News On Japan

IGF-1 LR3: Muscle and Bone Research

Mar 02 (News On Japan) - Studies suggest that IGF-1 LR3 may be a significantly more potent derivative of native IGF-1 (insulin-like growth factor-1).

Research indicates it was designed to provide many of the same properties as IGF1 itself, including:

  • Enhanced muscle cell recovery and preservation
  • "Fat-burning" classification due to an increase in metabolic rate
  • Anti-aging action on cell cycles

In this informative guide, we include an IGF-1 LR3 overview and explore the various potential actions and effects that researchers may expect when evaluating IGF-1 LR3 in the lab. Ultimately, we reveal the top pick of an online vendor that sells pure IGF-1 LR3.

IGF-1 LR3 Peptide: What is it?

IGF-1 LR3 (insulin-like growth factor-1 long arginine 3) is a synthetically modified derivative of insulin-like growth factor-1, created in the liver in response to growth hormone endocrine stimulus.

More specifically, IGF-1 LR3 is an 83 amino acid analog of IGF-1 comprising the complete IGF-1 link with the substitution of an Arg (R) for the Glu(E) at position three and a 13 amino acid attachment peptide at the N terminus from methionyl porcine Growth Hormone. Research suggests that IGF-1 LR3 may be more potent than regular IGF-1 because of the decreased binding of Long R3 IGF-1 to IGF-binding proteins, allowing it to remain active up to 120 times longer than native IGF-1. This has been hypothesized to result in improved half-life and increased activity due to possible extended bioavailability. IGF-1 LR3 is thought to impair myostatin, thereby improving cell division and growth, enhancing fat metabolism, and facilitating muscle repair and hypertrophy. Clinically, IGF-1 and derivatives are evaluated in the context of muscle wasting due to conditions like HIV, as in cases of hormonal disorders.

IGF-1 LR3 Peptide Potential

Below, we present researchers with an overview of the theorized properties of IGF-1 LR3.

IGF-1 LR3 Peptide and Protein Synthesis

Investigations purport that IGF-1 LR3 may induce a high rate of cell proliferation (hyperplasia) and division due to remaining in the bloodstream for much longer than regular IGF-1, with the effect of increasing muscle cells. An additional consideration is that the IGF-3/IGF-1 ratio may be an important factor in determining the level of GH stimulation.

IGF-1 LR3 has also been speculated to act as a myostatin inhibitor, which might help prevent muscle breakdown and preserve contractile force in cases of muscle wasting. Investigations purport the peptide may activate a protein called MyoD, which stimulates muscle hypertrophy.

IGF-1 LR3 Peptide and Muscle

Findings imply that Insulin-like growth factor-1 (IGF-1) is particularly important for muscle regeneration. In a mouse model, direct presentations of recombinant IGF-1 at two, five, and seven days after injury appeared to have enhanced muscle healing in lacerated, contused, and strain-injured muscles. In addition, data from experimental studies also indicates that the direct presentation of recombinant growth factor proteins, including IGF-1, may improve muscle performance after a strain injury 15 days after injury.

The researchers also noted improvements in the injured muscle's tetanic and fast twitch strengths. Furthermore, IGF-1 was also indicated to significantly enhance the number and diameter of regenerating myofibers in the injured site. Age-related skeletal muscle mass wasting (sarcopenia) becomes an issue as regenerative ability declines.

IGF-1 LR3 Peptide and Blood Glucose

The two substances in the organism responsible for maintaining stable blood sugar levels are insulin and IGF-1. Studies have purported that insulin-like growth factor-1 may cause blood sugar levels to lower and improve insulin sensitivity and blood lipids in type 2 diabetic research models. These effects of IGF-1 LR3 are believed to ultimately reduce insulin requirement by up to 10% to maintain blood sugar levels.

IGF-1 LR3 Peptide and Bone

Data from clinical trials indicates that IGF-1 LR3 may stimulate bone formation via a direct effect on osteoblasts and may have significant anabolic activity and bone protective effects. Researchers have linked higher IGF-1 levels to greater bone mineral density in older female subjects. In addition, researchers noted that GH and IGF-1 may increase bone mineral density (BMD) and help optimize peak bone acquisition while reducing the risk of fracture due to GH deficiency.

Research indicates that growth hormone and IGF-1 may also be fundamental in skeletal growth, given that IGF-1 might cause increased uptake of amino acids and nutrients, particularly collagen. IGF-1 is believed to be crucial to development, with research suggesting that high levels of serum IGF-1 might directly correlate to higher bone mineral acquisition later in life.

Click here to be redirected to the Core Peptides website for more informative and educational articles about peptides. Please note that none of the substances mentioned in this article have been approved for human consumption and should, therefore, not be used by unlicensed individuals outside of contained laboratory environments.


[i] Tomas, F. M., Lemmey, A. B., Read, L. C., & Ballard, F. J. (1996). Superior potency of infused IGF-I analogues which bind poorly to IGF-binding proteins is maintained when administered by injection, Journal of Endocrinology, 150(1), 77-84. Retrieved Jul 7, 2022, from

[ii] Laron Z. The essential role of IGF-I: lessons from the long-term study and treatment of children and adults with Laron syndrome. J Clin Endocrinol Metab. 1999;84(12):4397-4404. doi:10.1210/jcem.84.12.6255

[iii] Lambrecht N. IGF-1/IGFBP-3 Serum Ratio as a Robust Measure to Determine GH Deficiency and Guide Human Recombinant GH Therapy. J Clin Endocrinol Metab. 2023 Mar 10;108(4):e54-e55. doi: 10.1210/clinem/dgac687. PMID: 36454697.

[iv] Li N, Yang Q, Walker RG, Thompson TB, Du M, Rodgers BD. Myostatin Attenuation In Vivo Reduces Adiposity, but Activates Adipogenesis. Endocrinology. 2016;157(1):282-291. doi:10.1210/en.2015-1546

[v] Engert JC, Berglund EB, Rosenthal N. Proliferation precedes differentiation in IGF-I-stimulated myogenesis. J Cell Biol. 1996;135(2):431-440.

[vi] Schiaffino S, Mammucari C. Regulation of skeletal muscle growth by the IGF1-Akt/PKB pathway: insights from genetic models. Skelet Muscle. 2011;1(1):4. Published 2011 Jan 24. doi:10.1186/2044-5040-1-4

[vii] Laumonier, Thomas & Menetrey, Jacques. (2016). Muscle injuries and strategies for improving their repair. Journal of Experimental Orthopaedics. 3. 10.1186/s40634-016-0051-7.

[viii] Kasemkijwattana C, Menetrey J, Bosch P, Somogyi G, Moreland MS, Fu FH, Buranapanitkit B, Watkins SS, Huard J. Use of growth factors to improve muscle healing after strain injury. Clin Orthop. 2000;370:272–285.


Makoto Nishimoto, a former Miyazaki City councilor who goes by the name Super Crazy Kun, has been sentenced to four years and six months in prison for forcibly taking a woman in her 30s, whom he knew, into a hotel in Miyazaki City last September and assaulted her by restraining her arms and committing non-consensual intercourse resulting in injury.

NTT has unveiled Japan's first technology aimed at improving the power efficiency of data centers, which are known for their high heat generation and substantial power consumption.

A pair of premium melons from Yubari City in northern Japan has fetched 3 million yen in the first auction of the year. That's about 19,000 dollars. The luxury fruit is a popular gift in the country. (NHK)

A new facial recognition system, set to be widely used at next year's Osaka-Kansai Expo, has been unveiled.

Shohei Ohtani has reportedly purchased a mansion worth approximately 1.2 billion yen near Dodger Stadium, according to local media.



JR Central has announced that it will commence full-scale tunnel excavation for a section of the Linear Chuo Shinkansen in Kanagawa Prefecture starting on the 27th. This marks the first time a tunnel will be fully excavated at great depth between Tokyo and Nagoya.

A new facial recognition system, set to be widely used at next year's Osaka-Kansai Expo, has been unveiled.

Professor Kenjiro Kimura of Kobe University, who also serves as the CEO of Integral Geometry Science, has made a groundbreaking discovery in applied mathematics by solving an unsolved problem and inventing the world's first 'through-object visualization technology.'

Tokyo-based startup Innovative Space Carrier Inc. will develop a reusable satellite launch rocket in partnership with a U.S rocket engine maker, aiming for commercial use by around 2030. (Kyodo)

A next-generation vertical take-off and landing aircraft took to the skies of Tokyo for the first time on Friday. (NHK)

An event allowing visitors to experience life in 2050 has launched in Tokyo, including an elevator which enables transportation to space via a cable extending from a satellite to Earth.

The supercomputer 'Fugaku' has achieved the world’s top ranking in two categories for the ninth consecutive term.

A potentially new bee species has been identified by staff at the Tochigi Prefectural Museum, sparking a call for more specimens on social media after initially collecting only six.