Fig. 1.

Identification of fisetin as a putative senolytic. (A) Passage 5 Ercc1^−/− MEFs were treated with a panel of flavonoid compounds at a dose of 5 μM and the viability of senescent cells (SA-β-gal⁺ cells detected by C₁₂FDG staining; red bars) and total cells (black bars) measured using an IN Cell Analyzer 6000. The number of viable cells is calculated relative to cells treated with vehicle only (DMSO). n = 3 independent experiments, one-way ANOVA. (B) Quantitation of the total number of viable Ercc1^−/− MEFs and viable senescent Ercc1^−/− MEFs after treating mixed cultures of proliferating and senescent cells with various doses of fisetin from two biological replicates conducted in triplicate. Two-tailed unpaired Student's t-test. (C) Early passage IMR90 cells were treated for 24 h with 20 μM etoposide. Two days after etoposide removal, ~70% of the cells were SA-β-gal⁺. Cells were treated for 48 h with different concentrations of fisetin (1–15 μM) and the percentage of SA-β-gal⁺ cells was determined using C₁₂FDG, as described above. Graphed are the relative number of viable cells compared to cultures treated with vehicle only (DMSO). All samples were analyzed in duplicate with 3–5 fields per well and reported as the mean ± S.D. Two-tailed unpaired Student's t-test. Plotted is the mean ± SEM. *p < .05, **p < .01, ***p < .001, ****p < .0001.