Figure 2

The levels of sirt6 proteins decline with celluar senescence.
Celluar senescence was measured using SA-β-gal staining and p16 test. (A) SA-β-gal staining positive cells was found in chondrocytes at passage 10 and 20, but not presented in passage 2. (B) The percentage of SA-β-gal staining positive cells was dramatically increased in passage 20 compared to 10. (C) The expression levels of sirt6 and p16 were measured using western blotting at each passage.