Autocrine and Paracrine Actions of IGF-I Signaling in Skeletal Development

摘要: Insulin-like growth factor-I (IGF-I) regulates cell growth, survival, and differentiation by acting on the IGF-I receptor, (IGF-IR)-a tyrosine kinase which elicits diverse intracellular signaling responses. All skeletal cells express IGF-IR. Recent studies using tissue/cell-specific gene knockout mouse models culture techniques have clearly demonstrated that locally produced is more critical than systemic in supporting embryonic postnatal development bone remodeling. Local IGF-I/IGF-IR promotes survival of chondrocytes osteoblasts, directly indirectly, altering other autocrine/paracrine pathways cartilage bone, enhancing interactions among these through hormonal physical means. Moreover, local for anabolic actions hormone parathyroid hormone. Herein, we review evidence above aspects