Intestinal metabolism and portal venous transport of 1,25(OH)2D3, 25(OH)D3, and vitamin D3 in the rat

1985 ◽  
Vol 248 (6) ◽  
pp. G633-G638 ◽  
Author(s):  
G. B. McDonald ◽  
K. H. Lau ◽  
A. L. Schy ◽  
J. E. Wergedal ◽  
D. J. Baylink
Keyword(s):  
Vitamin D ◽  
Vitamin D3 ◽  
High Performance ◽  
Average Rate ◽  
Venous Blood ◽  
Intestinal Metabolism ◽  
Dihydroxyvitamin D3 ◽  
1,25 Dihydroxyvitamin D3 ◽  
Polar Metabolites

We compared the intestinal absorption of three vitamin D3 sterols and tested the hypothesis that the intestine hydroxylates absorbed vitamin D and transports polar metabolites in portal venous blood. Micellar solutions containing 50 nmol of a radiolabeled vitamin D3 sterol (1,25-dihydroxyvitamin D3, 25-hydroxyvitamin D3, or vitamin D3) were placed in closed jejunal segments of rats prepared with lymphatic and mesenteric venous fistulas. Venous blood loss was replaced by infusion of donor rat blood into the saphenous vein. After 1-2 h the rats were killed, and intestinal homogenates, mesenteric blood, and lymph were analyzed. The average rate of absorption of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] was two- and fivefold higher than that of 25-hydroxyvitamin D3 [25(OH)D3] and vitamin D3 (D3), respectively. Transport of hydroxylated vitamin D sterols was primarily via the venous route; the average rate of venous transport of 1,25(OH)2D3 was 18.3 X 10(2) nmol X min-1 X g-1 compared with 8.8 X 10(2) for 25(OH)D3 and 0.13 X 10(2) for D3. High-performance liquid chromatography of intestinal and plasma extracts revealed that there was 25-hydroxylation of absorbed D3, 24- and putative 1-hydroxylation of absorbed 25(OH)D3, and prompt portal venous transport of all hydroxylated metabolites. When 1,25(OH)2D3 was infused into the lumen, the composition of radiolabeled sterols found in intestinal homogenates and mesenteric venous plasma was virtually identical to that of the infusate. These studies provide in vivo evidence for the intestinal metabolism of pharmacological quantities of absorbed vitamin D3 sterols and the prompt portal venous transport of more polar metabolites.

Rat renal 25-hydroxyvitamin D3 1- and 24-hydroxylases: their in vivo regulation

1984 ◽  
Vol 246 (2) ◽  
pp. E168-E173 ◽  
Author(s):  
Y. Tanaka ◽  
H. F. DeLuca
Keyword(s):  
Vitamin D ◽  
Inorganic Phosphorus ◽  
Hydroxylase Activity ◽  
Deficient Diet ◽  
Dihydroxyvitamin D3 ◽  
1,25 Dihydroxyvitamin D3 ◽  
Dietary Phosphorus ◽  
Low Calcium

The effects of thyroparathyroidectomy, parathyroid hormone, 1,25-dihydroxyvitamin D3, dietary calcium, dietary phosphorus, age, and sex on the renal 25-hydroxyvitamin D3 1- and 24-hydroxylases measured in vitro in rats have been studied. Thyroparathyroidectomy of vitamin D-deficient rats abolishes 25-hydroxyvitamin D3 1-hydroxylase activity, and administration of bovine parathyroid extract to the thyroparathyroidectomized rat restores diminished 1-hydroxylase activity. Both suppression and restoration of the enzyme activities require many hours (18-24 h) independent of rapid changes in serum calcium and inorganic phosphorus levels in response to these manipulations. Administration of 1,25-dihydroxyvitamin D3 to vitamin D-deficient rats suppresses 25-hydroxyvitamin D3 1-hydroxylase activity and stimulates 25-hydroxyvitamin D3 24-hydroxylase activity within 48 h. Rats maintained on a low-calcium or a low-phosphorus diet with a daily supplement of 20 IU vitamin D3 show high 25-hydroxyvitamin D3 1-hydroxylase activity and low 24-hydroxylase activity as compared with rats similarly treated but fed a diet containing adequate calcium or adequate phosphorus. When vitamin D-sufficient rats having suppressed renal 25-hydroxyvitamin D3 1-hydroxylase activity are placed on a low-calcium vitamin D-deficient diet for 7 days, the 1-hydroxylase activity is greatly stimulated in 6-wk-old rats but much less so in rats with advancing age.

Effects of vitamin D and diet magnesium on magnesium metabolism

1980 ◽  
Vol 239 (6) ◽  
pp. E515-E523 ◽  
Author(s):  
B. S. Levine ◽  
N. Brautbar ◽  
M. W. Walling ◽  
D. B. Lee ◽  
J. W. Coburn
Keyword(s):  
Vitamin D ◽  
Vitamin D3 ◽  
Tubular Reabsorption ◽  
Transport Processes ◽  
Separate Experiment ◽  
Dihydroxyvitamin D3 ◽  
Magnesium Metabolism ◽  
1,25 Dihydroxyvitamin D3 ◽  
24,25 Dihydroxyvitamin D3

Effects of 6-9 days of vitamin D3 (D3), 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], 24,25-dihydroxyvitamin D3 [24,25(OH)2D3], or 1,24,25-trihydroxyvitamin D3 [1,24,25(OH)3D3] on Mg metabolism were studied in vitamin D-deficient (-D) rats. Mg absorption expressed as percent intake increased with 1,25(OH)2D3 and 1,24,25(OH)3D3. Urinary Mg (UMg) increased with no change in serum Mg (SMg) or Mg balance. 1,25(OH)2D3 was threefold more potent than 1,24,25(OH)3D3 in raising serum Ca and Mg absorption. In a separate experiment in pair-fed rats given D3, 1,25-(OH)2D3, or 1,24,25(OH)3D3, the diet contained either 0.03 or 0.2% Mg; 1,25(OH)2D3 and D3 lowered SMg after 3 days; UMg increased after 24 h to remain elevated. D3 and 1,25(OH)2D3 augmented Mg absorption; feeding 0.2% Mg lowered Mg absorption in -D animals. All sterols augmented Mg absorption in -D rats; both the earlier action of 1,25(OH)2D3 and 1,24,25(OH)3D3 suggests that 1-hydroxylation is necessary. Suppressed Mg absorption with 0.2% Mg in -D rats suggests two transport processes, with one vitamin D dependent. Higher UMg with decreased SMg with 1,25(OH)2D3 suggests reduced tubular reabsorption.

Expression of the 1,25-dihydroxyvitamin D3-24-hydroxylase gene in rat intestine: Response to calcium, vitamin D3 and calcitriol administration in vivo

2009 ◽  
Vol 10 (8) ◽  
pp. 1148-1157 ◽  
Author(s):  
Jacques Lemay ◽  
Christian Demers ◽  
Geoffrey N. Hendy ◽  
Edgard E. Delvin ◽  
Marielle Gascon-Barré
Keyword(s):  
Vitamin D3 ◽  
Rat Intestine ◽  
Dihydroxyvitamin D3 ◽  
1,25 Dihydroxyvitamin D3 ◽  
Hydroxylase Gene

scholarly journals Cathelicidin, vitamin D3 dan imunitas terhadap tuberkulosis

2020 ◽  
Vol 20 (3) ◽  
Author(s):  
Yunita Arliny ◽  
Maryatun Hasan
Keyword(s):  
Vitamin D ◽  
Immune Response ◽  
Innate Immune Response ◽  
Vitamin D3 ◽  
Immune Cells ◽  
Active Form ◽  
Innate Immune ◽  
Dihydroxyvitamin D3 ◽  
1,25 Dihydroxyvitamin D3 ◽  
Natural Defense

Abstrak. Tuberkulosis (TB) merupakan salah satu penyakit infeksi yang menjadi masalah di dunia. Risiko untuk mendapatkan infeksi TB dipengaruhi oleh imunitas alamiah melawan mikobakteria. Peptida antimikroba merupakan salah satu barrier pertahanan alamiah. Cathelicidin adalah suatu peptida anti mikroba yang berperan pada proses imunitas terhadap TB. Cathelicidin Leusin Leusin-37 (LL-37) merupakan satu-satunya cathelicidin yang ada pada manusia dan dapat diekspresikan dari beberapa sel temasuk sel imun. Inducer Cathelicidin yang paling poten adalah 1,25-dihydroxyvitamin D3 yang merupakan bentuk aktif vitamin D 25(OH)D3. Tinjauan pustaka ini membahas tentang cathelicidin, vitamin D3 dam peranannya pada imunitas terhadap TB.Kata kunci: Cathelicidin, 1,25-dihydroxyvitamin D3, vitamin D 25(OH)2D3, imunitas, TuberkulosisAbstract. Tuberculosis is one of the most important infectious diseases worldwide. The susceptibility to this disease depends to great extent on the innate immune response against mycobacteria. Antimicrobial peptides are one of the natural defense barriers. Cathelicidin Leucine Leucine-37 (LL-37) is the only cathelicidin present in humans and synthesized by several cells including immune cells. The most effective inducer of Cathelicidin is 1,25-dihydroxyvitamin D3 (1,25(OH)2 D3), which is an active form of vitamin D 25(OH)D3. This review discusses cathelicidin, vitamin D3 and its role in immunity against TBKeywords: Cathelicidin, 1,25-dihydroxyvitamin D3, vitamin D 25(OH)D3, immunity, Tuberkulosis

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