dihydroxyvitamin D2 and 1,25-Dihydroxyvitamin D3 in Response to Vitamin D2 and Vitamin D3 Supplementation

    PubMed Central

    Biancuzzo, Rachael M.; Clarke, Nigel; Reitz, Richard E.; Travison, Thomas G.

    2013-01-01

    Objective: The purpose of this study was to determine 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and 1,25-dihydroxyvitamin D2 [1,25(OH)2D2] levels in healthy adults consuming 1000 IU vitamin D2 or vitamin D3 per day for 11 weeks. Subjects and Design: Blood from 34 healthy male and female adults, aged 18 to 79 years, from a placebo-controlled, double-blind study who received a placebo, 1000 IU vitamin D3, or 1000 IU vitamin D2 daily for 11 weeks at end of winter was analyzed. Serum levels of 25-hydroxyvitamin D2, 25-hydroxyvitamin D3, 1,25(OH)2D2, and 1,25(OH)2D3 were determined by liquid chromatography–tandem mass spectroscopy. Results: Of the adults, 82% were vitamin D insufficient (serum 25-hydroxyvitamin D [25(OH)D <30 ng/mL]) at the start of the study. Administration of vitamin D2 and vitamin D3 induced similar increases in total 25(OH)D as well as in 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3, respectively. Compared with placebo and adjusting for baseline levels, 1000 IU daily of vitamin D2 was associated with a mean increase of 7.4 pg/mL (95% confidence interval, 4.4–10.3) in 1,25(OH)2D2, which was accompanied by a mean decrease of 9.9 pg/mL (−15.8 to −4.0) in 1,25(OH)2D3. No such differences accompanied administration of 1000 IU daily of vitamin D3. Conclusion: Vitamin D2 and vitamin D3 were effective in raising and maintaining total serum concentrations of 25(OH)D. Ingestion of vitamin D2 also resulted in an increase in serum concentrations of 1,25(OH)2D2. This increase was accompanied by a comparable decrease in serum concentrations of 1,25(OH)2D3; therefore, the total 1,25-dihydroxyvitamin D [1,25(OH)2D] concentrations did not significantly change after 11 weeks compared with baseline levels. Ingestion of vitamin D3 did not alter serum concentrations of 1,25(OH)2D3 or total 1,25(OH)2D. Therefore, ingestion of 1000 IU vitamin D2 or vitamin D3 for 11 weeks was effective in raising total serum concentrations of 25(OH)D as well as sustaining serum

  13. Elevated Serum 25(OH)-Vitamin D Levels Are Negatively Correlated with Molar-Incisor Hypomineralization

    PubMed Central

    Thiering, E.; Kratzsch, J.; Heinrich-Weltzien, R.; Hickel, R.; Heinrich, J.; Wichmann, HE; Heinrich, J

    2015-01-01

    To date, the precise etiology of molar-incisor hypomineralization (MIH) is uncertain. Vitamin D plays a key role in hard tissue formation. Therefore, this study aimed to analyze the relationship between serum 25-hydroxy-vitamin D (25(OH)D) status and dental health data obtained from 1,048 children in a 10-year follow-up of the Munich GINIplus and LISAplus birth cohorts. The dental examination included the diagnosis of MIH and recording of (non-)cavitated caries lesions in primary and permanent teeth. Serum 25(OH)D concentrations were taken from blood samples of the 10-year investigation and measured with a fully automated, modular system. Different logistic regression and Poisson hurdle models were calculated. MIH was diagnosed in 13.6% of the study population. Approximately 16.4% of the children demonstrated caries-related defects (D3-4MFS > 0). The mean season-adjusted concentration of 25(OH)D was 75.8 nmol/l (standard deviation 22.0 nmol/l). After adjusting for sex, age, body mass index, parental education, equivalent income, and television/personal computer (TV/PC) viewing hours, a 10 nmol/l increase in serum 25(OH)D concentrations was significantly associated with a lower odds ratio of having MIH (OR = 0.89; P = 0.006). Furthermore, higher 25(OH)D values were associated with a lower number of caries-affected permanent teeth. It is concluded that elevated serum 25(OH)D concentrations were associated with better dental health parameters. PMID:25503610

  14. Elevated serum 25(OH)-vitamin D levels are negatively correlated with molar-incisor hypomineralization.

    PubMed

    Kühnisch, J; Thiering, E; Kratzsch, J; Heinrich-Weltzien, R; Hickel, R; Heinrich, J

    2015-02-01

    To date, the precise etiology of molar-incisor hypomineralization (MIH) is uncertain. Vitamin D plays a key role in hard tissue formation. Therefore, this study aimed to analyze the relationship between serum 25-hydroxy-vitamin D (25(OH)D) status and dental health data obtained from 1,048 children in a 10-year follow-up of the Munich GINIplus and LISAplus birth cohorts. The dental examination included the diagnosis of MIH and recording of (non-)cavitated caries lesions in primary and permanent teeth. Serum 25(OH)D concentrations were taken from blood samples of the 10-year investigation and measured with a fully automated, modular system. Different logistic regression and Poisson hurdle models were calculated. MIH was diagnosed in 13.6% of the study population. Approximately 16.4% of the children demonstrated caries-related defects (D3-4MFS > 0). The mean season-adjusted concentration of 25(OH)D was 75.8 nmol/l (standard deviation 22.0 nmol/l). After adjusting for sex, age, body mass index, parental education, equivalent income, and television/personal computer (TV/PC) viewing hours, a 10 nmol/l increase in serum 25(OH)D concentrations was significantly associated with a lower odds ratio of having MIH (OR = 0.89; P = 0.006). Furthermore, higher 25(OH)D values were associated with a lower number of caries-affected permanent teeth. It is concluded that elevated serum 25(OH)D concentrations were associated with better dental health parameters.

  15. Vitamin D (25(OH)D) in patients with chronic kidney disease stages 2-5

    PubMed Central

    Aguirre Arango, José Vicente

    2016-01-01

    Objective: To establish the impact the chronic kidney disease stage has in the native vitamin D levels in patients not undergoing dialysis treatment. Methods: A study performed in Manizales, Colombia, a city located 2,200 meters above sea level, without important stational variations. Patients with 18 years of age or more, with chronic kidney disease stages 2 to 5 and not undergoing dialysis treatment were recruited for this study. Demographic and anthropometric variations were evaluated as well as solar exposure, CKD etiology and laboratory variables related to bone and mineral diseases. For each CKD clinical stage, correlations were evaluated for vitamin D levels, laboratory results for bone and mineral diseases, solar exposure and ethnicity. Results: Three hundred thirty-three patients were evaluated with a median age of 71 years, most of them mestizo (71%), 173 were women. The main CKD etiology was hypertensive nephropathy (32.2%). 21.1% of patients had normal vitamin D levels, 70.1% were within insufficient range and 8.8% were in deficit. A negative correlation was found between the levels of vitamin 25 (OH) D and the values for: creatinine, phosphorous, calcium x phosphorous product, PTH, 24 hours urine protein and BMI. A positive relationship was found for calcium and albumin. Positive significant statistical correlation was found for vitamin 25(OH) D levels and solar exposure for stages 3b and 4 of CKD. Conclusions: It is common to find low levels of vitamin 25(OH) D in patients with CKD; these can contribute to the appearance of secondary hyperparathyroidism. PMID:27821896

  16. Effect of 24,25-dihydroxyvitamin D3 on 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) metabolism in vitamin D-deficient rats infused with 1,25-(OH)2D3

    SciTech Connect

    Yamato, H.; Matsumoto, T.; Fukumoto, S.; Ikeda, K.; Ishizuka, S.; Ogata, E.

    1989-01-01

    Previous studies revealed that administration of 24,25-dihydroxyvitamin D3 (24,25-(OH)2D3) to calcium (Ca)-deficient rats causes a dose-dependent reduction in markedly elevated serum 1,25-(OH)2D3 level. Although the results suggested that the metabolism of 1,25-(OH)2D3 was accelerated by 24,25-(OH)2D3, those experiments could not define whether the enhanced metabolism of 1,25-(OH)2D3 played a role in the reduction in the serum 1,25-(OH)2D3 level. In the present study, in order to address this issue more specifically, serum 1,25-(OH)2D3 was maintained solely by exogenous administration through miniosmotic pumps of 1,25-(OH)2D3 into vitamin D-deficient rats. Thus, by measuring the serum 1,25-(OH)2D3 concentration, the effect of 24,25-(OH)2D3 on the MCR of 1,25-(OH)2D3 could be examined. Administration of 24,25-(OH)2D3 caused a dose-dependent enhancement in the MCR of 1,25-(OH)2D3, and 1 microgram/100 g rat.day 24,25-(OH)2D3, which elevated serum 24,25-(OH)2D3 to 8.6 +/- 1.3 ng/ml, significantly increased MCR and suppressed serum levels of 1,25-(OH)2D3. The effect of 24,25-(OH)2D3 on 1,25-(OH)2D3 metabolism developed with a rapid time course, and the recovery of iv injected (1 beta-3H)1,25-(OH)2D3 in blood was significantly reduced within 1 h. In addition, there was an increase in radioactivity in the water-soluble fraction of serum as well as in urine, suggesting that 1,25-(OH)2D3 is rapidly degraded to a water-soluble metabolite(s). Furthermore, the reduction in serum 1,25-(OH)2D3 was associated with a reduction in both serum and urinary Ca levels. Because the conversion of (3H)24,25-(OH)2D3 to (3H)1,24,25-(OH)2D3 or other metabolites was minimal in these rats, 24,25-(OH)2D3 appears to act without being converted into other metabolites. These results demonstrate that 24,25-(OH)2D3 rapidly stimulates the metabolism of 1,25-(OH)2D3 and reduces its serum level.

  17. Changes of 25-OH-Vitamin D during Overwintering at the German Antarctic Stations Neumayer II and III

    PubMed Central

    Steinach, Mathias; Kohlberg, Eberhard; Maggioni, Martina Anna; Mendt, Stefan; Opatz, Oliver; Stahn, Alexander; Tiedemann, Josefine; Gunga, Hanns-Christian

    2015-01-01

    Purpose Humans in Antarctica face different environmental challenges, such as low ultra-violet radiation, which is crucial for vitamin D production in humans. Therefore we assessed changes in 25-OH-vitamin D serum concentration during 13 months of overwintering at the German Stations Neumayer II and III (2007–2012). We hypothesized that (i) 25-OH-vitamin D serum concentration would significantly decrease, (ii) changes would be affected by age, gender, baseline (i.e. pre-overwintering) fat mass, baseline 25-OH-vitamin D serum concentration, and station residence, and (iii) our results would not differ from similar previous studies in comparable high latitudes. Materials & Methods 25-OH-vitamin D serum concentrations were determined before, after, and monthly during the campaigns from venous blood samples of n = 43 participants (28 men, 15 women). Baseline fat mass was determined via bio impedance analysis and body plethysmography. Data were analyzed for change over time, dependency on independent parameters, and after categorization for sufficiency (>50nmol/l), insufficiency (25-50nmol/l), and deficiency (<25nmol/l). Results were compared with data from similar previous studies. Results We found a significant decrease of 25-OH-vitamin D with dependency on month. Age, gender, fat mass, and station residence had no influence. Only baseline 25-OH-vitamin D serum concentrations significantly affected subsequent 25-OH-vitamin D values. Conclusions Overwinterings at the Antarctic German research stations Neumayer II and III are associated with a decrease in 25-OH-vitamin D serum concentrations, unaffected by age, gender, baseline fat mass, and station residence. Higher baseline vitamin D serum concentrations might protect from subsequent deficiencies. Residence at the Neumayer Stations may lead to lower vitamin D serum concentrations than found in other comparable high latitudes. PMID:26641669

  18. 25(OH) Vitamin D is Associated with Greater Muscle Strength in Healthy Men and Women

    PubMed Central

    Grimaldi, Adam S.; Parker, Beth A.; Capizzi, Jeffrey A.; Clarkson, Priscilla M.; Pescatello, Linda S.; White, C. Michael; Thompson, Paul D.

    2012-01-01

    Purpose The purpose of the study was to examine the relationship between serum 25-hydroxy vitamin D (25(OH)D) levels and muscle strength in 419 healthy men and women over a broad age range (20-76 years of age). Methods Isometric and isokinetic strength of the arms and legs was measured using computerized dynamometry and its relation to vitamin D was tested in multivariate models controlling for age, gender, resting heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), body mass index (BMI), maximal oxygen uptake (VO2max,), physical activity counts, and season of vitamin D measurement. Results Vitamin D was significantly associated with arm and leg muscle strength when controlling for age and gender. When controlling for other covariates listed above, vitamin D remained directly related to both isometric and isokinetic arm strength but only to isometric leg strength. Conclusion These data suggests that there may be a differential effect of vitamin D on upper and lower body strength. The mechanism for this difference remains unclear but could be related to differences in androgenic effects or to differences in vitamin D receptor expression. Our study supports a direct relationship between vitamin D and muscle strength and suggests that vitamin D supplementation be evaluated to determine if it is an effective therapy to preserve muscle strength in adults. PMID:22895376

  19. Effect of supplementation with vitamin D2-enhanced mushrooms on vitamin D status in healthy adults.

    PubMed

    Stepien, Magdalena; O'Mahony, Louise; O'Sullivan, Aifric; Collier, John; Fraser, William D; Gibney, Michael J; Nugent, Anne P; Brennan, Lorraine

    2013-01-01

    Vitamin D deficiency is emerging worldwide and many studies now suggest its role in the development of several chronic diseases. Due to the low level of vitamin D naturally occurring in food there is a need for supplementation and use of vitamin D-enhanced products. The aim of the present study was to determine if daily consumption of vitamin D2-enhanced mushrooms increased vitamin D status in free-living healthy adults or affected markers of the metabolic syndrome. A total of ninety volunteers (aged 40-65 years) were randomly assigned to one of two 4-week studies: mushroom study (15 µg vitamin D2 or placebo mushroom powder) and capsule study (15 µg vitamin D3 or placebo capsules). Consumption of vitamin D2-enhanced mushrooms increased serum 25-hydroxyvitamin D2 (25(OH)D2) by 128 % from baseline (3·9 (sd 1·9) nmol/l; P < 0·05). Serum 25(OH)D3 increased significantly in the vitamin D3 capsule group (a 55 % increase from a baseline of 44.0 (sd 17·1) nmol/l; P < 0·05). Vitamin D status (25(OH)D) was affected only in the vitamin D3 group. Plasminogen activator inhibitor-1 was lowered by vitamin D2 intake. Vitamin D2 from enhanced mushrooms was bioavailable and increased serum 25(OH)D2 concentration with no significant effect on 25(OH)D3 or total 25(OH)D.

  20. Serum 25(OH) Vitamin D Levels in Polish Women during Pregnancies Complicated by Hypertensive Disorders and Gestational Diabetes

    PubMed Central

    Domaracki, Piotr; Sadlecki, Pawel; Odrowaz-Sypniewska, Grazyna; Dzikowska, Ewa; Walentowicz, Pawel; Siodmiak, Joanna; Grabiec, Marek; Walentowicz-Sadlecka, Malgorzata

    2016-01-01

    Background: An association between the level of vitamin D and the risk of pregnancy-related complications remains unclear. The aim of this study was to examine concentrations of 25(OH) vitamin D in Polish women with normal pregnancies and pregnancies complicated by gestational hypertension, preeclampsia or gestational diabetes mellitus (GDM). Moreover, we analyzed an association between maternal serum 25(OH)D and the risk of gestational hypertension, preeclampsia and GDM. Material and Methods: The study included 207 pregnant women, among them 171 with pregnancy-related complications: gestational hypertension (n = 45), preeclampsia (n = 23) or GDM (n = 103). The control group consisted of 36 women with normal pregnancies. Concentrations of serum 25(OH)D were measured at admission to the hospital prior to delivery Results: Patients with hypertension did not differ significantly from the controls in terms of their serum 25(OH)D concentrations (18.20 vs. 22.10 ng/mL, p = 0.15). Highly significant differences were found in 25(OH)D concentrations of women with preeclampsia and the controls (14.75 vs. 22.10 ng/mL, p = 0.0021). GDM was not associated with significant differences in 25(OH)D concentration. A low level of 25(OH)D turned out to be associated with an increased risk of preeclampsia during pregnancy on both univariate and multivariate regression analysis, and was a significant predictor of this condition on ROC (receiver operating characteristic) analysis (AUC = 0.70, p < 0.01). Conclusions: 25(OH)D deficiency is common among pregnant Polish women. Low concentrations of 25(OH)D may play a role in the etiopathogenesis of preeclampsia. Routine assessment of the 25(OH)D level during pregnancy may be crucial for the identification of women at increased risk of preeclampsia. PMID:27690002

  1. New perspectives on vitamin D food fortification based on a modeling of 25(OH)D concentrations

    PubMed Central

    2013-01-01

    Background In Germany, vitamin D intake from food and synthesis in the skin is low, which leads to low 25(OH)D serum concentrations. In contrast to many other countries, general vitamin D food fortification is still prohibited in Germany, although the European Commission published a regulatory framework to harmonize addition of vitamins to foods. Thus the purpose of our study was to develop a vitamin D fortification model, taking into account all vitamin D sources with the goal to fulfill requirements of intake recommendations or preferable 25(OH)D serum concentrations. Finally, the aim was to assess the suitability of different carriers and associated risks. Methods We developed a mathematical bottom-up model of 25(OH)D serum concentrations based on data about vitamin D sources of the German population such as sunlight, food and supplements for all federal states taking seasonal and geographical variations into account. We used this model to calculate the optimal fortification levels of different vitamin D carriers in two approaches. First we calculated required fortification levels based on fixed intake recommendations from e.g. the IOM or the DGE and second based on achieving certain 25(OH)D serum concentrations. Results To lift 25(OH)D serum concentration in Germany to 75 nmol/L, e.g. 100 g bread has to be fortified with 11.3 μg during winter, resulting in a daily vitamin D intake of 23.7 μg. Bread seems to be a suitable carrier for base supply. However, overdose risk with a single fortified product is higher than the risk with several fortified carriers. Conclusions With the model in hand, it is possible to conceive vitamin D fortification strategies for different foodstuffs and model its impact on 25(OH)D serum concentrations. PMID:24261676

  2. Serum 25-OH vitamin D levels in systemic sclerosis: analysis of 140 patients and review of the literature.

    PubMed

    Giuggioli, Dilia; Colaci, M; Cassone, G; Fallahi, P; Lumetti, F; Spinella, A; Campomori, F; Manfredi, A; Manzini, C U; Antonelli, A; Ferri, C

    2017-03-01

    Hypovitaminosis D is increasingly reported in autoimmune diseases. We investigated the 25-OH-vitamin D (25-OH-vitD) levels in systemic sclerosis (SSc) patients, in correlation with disease's features. We measured the 25-OH-vitD serum levels in 140 consecutive patients (F/M 126/15; mean age 61 ± 15.1 years), 91 without (group A) and 49 with (group B) 25-OH-cholecalciferol supplementation. Patients of group A invariably showed low 25-OH-vitD levels (9.8 ± 4.1 ng/ml vs. 26 ± 8.1 ng/ml of group B); in particular, 88/91 (97%) patients showed vitamin D deficiency (<20 ng/ml), with very low vitamin D levels (<10 ng/ml) in 40 (44%) subjects. Only 15/49 (30.6%) patients of group B reached normal levels of 25-OH-vitD (≥30 ng/ml), whereas vitamin D deficiency persisted in 12/49 (24.5%) individuals. Parathormone levels inversely correlated with 25-OH-vitD (r = -0.3, p < 0.0001). Of interest, hypovitaminosis D was statistically associated with autoimmune thyroiditis (p = 0.008), while calcinosis was more frequently observed in patients of group A (p = 0.057). Moreover, we found significantly higher percentage of serum anticentromere antibodies in group B patients with 25-OH-vitD level ≥30 ng/ml (8/15 vs. 6/34; p = 0.017). In literature, hypovitaminosis D is very frequent in SSc patients. An association with disease duration, calcinosis, or severity of pulmonary involvement was occasionally recognized. Hypovitaminosis D is very frequent in SSc and severe in a relevant percentage of patients; furthermore, less than one third of supplemented subjects reached normal levels of 25-OH-vitD. The evaluation of 25-OH-vitD levels should be included in the routine clinical work-up of SSc. The above findings expand previous observations and may stimulate further investigations.

  3. Induction of CFTR gene expression by 1,25(OH)2 vitamin D3, 25OH vitamin D3, and vitamin D3 in cultured human airway epithelial cells and in mouse airways.

    PubMed

    DiFranco, Kristina M; Mulligan, Jennifer K; Sumal, Aman S; Diamond, Gill

    2017-01-24

    Cystic fibrosis (CF) is an autosomal recessive disorder caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which often leads to protein misfolding and no CFTR surface localization. This then leads to chronic airway infections, inflammation, and tissue damage. Although vitamin D has been explored as a therapy to treat CF due to its antimicrobial-inducing and anti-inflammatory properties, the effect of 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3) on CFTR directly has not been studied. We treated cultured healthy and diseased bronchial epithelial cells (BEC) with 10nM 1α,25(OH)2D3 for 6 and 24h and found that 1α,25(OH)2D3 increases both mRNA and protein CFTR levels using RT-qPCR, flow cytometry and fluorescence immunohistochemistry. Treatment of CF cells with 10nM 1α,25(OH)2D3 led to an increase in both total and surface CFTR expression, suggesting 1α,25(OH)2D3 could be used to increase properly localized CFTR in airway cells. To determine if BEC could convert the more clinically relevant cholecalciferol to 25OHD3, cultured non-CF and CF BECs were treated with a range of cholecalciferol concentrations, and 25OHD3 levels were quantified by ELISA. We found that 25OHD3 levels increased in a concentration-dependent manner. Treatment of BEC with 10μM cholecalciferol led to increases in both CYP24A1 and CFTR mRNA levels, even when added to the apical surface of cells grown in an air-liquid interface, suggesting that topical administration of vitamin D could be used therapeutically. To demonstrate this in vivo, we intranasally delivered 1μM 1α,25(OH)2D3 into mice. After 6h, we observed induction of both Cyp24A1 and CFTR expression in the tracheas of treated mice. The major findings of this study are that vitamin D can be converted to the active form when topically administered to the airway, and this could be used to increase CFTR levels in patients with CF. This could potentially be useful as an adjunctive therapy, together with

  4. Vitamin D, serum 25(OH)D, LL-37 and polymorphisms in a Canadian First Nation population with endemic tuberculosis

    PubMed Central

    Larcombe, Linda; Mookherjee, Neeloffer; Slater, Joyce; Slivinski, Caroline; Dantouze, Joe; Singer, Matthew; Whaley, Chris; Denechezhe, Lizette; Matyas, Sara; Decter, Kate; Turner-Brannen, Emily; Ramsey, Clare; Nickerson, Peter; Orr, Pamela

    2015-01-01

    Background Canadian First Nation populations have experienced endemic and epidemic tuberculosis (TB) for decades. Vitamin D–mediated induction of the host defence peptide LL-37 is known to enhance control of pathogens such as Mycobacterium tuberculosis. Objective Evaluate associations between serum levels of 25-hydroxy vitamin D (25(OH)D) and LL-37, in adult Dene First Nation participants (N = 34) and assess correlations with single nucleotide polymorphisms (SNPs) in the vitamin D receptor (VDR) and vitamin D binding protein (VDBP). Design Venous blood was collected from all participants at baseline (winter and summer) and in conjunction with taking vitamin D supplements (1,000 IU/day) (winter and summer). Samples were analysed using ELISA for concentrations of vitamin D and LL-37, and SNPs in the VDR and VDBP regions were genotyped. Results Circulating levels of 25(OH)D were not altered by vitamin D supplementation, but LL-37 levels were significantly decreased. VDBP and VDR SNPs did not correlate with serum concentrations of 25(OH)D, but LL-37 levels significantly decreased in individuals with VDBP D432E T/G and T/T, and with VDR SNP Bsm1 T/T genotypes. Conclusions Our findings suggest that vitamin D supplementation may not be beneficial as an intervention to boost innate immune resistance to M. tuberculosis in the Dene population. PMID:26294193

  5. Sequential hydroxylation of vitamin D2 by a genetically engineered CYP105A1.

    PubMed

    Hayashi, Keiko; Yasuda, Kaori; Yogo, Yuya; Takita, Teisuke; Yasukawa, Kiyoshi; Ohta, Miho; Kamakura, Masaki; Ikushiro, Shinichi; Sakaki, Toshiyuki

    2016-05-13

    Our previous studies revealed that the double variants of CYP105A1- R73A/R84A and R73V/R84A-show high levels of activity with respect to conversion of vitamin D3 to its biologically active form, 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3). In this study, we found that both the double variants were also capable of converting vitamin D2 to its active form, that is, 1α,25-dihydroxyvitamin D2 (1α,25(OH)2D2), via 25(OH)D2, whereas its 1α-hydroxylation activity toward 25(OH)D2 was much lower than that toward 25(OH)D3. Comparison of the wild type and the double variants revealed that the amino acid substitutions remarkably enhanced both 25- and 26-hydroxylation activity toward vitamin D2. After 25-hydroxylation of vitamin D2, further hydroxylation at C26 may occur frequently without the release of 25(OH)D2 from the substrate-binding pocket. Thus, the double variants of CYP105A1 are quite useful to produce 25,26(OH)2D2 that is one of the metabolites of vitamin D2 detected in human serum.

  6. Seasonal variations of 25-OH vitamin D serum levels are associated with clinical disease activity in multiple sclerosis patients.

    PubMed

    Hartl, Christina; Obermeier, Viola; Gerdes, Lisa Ann; Brügel, Mathias; von Kries, Rüdiger; Kümpfel, Tania

    2017-04-15

    Low 25-hydroxy vitamin D (25-[OH]-D) serum concentrations have been associated with higher disease activity in multiple sclerosis (MS) patients. In a large cross-sectional study we assessed the vitamin D status in MS patients in relation to seasonality and relapse rate. 415 MS-patients (355 relapsing-remitting MS and 60 secondary-progressive, 282 female, mean age 39.1years) of whom 25-(OH)-D serum concentrations were determined at visits between 2010 and 2013 were included in the study. All clinical data including relapse at visit and expanded disability status scale were recorded in a standardized manner by an experienced neurologist. Seasonal variations of 25-(OH)-D serum concentrations were modelled by sinusoidal regression and seasonal variability in the prevalence of relapse by cubic regression. The mean 25-(OH)-D serum concentration was 24.8ng/ml (range 8.3-140ng/ml) with peak levels of 32.2ng/ml in July/August and nadir in January/February (17.2ng/ml). The lowest modelled prevalence of relapse was in September/October (28%) and the highest modelled prevalence in March/April (47%). The nadir of 25-(OH)-D serum concentrations preceded the peak in prevalence of relapses by two months. In summary, seasonal variation of 25-(OH)-D serum levels were inversely associated with clinical disease activity in MS patients. Future studies should investigate whether vitamin D supplementation in MS patients may decrease the seasonal risk for MS relapses.

  7. Vitamin D-binding protein, vitamin D status and serum bioavailable 25(OH)D of young Asian Indian males working in outdoor and indoor environments.

    PubMed

    Goswami, Ravinder; Saha, Soma; Sreenivas, Vishnubhatla; Singh, Namrata; Lakshmy, Ramakrishnan

    2017-03-01

    Urban Asian Indians generally have low serum 25(OH)D. Information on serum bioavailable 25(OH)D and the effect of prolonged sun-exposure in them is not known. We assessed serum 25(OH)D and bioavailable 25(OH)D in males with varying durations of sun-exposure in Delhi during August-September. Serum 25(OH)D, vitamin D-binding protein (DBP), bioavailable 25(OH)D, free 25(OH)D index, iPTH, ionized calcium and sun-index were assessed in outdoor, mixed outdoor-indoor and indoor workers (n = 88, 32 and 74, respectively). The mean sun-index (12.0 ± 6.25, 4.3 ± 2.20 and 0.7 ± 0.62, respectively; P < 0.001) was highest outdoors and lowest indoors. Serum 25(OH)D (29.0 ± 8.61, 19.1 ± 5.73 and 10.9 ± 4.19 ng/ml, respectively; P < 0.001), bioavailable 25(OH)D and free 25(OH)D index were maximum in outdoor workers followed by mixed-exposure and indoor workers. Their mean serum DBP levels (241.2 ± 88.77, 239.3 ± 83.40 and 216.6 ± 63.93 µg/ml, respectively; P = 0.12) were comparable. Mean serum iPTH was significantly lower in outdoor than indoor workers and showed inverse correlations with serum 25(OH)D, bioavailable 25(OH)D and free 25(OH)D index (r = -0.401, -0.269 and -0.236, respectively; P < 0.001 in all). Daily dietary-calorie intake was higher and calcium lower in outdoor than indoor workers. On regression analysis, sun-exposure was the only significant variable, increasing serum 25(OH)D by 2.03 ng/ml per hour of sun-exposure (95 % confidence interval 1.77-2.28; P < 0.001). Outdoor workers with prolonged sun-exposure were vitamin D-sufficient, with higher serum bioavailable 25(OH)D than the indoor workers during summer. Use of serum DBP levels did not affect the interpretation of their vitamin D status.

  8. Colonic transcriptional response to 1α,25(OH)2 vitamin D3 in African- and European-Americans.

    PubMed

    Alleyne, Dereck; Witonsky, David B; Mapes, Brandon; Nakagome, Shigeki; Sommars, Meredith; Hong, Ellie; Muckala, Katy A; Di Rienzo, Anna; Kupfer, Sonia S

    2017-04-01

    Colorectal cancer (CRC) is a significant health burden especially among African Americans (AA). Epidemiological studies have correlated low serum vitamin D with CRC risk, and, while hypovitaminosis D is more common and more severe in AA, the mechanisms by which vitamin D modulates CRC risk and how these differ by race are not well understood. Active vitamin D (1α,25(OH)2D3) has chemoprotective effects primarily through transcriptional regulation of target genes in the colon. We hypothesized that transcriptional response to 1α,25(OH)2D3 differs between AA and European Americans (EA) irrespective of serum vitamin D and that regulatory variants could impact transcriptional response. We treated ex vivo colon cultures from 34 healthy subjects (16 AA and 18 EA) with 0.1μM 1α,25(OH)2D3 or vehicle control for 6h and performed genome-wide transcriptional profiling. We found 8 genes with significant differences in transcriptional response to 1α,25(OH)2D3 between AA and EA with definitive replication of inter-ethnic differences for uridine phosphorylase 1 (UPP1) and zinc finger-SWIM containing 4 (ZSWIM4). We performed expression quantitative trait loci (eQTL) mapping and identified response cis-eQTLs for ZSWIM4 as well as for histone deacetylase 3 (HDAC3), the latter of which showed a trend toward significant inter-ethnic differences in transcriptional response. Allele frequency differences of eQTLs for ZSWIM4 and HDAC3 accounted for observed transcriptional differences between populations. Taken together, our results demonstrate that transcriptional response to 1α,25(OH)2D3 differs between AA and EA independent of serum 25(OH)D levels. We provide evidence in support of a genetic regulatory mechanism underlying transcriptional differences between populations for ZSWIM4 and HDAC3. Further work is needed to elucidate how response eQTLs modify vitamin D response and whether genotype and/or transcriptional response correlate with chemopreventive effects. Relevant biomarkers

  9. The Effect of the Systemic Inflammatory Response on Plasma Vitamin 25 (OH) D Concentrations Adjusted for Albumin

    PubMed Central

    Ghashut, Rawia A.; Talwar, Dinesh; Kinsella, John; Duncan, Andrew; McMillan, Donald C.

    2014-01-01

    Background Plasma 25-hydroxyvitamin D (25(OH) D) deficiencies are associated with several diseases. The magnitude of systemic inflammatory response, as evidenced by C-reactive protein (CRP), is a major factor associated with lower 25(OH)D. Other aspects of the systemic inflammatory response may be important in determining plasma 25 (OH)D concentrations. Aim To examine the relationship between plasma 25(OH)D, CRP and albumin concentrations in two patient cohorts. Methods 5327 patients referred for nutritional assessment and 117 patients with critical illness were examined. Plasma 25 (OH) D concentrations were measured using standard methods. Intra and between assay imprecision was <10%. Result In the large cohort, plasma 25 (OH) D was significantly associated with CRP (rs = −0.113, p<0.001) and albumin (rs = 0.192, p<0.001). 3711 patients had CRP concentrations ≤10 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were significantly lower from 35 to 28 to 14 nmol/l (p<0.001). This decrease was significant when albumin concentrations were reduced between 25–34 g/L (p<0.001) and when albumin <25 g/L (p<0.001). 1271 patients had CRP concentrations between 11–80 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were significantly lower from 31 to 24 to 19 nmol/l (p<0.001). This decrease was significant when albumin concentration were 25–34 g/L (p<0.001) and when albumin <25 g/L (p<0.001). 345 patients had CRP concentrations >80 mg/L; with decreasing albumin concentrations ≥35, 25–34 and <25 g/l, median concentrations of 25 (OH) D were not significantly altered varying from 19 to 23 to 23 nmol/l. Similar relationships were also obtained in the cohort of patients with critical illness. Conclusion Plasma concentrations of 25(OH) D were independently associated with both CRP and albumin and consistent with the systemic inflammatory

  10. Association between Parathyroid Hormone, 25 (OH) Vitamin D, and Chronic Kidney Disease: A Population-Based Study

    PubMed Central

    Wang, Wei-Hao; Chen, Li-Wei; Sun, Chiao-Yin; Hsu, Heng-Rong; Chien, Rong-Nang

    2017-01-01

    Identification of the accurate risk factor for CKD remains mandatory to combat the high prevalence of diseases. Growing evidence suggests the association of serum vitamin D with diverse health conditions. However, the relationship between vitamin D, intact parathyroid hormone (PTH), and calcium-phosphate metabolism and development of CKD remains controversial. We conduct this cross-sectional observational study to investigate the association between serum 25 (OH) vitamin D, intact PTH, and calcium and phosphate levels with eGFR and albuminuria, as a surrogate marker of CKD, in a community population. A total of 4080 participants were recruited. The mean age was 58.4 ± 13.3 years and 1480 (36.3%) were men. The mean eGFR was 94.1 ± 26.3 mL/min/1.73 m2. The prevalence of CKD was 19.8%. Serum 25 (OH) vitamin D and log intact PTH levels were inversely correlated with eGFR but positively correlated with log albuminuria. Logistic regression analysis identified the log intact PTH as an independent factor associated with eGFR ≤ 60 mL/min/1.73 m2 and proteinuria. This association was consistent when serum intact PTH was analyzed as continuous as well as categorical variables (as hyperparathyroidism). The relationship remains significant using resampling subset analysis with comparable baseline characteristics and adjustment for 25 (OH) vitamin D, calcium, and phosphate levels. This finding warranted further research to clarify the causal relationship of PTH/25 (OH) vitamin D with the risk of CKD in the general population. PMID:28367447

  11. Low 25(OH) Vitamin D3 Levels Are Associated with Adverse Outcome in Newly-Diagnosed Intensively-Treated Adult Acute Myeloid Leukemia Patients

    PubMed Central

    Lee, Hun Ju; Muindi, Josephia R.; Tan, Wei; Hu, Qiang; Wang, Dan; Liu, Song; Wilding, Gregory E.; Ford, Laurie A.; Sait, Sheila N.J.; Block, Annemarie W.; Adjei, Araba A.; Barcos, Maurice; Griffiths, Elizabeth A; Thompson, James E.; Wang, Eunice S.; Johnson, Candace S; Trump, Donald L.; Wetzler, Meir

    2013-01-01

    Background Several studies suggest that low 25(OH) vitamin D3 levels may be prognostic in some malignancies, but no studies have evaluated their impact on treatment outcome in acute myeloid leukemia (AML). Methods VD levels were evaluated in 97 consecutive newly diagnosed, intensively-treated AML patients. MicroRNA-expression profiles and single nucleotide polymorphisms (SNPs) in the 25(OH) vitamin D3 pathway genes were evaluated and correlated with 25(OH) vitamin D3 levels and treatment outcome. Results Thirty-four (35%) patients had normal 25(OH) vitamin D3 levels (32–100 ng/ml), 34 (35%) insufficient (20–31.9 ng/ml) and 29 (30%) deficient levels (<20 ng/ml). Insufficient/deficient 25(OH) vitamin D3 levels were associated with worse relapse-free survival (RFS) compared to normal vitamin D3 levels. In multivariate analyses, deficient 25(OH) vitamin D3, smoking, European LeukemiaNet Genetic Groups and white blood cell count retained their statistical significance for RFS. A number of microRNAs and SNPs were found to be associated with 25(OH) vitamin D3 level, although none remained significant after multiple test corrections; one 25(OH) vitamin D3 receptor SNP, rs10783219, was associated with lower complete remission rate (p=0.0442), shorter RFS (p=0.0058) and overall survival (p=0.0011). Conclusions It remains to be determined what role microRNA and SNP profiles play in contributing to low 25(OH) vitamin D3 level and/or outcome and whether supplementation will improve AML outcome. PMID:24166051

  12. Effects of vitamin D2-fortified bread v. supplementation with vitamin D2 or D3 on serum 25-hydroxyvitamin D metabolites: an 8-week randomised-controlled trial in young adult Finnish women.

    PubMed

    Itkonen, Suvi T; Skaffari, Essi; Saaristo, Pilvi; Saarnio, Elisa M; Erkkola, Maijaliisa; Jakobsen, Jette; Cashman, Kevin D; Lamberg-Allardt, Christel

    2016-04-14

    There is a need for food-based solutions for preventing vitamin D deficiency. Vitamin D3 (D3) is mainly used in fortified food products, although the production of vitamin D2 (D2) is more cost-effective, and thus may hold opportunities. We investigated the bioavailability of D2 from UV-irradiated yeast present in bread in an 8-week randomised-controlled trial in healthy 20-37-year-old women (n 33) in Helsinki (60°N) during winter (February-April) 2014. Four study groups were given different study products (placebo pill and regular bread=0 µg D2 or D3/d; D2 supplement and regular bread=25 µg D2/d; D3 supplement and regular bread=25 µg D3/d; and placebo pill and D2-biofortified bread=25 µg D2/d). Serum 25-hydroxyvitamin D2 (S-25(OH)D2) and serum 25-hydroxyvitamin D3 (S-25(OH)D3) concentrations were measured at baseline, midpoint and end point. The mean baseline total serum 25-hydroxyvitamin D (S-25(OH)D=S-25(OH)D2+S-25(OH)D3) concentration was 65·1 nmol/l. In repeated-measures ANCOVA (adjusted for baseline S-25(OH)D as total/D2/D3), D2-bread did not affect total S-25(OH)D (P=0·707) or S-25(OH)D3 (P=0·490), but increased S-25(OH)D2 compared with placebo (P<0·001). However, the D2 supplement was more effective than bread in increasing S-25(OH)D2 (P<0·001). Both D2 and D3 supplementation increased total S-25(OH)D compared with placebo (P=0·030 and P=0·001, respectively), but D2 supplementation resulted in lower S-25(OH)D3 (P<0·001). Thus, D2 from UV-irradiated yeast in bread was not bioavailable in humans. Our results support the evidence that D2 is less potent in increasing total S-25(OH)D concentrations than D3, also indicating a decrease in the percentage contribution of S-25(OH)D3 to the total vitamin D pool.

  13. Cestrum diurnum leaf as a source of 1,25(OH)2 Vitamin D3 improves egg shell thickness.

    PubMed

    Chennaiah, S; Qadri, S S Y H; Rao, S V Rama; Shyamsunder, G; Raghuramulu, N

    2004-05-01

    A continuing concern of the poultry industry is the high incidence (12%) of egg losses in the laying house due to poor egg shell quality. Calcium (Ca) homeostasis is a key factor in egg shell formation. The economy of Ca utilisation is under the control of Vitamin D(3), particularly its active metabolite 1,25-dihydroxy cholecalciferol [1,25(OH)(2)D(3)]. Supplementation of 1,25(OH)(2)D(3) has been shown to increase specific gravity, shell thickness and shell weight of the egg. However, commercially available synthetic 1,25(OH)(2)D(3) is very expensive. Earlier studies from our Institute [Phytochemistry 37 (1994) 677] have identified a cheap, natural and rich source of 1,25(OH)(2)D(3) in the leaves of Cestrum diurnum (CD), a member of the Solanaceae family. In this study, CD leaves were explored as a source of 1,25(OH)(2)D(3) in the feed of layer birds to improve the egg shell thickness. Fifteen-week-old white leghorn layers were divided into four treatments of 60 birds each and as follows: (I) normal diet with Vitamin D(3), (II) normal diet with Vitamin D(3) + CD, (III) normal diet without Vitamin D(3) and, (IV) normal diet without Vitamin D(3) + CD powder. CD leaf powder was incorporated in to the feed at 0.3% level. The experimental feeding was continued up to 72 weeks of age of the birds. Weekly food intake and daily egg production were noted throughout the experimental period and the specific gravity of the eggs, feed consumed to lay one egg and egg shell thickness were determined. Incorporation of CD leaves in the feed had the maximal effect on all the parameters studied. The feed consumed to lay one egg was 20 g less than the control group. The specific gravity of the egg was higher by 0.005, than the control egg, indicating a 5% decrease in the breakage of eggs in CD fed chicks. Also there was a significant increase (P < 0.001) in egg shell thickness. The data suggest that incorporation of CD leaf powder in the feed of poultry layers increased the egg shell

  14. Interlaboratory trial for measurement of vitamin D and 25(OH)D in foods and a dietary supplement using liquid chromatography-mass spectrometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Assessment of total vitamin D intake from foods and dietary supplements (DSs) may be incomplete if 25-hydroxyvitamin D [25(OH)D] intake is not included. However, 25(OH)D data for such intake assessments are lacking, no food or DS reference materials (RMs) are available, and comparison of laboratory...

  15. Comparison of metabolism of vitamins D2 and D3 in children with nutritional rickets.

    PubMed

    Thacher, Tom D; Fischer, Philip R; Obadofin, Michael O; Levine, Michael A; Singh, Ravinder J; Pettifor, John M

    2010-09-01

    Children with calcium-deficiency rickets may have increased vitamin D requirements and respond differently to vitamin D(2) and vitamin D(3). Our objective was to compare the metabolism of vitamins D(2) and D(3) in rachitic and control children. We administered an oral single dose of vitamin D(2) or D(3) of 1.25 mg to 49 Nigerian children--28 with active rickets and 21 healthy controls. The primary outcome measure was the incremental change in vitamin D metabolites. Baseline serum 25-hydroxyvitamin D [25(OH)D] concentrations ranged from 7 to 24 and 15 to 34 ng/mL in rachitic and control children, respectively (p < .001), whereas baseline 1,25-dihydroxyvitamin D [1,25(OH)(2)D] values (mean ± SD) were 224 ± 72 and 121 ± 34 pg/mL, respectively (p < .001), and baseline 24,25-dihydroxyvitamin D [24,25(OH)(2)D] values were 1.13 ± 0.59 and 4.03 ± 1.33 ng/mL, respectively (p < .001). The peak increment in 25(OH)D was on day 3 and was similar with vitamins D(2) and D(3) in children with rickets (29 ± 17 and 25 ± 11 ng/mL, respectively) and in control children (33 ± 13 and 31 ± 16 ng/mL, respectively). 1,25(OH)(2)D rose significantly (p < .001) and similarly (p = .18) on day 3 by 166 ± 80 and 209 ± 83 pg/mL after vitamin D(2) and D(3) administration, respectively, in children with rickets. By contrast, control children had no significant increase in 1,25(OH)(2)D (19 ± 28 and 16 ± 38 pg/mL after vitamin D(2) and D(3) administration, respectively). We conclude that in the short term, vitamins D(2) and D(3) similarly increase serum 25(OH)D concentrations in rachitic and healthy children. A marked increase in 1,25(OH)(2)D in response to vitamin D distinguishes children with putative dietary calcium-deficiency rickets from healthy children, consistent with increased vitamin D requirements in children with calcium-deficiency rickets. © 2010 American Society for Bone and Mineral

  16. Vitamin D receptor gene polymorphisms/haplotypes and serum 25(OH)D3 levels in Hashimoto's thyroiditis.

    PubMed

    Giovinazzo, Salvatore; Vicchio, Teresa M; Certo, Rosaria; Alibrandi, Angela; Palmieri, Orazio; Campennì, Alfredo; Cannavò, Salvatore; Trimarchi, Francesco; Ruggeri, Rosaria Maddalena

    2017-02-01

    Vitamin D deficiency and/or reduced function, as per certain polymorphisms of the vitamin D receptor (VDR) gene, have been related to several autoimmune disorders. The present study was aimed to investigate the association of Hashimoto's thyroiditis with vitamin D status and functional polymorphisms (SNPs) of the VDR gene. In this case-control study, 200 euthyroid subjects were enrolled: 100 newly diagnosed HT patients (87 F, 13 M; mean age ± SD 42 ± 15 year) and 100 healthy individuals, matched for age, sex, BMI, and month of blood sampling. Serum 25(OH)D3 was measured by HPLC. The VDR SNPs BsmI, ApaI, and TaqI, in strong linkage disequilibrium with each other, were detected by restriction fragment length polymorphism-PCR. The prevalence of vitamin D deficiency in HT patients was significantly higher than that in the control group (70 vs 18.2 %; p < 0.0001), and median serum 25(OH)D3 level was significantly lower in HT patients than controls (median value: 16.2 vs 37.4 ng/ml; p = 0.026). Moreover, there was a significant inverse correlation between serum 25(OH)D3 and TPOAb concentration (r = -0.669; p = 0.034). Contrarily, the genotype distribution of the studied SNPs was not different in the two groups (BsmI p = 0.783; ApaI p = 0.512; TaqI p = 0.471), as was the allelic frequency [f(B) p = 0.776, f(b) p = 0.887; f(A) p = 0.999, f(a) p = 0.999; f(T) p = 0.617; f(t) p = 0.617]. The present study first investigates newly diagnosed untreated HT and suggests that vitamin D deficiency may contribute to HT development and/or progression, acting as an environmental trigger, while the VDR locus does not appear to be involved in conditioning the genetic susceptibility to the disease, at least in Caucasians.

  17. 25 (OH) Vitamin D Levels and Renal Disease Progression in Patients with Type 2 Diabetic Nephropathy and Blockade of the Renin-Angiotensin System

    PubMed Central

    Luño, José; Barrio, Vicente; de Vinuesa, Soledad García; Praga, Manuel; Goicoechea, Marian; Lahera, Vicente; Casas, Luisa; Oliva, Jesús

    2013-01-01

    Summary Background and objectives Experimental studies show that 25 (OH) vitamin D is a suppressor of renin biosynthesis and that vitamin D deficiency has been associated with CKD progression. Patients with type II diabetes and CKD have an exceptionally high rate of severe 25 (OH) vitamin D deficiency; however, it is not known whether this deficiency is a risk factor for progression of diabetic nephropathy. This study aimed to investigate whether there is an association of 25 (OH) vitamin D deficiency with disease progression in type II diabetic nephropathy. Design, setting, participants, & measurements 25 (OH) vitamin D levels were measured at baseline and 4 and 12 months in 103 patients included in a multicenter randomized controlled trial to compare the efficacy of combining an angiotensin-converting enzyme inhibitor and an angiotensin receptor blocker with the efficacy of each drug in monotherapy to slow progression of established diabetic nephropathy during 2006–2011. The primary composite endpoint was a >50% increase in baseline serum creatinine, ESRD, or death. All study participants were included in the analysis. Results Fifty-three patients (51.5%) had 25 (OH) vitamin D deficiency (<15 ng/ml). After a median follow-up of 32 months, the endpoint was reached by 23 patients with deficiency (43.4%) and 8 patients without (16%). Multivariate Cox regression analysis adjusted for urinary protein/creatinine ratio, estimated GFR, and baseline aldosterone showed that 25 (OH) vitamin D deficiency was associated with the primary endpoint (hazard ratio, 2.88; 95% confidence interval, 1.84 to 7.67; P=0.04). Conclusions These results show that 25 (OH) vitamin D deficiency is independently associated with a higher risk of the composite outcome in patients with type II diabetic nephropathy. PMID:24135218

  18. Pharmacokinetics and effects of demographic factors on blood 25(OH)D3 levels after a single orally administered high dose of vitamin D3

    PubMed Central

    Chen, Pei-zhan; Li, Mian; Duan, Xiao-hua; Jia, Jing-ying; Li, Jing-quan; Chu, Rui-ai; Yu, Chen; Han, Jun-hua; Wang, Hui

    2016-01-01

    Aim: To examine the biological consequences and demographic factors that might affect the pharmacokinetics of vitamin D3 after a single high dose intervention in a young Chinese population with vitamin D insufficiency status. Methods: A total of 28 young subjects (25 to 35 years old) with vitamin D insufficiency status [serum 25(OH)D <30 ng/mL] was recruited in Shanghai, China. The subjects were orally administered a single high dose of vitamin D3 (300 000 IU). Baseline characteristics and blood samples were collected at d 0, 1, 2, 3, 7, 28, 56, 84 and 112 after the intervention. The blood biomarker levels were determined with standardized methods. Results: The intervention markedly increased the blood 25(OH)D3 levels within the first five days (mean Tmax=5.1±2.1 d) and sustained an optimal circulating level of 25(OH)D3 (≥30 ng/mL) for 56 d. After the intervention, body weight and baseline 25(OH)D3 levels were significantly correlated with circulating 25(OH)D3 levels. No adverse events and no consistently significant changes in serum calcium, creatinine, glucose, parathyroid hormone, vitamin D binding protein, or the urinary calcium/reatinine ratio were observed. However, there was a significant increase in phosphorus after the vitamin D3 intervention. Total cholesterol and triglyceride levels were decreased at the end of the trial. Conclusion: The pharmacokinetics of vitamin D after intervention were influenced by baseline 25(OH)D3 levels and the body weight of the subjects. The results suggest that a single high oral vitamin D3 intervention is safe and efficient for improving the vitamin D status of young Chinese people with vitamin D insufficiency. PMID:27569392

  19. Long-term vitamin D3 supplementation is more effective than vitamin D2 in maintaining serum 25-hydroxyvitamin D status over the winter months.

    PubMed

    Logan, Victoria F; Gray, Andrew R; Peddie, Meredith C; Harper, Michelle J; Houghton, Lisa A

    2013-03-28

    Public health recommendations do not distinguish between vitamin D2 and vitamin D3, yet disagreement exists on whether these two forms should be considered equivalent. The objective of the present study was to evaluate the effect of a daily physiological dose of vitamin D2 or vitamin D3 on 25-hydroxyvitamin D (25(OH)D) status over the winter months in healthy adults living in Dunedin, New Zealand (latitude 46°S). Participants aged 18-50 years were randomly assigned to 25 μg (1000 IU) vitamin D3 (n 32), 25 μg (1000 IU) vitamin D2 (n 31) or placebo (n 32) daily for 25 weeks beginning at the end of summer. A per-protocol approach, which included ≥ 90 % supplement compliance, was used for all analyses. Serum 25-hydroxyvitamin D3 (25(OH)D3), 25-hydroxyvitamin D2 (25(OH)D2) and parathyroid hormone (PTH) were measured at baseline and at 4, 8, 13 and 25 weeks. Geometric mean total serum 25(OH)D concentrations (sum of 25(OH)D2 and 25(OH)D3) at baseline was 80 nmol/l. After 25 weeks, participants randomised to D2 and placebo had a significant reduction in serum 25(OH)D3 concentrations over the winter months compared with vitamin D3-supplemented participants (both P< 0.001). Supplementation with vitamin D2 increased serum 25(OH)D2 but produced a 9 (95 % CI 1, 17) nmol/l greater decline in the 25(OH)D3 metabolite compared with placebo (P< 0.036). Overall, total serum 25(OH)D concentrations were 21 (95 % CI 14, 30) nmol/l lower in participants receiving vitamin D2 compared with those receiving D3 (P< 0.001), among whom total serum 25(OH)D concentrations remained unchanged. No intervention-related changes in PTH were observed. Daily supplementation of vitamin D3 was more effective than D2; however, the functional consequence of the differing metabolic response warrants further investigation.

  20. PKC and PTPα participate in Src activation by 1α,25OH2 vitamin D3 in C2C12 skeletal muscle cells.

    PubMed

    Buitrago, Claudia; Costabel, Marcelo; Boland, Ricardo

    2011-06-06

    We previously demonstrated that 1α,25(OH)(2)-vitamin D(3) [1α,25(OH)(2)D(3)] induces Src activation, which mediates the hormone-dependent ERK1/2 and p38 MAPK phosphorylation in skeletal muscle cells. In the present study, we have investigated upstream steps whereby 1α,25(OH)(2)D(3) may act to transmit its signal to Src. Preincubation with the PKC inhibitor Ro318220 demonstrated the participation of PKC in 1α,25(OH)(2)D(3)-dependent Src activation. Of interest, the hormone promoted the activation of δ the isoform of PKC. We also explored the role of PTPα in PKC-mediated Src stimulation. Silencing of PTPα with a specific siRNA suppressed Src activation induced by 1α,25(OH)(2)D(3). Hormone treatment increased PTPα (Tyr789) phosphorylation and PKC-dependent phosphatase activity. Accordingly, 1α,25(OH)(2)D(3) promoted serine phosphorylation of PTPα in a PKC-dependent manner. Confocal immunocytochemistry and co-immunoprecipitation assays revealed that the hormone induces the co-localization of Src and PTPα with PKC participation. Computational analysis revealed that the electrostatic interaction between Src and PTPα is favored when PTPα is phosphorylated in Tyr789. These data suggest that 1α,25(OH)(2)D(3) acts in skeletal muscle upstream on MAPK cascades sequentially activating PKC, PTPα and Src.

  1. Genome-wide association study of 25(OH) Vitamin D concentrations in Punjabi Sikhs: Results of the Asian Indian diabetic heart study.

    PubMed

    Sapkota, Bishwa R; Hopkins, Ruth; Bjonnes, Andrew; Ralhan, Sarju; Wander, Gurpreet S; Mehra, Narinder K; Singh, Jai Rup; Blackett, Piers R; Saxena, Richa; Sanghera, Dharambir K

    2016-04-01

    Vitamin D deficiency is implicated in multiple disease conditions and accumulating evidence supports that the variation in serum vitamin D (25(OH)D) levels, including deficiency, is under strong genetic control. However, the underlying genetic mechanism associated with vitamin 25(OH)D concentrations is poorly understood. We earlier reported a very high prevalence of vitamin D deficiency associated with an increased risk for type 2 diabetes and obesity in a Punjabi Sikh diabetic cohort as part of the Asian Indian diabetic heart study (AIDHS). Here we have performed the first genome-wide association study (GWAS) of serum 25(OH)D on 3538 individuals from this Punjabi Sikh population. Our discovery GWAS comprised of 1387 subjects followed by validation of 24 putative SNPs (P<10(-4)) using an independent replication sample (n=2151) from the same population by direct genotyping. A novel locus at chromosome 20p11.21 represented by rs2207173 with minor allele frequency (MAF) 0.29, [β=-0.13, p=4.47×10(-9)] between FOXA2 and SSTR4 was identified to be associated with 25(OH)D levels. Another suggestive association signal at rs11586313 (MAF 0.54) [β=0.90; p=1.36×10(-6)] was found within the regulatory region of the IVL gene on chromosome 1q21.3. Additionally, our study replicated 3 of 5 known GWAS genes associated with 25(OH)D concentrations including GC (p=0.007) and CYP2R1 (p=0.019) reported in Europeans and the DAB1 (p=0.003), reported in Hispanics. Identification of novel association signals in biologically plausible regions with 25(OH)D metabolism will provide new molecular insights on genetic drivers of vitamin D status and its implications in health disparities.

  2. 1alpha,25(OH)2-vitamin D3 membrane-initiated calcium signaling modulates exocytosis and cell survival.

    PubMed

    Xiaoyu, Zhang; Payal, Biswas; Melissa, Owraghi; Zanello, Laura P

    2007-03-01

    1alpha,25(OH)(2)-vitamin D(3) (1,25D) is considered a bone anabolic hormone. 1,25D actions leading to bone formation involve gene transactivation, on one hand, and modulation of cytoplasmic signaling, on the other. In both cases, a functional vitamin D receptor (VDR) appears to be required. Here we study 1,25D-stimulated calcium signaling that initiates at the cell membrane and leads to exocytosis of bone materials and increased osteoblast survival. We found that rapid 1,25D-induction of exocytosis couples to cytoplasmic calcium increase in osteoblastic ROS 17/2.8 cells. In addition, we found that elevation of cytoplasmic calcium concentration is involved in 1,25D anti-apoptotic effects via Akt activation in ROS 17/2.8 cells and non-osteoblastic CV-1 cells. In both cases, 1,25D-stimulated elevation of intracellular calcium is due in part to activation of L-type Ca(2+) channels. We conclude that 1,25D bone anabolic effects that involve increased intracellular Ca(2+) concentration in osteoblasts can be explained at two levels. At the single-cell level, 1,25D promotes Ca(2+)-dependent exocytotic activities. At the tissue level, 1,25D protects osteoblasts from apoptosis via a Ca(2+)-dependent Akt pathway. Our studies contribute to the understanding of the molecular basis of bone diseases characterized by decreased bone formation and mineralization.

  3. Effects of the Administration of 25(OH) Vitamin D3 in an Experimental Model of Chronic Kidney Disease in Animals Null for 1-Alpha-Hydroxylase

    PubMed Central

    Torremadé, Noelia; Bozic, Milica; Goltzman, David; Fernandez, Elvira

    2017-01-01

    The final step in vitamin D activation is catalyzed by 1-alpha-hydroxylase (CYP27B1). Chronic kidney disease (CKD) is characterized by low levels of both 25(OH)D3 and 1,25(OH)2D3 provoking secondary hyperparathyroidism (2HPT). Therefore, treatments with active or native vitamin D compounds are common in CKD to restore 25(OH)D3 levels and also to decrease PTH. This study evaluates the dose of 25(OH)D3 that restores parathyroid hormone (PTH) and calcium levels in a model of CKD in CYP27B1-/- mice. Furthermore, we compare the safety and efficacy of the same dose in CYP27B1+/+ animals. The dose needed to decrease PTH levels in CYP27B1-/- mice with CKD was 50 ng/g. That dose restored blood calcium levels without modifying phosphate levels, and increased the expression of genes responsible for calcium absorption (TRPV5 and calbindinD- 28K in the kidney, TRPV6 and calbindinD-9k in the intestine). The same dose of 25(OH)D3 did not modify PTH in CYP27B1+/+ animals with CKD. Blood calcium remained normal, while phosphate increased significantly. Blood levels of 25(OH)D3 in CYP27B1-/- mice were extremely high compared to those in CYP27B1+/+ animals. CYP27B1+/+ animals with CKD showed increases in TRPV5, TRPV6, calbindinD-28K and calbindinD-9K, which were not further elevated with the treatment. Furthermore, CYP27B1+/+ animals displayed an increase in vascular calcification. We conclude that the dose of 25(OH)D3 effective in decreasing PTH levels in CYP27B1-/- mice with CKD, has a potentially toxic effect in CYP27B1+/+ animals with CKD. PMID:28107527

  4. Interlaboratory Trial for Measurement of Vitamin D and 25-Hydroxyvitamin D [25(OH)D] in Foods and a Dietary Supplement Using Liquid Chromatography-Mass Spectrometry.

    PubMed

    Roseland, Janet Maxwell; Patterson, Kristine Y; Andrews, Karen W; Phillips, Katherine M; Phillips, Melissa M; Pehrsson, Pamela R; Dufresne, Guy L; Jakobsen, Jette; Gusev, Pavel A; Savarala, Sushma; Nguyen, Quynhanh V; Makowski, Andrew J; Scheuerell, Chad R; Larouche, Guillaume P; Wise, Stephen A; Harnly, James M; Williams, Juhi R; Betz, Joseph M; Taylor, Christine L

    2016-04-27

    Assessment of total vitamin D intake from foods and dietary supplements (DSs) may be incomplete if 25-hydroxyvitamin D [25(OH)D] intake is not included. However, 25(OH)D data for such intake assessments are lacking, no food or DS reference materials (RMs) are available, and comparison of laboratory performance has been needed. The primary goal of this study was to evaluate whether vitamin D3 and 25(OH)D3 concentrations in food and DS materials could be measured with acceptable reproducibility. Five experienced laboratories from the United States and other countries participated, all using liquid chromatography tandem-mass spectrometry but no common analytical protocol; however, various methods were used for determining vitamin D3 in the DS. Five animal-based materials (including three commercially available RMs) and one DS were analyzed. Reproducibility results for the materials were acceptable. Thus, it is possible to obtain consistent results among experienced laboratories for vitamin D3 and 25(OH)D3 in foods and a DS.

  5. Ca2(+)-channel agonist BAY K8644 mimics 1,25(OH)2-vitamin D3 rapid enhancement of Ca2+ transport in chick perfused duodenum

    SciTech Connect

    de Boland, A.R.; Nemere, I.; Norman, A.W. )

    1990-01-15

    To further understand the molecular mechanism by which 1,25(OH)2-vitamin D3 (1,25(OH)2D3) rapidly stimulates intestinal calcium transport (termed transcaltachia), the effect of the calcium channel agonist BAY K8644 was studied in vascularly perfused duodenal loops from normal, vitamin D-replete chicks. BAY K8644, 2 mu M, was found to stimulate {sup 45}Ca{sup 2+} transport from the lumen to the vascular effluent to the same extent as physiological levels of 1,25(OH)2D3. The sterol and the Ca{sup 2+} channel agonist both increased {sup 45}Ca{sup 2+} transport 70% above control values within 2 min and 200% after 30 min of vascular perfusion. The effect of the Ca{sup 2+} channel agonist was dose dependent. Also, 1,25(OH)2D3-enhanced transcaltachia was abolished by the calcium channel blocker nifedipine. Collectively, these results suggest the involvement of 1,25(OH)2D3 in the activation of basal lateral membrane Ca{sup 2+} channels as an early effect in the transcaltachic response.

  6. Vitamin D deficiency as a public health issue: using vitamin D2 or vitamin D3 in future fortification strategies.

    PubMed

    Wilson, Louise R; Tripkovic, Laura; Hart, Kathryn H; Lanham-New, Susan A

    2017-03-28

    The role of vitamin D in supporting the growth and maintenance of the skeleton is robust; with recent research also suggesting a beneficial link between vitamin D and other non-skeletal health outcomes, including immune function, cardiovascular health and cancer. Despite this, vitamin D deficiency remains a global public health issue, with a renewed focus in the UK following the publication of Public Health England's new Dietary Vitamin D Requirements. Natural sources of vitamin D (dietary and UVB exposure) are limited, and thus mechanisms are needed to allow individuals to achieve the new dietary recommendations. Mandatory or voluntary vitamin D food fortification may be one of the mechanisms to increase dietary vitamin D intakes and subsequently improve vitamin D status. However, for the food industry and public to make informed decisions, clarity is needed as to whether vitamins D2 and D3 are equally effective at raising total 25-hydroxyvitamin D (25(OH)D) concentrations as the evidence thus far is inconsistent. This review summarises the evidence to date behind the comparative efficacy of vitamins D2 and D3 at raising 25(OH)D concentrations, and the potential role of vitamin D food fortification as a public health policy to support attainment of dietary recommendations in the UK. The comparative efficacy of vitamins D2 and D3 has been investigated in several intervention trials, with most indicating that vitamin D3 is more effective at raising 25(OH)D concentrations. However, flaws in study designs (predominantly under powering) mean there remains a need for a large, robust randomised-controlled trial to provide conclusive evidence, which the future publication of the D2-D3 Study should provide (BBSRC DRINC funded: BB/I006192/1). This review also highlights outstanding questions and gaps in the research that need to be addressed to ensure the most efficacious and safe vitamin D food fortification practices are put in place. This further research, alongside cost

  7. Gestational Vitamin 25(OH)D Status as a Risk Factor for Receptive Language Development: A 24-Month, Longitudinal, Observational Study

    PubMed Central

    Tylavsky, Frances A.; Kocak, Mehmet; Murphy, Laura E.; Graff, J. Carolyn; Palmer, Frederick B.; Völgyi, Eszter; Diaz-Thomas, Alicia M.; Ferry, Robert J.

    2015-01-01

    Emerging data suggest that vitamin D status during childhood and adolescence can affect neurocognitive development. The purpose of this study was to investigate whether gestational 25(OH)D status is associated with early childhood cognitive and receptive language development. The Conditions Affecting Neurocognitive Development and Learning in Early Childhood Study (CANDLE) study enrolled 1503 mother-child dyads during the second trimester of healthy singleton pregnancies from Shelby County TN. Among 1020 participants of the total CANDLE cohort for whom 25(OH)D levels were available, mean gestational 25(OH)D level during the second trimester was 22.3 ng/mL (range 5.9–68.4), with 41.7% of values <20 ng/dL. Cognitive and language scaled scores increased in a stair-step manner as gestational 25(OH)D levels in the second trimester rose from <20 ng/dL, through 20–29.99 ng/dL, to ≥30 ng/dL. When controlling for socioeconomic status, race, use of tobacco products, gestational age of the child at birth, and age at the 2-year assessment, the gestational 25(OH)D was positively related to receptive language development (p < 0.017), but not cognitive or expressive language. PMID:26633480

  8. 25-OH vitamin D level has no impact on the efficacy of antiviral therapy in naïve genotype 1 HCV-infected patients

    PubMed Central

    Belle, Arthur; Gizard, Emmanuel; Conroy, Guillaume; Lopez, Anthony; Bouvier-Alias, Magali; Rouanet, Stéphanie; Peyrin-Biroulet, Laurent; Pawlotsky, Jean-Michel

    2016-01-01

    Background and aim The impact of 25-OH vitamin D on sustained viral response (SVR) to antiviral therapy and on fibrosis progression in hepatitis C is debated. We assessed the impact of 25-OH vitamin D concentration on the efficacy of antiviral therapy in naïve genotype 1 hepatitis C virus (HCV)-infected patients. Methods The study population consisted of treatment-naïve genotype 1 patients enrolled in a randomised controlled trial. A total of 516 patients received peginterferon α-2a 180 µg/week plus ribavirin 800 mg/day for 24 weeks. There were 349 patients with undetectable HCV RNA (<50 IU/ml) at week 24 (W24) who were randomised to continue dual therapy (n = 173) or to continue peginterferon alone (n = 176) until week 48. 25-OH vitamin D concentration was measured at baseline in frozen serum. Results A total of 461 patients could be analysed for virologic response at W24, and 285 (119 non-responders at W24 + 166 responders who continued dual therapy until W48) for the impact of SVR. There were 487 patients who could be analysed for fibrosis progression. Metavir fibrosis scores (centralised analysis) were: F1 30%, F2 34%, F3 27% and F4 9%. Median 25-OH vitamin D concentrations were similar in virologic responders (13.5 ng/ml) and in non-responders at W24 (12.6 ng/ml), as well as in patients with SVR (12.8 ng/ml) and without SVR (12.8 ng/ml, 3.99) at W72. Median 25-OH vitamin D concentrations were: F1: 14.30 ng/ml, F2: 13.50 ng/ml, F3: 13.30 ng/ml and F4: 12.80 ng/ml. Conclusion In this study, 25-OH vitamin D level has no impact on the efficacy of antiviral therapy in naïve genotype 1 HCV-infected patients.

  9. Comparison of vitamin D2 and vitamin D3 supplementation in raising serum 25-hydroxyvitamin D status: a systematic review and meta-analysis123

    PubMed Central

    Lambert, Helen; Hart, Kathryn; Smith, Colin P; Bucca, Giselda; Penson, Simon; Chope, Gemma; Hyppönen, Elina; Berry, Jacqueline; Vieth, Reinhold; Lanham-New, Susan

    2012-01-01

    Background: Currently, there is a lack of clarity in the literature as to whether there is a definitive difference between the effects of vitamins D2 and D3 in the raising of serum 25-hydroxyvitamin D [25(OH)D]. Objective: The objective of this article was to report a systematic review and meta-analysis of randomized controlled trials (RCTs) that have directly compared the effects of vitamin D2 and vitamin D3 on serum 25(OH)D concentrations in humans. Design: The ISI Web of Knowledge (January 1966 to July 2011) database was searched electronically for all relevant studies in adults that directly compared vitamin D3 with vitamin D2. The Cochrane Clinical Trials Registry, International Standard Randomized Controlled Trials Number register, and clinicaltrials.gov were also searched for any unpublished trials. Results: A meta-analysis of RCTs indicated that supplementation with vitamin D3 had a significant and positive effect in the raising of serum 25(OH)D concentrations compared with the effect of vitamin D2 (P = 0.001). When the frequency of dosage administration was compared, there was a significant response for vitamin D3 when given as a bolus dose (P = 0.0002) compared with administration of vitamin D2, but the effect was lost with daily supplementation. Conclusions: This meta-analysis indicates that vitamin D3 is more efficacious at raising serum 25(OH)D concentrations than is vitamin D2, and thus vitamin D3 could potentially become the preferred choice for supplementation. However, additional research is required to examine the metabolic pathways involved in oral and intramuscular administration of vitamin D and the effects across age, sex, and ethnicity, which this review was unable to verify. PMID:22552031

  10. Effect of calcium or 25OH vitamin D3 dietary supplementation on bone loss at the hip in men and women over the age of 60.

    PubMed

    Peacock, M; Liu, G; Carey, M; McClintock, R; Ambrosius, W; Hui, S; Johnston, C C

    2000-09-01

    Dietary supplements that prevent bone loss at the hip and that can be applied safely in the elderly are likely to reduce hip fractures. A daily dietary supplement of 750 mg calcium or 15 microg 25OH vitamin D3 on bone loss at the hip and other sites, bone turnover and calcium-regulating hormones were studied over 4 yr in elderly volunteers using a randomized, double-blind, placebo-controlled trial. Bone mineral density (BMD) was measured by dual x-ray absorptiometry and bone structure by radiographs. Calcium biochemistry and bone turnover markers were measured in blood and urine. The 316 women entering the trial had a mean age of 73.7 yr and the 122 men of 75.9 yr. Baseline median calcium intake was 546 mg/day, and median serum 25OH vitamin D3 was 59 nmol/L. On placebo, loss of BMD at total hip was 2% and femoral medulla expansion was 3% over 4 yr. Calcium reduced bone loss, secondary hyperparathyroidism, and bone turnover. 25OH vitamin D3 was intermediate between placebo and calcium. Fracture rates and drop-out rates were similar among groups, and there were no serious adverse events with either supplement. A calcium supplement of 750 mg/day prevents loss of BMD, reduces femoral medullary expansion, secondary hyperparathyroidism, and high bone turnover. A supplement of 15 microg/day 25OH vitamin D3 is less effective, and because its effects are seen only at low calcium intakes, suggests that its beneficial effect is to reverse calcium insufficiency.

  11. 1,25(OH) sub 2 D sub 3 and Ca-binding protein in fetal rats: Relationship to the maternal vitamin D status

    SciTech Connect

    Verhaeghe, J.; Thomasset, M.; Brehier, A.; Van Assche, F.A.; Bouillon, R. Institut National de la Sante et de la Recherche Medical )

    1988-04-01

    The autonomy and functional role of fetal 1,25-dihydroxyvitamin D{sub 3} (1,25(OH){sub 2}D{sub 3}) were investigated in nondiabetic and diabetic BB rats fed diets containing 0.85% calcium-0.7% phosphorus or 0.2% calcium and phosphorus and in semistarved rats on the low calcium-phosphorus diet. The changes in maternal and fetal plasma 1,25(OH){sub 2}D{sub 3} were similar: the levels were increased by calcium-phosphorus restriction and decreased by diabetes and semistarvation. Maternal and fetal 1,25(OH){sub 2}D{sub 3} levels were correlated. The vitamin D-dependent calcium-binding proteins (CaBP{sub 9K} and CaBP{sub 28K}) were measured in multiple maternal and fetal tissues and in the placenta of nondiabetic, diabetic, and calcium-phosphorus-restricted rats. The distributions of CaBP{sub 9K} and CaBP{sub 28K} in the pregnant rat were similar to that of the growing rat. The increased maternal plasma 1,25(OH){sub 2}D{sub 3} levels in calcium-phosphorus-restricted rats were associated with higher duodenal CaBP{sub 9K} and renal CaBPs, but placental CaBP{sub 9K} was not different. In diabetic pregnant rats, duodenal CaBP{sub 9K} was not different. In diabetic pregnant rats, duodenal CaBP{sub 9K} tended to be lower, while renal CaBPs were normal; placental CaBP{sub 9K} was decreased. The results indicate that in the rat fetal 1,25(OH){sub 2}D{sub 3} depends on maternal 1,25(OH){sub 2}D{sub 3} or on factors regulating maternal 1,25(OH){sub 2}D{sub 3}. The lack of changes in fetal CaBP in the presence of altered fetal plasma 1,25(OH){sub 2}D{sub 3} levels confirms earlier data showing that 1,25(H){sub 2}D{sub 3} has a limited hormonal function during perinatal development in the rat.

  12. Effects of diet and exercise on plasma vitamin D (25(OH)D) levels in Vietnamese immigrant elderly in Sydney, Australia.

    PubMed

    Brock, K; Cant, R; Clemson, L; Mason, R S; Fraser, D R

    2007-03-01

    Vitamin D deficiency may be associated with osteoporosis and fractures in the elderly. In Australia where there is a sizeable Vietnamese population, research has not yet clarified the roles of diet, exercise and sun exposure in determining vitamin D status. Plasma samples for 25-hydroxy-vitamin D (25(OH)D); dietary intake of vitamin D and calcium; muscle strength and sun exposure were measured and weekly dairy intake, exercise levels and smoking habits were surveyed in free-living elderly of Vietnamese and Australian/British origin. There was marginal vitamin D deficiency (<37 nmol/L 25(OH)D) in 63% of Vietnamese but only in 37% of Australian/British born. Low dairy intake and no vigorous exercise were best predictors of vitamin D deficiency in Vietnamese, taking into account age, gender, dietary intake and sun exposure. Since these migrant elderly may not get adequate sun exposure due to either clothing customs or cultural norms that encourage fair (untanned) skin, it is important to encourage increased exercise and dairy intake.

  13. Selective upregulation of the expression of plasma membrane calcium ATPase isoforms upon differentiation and 1,25(OH)2D3-vitamin treatment of colon cancer cells.

    PubMed

    Ribiczey, Polett; Papp, Béla; Homolya, László; Enyedi, Ágnes; Kovács, Tünde

    2015-08-14

    We have previously presented co-expression of the plasma membrane calcium ATPase isoforms 4b (PMCA4b) and 1b (PMCA1b) in colon carcinoma cells, and selective upregulation of PMCA4b during differentiation initiated by short chain fatty acids or post-confluent growth. Here we show that the induction of PMCA4b expression is a characteristic feature of the post-confluency-induced differentiation of both enterocyte-type and goblet cell-type colon cancer cells. Vitamin D3 (1,25(OH)2D3) is a well-known regulator of intestinal Ca(2+) absorption and of basic cell functions such as growth and differentiation in various cell types. As PMCA proteins are involved both in intestinal Ca(2+) absorption and adenocarcinoma cell differentiation, we investigated the effect of 1,25(OH)2D3 on PMCA expression in enterocyte-like colon carcinoma cells, and monitored its effect on the expression of various differentiation markers. 1,25(OH)2D3 stimulated PMCA1b, but not PMCA4b expression without modulating the expression of the majority of the differentiation markers examined. Caco-2 cells differentiated in post-confluent cultures present normal enterocyte-like intestinal epithelial phenotype. To better understand the role of PMCA proteins in vectorial Ca(2+) transport by enterocytes, we also studied their subcellular localization in mature polarized Caco-2 cells. Both PMCA isoforms were located to the basolateral membrane, and the PMCA-specific immunofluorescent signal was significantly higher in vitamin D3-treated cells, underlining the 1,25(OH)2D3-induced upregulation of PMCA (presumably 1b isoform) expression in differentiated Caco-2 cells. We suggest that while PMCA1b has a housekeeping function in colon cancer cells, PMCA4b participates in the reorganization of the Ca(2+) signalling machinery during cell differentiation. The subcellular localization of PMCA1b and its selective 1,25(OH)2D3-dependent upregulation indicate that this isoform may have a specific role in 1,25(OH)2D3

  14. Elevated serum 1,25(OH)2-vitamin D3 level attenuates renal tubulointerstitial fibrosis induced by unilateral ureteral obstruction in kl/kl mice

    PubMed Central

    Sun, Yujing; Zhou, Gengyin; Gui, Ting; Shimokado, Aiko; Nakanishi, Masako; Oikawa, Kosuke; Sato, Fuyuki; Muragaki, Yasuteru

    2014-01-01

    Previous studies have suggested that Klotho provides reno-protection against unilateral ureteral obstruction (UUO)-induced renal tubulointerstitial fibrosis (RTF). Because the existing studies are mainly performed using heterozygous Klotho mutant (HT) mice, we focused on the effect of UUO on homozygous Klotho mutant (kl/kl) mice. UUO kidneys from HT mice showed a significantly higher level of RTF and TGF-β/Smad3 signaling than wild-type (WT) mice, whereas both were greatly suppressed in kl/kl mice. Primary proximal tubular epithelial culture cells isolated from kl/kl mice showed no suppression in TGF-β1-induced epithelial mesenchymal transition (EMT) compared to those from HT mice. In the renal epithelial cell line NRK52E, a large amount of inorganic phosphate (Pi), FGF23, or calcitriol was added to the medium to mimic the in vivo homeostasis of kl/kl mice. Neither Pi nor FGF23 antagonized TGF-β1-induced EMT. In contrast, calcitriol ameliorated TGF-β1-induced EMT in a dose dependent manner. A vitamin D3-deficient diet normalized the serum 1,25 (OH)2 vitamin D3 level in kl/kl mice and enhanced UUO-induced RTF and TGF-β/Smad3 signaling. In conclusion, the alleviation of UUO-induced RTF in kl/kl mice was due to the TGF-β1 signaling suppression caused by an elevated serum 1, 25(OH)2 vitamin D3. PMID:25297969

  15. The Relationship between 25 (OH) D Levels (Vitamin D) and Bone Mineral Density (BMD) in a Saudi Population in a Community-Based Setting

    PubMed Central

    Alkhenizan, Abdullah; Mahmoud, Ahmed; Hussain, Aneela; Gabr, Alia; Alsoghayer, Suad; Eldali, Abdelmoneim

    2017-01-01

    Background Vitamin D deficiency has been linked to an increased risk of osteoporosis. Vitamin D deficiency has reached high levels in the Saudi population, but there is conflicting evidence both in the Saudi population, and worldwide, regarding the existence of a correlation between these low vitamin D levels and reduced BMD (bone mineral density), or osteoporosis. Objective The objective of this study was primarily to determine whether there was a correlation between vitamin D deficiency and osteoporosis in the Saudi population. We aimed to investigate whether the high levels of vitamin D deficiency and insufficiency would translate to higher prevalence of osteoporosis, and whether there is a correlation between vitamin D levels and bone mineral density. Materials and methods This was a community based cross sectional study conducted in the Family Medicine Clinics at King Faisal Specialist Hospital and Research Centre in Riyadh, Saudi Arabia. Electronic records of 1723 patients were reviewed. Laboratory and radiology results were collected, including vitamin D levels, calcium levels, and bone mineral density scan results. Results Among the whole population, 61.5% had moderate to severe vitamin D deficiency with levels less than 50nmol/L. 9.1% of the population had osteoporosis, and 38.6% had osteopenia. Among the whole population, there was no significant correlation between spine or total femoral BMD and serum 25(OH) D. Conclusion Vitamin D deficiency is prevalent in the Saudi population. However, no correlation has been found between vitamin D deficiency and reduced bone mineral density in any age group, in males or females, Saudis or Non-Saudis, in our population in Riyadh, Saudi Arabia. PMID:28046015

  16. 1α,25(OH)2-3-Epi-Vitamin D3, a Natural Physiological Metabolite of Vitamin D3: Its Synthesis, Biological Activity and Crystal Structure with Its Receptor

    PubMed Central

    Molnár, Ferdinand; Sigüeiro, Rita; Sato, Yoshiteru; Araujo, Clarisse; Schuster, Inge; Antony, Pierre; Peluso, Jean; Muller, Christian; Mouriño, Antonio; Moras, Dino; Rochel, Natacha

    2011-01-01

    Background The 1α,25-dihydroxy-3-epi-vitamin-D3 (1α,25(OH)2-3-epi-D3), a natural metabolite of the seco-steroid vitamin D3, exerts its biological activity through binding to its cognate vitamin D nuclear receptor (VDR), a ligand dependent transcription regulator. In vivo action of 1α,25(OH)2-3-epi-D3 is tissue-specific and exhibits lowest calcemic effect compared to that induced by 1α,25(OH)2D3. To further unveil the structural mechanism and structure-activity relationships of 1α,25(OH)2-3-epi-D3 and its receptor complex, we characterized some of its in vitro biological properties and solved its crystal structure complexed with human VDR ligand-binding domain (LBD). Methodology/Principal Findings In the present study, we report the more effective synthesis with fewer steps that provides higher yield of the 3-epimer of the 1α,25(OH)2D3. We solved the crystal structure of its complex with the human VDR-LBD and found that this natural metabolite displays specific adaptation of the ligand-binding pocket, as the 3-epimer maintains the number of hydrogen bonds by an alternative water-mediated interaction to compensate the abolished interaction with Ser278. In addition, the biological activity of the 1α,25(OH)2-3-epi-D3 in primary human keratinocytes and biochemical properties are comparable to 1α,25(OH)2D3. Conclusions/Significance The physiological role of this pathway as the specific biological action of the 3-epimer remains unclear. However, its high metabolic stability together with its significant biologic activity makes this natural metabolite an interesting ligand for clinical applications. Our new findings contribute to a better understanding at molecular level how natural metabolites of 1α,25(OH)2D3 lead to significant activity in biological systems and we conclude that the C3-epimerization pathway produces an active metabolite with similar biochemical and biological properties to those of the 1α,25(OH)2D3. PMID:21483824

  17. Vitamin D2 Supplementation Amplifies Eccentric Exercise-Induced Muscle Damage in NASCAR Pit Crew Athletes

    PubMed Central

    Nieman, David C.; Gillitt, Nicholas D.; Shanely, R. Andrew; Dew, Dustin; Meaney, Mary Pat; Luo, Beibei

    2013-01-01

    This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day) had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) in National Association for Stock Car Auto Racing (NASCAR) NASCAR pit crew athletes. Subjects were randomized to vitD2 (n = 13) and placebo (n = 15), and ingested supplements (double-blind) for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test). Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OH)D2 456% and decreased 25(OH)D3 21% versus placebo (p < 0.001, p = 0.036, respectively), with no influence on muscle function test scores. The post-study eccentric exercise bout induced EIMD and DOMS, with higher muscle damage biomarkers measured in vitD2 compared to placebo (myoglobin 252%, 122% increase, respectively, p = 0.001; creatine phosphokinase 24 h post-exercise, 169%, 32%, p < 0.001), with no differences for DOMS. In summary, 6-weeks vitD2 (3800 IU/day) significantly increased 25(OH)D2 and decreased 25(OH)D3, had no effect on muscle function tests, and amplified muscle damage markers in NASCAR pit crew athletes following eccentric exercise. PMID:24362707

  18. Vitamin D2 supplementation amplifies eccentric exercise-induced muscle damage in NASCAR pit crew athletes.

    PubMed

    Nieman, David C; Gillitt, Nicholas D; Shanely, R Andrew; Dew, Dustin; Meaney, Mary Pat; Luo, Beibei

    2013-12-20

    This study determined if 6-weeks vitamin D2 supplementation (vitD2, 3800 IU/day) had an influence on muscle function, eccentric exercise-induced muscle damage (EIMD), and delayed onset of muscle soreness (DOMS) in National Association for Stock Car Auto Racing (NASCAR) NASCAR pit crew athletes. Subjects were randomized to vitD2 (n=13) and placebo (n=15), and ingested supplements (double-blind) for six weeks. Blood samples were collected and muscle function tests conducted pre- and post-study (leg-back and hand grip dynamometer strength tests, body weight bench press to exhaustion, vertical jump, 30-s Wingate test). Post-study, subjects engaged in 90 min eccentric-based exercise, with blood samples and DOMS ratings obtained immediately after and 1- and 2-days post-exercise. Six weeks vitD2 increased serum 25(OH)D2 456% and decreased 25(OH)D3 21% versus placebo (p<0.001, p=0.036, respectively), with no influence on muscle function test scores. The post-study eccentric exercise bout induced EIMD and DOMS, with higher muscle damage biomarkers measured in vitD2 compared to placebo (myoglobin 252%, 122% increase, respectively, p=0.001; creatine phosphokinase 24 h post-exercise, 169%, 32%, p<0.001), with no differences for DOMS. In summary, 6-weeks vitD2 (3800 IU/day) significantly increased 25(OH)D2 and decreased 25(OH)D3, had no effect on muscle function tests, and amplified muscle damage markers in NASCAR pit crew athletes following eccentric exercise.

  19. 21 CFR 172.379 - Vitamin D2.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Vitamin D2. 172.379 Section 172.379 Food and Drugs... Dietary and Nutritional Additives § 172.379 Vitamin D2. Vitamin D2 may be used safely in foods as a... prescribed conditions: (a) Vitamin D2, also known as ergocalciferol, is the chemical...

  20. 21 CFR 172.379 - Vitamin D2.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Vitamin D2. 172.379 Section 172.379 Food and Drugs... Dietary and Nutritional Additives § 172.379 Vitamin D2. Vitamin D2 may be used safely in foods as a... prescribed conditions: (a) Vitamin D2, also known as ergocalciferol, is the chemical...

  1. 21 CFR 172.379 - Vitamin D2.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Vitamin D2. 172.379 Section 172.379 Food and Drugs... Dietary and Nutritional Additives § 172.379 Vitamin D2. Vitamin D2 may be used safely in foods as a... prescribed conditions: (a) Vitamin D2, also known as ergocalciferol, is the chemical...

  2. 21 CFR 172.379 - Vitamin D2.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Vitamin D2. 172.379 Section 172.379 Food and Drugs... Dietary and Nutritional Additives § 172.379 Vitamin D2. Vitamin D2 may be used safely in foods as a... prescribed conditions: (a) Vitamin D2, also known as ergocalciferol, is the chemical...

  3. Serum 25(OH) Vitamin D levels is not associated with disability in multiple sclerosis patients: A case-control study

    PubMed Central

    Nikanfar, Masoud; Taheri-Aghdam, Ali Akbar; Yazdani, Maria; Shaafi, Sheida; Masoudian, Nooshin; Akbari, Hossein; Youhanaee, Parisa; Abbaszadeh, Hamzeh

    2015-01-01

    Background: It seems that serum vitamin D levels are one of the potential environmental factors affecting the severity of multiple sclerosis (MS). In this study, we aim to evaluate vitamin D levels in MS patients and healthy subjects and assess the relationship between vitamin D level and disability. Methods: In this case-control study, 168 rapid relapsing MS patients and 168 matched healthy controls were randomly included in this study. Demographic characteristics and serum vitamin D levels for patients and controls, as well as expanded disability status scale (EDSS), duration of disease and diagnostic lag for patients were evaluated. We followed up patients for 6 months and relapses were recorded. Results: The mean serum vitamin D levels were 19.16 ± 17.37 inpatients and 25.39 ± 19.67 in controls (P = 0.560). The mean serum vitamin D levels were 12.65 ± 13.3 in patients with relapses and 22.08 ± 18.22 in patients without any relapses (P < 0.001). There was no significant correlation between EDSS score and serum vitamin D levels (r = −0.08, P = 0.280). There was a significant positive correlation between EDSS score and disease duration (r = 0.52, P < 0.001). Conclusion: In conclusion, vitamin D level in patients with MS was significantly lower than the healthy subjects, but no significant relationship was found between vitamin D levels and disability. Our findings did not suggest a protective role for serum vitamin D levels against disability. PMID:25874052

  4. Dosage de la 25 OH vitamine D: expérience du laboratoire central de biochimie clinique du Centre Hospitalier Ibn Sina

    PubMed Central

    Handor, Najat; Elalami, Sanae; Bouabdellah, Mounya; Srifi, Abdelatif; Esselmani, Hicham; Benchekroun, Laila; Chabraoui, Layachi

    2014-01-01

    La connaissance de la physiologie de la vitamine D a considérablement progressé ces dernières années, la faisant passer de simple vitamine à tropisme purement phosphocalcique et osseux à celui d'hormone jouant un rôle crucial dans de nombreux mécanismes physiologiques et dont le déficit est impliqué dans plusieurs pathologies. Nous présentons, dans ce travail, l'expérience du laboratoire central de biochimie dans le dosage de la 25 OH vitamine D. Enquête descriptive exhaustive portant sur les dosages de la 25 OH vitamine D effectués chez 350 patients du Centre Hospitalier Ibn Sina (CHIS). La méthode adoptée est un dosage immunologique par chimiluminescence sur microparticules réalisés sur l'auto-analyseur ARCHITECT 8200 (ABBOTT®) pendant une période de six mois (du 01 Juin 2011 au 31 Decembre 2011). Quatre vingt et onze pourcent des patients présentent une hypovitaminose. En effet 76,6% des patients souffrent d'une insuffisance en vitamine D, 12,3% de carence vitaminique et 2,6% d'ostéomalacie. L'hypovitaminose est associée dans 92,18% des cas à une normocalcémie, dans 76,87% des cas à une Hyperparathormone, dans 92,81% à des troubles thyroïdiens et dans 97,5% à une insuffisance rénale. Par ailleurs aucune relation statistiquement significative n'est établie entre l'hypovitaminose et le diabète. A la lumière des implications des hypovitaminoses dans plusieurs pathologies ou dans leurs complications et au vu du nombre élevé de patients présentant un déficit en vitamine D, il paraît judicieux d'envisager une étude épidémiologique sur le statut en vitamine D dans la population marocaine comme outil préventif avant d'élargir le dosage de ce marqueur biologique en vue d'une éventuelle supplémentation. PMID:25374649

  5. Active vitamin D3, 1,25-(OH)2D3, protects against macrovasculopathy in a rat model of type 2 diabetes mellitus.

    PubMed

    Ma, R; Deng, X L; Du, G L; Li, C; Xiao, S; Aibibai, Y; Zhu, J

    2016-06-03

    To investigate the protective effect of the active form of vitamin D3, 1,25-(OH)2D3, on macrovasculopathy in rats with type 2 diabetes mellitus (T2DM), 8-week-old male Sprague-Dawley rats were randomly divided into control group, T2DM group, and treatment group. The T2DM model was established after 6 weeks by administering an intraperitoneal injection of streptozotocin (30 mg/kg). 1,25-(OH)2D3 was administered by gavage to rats in the treatment group, and an equal volume of peanut oil was administered to rats in the T2DM group. Fasting plasma glucose (FPG), triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL-C) and low-density lipoprotein (LDL-C) cholesterols were measured in all rats. The morphology of the thoracic aorta was examined, and the expression of tumor necrosis factor alpha (TNF-α), endothelin (ET), endothelial nitric oxide synthase (eNOS), CD54, and CD106 in the thoracic aorta was determined by immunohistochemistry. The expression of FPG, TG, TC, and LDL-C in rats from the T2DM and treatment groups was significantly elevated compared with rats from the control group (P < 0.05). Compared with that in control group, the expression of TNF-α, ET, eNOS, and CD106 was significantly upregulated in the T2DM group and the treatment group, while the expression of CD54 was increased only in the T2DM group (P < 0.05). Moreover, the levels of TNF-α, CD54, and CD106 in rats from the treatment group were lower than those in the T2DM group (P < 0.05). These data suggest that 1,25-(OH)2D3 may protect the macrovessels from injury in T2DM rats by inhibiting the expression of TNF-α, CD54, and CD106.

  6. 1α,25(OH)2 Vitamin D3 Modulates Avian T Lymphocyte Functions without Inducing CTL Unresponsiveness

    PubMed Central

    Boodhoo, Nitish; Sharif, Shayan; Behboudi, Shahriar

    2016-01-01

    1,25-Dihydroxyvitamin D3 (Vitamin D) is a naturally synthesized fat soluble vitamin shown to have immunomodulatory, anti-inflammatory and cancer prevention properties in human and murine models. Here, we studied the effects of Vitamin D on the functional abilities of avian T lymphocytes using chicken Interferon (IFN)-γ ELISPOT assay, BrdU proliferation assay, Annexin V apoptosis assay and PhosFlow for detecting phosphorylated signalling molecules. The results demonstrate that Vitamin D significantly inhibited the abilities of T lymphocytes to produce IFN-γ and proliferate in vitro (P≤0.05), but retained their ability to undergo degranulation, which is a maker for cytotoxicity of these cells. Similarly, Vitamin D did not inhibit Extracellular signal-Regulated Kinase (ERK) 1/2 phosphorylation, a key mediator in T cell signalling, in the stimulated T lymphocytes population, while reduced ERK1/2 phosphorylation levels in the unstimulated cells. Our data provide evidence that Vitamin D has immuno-modulatory properties on chicken T lymphocytes without inducing unresponsiveness and by limiting immuno-pathology can promote protective immunity against infectious diseases of poultry. PMID:26910045

  7. In vivo production of novel vitamin D2 hydroxy-derivatives by human placentas, epidermal keratinocytes, Caco-2 colon cells and the adrenal gland

    PubMed Central

    Slominski, Andrzej T.; Kim, Tae-Kang; Shehabi, Haleem Z.; Tang, Edith; Benson, Heather A. E.; Semak, Igor; Lin, Zongtao; Yates, Charles R.; Wang, Jin; Li, Wei; Tuckey, Robert C.

    2014-01-01

    We investigated the metabolism of vitamin D2 to hydroxyvitamin D2 metabolites ((OH)D2) by human placentas ex-utero, adrenal glands ex-vivo and cultured human epidermal keratinocytes and colonic Caco-2 cells, and identified 20(OH)D2, 17,20(OH)2D2, 1,20(OH)2D2, 25(OH)D2 and 1,25(OH)2D2 as products. Inhibition of product formation by 22R-hydroxycholesterol indicated involvement of CYP11A1 in 20- and 17-hydroxylation of vitamin D2, while use of ketoconazole indicated involvement of CYP27B1 in 1α-hydroxylation of products. Studies with purified human CYP11A1 confirmed the ability of this enzyme to convert vitamin D2 to 20(OH)D2 and 17,20(OH)2D2. In placentas and Caco-2 cells, production of 20(OH)D2 was higher than 25(OH)D2 while in human keratinocytes the production of 20(OH)D2 and 25(OH)D2 were comparable. HaCaT keratinocytes showed high accumulation of 1,20(OH)2D2 relative to 20(OH)D2 indicating substantial CYP27B1 activity. This is the first in vivo evidence for a novel pathway of vitamin D2 metabolism initiated by CYP11A1 and modified by CYP27B1, with the product profile showing tissue- and cell-type specificity. PMID:24382416

  8. In vivo production of novel vitamin D2 hydroxy-derivatives by human placentas, epidermal keratinocytes, Caco-2 colon cells and the adrenal gland.

    PubMed

    Slominski, Andrzej T; Kim, Tae-Kang; Shehabi, Haleem Z; Tang, Edith K Y; Benson, Heather A E; Semak, Igor; Lin, Zongtao; Yates, Charles R; Wang, Jin; Li, Wei; Tuckey, Robert C

    2014-03-05

    We investigated the metabolism of vitamin D2 to hydroxyvitamin D2 metabolites ((OH)D2) by human placentas ex-utero, adrenal glands ex-vivo and cultured human epidermal keratinocytes and colonic Caco-2 cells, and identified 20(OH)D2, 17,20(OH)₂D2, 1,20(OH)₂D2, 25(OH)D2 and 1,25(OH)₂D2 as products. Inhibition of product formation by 22R-hydroxycholesterol indicated involvement of CYP11A1 in 20- and 17-hydroxylation of vitamin D2, while use of ketoconazole indicated involvement of CYP27B1 in 1α-hydroxylation of products. Studies with purified human CYP11A1 confirmed the ability of this enzyme to convert vitamin D2 to 20(OH)D2 and 17,20(OH)₂D2. In placentas and Caco-2 cells, production of 20(OH)D2 was higher than 25(OH)D2 while in human keratinocytes the production of 20(OH)D2 and 25(OH)D2 were comparable. HaCaT keratinocytes showed high accumulation of 1,20(OH)₂D2 relative to 20(OH)D2 indicating substantial CYP27B1 activity. This is the first in vivo evidence for a novel pathway of vitamin D2 metabolism initiated by CYP11A1 and modified by CYP27B1, with the product profile showing tissue- and cell-type specificity.

  9. 21 CFR 172.381 - Vitamin D2 bakers yeast.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Vitamin D2 bakers yeast. 172.381 Section 172.381... CONSUMPTION Special Dietary and Nutritional Additives § 172.381 Vitamin D2 bakers yeast. Vitamin D2 bakers yeast may be used safely in foods as a source of vitamin D2 and as a leavening agent in accordance...

  10. 21 CFR 172.379 - Vitamin D2.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Vitamin D2. 172.379 Section 172.379 Food and Drugs....379 Vitamin D2. Vitamin D2 may be used safely in foods as a nutrient supplement defined under § 170.3(o)(20) of this chapter in accordance with the following prescribed conditions: (a) Vitamin D2,...

  11. 21 CFR 172.381 - Vitamin D2 bakers yeast.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Vitamin D2 bakers yeast. 172.381 Section 172.381... Additives § 172.381 Vitamin D2 bakers yeast. Vitamin D2 bakers yeast may be used safely in foods as a source of vitamin D2 and as a leavening agent in accordance with the following prescribed conditions:...

  12. Determinants of Vitamin D Levels in Italian Children and Adolescents: A Longitudinal Evaluation of Cholecalciferol Supplementation versus the Improvement of Factors Influencing 25(OH)D Status

    PubMed Central

    Stagi, Stefano; Pelosi, Paola; Strano, Massimo; Poggi, Giovanni; Manoni, Cristina; de Martino, Maurizio; Seminara, Salvatore

    2014-01-01

    Objective. This paper aims to assess 25(OH)D levels in Italian children and adolescents identifying risk factors for 25(OH)D deficiency and to evaluate whether a normal 25(OH)D value can be restored in 25(OH)D-deficient patients. Methods. We evaluated 25(OH)D levels in 679 Italian children and adolescents (≤10, 11–20, 21–30, and >30 ng/mL were defined as severe deficiency, deficiency, insufficiency, and sufficiency, resp.). Of these, 365 25(OH)D-deficient were followed up for 1 year; 205 were treated with cholecalciferol (Arm A: 400 I.U.) and 160 by improving the environmental variables influencing 25(OH)D levels (Arm B). Results. At cross-sectional evaluation, 11.3% showed sufficiency, 30.0% insufficiency, and 58.7% 25(OH)D deficiency. Mean 25(OH)D was 19.08 ± 8.44 ng/mL. At the enrollment time (T0), no difference was found between Arms A and B with respect to distribution and 25(OH)D levels. At end time (T1) 26.0% (29.7% in Arm A versus 20.6% in Arm B) showed sufficiency, 38.4% (42.0% versus 34.4%) insufficiency, and 35.6% (28.3% versus 45.0%) 25(OH)D deficiency. Mean 25(OH)D level was 23.71 ± 6.83 ng/mL. Conclusions. Neither changes of lifestyle nor 400 I.U. cholecalciferol supplementation alone appears to be sufficient to restore adequate 25(OH)D levels. PMID:25435877

  13. 21 CFR 582.5950 - Vitamin D 2.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Vitamin D 2. 582.5950 Section 582.5950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5950 Vitamin D 2. (a) Product. Vitamin D2. (b) Conditions of use. This substance...

  14. 21 CFR 582.5950 - Vitamin D2.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Vitamin D2. 582.5950 Section 582.5950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5950 Vitamin D2. (a) Product. Vitamin D2. (b) Conditions of use. This substance is...

  15. 21 CFR 582.5950 - Vitamin D2.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Vitamin D2. 582.5950 Section 582.5950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5950 Vitamin D2. (a) Product. Vitamin D2. (b) Conditions of use. This substance is...

  16. 21 CFR 582.5950 - Vitamin D 2.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Vitamin D 2. 582.5950 Section 582.5950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5950 Vitamin D 2. (a) Product. Vitamin D2. (b) Conditions of use. This substance...

  17. 21 CFR 582.5950 - Vitamin D2.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Vitamin D2. 582.5950 Section 582.5950 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5950 Vitamin D2. (a) Product. Vitamin D2. (b) Conditions of use. This substance is...

  18. Vitamin D delays breast cancer progression in the PyVMT transgenic mouse model: local conversion of the precursor 25(OH)D3 into 1,25(OH)2D3 is safer and more effective than systemic administration of 1,25(OH)2D3

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Metabolic activation of 1,25(OH)2D3 occurs at extra renal sites in several organs, including the breast. The purpose of this study was to determine if this local tumoral 25OHD3-1alphahydroxylase expression modulates any or all of the stages of breast tumor progression. For this purpose we used the...

  19. Actions of 1,25(OH)2-vitamin D3 on the cellular cycle depend on VDR and p38 MAPK in skeletal muscle cells.

    PubMed

    Irazoqui, Ana P; Boland, Ricardo L; Buitrago, Claudia G

    2014-12-01

    Previously, we have reported that 1,25(OH)2-vitamin D3 (1,25D) activates p38 MAPK (p38) in a vitamin D receptor (VDR)-dependent manner in proliferative C2C12 myoblast cells. It was also demonstrated that 1,25D promotes muscle cell proliferation and differentiation. However, we did not study these hormone actions in depth. In this study we have investigated whether the VDR and p38 participate in the signaling mechanism triggered by 1,25D. In C2C12 cells, the VDR was knocked down by a shRNA, and p38 was specifically inhibited using SB-203580. Results from cell cycle studies indicated that hormone stimulation prompts a peak of S-phase followed by an arrest in the G0/G1-phase, events which were dependent on VDR and p38. Moreover, 1,25D increases the expression of cyclin D3 and the cyclin-dependent kinase inhibitors, p21(Waf1/Cip1) and p27(Kip1), while cyclin D1 protein levels did not change during G0/G1 arrest. In all these events, p38 and VDR were required. At the same time, a 1,25D-dependent acute increase in myogenin expression was observed, indicating that the G0/G1 arrest of cells is a pro-differentiative event. Immunocytochemical assays revealed co-localization of VDR and cyclin D3, promoted by 1,25D in a p38-dependent manner. When cyclin D3 expression was silenced, VDR and myogenin levels were downregulated, indicating that cyclin D3 was required for 1,25D-induced VDR expression and the concomitant entrance into the differentiation process. In conclusion, the VDR and p38 are involved in control of the cellular cycle by 1,25D in skeletal muscle cells, providing key information on the mechanisms underlying hormone regulation of myogenesis.

  20. Hepatocellular carcinoma cells express 25(OH)D-1α-hydroxylase and are able to convert 25(OH)D to 1α,25(OH)₂D, leading to the 25(OH)D-induced growth inhibition.

    PubMed

    Chiang, Kun-Chun; Yen, Cho-Li; Yeh, Chun-Nan; Hsu, Jun-Te; Chen, Li-Wei; Kuo, Sheng-Fong; Wang, Shang-Yu; Sun, Chi-Chin; Kittaka, Atsushi; Chen, Tai C; Yeh, Ta-Sen; Hsu, Shu-Yuan; Juang, Horng-Heng

    2015-11-01

    Hepatocellular carcinoma (HCC) is the most diagnosed liver cancer without effective treatments available for advanced HCC. Vitamin D is getting popular due to its anti-cancer characteristics. However, the clinical application of 1α,25(OH)2D, the active form of vitamin, is hampered by its hypercalcemia side effect. 1α,25(OH)2D is converted from 25(OH)D, the index of serum vitamin D status, by CYP27B1, which is originally found in kidneys but recently detected in non-renal tissues. 25(OH)D has been shown to repress some cancers expressing CYP27B1 due to the local conversion of 25(OH)D to 1α,25(OH)2D, which works in a intra-, auto-, or paracrine manner and thus minimizes the risk of hypercalcemia. In this study, we found CYP27B1 expression in human hepatocyte, HCC, and HepG2 cells. As we treated HepG2 cells with 25(OH)D, the 1α,25(OH)2D target gene CYP24A1 expression was increased and was further upregulated as CYP27B1 transfection or downregulated as CYP27B1 knockdown. Other 1α,25(OH)2D target genes in HepG2 cells, p21 and p27 were also stimulated by 25(OH)D after CYP27B1 transfection. Further, 25(OH)D could inhibit HepG2 cells growth, which was potentiated by CYP27B1 transfection. Collectively, we showed for the first time that HCC expressed CYP27B1 and was able to covert 25(OH)D to 1α,25(OH)2D in vitro, thus responsive to 25(OH)D treatment. Our data justifies the application of 25(OH)D and CYP27B1 gene transfection therapy in further HCC treatment studies.

  1. Determination of vitamins D2, D3, K1 and K3 and some hydroxy metabolites of vitamin D3 in plasma using a continuous clean-up-preconcentration procedure coupled on-line with liquid chromatography-UV detection.

    PubMed

    Ortiz Boyer, F; Fernández Romero, J M; Luque de Castro, M D; Quesada, J M

    1999-03-01

    A semi-automatic procedure for the continuous clean-up and concentration of several fat-soluble vitamins prior to their separation by HPLC and UV detection is reported. The procedure is based on the use of a minicolumn packed with aminopropylsilica as sorbent located prior to the chromatographic detection system. The overall process was developed and applied to the main liposoluble vitamins (A, D2, D3, E, K1, K3) and several hydroxy metabolites of vitamin D3 [25-(OH)-D3,24,25-(OH)2-D3 and 1,25-(OH)2-D3]. All the analytes were monitored at a compromise wavelength of 270 nm. Calibration graphs were constructed between 0.01 and 100 ng ml-1 for vitamin D2 and D3 and their hydroxy metabolites, between 0.1 and 100 ng ml-1 for vitamin A, K1 and K3 and between 1 and 100 ng ml-1 for vitamin E, with excellent regression coefficients (> or = 0.9901) in all cases. The precision was established at two concentration levels with acceptable RSDs in all instances (between 3.6 and 8.7%). The method was appropriate for the determination of vitamin D2, D3, K1 and K3 and the 24,25-dihydroxy and 25-hydroxy metabolites of vitamin D3 in human plasma. The method was applied to plasma samples spiked with the target analytes and the recoveries ranged between 78 and 109%.

  2. Vector-averaged gravity-induced changes in cell signaling and vitamin D receptor activity in MG-63 cells are reversed by a 1,25-(OH)2D3 analog, EB1089

    NASA Technical Reports Server (NTRS)

    Narayanan, R.; Smith, C. L.; Weigel, N. L.

    2002-01-01

    Skeletal unloading in an animal hindlimb suspension model and microgravity experienced by astronauts or as a result of prolonged bed rest causes site-specific losses in bone mineral density of 1%-2% per month. This is accompanied by reductions in circulating levels of 1,25-(OH)(2)D(3), the active metabolite of vitamin D. 1,25-(OH)(2)D(3), the ligand for the vitamin D receptor (VDR), is important for calcium absorption and plays a role in differentiation of osteoblasts and osteoclasts. To examine the responses of cells to activators of the VDR in a simulated microgravity environment, we used slow-turning lateral vessels (STLVs) in a rotating cell culture system. We found that, similar to cells grown in microgravity, MG-63 cells grown in the STLVs produce less osteocalcin, alkaline phosphatase, and collagen Ialpha1 mRNA and are less responsive to 1,25-(OH)(2)D(3). In addition, expression of VDR was reduced. Moreover, growth in the STLV caused activation of the stress-activated protein kinase pathway (SAPK), a kinase that inhibits VDR activity. In contrast, the 1,25-(OH)(2)D(3) analog, EB1089, was able to compensate for some of the STLV-associated responses by reducing SAPK activity, elevating VDR levels, and increasing expression of osteocalcin and alkaline phosphatase. These studies suggest that, not only does simulated microgravity reduce differentiation of MG-63 cells, but the activity of the VDR, an important regulator of bone metabolism, is reduced. Use of potent, less calcemic analogs of 1,25-(OH)(2)D(3) may aid in overcoming this defect. Copyright 2002 Elsevier Science Inc.

  3. Vector-averaged gravity-induced changes in cell signaling and vitamin D receptor activity in MG-63 cells are reversed by a 1,25-(OH)2D3 analog, EB1089.

    PubMed

    Narayanan, R; Smith, C L; Weigel, N L

    2002-09-01

    Skeletal unloading in an animal hindlimb suspension model and microgravity experienced by astronauts or as a result of prolonged bed rest causes site-specific losses in bone mineral density of 1%-2% per month. This is accompanied by reductions in circulating levels of 1,25-(OH)(2)D(3), the active metabolite of vitamin D. 1,25-(OH)(2)D(3), the ligand for the vitamin D receptor (VDR), is important for calcium absorption and plays a role in differentiation of osteoblasts and osteoclasts. To examine the responses of cells to activators of the VDR in a simulated microgravity environment, we used slow-turning lateral vessels (STLVs) in a rotating cell culture system. We found that, similar to cells grown in microgravity, MG-63 cells grown in the STLVs produce less osteocalcin, alkaline phosphatase, and collagen Ialpha1 mRNA and are less responsive to 1,25-(OH)(2)D(3). In addition, expression of VDR was reduced. Moreover, growth in the STLV caused activation of the stress-activated protein kinase pathway (SAPK), a kinase that inhibits VDR activity. In contrast, the 1,25-(OH)(2)D(3) analog, EB1089, was able to compensate for some of the STLV-associated responses by reducing SAPK activity, elevating VDR levels, and increasing expression of osteocalcin and alkaline phosphatase. These studies suggest that, not only does simulated microgravity reduce differentiation of MG-63 cells, but the activity of the VDR, an important regulator of bone metabolism, is reduced. Use of potent, less calcemic analogs of 1,25-(OH)(2)D(3) may aid in overcoming this defect.

  4. Development of a Sensitive LC/MS/MS Method for Vitamin D Metabolites: 1,25 Dihydroxyvitamin D2&3 Measurement Using a Novel Derivatization Agent

    PubMed Central

    Hedman, Curtis J.; Wiebe, Donald A.; Dey, Subhakar; Plath, Josh; Kemnitz, Joseph W.; Ziegler, Toni E.

    2014-01-01

    Active vitamin D metabolites 1,25-dihydroxyvitamin D2 [1,25-(OH)2-D2; derived from ergocalciferol] and D3 [1,25-(OH)2-D3; derived from cholecalciferol] are found in low levels in the circulation and require a very sensitive method for measurement. Radioimmunoassay (RIA) has been the method of choice, but it lacks the specificity needed to distinguish between 1,25-(OH)2-D2 and -D3whereas liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods have the advantage of high specificity and sensitivity. Here, we compare a new derivative for ionizing 1,25-(OH)2-D to enhance the signal and provide the most sensitive assay for measuring vitamin D. We used the Amplifex diene method of derivatizing prior to LC/MS/MS and compared it to the standard RIA method and the 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) method of derivatizing prior to LC/MS/MS. In the evaluation of 20 human serum samples, all methods correlated strongly across the upper levels of the standard 1,25-(OH)2-D2 and - D3 ranges (Amplifex and RIA, pc = 0.97; Amplifex and PTAD, pc = 0.96) but less strongly on the lower levels of the standard range (Amplifex and RIA, pc = 0.81; Amplifex and PTAD, pc = 0.65) suggesting differences in the sensitivities between the assays. The Amplifex method was determined to be more sensitive than the PTAD method, as peak areas were significantly higher for the Amplifex method and provided for a 10 fold higher signal-to-noise ratio than PTAD. Therefore, the Amplifex LC/MS/MS method is the most sensitive and specific method available for measuring 1,25-(OH)2-D2 and -D3 while using the smallest sample volume. PMID:24576767

  5. Development of a sensitive LC/MS/MS method for vitamin D metabolites: 1,25 Dihydroxyvitamin D2&3 measurement using a novel derivatization agent.

    PubMed

    Hedman, Curtis J; Wiebe, Donald A; Dey, Subhakar; Plath, Josh; Kemnitz, Joseph W; Ziegler, Toni E

    2014-03-15

    Active vitamin D metabolites 1,25-dihydroxyvitamin D2 [1,25-(OH)2-D2; derived from ergocalciferol] and D3 [1,25-(OH)2-D3; derived from cholecalciferol] are found in low levels in the circulation and require a very sensitive method for measurement. Radioimmunoassay (RIA) has been the method of choice, but it lacks the specificity needed to distinguish between 1,25-(OH)2-D2 and -D3, whereas liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods have the advantage of high specificity and sensitivity. Here, we compare a new derivative for ionizing 1,25-(OH)2-D to enhance the signal and provide the most sensitive assay for measuring vitamin D. We used the Amplifex diene method of derivatizing prior to LC/MS/MS and compared it to the standard RIA method and the 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) method of derivatizing prior to LC/MS/MS. In the evaluation of 20 human serum samples, all methods correlated strongly across the upper levels of the standard 1,25-(OH)2-D2 and -D3 ranges (Amplifex and RIA, pc=0.97; Amplifex and PTAD, pc=0.96) but less strongly on the lower levels of the standard range (Amplifex and RIA, pc=0.81; Amplifex and PTAD, pc=0.65) suggesting differences in the sensitivities between the assays. The Amplifex method was determined to be more sensitive than the PTAD method, as peak areas were significantly higher for the Amplifex method and provided for a 10 fold higher signal-to-noise ratio than PTAD. Therefore, the Amplifex LC/MS/MS method is the most sensitive and specific method available for measuring 1,25-(OH)2-D2 and -D3 while using the smallest sample volume.

  6. Caveolae and caveolin-1 are implicated in 1alpha,25(OH)2-vitamin D3-dependent modulation of Src, MAPK cascades and VDR localization in skeletal muscle cells.

    PubMed

    Buitrago, Claudia; Boland, Ricardo

    2010-07-01

    We previously reported that 1alpha,25(OH)2D3 induces non-transcriptional rapid responses through activation of MAPKs in C2C12 skeletal muscle cells. However, there is little information on the molecular mechanism underlying the initiation of 1alpha,25(OH)2D3 signaling through this pathway. Plasma membrane components have been involved in some non-genomic effects. In this work, we investigated the role of caveolae and caveolin-1 (cav-1) in 1alpha,25(OH)2D3-stimulation of c-Src and MAPKs. When proliferating cells were pretreated with methyl beta cyclodextrin (MbetaCD), a caveolae disrupting agent, under conditions in which cell morphology is not affected and no signs of apoptosis are observed, 1alpha,25(OH)2D3-dependent activation of ERK1/2, p38 MAPK and c-Src was suppressed. Similar results were obtained by siRNA technology whereby silencing of cav-1 expression abolished activation of c-Src and MAPKs induced by the hormone. By confocal immunocytochemistry it was observed that cav-1 colocalizes with c-Src in the periplasma membrane zone at basal conditions. Hormone treatment disrupted the colocalization of these proteins and redistributed them into cytoplasm and nucleus. Co-immunoprecipitation assays corroborated these observations. Changes in VDR localization after 1alpha,25(OH)2D3 exposure were also investigated. Confocal microscopy images showed that the hormone induces VDR translocation to the plasma membrane, and this effect is abolished by MbetaCD. Altogether, these data suggest that caveolae is involved upstream in c-Src-MAPKs activation by 1alpha,25(OH)2D3 and that VDR and cav-1 participate in the rapid signaling elicited by the hormone.

  7. MAP kinases p38 and JNK are activated by the steroid hormone 1alpha,25(OH)2-vitamin D3 in the C2C12 muscle cell line.

    PubMed

    Buitrago, Claudia G; Ronda, Ana C; de Boland, Ana Russo; Boland, Ricardo

    2006-03-01

    In chick skeletal muscle cell primary cultures, we previously demonstrated that 1alpha,25(OH)2-vitamin D3 [1alpha,25(OH)2D3], the hormonally active form of vitamin D, increases the phosphorylation and activity of the extracellular signal-regulated mitogen-activated protein (MAP) kinase isoforms ERK1 and ERK2, their subsequent translocation to the nucleus and involvement in DNA synthesis stimulation. In this study, we show that other members of the MAP kinase superfamily are also activated by the hormone. Using the muscle cell line C2C12 we found that 1alpha,25(OH)2D3 within 1 min phosphorylates and increases the activity of p38 MAPK. The immediately upstream mitogen-activated protein kinase kinases 3/6 (MKK3/MKK6) were also phosphorylated by the hormone suggesting their participation in p38 activation. 1Alpha,25(OH)2D3 was able to dephosphorylate/activate the ubiquitous cytosolic tyrosine kinase c-Src in C2C12 cells and studies with specific inhibitors imply that Src participates in hormone induced-p38 activation. Of relevance, 1alpha,25(OH)2D3 induced in the C2C12 line the stimulation of mitogen-activated protein kinase activating protein kinase 2 (MAPKAP-kinase 2) and subsequent phosphorylation of heat shock protein 27 (HSP27) in a p38 kinase activation-dependent manner. Treatment with the p38 inhibitor, SB203580, blocked p38 phosphorylation caused by the hormone and inhibited the phosphorylation of its downstrean substrates. 1Alpha,25(OH)2D3 also promotes the phosphorylation of c-jun N-terminal protein kinases (JNK 1/2), the response is fast (0.5-1 min) and maximal phosphorylation of the enzyme is observed at physiological doses of 1alpha,25(OH)2D3 (1 nM). The relative contribution of ERK-1/2, p38, and JNK-1/2 and their interrelationships in hormonal regulation of muscle cell proliferation and differentiation remain to be established.

  8. 25(OH)D Is Effective to Repress Human Cholangiocarcinoma Cell Growth through the Conversion of 25(OH)D to 1α,25(OH)2D3

    PubMed Central

    Chiang, Kun-Chun; Yeh, Chun-Nan; Huang, Cheng-Cheng; Yeh, Ta-Sen; S. Pang, Jong-Hwei; Hsu, Jun-Te; Chen, Li-Wei; Kuo, Sheng-Fong; Kittaka, Atsushi; Chen, Tai C.; Juang, Horng-Heng

    2016-01-01

    Cholangiocarcinoma (CCA) is a devastating disease without effective treatments. 1α,25(OH)2D3, the active form of Vitamin D, has emerged as a new anti-cancer regimen. However, the side effect of hypercalcemia impedes its systemic administration. 25(OH)D is biologically inert and needs hydroxylation by CYP27B1 to form 1α,25(OH)2D3, which is originally believed to only take place in kidneys. Recently, the extra-renal expression of CYP27B1 has been identified and in vitro conversion of 25(OH)D to 1α,25(OH)2D3 has been found in some cancer cells with CYP27B1 expression. In this study, CYP27B1 expression was demonstrated in CCA cells and human CCA specimens. 25(OH)D effectively represses SNU308 cells growth, which was strengthened or attenuated as CYP27B1 overexpression or knockdown. Lipocalcin-2 (LCN2) was also found to be repressed by 25(OH)D. After treatment with 800 ng/mL 25(OH)D, the intracellular 1α,25(OH)2D3 concentration was higher in SNU308 cells with CYP27B1 overexpression than wild type SNU308 cells. In a xenograft animal experiment, 25(OH)D, at a dose of 6 μg/kg or 20 μg/kg, significantly inhibited SNU308 cells’ growth without inducing obvious side effects. Collectively, our results indicated that SNU308 cells were able to convert 25(OH)D to 1α,25(OH)2D3 and 25(OH)D CYP27B1 gene therapy could be deemed as a promising therapeutic direction for CCA. PMID:27529229

  9. Exogenous versus endogenous recovery of 25-hydroxyvitamins D2 and D3 in human samples using high-performance liquid chromatography and the DiaSorin LIAISON Total-D Assay.

    PubMed

    Horst, Ronald L

    2010-07-01

    Demand for circulating 25-hydroxyvitamin D [25(OH)D] measurements has exploded due to its relationship with many serious health problems. The present study was designed to investigate the validity of samples "spiked" with 25-hydroxyvitamin D2 [25(OH)D2] or 25-hydroxyvitamin D3 [25(OH)D3] to determine their analytical recovery by the DiaSorin LIAISON 25 OH Vitamin D Total Assay (DiaSorin Assay) and high-performance liquid chromatography (HPLC). 25(OH)D was measured in nine volunteers taking large daily doses of vitamin D2 for 2 weeks. Samples were obtained pre-supplementation and 1 week following vitamin D2. Pre-supplementation samples were used for exogenous recovery studies by adding 25(OH)D2 or 25(OH)D3. Endogenous 25(OH)D [25(OH)D2 plus 25(OH)D3] concentrations reported by the DiaSorin Assay or detected by HPLC were in excellent agreement. However, exogenously added 25(OH)D2 and 25(OH)D3 were under-recovered by the DiaSorin Assay. NIST vitamin D standards containing serum from another species (horse) or exogenous 25(OH)D2 were similarly affected when using the DiaSorin Assay. Exogenous 25(OH)D2, 25(OH)D3 or serum from other species added to human samples is inappropriate in determining the analytical recovery of vitamin D compounds when using the DiaSorin Assay. Only endogenous 25(OH)D2 and/or 25(OH)D3 contained in human blood samples should be utilized for this purpose.

  10. Short-term bisphosphonate treatment reduces serum 25(OH) vitamin D3 and alters values of parathyroid hormone, pentosidine, and bone metabolic markers

    PubMed Central

    Kamimura, Mikio; Uchiyama, Shigeharu; Nakamura, Yukio; Ikegami, Shota; Mukaiyama, Keijiro; Kato, Hiroyuki

    2017-01-01

    This study aimed to clarify the effects of short-term bisphosphonate (BP) administration in Japanese osteoporotic patients retrospectively. Daily minodronate (MIN) at 1 mg/day (MIN group) or weekly risedronate (RIS) at 17.5 mg/week (RIS group) was primarily prescribed for each patient. We analyzed the laboratory data of 35 cases (18 of MIN and 17 of RIS) before the start of treatment and at 4 months afterward. The changes in 25(OH)D3, whole parathyroid hormone (PTH), serum pentosidine, and the bone turnover markers urinary cross-linked N-telopeptide of type I collagen (NTX), serum tartrate-resistant acid phosphatase (TRACP)-5b, bone-specific alkaline phosphatase (BAP), and undercarboxylated osteocalcin were evaluated. Overall, serum 25(OH)D3 was significantly decreased from 21.8 to 18.4 ng/mL at 4 months, with a percent change of −14.7%. Whole PTH increased significantly from 23.4 to 30.0 pg/mL, with a percent change of 32.1%. Serum pentosidine rose from 0.0306 to 0.0337 μg/mL, with a percent change of 15.2%. In group comparisons, 25(OH)D3 and pentosidine showed comparable changes in both groups after 4 months of treatment, whereas whole PTH became significantly more increased in the MIN group. All bone turnover markers were significantly decreased at 4 months in both groups. Compared with the RIS group, the MIN group exhibited significantly larger value changes for urinary NTX, serum TRACP-5b, and BAP at the study end point. This study demonstrated that serum 25(OH)D3 became significantly decreased after only 4 months of BP treatment in Japanese osteoporotic patients and confirmed that MIN more strongly inhibited bone turnover as compared with RIS. PMID:28243105

  11. Effect of 12-Week Vitamin D Supplementation on 25[OH]D Status and Performance in Athletes with a Spinal Cord Injury.

    PubMed

    Flueck, Joelle Leonie; Schlaepfer, Max Walter; Perret, Claudio

    2016-09-22

    (1) BACKGROUND: studies with able-bodied athletes showed that performance might possibly be influenced by vitamin D status. Vitamin D seems to have a direct impact on neuromuscular function by docking on vitamin D receptors in the muscle tissue. Additionally, a high prevalence of vitamin D deficiency was shown not only in infants and in the elderly but also in healthy adults and spinal cord injured individuals. Therefore, the aim of our study was to investigate whether a vitamin D dose of 6000 IU daily over 12 weeks would be sufficient to increase vitamin D status in indoor wheelchair athletes to a normal or optimal vitamin D level and whether vitamin D deficiency is associated with an impairment in muscle performance in these individuals; (2) METHODS: vitamin D status was assessed in indoor elite wheelchair athletes in order to have a baseline measurement. If vitamin D status was below 75 nmol/L, athletes were supplemented with 6000 IU of vitamin D daily over 12 weeks. A vitamin D status over 75 nmol/L was supplemented with a placebo supplement. Vitamin D status, as well as a Wingate test and an isokinetic dynamometer test, were performed at baseline and after six and 12 weeks; (3) RESULTS: 20 indoor elite wheelchair athletes participated in this double-blind study. All of these athletes showed an insufficient vitamin D status at baseline and were, therefore, supplemented with vitamin D. All athletes increased vitamin D status significantly over 12 weeks and reached an optimal level. Wingate performance was not significantly increased. Isokinetic dynamometer strength was significantly increased but only in the non-dominant arm in isometric and concentric elbow flexion; (4) CONCLUSION: a dose of 6000 IU of vitamin D daily over a duration of 12 weeks seems to be sufficient to increase vitamin D status to an optimal level in indoor wheelchair athletes. It remains unclear, whether upper body performance or muscle strength and vitamin D status are associated with each

  12. [Assay of fat-soluble vitamins--vitamin D].

    PubMed

    Kobayashi, T

    1993-04-01

    Methods for determination of vitamin D, 25-OH-D, 24,25(OH)2D and 1,25(OH)2D in plasma are reviewed. A method for simultaneous determination of the D2 and D3 compounds of vitamin D and the metabolites in plasma is established. The method includes extraction of lipid, followed by three steps of HPLC for clean-up and separation. Vitamin D and 25-OH-D are quantified by HPLC with a UV detector, while 24,25(OH)2D and 1,25(OH)2D are assayed by CPBA and RRA methods, respectively. The assayed values for concentrations of the compounds in plasma of normal subjects and various kinds of patients are shown. A simplified method for assaying 1,25(OH)2D in plasma using calf thymus receptor is also introduced.

  13. Effect of 12-Week Vitamin D Supplementation on 25[OH]D Status and Performance in Athletes with a Spinal Cord Injury

    PubMed Central

    Flueck, Joelle Leonie; Schlaepfer, Max Walter; Perret, Claudio

    2016-01-01

    (1) Background: studies with able-bodied athletes showed that performance might possibly be influenced by vitamin D status. Vitamin D seems to have a direct impact on neuromuscular function by docking on vitamin D receptors in the muscle tissue. Additionally, a high prevalence of vitamin D deficiency was shown not only in infants and in the elderly but also in healthy adults and spinal cord injured individuals. Therefore, the aim of our study was to investigate whether a vitamin D dose of 6000 IU daily over 12 weeks would be sufficient to increase vitamin D status in indoor wheelchair athletes to a normal or optimal vitamin D level and whether vitamin D deficiency is associated with an impairment in muscle performance in these individuals; (2) Methods: vitamin D status was assessed in indoor elite wheelchair athletes in order to have a baseline measurement. If vitamin D status was below 75 nmol/L, athletes were supplemented with 6000 IU of vitamin D daily over 12 weeks. A vitamin D status over 75 nmol/L was supplemented with a placebo supplement. Vitamin D status, as well as a Wingate test and an isokinetic dynamometer test, were performed at baseline and after six and 12 weeks; (3) Results: 20 indoor elite wheelchair athletes participated in this double-blind study. All of these athletes showed an insufficient vitamin D status at baseline and were, therefore, supplemented with vitamin D. All athletes increased vitamin D status significantly over 12 weeks and reached an optimal level. Wingate performance was not significantly increased. Isokinetic dynamometer strength was significantly increased but only in the non-dominant arm in isometric and concentric elbow flexion; (4) Conclusion: a dose of 6000 IU of vitamin D daily over a duration of 12 weeks seems to be sufficient to increase vitamin D status to an optimal level in indoor wheelchair athletes. It remains unclear, whether upper body performance or muscle strength and vitamin D status are associated with each

  14. Vitamin D2, Ergosterol, and Vitamin B2 Content in Commercially Dried Mushrooms Marketed in China and Increased Vitamin D2 Content Following UV-C Irradiation.

    PubMed

    Huang, Guocheng; Cai, Weixi; Xu, Baojun

    2016-11-21

    Mushrooms are a great source of vitamin D and vitamin B2; however, the content of these vitamins in dried mushrooms has not fully been investigated. Thus, the objectives of this study were to determine the contents of vitamin D2, ergosterol, and vitamin B2 in commercially dried edible mushrooms in China and to investigate the effect of UV-C irradiation on fresh mushrooms. Among the 35 species of dried mushrooms considered for this study, the average ergosterol content was 1.98 mg/g, while the average vitamin D2 content was 16.88 µg/g. The average vitamin B2 content in dried mushrooms was 12.68 µg/g. Fresh shaggy ink caps and oyster mushrooms, when exposed to UV-C at 254 nm at a dose of 0.25 J/cm(2) for 10, 30, and 60 min, showed significantly (p < 0.05) increased vitamin D2 content (229.7 and 67.0 µg/g, respectively) as compared to its fresh counterparts. The conversion of ergosterol to vitamin D2 induced by UV-C irradiation at 0.25 J/cm(2) was significant (p < 0.05). In conclusion, dried commercial mushrooms have higher contents of ergosterol and vitamin D2 than fresh mushrooms. UV-C radiation can be used to increase vitamin D2 content in mushrooms.

  15. Free 25(OH)D and Calcium Absorption, PTH, and Markers of Bone Turnover

    PubMed Central

    Dhaliwal, Ruban; Mikhail, Mageda; Shieh, Albert; Stolberg, Alexandra; Ragolia, Louis; Fazzari, Melissa; Abrams, Steven A.

    2015-01-01

    Context: It has been proposed that serum free 25-hydroxyvitamin D [25(OH)D] may better reflect vitamin D action than total 25(OH)D. An ELISA for serum free 25(OH)D has recently become available, permitting direct assay. Objective: To determine whether serum free 25(OH)D provides additional information in relation to calcium absorption and other biomarkers of vitamin D action compared to total serum 25(OH)D. Setting: Ambulatory research setting in a teaching hospital. Outcome: Serum free 25(OH)D measured in a previously performed study of varied doses of vitamin D3 (placebo and 800, 2000, and 4000 IU) on calcium absorption, PTH, procollagen type 1 N-terminal propeptide, and C-terminal telopeptides of type I collagen. Free 25(OH)D was measured by ELISA. Calcium absorption was measured at baseline and at 10 weeks using stable dual calcium isotopes. Results: Seventy-one subjects completed this randomized, placebo-controlled trial. Baseline group mean free and total 25(OH)D varied from 4.7 ± 1.8 to 5.4 ± 1.5 pg/mL, and from 23.7 ± 5.9 to 25.9 ± 6.1 ng/mL, respectively. Participants assigned to the 4000-IU dose arm achieved free 25(OH)D levels of 10.4 pg/mL and total 25(OH)D levels of 40.4 ng/mL. Total and free 25(OH)D were highly correlated at baseline and after increasing vitamin D dosing (r = 0.80 and 0.85, respectively). Free 25(OH)D closely reflected changes in total 25(OH)D. PTH was similarly correlated at baseline and follow-up with total and free 25(OH)D. Serum C-terminal telopeptides of type I collagen had a moderate positive correlation with total and free 25(OH)D at follow-up. The serum 1,25-dihydroxyvitamin D change increased significantly with the change in 25(OH)D but not with the change in free 25(OH)D. Conclusion: There was no advantage from measuring free over total 25(OH)D in assessing the response of calcium absorption, PTH, and markers of bone turnover to vitamin D. Free 25(OH)D responded to increasing doses of vitamin D in a similar fashion to

  16. Effects of 1,25(OH)2D3 and 25(OH)D3 on C2C12 Myoblast Proliferation, Differentiation, and Myotube Hypertrophy

    PubMed Central

    van der Meijden, K.; Bravenboer, N.; Dirks, N.F.; Heijboer, A.C.; den Heijer, M.; de Wit, G.M.J.; Offringa, C.; Lips, P.

    2016-01-01

    An adequate vitamin D status is essential to optimize muscle strength. However, whether vitamin D directly reduces muscle fiber atrophy or stimulates muscle fiber hypertrophy remains subject of debate. A mechanism that may affect the role of vitamin D in the regulation of muscle fiber size is the local conversion of 25(OH)D to 1,25(OH)2D by 1α‐hydroxylase. Therefore, we investigated in a murine C2C12 myoblast culture whether both 1,25(OH)2D3 and 25(OH)D3 affect myoblast proliferation, differentiation, and myotube size and whether these cells are able to metabolize 25(OH)D3 and 1,25(OH)2D3. We show that myoblasts not only responded to 1,25(OH)2D3, but also to the precursor 25(OH)D3 by increasing their VDR mRNA expression and reducing their proliferation. In differentiating myoblasts and myotubes 1,25(OH)2D3 as well as 25(OH)D3 stimulated VDR mRNA expression and in myotubes 1,25(OH)2D3 also stimulated MHC mRNA expression. However, this occurred without notable effects on myotube size. Moreover, no effects on the Akt/mTOR signaling pathway as well as MyoD and myogenin mRNA levels were observed. Interestingly, both myoblasts and myotubes expressed CYP27B1 and CYP24 mRNA which are required for vitamin D3 metabolism. Although 1α‐hydroxylase activity could not be shown in myotubes, after treatment with 1,25(OH)2D3 or 25(OH)D3 myotubes showed strongly elevated CYP24 mRNA levels compared to untreated cells. Moreover, myotubes were able to convert 25(OH)D3 to 24R,25(OH)2D3 which may play a role in myoblast proliferation and differentiation. These data suggest that skeletal muscle is not only a direct target for vitamin D3 metabolites, but is also able to metabolize 25(OH)D3 and 1,25(OH)2D3. J. Cell. Physiol. 231: 2517–2528, 2016. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc. PMID:27018098

  17. Determination of mono- and dihydroxy-vitamin D metabolites in normal subjects and patients with different calcium metabolic diseases.

    PubMed

    Hummer, L; Riis, B J; Christiansen, C; Rickers, H

    1985-11-01

    Reliable assays to determine the vitamin D metabolites are useful aids in the study of disorders involving vitamin D metabolism, and in the evaluation of the response in patients receiving vitamin D treatment. We report here the establishment in our laboratory of a method capable of measuring 25(OH)D, (including 25(OH)D2 and 25(OH)D3), 1,25(OH)2D and 24,25(OH)2D in a single blood sample. The method involves methanol/dichloromethane extraction and Sephadex LH-20 chromatography. The monhydroxylated fraction was purified on Lipidex 5000 and separated in 25(OH)D2 and 25(OH)D3 on high pressure liquid chromatography (HPLC), followed by ultra violet absorbance (UV) detection. The dihydroxylated fraction was separated by HPLC and quantified by protein-binding assays. The method is precise and accurate. The vitamin D metabolites were measured in different groups of patients and in normal subjects.

  18. Plasma 25-hydroxyvitamin D2 and D3 levels and incidence of postoperative atrial fibrillation.

    PubMed

    Skuladottir, G V; Cohen, A; Arnar, D O; Hougaard, D M; Torfason, B; Palsson, R; Indridason, O S

    2016-01-01

    Low circulating levels of total 25-hydroxyvitamin D (25(OH)D) have been associated with an increased risk of adverse effects after cardiac surgery. The metabolites, 25(OH)D2 and 25(OH)D3, provide a good index of vitamin D status. In this study, we examined the association between preoperative plasma levels of total 25(OH)D, 25(OH)D2 and 25(OH)D3 and the risk of postoperative atrial fibrillation (POAF) following open heart surgery. The levels of plasma 25(OH)D2 and 25(OH)D3 in 118 patients, who underwent coronary artery bypass grafting and/or valvular surgery, were measured immediately prior to surgery and on postoperative day 3 by liquid chromatography-tandem mass spectrometry. Patients who developed POAF had higher median plasma levels of 25(OH)D2 than those who remained in sinus rhythm (SR) (P = 0·003), but no significant difference was noted in levels of 25(OH)D3 or total 25(OH)D between the two groups (P > 0·05). By univariate analysis, patients with total 25(OH)D and 25(OH)D2 levels above the median had higher frequency of POAF (P < 0·05) and the incidence of POAF increased significantly with each higher quartile of preoperative plasma levels of 25(OH)D2 (P = 0·001), an association that was independent of confounding factors. In both the SR and POAF groups, the median plasma levels of 25(OH)D2, 25(OH)D3 and total 25(OH)D were lower (P < 0·05) on the third postoperative day compared with preoperatively. Our findings demonstrate that higher plasma levels of 25(OH)D2 are associated with increased risk of POAF, while this is not the case for 25(OH)D3 or total 25(OH)D. The reason for these discrepant results is not clear but warrants further study.

  19. Insulin and body weight but not hyperandrogenism seem involved in seasonal serum 25-OH-vitamin D3 levels in subjects affected by PCOS.

    PubMed

    Gallea, Mariateresa; Granzotto, Marnie; Azzolini, Sara; Faggian, Diego; Mozzanega, Bruno; Vettor, Roberto; Mioni, Roberto

    2014-10-01

    PCOS patients were frequently characterized by lower plasma vitamin D levels. The mechanisms involved in this dysfunction remains still debated, therefore we evaluated the role of androgen, insulin and body weight on the serum VitD levels in women with or without PCOS. Eighty one patients 18-42 yrs old were studied into "SUMMER" and "WINTER" seasonal period: thirty seven PCOS, seventeen no-ovarian hyperandrogenic (noPCOS), twelve functional hypothalamic amenorrhea (FHA) and finally fifteen healthy (Con). Patients were further divided into: lean (L), obese (O), normo- (nINS) and hyperinsulinemic (hINS). All hormonal and metabolic parameters were measured at 1-7 days of the menstrual cycle. Our results show that VitD levels were lower in PCOS and in noPCOS than in FHA and Con, in particular in (O) and (hINS) PCOSs. Both in summer and in winter, PCOSs had basal VitD levels significantly lower than FHA and Con, whereas they were similar to noPCOS. Yet, LhINS and OPCOS had VitD levels lower than Con and noPCOS. VitD levels were comparable in LnINS PCOS and Con. In conclusion, PCOSs had levels of VitD lower than controls. Weight and hyperinsulinemia had a significant influence on these values. Finally, over 70% of our healthy patients had VitD deficiency.

  20. Treatment of 25-OH vitamin D deficiency in older men with chronic kidney disease stages 3 and 4 is associated with reduction in cardiovascular events.

    PubMed

    Lishmanov, Anton; Dorairajan, Smrita; Pak, Youngju; Chaudhary, Kunal; Chockalingam, Anand

    2013-01-01

    Observational studies in healthy people suggest an inverse relationship between serum 25-hydroxyvitamin D (25OHD) levels and cardiovascular (CV) mortality. Treating vitamin D deficiency in patients with moderate chronic kidney disease (CKD) may reduce CV events in this high-risk population. Study data were abstracted from Harry S. Truman Memorial Veterans Hospital electronic medical record system. The medical records of all veterans who had CKD stages 3 and 4 and had 25OHD levels determined from April 2006 to September 2007 were reviewed. Patients with 25OHD deficiency, serum level <30 ng/mL, were included (N = 126, all men, mean age = 70 years). Successful 25OHD replacement was defined as prescription of ergocalciferol sufficient to increase serum 25OHD level by 25% from baseline within 6 months (treatment group, n = 90). Otherwise patients were considered as untreated controls (n = 36). The date when the 25OHD level was drawn was considered as the date of inclusion. All the patients were followed up from the date of inclusion until July 2009 to capture CV events prospectively. During mean follow-up of 27.2 months, 44% of the controls had CV events, whereas only 21% of the patients in the treatment group had CV events (P = 0.001). In multivariate logistic regression analysis, adjusting for CV disease predictors age, initial parathyroid hormone level, statin use, history of CV disease, and glomerular filtration rate, the estimated odds ratio for 25OHD replacement status was 0.37 (95% confidence interval: 0.14-1.0). Treatment of 25OHD deficiency with ergocalciferol in patients with moderate CKD is associated with significant reduction in CV events.

  1. Vitamin D from different sources is inversely associated with Parkinson disease.

    PubMed

    Wang, Liyong; Evatt, Marian L; Maldonado, Lizmarie G; Perry, William R; Ritchie, James C; Beecham, Gary W; Martin, Eden R; Haines, Jonathan L; Pericak-Vance, Margaret A; Vance, Jeffery M; Scott, William K

    2015-04-01

    An inverse association between Parkinson disease (PD) and total vitamin D levels has been reported, but whether vitamin D from different sources, that is, 25(OH)D2 (from diet and supplements) and 25(OH)D3 (mainly from sunlight exposure), all contribute to the association is unknown. Plasma total 25(OH)D, 25(OH)D2, and 25(OH)D3 levels were measured by liquid chromatography-tandem mass spectrometry in PD patients (n = 478) and controls (n = 431). Total 25(OH)D was categorized by clinical insufficiency or deficiency; 25(OH)D2 and 25(OH)D3 were analyzed in quartiles. Vitamin D deficiency (total 25[OH]D < 20 ng/mL) and vitamin D insufficiency (total 25[OH]D < 30 ng/mL) are associated with PD risk (odds ratio [OR] = 2.6 [deficiency] and 2.1 [insufficiency]; P < 0.0001), adjusting for age, sex, and sampling season. Both 25(OH)D2 and 25(OH)D3 levels are inversely associated with PD (P(trend) < 0.0001). The association between 25(OH)D2 and PD risk is largely confined to individuals with low 25(OH)D3 levels (P(trend) = 0.0008 and 0.12 in individuals with 25[OH]D3 < 20 ng/mL and 25[OH]D3 ≥ 20 ng/mL, respectively). Our data confirm the association between vitamin D deficiency and PD, and for the first time demonstrate an inverse association of 25(OH)D2 with PD. Given that 25(OH)D2 concentration is independent of sunlight exposure, this new finding suggests that the inverse association between vitamin D levels and PD is not simply attributable to lack of sunlight exposure in PD patients with impaired mobility. The current study, however, cannot exclude the possibility that gastrointestinal dysfunction, a non-motor PD symptom, contributes to the lower vitamin D2 levels in PD patients.

  2. 1,25-(OH){sub 2}-vitamin D{sub 3} prevents activation of hepatic stellate cells in vitro and ameliorates inflammatory liver damage but not fibrosis in the Abcb4{sup −/−} model

    SciTech Connect

    Reiter, Florian P.; Hohenester, Simon; Nagel, Jutta M.; Wimmer, Ralf; Artmann, Renate; Wottke, Lena; Makeschin, Marie-Christine; Mayr, Doris; Rust, Christian; Trauner, Michael; Denk, Gerald U.

    2015-04-03

    Background/Purpose of the study: Vitamin D{sub 3}-deficiency is common in patients with chronic liver-disease and may promote disease progression. Vitamin D{sub 3}-administration has thus been proposed as a therapeutic approach. Vitamin D{sub 3} has immunomodulatory effects and may modulate autoimmune liver-disease such as primary sclerosing cholangitis. Although various mechanisms of action have been proposed, experimental evidence is limited. Here we test the hypothesis that active 1,25-(OH){sub 2}-vitamin D{sub 3} inhibits activation of hepatic stellate cells (HSC) in vitro and modulates liver-injury in vivo. Methods: Proliferation and activation of primary murine HSC were assessed by BrdU- and PicoGreen{sup ®}-assays, immunoblotting, immunofluorescence-microscopy, quantitative-PCR, and zymography following calcitriol-treatment. Wild-type and ATP-binding cassette transporter b4{sup −/−} (Abcb4{sup −/−})-mice received calcitriol for 4 weeks. Liver-damage, inflammation, and fibrosis were assessed by serum liver-tests, Sirius-red staining, quantitative-PCR, immunoblotting, immunohistochemistry and hydroxyproline quantification. Results: In vitro, calcitriol inhibited activation and proliferation of murine HSC as shown by reduced α-smooth muscle actin and platelet-derived growth factor-receptor-β-protein-levels, BrdU and PicoGreen®-assays. Furthermore, mRNA-levels and activity of matrix metalloproteinase 13 were profoundly increased. In vivo, calcitriol ameliorated inflammatory liver-injury reflected by reduced levels of alanine aminotransferase in Abcb4{sup −/−}-mice. In accordance, their livers had lower mRNA-levels of F4/80, tumor necrosis factor-receptor 1 and a lower count of portal CD11b positive cells. In contrast, no effect on overall fibrosis was observed. Conclusion: Calcitriol inhibits activation and proliferation of HSCs in vitro. In Abcb4{sup −/−}-mice, administration of calcitriol ameliorates inflammatory liver-damage but has

  3. Measurement of 25-hydroxyvitamin D2&3 and 1, 25-dihydroxyvitamin D2&3 by Tandem Mass Spectrometry: A Primate Multispecies Comparison

    PubMed Central

    Ziegler, Toni E.; Kapoor, Amita; Hedman, Curtis J.; Binkley, Neil; Kemnitz, Joseph W.

    2015-01-01

    Vitamin D metabolites are widely studied for their roles in bone health, immune functions and other potential physiologic roles in humans. However, the optimal blood levels of vitamin D metabolites are still unclear. Various methods for measuring vitamin D metabolites have been used and recently liquid chromatography tandem mass spectroscopy (LC-MS/MS) has been adopted as the gold standard for vitamin D metabolite measurement. Here we report the use of LC-MS/MS to measure 25-hydroxyvitamin D (25(OH)D2&3), and 1,25-dihydroxyvitamin D (1,25(OH)2D2&3), in three laboratory nonhuman primate species: common marmoset (Callithrix jacchus), rhesus macaque (Macaca mulatta), and cynomolgus macaque (Macaca fascicularis), and compare them to humans using the same technique. The nonhuman primates showed blood levels for 25(OH)D3 and 1,25(OH)2D3 significantly higher than human values with marmosets having the highest levels. Marmoset samples showed significantly more variability among individuals than those from macaques for both metabolites, but all three nonhuman primate species exhibited large variation within species for both 25(OH)D2&3 and 1,25(OH)2D2&3. Marmoset females had significantly lower values than the males for 25(OH)D3, while rhesus males showed a significant decrease in 25(OH)D3 with age. The most striking finding is the variation within species for vitamin D levels even in laboratory primates that have a controlled diet, UV exposure, and in some cases, genetic constraints. Similar variation in 25(OH)D responses to a fixed dose of oral vitamin D supplementation has been reported in humans. We suggest that these species can provide primate models for examining the factors influencing variation in the levels of vitamin D necessary for human and nonhuman primate health. PMID:25845705

  4. Investigating causality in the association between 25(OH)D and schizophrenia

    PubMed Central

    Taylor, Amy E.; Burgess, Stephen; Ware, Jennifer J.; Gage, Suzanne H.; Richards, J. Brent; Davey Smith, George; Munafò, Marcus R.

    2016-01-01

    Vitamin D deficiency is associated with increased risk of schizophrenia. However, it is not known whether this association is causal or what the direction of causality is. We performed two sample bidirectional Mendelian randomization analysis using single nucleotide polymorphisms (SNPs) robustly associated with serum 25(OH)D to investigate the causal effect of 25(OH)D on risk of schizophrenia, and SNPs robustly associated with schizophrenia to investigate the causal effect of schizophrenia on 25(OH)D. We used summary data from genome-wide association studies and meta-analyses of schizophrenia and 25(OH)D to obtain betas and standard errors for the SNP-exposure and SNP-outcome associations. These were combined using inverse variance weighted fixed effects meta-analyses. In 34,241 schizophrenia cases and 45,604 controls, there was no clear evidence for a causal effect of 25(OH)D on schizophrenia risk. The odds ratio for schizophrenia per 10% increase in 25(OH)D conferred by the four 25(OH)D increasing SNPs was 0.992 (95% CI: 0.969 to 1.015). In up to 16,125 individuals with measured serum 25(OH)D, there was no clear evidence that genetic risk for schizophrenia causally lowers serum 25(OH)D. These findings suggest that associations between schizophrenia and serum 25(OH)D may not be causal. Therefore, vitamin D supplementation may not prevent schizophrenia. PMID:27215954

  5. Mechanical loading and the synthesis of 1,25(OH)2D in primary human osteoblasts.

    PubMed

    van der Meijden, K; Bakker, A D; van Essen, H W; Heijboer, A C; Schulten, E A J M; Lips, P; Bravenboer, N

    2016-02-01

    local vitamin D metabolism in primary human osteoblasts. Our results suggest that 1,25(OH)2D3 and mechanical loading, both stimuli of the differentiation of osteoblasts, interact at the cellular level.

  6. 25(OH)D status: Effect of D3 supplement

    PubMed Central

    Luebbers, P. E.

    2017-01-01

    Summary Background Excess adipose tissue may lead to sequestrating of vitamin D, making it less available for use in the body. Objective This study determined if overweight or obese individuals (BMI > 25 kg m−2) had insufficient (<30 ng mL−1) levels of 25‐hydroxyvitamin D [25(OH)D] and, if so, would serum levels respond to exogenous supplementation. Methods Sixty‐three women who were overweight/obese (BMI = 31.07 ± 5.00 kg m−2) were randomly assigned in a double‐blind manner to receive 5,000 IU of vitamin D3 (D3) (n = 31) or a placebo (PL) (n = 32) daily. Serum 25(OH)D concentrations were measured by finger‐stick analyses at baseline and after 8 weeks of supplementation. Data were analyzed by using a 2 × 2 (group × time) repeated measure multivariate analysis of variance to determine group differences for pre‐values and post‐values (p < 0.05). Results On day one of the study, both D3 and PL groups had insufficient levels of vitamin D (mean ± SD) 24.03 ± 9.78 ng mL−1 and 23.62 ± 9.77 ng mL−1, respectively. After 8 weeks of supplementation, the D3 group 25(OH)D level rose to a mean of 43.57 ± 10.87 ng mL−1 (p < 0.001) versus the PL group whose 25(OH)D level remained statistically unchanged 24.31 ± 8.84 ng mL−1. Women who were overweight/obese had insufficient vitamin D levels prior to supplementation. Conclusions Following supplementation with 5,000 IU of vitamin D3, all subjects' 25(OH)D levels rose to a sufficient level (≥30 ng mL−1). The findings of this study concur with the Institute of Medicine and Endocrine Society recommendations in that two to three times the daily requirement of vitamin D is required to improve serum vitamin D levels in individuals who are overweight or obese. PMID:28392936

  7. Quantification of vitamin D and 25-hydroxyvitamin D in soft tissues by liquid chromatography-tandem mass spectrometry.

    PubMed

    Lipkie, Tristan E; Janasch, Amber; Cooper, Bruce R; Hohman, Emily E; Weaver, Connie M; Ferruzzi, Mario G

    2013-08-01

    Inadequate data on tissue distribution of vitamin D and its metabolites remains a barrier to defining health outcomes of vitamin D intake and 25-hydroxyvitamin D (25(OH)D) status. The purpose of this study was to develop a method for the analysis of vitamin D2 (ergocalciferol), vitamin D3 (cholecalciferol), 25(OH)D2, and 25(OH)D3 in soft tissues, and determine distribution in select tissues from a dose-response study of vitamin D2 and vitamin D3 in rats. Liver, gastrocnemius muscle, and epididymal fat homogenates were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with electrospray ionization following liquid-liquid extraction, solid-phase extraction, and derivatization with 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD). A dose-response was observed in most tissues for vitamin D and 25(OH)D from both vitamers. Vitamin D concentration was greater in epididymal fat than gastrocnemius muscle and liver, but 25(OH)D concentration was not significantly different between tissues. Soft tissues of rats fed crystalline vitamin D3 had higher concentrations of total vitamin D than those of rats fed yeast-derived vitamin D2, while total 25(OH)D concentrations were similar between vitamin D sources. This method is well suited to more complete studies of vitamin D bioavailability and metabolite tissue distribution.

  8. Quantification of vitamin D and 25-hydroxyvitamin D in soft tissues by liquid chromatography—tandem mass spectrometry

    PubMed Central

    Lipkie, Tristan E.; Janasch, Amber; Cooper, Bruce R.; Hohman, Emily E.; Weaver, Connie M.; Ferruzzi, Mario G.

    2013-01-01

    Inadequate data on tissue distribution of vitamin D and its metabolites remains a barrier to defining health outcomes of vitamin D intake and 25-hydroxyvitamin D (25(OH)D) status. The purpose of this study was to develop a method for the analysis of vitamin D2 (ergocalciferol), vitamin D3 (cholecalciferol), 25(OH)D2, and 25(OH)D3 in soft tissues, and determine distribution in select tissues from a dose-response study of vitamin D2 and vitamin D3 in rats. Liver, gastrocnemius muscle, and epididymal fat homogenates were analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) with electrospray ionization following liquid-liquid extraction, solid-phase extraction, and derivatization with 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD). A dose-response was observed in most tissues for vitamin D and 25(OH)D from both vitamers. Vitamin D concentration was greater in epididymal fat than gastrocnemius muscle and liver, but 25(OH)D concentration was not significantly different between tissues. Soft tissues of rats fed crystalline vitamin D3 had higher concentrations of total vitamin D than those of rats fed yeast-derived vitamin D2, while total 25(OH)D concentrations were similar between vitamin D sources. This method is well suited to more complete studies of vitamin D bioavailability and metabolite tissue distribution. PMID:23811497

  9. Different effect of vitamin D2 and vitamin D3 on amyloid-β40 aggregation in vitro.

    PubMed

    Suenaga, Midori; Takahashi, Hironobu; Imagawa, Hiroshi; Wagatsuma, Michiru; Ouma, Shinji; Tsuboi, Yoshio; Furuta, Akiko; Matsunaga, Yoichi

    2014-01-01

    The seeding of amyloid-β 40 (Aβ40) oligomers from monomers is the initial step of Aβ aggregation, and many reports have suggested that cholesterol enhances this step. We studied the potential of secosteroid vitamin D derivatives for Aβ40 aggregation in vitro. The quartz-crystal microbalance technique demonstrated that vitamin D3 does not show any effect on Aβ40 aggregation while vitamin D2 promoted it and docking simulation but that vitamin D2 has high potential in this regard. Thus, stacking of the Phe19 benzene ring in Aβ40 and the C22-C23 double bond in vitamin D2 may alter the energy of these molecules. Electron microscopy revealed the potential of vitamin D2 to increase Aβ40 aggregation. Thioflavin-T assays indicated that Vitamin D2 induced increased fluorescence at 490 nm, as typically observed for amyloid fibrils but also for protofibrils; in both cases this reflects of the increase of β-sheet contents. Aβ40 aggregation was further confirmed in ELISA, SDS-PAGE and dot blot analysis which revealed changes in protease K resistance. These results suggest a possible mechanism, of how vitamin D2 could increase Aβ40 aggregation and the docking simulation explains, why the same is not observed with vitamin D3.

  10. 25-Hydroxyvitamin D Can Interfere With a Common Assay for 1,25-Dihydroxyvitamin D in Vitamin D Intoxication

    PubMed Central

    Hawkes, Colin P.; Schnellbacher, Sarah; Singh, Ravinder J.

    2015-01-01

    Context: Vitamin D intoxication is characterized by elevated serum 25-hydroxyvitamin D (25(OH)D) and suppressed serum 1,25-dihydroxvitamin D (1,25(OH)2D). We evaluated two adolescents with hypercalcemia due to vitamin D intoxication; both had elevated serum 1,25(OH)2D by Diasorin RIA, but normal serum 1,25(OH)2D concentrations by liquid chromatography–tandem mass spectrometry (LC-MS/MS). Objective: This study aimed to determine the effect of 25(OH)D2 and 25(OH)D3 on 1,25(OH)2D concentration determined using RIA and LC-MS/MS. Methods: Pools of normal serum and an artificial serum matrix were prepared and aliquots were spiked with >99% pure 25(OH)D2 or 25(OH)D3 (50–700 ng/mL). Samples were maintained at 4°C or heated to 56°C, and the concentrations of vitamin D metabolites were measured by LC-MS/MS and Diasorin RIA. Results: Median 1,25(OH)2D increased by 114% with RIA and 21% with LC-MS/MS with addition of 100 ng/mL 25(OH)D3, and 349% (RIA) and 117% (LC-MS/MS) with 700 ng/mL of 25(OH)D3. Each 1-ng/mL increase in 25(OH)D3 increased 1,25(OH)2D by 0.231 pg/mL (RIA) and 0.121 pg/mL (LC-MS/MS). Spiking with 25(OH)D2 led to similar changes. Heat inactivation of serum, and using an artificial serum matrix, were associated with similar effects of 25(OH)D on 1,25(OH)2D assays. Conclusions: Vitamin D intoxication with high serum levels of 25(OH)D2 or 25(OH)D3 can be associated with elevated levels of 1,25(OH)2D due to interference in a commonly used RIA. A similar but attenuated effect also occurs when 1,25(OH)2D is measured using LC-MS/MS but does not seem to be clinically significant. The basis for this effect on the LC-MS/MS assay is presently uncertain. PMID:26120794

  11. Plasma profile of hydroxylated vitamin D metabolites: methods and results in normals for spring-winter in Southern Finland.

    PubMed

    Dabek, J T

    1980-02-01

    The spring-winter plasma concentrations of the hydroxylated metabolites of vitamin D have been measured in normal human subjects (20 male, 13 female), using high pressure liquid chromatography with UV-detection for 25-hydroxy vitamin D3/D2 (25(OH)D) and 24,25-dihydroxy vitamin D3/D2 (24,25(OH)2D) and a radioligand receptor assay for 1,25-dihydroxy vitamin D3/D2 (1,25-(OH)2D). The respective levels were 26.6 +/- 16 nmol . l-1, 2.24 +/- 1.3 nmol . l-1 and 114 +/- 35 pmol . l-1. These are in good agreement with levels from other centres for the same season. There was a significant negative correlation between 24,25(OH)2D and 1,25(OH)2 levels. The possible significance of this in the context of the low post-winter body burden of vitamin D is discussed. There was a positive correlation between 25(OH)D and 24,25(OH)2D levels but it did not reach statistical significance. There were no statistically significant differences between the levels of the hydroxylated metabolites in men and women but the 24,25(OH)2D levels were generally lower in the women. The 1,25(OH)2D levels were similar to those measured by isotope dilution mass fragmentography on Norwegian donor blood.

  12. Low bioaccessibility of vitamin D2 from yeast-fortified bread compared to crystalline D2 bread and D3 from fluid milks.

    PubMed

    Lipkie, Tristan E; Ferruzzi, Mario G; Weaver, Connie M

    2016-11-09

    The assessment of the efficacy of dietary and supplemental vitamin D tends to be confounded by differences in the serum 25-hydroxyvitamin D response between vitamin D2 and vitamin D3. Serum response differences from these vitamers may be due to differences in bioavailability. To address this specifically, the bioaccessibility was assessed for vitamin D2 from breads fortified with UV-treated yeast, and a benchmark against staple vitamin D3 fortified foods including bovine milks and infant formula, as well as crystalline vitamin D2 fortified bread. Fortified foods were subjected to a three-stage static in vitro digestion model, and vitamin D was analyzed by HPLC-MS. Vitamin D bioaccessibility was significantly greater from bovine milks and infant formula (71-85%) than from yeast-fortified sandwich breads (6-7%). Bioaccessibility was not different between whole wheat and white wheat bread (p > 0.05), but was ∼4× lower from yeast-fortified bread than from crystalline vitamin D2 fortified bread (p < 0.05). Intact yeast cells were observed in the digesta of yeast fortified bread. These results indicate that the low bioavailability of yeast D2 in comparison to other vitamin D2 sources is likely due to entrapment within a less digestible yeast matrix and not only to metabolic differences between vitamins D2 and D3.

  13. Development and validation of the simultaneous measurement of four vitamin D metabolites in serum by LC-MS/MS for clinical laboratory applications.

    PubMed

    Satoh, Mamoru; Ishige, Takayuki; Ogawa, Shoujiro; Nishimura, Motoi; Matsushita, Kazuyuki; Higashi, Tatsuya; Nomura, Fumio

    2016-11-01

    The quantification of serum 25-hydroxyvitamin D [25(OH)D] as an indicator of vitamin D status is currently primarily conducted by immunoassays, yet LC-MS/MS would allow more accurate determination. Furthermore, LC-MS/MS would allow simultaneous measurement of multiple analytes. The aim of this study was to develop and validate an LC-MS/MS method to simultaneously measure four vitamin D metabolites (25(OH)D3, 3-epi-25(OH)D3, 25(OH)D2, and 24,25(OH)2D3) in serum for clinical laboratory applications. Serum samples were first prepared in a 96-well supported liquid extraction plate and the eluate was derivatized using the Cookson-type reagent 4-(4'-dimethylaminophenyl)-1,2,4-triazoline-3,5-dione (DAPTAD), which rapidly and quantitatively reacts with the s-cis-diene structure of vitamin D metabolites. The derivatized samples were subjected to LC-MS/MS, ionized by electrospray ionization (positive-ion mode), and detected by selected reaction monitoring. The lower limits of quantification for 25(OH)D3, 3-epi-25(OH)D3, 25(OH)D2, and 24,25(OH)2D3 were 0.091, 0.020, 0.013, and 0.024 ng/mL, respectively. The accuracy values and the extraction recoveries for these four metabolites were satisfactory. Serum 25(OH)D levels determined by our LC-MS/MS were compared with those obtained by conventional radioimmunoassay (RIA) that cannot distinguish 25(OH)D3 and 25(OH)D2. The values obtained by the RIA method exhibited a mean bias of about 8.35 ng/mL, most likely as a result of cross reaction of the antibody with low-abundance metabolites, including 24,25(OH)2D3. Various preanalytical factors, such as long sample sitting prior to serum separation, repeated freeze-thaw cycles, and the presence of anticoagulants, had no significant effects on these determinations. This high-throughput LC-MS/MS simultaneous assay of the four vitamin D metabolites 25(OH)D3, 3-epi-25(OH)D3, 25(OH)D2, and 24,25(OH)2D3 required as little as 20 μL serum. This method will aid further understanding of

  14. Simultaneous determination of cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) in foods by selected reaction monitoring.

    PubMed

    Dimartino, Gianluca

    2009-01-01

    Cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2) were determined simultaneously by selected reaction monitoring (SRM) mass spectrometry for different food matrixes. A small amount of starting sample was saponified and extracted before injection into a linear ion trap mass spectrometer equipped with an atmospheric pressure chemical ionization source. Dihydrotachysterol, which is absent from food and has a structure similar to that of vitamins D3 and D2, was used as an internal standard. Calibration curves for the 2 vitamins showed linearity with R2 values of 0.9999 and 0.9989 for vitamins D3 and D2, respectively. Limits of detection for vitamins D3 and D2 were 0.5 ng/g (1.3 pmol/g) and 1.75 ng/g (4.4 pmol/g) and limits of quantitation were 1.25 ng/g (3.24 pmol/g), and 3.75 ng/g (9.45 pmol/g), respectively. Accuracy and precision of the method were tested with the infant formula reference standard of the National Institute of Standards and Technology, which showed a relative standard deviation of 6%. Recoveries ranged from 95 to 105%. Several food products were tested with AOAC Method 982.29, which is currently in use for vitamins D3 and D2, and results were comparable within 6%.

  15. High pressure-assisted encapsulation of vitamin D2 in reassembled casein micelles

    NASA Astrophysics Data System (ADS)

    Menéndez-Aguirre, O.; Stuetz, W.; Grune, T.; Kessler, A.; Weiss, J.; Hinrichs, J.

    2011-03-01

    For the encapsulation of vitamin D2, native casein micelles and vitamin D2 with or without additional Ca2+-Pi were treated at 600 MPa and 37 °C for 60 min. The pressure release rate was set at 20 or 600 MPa/min. Vitamin D2 was quantified by reversed-phase high-performance liquid chromatography, and physical properties of the micelles were analysed by photon correlation spectroscopy. The results demonstrate that simultaneous application of Ca2+-Pi and high pressure treatment with a fast release rate significantly increased loading of vitamin D2 per casein by 6.9-fold. The addition of Ca2+-Pi enhanced micelle aggregation and the vitamin was entrapped within the formed aggregates. However, high pressure treatment without Ca2+-Pi with a slow pressure release rate revealed similar results, increasing vitamin D2 per casein by 6.7-fold. The vitamin D2 loading in reassembled casein micelles is supposed to be due to hydrophobic interactions between the hydrophobic domains of the micelles.

  16. Traditional foods and 25(OH)D concentrations in a subarctic First Nations community

    PubMed Central

    Mansuri, Sudaba; Badawi, Alaa; Kayaniyil, Sheena; Cole, David E.; Harris, Stewart B.; Mamakeesick, Mary; Wolever, Thomas; Gittelsohn, Joel; Maguire, Jonathon L.; Connelly, Philip W.; Zinman, Bernard; Hanley, Anthony J.

    2016-01-01

    Background Sub-optimal vitamin D status is common worldwide and the condition may be associated with increased risk for various chronic diseases. In particular, low vitamin D status is highly prevalent in indigenous communities in Canada, although limited data are available on the determinants of serum 25-hydroxyvitamin D (25(OH)D) concentrations in this population. The relationship between traditional food consumption and vitamin D status has not been well documented. Objective To investigate the determinants of serum 25(OH)D status in a First Nations community in Ontario, Canada, with a focus on the role of traditional food consumption and activities. Methods A cross-sectional analysis was conducted within the Sandy Lake Health and Diabetes Project (2003–2005). A total of 445 participants (>12 years of age) were assessed for serum 25(OH)D status, anthropometric and lifestyle variables, including traditional and non-traditional dietary practices and activities. Diet patterns were identified using factor analysis, and multivariate linear regression analysis was used to analyse the determinants of 25(OH)D concentrations. Results Mean serum 25(OH)D concentrations were 22.1 nmol/L (16.9, 29.9 nmol/L) in men and 20.5 nmol/L (16.0, 27.3 nmol/L) in women. Multivariate determinants of higher serum 25(OH)D included higher consumption of traditional and healthier market foods, higher wild fish consumption, male gender, spring/summer season of blood collection and more frequent physical activity. Significant negative determinants included hours of TV/day, higher BMI and higher consumption of unhealthy market foods. Conclusions Traditional food consumption contributed independently to higher 25(OH)D concentrations in a First Nations community with a high prevalence of sub-optimal vitamin D status. PMID:27664115

  17. Traditional foods and 25(OH)D concentrations in a subarctic First Nations community.

    PubMed

    Mansuri, Sudaba; Badawi, Alaa; Kayaniyil, Sheena; Cole, David E; Harris, Stewart B; Mamakeesick, Mary; Wolever, Thomas; Gittelsohn, Joel; Maguire, Jonathon L; Connelly, Philip W; Zinman, Bernard; Hanley, Anthony J

    2016-01-01

    Background Sub-optimal vitamin D status is common worldwide and the condition may be associated with increased risk for various chronic diseases. In particular, low vitamin D status is highly prevalent in indigenous communities in Canada, although limited data are available on the determinants of serum 25-hydroxyvitamin D (25(OH)D) concentrations in this population. The relationship between traditional food consumption and vitamin D status has not been well documented. Objective To investigate the determinants of serum 25(OH)D status in a First Nations community in Ontario, Canada, with a focus on the role of traditional food consumption and activities. Methods A cross-sectional analysis was conducted within the Sandy Lake Health and Diabetes Project (2003-2005). A total of 445 participants (>12 years of age) were assessed for serum 25(OH)D status, anthropometric and lifestyle variables, including traditional and non-traditional dietary practices and activities. Diet patterns were identified using factor analysis, and multivariate linear regression analysis was used to analyse the determinants of 25(OH)D concentrations. Results Mean serum 25(OH)D concentrations were 22.1 nmol/L (16.9, 29.9 nmol/L) in men and 20.5 nmol/L (16.0, 27.3 nmol/L) in women. Multivariate determinants of higher serum 25(OH)D included higher consumption of traditional and healthier market foods, higher wild fish consumption, male gender, spring/summer season of blood collection and more frequent physical activity. Significant negative determinants included hours of TV/day, higher BMI and higher consumption of unhealthy market foods. Conclusions Traditional food consumption contributed independently to higher 25(OH)D concentrations in a First Nations community with a high prevalence of sub-optimal vitamin D status.

  18. Dose-Response Effect of Sunlight on Vitamin D2 Production in Agaricus bisporus Mushrooms.

    PubMed

    Urbain, Paul; Jakobsen, Jette

    2015-09-23

    The dose response effect of UV-B irradiation from sunlight on vitamin D2 content of sliced Agaricus bisporus (white button mushroom) during the process of sun-drying was investigated.Real-time UV-B and UV-A data were obtained using a high-performance spectroradiometer. During the first hour of sunlight exposure, the vitamin D2 content of the mushrooms increased in a linear manner, with concentrations increasing from 0.1 μg/g up to 3.9 ± 0.8 μg/g dry weight (DW). At the subsequent two measurements one and 3 h later, respectively, a plateau was reached. Two hours of additional exposure triggered a significant decline in vitamin D2 content. After just 15 min of sun exposure and an UV-B dose of 0.13 J/cm(2), the vitamin D2 content increased significantly to 2.2 ± 0.5 μg/g DW (P < 0.0001), which is equivalent to 17.6 μg (704 IU) vitamin D2 per 100 g of fresh mushrooms and comparable to levels found in fatty fish like the Atlantic salmon.

  19. An alternative pathway of vitamin D2 metabolism Cytochrome P450scc (CYP11A1)-mediated conversion to 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2

    PubMed Central

    Slominski, Andrzej; Semak, Igor; Wortsman, Jacobo; Zjawiony, Jordan; Li, Wei; Zbytek, Blazej; Tuckey, Robert C.

    2007-01-01

    We report an alternative, hydroxylating pathway for the metabolism of vitamin D2 in a cytochrome P450 side chain cleavage (P450scc; CYP11A1) reconstituted system. NMR analyses identified solely 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2 derivatives. 20-Hydroxyvitamin D2 was produced at a rate of 0.34 mol·min−1·mol−1 P450scc, and 17,20-dihydroxyvitamin D2 was produced at a rate of 0.13 mol·min−1·mol−1. In adrenal mitochondria, vitamin D2 was metabolized to six monohydroxy products. Nevertheless, aminoglutethimide (a P450scc inhibitor) inhibited this adrenal metabolite formation. Initial testing of metabolites for biological activity showed that, similar to vitamin D2, 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2 inhibited DNA synthesis in human epidermal HaCaT keratinocytes, although to a greater degree. 17,20-Dihydroxyvitamin D2 stimulated transcriptional activity of the involucrin promoter, again to a significantly greater extent than vitamin D2, while the effect of 20-hydroxyvitamin D2 was statistically insignificant. Thus, P450scc can metabolize vitamin D2 to generate novel products, with intrinsic biological activity (at least in keratinocytes). PMID:16817851

  20. Effects of vitamin D2 or D3 supplementation on glycaemic control and cardiometabolic risk among people at risk of type 2 diabetes: results of a randomized double‐blind placebo‐controlled trial

    PubMed Central

    Menon, R. K.; Sharp, S. J.; Mannan, N.; Timms, P. M.; Martineau, A. R.; Rickard, A. P.; Boucher, B. J.; Chowdhury, T. A.; Griffiths, C. J.; Greenwald, S. E.; Griffin, S. J.; Hitman, G. A.

    2016-01-01

    Aims To investigate the effect of short‐term vitamin D supplementation on cardiometabolic outcomes among individuals with an elevated risk of diabetes. Methods In a double‐blind placebo‐controlled randomized trial, 340 adults who had an elevated risk of type 2 diabetes (non‐diabetic hyperglycaemia or positive diabetes risk score) were randomized to either placebo, 100 000 IU vitamin D2 (ergocalciferol) or 100 000 IU vitamin D3 (cholecalciferol), orally administered monthly for 4 months. The primary outcome was change in glycated haemoglobin (HbA1c) between baseline and 4 months, adjusted for baseline. Secondary outcomes included: blood pressure; lipid levels; apolipoprotein levels; C‐reactive protein levels; pulse wave velocity (PWV); anthropometric measures; and safety of the supplementation. Results The mean [standard deviation (s.d.)] 25‐hydroxyvitamin D [25(OH)D]2 concentration increased from 5.2 (4.1) to 53.9 (18.5) nmol/l in the D2 group, and the mean (s.d.) 25(OH)D3 concentration increased from 45.8 (22.6) to 83.8 (22.7) nmol/l in the D3 group. There was no effect of vitamin D supplementation on HbA1c: D2 versus placebo: −0.05% [95% confidence interval (CI) −0.11, 0.02] or −0.51 mmol/mol (95% CI −1.16, 0.14; p = 0.13); D3 versus placebo: 0.02% (95% CI −0.04, 0.08) or 0.19 mmol/mol (95% CI −0.46, 0.83; p = 0.57). There were no clinically meaningful effects on secondary outcomes, except PWV [D2 versus placebo: −0.68 m/s (95% CI −1.31, −0.05); D3 versus placebo −0.73 m/s (95% CI −1.42, −0.03)]. No important safety issues were identified. Conclusions Short‐term supplementation with vitamin D2 or D3 had no effect on HbA1c. The modest reduction in PWV with both D2 and D3 relative to placebo suggests that vitamin D supplementation has a beneficial effect on arterial stiffness. PMID:26700109

  1. Differential Responses to Vitamin D2 and Vitamin D3 Are Associated With Variations in Free 25-Hydroxyvitamin D.

    PubMed

    Chun, Rene F; Hernandez, Ivan; Pereira, Renata; Swinkles, Leon; Huijs, Tonnie; Zhou, Rui; Liu, Nancy Q; Shieh, Albert; Guemes, Miriam; Mallya, Sanjay M; Adams, John S; Hewison, Martin

    2016-09-01

    25-Hydroxyvitamin D (25D) circulates bound primarily to serum vitamin D binding protein (DBP), with DBP showing higher binding affinity for 25D3 than 25D2. We therefore hypothesized that vitamin D2 (D2) promotes higher serum levels of unbound 25D (free 25D), with different functional responses, relative to vitamin D3 (D3). Week 3 C56BL/6 mice were placed on diets containing either D2 or D3 alone (both 1000 IU/kg). At week 8 and week 16, D2 mice had only 25D2 in circulation (26.6 ± 1.9 and 33.3 ± 4.4 ng/mL), and D3 mice had only 25D3 (28.3 ± 2.0 and 31.7 ± 2.1 ng/mL). At week 8 (44.5 ± 6.4 vs 62.4 ± 11.6 pg/mL, P < .05) and week 16 (78.4 ± 12.6 vs 95.5 ± 11.6), D2 mice had lower serum 1,25-dihydroxyvitamin D relative to D3 mice. By contrast, measured free 25D was significantly higher in D2 mice at week 8 (16.8 ± 0.65 vs 8.4 ± 0.63 pg/mL, P < .001) and week 16 (17.4 ± 0.43 vs 8.4 ± 0.44, P < .001). A two-way ANOVA of bone histomorphometry showed that week 8 D2 mice had significantly higher osteoclast surface/bone surface, eroded surface/bone surface, and mineral apposition rate compared with D3 mice. Osteoblast surface/bone surface was higher in week 8 D2 females but not week 8 D2 males. At week 16, D2 mice had significantly higher bone volume/total volume and trabecular number compared with D3 mice. Differences in bone phenotype were observed despite D2 mice reaching similar serum 25D levels and lower 1,25D levels compared with D3 mice. These data indicate that 25D2 binds less well to DBP than 25D3, with resulting higher levels of free 25D promoting differential effects on bone in mice exposed to D2 alone.

  2. Interaction between vitamin D 2 and magnesium in liposomes: Differential scanning calorimetry and FTIR spectroscopy studies

    NASA Astrophysics Data System (ADS)

    Toyran, Neslihan; Severcan, Feride

    2007-08-01

    Magnesium (Mg 2+) ion is of great importance in physiology by its intervention in 300 enzymatic systems, its role in membrane structure, its function in neuromuscular excitability and vitamin D metabolism and/or action. In the present study, the interaction of Mg 2+, at low (1 mole %) and high (7 mole %) concentrations with dipalmitoyl phosphatidylcholine (DPPC) liposomes has been studied in the presence and absence of vitamin D 2 (1 mole %) by using two noninvasive techniques, namely differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy. DSC studies reveal that the presence of vitamin D 2 in the pure or Mg 2+ (at both low and high concentrations) containing liposomes diminishes the pretransition. The calorimetric results also reveal that, inclusion of Mg 2+ (more significantly at high concentration) into pure or vitamin D 2 containing DPPC liposomes increases the main phase transition temperature. The investigation of the CH 2 symmetric, the CH 3 asymmetric, the C dbnd O stretching, and the PO2- antisymmetric double bond stretching bands in FTIR spectra with respect to changes occurring in the wavenumber and/or the bandwidth values as a function of temperature reveal that, inclusion of vitamin D 2 or Mg 2+ into pure DPPC liposomes orders and decreases the dynamics of the acyl chains in both gel and liquid-crystalline phases and does not induce hydrogen bond formation in the interfacial region. Furthermore, the dynamics of the head groups of the liposomes decreases in both phases. Our findings reveal that, simultaneous presence of vitamin D 2 and Mg 2+ alters the effect of each other, which is reflected as a decrease in the interactions between these two additives within the model membrane.

  3. Potential determinants of vitamin D in Finnish adults: a cross-sectional study from the Northern Finland birth cohort 1966

    PubMed Central

    Palaniswamy, Saranya; Hyppönen, Elina; Williams, Dylan M; Jokelainen, Jari; Lowry, Estelle; Keinänen-Kiukaanniemi, Sirkka; Herzig, Karl-Heinz; Järvelin, Marjo-Riitta; Sebert, Sylvain

    2017-01-01

    Objective Evidence from randomised controlled trials suggests that vitamin D may reduce multimorbidity, but very few studies have investigated specific determinants of vitamin D2 and D3 (two isoforms of 25-hydroxyvitamin D). The aim of the study was to investigate the determinants of vitamin D2 and D3 and to identify the risk factors associated with hypovitaminosis D. Design Cross-sectional study. Setting Northern Finland Birth Cohort 1966. Participants 2374 male and 2384 female participants with data on serum 25(OH)D2 and 25(OH)D3 concentrations measured at 31 years of age (1997), together with comprehensive measures of daylight, anthropometric, social, lifestyle and contraceptive cofactors. Methods We assessed a wide range of potential determinants prior to a nationwide fortification programme introduced in Finland. The determinants of 25(OH)D2, 25(OH)D3 and 25(OH)D concentrations were analysed by linear regression and risk factors for being in lower tertile of 25(OH)D concentration by ordinal logistic regression. Results At the time of sampling, 72% of the participants were vitamin D sufficient (≥50 nmol/L). Low sunlight exposure period (vs high) was associated positively with 25(OH)D2 and negatively with 25(OH)D3 concentrations. Use of oral contraceptives (vs non-users) was associated with an increase of 0.17 nmol/L (95% CI 0.08 to 0.27) and 0.48 nmol/L (95% CI 0.41 to 0.56) in 25(OH)D2 and 25(OH)D3 concentrations. Sex, season, latitude, alcohol consumption and physical activity were the factors most strongly associated with 25(OH)D concentration. Risk factors for low vitamin D status were low sunlight exposure defined by time of sampling, residing in northern latitudes, obesity, higher waist circumference, low physical activity and unhealthy diet. Conclusions We demonstrate some differential associations of environmental and lifestyle factors with 25(OH)D2 and 25(OH)D3 raising important questions related to personalised healthcare. Future strategies

  4. Relationship of calcium absorption with 25(OH)D and calcium intake in children with rickets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Nutritional rickets has long been considered a disease caused by vitamin D deficiency, but recent data indicate that inadequate dietary calcium intake is an important cause of rickets, particularly in tropical countries. Children with rickets due to calcium deficiency do not have very low 25(OH) D c...

  5. Enhancement of Vitamin D Metabolites in the Eye following Vitamin D3 Supplementation and UV-B Irradiation

    PubMed Central

    Lin, Yanping; Ubels, John L.; Schotanus, Mark P.; Yin, Zhaohong; Pintea, Victorina; Hammock, Bruce D.; Watsky, Mitchell A.

    2013-01-01

    Purpose This study was designed to measure vitamin D metabolites in the aqueous and vitreous humor and in tear fluid, and to determine if dietary vitamin D3 supplementation affects these levels. We also determined if the corneal epithelium can synthesize vitamin D following UV-B exposure. Methods Rabbits were fed a control or vitamin D3 supplemented diet. Pilocarpine-stimulated tear fluid was collected and aqueous and vitreous humor were drawn from enucleated eyes. Plasma vitamin D was also measured. To test for epithelial vitamin D synthesis, a human corneal limbal epithelial cell line was irradiated with two doses of UV-B (10 and 20 mJ/cm2/day for three days) and vitamin D was measured in control or 7-dehydrocholesterol treated culture medium. Measurements were made using mass spectroscopy. Results 25(OH)-vitamin D3 and 24,25(OH)2-vitamin D3 increased significantly following D3 supplementation in all samples except vitreous humor. Tear fluid and aqueous humor had small but detectable 1,25(OH)2-vitamin D3 levels. Vitamin D2 metabolites were observed in all samples. Vitamin D3 levels were below the detection limit for all samples. Minimal vitamin D3 metabolites were observed in control and UV-B-irradiated epithelial culture medium except following 7-dehydrocholesterol treatment, which resulted in a UV-B-dose dependent increase in vitamin D3, 25(OH)-vitamin D3 and 24,25(OH)2-vitamin D3. Conclusions There are measurable concentrations of vitamin D metabolites in tear fluid and aqueous and vitreous humor, and oral vitamin D supplementation affects vitamin D metabolite concentrations in the anterior segment of the eye. In addition, the UV exposure results lead us to conclude that corneal epithelial cells are likely capable of synthesizing vitamin D3 metabolites in the presence of 7-dehydrocholesterol following UV-B exposure. PMID:22632164

  6. 25(OH)D Status of Elite Athletes with Spinal Cord Injury Relative to Lifestyle Factors

    PubMed Central

    Pritchett, Kelly; Pritchett, Robert; Ogan, Dana; Bishop, Phil; Broad, Elizabeth; LaCroix, Melissa

    2016-01-01

    Background: Due to the potential negative impact of low Vitamin D status on performance-related factors and the higher risk of low Vitamin D status in Spinal Cord Injury (SCI) population, research is warranted to determine whether elite athletes with SCI have sufficient 25(OH)D levels. The purposes of this study were to examine: (1) the seasonal proportion of vitamin D insufficiency among elite athletes with SCI; and (2) to determine whether lifestyle factors, SCI lesion level, and muscle performance/function are related to vitamin D status in athletes with SCI. Methods: Thirty-nine members of the Canadian Wheelchair Sports Association, and the US Olympic Committee Paralympic program from outdoor and indoor sports were recruited for this study. Dietary and lifestyle factors, and serum 25(OH)D concentrations were assessed during the autumn (October) and winter (February/March). An independent t-test was used to assess differences in 25(OH)D status among seasons, and indoor and outdoor sports in the autumn and winter, respectively. Results: Mean ± SD serum 25(OH)D concentration was 69.6 ± 19.7 nmol/L (range from 30 to 107.3 nmol/L) and 67.4 ± 25.5 nmol/L (range from 20 to 117.3 nmol/L)in the autumn and winter, respectively. In the autumn, 15.4% of participants were considered vitamin D deficient (25(OH)D < 50 nmol/L) whereas 51.3% had 25(OH)D concentrations that would be considered insufficient (<80 nmol/L). In the winter, 15.4% were deficient while 41% of all participants were considered vitamin D insufficient. Conclusion: A substantial proportion of elite athletes with SCI have insufficient (41%–51%) and deficient (15.4%) 25(OH)D status in the autumn and winter. Furthermore, a seasonal decline in vitamin D status was not observed in the current study. PMID:27322316

  7. Determination of 1,25-dihydroxyvitamin D2 and 1,25-dihydroxyvitamin D3 in human serum using liquid chromatography with tandem mass spectrometry.

    PubMed

    Fang, Huiling; Yu, Songlin; Cheng, Qian; Cheng, Xinqi; Han, Jianhua; Qin, Xuzhen; Xia, Liangyu; Jiang, Xiaomei; Qiu, Ling

    2016-08-01

    Vitamin D plays important roles in skeletal metabolism and many other diseases, including chronic renal failure, hypoparathyroidism, sarcoidosis and rickets. 1α,25-dihydroxy vitamin D (1α,25(OH)2D), the active form of vitamin D, exhibits an extremely low serum concentration, which makes its quantification very challenging. High performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) is considered to be the "gold standard" for the determination of these chemicals, which are found in low concentrations in the serum, but conventionally, it needs tedious sample pretreatment procedures, such as solid phase extraction and derivatization. Herein, we describe a simple and rapid HPLC-MS/MS method for the simultaneous quantification of 1α,25-dihydroxy vitamin D3 (1α,25(OH)2D3) and 1α,25-dihydroxy vitamin D2 (1α,25(OH)2D2). The analytes were extracted from the matrix by liquid-liquid extraction, centrifuged to dryness and reconstituted with 75% methanol. Lithium acetate was employed to improve the ionization efficiency of 1α,25(OH)2D. The assay was sensitive with a low limit of quantitation of 10.0pg/mL for both 1α,25(OH)2D3 and 1α,25(OH)2D2 using a 0.5mL sample aliquot. Linearity was obtained over the range of 10.0pg/mL to 500pg/mL. Both the inter-assay and intra-assay precisions were <15%, and the analytical recoveries were within 100±5%. The performance evaluation of this assay demonstrated that it was a practical, sensitive and specific method for measuring the serum 1α,25(OH)2D3 and 1α,25(OH)2D2 concentrations.

  8. 1,25(OH)2vitamin D3 Enhances Myogenic Differentiation by Modulating the Expression of Key Angiogenic Growth factors and Angiogenic Inhibitors in C2C12 Skeletal Muscle Cells

    PubMed Central

    Garcia, Leah A.; Ferrini, Monica G.; Norris, Keith C.; Artaza, Jorge N.

    2012-01-01

    Vitamin D is mostly recognized for its regulation of calcium homeostasis in relation to the intestine, kidney, and bone. Although clinical studies have linked vitamin D with increased muscle function and strength, little is known of its underlying molecular mechanism. We recently demonstrated that 1,25-D3 exerts a direct pro-myogenic effect on skeletal muscle cells; this has provoked our investigation of 1,25-D’s effect on angiogenesis, a vital process for new capillary development and tissue repair. In this study, we examined the mechanism by which 1,25-D3 modulates key angiogenic growth factors and angiogenic inhibitors. C2C12 myoblasts were incubated with 100 nM 1,25-D3 or placebo for 1, 4 and 10 days. At the end of the respective incubation time, total RNA was isolated for PCR arrays and for qRT-PCR. Total proteins were isolated for western blots and proteome profiler arrays. The addition of 1,25-D3 to C2C12 myoblasts increased VEGFa and FGF-1: two pro-angiogenic growth factors that promote neo-vascularization and tissue regeneration, and decreased FGF-2 and TIMP-3: two myogenic and/or angiogenic inhibitors. Our previous study demonstrated that 1,25-D3 altered IGF-I/II expression, consistent with the observed changes in VEGFa and FGF-2 expression. These results extend our previous findings and demonstrate the modulation of angiogenesis which may be an additional mechanism by which 1,25-D3 promotes myogenesis. This study supports the mechanistic rationale for assessing the administration of vitamin D and/or vitamin D analogues to treat select muscle disorders and may also provide an alternative solution for therapies that directly manipulate VEGF and FGF’s to promote angiogenesis. PMID:22982629

  9. Plasma appearance and disappearance of an oral dose of 25-hydroxyvitamin D2 in healthy adults

    PubMed Central

    Jones, Kerry S.; Schoenmakers, Inez; Bluck, Les J. C.; Ding, Shujing; Prentice, Ann

    2012-01-01

    25-Hydroxyvitamin D (25(OH)D) half-life is a potential biomarker for investigating vitamin D metabolism and requirements. We performed a pilot study to assess the approach and practical feasibility of measuring 25(OH)D half-life after an oral dose. A total of twelve healthy Gambian men aged 18–23 years were divided into two groups to investigate the rate and timing of (1) absorption and (2) plasma disappearance after an 80 nmol oral dose of 25(OH)D2. Fasting blood samples were collected at baseline and, in the first group, every 2 h post-dose for 12 h, at 24 h, 48 h and on day 15. In the second group, fasting blood samples were collected on days 3, 4, 5, 6, 9, 12, 15, 18 and 21. Urine was collected for 2 h after the first morning void at baseline and on day 15. 25(OH)D2 plasma concentration was measured by ultra-performance liquid chromatography-tandem MS/MS and corrected for baseline. Biomarkers of vitamin D, Ca and P metabolism were measured at baseline and on day 15. The peak plasma concentration of 25(OH)D2 was 9·6 (sd 0·9) nmol/l at 4·4 (sd 1·8) h. The terminal slope of 25(OH)D2 disappearance was identified to commence from day 6. The terminal half-life of plasma 25(OH)D2 was 13·4 (sd 2·7) d. There were no significant differences in plasma 25(OH)D3, total 1,25(OH)2D, parathyroid hormone, P, Ca and ionised Ca and urinary Ca and P between baseline and day 15 and between the two groups. The present study provides data on the plasma response to oral 25(OH)D2 that will underpin and contribute to the further development of studies to investigate 25(OH)D half-life. PMID:21896243

  10. Plasma appearance and disappearance of an oral dose of 25-hydroxyvitamin D2 in healthy adults.

    PubMed

    Jones, Kerry S; Schoenmakers, Inez; Bluck, Les J C; Ding, Shujing; Prentice, Ann

    2012-04-01

    25-Hydroxyvitamin D (25(OH)D) half-life is a potential biomarker for investigating vitamin D metabolism and requirements. We performed a pilot study to assess the approach and practical feasibility of measuring 25(OH)D half-life after an oral dose. A total of twelve healthy Gambian men aged 18-23 years were divided into two groups to investigate the rate and timing of (1) absorption and (2) plasma disappearance after an 80 nmol oral dose of 25(OH)D2. Fasting blood samples were collected at baseline and, in the first group, every 2 h post-dose for 12 h, at 24 h, 48 h and on day 15. In the second group, fasting blood samples were collected on days 3, 4, 5, 6, 9, 12, 15, 18 and 21. Urine was collected for 2 h after the first morning void at baseline and on day 15. 25(OH)D2 plasma concentration was measured by ultra-performance liquid chromatography-tandem MS/MS and corrected for baseline. Biomarkers of vitamin D, Ca and P metabolism were measured at baseline and on day 15. The peak plasma concentration of 25(OH)D2 was 9·6 (sd 0·9) nmol/l at 4·4 (sd 1·8) h. The terminal slope of 25(OH)D2 disappearance was identified to commence from day 6. The terminal half-life of plasma 25(OH)D2 was 13·4 (sd 2·7) d. There were no significant differences in plasma 25(OH)D3, total 1,25(OH)2D, parathyroid hormone, P, Ca and ionised Ca and urinary Ca and P between baseline and day 15 and between the two groups. The present study provides data on the plasma response to oral 25(OH)D2 that will underpin and contribute to the further development of studies to investigate 25(OH)D half-life.

  11. Iatrogenic vitamin D toxicity in an infant--a case report and review of literature.

    PubMed

    Ketha, Hemamalini; Wadams, Heather; Lteif, Aida; Singh, Ravinder J

    2015-04-01

    Public concern over vitamin D deficiency has led to widespread use of over the counter (OTC) vitamin D (-D3 or -D2) supplements, containing up to 10,000 IU/unit dose (400 IU=10μg). Overzealous use of such supplements can cause hypercalcemia due to vitamin D toxicity. Infants are particularly vulnerable to toxicity associated with vitamin D overdose. OTC supplements are not subject to stringent quality control regulations from FDA and high degree of variability in vitamin D content in OTC pills has been demonstrated. Other etiologies of vitamin D induced hypercalcemia include hyperparathyroidism, granulomatous malignancies like sarcoidosis and mutations in the CYP24A1 gene. The differential diagnosis of hypercalcemia should include iatrogenic and genetic etiologies. C24-hydroxylation and C3-epimerization are two important biochemical pathways via which 25-hydroxyvitamin D3 (25(OH)D3) is converted to its metabolites, 24,25-dihydroxyvitamin D3 (24,25(OH)2D3) or its C3 epimer, 3-epi-25-OH-D3 respectively. Mutations in the CYP24A1 gene cause reduced serum 24,25(OH)2D3 to 25(OH)D3 ratio (<0.02), elevated serum 1,25-dihydroxyvitamin D (1,25(OH)2D3), hypercalcemia, hypercalciuria and nephrolithiasis. Studies in infants have shown that 3-epi-25(OH)D3 can contribute 9-61.1% of the total 25(OH)D3. Therefore, measurements of parathyroid hormone (PTH) and vitamin D metabolites 25(OH)D3, 1,25(OH)2D3, 3-epi-25(OH)D3 and 24,25(OH)2D3 are useful to investigate whether the underlying cause of vitamin D toxicity is iatrogenic versus genetic. Here we report a case of vitamin D3 associated toxicity in a 4-month-old female who was exclusively breast-fed and received an oral liquid vitamin D3 supplement at a dose significantly higher than recommended on the label. The vitamin D3 content of the supplement was threefold higher (6000 IU of D/drop) than listed on the label (2000 IU). Due to overdosing and higher vitamin D3 content, the infant received ∼50,000 IU/day for two months

  12. 1,25(OH)2D3 dependent overt hyperactivity phenotype in klotho-hypomorphic mice

    PubMed Central

    Leibrock, Christina B.; Voelkl, Jakob; Kuro-o, Makoto; Lang, Florian; Lang, Undine E

    2016-01-01

    Klotho, a protein mainly expressed in kidney and cerebral choroid plexus, is a powerful regulator of 1,25(OH)2D3 formation. Klotho-deficient mice (kl/kl) suffer from excessive plasma 1,25(OH)2D3-, Ca2+- and phosphate-concentrations, leading to severe soft tissue calcification and accelerated aging. NH4Cl treatment prevents tissue calcification and premature ageing without affecting 1,25(OH)2D3-formation. The present study explored the impact of excessive 1,25(OH)2D3 formation in NH4Cl-treated kl/kl-mice on behavior. To this end kl/kl-mice and wild-type mice were treated with NH4Cl and either control diet or vitamin D deficient diet (LVD). As a result, plasma 1,25(OH)2D3-, Ca2+- and phosphate-concentrations were significantly higher in untreated and in NH4Cl-treated kl/kl-mice than in wild-type mice, a difference abrogated by LVD. In each, open field, dark-light box, and O-maze NH4Cl-treated kl/kl-mice showed significantly higher exploratory behavior than untreated wild-type mice, a difference abrogated by LVD. The time of floating in the forced swimming test was significantly shorter in NH4Cl treated kl/kl-mice compared to untreated wild-type mice and to kl/kl-mice on LVD. In wild-type animals, NH4Cl treatment did not significantly alter 1,25(OH)2D3, calcium and phosphate concentrations or exploratory behavior. In conclusion, the excessive 1,25(OH)2D3 formation in klotho-hypomorphic mice has a profound effect on murine behavior. PMID:27109615

  13. Development and certification of a standard reference material for vitamin D metabolites in human serum.

    PubMed

    Phinney, Karen W; Bedner, Mary; Tai, Susan S-C; Vamathevan, Veronica V; Sander, Lane C; Sharpless, Katherine E; Wise, Stephen A; Yen, James H; Schleicher, Rosemary L; Chaudhary-Webb, Madhulika; Pfeiffer, Christine M; Betz, Joseph M; Coates, Paul M; Picciano, Mary Frances

    2012-01-17

    The National Institute of Standards and Technology (NIST), in collaboration with the National Institutes of Health's Office of Dietary Supplements (NIH-ODS), has developed a Standard Reference Material (SRM) for the determination of 25-hydroxyvitamin D [25(OH)D] in serum. SRM 972 Vitamin D in Human Serum consists of four serum pools with different levels of vitamin D metabolites and has certified and reference values for 25(OH)D(2), 25(OH)D(3), and 3-epi-25(OH)D(3). Value assignment of this SRM was accomplished using a combination of three isotope-dilution mass spectrometry approaches, with measurements performed at NIST and at the Centers for Disease Control and Prevention (CDC). Chromatographic resolution of the 3-epimer of 25(OH)D(3) proved to be essential for accurate determination of the metabolites.

  14. Serum 25(OH)D and adipokines levels in people with abdominal obesity.

    PubMed

    Karonova, T; Belyaeva, O; Jude, E B; Tsiberkin, A; Andreeva, A; Grineva, E; Pludowski, P

    2016-09-11

    Abdominal obesity is a risk factor for cardiovascular disease and diabetes mellitus and has been associated with vitamin D deficiency. Some studies have suggested an association between obesity and adipokine levels as well as low serum 25-hydroxyvitamin D (25(OH)D) level but the underlying mechanisms of the interlink between vitamin D status and serum leptin and adiponectin concentrations are still disputed. We included 435 residents (132 males) from St. Petersburg, Russia into this study. All subjects had physical examination and demographics noted. Blood was collected after an overnight fast and plasma glucose, insulin, serum lipids, 25(OH)D and adipokines (adiponectin and leptin) concentrations were determined at baseline in all participants. Abdominal obesity was diagnosed in 310 (71.3%) subjects (251 females and 59 males). Vitamin D insufficiency and deficiency were found in 314 (72.2%) subjects. Mean (95% CI) age, body mass index (BMI) and serum 25(OH)D for the cohort were 47.6±11.3years; 28.7±0.2kg/m(2) and 62.5±24.3nmol/l respectively. Serum 25(OH)D level inversely correlated with body weight, waist circumference (WC) and BMI in females but not in males, was lower in diabetic than non-diabetic subjects, and was not significantly different in subjects with and without MetS. WC was positively correlated with leptin and negatively correlated with adiponectin. We found correlation between leptin and serum 25(OH)D level (r=-0.15, p=0.01) but this finding was a characteristic seen only in women. Our study showed a high prevalence of abdominal obesity, vitamin D deficiency and insufficiency in residents from North-West region of Russia, close association between adipokine (leptin, adiponectin) concentrations as well as vitamin D status and body composition (WC, BMI). However in our study the interlink between leptin level and 25(OH)D was found only in females. Further investigations are required to study the relationship between serum 25(OH)D level, obesity and

  15. Serum Vitamin D Levels and Vitamin D Supplement in Adult Patients with Asthma Exacerbation

    PubMed Central

    Chantveerawong, Teerapol; Pradubpongsa, Panitan; Sangasapaviliya, Atik

    2016-01-01

    Introduction. Vitamin D deficiency has been linked to an increased risk of asthma exacerbations. Objective. This study aimed to compare vitamin D status during the period of severe asthma exacerbations and investigate if vitamin D supplementation improves asthma control. Methods. A total of 47 asthmatic patients and 40 healthy subjects participated in this study. Serum 25-hydroxyvitamin D (25(OH)D), asthma control test (ACT) score, and % predicted peak expiratory flow rate were evaluated in the period with and without severe asthma exacerbations. After that, we provided vitamin D2 supplements to the patients with low vitamin D levels for 3 months. Results. At the period of asthma exacerbation, the prevalence of vitamin D deficiency and insufficiency was 38.29% and 34.04%. There was no significant difference in the levels of serum 25(OH)D with and without asthma exacerbations but the levels were significantly higher in the healthy group. Serum 25(OH)D levels significantly correlated with ACT score. Moreover, vitamin D2 supplementation improved asthma control in uncontrolled asthma group. Conclusions. Hypovitaminosis D was common in asthmatic patients but was not the leading cause of asthma exacerbations. Serum 25(OH)D levels correlated with the ability to control asthma. Improving vitamin D status might be a benefit in uncontrolled asthmatic patients. PMID:27974898

  16. 25(OH)D3 and Cardiovascular Risk Factors in Female Nonhuman Primates

    PubMed Central

    Jorgensen, Matthew J.; Rudel, Lawrence L.; Nudy, Matthew; Kaplan, Jay R.; Clarkson, Thomas B.; Pajewski, Nicholas M.

    2012-01-01

    Abstract Objective To determine if interindividual differences in plasma concentrations of 25-hydroxyvitamin D3 (25(OH)D3) have pathophysiologic significance, we evaluated a cohort of female monkeys, seeking to identify associations with clinically relevant cardiovascular risk factors, including age, abdominal obesity (waist circumference), and high-density lipoprotein cholesterol (HDL-C). Methods One hundred fifty-five female vervet monkeys (Chlorocebus aethiops sabaeus) aged 3–25 years consumed a typical western diet for 7–8 weeks that provided a woman's equivalent of approximately 1000 IU/day of vitamin D3. Measurements of vitamin D3 and HDL-C concentrations, as well as waist circumference, were obtained. Results Among young monkeys (aged 3–5 years), compared to older monkeys (aged 16–25 years), the mean plasma 25(OH)D3 concentrations were 82.3±3.2 ng/mL and 58.6±2.9 ng/mL (p<0.0001), respectively. Plasma 25(OH)D3 concentrations had a range of 19.6–142.0 ng/mL (mean±standard error [SE] 66.4±1.7 ng/mL). 25(OH)D3 concentrations were inversely associated with age (p<0.0001) and waist circumference (p=0.016) and were positively correlated with HDL-C (p=0.01). However, when statistically controlling for age, none of these relationships remained significant. Conclusions Higher plasma concentrations of 25(OH)D3 were associated with more favorable cardiovascular risk factors, with inverse associations observed between 25(OH)D3 and abdominal obesity, HDL-C, and age. These associations were no longer significant when controlling for age. PMID:22876774

  17. Low Vitamin D Status: Definition, Prevalence, Consequences and Correction

    PubMed Central

    Binkley, Neil; Ramamurthy, Rekha; Krueger, Diane

    2014-01-01

    Vitamin D is obtained from cutaneous production when 7-dehydrocholesterol is converted to vitamin D3 (cholecalciferol) by ultraviolet B radiation or by oral intake of vitamin D2 (ergocalciferol) and D3. An individual's vitamin D status is best evaluated by measuring the circulating 25-hydroxyvitamin D [25(OH)D] concentration. Though controversy surrounds the definition of low vitamin D status, there is increasing agreement that the optimal circulating 25(OH)D level should be ~30-32 ng/ml or above. Using this definition, it has been is estimated that approximately three quarters of all adults in the United States are low. Classically, low vitamin D status has skeletal consequences such as osteomalacia/rickets. More recently, associations between low vitamin D status and increased risk for various non-skeletal morbidities have been recognized; whether all of these associations are causally related to low vitamin D status remains to be determined. To achieve optimal vitamin D status, daily intakes of at least 1000 IU or more of vitamin D are required. The risk of toxicity with “high” amounts of vitamin D intake is low. Substantial between-individual variability exists in response to the same administered vitamin D dose. When to monitor 25(OH)D levels has received little attention. Supplementation with vitamin D3 may be preferable to vitamin D2. PMID:20511052

  18. Lower Vitamin D Metabolites Levels Were Associated With Increased Coronary Artery Diseases in Type 2 Diabetes Patients in India

    PubMed Central

    Adela, Ramu; Borkar, Roshan M; Bhandi, Murali Mohan; Vishwakarma, Gayatri; Reddy, P. Naveen Chander; Srinivas, R.; Banerjee, Sanjay K

    2016-01-01

    The purpose of the present study was to measure six vitamin D metabolites and to find the association between vitamin D deficiency and coronary artery diseases in diabetes (T2DM_CAD). Four groups [control (n = 50), type 2 diabetes (T2DM, n = 71), coronary artery diseases (CAD, n = 28), T2DM_CAD (n = 38)] of total 187 subjects were included in the study. Six vitamin D metabolites (D2, D3, 25(OH)D2, 25(OH)D3, 1,25(OH)2D2, 1,25(OH)2D3), total 25(OH)D and total 1,25(OH)2D were measured by UPLC/APCI/HRMS method in these subjects. Although all the vitamin D metabolites were significantly decreased in T2DM_CAD as compared to both control and T2DM subjects (p < 0.05), only two metabolites i.e., 25(OH)D3 and total 25(OH)D were significantly (p < 0.05) decreased in the T2DM subjects as compared with the control subjects (p < 0.05). Vitamin D3, 1,25(OH)2D2, 25(OH)D, and 1,25(OH)2D levels were significantly decreased in T2DM_CAD subjects as compared with CAD subjects (p < 0.05). Further, multiple logistic regression analysis revealed that total 25(OH)D and total 1,25(OH)2D can be used to predict T2DM (OR 0.82.95% CI 0.68–0.99; p = 0.0208) and T2DM with CAD (OR 0.460, 95% CI 0.242–0.874; p = 0.0177), respectively. Our data concludes that lower concentration of 1,25(OH)2D is associated with type 2 diabetes coexisting with coronary artery diseases in South Indian subjects. PMID:27883024

  19. 25(OH)D3 Levels Relative to Muscle Strength and Maximum Oxygen Uptake in Athletes

    PubMed Central

    Zagrodna, Aleksandra; Dziubek, Wioletta; Pietraszewski, Bogdan; Ochmann, Bartosz; Słowińska – Lisowska, Małgorzata

    2016-01-01

    Abstract Vitamin D is mainly known for its effects on the bone and calcium metabolism. The discovery of Vitamin D receptors in many extraskeletal cells suggests that it may also play a significant role in other organs and systems. The aim of our study was to assess the relationship between 25(OH)D3 levels, lower limb isokinetic strength and maximum oxygen uptake in well-trained professional football players. We enrolled 43 Polish premier league soccer players. The mean age was 22.7±5.3 years. Our study showed decreased serum 25(OH)D3 levels in 74.4% of the professional players. The results also demonstrated a lack of statistically significant correlation between 25(OH)D3 levels and lower limb muscle strength with the exception of peak torque of the left knee extensors at an angular velocity of 150°/s (r=0.41). No significant correlations were found between hand grip strength and maximum oxygen uptake. Based on our study we concluded that in well-trained professional soccer players, there was no correlation between serum levels of 25(OH)D3 and muscle strength or maximum oxygen uptake. PMID:28149343

  20. Development and validation of an LC-MS/MS based method for quantification of 25 hydroxyvitamin D2 and 25 hydroxyvitamin D3 in human serum and plasma.

    PubMed

    Zhang, Stanley Weihua; Jian, Wenying; Sullivan, Sheryl; Sankaran, Banu; Edom, Richard W; Weng, Naidong; Sharkey, David

    2014-06-15

    Vitamin D deficiency is increasing in the general population and has become a serious public health risk globally. As a reliable clinical indicator of vitamin status, 25 hydroxyvitamin D (25(OH)D) has been measured by various methods. However, the accuracy of these measurements has been the subject of considerable debate. Here, we report the development and validation of a liquid chromatography-triple quadrupole mass spectrometry based method for the quantification of 25(OH)D2 and 25(OH)D3 in human serum and plasma samples. Samples were first processed by protein precipitation to release the analytes from the vitamin D binding protein (DBP), followed by a liquid-liquid extraction procedure. Analysis was performed on an LC-MS/MS system which utilized an AB Sciex API 3000 mass spectrometer. A six point calibration curve ranging from 2.5 to 100ng/mL was established for both 25(OH)D2 and 25(OH)D3. A complete method validation was conducted, including intra- and inter-assay accuracy and precision, LLOQ, dilution QC, specificity, recovery, matrix effect, and a thorough stability profile of stock solutions and QC samples. Matching samples of serum and plasma (containing either heparin or EDTA anticoagulant) generated from the same blood samples were tested, and no significant differences in 25(OH)D2 and 25(OH)D3 concentrations were found in these sample matrices. In method comparison, we analyzed 10 serum samples obtained from the Vitamin D External Quality Assessment Scheme (DEQAS), and the total 25(OH)D concentrations measured by our method were very close to the LC-MS/MS Method Mean values provided by DEQAS (average 0.17% bias, R(2)=0.99). However, comparison with the DiaSorin Liaison 25(OH)D TOTAL Assay demonstrated limited correlation between these two methods (R(2)=0.54). In general, concentrations measured by our LC-MS/MS method were roughly 9% higher than those measured by the DiaSorin Liaison assay. The correlation with DiaSorin Liaison measurement was better for

  1. Effect of vitamin D2- and D3-enriched diets on egg vitamin D content, production, and bird condition during an entire production period.

    PubMed

    Mattila, P; Valaja, J; Rossow, L; Venäläinen, E; Tupasela, T

    2004-03-01

    Vitamin D insufficiency during winter is a common problem for humans in Europe. One way to ease this problem is through the production of vitamin D-fortified eggs. To evaluate such a production process, the effects of vitamin D supplementation during an entire production period were assessed. Transfer of vitamin D3 (cholecalciferol) and vitamin D2 (ergocalciferol) from the diet to egg yolks was measured using 2 different levels of both vitamins (6,000 and 15,000 IU/kg feed) relative to a control treatment (2,500 IU vitamin D3/kg feed). During the experiment, production parameters, egg quality (egg weight, Haugh unit, specific gravity, eggshell fracture force, and Ca content of eggshell), and the condition of hens were monitored. At the end of the experiment histopathological tests were performed. Supplementing diets with vitamin D3 increased egg yolk vitamin D content more effectively than did supplementation with vitamin D2. For groups of hens receiving 6,000 or 15,000 IU of vitamin D3/kg feed, egg yolk vitamin D3 content ranged from 9.1 to 13.6 and from 25.3 to 33.7 microg/100 g, respectively. Corresponding values for birds fed vitamin D2 were 4.7 to 7.0 and 13.3 to 21.0 microg/100 g. Both supplements enhanced vitamin D3 content of egg yolks relative to the control diet (2.5 to 5.0 microg/100 g of egg yolk). Vitamin D supplements had no effects on production parameters compared with the control diet. However, especially vitamin D3 improved bone strength (P < 0.05). Autopsy at the end of the experiment indicated no detrimental accumulation of calcium in the kidneys, liver, heart, muscles, or lungs.

  2. Development and optimization of an LC-MS/MS-based method for simultaneous quantification of vitamin D2 , vitamin D3 , 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3.

    PubMed

    Adamec, Jiri; Jannasch, Amber; Huang, Jianjie; Hohman, Emily; Fleet, James C; Peacock, Munro; Ferruzzi, Mario G; Martin, Berdine; Weaver, Connie M

    2011-01-01

    Simultaneous and accurate measurement of vitamin D and 25-hydroxyvitamin D in biological samples is a barrier limiting our ability to define "optimal" vitamin D status. Thus, our goal was to optimize conditions and evaluate an LC-MS method for simultaneous detection and quantification of vitamin D(2) , vitamin D(3) , 25-hydroxyvitamin D(2) and 25-hydroxyvitamin D(3) in serum. Extraction and separation of vitamin D forms were achieved using acetone liquid-liquid extraction and by a reversed phase C8 column, respectively. Detection was performed on a triple quadrupole tandem mass spectrometer (QQQ-MS/MS) equipped with atmospheric pressure photo ionization source. The LOQs for all analytes tested were 1 ng/mL for hydroxylated molecules and 2 ng/mL for the parent vitamin Ds. RSD at lower LOQ (2 ng/mL) and in medium (80 ng/mL) and high (200 ng/mL) quality control samples did not exceed 20 and 15% CV, respectively. Accuracy of the method for determination of hydroxylated molecules was also validated using National Institutes of Standards and Technology standard samples and found to be in the range of 90.9-111.2%. In summary, a sensitive and reproducible method is reported for simultaneous quantification of vitamin D(2) , vitamin D(3) , 25-hydroxyvitamin D(2) and 25-hydroxyvitamin D(3) molecules in biological samples.

  3. Genetic and environmental predictors of serum 25(OH)D concentrations among middle-aged and elderly Chinese in Singapore

    PubMed Central

    Robien, Kim; Butler, Lesley M.; Wang, Renwei; Beckman, Kenneth B.; Walek, Dinesha; Koh, Woon-Puay; Yuan, Jian-Min

    2012-01-01

    Vitamin D is known for maintaining calcium homeostasis and bone structure, and may also decrease susceptibility to chronic and infectious diseases. However, data on vitamin D status and its predictors among Southeast Asian populations is limited. We evaluated the distribution and determinants (genetic and environmental) of serum 25-hydroxyvitamin D (25(OH)D) concentrations among 504 middle-aged and elderly participants (aged 45–74 years) in the Singapore Chinese Health Study. Data on dietary and other lifestyle factors were collected by trained interviewers. Serum 25(OH)D concentrations and genetic polymorphisms in vitamin D metabolism pathway enzymes [cytochrome P450 (CYP) 2R1, 3A4, 27B1, 24A1; vitamin D binding protein (GC); and vitamin D receptor (VDR)] were measured using stored biospecimens. Mean 25(OH)D concentration was 68.8 nmol/L. Serum 25(OH)D concentrations were positively associated with dietary vitamin D intake, and inversely associated with hours sitting at work. BMI was not associated with 25(OH)D concentrations. CYP2R1 rs10741657, rs12794714, rs1993116; CYP3A4 rs2242480; and GC rs4588, rs7041, rs16847015, rs2298849 were statistically significantly associated with 25(OH)D concentrations. Individuals with the Gc2-2 haplotype (rs4588AA/rs7041TT) had statistically significantly lower 25(OH)D concentrations compared to all other Gc haplotypes (p-trend<0.001). The majority of participants (86%) had 25(OH)D concentrations ≥50 nmol/L, which is consistent with the 2011 Institute of Medicine (United States) recommendation for bone health, and 32% had concentrations of ≥75 nmol/L that are thought to be required for broader health effects. Dietary vitamin D intake, hours spent indoors at work, and genetic variation in CYP2R1, CYP3A4 and GC are significant predictors of 25(OH)D concentrations among Singapore Chinese. PMID:22583563

  4. Effects of vitamin D supplementation during pregnancy on neonatal vitamin D and calcium concentrations: a systematic review and meta-analysis.

    PubMed

    Yang, Na; Wang, Linlin; Li, Zhixia; Chen, Sen; Li, Nan; Ye, Rongwei

    2015-07-01

    We conducted a meta-analysis to review the effects of vitamin D supplementation during pregnancy on neonatal 25-hydroxyvitamin D (25(OH)D) and calcium concentrations. Randomized controlled trials that supplemented subjects with vitamin D2 or D3 during pregnancy and reported cord blood 25(OH)D or calcium concentrations were included. A random-effect model was used to pool the data. Subgroup analyses were performed to explore the sources of heterogeneity. We searched PubMed, Web of Science, and Cochrane Library for relevant publications. Among 1768 publications identified by our search strategy, 13 studies met our inclusion criteria. Cord blood 25(OH)D concentration was significantly increased by maternal vitamin D supplementation (mean difference, 22.48 nmol/L; 95% confidence interval, 15.90-29.06 nmol/L) with high heterogeneity (I2 = 98.8%, P < .0001). No effects on cord blood calcium concentration was reported (mean difference, 0.05 mmol/L; 95% confidence interval, -0.04-0.13 mmol/L). Supplementation regimens and the different control groups may be the major sources of heterogeneity. Vitamin D supplementation during pregnancy can improve cord blood 25(OH)D concentration in women with low 25(OH)D concentration, but does not affect cord blood calcium concentration. Future researches are needed to evaluate the effect of maternal vitamin D supplementation in women with a normal 25(OH)D concentration and explore the combined effects of vitamin D, calcium, and multivitamins.

  5. Antiproliferative action of menadione and 1,25(OH)2D3 on breast cancer cells.

    PubMed

    Marchionatti, Ana M; Picotto, Gabriela; Narvaez, Carmen J; Welsh, Joellen; Tolosa de Talamoni, Nori G

    2009-02-01

    Calcitriol or 1,25(OH)(2)D(3) is a negative growth regulator of MCF-7 breast cancer cells. The growth arrest is due to apoptosis activation, which involves mitochondrial disruption. This effect is blunted in vitamin D resistant cells (MCF-7(DRes) cells). Menadione (MEN), a glutathione (GSH)-depleting compound, may potentiate antitumoral effects of anticancer drugs. The aim of this study was to investigate whether MEN enhances cellular responsiveness of MCF-7 cells to 1,25(OH)(2)D(3). Cells were cultured and treated with different concentrations of 1,25(OH)(2)D(3)+/-MEN or vehicle for 96 h. GSH levels and the activity of antioxidant enzymes were determined by spectrophotometry and ROS production by flow cytometry. Both drugs decreased growth and enhanced ROS in MCF-7 cells, obtaining the maximal effects when 1,25(OH)(2)D(3) was combined with MEN (P<0.01 vs. Control and vs. each compound alone). MCF-7(DRes) cells were not responsive to 1,25(OH)(2)D(3), but the cell proliferation was slightly inhibited by the combined treatment. Calcitriol and MEN separately enhanced antioxidant enzyme activities, but when they were used in combination, the effect was more pronounced (P<0.05 vs. Control and vs. each compound alone). MEN, calcitriol and the combined treatment decreased GSH levels (P<0.05 vs. Control). The data indicate that MEN potentiates the effect of 1,25(OH)(2)D(3) on growth arrest in MCF-7 cells by oxidative stress and increases the activities of antioxidant enzymes, probably as a compensatory mechanism.

  6. Association between Obesity and Serum 25(OH)D Concentrations in Older Mexican Adults

    PubMed Central

    Rontoyanni, Victoria G.; Avila, Jaqueline C.; Kaul, Sapna; Wong, Rebeca; Veeranki, Sreenivas P.

    2017-01-01

    Background: Vitamin D is essential for maintaining bone mineralization and calcium homeostasis, and prevents falls and fractures in older adults. Mexico is undergoing an epidemiologic and demographic transition with increasing obesity rates. The study’s aim was to determine the association of obesity with serum 25-hydroxyvitamin D [25(OH)D] concentrations in older Mexican adults. Methods: Data from 1772 Mexicans, aged ≥50 years, enrolled in a sub-sample of the 3rd wave of the Mexican Health and Aging Study, were included. Serum 25(OH)D concentrations were used to define vitamin D status, and were categorized into tertiles. Body mass index measures were used to categorize older adults into under/normal weight, overweight, and obese groups. Multinomial logistic regression models were used to assess the relationship, adjusting for potential confounders. Results: Approximately 40% and 37% of older Mexican adults were either overweight or obese, respectively. Compared to under/normal weight older Mexicans, obese adults were 1.78 times (95% Confidence Interval (CI) 1.27–2.48) and 1.94 times (95% CI 1.40–2.68) more associated with the first and second tertile concentrations of serum 25(OH)D, respectively. Overweight adults were 1.52 times (95% CI 1.12–2.06) more associated with the second tertile of serum 25(OH)D concentration than under/normal weight adults. Conclusion: Overweight/Obesity was found to be significantly associated with low concentrations of serum 25(OH) in older Mexican adults. PMID:28146127

  7. Impact on Vitamin D2, Vitamin D4 and Agaritine in Agaricus bisporus Mushrooms after Artificial and Natural Solar UV Light Exposure.

    PubMed

    Urbain, Paul; Valverde, Juan; Jakobsen, Jette

    2016-09-01

    Commercial mushroom production can expose mushrooms post-harvest to UV light for purposes of vitamin D2 enrichment by converting the naturally occurring provitamin D2 (ergosterol). The objectives of the present study were to artificially simulate solar UV-B doses occurring naturally in Central Europe and to investigate vitamin D2 and vitamin D4 production in sliced Agaricus bisporus (button mushrooms) and to analyse and compare the agaritine content of naturally and artificially UV-irradiated mushrooms. Agaritine was measured for safety aspects even though there is no rationale for a link between UV light exposure and agaritine content. The artificial UV-B dose of 0.53 J/cm(2) raised the vitamin D2 content to significantly (P < 0.001) higher levels of 67.1 ± 9.9 μg/g dry weight (DW) than sun exposure (3.9 ± 0.8 μg/g dry DW). We observed a positive correlation between vitamin D4 and vitamin D2 production (r(2) = 0.96, P < 0.001) after artificial UV irradiation, with vitamin D4 levels ranging from 0 to 20.9 μg/g DW. The agaritine content varied widely but remained within normal ranges in all samples. Irrespective of the irradiation source, agaritine dropped dramatically in conjunction with all UV-B doses both artificial and natural solar, probably due to its known instability. The biological action of vitamin D from UV-exposed mushrooms reflects the activity of these two major vitamin D analogues (D2, D4). Vitamin D4 should be analysed and agaritine disregarded in future studies of UV-exposed mushrooms.

  8. 1α,25(OH)2D3 differentially regulates miRNA expression in human bladder cancer cells

    PubMed Central

    Ma, Yingyu; Hu, Qiang; Luo, Wei; Pratt, Rachel N.; Glenn, Sean T.; Liu, Song; Trump, Donald L.; Johnson, Candace S.

    2014-01-01

    Bladder cancer is the fourth most commonly diagnosed cancer in men and eighth leading cause of cancer-related death in the US. Epidemiological and experimental studies strongly suggest a role for 1α,25(OH)2D3 in cancer prevention and treatment. The antitumor activities of 1α,25(OH)2D3 are mediated by the induction of cell cycle arrest, apoptosis, differentiation and the inhibition of angiogenesis and metastasis. MiRNAs play important regulatory roles in cancer development and progression. However, the role of 1α,25(OH)2D3 in the regulation of miRNA expression and the potential impact in bladder cancer has not been investigated. Therefore, we studied 1α,25(OH)2D3-regulated miRNA expression profiles in human bladder cancer cell line 253J and the highly tumorigenic and metastatic derivative line 253J-BV by miRNA qPCR panels. 253 J and 253J-BV cells express endogenous vitamin D receptor (VDR) which can be further induced by 1α,25(OH)2D3. VDR target gene 24-hydroxylase was induced by 1α,25(OH)2D3 in both cell lines, indicating functional 1α,25(OH)2D3 signaling. The miRNA qPCR panel assay results showed that 253J and 253J-BV cells have distinct miRNA expression profiles. Further, 1α,25(OH)2D3 differentially regulated miRNA expression profiles in 253J and 253 J-BV cells in a dynamic manner. Pathway analysis of the miRNA target genes revealed distinct patterns of contribution to the molecular functions and biological processes in the two cell lines. In conclusion, 1α,25(OH)2D3 differentially regulates the expression of miRNAs, which may contribute to distinct biological functions, in human bladder 253J and 253J-BV cells. PMID:25263658

  9. A Candidate Reference Measurement Procedure for Quantifying Serum Concentrations of 25-Hydroxyvitamin D3 and 25-Hydroxyvitamin D2 Using Isotope-Dilution Liquid Chromatography-Tandem Mass Spectrometry

    PubMed Central

    Mineva, Ekaterina M.; Schleicher, Rosemary L.; Chaudhary-Webb, Madhulika; Maw, Khin L.; Botelho, Julianne C.; Vesper, Hubert W.; Pfeiffer, Christine M.

    2016-01-01

    The inaccuracy of routine serum 25-hydroxyvitamin D measurements hampers the interpretation of data in patient care and public health research. We developed and validated a candidate reference measurement procedure (RMP) for highly accurate quantitation of two clinically important 25-hydroxyvitamin D metabolites in serum, 25-hydroxyvitamin D2 [25(OH)D2] and 25-hydroxyvitamin D3 [25(OH)D3]. The two compounds of interest together with spiked deuterium-labeled internal standards [d3-25(OH)D2 and d6-25(OH)D3] were extracted from serum via liquid-liquid extraction. The featured isotope-dilution LC-MS/MS method used reversed-phase chromatography and atmospheric pressure chemical ionization in positive ion mode. A pentafluorophenylpropyl-packed UHPLC column together with isocratic elution allowed for complete baseline resolution of 25(OH)D2 and 25(OH)D3 from their structural C-3 isomers within 12 min. We evaluated method trueness, precision, potential interferences, matrix effects, limits of quantitation, and measurement uncertainty. Calibration materials were, or were traceable to, NIST Standard Reference Materials 2972. Within-day and total imprecision (CV) averaged 1.9% and 2.0% for 25(OH)D3, respectively, and 2.4% and 3.5% for 25(OH)D2, respectively. Mean trueness was 100.4% for 25(OH)D3 and 100.3% for 25(OH)D2. The limits of quantitation/limits of detection were 4.61/1.38 nmol/L for 25(OH)D3 and 1.46/0.13 nmol/L for 25(OH)D2. When we compared our RMP results to an established RMP using 40 serum samples, we found a nonsignificant mean bias of 0.2% for total 25(OH)D. This candidate RMP for 25(OH)D metabolites meets predefined method performance specifications (≤5% total CV and ≤1.7% bias) and provides sufficient sample throughput to meet the needs of the Centers for Disease Control and Prevention Vitamin D Standardization Certification Program. PMID:25967149

  10. Early indicators of survival following exposure to mustard gas: Protective role of 25(OH)D.

    PubMed

    Das, Lopa M; Binko, Amy M; Traylor, Zachary P; Duesler, Lori R; Dynda, Scott M; Debanne, Sara; Lu, Kurt Q

    2016-04-25

    The use of sulfur mustard (SM) as a chemical weapon for warfare has once again assumed center stage, endangering civilian and the military safety. SM causes rapid local skin vesication and late-onset systemic toxicity. Most studies on SM rely on obtaining tissue and blood for characterizing burn pathogenesis and assessment of systemic pathology, respectively. However the present study focuses on developing a non-invasive method to predict mortality from high dose skin SM exposure. We demonstrate that exposure to SM leads to a dose dependent increase in wound area size on the dorsal surface of mice that is accompanied by a progressive loss in body weight loss, blood cytopenia, bone marrow destruction, and death. Thus our model utilizes local skin destruction and systemic outcome measures as variables to predict mortality in a novel skin-based model of tissue injury. Based on our recent work using vitamin D (25(OH)D) as an intervention to treat toxicity from SM-related compounds, we explored the use of 25(OH)D in mitigating the toxic effects of SM. Here we show that 25(OH)D offers protection against SM and is the first known demonstration of an intervention that prevents SM-induced mortality. Furthermore, 25(OH)D represents a safe, novel, and readily translatable potential countermeasure following mass toxic exposure.

  11. Influence of vitamin D mushroom powder supplementation on exercise-induced muscle damage in vitamin D insufficient high school athletes.

    PubMed

    Shanely, R Andrew; Nieman, David C; Knab, Amy M; Gillitt, Nicholas D; Meaney, Mary Pat; Jin, Fuxia; Sha, Wei; Cialdella-Kam, Lynn

    2014-01-01

    Incidence of vitamin D deficiency is increasing worldwide. The purpose of this study was to determine if supplementation with vitamin D2 from Portobello mushroom powder would enhance skeletal muscle function and attenuate exercise-induced muscle damage in low vitamin D status high school athletes. Participants were randomised to Portobello mushroom powder (600 IU/d vitamin D2) or placebo for 6 weeks. Participants then completed a 1.5-h exercise session designed to induce skeletal muscle damage. Blood samples and measures of skeletal muscle function were taken pre-supplementation, post-supplementation/pre-exercise and post-exercise. Six weeks supplementation with vitamin D2 increased serum 25(OH)D2 by 9.9-fold and decreased serum 25(OH)D3 by 28%. Changes in skeletal muscle function and circulating markers of skeletal muscle damage did not differ between groups. In conclusion, 600 IU/d vitamin D2 increased 25(OH)D2 with a concomitant decrease in 25(OD)D3, with no effect on muscular function or exercise-induced muscle damage in high school athletes.

  12. Impact of sulfur and vitamin C on the allergenicity of Mal d 2 from apple (Malus domestica).

    PubMed

    Marzban, Gorji; Kinaciyan, Tamar; Maghuly, Fatemeh; Brunner, Richard; Gruber, Clemens; Hahn, Rainer; Jensen-Jarolim, Erika; Laimer, Margit

    2014-07-30

    Mal d 2 is a minor allergen from apple which shows a high conformational stability due to its eight conserved disulfide bridges. Chemical reduction of disulfide bridges and linearization of Mal d 2 lead to enhanced IgE reactivity in vitro and indicate a higher potential for allergenicity. Since food preservatives such as sulfur and vitamin C are reducing and denaturing agents, their influence on Mal d 2 allergenicity was verified by simulated food processing conditions. The immunoreactivity of purified Mal d 2 was investigated after different treatments in vitro and in vivo using IgG/IgE Western blotting, mediator-releasing cell assay, and skin prick and oral smear tests. The conformational changes of Mal d 2 upon addition of 1% and 5% vitamin C were also monitored by attenuated total reflectance Fourier transform infrared spectroscopy. The results show no positive skin and oral smear test reactivity to native, heated, or vitamin C-treated purified Mal d 2. Furthermore, the results confirm that sulfur in combination with heat treatment can influence the structural integrity and thus the allergenicity of Mal d 2, while vitamin C is too weak as a reducing agent to change allergenicity.

  13. Correction of vitamin D deficiency using sublingually administered vitamin D2 in a Crohn's disease patient with mal-absorption and a new ileostomy.

    PubMed

    McCullough, Patrick; Heaney, Robert

    2016-12-31

    Vitamin D deficiency has been shown to be associated with many adverse health problems. Studies have shown that patients with Crohn's disease who have low vitamin D levels have a poorer quality of life than those with more adequate levels. It has also been shown that patients with mal-absorption problems have a difficult time achieving normal vitamin D levels in spite of aggressive supplementation, and that exposure to UVB radiation may be the most effective treatment option for these patients. We present a case in which 25-hydroxyvitamin D levels were normalized within 2 weeks in a severely vitamin D deficient patient with Crohn's disease with mal-absorption and a new ileostomy, utilizing sublingually administered vitamin D2. A 58 year-old white female was admitted with a new ileostomy following partial bowel resection due to complications from Crohn's disease. She was found to be severely vitamin D deficient at the time of admission, with a level of 6.1ng/ml on hospital day 3. Her treatment with vitamin D was delayed for a few days. She was initially treated with 5000 units of vitamin D3 orally twice a day for 3days (days 7-10). After discussion with the patient and obtaining her consent, vitamin D3 was stopped, and she was then treated with a total of 8 doses of 50,000 units of vitamin D2 administered sublingually. She was given the first 3 doses on alternating days (days 11, 13, 15), and then 5 more doses on consecutive days (days 17-21). The rise in her 25-hydroxyvitamin D level in response to treatment with sublingual vitamin D2 was significant. On day 10, after receiving 3days of orally administered vitamin D3, her level was 9.8ng/ml. One week later, after receiving 3 sublingual doses of vitamin D2, it rose to 20.3ng/ml. It was then measured on alternating days twice over the next 4days, and it rose to 45.5ng/ml, and then to 47.4ng/ml on the day of discharge to home. The major finding of this study is that sublingual administration of vitamin D2 appears to

  14. Vitamin D status predicts reproductive fitness in a wild sheep population

    PubMed Central

    Handel, Ian; Watt, Kathryn A.; Pilkington, Jill G.; Pemberton, Josephine M.; Macrae, Alastair; Scott, Philip; McNeilly, Tom N.; Berry, Jacqueline L.; Clements, Dylan N.; Nussey, Daniel H.; Mellanby, Richard J.

    2016-01-01

    Vitamin D deficiency has been associated with the development of many human diseases, and with poor reproductive performance in laboratory rodents. We currently have no idea how natural selection directly acts on variation in vitamin D metabolism due to a total lack of studies in wild animals. Here, we measured serum 25 hydroxyvitamin D (25(OH)D) concentrations in female Soay sheep that were part of a long-term field study on St Kilda. We found that total 25(OH)D was strongly influenced by age, and that light coloured sheep had higher 25(OH)D3 (but not 25(OH)D2) concentrations than dark sheep. The coat colour polymorphism in Soay sheep is controlled by a single locus, suggesting vitamin D status is heritable in this population. We also observed a very strong relationship between total 25(OH)D concentrations in summer and a ewe’s fecundity the following spring. This resulted in a positive association between total 25(OH)D and the number of lambs produced that survived their first year of life, an important component of female reproductive fitness. Our study provides the first insight into naturally-occurring variation in vitamin D metabolites, and offers the first evidence that vitamin D status is both heritable and under natural selection in the wild. PMID:26757805

  15. [Is daily supplementation with vitamin D2 equivalent to daily supplementation with vitamin D3 in the elderly?].

    PubMed

    Seijo, Mariana; Mastaglia, Silvina; Brito, Graciela; Somoza, Julia; Oliveri, Beatriz

    2012-01-01

    The equivalence of cholecalciferol (D3) and ergocalciferol (D2) as well as their corresponding doses and administration route remain controversial to date. The aim of this study was to compare the effectiveness of daily supplementation with 800 IU of D2 (drops) and D3 (pills) on 25-hydroxivitamin D (25OHD) levels (= 30 ng/ml). Twenty-one ambulatory postmenopausal women from Buenos Aires City with a mean (X ± SD) age of 77.1 ± 6.8 years were included. The participants were randomly assigned to one of the following groups: GD2 (n = 13): 800 IU (drops) and GD3 (n = 8): 800 IU (pills). Serum 25OHD levels were measured (RIA-DIASORIN) at baseline, and at 7, 28 and 45 days. Nineteen out of twenty one women showed deficient levels of 25OHD at baseline (< 20 ng/ml): GD2: 14.0 ± 4.8 ng/ml and GD3: 13.2 ± 4.9 ng/ml (NS). Whereas only GD3 exhibited an increase (≈ 25%) at 7 days, both groups showed a significant increase at the end of the study. However, neither attained adequate 25OHD levels (GD2: 17.4 ± 5.5 vs. GD3:22.9 ± 4.6 ng/ml; p < 0.001). Administration of 800 IU of vitamin D3 during 45 days was more effective than D2 in increasing 25OHD, but both failed to achieve adequate levels of 25OHD (= 30 ng/ml). but neither succeeded in achieving adequate levels of 25OHD (= 30 ng/ml).

  16. Modeling the sssociation between 25[OH]D and all-cause mortality in a representative US population sample

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vitamin D has been identified as a potential key risk factor for several chronic diseases and mortality. The association between all-cause mortality and circulating levels of 25-ydroxyvitamin D (25[OH]D) has been described as non-monotonic with excess mortality at both low and high levels (1). Howev...

  17. 1,25 (OH)2D3 treatment alters the granulomatous response in M. tuberculosis infected mice

    PubMed Central

    Bhatt, Kamlesh; Rafi, Wasiulla; Shah, Neel; Christakos, Sylvia; Salgame, Padmini

    2016-01-01

    Induction of cathelicidin-mediated antimicrobial pathway against intracellular M. tuberculosis by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), the active form of vitamin D, has been documented in vitro. However, in in vivo studies related to inflammatory disorders, 1,25(OH)2D3 has been demonstrated to induce an anti-inflammatory response. We therefore examined whether in the murine model of tuberculosis, the anti-inflammatory effects of 1,25(OH)2D3 would affect the outcome of M. tuberculosis infection. We show here that administration of 1,25(OH)2D3 to M. tuberculosis infected mice led to a change in lung granuloma architecture, characterized by a marked decrease in B cell lymphocytic aggregates. Consistent with the altered granulomas, 1,25(OH)2D3-treated mice also exhibited significantly higher bacterial burden in the lungs compared to the control group. These findings highlight the need to further investigate the effect of vitamin D on host immunity to M. tuberculosis in the context of the granulomatous response. PMID:27698450

  18. An alternative pathway of vitamin D metabolism. Cytochrome P450scc (CYP11A1)-mediated conversion to 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2.

    PubMed

    Slominski, Andrzej; Semak, Igor; Wortsman, Jacobo; Zjawiony, Jordan; Li, Wei; Zbytek, Blazej; Tuckey, Robert C

    2006-07-01

    We report an alternative, hydroxylating pathway for the metabolism of vitamin D2 in a cytochrome P450 side chain cleavage (P450scc; CYP11A1) reconstituted system. NMR analyses identified solely 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2 derivatives. 20-Hydroxyvitamin D2 was produced at a rate of 0.34 mol x min(-1) x mol(-1) P450scc, and 17,20-dihydroxyvitamin D2 was produced at a rate of 0.13 mol x min(-1) x mol(-1). In adrenal mitochondria, vitamin D2 was metabolized to six monohydroxy products. Nevertheless, aminoglutethimide (a P450scc inhibitor) inhibited this adrenal metabolite formation. Initial testing of metabolites for biological activity showed that, similar to vitamin D2, 20-hydroxyvitamin D2 and 17,20-dihydroxyvitamin D2 inhibited DNA synthesis in human epidermal HaCaT keratinocytes, although to a greater degree. 17,20-Dihydroxyvitamin D2 stimulated transcriptional activity of the involucrin promoter, again to a significantly greater extent than vitamin D2, while the effect of 20-hydroxyvitamin D2 was statistically insignificant. Thus, P450scc can metabolize vitamin D2 to generate novel products, with intrinsic biological activity (at least in keratinocytes).

  19. Vitamin D2 Formation from Post-Harvest UV-B Treatment of Mushrooms (Agaricus bisporus) and Retention during Storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objectives of this research were to study the effects of high intensity (0.5, 0.75, and 1.0 mW/cm2), dose (0.5, 1.0, and 1.5 J/cm2), and post-harvest time (1 and 4 days) on the vitamin D2 formation in Portabella mushrooms (Agaricus bisporus) as a result of UV-B exposure, as well as the vitamin D...

  20. 1α,25(OH)2D3 differentially regulates miRNA expression in human bladder cancer cells.

    PubMed

    Ma, Yingyu; Hu, Qiang; Luo, Wei; Pratt, Rachel N; Glenn, Sean T; Liu, Song; Trump, Donald L; Johnson, Candace S

    2015-04-01

    Bladder cancer is the fourth most commonly diagnosed cancer in men and eighth leading cause of cancer-related death in the US. Epidemiological and experimental studies strongly suggest a role for 1α,25(OH)2D3 in cancer prevention and treatment. The antitumor activities of 1α,25(OH)2D3 are mediated by the induction of cell cycle arrest, apoptosis, differentiation and the inhibition of angiogenesis and metastasis. miRNAs play important regulatory roles in cancer development and progression. However, the role of 1α,25(OH)2D3 in the regulation of miRNA expression and the potential impact in bladder cancer has not been investigated. Therefore, we studied 1α,25(OH)2D3-regulated miRNA expression profiles in human bladder cancer cell line 253J and the highly tumorigenic and metastatic derivative line 253J-BV by miRNA qPCR panels. 253J and 253J-BV cells express endogenous vitamin D receptor (VDR), which can be further induced by 1α,25(OH)2D3. VDR target gene 24-hydroxylase was induced by 1α,25(OH)2D3 in both cell lines, indicating functional 1α,25(OH)2D3 signaling. The miRNA qPCR panel assay results showed that 253J and 253J-BV cells have distinct miRNA expression profiles. Further, 1α,25(OH)2D3 differentially regulated miRNA expression profiles in 253J and 253J-BV cells in a dynamic manner. Pathway analysis of the miRNA target genes revealed distinct patterns of contribution to the molecular functions and biological processes in the two cell lines. In conclusion, 1α,25(OH)2D3 differentially regulates the expression of miRNAs, which may contribute to distinct biological functions, in human bladder 253J and 253J-BV cells. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  1. Statistical Optimization of Ultraviolet Irradiate Conditions for Vitamin D2 Synthesis in Oyster Mushrooms (Pleurotus ostreatus) Using Response Surface Methodology

    PubMed Central

    Wu, Wei-Jie; Ahn, Byung-Yong

    2014-01-01

    Response surface methodology (RSM) was used to determine the optimum vitamin D2 synthesis conditions in oyster mushrooms (Pleurotus ostreatus). Ultraviolet B (UV-B) was selected as the most efficient irradiation source for the preliminary experiment, in addition to the levels of three independent variables, which included ambient temperature (25–45°C), exposure time (40–120 min), and irradiation intensity (0.6–1.2 W/m2). The statistical analysis indicated that, for the range which was studied, irradiation intensity was the most critical factor that affected vitamin D2 synthesis in oyster mushrooms. Under optimal conditions (ambient temperature of 28.16°C, UV-B intensity of 1.14 W/m2, and exposure time of 94.28 min), the experimental vitamin D2 content of 239.67 µg/g (dry weight) was in very good agreement with the predicted value of 245.49 µg/g, which verified the practicability of this strategy. Compared to fresh mushrooms, the lyophilized mushroom powder can synthesize remarkably higher level of vitamin D2 (498.10 µg/g) within much shorter UV-B exposure time (10 min), and thus should receive attention from the food processing industry. PMID:24736742

  2. 77 FR 52228 - Food Additives Permitted for Direct Addition to Food for Human Consumption; Vitamin D2

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-29

    ... HUMAN SERVICES Food and Drug Administration 21 CFR Part 172 Food Additives Permitted for Direct Addition to Food for Human Consumption; Vitamin D2 Bakers Yeast AGENCY: Food and Drug Administration, HHS. ACTION: Final rule. SUMMARY: The Food and Drug Administration (FDA) is amending the food...

  3. Effect of vitamins D2 and D3 supplement use on serum 25OHD concentration in elderly women in summer and winter.

    PubMed

    Rapuri, P B; Gallagher, J C; Haynatzki, G

    2004-02-01

    Vitamin D2 and D3 are generally considered equipotent in humans. A few studies have reported that serum 25OHD levels are higher in vitamin D3- compared with vitamin D2-supplemented subjects. As both vitamin D2 and D3 supplements are commonly used by elderly in United States, in the present study we determined the effect of self-reported vitamin D2 and vitamin D3 supplement use on serum total 25OHD levels according to season in elderly women aged 65-77 years. Serum total 25OHD levels were determined in winter and summer in unsupplemented women ( N = 307) and in women who reported taking vitamin D2 ( N = 56) and vitamin D3 ( N = 55) supplements by competitive protein binding assay. In vitamin D2-supplemented women, the contribution of vitamin D2 and D3 to the mean serum total 25OHD level was assessed by HPLC. In summer, there were no significant differences in the mean total serum 25OHD levels (ng/ml) among the vitamin D2 (32 +/- 2.1), vitamin D3 (36.7 +/- 1.95), and unsupplemented (32.2 +/- 0.95) groups. In winter, the mean serum total 25OHD levels were higher in women on vitamin D2 (33.6 +/- 2.34, P < 0.05) and vitamin D3 (29.7 +/- 1.76, NS) supplements compared with unsupplemented women (27.3 +/- 0.72). In vitamin D2-supplemented women, about 25% of the mean serum total 25OHD was 25OHD2, in both summer and winter. Twelve percent of unsupplemented women and 3.6% of vitamin D-supplemented women had a mean serum total 25OHD level below 15 ng/ml in winter. In elderly subjects, both vitamin D2 and Vitamin D3 supplements may contribute equally to circulating 25OHD levels, with the role of vitamin D supplement use being more predominant during winter.

  4. Vitamin D in adipose tissue and serum 25-hydroxyvitamin D after roux-en-Y gastric bypass.

    PubMed

    Pramyothin, Pornpoj; Biancuzzo, Rachael M; Lu, Zhiren; Hess, Donald T; Apovian, Caroline M; Holick, Michael F

    2011-11-01

    Vitamin D is stored in body fat. The purpose of this study was to determine vitamin D concentration in abdominal fat of obese patients who underwent roux-en-Y gastric bypass (RYGB), and to describe changes in serum 25-hydroxyvitamin D (25(OH)D) levels in relation to loss of body fat. Subjects from a single clinic who were scheduled for RYGB were invited into the study. Abdominal subcutaneous, omental, and mesenteric fat were obtained at time of surgery. Adipose vitamin D(2) and vitamin D(3) concentrations were measured by high-performance liquid chromatography (HPLC). Weight and serum 25(OH)D were assessed at baseline and every 3 months up to 1 year. Seventeen subjects were included, and fat samples were available from eleven. Total vitamin D content in subcutaneous abdominal fat was 297.2 ± 727.7 ng/g tissue, and a wide range was observed (4-2,470 ng/g). Both vitamin D(2) and vitamin D(3) were detected in some of the fat samples. At baseline, 25(OH)D was 23.1 ± 12.6 ng/ml. Average weight loss was 54.8 kg at 12 months, of which ~40 kg was fat mass. Despite daily vitamin D intake of ≥2,500 IU throughout the study, no significant increase in serum 25(OH)D was observed, with mean serum concentration of 25(OH)D at 1 year of 26.2 ± 5.36 ng/ml (P = 0.58). We conclude that vitamin D in adipose tissue does not significantly contribute to serum 25(OH)D despite dramatic loss of fat mass after RYGB.

  5. Total Vitamin D Assay Comparison of the Roche Diagnostics “Vitamin D Total” Electrochemiluminescence Protein Binding Assay with the Chromsystems HPLC Method in a Population with both D2 and D3 forms of Vitamin D

    PubMed Central

    Abdel-Wareth, Laila; Haq, Afrozul; Turner, Andrew; Khan, Shoukat; Salem, Arwa; Mustafa, Faten; Hussein, Nafiz; Pallinalakam, Fasila; Grundy, Louisa; Patras, Gemma; Rajah, Jaishen

    2013-01-01

    This study compared two methods of assaying the 25-hydroxylated metabolites of cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2). A fully automated electrochemiluminescence assay from Roche Diagnostics and an HPLC based method from Chromsystems were used to measure vitamin D levels in surplus sera from 96 individuals, where the majority has the D2 form of the vitamin. Deming regression, concordance rate, correlation and Altman Bland agreement were performed. Seventy two subjects (75%) had a D2 concentration >10 nmol/L while the remaining twenty four subjects had vitamin D2 concentration of less than 10 nmol/L by HPLC. Overall, the Roche Diagnostics method showed a negative bias of −2.59 ± 4.11 nmol/L on the e602 as compared to the HPLC with a concordance rate of 84%. The concordance rate was 91% in samples with D2 of less than 10 nmol/L and 82% in those with D2 concentration >10 nmol/L. The overall correlation had an r value of 0.77. The r value was higher in samples with D2 levels of less than 10 nmol/L, r = 0.96, as compared to those with D2 values of greater than 10 nmol/L, r = 0.74. The observed bias had little impact on clinical decision and therefore is clinically acceptable. PMID:23525081

  6. Total vitamin D assay comparison of the Roche Diagnostics "Vitamin D total" electrochemiluminescence protein binding assay with the Chromsystems HPLC method in a population with both D2 and D3 forms of vitamin D.

    PubMed

    Abdel-Wareth, Laila; Haq, Afrozul; Turner, Andrew; Khan, Shoukat; Salem, Arwa; Mustafa, Faten; Hussein, Nafiz; Pallinalakam, Fasila; Grundy, Louisa; Patras, Gemma; Rajah, Jaishen

    2013-03-22

    This study compared two methods of assaying the 25-hydroxylated metabolites of cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2). A fully automated electrochemiluminescence assay from Roche Diagnostics and an HPLC based method from Chromsystems were used to measure vitamin D levels in surplus sera from 96 individuals, where the majority has the D2 form of the vitamin. Deming regression, concordance rate, correlation and Altman Bland agreement were performed. Seventy two subjects (75%) had a D2 concentration >10 nmol/L while the remaining twenty four subjects had vitamin D2 concentration of less than 10 nmol/L by HPLC. Overall, the Roche Diagnostics method showed a negative bias of -2.59 ± 4.11 nmol/L on the e602 as compared to the HPLC with a concordance rate of 84%. The concordance rate was 91% in samples with D2 of less than 10 nmol/L and 82% in those with D2 concentration >10 nmol/L. The overall correlation had an r value of 0.77. The r value was higher in samples with D2 levels of less than 10 nmol/L, r = 0.96, as compared to those with D2 values of greater than 10 nmol/L, r = 0.74. The observed bias had little impact on clinical decision and therefore is clinically acceptable.

  7. Vitamin D metabolite concentrations in umbilical cord blood serum and associations with clinical characteristics in a large prospective mother-infant cohort in Ireland.

    PubMed

    Kiely, Mairead; O'Donovan, Sinead M; Kenny, Louise C; Hourihane, Jonathan O'B; Irvine, Alan D; Murray, Deirdre M

    2017-03-01

    Vitamin D deficiency is widespread among mothers and neonates and quality clinical and analytical data are lacking. We used a CDC-accredited LC-MS/MS method to analyze vitamin D metabolites in cord sera from 1050 maternal-infant dyads in the prospective SCOPE Ireland Pregnancy and BASELINE Birth cohort studies, based in Cork, Ireland. The mean±SD total 25(OH)D was 34.9±18.1nmol/L; 35% of cords (50% during winter) had 25(OH)D <25nmol/L, 46% were <30nmol/L and 80% were <50nmol/L. In this predominantly white cohort, the main predictor of cord 25(OH)D [adj. mean difference in nmol/L (95% CI)] was summer delivery [19.2 (17.4, 20.9), P<0.0001]. Maternal smoking during pregnancy (9% prevalence) was negatively associated (P<0.002) with cord 25(OH)D [-4.83 (-7.9, -1.5) nmol/L]. There were no associations between cord 25(OH)D and birth weight or any anthropometric measures at birth. Despite the high prevalence of vitamin D deficiency at birth, there were no documented musculoskeletal complications during infancy, which was likely due to widespread supplementation with vitamin D. The mean±SD concentration of 3-epi-25(OH)D3, detectable in 99.4% of cord samples, was 3.3±1.9nmol/L. The proportion of 25(OH)D as 3-epi-25(OH)D3 was 11.2%. Cord 3-epi-25(OH)D3 concentrations were positively predicted by cord 25(OH)D3 [0.101 (0.099, 0.103) nmol/L, P<0.0001] and negatively by gestational age [-0.104 (-0.131, -0.076) nmol/L, P<0.0001] and maternal age [-0.010 (-0.019, -0.001) nmol/L, P<0.05]. 25(OH)D2 was detected in 98% of cord sera (mean±SD; 2.2±1.9nmol/L) despite low antenatal consumption of vitamin D2 supplements. In conclusion, these first CDC-accredited data of vitamin D metabolites in umbilical cord blood emphasise the high risk of very low vitamin D status in infants born to un-supplemented mothers. Experimental data to define maternal vitamin D requirements for prevention of neonatal deficiency at high latitude are required.

  8. Quantitative determination of vitamin D metabolites in plasma using UHPLC-MS/MS.

    PubMed

    Ding, Shujing; Schoenmakers, Inez; Jones, Kerry; Koulman, Albert; Prentice, Ann; Volmer, Dietrich A

    2010-09-01

    Vitamin D is an important determinant of bone health at all ages. The plasma concentrations of 25-hydroxy vitamin D (25-OH D) and other metabolites are used as biomarkers for vitamin sufficiency and function. To allow for the simultaneous determination of five vitamin D metabolites, 25-OH D(3), 25-OH D(2), 24,25-(OH)(2) D(3), 1,25-(OH)(2) D(3), and 1,25-(OH)(2) D(2), in low volumes of human plasma, an assay using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was established. Plasma samples were spiked with isotope-labeled internal standards and pretreated using protein precipitation, solid-phase extraction (SPE) and a Diels-Alder derivatization step with 4-phenyl-1,2,4-triazoline-3,5-dione. The SPE recovery rates ranged from 55% to 85%, depending on the vitamin D metabolite; the total sample run time was <5 min. Mass spectrometry was conducted using positive ion electrospray ionization in the multiple reaction monitoring mode on a quadrupole-quadrupole-linear ion trap instrument after pre-column addition of methylamine to increase the ionization efficiency. The intra- and inter-day relative standard deviations were 1.6-4.1% and 3.7-6.8%, respectively. The limit of quantitation for these compounds was determined to be between 10 and 20 pg/mL. The 25-OH D results were compared with values obtained for reference materials (DEQAS). In addition, plasma samples were analyzed with two additional Diasorin antibody assays. All comparisons with conventional methods showed excellent correlations (r(2) = 0.9738) for DEQAS samples, demonstrating the high degree of comparability of the new UHPLC-MS/MS technique to existing methods.

  9. Effect of pasteurisation on the concentrations of vitamin D compounds in donor breastmilk.

    PubMed

    Gomes, Fabio P; Shaw, P Nicholas; Whitfield, Karen; Koorts, Pieter; McConachy, Helen; Hewavitharana, Amitha K

    2016-01-01

    Premature infants are the main recipients of pasteurised donor human milk (PDHM), when their mothers are unable to provide their own. In this study, we evaluated the effect of pasteurisation on the concentrations of vitamin D compounds in donor breastmilk. Milk samples were obtained pre- and post-Holder pasteurisation. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to analyse the samples for vitamins D2 and D3 (D2 and D3) and 25-hydroxyvitamins D2 and D3 (25(OH)D2 and 25(OH)D3). The significance of differences in vitamin D concentrations between the two groups of milk samples was assessed using the Wilcoxon matched-pairs signed rank test, in which p < 0.05 was considered significant. Pasteurisation resulted in a significant reduction (p < 0.05) in the content of D2, D3, 25(OH)D2 and 25(OH)D3. The losses ranged from 10% to 20% following pasteurisation.

  10. Vitamin D Metabolism, Mechanism of Action, and Clinical Applications

    PubMed Central

    Bikle, Daniel D.

    2014-01-01

    Vitamin D3 is made in the skin from 7-dehydrocholesterol under the influence of UV light. Vitamin D2 (ergocalciferol) is derived from the plant sterol ergosterol. Vitamin D is metabolized first to 25 hydroxyvitamin D (25OHD), then to the hormonal form 1,25-dihydroxyvitamin D (1,25(OH)2D). CYP2R1 is the most important 25-hydroxylase; CYP27B1 is the key 1-hydroxylase. Both 25OHD and 1,25(OH)2D are catabolized by CYP24A1. 1,25(OH)2D is the ligand for the vitamin D receptor (VDR), a transcription factor, binding to sites in the DNA called vitamin D response elements (VDREs). There are thousands of these binding sites regulating hundreds of genes in a cell-specific fashion. VDR-regulated transcription is dependent on comodulators, the profile of which is also cell specific. Analogs of 1,25(OH)2D are being developed to target specific diseases with minimal side effects. This review will examine these different aspects of vitamin D metabolism, mechanism of action, and clinical application. PMID:24529992

  11. Differential gene expression by 1,25(OH)2D3 in an endometriosis stromal cell line.

    PubMed

    Ingles, Sue Ann; Wu, Liang; Liu, Benjamin T; Chen, Yibu; Wang, Chun-Yeh; Templeman, Claire; Brueggmann, Doerthe

    2017-01-28

    Endometriosis is a common female reproductive disease characterized by invasion of endometrial cells into other organs, frequently causing pelvic pain and infertility. Alterations of the vitamin D system have been linked to endometriosis incidence and severity. To shed light on the potential mechanism for these associations, we examined the effects of 1,25(OH)2D3 on gene expression in endometriosis cells. Stromal cell lines derived from endometriosis tissue were treated with 1,25(OH)2D3, and RNA-seq was used to identify genes differentially expressed between treated and untreated cells. Gene ontology and pathway analyses were carried out using Partek Flow and Ingenuity software suites, respectively. We identified 1627 genes that were differentially expressed (886 down-regulated and 741 up-regulated) by 1,25(OH)2D3. Only one gene, CYP24A1, was strongly up-regulated (369-fold). Many genes were strongly down-regulated. 1,25(OH)2D3 treatment down-regulated several genetic pathways related to neuroangiogenesis, cellular motility, and invasion, including pathways for axonal guidance, Rho GDP signaling, and matrix metalloprotease inhibition. These findings support a role for vitamin D in the pathophysiology of endometriosis, and provide new targets for investigation into possible causes and treatments.

  12. The Effect of Various Vitamin D Supplementation Regimens in Breast Cancer Patients

    PubMed Central

    Peppone, Luke J.; Huston, Alissa J.; Reid, Mary E.; Rosier, Randy N.; Zakharia, Yousef; Trump, Donald L.; Mustian, Karen M.; Janelsins, Michelle C.; Purnell, Jason Q.; Morrow, Gary R.

    2014-01-01

    Purpose Vitamin D deficiency in patients treated for breast cancer is associated with numerous adverse effects (bone loss, arthralgia, and falls). The first aim of this study was to assess vitamin D status, determined by 25-OH vitamin D levels, among women diagnosed with breast cancer according to demographic/clinical variables and bone mineral density (BMD). The second aim of this study was to evaluate the effect of daily low-dose and weekly high-dose vitamin D supplementation on 25-OH vitamin D levels. Methods This retrospective study included 224 women diagnosed with Stage 0-III breast cancer who received treatment at the James P. Wilmot Cancer Center at the University of Rochester Medical Center. Total 25-OH vitamin D levels (D2 + D3) were determined at baseline for all participants. Vitamin D deficiency was defined as a 25-OH vitamin D level < 20 ng/mL, insufficiency as 20-31 ng/mL, and sufficiency as ≥ 32 ng/mL. BMD was assessed during the period between 3 months prior to and 6 months following the baseline vitamin D assessment. Based on the participants’ baseline levels, they received either no supplementation, low-dose supplementation (1,000 IU/day), or high-dose supplementation (≥ 50,000 IU/week), and 25-OH vitamin D was reassessed in the following 8-16 weeks. Results Approx 66.5% had deficient/insufficient vitamin D levels at baseline. Deficiency/insufficiency was more common among non-Caucasians, women with later-stage disease, and those who had previously received radiation therapy (p<0.05). Breast cancer patients with deficient/insufficient 25-OH vitamin D levels had significantly lower lumbar BMD (p=0.03). Compared to the no supplementation group, weekly high-dose supplementation significantly increased 25-OH vitamin D levels, while daily low-dose supplementation did not significantly increase levels. Conclusions Vitamin D deficiency and insufficiency were common among women with breast cancer and associated with reduced BMD in the spine

  13. The effect of various vitamin D supplementation regimens in breast cancer patients

    PubMed Central

    Huston, Alissa J.; Reid, Mary E.; Rosier, Randy N.; Zakharia, Yousef; Trump, Donald L.; Mustian, Karen M.; Janelsins, Michelle C.; Purnell, Jason Q.; Morrow, Gary R.

    2011-01-01

    Vitamin D deficiency in the patients treated for breast cancer is associated with numerous adverse effects (bone loss, arthralgia, and falls). The first aim of this study was to assess vitamin D status, determined by 25-OH vitamin D levels, among women diagnosed with breast cancer according to demographic/clinical variables and bone mineral density (BMD). The second aim of this study was to evaluate the effect of daily low-dose and weekly high-dose vitamin D supplementation on 25-OH vitamin D levels. This retrospective study included 224 women diagnosed with stage 0–III breast cancer who received treatment at the James P. Wilmot Cancer Center at the University of Rochester Medical Center. Total 25-OH vitamin D levels (D2 + D3) were determined at baseline for all participants. Vitamin D deficiency was defined as a 25-OH vitamin D level < 20 ng/ml, insufficiency as 20–31 ng/ml, and sufficiency as ≥32 ng/ml. BMD was assessed during the period between 3 months before and 6 months following the baseline vitamin D assessment. Based on the participants’ baseline levels, they received either no supplementation, low-dose supplementation (1,000 IU/day), or high-dose supplementation (≥50,000 IU/week), and 25-OH vitamin D was reassessed in the following 8–16 weeks. Approximately 66.5% had deficient/insufficient vitamin D levels at baseline. Deficiency/insufficiency was more common among non-Caucasians, women with later-stage disease, and those who had previously received radiation therapy (P < 0.05). Breast cancer patients with deficient/insufficient 25-OH vitamin D levels had significantly lower lumbar BMD (P = 0.03). Compared to the no-supplementation group, weekly high-dose supplementation significantly increased 25-OH vitamin D levels, while daily low-dose supplementation did not significantly increase levels. Vitamin D deficiency and insufficiency were common among women with breast cancer and associated with reduced BMD in the spine. Clinicians should

  14. Accurate and reliable quantification of 25-hydroxy-vitamin D species by liquid chromatography high-resolution tandem mass spectrometry[S

    PubMed Central

    Liebisch, Gerhard; Matysik, Silke

    2015-01-01

    In general, mass spectrometric quantification of small molecules in routine laboratory testing utilizes liquid chromatography coupled to low mass resolution triple-quadrupole mass spectrometers (QQQs). Here we introduce high-resolution tandem mass spectrometry (quadrupole-Orbitrap) for the quantification of 25-hydroxy-vitamin D [25(OH)D], a marker of the vitamin D status, because the specificity of 25(OH)D immunoassays is still questionable and mass spectrometric quantification is becoming increasingly important. Liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-MS/HR-MS) was used to quantify 25-hydroxy-cholecalciferol [25(OH)D3], 25-hydroxy-ergocalciferol [25(OH)D2], and their C3-epimers 3-epi-25(OH)D3 and 3-epi-25(OH)D2. The method has a run time of 5 min and was validated according to the US Food and Drug Administration and the European Medicines Agency guidelines. High mass resolution was advantageously applied to separate a quasi-isobaric interference of the internal standard D6-25(OH)D2 with 3-epi-25(OH)D3. All analytes showed an imprecision of below 10% coefficient of variation (CV), trueness between 90% and 110%, and limits of quantification below 10 nM. Concentrations measured by LC-MS/HR-MS are in good agreement with those of the National Institute of Standards and Technology reference methods using LC-MS/MS (QQQ). In conclusion, quantification of 25(OH)D by LC-MS/HR-MS is applicable for routine testing and also holds promise for highly specific quantification of other small molecules. PMID:25833687

  15. 25(OH)D deficiency is associated with fatal stroke among whites but not blacks: The NHANES-III linked mortality files

    PubMed Central

    Michos, Erin D.; Reis, Jared P.; Post, Wendy S.; Lutsey, Pamela L.; Gottesman, Rebecca F.; Mosley, Thomas H.; Sharrett, A. Richey; Melamed, Michal L.

    2011-01-01

    Objective Deficient 25-hydroxyvitamin D [25(OH)D] levels are associated with cardiovascular disease (CVD) events and mortality. Both 25(OH)D deficiency and stroke are more prevalent among blacks. We examined whether low 25(OH)D contributes to the excess risk of fatal stroke in blacks compared to whites. Research Methods and Procedures The Third National Health and Nutrition Examination Survey, a probability sample of US civilians, measured 25(OH)D levels and CVD risk factors between 1988–1994. Vital status through December 2006 was obtained via linkage with the National Death Index. Among white and black adults without CVD reported at baseline (n=7981), Cox regression models were fit to estimate hazard ratios (HR) for fatal stroke by 25(OH)D status and race. Results During a median of 14.1 years, there were 116 and 60 fatal strokes among whites and blacks respectively. The risk of fatal stroke was greater in blacks compared to whites in models adjusted for socio-economic status and CVD risk factors, [HR 1.60 (95% CI 1.01–2.53)]. Mean baseline 25(OH)D levels were significantly lower in blacks compared to whites (19.4 vs 30.8 ng/mL, respectively). In multivariable-adjusted models, deficient 25(OH)D levels <15 ng/mL were associated with fatal stroke among whites [HR 2.13 (1.01–4.50)] but not blacks [HR 0.93 (0.49–1.80)]. Conclusions Vitamin D deficiency was associated with increased risk of stroke death in whites but not blacks. Although blacks had a higher rate of fatal stroke compared to whites, the low 25(OH)D levels in blacks were unrelated to stroke incidence and therefore 25(OH)D levels did not explain this excess risk. PMID:22261577

  16. The effect of magnesium ions on vitamin D(2)-phospholipid model membrane interactions in the presence of different buffer media.

    PubMed

    Toyran, N; Severcan, F

    2000-10-02

    Vitamin D plays important roles in the bone formation, in calcium and phosphorus homeostasis and in the treatment and prevention of many diseases. Ions, especially divalent cations like Mg(2+), have indispensable roles in many vital biological events. Mg(2+) is involved in many fundamental processes such as stabilization of membranes and macromolecules, synthesis of nucleic acid and proteins and formation and use of high-energy phosphate bonds. Mg(2+) is also required for synthesis of more than 310 different enzymes of the body and is, therefore, involved in many important activities. The roles of vitamin D and major ions in the body are quite well known. While there are still many unresolved points about the exact molecular mechanism behind such diverse functions, in the present study, the interaction of Mg(2+) with dipalmitoyl phosphatidylcholine (DPPC) model membranes has been studied in the presence and absence of vitamin D(2) by using Fourier transform infrared (FTIR) spectroscopy and turbidity technique at 440 nm. The effect of different buffer media on the system has also been investigated. The temperature dependent investigation of the wavelength of the CH(2) antisymmetric stretching bands revealed that, in the presence of N-[2-hydroxyethyl] piperazine-N'-[2-ethanesulfonic acid] (Hepes) and phosphate buffer, addition of Mg(2+) and/or vitamin D(2) into pure DPPC liposomes does not change the shape of the phase transition profile. Turbidity studies support these results. In the presence of Hepes buffer, the inclusion of Mg(2+) and/or vitamin D(2) into pure DPPC liposomes orders the system. In the presence of phosphate buffer, FTIR study showed that, addition of Mg(2+) into pure DPPC liposomes disorders the system in the gel phase. The precipitation of Mg(2+) with phosphates, which is present in phosphate buffer, may be a reason for this difference in the effect. It is seen that, the binary mixture of Mg(2+)-DPPC and the ternary mixture of Mg(2+)-vitamin D(2

  17. Association of Circulating 25(OH)D and Lower Urinary Tract Symptoms: A Four-Year Prospective Study among Elderly Chinese Men

    PubMed Central

    Liu, Zhao-Min; Wong, Carmen Ka Man; Chan, Dicken; Woo, Jean; Chen, Yu-Ming; Chen, Bailing; Tse, Lap-Ah; Wong, Samuel Yeung-Shan

    2016-01-01

    The role of vitamin D in relation to lower urinary tract symptoms (LUTS) remains inconclusive. This four-year longitudinal study aims to explore the association of circulating 25(OH)D and LUTS in elderly Chinese men. Two thousand Chinese men aged 65 and older were recruited from a local community, of which 1998 (99.9%) at baseline and 1564 (78.2%) at four-year follow-up reported data on LUTS, and 988 of the randomly chosen subpopulation were assayed for serum 25(OH)D by radioimmunoassay at baseline. LUTS were evaluated by a validated International Prostate Symptoms Scale (IPSS). Data on demographic characteristics, lifestyle factors, health, and medications were collected. Serum parathyroid and sex steroid hormones and genotypes of vitamin D receptors were assayed. The association of serum 25(OH)D and LUTS was examined by using multivariable regression models. Serum 25(OH)D was not significantly associated with the changes of IPSS or the risk of LUTS in overall participants. However, among men with 25(OH)D ≤ 60 nmol/L, each 10 nmol/L increase of 25(OH)D over 0 nmol/L was significantly associated with 1.3 lower points of IPSS or a 51.6% decreased risk for moderate/severe LUTS four years later. Adjustment for serum androstenedione (p = 0.019) and dehydropiandrosterone (p = 0.037) attenuated the associations. Our study suggested that among individuals with low vitamin D status, the increase of the 25(OH)D level may be associated with a lowered risk of LUTS. PMID:27164139

  18. The effect of vitamin D2 and vitamin D3 on intestinal calcium absorption in Nigerian children with rickets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Children with calcium-deficiency rickets have high 1,25-dihydroxyvitamin D values. The objective of the study was to determine whether vitamin D increased calcium absorption. This was an experimental study. The study was conducted at a teaching hospital. Participants included 17 children with nutrit...

  19. Vitamin D-induced ectodomain shedding of TNF receptor 1 as a nongenomic action: D3 vs D2 derivatives.

    PubMed

    Yang, Won Seok; Yu, Hoon; Kim, Jin Ju; Lee, Mee Jeong; Park, Su-Kil

    2016-01-01

    As a nongenomic action, 1,25-dihydroxyvitamin D3 (1,25D3) induces L-type Ca(2+) channel-mediated extracellular Ca(2+) influx in human aortic smooth muscle cells (HASMCs), which activates a disintegrin and metalloprotease 10 (ADAM10) to cleave and shed the ectodomain of tumor necrosis factor receptor 1 (TNFR1). In this study, we examined the potencies of other vitamin D3 and D2 analogs to stimulate the ectodomain shedding of TNFR1 in HASMCs. 25-Hydroxyvitamin D3 (25D3), a precursor of 1,25D3, and elocalcitol, an analog of 1,25D3, caused ectodomain shedding of TNFR1 within 30 min, whereas 1,25-dihydroxyvitamin D2 (1,25D2) and paricalcitol, a derivative of 1,25D2, did not. Both 25D3 and elocalcitol rapidly induced extracellular Ca(2+) influx and markedly increased intracellular Ca(2+), while 1,25D2 and paricalcitol caused only small increases in intracellular Ca(2+). 25D3- and elocalcitol-induced TNFR1 ectodomain sheddings were abolished by verapamil and in Ca(2+)-free media. Both 25D3 and elocalcitol caused the translocation of ADAM10 to the cell surface, which was inhibited by verapamil, while 1,25D2 and paricalcitol did not cause ADAM10 translocation. When ADAM10 was depleted by ADAM10-siRNA, 25D3 and elocalcitol could not induce ectodomain shedding of TNFR1. The plasma membrane receptor, endoplasmic reticulum stress protein 57 (ERp57), but not the classic vitamin D receptor, mediated the nongenomic action of vitamin D to induce ectodomain shedding of TNFR1. In summary, like 1,25D3, 25D3 and elocalcitol caused ADAM10-mediated ectodomain shedding of TNFR1, whereas 1,25D2 and paricalcitol did not. The difference may depend on their affinities to ERp57 through which extracellular Ca(2+) influx is induced.

  20. The Correlation Between Serum Vitamin D Deficiency and Preterm Birth

    PubMed Central

    Yang, Lixia; Pan, Shilei; Zhou, Yufeng; Wang, Xiaoyang; Qin, Aikai; Huang, Yuxin; Sun, Suxia

    2016-01-01

    Background Preterm birth is an important cause of death and developmental disorder in neonates. Vitamin D deficiency has been shown to regulate body inflammatory factor levels that stimulate elevation of uterine contraction hormones, such as prostaglandin, thus causing preterm birth. However, current observations regarding the relationship between vitamin D and preterm birth are inconsistent. We performed a nested case-control study to investigate the effect of vitamin D on preterm birth. Material/Methods A prospective cohort study included 200 cases of pregnant women in our hospital from May 2013 to May 2015. Blood samples were collected from early, middle, and late stages of pregnancy. Forty-six patients with preterm delivery were compared with age-matched full-term delivery cases (N=92). High performance liquid chromatography-mass spectrometry (HPLC-MS) was used to detect serum levels of 25(OH)D, 25(OH)D2, and 25(OH)D3. Logistic regression was performed to analyze the correlation between 25(OH)D and risk of preterm birth. Results No significant difference in age, smoking/drinking, education level, BMI and vitamin D levels was found between the preterm birth group and full-term delivery group. No significant difference was found for vitamin D levels across different stages of pregnancy; no difference in concentration of 25(OH)D related to preterm birth risk was found. After adjusting for potentially confounding factors, serum vitamin D level did not increase the risk of preterm birth. Conclusions This study did not found evidence of an increase in preterm birth risk related to vitamin D level during pregnancy. PMID:27851719

  1. Analysis of vitamin D and its metabolites using thermospray liquid chromatography/mass spectrometry.

    PubMed

    Watson, D; Setchell, K D; Ross, R

    1991-07-01

    A new method is described for the analysis of vitamin D and its metabolites utilizing thermospray (TSP) mass spectrometry as an on-line detector for high performance liquid chromatography. Ionization conditions were optimized for use with isocratic reversed phase chromatography. TSP mass spectrometry was employed in series with a UV absorbance detector to facilitate comparisons between the two methods of detection. Positive ion TSP mass spectra were recorded for vitamin D2, vitamin D3, 25-hydroxyvitamin D3 (25(OH)D3), 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) and 24,25-dihydroxyvitamin D3 (24,25(OH)2D3). The spectra contained protonated molecular ions, ammonium adduct ions and fragment ions due to the loss of one or more molecules of water. A comparison of quantitative precision was made by determining UV absorbance and TSP standard curves for vitamin D3 using two different methods: (1) External standard method with post-column (post UV detector) addition of ammonium acetate. (2) As (1) but using the method of internal standards with a closely eluting internal standard (vitamin D2). In each case the quantitative precision (correlation coefficient) for UV absorbance detection was superior owing to intrinsic instability of the TSP ion beam. A stable isotopically labelled internal standard was employed in the development of an assay for 1,25(OH)2D3. The assay was used to quantify in vitro enzymic conversion of 25(OH)D3 to 1,25(OH)2D3 in guinea pig and sheep renal mitochondrial incubations. TSP LC/MS was also applied to analysis of an extract of human blood plasma in which D3 and each of its principal metabolites were identified in a single analysis.

  2. Vitamin D: present and future.

    PubMed

    Varsavsky, M; Alonso, G; García-Martín, A

    2014-10-01

    In recent years has been a growing interest by vitamin D, not only for its important role in the bone mineral metabolism, but also by the extra-osseous effects. Most of the scientific societies consider that deposits are sufficient if the serum concentration of 25-OH vitamin D is above 30ng/ml and are considered deficient if levels are below 20ng/ml. The majority of studies found that supplements of calcium plus vitamin D have a positive effect in reducing the risk of fracture and the risk of falls in the elderly, although several specifies that doses should be 700-1.000 IU daily. The treatment of the deficit can be performed with vitamin D2, D3 as well as calcidiol or the active metabolite calcitriol. In certain pathologies also selective vitamin D receptor activators can be used.

  3. Method evaluation study of a new generation of vitamin D assays

    PubMed Central

    Kriegshäuser, Gernot; Stolba, Robert; Worf, Elfriede; Halwachs-Baumann, Gabriele

    2015-01-01

    Introduction Recently several diagnostic manufacturers have launched new 25-hydroxy-vitamin D (25[OH]D) assays, which are aligned to the National Institute of Standards and Technology (NIST) Standard Reference Materials (SRM) (NIST, Gaithersburg, Maryland). The aim of this study was to compare the performance of one liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, one enzyme linked immunosorbent assay (ELISA), and one recalibrated and previous version of a chemiluminescence immunoassay (CLIA). Material and methods Serum-aliquots of 198 patient samples from routine 25(OH)D analysis were measured by the ClinMass® LC-MS/MS Complete Kit (RECIPE Chemicals + Instruments GmbH, Munich, Germany), the ORGENTEC 25(OH)D3/D2 ELISA (ORGENTEC Diagnostika GmbH, Mainz, Germany), the recalibrated Immunodiagnostic Systems (IDS)-iSYS 25(OH)DS and the previous used IDS-iSYS 25(OH)D CLIA (Immunodiagnostic Systems Ltd, Boldon, United Kingdom). Bland-Altman and Deming regression analyses were calculated for methods comparison of all tested 25(OH)D assays. The LC-MS/MS method was defined as the reference method. Within-run and between-run precision measurements were performed for all methods with three different concentration levels. Results Compared to the LC-MS/MS method, the new IDS-iSYS 25(OH)DS and ORGENTEC 25(OH)D3/D2 assay demonstrated mean relative biases of 16.3% and 17.8%. The IDS-iSYS 25(OH)D assay showed the lowest mean bias of 1.5%. Deming regression analyses of the recalibrated IDS-iSYS 25(OH)DS and the ORGENTEC 25(OH)D3/D2 assay showed proportional differences, when compared to the reference method. All assays showed a within-run and between-run imprecision of ≤ 20% at each of the evaluated concentration levels. Conclusions The evaluated standardized immunoassays and LC-MS/MS are useful methods for measuring 25(OH)D serum-levels in clinical laboratories. PMID:26110032

  4. Vitamin D 2 interacts with Human PrP(c) (90-231) and breaks PrP(c) oligomerization in vitro.

    PubMed

    Suenaga, Midori; Hiramoto, Yusuke; Matsunaga, Yoichi

    2013-01-01

    PrP(sc), the pathogenic isoform of PrP(c), can convert PrP(c) into PrP(sc) through direct interactions. PrP(c) oligomerization is a required processing step before PrP(sc) formation, and soluble oligomers appear to be the toxic species in amyloid-related disorders. In the current study, direct interactions between vitamin D 2 and human recombinant PrP(c) (90-231) were observed by Biacore assay, and 3F4 antibody, specific for amino acid fragment 109-112 of PrP(c), inhibited this interaction. An ELISA study using3F4 antibody showed that PrP(c) (101-130), corresponding sequence to human PrP, was affected by vitamin D 2, supporting the results of Biacore studies and suggesting that the PrP(c) sequence around the 3F4 epitope was responsible for the interaction with vitamin D 2. Furthermore, the effects of vitamin D 2 on disruption of PrP(c) (90-231) oligomerization were elucidated by dot blot analysis and differential protease k susceptibilities. While many chemical compounds have been proposed as potential therapeutic agents for the treatment of scrapie, most of these are toxic. However, given the safety and blood brain barrier permeability of vitamin D 2, we propose that vitamin D 2 may be a suitable agent to target PrP(c) in the brain and therefore is a potential therapeutic candidate for prion disease.

  5. Genetic Ancestry, Skin Reflectance and Pigmentation Genotypes in Association with Serum Vitamin D Metabolite Balance

    PubMed Central

    Wilson, Robin Taylor; Roff, Alanna N.; Dai, P. Jenny; Fortugno, Tracey; Douds, Jonathan; Chen, Gang; Grove, Gary L.; Nikiforova, Sheila Ongeri; Barnholtz-Sloan, Jill; Frudakis, Tony; Chinchilli, Vernon M.; Hartman, Terryl J.; Demers, Laurence M.; Shriver, Mark D.; Canfield, Victor A.; Cheng, Keith C.

    2012-01-01

    Background Lower serum vitamin D (25(OH)D) among individuals with African ancestry is attributed primarily to skin pigmentation. However, the influence of genetic polymorphisms controlling for skin melanin content has not been investigated. Therefore, we investigated differences in non-summer serum vitamin D metabolites according to self-reported race, genetic ancestry, skin reflectance and key pigmentation genes (SLC45A2 and SLC24A5). Materials and Methods Healthy individuals reporting at least half African American or half European American heritage were frequency matched to one another on age (+/− 2 years) and sex. 176 autosomal ancestry informative markers were used to estimate genetic ancestry. Melanin index was measured by reflectance spectrometry. Serum vitamin D metabolites (25(OH)D3, 25(OH)D2 and 24,25(OH)2D3) were determined by high performance liquid chromatography (HPLC) tandem mass spectrometry. Percent 24,25(OH)2D3 was calculated as a percent of the parent metabolite (25(OH)D3). Stepwise and backward selection regression models were used to identify leading covariates. Results Fifty African Americans and 50 European Americans participated in the study. Compared with SLC24A5 111Thr homozygotes, individuals with the SLC24A5 111Thr/Ala and 111Ala/Ala genotypes had respectively lower levels of 25(OH)D3 (23.0 and 23.8 nmol/L lower, p-dominant=0.007), and percent 24,25(OH)2D3 (4.1 and 5.2 percent lower, p-dominant=0.003), controlling for tanning bed use, vitamin D/fish oil supplement intake, race/ethnicity, and genetic ancestry. Results were similar with melanin index adjustment, and were not confounded by glucocorticoid, oral contraceptive, or statin use. Conclusions The SLC24A5 111Ala allele was associated with lower serum vitamin 25(OH)D3 and lower percent 24,25(OH)2D3, independently from melanin index and West African genetic ancestry. PMID:23525585

  6. High-performance liquid chromatographic determination of vitamin D3 in fish liver oils and eel body oils.

    PubMed

    Takeuchi, A; Okano, T; Ayame, M; Yoshikawa, H; Teraoka, S; Murakami, Y; Kobayashi, T

    1984-10-01

    Identification and determination of vitamin D3 (or D2) and 25-OH-D3 in fish liver oils and eel body oils were carried out. By co-chromatography on HPLC, UV spectra and/or GC-MS, vitamin D3 was identified in naturally occurring fish liver oils and eel body oils, whereas a drop of fish liver oil contained supplemented vitamin D2. 25-OH-D3 was identified only in skipjack liver oil. The HPLC method proposed in a previous report (Takeuchi, A. et al. (1984): J. Nutr. Sci. Vitaminol., 30, 11-25) was confirmed to also be useful for determination of vitamin D3 (or D2) in fish liver oils and eel body oils. The assayed values of vitamin D3 in skipjack and tuna liver oils were 57,760 and 16,200 IU/g, respectively, which were much higher than those in cod and pollack liver oils. The assayed values of vitamin D3 in eel body oils were very low (16-43 IU/g) and showed no appreciable change despite differences in the farming conditions. Determination of 25-OH-D3 in skipjack oil was performed by using HPLC, and the assayed value was 1.8 micrograms/g. This was about 1/800 lower than that of vitamin D3.

  7. Association between 25(OH)D Level, Ultraviolet Exposure, Geographical Location, and Inflammatory Bowel Disease Activity: A Systematic Review and Meta-Analysis

    PubMed Central

    Lu, Chao; Yang, Jun; Yu, Weilai; Li, Dejian; Xiang, Zun; Lin, Yiming; Yu, Chaohui

    2015-01-01

    Background There is no consensus on the vitamin D levels and inflammatory bowel disease (IBD). Aim To conduct a systematic review and meta-analysis to analyze the relationship between IBD and 25(OH)D, sun exposure, and latitude, and to determine whether vitamin D deficiency affects the severity of IBD. Methods We searched the PubMed, EBSCO, and ClinicalTrials.gov databases to identify all studies that assessed the association between 25(OH)D, sun exposure, latitude, and IBD through November 1, 2014, without language restrictions. Studies that compared 25(OH)D levels between IBD patients and controls were selected for inclusion in the meta-analysis. We calculated pooled standardized mean differences (SMDs) and odds ratios (ORs). Results Thirteen case-control studies investigating CD and 25(OH)D levels were included, and eight studies part of above studies also investigated the relationship between UC and 25(OH)D. Both CD patients (SMD: 0.26 nmol/L, 95% confidence interval [CI]: 0.09–0.42 nmol/L) and UC patients (SMD: 0.5 nmol/L, 95% CI: 0.15–0.85 nmol/L) had lower levels of 25(OH)D than controls. In addition, CD patients and UC patients were 1.95 times (OR, 1.95; 95% CI, 1.48–2.57) and 2.02 times (OR, 2.02; 95% CI, 1.13–3.60) more likely to be 25(OH)D deficient than controls. We also included 10 studies investigating the relationship between CD activity and vitamin D. Results showed that patients with active CD (CD Activity Index≥150) were more likely to have low vitamin D levels. In addition, whether low sun exposure and high latitude were related to a high morbidity of CD need to be provided more evidence. Conclusion Our study shows that IBD patients have lower vitamin D levels. For active CD patients, vitamin D levels were low. These findings suggest that vitamin D may play an important role in the development of IBD, although a direct association could not be determined in our study. PMID:26172950

  8. Vitamin D Metabolites Inhibit Hepatitis C Virus and Modulate Cellular Gene Expression

    PubMed Central

    Gutierrez, Julio A.; Jones, Krysten A.; Flores, Roxana; Singhania, Akul; Woelk, Christopher H.; Schooley, Robert T.; Wyles, David L.

    2015-01-01

    Background and Aims Previous studies suggest that low serum 25-hydroxyvitamin D [25(OH) D] levels are associated with reduced responsiveness to interferon and ribavirin therapy. We investigated the impact of vitamin D metabolites on HCV and cellular gene expression in cultured hepatoma cells. Methods HCV Replicon cell lines stably expressing luciferase reporter constructs (genotype 1b and 2a replicon) or JC1-Luc2a were incubated in the presence of vitamin D2, vitamin D3 or 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). Presence of HCV was quantified by a luciferase reporter assay and immunoblot of the Core protein. Synergy of interferon-alpha A/D (IFN-α) and 1,25(OH)2D3 was evaluated using the Chou-Talalay method. Cellular gene expression by microarray analysis using Illumina Bead Chips and real-time quantitative PCR. Results Vitamin D2, D3 and 1,25(OH)2D3 each demonstrated anti-HCV activity at low micro molar concentrations. In vitro conversion from D3 to 25(OH)D3 was shown by LC/MS/MS. Combination indices of 1,25(OH)2D3 and IFN-α demonstrated a synergistic effect (0.23-0.46) and significantly reduced core expression by immunoblot. Differentially expressed genes were identified between Huh7.5.1 cells in the presence and absence of 1,25(OH)2D3 and HCV. Genes involved with classical effects of vitamin D metabolism and excretion were activated, along with genes linked to autophagy such as G-protein coupled receptor 37 (GPR37) and Hypoxia-inducible factor 1-alpha (HIF1a). Additionally, additive effects of 1,25(OH)2D3 and IFN-α were seen on mRNA expression of chemokine motif ligand 20 (CCL20). Conclusions This study shows that vitamin D reduces HCV protein production in cell culture synergistically with IFN-α. Vitamin D also activates gene expression independently and additively with IFN-α and this may explain its ability to aid in the clearance of HCV in vivo. PMID:26594646

  9. Vitamin D2-Enriched Button Mushroom (Agaricus bisporus) Improves Memory in Both Wild Type and APPswe/PS1dE9 Transgenic Mice

    PubMed Central

    Bennett, Louise; Kersaitis, Cindy; Macaulay, Stuart Lance; Münch, Gerald; Niedermayer, Garry; Nigro, Julie; Payne, Matthew; Sheean, Paul; Vallotton, Pascal; Zabaras, Dimitrios; Bird, Michael

    2013-01-01

    Vitamin D deficiency is widespread, affecting over 30% of adult Australians, and increasing up to 80% for at-risk groups including the elderly (age>65). The role for Vitamin D in development of the central nervous system is supported by the association between Vitamin D deficiency and incidence of neurological and psychiatric disorders including Alzheimer’s disease (AD). A reported positive relationship between Vitamin D status and cognitive performance suggests that restoring Vitamin D status might provide a cognitive benefit to those with Vitamin D deficiency. Mushrooms are a rich source of ergosterol, which can be converted to Vitamin D2 by treatment with UV light, presenting a new and convenient dietary source of Vitamin D2. We hypothesised that Vitamin D2-enriched mushrooms (VDM) could prevent the cognitive and pathological abnormalities associated with dementia. Two month old wild type (B6C3) and AD transgenic (APPSwe/PS1dE9) mice were fed a diet either deficient in Vitamin D2 or a diet which was supplemented with VDM, containing 1±0.2 µg/kg (∼54 IU/kg) vitamin D2, for 7 months. Effects of the dietary intervention on memory were assessed pre- and post-feeding. Brain sections were evaluated for amyloid β (Aβ) plaque loads and inflammation biomarkers using immuno-histochemical methods. Plasma vitamin D metabolites, Aβ40, Aβ42, calcium, protein and cholesterol were measured using biochemical assays. Compared with mice on the control diet, VDM-fed wild type and AD transgenic mice displayed improved learning and memory, had significantly reduced amyloid plaque load and glial fibrillary acidic protein, and elevated interleukin-10 in the brain. The results suggest that VDM might provide a dietary source of Vitamin D2 and other bioactives for preventing memory-impairment in dementia. This study supports the need for a randomised clinical trial to determine whether or not VDM consumption can benefit cognitive performance in the wider population. PMID

  10. Effect of 1,25(OH)2D3 on transdifferentiation of rat renal tubular epithelial cells induced by high glucose

    PubMed Central

    Hu, Hongtao; Xu, Shen; Hu, Shuang; Gao, Yue; Shui, Hua

    2016-01-01

    Deficiency in vitamin D and its active metabolite is a characteristic of chronic kidney diseases (CKDs). Previous studies have reported that 1α,25-dihydroxyvitamin D3 [1,25(OH)2D3], the active form of vitamin D, can attenuate renal interstitial fibrosis. The present study aimed to explore the effect of 1,25(OH)2D3 on the transdifferentiation of NRK-52E rat renal tubular epithelial cells (RTECs) induced by high glucose, as well as the expression of vitamin D receptor (VDR) and production of angiotensin (Ang) II. Western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) analyses were performed to detect the protein and mRNA expression of α-smooth muscle actin (α-SMA), E-cadherin and VDR. Furthermore, the production of Ang II was analyzed by enzyme-linked immunosorbent assay (ELISA). Treatment with high glucose decreased E-cadherin and VDR, while increasing α-SMA and Ang II, and of note, these changes were attenuated by 1,25(OH)2D3 in a dose-dependent manner. In conclusion, the present study revealed that 1,25(OH)2D3 inhibits high glucose-induced transdifferentiation of rat RTECs in a dose-dependent manner, which may be associated with the downregulation of Ang II and upregulation of VDR. PMID:28101343

  11. Use of surface plasmon resonance in the binding study of vitamin D, metabolites and analogues with vitamin D binding protein.

    PubMed

    Canoa, Pilar; Rivadulla, Marcos L; Popplewell, Jonathan; van Oosten, René; Gómez, Generosa; Fall, Yagamare

    2017-04-01

    Vitamin D3 and its metabolites are lipophilic molecules with low aqueous solubility and must be transported bound to plasma carrier proteins, primarily to vitamin D binding protein (DBP). The biological functions of vitamin D3 metabolites are intimately dependent on the protein, hence the importance of determining their affinity for DBP. In this study, we developed a novel procedure for measuring the kinetic and equilibrium constants of human-DBP with vitamin D3 and three metabolites: 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], 25-hydroxyvitamin D3 (25OHD3) and 24,25-dihydroxyvitamin D3 [24,25(OH)2D3] by surface plasmon resonance (SPR). At the same time, five different analogues, synthetized in our laboratory, were evaluated in order to compare the affinity values with the metabolites. Real-time SPR measurements showed that 25OHD3 and 24,25(OH)2D3 had higher affinity (0.3 μM) than 1,25(OH)2D3 (5 μM), with the higher affinity of 25OHD3 and 24,25(OH)2D3 due to dissociation constants 1 order of magnitude slower. In the case of the analogues, the affinity values were lower, with 1-hydroxy-25-nitro-vitamin D3 (NO2-446), structurally closer to 1,25(OH)2D3, showing the highest value with a K D of 50 μM. (24R)-1,25-dihydroxyvitamin-24-buthyl-28-norvitamin D2 (Bu-471) and (24R)-1,25-dihydroxyvitamin-24-phenyl-28-norvitamin D2 (Ph-491), structurally similar, had affinities of 180 and 170 μM, respectively. (22R,23E)-1-hydroxy-22-ethenyl-25-methoxy-23-dehydrovitamin D3 (MeO-455) and 1-hydroxy-20(R)-[5(S)-(2,2-dimethyltetrahydropyran-5-yl)]-22,23-dinor vitamin D3 (Oxan-429) had affinities of 310 and 100 μM, respectively. The binding of the metabolites and analogues was reversible allowing the rapid capture of data for replicates. The kinetic and equilibrium data for both the metabolites and the analogues fitted to the Langmuir model describing a 1:1 interaction. Graphical Abstract Label-free, real time binding study between vitamin D binding protein immmobilized on the

  12. [Chronic kidney insufficiency and respiratory muscle function. Changes induced by treatment with 1,25(OH)2D3].

    PubMed

    Gómez-Fernández, P; Sánchez Agudo, L; Calatrava, J M

    1990-02-17

    A myopathy basically involving proximal respiratory muscles can develop in uremia. To evaluate respiratory muscle force in uremia, maximal inspiratory pressure (MIP) was measured in 27 patients with renal failure. MIP was very limited in patients with a creatinine clearance (Crc) lower than 10/ml/min 1.73 m2 not treated with hemodialysis (HD) and in patients on HD who were not treated with 1.25 (OH)2D3 (45 +/- 9 and 43 +/- 5 cm H2O, respectively), moderately reduced in patients on HD treated with 1.25 (OH)2D3 (58 +/- 5 cmH2O) and normal in patients with Crc higher than 10 ml/min 1.73 m2 (86 +/- 6 cmH2O). The treatment with 1.25 (OH)2D3 during 3 months promoted a significant increase in MIP and serum calcium level and a reduction in parathyroid hormone in patients with Crc lower than 10 ml/min. It was concluded that, in uremia, a respiratory muscle weakness partially reversible with vitamin D therapy may be found.

  13. Effects of UV-C treatment and cold storage on ergosterol and vitamin D2 contents in different parts of white and brown mushroom (Agaricus bisporus).

    PubMed

    Guan, Wenqiang; Zhang, Jie; Yan, Ruixiang; Shao, Suqin; Zhou, Ting; Lei, Jing; Wang, Zhidong

    2016-11-01

    Effects of ultraviolet-C (UV-C) treatment (0.5, 1.0 and 2.0kJ/m(2)) and cold storage on ergosterol and vitamin D2 content in different parts of white and brown button mushrooms (Agaricus bisporus) were investigated. UV-C treatment did not significantly affect ergosterol content in the caps and stems of the two mushrooms, but ergosterol content increased significantly during 14days cold storage. Vitamin D2 content in the caps and stems of two mushrooms significantly increased as UV-C dose increased, and 2.0kJ/m(2) UV-C showed the best result. During cold storage, vitamin D2 content in the caps of the two mushrooms decreased from day 1 to day 7, and then kept stable until day 14, but vitamin D2 content in the stems of brown mushrooms kept increasing for the whole 14days period. UV-C could increase vitamin D2 contents in both caps and stems of white and brown mushrooms without significantly affecting ergosterol content.

  14. 1alpha,25(OH)2D3 is an autocrine regulator of extracellular matrix turnover and growth factor release via ERp60 activated matrix vesicle metalloproteinases.

    PubMed

    Boyan, Barbara D; Wong, Kevin L; Fang, Mimi; Schwartz, Zvi

    2007-03-01

    Growth plate chondrocytes produce proteoglycan-rich type II collagen extracellular matrix (ECM). During cell maturation and hypertrophy, ECM is reorganized via a process regulated by 1alpha,25(OH)(2)D(3) and involving matrix metalloproteinases (MMPs), including MMP-3 and MMP-2. 1alpha,25(OH)(2)D(3) regulates MMP incorporation into matrix vesicles (MVs), where they are stored until released. Like plasma membranes (PM), MVs contain the 1alpha,25(OH)(2)D(3)-binding protein ERp60, phospholipase A(2) (PLA(2)), and caveolin-1, but appear to lack nuclear Vitamin D receptors (VDRs). Chondrocytes produce 1alpha,25(OH)(2)D(3) (10(-8)M), which binds ERp60, activating PLA(2), and resulting lysophospholipids lead to MV membrane disorganization, releasing active MMPs. MV MMP-3 activates TGF-beta1 stored in the ECM as large latent TGF-beta1 complexes, consisting of latent TGF-beta1 binding protein, latency associated peptide, and latent TGF-beta1. Others have shown that MMP-2 specifically activates TGF-beta2. TGF-beta1 regulates 1alpha,25(OH)(2)D(3)-production, providing a mechanism for local control of growth factor activation. 1alpha,25(OH)(2)D(3) activates PKCalpha in the PM via ERp60-signaling through PLA(2), lysophospholipid production, and PLCbeta. It also regulates distribution of phospholipids and PKC isoforms between MVs and PMs, enriching the MVs in PKCzeta. Direct activation of MMP-3 in MVs requires ERp60. However, when MVs are treated with 1alpha,25(OH)(2)D(3), PKCzeta activity is decreased and PKCalpha is unaffected, suggesting a more complex feedback mechanism, potentially involving MV lipid signaling.

  15. 1α,25(OH)2D3-dependent modulation of Akt in proliferating and differentiating C2C12 skeletal muscle cells.

    PubMed

    Buitrago, Claudia G; Arango, Nadia S; Boland, Ricardo L

    2012-04-01

    We previously reported that 1α,25-dihydroxy-vitamin D(3) [1α,25(OH)(2)D(3)] induces non-transcriptional rapid responses through activation of Src and MAPKs in the skeletal muscle cell line C2C12. In the present study we investigated the modulation of Akt by the secosteroid hormone in C2C12 cells at proliferative stage (myoblasts) and at early differentiation stage. In proliferating cells, 1α,25(OH)(2)D(3) activates Akt by phosphorylation in Ser473 in a time-dependent manner (5-60 min). When these cells were pretreated with methyl-beta-cyclodextrin to disrupt caveolae microdomains, hormone-induced activation of Akt was suppressed. Similar results were obtained by siRNA silencing of caveolin-1 expression, further indicating that hormone effects on cell membrane caveolae are required for downstream signaling. PI3K and p38 MAPK, but not ERK1/2, participate in 1α,25(OH)(2)D(3) activation of Akt in myoblasts. The involvement of p38 MAPK in Akt phosphorylation by the hormone probably occurs through MAPK-activated protein kinase 2 (MK2), which is activated by the steroid. In addition, the participation of Src in Akt phosphorylation by 1α,25(OH)(2)D(3) was demonstrated using the inhibitor PP2 and antisense oligodeoxynucleotides that suppress Src expression. We also observed that PI3K participates in hormone-induced proliferation. During the early phase of C2C12 cell differentiation 1α,25(OH)(2)D(3) also increases Akt phosphorylation and activates Src. Of relevance, Src and PI3K are involved in Akt activation and in MHC and myogenin increased expression by 1α,25(OH)(2)D(3). Altogether, these data suggest that 1α,25(OH)(2)D(3) upregulates Akt through Src, PI(3)K, and p38 MAPK to stimulate myogenesis in C2C12 cells.

  16. Analysis of Vitamin D2 and Vitamin D3 in Fortified Milk Powders and Infant and Nutritional Formulas by Liquid Chromatography-Tandem Mass Spectrometry: Single-Laboratory Validation, First Action 2016.05.

    PubMed

    Gill, Brendon D; Abernethy, Grant A; Green, Rebecca J; Indyk, Harvey E

    2016-09-01

    A method for the determination of vitamin D2 and vitamin D3 in fortified milk powders and infant and adult nutritional formulas is described. Samples are saponified at high temperature and lipid-soluble components are extracted into isooctane. A portion of the isooctane layer is transferred and washed, and an aliquot of 4-phenyl-1,2,4-triazoline-3,5-dione is added to derivatize the vitamin D to form a high-molecular-mass, easily ionizable adduct. The vitamin D adduct is then re-extracted into a small volume of acetonitrile and analyzed by RPLC. Detection is by tandem MS, using multiple reaction monitoring. Stable isotope-labeled vitamin D2 and vitamin D3 internal standards are used for quantitation to correct for losses in extraction and any variation in derivatization and ionization efficiencies. A single-laboratory validation of the method using AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) kit samples was performed and compared with parameters defined according to the vitamin D Standard Method Performance Requirements (SMPR(®)). Linearity was demonstrated over the range specified in the SMPR, with the LOD being estimated at below that required. Method spike recovery (vitamin D2, 97.0-99.2%; and vitamin D3, 96.0-101.0%) and RSDr (vitamin D3, 1.5-5.2%) were evaluated and compared favorably with limits in the vitamin D SMPR. Acceptable bias for vitamin D3 was demonstrated against both the certified value for National Institute of Standards and Technology 1849a Standard Reference material (P(α = 0.05) = 0.25) and AOAC INTERNATIONAL reference method 2002.05 (P(α = 0.05) = 0.09). The method was demonstrated to meet the requirements of the vitamin D SMPR as defined by SPIFAN, and was recently approved for Official First Action status by the AOAC Expert Review Panel on SPIFAN Nutrient Methods.

  17. Antiproliferative Activity of Double Point Modified Analogs of 1,25-Dihydroxyvitamin D2 Against Human Malignant Melanoma Cell Lines

    PubMed Central

    Piotrowska, Anna; Wierzbicka, Justyna; Nadkarni, Sharmin; Brown, Geoffrey; Kutner, Andrzej; Żmijewski, Michał A.

    2016-01-01

    Vitamin D is a lipid soluble steroid hormone with pleiotropic biological properties, including regulation of cell proliferation, differentiation and apoptosis. As to these desirable anticancer actions, 1,25-dihydroxyvitamins D and analogs have been reported to inhibit the proliferation and to induce differentiation of a wide variety of cancer cell types, including human malignant melanoma. However, there is a need for novel and more efficacious vitamin D analogs, and how best to design such is still an open issue. A series of double point modified (DPM) analogs of 1,25-dihydroxyvitamin D2 (1,25(OH)2D2) induced differentiation of the vitamin D receptor (VDR) positive A375 and VDR negative SK-MEL 188b human malignant melanoma cell lines. Surprisingly, the dose of 1,25(OH)2D2 required to inhibit the proliferation of the A375 melanoma cell line by was several fold lower than that required in the case of 1,25(OH)2D3. To evaluate the impact of the modification in the side chain (additional 22-hydroxyl) and in the A-ring (5,6-trans modification), the regular side-chain of vitamin D2 or D3 was retained in the structure of our analogs. As expected, 5,6-trans modification was advantageous to enhancing the anti-proliferative activity of analogs, but not as a single point modification (SPM). Very unexpectedly, the additional 22-hydroxyl in the side-chain reduced significantly the anti-proliferative activity of both the natural and 5,6-trans series analogs. Finally, an induction of pigmentation in melanoma SK-MEL 188b cells was observed to sensitized cells to the effect of vitamin D analogs. PMID:26760999

  18. Double bond in the side chain of 1alpha,25-dihydroxy-22-ene-vitamin D(3) is reduced during its metabolism: studies in chronic myeloid leukemia (RWLeu-4) cells and rat kidney.

    PubMed

    Sunita Rao, D; Balkundi, D; Uskokovic, M R; Tserng, K; Clark, J W; Horst, R L; Satyanarayana Reddy, G

    2001-08-01

    1alpha,25-Dihydroxyvitamin D(3) [1alpha,25(OH)(2)D(3)] is mainly metabolized via the C-24 oxidation pathway and undergoes several side chain modifications which include C-24 hydroxylation, C-24 ketonization, C-23 hydroxylation and side chain cleavage between C-23 and C-24 to form the final product, calcitroic acid. In a recent study we reported that 1alpha,25-dihydroxyvitamin D(2) [1alpha,25(OH)(2)D(2)] like 1alpha,25(OH)(2)D(3), is also converted into the same final product, calcitroic acid. This finding indicated that 1alpha,25(OH)(2)D(2) also undergoes side chain cleavage between C-23 and C-24. As the side chain of 1alpha,25(OH)(2)D(2) when compared to the side chain of 1alpha,25(OH)(2)D(3), has a double bond between C-22 and C-23 and an extra methyl group at C-24 position, it opens the possibility for both (a) double bond reduction and (b) demethylation to occur during the metabolism of 1alpha,25(OH)(2)D(2). We undertook the present study to establish firmly the possibility of double bond reduction in the metabolism of vitamin D(2) related compounds. We compared the metabolism of 1alpha,25-dihydroxy-22-ene-vitamin D(3) [1alpha,25(OH)(2)-22-ene-D(3)], a synthetic vitamin D analog whose side chain differs from that of 1alpha,25(OH)(2)D(3) only through a single modification namely the presence of a double bond between C-22 and C-23. Metabolism studies were performed in the chronic myeloid leukemic cell line (RWLeu-4) and in the isolated perfused rat kidney. Our results indicate that both 1alpha,25(OH)(2)-22-ene-D(3) and 1alpha,25(OH)(2)D(3) are converted into common metabolites namely, 1alpha,24(R),25-trihydroxyvitamin D(3) [1alpha,24(R),25(OH)(3)D(3)], 1alpha,25-dihydroxy-24-oxovitamin D(3) [1alpha,25(OH)(2)-24-oxo-D(3)], 1alpha,23(S),25-trihydroxy-24-oxovitamin D(3) and 1alpha,23-dihydroxy-24,25,26,27-tetranorvitamin D(3). This finding indicates that the double bond in the side chain of 1alpha,25(OH)(2)-22-ene-D(3) is reduced during its metabolism. Along with

  19. Super pharmacological levels of calcitriol (1,25-(OH)2D3) inhibits mineral deposition and decreases cell proliferation in a strain dependent manner in chicken mesenchymal stem cells undergoing osteogenic differentiation in vitro.

    PubMed

    Pande, Vivek V; Chousalkar, Kapil C; Bhanugopan, Marie S; Quinn, Jane C

    2015-11-01

    The biologically active form of vitamin D₃, calcitriol (1,25-(OH)₂D₃), plays a key role in mineral homeostasis and bone formation and dietary vitamin D₃deficiency is a major cause of bone disorders in poultry. Supplementary dietary cholecalciferol (25-hydroxyvitamin D, 25-OH), the precursor of calcitriol, is commonly employed to combat this problem; however, dosage must be carefully determined as excess dietary vitamin D can cause toxicity resulting in a decrease in bone calcification, hypercalcinemia and renal failure. Despite much research on the therapeutic administration of dietary vitamin D in humans, the relative sensitivity of avian species to exogenous vitamin D has not been well defined. In order to determine the effects of exogenous 1,25-(OH)₂D₃during avian osteogenesis, chicken bone marrow-derived mesenchymal stem cells (BM-MSCs) were exposed to varying doses of 1,25-(OH)₂D₃during in vitro osteogenic differentiation and examined for markers of early proliferation and osteogenic induction. Similar to humans and other mammals, poultry BM-MSCs were found to be highly sensitive to exogenous 1,25-(OH)₂D₃with super pharmacological levels exerting significant inhibition of mineralization and loss of cell proliferation in vitro. Strain related differences were apparent, with BM-MCSs derived from layers strains showing a higher level of sensitivity to 1,25-(OH)₂D₃than those from broilers. These data suggest that understanding species and strain specific sensitivities to 1,25-(OH)₂D₃is important for optimizing bone health in the poultry industry and that use of avian BM-MSCs are a useful tool for examining underlying effects of genetic variation in poultry.

  20. Vitamin D and inflammation

    PubMed Central

    Cannell, John J; Grant, William B; Holick, Michael F

    2014-01-01

    Several studies found an inverse relationship between 25-hydroxyvitamin D [25(OH)D] and markers of inflammation. A controversy exists as to whether vitamin D lowers inflammation or whether inflammation lowers 25(OH)D concentrations. Certainly 25(OH)D concentrations fall after major surgery. However, is this due to inflammation lowering 25(OH)D or is 25(OH)D being metabolically cleared by the body to quell inflammation. We searched the literature and found 39 randomized controlled trials (RCT) of vitamin D and markers of inflammation. Seventeen found significantly reduced inflammatory markers, 19 did not, one was mixed and one showed adverse results. With few exceptions, studies in normal subjects, obesity, type 2 diabetics, and stable cardiovascular disease did not find significant beneficial effects. However, we found that 6 out of 7 RCTS of vitamin D3 in highly inflammatory conditions (acute infantile congestive heart failure, multiple sclerosis, inflammatory bowel disease, cystic fibrosis, SLE, active TB and evolving myocardial infarction) found significant reductions. We found baseline and final 25(OH)D predicted RCTs with significant reduction in inflammatory markers. Vitamin D tends to modestly lower markers of inflammation in highly inflammatory conditions, when baseline 25(OH)D levels were low and when achieved 25(OH)D levels were higher. Future inquiries should: recruit subjects with low baseline 25(OH)D levels, subjects with elevated markers of inflammation, subjects with inflammatory conditions, achieve adequate final 25(OH)D levels, and use physiological doses of vitamin D. We attempted to identify all extant randomized controlled trials (RCTs) of vitamin D that used inflammatory markers as primary or secondary endpoints. PMID:26413186

  1. Quantification of 1α,25 Dihydroxy Vitamin D by Immunoextraction and Liquid Chromatography-Tandem Mass Spectrometry

    PubMed Central

    Strathmann, Frederick G.; Laha, Thomas J.; Hoofnagle, Andrew N.

    2012-01-01

    Background 1α,25-dihydroxy vitamin D [1,25(OH)2D] is the active metabolite of vitamin D. Antibody-based detection methods lack specificity, but when combined with isotope dilution-UPLC-tandem mass spectrometry, immunoextraction provides an attractive method for 1,25(OH)2D. We developed a method for simultaneous quantification of 1,25(OH)2D2 and 1,25(OH)2D3 with a 4.6 min instrument cycle time. Results are available 36 h after sample preparation begins. Methods Sample preparation consisted of protein precipitation, immunoextraction with solid-phase anti-1,25(OH)2D antibody, and derivatization with 4-phenyl-1,2,4-triazoline-3,5-dione. Analytes were resolved using reversed-phase UPLC and quantified using positive ion electrospray ionization-tandem mass spectrometry. Hexadeuterated 1,25(OH)2D3 and 1,25(OH)2D2 were used as internal standards. Method comparisons were performed against the DiaSorin RIA and an LC-MS/MS method available at a reference laboratory. Results 1,25(OH)2D3 intra-assay and inter-assay imprecision was 5.6% and 8.0% (120 pmol/L) and 8.7% and 13% (48 pmol/L). Limits of detection and quantification were 1.5 pmol/L and 3.0 pmol/L, respectively. 1,25(OH)2D2 intra-assay and inter-assay imprecision was 8.7% and 11% (186 pmol/L) and 11% and 13% (58 pmol/L). Limits of detection and quantification were 1.5 pmol/L. Comparison with RIA had a proportional bias of 0.75, constant bias of −4.1 and Pearson correlation (r2) of 0.31. Comparison with a reference LC-MS/MS assay had a porportional bias of 0.89, constant bias of 3.7 and Pearson correlation (r2) of 0.88. Conclusion Protein precipitation with antibody-based extraction is effective for sample preparation prior to LC-MS/MS analysis of derivatized 1,25(OH)2D. This method appears to have improved specificity over a clinically-used RIA with low imprecision and limits of detection. PMID:21768219

  2. Simultaneous determination of vitamins D2 and D3 by electrospray ionization LC/MS/MS in infant formula and adult nutritionals: First Action 2012.11.

    PubMed

    Gilliland, Donald L; Black, Charles K; Denison, James E; Seipelt, Charles T; Baugh, Steve

    2013-01-01

    A method was developed for the analysis of vitamins D2 and D3 in a variety of nutritional products. To extract vitamins D2 and D3 from products containing substantial amounts of fat, a saponification with alcoholic potassium hydroxide is required to release the vitamin D. Trideuterium-labeled vitamin D is added to the sample prior to saponification, and quantitation is achieved using linear regression of the ratio of peak response for 2H3-D and vitamin D. Acceptable linearity was achieved between 0.6 and 27 microg/100 g with a correlation requirement of >0.999. The method detection limit of 0.02 microg/100 g was verified by spiking placebo products carried through the saponification and extraction steps of the method. At the quantitation limit (0.12 microg/100 g), the signal was easily distinguished from the background. Vitamin D3 spike recoveries ranged from 107 to 119% at the low level and 104 to 116% at the high-level spike. Vitamin D2 recoveries were 105 to 116% and 91 to 110% for the low- and high-level spikes, respectively. SRM 1849a has a certified concentration of 11.1 +/- 1.7 microg/100 g; using this standard reference material, the range of 9.4 to 12.8 microg/100 g was met on each of the 6 days. Method repeatability, determined in 12 vitamin D3 product matrixes over 6 days, ranged from 3.9 to 48%. The adult nutrition-milk protein sample was the most notable; it failed within-day, as well as day-to-day, precision requirements. There was no attempt to optimize the sample preparation to accommodate any problem matrix.

  3. Cell cycle arrest and apoptosis induced by 1α,25(OH)2D3 and TX 527 in Kaposi sarcoma is VDR dependent.

    PubMed

    González-Pardo, Verónica; Suares, Alejandra; Verstuyf, Annemieke; De Clercq, Pierre; Boland, Ricardo; de Boland, Ana Russo

    2014-10-01

    We have previously shown that 1α,25(OH)2-Vitamin D3 [1α,25(OH)2D3] and its less calcemic analog TX 527 inhibit the proliferation of endothelial cells transformed by the viral G protein-coupled receptor associated to Kaposi sarcoma (vGPCR) and this could be partially explained by the inhibition of the NF-κB pathway. In this work, we further explored the mechanism of action of both vitamin D compounds in Kaposi sarcoma. We investigated whether the cell cycle arrest and subsequent apoptosis of endothelial cells (SVEC) and SVEC transformed by vGPCR (SVEC-vGPCR) elicited by 1α,25(OH)2D3 and TX 527 were mediated by the vitamin D receptor (VDR). Cell cycle analysis of SVEC and SVEC-vGPCR treated with 1α,25(OH)2D3 (10nM, 48h) revealed that 1α,25(OH)2D3 increased the percentage of cells in the G0/G1 phase and diminished the percentage of cells in the S phase of the cell cycle. Moreover, the number of cells in the S phase was higher in SVEC-vGPCR than in SVEC due to vGPCR expression. TX 527 exerted similar effects on growth arrest in SVEC-vGPCR cells. The cell cycle changes were suppressed when the expression of the VDR was blocked by a stable transfection of shRNA against VDR. Annexin V-PI staining demonstrated apoptosis in both SVEC and SVEC-vGPCR after 1α,25(OH)2D3 and TX 527 treatment (10nM, 24h). Cleavage of caspase-3 detected by Western blot analysis was increased to a greater extent in SVEC than in SVEC-vGPCR cells, and this effect was also blocked in VDR knockdown cells. Altogether, these results suggest that 1α,25(OH)2D3 and TX 527 inhibit the proliferation of SVEC and SVEC-vGPCR and induce apoptosis by a mechanism that involves the VDR.

  4. Serum 25(OH)D Is a 2-Year Predictor of All-Cause Mortality, Cardiac Death and Sudden Cardiac Death in Chest Pain Patients from Northern Argentina

    PubMed Central

    Naesgaard, Patrycja A.; León De La Fuente, Ricardo A.; Nilsen, Stein Tore; Woie, Leik; Aarsland, Torbjoern; Brede, Cato; Staines, Harry; Nilsen, Dennis W. T.

    2012-01-01

    Background Several studies have shown an association between vitamin D deficiency and cardiovascular risk. Vitamin D status is assessed by determination of 25-hydroxyvitamin D [25(OH)D] in serum. Methods We assessed the prognostic utility of 25(OH)D in 982 chest-pain patients with suspected acute coronary syndrome (ACS) from Salta, Northern Argentina. 2-year follow-up data including all-cause mortality, cardiac death and sudden cardiac death were analyzed in quartiles of 25(OH)D, applying univariate and multivariate analysis. Results There were statistically significant changes in seasonal 25(OH)D levels. At follow-up, 119 patients had died. The mean 25(OH)D levels were significantly lower among patients dying than in long-term survivors, both in the total population and in patients with a troponin T (TnT) release (n = 388). When comparing 25(OH)D in the highest quartile to the lowest quartile in a multivariable Cox regression model for all-cause mortality, the hazard ratio (HR) for cardiac death and sudden cardiac death in the total population was 0.37 (95% CI, 0.19–0.73), p = 0.004, 0.23 (95% CI, 0.08–0.67), p = 0.007, and 0.32 (95% CI, 0.11–0.94), p = 0.038, respectively. In patients with TnT release, the respective HR was 0.24 (95% CI, 0.10–0.54), p = 0.001, 0.18 (95% CI, 0.05–0.60), p = 0.006 and 0.25 (95% CI, 0.07–0.89), p = 0.033. 25(OH)D had no prognostic value in patients with no TnT release. Conclusion Vitamin D was shown to be a useful biomarker for prediction of mortality when obtained at admission in chest pain patients with suspected ACS. Trial registration ClinicalTrials.gov NCT01377402 PMID:22970121

  5. Simultaneous determination of vitamins D2 and D3 by LC-MS/MS in infant formula and adult nutritionals: First Action 2011.13.

    PubMed

    Gilliland, Donald L; Black, Charles K; Denison, James E; Seipelt, Charles T

    2012-01-01

    During the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting" held on June 29, 2011, an Expert Review Panel (ERP) on behalf of AOAC INTERNATIONAL adopted the method "Simultaneous Determination of Vitamins D2 and D3 by LC-MS/MS in Infant Formula and Adult Nutritionals" as an AOAC Official First Action method. Vitamins D2 and D3 are extracted from the sample using pentane-ether; the extract is collected and dried under nitrogen. Vitamin D is separated from interfering compounds using UPLC, and quantitated using tandem mass spectrometry (MS/MS). Preliminary data showed the intermediate precision ranged from 3.34-8.05% and an accuracy range of 98.5-111% over the samples tested for vitamin D3. For vitamin D2, the intermediate precision ranged from 2.37-5.45% and accuracy ranged from 96.4-104% over the four matrixes evaluated. The analytical range for the method is bounded by the concentrations of the working standards, 21-270 ng/mL, and is equivalent to 0.168-2.16 mcg/100 g in ready-to-feed product. The practical method quantitation limit is 0.168 mcg/100 g product with method detection limit of 60 ng/100 g product. The ERP reviewed the data and determined that the performance characteristics of the method met the standard method performance requirements, and therefore the method was granted First Action status.

  6. Extract-filter-shoot liquid chromatography with mass spectrometry for the analysis of vitamin D2 in a powdered supplement capsule and standard reference material 3280.

    PubMed

    Byrdwell, William Craig

    2014-08-01

    An "extract-filter-shoot" method for the analysis of vitamin D2, ergocalciferol, in a dry powdered dietary supplement capsule containing rice flour excipient and in a National Institute of Standards and Technology standard reference material 3280 is reported. Quantification of vitamin D2 was done by atmospheric pressure chemical ionization mass spectrometry using selected ion monitoring, two transitions of selected reaction monitoring, and extracted ion chromatograms from full scans. UV detection was used for the quantification of Vitamin D2 in the dry powder capsule, whereas interfering species rendered UV detection unreliable for standard reference material 3280. Average values for standard reference material 3280 ranged from 8.27 ± 0.58 to 8.33 ± 0.57 μg/g using internal standard calibration and response factor approaches, compared to the previous National Institute of Standards and Technology internal value for vitamin D2 of 8.78 ± 0.11 μg/g, and the recently updated reference value of 8.6 ± 2.6 μg/g. The powdered supplement capsule was found to contain 28.19 ± 0.35 to 28.67 ± 0.90 μg/capsule for a capsule labeled to contain 25.00 μg. The triacylglycerol composition of the rice flour excipient in the powdered supplement capsule determined by atmospheric pressure chemical ionization mass spectrometry is also reported.

  7. Vitamin D status of dairy cattle: Outcomes of current practices in the dairy industry.

    PubMed

    Nelson, Corwin D; Lippolis, John D; Reinhardt, Timothy A; Sacco, Randy E; Powell, Jessi L; Drewnoski, Mary E; O'Neil, Matthew; Beitz, Donald C; Weiss, William P

    2016-12-01

    The need for vitamin D supplementation of dairy cattle has been known for the better part of the last century and is well appreciated by dairy producers and nutritionists. Whether current recommendations and practices for supplemental vitamin D are meeting the needs of dairy cattle, however, is not well known. The vitamin D status of animals is reliably indicated by the concentration of the 25-hydroxyvitamin D [25(OH)D] metabolite in serum or plasma, with a concentration of 30ng/mL proposed as a lower threshold for sufficiency. The objective of this study was to determine the typical serum 25(OH)D concentrations of dairy cattle across various dairy operations. The serum 25(OH)D concentration of 702 samples collected from cows across various stages of lactation, housing systems, and locations in the United States was 68±22ng/mL (mean ± standard deviation), with the majority of samples between 40 and 100ng/mL. Most of the 12 herds surveyed supplemented cows with 30,000 to 50,000 IU of vitamin D3/d, and average serum 25(OH)D of cows at 100 to 300 DIM in each of those herds was near or above 70ng/mL regardless of season or housing. In contrast, average serum 25(OH)D of a herd supplementing with 20,000 IU/d was 42±15ng/mL, with 22% below 30ng/mL. Cows in early lactation (0 to 30d in milk) also had lower serum 25(OH)D than did mid- to late-lactation cows (57±17 vs. 71±20ng/mL, respectively). Serum 25(OH)D of yearling heifers receiving 11,000 to 12,000 IU of vitamin D3/d was near that of cows at 76±15ng/mL. Serum 25(OH)D concentrations of calves, on the other hand, was 15±11ng/mL at birth and remained near or below 15ng/mL through 1mo of age if they were fed pasteurized waste milk with little to no summer sun exposure. In contrast, serum 25(OH)D of calves fed milk replacer containing 6,600 and 11,000 IU of vitamin D2/kg of dry matter were 59±8 and 98±33ng/mL, respectively, at 1mo of age. Experimental data from calves similarly indicated that serum 25(OH

  8. Quantitation of the main metabolites of vitamin D in a single serum sample. I. Extraction, separation and purification of metabolites.

    PubMed

    Aksnes, L

    1980-06-10

    A method for extraction, separation and purification of the main serum metabolites of vitamin D from a single serum sample is described. The method involved extraction of serum by diethylether and separation and purification of vitamin D, 25-OHD and the dihydroxymetabolites 24,25-(OH)2D, 25,26-(OH),2D and 1,25-(OH)2D by elution in three steps from a short open silicic acid column. The eluted vitamin D metabolites were further separated and purified by high pressure liquid chromatography (HPLC). The HPLC systems described separated the D2 and D3 forms of vitamin D, 25-OHD, 1,25-(OH)2D, and probably also 24,25-(OH)2D and 25,26-(OH)2D. The metabolites were purified by the methods described for further quantitation by UV-absorption or competitive protein binding assays, and were found to be homogenous on re-chromatography with different HPLC systems. Good recoveries were obtained for all the metabolites.

  9. Plant Oils as Potential Sources of Vitamin D

    PubMed Central

    Baur, Anja C.; Brandsch, Corinna; König, Bettina; Hirche, Frank; Stangl, Gabriele I.

    2016-01-01

    To combat vitamin D insufficiency in a population, reliable diet sources of vitamin D are required. The recommendations to consume more oily fish and the use of UVB-treated yeast are already applied strategies to address vitamin D insufficiency. This study aimed to elucidate the suitability of plant oils as an alternative vitamin D source. Therefore, plant oils that are commonly used in human nutrition were first analyzed for their content of vitamin D precursors and metabolites. Second, selected oils were exposed to a short-term UVB irradiation to stimulate the synthesis of vitamin D. Finally, to elucidate the efficacy of plant-derived vitamin D to improve the vitamin D status, we fed UVB-exposed wheat germ oil (WGO) for 4 weeks to mice and compared them with mice that received non-exposed or vitamin D3 supplemented WGO. Sterol analysis revealed that the selected plant oils contained high amounts of not only ergosterol but also 7-dehydrocholesterol (7-DHC), with the highest concentrations found in WGO. Exposure to UVB irradiation resulted in a partial conversion of ergosterol and 7-DHC to vitamin D2 and D3 in these oils. Mice fed the UVB-exposed WGO were able to improve their vitamin D status as shown by the rise in the plasma concentration of 25-hydroxyvitamin D [25(OH)D] and the liver content of vitamin D compared with mice fed the non-exposed oil. However, the plasma concentration of 25(OH)D of mice fed the UVB-treated oil did not reach the values observed in the group fed the D3 supplemented oil. It was striking that the intake of the UVB-exposed oil resulted in distinct accumulation of vitamin D2 in the livers of these mice. In conclusion, plant oils, in particular WGO, contain considerable amounts of vitamin D precursors which can be converted to vitamin D via UVB exposure. However, the UVB-exposed WGO was less effective to improve the 25(OH)D plasma concentration than a supplementation with vitamin D3. PMID:27570765

  10. Correlation between Bethatrophin and 25(OH)D Concentrations in a Group of Subjects With Normal and Impaired Glucose Metabolism.

    PubMed

    Turkon, H; Yalcın, H; Toprak, B; Demirpençe, M; Yaşar, H Y; Colak, A

    2016-02-24

    Aim: Inducing beta cell replication is a potential therapeutic approach for the treatment of diabetes mellitus. Recently betatrophin was suggested as a novel stimulator of beta cell proliferation in mice but its role in humans remains to be established. We aimed to investigate betatrophin concentration and its association with metabolic parameters in a group of individuals with normal glucose tolerance, pre-diabetes and diabetes mellitus who had not been previously treated. Methods: A total of 72 subjects were recruited for this cross sectional study: 23 subjects with normal glucose tolerance (NGT), 22 subjects with prediabetes, and 27 subjects with diabetes mellitus (DM). Circulating betatrophin concentration, 75 g oral glucose tolerance test, fasting insulin, glycosylated hemoglobin, 25hydroxy vitamin D and HOMA IR were measured. Results: The difference in betatrophin values did not reach statistical significance between the 3 groups [NGT:206 (176-297)pg/mL, Prediabetes:232 (181-254)pg/mL, DM:245 (205-526)pg/mL, p=0.078]. Betatrophin was negatively significantly correlated with BMI and positively significantly correlated with 25(OH)vitD (p=0.043 and p=0.001 respectively). Multivariate linear regression showed that 25(OH) vitD (β=0.440 p=0.001) and fasting glucose (β=0.003 p=0.038) were variables associated with betatrophin concentration (R2=0.251). Conclusions: In a group of subjects ranging from those with normal glucose tolerance to newly diagnosed diabetes, we found that 25(OH)D and fasting glucose were factors associated with serum betatrophin concentration.

  11. Simultaneous quantitative analysis of eight vitamin D analogues in milk using liquid chromatography-tandem mass spectrometry.

    PubMed

    Gomes, Fabio P; Shaw, P Nicholas; Whitfield, Karen; Hewavitharana, Amitha K

    2015-09-03

    Milk is an important source of nutrients for various risk populations, including infants. The accurate measurement of vitamin D in milk is necessary to provide adequate supplementation advice for risk groups and to monitor regulatory compliance. Currently used liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods are capable of measuring only four analogues of vitamin D in unfortified milk. We report here an accurate quantitative analytical method for eight analogues of vitamin D: Vitamin D2 and D3 (D2 and D3), 25-hydroxy D2 and D3, 24,25-dihydroxy D2 and D3, and 1,25-dihydroxyD2 and D3. In this study, we compared saponification and protein precipitation for the extraction of vitamin D from milk and found the latter to be more effective. We also optimised the pre-column derivatisation using 4-phenyl-l,2,4-triazoline-3,5-dione (PTAD), to achieve the highest sensitivity and accuracy for all major vitamin D forms in milk. Chromatography was optimised to reduce matrix effects such as ion-suppression, and the matrix effects were eliminated using co-eluting stable isotope labelled internal standards for the calibration of each analogue. The analogues, 25-hydroxyD3 (25(OH)D3) and its epimer (3-epi-25(OH)D3) were chromatographically resolved, to prevent over-estimation of 25(OH)D3. The method was validated and subsequently applied for the measurement of total vitamin D levels in human, cow, mare, goat and sheep milk samples. The detection limits, repeatability standard deviations, and recovery ranges were from 0.2 to 0.4 femtomols, 6.30-13.5%, and 88.2-105%, respectively.

  12. Maternal Vitamin D Levels and the Autism Phenotype among Offspring

    ERIC Educational Resources Information Center

    Whitehouse, Andrew J. O.; Holt, Barbara J.; Serralha, Michael; Holt, Patrick G.; Hart, Prue H.; Kusel, Merci M. H.

    2013-01-01

    We tested whether maternal vitamin D insufficiency during pregnancy is related to the autism phenotype. Serum 25(OH)-vitamin D concentrations of 929 women were measured at 18 weeks' pregnancy. The mothers of the three children with a clinical diagnosis of autism spectrum disorder had 25(OH)-vitamin D concentrations above the population mean.…

  13. Selective regulation of Mmp13 by 1,25(OH)2D3, PTH, and Osterix through distal enhancers.

    PubMed

    Meyer, Mark B; Benkusky, Nancy A; Onal, Melda; Pike, J Wesley

    2016-11-01

    Matrix metalloproteinase 13 (MMP13, collagenase-3) is a vital component for chondrocyte and osteoblast maturation, and is aberrantly expressed in numerous disease states. At the transcriptional level, Mmp13 is controlled by many different growth factors and hormones. Most notably, Mmp13 is regulated by the vitamin D hormone (1,25(OH)2D3), parathyroid hormone (PTH), and several cytokines. These activities occur through participation by the transcription factors VDR, RUNX2, FOS, JUN, and Osterix (OSX), respectively. Recently, we discovered that Mmp13 is regulated by elements quite distal to the transcriptional start site -10, -20, and -30kb upstream. These enhancers, along with minor contributions from the region proximal to the promoter, are responsible for the ligand inducible and, most strikingly, the basal activities of Mmp13 gene regulation. Here, we found that the actions of PTH and OSX do not occur through the -10kb VDR bound enhancer. Rather, the -30kb RUNX2 bound enhancer and the promoter proximal regions were essential for activity. Through RUNX2 deletion and OSX overexpression in cells, we showed a specific role for OSX in Mmp13 regulation. Finally, we created an in vivo CRISPR deleted -10kb enhancer mouse model. Despite normal bone density and growth, they fail to up-regulate Mmp13 in response to 1,25(OH)2D3. These data are consistent with those obtained through UAMS osteoblast cell culture and further define the specific roles of distal enhancers in the regulation of Mmp13.

  14. Influence of Vitamin D Binding Protein on Accuracy of 25-Hydroxyvitamin D Measurement Using the ADVIA Centaur Vitamin D Total Assay

    PubMed Central

    Freeman, James; Wilson, Kimberly; Spears, Ryan; Shalhoub, Victoria; Sibley, Paul

    2014-01-01

    Vitamin D status in different populations relies on accurate measurement of total serum 25-hydroxyvitamin D [25(OH)D] concentrations [i.e., 25(OH)D3 and 25(OH)D2]. This study evaluated agreement between the ADVIA Centaur Vitamin D Total assay for 25(OH)D testing (traceable to the NIST-Ghent reference method procedure) and a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for various populations with different levels of vitamin D binding protein (DBP). Total serum 25(OH)D concentrations were measured for 36 pregnant women, 40 hemodialysis patients, and 30 samples (DBP-spiked or not) from healthy subjects. ELISA measured DBP levels. The mean serum DBP concentrations were higher for pregnancy (415 μg/mL) and lower for hemodialysis subjects (198 μg/mL) than for healthy subjects and were highest for spiked serum (545 μg/mL). The average bias between the ADVIA Centaur assay and the LC-MS/MS method was −1.4% (healthy), −6.1% (pregnancy), and 4.4% (hemodialysis). The slightly greater bias for samples from some pregnancy and hemodialysis subjects with serum DBP levels outside of the normal healthy range fell within a clinically acceptable range—reflected by analysis of their low-range (≤136 μg/mL), medium-range (137–559 μg/mL), and high-range (≥560 μg/mL) DBP groups. Thus, the ADVIA Centaur Vitamin D Total assay demonstrates acceptable performance compared with an LC-MS/MS method for populations containing different amounts of DBP. PMID:25045351

  15. Characterization of the cytokine pattern of porcine bone marrow-derived cells treated with 1alpha,25(OH)D.

    PubMed

    Sipos, W; Duvigneau, J C; Schmoll, F; Exel, B; Hofbauer, G; Baravalle, G; Hartl, R T; Dobretsberger, M; Pietschmann, P

    2005-10-01

    The biologically active form of vitamine D(3) [1alpha,25(OH)(2)D(3)] has recently been described not only to influence bone metabolism but also to exert immunomodulating activities, which may have an impact on bone formation/resorption as well. In this study, we analysed the effects of 1alpha,25(OH)(2)D(3) on the cytokine pattern of porcine bone marrow-derived cells from piglets aged 1-3 weeks. After culture for 1 week, the number of osteoclasts was determined, with tartrate-resistant acid phosphatase (TRAP)-positive, multinucleated cells being considered osteoclasts. Cultured bone marrow cell-derived mRNA was subjected to semiquantitative RT-PCR specific for a panel of porcine cytokines (IL-1alpha, IL-6, IL-8, IL-10, and TNF-alpha). In addition, an immunofluorescence analysis using anti-porcine mAbs specific for IL-1beta, IL-2, IL-4, IL-6, IL-12, TNF-alpha, and IFN-gamma was performed. In order to prove the existence of a porcine homologue of the receptor activator of NF-kappaB ligand (RANKL) bone marrow cell- as well as porcine white blood cell-derived mRNA was investigated by RT-PCR using primer pairs specific for murine RANKL. Cell culture supernatant was analysed for soluble RANKL by means of an ELISA designed for quantification of human RANKL. By means of RT-PCR, expression of IL-1alpha, IL-6, IL-8, IL-10 and TNF-alpha mRNA could be found in cells cultured with and without 1alpha,25(OH)(2)D(3). Immunofluorescence analysis revealed that IL-1, IL-6, and TNF-alpha were produced by both stromal cells and osteoclasts. Besides its known osteoclastogenic effects, 1alpha,25(OH)(2)D(3) tended to downregulate the respective cytokines, but significantly upregulated RANKL expression. The homology between the porcine RANKL-specific sequence and the corresponding human RANKL sequence was 79%. The data found support the idea that porcine bone marrow cell cultures may provide a suitable alternative to murine systems in human osteological research.

  16. Vitamin D3 supplementation increases fibroblast growth factor-23 in HIV-infected youth treated with tenofovir disoproxil fumarate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Tenofovir (TDF) is associated with phosphaturia and elevated 1,25 dihydroxy vitamin D (1,25-OH(2)D). Fibroblast growth factor-23 causes phosphaturia and increases in response to elevated 1,25-OH(2)D. Vitamin D binding proetin (VDBP) binds to 1,25-OH(2)D, decreasing biologic activity, and is elevated...

  17. Vitamin D Supplementation increases fibroblast growth factor-23 in HIV-infected youth treated with tenofovir disoproxil fumarate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    BACKGROUND: Tenofovir (TDF) is associated with phosphaturia and elevated 1,25 dihydroxy vitamin D (1,25-OH(2)D). Fibroblast growth factor 23 (FGF23) causes phosphaturia and increases in response to elevated 1,25-OH(2)D. Vitamin D binding protein (VDBP) binds to 1,25-OH(2)D, decreasing its biologic...

  18. The Effect of 1α,25(OH)2D3 on Osteogenic Differentiation of Stem Cells from Dental Pulp of Exfoliated Deciduous Teeth

    PubMed Central

    Mojarad, Farzad; Amiri, Iraj; Rafatjou, Rezvan; Janeshin, Atousa; Farhadian, Maryam

    2016-01-01

    Statement of the Problem: Stem cells from human exfoliated deciduous teeth (SHEDs) are a population of highly proliferative cells, being capable of differentiating into osteogenic, odontogenic, adipocytes, and neural cells. Vitamin D3 metabolites such as 1α, 25-dihydroxyvitamin D3 are key factors in the regulation of bone metabolism. Purpose: The aim of this study was to investigate the effect of 1α, 25-dihydroxyvitamin D3 on osteogenic differentiation (alkaline phosphatase activity and alizarin red staining) of stem cells of exfoliated deciduous teeth. Materials and Method: Dental pulp was removed from freshly extracted primary teeth and immersed in a digestive solution. Then, the dental pulp cells were immersed in α-MEM (minimum essential medium) to which 10% fetal bovine serum was added. After the third passage, the cells were isolated from the culture plate and were used for osteogenic differentiation. As a control group, the cells were cultured in osteogenic cell culture medium. As the case group, the cells were cultured in osteogenic culture medium supplemented with 100 nM 1α,25 (OH)2D3. The alkaline phosphatase (ALP) activity and alizarin red staining were analyzed to evaluate the osteogenic differentiation at day 21. The results were analyzed by using t-test. Results: Compared with the control group, significant increase was observed in ALP activity of SHEDs after being treated with 1α,25(OH)2D3 (p= 0.002). Alizarin red staining demonstrated that the cells exposed to 1α,25(OH)2D3 induced higher mineralized nodules (p< 0.001). Conclusion: Osteoblast differentiation in SHEDs was stimulated by 1α,25(OH) 2D3. It can be concluded that 1α,25(OH)2D3 can improve osteoblastic differentiation. PMID:27942551

  19. Vitamin D–Binding Protein Modifies the Vitamin D–Bone Mineral Density Relationship

    PubMed Central

    Powe, Camille E; Ricciardi, Catherine; Berg, Anders H; Erdenesanaa, Delger; Collerone, Gina; Ankers, Elizabeth; Wenger, Julia; Karumanchi, S Ananth; Thadhani, Ravi; Bhan, Ishir

    2011-01-01

    Studies examining the relationship between total circulating 25-hydroxyvitamin D [25(OH)D] levels and bone mineral density (BMD) have yielded mixed results. Vitamin D–binding protein (DBP), the major carrier protein for 25(OH)D, may alter the biologic activity of circulating vitamin D. We hypothesized that free and bioavailable 25(OH)D, calculated from total 25(OH)D, DBP, and serum albumin levels, would be more strongly associated with BMD than levels of total 25(OH)D. We measured total 25(OH)D, DBP, and serum albumin levels in 49 healthy young adults enrolled in the Metabolic Abnormalities in College-Aged Students (MACS) study. Lumbar spine BMD was measured in all subjects using dual-energy X-ray absorptiometry. Clinical, diet, and laboratory information also was gathered at this time. We determined free and bioavailable (free + albumin-bound) 25(OH)D using previously validated formulas and examined their associations with BMD. BMD was not associated with total 25(OH)D levels (r = 0.172, p = .236). In contrast, free and bioavailable 25(OH)D levels were positively correlated with BMD (r = 0.413, p = .003 for free, r = 0.441, p = .002 for bioavailable). Bioavailable 25(OH)D levels remained independently associated with BMD in multivariate regression models adjusting for age, sex, body mass index, and race (p = .03). It is concluded that free and bioavailable 25(OH)D are more strongly correlated with BMD than total 25(OH)D. These findings have important implications for vitamin D supplementation in vitamin D–deficient states. Future studies should continue to explore the relationship between free and bioavailable 25(OH)D and health outcomes. © 2011 American Society for Bone and Mineral Research. PMID:21416506

  20. Effects of 1,25(OH)2D3 on Cancer Cells and Potential Applications in Combination with Established and Putative Anti-Cancer Agents

    PubMed Central

    Abu el Maaty, Mohamed A.; Wölfl, Stefan

    2017-01-01

    The diverse effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), the bio-active form of vitamin D, on cancer cell metabolism and proliferation has made it an interesting candidate as a supporting therapeutic option in cancer treatment. An important strategy in cancer therapy is the use of combination chemotherapy to overcome drug resistance associated with numerous anti-cancer agents and to provide better means of avoiding undesirable side effects. This complex strategy is widely adopted by oncologists and several established “cocktails” of chemotherapeutics are routinely administered to cancer patients. Among the principles followed in designing such treatment regimens is the use of drugs with different mechanisms of action to overcome the issue of tumor heterogeneity and to evade resistance. In light of the profound and diverse effects of 1,25(OH)2D3 reported by in vitro and in vivo studies, we discuss how these effects could support the use of this molecule in combination with “classical” cytotoxic drugs, such as platins and anti-metabolites, for the treatment of solid and hematological tumors. We also examine recent evidence supporting synergistic activities with other promising anti-cancer drug candidates, and postulate mechanisms through which 1,25(OH)2D3 may help evade chemoresistance. PMID:28124999

  1. Association between vitamin D and hepatitis C virus infection: A meta-analysis

    PubMed Central

    Villar, Livia Melo; Del Campo, José Antonio; Ranchal, Isidora; Lampe, Elisabeth; Romero-Gomez, Manuel

    2013-01-01

    AIM: To evaluate the association between 25-hydroxyvitamin D [25(OH)D] and sustained virological response (SVR) in hepatitis C virus (HCV) infected individuals. METHODS: Relevant studies were identified by systematically searching MEDLINE databases up to March 2012 and abstracts of the European and American Congress of Hepatology conducted in 2011. Studies must provide information on SVR and the levels of 25(OH)D3 and/or 25(OH)D2 [henceforth referred to as 25(OH)D] in sera samples from HCV infected individuals. The inclusion criteria were: clinical studies that included HCV infected patients aged older than 18 years regardless of HCV genotype or ethnic group; provided information on SVR rates; and were reported in the English language as full papers. Due to the heterogeneity of studies in categorizing serum vitamin D levels, a cut-off value of 30 ng/mL of serum 25(OH)D was used. Heterogeneity was assessed using I2 statistics. The summary odds ratios with their corresponding 95%CI were calculated based on a random-effects model. RESULTS: Overall, 11 studies (8 observational and 3 interventional) involving 1575 individuals were included and 1117 HCV infected individuals (71%) showed low vitamin D levels. Most of the studies included mono-infected HCV individuals with the mean age ranging from 38 to 56 years. Four studies were conducted in human immunodeficiency virus/HCV infected individuals. Regarding vitamin D measurement, most of the studies employed radioimmunoassays (n = 5) followed by chemiluminescence (n = 4) and just one study employed high performance/pressure liquid chromatography (HPLC). Basal vitamin D levels varied from 17 to 43 ng/mL in the studies selected, and most of the HCV infected individuals had genotype 1 (1068/1575) with mean viral load varying from log 4.5-5.9 UI/mL. With regard to HCV treatment, most of the studies (n = 8) included HCV individuals without previous treatment, where the pooled SVR rate was 46.4%. High rates of SVR were observed

  2. Vitamin D: calcium and bone homeostasis during evolution

    PubMed Central

    Bouillon, Roger; Suda, Tatsuo

    2014-01-01

    Vitamin D3 is already found early in the evolution of life but essentially as inactive end products of the photochemical reaction of 7-dehydrocholestol with ultraviolet light B. A full vitamin D (refers to vitamin D2 and D3) endocrine system, characterized by a specific VDR (vitamin D receptor, member of the nuclear receptor family), specific vitamin D metabolizing CYP450 enzymes regulated by calciotropic hormones and a dedicated plasma transport-protein is only found in vertebrates. In the earliest vertebrates (lamprey), vitamin D metabolism and VDR may well have originated from a duplication of a common PRX/VDR ancestor gene as part of a xenobiotic detoxification pathway. The vitamin D endocrine system, however, subsequently became an important regulator of calcium supply for an extensive calcified skeleton. Vitamin D is essential for normal calcium and bone homeostasis as shown by rickets in vitamin D-deficient growing amphibians, reptiles, birds and mammals. From amphibians onward, bone is gradually more dynamic with regulated bone resorption, mainly by combined action of PTH and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the generation and function of multinucleated osteoclasts. Therefore, bone functions as a large internal calcium reservoir, under the control of osteoclasts. Osteocytes also display a remarkable spectrum of activities, including mechanical sensing and regulating mineral homeostasis, but also have an important role in global nutritional and energy homeostasis. Mineralization from reptiles onward is under the control of well-regulated SIBLING proteins and associated enzymes, nearly all under the control of 1,25(OH)2D3. The vitamin D story thus started as inert molecule but gained an essential role for calcium and bone homeostasis in terrestrial animals to cope with the challenge of higher gravity and calcium-poor environment. PMID:24466411

  3. Vitamin D: calcium and bone homeostasis during evolution.

    PubMed

    Bouillon, Roger; Suda, Tatsuo

    2014-01-08

    Vitamin D3 is already found early in the evolution of life but essentially as inactive end products of the photochemical reaction of 7-dehydrocholestol with ultraviolet light B. A full vitamin D (refers to vitamin D2 and D3) endocrine system, characterized by a specific VDR (vitamin D receptor, member of the nuclear receptor family), specific vitamin D metabolizing CYP450 enzymes regulated by calciotropic hormones and a dedicated plasma transport-protein is only found in vertebrates. In the earliest vertebrates (lamprey), vitamin D metabolism and VDR may well have originated from a duplication of a common PRX/VDR ancestor gene as part of a xenobiotic detoxification pathway. The vitamin D endocrine system, however, subsequently became an important regulator of calcium supply for an extensive calcified skeleton. Vitamin D is essential for normal calcium and bone homeostasis as shown by rickets in vitamin D-deficient growing amphibians, reptiles, birds and mammals. From amphibians onward, bone is gradually more dynamic with regulated bone resorption, mainly by combined action of PTH and 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) on the generation and function of multinucleated osteoclasts. Therefore, bone functions as a large internal calcium reservoir, under the control of osteoclasts. Osteocytes also display a remarkable spectrum of activities, including mechanical sensing and regulating mineral homeostasis, but also have an important role in global nutritional and energy homeostasis. Mineralization from reptiles onward is under the control of well-regulated SIBLING proteins and associated enzymes, nearly all under the control of 1,25(OH)2D3. The vitamin D story thus started as inert molecule but gained an essential role for calcium and bone homeostasis in terrestrial animals to cope with the challenge of higher gravity and calcium-poor environment.

  4. Effect of 1,25-(OH)2D3 and lipopolysaccharide on mononuclear cell inflammation in type 2 diabetes mellitus and diabetic nephropathy uremia.

    PubMed

    Wu, E L; Cui, H X

    2016-08-29

    The prevention and treatment of type-2 diabetes mellitus (T2DM) and diabetic nephropathy (DN), which are disorders with high incidence rates, is of primary importance. In this study, we analyzed the effect of 1,25-(OH)2D3 and lipopolysaccharide (LPS) in combination with interleukin (IL)-15 on the inflammatory immune response and expression of vitamin D receptor (VDR) in mononuclear cells of T2DM and DN uremia (DNU) patients. The human acute monocytic leukemia cell line THP-1 was treated with peripheral blood serum isolated from 30 healthy controls and T2DM and DNU patients each, cultured in the presence or absence of 1,25-(OH)2D3, and subsequently treated with LPS and IL-15. The VDR mRNA and protein expression in THP-1 cells was detected by real-time polymerase chain reaction and western blot (and immunofluorescence assay), respectively, and IL-6 and IL-10 concentrations in the culture supernatant were detected by enzyme-linked immunosorbent assay. LPS treatment induced a significant decrease in VDR mRNA expression in T2DM and DNU serum-treated THP-1 cells compared to the control cells (P < 0.05). The VDR protein expression in DNU serum-treated THP-1 cells was also significantly down-regulated (P < 0.05). LPS treatment induced IL-6 secretion in serum-treated THP-1 cells (P < 0.05), while 1,25-(OH)2D3 treatment inhibited IL-6 secretion to some extent. These findings suggested that LPS down-regulates the expression of VDR in mononuclear cells of T2DM and DNU patients and induces an imbalance in the pro-inflammatory and anti-inflammatory cytokine response, while 1,25-(OH)2D3 partially reversed the effect of LPS and protected patients with T2DM and DNU.

  5. Vitamin D Enhances Corneal Epithelial Barrier Function

    PubMed Central

    Yin, Zhaohong; Pintea, Victorina; Lin, Yanping; Hammock, Bruce D.

    2011-01-01

    Purpose. The purpose of this study was to determine whether 25-hydroxyvitamin D3 (25(OH)D3) and/or its active metabolite, 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3), can enhance corneal epithelial barrier function. The authors also determined if corneas contain mRNA for the vitamin D receptor (VDR) and 1α-hydroxylase, the enzyme required to convert 25(OH)D3 to 1,25(OH)2D3, and measured vitamin D metabolite concentrations in aqueous and vitreous humor. Methods. RT-PCR was used to examine mouse, rabbit, and human corneal epithelial VDR and 1α-hydroxylase mRNA. Vitamin D metabolites were measured using a selective vitamin D derivatizing agent and mass spectroscopy. Barrier function experiments were performed by measuring inulin permeability (IP) and/or transepithelial resistance (TER) in control, 25(OH)D3-, and 1,25(OH)2D3-treated human and rabbit corneal epithelial monolayers cultured on permeable inserts. Ca2+ was removed, then reintroduced to the culture medium while IP and TER readings were taken. Occludin levels were examined using Western blotting. Results. All corneal samples were positive for both VDR and 1α-hydroxylase mRNA. All vitamin D metabolites except for unhydroxylated vitamin D3 were detected in aqueous and vitreous humor. Epithelial cells showed increased TER, decreased IP, and increased occludin levels when cultured with 25(OH)D3 and 1,25(OH)2D3. Conclusions. We conclude that corneas contain mRNA for VDR and 1α-hydroxylase as well as significant vitamin D concentrations. 25(OH)D3 and its active metabolite 1,25(OH)2D3, both enhance corneal epithelial barrier function. PMID:21715350

  6. 24R,25-dihydroxyvitamin D3 [24R,25(OH)2D3] controls growth plate development by inhibiting apoptosis in the reserve zone and stimulating response to 1alpha,25(OH)2D3 in hypertrophic cells.

    PubMed

    Boyan, B D; Hurst-Kennedy, J; Denison, T A; Schwartz, Z

    2010-07-01

    Previously we showed that costochondral growth plate resting zone (RC) chondrocytes response primarily to 24R,25(OH)2D3 whereas prehypertrophic and hypertrophic (GC) cells respond to 1alpha,25(OH)2D3. 24R,25(OH)2D3 increases RC cell proliferation and inhibits activity of matrix processing enzymes, suggesting it stabilizes cells in the reserve zone, possibly by inhibiting the matrix degradation characteristic of apoptotic hypertrophic GC cells. To test this, apoptosis was induced in rat RC cells by treatment with exogenous inorganic phosphate (Pi). 24R,25(OH)2D3 blocked apoptotic effects in a dose-dependent manner. Similarly, apoptosis was induced in ATDC5 cell cultures and 24R,25(OH)2D3 blocked this effect. Further studies indicated that 24R,25(OH)2D3 acts via at least two independent pathways. 24R,25(OH)2D3 increases LPA receptor-1 (LPA R1) expression and production of lysophosphatidic acid (LPA), and subsequent LPA R1/3-dependent signaling, thereby decreasing p53 abundance. LPA also increases the Bcl-2/Bax ratio. In addition, 24R,25(OH)2D3 acts by increasing PKC activity. 24R,25(OH)2D3 stimulates 1-hydroxylase activity, resulting in increased levels of 1,25(OH)2D3, and it increases levels of phospholipase A2 activating protein, which is required for rapid 1alpha,25(OH)2D3-dependent activation of PKC in GC cells. These results suggest that 24R,25(OH)2D3 modulates growth plate development by controlling the rate and extent of RC chondrocyte transition to a GC chondrocyte phenotype.

  7. Vitamin D supplementation guidelines.

    PubMed

    Pludowski, Pawel; Holick, Michael F; Grant, William B; Konstantynowicz, Jerzy; Mascarenhas, Mario R; Haq, Afrozul; Povoroznyuk, Vladyslav; Balatska, Nataliya; Barbosa, Ana Paula; Karonova, Tatiana; Rudenka, Ema; Misiorowski, Waldemar; Zakharova, Irina; Rudenka, Alena; Łukaszkiewicz, Jacek; Marcinowska-Suchowierska, Ewa; Łaszcz, Natalia; Abramowicz, Pawel; Bhattoa, Harjit P; Wimalawansa, Sunil J

    2017-02-12

    Research carried out during the past two-decades extended the understanding of actions of vitamin D, from regulating calcium and phosphate absorption and bone metabolism to many pleiotropic actions in organs and tissues in the body. Most observational and ecological studies report association of higher serum 25-hydroxyvitamin D [25(OH)D] concentrations with improved outcomes for several chronic, communicable and non-communicable diseases. Consequently, numerous agencies and scientific organizations have developed recommendations for vitamin D supplementation and guidance on optimal serum 25(OH)D concentrations. The bone-centric guidelines recommend a target 25(OH)D concentration of 20ng/mL (50nmol/L), and age-dependent daily vitamin D doses of 400-800IU. The guidelines focused on pleiotropic effects of vitamin D recommend a target 25(OH)D concentration of 30ng/mL (75nmol/L), and age-, body weight-, disease-status, and ethnicity dependent vitamin D doses ranging between 400 and 2000IU/day. The wise and balanced choice of the recommendations to follow depends on one's individual health outcome concerns, age, body weight, latitude of residence, dietary and cultural habits, making the regional or nationwide guidelines more applicable in clinical practice. While natural sources of vitamin D can raise 25(OH)D concentrations, relative to dietary preferences and latitude of residence, in the context of general population, these sources are regarded ineffective to maintain the year-round 25(OH)D concentrations in the range of 30-50ng/mL (75-125nmol/L). Vitamin D self-administration related adverse effects, such as hypercalcemia and hypercalciuria are rare, and usually result from taking extremely high doses of vitamin D for a prolonged time.

  8. PT19c, Another Nonhypercalcemic Vitamin D2 Derivative, Demonstrates Antitumor Efficacy in Epithelial Ovarian and Endometrial Cancer Models

    PubMed Central

    Kawar, Nada; Maclaughlan, Shannon; Horan, Timothy C.; Uzun, Alper; Lange, Thilo S.; Kim, Kyu K.; Hopson, Russell; Singh, Ajay P.; Sidhu, Preetpal S.; Glass, Kyle A.; Shaw, Sunil; Padbury, James F.; Vorsa, Nicholi; Arnold, Leggy A.; Moore, Richard G.; Brard, Laurent

    2013-01-01

    Hypercalcemia remains a major impediment to the clinical use of vitamin D in cancer treatment. Approaches to remove hypercalcemia and development of nonhypercalcemic agents can lead to the development of vitamin D–based therapies for treatment of various cancers. In this report, in vitro and in vivo anticancer efficacy, safety, and details of vitamin D receptor (VDR) interactions of PT19c, a novel nonhypercalcemic vitamin D derived anticancer agent, are described. PT19c was synthesized by bromoacetylation of PTAD-ergocalciferol adduct. Broader growth inhibitory potential of PT19c was evaluated in a panel of chemoresistant breast, renal, ovarian, lung, colon, leukemia, prostate, melanoma, and central nervous system cancers cell line types of NCI60 cell line panel. Interactions of PT19c with VDR were determined by a VDR transactivation assay in a VDR overexpressing VDR-UAS-bla-HEK293 cells, in vitro VDR-coregulator binding, and molecular docking with VDR-ligand binding domain (VDR-LBD) in comparison with calcitriol. Acute toxicity of PT19c was determined in nontumored mice. In vivo antitumor efficacy of PT19c was determined via ovarian and endometrial cancer xenograft experiments. Effect of PT19c on actin filament organization and focal adhesion formation was examined by microscopy. PT19c treatment inhibited growth of chemoresistant NCI60 cell lines (log10GI50 ~ −4.05 to −6.73). PT19c (10 mg/kg, 35 days) reduced growth of ovarian and endometrial xenograft tumor without hypercalcemia. PT19c exerted no acute toxicity up to 400 mg/kg (QDx1) in animals. PT19c showed weak VDR antagonism, lack of VDR binding, and inverted spatial accommodation in VDR-LBD. PT19c caused actin filament dysfunction and inhibited focal adhesion in SKOV-3 cells. PT19c is a VDR independent nonhypercalcemic vitamin D–derived agent that showed noteworthy safety and efficacy in ovarian and endometrial cancer animal models and inhibited actin organization and focal adhesion in ovarian cancer

  9. PT19c, Another Nonhypercalcemic Vitamin D2 Derivative, Demonstrates Antitumor Efficacy in Epithelial Ovarian and Endometrial Cancer Models.

    PubMed

    Kawar, Nada; Maclaughlan, Shannon; Horan, Timothy C; Uzun, Alper; Lange, Thilo S; Kim, Kyu K; Hopson, Russell; Singh, Ajay P; Sidhu, Preetpal S; Glass, Kyle A; Shaw, Sunil; Padbury, James F; Vorsa, Nicholi; Arnold, Leggy A; Moore, Richard G; Brard, Laurent; Singh, Rakesh K

    2013-11-01

    Hypercalcemia remains a major impediment to the clinical use of vitamin D in cancer treatment. Approaches to remove hypercalcemia and development of nonhypercalcemic agents can lead to the development of vitamin D-based therapies for treatment of various cancers. In this report, in vitro and in vivo anticancer efficacy, safety, and details of vitamin D receptor (VDR) interactions of PT19c, a novel nonhypercalcemic vitamin D derived anticancer agent, are described. PT19c was synthesized by bromoacetylation of PTAD-ergocalciferol adduct. Broader growth inhibitory potential of PT19c was evaluated in a panel of chemoresistant breast, renal, ovarian, lung, colon, leukemia, prostate, melanoma, and central nervous system cancers cell line types of NCI60 cell line panel. Interactions of PT19c with VDR were determined by a VDR transactivation assay in a VDR overexpressing VDR-UAS-bla-HEK293 cells, in vitro VDR-coregulator binding, and molecular docking with VDR-ligand binding domain (VDR-LBD) in comparison with calcitriol. Acute toxicity of PT19c was determined in nontumored mice. In vivo antitumor efficacy of PT19c was determined via ovarian and endometrial cancer xenograft experiments. Effect of PT19c on actin filament organization and focal adhesion formation was examined by microscopy. PT19c treatment inhibited growth of chemoresistant NCI60 cell lines (log10GI50 ~ -4.05 to -6.73). PT19c (10 mg/kg, 35 days) reduced growth of ovarian and endometrial xenograft tumor without hypercalcemia. PT19c exerted no acute toxicity up to 400 mg/kg (QDx1) in animals. PT19c showed weak VDR antagonism, lack of VDR binding, and inverted spatial accommodation in VDR-LBD. PT19c caused actin filament dysfunction and inhibited focal adhesion in SKOV-3 cells. PT19c is a VDR independent nonhypercalcemic vitamin D-derived agent that showed noteworthy safety and efficacy in ovarian and endometrial cancer animal models and inhibited actin organization and focal adhesion in ovarian cancer cells.

  10. Determination of vitamins D2 and D3 in infant formula and adult nutritionals by ultra-pressure liquid chromatography with tandem mass spectrometry detection (UPLC-MS/MS): First Action 2011.12.

    PubMed

    Stevens, Jack; Dowell, Dawn

    2012-01-01

    The method for the "Determination of Vitamins D2 and D3 in Infant Formula and Adult Nutritionals by Ultra-Pressure Liquid Chromatography with Tandem Mass Spectrometry Detection (UPLC-MS/MS)" was adopted as AOAC Official First Action during the "Standards Development and International Harmonization: AOAC INTERNATIONAL Mid-Year Meeting" held June 29, 2011. During the meeting, an Expert Review Panel (ERP) evaluated the available validation information against standard method performance requirements (SMPRs) articulated by stakeholders. The method, approved by the ERP, is applicable for the determination of vitamin D (total vitamins D2 and D3). A range of products had been tested during a single-laboratory validation study. The products included butter, National Institute of Standards and Technology SRM 1849, eggs, cheese, yogurt, ready-to-eat cereal, bread, mushrooms, and tuna. The testing of the method established linearity in the range of 0.005-50 microg/mL. The recovery range was 93.4-100.9% for vitamin D2 and 102.4-106.2% for vitamin D3. The LOD and LOQ for vitamin D2 were reported as 0.20 and 0.61 microgl100 g, respectively; for vitamin D3, the reported values were 0.47 and 1.44 microg/100 g, respectively. The method met the SMPRs set by the Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN). It was, therefore, decided that the method was appropriate for Official First Action Method status.

  11. On-line SPE sample treatment as a tool for method automatization and detection limits reduction: Quantification of 25-hydroxyvitamin D3/D2.

    PubMed

    Palaiogiannis, Dimitrios; Bekou, Evangelia; Pazaitou-Panayiotou, Kalliopi; Samanidou, Victoria; Tsakalof, Andreas

    2017-02-01

    The development and approbation of new, automated UHPLC-DAD method for the quantification of 25-hydroxyvitamin D3/D2 (25OH-D3/D2) metabolites in plasma/serum for the evaluation of patient's vitamin D status are presented. The method was developed on the Ultimate 3000 UHPLC dual gradient system supplied with the on-line SPE-concentration column coupled through six port switching valve to analytical column. This configuration and materials selected enable large volume sample injection (500μL) and on-line sample preconcentration, clean up and subsequent selective metabolites transfer onto the analytical column. The new method abrogates main conventional time consuming and error source off-line steps of analysis and thus simplifies analysis. The large volume injection increases the sensitivity of instrumental analysis by about ten-fold on-line pre-concentration of metabolites. The instrument response is linear (R>0.99) in the investigated concentration range 10-100ngmL(-1) which covers all the possible vitamin D status from serious deficiency (<12ngmL(-1)) to excess. The method detection limits (S/N=3) are LOD (25OH-D3)=0.94ngmL(-1) and LOD (25OH-D2)=2.4ngmL(-1). The method performance was assessed with the use of certified reference samples and perfect agreement between certified and measured values is demonstrated. The method was applied to human samples previously analyzed for total vitamin D by Competitive Protein-binding assay and findings of the two methods are compared.

  12. High throughput LC-MS/MS method for the simultaneous analysis of multiple vitamin D analytes in serum

    PubMed Central

    Jenkinson, Carl; Adams, John S.; Stewart, Paul M.; Hewison, Martin; Keevil, Brian G.

    2016-01-01

    Recent studies suggest that vitamin D-deficiency is linked to increased risk of common human health problems. To define vitamin D ‘status’ most routine analytical methods quantify one particular vitamin D metabolite, 25-hydroxyvitamin D3 (25OHD3). However, vitamin D is characterized by complex metabolic pathways, and simultaneous measurement of multiple vitamin D metabolites may provide a more accurate interpretation of vitamin D status. To address this we developed a high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyse multiple vitamin D analytes, with particular emphasis on the separation of epimer metabolites. A supportive liquid-liquid extraction (SLE) and LC-MS/MS method was developed to quantify 10 vitamin D metabolites as well as separation of an interfering 7α-hydroxy-4-cholesten-3-one (7αC4) isobar (precursor of bile acid), and validated by analysis of human serum samples. In a cohort of 116 healthy subjects, circulating concentrations of 25-hydroxyvitamin D3 (25OHD3), 3-epi-25-hydroxyvitamin D3 (3-epi-25OHD3), 24,25-dihydroxyvitamin D3 (24R,25(OH)2D3), 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), and 25-hydroxyvitamin D2 (25OHD2) were quantifiable using 220 μl of serum, with 25OHD3 and 24R,25(OH)2D3 showing significant seasonal variations. This high-throughput LC-MS/MS method provides a novel strategy for assessing the impact of vitamin D on human health and disease. PMID:26874878

  13. High throughput LC-MS/MS method for the simultaneous analysis of multiple vitamin D analytes in serum.

    PubMed

    Jenkinson, Carl; Taylor, Angela E; Hassan-Smith, Zaki K; Adams, John S; Stewart, Paul M; Hewison, Martin; Keevil, Brian G

    2016-03-01

    Recent studies suggest that vitamin D-deficiency is linked to increased risk of common human health problems. To define vitamin D 'status' most routine analytical methods quantify one particular vitamin D metabolite, 25-hydroxyvitamin D3 (25OHD3). However, vitamin D is characterized by complex metabolic pathways, and simultaneous measurement of multiple vitamin D metabolites may provide a more accurate interpretation of vitamin D status. To address this we developed a high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to analyse multiple vitamin D analytes, with particular emphasis on the separation of epimer metabolites. A supportive liquid-liquid extraction (SLE) and LC-MS/MS method was developed to quantify 10 vitamin D metabolites as well as separation of an interfering 7α-hydroxy-4-cholesten-3-one (7αC4) isobar (precursor of bile acid), and validated by analysis of human serum samples. In a cohort of 116 healthy subjects, circulating concentrations of 25-hydroxyvitamin D3 (25OHD3), 3-epi-25-hydroxyvitamin D3 (3-epi-25OHD3), 24,25-dihydroxyvitamin D3 (24R,25(OH)2D3), 1,25-dihydroxyvitamin D3 (1α,25(OH)2D3), and 25-hydroxyvitamin D2 (25OHD2) were quantifiable using 220μL of serum, with 25OHD3 and 24R,25(OH)2D3 showing significant seasonal variations. This high-throughput LC-MS/MS method provides a novel strategy for assessing the impact of vitamin D on human health and disease.

  14. Application of dried blood spots to determine vitamin D status in a large nutritional study with unsupervised sampling: the Food4Me project.

    PubMed

    Hoeller, Ulrich; Baur, Manuela; Roos, Franz F; Brennan, Lorraine; Daniel, Hannelore; Fallaize, Rosalind; Forster, Hannah; Gibney, Eileen R; Gibney, Mike; Godlewska, Magdalena; Hartwig, Kai; Kolossa, Silvia; Lambrinou, Christina P; Livingstone, Katherine M; Lovegrove, Julie A; Macready, Anna L; Manios, Yannis; Marsaux, Cyril F M; Martinez, J Alfredo; Celis-Morales, Carlos; Moschonis, George; Navas-Carretero, Santiago; O'Donovan, Clare B; San-Cristobal, Rodrigo; Saris, Wim H M; Surwiłło, Agnieszka; Traczyk, Iwona; Tsirigoti, Lydia; Walsh, Marianne C; Woolhead, Clara; Mathers, John C; Weber, Peter

    2016-01-28

    An efficient and robust method to measure vitamin D (25-hydroxy vitamin D3 (25(OH)D3) and 25-hydroxy vitamin D2 in dried blood spots (DBS) has been developed and applied in the pan-European multi-centre, internet-based, personalised nutrition intervention study Food4Me. The method includes calibration with blood containing endogenous 25(OH)D3, spotted as DBS and corrected for haematocrit content. The methodology was validated following international standards. The performance characteristics did not reach those of the current gold standard liquid chromatography-MS/MS in plasma for all parameters, but were found to be very suitable for status-level determination under field conditions. DBS sample quality was very high, and 3778 measurements of 25(OH)D3 were obtained from 1465 participants. The study centre and the season within the study centre were very good predictors of 25(OH)D3 levels (P<0·001 for each case). Seasonal effects were modelled by fitting a sine function with a minimum 25(OH)D3 level on 20 January and a maximum on 21 July. The seasonal amplitude varied from centre to centre. The largest difference between winter and summer levels was found in Germany and the smallest in Poland. The model was cross-validated to determine the consistency of the predictions and the performance of the DBS method. The Pearson's correlation between the measured values and the predicted values was r 0·65, and the sd of their differences was 21·2 nmol/l. This includes the analytical variation and the biological variation within subjects. Overall, DBS obtained by unsupervised sampling of the participants at home was a viable methodology for obtaining vitamin D status information in a large nutritional study.

  15. Vitamin D expenditure is not altered in pregnancy and lactation despite changes in vitamin D metabolite concentrations

    PubMed Central

    Jones, Kerry S; Assar, Shima; Prentice, Ann; Schoenmakers, Inez

    2016-01-01

    Pregnancy and lactation are associated with changes in vitamin D and calcium metabolism but the impact of these changes on vitamin D expenditure is unknown. We measured plasma 25(OH)D3 half-life with a stable-isotope tracer and investigated relationships with vitamin D metabolites in pregnant, lactating and ‘non-pregnant, non-lactating’ (NPNL) women. Vitamin D metabolites, vitamin D binding protein (DBP), PTH and 25(OH)D3 half-life were measured in third-trimester pregnant women (n22) and repeated during lactation 12 weeks post-partum (n14) and twice in NPNL women (n23 and n10, respectively) in rural Gambia where calcium intakes are low with little seasonality in UVB-exposure. 25(OH)D3 half-life was not significantly different between groups (mean(SD): 20.6(6.8), 22.6(7.7), 18.0(4.7) and 17.7(9.5) days in pregnant, lactating and NPNL women, respectively). Plasma 25(OH)D3, 1,25(OH)2D, and DBP were higher in pregnancy, and calculated free-25(OH)D3 and PTH were lower (P < 0.05). In lactation, 25(OH)D3 and 24,25(OH)2D3 were lower compared to pregnant (P < 0.001, P = 0.02) and NPNL women (P = 0.04, P = 0.07). Significant associations were observed between half-life and 25(OH)D3 (+ve) in pregnancy, and in all groups between 25(OH)D3 and free-25(OH)D3 (+ve) and PTH and 25(OH)D3 (−ve) (P < 0.0001). These data suggest that adaptive changes in pregnancy and lactation occur that prevent pronounced changes in vitamin D expenditure. PMID:27222109

  16. Vitamins

    MedlinePlus

    ... vitamin has specific jobs. If you have low levels of certain vitamins, you may get health problems. For example, if you don't get enough vitamin C, you could become anemic. Some vitamins may help prevent medical problems. Vitamin A prevents night blindness. The best way to get ...

  17. Vitamin D

    PubMed Central

    Grant, William B.; Tangpricha, Vin

    2012-01-01

    Evidence that vitamin D reduces the risk of many types of disease is increasing exponentially. In 2011, 3,100 publications with “vitamin D” in the title or abstract were published, up from 2,606 in 2010, 1,303 in 2005, and 796 in 2000. A committee operating under the auspices of the Institute of Medicine (IOM) of the US National Academies reviewed the evidence for beneficial effects of vitamin D. Their report, issued at the end of 2010,1 found what they considered to be strong evidence for only one health outcome: skeletal health. They considered beneficial evidence only from published randomized controlled trials (RCTs) focused mainly on skeletal health. In contrast, to justify concern about higher vitamin D intake and serum 25(OH)D concentrations, they used data from nested case-control studies reporting U-shaped outcomes of prediagnostic serum 25-hydroxyvitamin D [25(OH)D] for cancer and all-cause mortality rates. They set the daily recommended intake of vitamin D at 600–800 IU for most children and adults and defined vitamin D sufficiency as a serum 25(OH)D level above 20 ng/ml (50 nmol/l). They also set a daily upper intake of 4,000 IU of vitamin D3 and called for more RCTs to determine nonskeletal health effects. As of this writing, more than 130 journal publications have criticized the IOM report as being too conservative. One summarized the problems succinctly: “The IOM recommendations for vitamin D fail in a major way on logic, on science, and on effective public health guidance. Moreover, by failing to use a physiological referent, the IOM approach constitutes precisely the wrong model for development of nutritional policy.”2 PMID:22928061

  18. Retraction: 'Alendronate and vitamin D2 for prevention of hip fracture in Parkinson's disease: A randomized controlled trial,' by Sato, Y., Iwamoto, J., Kanoko, T., and Satoh, K.

    PubMed

    2016-07-01

    The above article, published online on 14 March 2006 in Wiley Online Library (wileyonlinelibrary.com), and in Volume 21, Issue 7, Pages 924-929, has been retracted by agreement between the authors, the Editor-in-Chief, Jose A. Obeso, and Wiley Periodicals, Inc. The retraction has been agreed due to an acknowledgement from the authors that the co-authors did not participate in study design, data collection, data analysis, interpretation of data and drafting the manuscript. Thus all co-authors are honorary. Reference Sato, Y., Iwamoto, J., Kanoko, T., and Satoh, K. (2006) Alendronate and vitamin D2 for prevention of hip fracture in Parkinson's disease: A randomized controlled trial. Mov Disord. doi: 10.1002/mds.20825.

  19. [Vitamin D: skeletal and muscular effects].

    PubMed

    Thomas, Thierry; Briot, Karine

    2013-10-01

    Insufficient serum levels of 25-hydroxyvitamin D [25(OH)D] is a risk factor for osteoporosis. A new paradigm is emerging with the locally synthesized 1,25(OH)2D within osteoblasts and osteoclasts as the essential pathway for the effects of 25(OH)D in regulating bone remodeling via direct or indirect activation of the specific receptor VDR. Vitamin D has positive effects on fracture risk, muscular function and risk of falls; these effects are observed when serum levels of 25(OH)D are above 30 ng/ml (75 nmol/l). Vitamin D dosing interval may be relevant for reducing the risk of fracture, with evidence suggesting positive effects with short intervals of 3 months or less. It is recommended to maintain an optimal serum level of 25(OH)D when managing patients with osteoporosis or at risk of this bone disease.

  20. Differential response to 1α, 25-dihydroxyvitamin D3 (1α,25(OH)2D3) in non-small cell lung cancer cells with distinct oncogene mutations1

    PubMed Central

    Zhang, Qiuhong; Kanterewicz, Beatriz; Shoemaker, Suzanne; Hu, Qiang; Liu, Song; Atwood, Kristopher; Hershberger, Pamela

    2012-01-01

    We previously demonstrated that non-small cell lung cancer (NSCLC) cells and primary human lung tumors aberrantly express the vitamin D3-catabolizing enzyme, CYP24, and that CYP24 restricts transcriptional regulation and growth control by 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) in NSCLC cells. To ascertain the basis for CYP24 dysregulation, we assembled a panel of cell lines that represent distinct molecular classes of lung cancer: Cell lines were selected which harbored mutually exclusive mutations in either the K-ras or the Epidermal Growth Factor Receptor (EGFR) genes. We observed that K-ras mutant lines displayed a basal vitamin D receptor (VDR)lowCYP24high phenotype, whereas EGFR mutant lines had a VDRhighCYP24low phenotype. A mutation-associated difference in CYP24 expression was also observed in clinical specimens. Specifically, K-ras mutation was associated with a median 4.2-fold increase in CYP24 mRNA expression (p = 4.8 × 10−7) compared to EGFR mutation in a series of 147 primary lung adenocarcinoma cases. Because of their differential basal expression of VDR and CYP24, we hypothesized that NSCLC cells with an EGFR mutation would be more responsive to 1,25(OH)2D3 treatment than those with a K-ras mutation. To test this, we measured the ability of 1,25(OH)2D3 to increase reporter gene activity, induce transcription of endogenous target genes, and suppress colony formation. In each assay, the extent of 1,25(OH)2D3 response was greater in EGFR mutation-positive HCC827 and H1975 cells than in K-ras mutation-positive A549 and 128.88T cells. We subsequently examined the effect of combining 1,25(OH)2D3 with erlotinib, which is used clinically in the treatment of EGFR mutation-positive NSCLC. 1,25(OH)2D3/erlotinib combination resulted in significantly greater growth inhibition than either single agent in both the erlotinib-sensitive HCC827 cell line and the erlotinib-resistant H1975 cell line. These data are the first to suggest that EGFR mutations may

  1. Vitamin D and Related Genes, Race and Prostate Cancer Aggressiveness

    DTIC Science & Technology

    2015-12-29

    vitamin D and genetic polymorphisms act synergistically to affect prostate cancer aggressiveness. We examined these associations among vitamin D...epidemiologic techniques for estimating odds of high aggressive prostate cancer according to vitamin D metabolites, PTH, calcium, phosphorus and genetic ...hypotheses a. Statistical analyses have been performed examining associations between 25(OH)D, 1,25(OH)2D, genetic polymorphisms and prostate cancer

  2. Cord Blood Vitamin D Status Impacts Innate Immune Responses

    PubMed Central

    Zhang, Xiaoran; Rastegar, Ida; Liu, Philip T.; Hollis, Bruce W.; Adams, John S.; Modlin, Robert L.

    2011-01-01

    Objectives: Our objectives were to 1) assess cord blood vitamin D concentrations from healthy term newborns, 2) ascertain whether cord blood vitamin D insufficiency precludes optimal induction of the Toll-like receptor (TLR) antimicrobial pathway in monocytes, and 3) determine whether in vitro supplementation with 25-hydroxyvitamin D3 [25(OH)D3] and/or 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] restores TLR-induced antimicrobial responses. Study Design: Plasma concentrations of 25(OH)D and 1,25(OH)2D were measured from cord blood of 23 newborns. Human monocytes were cultured in cord blood plasma and stimulated with TLR2 and TLR4 ligands, and then antimicrobial gene expression was analyzed using quantitative PCR. Results: Cord blood 25(OH)D and 1,25(OH)2D concentrations were positively correlated to each other (r = 0.78; P <0.0001). Compared with those conditioned in vitamin D-sufficient plasma [25(OH)D > 75 nmol/liter], monocytes cultured in severely vitamin D-deficient plasma [25(OH)D < 30 nmol/liter] exhibited decreased TLR-induced cathelicidin expression (P <0.05). Supplementation in vitro of vitamin D-deficient plasma with 25(OH)D3 increased antimicrobial peptide gene expression. Conclusions: Cord blood vitamin D deficiency, by its effects on TLR-induced antimicrobial production, altered in vitro monocyte responses. The observation that exogenous 25(OH)D3 in vitro recovered TLR-induced antimicrobial responses suggests the need for additional prospective investigations to further delineate the role of vitamin D in the newborn immune response. PMID:21470993

  3. Vitamins

    MedlinePlus

    ... rich in vitamin B? whole grains, such as wheat and oats fish and seafood poultry and meats ... rich in vitamin E? whole grains, such as wheat and oats wheat germ leafy green vegetables vegetable ...

  4. Effects of 25-(OH)D3 on fecal Ca and P excretion, bone mineralization, Ca and P transporter mRNA expression and performance in growing female pigs.

    PubMed

    Regassa, Alemu; Adhikari, Roshan; Nyachoti, Charles M; Kim, Woo Kyun

    2015-01-01

    A study was conducted to examine the effects of 25-hydroxyvitamin D3 (25-(OH)D3) on fecal Ca and P excretion, bone mineralization, performance and the mRNA expression of intestinal transporter genes in growing female pigs. Sixty-day old gilts (n = 24) with an average initial BW of 23.13 ± 1.49 kg were randomly allocated to a control diet (diet 1) containing wheat/corn/soybean meal and 150 IU kg(-1) of Vitamin D3, diet 1 + 50 μg of 25-(OH)D3 kg(-1) (diet 2) and diet 1 + 100 μg of 25-(OH)D3 kg(-1) (diet 3). The pigs were housed in an individual pen and had ad libitum access to feed and water for 42 days, and BWG and feed intake were measured weekly. Measures of bone mineralization and expression of Ca and P transporters mRNA were analyzed using Dual Energy X-Ray Absortiometry (DEXA) and quantitative real-time polymerase chain reaction (qRT-PCR), respectively. Data were analyzed using GLM procedure of the Statistical Analysis System (SAS Institute version 9.2). Fecal Ca and P concentration were significantly reduced (P ≤ 0.05) in pigs fed diets 2 and 3 compared with the control diet. Supplementation of 25-(OH)D3 did not significantly improve bone mineralization, animal performance and intestinal transporters mRNA expression except for SLC34A1, a sodium-dependent phosphate transporter 1. In conclusion, supplementation of 25-(OH)D3 in swine nutrition may not improve animal performance but has the potential to reduce environmental pollution by increasing dietary Ca and P retention while reducing their excretion.

  5. Oral Calcidiol Is More Effective Than Cholecalciferol Supplementation to Reach Adequate 25(OH)D Levels in Patients with Autoimmune Diseases Chronically Treated with Low Doses of Glucocorticoids: A "Real-Life" Study.

    PubMed

    Ortego-Jurado, Miguel; Callejas-Rubio, José-Luis; Ríos-Fernández, Raquel; González-Moreno, Juan; González Ramírez, Amanda Rocío; González-Gay, Miguel A; Ortego-Centeno, Norberto

    2015-01-01

    Glucocorticoids (GCs) are the cornerstone of the therapy in many autoimmune and inflammatory diseases. However, it is well known that their use is a double edged sword, as their beneficial effects are associated almost universally with unwanted effects, as, for example glucocorticoid-induced osteoporosis (GIO). Over the last years, several clinical practice guidelines emphasize the need of preventing bone mass loss and reduce the incidence of fractures associated with GC use. Calcium and vitamin D supplementation, as adjunctive therapy, are included in all the practice guidelines. However, no standard vitamin D dose has been established. Several studies with postmenopausal women show that maintaining the levels above 30-33 ng/mL help improve the response to bisphosphonates. It is unknown if the response is the same in GIO, but in the clinical practice the levels are maintained at around the same values. In this study we demonstrate that patients with autoimmune diseases, undergoing glucocorticoid therapy, often present suboptimal 25(OH)D levels. Patients with higher body mass index and those receiving higher doses of glucocorticoids are at increased risk of having lower levels of 25(OH)D. In these patients, calcidiol supplementations are more effective than cholecalciferol to reach adequate 25(OH)D levels.

  6. Oral Calcidiol Is More Effective Than Cholecalciferol Supplementation to Reach Adequate 25(OH)D Levels in Patients with Autoimmune Diseases Chronically Treated with Low Doses of Glucocorticoids: A “Real-Life” Study

    PubMed Central

    Ortego-Jurado, Miguel; Callejas-Rubio, José-Luis; Ríos-Fernández, Raquel; González-Moreno, Juan; González Ramírez, Amanda Rocío; González-Gay, Miguel A.; Ortego-Centeno, Norberto

    2015-01-01

    Glucocorticoids (GCs) are the cornerstone of the therapy in many autoimmune and inflammatory diseases. However, it is well known that their use is a double edged sword, as their beneficial effects are associated almost universally with unwanted effects, as, for example glucocorticoid-induced osteoporosis (GIO). Over the last years, several clinical practice guidelines emphasize the need of preventing bone mass loss and reduce the incidence of fractures associated with GC use. Calcium and vitamin D supplementation, as adjunctive therapy, are included in all the practice guidelines. However, no standard vitamin D dose has been established. Several studies with postmenopausal women show that maintaining the levels above 30–33 ng/mL help improve the response to bisphosphonates. It is unknown if the response is the same in GIO, but in the clinical practice the levels are maintained at around the same values. In this study we demonstrate that patients with autoimmune diseases, undergoing glucocorticoid therapy, often present suboptimal 25(OH)D levels. Patients with higher body mass index and those receiving higher doses of glucocorticoids are at increased risk of having lower levels of 25(OH)D. In these patients, calcidiol supplementations are more effective than cholecalciferol to reach adequate 25(OH)D levels. PMID:26124976

  7. Single high-dose vitamin D at birth corrects vitamin D deficiency in infants in Mexico.

    PubMed

    Moodley, Amaran; Spector, Stephen A

    2015-05-01

    This study examined the prevalence of vitamin D deficiency in mothers and infants in Tijuana, Mexico and determined the effect of a single oral dose of 50,000 IU vitamin D3 at birth on 25-hydroxyvitamin D (25[OH]D) levels during infancy. Healthy infants were randomized to receive vitamin D3 or placebo at birth. At birth 23% of infants were vitamin D deficient and 77% had vitamin D insufficiency (mean 25[OH]D level 18.9 ng/ml); 10% of mothers were vitamin D deficient and 61% were insufficient. Infants receiving vitamin D3 had higher 25(OH)D levels at two months (N = 29; 33.9 versus 24.2 ng/ml) and six months (N = 21; 36.5 versus 27.4 ng/ml). Exclusively breastfed infants had lower 25(OH)D levels at two months (14.9 versus 33.4 ng/ml). Vitamin D deficiency is common in infants and mothers in Tijuana, Mexico. A single dose of vitamin D3 at birth was safe and significantly increased 25(OH)D levels during infancy.

  8. Vitamin D Status of College Students: Implications for Health Leaders

    ERIC Educational Resources Information Center

    Cress, Eileen McKenna

    2014-01-01

    Vitamin D deficiency is considered to be a pandemic with implications for compromised bone health and other chronic diseases. Few studies have examined vitamin D status in college-aged individuals where prevention of future health consequences is still possible. Serum vitamin D 25(OH)D status and vitamin D intake were examined in 98 college…

  9. Regulation of expression of 1,25D3-MARRS/ERp57/PDIA3 in rat IEC-6 cells by TGF beta and 1,25(OH)2D3.

    PubMed

    Rohe, Benjamin; Safford, Susan E; Nemere, Ilka; Farach-Carson, Mary C

    2007-02-01

    We examined the transcriptional regulation of expression of the redox-sensitive Membrane-Associated-Rapid Response, Steroid-binding (1,25D(3)-MARRS) protein specific for 1,25(OH)(2)D(3) in a rat small intestinal cell line, IEC-6, that demonstrates rapid responses to 1,25(OH)(2)D(3). 1,25D(3)-MARRS binds and is activated by 1,25(OH)(2)D(3), but is not itself up-regulated by treatment with 1,25(OH)(2)D(3), nor is there a Vitamin D response element (VDRE) in its proximal promoter. We previously reported that transforming growth factor beta (TGFbeta) increased steady state levels of 1,25D(3)-MARRS transcript and protein approximately two-fold [Rohe B, Safford SE, Nemere I, Farach-Carson, MC. Identification and characterization of 1,25D(3)-membrane-associated rapid response, steroid (1,25D(3)-MARRS)-binding protein in rat IEC-6 cells. Steroids 2005;70:458-63]. To determine if this up-regulation could be attributed to the function of a highly conserved consensus smad 3 binding element present in the proximal promoter of the 1,25D(3)-MARRS gene, we created a promoter-reporter [SEAP] construct that was responsive to TGFbeta (200 pM). Deletion or mutation of the smad 3 element greatly reduced the response of the 1,25D(3)-MARRS promoter to TGFbeta. Subsequent studies found that the smad 3 response element is bound by a protein found in the IEC-6 nuclear extract, most likely smad 3. Interestingly, although 1,25(OH)(2)D(3) alone did not increase expression of the 1,25D(3)-MARRS promoter-reporter, co-treatment of transfected IEC-6 cells with 1,25(OH)(2)D(3) and TGFbeta shifted the dose-response curve to a lower effective concentration (100 pM peptide). We conclude that TGFbeta is a transcriptional regulator of 1,25D(3)-MARRS expression via a functional smad 3 element and that cross-talk with non-classical 1,25(OH)(2)D(3)-stimulated pathways occurs. The findings have broad implications for redox-sensitive signaling phenomena including those that regulate phosphate transport in

  10. Association between vitamin D metabolites in fat tissue and serum 25-hydroxy vitamin D in overweight and obese adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cholecalciferol has been measured in human white adipose tissue (WAT), but little is known about the relationship between the other circulating vitamin D metabolites and WAT. We measured concentrations of 25(OH)D and 1,25(OH)2D in subcutaneous fat tissue from 20 overweight and obese subjects partic...

  11. Effects of ethnicity and vitamin D supplementation on vitamin D status and changes in bone mineral content in infants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To evaluate the effects on serum 25(OH)D and bone mineralization of supplementation of breast-fed Hispanic and non-Hispanic Caucasian infants with vitamin D in infants in Houston, Texas. We measured cord serum 25(OH)D levels, bone mineral content (BMC), bone mineral density (BMD) and their changes o...

  12. Serum vitamin D, vitamin D binding protein, and lung cancer survival

    PubMed Central

    Anic, Gabriella M.; Weinstein, Stephanie J.; Mondul, Alison M.; Männistö, Satu; Albanes, Demetrius

    2014-01-01

    Objectives Vitamin D may prolong cancer survival by inhibiting tumor progression and metastasis, however, there are limited epidemiologic studies regarding the association between circulating 25-hydroxyvitamin D (25(OH)D) and lung cancer survival. The aim of this study was to examine the relationship between serum 25(OH)D and lung cancer specific survival and to evaluate whether vitamin D binding protein (DBP) concentration modified this association. Materials and Methods 25(OH)D and DBP were measured in fasting serum samples from 500 male lung cancer cases in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study. Cox proportional hazards regression was used to estimate hazard ratios (HRs) and 95% confidence intervals (CI) for lung cancer related death according to quartiles of season-specific 25(OH)D, DBP, and the molar ratio of 25(OH)D:DBP, a proxy for free circulating 25(OH)D. Results Comparing highest to lowest quartiles, serum 25(OH)D (HR=1.18; 95% CI: 0.89–1.56) and DBP (HR=0.95; 95% CI: 0.71–1.26) were not associated with lung cancer survival and DBP concentration did not modify the association with 25(OH)D (p for interaction=0.56). There was suggestion of an association between higher serum 25(OH)D and better survival from adenocarcinoma (HR=0.64; 95% CI: 0.17–2.45) and small cell carcinoma (HR=0.55; 95% CI: 0.21–1.45), but these estimates were based on a relatively small number of cases. Conclusion Serum 25(OH)D was not associated with overall lung cancer survival regardless of DBP concentration, however, these findings should be examined in other studies that include women and subjects with higher 25(OH)D levels. PMID:25456734

  13. Effects of vitamin D3 supplementation and UVb exposure on the growth and plasma concentration of vitamin D3 metabolites in juvenile bearded dragons (Pogona vitticeps).

    PubMed

    Oonincx, D G A B; Stevens, Y; van den Borne, J J G C; van Leeuwen, J P T M; Hendriks, W H

    2010-06-01

    The effectiveness of dietary vitamin D3 and UVb exposure on plasma vitamin D metabolites in growing bearded dragons (Pogona vitticeps) was studied. A total of 84 (40 males and 44 females) newly hatched bearded dragons were allocated to six levels of oral vitamin D3 supplementation (0 to 400%) or six UVb exposure times (2 to 12 h). At 3 and 6 months of age, blood samples were obtained from each animal and analysed for 25(OH)D3 and 1,25(OH)2D3. At 3 months of age, plasma concentrations of 25(OH)D3 did not increase with increasing vitamin D3 supplementation unlike the 1,25(OH)2D3. At 6 months of age, plasma concentrations of both 25(OH)D(3) and 1,25(OH)2D3 increased with increasing vitamin D(3) supplementation. Plasma concentrations in UVb-exposed animals were 18 times higher for 25(OH)D3 (178.4+/-9.0 vs. 9.9+/-1.3 nmol/L) and 5.3 times higher for 1,25(OH)2D3 (1.205+/-0.100 vs. 0.229+/-0.025 nmol/L) than in vitamin D(3) supplemented animals at 6 months of age. This study shows that 2h of UVb exposure enables adequate physiological concentrations of plasma vitamin D metabolites to be maintained in growing bearded dragons. Oral supplementation of vitamin D(3) is ineffective in raising plasma concentrations of 25(OH)D3 and 1,25(OH)2D3 to concentrations observed in UVb-exposed animals.

  14. Vitamin D: A millenium perspective.

    PubMed

    Holick, Michael F

    2003-02-01

    Vitamin D is one of the oldest hormones that have been made in the earliest life forms for over 750 million years. Phytoplankton, zooplankton, and most plants and animals that are exposed to sunlight have the capacity to make vitamin D. Vitamin D is critically important for the development, growth, and maintenance of a healthy skeleton from birth until death. The major function of vitamin D is to maintain calcium homeostasis. It accomplishes this by increasing the efficiency of the intestine to absorb dietary calcium. When there is inadequate calcium in the diet to satisfy the body's calcium requirement, vitamin D communicates to the osteoblasts that signal osteoclast precursors to mature and dissolve the calcium stored in the bone. Vitamin D is metabolized in the liver and then in the kidney to 1,25-dihydroxyvitamin D [1,25(OH)(2)D]. 1,25(OH)(2)D receptors (VDR) are present not only in the intestine and bone, but in a wide variety of other tissues, including the brain, heart, stomach, pancreas, activated T and B lymphocytes, skin, gonads, etc. 1,25(OH)(2)D is one of the most potent substances to inhibit proliferation of both normal and hyperproliferative cells and induce them to mature. It is also recognized that a wide variety of tissues, including colon, prostate, breast, and skin have the enzymatic machinery to produce 1,25(OH)(2)D. 1,25(OH)(2)D and its analogs have been developed for treating the hyperproliferative disease psoriasis. Vitamin D deficiency is a major unrecognized health problem. Not only does it cause rickets in children, osteomalacia and osteoporosis in adults, but may have long lasting effects. Chronic vitamin D deficiency may have serious adverse consequences, including increased risk of hypertension, multiple sclerosis, cancers of the colon, prostate, breast, and ovary, and type 1 diabetes. There needs to be a better appreciation of the importance of vitamin D for overall health and well being.

  15. Vitamins

    MedlinePlus

    ... wheat and oats wheat germ leafy green vegetables vegetable oils like sunflower, canola, and olive egg yolks nuts ... foods are rich in vitamin K? leafy green vegetables dairy products, like milk and yogurt broccoli soybean oil When your body gets this vitamin and the ...

  16. The effects of vitamin D2 or D3 supplementation on glycaemic control and related metabolic parameters in people at risk of type 2 diabetes: protocol of a randomised double-blind placebo-controlled trial

    PubMed Central

    2013-01-01

    Background The global prevalence of type 2 diabetes is increasing. Effective strategies to address this public health challenge are currently lacking. A number of epidemiological studies have reported associations between low concentrations of 25-hydroxy vitamin D and the incidence of diabetes, but a causal link has not been established. We investigate the effect of vitamin D supplementation on the metabolic status of individuals at increased risk of developing type 2 diabetes. Methods/design In a randomised double-blind placebo-controlled trial individuals identified as having a high risk of type 2 diabetes (non-diabetic hyperglycaemia or positive diabetes risk score) are randomised into one of three groups and given 4 doses of either placebo, or 100,000 IU Vitamin D2 (ergocalciferol) or 100,000 IU Vitamin D3 (cholecalciferol) at monthly intervals. The primary outcome measure is the change in glycated haemoglobin level between baseline and 4 months. Secondary outcome measures include blood pressure, lipid levels, apolipoproteins, highly sensitive C-reactive protein, parathyroid hormone (PTH) and safety of supplementation. and C-reactive protein. The trial is being conducted at two sites (London and Cambridge, U.K.) and a total of 342 participants are being recruited. Discussion Trial data examining whether supplementation of vitamin D improves glycaemic status and other metabolic parameters in people at risk of developing type 2 diabetes are sparse. This trial will evaluate the causal role of vitamin D in hyperglycaemia and risk of type 2 diabetes. Specific features of this trial include recruitment of participants from different ethnic groups, investigation of the relative effectiveness and safety of vitamin D2 and D3 and an evidence based approach to determination of the dose of supplementation. Trial registration EudraCT2009-011264-11; ISRCTN86515510 PMID:24152375

  17. [Vitamin D, determinant of bone and extrabone health. Importance of vitamin D supplementation in milk and dairy products].

    PubMed

    Navarro Valverde, Cristina; Quesada Gómez, José Manuel

    2015-04-07

    Vitamin D is obtained mainly from ultraviolet irradiation of 7-dehydrocholesterol in the skin to form cholecalciferol (vitamin D3), and minimally from diet, unless vitamin D fortified food is taken, mainly enriched milk. In some countries, vitamin D is added to diet as ergocalciferol (vitamin D2). In the liver, vitamin D3 is hydroxylated to form 25-hydroxyvitamin D3 (marker of body nutritional status of vitamin D). Subsequently, in the kidney, 25OHD3 is hydroxylated to form 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). By VDR stimulation, (1,25)OH)2D3 controls calcium homeostasis and bone health and, what is more, many other cells and tissues including skin, muscle, cardiovascular and immune systems as well as glucose homeostasis. Thus, about 3% of the human genome is regulated by this hormone. Association and recent intervention studies describe beneficial effects on bone, cardiovascular disease, hypertension, diabetes mellitus type 2,colorectal cancer, breast cancer, multiple sclerosis, immune function inflammation etc. A minimum target for public health should be to achieve serum 25OHD levels above 20 ng/ml to ensure optimum status for bone health. However, levels above 30 ng/ml should be reached to achieve other health goals. Paradoxically, inadequacy (or even deficiency) in vitamin D levels is highly prevalent in children and youth in Spain. This deficit persists in adults, as well as in postmenopausal women (osteoporotic or not) and the elderly (especially amongst those institutionalized). Seasonal variation barely normalizes serum 25OHD levels after summer-autumn. Treated postmenopausal osteoporotic women also show high prevalence of inadequate levels of vitamin D, a major contributor to antiresortive treatments failure. A normalization of serum vitamin D enables diet to provide the calcium necessary to achieve a good bone health and an adequate response to antiresortive drugs. Given the difficulty to get adequate levels of vitamin D by UV irradiation and diet, a

  18. Determination of serum 25-hydroxy cholecalciferol using high-performance liquid chromatography: a reliable tool for assessment of vitamin D status.

    PubMed

    Neyestani, Tirang R; Gharavi, A'azam; Kalayi, Ali

    2007-09-01

    This study was undertaken to design and set up a rather simple, reliable, and less expensive high-performance liquid chromatography (HPLC)-based method to assay 25(OH)D as a diagnostic tool for vitamin D assessment. Serum proteins were precipitated using ethanol and, after 10 minutes incubation at room temperature, methanol:isopropanol. The extraction was performed using hexane followed by evaporation under nitrogen flow. The sediment was then reconstituted in methanol and passed through a polypropylene filter. To run the chromatographic analysis, 20 microL of the filtrate was injected to the column. Peaks of 25(OH)D2 and 25(OH)D3 were both detected using a UV detector set at 265 nm. With a flow rate of 1.2 mL/minute, peaks of D3 and D2 vitamers were detected around 9.5 and 10.7 minutes, respectively. The intra- and inter-assay variations were 8.1% and 12.6%, respectively, and the recovery percent was found to be 100 +/- 5%. To compare the procedure with conventional methods, 90 serum samples from subjects (48 females and 42 males) aged 40.5 +/- 13.9 yrs, were analyzed for 25(OH)D using HPLC, competitive protein-binding assay (CPBA), and radioimmunoassay (RIA). Generally, CPBA and RIA assays both showed over-estimation of serum 25(OH)D, compared to HPLC. Though all three methods correlated significantly with each other, with the strongest between HPLC and RIA (r = 0.87, p < 0.001), both RIA and CPBA were found unreliable in detection of some deficient samples.

  19. Vitamin D, Insulin Secretion, Sensitivity, and Lipids

    PubMed Central

    Grimnes, Guri; Figenschau, Yngve; Almås, Bjørg; Jorde, Rolf

    2011-01-01

    OBJECTIVE Vitamin D deficiency is associated with an unfavorable metabolic profile in observational studies. The intention was to compare insulin sensitivity (the primary end point) and secretion and lipids in subjects with low and high serum 25(OH)D (25-hydroxyvitamin D) levels and to assess the effect of vitamin D supplementation on the same outcomes among the participants with low serum 25(OH)D levels. RESEARCH DESIGN AND METHODS Participants were recruited from a population-based study (the Tromsø Study) based on their serum 25(OH)D measurements. A 3-h hyperglycemic clamp was performed, and the participants with low serum 25(OH)D levels were thereafter randomized to receive capsules of 20,000 IU vitamin D3 or identical-looking placebo twice weekly for 6 months. A final hyperglycemic clamp was then performed. RESULTS The 52 participants with high serum 25(OH)D levels (85.6 ± 13.5 nmol/L [mean ± SD]) had significantly higher insulin sensitivity index (ISI) and lower HbA1c and triglycerides (TGs) than the 108 participants with low serum 25(OH)D (40.3 ± 12.8 nmol/L), but the differences in ISI and TGs were not significant after adjustments. After supplementation, serum 25(OH)D was 142.7 ± 25.7 and 42.9 ± 17.3 nmol/L in 49 of 51 completing participants randomized to vitamin D and 45 of 53 randomized to placebo, respectively. At the end of the study, there were no statistically significant differences in the outcome variables between the two groups. CONCLUSIONS Vitamin D supplementation to apparently healthy subjects with insufficient serum 25(OH)D levels does not improve insulin sensitivity or secretion or serum lipid profile. PMID:21911741

  20. Effect of adiposity, season, diet and calcium or vitamin D supplementation on the vitamin D status of healthy urban African and Asian-Indian adults.

    PubMed

    George, Jaya A; Norris, Shane A; van Deventer, Hendrick E; Pettifor, John M; Crowther, Nigel J

    2014-08-28

    Vitamin D deficiency has been implicated in the aetiology of infectious diseases and metabolic syndrome. These diseases are prevalent in the African and Asian-Indian populations of South Africa; however, there is limited data on 25-hydroxyvitamin D (25(OH)D) concentrations in these populations. The aim of the present study was to assess the vitamin D status and its predictors in healthy adults in Johannesburg. We assessed the vitamin D status of 730 adult African and Asian-Indian subjects residing in Johannesburg. The contributions of sun exposure, season, dietary intake of Ca and vitamin D, total body fat and body fat distribution to 25(OH)D concentrations were assessed. The concentrations of 25(OH)D were measured by HPLC. The contribution of 25(OH)D₃ to total 25(OH)D concentrations was assessed. The mean age of the subjects was 42·6 (SD 13·1) years (range: 18-65). Concentrations of 25(OH)D < 30 nmol/l were found in 28·6 % of the Asian-Indian subjects in comparison with 5·1 % of the African subjects (P< 0·0001). Parathyroid hormone (PTH) concentrations were negatively associated with 25(OH)D concentrations, while season and sun exposure were positive predictors explaining 16 % of the variance in 25(OH)D concentrations (P< 0·0001) in the African subjects. In the Asian-Indian subjects, PTH concentrations were negatively associated with 25(OH)D concentrations, while male sex, season and Ca supplementation were positive predictors and explained 17 % of the variance in 25(OH)D concentrations (P< 0·0001). In the multivariate regression analysis, neither total body fat nor body fat distribution was predictive of 25(OH)D concentrations in either group. In conclusion, factors such as sun exposure, dietary supplement use and ethnicity are important determinants of plasma 25(OH)D concentrations.

  1. [Recent advances on vitamin D (author's transl)].

    PubMed

    Monnier, L; Colette, C; Mirouze, J

    1980-06-01

    Our knowledge of vitamin D metabolism has undergone major advances within the last few years. The vitamin D3 produced by the skin or absorbed across the intestine is converted successively to 25-hydroxyvitamin D3 by the liver and to 1,25-hydroxyvitamin D3 (1,25-(OH)2D3) by the kidney. The latter metabolite is also the most active on three types of target tissue: gut, bone and kidney. The mechanism of action of 1,25-(OH2D3 has been investigated mostly in the intestinal tract, where it increased calcium absorption by stimulating the synthesis of such transfer proteins as the calcium binding protein (Ca BP). Although the level of 1,25 (OH)2D3 is regulated by vitamin D intake, it depends mainly on renal hydroxylation, the limiting step which controls 1,25-(OH)2D3 production. Both parathyroid hormone and calcium or phosphorus depletion stimulate renal 1-alpha-hydroxylase; 1,25-(OH)2D3 is also regulated directly or indirectly (through its action on the parathyroid glands) by a feedback system. In some diseases such as hepatic insufficiency and chronic renal failure, a profound impairment in endogenous synthesis of the biologically active metabolites of vitamin D results in sever calcium and skeletal disese. During the last decade, the therapeutic possibilities in vitamin D deficiency have been greatly improved by the synthesis of new derivatives of vitamin D and by a better knowledge of their bioavailability

  2. 25-Hydroxyvitamin D Concentration, Vitamin D Intake and Joint Symptoms in Postmenopausal Women

    PubMed Central

    Chlebowski, Rowan T.; Johnson, Karen C.; Lane, Dorothy; Pettinger, Mary; Kooperberg, Charles L.; Wactawski-Wende, Jean; Rohan, Tom; Jo O'Sullivan, Mary; Yasmeen, Shagufta; Hiatt, Robert A.; Shikany, James M.; Vitolins, Mara; Khandekar, Janu; Hubbell, F. Allan

    2010-01-01

    Introduction Low 25 hydroxyvitamin D (25(OH) D) concentrations have been associated with radiologic worsening of osteoarthritis in some reports. However, the results are mixed and few studies have evaluated associations between 25(OH) D concentrations and both total vitamin D intake and clinical joint symptoms. Study Design Cross-sectional analyses of information from a subset of 1993 postmenopausal women obtained at baseline entry in the Women's Health Initiative Calcium plus Vitamin D clinical trial. Main Outcome Measures 25(OH) D concentration, total vitamin D intake (diet plus supplements), presence and severity of joint pain and joint swelling. Results The 25(OH) D levels were commonly low with 53% having deficient (< 50 nmol/L) and only 17% having sufficient (> 72 nmol/L) levels. Joint pain (reported by 74%) and joint swelling (reported by 34%) were also commonly reported. 25(OH) D concentrations were modestly correlated with total vitamin D intake (R =0.29, P<0.0001); however, considerable variability in 25(OH) D concentrations for a given vitamin D intake was seen. In adjusted linear regression models, lower serum 25(OH) D concentrations were associated with higher average joint pain score (P=0.01 for trend) with differences most apparent in the lowest 25(OH) D levels sextile. Conclusions Relatively low 25(OH) D levels and a high frequency of joint symptoms were common in this population of postmenopausal women. Total vitamin D intake was only modestly associated with 25(OH) D. Low serum 25(OH) D concentrations were associated with higher joint pain scores. These findings can inform the design of future intervention trials. PMID:21093181

  3. The First Intervention Study in Elder Self-Neglect: A Randomized Clinical Trial to Improve Vitamin D Levels

    NASA Technical Reports Server (NTRS)

    Burnett, Jason; Hochschild, Ann; Smith, Scott M.; Diamond, Pam; Stotts, Angela; Dyer, Carmel

    2011-01-01

    Despite high mortality rates, elder self-neglect is characterized by refusal of medical and social interventions. To date there have been no tested clinical interventions in elders who self-neglect. Previous research from the TEAM Institute has shown significantly low vitamin D levels in this population. This study aimed to determine the feasibility of a clinical intervention. Replacement of vitamin D was chosen because of its ease of administration and favorable safety profile. Methods: A randomized clinical trial using directly observed therapy of vitamin D was conducted using 50 elders, >65 years of age, with Adult Protective Services (APS) validated self-neglect. A staggered intervention with waiting controls was used to maximize statistical power. One-third (n=17) of the group was administered 50,000 IU vitamin D2 (ergocalciferol) monthly and the remainder (n=33) were administered 400 IU monthly. Serum 25-OH vitamin D was assessed at baseline and 5-months. Results: 69% agreed to participate in the study and of those n=40 (80%) remained at 5-months. At baseline, 12% (n=7) were deficient in vitamin D (<30nmol/L) and approximately 38% (n=22) had inadequate vitamin D levels (<50nmol/L). The baseline 25-OH vitamin D level was 59 nmol/L +25 (mean SD), and increased significantly to 72nmol/L +21 nmol/L at 5-months. Conclusion: These data are the first to provide evidence that clinical interventions are feasible in elders who self-neglect. The increase in vitamin D levels confirmed that the study personnel were able to successfully intervene community-dwelling elders with self-neglect. This study sets the precedent for future intervention and prevention studies

  4. Vitamin D and ultraviolet phototherapy in Caucasians.

    PubMed

    Grigalavicius, Mantas; Moan, Johan; Dahlback, Arne; Juzeniene, Asta

    2015-06-01

    Ultraviolet B (UVB) radiation increases vitamin D level, but the influence of different UV sources (broadband and narrowband UVB lamps, solar simulators and sunbeds) and exposure durations have not been well characterized. In this study the influence of different UV sources on serum 25-hydroxyvitamin-D3 (25(OH)D3) levels in humans are reviewed. Serum 25(OH)D levels before and after UV exposure, and UV doses were extracted from 18 papers published in the past eight years. It was found that the UV dose-response curve for vitamin D generation in humans, as measured by the increments of serum 25(OH)D, is not linear with increasing UV doses and reaches a plateau at about 55 nmol/L after 4-5 weeks. About a half of this increase is equal to the difference between winter and summer 25(OH)D levels, and may be reached after 23 SEDs. The increments decrease with increasing baseline concentration of serum 25(OH)D, and the efficiency of only 0.7 nmol/L per SED is expected on the average when initial concentrations are higher than 50-60 nmol/L. A whole body exposure to 2 SEDs of UVB radiation 3 times per week is expected to rise serum 25(OH)D with an initial rate of 3.9 nmol/L per SED, bringing a winter level of serum 25(OH)D up to a summer level.

  5. Toward an Inexpensive Test for Vitamin D Levels in Blood

    DTIC Science & Technology

    2014-12-01

    enhance the direct electron transfer between electrode and redox center of CYP27B1. This is important for introducing a way to electrochemically measure...vitamin D, 25(OH)D, electrochemical biosensors. 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF...detection. 2. Keywords Cytochrome P450, mediated electrochemistry, direct electron chemistry, vitamin D, 25(OH)D, electrochemical biosensors. 3

  6. Vitamins

    MedlinePlus

    ... nutrients include: Proteins Carbohydrates Fats Vitamins Minerals Water Proteins Proteins are an important part of your bones, muscles, and skin. In fact, proteins are in every living cell in your body. ...

  7. Clinical Utility of Measurement of Vitamin D-Binding Protein and Calculation of Bioavailable Vitamin D in Assessment of Vitamin D Status

    PubMed Central

    Kim, Hyun-Jeong; Ji, Misuk; Song, Junghan; Moon, Hee-Won; Hur, Mina

    2017-01-01

    Background The associations of vitamin D deficiency with various clinical conditions highlighted the importance of vitamin D testing. Currently, clinicians measure only the total 25-hydroxyvitamin D [25(OH)D] concentration, regardless of its bioavailability. We aimed to determine the effect of vitamin D-binding protein (VDBP) on 25(OH)D bioavailability. Methods Serum samples were collected from 60 healthy controls, 50 pregnant women, and 50 patients in intensive care units (ICUs). Total 25(OH)D was quantified by liquid chromatography with tandem mass spectrometry, and VDBP levels were determined by using an ELISA kit (R&D Systems, USA). The bioavailable 25(OH)D levels were calculated by using total 25(OH)D, VDBP, and albumin concentrations. Results In comparison with healthy controls, the total 25(OH)D concentration was significantly lower in ICU patients (median, 11.65 vs 18.25 ng/mL; P<0.00001), but no significant difference was noted between pregnant women (18.25 ng/mL) and healthy controls. The VDBP level was significantly lower in ICU patients (95.58 vs 167.18 µg/mL, P=0.0002) and higher in pregnant women (225.01 vs 167.18 µg/mL, P=0.008) compared with healthy controls. Nonetheless, the calculated bioavailable 25(OH)D levels of ICU patients and pregnant women were significantly lower than those of healthy controls (1.97 and 1.93 ng/mL vs 2.56 ng/mL; P=0.0073 and 0.0027). Conclusions A single marker of the total 25(OH)D level is not sufficient to accurately evaluate vitamin D status, especially in pregnant women. In cases where VDBP concentrations may be altered, VDBP measurements and bioavailable 25(OH)D calculations may help to determine vitamin D status accurately. PMID:27834063

  8. Enhancement of antioxidant properties and increase of content of vitamin D2 and non-volatile components in fresh button mushroom, Agaricus bisporus (higher Basidiomycetes) by γ-irradiation.

    PubMed

    Tsai, Shu-Yao; Mau, Jeng-Leun; Huang, Shih-Jeng

    2014-01-01

    Agaricus bisporus is a popular culinary-medicinal mushroom in Taiwan, and γ-irradiation could extend its shelf life. Our objective was to study the content of vitamin D2 and the taste components and antioxidant properties of ethanolic extracts from A. bisporus with various doses of γ-irradiation. After irradiation, the vitamin D2 content of 5-10 kGy irradiated mushrooms was in the range of 5.22-7.90 µg/g, higher than that of the unirradiated control (2.24 µg/g). For all treatments, the total content of soluble sugars and polyols ranged from 113 to 142 mg/g, and the monosodium glutamate-like components ranged from 6.57 to 13.50 mg/g, among which the 2.5 kGy irradiated sample has the highest content of flavor 5'-nucleotide. About antioxidant properties, 10 kGy irradiated samples exhibited lower EC50 values than did other samples. EC50 values were less than 5 mg/mL for ethanolic extracts. Total phenols were the major antioxidant components and the total content was 13.24-22.78 mg gallic acid equivalents/g. Based on the results obtained, γ-irradiation could be used to improve the vitamin D2 content and intensity of umami taste in fresh mushrooms. In addition, γ-irradiation not only maintained the antioxidant properties of mushrooms but also enhanced the antioxidant properties to some extent.

  9. Vitamin D Supplementation in Submariners

    DTIC Science & Technology

    2008-12-02

    vitamin D3 (vit D3 ) or pre- vitamin D2 (vit D2 ) that are both acquired from the environment, but has...skin) (From Diet) Vitamin D3 (Cholecalciferol) UV light Vitamin D2 (Ergocalciferol) Liver 25-Hydroxy Vitamin D (Calcidiol) Kidney 1,25-Dihydroxy...Gallagher JC, Haynatzki G. Effect of vitamins D2 and D3 supplement use on serum 25OHD concentration in elderly women in summer and winter.

  10. Maternal Obesity and Vitamin D Sufficiency Are Associated with Cord Blood Vitamin D Insufficiency

    PubMed Central

    Feinglass, Joseph; Rademaker, Alfred W.; Metzger, Boyd E.; Zeiss, Dinah M.; Price, Heather E.; Langman, Craig B.

    2013-01-01

    Context: An inverse relationship between total serum 25-hydroxyvitamin D (25-OH D) and increased adiposity has been established in children, adolescents, and adults. However, the relationship between neonatal adiposity and vitamin D status has not been reported. Both maternal obesity and vitamin D deficiency in pregnancy are common and are associated with adverse pregnancy outcomes. Objective: The aim of the study was to determine the relationship between vitamin D levels in mothers and newborns, as influenced by maternal obesity, and evaluate these associations with neonatal adiposity. Design, Setting, and Patients: Sixty-one maternal-neonatal pairs participated in this cross-sectional study at an academic medical center. Mothers had a prepregnancy body mass index that was normal or obese. Outcome Measures: Maternal and cord blood sera were assayed for 25-OH D, and neonatal body composition was measured by air displacement plethysmography. Results: Mothers had similar and sufficient levels of 25-OH D when measured at 36–38 wk gestation, irrespective of body mass index category (normal weight, 46.05, vs. obese, 49.84 ng/ml; P = not significant). However, cord blood 25-OH D was higher in neonates of normal-weight mothers compared to neonates of obese mothers (27.45 vs. 20.81 ng/ml; P = 0.02). The variance in cord blood 25-OH D was explained by four factors: maternal 25-OH D level, the presence of maternal obesity, maternal age, and neonatal adiposity (r2 = 0.66). Conclusion: Obese women transfer less 25-OH D to offspring than normal-weight women, despite similar serum levels. Cord blood 25-OH D levels directly correlate to neonatal percentage body fat. These novel findings underscore the evolving relationships between maternal obesity, vitamin D nutritional status, and adiposity in the neonatal period that may influence subsequent childhood and adulthood vitamin D-dependent processes. PMID:23144468

  11. Low Prevalence of Vitamin D Insufficiency among Nepalese Infants Despite High Prevalence of Vitamin D Insufficiency among Their Mothers

    PubMed Central

    Haugen, Johanne; Ulak, Manjeswori; Chandyo, Ram K.; Henjum, Sigrun; Thorne-Lyman, Andrew L.; Ueland, Per Magne; Midtun, Øivind; Shrestha, Prakash S.; Strand, Tor A.

    2016-01-01

    Background: Describing vitamin D status and its predictors in various populations is important in order to target public health measures. Objectives: To describe the status and predictors of vitamin D status in healthy Nepalese mothers and infants. Methods: 500 randomly selected Nepalese mother and infant pairs were included in a cross-sectional study. Plasma 25(OH)D concentrations were measured by LC-MS/MS and multiple linear regression analyses were used to identify predictors of vitamin D status. Results: Among the infants, the prevalence of vitamin D insufficiency (25(OH)D <50 nmol/L) and deficiency (<30 nmol/L) were 3.6% and 0.6%, respectively, in contrast to 59.8% and 14.0% among their mothers. Infant 25(OH)D concentrations were negatively associated with infant age and positively associated with maternal vitamin D status and body mass index (BMI), explaining 22% of the variability in 25(OH)D concentration. Global solar radiation, maternal age and BMI predicted maternal 25(OH)D concentration, explaining 9.7% of its variability. Conclusion: Age and maternal vitamin D status are the main predictors of vitamin D status in infants in Bhaktapur, Nepal, who have adequate vitamin D status despite poor vitamin D status in their mothers. PMID:28009810

  12. 1,25(OH)2D3 and VDR Signaling Pathways Regulate the Inhibition of Dectin-1 Caused by Cyclosporine A in Response to Aspergillus Fumigatus in Human Corneal Epithelial Cells

    PubMed Central

    Xia, Yiping; Zhao, Guiqiu; Lin, Jing; Li, Cui; Cong, Lin; Jiang, Nan; Xu, Qiang; Wang, Qian

    2016-01-01

    Background The objective of this study is to observe whether cyclosporine A (CsA) inhibits the expression of dectin-1 in human corneal epithelial cells infected with Aspergillus fumigatus (A. fumigatus) and to investigate the molecular mechanisms of the inhibition. Methods Immortalized human corneal epithelial cells (HCECs) were pretreated with 1,25(OH)2D3 and VDR inhibitor for 1 h, and then they were pretreated with CsA for 12h. After these pretreatments, the HCECs were stimulated with A. fumigatus and curdlan respectively, and the expression of dectin-1 and proinflammatory cytokines (IL-1β and TNF-α) were detected by RT-PCR, western blot and ELISA. Results Dectin-1 mRNA and dectin-1 protein expression increased when HCECs were stimulated with A. fumigatus or curdlan, and CsA inhibited the dectin-1 expression both in mRNA and protein levels specifically. Dectin-1 and proinflammatory cytokine expression levels were higher when HCECs were pretreated with VDR inhibitor and CsA compared to pretreatment with CsA alone, while dectin-1 and proinflammatory cytokine levels were lower when HCECs were pretreated with 1,25(OH)2D3 and CsA compared to pretreatment with CsA alone. Conclusions These data provide evidence that CsA can inhibit the expression of dectin-1 and proinflammatory cytokines through dectin-1 when HCECs are stimulated by A. fumigatus or curdlan. The active form of vitamin D, 1,25(OH)2D3, and VDR signaling pathway regulate the inhibition of CsA. The inhibition is enhanced by 1,25(OH)2D3, and the VDR inhibitor suppresses the inhibition. PMID:27755569

  13. Vitamin D-binding protein and free vitamin D concentrations in acromegaly.

    PubMed

    Altinova, Alev Eroglu; Ozkan, Cigdem; Akturk, Mujde; Gulbahar, Ozlem; Yalcin, Muhittin; Cakir, Nuri; Toruner, Fusun Balos

    2016-05-01

    Free 25-hydroxyvitamin D [25(OH)D] is suggested to be important in the determination of vitamin D deficiency, since vitamin D-binding protein (VDBP) may affect total 25(OH)D levels. There are no data about free 25(OH)D concentrations in acromegaly. We aimed to investigate serum VDBP and total and free 25(OH)D levels in patients with acromegaly in comparison with control subjects. We recruited 54 patients with acromegaly and 32 control subjects who were similar according to age, gender, and body mass index. Serum VDBP levels were found to be increased in patients with acromegaly compared to control subjects [90.35 (72.45-111.10) vs. 69.52 (63.89-80.13) mg/l, p = 0.001]. There was statistically no significant difference in serum total 25(OH)D levels between the patients with acromegaly and control subjects [18.63 (13.35-27.73) vs. 22.51 (19.20-28.96) ng/ml, p = 0.05]. Free 25(OH)D levels were significantly decreased in patients with acromegaly compared to control subjects [14.55 (10.45-21.45) vs. 17.75 (15.30-23.75) pg/ml, p = 0.03]. Free 25(OH)D levels correlated positively with total 25(OH)D (p = 0.0001) and HDL cholesterol (p = 0.04) and negatively with fasting blood glucose (p = 0.04). Our findings indicate that VDBP is increased and free 25(OH)D is decreased in acromegaly, while there is no significant alteration in total 25(OH)D.

  14. 24-Hydroxylase in Cancer: Impact on Vitamin D-based Anticancer Therapeutics

    PubMed Central

    Luo, Wei; Hershberger, Pamela A.; Trump, Donald L.; Johnson, Candace S.

    2013-01-01

    The active vitamin D hormone 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) plays a major role in regulating calcium homeostasis and bone mineralization. 1,25(OH)2D3 also modulates cellular proliferation and differentiation in a variety of cell types. 24-hydroxylase, encoded by the CYP24A1 gene, is the key enzyme which converts 1,25(OH)2D3 to less active calcitroic acid. Nearly all cell types express 24-hydroxylase, the highest activity being observed in the kidney. There is increasing evidence linking the incidence and prognosis of certain cancers to low serum 25 (OH)D3 levels and high expression of vitamin D 24-hydroxylase supporting the idea that elevated CYP24A1 expression may stimulate degradation of vitamin D metabolites including 25-(OH)D3 and 1,25(OH)2D3. The over expression of CYP24A1 in cancer cells may be a factor affecting 1,25(OH)2D3 bioavailability and anti-proliferative activity pre-clinically and clinically. The combination of 1,25(OH)2D3 with CYP24A1 inhibitors enhances 1,25(OH)2D3 mediated signaling and anti-proliferative effects and may be useful in overcoming effects of aberrant CYP24 expression. PMID:23059474

  15. Vitamin D and Actigraphic Sleep Outcomes in Older Community-Dwelling Men: The MrOS Sleep Study

    PubMed Central

    Massa, Jennifer; Stone, Katie L.; Wei, Esther K.; Harrison, Stephanie L.; Barrett-Connor, Elizabeth; Lane, Nancy E.; Paudel, Misti; Redline, Susan; Ancoli-Israel, Sonia; Orwoll, Eric; Schernhammer, Eva

    2015-01-01

    Study Objectives: Maintaining adequate serum levels of vitamin D may be important for sleep duration and quality; however, these associations are not well understood. We examined whether levels of serum 25(OH)D are associated with objective measures of sleep in older men. Setting and Participants: Cross-sectional study within a large cohort of community-dwelling older men, the MrOS study. Interventions: Among 3,048 men age 68 years or older, we measured total serum vitamin D. Objective estimates of nightly total sleep time, sleep efficiency, and wake time after sleep onset (WASO) were obtained using wrist actigraphy worn for an average of 5 consecutive 24-h periods. Results: 16.4% of this study population had low levels of vitamin D (< 20.3 ng/mL 25(OH)D). Lower serum vitamin D levels were associated with a higher odds of short (< 5 h) sleep duration, (odds ratio [OR] for the highest (≥ 40.06 ng/mL) versus lowest (< 20.3 ng/mL) quartile of 25(OH)D, 2.15; 95 % confidence interval (CI), 1.21–3.79; Ptrend = 0.004) as well as increased odds of actigraphy-measured sleep efficiency of less than 70% (OR, 1.45; 95% CI, 0.97–2.18; Ptrend = 0.004), after controlling for age, clinic, season, comorbidities, body mass index, and physical and cognitive function. Lower vitamin D levels were also associated with increased WASO in age-adjusted, but not multivariable adjusted models Conclusions: Among older men, low levels of total serum 25(OH)D are associated with poorer sleep including short sleep duration and lower sleep efficiency. These findings, if confirmed by others, suggest a potential role for vitamin D in maintaining healthy sleep. Citation: Massa J, Stone KL, Wei EK, Harrison SL, Barrett-Connor E, Lane NE, Paudel M, Redline S, Ancoli-Israel S, Orwoll E, Schernhammer E. Vitamin D and actigraphic sleep outcomes in older community-dwelling men: the MrOS Sleep Study. SLEEP 2015;38(2):251–257. PMID:25581929

  16. Vitamin D and Calcium for Fracture Prevention

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Inadequate intakes of vitamin D and calcium lead to reduced calcium absorption, higher bone-remodeling rates and increased bone loss. Vitamin D has also been linked to muscle function and risk of falling. In older men and women, higher 25-hydroxyvitamin D [25(OH)D] levels are associated with bette...

  17. Vitamin D and the digestive system.

    PubMed

    Stumpf, Walter E

    2008-01-01

    Target tissues of in vivo receptor binding and deposition of 1,25(OH)2 vitamin D3 and its oxygen analog OCT are reviewed in rats, mice, hamsters and zebra finch, identified with high-resolution microscopic autoradiography. Throughout the digestive system numerous sites with nuclear receptor binding of 3H-1,25(OH)2 vitamin D3 and 3H-OCT exist: in the oral region, epithelial cells of the oral cavity, tongue and gingiva, teeth odontoblast and ameloblast precursor pulp and stratum intermedium cells; in the parotid, submandibular and sublingual salivary glands, epithelial cells of striated ducts and granular convoluted tubules, intercalated ducts and acinar cells, as well as myoepithelial cells; in the stomach, neck mucous cells of gastric glands, endocrine cells of the antrum, and muscle cells of the pyloric sphincter; in the small and large intestine, absorptive and crypt epithelial cells; in the pancreas, predominantly islet B-cells. Perisinusoidal stellate (Ito) cells in the liver concentrate and retain variable amounts of radiolabeled compound in regions of their cytoplasm after administration of 3H-I,25(OH)2 vitamin D3 and 3H-25(OH) vitamin D3, probably sites of specific storage, similar to vitamin A. Submucosa in stomach and intestine also retain variable amounts of radiolabel, however unspecific with all compounds studied. In pilot studies with 3H-25(OH)2 vitamin D3 and 3H-24,25(OH)2 vitamin D3, no nuclear concentration was detectable. The reviewed data for vitamin D and its oxygen analogue OCT indicate genomic effects on multiple target tissues of the digestive system that involve cell proliferation and differentiation, endo- and exocrine secretion, digestion and absorption for maintaining optimal functions, with potentials for health prophylaxis and therapies.

  18. Calcium and Vitamin D: Skeletal and Extraskeletal Health

    PubMed Central

    Khazai, Natasha; Judd, Suzanne E.; Tangpricha, Vin

    2009-01-01

    Vitamin D is known for its role in calcium homeostasis for optimal skeletal health. It was previously believed that only elderly or hospitalized patients were at risk for vitamin D insufficiency, but many people in the general US population have insufficient levels of 25-hydroxyvitamin D (25[OH]D). According to the Third National Health and Nutrition Examination Survey, 61% of white and 91% of black Americans suffer from vitamin D insufficiency (25[OH]D < 32 ng/mL). Recent studies have demonstrated that a minimum 25(OH)D level of 32 ng/mL is necessary for optimal protection from fracture and intestinal absorption of calcium. Recently, vitamin D has been recognized as important for extraskeletal functions such as immune function, cancer prevention, and hypertension prevention. We review the role of vitamin D in skeletal health and present data on vitamin D in other extraskeletal diseases, with special emphasis on the rheumatology patient. PMID:18460265

  19. Vitamin D supplementation increases calcium absorption without a threshold effect

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The maximal calcium absorption in response to vitamin D has been proposed as a biomarker for vitamin D sufficiency. Our objective was to determine whether there is a threshold beyond which increasing doses of vitamin D, or concentrations of serum 25-hydroxyvitamin D [25(OH)D], no longer increase cal...

  20. Determination of four sulfated vitamin D compounds in human biological fluids by liquid chromatography-tandem mass spectrometry.

    PubMed

    Gomes, Fabio P; Shaw, P Nicholas; Hewavitharana, Amitha K

    2016-01-15

    The determination of both the water-soluble and lipid-soluble vitamin D compounds in human biological fluids is necessary to illuminate potentially significant biochemical mechanisms. The lack of analytical methods to quantify the water-soluble forms precludes studies on their role and biological functions; currently available liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods are able to determine only a single sulfated form of Vitamin D. We describe here a highly sensitive and specific LC-MS/MS method for the quantification of four sulfated forms of vitamin D: vitamins D2- and D3-sulfate (D2-S and D3-S) and 25-hydroxyvitamin D2- and D3-sulfate (25(OH)D2-S and 25(OH)D3-S). A comparative evaluation showed that the ionization efficiencies of underivatized forms in negative ion mode electrospray ionisation (ESI) are superior to those of the derivatized (using 4-phenyl-l,2,4-triazoline-3,5-dione (PTAD)) forms in positive ion mode ESI. Separation was optimised to minimise co-elution with endogenous matrix compounds, thereby reducing ion suppression/enhancement effects. Isotopically labelled analogues of each compound were used as internal standards to correct for ion suppression/enhancement effects. The method was validated and then applied for the analysis of breastmilk and human serum. The detection limits, repeatability standard deviations, and recoveries ranged from 0.20 to 0.28fmol, 2.8 to 10.2%, and 81.1 to 102%, respectively.

  1. 1,25(OH)2D3 Deficiency Induces Colon Inflammation via Secretion of Senescence-Associated Inflammatory Cytokines

    PubMed Central

    Zhi, Chunchun; Shen, Ming; Sun, Weiwei; Miao, Dengshun; Yuan, Xiaoqin

    2016-01-01

    Epidemiological studies showed that 1,25-Dihydroxyvitamin D[1,25(OH)2D3] insufficiency appears to be associated with aging and colon cancer while underlying biological mechanisms remain largely unknown. Inflammatory bowel disease is one of the risk factors for colon cancer. In this study, we investigated whether 1,25(OH)2D3 deficiency has an impact on the colon of 25-hydroxyvitamin D 1α-hydroxylase knockout [Cyp27b1−/−] mice fed on a rescue diet (high calcium, phosphate, and lactose) from weaning to 10 months of age. We found that 1,25(OH)2D3 deficient mice displayed significant colon inflammation phenotypes including shortened colon length, thinned and disordered mucosal structure, and inflammatory cell infiltration. DNA damage, cellular senescence and the production of senescence-associated inflammatory cytokines were also increased significantly in the colon of Cyp27b1−/−mice. Furthermore, the levels of ROS in the colon were increased significantly, whereas the expression levels of antioxidative genes were down-regulated dramatically in the colon of Cyp27b1−/−mice. Taken together, our results demonstrated that 1,25(OH)2D3 deficiency could induce colon inflammation, which may result from increased oxidative stress and DNA damage, subsequently, induced cell senescence and overproduction of senescence-associated secretory factors. Therefore, our findings suggest that 1,25(OH)2D3 may play an important role in preventing the development and progression of colon inflammation and colon cancer. PMID:26790152

  2. Extracts from Lentinula edodes (Shiitake) Edible Mushrooms Enriched with Vitamin D Exert an Anti-Inflammatory Hepatoprotective Effect.

    PubMed

    Drori, Ariel; Shabat, Yehudit; Ben Ya'acov, Ami; Danay, Ofer; Levanon, Dan; Zolotarov, Lidya; Ilan, Yaron

    2016-04-01

    Vitamin D has been known for its anti-inflammatory properties. Extracts derived from Lentinula edodes (Shiitake) edible mushroom exert an anti-inflammatory effect. These extracts contain high levels of ergosterol, which converts into ergocalciferol (vitamin D2) following exposure to ultraviolet light, followed by absorption and hydroxylation into the active form 25-hydroxyvitamin D [25(OH)D]. To determine the anti-inflammatory effect of overexpression of vitamin D in edible mushrooms, L. edodes mushrooms were exposed to ultraviolet-B light, freeze-dried, followed by measurement of vitamin D2 contents, in their dry weight. C57B1/6 mice were orally treated with vitamin D2-enriched or nonenriched mushroom extract prior and during concanavalin A-immune-mediated liver injury. Exposure to ultraviolet light increased vitamin D2 content in Shiitake edible mushrooms. Following feeding of vitamin D-enriched mushroom extracts to mice with immune-mediated hepatitis, a significant decrease in liver damage was noted. This was shown by a decrease in alanine aminotransferase and aspartate aminotransferase serum levels, a decrease in proportion of mice with severe liver injury, and by improvement in liver histology. These effects were associated with a decrease in serum interferon gamma levels. A synergistic effect was noted between the anti-inflammatory effect of the mushroom extracts and that of vitamin D. Oral administration of vitamin D-enriched L. edodes edible mushroom exerts a synergistic anti-inflammatory effect in the immune-mediated hepatitis. The data support its potential use as safe immunomodulatory adjuvant for the treatment of HCV and nonalcoholic steatohepatitis.

  3. Replete vitamin D stores predict reproductive success following IVF

    PubMed Central

    Ozkan, Sebiha; Jindal, Sangita; Greenseid, Keri; Shu, Jun; Zeitlian, Gohar; Hickmon, Cheryl; Pal, Lubna

    2009-01-01

    Objective Hypothesizing that levels of 25OH-D in body fluids are reflective of vitamin repletion status, we aimed to determine if 25OH-D levels in the follicular fluid (FF) of infertile women undergoing in vitro fertilization (IVF) demonstrate a relationship with IVF cycle parameters and outcome. Design Prospective Cohort study Setting Academic tertiary care center Patients 84 infertile women undergoing IVF Interventions FF from follicles ≥14mm; serum (n=10) and FF levels of 25OH-D Main outcome measures Clinical pregnancy (CP) (defined as evidence of intrauterine gestation sac on ultrasound) following IVF; IVF cycle parameters. Results Serum and FF levels of 25OH-D were highly correlated (r=0.94, p<0.001). In a predominantly Caucasian population (66%), significantly lower FF 25OH-D levels were noted in Black versus non-Black patients (p=0.001). Significant inverse correlations were seen between FF 25OH-D levels and BMI (r−0.25, p=0.035). Significantly higher CP and implantation rates were observed across tertiles of FF25OH-D (p=0.029 and p=0.041 respectively); patients achieving CP following IVF (n=26) exhibited significantly higher FF levels of 25OH-D (p=0.005). Multivariable logistic regression analysis confirmed FF 25OH-D levels as an independent predictor to success of an IVF cycle; adjusting for age, BMI, ethnicity and number of embryos transferred (ET) each ng/ml increase in FF 25OH-D increased the likelihood for achieving CP by 6% (p=0.030). Conclusion Our findings that women with higher vitamin D level in their serum and FF are significantly more likely to achieve CP following IVF-ET are novel. A potential for benefit of vitamin D supplementation on treatment success in infertile patients undergoing IVF is suggested that merits further investigation. PMID:19589516

  4. Potential effect of 25-Hydroxyvitamin D in foods on differences in measures of vitamin D status

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The discrepancy between the commonly used vitamin D status measures—intake and serum 25(OH)D concentrations—has been perplexing. Sun exposure increases serum 25(OH)D concentrations, and is often used as an explanation for the higher population-based serum concentrations in the face of apparently low...

  5. Current Scenario of Prevalence of Vitamin D Deficiency in Ostensibly Healthy Indian Population: A Hospital Based Retrospective Study.

    PubMed

    Shukla, Kirtikar; Sharma, Shikha; Gupta, Aditi; Raizada, Arun; Vinayak, Kamini

    2016-10-01

    25-hydroxy vitamin D [25(OH) vit D] deficiency is a serious public health problem, particularly in the Indian sub-continent. The objective of the present study was to study the prevalence of 25(OH) vit D in different age groups. The data of 25(OH) vit D assay of 26,346 ostensibly healthy individuals, enrolled under executive health checkup at Medanta The Medicity, Gurgaon, over a period of 3 years, were extracted from the hospital information system and reviewed extensively. 25(OH) vit D deficiency (VDD) was defined as 25(OH) vit D < 20 ng/ml, insufficiency (VDI) as 25(OH) vit D between 20 and 40 ng/ml and 25(OH) vit D sufficiency (VDS) as 25(OH) D > 40 ng/mL. 25(OH) vit D deficiency (VDD + VDI) was observed in 93 % of the subject population. Maximum number of the subjects belonged to the age group of 41-60 years. 59 % had frank 25(OH) vit D deficiency when cut off level was <20 ng/mL. Mean value of 25(OH) vit D in our subjects was 21.4 ± 14.4 ng/mL. Significant difference in 25(OH) vit D level was observed in between male and female subjects. Simultaneously 25(OH) vit D levels were significantly lower in the patient visited hospital in winter-spring season than the summer-autumn season (p > 0.001). Our study demonstrates a high prevalence of 25(OH) vit D deficiency in an ostensibly healthy Indian population. There is a need for redefining our reference ranges according to our population and extensively improving the status of vitamin D.

  6. Quantifying the food sources of basal vitamin d input.

    PubMed

    McDonnell, Sharon L; French, Christine B; Heaney, Robert P

    2014-10-01

    Cutaneous synthesis and traditional food sources do not fully account for unsupplemented vitamin D status. Non-traditional food sources may be an undiscovered input. In a cohort of 780 non-supplement-taking adults with a mean serum 25-hydroxyvitamin D [25(OH)D] of 33 (±14)ng/ml we assessed the relationship between vitamin D status and selected food sources. Serum 25(OH)D concentration was adjusted for season, UVB exposures, and body size. These adjusted values were then regressed against multiple food items and combinations. Whole milk cottage cheese, eggs, red meat, and total protein were positively associated with total 25(OH)D and/or 25(OH)D3 (P<0.05 for each), whereas fish and milk intake were not. The slope of the relationship was such that for every intake of 1serving/day, serum 25(OH)D rose by about 2ng/ml for eggs and 1ng/ml for meat and total protein. For every weekly serving of whole milk cottage cheese, serum 25(OH)D rose by about 1ng/ml. While some food sources were significant predictors of vitamin D status, their ability to explain inter-individual variability was limited. Supplementation will likely remain essential to improving vitamin D status on a population level. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.

  7. [Current Topics on Vitamin D. The vitamin D functions in keratinocytes and its therapeutic applications].

    PubMed

    Sawatsubashi, Shun

    2015-03-01

    1,25 (OH) 2D and calcium have been shown to promote epidermal keratinocyte differentiation and prevent proliferation. These prodifferentiation and antiproliferative effects of 1,25 (OH) 2D have led to its clinical use in the treatment of psoriasis. However, the mechanism of vitamin D action on keratinocytes remains largely unknown. While the actions of calcium and the vitamin D receptor signaling pathways on epidermal keratinocyte differentiation are redundant, their effects on the hair follicle are not. In this review, we discuss how the vitamin D and its receptor contribute to skin and hair follicle homeostasis.

  8. Education and communication is the key for the successful management of vitamin D test requesting

    PubMed Central

    López-Garrigós, Maite; Flores, Emilio; Leiva-Salinas, María; Ahumada, Miguel; Leiva-Salinas, Carlos

    2015-01-01

    Introduction Pre-preanalytical and post-postanalytical phases are steps where the laboratory professional may play a crucial role. Measuring the serum circulating 25 hydroxyvitamin D level (25(OH)D) is recommended to evaluate vitamin D status in patients at risk for vitamin D deficiency while 1,25 hydroxyvitamin D (1,25(OH)2D) is only recommended to monitor several particular conditions (chronic kidney disease, hereditary phosphate-losing disorders, and some other) clearly defined by the current clinical guidelines of Endocrine Society.
Our research hypothesis was that through education and communication through comments in the Laboratory Information System (LIS), we could improve appropriateness in the request vitamin D tests. Materials and methods A retrospective observational cross-sectional study was conducted from January 2005 to December 2014. Each 1,25(OH)2D request was reviewed individually by a member of the laboratory staff. Starting in November 2011, each inappropriate 1,25(OH)2D request was registered in LIS and 25(OH)D was measured instead of 1,25(OH)2D. We counted the overall number of 1,25(OH)2D requests and the number of inappropriate requests which then were marked with a comment. Results The request of 25(OH)D increased along years. However, 1,25(OH)2D requests increased until 2012 when demand began to diminish. Conclusions Education and communication through comments in the LIS, corrected the inappropriate request of 1,25(OH)2D and promoted the use of 25(OH)D to study vitamin D deficiency. PMID:26110036

  9. Vitamin D in incident nephrotic syndrome: a Midwest Pediatric Nephrology Consortium study

    PubMed Central

    Chen, Ashton; Shatat, Ibrahim F.; Pais, Priya; Greenbaum, Larry A.; Geier, Pavel; Nelson, Raoul D.; Kiessling, Stefan G.; Brophy, Patrick D.; Quiroga, Alejandro; Seifert, Michael E.; Straatmann, Caroline E.; Mahan, John D.; Ferris, Maria E.; Troost, Jonathan P.; Gipson, Debbie S.

    2016-01-01

    Background Cross-sectional studies of children with prevalent nephrotic syndrome (NS) have shown 25-vitamin D (25(OH)D) deficiency rates of 20–100 %. Information on 25(OH)D status in incident patients or following remission is limited. This study aimed to assess 25(OH)D status of incident idiopathic NS children at presentation and longitudinally with short-term observation. Methods Multicenter longitudinal study of children (2–18 years old) from 14 centers across the Midwest Pediatric Nephrology Consortium with incident idiopathic NS. 25(OH)D levels were assessed at diagnosis and 3 months later. Results Sixty-one children, median age 5 (3, 11) years, completed baseline visit and 51 completed second visit labs. All 61 (100 %) had 25(OH)D<20 ng/ml at diagnosis. Twenty-seven (53 %) had 25(OH)D<20 ng/ml at follow-up. Fourteen (28 %) children were steroid resistant. Univariate analysis showed that children prescribed vitamin D supplements were less likely to have 25(OH)D deficiency at follow-up (OR 0.2, 95 % CI 0.04, 0.6). Steroid response, age, and season did not predict 25(OH)D deficiency. Multivariable linear regression modeling showed higher 25(OH)D levels at follow-up by 13.2 ng/ml (SE 4.6, p<0.01) in children supplemented with vitamin D. Conclusions In this incident idiopathic NS cohort, all children at diagnosis had 25(OH)D deficiency and the majority continued to have a deficiency at 2–4 months. Supplemental vitamin D decreased the odds of 25(OH)D deficiency at follow-up, supporting a role for supplementation in incident NS. PMID:26498119

  10. Determination of vitamins D2 and D3 in selected food matrices by online high-performance liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS).

    PubMed

    Nestola, Marco; Thellmann, Andrea

    2015-01-01

    An online normal-phase liquid chromatography-gas chromatography-mass spectrometry (HPLC-GC-MS) method was developed for the determination of vitamins D2 and D3 in selected food matrices. Transfer of the sample from HPLC to GC was realized by large volume on-column injection; detection was performed with a time-of-flight mass spectrometer (TOF-MS). Typical GC problems in the determination of vitamin D such as sample degradation or sensitivity issues, previously reported in the literature, were not observed. Determination of total vitamin D content was done by quantitation of its pyro isomer based on an isotopically labelled internal standard (ISTD). Extracted ion traces of analyte and ISTD showed cross-contribution, but non-linearity of the calibration curve was not determined inside the chosen calibration range by selection of appropriate quantifier ions. Absolute limits of detection (LOD) and quantitation (LOQ) for vitamins D2 and D3 were calculated as approximately 50 and 150 pg, respectively. Repeatability with internal standard correction was below 2 %. Good agreement between quantitative results of an established high-performance liquid chromatography with UV detection (HPLC-UV) method and HPLC-GC-MS was found. Sterol-enriched margarine was subjected to HPLC-GC-MS and HPLC-MS/MS for comparison, because HPLC-UV showed strong matrix interferences. HPLC-GC-MS produced comparable results with less manual sample cleanup. In summary, online hyphenation of HPLC and GC allowed a minimization in manual sample preparation with an increase of sample throughput.

  11. Calcium and vitamin D metabolism in spontaneously hypertensive rats

    SciTech Connect

    Hsu, Chen Hsing; Yang, Chweishiun; Patel, S.R.; Stevens, M.G. )

    1987-10-01

    The authors have studied the effect of dietary vitamin D restriction on serum levels of vitamin D metabolites, measured by radioreceptor assay and radioimmunoassay in spontaneously hypertensive rats (SHR) and normotensive Wistar-Kyoto rats (WKY). Both WKY and SHR were fed a vitamin D-deficient or a vitamin D-supplemented diet beginning at 4 wk of age. In vitamin D-supplemented animals, the serum 1,25-dihydroxycholecalciferol (1,25(OH){sub 2}D{sub 3}) concentration of WKY was similar to the level of SHR. Plasma calcium concentration was not different between WKY and SHR. In animals fed a vitamin D-deficient diet, the serum concentration of 1,25-(OH){sub 2}D{sub 3} of SHR was significantly lower than that of WKY. Plasma 25-hydroxycholecalciferol level was markedly decreased in both WKY and SHR. The SHR, but not the WKY, developed hypocalcemia. Despite hypocalcemia, fasting urinary Ca{sup 2+} excretion of SHR exceeded that of WKY. They conclude that the lower 1,25(OH){sub 2}D{sub 3} level in SHR fed a vitamin D-deficient diet may be due to a defect in the synthesis of 1,25(OH){sub 2}D{sub 3}. The low level of 1,25(OH){sub 2}D{sub 3} is associated with renal wasting of calcium and hypocalcemia in SHR.

  12. Tumoral vitamin D synthesis by CYP27B1 1-alpha-hydroxylase delays mammary tumor progression in the PyMT-MMTV mouse model and its action involves NF-kappaB modulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biologically-active vitamin D (1,25(OH)2D) is synthetized from inactive prohormone 25(OH)D by the enzyme CYP27B1 1-a-hydroxylase in kidney and several extra-renal tissues including breast. While the development of breast cancer has been linked to inadequate vitamin D status, the importance of bioac...

  13. Erythrocyte fatty acid composition does not influence levels of free, bioavailable, and total 25-hydroxy vitamin D.

    PubMed

    Carlsson, Martin; Nilsson, Ingela; Brudin, Lars; Von, Siv-Ping; Wanby, Pär

    2017-02-01

    In vitro, mono- and polyunsaturated fatty acids (FAs) may decrease the binding affinity of vitamin D metabolites for vitamin D-binding protein, which in turn may influence their bioavailability. FAs incorporated as phospholipids in erythrocyte (ery-) cell membranes reflect dietary intake. The purpose of this study was to investigate ery-FA composition in relation to markers for vitamin D. In healthy females (age 22.6 ± 2.0 years) total 25(OH)D was measured by LC-MS/MS (n = 78), free 25(OH)D with ELISA (n = 64 of 78), and bioavailable 25(OH)D was calculated. Analysis of ery-FA composition was by gas chromatography (n = 56 of 78). A strong correlation between total 25(OH)D and free 25(OH)D was seen (r = .66, p < .001), and between total-25(OH)D and bioavailable 25(OH)D (r = .68, p < .001). No correlations between 25(OH)D fractions and specific fatty acids were found, and in particular, no associations with mono- and poly-unsaturated FA compositions. All 25(OH)D fractions were correlated with leptin (total 25(OH)D (r = -.33, p < .003); bioavailable 25(OH)D (r = -.47, p < .001); free 25(OH)D (r = -.44, p < .001). Associations were found between PTH and total 25(OH)D (r = -.35, p = .002) and weaker between bioavailable 25(OH)D (r = -.35, p = .040) and free 25(OH)D (r = -.28, p = .079). All fractions of 25(OH)D appear to correlate in a similar way to PTH, BMI and body fat (leptin). No association was found between ery-FA composition and free/bioavailable 25(OH)D. It is unlikely that FAs are a strong uncoupling factor of DBP-bound 25(OH)D.

  14. Counter-regulatory paracrine actions of FGF-23 and 1,25(OH)2 D in macrophages.

    PubMed

    Han, Xiaobin; Li, Linqiang; Yang, Jiancheng; King, Gwendalyn; Xiao, Zhousheng; Quarles, Leigh Darryl

    2016-01-01

    Mechanisms underlying the association between fibroblastic growth factor 23 (FGF-23) and inflammation are uncertain. We found that FGF-23 was markedly up-regulated in LPS/INF-γ-induced proinflammatory M1 macrophages and Hyp mouse-derived peritoneal macrophages, but not in IL-4-induced M2 anti-inflammatory macrophages. NF-КB and JAK/STAT1 pathways mediated the increased transcription of FGF-23 in response to M1 polarization. FGF-23 stimulated TNF-α, but not IL-6, expression in M0 macrophages and suppressed Arginase-1 expression in M2 macrophages through FGFR-mediated mechanisms. 1,25(OH)2 D stimulated Arginase-1 expression and inhibited FGF-23 stimulation of TNF-α. FGF-23 has proinflammatory paracrine functions and counter-regulatory actions to 1,25(OH)2 D on innate immune responses.

  15. Counter-regulatory paracrine actions of FGF-23 and 1,25(OH)2D in macrophages

    PubMed Central

    Han, Xiaobin; Li, Linqiang; Yang, Jiancheng; King, Gwendalyn; Xiao, Zhousheng; Quarles, Leigh Darryl

    2016-01-01

    Mechanisms underlying the association between fibroblastic growth factor 23 (FGF-23) and inflammation are uncertain. We found that FGF-23 was markedly up-regulated in LPS/INF-γ-induced proinflammatory M1 macrophages and Hyp mouse-derived peritoneal macrophages, but not in IL-4-induced M2 anti-inflammatory macrophages. NF-κB and JAK/STAT1 pathways mediated the increased transcription of FGF-23 in response to M1 polarization. FGF-23 stimulated TNF-α, but not IL-6, expression in M0 macrophages and suppressed Arginase-1 expression in M2 macrophages through FGFR-mediated mechanisms. 1,25(OH)2D stimulated Arginase-1 expression and inhibited FGF-23 stimulation of TNF-α. FGF-23 has proinflammatory paracrine functions and counter-regulatory actions to 1,25(OH)2D on innate immune responses. PMID:26762170

  16. [Current Topics on Vitamin D. Evolution of animals and vitamin D].

    PubMed

    Suda, Tatsuo

    2015-03-01

    Vitamin D3 is already found in the early evolution of life, but essentially as inactive products of the photochemical reaction of 7-dehydrocholesterol. The full vitamin D endocrine system characterized by the specific vitamin D transport protein (DBP) , specific vitamin D-metabolizing CYP P450 enzymes, active vitamin D metabolites, 1α,25 (OH) 2D3, specific vitamin D nuclear receptor (VDR), and fibroblast growth factor 23 (FGF23) became essential for maintaining calcium and bone homeostasis in terrestrial animals cope with the challenging of higher gravity and calcium-poor environment. The present review describes the story about the evolution of animals and vitamin D.

  17. Vitamin D measurement standardization: The way out of the chaos.

    PubMed

    Binkley, N; Dawson-Hughes, B; Durazo-Arvizu, R; Thamm, M; Tian, L; Merkel, J M; Jones, J C; Carter, G D; Sempos, C T

    2016-12-12

    Substantial variability is associated with laboratory measurement of serum total 25-hydroxyvitamin D [25(OH)D]. The resulting chaos impedes development of consensus 25(OH)D values to define stages of vitamin D status. As resolving this situation requires standardized measurement of 25(OH)D, the Vitamin D Standardization Program (VDSP) developed methodology to standardize 25(OH)D measurement to the gold standard reference measurement procedures of NIST, Ghent University and CDC. Importantly, VDSP developed protocols for standardizing 25(OH)D values from prior research based on availability of stored serum samples. The effect of such retrospective standardization on prevalence of "low" vitamin D status in national studies reported here for The Third National Health and Nutrition Examination Survey (NHANES III, 1988-1994) and the German Health Interview and Examination Survey for Children and Adolescents (KIGGS, 2003-2006) was such that in NHANES III 25(OH)D values were lower than original values while higher in KIGGS. In NHANES III the percentage with values below 30, 50 and 75 nmol/L increased from 4% to 6%, 22% to 31% and 55% to 71%, respectively. Whereas in KIGGS after standardization the percentage below 30, 50, and 70 nmol/L decreased from 28% to 13%, 64% to 47% and 87% to 85% respectively. Moreover, in a hypothetical example, depending on whether the 25(OH)D assay was positively or negatively biased by 12%, the 25(OH)D concentration which maximally suppressed PTH could vary from 20 to 35ng/mL. These examples underscore the challenges (perhaps impossibility) of developing vitamin D guidelines using unstandardized 25(OH)D data. Retrospective 25(OH)D standardization can be applied to old studies where stored serum samples exist. As a way forward, we suggest an international effort to identify key prior studies with stored samples for re-analysis and standardization initially to define the 25(OH)D level associated with vitamin D deficiency (rickets

  18. Vitamin D Intake and Serum 25-Hydroxyvitamin D Levels in Korean Adults: Analysis of the 2009 Korea National Health and Nutrition Examination Survey (KNHANES IV-3) Using a Newly Established Vitamin D Database

    PubMed Central

    Yoo, Kyoungok; Cho, Jinah; Ly, Sunyung

    2016-01-01

    Vitamin D is important for maintaining bone health and may prevent various diseases (i.e., cardiovascular disease and cancer). The aim of this study was to estimate vitamin D intakes of Korean adults using the Korea National Health and Nutrition Examination Survey (KNHANES, 2009) data and a newly established vitamin D database. KNHANES (2009) participants (n = 4541; 2021 men; 2520 women) aged ≥20 years were included. Dietary vitamin D intake, serum 25-hydroxyvitamin D (25(OH)D), and the relationship between vitamin D intake and serum 25(OH)D were evaluated. In men and women, vitamin D intakes were 4.00 ± 0.17 µg/day and 2.6 ± 0.1 µg/day respectively, and serum 25(OH)D concentrations were 19.78 ± 0.33 ng/mL and 17.10 ± 0.26 ng/mL respectively. Serum 25(OH)D concentrations of men aged <50 years and women aged >20 years were under 20 ng/mL. After adjusting for confounding factors, the positive relationship between vitamin D intake and serum 25(OH)D was observed in total subjects (p < 0.05), excluding participants ≥50 years old. The main food sources for vitamin D among Korean adults were fish/shellfish (71.34%) and egg (14.89%). Korean adults should increase their serum 25(OH)D concentrations by increasing vitamin D intake. PMID:27690097

  19. Vitamin D and Muscle Function.

    PubMed

    Dawson-Hughes, Bess

    2017-03-21

    Muscle weakness is a hallmark of severe vitamin D deficiency, but the effect of milder vitamin D deficiency or insufficiency on muscle mass and performance and risk of falling is uncertain. In this presentation, I review the evidence that vitamin D influences muscle mass and performance, balance, and risk of falling in older adults. Special consideration is given to the impact of both the starting 25-hydroxyvitamin D [25(OH)D] level and the dose administered on the clinical response to supplemental vitamin D in older men and women. Based on available evidence, older adults with serum 25(OH)D levels <40nmol/L appear most likely to improve their muscle performance with supplementation. The vitamin D dose range of 800-1000 IU per day has been effective in many studies; lower doses have generally been ineffective and several doses above this range have increased the risk of falls. In conclusion, older adults with serum 25(OH)D levels <40nmol/L are likely to have fewer falls if supplemented with 800 to 1,000 IU per day of vitamin D.

  20. Vitamin D Promotes Odontogenic Differentiation of Human Dental Pulp Cells via ERK Activation

    PubMed Central

    Woo, Su-Mi; Lim, Hae-Soon; Jeong, Kyung-Yi; Kim, Seon-Mi; Kim, Won-Jae; Jung, Ji-Yeon

    2015-01-01

    The active metabolite of vitamin D such as 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3) is a well-known key regulatory factor in bone metabolism. However, little is known about the potential of vitamin D as an odontogenic inducer in human dental pulp cells (HDPCs) in vitro. The purpose of this study was to evaluate the effect of vitamin D3 metabolite, 1α,25(OH)2D3, on odontoblastic differentiation in HDPCs. HDPCs extracted from maxillary supernumerary incisors and third molars were directly cultured with 1α,25(OH)2D3 in the absence of differentiation-inducing factors. Treatment of HDPCs with 1α,25(OH)2D3 at a concentration of 10 nM or 100 nM significantly upregulated the expression of dentin sialophosphoprotein (DSPP) and dentin matrix protein1 (DMP1), the odontogenesis-related genes. Also, 1α,25(OH)2D3 enhanced the alkaline phosphatase (ALP) activity and mineralization in HDPCs. In addition, 1α,25(OH)2D3 induced activation of extracellular signal-regulated kinases (ERKs), whereas the ERK inhibitor U0126 ameliorated the upregulation of DSPP and DMP1 and reduced the mineralization enhanced by 1α,25(OH)2D3. These results demonstrated that 1α,25(OH)2D3 promoted odontoblastic differentiation of HDPCs via modulating ERK activation. PMID:26062551

  1. Vitamin D Status Predicts 30 Day Mortality in Hospitalised Cats

    PubMed Central

    Titmarsh, Helen; Kilpatrick, Scott; Sinclair, Jennifer; Boag, Alisdair; Bode, Elizabeth F.; Lalor, Stephanie M.; Gaylor, Donna; Berry, Jacqueline; Bommer, Nicholas X.; Gunn-Moore, Danielle; Reed, Nikki; Handel, Ian; Mellanby, Richard J.

    2015-01-01

    Vitamin D insufficiency, defined as low serum concentrations of the major circulating form of vitamin D, 25 hydroxyvitamin D (25(OH)D), has been associated with the development of numerous infectious, inflammatory, and neoplastic disorders in humans. In addition, vitamin D insufficiency has been found to be predictive of mortality for many disorders. However, interpretation of human studies is difficult since vitamin D status is influenced by many factors, including diet, season, latitude, and exposure to UV radiation. In contrast, domesticated cats do not produce vitamin D cutaneously, and most cats are fed a commercial diet containing a relatively standard amount of vitamin D. Consequently, domesticated cats are an attractive model system in which to examine the relationship between serum 25(OH)D and health outcomes. The hypothesis of this study was that vitamin D status would predict short term, all-cause mortality in domesticated cats. Serum concentrations of 25(OH)D, together with a wide range of other clinical, hematological, and biochemical parameters, were measured in 99 consecutively hospitalised cats. Cats which died within 30 days of initial assessment had significantly lower serum 25(OH)D concentrations than cats which survived. In a linear regression model including 12 clinical variables, serum 25(OH)D concentration in the lower tertile was significantly predictive of mortality. The odds ratio of mortality within 30 days was 8.27 (95% confidence interval 2.54-31.52) for cats with a serum 25(OH)D concentration in the lower tertile. In conclusion, this study demonstrates that low serum 25(OH)D concentration status is an independent predictor of short term mortality in cats. PMID:25970442

  2. Body size and serum 25 hydroxy vitamin D response to oral supplements in healthy older adults

    PubMed Central

    Blum, Miriam; Dallal, Gerard E.; Dawson-Hughes, Bess

    2009-01-01

    Vitamin D insufficiency is prevalent in the northeast United States. Since vitamin D insufficiency is readily amenable to supplementation, it is important to understand what factors are associated with serum 25 hydroxy vitamin D (25(OH)D) response to vitamin D supplementation. Objective In this study we examined the association of serum 25(OH)D response to vitamin D supplementation with body size in a population of elderly subjects. Methods 257 healthy, ambulatory men and women 65 years of age or older were randomly assigned to treatment with either 700 IU/day (17.5 μg/d) of supplemental vitamin D3 and 500 mg/day (12.5 mmol/d) of supplemental calcium, or to placebo. Results In multivariate regression analyses, after adjusting for baseline 25(OH)D, season, and sex, we found change in 25(OH)D to be inversely associated with baseline BMI (p = 0.01) in subjects treated with supplements for one year. Change in 25(OH)D was also negatively associated with other baseline anthropometric measurements in these subjects. Conclusion Our study implies that body size should be taken into account when estimating the amount of vitamin D intake needed to raise 25(OH)D to the desired level. PMID:18689559

  3. Including food 25-hydroxyvitamin D in intake estimates may reduce the discrepancy between dietary and serum measures of vitamin D status.

    PubMed

    Taylor, Christine L; Patterson, Kristine Y; Roseland, Janet M; Wise, Stephen A; Merkel, Joyce M; Pehrsson, Pamela R; Yetley, Elizabeth A

    2014-05-01

    The discrepancy between the commonly used vitamin D status measures-intake and serum 25-hydroxyvitamin D [25(OH)D] concentrations--has been perplexing. Sun exposure increases serum 25(OH)D concentrations and is often used as an explanation for the higher population-based serum concentrations in the face of apparently low vitamin D intake. However, sun exposure may not be the total explanation. 25(OH)D, a metabolite of vitamin D, is known to be present in animal-based foods. It has been measured and reported only sporadically and is not currently factored into U.S. estimates of vitamin D intake. Previously unavailable preliminary USDA data specifying the 25(OH)D content of a subset of foods allowed exploration of the potential change in the reported overall vitamin D content of foods when the presence of 25(OH)D was included. The issue of 25(OH)D potency was addressed, and available commodity intake estimates were used to outline trends in projected vitamin D intake when 25(OH)D in foods was taken into account. Given the data available, there were notable increases in the total vitamin D content of a number of animal-based foods when potency-adjusted 25(OH)D was included, and in turn there was a potentially meaningful increase (1.7-2.9 μg or 15-30% of average requirement) in vitamin D intake estimates. The apparent increase could reduce discrepancies between intake estimates and serum 25(OH)D concentrations. The relevance to dietary interventions is discussed, and the need for continued exploration regarding 25(OH)D measurement is highlighted.

  4. 1alpha,25(OH)2D3 causes a rapid increase in phosphatidylinositol-specific PLC-beta activity via phospholipase A2-dependent production of lysophospholipid.

    PubMed

    Schwartz, Z; Shaked, D; Hardin, R R; Gruwell, S; Dean, D D; Sylvia, V L; Boyan, B D

    2003-05-01

    1alpha,25(OH)(2)D(3) activates protein kinase C (PKC) in rat growth plate chondrocytes via mechanisms involving phosphatidylinositol-specific phospholipase C (PI-PLC) and phospholipase A(2) (PLA(2)). The purpose of this study was to determine if 1alpha,25(OH)(2)D(3) activates PI-PLC directly or through a PLA(2)-dependent mechanism. We determined which PLC isoforms are present in the growth plate chondrocytes, and determined which isoform(s) of PLC is(are) regulated by 1alpha,25(OH)(2)D(3). Inhibitors and activators of PLA(2) were used to assess the inter-relationship between these two phospholipid-signaling pathways. PI-PLC activity in lysates of prehypertrophic and upper hypertrophic zone (growth zone) cells that were incubated with 1alpha,25(OH)(2)D(3), was increased within 30s with peak activity at 1-3 min. PI-PLC activity in resting zone cells was unaffected by 1alpha,25(OH)(2)D(3). 1beta,25(OH)(2)D(3), 24R,25(OH)(2)D(3), actinomycin D and cycloheximide had no effect on PLC in lysates of growth zone cells. Thus, 1alpha,25(OH)(2)D(3) regulation of PI-PLC enzyme activity is stereospecific, cell maturation-dependent, and nongenomic. PLA(2)-activation (mastoparan or melittin) increased PI-PLC activity to the same extent as 1alpha,25(OH)(2)D(3); PLA(2)-inhibition (quinacrine, oleyloxyethylphosphorylcholine (OEPC), or AACOCF(3)) reduced the effect of 1alpha,25(OH)(2)D(3). Neither arachidonic acid (AA) nor its metabolites affected PI-PLC. In contrast, lysophosphatidylcholine (LPC) and lysophosphatidylethanolamine (LPE) activated PI-PLC (LPE>LPC). 1alpha,25(OH)(2)D(3) stimulated PI-PLC and PKC activities via Gq; GDPbetaS inhibited activity, but pertussis toxin did not. RT-PCR showed that the cells express PLC-beta1a, PLC-beta1b, PLC-beta3 and PLC-gamma1 mRNA. Antibodies to PLC-beta1 and PLC-beta3 blocked the 1alpha,25(OH)(2)D(3) effect; antibodies to PLC-delta and PLC-gamma did not. Thus, 1alpha,25(OH)(2)D(3) regulates PLC-beta through PLA(2)-dependent production of

  5. Vitamin D deficiency in rheumatoid arthritis: prevalence, determinants and associations with disease activity and disability

    PubMed Central

    2010-01-01

    Introduction The aim of this study was to estimate the prevalence and determinants of vitamin D deficiency in patients with rheumatoid arthritis (RA) as compared to healthy controls and to analyze the association between 25-hydroxyvitamin D (25(OH)D) with disease activity and disability. Methods The study includes 1,191 consecutive RA patients (85% women) and 1,019 controls, not on vitamin D supplements, from 22 Italian rheumatology centres. Together with parameters of disease activity, functional impairment, and mean sun exposure time, all patients had serum 25(OH)D measured in a centralized laboratory. Results A total of 55% of RA patients were not taking vitamin D supplements; the proportion of these with vitamin D deficiency (25(OH)D level <20 ng/ml) was 52%. This proportion was similar to that observed in control subjects (58.7%). One third of supplemented patients were still vitamin D deficient. In non-supplemented RA patients 25(OH)D levels were negatively correlated with the Health Assessment Questionnaire Disability Index, Disease Activity Score (DAS28), and Mobility Activities of daily living score. Significantly lower 25(OH)D values were found in patients not in disease remission or responding poorly to treatment, and with the highest Steinbrocker functional state. Body mass index (BMI) and sun exposure time were good predictors of 25(OH)D values (P < 0.001). The association between disease activity or functional scores and 25(OH)D levels remained statistically significant even after adjusting 25(OH)D levels for both BMI and sun exposure time. Conclusions In RA patients vitamin D deficiency is quite common, but similar to that found in control subjects; disease activity and disability scores are inversely related to 25(OH)D levels. PMID:21114806

  6. High Prevalence of Vitamin D Deficiency among Pregnant Saudi Women.

    PubMed

    Al-Faris, Nora A

    2016-02-04

    Vitamin D deficiency has emerged as a public health problem worldwide due to its important role in health and disease. The present work is intended to examine prevalence of vitamin D deficiency among pregnant Saudi women and related risk factors. A cross-sectional study was carried out at King Fahad Medical City in Riyadh, Saudi Arabia. Serum 25-hydroxy vitamin D (25(OH)D) was measured by enzyme-linked immunosorbent assay in 160 pregnant women during the first trimester of pregnancy. Socio-demographic, lifestyle and maternal characteristics were collected and vitamin D intake was assessed using a 24-h dietary recall. Weight and height were measured using standardized methods. Vitamin D deficiency (25(OH)D < 50 nmol/L) and insufficiency (25(OH)D = 50-74 nmol/L) were reported in 50% and 43.8% of the study sample, respectively. Median serum 25(OH)D concentration was 49.9 nmol/L. Adequate vitamin D intake (≥600 IU/day) was reported among only 8.1% of pregnant women. Age group, educational level, sun exposure frequency and daytime and daily practice of exercise were significantly associated with vitamin D status. Overall, vitamin D deficiency was common among pregnant Saudi women in Riyadh. Steps should be taken to address the current situation, including increased sunlight exposure, consumption of fatty fish, and vitamin D supplements.

  7. Vitamin D Supplementation during Pregnancy: Double Blind, Randomized Clinical Trial of Safety and Effectiveness

    PubMed Central

    Hollis, Bruce W.; Johnson, Donna; Hulsey, Thomas C.; Ebeling, Myla; Wagner, Carol L.

    2011-01-01

    Background The need, safety and effectiveness of vitamin D supplementation during pregnancy remain controversial. Design In this randomized controlled trial, women with a singleton pregnancy at 12–16 weeks’ gestation received 400, 2000 or 4000 IU vitamin D3/day until delivery. The primary outcome was maternal/neonatal circulating 25(OH)D at delivery, with secondary outcomes 25(OH)D ≥80 nmol/L achieved and 25(OH)D concentration required to achieve maximal 1,25(OH)2D production. Results Of the 494 women enrolled, 350 women continued until delivery: Mean 25(OH)D by group at delivery and 1-month before delivery were significantly different (p<0.0001), and percent who achieved sufficiency was significantly different by group, greatest in 4000 IU group (p<0.0001). The relative risk (RR) for achieving ≥80 nmol/L within one month of delivery was significantly different between 2000 vs. 400 IU (RR 1.52 [CI 1.24–1.86]); 4000 vs. 400 (RR 1.60 [CI 1.32–1.95]), but not between 4000 vs. 2000 (RR 1.06 [CI 0.93–1.19]). Circulating 25(OH)D had a direct influence on circulating 1,25(OH)2D concentrations throughout pregnancy (p<0.0001) with maximal production of 1,25(OH)2D in all strata in the 4000 IU group. There were no differences between groups on any safety measure. Not a single adverse event was attributed to vitamin D supplementation or circulating 25(OH)D levels. Conclusions Vitamin D supplementation of 4,000 IU/day for pregnant women was safe and most effective in achieving sufficiency in all women and their neonates regardless of race while the current estimated average requirement was comparatively ineffective at achieving adequate circulating 25(OH)D, especially in African Americans. PMID:21706518

  8. Toward an Inexpensive Test for Vitamin D Levels in Blood

    DTIC Science & Technology

    2013-10-01

    involved in vitamin D metabolism) was designed. The enzyme was expressed in E. coli and the activity of this enzyme was verified spectrophotometrically ...fractions were collected for dialysis into buffer C. 1.3. Spectrophotometric activity assay for CYP27B1 The hydroxylation of 25(OH)D to 1,25(OH...for required hydroxylation.6-8 So, the rate of 25(OH)D hydroxylation by CYP27B1 can be monitored spectrophotometrically by monitoring the rate of NADPH

  9. The Effects of Fat-soluble Vitamin Administration on Plasma Vitamin Status of Nursing Pigs Differ When Provided by Oral Administration or Injection

    PubMed Central

    Jang, Y. D.; Lindemann, M. D.; Monegue, H. J.; Stuart, R. L.

    2014-01-01

    Four experiments were conducted to investigate the effect of fat-soluble vitamin administration to sows or newborn pigs on plasma vitamin status. In Exp. 1 and 2, a total of 24 and 43 newborn pigs were allotted to control and vitamin treatments (vitamin D3 with variable addition of vitamins A and E) orally or by i.m. injection. In Exp. 3, pigs from Exp. 2 were allotted to 2 treatments (±vitamins D3 and E in drinking water) for 14 d postweaning. In Exp. 4, twenty-four gestating sows were used for 2 treatments (±injection of a vitamin D3/A/E product 2 wk prepartum). In Exp. 1 and 2, when vitamin D3 was administrated orally or by i.m. injection on d 1 of age, pigs had increased plasma 25-hydroxycholecalciferol (25-OH D3) concentration 10 d after administration compared with control pigs (p<0.05). The injectable administration with vitamin D3 and E was able to achieve higher plasma 25-OH D3 (p<0.05) and α-tocopherol (p<0.05) concentrations than oral administration. At weaning, the pigs in the injection group had higher plasma 25-OH D3 concentration than those in the other groups in both studies (p<0.05). In Exp. 3, water supplementation of vitamin D3 and E postweaning increased plasma 25-OH D3 and α-tocopherol concentrations at d 14 postweaning (p<0.01). In Exp. 4, when sows were injected with the vitamin D3 product prepartum, serum 25-OH D3 concentrations of sows at farrowing (p<0.01), and in their progeny at birth (p<0.01) and weaning (p<0.05) were increased. These results demonstrated that fat-soluble vitamin administration to newborn pigs increased plasma 25-OH D3 concentration regardless of administration routes and α-tocopherol concentration by the injectable route, and that water supplementation of vitamin D3 and E to nursery pigs increased plasma 25-OH D3 and α-tocopherol concentrations. Additionally, injecting sows with vitamin D3 prepartum increased 25-OH D3 in sows and their offspring. If continued research demonstrates that the serum levels of 25-OH D

  10. Providing vitamin D to confined sheep by oral supplementation vs ultraviolet irradiation

    SciTech Connect

    Hidiroglou, M.; Karpinski, K.

    1989-03-01

    Serial vitamin D3 (D3) and 25-hydroxyvitamin D3 (25 OH D3) concentrations of plasma were measured in confined, shorn sheep that had either been supplemented with vitamin D3 (50 micrograms/d) or exposed daily to ultraviolet irradiation (UVI). In the sheep administered D3 orally, plasma D3 increased continuously until d 35. This was followed by small fluctuations of the plasma D3 concentrations until a plateau was reached after 56 d of supplementation (.94 ng/ml plasma). Plasma 25 OH D3 concentrations increased continuously and plateaued between d 65 to 75 at about 21 ng/ml plasma. In the UVI sheep, plasma D3 and 25 OH D3 concentrations increased continuously for the first 49 d, then plateaued at 2.03 ng D3 and 29.6 ng 25 OH D3/ml. When a plateau was reached in plasma 25 OH D3 concentrations in both treatment groups, a /sup 3/H-labeled tracer dose of 25 OH D3 was given i.v., and disappearance of the /sup 3/H-labeled 25 OH D3 was followed. The UVI group had a faster decline in specific activities during the first exponential phase but a slower decline during the prolonged terminal elimination phase. These differences are reflected in the intercompartmental transfer rates. Our data indicate that UVI is as effective as oral vitamin D3 supplementation for improving vitamin D status of confined sheep.

  11. Insights on vitamin D's role in cardiovascular disease: investigating the association of 25-hydroxyvitamin D with the dimethylated arginines.

    PubMed

    Abu El Maaty, Mohamed A; Hassanein, Sally I; Hanafi, Rasha S; Gad, Mohamed Z

    2013-01-01

    Accumulating evidence has stipulated a strong correlation between vitamin D (vitD) deficiency and cardiovascular disease (CVD); however, a mechanistic link is missing. This study investigated the association of vitD with endothelial dysfunction parameters. Subjects comprised male patients with verified coronary artery disease (CAD) (n=69) and age- and sex-matched controls (n=20). 25-Hydroxyvitamin D [25(OH)D] was determined using high performance liquid chromatography with ultraviolet detection whereas asymmetric and symmetric dimethylarginine (ADMA and SDMA, respectively) were determined by liquid chromatography-mass spectrometry. Nitric oxide (NO) was determined spectrophotometrically and high-sensitivity C-reactive protein (hs-CRP) was determined using enzyme-linked immunosorbent assay (ELISA). Comparison of mean 25(OH)D concentrations of patients and controls yielded a significant result (p=0.0002). 25(OH)D2 was dominant in patients whereas 25(OH)D3 was dominant in controls (p=0.003 and 0.001, respectively). Comparison of mean ADMA and SDMA concentrations of patients exhibiting normal and suboptimal vitD yielded insignificant results (p=0.692 and 0.998, respectively). Significant results were obtained from the comparison of mean hs-CRP and NO concentrations of patients exhibiting normal and suboptimal vitD (p=0.035 and 0.031, respectively). Results suggest involvement of vitD with the NO system, however not via modulation of the dimethylated arginines. A potential anti-inflammatory activity for vitD is also raised.

  12. Impact of maternal vitamin D status during pregnancy on neonatal vitamin D status.

    PubMed

    El Koumi, Mohamed A; Ali, Yasser F; Abd El Rahman, Rehab N

    2013-01-01

    Maternal vitamin D deficiency is not uncommon. The lack of vitamin D during pregnancy may result in poor fetal growth and altered neonatal development that may persist into later life. Recognition of risk factors and early detection of vitamin D deficiency during pregnancy are important in order to prevent neonatal vitamin D deficiency and related complications. The aim of the current study was to assess the effect of maternal vitamin D status on the neonatal vitamin D stores. A total of 92 pregnant women at the end of the 3rd trimester and their newborns were recruited from Zagazig University Maternity and Children's Hospital, Egypt during the year 2011. Maternal and cord blood samples were taken at the beginning of the third trimester for determination of serum levels of circulating 25-hydroxyvitamin D3 (25(OH) D3) concentration, serum calcium (Ca++), phosphorus (PO4), and alkaline phosphatase (ALP). Compared with pregnant women with adequate vitamin D levels, women deficient in vitamin D had infants with vitamin D deficiency (X±SD 33.44±18.33 nmol/L vs. 55.39±17.37 nmol/L, p=0.01). Maternal and neonatal serum 25(OH)D3 levels showed a positive correlation with serum Ca++ and negative correlation with serum PO4 and ALP. Neonatal 25(OH) D3 was related to maternal third trimester levels (r=0.89, p=0.01). The newborn serum 25(OH)D3 concentrations are reliant on maternal vitamin D status, and the poor maternal vitamin D status may adversely affect neonatal vitamin D status and consequently Ca++ homeostasis.

  13. Vitamin D in HIV-Infected Patients

    PubMed Central

    JE, Lake; JS, Adams

    2013-01-01

    Observational studies have noted very high rates of low 25(OH)D (vitamin D) levels in both the general and HIV-infected populations. In HIV-infected patients, low 25(OH)D levels are likely a combination of both traditional risk factors and HIV- and antiretroviral therapy-specific contributors. Because of this unique risk profile, HIV-infected persons may be at greater risk for low 25(OH)D levels and frank deficiency and/or may respond to standard repletion regimens differently than HIV-uninfected patients. Currently, the optimal repletion and maintenance dosing regimens for HIV-infected patients remain unknown, as do potential benefits of supplementation that may be unique to the HIV-infected population. This paper reviews data published on HIV infection and vitamin D health in adults over the last year. PMID:21647555

  14. Common genetic determinants of vitamin D insufficiency: the sunlight consortium

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: Vitamin D is crucial for maintaining musculoskeletal health. Recently, vitamin D insufficiency has been linked to a number of extraskeletal disorders, including diabetes, cancer, and cardiovascular disease. Determinants of circulating 25-hydroxyvitamin D (25-OH D) include sun exposure an...

  15. Vitamin D inadequacy in pregnancy: biology, outcomes, and interventions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A high prevalence of maternal vitamin D inadequacy during pregnancy and at delivery has been demonstrated in various ethnic populations living at different latitudes. Because placental transfer of 25(OH)D is the major source of vitamin D to the developing human fetus, there is growing concern about ...

  16. Vitamin D and the skin: an ancient friend, revisited.

    PubMed

    Reichrath, Jörg

    2007-07-01

    Most vertebrates need vitamin D to develop and maintain a healthy mineralized skeleton. However, 1,25-dihydroxyvitamin D3 [1,25(OH)(2)D(3)], the biologically active vitamin D metabolite, exerts a multitude of important physiological effects independent from the regulation of calcium and bone metabolism. We know today that the skin has a unique role in the human body's vitamin D endocrine system. It is the only site of vitamin D photosynthesis, and has therefore a central role in obtaining a sufficient vitamin D status. Additionally, the skin has the capacity to synthesize the biologically active vitamin D metabolite 1,25(OH)(2)D(3), and represents an important target tissue for 1,25(OH)(2)D(3). In keratinocytes and other cell types, 1,25(OH)(2)D(3) regulates growth and differentiation. Consequently, vitamin D analogues have been introduced for the treatment of the hyperproliferative skin disease psoriasis. Recently, sebocytes were identified as 1,25(OH)(2)D(3)-responsive target cells, indicating that vitamin D analogues may be effective in the treatment of acne. Other new functions of vitamin D analogues include profound effects on the immune system as well as in various tissues protection against cancer and other diseases, including autoimmune and infectious diseases. It can be speculated that the investigation of biological effects of vitamin D analogues will lead to new therapeutic applications that, besides cancer prevention, may include the prevention and treatment of infectious as well as of inflammatory skin diseases. Additionally, it can be assumed that dermatological recommendations on sun protection and health campaigns for skin cancer prevention will have to be re-evaluated to guarantee a sufficient vitamin D status.

  17. [Guidelines for vitamin D prescription in dialysis patients].

    PubMed

    Jean, Guillaume; Lafage-Proust, Marie-Hélène; Massy, Ziad A; Drüeke, Tilman B

    2009-11-01

    The vitamin D hormonal system is involved in the regulation of more than 800 genes. Vitamin D deficiency, which is evaluated on the basis of the serum level of 25-hydroxycholecalciferol (25[OH]D), is frequently observed in the general population, particularly in patients with chronic kidney disease (CKD). Vitamin D deficiency is associated with an increased risk of falls and fracture and also with diabetes, malignancies, autoimmune diseases, depression and mortality. Furthermore, CKD is accompanied by a decrease in the renal production of 1,25 dihydroxycholecalciferol (1,25[OH](2)D). Such deficiencies have also been implicated in the pathophysiology of secondary hyperparathyroidism. Currently, vitamin D supplementation is not recommended in stage 5 CKD. However, since there is also significant extra-renal production of 1,25(OH)(2)D this would appear to be in favour of vitamin D treatment. We describe the disturbances of vitamin D metabolism occurring in CKD and discuss the advantages and the potential toxicity risk of vitamin D supplementation as well as the optimal serum 25[OH]D level. We then present the pharmacological properties of the various medicinal forms of vitamin D derivates and suggest therapeutic guidelines for supplementation with 25(OH)D(3) or cholecalciferol. We also examine existing guidelines for the administration of active 1-alpha-hydroxylated vitamin D. Despite the absence of strong scientific support by randomized controlled intervention studies, vitamin D supplementation should be considered in patients with CKD stages 4-5D having vitamin D insufficiency or deficiency, for the prevention of secondary hyperparathyroidism and for other potential benefits owing to its pleiotropic effects.

  18. Mechanisms involved in vitamin D mediated intestinal calcium absorption and in non-classical actions of vitamin D.

    PubMed

    Christakos, Sylvia; Dhawan, Puneet; Ajibade, Dare; Benn, Bryan S; Feng, Jingjing; Joshi, Sneha S

    2010-07-01

    Recent studies in our laboratory using calbindin-D9k null mutant mice as well as mice lacking the 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) inducible epithelial calcium channel TRPV6 provide evidence for calbindin-D9k and TRPV6 independent regulation of active intestinal calcium absorption. These findings suggest that in the knock out (KO) mice there is compensation by another calcium channel or protein and that other novel factors are involved in 1,25(OH)2D3 mediated active intestinal calcium absorption. In addition, 1,25(OH)2D3 mediated paracellular transport of calcium may have contributed to the normalization of serum calcium in the null mutant mice. 1,25(OH)2D3 downregulates cadherin-17 and upregulates claudin-2 and claudin-12 in the intestine, suggesting that 1,25(OH)2D3, by regulating these epithelial cell junction proteins, can route calcium through the paracellular path. With regard to non-classical actions, 1,25(OH)2D3 has been reported to inhibit the proliferation of a number of malignant cells and to regulate adaptive as well as innate immunity. This article will review new developments related to the function and regulation of vitamin D target proteins in classical and non-classical vitamin D target tissues that have provided novel insight into mechanisms of vitamin D action.

  19. Vitamin D and rheumatoid arthritis

    PubMed Central

    Athanassiou, Panagiotis; Lyraki, Aikaterini; Raftakis, Ioannis; Antoniadis, Christodoulos

    2012-01-01

    Objectives: Vitamin D deficiency has been implicated in the pathogenesis of autoimmune diseases, such as diabetes mellitus type 1 and multiple sclerosis. Reduced vitamin D intake has been linked to increased susceptibility to the development of rheumatoid arthritis (RA) and vitamin D deficiency has been found to be associated with disease activity in patients with RA. The objective was to evaluate vitamin D status in patients with RA and to assess the relationship between vitamin D levels and disease activity. Methods: In a cohort of 44 patients with RA, 25-hydroxyvitamin D3 [25(OH)D3] levels, parathyroid hormone levels, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) were measured. Disease activity was evaluated by calculating the 28-joint Disease Activity Score (DAS28). A control group (n = 44), matched for age and sex, was evaluated as well. Results: In the cohort of 44 patients with RA 25(OH)D3 levels were found to be low compared with the control group, 25(OH)D3 being 15.26 ± 1.07 ng/ml [mean ± standard error of the mean (SEM)] and 25.8 ± 1.6 ng/ml in the patient and control group respectively (Student’s t test, p < 0.001). Parathyroid hormone levels were 71.08 ± 7.02 pg/ml (mean ± SEM) (normal values 10.0–65.0 pg/ml), CRP 7.6 ± 1.57 mg/litre (mean ± SEM) (normal values < 3 mg/litre) and ESR was 38.0 ± 4.6 mm/h (mean ± SEM) in the group of patients with RA. Levels of 25(OH)D3 were found to be negatively correlated to the DAS28, the correlation coefficient being −0.084. Levels of 25(OH)D3 were also found to be negatively correlated to CRP and ESR, the correlation coefficient being –0.115 and −0.18, respectively. Conclusion: It appears that vitamin D deficiency is highly prevalent in patients with RA, and that vitamin D deficiency may be linked to disease severity in RA. As vitamin D deficiency has been linked to diffuse musculoskeletal pain, these results have therapeutic implications. Vitamin D supplementation may be needed

  20. Ultraviolet index: a light in atopic dermatitis and vitamin D research?*

    PubMed Central

    Mesquita, Kleyton de Carvalho; Igreja, Ana Carolina de Souza Machado; Costa, Izelda Maria Carvalho

    2016-01-01

    BACKGROUND: The role played by vitamin D in atopic dermatitis is controversial and has been the focus of many studies. The ultraviolet index has not been considered in this type of research. OBJECTIVES: The objectives of the study were to assess 25-hydroxy vitamin D [25(OH)D] serum level in atopic dermatitis patients and control group, to investigate the association between atopic dermatitis clinical severity (using the SCORing Atopic Dermatitis index - SCORAD) and 25(OH)D serum levels, and to evaluate the independent predictors, including Ultraviolet index, SCORAD and 25(OH)D. METHODS: We conducted a cross-sectional study of 106 atopic dermatitis patients. A control group was matched with a subsample of 54 participants with atopic dermatitis. SCORAD index, laboratory tests, and local Ultraviolet index were assessed. RESULTS: The atopic dermatitis patients had serum 25(OH)D levels and mean UVI significantly higher than the control group. Immunoglobulin E and Ultraviolet index were associated with the SCORAD index. Skin type, age and Ultraviolet index were independent predictors of 25(OH)D. CONCLUSIONS: Although statistically significant, the different levels of 25(OH)D between the paired groups may be attributed to the higher mean Ultraviolet index in atopic dermatitis patients. Since Ultraviolet index is an independent predictor of SCORAD index and of 25(OH)D level, it may work as a confounding factor in studies involving atopic dermatitis and 25(OH)D and must be considered in this kind of research. PMID:26982776

  1. Circulating Vitamin D, Vitamin D-related genetic variation, and risk of fatal prostate cancer in the National Cancer Institute Breast and Prostate Cancer Cohort Consortium

    PubMed Central

    Shui, Irene M; Mondul, Alison M.; Lindström, Sara; Tsilidis, Konstantinos K.; Travis, Ruth C.; Gerke, Travis; Albanes, Demetrius; Mucci, Lorelei A; Giovannucci, Edward; Kraft, Peter

    2015-01-01

    Background Evidence from animal and cell line experimental studies support a beneficial role for vitamin D in prostate cancer (PCa). While the results from human studies have been mainly null for overall PCa risk, there may be a benefit for survival. We assessed the associations of circulating 25-hydroxyvitamin D [25(OH)D] and common variation in key vitamin D-related genes with fatal PCa. Methods In a large cohort consortium, we identified 518 fatal cases and 2986 controls with 25(OH)D data. Genotyping information for 91 single nucleotide polymorphisms (SNPs) in 7 vitamin D-related genes (VDR, GC, CYP27A1, CYP27B1, CYP24A1, CYP2R1, RXRA) was available for 496 fatal cases and 3577 controls. We used unconditional logistic regression to calculate odd ratios (OR) and 95% confidence intervals (CI) for the associations of 25(OH)D and SNPs with fatal PCa. We also tested for 25(OH)D-SNP interactions among 264 fatal cases and 1169 controls. Results We observed no statistically significant relationship between 25(OH)D and fatal PCa [OR(95% CI)extreme quartiles=0.86(0.65-1.14); p-trend=0.22] or the main effects of the SNPs and fatal PCa. There was suggestive evidence that associations of several SNPs (including 5 related to circulating 25(OH)D) with fatal PCa were modified by 25(OH)D. Individually these associations would not remain significant after considering multiple testing; however the p-value for the set-based test for CYP2R1 was 0.002. Conclusions In our study, we did not observe statistically significant associations for either 25(OH)D or vitamin D-related SNPs with fatal PCa. Effect modification of 25(OH)D associations by biologically plausible genetic variation may deserve further exploration. PMID:25731953

  2. Low maternal serum vitamin D during pregnancy and the risk for postpartum depression symptoms.

    PubMed

    Robinson, Monique; Whitehouse, Andrew J O; Newnham, John P; Gorman, Shelley; Jacoby, Peter; Holt, Barbara J; Serralha, Michael; Tearne, Jessica E; Holt, Pat G; Hart, Prue H; Kusel, Merci M H

    2014-06-01

    Pregnancy is a time of vulnerability for vitamin D insufficiency, and there is an emerging literature associating low levels of 25(OH)-vitamin D with depressive symptoms. However, the link between 25(OH)-vitamin D status in pregnancy and altered risk of postnatal depressive symptoms has not been examined. We hypothesise that low levels of 25(OH)-vitamin D in maternal serum during pregnancy will be associated with a higher incidence of postpartum depressive symptoms. We prospectively collected sera at 18 weeks gestation from 796 pregnant women in Perth (1989-1992) who were enrolled in the Western Australian Pregnancy Cohort (Raine) Study and measured levels of 25(OH)-vitamin D. Women reported postnatal depressive symptoms at 3 days post-delivery. Women in the lowest quartile for 25(OH)-vitamin D status were more likely to report a higher level of postnatal depression symptoms than women who were in the highest quartile for vitamin D, even after accounting for a range of confounding variables including season of birth, body mass index and sociodemographic factors. Low vitamin D during pregnancy is a risk factor for the development of postpartum depression symptoms.

  3. Multiple Sclerosis and Vitamin D

    MedlinePlus

    ... mL) levels. Every participant received 1,000 IU vitamin D2, a synthetic form of vitamin D derived from ... identical pill containing 6,000 IU of additional vitamin D2. Vitamin D levels were checked during the study ...

  4. The association of 25(OH)D with blood pressure, pulse pressure and carotid-radial pulse wave velocity in African women.

    PubMed

    Kruger, Iolanthé M; Kruger, Marlena C; Doak, Colleen M; Schutte, Aletta E; Huisman, Hugo W; Van Rooyen, Johannes M; Schutte, Rudolph; Malan, Leoné; Malan, Nicolaas T; Fourie, Carla M T; Kruger, Annamarie

    2013-01-01

    High susceptibility of the African population to develop cardiovascular disease obliges us to investigate possible contributing risk factors. Our aim was to determine whether low 25(OH)D status is associated with increased blood pressure and carotid-radial pulse wave velocity in black South African women. We studied 291 urban women (mean age: 57.56±9.00 yrs.). 25(OH)D status was determined by serum 25(OH)D levels. Women were stratified into sufficient (>30 ng/ml), and insufficient/deficient (<30 ng/ml) groups. Cardiovascular variables were compared between groups. Women with low 25(OH)D levels had significantly higher SBP (150.8±27.1 vs. 137.6±21.0), DBP (94.7±14.5 vs. 89.3±12.3) and PP (53.15(50.7;55.7) vs. 46.3(29.4;84.6)) compared to women with sufficient levels. No significant difference was observed with regards to c-rPWV. ANCOVA analyses still revealed significant differences between the two groups with regards to SBP, DBP as well as PP. Partial correlations revealed significant inverse association between SBP and 25(OH)D (p = .04;r = -.12). Women with low 25(OH)D levels were ∼2 times more likely to have high SBP (95% CI: 3.23;1.05). To conclude, women with deficient/insufficient 25(OH)D had significantly higher SBP compared to women with a sufficient 25(OH) status.

  5. 1,25(OH)₂D₃-enhanced hypercalciuria in genetic hypercalciuric stone-forming rats fed a low-calcium diet.

    PubMed

    Frick, Kevin K; Asplin, John R; Krieger, Nancy S; Culbertson, Christopher D; Asplin, Daniel M; Bushinsky, David A

    2013-10-15

    The inbred genetic hypercalciuric stone-forming (GHS) rats exhibit many features of human idiopathic hypercalciuria and have elevated levels of vitamin D receptors (VDR) in calcium (Ca)-transporting organs. On a normal-Ca diet, 1,25(OH)2D3 (1,25D) increases urine (U) Ca to a greater extent in GHS than in controls [Sprague-Dawley (SD)]. The additional UCa may result from an increase in intestinal Ca absorption and/or bone resorption. To determine the source, we asked whether 1,25D would increase UCa in GHS fed a low-Ca (0.02%) diet (LCD). With 1,25D, UCa in SD increased from 1.2 ± 0.1 to 9.3 ± 0.9 mg/day and increased more in GHS from 4.7 ± 0.3 to 21.5 ± 0.9 mg/day (P < 0.001). In GHS rats on LCD with or without 1,25D, UCa far exceeded daily Ca intake (2.6 mg/day). While the greater excess in UCa in GHS rats must be derived from bone mineral, there may also be a 1,25D-mediated decrease in renal tubular Ca reabsorption. RNA expression of the components of renal Ca transport indicated that 1,25D administration results in a suppression of klotho, an activator of the renal Ca reabsorption channel TRPV5, in both SD and GHS rats. This fall in klotho would decrease tubular reabsorption of the 1,25D-induced bone Ca release. Thus, the greater increase in UCa with 1,25D in GHS fed LCD strongly suggests that the additional UCa results from an increase in bone resorption, likely due to the increased number of VDR in the GHS rat bone cells, with a possible component of decreased renal tubular calcium reabsorption.

  6. [The vitamin D endocrine system].

    PubMed

    Castro, Luiz Claudio Gonçalves de

    2011-11-01

    The vitamin D endocrine system comprises a group of 7-dehydrocholesterol-derived secosteroid molecules, including its active metabolite 1,25-dihydroxy-vitamin D (1,25(OH)(2)D), its precursors and other metabolites, its binding protein (DBP) and nuclear receptor (VDR), as well as cytochrome P450 complex enzymes participating in activation and inactivation pathways of those molecules. The biologic effects of 1,25(OH)(2)D are mediated by VDR, a ligand-activated transcription factor which is a member of the nuclear receptors family, spread in almost all human cells. In addition to its classic role in the regulation of calcium metabolism and bone health, evidence suggests that 1,25(OH)(2)D directly or indirectly modulates about 3% of the human genome, participating in the regulation of chief functions of systemic homeostasis, such as cell growth, differentiation and apoptosis, regulation of immune, cardiovascular and musculoskeletal systems, and insulin metabolism. Given the critical influence of the vitamin D endocrine system in many processes of systemic metabolic equilibrium, the laboratory assays available for the evaluation of this system have to present high accuracy and reproducibility, enabling the establishment of cutoff points that, beyond being consensually accepted, reliably express the vitamin D status of the organism, and the respective clinical-metabolic impacts on the global health of the individual.

  7. Serum Vitamin D levels in patients with chronic kidney disease

    PubMed Central

    Rozita, Mohd; Noorul Afidza, Mohamad; Ruslinda, Mustafar; Cader, Rizna; Halim, A. Gafor; Kong, Chiew Tong Norella; Nor Azmi, Kamaruddin; Shah, Shamsul Azhar

    2013-01-01

    Introduction: Hypovitaminosis D is reported to be associated with several medical complications. Recent studies have reported a high worldwide prevalence of Vitamin D deficiency in the general population (up to 80 %). This is even higher in patients with chronic kidney disease (CKD) and increases with advancing stages of CKD. Objectives: To determine the difference in serum Vitamin D [25-hydroxyvitamin D, 25(OH) D] levels between CKD patients and normal healthy population. Materials and Methods: A prospective cross-sectional study involving 50 normal volunteers (control) and 50 patients with CKD stages 2-4. Their demographic profiles were recorded and blood samples taken for serum 25(OH) D, intact parathyroid hormone (iPTH) and other routine blood tests. Results: All subjects regardless of renal status had hypovitaminosis D (< 30ng/mL). The mean serum 25(OH) D were comparable in the control and CKD groups (15.3 ± 4.2 ng/mL vs 16.1 ± 6.2 ng/mL, p = NS). However, within the Vitamin D deficient group, the CKD group had lower levels of serum 25(OH) D [12.6(3.7) ng/mL vs 11.2(6.5) ng/mL, p = 0.039]. Female gender [OR 22.553; CI 95 % (2.16-235.48); p = 0.009] and diabetic status [OR 6.456; CI 95 % (1.144-36.433); p = 0.035] were independent predictors for 25(OH) D deficiency. Conclusions: Vitamin D insufficiency and vitamin D deficiency are indeed prevalent and under-recognized. Although the vitamin D levels among the study subjects and their control are equally low, the CKD group had severe degree of vitamin D deficiency. Diabetic status and female gender were independent predictors of low serum 25(OH)D. PMID:26933400

  8. Vitamin D in adolescents: Are current recommendations enough?

    PubMed

    Smith, Taryn J; Lanham-New, Susan A; Hart, Kathryn H

    2017-02-16

    Vitamin D is essential for bone development during adolescence and low vitamin D status during this critical period of growth may impact bone mineralization, potentially reducing peak bone mass and consequently increasing the risk of osteoporosis in adulthood. Therefore, the high prevalence of vitamin D inadequacy and deficiency in adolescent populations is of great concern. However, there is currently a lack of consensus on the 25-hydroxyvitamin D [25(OH)D] concentration, the widely accepted biomarker of vitamin D status, that defines adequacy, and the vitamin D intake requirements to maintain various 25(OH)D thresholds are not well established. While the current intake recommendations of 10-15μg/day may be sufficient to prevent vitamin D deficiency (25(OH)D<25-30nmol/l), greater intakes may be needed to achieve the higher threshold levels proposed to represent adequacy (25(OH)D>50nmol/l). This review will address these concerns and consider if the current dietary recommendations for vitamin D in adolescents are sufficient.

  9. Vitamin D Attenuates Left Atrial Volume Changes in African American Males with Obesity and Prediabetes.

    PubMed

    Chacko, Satish Jacob; Pauwaa, Sunil; Barengolts, Elena; Ciubotaru, Irina; Kansal, Mayank M

    2016-05-01

    Vitamin D deficiency is common among African Americans in the United States and is associated with increased cardiovascular disease risk. In this study, prediabetic African American males who were found to be vitamin D-deficient were randomized to vitamin D supplementation and assessed for changes in left atrial (LA) volume. Prediabetic African American males who were vitamin D-deficient (25(OH)D: 5.0-29 ng/mL) were randomized to high-dose ergocalciferol or placebo. Echocardiography was performed at baseline and at 1 year. Ejection fraction (EF), septal and posterior wall thickness, LA area, LA length, LA volume, E, A, septal and lateral e' and a', deceleration time, and isovolumetric relaxation time were collected. Eighty-one of 158 (51%) subjects received vitamin D2 . Baseline characteristics were similar among both groups. In the placebo group, left atrial volume significantly increased on follow-up (LA volume increased 6.3 mL, P = 0.0025). Compared with placebo group, the treatment group with ergocalciferol had attenuated increases in left atrial volume (LA volume increased 2.6 mL, P = 0.29). Changes in left atrial volume persisted when indexed to body surface area. There was no significant difference in other diastolic parameters and blood pressure between groups. In conclusion, vitamin D-deficient prediabetic African American males who were treated with high-dose vitamin D2 were found to have attenuated increases in left atrial volume compared with controls over 12-month follow-up.

  10. Development and Validation of a Vitamin D Status Prediction Model in Danish Pregnant Women: A Study of the Danish National Birth Cohort

    PubMed Central

    Bjørn Jensen, Camilla; Thorne-Lyman, Andrew L.; Vadgård Hansen, Linda; Strøm, Marin; Odgaard Nielsen, Nina; Cohen, Arieh; Olsen, Sjurdur Frodi

    2013-01-01

    Vitamin D has been hypothesized to reduce risk of pregnancy complications such as preeclampsia, gestational diabetes mellitus, and preterm delivery. However, many of these outcomes are rare and require a large sample size to study, representing a challenge for cohorts with a limited number of preserved samples. The aims of this study were to (1) identify predictors of serum 25-hydroxy-vitamin D (25(OH)D) among pregnant women in a subsample (N = 1494) of the Danish National Birth Cohort (DNBC) and (2) develop and validate a score predicting 25(OH)D-status in order to explore associations between vitamin D and maternal and offspring health outcomes in the DNBC. In our study sample, 42.3% of the population had deficient levels of vitamin D (<50 nmol/L 25(OH)D) and average levels of 25(OH)D-status were 56.7(s.d. 24.6) nmol/L. A prediction model consisting of intake of vitamin D from diet and supplements, outdoor physical activity, tanning bed use, smoking, and month of blood draw explained 40.1% of the variance in 25(OH)D and mean measured 25(OH)D-level increased linearly by decile of predicted 25(OH)D-score. In total 32.2% of the women were placed in the same quintile by both measured and predicted 25(OH)D-values and 69.9% were placed in the same or adjacent quintile by both methods. Cohen's weighted kappa coefficient (Κ = 0.3) reflected fair agreement between measured 25(OH)D-levels and predicted 25(OH)D-score. These results are comparable to other settings in which vitamin D scores have shown similar associations with disease outcomes as measured 25(OH)D-levels. Our findings suggest that predicted 25(OH)D-scores may be a useful alternative to measured 25(OH)D for examining associations between vitamin D and disease outcomes in the DNBC cohort, but cannot substitute for measured 25(OH)D-levels for estimates of prevalence. PMID:23326380

  11. Vitamin D deficiency is associated with insulin resistance in nondiabetics and reduced insulin production in type 2 diabetics.

    PubMed

    Esteghamati, A; Aryan, Z; Esteghamati, Ar; Nakhjavani, M

    2015-04-01

    It is not known whether the association of serum 25-hydroxyvitamin D [25(OH)D] with glycemic measurements of individuals without diabetes is similar to those with diabetes or not. This study is aimed to investigate the association of serum 25(OH)D with glycemic markers of diabetics, nondiabetics, and prediabetics. A case-control study was conducted on age and sex matched 1,195 patients with type 2 DM, 121 prediabetics, and 209 healthy controls. Anthropometric variables, lipid profile, glycemic measurements, and serum 25(OH)D levels were recorded. Serum insulin and C-peptide levels were also measured. All glycemic measurements were compared between diabetics and nondiabetics and prediabetics at different vitamin D status. Patients with DM had lower serum 25(OH)D compared to prediabetics and healthy controls. Endogenous insulin production in response to food intake and in fasting was significantly lower in vitamin D deficient patients with DM compared to those with serum 25(OH)D>40 ng/ml. Diabetic women with serum 25(OH)D<20 ng/ml had lower beta cell function as estimated by lower HOMA-B compared to their counterparts with serum 25(OH)D>40 ng/ml. Healthy individuals with serum 25(OH)D<20 ng/ml had signs of insulin resistance as estimated by significant increase of HOMA-IR, HbA1c, and fasting plasma glucose (FPG). In addition, we found that serum 25(OH)D was inversely associated with insulin resistance. Vitamin D deficiency is associated with insulin resistance in nondiabetics, which is independent of obesity. Furthermore, vitamin D deficiency is associated with reduced insulin production in type 2 diabetics, which was mainly observed in men. Accordingly, a gender disparity also exists in association of serum 25(OH)D with glycemic measurements.

  12. Vitamin D Status during Pregnancy in a Multi-Ethnic Population-Representative Swedish Cohort

    PubMed Central

    Bärebring, Linnea; Schoenmakers, Inez; Glantz, Anna; Hulthén, Lena; Jagner, Åse; Ellis, Joy; Bärebring, Mattias; Bullarbo, Maria; Augustin, Hanna

    2016-01-01

    There is currently little information on changes in vitamin D status during pregnancy and its predictors. The aim was to study the determinants of change in vitamin D status during pregnancy and of vitamin D deficiency (<30 nmol/L) in early pregnancy. Blood was drawn in the first (T1) and third trimester (T3). Serum 25-hydroxyvitamin D (25(OH)D) (N = 1985) was analysed by liquid chromatography tandem-mass spectrometry. Season-corrected 25(OH)D was calculated by fitting cosine functions to the data. Mean (standard deviation) 25(OH)D was 64.5(24.5) nmol/L at T1 and 74.6(34.4) at T3. Mean age was 31.3(4.9) years, mean body mass index (BMI) was 24.5(4.2) kg/m2 and 74% of the women were born in Sweden. Vitamin D deficiency was common among women born in Africa (51%) and Asia (46%) and prevalent in 10% of the whole cohort. Determinants of vitamin D deficiency at T1 were of non-North European origin, and had less sun exposure, lower vitamin D intake and lower age. Season-corrected 25(OH)D increased by 11(23) nmol/L from T1 to T3. The determinants of season-corrected change in 25(OH)D were origin, sun-seeking behaviour, clothing style, dietary vitamin D intake, vitamin D supplementation and recent travel <35° N. In conclusion, season-corrected 25(OH)D concentration increased during pregnancy and depended partly on lifestyle factors. The overall prevalence of vitamin D deficiency was low but common among women born in Africa and Asia. Among them, the determinants of both vitamin D deficiency and change in season-corrected vitamin D status were fewer, indicating a smaller effect of sun exposure. PMID:27782070

  13. Analytical considerations for the biochemical assessment of vitamin D status

    PubMed Central

    Couchman, Lewis; Moniz, Cajetan F

    2017-01-01

    The most widely used and clinically accepted biochemical marker for assessing vitamin D status is the total serum 25-hydroxyvitamin D [25(OH)D] concentration. Despite the analysis of 25(OH)D dating back to the early 1970s, modern analytical techniques still exhibit significant interassay variability due to varying concentrations of other related vitamin D metabolites and sample-to-sample matrix differences. It is important for clinicians requesting 25(OH)D analyses to understand these issues and limitations, and where necessary to confront laboratories for details of analytical methods used. The availability of reference measurement procedures for 25(OH)D based on liquid chromatography and tandem mass spectrometry, whilst not intended for routine clinical sample analysis, should be utilized to improve assay harmonization and reduce interlaboratory variability. Laboratories should also be forthcoming with details of subscriptions to external quality assessment schemes and assay traceability. As well as discussing the reasons for ongoing assay variability for 25(OH)D, this short review will also briefly discuss other assays related to the assessment of vitamin D status, including parathyroid hormone, 24,25-dihydroxyvitamin D, 1,25-dihydroxyvitamin D and vitamin D binding proteins. PMID:28382113

  14. Vitamin D status is associated with grip strength in centenarians.

    PubMed

    Haslam, Alyson; Johnson, Mary Ann; Hausman, Dorothy B; Cress, M Elaine; Houston, Denise K; Davey, Adam; Poon, Leonard W

    2014-01-01

    Low serum concentrations of 25-hydroxyvitamin D (25(OH)D) have been associated with poor physical function in older adults, but few, if any, studies have examined this relationship in the very old. Therefore, the purpose of this study is to examine this relationship in the very old. Serum 25(OH)D concentrations were obtained from 194 centenarians and near centenarians (98 years and older). The associations between 25(OH)D concentrations and measures of physical function were evaluated with unadjusted and adjusted regression models. We found that 35% of centenarians had 25(OH)D concentrations less than 50 nmol/L. Adjusted mean grip strength was lower for centenarians with 25(OH)D concentrations less than 75 nmol/L than for centenarians with higher concentrations (P<0.05). However, there were no differences in the Georgia Centenarian Study (GCS) Composite Scale, a global measure of physical function, between those with higher and lower 25(OH)D concentrations. We conclude that low 25(OH)D concentrations are associated with poor grip strength, but not GCS Composite Scale, in the very old. Considering the high burden of poor physical function in older adults, understanding the relationship between vitamin D and different measures of physical function, including strength, becomes increasingly important.

  15. Isolated Vitamin D Deficiency Is Not Associated with Nonthyroidal Illness Syndrome, but with Thyroid Autoimmunity

    PubMed Central

    Sayki Arslan, Muyesser; Topaloglu, Oya; Ucan, Bekir; Karakose, Melia; Karbek, Basak; Tutal, Esra; Caliskan, Mustafa; Ginis, Zeynep; Cakal, Erman; Sahin, Mustafa; Ozbek, Mustafa; Delibasi, Tuncay

    2015-01-01

    Aim. This study aimed to compare thyroid functions, thyroid autoantibodies, and the existence of nonthyroidal illness syndrome (NTIS) according to vitamin D level. Materials and Methods. The study included age- and BMI-matched healthy volunteers with and without vitamin D deficiency. In addition, the nonthyroidal illness syndrome status was evaluated. Results. Anti-TPO positivity was significantly more common in those with severe and moderate vitamin D deficiency, as compared to those with a normal 25(OH)D level. Furthermore, TSH levels were significantly lower in those with severe and moderate vitamin D deficiency than in those with a normal 25(OH)D level. In addition, there was a significant weak inverse correlation between anti-TPO positivity and the 25(OH)D level and a positive correlation between the TSH level and 25(OH)D level. Only 1 thyroid function test result was compatible with NTIS among the participants with moderate vitamin D deficiency; therefore the difference was not significant. Conclusions. The prevalence of thyroid autoantibody positivity was higher in those with severe and moderate vitamin D deficiency than in those with a normal 25(OH)D level. Additional large-scale studies must be conducted to determine if vitamin D deficiency plays a causal role in the pathogenesis of Hashimoto's thyroiditis and NTIS. PMID:25654127

  16. Factors Affecting 25-Hydroxyvitamin D Concentration in Response to Vitamin D Supplementation

    PubMed Central

    Mazahery, Hajar; von Hurst, Pamela R.

    2015-01-01

    Sun exposure is the main source of vitamin D. Due to many lifestyle risk factors vitamin D deficiency/insufficiency is becoming a worldwide health problem. Low 25(OH)D concentration is associated with adverse musculoskeletal and non-musculoskeletal health outcomes. Vitamin D supplementation is currently the best approach to treat deficiency and to maintain adequacy. In response to a given dose of vitamin D, the effect on 25(OH)D concentration differs between individuals, and it is imperative that factors affecting this response be identified. For this review, a comprehensive literature search was conducted to identify those factors and to explore their significance in relation to circulating 25(OH)D response to vitamin D supplementation. The effect of several demographic/biological factors such as baseline 25(OH)D, aging, body mass index(BMI)/body fat percentage, ethnicity, calcium intake, genetics, oestrogen use, dietary fat content and composition, and some diseases and medications has been addressed. Furthermore, strategies employed by researchers or health care providers (type, dose and duration of vitamin D supplementation) and environment (season) are other contributing factors. With the exception of baseline 25(OH)D, BMI/body fat percentage, dose and type of vitamin D, the relative importance of other factors and the mechanisms by which these factors may affect the response remains to be determined. PMID:26121531

  17. 1α,25(OH)2D3 Suppresses the Migration of Ovarian Cancer SKOV-3 Cells through the Inhibition of Epithelial–Mesenchymal Transition

    PubMed Central

    Hou, Yong-Feng; Gao, Si-Hai; Wang, Ping; Zhang, He-Mei; Liu, Li-Zhi; Ye, Meng-Xuan; Zhou, Guang-Ming; Zhang, Zeng-Li; Li, Bing-Yan

    2016-01-01

    Ovarian cancer is the most lethal gynecological malignancy due to its high metastatic ability. Epithelial-mesenchymal transition (EMT) is essential during both follicular rupture and epithelium regeneration. However, it may also accelerate the progression of ovarian carcinomas. Experimental studies have found that 1α,25-dihydroxyvitamin-D3 [1α,25(OH)2D3] can inhibit the proliferation of ovarian cancer cells. In this study, we investigated whether 1α,25(OH)2D3 could inhibit the migration of ovarian cancer cells via regulating EMT. We established a model of transient transforming growth factor-β1(TGF-β1)-induced EMT in human ovarian adenocarcinoma cell line SKOV-3 cells. Results showed that, compared with control, 1α,25(OH)2D3 not only inhibited the migration and the invasion of SKOV-3 cells, but also promoted the acquisition of an epithelial phenotype of SKOV-3 cells treated with TGF-β1. We discovered that 1α,25(OH)2D3 increased the expression of epithelial marker E-cadherin and decreased the level of mesenchymal marker, Vimentin, which was associated with the elevated expression of VDR. Moreover, 1α,25(OH)2D3 reduced the expression level of transcription factors of EMT, such as slug, snail, and β-catenin. These results indicate that 1α,25(OH)2D3 suppresses the migration and invasion of ovarian cancer cells by inhibiting EMT, implying that 1α,25(OH)2D3 might be a potential therapeutic agent for the treatment of ovarian cancer. PMID:27548154

  18. Vitamin D and cardiovascular disease.

    PubMed

    Nemerovski, Carrie W; Dorsch, Michael P; Simpson, Robert U; Bone, Henry G; Aaronson, Keith D; Bleske, Barry E

    2009-06-01

    The hormonal derivative of vitamin D, 1,25-dihydroxyvitamin D (1,25[OH](2)D) or calcitriol, has been implicated in many physiologic processes beyond calcium and phosphorus homeostasis, and likely plays a role in several chronic disease states, in particular, cardiovascular disease. Experimental data suggest that 1,25(OH)(2)D affects cardiac muscle directly, controls parathyroid hormone secretion, regulates the renin-angiotensin-aldosterone system, and modulates the immune system. Because of these biologic effects, vitamin D deficiency has been associated with hypertension, several types of vascular diseases, and heart failure. We conducted a MEDLINE search of the English-language literature (1950-2008) to identify studies that examined these relationships; additional citations were obtained from the articles retrieved from the literature search. Treatment with vitamin D lowered blood pressure in patients with hypertension and modified the cytokine profile in patients with heart failure. Measurement of serum 25-hydroxyvitamin D concentration usually provides the best assessment of an individual's vitamin D status. Serum levels below 20 ng/ml represent vitamin D deficiency, and levels above 30 ng/ml are considered optimal. Although the observational data linking vitamin D status to cardiovascular disease appear robust, vitamin D supplementation is not recommended as routine treatment for heart disease until definitive prospective, randomized trials can be carried out to assess its effects. However, such supplementation is often appropriate for other reasons and may be beneficial to cardiovascular health in certain patients.

  19. Circulating pro-inflammatory cytokines are elevated and peak power output correlates with 25-hydroxyvitamin D in vitamin D insufficient adults.

    PubMed

    Barker, Tyler; Martins, Thomas B; Hill, Harry R; Kjeldsberg, Carl R; Dixon, Brian M; Schneider, Erik D; Henriksen, Vanessa T; Weaver, Lindell K

    2013-06-01

    The purpose of this study was to identify circulating cytokines, skeletal muscle strength, and peak power output in young adults with contrasting serum 25-hydroxyvitamin D (25(OH)D) concentrations. Serum 25(OH)D, inflammatory cytokines, muscle strength, and peak power output were, therefore, measured in young adults (25-42 years). Data were collected during the winter to avoid the seasonal influence on serum 25(OH)D. After serum 25(OH)D concentration measurements, subjects were separated into one of two groups: (1) vitamin D insufficient [serum 25(OH)D ≤32 ng/mL, n = 14], or (2) vitamin D sufficient [serum 25(OH)D >32 ng/mL, n = 14]. Following group allocation, serum 25(OH)D concentrations were significantly (p < 0.05) lower and pro-inflammatory cytokines [interleukin (IL)-2, IL-1β, tumor necrosis factor-α, and interferon-γ] were significantly (all p < 0.05) greater in vitamin D insufficient adults. An anti-inflammatory cytokine (i.e., IL-10; p > 0.05), peak isometric forces (p > 0.05), and peak power outputs (p > 0.05) were not significantly different between vitamin D groups. However, peak power outputs correlated with serum 25(OH)D concentrations in vitamin D insufficient (r = 0.55, p < 0.05) but not in vitamin D sufficient adults (r = -0.27, p = 0.36). Based on these data, we conclude that vitamin D insufficiency, in part, could result in pro-inflammatory stress without altering muscular strength or function in young adults. Future research investigating the causality of the correlation between low-serum 25(OH)D and peak power output in young adults is required.

  20. Vitamin D and the Epithelial to Mesenchymal Transition

    PubMed Central

    Larriba, María Jesús; García de Herreros, Antonio; Muñoz, Alberto

    2016-01-01

    Several studies support reciprocal regulation between the active vitamin D derivative 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) and the epithelial to mesenchymal transition (EMT). Thus, 1,25(OH)2D3 inhibits EMT via the induction of a variety of target genes that encode cell adhesion and polarity proteins responsible for the epithelial phenotype and through the repression of key EMT inducers. Both direct and indirect regulatory mechanisms mediate these effects. Conversely, certain master EMT inducers inhibit 1,25(OH)2D3 action by repressing the transcription of VDR gene encoding the high affinity vitamin D receptor that mediates 1,25(OH)2D3 effects. Consequently, the balance between the strength of 1,25(OH)2D3 signaling and the induction of EMT defines the cellular phenotype in each context. Here we review the current understanding of the genes and mechanisms involved in the interplay between 1,25(OH)2D3 and EMT. PMID:26880977

  1. Vitamin A intake, serum vitamin D and bone mineral density: analysis of the Korea National Health and Nutrition Examination Survey (KNHANES, 2008-2011).

    PubMed

    Joo, Nam-Seok; Yang, Sung-Won; Song, Byeng Chun; Yeum, Kyung-Jin

    2015-03-10

    The association of high vitamin A intake and low bone mineral density (BMD) is still controversial. To determine the association of dietary vitamin A intake and serum 25-hydroxyvitamin D (25(OH)D) concentration with BMD, a total of 6481 subjects (2907 men and 3574 women) aged ≥50 years from the Korean National Health and Nutrition Examination Survey (2008-2011) were divided into groups according to dietary vitamin A intake (tertiles) and serum 25(OH)D (<50, 50-75, >75 nmol/L), and evaluated for BMD after adjusting for relevant variables. Mean dietary vitamin A intakes were 737 and 600 μg RE (Retinol Equivalents) in men and women, respectively. Total hip and femoral neck BMD in men and lumbar spine BMD in women were both positively correlated with dietary vitamin A intake in subjects with serum 25(OH)D >75 nmol/L. Among men with serum 25(OH)D <50 nmol/L, both the top (mean 1353 μg RE) and bottom (mean 218 μg RE) tertiles of dietary vitamin A intake had lower BMD than the middle group (mean 577 μg RE). In this population, BMD was the highest among men and women with serum 25(OH)D = 50-75 nmol/L and that there were no differences in BMD by vitamin A intake in these vitamin D adequate groups. This cross-sectional study indicates that vitamin A intake does not affect bone mineral density as long as the serum 25(OH)D concentration is maintained in the moderate level of 50-75 nmol/L.

  2. Vitamin D Status in South Asian Populations - Risks and Opportunities.

    PubMed

    Akhtar, Saeed

    2016-08-17

    Human body acquires a significant amount of vitamin D by cutaneous synthesis under the action of sunlight and less is supplied through nutritional sources. Diversified sociocultural and economic determinants have been identified that limit the dietary intake of vitamin D and enough distribution of sunlight to maintain optimal levels of 25-hydroxyvitamin D (25(OH)D). Consequently, the world has witnessed a high prevalence of hypovitaminosis D in resource-limited South Asian countries. The purpose of this review is to provide a South Asian perspective of vitamin D status, critically examining India, Pakistan, Bangladesh, and Sri Lanka, and to shed light on potential determinants (latitude and season, sunshine exposure habits, age, gender, and genetic factors) leading to hypovitaminosis D among a variety of population groups. Literature search was carried out using bibliographic databases "PubMed," "Google Scholar," and "ScienceDirect.com." Serum 25(OH)D level, 20-50 nmol/L, was mainly taken as vitamin D deficiency, and determinants of low serum 25(OH)D concentration of the population under study were also considered. The review concludes that vitamin D deficiency is highly prevalent among South Asian populations and global efforts are needed to overcome hypovitaminosis in the region. In addition, dietary diversification, supplementation and fortification of foods with vitamin D, adequate exposure to sunlight, and consumption of animal foods were suggested as viable approaches to maintain 25(OH)D levels for optimal health.

  3. 1,25 (OH)2D3 enhances PTH-induced Ca2+ transients in preosteoblasts by activating L-type Ca2+ channels

    NASA Technical Reports Server (NTRS)

    Li, W.; Duncan, R. L.; Karin, N. J.; Farach-Carson, M. C.

    1997-01-01

    We previously demonstrated electrophysiologically that 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] shifts the activation threshold of L-type Ca2+ channels in osteoblasts toward the resting potential and prolongs mean open time. Presently, we used single-cell Ca2+ imaging to study the combined effects of 1,25(OH)2D3 and parathyroid hormone (PTH) during generation of Ca2+ transients in fura 2-loaded MC3T3-E1 cells. Pretreatment with 1,25(OH)2D3 concentrations, which alone did not produce Ca2+ transients, consistently enhanced Ca2+ responses to PTH. Enhancement was dose dependent over the range of 1 to 10 nM and was blocked by pretreatment with 5 microM nitrendipine during pretreatment. A 1,25(OH)2D3 analog that activates L-type channels and shifts their activation threshold also enhanced PTH responses. In contrast, an analog devoid of membrane Ca2+ effects did not enhance PTH-induced Ca2+ transients. The PTH-induced Ca2+ transient involved activation of a dihydropyridine-insensitive cation channel that was inhibited by Gd3+. Together, these data suggest that 1,25(OH)2D3 increases osteoblast responsiveness to PTH through rapid modification of L-type Ca2+ channel gating properties, whose activation enhances Ca2+ entry through other channels such as the PTH-responsive, Gd(3+)-sensitive cation channel.

  4. The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children

    PubMed Central

    Cairncross, Carolyn; Grant, Cameron; Stonehouse, Welma; Conlon, Cath; McDonald, Barry; Houghton, Lisa; Eyles, Darryl; Camargo, Carlos A.; Coad, Jane; von Hurst, Pamela

    2016-01-01

    Recent research on vitamin D in young children has expanded from bone development to exploring immunomodulatory effects. Our aim was to investigate the relationship of vitamin D status and allergic diseases in preschool-aged children in New Zealand. Dried capillary blood spots were collected from 1329 children during late-winter to early-spring for 25(OH)D measurement by LC-MS/MS. Caregivers completed a questionnaire about their child’s recent medical history. Analysis was by multivariable logistic regression. Mean 25(OH)D concentration was 52(SD19) nmol/L, with 7% of children <25 nmol/L and 49% <50 nmol/L. Children with 25(OH)D concentrations ≥75 nmol/L (n = 29) had a two-fold increased risk for parent-report of doctor-diagnosed food allergy compared to children with 25(OH)D 50–74.9 nmol/L (OR = 2.21, 1.33–3.68, p = 0.002). No associations were present between 25(OH)D concentration and presence of parent-reported eczema, allergic rhinoconjunctivitis or atopic asthma. Vitamin D deficiency was not associated with several allergic diseases in these New Zealand preschool children. In contrast, high 25(OH)D concentrations were associated with a two-fold increased risk of parental-report food allergy. This increase supports further research into the association between vitamin D status and allergic disease in preschool children. PMID:27258306

  5. The Relationship between Vitamin D Status and Allergic Diseases in New Zealand Preschool Children.

    PubMed

    Cairncross, Carolyn; Grant, Cameron; Stonehouse, Welma; Conlon, Cath; McDonald, Barry; Houghton, Lisa; Eyles, Darryl; Camargo, Carlos A; Coad, Jane; von Hurst, Pamela

    2016-06-01

    Recent research on vitamin D in young children has expanded from bone development to exploring immunomodulatory effects. Our aim was to investigate the relationship of vitamin D status and allergic diseases in preschool-aged children in New Zealand. Dried capillary blood spots were collected from 1329 children during late-winter to early-spring for 25(OH)D measurement by LC-MS/MS. Caregivers completed a questionnaire about their child's recent medical history. Analysis was by multivariable logistic regression. Mean 25(OH)D concentration was 52(SD19) nmol/L, with 7% of children <25 nmol/L and 49% <50 nmol/L. Children with 25(OH)D concentrations ≥75 nmol/L (n = 29) had a two-fold increased risk for parent-report of doctor-diagnosed food allergy compared to children with 25(OH)D 50-74.9 nmol/L (OR = 2.21, 1.33-3.68, p = 0.002). No associations were present between 25(OH)D concentration and presence of parent-reported eczema, allergic rhinoconjunctivitis or atopic asthma. Vitamin D deficiency was not associated with several allergic diseases in these New Zealand preschool children. In contrast, high 25(OH)D concentrations were associated with a two-fold increased risk of parental-report food allergy. This increase supports further research into the association between vitamin D status and allergic disease in preschool children.

  6. Vitamin D status during Pregnancy and Aspects of Offspring Health

    PubMed Central

    Ponsonby, Anne-Louise; Lucas, Robyn M.; Lewis, Sharon; Halliday, Jane

    2010-01-01

    Low maternal vitamin D levels during pregnancy have been linked to various health outcomes in the offspring, ranging from periconceptional effects to diseases of adult onset. Maternal and infant cord 25(OH)D levels are highly correlated. Here, we review the available evidence for these adverse health effects. Most of the evidence has arisen from observational epidemiological studies, but randomized controlled trials are now underway. The evidence to date supports that women should be monitored and treated for vitamin D deficiency during pregnancy but optimal and upper limit serum 25(OH)D levels during pregnancy are not known. PMID:22254029

  7. The serum 24,25-dihydroxyvitamin D concentration, a marker of vitamin D catabolism, is reduced in chronic kidney disease

    PubMed Central

    Bosworth, Cortney; Levin, Gregory; Robinson-Cohen, Cassianne; Hoofnagle, Andrew N.; Ruzinski, John; Young, Bessie; Schwartz, Stephen; Himmelfarb, Jonathan; Kestenbaum, Bryan; de Boer, Ian H.

    2012-01-01

    Chronic kidney disease is characterized, in part, as a state of decreased production of 1,25-dihydroxyvitamin D (1,25(OH)2D); however, this paradigm overlooks the role of vitamin D catabolism. We developed a mass spectrometric assay to quantify serum concentration of 24,25-dihydroxyvitamin D (24,25(OH)2D), the first metabolic product of 25-hydroxyvitamin D (25(OH)D) by CYP24A1, and determined its clinical correlates and associated outcomes among 278 participants with chronic kidney disease in the Seattle Kidney Study. For eGFRs of 60 or more, 45–59, 30–44, 15–29, and under 15 ml/min/1.73m2, the mean serum 24,25(OH)2D concentrations significantly trended lower from 3.6, 3.2, 2.6, 2.6, to 1.7 ng/ml, respectively. Non-Hispanic Black race, diabetes, albuminuria, and lower serum bicarbonate were also independently and significantly associated with lower 24,25(OH)2D concentrations. The 24,25(OH)2D concentration was more strongly correlated with that of parathyroid hormone than was 25(OH)D or 1,25(OH)2D. A 24,25(OH)2D concentration below the median was associated with increased risk of mortality in unadjusted analysis, but this was attenuated with adjustment for potential confounding variables. Thus, chronic kidney disease is a state of stagnant vitamin D metabolism characterized by decreases in both 1,25(OH)2D production and vitamin D catabolism. PMID:22648296

  8. Simultaneous measurement of plasma vitamin D3 metabolites including 4β,25-dihydroxyvitamin D3 using liquid chromatography-tandem mass spectrometry

    PubMed Central

    Wang, Zhican; Senn, Tauri; Kalhorn, Tom; Zheng, Xi Emily; Zheng, Songmao; Davis, Connie L.; Hebert, Mary F.; Lin, Yvonne S.; Thummel, Kenneth E.

    2011-01-01

    Simultaneous and accurate measurement of circulating vitamin D metabolites is critical to studies of the metabolic regulation of vitamin D and its impact on health and disease. To that end, we developed a specific LC-MS/MS method that permits the quantification of major circulating vitamin D3 metabolites in human plasma. Plasma samples were subjected to a protein precipitation, liquid-liquid extraction and Diels-Alder derivatization procedure prior to LC-MS/MS analysis. Importantly, in all human plasma samples tested, we identified a significant dihydroxyvitamin D3 peak that could potentially interfere with the determination of 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3] concentrations. This interfering metabolite has been identified as 4β,25-dihydroxyvitamin D3 [4β,25(OH)2D3] and was found at concentrations comparable to 1α,25(OH)2D3. Quantification of 1α,25(OH)2D3 in plasma required complete chromatographic separation of 1α,25(OH)2D3 from 4β,25(OH)2D3. An assay incorporating this feature was used to simultaneously determine the plasma concentrations of 25OHD3, 24R,25(OH)2D3, 1α,25(OH)2D3, and 4β,25(OH)2D3 in healthy individuals. The LC-MS/MS method developed and described here, could result in considerable improvement in the quantification of 1α,25(OH)2D3, as well as monitoring the newly identified circulating metabolite, 4β,25(OH)2D3. PMID:21784054

  9. Vitamin D status of older adults of diverse ancestry living in the greater Toronto area

    PubMed Central

    2013-01-01

    Background Physiological and lifestyle factors put older adults at an increased risk of vitamin D insufficiency and resulting negative health outcomes. Here we explore the vitamin D status in a sample of community dwelling older adults of diverse ancestry living in the Greater Toronto area (GTA). Methods Two hundred and twenty-four (224) adults over 60 years of age were recruited from the Square One Older Adult Centre, in Mississauga, Ontario. Circulating 25-hydroxyvitamin D (25(OH)D) concentrations were measured from dried blood spot cards. Dietary and supplemental intakes of vitamin D were assessed via questionnaires. Skin pigmentation was assessed quantitatively by measuring melanin levels using a reflectometer. Results The mean 25(OH)D concentration in the total sample was 82.4 nmol/L. There were no statistically significant differences in serum 25(OH)D concentrations, supplemental or dietary vitamin D intakes between the three major ancestral groups (East Asians, Europeans and South Asians). Females had significantly higher 25(OH)D concentrations than males (84.5 nmol/L vs. 72.2 nmol/L, p = 0.012). The proportion of participants with 25(OH)D concentrations below 50 nmol/L and 75 nmol/L were 12.1%, and 38.8%, respectively. The mean daily supplemental intake of vitamin D was 917 IU/day. Vitamin D intake from supplements was the major factor determining 25(OH)D concentrations (p < 0.001). Conclusions Mean concentration of 25(OH)D in a sample of older adults of diverse ancestry living in the GTA exceeded 80 nmol/L, and there were no significant differences in 25(OH)D levels between ancestral groups. These results sharply contrast with our recent study focused on young adults of diverse ancestry living in the same geographic area, in which we found substantially lower 25(OH)D concentrations (mean 39.5 nmol/L), low supplemental vitamin D intake (114 IU/day), and significant differences in 25(OH)D levels between ancestral groups. High daily intake

  10. Role of vitamin D in female reproduction.

    PubMed

    Shahrokhi, Seyedeh Zahra; Ghaffari, Firouzeh; Kazerouni, Faranak

    2016-04-01

    Vitamin D is a fat-soluble vitamin that belongs to the family of steroid hormones. The biological actions of vitamin D are exerted through a soluble protein, the vitamin D receptor (VDR). VDR is a transcription factor located in the nuclei of target cells that mediates the genomic action of the active form of vitamin D (1,25(OH)2D3). This transcription factor is distributed in various tissues, including the reproductive system. The presence of VDR in female reproductive tissue suggests that vitamin D is involved in female reproduction. The present article reviews the impact of vitamin D on anti-Müllerian hormone (AMH), as an ovarian reserve marker, and ovarian steroidogenesis. This article also discusses the impact of vitamin D as a factor that influences infertility and the outcome of in vitro fertilization (IVF), insulin resistance (IR), hyperandrogenism, endometriosis and polycystic ovary syndrome (PCOS).

  11. Vitamin D and cardiovascular disease: is the evidence solid?

    PubMed

    Al Mheid, Ibhar; Patel, Riyaz S; Tangpricha, Vin; Quyyumi, Arshed A

    2013-12-01

    Vitamin D deficiency, prevalent in 30-50% of adults in developed countries, is largely due to inadequate cutaneous production that results from decreased exposure to sunlight, and to a lesser degree from low dietary intake of vitamin D. Serum levels of 25-hydroxyvitamin D (25-OH D) <20 ng/mL indicate vitamin D deficiency and levels >30 ng/mL are considered optimal. While the endocrine functions of vitamin D related to bone metabolism and mineral ion homoeostasis have been extensively studied, robust epidemiological evidence also suggests a close association between vitamin D deficiency and cardiovascular morbidity and mortality. Experimental studies have demonstrated novel actions of vitamin D metabolites on cardiomyocytes, and endothelial and vascular smooth muscle cells. Low 25-OH D levels are associated with left ventricular hypertrophy, vascular dysfunction, and renin-angiotensin system activation. Despite a large body of experimental, cross-sectional, and prospective evidence implicating vitamin D deficiency in the pathogenesis of cardiovascular disease, a causal relationship remains to be established. Moreover, the cardiovascular benefits of normalizing 25-OH D levels in those without renal disease or hyperparathyroidism have not been established, and questions of an epiphenomenon where vitamin D status merely reflects a classic risk burden have been raised. Randomized trials of vitamin D replacement employing cardiovascular endpoints will provide much needed evidence for determining its role in cardiovascular protection.

  12. Vitamin D status and nutrition in Europe and Asia.

    PubMed

    Lips, P

    2007-03-01

    Vitamin D status is highly different in various countries of Europe, the Middle East and Asia. For this review, vitamin D deficiency is defined as serum 25-hydroxyvitamin D (25(OH)D) <25 nmol/l. Within European countries, serum 25(OH)D is <25 nmol/l in 2-30% of adults, increasing in the elderly and institutionalized to more than 80% in some studies. A north-south gradient was observed for serum 25(OH)D in the Euronut and MORE studies with higher levels in Scandinavia and lower levels in Italy and Spain and some Eastern European countries. This points to other determinants than sunshine, e.g. nutrition, food fortification and supplement use. Mean vitamin D intake in Scandinavia is 200-400IU/d, twice that in other European countries. Very low serum 25(OH)D levels have been reported in the Middle East, e.g. Turkey, Lebanon, Jordan and Iran. In these countries serum 25(OH)D was lower in women than in men and associated with clothing habits. In a Lebanese survey, vitamin D deficiency was observed in the majority and occurred mainly in veiled women. In India, vitamin D deficiency was observed in more than 30%, vitamin D status being poor in school children, pregnant women and large cities. Vitamin D status was much better in Malaysia and Singapore, but lower serum 25(OH)D was observed in Japan and China. Rickets and osteomalacia appear quite common in India, but precise data are lacking. Immigrants in Europe from the Middle East and Asia carry a high risk for vitamin D deficiency, pregnant women being especially at risk. Comparison of vitamin D status between countries is hampered by interlaboratory variation of serum 25(OH)D measurement. In addition, there is a need of population-based data. In conclusion, vitamin D deficiency is common in Southern Europe, the Middle East, India, China and Japan. It is less common in Northern Europe and Southeast Asia. Risk groups are young children, the elderly, pregnant women and non-western immigrants in Europe. Important

  13. The study of serum vitamin d and insulin resistance in chinese populations with normal glucose tolerance.

    PubMed

    Ding, Lin; Wang, Congcong; Ma, Heliang; Tian, Yuling; Lu, Yong; Pang, Shuguang

    2014-01-01

    Objectives. The aim of this study was to investigate the relationship between serum vitamin D and insulin resistance in Chinese subjects without diabetes mellitus. Methods. Serum 25(OH)D was measured in 897 individuals with normal glucose tolerance (NGT). Oral glucose tolerance tests (OGTTs) were conducted to exclude cases with diabetes, impaired fasting glucose (IFG), and impaired glucose tolerance (IGT). Metabolic parameters were measured and compared between the highest and lowest 25(OH)D quartiles. The relationship between serum 25(OH)D and homeostatic model assessment-insulin resistance (HOMA-IR) was analyzed. Results. Indexes, such as HOMA-IR, FINS, and SBP, were negatively correlated with serum 25(OH)D concentrations. Compared with the lowest quartile, individuals in the highest group had decreased Lg (HOMA-IR), Lg (FINS), and SBP. Pearson correlation analyses showed that serum 25(OH)D was negatively associated with age, BMI, Lg (HOMA-IR), and Lg (FINS). Multivariate linear regression analysis confirmed the negative correlation of Lg (HOMA-IR) and 25(OH)D. Conclusions. This study showed that serum 25(OH)D could be regarded as an independent predictor of insulin resistance for subjects without diabetes mellitus in China. Adequate vitamin D supplementation may improve multiple metabolic disturbances.

  14. Vitamin D: epidemiology of cardiovascular risks and events.

    PubMed

    Leu, Monica; Giovannucci, Edward

    2011-08-01

    Vitamin D may influence blood pressure through the renin-angiotensin system, parathyroid hormone levels, myocardial function, inflammation, and vascular calcification. In the past several years, a number of high-quality prospective studies have examined 25(OH)vitamin D (25(OH)D) levels in relation to risk of cardiovascular disease (CVD). Studies consistently show that levels of 25(OH)D below 20-25 ng/mL are associated with an increased risk of CVD incidence or mortality. Risk appears especially elevated at 25(OH)D levels below 10 or 15 ng/mL. It is unclear if levels higher that 25 ng/mL provide further benefits for CVD disease. Currently, results from randomized clinical trials are sparse and do not allow a definitive conclusion. Given other potential benefits of vitamin D, and low potential for toxicity, deficient levels below 25-30 ng/mL should be avoided and treated when identified. Further observational and randomized clinical trial data are important to better characterize the optimal range for 25(OH)D.

  15. Vitamin D and UV exposure in chronic kidney disease

    PubMed Central

    Krause, Rolfdieter

    2013-01-01

    With loss of renal function and decreasing glomerula filtration rate the serum levels of 25-hydroxyvitamin D [25(OH)D] as well as 1,25-dihydroxyvitamin D [1,25 (OH)2 D] often decrease simultaneously. In representative groups of German patients on renal replacement therapy (hemodialysis, peritoneal dialysis, kidney transplantation) our group retrospectively analyzed the vitamin D status over a period of 12 y (1995‒2006). Only 11% of patients had a serum level of 25(OH)D that was > 30 ng/ml, more than 70% had a level of 25(OH)D < 20 ng/ml. In clinical trials we used sun-simulating artificial lamps to produce vitamin D3 in the skin. Partial-body irradiation (15% of body surface) was used during the routine hemodialysis treatment. Whole-body UV exposure was done in a standing position three times a week before the hemodialysis treatment. With both procedures we observed an increase of the serum level of 25(OH)2D3 by approx. 35–50% over a period of 2‒3 mo, maintenance of trabecular bone mineral density and a normalization of systolic and diastolic blood pressure. Heart rate variability improved during the whole-body radiation intervention period by 20‒25%. Patients who continued the whole-body irradiation regularly two or three times before starting the routine hemodialysis session had maintained normal levels of circulating 25(OH)D3 and of 1,25(OH)2D3. Therefore, from our data it can be recommended that intermittent suberythemal UVB exposure with a sun-simulation spectrum is effective to treat and/or protect against vitamin D deficiency in chronic and end-stage kidney disease patients. PMID:24494043

  16. Vitamin D and UV exposure in chronic kidney disease.

    PubMed

    Krause, Rolfdieter

    2013-01-01

    With loss of renal function and decreasing glomerula filtration rate the serum levels of 25-hydroxyvitamin D [25(OH)D] as well as 1,25-dihydroxyvitamin D [1,25 (OH)2 D] often decrease simultaneously. In representative groups of German patients on renal replacement therapy (hemodialysis, peritoneal dialysis, kidney transplantation) our group retrospectively analyzed the vitamin D status over a period of 12 y (1995‒2006). Only 11% of patients had a serum level of 25(OH)D that was > 30 ng/ml, more than 70% had a level of 25(OH)D < 20 ng/ml. In clinical trials we used sun-simulating artificial lamps to produce vitamin D3 in the skin. Partial-body irradiation (15% of body surface) was used during the routine hemodialysis treatment. Whole-body UV exposure was done in a standing position three times a week before the hemodialysis treatment. With both procedures we observed an increase of the serum level of 25(OH)2D3 by approx. 35-50% over a period of 2‒3 mo, maintenance of trabecular bone mineral density and a normalization of systolic and diastolic blood pressure. Heart rate variability improved during the whole-body radiation intervention period by 20‒25%. Patients who continued the whole-body irradiation regularly two or three times before starting the routine hemodialysis session had maintained normal levels of circulating 25(OH)D3 and of 1,25(OH)2D3. Therefore, from our data it can be recommended that intermittent suberythemal UVB exposure with a sun-simulation spectrum is effective to treat and/or protect against vitamin D deficiency in chronic and end-stage kidney disease patients.

  17. Vitamin D effects on bone and muscle.

    PubMed

    Bischoff-Ferrari, Heike; Stähelin, Hannes B; Walter, Paul

    2011-07-01

    Increasing data suggest that higher 25-hydroxyvitamin D [25(OH)D] serum concentrations are advantageous for health. At present, strong evidence for causality is available for fracture and fall prevention, while promising epidemiologic and mechanistic studies suggest a key role of vitamin D in the preservation of cardiovascular health, and the prevention of cancer and other common chronic disease. For lower extremity function, fall prevention, hip bone density, and for fracture prevention optimal benefits are observed with 25(OH)D levels of at least 75 nmol/L to 100 nmol/L [1]. This threshold may be reached in 50 % of adults with 800 to 1000 IU vitamin D per day. This manuscript will discuss the evidence of vitamin D in fall and fracture prevention and how these data transfer to the most recent recommendations by the IOF (International Osteoporosis Foundation) and the IOM (Institute of Medicine).

  18. Evidence for aqueous soluble vitamin D-like substances in the calcinogenic plant, Tristetum flavescens.

    PubMed

    Morris, K M; Levack, V M

    1982-04-12

    A crude aqueous extract of the leaves of T. flavescens when administered orally to vitamin D-deficient chicks produced significant increases in plasma phosphate but had little effect on plasma calcium. When chicks, fed a high strontium diet to inhibit endogenous 1,25 (OH)2 vitamin D3 production and intestinal calcium transport, were dosed with the extract or synthetic 1,25 (OH)2D345Ca absorption from the duodenum in vivo was stimulated, whereas vitamin D3 was ineffective. Partial purification of the crude extract on a Sephadex GH25 column yielded two factors, one of which mimicked 1,25 (OH)2D3 activity in chicks fed the high strontium diet while the other produced a significant increase in plasma phosphate. The presence of these substances, together with previously demonstrated organic solvent soluble vitamin D-type activity, may account for the calcinogenic nature of the plant.

  19. Interactions between Vitamin D Deficiency and Phosphorus Depletion in the Rat

    PubMed Central

    Brautbar, Nachman; Walling, Marlin W.; Coburn, Jack W.; Steppe, John O.

    1979-01-01

    To evaluate the role of vitamin D in the physiologic response to phosphorus depletion (P depleton) and the response to vitamin D administration in P depletion, we studied vitamin D-deficient (−D) rats, fed either a normal or low phosphorus diet and then injected intraperitoneally on alternate days with replacement vitamin D3, 1.25 μg qod (D3); 1.25-dihydroxy-vitamin D3[1,25(OH)2D3] in physiologic, 54 ng qod (LD), and pharmacologic doses, 400 ng qod (HD); or vehicle alone (−D). The following results were obtained: (a) With P depletion, urinary excretion of inorganic phosphorus (Pi) fell to almost undetectable levels in −D rats, and two physiologic features of P depletion a calcemic effect and hypercalciuria, ensued. (b) With administration of vitamin D3 or 1,25(OH)2D3 in either doses to P-depleted rats, the renal retention of Pi was unaltered despite a significant elevation of serum Pi. (c) The calcemic response to P depletion was accentuated by vitamin D sterols, and the hypercalciuria of P depletion was reduced by 1,25(OH)2D3, HD > LD > D3. (d) In −D animals receiving normal Pi (+P), D3, and 1,25(OH)2D3, both LD and HD produced a significant calcemic and phosphatemic effect. (e) Urinary Pi excretion in +P animals was reduced slightly by vitamin D3 whereas 1,25(OH)2D3, both LD and HD, lowered urinary Pi markedly despite an increased serum Pi. (f) The serial values of serum Ca and Pi and urinary Ca in PD rats and the sequential values for urinary and serum Pi in +P rats indicated more rapid effects of 1,25(OH)2D3, both HD and LD, compared with D3. We conclude that: (a) The renal adaptation and physiologic response to PD does not require the presence of vitamin D. (b) 1,25(OH)2D3 may directly enhance the renal tubular reabsorption of Pi even as serum Pi rises. (c) A hypocalciuric action of 1,25(OH)2D3 in rats on low phosphorus diet could be direct or occur as a consequence of an increase in serum Pi produced by 1,25(OH)2D3. The different sequential renal

  20. Vitamin D regulates steroidogenesis and insulin-like growth factor binding protein-1 (IGFBP-1) production in human ovarian cells.

    PubMed

    Parikh, G; Varadinova, M; Suwandhi, P; Araki, T; Rosenwaks, Z; Poretsky, L; Seto-Young, D

    2010-09-01

    Vitamin D Receptor (VDR) is expressed in both animal and human ovarian tissue, however, the role of vitamin D in human ovarian steroidogenesis is unknown. Cultured human ovarian cells were incubated in tissue culture medium supplemented with appropriate substrates, with or without 50 pM-150 pM or 50 nM-150 nM of 1,25-(OH)2D3, and in the presence or absence of insulin. Progesterone, testosterone, estrone, estradiol, and IGFBP-1 concentrations in conditioned tissue culture medium were measured. Vitamin D receptor was present in human ovarian cells. 1,25-(OH)2D3 stimulated progesterone production by 13% (p<0.001), estradiol production by 9% (p<0.02), and estrone production by 21% (p<0.002). Insulin and 1,25-(OH)2D3 acted synergistically to increase estradiol production by 60% (p<0.005). 1,25-(OH)2D3 alone stimulated IGFBP-1 production by 24% (p<0.001), however, in the presence of insulin, 1,25-(OH)2D3 enhanced insulin-induced inhibition of IGFBP-1 production by 13% (p<0.009). Vitamin D stimulates ovarian steroidogenesis and IGFBP-1 production in human ovarian cells likely acting via vitamin D receptor. Insulin and vitamin D synergistically stimulate estradiol production. Vitamin D also enhances inhibitory effect of insulin on IGFBP-1 production.

  1. Seasonal Variability in Vitamin D Levels No Longer Detectable in Primary Hyperparathyroidism

    PubMed Central

    Cong, Elaine; Kepley, Anna; Zhang, Chiyuan; McMahon, Donald J.; Silverberg, Shonni J.

    2015-01-01

    Context: Seasonal variability in 25-hydroxyvitamin D [25(OH)D] and PTH levels in the general population has been associated with differences in bone turnover markers, bone density, and fracture risk. Seasonal variability in 25(OH)D and PTH levels has also been reported in primary hyperparathyroidism (PHPT). Objective: Given the widespread use of vitamin D supplements, we sought to determine whether patients with PHPT still demonstrated seasonal variation in 25(OH)D levels. Design and Setting: This cross-sectional study was conducted at a university medical center at a Northeastern U.S. latitude (New York, NY). Patients: One hundred patients with PHPT participated in the study. Outcome Measures: We assessed vitamin D supplement use and seasonal variation in serum 25(OH)D. Results: Patients had PHPT ([mean ± SD] calcium, 10.8 ± 1.0 mg/dL; PTH, 85 ± 48 pg/mL) with a mean 25(OH)D level of 29 ± 10 ng/mL. Although only one fifth of participants had vitamin D deficiency (19% < 20 ng/mL), more than half were either deficient or insufficient (54% < 30 ng/mL). Sun exposure varied by season, but there were no seasonal differences in levels of 25(OH)D, PTH, bone markers, or bone mineral density, or in the prevalence of 25(OH)D less than 20 or less than 30 ng/mL. Most of the participants (65%) took supplemental vitamin D (dose among users: mean, 1643 ± 1496 IU; median, 1000 IU daily), and supplement users had markedly better vitamin D status than nonusers (25(OH)D < 20 ng/mL: 8 vs 40%; P < .0001; < 30 ng/mL: 40 vs 80%; P = .0001; ≥ 30 ng/mL: 60 vs 20%; P = .0001). Conclusions: We found no evidence of seasonal variation in 25(OH)D levels or PHPT disease severity in the Northeastern United States. This change is likely due to widespread high vitamin D supplement intake, which has resulted in better vitamin D status among supplement users and can mask the effect of season on serum 25(OH)D levels. PMID:26120793

  2. Is there more to learn about functional vitamin D metabolism?

    PubMed

    DeLuca, Hector F

    2015-04-01

    The state of information on the enzymes responsible for the conversion of vitamin D3 to 1α,25-dhydroxyvitamin D3 (1,25-(OH)2D3), the metabolic active form responsible for the well-known function of vitamin D on calcium metabolism and bone mineralization has been briefly reviewed. There remains an unidentified enzyme responsible for 25% of the 25-hydroxylation of vitamin D3, while 75% of serum 25-hydroxyvitamin D3 (25-OH-D3) arises from CYP2R1. The well-established suppression of multiple sclerosis (MS) by sunlight has been confirmed using the mouse model, experimental autoimmune encephalomyelitis (EAE). This suppression results from a narrow band of ultraviolet light (300-315nm) that does not increase serum 25-OH-D3. Thus, UV light suppresses EAE by a mechanism not involving vitamin D. Vitamin D deficiency unexpectedly suppresses the development of EAE. Further, vitamin D receptor knockout in susceptible mice also prevents the development of EAE. On the other hand, deletion of CYP2R1 and the 1α-hydroxylase, CYP27B1, does not impair the development of EAE. Thus, either vitamin D itself or a heretofore-unknown metabolite is needed for the development of a component of the immune system necessary for development of EAE. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

  3. Assessment criteria for vitamin D deficiency/insufficiency in Japan: proposal by an expert panel supported by the Research Program of Intractable Diseases, Ministry of Health, Labour and Welfare, Japan, the Japanese Society for Bone and Mineral Research and the Japan Endocrine Society [Opinion].

    PubMed

    Okazaki, Ryo; Ozono, Keiichi; Fukumoto, Seiji; Inoue, Daisuke; Yamauchi, Mika; Minagawa, Masanori; Michigami, Toshimi; Takeuchi, Yasuhiro; Matsumoto, Toshio; Sugimoto, Toshitsugu

    2017-01-01

    Vitamin D is indispensable for the maintenance of bone and mineral health. Inadequate vitamin D action increases the risk for various musculoskeletal/mineral events including fracture, fall, secondary hyperparathyroidism, diminished response to antiresorptives, rickets/osteomalacia, and hypocalcemia. Its most common cause in recent years is vitamin D deficiency/insufficiency, clinically defined by a low serum 25-hydroxyvitamin D [25(OH)D] level. Guidelines for vitamin D insufficiency/deficiency defined by serum 25(OH)D concentrations have been published all over the world. In Japan, however, the information on the associations between serum 25(OH)D and bone and mineral disorders has not been widely shared among healthcare providers, partly because its measurement had not been reimbursed with national medical insurance policy until August 2016. We have set out to collect and analyze Japanese data on the relationship between serum 25(OH)D concentration and bone and mineral events. Integrating these domestic data and published guidelines worldwide, here, we present the following assessment criteria for vitamin D sufficiency/insufficiency/deficiency using serum 25(OH)D level in Japan. (1) Serum 25(OH)D level equal to or above 30 ng/ml is considered to be vitamin D sufficient. (2) Serum 25(OH)D level less than 30 ng/ml but not less than 20 ng/ml is considered to be vitamin D insufficient. (3) Serum 25(OH)D level less than 20 ng/ml is considered to be vitamin D deficient. We believe that these criteria will be clinically helpful in the assessment of serum 25(OH)D concentrations and further expect that they will form a basis for the future development of guidelines for the management of vitamin D deficiency/insufficiency.

  4. Assessment criteria for vitamin D deficiency/insufficiency in Japan - proposal by an expert panel supported by Research Program of Intractable Diseases, Ministry of Health, Labour and Welfare, Japan, The Japanese Society for Bone and Mineral Research and The Japan Endocrine Society [Opinion].

    PubMed

    Okazaki, Ryo; Ozono, Keiichi; Fukumoto, Seiji; Inoue, Daisuke; Yamauchi, Mika; Minagawa, Masanori; Michigami, Toshimi; Takeuchi, Yasuhiro; Matsumoto, Toshio; Sugimoto, Toshitsugu

    2017-01-30

    Vitamin D is indispensable for the maintenance of bone and mineral health. Inadequate vitamin D action increases the risk for various musculoskeletal/mineral events including fracture, fall, secondary hyperparathyroidism, diminished response to antiresorptives, rickets/osteomalacia, and hypocalcemia. Its most common cause in recent years is vitamin D deficiency/insufficiency, clinically defined by low serum 25-hydroxyvitamin D [25(OH)D] level. Guidelines for vitamin D insufficiency/deficiency defined by serum 25(OH)D concentrations have been published all over the world. In Japan, however, the information on the associations between serum 25(OH)D and bone and mineral disorders has not been widely shared among healthcare providers, partly because its measurement had not been reimbursed with national medical insurance policy until August 2016. We have set out to collect and analyze Japanese data on the relationship between serum 25(OH)D concentration and bone and mineral events. Integrating these domestic data and published guidelines worldwide, here we present the following assessment criteria for vitamin D sufficiency/insufficiency/deficiency using serum 25(OH)D level in Japan. 1) Serum 25(OH)D level equal to or above 30 ng/mL is considered to be vitamin D sufficient. 2) Serum 25(OH)D level less than 30 ng/mL but not less than 20 ng/mL is considered to be vitamin D insufficient. 3) Serum 25(OH)D level less than 20 ng/mL is considered to be vitamin D deficient. We believe that these criteria will be clinically helpful in the assessment of serum 25(OH)D concentrations and further expect that they will form a basis for the future development of guidelines for the management of vitamin D deficiency/insufficiency.

  5. Vitamin D deficiency is prevalent in girls and women with rett syndrome

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of the study was to determine the prevalence of vitamin D deficiency and identify the relation between 25-hydroxyvitamin D (25-(OH)D) levels and the consumption of dietary sources of vitamin D or exposure to anticonvulsants in girls and women with Rett syndrome (RTT). Retrospective review of...

  6. Vitamin D Status and Anthropometric Indices of an Omani Study Population

    PubMed Central

    Abiaka, Clifford; Delghandi, Marit; Kaur, Meenu; Al-Saleh, Mohsin

    2013-01-01

    Objectives: Serum 25-hydroxyvitamin D [25(OH)D] concentrations reflect vitamin D status, with deficiency implicated as causative of many diseases. This study assessed vitamin D status and anthropometric indices in a sample of healthy Omanis. Methods: Serum 25(OH)D concentrations were measured by high performance liquid chromatography in 206 healthy Omanis, aged 18–55 years (mean age: men 31.1, women 26.8) in Muscat, Oman. Of this number, 95% indicated that they had never taken vitamin D supplements. Findings were compared with published values for populations domiciled in more northerly latitudes. Classical procedures were used to determine global obesity (body mass index [BMI]), and central obesity determined by waist circumference, waist-to-hip ratio (WHR), and waist-to-height ratio. Results: Women, as compared to men, had markedly lower concentrations of 25(OH)D. Applying the cut-off point of serum 25(OH)D levels at 50 nmol/L, the prevalence of vitamin D deficiency in the study population was 87.5%; this was higher than the rates reported for the British, and European-, Hispanic-, and African-Americans. At a BMI cut-point of ≥30 kg/m2, the prevalence of obesity was 14.6%; this was lower than the rates reported for European-, Hispanic-, and African-Americans. Levels of 25(OH) D increased relative to age and obesity. WHR was the main predictor of 25(OH)D levels. Conclusion: The striking vitamin D deficiency seen in the study population, relative to more northerly populations, may be linked to sun avoidance, inadequate dietary vitamin D, and virtual non-intake of supplemental vitamin D. Age and male-gender determined the status of vitamin D and of obesity. PMID:23862027

  7. Effect of lowered vitamin D binding protein levels on the biological activity and metabolism of 1,25-dihydroxyvitamin D/sub 3/

    SciTech Connect

    Kost, S.B.; Londowski, J.; Audran, M.; Kumar, R.

    1986-03-01

    The authors studied the effect of lowered vitamin D binding protein levels on the biological activity and metabolism of 1,25-dihydroxyvitamin D/sub 3/ (1,25(OH)/sub 2/D/sub 3/) in vivo. Estrogen administration to vitamin D-deficient rats resulted in decrease of plasma vitamin D binding protein concentrations by about 20%. The authors administered graded doses of 1,25(OH)/sub 2/D/sub 3/ (5 - 5000 pmol intravenously) to vitamin D-deficient rats given estrogen or vehicle, and studied the biological response in intestine and bone. Intestinal calcium transport, following the administration of 1,25(OH)/sub 2/D/sub 3/, was similar in the estrogen or vehicle-treated groups. Serum calcium concentrations were lower in the estrogen-treated rats when compared to rats given vehicle. Serum calcium in both groups, however, increased the same amount over the range of 1,25(OH)/sub 2/D/sub 3/ given. The uptake of (/sup 3/H) 1,25(OH)/sub 2/D/sub 3/ by the intestine and bone 8 hours after the administration of (/sup 3/H) 1,25(OH)/sub 2/D/sub 3/ was similar in estrogen- and vehicle-treated rats. The amount of (/sup 3/H) 1,25(OH)/sub 2/D/sub 3/ in plasma of estrogen-treated rats was the same as in vehicle-treated rats. The authors conclude that in estrogen-treated rats, lowered vitamin D binding protein levels do not alter the effect of 1,25(OH)/sub 2/D/sub 3/ on intestine or bone and do not alter the metabolism of 1,25(OH)/sub 2/D/sub 3/.

  8. Vitamin D status and recommendations to improve vitamin D status in Canadian youth.

    PubMed

    Mark, Sean

    2010-10-01

    Little is known regarding the vitamin D status of Canadian youth. Our objectives were (i) to describe the vitamin D status of Quebec youth using a representative sample; (ii) to examine the relative contributions of diet, physical activity, and fat mass to the variance in plasma 25-hydroxyvitamin D(25(OH)D), the best biomarker of vitamin D status; and (iii) to examine the influence of household income and food insecurity on the intakes of dietary vitamin D, calcium, and dairy foods. To describe vitamin D status, we used data from the Quebec Child and Adolescent Health and Social Survey (QCAHS), which is a cross-sectional survey representative of Quebec youth aged 9, 13, and 16 years. For the second objective, 159 youth, aged 8 to 11 years, whose parents (at least one) were obese or had the metabolic syndrome, were used for cross-sectional analysis in the Quebec Adipose and Lifestyle InvesTigation in Youth (QUALITY). Fat mass was measured using dual X-ray absorptiometry (DXA), and physical activity was assessed by an accelerometer. Finally, we analyzed data from the Canadian Community Health Survey (CCHS), which collected data from 9 to 18 year olds (N = 8960), and was representative of Canadian youth. From this survey a single 24-h dietary recall, measured height and weight, sociodemographic, and food insecurity information were available. In both the QUALITY and QCAHS study, >90% of youth had suboptimal vitamin D levels (plasma 25(OH)D < 75 nmol L(-1)) at the end of winter and beginning of spring. In the QCAHS study, older youth had a higher prevalence of vitamin D deficiency (25(OH)D < 27.5 nmol L(-1)) (>10%) than younger youth, and girls from low-income households had lower plasma 25(OH)D concentrations. In the QUALITY study, milk consumption and physical activity had modest associations with plasma 25(OH)D, corresponding to 2.9 nmol L(-1) and 2.1 nmol L(-1) higher plasma 25(OH)D per standard deviation increase in these exposures, respectively. In the CCHS study

  9. Serum 25-Hydroxy Vitamin D and Survival in Advanced Colorectal Cancer: A Retrospective Analysis

    PubMed Central

    Wesa, Kathleen M.; Segal, Neil H.; Cronin, Angel M.; Sjoberg, Daniel D.; Jacobs, Gria N.; Coleton, Marci I.; Fleisher, Martin; Dnistrian, Ann M.; Saltz, Leonard B.; Cassileth, Barrie R.

    2015-01-01

    Background Higher serum 25-hydroxy vitamin D [25(OH)D] levels are associated with decreased colorectal cancer (CRC) incidence. In this retrospective study of stage IV CRC patients, we evaluate whether 25(OH)D levels at diagnosis correlate with survival. Methods Stored sera from carcinoembryonic antigen (CEA) measurements obtained between February 2005 and March 2006 were screened. The first 250 patients with CEA ±30 days of stage IV CRC diagnosis were included. Serum 25(OH)D levels were determined and categorized as adequate ≥30 ng/mL, or deficient <30 ng/mL. Multivariable Cox regression models controlling for albumin and Eastern Cooperative Oncology Group performance status were used to investigate whether higher 25(OH)D levels were associated with prolonged survival. Results A total of 207 patients (83%) were vitamin D-deficient (median, 21 ng/mL), with deficiencies significantly more likely among non-Hispanic black patients (P=0.009). Higher levels were associated with prolonged survival in categorical variable analysis: adequate vs deficient, hazard ratio 0.61, 95% CI 0.38–0.98, P=0.041. Conclusions A majority of newly diagnosed stage IV CRC patients are vitamin D-deficient. Our data suggest that higher 25(OH)D levels are associated with better overall survival. Clinical trials to determine whether aggressive vitamin D repletion would improve outcomes for vitamin D-deficient CRC patients are warranted. PMID:25646565

  10. Analysis of vitamin D status at two academic medical centers and a national reference laboratory: result patterns vary by age, gender, season, and patient location

    PubMed Central

    2013-01-01

    Background Testing for 25-hydroxyvitamin D [25(OH)D] has increased dramatically in recent years. The present report compares overall utilization and results for 25(OH)D orders at two academic medical centers - one in New York and one in Iowa – in order to characterize the vitamin D status of our inpatient and outpatient populations. Results are also compared to those from a national reference laboratory to determine whether patterns at these two institutions reflect those observed nationally. Methods Retrospective data queries of 25(OH)D orders and results were conducted using the laboratory information systems at Weill Cornell Medical College / New York Presbyterian Hospital (WCMC), University of Iowa Hospitals and Clinics (UIHC), and ARUP Laboratories (ARUP). Chart review was conducted for cases with very high or low serum 25(OH)D levels in the WCMC and UIHC datasets. Results The majority of tests were ordered on females and outpatients. Average serum 25(OH)D levels were higher in female versus male patients across most ages in the WCMC, UIHC, and ARUP datasets. As expected, average serum 25(OH)D levels were higher in outpatients than inpatients. Serum 25(OH)D levels showed seasonal periodicity, with average levels higher in summer than winter and correlating to regional UV index. Area plots demonstrated a peak of increased 25(OH)D insufficiency / deficiency in adolescent females, although overall worse 25(OH)D status was found in male versus female patients in the WCMC, UIHC, and ARUP datasets. Surprisingly, improved 25(OH)D status was observed in patients starting near age 50. Finally, chart review of WCMC and UIHC datasets revealed over-supplementation (especially of ≥ 50,000 IU weekly doses) in the rare cases of very high 25(OH)D levels. General nutritional deficiency and/or severe illness was found in most cases of severe 25(OH)D deficiency. Conclusions 25(OH)D status of patients seen by healthcare providers varies according to age, gender, season

  11. Serum Vitamin D Is Significantly Inversely Associated with Disease Severity in Caucasian Adults with Obstructive Sleep Apnea Syndrome

    PubMed Central

    Kerley, Conor P.; Hutchinson, Katrina; Bolger, Kenneth; McGowan, Aisling; Faul, John; Cormican, Liam

    2016-01-01

    Study Objectives: To evaluate vitamin D (25(OH)D) levels in obstructive sleep apnea syndrome (OSAS) and possible relationships to OSAS severity, sleepiness, lung function, nocturnal heart rate (HR), and body composition. We also aimed to compare the 25(OH)D status of a subset of OSAS patients compared to controls matched for important determinants of both OSAS and vitamin D deficiency (VDD). Methods: This was a cross-sectional study conducted at an urban, clinical sleep medicine outpatient center. We recruited newly diagnosed, Caucasian adults who had recently undergone nocturnal polysomnography. We compared body mass index (BMI), body composition (bioelectrical impedance analysis), neck circumference, sleepiness (Epworth Sleepiness Scale), lung function, and vitamin D status (serum 25-hydrpoxyvitamin D (25(OH)D) across OSAS severity categories and non-OSAS subjects. Next, using a case-control design, we compared measures of serum 25(OH)D from OSAS cases to non-OSAS controls who were matched for age, gender, skin pigmentation, sleepiness, season, and BMI. Results: 106 adults (77 male; median age = 54.5; median BMI = 34.3 kg/m2) resident in Dublin, Ireland (latitude 53°N) were recruited and categorized as non-OSAS or mild/moderate/severe OSAS. 98% of OSAS cases had insufficient 25(OH)D (< 75 nmol/L), including 72% with VDD (< 50 nmol/L). 25(OH)D levels decreased with OSAS severity (P = 0.003). 25(OH)D was inversely correlated with BMI, percent body fat, AHI, and nocturnal HR. Subsequent multivariate regression analysis revealed that 25(OH)D was independently associated with both AHI (P = 0.016) and nocturnal HR (P = 0.0419). Our separate case-control study revealed that 25(OH)D was significantly lower in OSAS cases than matched, non-OSAS subjects (P = 0.001). Conclusions: We observed widespread vitamin D deficiency and insufficiency in a Caucasian, OSAS population. There were significant, independent, inverse relationships between 25(OH)D and AHI as well as

  12. Vitamin D Intake and Status in 6-Year-Old Icelandic Children Followed up from Infancy

    PubMed Central

    Thorisdottir, Birna; Gunnarsdottir, Ingibjorg; Steingrimsdottir, Laufey; Palsson, Gestur I.; Birgisdottir, Bryndis E.; Thorsdottir, Inga

    2016-01-01

    High serum 25-hydroxyvitamin D (25(OH)D) levels have been observed in infants in Nordic countries, likely due to vitamin D supplement use. Internationally, little is known about tracking vitamin D status from infancy to childhood. Following up 1-year-old infants in our national longitudinal cohort, our aims were to study vitamin D intake and status in healthy 6-year-old Icelandic children (n = 139) and to track vitamin D status from one year of age. At six years, the mean 25(OH)D level was 56.5 nmol/L (SD 17.9) and 64% of children were vitamin D sufficient (25(OH)D ≥ 50 nmol/L). A logistic regression model adjusted for gender and breastfeeding showed that higher total vitamin D intake (Odds ratio (OR) = 1.27, 95% confidence interval (CI) = 1.08–1.49), blood samples collected in summer (OR = 8.88, 95% CI = 1.83–43.23) or autumn (OR = 5.64, 95% CI = 1.16–27.32) compared to winter/spring, and 25(OH)D at age one (OR = 1.02, 95% CI = 1.002–1.04) were independently associated with vitamin D sufficiency at age six. The correlation between 25(OH)D at age one and six was 0.34 (p = 0.003). Our findings suggest that vitamin D status in infancy, current vitamin D intake and season are predictors of vitamin D status in early school age children. Our finding of vitamin D status tracking from infancy to childhood provides motivation for further studies on tracking and its clinical significance. PMID:26861385

  13. Vitamin D Intake and Status in 6-Year-Old Icelandic Children Followed up from Infancy.

    PubMed

    Thorisdottir, Birna; Gunnarsdottir, Ingibjorg; Steingrimsdottir, Laufey; Palsson, Gestur I; Birgisdottir, Bryndis E; Thorsdottir, Inga

    2016-02-04

    High serum 25-hydroxyvitamin D (25(OH)D) levels have been observed in infants in Nordic countries, likely due to vitamin D supplement use. Internationally, little is known about tracking vitamin D status from infancy to childhood. Following up 1-year-old infants in our national longitudinal cohort, our aims were to study vitamin D intake and status in healthy 6-year-old Icelandic children (n = 139) and to track vitamin D status from one year of age. At six years, the mean 25(OH)D level was 56.5 nmol/L (SD 17.9) and 64% of children were vitamin D sufficient (25(OH)D ≥ 50 nmol/L). A logistic regression model adjusted for gender and breastfeeding showed that higher total vitamin D intake (Odds ratio (OR) = 1.27, 95% confidence interval (CI) = 1.08-1.49), blood samples collected in summer (OR = 8.88, 95% CI = 1.83-43.23) or autumn (OR = 5.64, 95% CI = 1.16-27.32) compared to winter/spring, and 25(OH)D at age one (OR = 1.02, 95% CI = 1.002-1.04) were independently associated with vitamin D sufficiency at age six. The correlation between 25(OH)D at age one and six was 0.34 (p = 0.003). Our findings suggest that vitamin D status in infancy, current vitamin D intake and season are predictors of vitamin D status in early school age children. Our finding of vitamin D status tracking from infancy to childhood provides motivation for further studies on tracking and its clinical significance.

  14. Determinants of Vitamin D Status among Overweight and Obese Puerto Rican Adults

    PubMed Central

    Palacios, Cristina; Gil, Karen; Pérez, Cynthia M.; Joshipura, Kaumudi

    2012-01-01

    Background/Aims Low vitamin D status is highly prevalent worldwide, and the major determinants are sun exposure and vitamin D intake. We aimed to measure vitamin D status in a sample of overweight/obese adults in Puerto Rico, an area with plenty of sun exposure, and relate it to vitamin D intake, sun exposure and body composition. Methods Serum 25(OH)D levels (liquid chromatography-tandem mass spectrometry), body weight and fat (bioimpedance), vitamin D intake and sun exposure (questionnaires) were assessed. Analysis included age-adjusted correlations and multivariate regression. Results In 98 subjects (66% females; 40–65 years), median serum 25(OH)D levels were 30.7 ng/ml (25–75th percentile 25.0–37.3); 55% had levels >30 ng/ml, 31% had levels between 20 and 30 ng/ml and 14% had levels <20 ng/ml. Total vitamin D intake was 180 IU/day (45–615), and the sun exposure score was 22 (17–27). After adjusting for gender, 25(OH)D levels were significantly correlated with vitamin D intake (r = 0.24, p = 0.018), the sum of sun exposure and vitamin D intake indices (r = 0.34, p = 0.001) and percent body fat (r = −0.25, p = 0.01). After adjusting for age, gender and percent body fat, the sum of sun exposure and vitamin D intake indices remained statistically associated with 25(OH)D levels (β = 1.5, p < 0.01). Conclusions In this group of overweight and obese individuals, 25(OH)D was significantly related to vitamin D intake, sun exposure and vitamin D intake indices and percent body fat. PMID:22222318

  15. Prostatic compensation of the vitamin D axis in African American men

    PubMed Central

    Richards, Zachary; Batai, Ken; Farhat, Rachael; Shah, Ebony; Makowski, Andrew; Gann, Peter H.; Kittles, Rick

    2017-01-01

    BACKGROUND. African American (AA) men are disproportionately affected by both prostate cancer (PCa) and vitamin D deficiency compared with European American (EA) men. Vitamin D deficiency is linked to increased PCa aggressiveness and mortality. Therefore, it has been hypothesized that vitamin D deficiency may contribute to the PCa disparity between AA and EA men. METHODS. We studied a cross sectional group of 60 PCa patients (AA, n = 31; EA, n = 29) who underwent radical prostatectomy. Vitamin D metabolites 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D (1,25(OH)2D) were measured in the serum and tissue by uHPLC-MS-MS. Tissue was laser capture microdissected, and gene expression was quantified by microarray. DNA isolated from whole blood was genotyped for West African ancestry markers and vitamin D–related SNPs. RESULTS. Serum concentrations of 25(OH)D were lower in AAs, but concentrations of 1,25(OH)2D in the prostate tissue were higher compared with EAs. Expression of the vitamin D receptor was higher in prostate tissue from AAs. Expression of the extracellular receptor of vitamin D binding protein, LRP2, was positively associated with West African ancestry and inversely associated with tissue 25(OH)D concentrations in AAs. CONCLUSIONS. The relationships between vitamin D binding protein LRP2 and vitamin D metabolites suggest that the prohormone is actively transported into the prostate, followed by intraprostatic conversion to the active hormone, rather than passive diffusion. These findings support the presence of a compensatory response in prostate tissue to vitamin D deficiency in AAs and reveal a previously unknown complexity involving tissue distribution of vitamin D metabolites. FUNDING. Department of Defense Prostate Cancer Research Program Idea Award for Disparities Research PC121923 (LN and RK) and the NIH 1R01MD007105 (RK). PMID:28138564

  16. Dietary diallyl disulfide supplementation attenuates ethanol-mediated pulmonary vitamin D speciate depletion in C57Bl/6 mice

    PubMed Central

    McCaskill, Michael L.; Hottor, Henry T.; Sapkota, Muna; Wyatt, Todd A.

    2016-01-01

    Background Slightly more than 5 % of the United States population heavily consumes ethanol, i.e., more than 14 drinks for men and 7 drinks for women a week. Chronic ethanol consumption can result in increased liver disease, reduced recovery from burn injury, and more frequent and severe respiratory infections. Chronic ethanol over-consumption also leads to vitamin D dysmetabolism and depletion. Vitamin D is a fat-soluble pro-hormone that regulates musculoskeletal health, cellular proliferation/differentiation, and innate and adaptive immune response. Methods In this study, C57BL/6 mice were fed 20 % ethanol in their water ad libitum for 7 weeks. Some mice were fed either a standard chow or a modified diet containing 0.15 μg/day of diallyl disulfide (DADS). Whole blood, lung tissue, and bronchial alveolar lavage fluid (BALF) were collected at sacrifice and analyzed for 25(OH) D3, 1,25 (OH)2D3, vitamin D receptor VDR, CYP2E1, and CYP27B1 levels. Results Ethanol reduced 25(OH) D3 and 1,25 (OH)2D3 in lung tissue and BALF on average 31 %. The largest ethanol-mediated reduction was in the 1,25 (OH)2D3 (42 %) measured in the BALF. Dietary supplementation of DADS restored BALF and lung tissue protein of 25(OH) D3 and 1,25(OH)2D3 to control levels. Chronic ethanol consumption also resulted in tissue increases of vitamin D response (VDR) protein, Cyp2E1, and reductions in vitamin D-activating enzyme CYP27B1. All three of these effects were attenuated by dietary supplementation of DADS. Conclusions In conclusion, the pulmonary metabolic disturbances mediated by chronic ethanol consumption as measured by 1,25(OH)2D3 protein levels, epithelial lining fluid, and lung tissue can be ameliorated by dietary supplementation of DADS in C57BL/6 mice. PMID:27536382

  17. Vitamin D and Sunlight: Strategies for Cancer Prevention and Other Health Benefits

    PubMed Central

    Holick, Michael F.

    2008-01-01

    Vitamin D deficiency is a worldwide health problem. The major source of vitamin D for most humans is sensible sun exposure. Factors that influence cutaneous vitamin D production include sunscreen use, skin pigmentation, time of day, season of the year, latitude, and aging. Serum 25-hydroxyvitamin D [25(OH)D] is the measure for vitamin D status. A total of 100 IU of vitamin D raises blood level of 25(OH)D by 1 ng/ml. Thus, children and adults who do not receive adequate vitamin D from sun exposure need at least 1000 IU/d vitamin D. Lack of sun exposure and vitamin D deficiency have been linked to many serious chronic diseases, including autoimmune diseases, infectious diseases, cardiovascular disease, and deadly cancers. It is estimated that there is a 30 to 50% reduction in risk for developing colorectal, breast, and prostate cancer by either increasing vitamin D intake to least 1000 IU/d vitamin D or increasing sun exposure to raise blood levels of 25(OH)D >30 ng/ml. Most tissues in the body have a vitamin D receptor. The active form of vitamin D, 1,25-dihydroxyvitamin D, is made in many different tissues, including colon, prostate, and breast. It is believed that the local production of 1,25(OH)2D may be responsible for the anticancer benefit of vitamin D. Recent studies suggested that women who are vitamin D deficient have a 253% increased risk for developing colorectal cancer, and women who ingested 1500 mg/d calcium and 1100 IU/d vitamin D3 for 4 yr reduced risk for developing cancer by >60%. PMID:18550652

  18. Vitamin D and sunlight: strategies for cancer prevention and other health benefits.

    PubMed

    Holick, Michael F

    2008-09-01

    Vitamin D deficiency is a worldwide health problem. The major source of vitamin D for most humans is sensible sun exposure. Factors that influence cutaneous vitamin D production include sunscreen use, skin pigmentation, time of day, season of the year, latitude, and aging. Serum 25-hydroxyvitamin D [25(OH)D] is the measure for vitamin D status. A total of 100 IU of vitamin D raises blood level of 25(OH)D by 1 ng/ml. Thus, children and adults who do not receive adequate vitamin D from sun exposure need at least 1000 IU/d vitamin D. Lack of sun exposure and vitamin D deficiency have been linked to many serious chronic diseases, including autoimmune diseases, infectious diseases, cardiovascular disease, and deadly cancers. It is estimated that there is a 30 to 50% reduction in risk for developing colorectal, breast, and prostate cancer by either increasing vitamin D intake to least 1000 IU/d vitamin D or increasing sun exposure to raise blood levels of 25(OH)D >30 ng/ml. Most tissues in the body have a vitamin D receptor. The active form of vitamin D, 1,25-dihydroxyvitamin D, is made in many different tissues, including colon, prostate, and breast. It is believed that the local production of 1,25(OH)(2)D may be responsible for the anticancer benefit of vitamin D. Recent studies suggested that women who are vitamin D deficient have a 253% increased risk for developing colorectal cancer, and women who ingested 1500 mg/d calcium and 1100 IU/d vitamin D(3) for 4 yr reduced risk for developing cancer by >60%.

  19. Antiproliferative effects of 1alpha,25-dihydroxyvitamin D(3) and vitamin D analogs on tumor-derived endothelial cells.

    PubMed

    Bernardi, Ronald J; Johnson, Candace S; Modzelewski, Ruth A; Trump, Donald L

    2002-07-01

    Although there is abundant evidence that 1alpha,25-dihydroxyvitamin D(3) [1,25-(OH)(2)D(3)] inhibits the growth of several cancer cell types, inhibition of angiogenesis may also play a role in mediating the antitumor effects of 1,25-(OH)(2)D(3.) We examined the ability of 1,25-(OH)(2)D(3) to inhibit the growth of tumor-derived endothelial cells (TDECs) and normal endothelial cells and to modulate angiogenic signaling. 1,25-(OH)(2)D(3) inhibited the growth of TDECs from two tumor models at nanomolar concentrations, but was less potent against normal aortic or yolk sac endothelial cells. The vitamin D analogs Ro-25-6760, EB1089, and ILX23-7553 were also potent inhibitors of TDEC proliferation. Furthermore, the combination of 1,25-(OH)(2)D(3) and dexamethasone had greater activity than either agent alone. 1,25-(OH)(2)D(3) increased vitamin D receptor and p27(Kip1) protein levels in TDECs, whereas phospho-ERK1/2 and phospho-Akt levels were reduced. These changes were not observed in normal aortic endothelial cells. In squamous cell carcinoma and radiation-induced fibrosarcoma-1 cells, 1,25-(OH)(2)D(3) treatment caused a reduction in the angiogenic signaling molecule, angiopoietin-2. In conclusion, 1,25-(OH)(2)D(3) and its analogs directly inhibit TDEC proliferation at concentrations comparable to those required to inhibit tumor cells. Further, 1,25-(OH)(2)D(3) modulates cell cycle and survival signaling in TDECs and affects angiogenic signaling in cancer cells. Thus, our work supports the hypothesis that angiogenesis inhibition plays a role in the antitumor effects of 1,25-(OH)(2)D(3).

  20. Altered Calcium and Vitamin D Homeostasis in First-Time Calcium Kidney Stone-Formers

    PubMed Central

    Ketha, Hemamalini; Singh, Ravinder J.; Grebe, Stefan K.; Bergstralh, Eric J.; Rule, Andrew D.; Lieske, John C.; Kumar, Rajiv

    2015-01-01

    Background Elevated serum 1,25-dihydroxyvitamin D (1,25(OH)2D) concentrations have been reported among cohorts of recurrent calcium (Ca) kidney stone-formers and implicated in the pathogenesis of hypercalciuria. Variations in Ca and vitamin D metabolism, and excretion of urinary solutes among first-time male and female Ca stone-formers in the community, however, have not been defined. Methods In a 4-year community-based study we measured serum Ca, phosphorus (P), 25-hydroxyvitamin D (25(OH)D), 1,25(OH)2D, 24,25-dihydroxyvitamin D (24,25(OH)2D), parathyroid hormone (PTH), and fibroblast growth factor-23 (FGF-23) concentrations in first-time Ca stone-formers and age- and gender frequency-matched controls. Results Serum Ca and 1,25(OH)2D were increased in Ca stone-formers compared to controls (P = 0.01 and P = 0.001). Stone-formers had a lower serum 24,25(OH)2D/25(OH)D ratio compared to controls (P = 0.008). Serum PTH and FGF-23 concentrations were similar in the groups. Urine Ca excretion was similar in the two groups (P = 0.82). In controls, positive associations between serum 25(OH)D and 24,25(OH)2D, FGF-23 and fractional phosphate excretion, and negative associations between serum Ca and PTH, and FGF-23 and 1,25(OH)2D were observed. In SF associations between FGF-23 and fractional phosphate excretion, and FGF-23 and 1,25(OH)2D, were not observed. 1,25(OH)2D concentrations associated more weakly with FGF-23 in SF compared with C (P <0.05). Conclusions Quantitative differences in serum Ca and 1,25(OH)2D and reductions in 24-hydroxylation of vitamin D metabolites are present in first-time SF and might contribute to first-time stone risk. PMID:26332888

  1. 25-Hydroxy-Vitamin D Concentration Is Not Affected by Severe or Non-Severe Pneumonia, or Inflammation, in Young Children

    PubMed Central

    Haugen, Johanne; Chandyo, Ram K.; Ulak, Manjeswori; Mathisen, Maria; Basnet, Sudha; Brokstad, Karl A.; Valentiner-Branth, Palle; Shrestha, Prakash S.; Strand, Tor A.

    2017-01-01

    Poor vitamin D status has been associated with increased risk and severity of respiratory tract infections. Whether or not inflammation and infection affects 25-hydroxy vitamin D (25(OH)D) concentration is controversial and is important in the interpretation of observational studies using plasma-25(OH)D as a biomarker for status. Our objectives were to measure whether 25(OH)D concentration was altered by an episode of acute lower respiratory tract infection and whether markers of inflammation predicted the 25(OH)D concentration. Children aged 2–35 months with severe (n = 43) and non-severe (n = 387) community-acquired, WHO-defined pneumonia were included. 25(OH)D concentration and inflammatory markers (cytokines, chemokines, and growth factors) were measured in plasma during the acute phase and 14, 45, and 90 days later. Predictors for 25(OH)D concentrations were identified in multiple linear regression models. Mean 25(OH)D concentration during the acute phase and after recovery (14, 45, and 90 days) was 84.4 nmol/L ± 33.6, and 80.6 ± 35.4, respectively. None of the inflammatory markers predicted 25(OH)D concentration in the multiple regression models. Age was the most important predictor for 25(OH)D concentration, and there were no differences in 25(OH)D concentrations during illness and after 14, 45, and 90 days when adjusting for age. Infection and inflammation did not alter the 25(OH)D concentration in young children with acute lower respiratory tract infections. PMID:28106720

  2. Blood vitamin D(3) metabolite concentrations of adult female bearded dragons (Pogona vitticeps) remain stable after ceasing UVb exposure.

    PubMed

    Oonincx, D G A B; van de Wal, M D; Bosch, G; Stumpel, J B G; Heijboer, A C; van Leeuwen, J P T M; Hendriks, W H; Kik, M

    2013-07-01

    Vitamin D deficiency can lead to several health problems collectively called metabolic bone disease (MBD). One commonly kept reptile species prone to develop MBD if managed incorrectly is the bearded dragon (Pogona vitticeps). This study aimed to determine the extent to which adult female bearded dragons fed a diet low in vitamin D can use stored vitamin D and its metabolites to maintain plasma 25(OH)D(3) and 1,25(OH)(2)D(3) concentrations after discontinuing UVb exposure. Blood samples of healthy adult female bearded dragons, exposed to UVb radiation for over 6 months were collected (day 0) after which UVb exposure was discontinued for 83 days and blood was collected. Blood plasma was analysed for concentrations of total Ca, total P, ionized Ca, uric acid, 25(OH)D(3) and 1,25(OH)(2)D(3). There was no significant change in plasma 25(OH)D(3) and 1,25(OH)(2)D(3) concentrations during the study. While total Ca and P in whole blood was found to significantly decrease over time (P < 0.0088 and 0.0016, respectively), values were within the reference range. Plasma ionized Ca tended (P = 0.0525) to decrease during the study. Adult female bearded dragons, previously exposed to UVb, are able to maintain blood vitamin D metabolite concentrations when UVb exposure is discontinued for a period of up to 83 days.

  3. Photoaffinity labeling of the rat plasma vitamin D binding protein with (26,27-3H)-25-hydroxyvitamin D3 3 beta-(N-(4-azido-2-nitrophenyl)glycinate)

    SciTech Connect

    Ray, R.; Holick, S.A.; Hanafin, N.; Holick, M.F.

    1986-08-26

    It is well recognized that the vitamin D binding protein (DBP) is important for the transport of vitamin D, 25-hydroxyvitamin D (25-OH-D), and its metabolites. In an attempt to better understand the molecular-binding properties of this ubiquitous protein, we designed and synthesized a photoaffinity analogue of 25-OH-D3 and its radiolabeled counterpart. This analogue, 25-hydroxyvitamin D3 3 beta-(N-(4-azido-2-nitrophenyl)glycinate) (25-OH-D3-ANG), was recognized by the rat DBP and was about 10 times less active than 25-OH-D3 in terms of binding. Incubation of (/sup 3/H)25-OH-D3 or (/sup 3/H)25-OH-D3-ANG with rat DBP revealed that both compounds were specifically bound to a protein with a sedimentation coefficient of 4.1 S. Each was displaced with a 500-fold excess of 25-OH-D3. When (/sup 3/H)25-OH-D3-ANG was exposed to UV radiation in the presence of rat DBP followed by the addition of a 500-fold excess of 25-OH-D3, there was no displacement of tritium from the 4.1S peak. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis autoradiographic analysis of (/sup 3/H)25-OH-D3-ANG exposed to UV radiation in the presence of rat DBP followed by the addition of a 500-fold excess of 25-OH-D3 revealed one major band with a molecular weight of 52 000. These data provide strong evidence that (/sup 3/H)25-OH-D3-ANG was covalently linked to the rat DBP. This photoaffinity probe should provide a valuable tool for the analysis of the binding site on this transport protein.

  4. Vitamin D Levels Are Associated with Expression of SLE, but Not Flare Frequency

    PubMed Central

    Squance, Marline L.; Reeves, Glenn E. M.; Tran, Huy A.

    2014-01-01

    This study explores links between vitamin D deficiency (25(OH)D = 50 nmol/L) and serological autoimmunity (ANA > 1 : 80) and frequency of self-reported flares (SRF) in participants with clinical autoimmunity (SLE). 25(OH)D levels of 121 females were quantified and compared. The cohort consisted of 80 ACR defined SLE patients and 41 age and sex matched controls. Association analysis of log2 (25(OH)D) levels and ANA 80 positivity was undertaken via two-sample t-tests and regression models. Significant differences were found for 25(OH)D levels (mean: control 74 nmol/L (29.5 ng/ml); SLE 58 nmol/L (23.1 ng/ml), P = 0.04), 25(OH)D deficiency (P = 0.02). Regression models indicate that, for a twofold rise in 25(OH)D level, the odds ratio (OR) for ANA-positivity drops to 36% of the baseline OR. No link was found between SRF-days and 25(OH)D levels. Our results support links between vitamin D deficiency and expression of serological autoimmunity and clinical autoimmunity (SLE). However, no demonstrable association between 25(OH)D and SRF was confirmed, suggesting independent influences of other flare-inducing factors. Results indicate that SLE patients have high risk of 25(OH)D deficiency and therefore supplementation with regular monitoring should be considered as part of patient management. PMID:25506363

  5. Vitamin D insufficiency and schizophrenia risk: evaluation of hyperprolinemia as a mediator of association.

    PubMed

    Clelland, James D; Read, Laura L; Drouet, Valérie; Kaon, Angela; Kelly, Alexandra; Duff, Karen E; Nadrich, Robert H; Rajparia, Amit; Clelland, Catherine L

    2014-06-01

    25-Hydroxyvitamin D (25(OH)D) deficits have been associated with schizophrenia susceptibility and supplementation has been recommended for those at-risk. Although the mechanism by which a deficit confers risk is unknown, vitamin D is a potent transcriptional modulator and can regulate proline dehydrogenase (PRODH) expression. PRODH maps to chromosome 22q11, a region conferring the highest known genetic risk of schizophrenia, and encodes proline oxidase, which catalyzes proline catabolism. l-Proline is a neuromodulator at glutamatergic synapses, and peripheral hyperprolinemia has been associated with decreased IQ, cognitive impairment, schizoaffective disorder, and schizophrenia. We investigated the relationship between 25(OH)D and schizophrenia, comparing fasting plasma 25(OH)D in 64 patients and 90 matched controls. We then tested for a mediating effect of hyperprolinemia on the association between 25(OH)D and schizophrenia. 25(OH)D levels were significantly lower in patients, and 25(OH)D insufficiency associated with schizophrenia (OR 2.1, adjusted p=0.044, 95% CI: 1.02-4.46). Moreover, 25(OH)D insufficient subjects had three times greater odds of hyperprolinemia than those with optimal levels (p=0.035, 95% CI: 1.08-8.91), and formal testing established that hyperprolinemia is a significantly mediating phenotype that may explain over a third of the effect of 25(OH)D insufficiency on schizophrenia risk. This study presents a mechanism by which 25(OH)D insufficiency confers risk of schizophrenia; via proline elevation due to reduced PRODH expression, and a concomitant dysregulation of neurotransmission. Although definitive causality cannot be confirmed, these findings strongly support vitamin D supplementation in patients, particularly for those with elevated proline, who may represent a large subgroup of the schizophrenia population.

  6. Vitamin D status among immigrant mothers from Pakistan, Turkey and Somalia and their infants attending child health clinics in Norway.

    PubMed

    Madar, Ahmed A; Stene, Lars C; Meyer, Haakon E

    2009-04-01

    High prevalences of vitamin D deficiency have been reported in non-Western immigrants moving to Western countries, including Norway, but there is limited information on vitamin D status in infants born to immigrant mothers. We aimed to describe the vitamin D status and potentially correlated factors among infants aged 6 weeks and their mothers with Pakistani, Turkish or Somali background attending child health clinics in Norway. Eighty-six healthy infants and their mothers with immigrant background were recruited at the routine 6-week check-up at nine centres between 2004 and 2006. Venous or capillary blood was collected at the clinics from the mother and infant, and serum separated for analysis of 25-hydroxyvitamin D (s-25(OH)D) and intact parathyroid hormone (s-iPTH). The mean maternal s-25(OH)D was 25.8 nmol/l, with 57 % below 25 nmol/l and 15 % below 12.5 nmol/l. Of the mothers, 26 % had s-iPTH>5.7 pmol/l. For infants, mean s-25(OH)D was 41.7 nmol/l, with 47 % below 25 nmol/l and 34 % below 12.5 nmol/l. s-25(OH)D was considerably lower in the thirty-one exclusively breast-fed infants (mean 11.1 nmol/l; P < 0.0001). Use of vitamin D supplements and education showed a positive association with maternal s-25(OH)D. There was no significant association between mother's and child's s-25(OH)D, and no significant ethnic or seasonal variation in s-25(OH)D for mothers or infants. In conclusion, there is widespread vitamin D deficiency in immigrant mothers and their infants living in Norway. Exclusively breast-fed infants who did not receive vitamin D supplements had particularly severe vitamin D deficiency.

  7. [Treatment of vitamin D deficiency in the general population and in patients with chronic kidney disease].

    PubMed

    Mozzillo, Giusi Rosaria; Scognamiglio, Bernadette; Russo, Domenico

    2015-01-01

    Vitamin D is an essential micronutrient for humans. Vitamin D functions are not limited to the regulation of bone; it plays many pleiotropic effects due to ubiquitous distribution of VDR (Vitamin D Receptor). The vitamin D deficiency (defined as plasma levels of 25 - OH - vitamin D < 30 ng / ml) is now a public health problem worldwide. It is therefore essential to define protocols for supplementation of vitamin D in the general population and in patients with Chronic Kidney Disease and indications on the use of different Vitamins D available.

  8. Serum Vitamin D, Vitamin D Binding Protein, and Risk of Colorectal Cancer

    PubMed Central

    Anic, Gabriella M.; Weinstein, Stephanie J.; Mondul, Alison M.; Männistö, Satu; Albanes, Demetrius

    2014-01-01

    Background We previously reported a positive association between serum 25-hydroxyvitamin D (25(OH)D) and colorectal cancer risk. To further elucidate this association, we examined the molar ratio of 25(OH)D to vitamin D binding protein (DBP), the primary 25(OH)D transport protein, and whether DBP modified the association between 25(OH)D and colorectal cancer risk. Methods In a nested case-control study within the Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study, controls were 1∶1 matched to 416 colorectal cancer cases based on age and date of blood collection. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) for quartiles of 25(OH)D, DBP, and the molar ratio of 25(OH)D:DBP, a proxy for free, unbound circulating 25(OH)D. Results Comparing highest to lowest quartiles, DBP was not associated with colorectal cancer risk (OR = 0.91; 95% CI: 0.58, 1.42, p for trend  = 0.58); however, a positive risk association was observed for the molar ratio of 25(OH)D:DBP (OR = 1.44; 95% CI: 0.92, 2.26, p for trend  = 0.04). In stratified analyses, the positive association between 25(OH)D and colorectal cancer was stronger among men with DBP levels above the median (OR = 1.89; 95% CI: 1.07, 3.36, p for trend  = 0.01) than below the median (OR = 1.20; 95% CI: 0.68, 2.12, p for trend  = 0.87), although the interaction was not statistically significant (p for interaction  = 0.24). Conclusion Circulating DBP may influence the association between 25(OH)D and colorectal cancer in male smokers, with the suggestion of a stronger positive association in men with higher DBP concentrations. This finding should be examined in other populations, especially those that include women and non-smokers. PMID:25036524

  9. Single nucleotide polymorphisms in the vitamin D pathway associating with circulating concentrations of vitamin D metabolites and non-skeletal health outcomes: Review of genetic association studies.

    PubMed

    Jolliffe, David A; Walton, Robert T; Griffiths, Christopher J; Martineau, Adrian R

    2016-11-01

    Polymorphisms in genes encoding proteins involved in vitamin D metabolism and transport are recognised to influence vitamin D status. Syntheses of genetic association studies linking these variants to non-skeletal health outcomes are lacking. We therefore conducted a literature review to identify reports of statistically significant associations between single nucleotide polymorphisms (SNP) in 11 vitamin D pathway genes (DHCR7, CYP2R1, CYP3A4, CYP27A1, DBP, LRP2, CUB, CYP27B1, CYP24A1, VDR and RXRA) and non-bone health outcomes and circulating levels of 25-hydroxyvitamin D (25[OH]D and 1,25-dihydroxyvitamin D (1,25[OH]2D). A total of 120 genetic association studies reported positive associations, of which 44 investigated determinants of circulating 25(OH)D and/or 1,25(OH)2D concentrations, and 76 investigated determinants of non-skeletal health outcomes. Statistically significant associations were reported for a total of 55 SNP in the 11 genes investigated. There was limited overlap between genetic determinants of vitamin D status and those associated with non-skeletal health outcomes: polymorphisms in DBP, CYP2R1 and DHCR7 were the most frequent to be reported to associate with circulating concentrations of 25(OH)D, while polymorphisms in VDR were most commonly reported to associate with non-skeletal health outcomes, among which infectious and autoimmune diseases were the most represented.

  10. A pilot randomized, controlled trial of vitamin D repletion to determine if endothelial function improves in patients with systemic lupus erythematosus

    PubMed Central

    Kamen, Diane L; Oates, Jim

    2015-01-01

    The endothelium is important not only in regulating vascular tone but also in modulating inflammation. Patients with systemic lupus erythematosus (SLE) have deficits in these endothelial functions. Vitamin D is a nuclear hormone that regulates vascular endothelial nitric oxide synthase activity and expression. Many SLE patients have insufficient levels of vitamin D. The effect of this hormone on vascular endothelial function in SLE patients is not known. This study was designed to determine the effect size of repleting vitamin D levels on endothelial function in patients with SLE and vitamin D deficiency. SLE patients with 25(OH) vitamin D (25(OH)D) levels < 20 ng/ml were randomized to oral vitamin D3 (D3) doses that did or did not raise 25(OH)D levels to ≥ 32 ng/ml. Endothelial function was measured with flow-mediated dilation (FMD) before and after 16 weeks of vitamin D3 supplementation. Half of those who achieved 25(OH)D levels of ≥32 ng/ml experienced increases in FMD, while none of those with continued low 25(OH)D levels did. Those with increases in FMD had significantly higher final 25(OH)D levels. Using the effect size from this study, future studies designed to test the effect of repleting 25(OH)D on FMD in vitamin D deficient SLE patients will require 35 patients in each group. These results suggest a potential role for vitamin D in SLE-related endothelial dysfunction and that an adaptive multi-arm treat-to-target serum level trial design may increase the efficiency and likelihood of success of such a study. PMID:26351776

  11. Vitamin D deficiency is associated with anaemia among African Americans in a US cohort.

    PubMed

    Smith, Ellen M; Alvarez, Jessica A; Martin, Greg S; Zughaier, Susu M; Ziegler, Thomas R; Tangpricha, Vin

    2015-06-14

    Vitamin D deficiency is highly prevalent in the US population and is associated with numerous diseases, including those characterised by inflammatory processes. We aimed to investigate the link between vitamin D status and anaemia, hypothesising that lower vitamin D status would be associated with increased odds of anaemia, particularly anaemia with inflammation. A secondary aim was to examine the effects of race in the association between vitamin D status and anaemia. We conducted a cross-sectional analysis in a cohort of generally healthy adults in Atlanta, GA (n 638). Logistic regression was used to evaluate the association between vitamin D status and anaemia. Serum 25-hydroxyvitamin D (25(OH)D) < 50 nmol/l (compared to 25(OH)D ≥ 50 nmol/l) was associated with anaemia in bivariate analysis (OR 2·64, 95% CI 1·43, 4·86). There was significant effect modification by race (P= 0·003), such that blacks with 25(OH)D < 50 nmol/l had increased odds of anaemia (OR 6·42, 95% CI 1·88, 21·99), v. blacks with 25(OH)D ≥ 50 nmol/l, controlling for potential confounders; this association was not apparent in whites. When categorised by subtype of anaemia, blacks with 25(OH)D < 50 nmol/l had significantly increased odds of anaemia with inflammation than blacks with serum 25(OH)D ≥ 50 nmol/l (OR 8·42, 95% CI 1·96, 36·23); there was no association with anaemia without inflammation. In conclusion, serum 25(OH)D < 50 nmol/l was significantly associated with anaemia, particularly anaemia with inflammation, among blacks in a generally healthy adult US cohort.

  12. Low Maternal Vitamin D Status during the Second Trimester of Pregnancy: A Cross-Sectional Study in Wuxi, China

    PubMed Central

    Xiao, Jian-Ping; Zang, Jia; Pei, Jing-Jing; Xu, Fei; Zhu, Yan; Liao, Xiang-Peng

    2015-01-01

    Background Vitamin D deficiency is common in pregnant women, but an optimal serum vitamin D level during pregnancy has not been determined and remains an area of active research. Vitamin D data from large populations of pregnant Chinese women are still limited. Objective To evaluate the vitamin D status of women in Eastern China during the second trimester of pregnancy. Methods A hospital-based, cross-sectional, observational study. Serum 25-hydroxyvitamin D [25(OH)D] concentration was measured in samples from 5823 pregnant women in Wuxi City, China (latitude: 31.5o N), from January 2011 to June 2012. Results The median serum 25(OH)D concentration was 34.0 nmol/L [2.5 nmol/L 25(OH)D = 1 ng/mL 25(OH)D]. Vitamin D deficiency [defined as 25(OH)D < 30 nmol/L according to the Institute of Medicine (National Academy of Sciences, Washington, D.C., USA)] or inadequacy [25(OH)D of 30–49.9 nmol/L] was identified in 40.7% and 38.0% of the women, respectively. Only 0.9% had a 25(OH)D level ≥ 80.0 nmol/L, which is the concentration recommended as adequate by the Endocrine Society (Washington, D.C., USA). Compared with older women, younger women were more likely to be deficient in vitamin D. There were significant differences in the 25(OH)D levels according to season. The 25(OH)D levels reached peak values in September and were correlated with (r = 0.337, P < 0.001), and fluctuated with, average monthly air temperatures. Conclusions There is a high prevalence of Vitamin D deficiency among pregnant Chinese women, and 25(OH)D levels varied according to season and air temperature. The results of this study also suggest that currently there is a big gap between the levels of Vitamin D detected in pregnant Chinese women and the levels recommended by the Endocrine Society. PMID:25659105

  13. Pharmacokinetics of High-Dose Weekly Oral Vitamin D3 Supplementation during the Third Trimester of Pregnancy in Dhaka, Bangladesh

    PubMed Central

    Roth, Daniel E.; Al Mahmud, Abdullah; Raqib, Rubhana; Akhtar, Evana; Black, Robert E.; Baqui, Abdullah H.

    2013-01-01

    A pharmacokinetic study was conducted to assess the biochemical dose-response and tolerability of high-dose prenatal vitamin D3 supplementation in Dhaka, Bangladesh (23°N). Pregnant women at 27–30 weeks gestation (