Figure 2. Expression changes in ODC and SSAT and effect of SPD in H2O2- treated cardiomyocytes. (A) Western blot analysis of ODC and SSAT expression in NRCMs treated with or without 40 μM H2O2. GAPDH was used as loading control (n = 4). (B, C) Concentration- and time-dependent effect of SPD on the viability of NRCMs treated with 40 μM H2O2 (n = 8). (D) SA-β-gal staining in NRCMs (top) and H9C2 cells (bottom). The positive area of SA-β-gal staining is shown in the right-hand graph (n = 8). Scale bars: 20 μm. (E) Representative immunoblot bands for p21 and p16, and quantification of protein levels in NRCMs (n = 4). # P < 0.05 vs. control, ## P < 0.01 vs. control, * P < 0.05 vs. H2O2, ** P < 0.01 vs. H2O2.