ABSTRACT
BACKGROUND:It is not fuly understood that whetherp53 inhibitor can directly intervene in the viability of bone marrow mesenchymal stem cels and the possible mechanism. OBJECTIVE:To investigate the effect of p53 inhibitor, PFT-α, on the aging process of bone marrow mesenchymal stem cels in late-phase amplification and to discover the key target to delay the replicative senescence of human bone marrow mesenchymal stem cels. METHODS:The expression levels ofp53,p21, andp15 mRNA in human bone marrow mesenchymal stem cels in both early and late-phase amplification were detected by quantitative PCR assay. Then, human bone marrow mesenchymal stem cels in late-phase amplification were respectively treated with 20 μmol/L PFT-α or an equivalent amount of dimethyl sulfoxide for 2 weeks. The positive rate of aging cels was determined by SA-β-Gal staining. The apoptosis was detected by TUNEL staining. Human bone marrow mesenchymal stem cels were treated with 300 μmol/L H2O2 for 30 minutes, and then celular anti-oxidative stress capacity was detected by cel counting kit-8 assay. RESULTS AND CONCLUSION:The quantitative PCR assay showed that the mRNA expression level ofp15, p21 andp53 in human bone marrow mesenchymal stem cels in late-phase amplification was significantly increased (1.45±0.23), (1.51±0.14) and (1.78±0.14) times as much as that in early phase amplification (P < 0.05). The positive rate of aging cels in PFT-α group was significantly lower than that in the dimethyl sulfoxide group[(41±5)%vs. (63±7)%,P < 0.05)]. However, there was no significant difference in apoptosis rate between PFT-α group and dimethyl sulfoxide group. After treatment with H2O2, the absorbance value in the PFT-α group was(1.27±0.13) times as much as that in the dimethyl sulfoxide group (P < 0.001). The above results demonstrate that the activation ofp53 signaling pathway may be an important factor of causing aging of human bone marrow mesenchymal stem cels. Application ofp53 inhibitor PFT-αcan enhance the anti-oxidative stress capacity of human bone marrow mesenchymal stem cels in late phrase amplification.
