title: Association of serum undercarboxylated osteocalcin with serum estradiol in pre-, peri- and early post-menopausal women.
abstract: OBJECTIVE
  We investigated changes in serum concentration of undercarboxylated osteocalcin (ucOC), which is a sensitive marker of vitamin K status, and association of ucOC concentration with estradiol concentration in pre-, peri- and early post-menopausal women.
  
  
  METHODS
  The study population consisted of 193 pre-, peri- and post-menopausal Japanese women aged 39-66 yr. Serum ucOC concentration was measured to assess vitamin K status; serum concentrations of intact osteocalcin (OC) and bone-specific alkaline phosphatase (BAP) were measured as bone formation markers; and urine concentration of N-telopeptide was measured as a bone resorption marker. Serum estradiol and estrone concentrations were measured by a highly sensitive radioimmunoassay. Bone mineral density (BMD) was measured at the lumbar spine.
  
  
  RESULTS
  Serum concentration of ucOC in peri-menopausal women was significantly (p=0.0005) higher than that in pre-menopausal women, while serum OC concentration in post-menopausal women for whom 1 yr had passed since menopause was significantly (p=0.0003, p=0.024, respectively) higher than the concentrations in pre-menopausal and peri-menopausal women. Serum ucOC concentration showed a significant negative correlation with estradiol concentration (r=-0.372, p<0.0001) and a significant positive correlation with serum FSH concentration (r=0.324, p<0.0001). Serum OC concentration was positively correlated with serum FSH concentration (r=0.317, p<0.001).
  
  
  CONCLUSIONS
  The results showed that the change in ucOC concentration during the menopausal transition is different from that in OC concentration. In addition, serum ucOC concentration is closely associated not only with FSH concentration but also estradiol concentration.
authors.affiliation: Department of Obstetrics and Gynecology, School of Medicine, University of Tokushima, Tokushima 770-8503, Japan. yasui@clin.med.tokushima-u.ac.jp
authors.forename: T
authors.initials: T
authors.lastname: Yasui
authors.forename: H
authors.initials: H
authors.lastname: Uemura
authors.forename: J
authors.initials: J
authors.lastname: Tomita
authors.forename: Y
authors.initials: Y
authors.lastname: Miyatani
authors.forename: M
authors.initials: M
authors.lastname: Yamada
authors.forename: M
authors.initials: M
authors.lastname: Miura
authors.forename: M
authors.initials: M
authors.lastname: Irahara
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000097:blood; D000469:Alkaline Phosphatase / Q000097:blood; D015519:Bone Density / Q000502:physiology; D024042:Collagen Type I / Q000652:urine; D003430:Cross-Sectional Studies; D004958:Estradiol / Q000097:blood*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D008159:Lumbar Vertebrae / Q000502:physiology; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood*; D010455:Peptides / Q000652:urine; D047648:Perimenopause / Q000097:blood* / Q000502:physiology; D017698:Postmenopause / Q000097:blood* / Q000502:physiology; D017697:Premenopause / Q000097:blood* / Q000502:physiology; D014812:Vitamin K / Q000097:blood
chemical_list: D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D014812:Vitamin K; D004958:Estradiol; D005640:Follicle Stimulating Hormone; D000469:Alkaline Phosphatase