title: Low-dose vitamin K2 (MK-4) supplementation for 12 months improves bone metabolism and prevents forearm bone loss in postmenopausal Japanese women.
abstract: Menaquinone-4 (MK-4) administered at a pharmacological dosage of 45 mg/day has been used for the treatment of osteoporosis in Japan. However, it is not known whether a lower dose of MK-4 supplementation is beneficial for bone health in healthy postmenopausal women. The aim of this study was to examine the long-term effects of 1.5-mg daily supplementation of MK-4 on the various markers of bone turnover and bone mineral density (BMD). The study was performed as a randomized, double-blind, placebo-controlled trial. The participants (aged 50-65 years) were randomly assigned to one of two groups according to the MK-4 dose received: the placebo-control group (n = 24) and the 1.5-mg MK-4 group (n = 24). The baseline concentrations of undercarboxylated osteocalcin (ucOC) were high in both groups (>5.1 ng/ml). After 6 and 12 months, the serum ucOC concentrations were significantly lower in the MK-4 group than in the control group. In the control group, there was no significant change in serum pentosidine concentrations. However, in the MK-4 group, the concentration of pentosidine at 6 and 12 months was significantly lower than that at baseline. The forearm BMD was significantly lower after 12 months than at 6 months in the control group. However, there was no significant decrease in BMD in the MK-4 group during the study period. These results suggest that low-dose MK-4 supplementation for 6-12 months improved bone quality in the postmenopausal Japanese women by decreasing the serum ucOC and pentosidine concentrations, without any substantial adverse effects.
authors.affiliation: Department of Food Function and Labeling, National Institute of Health and Nutrition, 1-23-1 Toyama, Shinjyuku-ku, Tokyo, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Koitaya
authors.forename: Mariko
authors.initials: M
authors.lastname: Sekiguchi
authors.forename: Yuko
authors.initials: Y
authors.lastname: Tousen
authors.forename: Yoriko
authors.initials: Y
authors.lastname: Nishide
authors.forename: Akemi
authors.initials: A
authors.lastname: Morita
authors.forename: Jun
authors.initials: J
authors.lastname: Yamauchi
authors.forename: Yuko
authors.initials: Y
authors.lastname: Gando
authors.forename: Motohiko
authors.initials: M
authors.lastname: Miyachi
authors.forename: Mami
authors.initials: M
authors.lastname: Aoki
authors.forename: Miho
authors.initials: M
authors.lastname: Komatsu
authors.forename: Fumiko
authors.initials: F
authors.lastname: Watanabe
authors.forename: Koji
authors.initials: K
authors.lastname: Morishita
authors.forename: Yoshiko
authors.initials: Y
authors.lastname: Ishimi
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D015519:Bone Density; D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005542:Forearm; D006801:Humans; D007564:Japan; D008875:Middle Aged; D015663:Osteoporosis, Postmenopausal / Q000517:prevention & control*; D017698:Postmenopause; D011795:Surveys and Questionnaires; D013997:Time Factors; D024482:Vitamin K 2 / Q000097:blood / Q000378:metabolism* / Q000652:urine
chemical_list: D015415:Biomarkers; D024482:Vitamin K 2