IGF-1 LR3 1mg

IGF-1 LR3 is a synthetic peptide similar to human insulin-like growth factor 1 with enhanced bioavailability. IGF-1 LR3 is a longer peptide (L) and contains a substitution of arginine for glutamic acid at the third position in the peptide (R3). There is also an additional 13 amino acids added onto the N-terminal of the peptide, making it 83 total amino acids compared to only 70 amino acids in IGF-1.¹ These alterations enhance the half-life of IGF-1 LR3 to 20 to 30 hours, compared to 12 to 15 hours for IGF-1.² IGF-1 LR3 also has three times the potency of IGF-1.³ This increase in potency is driven by decreased binding of insulin-like growth factor binding proteins, which in turn increases the overall biological activity of the peptide.^1,2 IGF-1 is a peptide similar to insulin that binds to its receptor IGFR1 to promote cell growth, along with muscle fiber growth and differentiation.^4,5 IGF-1 LR3 is used both in in vitro and in vivostudies as an alternative to IGF-1, as it mimics the function and receptor binding efficiently. For example, one study looking at the effects of IGF-1 LR3 on fetal myocyte proliferation and heart mass in a sheep model found that the peptide stimulates the proliferation of cardiomyocytes while also increasing blood flow to the heart.⁶ Another study treated C2C12 cells in vitro and mice in an in vivo mouse tumor model with IGF-1 LR3 to demonstrate its role in blocking muscle wasting in cancer.⁵ IGF-1 LR3 activates the PI3K/AKT pathway and blocks the upregulation of muscle wasting factors, along with promoting protein synthesis.⁵

IGF-1 LR3 comes in a lyophilized white powder at a concentration of 1 mg/vial.

References: 1. Mohan S, Baylink DJ. IGF-binding proteins are multifunctional and act via IGF-dependent and -independent mechanisms. J Endocrinol. 2002 Oct;175(1):19-31. 2. Tomas FM, Knowles SE, Owens PC, Chandler CS, et al. Insulin-like growth factor-I (IGF-I) and especially IGF-I variants are anabolic in dexamethasone-treated rats. Biochem J. 1992 Feb;282(Pt 1):91-97. 3. von der Thusen J, Borensztajn KS, Moimas S, van Heiningen S, et al. IGF-1 Has Plaque-Stabilizing Effects in Atherosclerosis by Altering Vascular Smooth Muscle Cell Phenotype. Am J Pathol. 2011 Feb;178(2):924-934. 4. Wrigley S, Arafa D, Tropea D. Insulin-Like Growth Factor 1: At the Crossroads of Brain Development and Aging. Front Cell Neurosci. 2017 Feb;11:14. 5. Lovolger S, Wiemer EAC, van Vugt JLA, Huisman SA, et al. Inhibition of activin-like kinase ⅘ attenuates cancer cachexia associated muscle wasting. Sci Rep. 2019;9:9826. 6. Jonker SS, Giraud GD, Chang EI, Elman MR, Louey S. Coronary vascular growth matches IGF-1-stimulate cardiac growth in fetal sheep. FASEB J. 2020 Aug;34(8):10041-10055.