IGF-1 lr3

Long R3 IGF-1, LR3-IGF-1, Insulin-like Growth Factor-1 Long Arg3

A synthetic analog of IGF-1 with extended half-life, promoting muscle growth, cell proliferation, tissue repair, and metabolic effects.

Molecular Profile

Formula C₄₀₀H₆₂₅N₁₁₁O₁₁₅S₉

Mol. Weight 9117.60 g/mol

Sequence Gly-Glu-Pro-Pro...

Clinical Data Trials

Scientific Data Studies

Route	Dosage	Bioavailability
Subcutaneous (SC) 20-50 mcg/day	20-50 mcg/day	High (95%)	SUB
Intramuscular (IM) 20-50 mcg/day	20-50 mcg/day	High (95%)	INT

How It Works

How It Works: IGF-1 LR3 acts by binding to IGF-1 receptors on cell surfaces, activating intracellular signaling pathways that promote growth, survival, and metabolic processes.

Receptor Binding: Binds to IGF-1R, activating PI3K/Akt and MAPK pathways for protein synthesis and cell proliferation.
Muscle Growth: Induces hypertrophy and hyperplasia by enhancing myoblast differentiation and fusion.
Metabolic Effects: Improves glucose uptake, promotes lipolysis, and inhibits protein breakdown.
Anti-Apoptotic: Prevents cell death and supports tissue repair and regeneration.

Pairs Well With

Latest Studies

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Utility 3

pubmed Sep 25, 2025

Revolutionary decellularized Alstroemeria stem-based nerve conduit integrated with GelMA and controlled IGF-1 LR3 release for enhanced rat sciatic nerve regeneration.

Yavuz. Ersin E; Sağır. Melih S MS; Ercan. Alp A; Erginer. Merve M; B...

A new nerve tube made from a plant stem and a gel was tested in rats with a small sciatic nerve gap. It slowly released the peptide IGF‑1 LR3, which helped nerves grow back as well as the current gold‑standard nerve graft, and it didn’t cause any obvious side effects.

Utility 1

pubmed Dec 16, 2024

IGF-1 LR3 does not promote growth in late-gestation growth-restricted fetal sheep.

White. Alicia A; Stremming. Jane J; Wesolowski. Stephanie R SR; Al-Juboori. Saif...

In a study on sheep fetuses that were not growing well because of a weak placenta, giving them IGF‑1 LR3 for a week did not make them bigger, nor did it change their insulin or sugar‑handling. It did lower their blood amino acids, which might mean the bodies used more building blocks, but overall the treatment didn’t help the growth problem.

Utility 2

pubmed Nov 29, 2024

Intranasal long R3 insulin-like growth factor-1 treatment promotes amyloid plaque remodeling in cerebral cortex but fails to preserve cognitive function in male 5XFAD mice.

Engel. Matthew G MG; Narayan. Sushma S; Cui. Min-Hui MH; Branch. Craig A CA; Zha...

Giving mice a nasal spray of a strong IGF‑1 version (LR3‑IGF‑1) changed the shape of Alzheimer‑related plaques in the brain and made the mice a bit leaner, but it didn’t help them think better or remember things. The drug helped break down harmful small amyloid pieces and made plaques look more inert, yet memory stayed the same.

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