Overview
IGF-1 DES, formally des(1-3)IGF-1, is a naturally occurring truncated variant of insulin-like growth factor-1 in which the first three amino acids (Gly-Pro-Glu) of the N-terminus have been removed. The truncated peptide was first isolated from bovine colostrum and human brain tissue and is now produced synthetically for research applications.
The N-terminal tripeptide is the principal binding site for the six insulin-like growth factor binding proteins (IGFBP-1 through -6) that normally sequester IGF-1 in circulation. By removing this domain, IGF-1 DES retains nearly full affinity for the IGF-1 receptor (IGF-1R) while binding IGFBPs roughly 10–20-fold more weakly. The free, unbound peptide is therefore more bioavailable at target tissues and is estimated to be 5–10× more potent than full-length IGF-1 on a molar basis in vitro.
Within muscle, IGF-1R activation by IGF-1 DES recruits the PI3K–Akt–mTOR pathway to drive protein synthesis and satellite-cell activation, and engages the MAPK cascade to promote myoblast proliferation. Because of its short circulating half-life and high local potency, IGF-1 DES is used almost exclusively as a localized site-injection peptide in research models, in contrast to the long-acting analog IGF-1 LR3.
There are no published controlled human trials of IGF-1 DES. It is not approved by any regulatory agency and is sold strictly as a research chemical. All discussion of dosing or effects derives from animal data and uncontrolled user reports.
Quick facts
- Mechanism
- IGF-1 receptor agonist with reduced IGFBP binding and enhanced local potency
- Primary use
- Localized hypertrophy and tissue-repair research
- Evidence
- limited
- FDA
- Not approved
- Route
- Subcutaneous or intramuscular injection (research only)
- Typical results
- Localized hypertrophic and repair effects in preclinical models within 2–4 weeks; no controlled human trials
Chemical information
IGF-1 DES (C₃₁₉H₄₉₅N₉₁O₉₆S₇) is a anabolic compound with a molecular weight of 7371.48 g/mol. Its structural characteristics underpin its biological activity in anabolic processes and muscle development.
How IGF-1 DES works
IGF-1 DES binds IGF-1R, a transmembrane tyrosine kinase whose autophosphorylation recruits insulin receptor substrate (IRS) proteins. Downstream signaling proceeds through the PI3K–Akt–mTOR axis, stimulating protein synthesis and inhibiting FoxO-mediated atrophy, and through the Ras–Raf–MEK–ERK pathway, driving proliferation and differentiation of myoblasts and other progenitor populations.
By lacking the IGFBP-binding tripeptide, IGF-1 DES is not sequestered in the IGFBP/ALS ternary complex that immobilizes most circulating IGF-1. The free peptide diffuses readily through interstitial tissue and engages IGF-1R rapidly. Combined with its short plasma half-life, this makes locally injected IGF-1 DES particularly suited to producing site-specific effects with relatively little systemic exposure.
In skeletal muscle, IGF-1 DES augments mechanical-overload-induced hypertrophy by amplifying satellite-cell proliferation and fusion. Animal studies show increased fiber cross-sectional area, elevated myonuclear number, and faster recovery from injury when IGF-1 DES is delivered locally to working muscle.
Beyond muscle, IGF-1R is widely expressed and IGF-1 DES has been studied in neural tissue (promoting neurite outgrowth), cartilage (supporting chondrocyte proliferation), and intestinal epithelium (driving mucosal repair). The same potency advantage that makes it attractive in research raises corresponding concerns about uncontrolled mitogenic and pro-tumorigenic signaling with sustained or systemic use.
- IGF-1R activation: Tyrosine-kinase receptor signaling through PI3K-Akt-mTOR and MAPK
- Reduced IGFBP binding: 10–20× lower affinity for binding proteins increases free fraction
- Enhanced potency: 5–10× more potent than full-length IGF-1 on molar basis in vitro
- Satellite-cell activation: Recruits and fuses muscle progenitor cells driving hypertrophy
- Short half-life: Favors localized site-injection rather than systemic exposure
Pharmacokinetics
| Parameter | Value | Significance |
|---|---|---|
| Molecular Mass | 7,371.48 g/mol | Three-residue truncation of native IGF-1 |
| Plasma half-life | ~20–30 minutes | Rapid clearance limits systemic exposure |
| IGFBP affinity | ~10–20× lower than IGF-1 | Higher unbound fraction at target tissues |
| Relative potency vs IGF-1 | ~5–10× (in vitro) | Lower doses produce equivalent receptor activation |
| Administration | Localized SC/IM injection | Designed for site-specific delivery, not systemic dosing |
Dosing & administration
IGF-1 DES dosing varies by indication and individual factors. No FDA-approved dosing exists for this compound; protocols in the literature derive from limited clinical or preclinical data and practitioner experience.
Any use should be conducted under qualified medical supervision with appropriate monitoring of safety markers.
Important: These dosing ranges are not FDA-approved. Any use should be under qualified medical supervision.
Side effects & safety
Safety data for IGF-1 DES is primarily derived from preclinical studies and limited human data. Long-term effects in humans remain incompletely characterized.
Common
- • Localized swelling and erythema at injection site
- • Transient hypoglycemia, especially with higher doses or fasting
- • Mild muscle ache or 'pump' at injected sites
- • Headache and lightheadedness
Serious / potential risks
- • Symptomatic hypoglycemia requiring carbohydrate intake
- • Potential acceleration of pre-existing or undiagnosed malignancy via IGF-1R signaling
- • Cardiac hypertrophy with chronic systemic use (extrapolated from acromegaly data)
- • Joint and soft-tissue overgrowth with prolonged use
- • Unknown long-term safety; no controlled human trials
Drug interactions
| Medication | Interaction | Recommendation |
|---|---|---|
| Exogenous insulin | Additive hypoglycemia via cross-talk at insulin/IGF receptors | Avoid; monitor glucose closely if any use is contemplated |
| Growth hormone, GH secretagogues (CJC-1295, ipamorelin) | Additive anabolic and insulin-resistance signaling | Combination amplifies hypertrophy and side-effect risk; medical supervision essential |
| Anti-diabetic agents | Potentiated glucose lowering | Adjust hypoglycemic therapy under physician guidance |
| Active cancer therapy | IGF-1R signaling can promote tumor growth | Contraindicated in patients with active or recent malignancy |
Storage & handling
Lyophilized (powder)
- • Store at -20°C to 4°C (freezer or refrigerator)
- • Protect from light and moisture
- • Stable for 12–24 months when stored properly
- • Keep in original sealed container until reconstitution
Reconstituted solution
- • Refrigerate at 2–8°C after reconstitution
- • Use bacteriostatic water for multi-dose reconstitution
- • Typical stability: 14–28 days refrigerated
- • Do not freeze reconstituted solution
Cost & availability
| Source | Cost | Notes |
|---|---|---|
| Research suppliers | Varies widely | Quality and purity vary significantly between sources |
| Compounding pharmacies | Prescription required | Higher quality assurance and purity testing |
The bottom line
IGF-1 DES is a anabolic compound with research interest in muscle growth, igf-1, recovery, anabolic. While preclinical evidence is encouraging, it remains investigational and is not FDA-approved. Any use should be under qualified medical supervision.
Best for
- • Researchers studying anabolic processes and muscle development
- • Individuals interested in muscle growth under medical guidance
Not for
- • Self-administration without medical supervision
- • Pregnant or breastfeeding individuals
- • Individuals with contraindicated conditions
Related compounds
Frequently asked questions
References
- [1] Sara VR, Carlsson-Skwirut C, Bergman T, et al.. Identification of Gly-Pro-Glu (GPE), the aminoterminal tripeptide of IGF-1 truncated in brain. Biochem Biophys Res Commun (1989). doi: 10.1016/0006-291X(89)92505-6 PMID: 2774322
- [2] Tomas FM, Knowles SE, Owens PC, et al.. IGF-I and especially IGF-I variants are anabolic in dexamethasone-treated rats. Biochem J (1992). doi: 10.1042/bj2820091 PMID: 1540126
- [3] Yakar S, Adamo ML.. Insulin-like growth factor 1 physiology: lessons from mouse models. Endocrinol Metab Clin North Am (2012). doi: 10.1016/j.ecl.2012.04.008 PMID: 22682629