IGF-1 LR3 10 mg

IGF-1 LR3 (Long Arg3 Insulin-Like Growth Factor-1) is an extended and modified analog of the naturally occurring IGF-1 peptide. It features a substitution at position 3 (Arginine replaces Glutamic acid) combined with an extended 13-amino acid N-terminal sequence, resulting in 83 amino acids total versus 70 in native IGF-1. These modifications dramatically reduce binding to IGF binding proteins (IGFBPs), resulting in enhanced stability and prolonged biological activity.

IGF-1 was first characterized in the 1950s as "sulfation factor" and later identified as a mediator of growth hormone's anabolic effects. The LR3 variant was engineered in the 1990s to overcome the short half-life limitation of native IGF-1, which is rapidly sequestered by IGFBPs in circulation. By reducing IGFBP binding affinity, LR3 maintains higher free concentrations and extended activity — making it the preferred form for in vitro and research applications.

Key Areas:

• Cell Proliferation — IGF-1 LR3 is one of the most potent mitogens for research. Its reduced IGFBP binding means more free peptide is available to activate the IGF-1 receptor, driving cell division across multiple cell types.
• Muscle Biology — Research demonstrates IGF-1 LR3 stimulates muscle protein synthesis through PI3K/Akt/mTOR signaling, promotes satellite cell activation, and inhibits muscle protein degradation.
• Metabolic Signaling — IGF-1 LR3 activates insulin receptor substrate (IRS) signaling, influencing glucose uptake, lipid metabolism, and overall metabolic regulation.
• Anti-Apoptosis — Studies show IGF-1 LR3 promotes cell survival by activating anti-apoptotic pathways (PI3K/Akt), making it valuable in cell survival, neuroprotection, and tissue preservation research.

These results come from peer-reviewed studies published in leading scientific journals. IGF-1 LR3's enhanced stability and reduced IGFBP binding make it the gold standard for IGF-1 receptor research and cell culture applications.