Aging Impairs IGF‐I Receptor Activation and Induces Skeletal Resistance to IGF‐I

IGF‐I plays an important anabolic role in stimulating bone formation and maintaining bone mass. We show that the pro‐proliferative, anti‐apoptotic, and functional responses to IGF‐I in bone and BMSCs decrease with aging. These changes are associated with impaired receptor activation and signal transduction through the MAPK and PI3K pathways.

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