[Profile of P66SHC expression and histone modifications in replicative cell senescence and oxidative-stress induced premature senescence]

To study the profile of P66SHc expression and histone modifications in replicatively senescenct cells and oxidative-stress inducing premature senescenct cells.

HPF cells were continuously cultured and subcultured in vitro to build replicative cellular model. HPF cells were treated with 200 pmol/L H2 O2 four times to build oxidative-stress inducing premature senescenct model. Comparative Q-PCR was utilized to investigate target gene (P66SHC, EP300, HDAC1) expressions respectively in H2O2 treated groups and normal cell groups. Then CHIP-QPCR was conducted to analyze histone modifications of P66SHC between young cells and aging cells.

P66SHC expression was positive correlation with H2O2 doses and population doubling level (PDL) (R = 0.909, P = 0.000; R = 0.743, P = 0.006), while EP300 was negative correlation with H2O2 (R = - 0.922, P = 0.000) and both EP300 and HDAC1 were negative with PDL (R = -0.709, P = 0.010, R = -0.599, P = 0.040). H3 histone modifications were declined in P66SHc gene regulating region. H3-Ac, H3K9-Ac and H3K4-tri-Me were dominant in the upstream region of transcriptional site (-3.0 kb) and alternative promotor (+3.8 kb).

P66SHC, EP300 and HDAC1 probably play a role in cellular replicative senescence and oxidative-stress inducing premature senescence. Besides, histone modification could regulate P66SHC gene expression.