Fig. 2

TNF-α-induced apoptosis in primary rat myoblasts. a Western blot showing the activation/cleavage of caspase 7 and PARP in myoblasts exposed to different concentrations of TNF-α (5–20 ng/ml). b The cleavage of PARP at different time-points (0–48 h). c The effects of a pan-caspase inhibitor (Z-VAD-FMK) on the cleavage of PARP. d, e Caspase 3/7 activity (d) and caspase 8 activity (e) in myoblasts after treatment with 10 ng/ml TNF-α for up to 24 h. f The percentage of Annexin V-positive cells (early apoptotic cells) after treatment with 10 ng/ml TNF-α for up to 24 h. Data is from flow cytometry experiments. n = 3. g The percentage of TUNEL-positive cells (late apoptotic cells) after treatment with 10 ng/ml TNF-α for up to 48 h. n = 6. h TUNEL labeling time course up to 48 h. DAPI staining shown in the upper left corner. × 20 magnification. Statistical significance was calculated using one-way ANOVA with post hoc test (Bonferroni correction). **P < 0.01, and ***P < 0.001. ns = not significant