MGF 2mg (Euro-Pharmacies, Europe)

MGF is derived from the IGF-I gene through alternative splicing and possesses distinct 3' exons compared to the liver or systemic type (IGF-IEa). In humans, it features a 49 base pair insert, while rodents have a 52 base pair insert within the E domain of exon 5. This insertion leads to a shift in the reading frame, resulting in a different carboxy-terminal sequence than that of systemic IGF-IEa. MGF, along with other IGF isoforms, shares the same 5' exons that encode the ligand-binding domain of IGF-I. The processing of its pro-peptide yields a mature peptide that plays a role in enhancing protein synthesis. Additionally, there is evidence indicating that the carboxy-terminal portion of the MGF peptide functions as a distinct growth factor. This promotes the proliferation of mononucleated myoblasts or satellite (stem) cells, thus increasing their availability for local repair.

MGF exhibits a dual function, similar to other IGF-I isoforms, by promoting protein synthesis while simultaneously activating satellite cells. However, the latter function of MGF may hold greater significance, as most of the mature IGF-I will originate from IGF-IEa during the secondary phase of repair. Nonetheless, MGF has been demonstrated to be a powerful inducer of muscle hypertrophy in studies where the cDNA of MGF was inserted into a plasmid vector and delivered through intramuscular injection. This approach led to a 20% increase in the muscle weight at the injection site within two weeks, with analyses revealing that this growth resulted from an increase in muscle fiber size. Other research groups have conducted similar experiments using a viral construct containing the liver type of IGF-I, which resulted in a 25% increase in muscle mass, but this process took over four months to manifest (Musaro et al. 2001). Therefore, MGF's dual role in stimulating satellite cell activation and promoting protein synthesis indicates that it is significantly more effective than the liver type or IGF-IEa for inducing rapid hypertrophy.

The peptide is typically taken in doses ranging from 200-400 mcg daily and interacts favorably with other substances such as IGF and PEG.