IGF-1 LR3

IGF-1 LR3 (Insulin-like Growth Factor 1 Long Arg3) is an 83 amino acid synthetic analogue of human IGF-1 incorporating a 13 amino acid N-terminal extension and a Glu3 to Arg3 substitution. These two modifications reduce the affinity of IGF-1 LR3 for all six IGF binding proteins (IGFBPs) by approximately 1000-fold compared to native IGF-1, extending the free peptide half-life from 10-20 minutes to approximately 20-30 hours. This allows study of IGF-1R signalling independently of IGFBP regulation and tissue distribution effects.

Molecular formula: C400H625N111O115S9 | Molecular weight: 9117.5 g/mol | CAS: 946870-92-4 | Amino acids: 83 | Modifications: +13aa N-terminal extension, Glu3 to Arg3 | Purity: greater than or equal to 98% as verified by HPLC | Form: Lyophilised powder | Appearance: White to off-white lyophilised powder | Storage: -20°C desiccated

IGF-1 LR3 activates IGF-1R — a receptor tyrosine kinase in the insulin receptor family — triggering autophosphorylation and activation of two major downstream pathways. The PI3K/Akt/mTOR pathway promotes protein synthesis via S6K1 and 4E-BP1, cell survival via BAD phosphorylation, and glucose uptake via GLUT4 translocation. The Ras/MAPK/ERK pathway drives cell proliferation through immediate early gene transcription. Both pathways are studied in muscle cell biology, cancer research, and metabolic signalling.

Reconstitution requires bacteriostatic water containing 0.1% acetic acid to improve solubility; neutral aqueous conditions promote aggregation. IGF-1 LR3 research complements ACE-031 studies (opposing anabolic versus catabolic muscle signalling) and Tesamorelin research (GH axis stimulation upstream of IGF-1 production).

For laboratory and analytical research purposes only. Not for human or veterinary use.