What is the Origin of Insulin Growth Factor 1?

IGF-1 was initially identified and named due to its demonstrable insulin-like metabolic properties and its critical role in mediating the systemic effects of growth hormone. Its discovery formally established the somatotropic axis, defining the liver as a central endocrine organ in this cascade. This hormone is a fundamental biomarker in endocrinology, particularly in the assessment of pediatric growth disorders and age-related physiological decline.

What is the Mechanism of Insulin Growth Factor 1?

IGF-1 circulates predominantly bound to a family of specific binding proteins, which meticulously regulate its half-life and local tissue bioavailability. It exerts its powerful effects by binding to the IGF-1 receptor, a transmembrane tyrosine kinase, which initiates a complex and vital intracellular signaling cascade, primarily the PI3K/Akt pathway. This pathway is a master regulator of cell survival, anti-apoptosis, and protein synthesis, thereby driving systemic tissue anabolism and regeneration.

Insulin Growth Factor 1

Meaning

Insulin Growth Factor 1 (IGF-1) is a potent, single-chain polypeptide hormone primarily synthesized and secreted by the liver in direct response to stimulation by circulating Growth Hormone (GH). IGF-1 functions as the principal endocrine mediator of GH’s widespread anabolic and growth-promoting effects throughout the entire body. This critical hormone is essential for cellular proliferation, differentiation, and tissue repair, exerting significant influence on muscle protein synthesis, bone mineral density, and neurocognitive function. Clinical measurement of IGF-1 serves as the most reliable indicator of average GH secretion.