Environmental and Nutritional Influences on Plasma 25-Hydroxyvitamin D Concentration and Calcium Metabolism in Man

1977 ◽  
pp. 595-606
Keyword(s):  
Calcium Metabolism ◽  
Hydroxyvitamin D ◽  
Nutritional Influences ◽  
25 Hydroxyvitamin D

scholarly journals Vitamin D Supplementation in Sarcoidosis: A Double-Edged Sword

2021 ◽  
Author(s):  
Rishikesh Chandran ◽  
Lakshmi Nagendra ◽  
Shrikrishna Acharya ◽  
Giridhar Belur Hosmane ◽  
Vijith Shetty ◽  
...  
Keyword(s):  
Vitamin D ◽  
Disease Activity ◽  
Bone Health ◽  
Calcium Metabolism ◽  
Vitamin D Supplementation ◽  
Osteoporosis Prevention ◽  
Hydroxyvitamin D ◽  
Severe Hypercalcemia ◽  
25 Hydroxyvitamin D

AbstractSarcoidosis is complicated by disordered vitamin D and calcium metabolism, which has important implications on disease activity and bone health. Although the majority of the patients with sarcoidosis are typically deficient in 25-hydroxyvitamin D, repletion of vitamin D is controversial in light of the hypercalcemia risk. Presently, there are no clear guidelines regarding vitamin D supplementation as a part of osteoporosis prevention in patients with vitamin D deficiency and sarcoidosis. We report a patient with sarcoidosis who presented with severe hypercalcemia following vitamin D supplementation and review the debated role of vitamin D supplementation in vitamin D-deficient sarcoid patients.

Balancing Altered Calcium Metabolism with Bone Health in Sarcoidosis

2020 ◽  
Vol 41 (05) ◽  
pp. 618-625
Author(s):  
Ying Zhou ◽  
Elyse E. Lower
Keyword(s):  
Kidney Stones ◽  
Bone Health ◽  
Calcium Metabolism ◽  
Bone Fragility ◽  
Vitamin D Supplementation ◽  
Treatment Of Osteoporosis ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D ◽  
Low Levels ◽  
Increased Activity

AbstractAbnormal calcium metabolism in sarcoidosis patients can lead to hypercalcemia, hypercalciuria, and kidney stones. Hypercalcemia in sarcoidosis is usually due to increased activity of 1α-hydroxylase in macrophages of pulmonary granulomata, resulting in low levels of 25-hydroxyvitamin D and high levels of calcitriol. Vitamin D supplementation may be dangerous for some sarcoidosis patients and is recommended only for those with decreased 25-hydroxyvitamin D and reduced or normal calcitriol level. Diagnosis, treatment of osteoporosis, and maintenance of bone health are complex issues for sarcoidosis patients. An approach to diagnosis and treatment of bone fragility is presented.

scholarly journals Investigation of calcium metabolism in patients with coronary heart disease complicated by chronic heart failure, stage ii-a

2018 ◽  
Vol 17 (3) ◽  
pp. 395-401
Author(s):  
Pohoretska Khrystyna ◽  
Patskan Liudmyla ◽  
Stoikevych Halyna ◽  
Andriy Miz ◽  
Marushchak Mariya ◽  
...  
Keyword(s):  
Heart Failure ◽  
Coronary Heart Disease ◽  
Heart Disease ◽  
Chronic Heart Failure ◽  
Calcium Metabolism ◽  
Stage Ii ◽  
Ionized Calcium ◽  
Mineral Density ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D

Objective: This study aims to to investigate calcium metabolism indices and bone mineralization in patients with coronary heart disease complicated by stage II-A chronic heart failure.Materials and Methods: The study involved 33 men with coronary heart disease (CHD) complicated by Stage II-A chronic heart failure (according to the classification by N.D. Strazhesko, V.H. Vasilenko and G.F. Lung (1935). Bone mineral density was measured using dual energy x-ray densitometry of lumbar region of spine. The level of 25-hydroxyvitamin D (25(ОН)D) has been detected by ELISA method using commercial Vitamin D3 screening kit (Switzerland). The level of ionized calcium was measuring by ion selective method using analyser of electrolytes AEK-01 (QuertiMed, Ukraine).Results and Discussion: Structural and functional changes of bone tissue of the lumbar spine have been found in 49,2 percent patients with coronary heart disease complicated by Stage II-A chronic heart failure, in particular, I stage of osteopenia – in 44,6 %, II stage of osteopenia – in 27,7 %, III stage of osteopenia – in 10,8 % and osteoporosis – in 16,9 %. It was established the same type of downward trend for BMD decreasing in L1 of patients with different stages of osteopenia, but in case of osteoporosis mineralization decreased equally in all vertebrae. The analysis of calcium metabolism indices indicate that concentration of ionized calcium significantly decreased in patients with CHD complicated by Stage II-A chronic heart failure vs control (1.26±0.02 mmol/l) by 11.1 % (I stage of osteopenia), 18.3 % (II stage of osteopenia) and 31.7 % (III stage of osteopenia). Similar tendency was observed towards concentration of 25(ОН)D.Conclusion: In patients with CHD complicated by Stage II-A chronic heart failure we have established statistically significant decrease in serum level of ionized calcium and 25-hydroxyvitamin D concentration. However, we didn’t find the relationship between serum calcium, 25-hydroxyvitamin D concentration and bone mineral density. Structural and functional changes of bone tissue of the lumbar spine have been found in 49,2 percent patients with coronary heart disease complicated by Stage II-A chronic heart failure. It was established the same type of downward trend for BMD decreasing in L1 of patients with different stages of osteopenia, but in case of osteoporosis mineralization decreased equally in all vertebrae.Bangladesh Journal of Medical Science Vol.17(3) 2018 p.395-401

Evidence of a probable role for 25-hydroxyvitamin D in the regulation of human calcium metabolism

2009 ◽  
Vol 3 (5) ◽  
pp. 489-495 ◽  
Author(s):  
Norman H. Bell ◽  
Sol Epstein ◽  
Judith Shary ◽  
Virginia Greene ◽  
Mary Joan Oexmann ◽  
...  
Keyword(s):  
Calcium Metabolism ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D ◽  
Probable Role

Regulation of 25-hydroxyvitamin D3 metabolism in chick embryo

1987 ◽  
Vol 252 (1) ◽  
pp. E38-E43
Author(s):  
R. T. Turner ◽  
J. S. Graves ◽  
N. H. Bell
Keyword(s):  
Enzyme Activity ◽  
Chick Embryo ◽  
Calcium Metabolism ◽  
Time Course ◽  
Specific Activity ◽  
Plasma Calcium ◽  
Chick Embryos ◽  
Total Plasma ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D

We investigated the time course of the development of renal 25-hydroxyvitamin D-1-hydroxylase and 25-hydroxyvitamin D-24-hydroxylase in chick embryos grown in the presence and absence of the eggshell. In embryos with the eggshell, the specific activity (SA) of 25-hydroxyvitamin D-1-hydroxylase in kidney homogenates increased from 0.68 fmol X min-1 X mg protein-1 at 12 days of gestation to a peak of 2.55 +/- 0.50 fmol X min-1 X mg-1 protein-1 at 17 days. In contrast, the SA of 25-hydroxyvitamin D-24-hydroxylase decreased from 2.5 fmol X min-1 X mg protein-1 to 0.90 +/- 0.25 fmol X min-1 X mg protein-1 during the interval. The total plasma calcium was significantly reduced in embryos without shells at 14 to 15 days of gestation (1.1 +/- 0.1 mM, mean +/- SE) compared with normal embryos of the same gestation (2.3 +/- 0.3 mM, P less than 0.002). In embryos without the eggshell, renal 25-hydroxyvitamin D-1-hydroxylase increased from 6.0 to 8.2 +/- 0.6 fmol X min-1 X mg protein-1 at 17 days of gestation and was from four- to sixfold higher than corresponding enzymatic activities for intact embryos. The increased enzyme activity resulting from loss of the eggshell was due to an increase in Vmax. The findings indicate that renal 25-hydroxyvitamin D-1-hydroxylase and 25-hydroxyvitamin D-24-hydroxylase in the chick embryo exhibit activity and show a large capacity for regulation in response to changes in calcium metabolism.

Studies on the Regulation of Calcium Metabolism in Neonatal: Period: Plasma 25-Hydroxyvitamin D and Calcium

1978 ◽  
Vol 20 (1) ◽  
pp. 70-70
Author(s):  
Tsunesuke Shimotsuji ◽  
Makoto Ishida ◽  
Yoshiki Seina ◽  
Tsuneyasu Ishii ◽  
Chiiko Ikehara ◽  
...  
Keyword(s):  
Calcium Metabolism ◽  
Neonatal Period ◽  
Hydroxyvitamin D ◽  
25 Hydroxyvitamin D

Hypergravity modulates vitamin D receptor target gene mRNA expression in mice

2009 ◽  
Vol 297 (3) ◽  
pp. E728-E734 ◽  
Author(s):  
Michiyasu Ishizawa ◽  
Ken-ichi Iwasaki ◽  
Shigeaki Kato ◽  
Makoto Makishima
Keyword(s):  
Vitamin D ◽  
Mrna Expression ◽  
Vitamin D Receptor ◽  
Calcium Metabolism ◽  
Target Genes ◽  
Health Concern ◽  
Hydroxyvitamin D ◽  
Icr Mice ◽  
Expression Of Genes ◽  
25 Hydroxyvitamin D

The possibility of pathological calcium metabolism is a critical health concern introduced by long-term space travel. Because vitamin D plays an important role in calcium homeostasis, we evaluated the effects of hypergravity on the expression of genes involved in vitamin D and calcium metabolism in ICR mice. When exposed to 2G hypergravity for 2 days, the mRNA expression of renal 25-hydroxyvitamin D 24-hydroxylase (Cyp24a1) was increased and that of 25-hydroxyvitamin D 1α-hydroxylase (Cyp27b1) was decreased. Although hypergravity decreased food intake and increased the expression of starvation-induced genes, the changes in Cyp24a1 and Cyp27b1 expression were not due to starvation, suggesting that hypergravity affects these genes directly. Hypergravity decreased plasma 1α,25-dihydroxyvitamin D3 levels in ICR mice, suggesting a consequence of decreased Cyp27b1 and increased Cyp24a1 expression. Although 1α-hydroxyvitamin D3 [1α(OH)D3] treatment induced the expression of vitamin D receptor (VDR) target genes in the kidney of 2G-exposed ICR mice to similar levels as controls, 1α(OH)D3 increased the intestinal expression of Cyp24a1 in ICR mice. Hypergravity-dependent changes of Cyp24a1 and Cyp27b1 expression were diminished in mice exposed to hypergravity for 14 days, which may represent an adaptation to hypergravity stress. Hypergravity exposure also increased Cyp24a1 expression in the kidney of C57BL/6J mice. We examined the effects of hypergravity on VDR-null mice and found that renal Cyp27b1 expression in VDR-null mice was decreased by hypergravity while renal Cyp24a1 expression was not detected in VDR-null mice. Thus hypergravity modifies the expression of genes involved in vitamin D metabolism.

Sign in / Sign up

Export Citation Format

Share Document