Fig. 8.

Mesangial cells from INK4a knockout mice are resistant to stress-induced premature senescence. Shown is a flow cytometry cell cycle stage analysis using 4,6-diamidino-2-phenylindole-stained mesangial cells. A: WT. B: INK4a knockout. C: WT 24 h following treatment with 400 μM H₂O₂. D: INK4a knockout following H₂O₂ treatment. E: SA-β-galactosidase staining of WT and INK4a knockout mesangial cells 24 h following H₂O₂ treatment, demonstrating an 85% reduction in senescent cells from knockout mice. *P < 0.0001.