Fig. 3

Effect of optimal H₂O₂ on the mitochondria-mediated apoptosis pathway in BMSCs. Western blot analysis of the expressions of Bcl-2, Bax, and caspase-3 proteins in BMSCs exposed to various low concentrations of H₂O₂ (25, 50, and 100 μM) for 12 h. a The bar graphs showed the ratio of Bax/Bcl-2 and the quantification of the caspase-3 protein in BMSCs. b Western blot analysis of the expressions of Bcl-2, Bax, and caspase-3 in BMSCs exposed to 50 μM H₂O₂ for different time intervals (3, 6, 12, 24, and 36 h). The bar graphs showed the ratio of Bax/Bcl-2 and the quantification of the caspase-3 protein; Western blot analysis of the expressions of Bcl-2, Bax, caspase-9/3, and cleaved caspase-9/3 in MSCs exposed to 300 μM H₂O₂ for 24 h after pretreatment with 50 μM H₂O₂ for 12 h. c The bar graphs showed the ratio of Bax/Bcl-2 in BMSCs. d The bar graphs showed the quantification of the caspase-9 and cleaved caspase-9 protein. e The bar graphs showed the quantification of the caspase-3 and cleaved caspase-3 protein. All results are presented as mean ± SEM (n = 3). *P < 0.05, **P < 0.01 vs. the control group; ^##P < 0.01 vs. the 300 μM H₂O₂ group