IGF-DES (1-3)
Naturally occurring truncated IGF-1 variant lacking the first three amino acids; high receptor potency with a very short half-life.
Overview
IGF-DES, also written des(1-3) IGF-1, is a truncated form of insulin-like growth factor 1 missing the three N-terminal amino acids found in the native molecule. This variant occurs naturally through alternative processing and is notable for binding IGF-binding proteins far more weakly than full-length IGF-1. Because of that property it shows high potency at the IGF-1 receptor in vitro, at the cost of a very short circulating half-life, which shapes how it is used in research.
Mechanism
Removal of the first three residues does not impair IGF-1 receptor activation but removes a major binding-protein contact site. Unbound IGF-DES therefore reaches the receptor rapidly and potently drives the anabolic PI3K-Akt and MAPK signaling cascades. Its brief persistence favors localized, short-acting effects and makes it a common tool for studying acute IGF-1 signaling.
Dosing
In research protocols IGF-DES is typically injected locally or subcutaneously, often multiple times daily in animal studies because of its short half-life; dosing is protocol-specific and should be taken from the primary literature. It is also used in cell-culture research at concentrations reported per study.
Expected Effects
- rapid activation of IGF-1 receptor signaling in target tissues
- local anabolic effects in muscle-injection research models
- higher receptor potency than native IGF-1 in binding-protein-containing systems
Side Effects & Tolerability
No systematic human safety data exist for IGF-DES. As with other IGF-1 receptor agonists, theoretical concerns include hypoglycemia and mitogenic signaling; these have not been characterized for this variant in humans.
Storage
Lyophilized IGF-DES should be stored desiccated, protected from light, and kept frozen at -20 deg C or below. After reconstitution, refrigerate at 2-8 deg C and use promptly, avoiding repeated freeze-thaw cycles.