scholarly journals Discrimination in the metabolism of orally dosed ergocalciferol and cholecalciferol by the pig, rat and chick

1982 ◽  
Vol 204 (1) ◽  
pp. 185-189 ◽  
Author(s):  
R L Horst ◽  
J L Napoli ◽  
E T Littledike

Vitamin D-deficient pigs, rats and chicks were repleted with four daily oral doses of crystalline ergocalciferol (vitamin D2) and cholecalciferol (vitamin D3) containing equal concentrations of each. At 24 h after the last dose, the plasma of each species was analysed for vitamin D and 25-hydroxyvitamin D by standard methods. The mean (+/- S.D.) ratios of plasma cholecalciferol to ergocalciferol concentration were 1.5 +/- 0.1 (pig). 1.7 +/- 0.1 (rat) and 6.3 +/- 1.2 (chick). The mean ratios of plasma 25-hydroxycholecalciferol to 25-hydroxyergocalciferol concentration were 4.0 +/- 0.1 (pig), 0.4 +/- 0.02 (rat) and 10.7 +/- 3.4 (chick). The mean plasma cholecalciferol/ergocalciferol ratios for the 24,25-dihydroxy-, 25,26-dihydroxy- and 1,25-dihydroxy-derivatives in the pig were 2.6 +/- 0.6, 5.8 +/- 1.3 and 5.8 +/- 0.8 respectively. This is the first evidence that mammals other than the New World monkey, like birds, discriminate between ergocalciferol and cholecalciferol. These data, therefore, suggest that species discrimination between the different forms of vitamin D is probably a general phenomenon in mammals. Moreover, this is the first indication of a species (rat) that discriminates against a cholecalciferol metabolite in favour of an ergocalciferol metabolite. Species discrimination against particular forms of vitamin D may be important to the choice of experimental animal models for studying the regulation of vitamin D metabolism and may also be an important consideration in dietary vitamin supplementation.

2015 ◽  
Vol 114 (1) ◽  
pp. 144-151 ◽  
Author(s):  
Cuiling Xu ◽  
Ranawaka A. P. M. Perera ◽  
Yap-Hang Chan ◽  
Vicky J. Fang ◽  
Sophia Ng ◽  
...  

Vitamin D plays an important role in skeletal health throughout life. Some studies have hypothesised that vitamin D may reduce the risk of other diseases. Our study aimed to estimate age-specific and sex-specific serum 25-hydroxyvitamin D (25(OH)D) status and to identify the determinants of serum 25(OH)D status in Hong Kong, a subtropical city in southern China. In 2009–2010, households in Hong Kong were followed up to identify acute respiratory illnesses, and sera from 2694 subjects were collected in three to four different study phases to permit measurement of 25(OH)D levels at different times of the year. A questionnaire survey on diet and lifestyle was conducted among children, with simultaneous serum collection in April and May 2010. The mean of serum 25(OH)D levels in age groups ranged from 39 to 63 nmol/l throughout the year with the mean values in all age groups in spring below 50 nmol/l. Children aged 6–17 years, and girls and women had significantly lower serum 25(OH)D levels than adults, and boys and men, respectively (allP< 0·001). We estimated that serum 25(OH)D levels in Hong Kong followed a lagged pattern relative to climatic season by 5 weeks with lowest observed levels in early spring (March). For children aged 6–17 years, reporting a suntan, having at least 1 servings of fish/week and having at least 1 serving of eggs/week were independently associated with higher serum 25(OH)D levels. Adequate sunlight exposure and increased intake of dietary vitamin D could improve vitamin D status, especially for children and females in the winter and spring.


2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Carol L. Wagner ◽  
Cindy Howard ◽  
Thomas C. Hulsey ◽  
Ruth A. Lawrence ◽  
Sarah N. Taylor ◽  
...  

Objective. To examine the effectiveness of oral vitamin (400 IU) supplementation on the nutritional vitamin D status of breastfeeding infants.Design. As part of a larger ongoing vitamin D RCT trial of lactating women, infants of mothers assigned to control received 1 drop of 400 IU vitamin /day starting at one month of age. Infant 25(OH)D levels (mean S.D.) were measured by RIA at visits 1, 4, and 7.Results. The infant mean S.D. 25(OH)D at baseline was 16.0 9.3 ng/mL (range 1.0–40.8; ); 24 (72.7%) had baseline levels <20 ng/mL (consistent with deficiency). The mean levels increased to 43.6 14.1 (range 18.2–69.7) at 4 months and remained relatively unchanged at month 7: 42.5 12.1 ng/mL (range 18.9–67.2). The change in values between 1 and 4 months and 1 and 7 months was statistically significant , and despite a decrease in dose per kilogram, values were not significantly different between months 4 and 7 .Conclusions. Oral vitamin supplementation as an oil emulsion was associated with significant and sustained increases in 25(OH)D from baseline in fully breastfeeding infants through 7 months.


PEDIATRICS ◽  
1984 ◽  
Vol 73 (4) ◽  
pp. 538-542
Author(s):  
Yoshikazu Nishi ◽  
Sumio Hyodo ◽  
Kazunori Yoshimitsu ◽  
Kunihiko Sawano ◽  
Kanji Yamaoka ◽  
...  

The effect of calcitonin on plasma concentrations of 25-hydroxyvitamin D (25-OHD) and 1,25-dihydroxyvitamin D [1,25-(OH)2D] was studied in six patients with osteogenesis imperfecta. The mean pretreatment value of plasma 1,25-(OH)2D was significantly higher than the mean value of age-matched control subjects (P &lt; .05). High or normal plasma levels of 1,25-(OH)2D before calcitonin therapy were decreased after 1 month of therapy and remained normal thereafter in all six patients. Plasma 25-hydroxyvitamin D concentrations, which were normal before calcitonin injection, remained normal during calcitonin administration. These results indicate that there may be acute and chronic effects of calcitonin on vitamin D metabolism.


2021 ◽  
pp. 1-7
Author(s):  
Naomi Vather-Wu ◽  
Matthew D. Krasowski ◽  
Katherine D. Mathews ◽  
Amal Shibli-Rahhal

Background: Expert guidelines recommend annual monitoring of 25-hydroxyvitamin D (25-OHD) and maintaining 25-OHD ≥30 ng/ml in patients with dystrophinopathies. Objective: We hypothesized that 25-OHD remains stable and requires less frequent monitoring in patients taking stable maintenance doses of vitamin D. Methods: We performed a retrospective cohort study, using the electronic health record to identify 26 patients with dystrophinopathies with a baseline 25-OHD ≥30 ng/mL and at least one additional 25-OHD measurement. These patients had received a stable dose of vitamin D for ≥3 months prior to their baseline 25-OHD measurement and throughout follow-up. The main outcome measured was the mean duration time the subjects spent with a 25-OHD ≥30 ng/mL. Results: Only 19% of patients dropped their 25-OHD to <  30 ng/ml, with a mean time to drop of 33 months and a median nadir 25-OHD of 28 ng/mL. Conclusions: These results suggest that measurement of 25-OHD every 2–2.5 years may be sufficient in patients with a baseline 25-OHD ≥30 ng/mL and who are on a stable maintenance dose of vitamin D. Other patients may require more frequent assessments.


2017 ◽  
Vol 26 (1) ◽  
pp. 56-59
Author(s):  
Ivana Goluza ◽  
Jay Borchard ◽  
Nalin Wijesinghe ◽  
Kishan Wijesinghe ◽  
Nagesh Pai

Objectives: The objective of the current study was to examine the pathology test utilisation of 25-hydroxyvitamin D (25(OH)D) within an Australian inpatient psychiatric setting. Method: A retrospective audit of 300 random hospital files of those admitted as inpatients between Nov 2014 and Nov 2015 was undertaken. Data was quantitatively analysed and described. Results: The number of inpatients who had a vitamin D determination during their admission was 37/300 (12.33%). The mean vitamin D level of those tested was 51.63 nmol/l. Of those that were tested, 18/37 (48.6%) were mildly to moderately deficient. There was a statistically significant difference in age and length of stay between those that were and were not tested for vitamin D levels, p-value <0.001 and 0.017, respectively. In addition, a simple linear regression indicated a weak association between length of stay and vitamin D levels. Conclusion: This audit highlights vitamin D screening inadequacy. More research is recommended to establish tangible benefits of supplementation, while local practice provides valuable data for education and policy purposes.


2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S393-S393
Author(s):  
A Aksan ◽  
K Böttger ◽  
N Hein ◽  
Y Caicedo-Zea ◽  
I Diehl ◽  
...  

Abstract Background Vitamin D deficiency occurs frequently in patients with Crohn’s disease (CD) and ulcerative colitis (UC). While recent cohort studies support an association of vitamin D with important clinical parameters and outcomes in IBD, the complex interplay of inflammation with vitamin D metabolism in IBD poses a viscious circle. We sought to further illucidate the relation between inflammation and different vitamin D parameters. To the best our knowledge, this was the first study to focus on the relationship between vitamin D binding protein (VDBP), circulating total, free, and bioavailable 25-hydroxyvitamin D (25(OH)D), and inflammation, in adult IBD patients. Methods This was a comparative, single-centred, cross-sectional study in patients with IBD aged 18–65 years. Full blood count, transferrin, albumin and hsCRP were determined by standard methods. The presence/absence of inflammation was assessed based on serum hsCRP levels (cutoff &lt;5mg/l). VDBP levels were determined by ELISA, and 25(OH)D by LCMS. Free and bioavailable vitamin D levels were calculated using the validated formula. IBM SPSS version 25.0 was used for statistical analysis. Results In total, 129 subjects with IBD (70 male/59 female; 82 CD/47 UC; mean age 41.7 ± 12.6 years) were enrolled. Of these, 38/129 had inflammation (19 m/19 f; 26 CD/12 UC; 39.6 ± 12.9 years) while 91/129 had no inflammation (40 m/51 f; 56 CD/35 UC; 42.5 ± 12.5 years). Subjects with disease activity had significantly higher leukocyte, erythrocyte sedimentation rate (ESR) and hsCRP, but lower transferrin, transferrin saturation (TSAT) and albumin levels than those without inflammation (p &lt; 0.05). Average serum levels of 25(OH)D (24.6[6.8–54.8] vs. 26.4[5.0–74.4]ng/ml), free 25(OH)D (5.9[1.3–13.3] vs. 1.0[1.0–21.4]ng/ml) and bioavailable 25(OH)D(2.3 [0.1–4.7] vs. 2.4[0.5–19.5]ng/ml) were similar in patients with vs. without inflammation (p &gt; 0.05). However, VDBP levels were significantly higher in inflammatory conditions (359.6[252.2–530.6] mg/l vs. 327.4[183.5–560.3]mg/l; p &lt; 0.05) and showed a positive correlation with CRP levels (0.293, p &lt; 0.001). Ratio of free/total 25(OH)D correlated negatively with CRP levels (−0.282, p = 0.002). Conclusion High levels of circulating VDBP were associated with inflammatory activity. Moreover, free/total 25(OH)D ratio was inversely associated with inflammation. Other vitamin D parameters including total, free and bioavailable 25(OH)D showed no association with inflammation. These findings suggest that VDBP may play a bigger role than thought as a modulator of vitamin D and inflammation, and that simultaneous detection and investigation of plasma VDBP may provide additional insights into this complex interaction.


Metabolites ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 371 ◽  
Author(s):  
Emma A. Hurst ◽  
Natalie Z. Homer ◽  
Richard J. Mellanby

The demand for vitamin D analysis in veterinary species is increasing with the growing knowledge of the extra-skeletal role vitamin D plays in health and disease. The circulating 25-hydroxyvitamin-D (25(OH)D) metabolite is used to assess vitamin D status, and the benefits of analysing other metabolites in the complex vitamin D pathway are being discovered in humans. Profiling of the vitamin D pathway by liquid chromatography tandem mass spectrometry (LC-MS/MS) facilitates simultaneous analysis of multiple metabolites in a single sample and over wide dynamic ranges, and this method is now considered the gold-standard for quantifying vitamin D metabolites. However, very few studies report using LC-MS/MS for the analysis of vitamin D metabolites in veterinary species. Given the complexity of the vitamin D pathway and the similarities in the roles of vitamin D in health and disease between humans and companion animals, there is a clear need to establish a comprehensive, reliable method for veterinary analysis that is comparable to that used in human clinical practice. In this review, we highlight the differences in vitamin D metabolism between veterinary species and the benefits of measuring vitamin D metabolites beyond 25(OH)D. Finally, we discuss the analytical challenges in profiling vitamin D in veterinary species with a focus on LC-MS/MS methods.


2018 ◽  
Vol 39 (2) ◽  
pp. 260-265
Author(s):  
Yanhong Li ◽  
Yan Li ◽  
Xian Zhang ◽  
Lin Zhao ◽  
Liqin Chen ◽  
...  

Objectives: To determine the prevalence of vitamin D deficiency in 6- to 23-month-old children from 4 different ethnic groups, Han, Lisu, Hani, and Bai, in Yunnan Province of China. Methods: A large cohort of 938 young children aged 6 to 23 months who were living in Yunnan, China (23°28′-27°52′ N), were selected and recruited in this study. Venous-blood sampling was conducted in all the participants, and serum 25-hydroxyvitamin D [25(OH)D] levels were measured. The children’s physical status was measured. Results: General mean serum 25(OH)D level was 21.46 ± 7.95 ng/mL, which was obtained from a total of 938 cases. No significant difference was found in age, gender, height, and weight of participants from different ethnic groups. The mean 25(OH)D level was significantly lower in children of Lisu ethnic groups compared with that of Han and Hani participants, respectively ( P < .05). In addition, Bai children had lower 25(OH)D content than Hani children ( P < .001). Among the children with 25(OH)D sufficiency, the number of Lisu participants was significantly lower than Han children ( P < .001). Conclusion: The prevalence of vitamin D deficiency varied among the ethnically different children in Yunnan, China, and significantly fewer Lisu children maintained vitamin D sufficiency compared with other ethnic children. Recognizing these ethnic differences in treating children with vitamin D deficiency may improve the therapeutic outcome.


Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 743 ◽  
Author(s):  
Keiko Asakura ◽  
Norihito Etoh ◽  
Haruhiko Imamura ◽  
Takehiro Michikawa ◽  
Takahiro Nakamura ◽  
...  

Vitamin D insufficiency/deficiency is prevalent worldwide. We investigated the effect of vitamin D intake and ultraviolet ray (UV) exposure on serum vitamin D concentration in Japan. A total of 107 healthy adult participants were recruited from Hokkaido (43° N) and Kumamoto (33° N) prefectures. All participants undertook surveys in both summer and winter. Serum 25-hydroxyvitamin D (25(OH)D3) was examined, and vitamin D intake was assessed with a diet history questionnaire. UV exposure was measured with a wearable UV dosimeter. Regression analysis was performed to investigate the relationship between these factors, with covariates such as sun avoidance behavior. The prevalence of vitamin D insufficiency (serum 25(OH)D3; 12 ng/mL (30 nmol/L) ≤ and <20 ng/mL (50 nmol/L))/deficiency (<12 ng/mL) was 47.7% in summer and 82.2% in winter. UV exposure time was short in Kumamoto (the urban area), at 11.6 min in summer and 14.9 min in winter. In Hokkaido (the rural area), UV exposure time was 58.3 min in summer and 22.5 min in winter. Vitamin D intake was significantly associated with serum 25(OH)D3, and a 1 μg/1000kcal increase in intake was necessary to increase 25(OH)D3 by 0.88 ng/mL in summer and by 1.7 ng/mL in winter. UV exposure time was significantly associated with serum 25(OH)D3 in summer, and a 10 min increase in UV exposure time was necessary to increase 25(OH)D3 by 0.47 ng/mL. Although consideration of personal occupation and lifestyle is necessary, most Japanese may need to increase both vitamin D intake and UV exposure.


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