IGF-1 LR3 (Long R3)

IGF1-LR3 Overview

IGF1-LR3 (Insulin-like Growth Factor-1 Long Arginine 3) represents the pinnacle of peptide engineering regarding the IGF-1 signaling pathway. Standard IGF-1 is often restricted in its research application due to its rapid degradation and high affinity for IGF-binding proteins (IGFBPs), which effectively neutralize the peptide before it can reach its target receptors. IGF1-LR3 was developed specifically to overcome these biological hurdles.

By modifying the molecular sequence, scientists created a version of IGF-1 that possesses a significantly reduced affinity for these inhibitory proteins. This results in a higher concentration of the free peptide circulating in the bloodstream, leading to a biological half-life that is approximately 120 times longer than that of native IGF-1. This extended window of activity allows for more sustained and profound observation of cellular proliferation and systemic growth processes in laboratory models.

IGF1-LR3 Structure

The structural integrity and increased potency of IGF1-LR3 are derived from two distinct alterations. First, a 13-amino acid extension is integrated into the N-terminal end of the molecule. Second, the glutamic acid residue found at the third position of the original IGF-1 sequence is replaced with an arginine residue. This specific configuration changes the molecular charge and shape, preventing binding proteins from latching onto the peptide.

Structure Solution Formula: C396H606N112O121S6

Product Profile Table

Component

Technical Specification

Peptide Type

Growth Factor Analog

Amino Acid Count

83 Amino Acids

Molecular Weight

9111.6 Daltons

Physical Appearance

White Lyophilized Powder

Purity

Greater than 98 percent

Biological Activity

Potent IGF-1 Receptor Agonist

IGF1-LR3 Research

Cellular Proliferation and Differentiation

In research settings, IGF1-LR3 acts as a powerful catalyst for cell division (mitosis). While its primary focus is often seen in musculoskeletal tissues, it exerts a systemic influence, promoting growth in the liver, kidneys, skin, and lungs. It is classified as a maturation hormone because it facilitates differentiation—the process by which generic cells become specialized units capable of performing complex biological functions.

Crucially, IGF1-LR3 is known for inducing hyperplasia rather than simple hypertrophy. While hypertrophy increases the size of existing cells, hyperplasia results in the creation of new cells. This is a vital distinction in the study of muscle regeneration and tissue repair, as it suggests the potential for a fundamental increase in tissue density and functional capacity.

Glucose Regulation and Lipid Metabolism

IGF1-LR3 demonstrates a unique ability to influence metabolism through its interaction with both the IGF-1 and insulin receptors. This dual-action mechanism enhances the uptake of glucose into muscle and liver cells, effectively lowering blood sugar levels. In response to this glucose clearance, the body naturally shifts its energy consumption toward adipose (fat) stores.

In studies involving diabetic murine models, the administration of IGF1-LR3 has been observed to decrease the requirement for exogenous insulin by roughly 10 percent. This makes it a critical subject in research aimed at reversing insulin resistance and understanding the early-stage prevention of Type 2 diabetes.

Research into Aging and Longevity

The GH/IGF axis is one of the most studied pathways in longevity science. IGF1-LR3 is utilized to examine how sustained growth signaling can repair damaged cells and protect against age-related decline. Ongoing research explores whether the peptide can slow the progression of chronic conditions such as dementia and sarcopenia by maintaining a higher rate of cellular turnover and systemic repair than what is naturally seen in aging populations.

Counteracting Myostatin

Myostatin is a protein that acts as a growth inhibitor, preventing muscles from exceeding a certain size. IGF1-LR3 has the capacity to impair myostatin signaling. By activating a protein called MyoD, IGF1-LR3 encourages muscle hypertrophy and repair even in environments where myostatin would normally prevent growth. This research is particularly promising for studying conditions like muscular dystrophy and prolonged muscle atrophy due to immobility.

Glucocorticoid Protection

Glucocorticoids are frequently used to treat inflammation but often result in the side effect of bone and muscle wasting. IGF1-LR3 is being studied for its ability to offset these catabolic effects. Researchers are looking into whether co-administration can preserve bone density and muscle mass during long-term steroid therapy, potentially allowing for more aggressive treatment of inflammatory diseases without the associated physical deterioration.

Article Author

The referenced literature underwent research, compilation, and organization by Dr. E. Logan, M.D. Dr. E. Logan possesses a doctorate qualification from Case Western Reserve University School of Medicine alongside a B.S. in molecular biology.

Scientific Journal Author

Dr. Anastasios Philippou, Ph.D. focused on Experimental Physiology at the National and Kapodistrian University of Athens Medical School. He is now a National Center Manager and Assistant Professor. His research pertains to muscle regeneration, the role of IGF-1 in skeletal muscle physiology, and the expression of IGF-1 isoforms after exercise.

Dr. Anastasios Philippou, Ph.D. is referenced as a leading scientist in the development of IGF1-LR3. This is not an endorsement of the product. There is no affiliation between Peptide Sciences and this doctor. The purpose of citing this doctor is to recognize the exhaustive research conducted by scientists studying this peptide. Dr. Anastasios Philippou, Ph.D. is listed in citations 7 and 8.

Referenced Citations

1. Adipose Tissue-Derived Stem Cell Secreted IGF-1 Protects Myoblasts from the Negative Effect of Myostatin. Available: [suspicious link removed].
2. N. Li, Q. Yang, R. G. Walker, T. B. Thompson, M. Du, and S. O. Rodgers, Myostatin Attenuation In Vivo Reduces Adiposity, but Activates Adipogenesis, Endocrinology, vol. 157, no. 1, pp. 282–291, Jan. 2016.123
3. E. Corpas, S. M. Harman, and M. R. Blackman, Human growth hormone and human aging, Endocr. Rev., vol. 14, no. 1, pp. 20–39, Feb. 1993.456
4. W. E. Son7ntag, A. Csiszar, R. deCabo, L. Ferrucci, and Z. Ungvari, Diverse roles of growth8 hormone and insulin-like growth factor-1 9in mammalian aging: progress and controversies, J. Gerontol. A. Biol. Sci. Med. Sci., vol. 67, no. 6, pp. 587–598, Jun. 2012.
5. IGF hGH/IGF system: metabolism outline and physical exercise. PubMed - NCBI. Available: https://www.ncbi.nlm.nih.gov/pubmed/22714057.
6. B. Y. Hanaoka, C. A. Petersen, C. Horbinski, and L. J. Crofford, Implications of glucocorticoid therapy in idiopathic inflammatory myopathies, Nat. Rev. Rheumatol., vol. 8, no. 8, pp. 448–457, Aug. 2012.
7. A Philippou, A Halapas, M Maridaki, M Koutsilieris. Musculskeletal Neuronal Interact, 2007.
8. A Philippou, E Papageorgiou, G Bogdanis, A Halapas. In vivo, 2009.

Storage

IGF1-LR3 exhibits minimal to moderate side effects and excellent bioavailability in laboratory mice. Dosage in mice does not scale directly to humans. This product is for scientific research only.

Lyophilized IGF1-LR3 should be stored at negative 20 degrees Celsius. After reconstitution, it should be kept between 2 and 8 degrees Celsius. Avoid repeated freeze-thaw cycles and keep away from direct light to maintain peptide stability.