MGF E-domain cell response
Synthetic peptides derived from the E-domain of the IGF-1Ec splice variant have been investigated for effects on progenitor-cell proliferation, survival, migration and differentiation.
Biological pathway
Synthetic MGF E-domain peptide exposure → incompletely defined receptor or membrane interaction → context-dependent changes in progenitor-cell proliferation, survival and differentiation.
Evidence summary
Some cell and animal studies report biological activity, but other laboratories have failed to reproduce key muscle-cell findings and the endogenous existence of a freely circulating MGF E-peptide remains disputed.
Limitations
The receptor is not established, peptide identity varies between studies and vendor products, and laboratory effects do not establish human muscle recovery or hypertrophy.