Different Effects of Insulin-Like Growth Factor-1 and Insulin-Like Growth Factor-2 on Myogenic Differentiation of Human Mesenchymal Stem Cells

Figure 1

IGF-1 and IGF-2 supplementation differently affected levels of pluripotency-associated and muscle differentiation markers in PMSC. (a) IGF-1 treatment had no effect on OCT4 levels, while IGF-2 treatment increased OCT4 levels at 3, 7, and 14 days compared to muscle differentiation alone. (b) SOX2 and (c) Nanog levels were decreased after IGF-1 treatment at early time points only, whereas IGF-2 treatment decreased SOX2 levels until day 7 and at all time points for Nanog. (d) Pax3/7 levels were increased at 7 and 14 days and did not decrease after IGF-1 treatment, while IGF-2 treatment increased Pax3/7 levels at all time points but decreasing with time. (e) MyoD, (f) MyoG, and (g) MHC protein levels did not change with IGF-1 supplementation, except for a decrease in MyoD levels at day 14. In contrast, IGF-2 treatment increased muscle differentiation marker levels at all time points. Protein levels were quantified by densitometry and normalized to β-actin. Data is presented as the mean ± SEM of 3 independent experiments. Two-way ANOVA with Bonferroni’s multiple comparison test was performed to determine , , and comparing control to muscle differentiation conditions, or ^### comparing the same treatment over time.

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