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IGF-1 LR3 Peptide Overview for 2024

IGF-1 LR3 Peptide Overview for 2024

Insulin-like growth factor-1 Long R3, more commonly referred to by its acronym IGF1 LR3, consists of an 83 amino acid chain without glycosylation. At position 3, arginine (R or arg) was modified with glutamic acid (E or Glu), producing IGF1 LR3. This modified form contains all of its native amino acid sequence, with two notable modifications; firstly, its N-terminus was lengthened with thirteen amino acid peptide and called long; and secondly, all its native sequence was still present with these modifications in place. Polypeptide native forms consist of its conformational shape and sequence of amino acids found naturally. As measured by mass spectrometry, IGF1 LR3 has a molecular weight of 9.116 daltons. Escherichia coli can produce IGF1 LR3 through the help of an engineered protein expression system that uses proprietary technology. Next, purification and folding procedures ensure an efficient IGF1 LR3 protein that can bind directly with its receptor on insulin-like growth factor-1 receptor. This results in highly active yet functional IGF1 LR3, capable of binding insulin-like growth factor-1 receptor.

What Is IGF-1 LR3 Peptide Used For?

Studies suggest the IGF-1 gene encodes for an endocrine peptide hormone IGF-1 produced in liver tissue. Its production may be stimulated by growth hormone (GH). IGF-1’s protein sequence contains three disulfide bridges similar to insulin’s, providing potential stimulation of protein synthesis; additionally it employs paracrine and autocrine signaling pathways to communicate its influence to targeted tissues.

Insulin-like growth factor 1 (IGF-1) appears to enhance cellular insulin sensitivity. It has been speculated to speed up fat catabolism, a destructive metabolic pathway that breaks down fat into simpler compounds while releasing energy to power cellular processes. Additionally, findings imply it may increase protein synthesis in individual myocytes, conserve glucose, and stimulate fat metabolism in muscle tissue; overall, muscular hypertrophy is defined as an expansion caused by a rise in cell size. There is convincing data suggesting that IGF-1 may lower body fat percentages.

Several cell types include the IGF-1R receptor, which investigations purport may mediate the effects of IGF-1. According to molecular research, IGF-1R is a member of the tyrosine-kinase receptor family. IGF-1R seems to inhibit apoptosis and stimulate cell growth and proliferation by activating the intracellular AKT signaling pathway upon ligand interaction. Hence, IGF-1 appears to promote systemic growth by enhancing cell proliferation, differentiation, and growth.

New research indicates that IGF-1 may act as a mediator between growth hormone and its targets. The results suggest that IGF-1 might act on most cells. During reproductive development, the organism typically produces the most IGF-1, the hormone that causes a growth spurt and the development of new muscles. Hence, an absence of growth hormone or a shorter stature might be the result of IGF-1-induced inhibited development. Multiple studies in animal research models have suggested promise in the context of using recombinant hman growth hormone (GH) or insulin-like growth factor-1 (IGF-1 DES) to promote growth in research models lacking these hormones.

Additionally, studies have indicated that IGF-1 may control neuronal nucleotide synthesis and neuronal growth and development. According to therapeutic research, motor axon degeneration and other peripheral neuropathies may be managed with recombinant IGF-1.

According to studies, the functional biologic profile of IGF1 LR3 seems identical to that of endogenous IGF-1. The upregulation of glucose and amino acid migration into cells by IGF1 LR3 has also been speculated. Investigations purport that cellular protein content may be increased due to IGF1 LR3’s potential on RNA and protein synthesis, offset by its inhibitory effect on protein breakdown. 

IGF1 LR3 Peptide and Metabolism

The primary objective of this research was to examine the role of IGF1 LR3 in protein metabolism. Beef heifers that were purposefully underfed to induce weight loss were the research models of this experiment. The subjects were split into two groups: one to take the exam and another to serve as a control. The results suggested that the experimental group of heifers may have successfully preserved protein throughout their bodies, including skeletal muscle.

IGF-1 LR3 Peptide and Atherosclerotic Plaques 

An article titled “IGF-1 has plaque-stabilizing potential in atherosclerosis by modifying vascular smooth muscle cell phenotype” was published in 2011 by von der Thüsen et al. This research examined the potential impact of IGF1 and IGF1 LR3 on atherosclerotic plaques. This animal model research examined the effects of atherosclerotic plaque inflammation on IGF-1 signaling pathway functional stability and of IGF-1 supplementation (using recombinant analogs) on plaque phenotype. The findings implied that IGF-1 signaling pathways might be inhibited by an M1-polarized medium that macrophages have conditioned. The pathways that led to the inhibition were as follows:

  • IGF1 ablation
  • Increased expression of IGF-binding protein-3
  • An uptick in vascular smooth muscle cell apoptosis with a reduction in degradation

The medium seemed to suppress both the col3a1 and α-actin genes. Nevertheless, the medium included an excess of the matrix-degrading enzymes.

The findings also suggested that IGF1 LR3 might fix all the previously described issues, as all the quantifiable plaque parameters in freshly discovered atherosclerotic plaques decreased with time.

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[i] Lu Z, Liu N, Huang H, Wang Y, Tu T, Qin X, Wang X, Zhang J, Su X, Tian J, Bai Y, Luo H, Yao B, Zhang H. Recombinant expression of IGF-1 and LR3 IGF-1 fused with xylanase in Pichia pastoris. Appl Microbiol Biotechnol. 2023 Jul;107(14):4543-4551. doi: 10.1007/s00253-023-12606-0. Epub 2023 Jun 1. PMID: 37261455.

[ii] Stremming J, White A, Donthi A, Batt DG, Hetrick B, Chang EI, Wesolowski SR, Seefeldt MB, McCurdy CE, Rozance PJ, Brown LD. Sheep recombinant IGF-1 promotes organ-specific growth in fetal sheep. Front Physiol. 2022 Aug 25;13:954948. doi: 10.3389/fphys.2022.954948. PMID: 36091374; PMCID: PMC9452821.

[iii] White A, Stremming J, Brown LD, Rozance PJ. Attenuated glucose-stimulated insulin secretion during an acute IGF-1 LR3 infusion into fetal sheep does not persist in isolated islets. J Dev Orig Health Dis. 2023 Jun;14(3):353-361. doi: 10.1017/S2040174423000090. Epub 2023 Apr 28. PMID: 37114757; PMCID: PMC10205682.

[iv] Salvi R, Kumar C, Brahmbhatt K, Subedi R, Idicula-Thomas S, Madan T, Biswas B. N-Linked Glycosylation in Chinese Hamster Ovary Cells Is Critical for Insulin-like Growth Factor 1 Signaling. Int J Mol Sci. 2022 Nov 29;23(23):14952. doi: 10.3390/ijms232314952. PMID: 36499281; PMCID: PMC9735751.

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