Figure 3.

HA and PPA inhibit cellular senescence in a replicative senescent cell model by passaging mouse ST2 mesenchymal stem cells. (A, B) Senescence‐associated Beta‐Gal activity and p53 mRNA expression in passage 2 and passage 30 ST2 cells in the presence or absence of HA or PPA. PPA (1×) inhibits Beta‐Gal activity (C) in ST2 cells after 2 days (48 hours) and 3 days (72 hours), and inhibits p53 (D) and p21 (E) gene expression. (F) PPA inhibits serum starvation–induced Beta‐Gal activity in ST2 cells. PPA inhibits p53 gene expression after 4 hours of serum starvation (G), and 24‐hour H₂O₂ pretreatment (H). Data are shown as the means ± SE of triplicates of a representative experiment; gene expression was relative to housekeeping gene GAPDH. *p < 0.05 versus control. Beta‐Gal = beta‐galactosidase; HA = hippuric acid; PPA = 3‐(3‐hydroxyphenyl)‐propionic acid.