vitamin-k-1 and carboxyethyl-hydroxychroman
vitamin-k-1 has been researched along with carboxyethyl-hydroxychroman* in 1 studies
Other Studies
1 other study(ies) available for vitamin-k-1 and carboxyethyl-hydroxychroman
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Vitamin E decreases extra-hepatic menaquinone-4 concentrations in rats fed menadione or phylloquinone.
The mechanism for increased bleeding and decreased vitamin K status accompanying vitamin E supplementation is unknown. We hypothesized that elevated hepatic α-tocopherol (α-T) concentrations may stimulate vitamin K metabolism and excretion. Furthermore, α-T may interfere with the side chain removal of phylloquinone (PK) to form menadione (MN) as an intermediate for synthesis of tissue-specific menaquinone-4 (MK-4).. In order to investigate these hypotheses, rats were fed phylloquinone (PK) or menadione (MN) containing diets (2 μmol/kg) for 2.5 weeks. From day 10, rats were given daily subcutaneous injections of either α-T (100 mg/kg) or vehicle and were sacrificed 24 h after the seventh injection. Irrespective of diet, α-T injections decreased MK-4 concentrations in brain, lung, kidney, and heart; and PK in lung. These decreases were not accompanied by increased excretion of urinary 5C- or 7C-aglycone vitamin K metabolites, however, the urinary α-T metabolite (α-CEHC) increased ≥ 100-fold. Moreover, α-T increases were accompanied by downregulation of hepatic cytochrome P450 expression and modified expression of tissue ATP-binding cassette transporters.. Thus, in rats, high tissue α-T depleted tissue MK-4 without significantly increasing urinary vitamin K metabolite excretion. Changes in tissue MK-4 and PK levels may be a result of altered regulation of transporters. Topics: Administration, Oral; alpha-Tocopherol; Animals; ATP-Binding Cassette Transporters; Biotransformation; Chromans; Cytochrome P-450 Enzyme System; Dietary Supplements; Gene Expression Regulation; Injections, Subcutaneous; Liver; Male; Propionates; Random Allocation; Rats; Rats, Sprague-Dawley; RNA, Messenger; Tissue Distribution; Vitamin E; Vitamin K 1; Vitamin K 2; Vitamin K 3 | 2012 |