Two months of daily oral MK-677 increased markers of both bone formation and bone breakdown in obese young males, with bone formation markers rising more — suggesting net positive bone effects.
Formation > resorptionBone formation markers rose more than resorption markers during 8 weeks of MK-677, suggesting net bone-building activity
What the researchers found
MK-677 (25 mg/day for 8 weeks) increased bone formation markers more than resorption markers in 24 obese young males, with elevated IGF-1 levels suggesting a growth hormone-mediated anabolic bone effect.
Why it matters
Bone loss is a major health concern in aging and obesity. An oral medication that increases bone formation could potentially prevent osteoporosis, and this study shows MK-677 activates bone-building processes.
How the study worked
Randomized, double-blind, placebo-controlled parallel study. 24 obese males (BMI >30, ages 19-49) received MK-677 25 mg/day or placebo for 8 weeks. Bone turnover markers, GH, and IGF-1 were measured.
What this study cannot tell us
Short duration (8 weeks) — bone density changes take months to years to manifest. Markers indicate bone turnover direction but don't directly measure bone density. Obese young male population may not represent the groups most at risk for osteoporosis.
How to read the evidence
Moderate evidence from a well-designed RCT with appropriate controls, but limited by short duration, small sample, and use of surrogate markers rather than direct bone density measurement.
When this study was published
Published in 1998. MK-677's bone effects have been studied further in aging populations with longer follow-up periods.
The bigger picture
Growth hormone is known to support bone density, but GH injections are impractical for widespread use. An oral GH secretagogue that stimulates bone formation could become a practical alternative for preventing osteoporosis in various populations.
Questions still open
- Does the net positive bone marker balance translate to actual bone density improvements over time?
- Would MK-677 benefit postmenopausal women or elderly men with osteoporosis?
- What is the optimal treatment duration for bone effects?
Common questions
Can MK-677 strengthen bones?
Why study bone effects in obese young men?
Read the original research
Treatment with the oral growth hormone secretagogue MK-677 increases markers of bone formation and bone resorption in obese young males.
Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research, 13(7), 1158-66
Citation
Svensson, J; Ohlsson, C; Jansson, J O; Murphy, G; Wyss, D; Krupa, D; Cerchio, K; Polvino, W; Gertz, B; Baylink, D; Mohan, S; Bengtsson, B A. (1998). Treatment with the oral growth hormone secretagogue MK-677 increases markers of bone formation and bone resorption in obese young males.. Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research, 13(7), 1158-66.