IGF-1 LR3

Overview

IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is an 83-amino acid analog of IGF-1 with an arginine substitution at position 3 and a 13-amino acid N-terminal extension. These modifications dramatically reduce binding to IGF-binding proteins (IGFBPs), resulting in a significantly longer half-life and greater bioavailability compared to native IGF-1.

Mechanism of Action

IGF-1 LR3 activates the IGF-1 receptor (IGF-1R), triggering the PI3K/Akt and Ras/MAPK signaling cascades. These promote protein synthesis, cell proliferation, cell survival (anti-apoptosis), and glucose uptake. Because it is not sequestered by IGFBPs, a larger fraction remains active in circulation, producing more potent effects per unit than native IGF-1.

Research Context

IGF-1 LR3 is primarily studied for its anabolic effects on skeletal muscle, its role in tissue growth and repair, and its interactions with the GH/IGF-1 axis. The high price reflects the complexity of producing a correctly folded 83-amino acid protein.

Key Research Areas

Considerations for Researchers

Premium pricing. Store at -20C. Requires careful handling due to protein size. Verify correct folding and biological activity. Do not confuse with native IGF-1 or IGF-1 DES, which have different pharmacokinetic profiles.