MGF vs. PEG-MGF: Variants for Muscle Regeneration

by | Oct 5, 2021 | Research

The mechanical growth factor has a tremendous socio-economic impact on the diseases of the aging population. Its functions still require a lot of research. This small peptide shows adequate tissue penetration and can be manufactured cheaply and modified into PegylatedMechano Growth Factor, increasing its stability. They are good candidates for developing excellent diagnostic and therapeutic methods.


MGF (Mechano Growth Factor)

Mechanical growth factor (MGF) is a synthetically produced peptide that is an alternative splicing variant of insulin-like growth factor 1 (IGF – 1). First described in skeletal muscles, it serves as a local tissue repair factor that responds to changes in physiological conditions or environmental stimuli that induce muscle cell proliferation. It activates satellite cells in muscle and increases the number of desmin positive myogenic precursor cells, leading to hypertrophy or regeneration. It acts as a neuroprotective agent in cerebral ischemia.
MGF is characterized as IGF – 1Eb with a 52 base pair insert in rats but as IGF – 1Ec with a 49 base pair insert within the E domain of exon 5 in humans. It has a relatively short half-life of only a few minutes, which is why PEG-MGF was developed to compensate for this particular disadvantage.


PEG-MGF, known as Pegylated Mechano Growth Factor, is a variant of IGF – 1. PEGylation modifies MGF by fusing polyethylene glycol (PEG) into it, extending its half-life from a few minutes to days and allowing it to travel through the bloodstream for a long time before it is broken down and excreted by the kidneys. This process is important for animal muscle regeneration after physical exertion or injury by promoting nitrogen retention and increasing protein synthesis.


Several animal studies have shown that PEG-MGF supports the regeneration process of muscle, positively regulates protein synthesis, and activates satellite cells. PEG-MGF is a potent inducer of muscle hypertrophy in experiments after the PEG-MGF cDNA has been inserted into a plasmid vector and introduced by intramuscular injection. Its addition to muscle myoblasts increased proliferation and delayed differentiation even in the presence of anti – IGF 1 receptor antibodies, possibly by activating fibrinolysis of matrix and metalloproteinase systems. In addition, intense exercise stimulates the release of growth hormone in the muscles to release MGF since levels of this hormone decrease as animals age.
Furthermore, a recent study of PEG-MGF showed that the activity of protein kinase C is necessary for the activation of this peptide (translocation to the nucleus) of factor 2 related to NFE 2 (Nrf2). This, in turn increases the expression of heme oxygenase 1, a critical event in the mediation of neuroprotection of neurons from oxidative stress-induced apoptosis in the brain.


In addition to muscle, PEG-MGF has been suggested to have other effects in the body of animal subjects.
– PEG-MGF has been shown to enhance the proliferation and migration of bone marrow-derived mesenchymal
stem cells, which are a source of autologous stem cells for transplantation to the heart.
There is a transient regulation of PEG b MGF expression in response to myocardial infarction associated with ischemia in the heart. Its expression is induced in one hour and remains elevated for up to 8 weeks. Intracoronary administration of this peptide induces myocardial protection and improves hemodynamic function more than mature IGF – 1 after myocardial infarction in sheep. The cellular protection conferred by PEG-MGF was based on the inhibition of apoptosis in the border area of the infarct.
– PEG-MGF has been shown to stimulate proangiogenic activities in human vascular endothelial cells. Therefore, it could confer potentially beneficial therapeutic effects at the level of vascular regeneration and collateralization to restore blood flow to the heart after myocardial infarction.
– IGF – 1 plays an essential role in the interface between neurons in injured or damaged muscles. In ALS, that is, amyotrophic lateral sclerosis (a disease with loss of motor neurons and progressive muscle weakness), muscle overexpression of IGF – 1 slowed the progression of the disease. Treatment with PEG-MGF produced improvements. More motor neurons survived in PEG MGF-treated mice.
– MGF is expressed in excess in regenerating regions after global cerebral ischemia in adults. Its transcripts, which are expressed during brain development, show particular time distributions. Furthermore, neonatal hypoxia and insults of hypoxic ischemia lead to increased and prolonged expression of only the MGF isoform.


Disclaimer: The products mentioned are not for human or animal consumption. All the information shared in this article is for educational purposes only.