| Pathway description: |
In agreement with the real-time reverse transcription-polymerase chain reaction (RT-PCR) data, Western blot analysis confirmed that, after exposure to H2O2, UC-MSCs on TCPS showed the highest expression of p16INK4α which was 2.7-fold of that on DECM . The levels of SIRT1 decreased in H2O2-treated cells, but DECM preserved the expression of SIRT1 .The levels of p53 showed no significant difference but, as its transcriptional target, p21 was significantly upregulated in TCPS-cultured cells .To determine the roles of p38 and Erk1/2 in H2O2-induced premature senescence, we measured the phosphorylated levels of p38 and Erk1/2. We found that treatment with H2O2 significantly enhanced phosphorylation of p38 by 6.1-fold compared with the untreated cells on TCPS, whereas DECM attenuated p-p38 by 67.8% compared with H2O2-treated cells on TCPS. However, we found that the total p38 protein expression did not vary in all the groups. The differences of phosphorylated and total levels of Erk1/2 were insignificant. Before treating with H2O2, the levels of p-Erk1/2 were higher in DECM-cultured cells than in the TCPS-cultured cells (p = 0.28) and, after exposure to H2O2, the levels of p-Erk1/2 showed an opposite tendency . |