Quercetin protects against cholesterol-induced apoptosis of Min6 cells. The activities of (A) caspase-3 and (B) caspase-9 were measured after 6 h incubation with 320 µM cholesterol and/or 10–100 µM QUE. Cholesterol was also incubated with specific caspase inhibitors, DEVD-CHO and LEHD-CHO, respectively. (C) Cytochrome c release was quantified in media from cells treated for 6 h with 320 µM cholesterol and/or 10–100 µM QUE. (D) TUNEL staining after 6 h incubation with 320 µM cholesterol and/or 50 µM QUE. (E) Quantification of DNA fragmentation. Values are expressed as mean ± SEM, from three independent culture preparations, each treatment performed in triplicate. All one-way ANOVA (p values specified in results), symbols indicate Bonferroni post-test significances #relative to control and *to cholesterol-treated Min6 cells.