[Role of vitamin E in regulation of cholecalciferol hydroxylation in hypovitaminosis D and hypervitaminosis D].
It is established, that dose-dependent influence of vitamin E on vitamin D3 metabolism, is conditioned by degree of cholecalciferol sufficiency. Under a condition of D-hypovitaminosis, contents of 25OHD3 in blood serum is 2-fold reduced and vitamin D3 25-hydroxylase enzymes activity increased in rat hepatocytes. Vitamin E (0.726-7.26 IU) significantly stimulated the effect of vitamin D3 (40 IU) in animals with D-hypovitaminosis and led to further increase of 25OHD3 content in the blood serum and activity of vitamin D3 25-hydroxylase enzymes in hepatocytes. In D-hypervitaminosis the contents of 25OHD3 in blood serum was more than 3-fold increased and vitamin D3 25-hydroxylase enzymes activity was inhibited. Vitamin E (0,726-7,26 IU) lowered the vitamin D toxicity, decreased contents of 25OHD3 in blood serum and activity of vitamin D3 25-hydroxylase enzymes in hepatocytes. High doses of vitamin E (36.3 IU) under these conditions demonstrated negative effect on vitamin D3 metabolism. The mechanism of vitaminE participation in the vitamin D3 metabolism under D-hypovitaminosis and D-hypervitaminosis may be its influence on the activity of different vitamin D3 25-hydroxylase systems of hepatocytes.
Apukhovs'ka
L I
LI
Velykyĭ
M M
MM
Lotots'ka
O Iu
OIu
Khomenko
A V
AV
D000818:Animals; D002762:Cholecalciferol / Q000008:administration & dosage / Q000378:metabolism*; D053493:Cholestanetriol 26-Monooxygenase / Q000097:blood*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006900:Hydroxylation; D008297:Male; D051381:Rats; D014808:Vitamin D Deficiency / Q000097:blood / Q000378:metabolism*; D014810:Vitamin E / Q000494:pharmacology*
D014810:Vitamin E; D002762:Cholecalciferol; D053493:Cholestanetriol 26-Monooxygenase