Internalization of IGF-I into Skeletal Muscle Cells

Background: IGF-I is a growth factor with known developmental and growth modulating functions on skeletal muscles. E-peptides, either EA or EB peptides, are the C terminal part of the IGF-I growth factor. AIM: To compare the differences between EA and EB internalization of IGF-I into skeletal muscle cells. Method: C2C12 muscle cells were starved overnight in serum free medium, and then treated with either IGF-I alone or IGF-I and either EA or EB synthetic peptides. The final group received no treatment, and acted as a negative control. A pilot immunofluorescence staining experiment was performed to compare IGF-I internalization in C2C12 cells. Results: The results showed more internalization of IGF-I into cells when they were treated with EA peptide compared to treatment with EB or no treatment. Conclusion: E-peptide had an effect on internalization of IGF-I into C2C12 muscle cells, and more signals were seen with EA peptide treatment, which was expressed as a change in function.