Figure 5.

Irregularly shaped nuclei in electron micrographs are associated with apoptotic podocyte death in aging CD^pdKO mice. (A) Immunofluorescence staining showed that WT1-positive dots (green) in glomeruli from CD^pdKO mice were decreased at 15 months of age. (B) WT1-positive cells in CD^pdKO mice were significantly decreased compared with those in their CD^Ctrl littermates at 3, 12, and 20 months of age. Analysis was performed on 50–60 glomeruli of each mouse. (C) Immunohistochemical staining with anticleaved caspase-8 showed cleaved caspase-8–positive podocytes of 12-month-old CD^pdKO mice. (D) Quantification of the number of cleaved caspse-8–positive dots in 12-month-old mice showed a significantly higher rate in CD^pdKO mice than in their CD^Ctrl littermates; ≥350 glomeruli of each mouse were analyzed. (E) Immunofluorescence staining showed that cleaved caspase-3–positive dots (green) in the glomeruli from CD^pdKO mice were increased at 12 months of age (red, synaptopodin; green, cleaved caspase-3; 4′,6-diamidine-2-phenylindole staining). (F) Quantification of the number of cleaved caspase-3 dots in 12- and 20-month-old mice showed a significantly higher percentage ratio in CD^pdKO mice than in their CD^Ctrl littermates; ≥200 glomeruli of each mouse were analyzed. (G) TUNEL staining showed that TUNEL-positive dots (arrow) in the glomeruli from CD^pdKO mice were increased at 20 months of age. (H) Quantification of the number of TUNEL-positive dots in 20-month-old mice showed a significantly higher rate in CD^pdKO mice than in their CD^Ctrl littermates; ≥200 glomeruli of each mouse were analyzed. The data are the means±SEMs. *P<0.05; **P<0.01 two–tailed Mann–Whitney U test; ***P<0.001 by two–tailed Mann–Whitney U test.