IGF-1 LR3 is a synthetic variant of the naturally occurring insulin-like growth factor 1 (IGF-1), which plays a significant role in human growth and development throughout life. IGF-1 is a primary mediator of the effects of growth hormone (GH), promoting cellular growth, proliferation, and survival across various types of tissues. The "LR3" in IGF-1 LR3 stands for "Long Arginine 3," indicating that the molecule has been modified with the addition of an arginine at the third position and an extension of the peptide sequence at the N-terminus, which results in a longer half-life compared to endogenous IGF-1.
The modifications made to create IGF-1 LR3 significantly enhance its potency and efficacy, primarily due to its reduced affinity for IGF-1 binding proteins. These binding proteins normally inhibit the biological activities of IGF-1 by binding to it and preventing its interaction with the IGF-1 receptor. The alterations in IGF-1 LR3 reduce its binding to these proteins, thus increasing its availability and activity in the body. The key features and implications of IGF-1 LR3 include:
However, the use of IGF-1 LR3 carries potential risks and side effects, much like any powerful growth factor. These can include hypoglycemia (due to its insulin-like effects), possible increased risk of certain cancers (due to its cell proliferation-promoting activities), and acromegaly-like symptoms with long-term overuse. The legality and ethical considerations surrounding the use of IGF-1 LR3, especially in competitive sports, make it a controversial substance, regulated under specific conditions.
Given its powerful biological effects, the administration of IGF-1 LR3 should be approached with caution and under the guidance of a healthcare professional, ensuring that its use is aligned with medical advice and ethical standards.