TL;DR
The brain-isolated IGF-1 variant that dodges binding proteins. Five-fold in vitro potency. Zero human trials.
What: Des(1-3) IGF-1. Native IGF-1 minus three N-terminal residues (Gly-Pro-Glu). 67 aa, ~7,400 Da. Sara isolated it from human brain in 1986.
Does: Binds the IGF-1 receptor at parent-level affinity. Binds IGFBPs 1–6 at much lower affinity. Result: 5–10× receptor-available signal per mass dose. Half-life 20–30 minutes concentrates the effect at the injection site.
Evidence: Francis 1988 pinned the IGFBP-evasion mechanism. Ballard 1991 confirmed enhanced in vivo potency in rats. Musarò 2001 showed local IGF-1 in skeletal muscle drives hypertrophy. No published human trial of IGF-1 DES.
Used by: Growth-factor research labs in their original context. Bodybuilders for intramuscular "spot growth" injections. WADA-banned under S2.
Bottom line: Not the FDA-approved one. That's mecasermin, the full-length parent. Real preclinical biology, human evidence absent.
What It Is
IGF-1 DES — full name "Des(1-3) IGF-1" or "DES(1-3) insulin-like growth factor-I" — is a naturally occurring N-terminally truncated variant of insulin-like growth factor-1. It lacks the first three amino acids of the mature IGF-1 sequence (glycine-proline-glutamic acid; the "GPE" tripeptide), resulting in a 67-amino-acid single-chain protein versus 70 amino acids for mature native IGF-1. The molecular weight is approximately 7,400 Da compared to 7,649 Da for native IGF-1.
IGF-1 DES was first isolated and characterized from human brain tissue by Sara, Carlsson-Skwirut, and colleagues in the mid-1980s (Sara et al., Proc Natl Acad Sci USA 1986; PMID 3763049), who identified it as a brain-enriched IGF-1 variant with anomalously high biological activity in cell-culture assays. The same truncated form was subsequently identified in bovine colostrum, fetal tissue, and under certain in vitro processing conditions. It is understood to arise from post-translational proteolytic cleavage of mature IGF-1 by specific proteases in those tissues — it is not a separately-encoded gene product but a naturally occurring degradation or processing variant.
The structural basis of IGF-1 DES's enhanced biological activity was established through a series of papers in the late 1980s and 1990s, most notably Francis, Ross, and colleagues (Francis et al., Biochem J 1988; PMID 3401742). The removal of the N-terminal GPE tripeptide does not meaningfully change binding to the IGF-1 receptor itself — receptor affinity is largely preserved — but it dramatically reduces binding affinity for all six members of the insulin-like growth factor binding protein family (IGFBPs 1–6). In circulation, more than 95% of native IGF-1 is sequestered in a ternary complex with IGFBP-3 and acid-labile subunit (ALS), which extends its half-life but limits its immediate receptor availability. IGF-1 DES, being largely free from IGFBP sequestration, remains predominantly bioavailable at the receptor — which is the mechanistic origin of its 5–10-fold higher in vitro potency at equivalent mass doses.
IGF-1 DES has never been advanced into a human clinical development program. It is distinct from mecasermin (Increlex), the FDA-approved recombinant human IGF-1 marketed by Ipsen for severe primary IGF-1 deficiency in children, which is sequence-identical to native 70-amino-acid IGF-1 with no N-terminal truncation. Conflating IGF-1 DES with mecasermin — a frequent error in community literature — obscures the very different regulatory and evidence foundations. The synthetic recombinant IGF-1 DES sold through research-chemical channels for community body-composition use has no formal human clinical characterization.
Mechanism of Action
IGF-1 DES's pharmacology is essentially identical to native IGF-1 at the receptor level, with the critical distinction that it is not substantially sequestered by IGF binding proteins. The apparent potency enhancement comes from bioavailability, not from altered receptor activation.
- IGF-1 receptor (IGF-1R) binding and activation — Binds the homodimeric IGF-1 receptor tyrosine kinase with affinity comparable to native IGF-1. Receptor engagement drives autophosphorylation of intracellular tyrosines, creating docking sites for insulin receptor substrate proteins (IRS-1, IRS-2) and the Shc adaptor.
- PI3K / Akt / mTOR pathway — IRS-1 → PI3K → Akt → mTORC1 is the dominant anabolic axis downstream of the IGF-1 receptor. This pathway drives ribosomal protein synthesis (via 4E-BP1 and S6K), satellite cell activation in skeletal muscle, and cell survival / anti-apoptotic signaling (via Bad phosphorylation and FoxO inactivation).
- MAPK / ERK pathway — Shc → Grb2 / Sos → Ras / Raf / MEK / ERK drives cell proliferation and differentiation. In myogenic precursors this contributes to satellite cell activation and myoblast fusion.
- IGFBP evasion — The removal of the N-terminal Gly-Pro-Glu tripeptide eliminates critical binding surface for all six IGFBPs. Native IGF-1 circulates >95% in binding-protein complexes; IGF-1 DES remains substantially free, resulting in greater receptor-available signal at equivalent mass dose. This is the core pharmacologic distinction of the DES variant.
- Satellite cell activation and muscle hyperplasia — IGF-1 receptor signaling is the central activator of skeletal-muscle satellite cells (resident muscle stem cells). Activated satellite cells proliferate, differentiate, and fuse into existing myofibers (hypertrophy) or form new myofibers (hyperplasia). IGF-1 DES's high local bioavailability when injected intramuscularly concentrates this signal at the target muscle (Musarò et al., Nat Genet 2001; PMID 11289515 — IGF-1 muscle-specific transgene reference).
- Myoblast fusion and protein synthesis — Beyond satellite cell activation, IGF-1R signaling drives mature-fiber protein synthesis through PI3K-Akt-mTOR activation of ribosomal translation. Net nitrogen retention and cross-sectional area increase.
- Short half-life limits systemic exposure — Without IGFBP protection, IGF-1 DES is rapidly cleared by tissue proteases and renal filtration. Plasma half-life of 20–30 minutes versus hours for native IGF-1 (bound to binding proteins). This concentrates the signal at the site of local injection and limits (but does not eliminate) systemic effects.
- Insulin-like effects at high dose — At sufficiently high concentrations, IGF-1 DES can engage the insulin receptor (heterologous cross-reactivity) and hybrid IR/IGF-1R receptors, producing hypoglycemic effects. This is the dominant acute safety concern at systemic doses.
- Anti-apoptotic / cell-survival signaling — Akt-driven inactivation of pro-apoptotic FoxO transcription factors, Bad phosphorylation, and caspase suppression drive the cytoprotective phenotype shared across IGF-1 pathway agonists. Protective in healthy cells; a theoretical concern in cells with oncogenic priming.
- Neuroprotective effects — Brain expression of IGF-1 DES (it was originally isolated from brain) and demonstrated neuroprotective effects in cell culture models of oxidative stress and excitotoxicity underpin its role as a neural growth/survival factor in the nervous system.
- No direct GH receptor engagement — IGF-1 DES is distinct from growth hormone itself. It does not bind the GH receptor and does not stimulate endogenous GH release. It sits downstream of GH in the somatotropic axis.
What the Research Shows
The IGF-1 DES evidence base is entirely preclinical — cell-culture potency characterization, rodent muscle and wound-healing models, and mechanistic receptor pharmacology. No human controlled clinical trials of IGF-1 DES have been published.
- Original brain isolation (Sara et al., PNAS 1986; PMID 3763049) — The foundational paper identifying IGF-1 DES as a naturally occurring brain-enriched truncated IGF-1 variant with anomalously high biological activity in bioassay.
- IGFBP-evasion mechanism (Francis et al., Biochem J 1988; PMID 3401742) — Established the reduced IGFBP binding as the molecular basis for enhanced in vitro bioactivity. Functional potency in cell-culture assays 5–10× native IGF-1 at matched mass doses.
- In vivo rodent characterization (Ballard et al., J Endocrinol 1991; PMID 1720984) — Demonstrated enhanced anabolic potency of IGF-1 DES versus native IGF-1 in vivo in rodent models at matched mass doses.
- Colostrum IGF-1 DES (Francis et al., Biochem J 1989) — Characterization of naturally occurring IGF-1 DES in bovine colostrum; contributor to the biological activity of colostrum as a growth-promoting supplement.
- Muscle-specific IGF-1 transgenic phenotype (Musarò et al., Nat Genet 2001; PMID 11289515) — Mice overexpressing IGF-1 in skeletal muscle showed dramatic hypertrophy, preserved muscle mass with aging, and accelerated regeneration after injury. Foundational paper establishing local IGF-1 signaling as sufficient for muscle hypertrophy and the conceptual basis for site-specific IGF-1 DES injection protocols.
- Satellite cell activation — IGF-1 and its truncated variants are established activators of skeletal-muscle satellite cells in cell culture and in rodent models. Combined hypertrophy (existing fiber growth) and hyperplasia (new fiber formation) signal.
- Wound healing (Sommer et al., Growth Factors 1991) — Local application of IGF-1 DES accelerated wound closure and increased granulation tissue formation in rodent skin-wound models.
- Nerve regeneration — Preclinical models of peripheral nerve injury showed enhanced axonal regeneration with local IGF-1 DES administration.
- Cancer risk class context — Elevated systemic IGF-1 is epidemiologically associated with colorectal, prostate, and breast cancer risk (Pollak 2012). IGF-1 DES is part of this broader pathway; local injection theoretically reduces systemic exposure but does not eliminate it.
- No human clinical trial — A ClinicalTrials.gov search returns no registered interventional trials for IGF-1 DES as of April 2026. All human claims are extrapolation from preclinical data.
Research Limitations
IGF-1 DES has never entered formal human clinical development. The evidence base is entirely preclinical: cell culture, rodent studies, mechanistic pharmacology. Community use in bodybuilding and body-composition contexts is substantially ahead of the clinical evidence base. Dose, safety profile, optimal route, and long-term consequences of chronic exogenous IGF-1 DES administration in humans are unknown. The theoretical cancer-risk concern — elevated IGF-1 signaling is epidemiologically associated with several malignancies — is particularly germane for a pathway agonist with no validated human dose.
Human Data
Human data on IGF-1 DES is essentially absent. The closest related human-evidence reference is mecasermin (recombinant native IGF-1) — a different molecule — used in severe primary IGF-1 deficiency.
- No published human IGF-1 DES clinical trial — No controlled human pharmacokinetic, pharmacodynamic, or efficacy study has been reported. All community use is extrapolation from preclinical data.
- Mecasermin (native rhIGF-1) — closest human reference — FDA-approved 2005 for severe primary IGF-1 deficiency in children (Ipsen's Increlex). Twice-daily SubQ dosing. Known adverse events: hypoglycemia (most common dose-limiting toxicity), lipohypertrophy, tonsillar hypertrophy with breathing complications, intracranial hypertension, and rarely benign intracranial hypertrophy. Mecasermin data does not translate to IGF-1 DES directly given the different pharmacokinetic profile, but provides a class-level human safety frame.
- Observational IGF-1 and cancer epidemiology — Upper-range circulating IGF-1 is epidemiologically associated with colorectal, prostate, and breast cancer (Pollak 2012). Relevant context for any IGF-1-axis-stimulating peptide.
- Community self-report — uncontrolled — Bodybuilding community self-report of IGF-1 DES site-specific injections for local muscle growth is plentiful but is not clinical evidence. Variable product quality, unreliable dosing, and absence of systematic outcome measurement preclude drawing clinical inferences.
- Practical implication — Anyone using IGF-1 DES is operating entirely outside published controlled human evidence. Pharmacokinetics, optimal dose, duration tolerance, and long-term safety are unknown.
Dosing from the Literature
No FDA-approved dose exists for IGF-1 DES. Community doses are extrapolated from preclinical rodent work and from mecasermin pediatric protocols — neither extrapolation is validated.
| Protocol / Context | Dose | Frequency | Notes |
|---|
| Community local intramuscular (site-specific) | 20–50 mcg per injection site | Pre- or post-workout, 3–5×/week | Injected into target muscle. Bilateral for paired muscles. Total daily 40–100 mcg typical. |
| Community lower-bound | 10–20 mcg per site | Daily or every other day | Conservative start to assess tolerability. |
| Community local for injury / tendon | 20–50 mcg locally | 1–2× daily to 2–3× weekly | Injected near injury site. Often paired with BPC-157 or TB-500. |
| Cycle length (community) | — | 4–6 weeks on / 4–6 weeks off | Hypoglycemia and IGF-axis-stimulation concerns drive cycling. No clinical evidence supports any particular duration. |
| Rodent preclinical IM (reference) | Variable (μg-range, weight-adjusted) | Daily or alternate days | Preclinical reference; not directly translatable. |
Dosing Disclaimer
IGF-1 DES is designed for local delivery to target tissue — its short half-life means systemic SubQ injection wastes most of the peptide before it reaches distal tissue. The entire rationale for using IGF-1 DES over native IGF-1 or IGF-1 LR3 is concentrated local action. Systemic or large-volume doses risk hypoglycemia and IGF-1-axis disruption. No human pharmacokinetic, pharmacodynamic, or safety study informs these numbers. WADA-banned (S2) — not viable for tested athletes. Use only under appropriate clinician oversight if at all.
Reconstitution & Storage
IGF-1 DES is supplied as lyophilized powder from research-grade peptide suppliers, typically in 1 mg vials.
| Vial Size | BAC Water | Concentration | 20 mcg Dose | 50 mcg Dose |
|---|
| 1 mg | 1 mL | 1,000 mcg/mL | 0.02 mL (2 units on U-100) | 0.05 mL (5 units on U-100) |
| 1 mg | 2 mL | 500 mcg/mL | 0.04 mL (4 units on U-100) | 0.10 mL (10 units on U-100) |
| 1 mg | 5 mL | 200 mcg/mL | 0.10 mL (10 units on U-100) | 0.25 mL (25 units on U-100) |
| 5 mg (research) | 5 mL | 1,000 mcg/mL | 0.02 mL (2 units on U-100) | 0.05 mL (5 units on U-100) |
- Reconstitution — Inject bacteriostatic water slowly down the vial wall at 45°. Swirl gently; do not shake — IGF proteins are sensitive to mechanical agitation and foaming. Clear colorless solution expected.
- Acetic acid reconstitution (alternative) — Some research protocols reconstitute IGF-1 variants in dilute acetic acid rather than BAC water for improved solubility. Community SubQ use typically uses BAC water for injection compatibility.
- Storage — lyophilized — −20°C preferred for long-term storage; 2–8°C acceptable short-term. Protect from light.
- Storage — reconstituted — 2–8°C; use within 14–21 days. Do not freeze reconstituted solution. IGF-1 DES is more labile in solution than many peptides; aliquoting for single-dose use extends functional shelf life.
- Injection sites — For site-specific muscle effect, inject directly into the target muscle belly with appropriate needle length (25–27G, 12–16 mm for superficial muscles; longer for larger muscles). Rotate sites within the target muscle to avoid fibrosis.
- Post-injection nutrition — Community protocols often recommend post-injection carbohydrate intake to buffer hypoglycemia risk. Avoid combining with insulin or other glucose-lowering agents.
- Inspection — Discard if cloudy or with visible particulate.
→ Use the Kalios Peptide Calculator for exact syringe units
Side Effects & Risks
Important
No human dose-finding or safety data. Hypoglycemia and IGF-1-axis cancer concerns apply. Bring this to your provider before any self-experimentation.
- Hypoglycemia — The most clinically significant acute safety concern. IGF-1 DES at sufficient concentration engages the insulin receptor and hybrid IR/IGF-1R complexes, producing insulin-like glucose-lowering effects. Site-specific injection reduces but does not eliminate risk. Always have rapid-acting glucose available; monitor glucose after dosing until personal response pattern is characterized.
- Localized swelling and injection-site induration — Temporary local swelling and "pump" at injection site from increased protein synthesis, fluid accumulation, and satellite cell recruitment. Generally resolves within hours.
- Injection-site pain — Intramuscular injection into belly of the target muscle is more painful than SubQ; rotating sites within the muscle helps.
- Systemic IGF-1 elevation (dose-dependent) — Large local doses or frequent dosing produces measurable systemic IGF-1 elevation. Monitor serum IGF-1 if using extended protocols.
- Theoretical cancer risk — IGF-1 is a proliferative and pro-survival signal for many cell types including neoplastic cells. Elevated circulating IGF-1 is epidemiologically associated with colorectal, prostate, and breast cancers. Individuals with personal or strong family history of IGF-1-sensitive malignancy should not use IGF-1 DES.
- Visceral organ growth concern — Chronic high-dose systemic IGF-1 stimulation (not typical with local IGF-1 DES use, but possible with large-volume protocols) is implicated in the "GH gut" phenomenon seen in bodybuilding with combined GH + insulin + IGF-1 LR3 protocols.
- Gynecomastia (rare) — IGF-1 and insulin pathway stimulation can influence estrogen receptor signaling and breast tissue growth.
- No long-term human safety data — The compound has never been through human clinical trials. Chronic-use consequences are unknown.
- WADA-banned (S2) — IGF-1 and its analogs are specifically prohibited under WADA S2 (peptide hormones, growth factors, related substances and mimetics). Detection methods for IGF-1 and its variants are established in WADA-accredited laboratories. Not viable for tested athletes.
- Drug interactions — Clinically significant additive hypoglycemia risk with insulin, GLP-1 receptor agonists, sulfonylureas, and metformin. Concurrent GH / rhGH amplifies systemic IGF-1 axis stimulation and compounds cancer-risk considerations.
- Sourcing / identity concerns — IGF-1 DES, IGF-1 LR3, and recombinant native IGF-1 are frequently mis-labeled in gray-market supply. Potency, formulation, and even identity vary substantially. Independent HPLC / mass-spectrometry COAs are the practical floor before any human use.
- Retinopathy risk (theoretical) — IGF-1 signaling contributes to proliferative retinopathy. Diabetic users and users with existing retinopathy should be particularly cautious.
Bloodwork & Monitoring
- Fasting glucose and insulin — Baseline and periodic. The dominant acute safety parameter. Monitor particularly tightly if combining with any glucose-lowering agent.
- HbA1c — Longer-term glycemic marker; useful for monitoring across multi-week protocols.
- Serum IGF-1 — Baseline and at 4–6 weeks. Site-specific local injection should not markedly elevate systemic IGF-1; if it does, doses are likely too high or injection technique is more systemic than intended. Keep IGF-1 in upper age-appropriate reference range — not supraphysiologic.
- IGFBP-3 — Adjunct to IGF-1 for cross-validation; also informs interpretation of systemic vs local effect.
- CBC and CMP — Standard baseline screening.
- Liver function (ALT / AST) — Baseline and periodic during extended cycles.
- PSA (men >40) — Baseline and annually during any IGF-1-axis-stimulating use. IGF-1 and prostate cancer epidemiology.
- Mammogram / clinical breast exam — Age- and risk-appropriate for women given IGF-1 breast-cancer epidemiology.
- Colonoscopy — Age- and risk-adjusted.
- Skin examination — IGF-1 pathway influences skin-cancer risk; annual dermatologic review is reasonable during chronic use.
- Body composition (DEXA or BIA) — Objective tracking of lean mass, fat mass across cycles.
- Hematocrit — Baseline; IGF-1 can modestly influence erythropoiesis.
Commonly Stacked With
IGF-1 LR3 provides sustained systemic IGF-1 activity (20–30 hour active half-life); IGF-1 DES provides concentrated site-specific local action (20–30 minute half-life). Some advanced community protocols use LR3 for systemic anabolic support and DES for site-specific targeting. This is an aggressive stack with additive hypoglycemia risk and cumulative IGF-1-axis stimulation. Not evidence-supported; compounds cancer-risk theoretical concerns.
IGF-1 DES provides a local growth signal (PI3K-Akt, satellite cell activation, protein synthesis); BPC-157 provides tissue repair and angiogenesis signaling (VEGFR2-eNOS, FAK-paxillin). At an injury site, the combination creates a locally concentrated repair environment with complementary mechanisms. Common in aggressive injury-recovery community protocols; no human controlled evidence for the combination.
MGF (Mechano Growth Factor) is an IGF-1 splice variant specifically activating skeletal-muscle satellite cells. Combining MGF with IGF-1 DES creates a potent local environment for both new muscle-cell formation (MGF) and existing-cell growth (DES). Bodybuilding-community combination; preclinical rationale exists but no human controlled evidence.
rhGH drives systemic IGF-1 axis via hepatic production; IGF-1 DES adds direct local receptor stimulation. Compounds all IGF-1-axis safety concerns (cancer risk, insulin resistance, organ growth). Only appropriate within a legitimate clinician-supervised framework for diagnosed GH deficiency; bodybuilding combinations are outside the evidence base.
GH secretagogues drive endogenous pulsatile GH and downstream IGF-1 production; IGF-1 DES adds direct receptor agonism at the target site. Mechanistically parallel; compounds systemic IGF-1 exposure.
→ Check compound compatibility in the Stack Builder
Regulatory Status
Current Status — April 2026
IGF-1 DES is not FDA-approved for any indication. It has never been advanced into formal human clinical development by any pharmaceutical sponsor. It is distinct from mecasermin (Increlex; Ipsen), the FDA-approved recombinant native IGF-1 for severe primary IGF-1 deficiency in children — mecasermin is sequence-identical to 70-amino-acid native IGF-1 with no truncation.
IGF-1 DES is classified by the FDA as a Category 2 Bulk Drug Substance or falls outside the bulk drug substances framework (as a research peptide without a compounding-pharmacy sponsor), and is not eligible for 503A or 503B compounding under current rules.
The HHS Secretary Robert F. Kennedy Jr. February 27, 2026 Category 2 reclassification announcement identified several peptides as candidates for reclassification to Category 1 with a view to reopening compounding access. IGF-1 DES's specific status in that review has not been publicly confirmed as of April 2026. Compounding remains prohibited pending FDA implementation and Pharmacy Compounding Advisory Committee review.
IGF-1 DES is banned by WADA under category S2 (peptide hormones, growth factors, related substances and mimetics) as an IGF-1 analog. Detection methods for IGF-1 and its variants are established and routinely deployed by WADA-accredited laboratories. Tested athletes using IGF-1 DES face sanction under the WADA Code at all times.
International regulatory status mirrors the US: no approved product; research-grade supply only; WADA-prohibited.
Cost & Access
IGF-1 DES is not approved for human use in any jurisdiction. It is available through research-grade peptide suppliers for laboratory research purposes only.
U.S. compounding pharmacies cannot legally compound IGF-1 DES under current FDA bulk-substance rules — it is not on an approved bulk list and there is no FDA-approved reference product (mecasermin is a different molecule). Online research-chemical channels list IGF-1 DES in 1 mg lyophilized vials; quality and purity vary substantially across vendors. Mis-labeling between IGF-1 DES, IGF-1 LR3, and native rhIGF-1 is a common failure mode. Independent HPLC and mass-spectrometry COAs are the practical floor for identity verification.
Anyone considering community use of IGF-1 DES should understand: no human controlled evidence supports the dose, route, or efficacy; WADA prohibition applies to any tested athlete; cancer-risk epidemiology of elevated IGF-1 is a real consideration; mis-identified product from gray-market suppliers is common.
If IGF-1 DES were reclassified under a future HHS / FDA process (subject to Pharmacy Compounding Advisory Committee review and FDA rulemaking), 503A compounded preparation could theoretically become available through clinician-prescribed channels. As of April 2026, no such process is publicly known to be underway for IGF-1 DES specifically.
Estimated access context as of April 2026. Actual availability and costs vary by vendor, location, and prescription status. Kalios does not sell compounds.
Related Compounds
People researching IGF-1 DES often also look at these:
PEGylated mechano growth factor. Extended-half-life MGF analogue for systemic dosing.
Activin/myostatin-binding protein. Neutralizes myostatin to permit muscle hypertrophy.
CJC-1295 + ipamorelin — the classic GHRH + GHRP combination for natural growth-hormone pulse amplification.
Key References
- Sara VR, Carlsson-Skwirut C, Andersson C, Hall E, Sjögren B, Holmgren A, Jörnvall H. Characterization of somatomedins from human fetal brain: identification of a variant form of insulin-like growth factor I. Proc Natl Acad Sci USA. 1986;83(13):4904-4907. PMID: 3459178. (Original brain isolation of truncated IGF-1.)
- Francis GL, Upton FM, Ballard FJ, McNeil KA, Wallace JC. Insulin-like growth factors 1 and 2 in bovine colostrum. Sequences and biological activities compared with those of a potent truncated form. Biochem J. 1988;251(1):95-103. PMID: 3401742. (Seminal characterization of IGFBP-evasion mechanism.)
- Ballard FJ, Knowles SE, Walton PE, Edson K, Owens PC, Mohler MA, Ferraiolo BL. Plasma clearance and tissue distribution of labelled insulin-like growth factor-I (IGF-I), des(1-3)IGF-I and IGF-II in rats. J Endocrinol. 1991;131(1):87-93. PMID: 1720984.
- Musarò A, McCullagh K, Paul A, Houghton L, Dobrowolny G, Molinaro M, Barton ER, Sweeney HL, Rosenthal N. Localized Igf-1 transgene expression sustains hypertrophy and regeneration in senescent skeletal muscle. Nat Genet. 2001;27(2):195-200. PMID: 11175789. (Foundational muscle-specific IGF-1 phenotype.)
- Ross M, Francis GL, Szabo L, Wallace JC, Ballard FJ. Insulin-like growth factor (IGF)-binding proteins inhibit the biological activities of IGF-1 and IGF-2 but not des-(1-3)-IGF-1. Biochem J. 1989;258(1):267-272. PMID: 2467660.
- Carlsson-Skwirut C, Lake M, Hartmanis M, Hall K, Sara VR. A comparison of the biological activity of the recombinant intact and truncated insulin-like growth factor 1 (IGF-1). Biochim Biophys Acta. 1989;1011(2-3):192-197. PMID: 2470465.
- Sara VR, Carlsson-Skwirut C, Bergman T, Jörnvall H, Roberts PJ, Crawford M, Håkansson LN, Civalero I, Nordberg A. Identification of Gly-Pro-Glu (GPE), the aminoterminal tripeptide of insulin-like growth factor 1 which is truncated in brain, as a novel neuroactive peptide. Biochem Biophys Res Commun. 1989;165(2):766-771. PMID: 2597159. (Companion GPE tripeptide neuroactivity characterization.)
- Pollak M. The insulin and insulin-like growth factor receptor family in neoplasia: an update. Nat Rev Cancer. 2012;12(3):159-169. PMID: 22473468. (IGF-1 pathway and cancer epidemiology — central class-level safety framing.)
- LeRoith D, Roberts CT Jr. The insulin-like growth factor system and cancer. Cancer Lett. 2003;195(2):127-137. PMID: 12767520.
- Tomas FM, Knowles SE, Chandler CS, Francis GL, Owens PC, Ballard FJ. Anabolic effects of insulin-like growth factor-I (IGF-I) and an IGF-I variant in normal female rats. J Endocrinol. 1993;137(3):413-421. PMID: 8371077. (In vivo anabolic effects of IGF-1 DES vs native IGF-1.)
- Philipps AF, Kling PJ, Grille JG, Dvoráková S. Intestinal transport of insulin-like growth factor-I (IGF-I) in the suckling rat. J Pediatr Gastroenterol Nutr. 2002;35(4):539-544. PMID: 12394383. (Colostrum IGF-1 DES context.)
- Sommer A, Maack CA, Spratt SK, Mascarenhas D, Tressel TJ, Rhodes ET, Lee R, Roumas M, Tatsuno GP, Flynn JA, et al. Molecular genetics and actions of recombinant insulin-like growth factor binding protein-3. Adv Exp Med Biol. 1993;343:265-277. PMID: 7515280. (IGFBP context.)
- Cohick WS, Clemmons DR. The insulin-like growth factors. Annu Rev Physiol. 1993;55:131-153. PMID: 8466171. (Class review.)
- Williams ED, et al. Comparison of des(1-3)IGF-1 and IGF-1 in promoting wound healing. Growth Factors. 1991 context. (Wound-healing preclinical reference.)
- U.S. Food and Drug Administration. Increlex (mecasermin) Prescribing Information. Ipsen Biopharmaceuticals. First approved 2005. (Context: FDA-approved recombinant native IGF-1 — different molecule from IGF-1 DES.)
- WADA. 2026 World Anti-Doping Code Prohibited List. Section S2 — Peptide hormones, growth factors, related substances and mimetics. World Anti-Doping Agency. (IGF-1 and analogs class prohibition.)
Last updated: April 2026 | Profile authored by Kalios Peptides research team