Fig. 1

Optimization of H₂O₂ concentrations for preconditioning BMSCs. a BMSCs were treated with the indicated concentrations of H₂O₂ (0–200 μM) for 12 h. The cell viability was measured by ATP assay. Values represent the mean ± standard errors of the means (SEM) (n = 3). b The effect of H₂O₂ on BMSC proliferation determined by the CCK-8 assay. H₂O₂ at 25 and 50 μM significantly promoted the proliferation of BMSCs compared with the control (n = 3). c Western blot analysis of cyclin D1 and p16 expressions in BMSCs exposed to different low concentrations H₂O₂ for 12 h. Values represent the mean ± SEM (n = 3). *P < 0.05, **P < 0.01 vs. 0 μM H₂O₂. d Representative images of the scratch assay showed the migration of BMSCs with or without 50 μM of H₂O₂ treatment for 12 h and 24 h. Scale bar, 100 μm. e Quantification of the number of cells which have migrated into the scratch zone; 50 μM of H₂O₂-treated cells had a significantly increased migration compared with control untreated cells (n = 3). f Images of transmigrated BMSCs (stained with crystal violet) are shown (× 200 magnification). Scale bar, 100 μm. g Quantitative analysis of migrated cells. Data is presented as mean ± SEM of the six independent experiments (n = 6). h Western blot analysis of SDF-1 and CXCR4 expressions in BMSCs exposed to different low doses of H₂O₂ for 12 h. Values represent the mean ± SEM (n = 3). *P < 0.05, **P < 0.01 vs. the control group (0 μM H₂O₂); ^#P < 0.05 vs. the 50 μM H₂O₂ group