IGF-1
Also known as: IGF-1, Insulin-like Growth Factor 1
IGF-1 is a 70-amino-acid peptide hormone that mediates most of the anabolic and growth-promoting effects of growth hormone. It is studied for muscle growth, tissue repair, and metabolic signaling.
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Mechanism of Action
IGF-1 binds the IGF-1 receptor (IGF-1R), a transmembrane receptor tyrosine kinase, triggering autophosphorylation and recruitment of IRS-1 and Shc adaptor proteins. This activates the PI3K/Akt/mTOR pathway to drive protein synthesis and cell survival, and the Ras/MAPK pathway to drive proliferation. Circulating IGF-1 is largely produced in the liver under GH stimulation and is buffered by IGF-binding proteins (notably IGFBP-3) that modulate its half-life and bioavailability.
- Half-life
- Roughly 10-15 minutes free, but up to 12-16 hours when bound to IGFBP-3 in circulation
- Administration Routes
- subcutaneous
- Research Status
- Research Chemical
Reported Benefits
- Stimulates skeletal muscle protein synthesis and hypertrophy
- Promotes satellite cell activation and myofiber repair
- Supports connective tissue and tendon remodeling
- Enhances glucose uptake and insulin sensitivity in some models
- May aid neuronal survival and growth signaling
Potential Side Effects
- Hypoglycemia from insulin-like activity
- Joint pain and fluid retention
- Localized lipohypertrophy at injection sites
- Theoretical promotion of abnormal tissue growth with chronic use
Common Dosing
For research use only, not medical advice. Animal and in-vitro protocols typically reference 20-100 mcg per day subcutaneously; exact research dosing varies by model and is not a personal-use recommendation.
The dosing information above is aggregated from research literature and anecdotal community reports for educational purposes only. It is not a recommendation, prescription, or medical advice. Peptides are sold as research chemicals only and are not intended for human use.
Contraindications
- Active or history of malignancy
- Diabetic retinopathy or uncontrolled hypoglycemia risk
- Pregnancy and breastfeeding
IGF-1 LR3
IGF-1 LR3 (Long R3 IGF-1) is an engineered, long-acting analog of insulin-like growth factor 1 studied for sustained anabolic and tissue-growth signaling. Its modifications give it a far longer half-life than native IGF-1.
IGF-1 DES
IGF-1 DES is a truncated variant of insulin-like growth factor 1 missing the first three N-terminal amino acids, studied for potent, localized anabolic and tissue-growth effects. It is noted for higher activity at the site of injection.
MGF (Mechano Growth Factor)
MGF is a splice variant of IGF-1 produced locally in muscle in response to mechanical loading or damage. It is studied for its role in activating muscle stem cells and supporting tissue repair.
PEG-MGF
PEG-MGF is a pegylated form of Mechano Growth Factor engineered for greater stability and a longer systemic half-life than native MGF. It is studied for muscle stem cell activation and recovery.
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A randomized, double blind, placebo-controlled trial on safety and efficacy of recombinant human insulin-like growth factor-I in children with growth hormone receptor deficiency
1995
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Insulin-like growth factor 1 and muscle growth: implication for satellite cell proliferation
2004
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The IGF-I receptor in cell growth, transformation and apoptosis
1997
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Insulin-like growth factor in muscle growth and its potential abuse by athletes
2000