IGF-1 LR3 (Insulin-like Growth Factor-1 Long Arg3) from Super Human Peptides UK is a highly advanced, synthetic analogue of human IGF-1. It is an 83-amino acid sequence comprising the complete human IGF-1 sequence, but with an arginine substitution at position 3 and a 13-amino acid extension peptide at the N-terminus. In laboratory research, these specific modifications give IGF-1 LR3 a profound advantage over standard IGF-1.
The structural changes prevent the peptide from binding to Insulin-like Growth Factor-Binding Proteins (IGFBPs), which normally neutralize circulating IGF-1. By evading these binding proteins, IGF-1 LR3 achieves a dramatically extended biological half-life (extending from approximately 20 minutes to 20–30 hours) and exhibits exponentially higher potency. Produced under GMP-compliant conditions and verified for 99% purity or higher, IGF-1 LR3 is the premier model for investigating cellular hyperplasia, massive tissue regeneration, and metabolic nutrient partitioning.
- —Structural Extension: 83-amino acid sequence modified to evade IGF-binding proteins.
- —Extended Half-Life: Pharmacokinetics extended from minutes to over 20 hours for prolonged systemic receptor activation.
- —Cellular Hyperplasia: Studied for its unique ability to stimulate the division and formation of new cells (hyperplasia), rather than merely increasing the size of existing cells (hypertrophy).
- —High Purity: 99% purity or higher (verified by HPLC and MS analysis).
- —Quality Standard: GMP / ISO certified manufacturing.
- —IGFBP Evasion: Studying the precise mechanisms by which the N-terminal extension prevents neutralization by binding proteins in the bloodstream.
- —Cellular Hyperplasia: Measuring the proliferation and differentiation of satellite cells into fully mature muscle fibers.
- —Nutrient Partitioning: Researching the peptide's ability to inhibit cellular glucose uptake, forcing the body to utilize fatty acids for energy while shuttling amino acids directly into muscle tissue.
- —Systemic Repair: Preclinical models investigating the recovery of severe musculoskeletal trauma and burn injuries over prolonged periods.
- —Gut Health: Exploring the rapid regeneration of intestinal epithelial tissue in models of severe bowel disease or inflammation.
IGF-1 LR3 was engineered to overcome the primary limitation of natural IGF-1: its rapid neutralization in the bloodstream. Endogenous IGF-1 is heavily bound (over 95%) by IGFBPs, rendering it inactive. Laboratory studies by Tomas et al.
demonstrated that modifying the sequence with the "Long Arg3" addition resulted in an analogue that simply cannot be bound by these neutralizing proteins. As a result, in-vivo and in-vitro studies have shown that IGF-1 LR3 is approximately two to three times more potent than natural IGF-1. Animal models treated with IGF-1 LR3 display massive increases in nitrogen retention, rapid tissue repair, and profound muscle hyperplasia.
Because its extended half-life allows it to circulate systemically for an entire day, it has become the standard laboratory compound for researching the absolute limits of the IGF-1 receptor pathway and whole-body cellular regeneration.
- 1.Tomas, F.M. et al., "IGF-I variants which bind poorly to IGF-binding proteins show more potent diabetogenic and strongly enhanced somatogenic effects in diabetic rats," Journal of Endocrinology, 1995.
- 2.Francis, G.L. et al., "Novel cleavage of a variant insulin-like growth factor-I (IGF-I) yields a truncated peptide (des-1-3-IGF-I) with enhanced biological activity," Biochemical Journal, 1992.
- 3.Lord, A.P. et al., "The binding of IGF-I and IGF-I variants to human serum IGFBPs," Journal of Endocrinology, 2001.
- 4.Adams, G.R. et al., "Time course of changes in markers of myogenesis in overloaded rat skeletal muscle," Journal of Applied Physiology, 1999.
