Excess α-tocopherol decreases extrahepatic phylloquinone in phylloquinone-fed rats but not menaquinone-4 in menaquinone-4-fed rats
Article first published online: 16 APR 2014
© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Molecular Nutrition & Food Research
Special Issue: Vitamin K Conundrums
Volume 58, Issue 8, pages 1601–1609, August 2014
How to Cite
Hanzawa, F., Sakuma, E., Nomura, S., Uchida, T., Oda, H. and Ikeda, S. (2014), Excess α-tocopherol decreases extrahepatic phylloquinone in phylloquinone-fed rats but not menaquinone-4 in menaquinone-4-fed rats. Mol. Nutr. Food Res., 58: 1601–1609. doi: 10.1002/mnfr.201300710
- Issue published online: 4 AUG 2014
- Article first published online: 16 APR 2014
- Manuscript Accepted: 5 MAR 2014
- Manuscript Revised: 4 MAR 2014
- Manuscript Received: 26 SEP 2013
- Vitamin E;
- Vitamin K
The effects of vitamin E on vitamin K metabolism were elucidated by comparing the effect of tocopherol intake on vitamin K concentrations in rats fed phylloquinone (PK) or menaquinone (MK)-4.
Methods and results
Initially, the dietary effect of RRR-α-tocopherol, but not RRR-γ-tocopherol, in decreasing extrahepatic PK concentrations was confirmed. Subsequently, rats were fed a PK or MK-4-containing diet (0.75 mg/kg) with RRR-α-tocopherol (0, 10, 50, or 500 mg/kg) for 6 weeks. In rats fed PK, α-tocopherol consumption decreased PK in kidney, lung, heart, muscle, testis, and brain but not in serum and liver. However, in rats fed MK-4, α-tocopherol consumption did not decrease MK-4 in serum and tissues. Finally, vitamin K- and E-depleted rats were administered PK or MK-4 (0.2 mg) with RRR-α-tocopherol (0, 1, or 10 mg) by gavage. After PK administration, α-tocopherol was observed to decrease PK in kidney, adrenal gland, lung, testis, and brain but not in serum and liver, whereas, after MK-4 administration, α-tocopherol did not affect MK-4 in serum and tissues.
Excess α-tocopherol decreased extrahepatic PK in rats fed PK but not MK-4 in rats fed MK-4.