IGF-1 LR3 Research: Concentration-Response and Myocyte Cell Model Studies
IGF-1 LR3 Receptor Pharmacology and Mechanism of Action
IGF-1 Long R3 (LR3) represents a modified analog of insulin-like growth factor-1 with enhanced stability characteristics for in vitro research applications. The compound demonstrates selective binding affinity for IGF-1 receptors while exhibiting reduced interaction with IGF-binding proteins compared to native IGF-1. This structural modification incorporates an N-terminal extension and amino acid substitution at position 3, resulting in prolonged half-life in cell culture systems.
The primary mechanism involves high-affinity binding to IGF-1 receptors, which are transmembrane receptor tyrosine kinases expressed across diverse cell types. Upon ligand binding, the receptor undergoes autophosphorylation and conformational changes that facilitate downstream signal transduction cascade activation. The modified structure of IGF-1 LR3 maintains receptor selectivity while providing extended bioavailability in experimental systems.
Cell Model Systems and Binding Affinity Studies
Myocyte Cell Models
Myocyte cell lines serve as established experimental models for investigating IGF-1 LR3 receptor pharmacology. C2C12 myoblasts and L6 myotubes represent well-characterized systems expressing endogenous IGF-1 receptors with documented binding kinetics. These cell models demonstrate concentration-dependent responses to IGF-1 LR3 exposure, with EC50 values typically ranging from 1-10 nM in standardized binding assays.
Primary myocyte cultures isolated from rodent skeletal muscle provide additional experimental models with physiologically relevant receptor expression profiles. These systems maintain native IGF-1 receptor density and distribution patterns, enabling comprehensive pharmacological characterization of IGF-1 LR3 interactions.
Binding Kinetics and Receptor Occupancy
Radioligand binding studies utilizing [125I]-IGF-1 demonstrate that IGF-1 LR3 competes effectively for IGF-1 receptor binding sites. Competitive binding assays reveal Ki values in the low nanomolar range, indicating high receptor affinity. The modified structure exhibits reduced binding to IGF-binding proteins, resulting in increased free fraction availability for receptor interaction in serum-containing media.
Saturation binding experiments in myocyte cell models demonstrate saturable, high-affinity binding consistent with specific receptor-mediated interactions. Scatchard plot analysis reveals single binding site populations with dissociation constants typically below 5 nM.
Signalling Pathway Activation and Downstream Effects
IRS-1/PI3K/AKT Cascade
IGF-1 LR3 binding initiates rapid tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1), serving as a docking platform for phosphatidylinositol 3-kinase (PI3K) recruitment. PI3K activation generates phosphatidylinositol-3,4,5-trisphosphate (PIP3), which facilitates AKT serine/threonine kinase activation through PDK1-mediated phosphorylation.
Time-course studies demonstrate peak AKT phosphorylation at Ser473 and Thr308 residues occurring within 15-30 minutes following IGF-1 LR3 exposure in myocyte systems. This activation pattern exhibits dose-dependency, with maximal responses typically observed at concentrations exceeding 10 nM.
mTOR Pathway Engagement
Activated AKT phosphorylates multiple downstream targets, including mechanistic target of rapamycin (mTOR) complex 1. mTOR activation leads to phosphorylation of S6 kinase 1 (S6K1) and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1), key regulators of protein synthesis machinery.
Western blot analysis reveals concentration-dependent increases in phosphorylated S6K1 (Thr389) and 4E-BP1 (Thr37/46) following IGF-1 LR3 treatment in myocyte cell models. Peak phosphorylation typically occurs 1-2 hours post-treatment, with sustained activation observed for 4-6 hours.
Enzyme Kinetics and Cellular Assay Applications
Glucose Uptake Assays
IGF-1 LR3 demonstrates potent stimulation of glucose uptake in myocyte cell models through GLUT4 translocation mechanisms. Fluorescent glucose analog uptake assays reveal EC50 values ranging from 0.5-2 nM, indicating high potency for metabolic pathway activation.
The modified structure provides enhanced stability in glucose uptake assay conditions, maintaining biological activity for extended incubation periods compared to native IGF-1. This characteristic enables prolonged experimental protocols without frequent media supplementation.
Protein Synthesis Measurements
Cell-based protein synthesis assays utilizing radioactive amino acid incorporation demonstrate concentration-dependent responses to IGF-1 LR3 treatment. Maximum stimulation typically occurs at concentrations of 10-50 nM, with responses plateau beyond 100 nM, indicating receptor saturation.
Research Summary
IGF-1 LR3 represents a valuable research tool for investigating IGF-1 receptor pharmacology and associated signalling cascades in myocyte cell models. The compound exhibits high-affinity receptor binding with enhanced stability characteristics compared to native IGF-1. Comprehensive in vitro studies demonstrate potent activation of IRS-1/PI3K/AKT/mTOR pathways with well-characterized concentration-response relationships. These pharmacological properties make IGF-1 LR3 particularly suitable for enzyme kinetics studies, glucose uptake assays, and protein synthesis investigations in controlled laboratory environments.
All content is intended for in vitro laboratory research purposes only. Not for human or animal consumption. Not intended to diagnose, treat, cure, or prevent any condition.
Hexarelin
TB-500
Epithalon
Ipamorelin
Tirzepatide
CJC-1295 DAC
PT-141
Semaglutide
Selank
BPC-157
Sermorelin
Melanotan 2
IGF LR3
Tesamorelin
AICAR
IGF-DES
GHRP 2
Albuterol
Tamoxifen
Letrozole
Clomiphene
Tadalafil
Clenbuterol
Anastrozole
Finasteride
Exemestane
Sildenafil
Yohimbine
Bacteriostatic Water Recent Posts Melanotan 2 (MT2): Mechanism, Research, and Safety Considerations Ipamorelin: The Selective GHRP, Explained Tesamorelin: The GHRH Analog Studied for Visceral Fat Sermorelin: The Original GHRH Analog, Explained CJC-1295: How the GHRH Analog Works, and What Research Shows
Already a customer? Sign In
Create Account
All products on this site are for Research, Development use only. Products are Not for Human consumption of any kind. The statements made within this website have not been evaluated by the US Food and Drug Administration. The statements and the products of this company are not intended to diagnose, treat, cure or prevent any disease.
ElementSarms is a chemical supplier. ElementSarms is not a compounding pharmacy or chemical compounding facility as defined under 503A of the Federal Food, Drug, and Cosmetic act. ElementSarms is not an outsourcing facility as defined under 503B of the Federal Food, Drug, and Cosmetic act.
Sarms
Stacks
Research Liquids
Albuterol 5MG/ML | 30ML with dropper
Anastrozole 1.5MG/ML | 30ML with dropper
Clomiphene 50MG/ML | 30ML with dropper
Finasteride 5MG/ML | 30ML with dropper
Letrozole 3.5 MG/ML | 30ML with dropper
LiquiCia 30MG/ML | 30ML with dropper
LiquiCia T50 50MG/ML | 30ML with dropper
LiquiClen 200MCG/ML | 30ML with dropper
Liquistane / Exemestane 25MG/ML | 30ML with dropper
LiquiTamo 20MG/ML | 30ML with dropper
LiquiVia 25MG/ML | 30 ML with dropper
T3 LIOTHYRONINE 200MCG/ML | 30ML with dropper
Toremifene Citrate 60MG/ML | 30ML with dropper
Yohimbine HCL 10MG/ML | 30ML with dropper
Research Peptides
Aicar 50MG
BPC-157 + TB-500 Blend 2mg ea/ 4MG
BPC-157 5MG
CJC-1295 + DAC 2MG
CJC-1295 | No DAC 2MG
Epithalon 10MG
Frag Premium 176-191 5MG
GHK-CU Copper Peptide 50MG
GHRP-2 5MG
GHRP-6 5MG
Hexarelin 5MG
IGF-1 DES 1MG
IGF-1 LR3 1MG
Ipamorelin 5MG
Melanotan 2 10MG
NAD+ 500MG
PT-141 / Bremelanotide 10MG
GLP-1/GIP/GCG (RT)
Selank 5MG
GLP1 (SM)
Sermorelin 5MG
TB-500 5MG
GIP/GLP-1 (TZ)
PDE5 Inhibitors
GLP-1
Diluents
Bacteriostatic Water 10ML