Figure 5
From: IGF-1 Expression in Infarcted Myocardium and MGF E Peptide Actions in Rat Cardiomyocytes in Vitro
Analysis of H9C2 cell proliferation using the trypan blue assay. Panel I: The effects of mature IGF-1 and synthetic MGF E peptide on H2C2 cell proliferation (% cell number changes) in a dose-dependent manner as presented in the “Materials and Methods” section. Note that the IGF-1R neutralizing antibody (anti-IGF-1R ab) blocked IGF-1 effects without affecting the action of synthetic MGF E peptide on H9C2 cell proliferation. Data are presented as mean ± SEM. *Significantly different (P< 0.001) from control conditions. Panel II: Representative Western blot analysis of ERK1/2 and Akt phosphorylation in H9C2 cells after stimulation with IGF-1 and synthetic MGF E peptide in a time-dependent manner. Note that the MGF E peptide activated ERK1/2 phosphorylation; however, it did not activate Akt phosphorylation. IGF-1 did activate both ERK1/2 and Akt in H9C2 myocar-dial-like cells as expected. These data suggest that synthetic MGF E peptide could signal via an IGF-1R-independent mechanism in H9C2 cells.