Pharmacokinetics of α-tocopherol stereoisomers in plasma and milk of cows following a single dose injection of all-rac-α-tocopheryl acetate. (25th April 2020)

• Record Type: Journal Article
• Authors: Jensen, S.K.; Lashkari, S.; Kristensen, N.B.
• Is Part Of: Food chemistry. Volume 310(2020)
• Publication Date: 2020-04-25
• Subjects: Bioavailability -- Biodiscrimination -- Vitamin E -- Half-life -- Elimination rate -- Cows; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2019.125931
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: Highest half-life and lowest elimination rate was observed in RRR-α-tocopherol. Mammary gland of cows discriminates toward RRR-α-tocopherol. The majority of the Ʃ2S stereoisomers was found in the liver. 2R-α-tocopherol stereoisomers were more equal distributed between liver and plasma. Abstract: Among different stereoisomers of all-rac -α-tocopherol, 2R-stereoisomers have higher biological activities than their 2S-stereoisomers. Two experiments were conducted to study the pharmacokinetics of stereoisomers of all-rac -α-tocopherol and investigated the discrimination and distribution of α-tocopherol stereoisomers in plasma and milk as well as quantitative secretion into milk with lactating Holstein cows after a single dose intramuscular injection of 2.50 g of all-rac -α-tocopheryl acetate. The highest half-life (2.92/h) and lowest elimination rate (0.36/h) were found for RRR-α-tocopherol. After a single dose injection of all-rac -α-tocopherol, highest maximal daily increase (Smax, 8.36 mg/day) and accumulation secretion (AS, 50.8 mg) were observed for milk RRR-α-tocopherol. The majority of the Ʃ2S stereoisomers were found in the liver 36 h post injection, while the 2R stereoisomers were more equal distributed between liver and plasma. The present findings showed a clear discrimination between RRR-α-tocopherol, synthetic 2R stereoisomers and Ʃ2S stereoisomers in milk and plasma of dairy cows.