Sublethal Oxidative Stress Induces the Premature Senescence of Human Mesenchymal Stem Cells Derived from Endometrium
Figure 4
Induction of the premature senescence in hMESCs under oxidative stress leads to the permanent arrest of cell cycle and irreversible loss of proliferative potential. Cell treatment was done as described in Figure 2. (a) Growth curve of both H2O2-treated and untreated cells. Cell number was determined daily after cell exposure to H2O2 by FACS analysis (M ± SEM, , , ). (b) H2O2-treated cells were either cultured for 5 days or were reseeded in 2 days and additionally cultured for 3 days. Flow cytometry analysis of cell cycle phase distribution: the percentage of cells in the G0/G1, S, and G2/M phases (upper panel) (); visualization of phase distribution based on light-scattering analysis (lower panel); SS: side scattering, FL3: PI fluorescence. (c) The expression levels of p21 protein. Representative results of the three experiments are shown in the figure. (d) The levels of p21 mRNA expression. GAPDH and -actin were used as loading controls. (e) The nuclear localization of Ki67 was tested in control or H2O2-treated cells by immunofluorescence and DAPI staining. Representative photomicrographs of the staining are shown. Images were taken at magnification 100x. Control (Ctr): untreated cells.
