scholarly journals Rat adipose tissue rapidly accumulates and slowly releases an orally-administered high vitamin D dose

1998 ◽  
Vol 79 (6) ◽  
pp. 527-532 ◽  
Author(s):  
D. A. Janneke Brouwer ◽  
Jackelieng Van Beek ◽  
Harri Ferwerda ◽  
Astrid M. Brugman ◽  
Fiona R. M. van der Klis ◽  
...  

We investigated the effect of oral high-dose cholecalciferol on plasma and adipose tissue cholecalciferol and its subsequent release, and on plasma 25-hydroxyvitamin D (25(OH)D). Female Wistar rats (n 126) received 37·5 μg cholecalciferol/d for 14 d and were subsequently studied for a further 88 d. Two subgroups of eighteen rats each were fasted for 3 d immediately after treatment (days 14−17) and at the end of the study (days 98−101). During treatment, plasma cholecalciferol increased rapidly to reach a steady-state. Plasma 25(OH)D and adipose tissue cholecalciferol increased linearly for 1 - 2 d after treatment. Serum Ca and inorganic phosphate also increased. Subsequently half-lives of plasma cholecalciferol and 25(OH)D, and perirenal and subcutaneous adipose tissue were: 1·4, 22·5, 97·5 and 80·9 d respectively. Fasting, as compared with ad libitum feeding, caused increased plasma free fatty acids, weight loss up to 14% and increased adipose tissue cholecalciferol (nmol/g wet weight). It did not affect plasma cholecalciferol immediately after cholecalciferol treatment, but raised plasma 25(OH)D. Fasting at the end of the study decreased plasma cholecalciferol and increased plasma 25(OH)D. We conclude that orally-administered cholecalciferol rapidly accumulates in adipose tissue and that it is very slowly released while there is energy balance. Fasting causes preferential loss of triacylglycerols from adipose tissue, as opposed to cholecalciferol, but nevertheless augments plasma 25(OH)D. Adipose tissue may act as a ‘buffer to functional vitamin D status’ by preventing, to a certain extent, unregulated production of 25(OH)D from dietary vitamin D, and by slowly releasing vitamin D under fasting conditions.

2015 ◽  
Vol 18 (02) ◽  
pp. 1550008 ◽  
Author(s):  
Negin Masoudi Alavi ◽  
Mahla Madani ◽  
Mohsen Taghizadeh ◽  
Mohammad Reza Sharif

Purpose: To investigate the effect of weekly single high dose vitamin D supplementation on serum 25-hydroxyvitamin D [25(OH)D], and non-specific musculoskeletal pain in female nurses. Methods: In this prospective study in Kashan/Iran, from April 1, 2014, through September 30, 2014, the 150 nurses with vitamin D deficiency received the weekly pearls of 50,000 units of vitamin D3 for 10 weeks. The serum level of 25(OH)D was measured before and after supplement therapy. The subjects were also asked to complete the Extended Nordic Musculoskeletal Questionnaire. All analyses were conducted with SPSS version 16. Results: After 10 weeks of intervention there was [Formula: see text][Formula: see text]ng/mL increase in 25(OH)D. The 82 nurses (54.7%) had 25(OH)D in normal range, while the 68 nurses (45.3%) were still vitamin D deficient. Weight could explain 15.4% increase in 25(OH)D. Before intervention 135 (90%), of nurses reported musculoskeletal pain in at least one region, after intervention this number decreased to 72.7%. There was a statistically significant improvement in musculoskeletal pain in neck, shoulders, upper back, lower back, hips/tights, knees, and ankles/feet after intervention. Conclusions: The weekly single high dose of vitamin D for 10 weeks could resolve vitamin D deficiency in about half of the patients. Patients with non-specific musculoskeletal pain might benefit from vitamin D 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.


2015 ◽  
Vol 76 (3) ◽  
pp. 109-116 ◽  
Author(s):  
Banaz Al-Khalidi ◽  
Winnie Chiu ◽  
Dérick Rousseau ◽  
Reinhold Vieth

Purpose: To assess the bioavailability and safety of vitamin D3 from fortified mozzarella cheese baked on pizza. Methods: In a randomized, double-blind trial, 96 apparently healthy, ethnically diverse adults were randomized to consume 200 IU or 28 000 IU vitamin D3 fortified mozzarella cheese with pizza once weekly for a total of 8 weeks. Blood and urine samples were collected at baseline (week 1) and final (week 10) visits for serum 25-hydroxyvitamin D and other biochemical measures. The primary outcome compared serum 25-hydroxyvitamin D between groups at 10 weeks. The secondary outcome evaluated the safety of vitamin D dosing protocol as measured by serum and urine calcium, phosphate, creatinine, and serum parathyroid hormone (PTH). Results: Serum 25-hydroxyvitamin D increased by 5.1 ± 11 nmol/L in the low-dose group (n = 47; P = 0.003), and by 73 ± 22 nmol/L in the high-dose group (n = 49; P < 0.0001). None of the subjects in either group developed any adverse events during the supplementation protocol. Serum PTH significantly decreased in the high-dose group only (P < 0.05). Conclusions: Vitamin D3 is safe and bioavailable from fortified mozzarella cheese baked on pizza.


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.


2020 ◽  
Vol 5 (2) ◽  
pp. 32
Author(s):  
Jennifer B. Fields ◽  
Sina Gallo ◽  
Jenna M. Worswick ◽  
Deanna R. Busteed ◽  
Margaret T. Jones

Women athletes are at higher risk for bone diseases; yet, information on vitamin D status ((25(OH)D), vitamin D binding protein (VDBP), and bioavailable 25(OH)D is limited. Collegiate athletes (n = 36) from volleyball (WVB), basketball (WBB), and track and field (WTF) were measured for (25(OH)D), VDBP, and bioavailable 25(OH)D; body composition and bone mineral density (BMD); and skin pigmentation. Participants self-reported daily vitamin D intake and sun exposure. One-way analysis of variance analyzed mean differences in measures across sports. Linear regression examined relationships between 25(OH)D; VDBP; bioavailable 25(OH)D; and whole body, hip, and spine BMD. Participants’ (mean ± SD, 19.4 ± 1.4 years, 172.75 ± 8.21 cm, 70.9 ± 13.2 kg, and 22.9 ± 4.1% body fat) overall mean 25(OH)D was 70.5 ± 32.25 nmol/L, and 28% of participants were deemed inadequate and 61% below thresholds identified as sufficient for athletes. Although WBB athletes consumed higher (p = 0.007) dietary vitamin D (760.9 ± 484.2 IU/d) than WVB (342.6 ± 257.8) and WTF (402.3 ± 376.4) athletes did, there were no differences across sport in serum 25(OH)D. WVB and WTF had higher bioavailable 25(OH)D than WBB. No relationships existed between vitamin D status and body composition. Vitamin D inadequacy was identified among 1/3 of women indoor sport athletes. Consistent monitoring of vitamin D status and diet are recommended to sustain athlete health and sport performance.


2012 ◽  
Vol 201 (5) ◽  
pp. 360-368 ◽  
Author(s):  
Marie Kjærgaard ◽  
Knut Waterloo ◽  
Catharina E. A. Wang ◽  
Bjørg Almås ◽  
Yngve Figenschau ◽  
...  

AimsTo compare depressive symptoms in participants with low and high serum 25-hydroxyvitamin D (25(OH)D) levels and to examine whether supplementation with vitamin D3 would improve symptoms in those with low serum 25(OH)D levels.MethodParticipants with low 25(OH)D levels were randomised to either placebo or 40 000 IU vitamin D3 per week for 6 months. Individuals with high serum 25(OH)D levels were used as nested controls. Depressive symptoms were evaluated with the Beck Depression Inventory, Hospital Anxiety and Depression Scale, Seasonal Pattern Assessment Scale and Montgomery-Åsberg Depression Rating Scale. The study was registered at ClinicalTrials.gov (NCT00960232).ResultsParticipants with low 25(OH)D levels (n=230) at baseline were more depressed (P<0.05) than participants with high 25(OH)D levels (n=114). In the intervention study no significant effect of high-dose vitamin D was found on depressive symptom scores when compared with placebo.ConclusionsLow levels of serum 25(OH)D are associated with depressive symptoms, but no effect was found with vitamin D supplementation.


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