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IGF-1 Binding Proteins

Meaning

IGF-1 Binding Proteins (IGFBPs) are a family of six distinct proteins that regulate the transport, half-life, and biological activity of Insulin-like Growth Factor-1 (IGF-1) within the circulation and target tissues. These proteins bind the majority of circulating IGF-1, acting as both a reservoir and a critical modulator of its bioavailability. Only the small fraction of IGF-1 not bound to IGFBPs is immediately available to bind to the IGF-1 receptor and exert its anabolic effects. The ratio and specific type of IGFBP present are therefore vital determinants of IGF-1’s overall biological impact on metabolism and growth.