Undercarboxylated osteocalcin concentration in postmenopausal women receiving hormone therapy daily and on alternate days.
OBJECTIVE
Undercarboxylated osteocalcin (ucOC) is a sensitive marker of vitamin K status. The authors examined the difference in serum ucOC concentrations in postmenopausal women receiving hormone therapy (HT) daily and on alternate days, and assessed the association between ucOC and triglyceride concentrations, which are related to the transport of vitamin K.


METHODS
Seventy-three postmenopausal women were recruited for this study. Thirty-seven women received 0.625 mg of conjugated equine estrogens (CEE) and 2.5 mg of medroxyprogesterone acetate (MPA) daily, and 36 women received 0.625 mg of CEE and 2.5 mg of MPA on alternate days. The concentrations of serum ucOC, bone turnover markers, lipid profiles, and hormones were measured before and after 12 months of HT.


RESULTS
The ucOC concentration in women taking HT daily was significantly (P < 0.01) lower than that in women taking HT on alternate days. Serum ucOC concentrations during HT showed a significant (P < 0.01) inverse correlation with estradiol concentrations during HT. Serum estradiol concentrations during HT showed a significant (P < 0.01) positive correlation with triglyceride concentrations during HT. Furthermore, ucOC concentrations during HT showed a significant (P < 0.05) inverse correlation with triglyceride concentrations in women receiving HT.


CONCLUSIONS
The effect of HT on alternate days on ucOC concentration was weaker than the effect of HT daily. In addition, ucOC concentration after 12 months of HT daily might be decreased due to the conversion of ucOC to carboxylated OC by the effect of vitamin K through increased triglyceride levels induced by oral CEE.
Yasui
Toshiyuki
T
Department of Obstetrics and Gynecology, School of Medicine, University of Tokushima, Tokushima, Japan. yashi@clin.med.tokushima-u.ac.jp
Uemura
Hirokazu
H
Umino
Yuka
Y
Yamada
Masayo
M
Kuwahara
Akira
A
Matsuzaki
Toshiya
T
Maegawa
Masahiko
M
Furumoto
Hiroyuki
H
Miura
Masakazu
M
Irahara
Minoru
M
D015415:Biomarkers / Q000097:blood; D016723:Bone Remodeling / Q000187:drug effects; D002245:Carbon Dioxide / Q000378:metabolism*; D004334:Drug Administration Schedule; D004958:Estradiol / Q000097:blood; D015914:Estrogen Replacement Therapy / Q000379:methods*; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage*; D004970:Estrone / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008055:Lipids / Q000097:blood; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage*; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood* / Q000378:metabolism; D017698:Postmenopause / Q000097:blood*; D014280:Triglycerides / Q000097:blood*; D014812:Vitamin K / Q000378:metabolism*
D015415:Biomarkers; D004966:Estrogens, Conjugated (USP); D008055:Lipids; D014280:Triglycerides; D015675:Osteocalcin; D014812:Vitamin K; D002245:Carbon Dioxide; C041069:carboxyl radical; D004970:Estrone; D004958:Estradiol; D017258:Medroxyprogesterone Acetate