Effects of Sirt3 on cisplatin-induced tubular apoptosis. (A) Kidneys from WT and Sirt3KO mice treated with vehicle or cisplatin were evaluated for tubular apoptosis by a TUNEL assay. The bar graph shows the number of TUNEL-positive cells in WT and Sirt3KO mice treated with vehicle or cisplatin. A total of 10 randomly selected, nonoverlapping fields were quantified (n=10 in each group; magnification, ×400). Data are expressed as the mean ± standard deviation. Scale bar, 50 µm. (B) Representative western blotting for caspase-3 and cleaved caspase-3 from the kidneys of WT and Sirt3KO mice treated with vehicle or cisplatin. Data from densitometric analysis were presented as the relative ratio of each protein to β-actin. The relative ratio measured in kidneys from WT mice treated with vehicle is arbitrarily presented as 1. Data are expressed as the4 mean ± standard deviation. **P<0.01 vs. Veh; ##P<0.01 vs. WT cisplatin. Veh, vehicle; WT, wild type; Sirt3, Sirtuin 3; KO, knockout; TUNEL, terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling.