MK-677 Boosts Bone Turnover in Older Adults, Suggesting Bone Health Benefits

Growth hormone (GH) levels naturally decline with age, a phenomenon known as somatopause, which contributes to age-related bone loss and increases the risk of osteoporosis. GH secretagogues, such as MK-677, are compounds designed to stimulate the body's own GH release, but their specific impact on bone metabolism in older populations was not fully understood. This study aimed to investigate whether oral administration of MK-677 could effectively increase markers of bone turnover in both healthy and functionally impaired elderly adults.

MK-677 treatment significantly increased markers of both bone formation and resorption. Serum osteocalcin levels, a key marker of bone formation, showed a sustained increase of 20-30% in the MK-677 group compared to placebo (p<0.01). Concurrently, urinary N-telopeptide levels, a marker of bone resorption, increased by 15-25% in the MK-677 group compared to placebo (p<0.01). The most significant finding was a sustained increase in both bone formation and resorption markers, indicating enhanced bone remodeling activity in the MK-677 group over the 12-month treatment period. These changes were observed consistently across both healthy and functionally impaired elderly subgroups, suggesting a broad effect on bone metabolism, with no significant differences in the magnitude of response between these groups.