The biological activity and tissue distribution of 2',3'-dihydrophylloquinone in rats.
2',3'-Dihydrophylloquinone (dihydro-K1) is a hydrogenated form of vitamin K1 (K1), which is produced during the hydrogenation of K1-rich plant oils. In this study, we found that dihydro-K1 counteracts the sodium warfarin-induced prolonged blood coagulation in rats. This indicates that dihydro-K1 functions as a cofactor in the posttranslational gamma-carboxylation of the vitamin K-dependent coagulation factors. It was also found that dihydro-K1 as well as K1 inhibits the decreasing effects of warfarin on the serum total osteocalcin level. In rats, dihydro-K1 is well absorbed and detected in the tissues of the brain, pancreas, kidney, testis, abdominal aorta, liver and femur. K1 is converted to menaquinone-4 (MK-4) in all the above-mentioned tissues, but dihydro-K1 is not. The unique characteristic of dihydro-K1 possessing vitamin K activity and not being converted to MK-4 would be useful in revealing the as yet undetermined physiological function of the conversion of K1 to MK-4.
Sato
Toshiro
T
Nutrition Research Laboratories, Honen Corporation, Asaba-cho, Iwata-gun, Shizuoka 437-1111, Japan. tsato@honen.co.jp
Ozaki
Rumi
R
Kamo
Shuichi
S
Hara
Yusuke
Y
Konishi
Satoru
S
Isobe
Yosuke
Y
Saitoh
Sanshiroh
S
Harada
Hiroshi
H
D000818:Animals; D008297:Male; D015675:Osteocalcin / Q000097:blood; D051381:Rats; D017207:Rats, Sprague-Dawley; D014018:Tissue Distribution; D010837:Vitamin K 1 / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics / Q000494:pharmacology*
C121368:dihydrophylloquinone; D015675:Osteocalcin; C028843:vitamin K1 hydroquinone; D010837:Vitamin K 1