IGF-1 LR3
Fat Loss & Body Composition

IGF-1 LR3

Price range: $108.00 through $488.00

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$10.80
10 vials per pack
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$32.40
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IGF-1 LR3 - Long Arg3 IGF-1 Analog Research Peptide

IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a synthetic 83-amino-acid analog of native IGF-1 with two modifications: a 13-amino-acid N-terminal extension (the “Long” segment) and an arginine substitution at position 3 that replaces the native glutamate. Both modifications reduce binding to IGF binding proteins (IGFBPs), which extends the peptide’s circulating half-life from roughly 10-20 minutes (native IGF-1) to around 20-30 hours. IGF-1 LR3 is the reference research analog for studying sustained IGF-1 receptor (IGF-1R) activation without the rapid IGFBP sequestration that limits native IGF-1 in vivo.

Why the IGFBP-Resistant Profile Matters

In circulation, roughly 99% of native IGF-1 is bound to IGFBPs (primarily IGFBP-3) and only a small free fraction is bioactive. The Arg3 substitution in IGF-1 LR3 drops IGFBP affinity substantially, and the N-terminal extension further blocks binding-protein association. The result is a peptide that stays free and bioactive for an extended window - which is the specific property research protocols are after when they need sustained IGF-1R signaling rather than a short pulse.

Pathway What it does in plain terms
IGF-1 receptor (IGF-1R) Agonized - triggers PI3K/Akt and MAPK signaling cascades
IGFBPs (1-6) Bypassed - Arg3 and N-terminal extension reduce binding-protein sequestration
Satellite-cell activation Promoted in published skeletal-muscle hypertrophy research
Glucose uptake IGF-1R crossover with insulin receptor supports glucose disposal
Plasma half-life ~20-30 hours (vs ~10-20 minutes for native IGF-1)

IGF-1 LR3 vs IGF-1 DES vs Native IGF-1

The three IGF-1 research variants are compared regularly in hypertrophy and regeneration literature. Each modifies a different structural feature of the native sequence.

Variant Modification Research profile
Native IGF-1 None Short half-life; heavily IGFBP-bound
IGF-1 LR3 N-terminal extension + Arg3 substitution Extended half-life; systemic IGF-1R signaling
IGF-1 DES (1-3) N-terminal tripeptide removed Ultra-short half-life; localized signaling

Research Applications

IGF-1 LR3 is used in studies examining:

  • IGF-1 receptor agonism and PI3K/Akt signaling endpoints
  • Satellite-cell activation and skeletal-muscle hypertrophy research
  • Extended IGF-1R activation (vs native IGF-1’s short pulse)
  • Comparative research vs IGF-1 DES and native IGF-1
  • Paired research with GH-axis compounds (sermorelin, tesamorelin, CJC-1295)
  • Cellular glucose uptake and IGF-1R / insulin-receptor cross-talk

Specifications
Format Lyophilized powder
Purity ≥99%
Aliases Long R3 IGF-1, Long Arg3 IGF-1, IGF-I LR3
Available sizes 0.1mg · 1mg
Storage 2-8°C unopened; stable 12+ months
Use Research purposes only - not for human use

Storage & Handling

Unopened vials are kept at 2-8°C under standard cold-chain conditions and remain stable for 12+ months. Reconstitution parameters, solvent compatibility, and post-reconstitution stability for IGF-1 LR3 are documented in the published peer-reviewed literature and standard peptide-chemistry references.

Reference Literature

Published clinical and preclinical IGF-1 LR3 literature is available through PubMed, Google Scholar, and other peer-reviewed databases. WWP does not provide protocol design, dosing guidance, or administration parameters. Those decisions rest with the researcher and any applicable institutional review board.

Common Questions About IGF-1 LR3 Research

What is IGF-1 LR3 used for in research?

It is studied as the long-acting IGF-1R agonist. Published work covers PI3K/Akt and MAPK signaling, satellite-cell activation, skeletal-muscle hypertrophy endpoints, cellular glucose uptake research, and comparative work against IGF-1 DES and native IGF-1.

What is the difference between IGF-1 LR3 and native IGF-1?

IGF-1 LR3 carries two modifications - a 13-amino-acid N-terminal extension and an arginine substitution at position 3 - that dramatically reduce IGF binding protein (IGFBP) affinity. The result is an extended plasma half-life (20-30 hours vs 10-20 minutes for native IGF-1) and sustained IGF-1 receptor activation in circulation.

How does IGF-1 LR3 compare to IGF-1 DES?

IGF-1 LR3 has an extended half-life and produces systemic IGF-1R signaling. IGF-1 DES (1-3) has the N-terminal tripeptide removed, which gives it ultra-short half-life and localized signaling. Research designs choose between them based on whether the study question requires sustained exposure or a highly localized pulse.

Is IGF-1 LR3 FDA approved?

No. IGF-1 LR3 is not FDA approved for any use. Recombinant native IGF-1 (mecasermin) is FDA approved for severe primary IGF-1 deficiency, but the LR3 analog is not. It is also prohibited under the WADA Prohibited List. Every vial WWP ships is labeled and sold strictly for laboratory and research use only.

How is IGF-1 LR3 stored?

Unopened vials are stored at 2-8°C and stay stable for 12+ months. Once reconstituted with bacteriostatic water, the solution is kept at 2-8°C and used within 28-30 days.

Purity Guarantee

Every batch is ≥99% purity. Send us a COA from any independent test and we’ll issue store credit regardless of what it shows.

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