Adaptive protection against damage of preconditioning human umbilical cord-derived mesenchymal stem cells with hydrogen peroxide.

Adaptive protection against damage to human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) was investigated by preconditioning with low-concentration hydrogen peroxide (H2O2) for a short-time period. Separation, culture, amplification, purification, and identification of immunophenotype and growth curve measurements of hUC-MSCs were performed in vitro. At the logarithmic phase, hUC-MSCs were incubated with different (H2O2) concentrations for 1 and 12 h, and the effects were detected by a cell metabolism assay. Then, hUC-MSCs were preconditioned with 10, 20, 50, and 100 mM (H2O2) for 1 h, restored for 0, 12, and 24 h, and then damaged with 700, 800, and 900 mM (H2O2) for 12 h. Cell morphology, cell metabolism, and the number of cells were measured to determine the protective role of preconditioning. Flow cytometry analysis revealed that the cells expressed CD29 and CD44, but not CD34 and CD45. The growth curve showed that hUC-MSCs reached the logarithmic phase in 3-6 days. The cell metabolism assay showed that (H2O2) induced hUC-MSCs damage in a dose- and time-dependent manner. The cell morphology, cell metabolism, and number of cells all showed that preconditioning with 10, 20, 50, and 100 mM (H2O2) for 1 h and restoration for 12 h prevented subsequent damage with 700, 800, and 900 mM (H2O2) on hUC-MSCs. Preconditioning with low-concentration (H2O2) for a short time has a protective effect of preventing damage on hUC-MSCs exposed to high-concentration (H2O2) for a long time, which is dependent on H2O2 concentration and the time interval between preconditioning and damage.