title: Response of serum carboxylated and undercarboxylated osteocalcin to risedronate monotherapy and combined therapy with vitamin K(2) in corticosteroid-treated patients: a pilot study.
abstract: OBJECTIVE
  The aim of this study was to investigate the responses of serum osteocalcin (OC), undercarboxylated osteocalcin (ucOC) and N-terminal telopeptide of type I collagen (NTx) to corticosteroids, and to examine the effects of risedronate therapy with or without vitamin K(2) supplementation on bone metabolic markers in corticosteroid-treated patients.
  
  
  METHODS
  Sixteen patients on corticosteroid therapy for neuromuscular disorders were assigned randomly to 2 groups (A: risedronate monotherapy, n=8; B: combined risedronate and vitamin K(2) therapy, n=8) and treated for 1 year. Another 6 patients who received intravenous steroid pulse therapy were assigned to group C for investigation of the effects of corticosteroids on OC and ucOC 1 month after pulse therapy.
  
  
  RESULTS
  Serial measurements revealed that significant decreases of OC, ucOC and NTx persisted with a similar time course profile during 1 year of treatment in groups A and B, and between-group analysis failed to demonstrate any additional effects of vitamin K(2) on risedronate therapy. Intravenous steroid pulse therapy induced a transient depression of OC and ucOC within 1 week in group C.
  
  
  CONCLUSIONS
  These results indicate that serum concentrations of OC and ucOC become consistently low during corticosteroid administration despite risedronate therapy with or without vitamin K(2) supplementation, and the serum ucOC level may not be a reliable indicator of vitamin K status under corticosteroid administration.
authors.affiliation: Department of Neurology, Sapporo Medical University School of Medicine.
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Hozuki
authors.forename: Tomihiro
authors.initials: T
authors.lastname: Imai
authors.forename: Emiko
authors.initials: E
authors.lastname: Tsuda
authors.forename: Akihiro
authors.initials: A
authors.lastname: Matsumura
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamamoto
authors.forename: Takanobu
authors.initials: T
authors.lastname: Toyoshima
authors.forename: Syuuichiro
authors.initials: S
authors.lastname: Suzuki
authors.forename: Rika
authors.initials: R
authors.lastname: Yamauchi
authors.forename: Takashi
authors.initials: T
authors.lastname: Hayashi
authors.forename: Shin
authors.initials: S
authors.lastname: Hisahara
authors.forename: Shun
authors.initials: S
authors.lastname: Shimohama
mesh_terms: D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000187:drug effects; D050071:Bone Density Conservation Agents / Q000494:pharmacology / Q000627:therapeutic use*; D001842:Bone and Bones / Q000378:metabolism; D024042:Collagen Type I / Q000097:blood; D004305:Dose-Response Relationship, Drug; D004359:Drug Therapy, Combination; D012968:Etidronic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009468:Neuromuscular Diseases / Q000097:blood* / Q000188:drug therapy*; D015675:Osteocalcin / Q000097:blood*; D010455:Peptides / Q000097:blood; D010865:Pilot Projects; D011239:Prednisolone / Q000627:therapeutic use; D000068296:Risedronic Acid; D016896:Treatment Outcome; D024482:Vitamin K 2 / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D000305:Adrenal Cortex Hormones; D015415:Biomarkers; D050071:Bone Density Conservation Agents; D024042:Collagen Type I; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D024482:Vitamin K 2; D011239:Prednisolone; D000068296:Risedronic Acid; D012968:Etidronic Acid