FVL protects against podocyte loss. (A-B) Podocyte number in glomeruli as determined by WT-1 immunohistochemical staining. Podocyte frequency was reduced in the glomeruli of diabetic wild-type mice (FVwt, arrows), but not in diabetic heterozygous (FVLr/q, arrows) or diabetic homozygous (FVLq/q, arrows) FVL mice. WT-1–positive cells detected by HRP-DAB reaction (brown) or hematoxylin counterstain (blue); n ≥ 7 for each group. (C) Bar graph (top, data normalized for podocyte numbers) and representative immunoblot (bottom) showing GLEPP1 expression in renal cortex tissue samples. GLEPP1 expression was reduced in diabetic wild-type, but not in diabetic FVL-positive mice. Actin immunoblot is shown as loading control (n ≥ 7 for each group). (D) Bar graph (top) and representative immunoblots of immunoprecipitates (bottom) showing nephrin tyrosine phosphorylation in renal cortex tissue samples. Nephrin tyrosine phosphorylation (normalized to total nephrin) is reduced in diabetic wild-type but not in diabetic FVL-positive mice. Bar graphs summarizing the results (n ≥ 7 for each group). Scale bar indicates 15 μm (A). C indicates nondiabetic, control mice (white bars); DM, diabetic mice (black bars); means ± SEM are shown; *P < .05; **P < .01 (ANOVA).