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A naturally occurring and synthetically produced truncated form of IGF-1 lacking the first three N-terminal amino acids (Gly-Pro-Glu), a deletion that sharply reduces IGF binding protein affinity and is studied as a highly potent IGF-1R agonist in vitro.
IGF-1 DES, more precisely DES(1-3)IGF-1, is a truncated variant of insulin-like growth factor 1 that lacks the first three amino acids (glycine-proline-glutamate) at the N-terminus. This form occurs naturally in some tissues and is also produced synthetically for research. The missing tripeptide is the region responsible for a substantial portion of IGF-1's interaction with its binding proteins.
Removal of these residues greatly reduces the molecule's affinity for IGFBPs, which in laboratory studies increases the fraction free to engage the IGF-1 receptor. As a result, DES(1-3)IGF-1 is frequently reported in the literature as more potent than intact IGF-1 in cell-based assays.
It is handled exclusively as a research reagent for in vitro and preclinical study of insulin-like growth factor signaling.
Like intact IGF-1, DES(1-3)IGF-1 signals through the IGF-1 receptor tyrosine kinase, activating PI3K/Akt and Ras/MAPK cascades associated with proliferation and survival signaling in experimental cell systems.
Its defining property is markedly reduced IGFBP binding due to the absent N-terminal tripeptide. Because IGFBPs normally sequester IGF-1 and limit receptor access, the truncated analog shows enhanced apparent potency in cultures containing binding proteins, making it a useful tool for dissecting IGFBP-dependent versus receptor-dependent effects.
The following describe published experimental studies for reporting purposes only; they are not usage directions.
Ballard, Francis and colleagues characterized DES(1-3)IGF-1 as several-fold more potent than intact IGF-1 in stimulating cell growth in cultures containing IGF binding proteins, attributing the difference to reduced IGFBP sequestration (Ballard et al., 1987–1991 series).
Preclinical neuroscience studies have reported DES(1-3)IGF-1 as a neurotrophic factor in animal models of neuronal injury, where investigators administered the peptide and measured markers of neuronal survival; these are cited as research findings only.
Combinations examined in the research literature. Descriptive only — not a recommendation to combine compounds.
References are being compiled for this entry.