Carboxylation of osteocalcin in post-menopausal osteoporotic women following vitamin K and D supplementation.
The effect of vitamin supplements on bone metabolism indices in patients with osteoporosis has received scant attention in the literature. Over a 2-week period, vitamin supplements of K and K+D were given to 20 post-menopausal osteoporotic women with previous Colles fractures. Osteoporosis was confirmed by bone mass measurements that demonstrated that broadband ultrasound attenuation (os calcis) was almost as discriminatory as dual energy X-ray absorptiometry (spine and hip) in Colles fracture patients compared with matched controls. Vitamin K corrected the carboxylation defect in osteocalcin and while less marked 4 weeks later, the improvement was still detectable. The result after K+D was similar. The level of carboxylation became the same as in premenopausal women. Total osteocalcin level (bound) osteocalcin. While there was vitamin K correctable undercarboxylation of osteocalcin, simultaneously there was no evidence of undercarboxylation of prothrombin.
Douglas
A S
AS
University Department of Medicine & Therapeutics, Medical School, Aberdeen, UK.
Robins
S P
SP
Hutchison
J D
JD
Porter
R W
RW
Stewart
A
A
Reid
D M
DM
D015502:Absorptiometry, Photon; D000328:Adult; D000368:Aged; D015415:Biomarkers; D015519:Bone Density / Q000187:drug effects; D003100:Colles' Fracture / Q000000981:diagnostic imaging / Q000503:physiopathology; D018592:Cross-Over Studies; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood / Q000737:chemistry / Q000378:metabolism*; D015663:Osteoporosis, Postmenopausal / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000378:metabolism; D017697:Premenopause / Q000097:blood; D011498:Protein Precursors / Q000378:metabolism; D011516:Prothrombin / Q000737:chemistry / Q000378:metabolism; D012372:ROC Curve; D016037:Single-Blind Method; D013115:Spinal Canal / Q000000981:diagnostic imaging / Q000502:physiology; D014463:Ultrasonography; D014807:Vitamin D / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D014812:Vitamin K / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*
D015415:Biomarkers; D011498:Protein Precursors; D015675:Osteocalcin; D014812:Vitamin K; D014807:Vitamin D; C008208:acarboxyprothrombin; D011516:Prothrombin