Reducing Undercarboxylated Osteocalcin With Vitamin K Supplementation Does Not Promote Lean Tissue Loss or Fat Gain Over 3 Years in Older Women and Men: A Randomized Controlled Trial.
Osteocalcin (OC) is a vitamin K-dependent protein synthesized during bone formation. Mice injected with the undercarboxylated form of OC (ucOC) had more skeletal muscle mass and less fat mass than sham-treated controls, suggesting a unique metabolic role for ucOC. UcOC decreases in response to vitamin K supplementation. Our objective was to determine the effect of reducing ucOC on change in lean tissue and fat mass in older community-dwelling adults (n = 401, mean ± SD 69 ± 6 years) using data from a randomized controlled trial of vitamin K supplementation. Over 3 years, serum ucOC was reduced by 58% in women and by 61% in men randomized to vitamin K, whereas in the control group, ucOC decreased by 1% in women and 4% in men (supplementation*time p < 0.001 in men and women). However, there were no differences in the change in appendicular lean mass (calculated as arm lean mass + leg lean mass) or total body fat mass between women randomized to vitamin K and control over 3 years (supplementation*time p values all ≥ 0.18) or between men randomized to vitamin K and control (supplementation*time p values all ≥ 0.54). Consistent with these findings, ucOC was not associated cross-sectionally with appendicular lean mass or fat mass in men or women after adjustment for total OC at baseline (all p ≥ 0.12). These findings indicate the undercarboxylated form of OC is not implicated in age-related changes in skeletal muscle or adipose tissue mass in older community-dwelling adults. © 2016 American Society for Bone and Mineral Research.
USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA.
M Kyla
MK
Shea
USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA.
Bess
B
Dawson-Hughes
Yale University School of Medicine, New Haven, CT, USA.
Caren M
CM
Gundberg
USDA Human Nutrition Research Center on Aging, Tufts University, Boston, MA, USA.
Sarah L
SL
Booth
D050154:Adiposity / Q000187:drug effects; D000368:Aged; D000369:Aged, 80 and over; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood*; D013851:Thinness / Q000097:blood*; D014812:Vitamin K / Q000494:pharmacology*
D015675:Osteocalcin; D014812:Vitamin K