Figure 4.
Vascular endothelial growth factor receptor type 2 (VEGFR2) haploinsufficiency exacerbated kidney dysfunction, fibrosis, and peritubular capillary rarefaction in Klotho-deficient mice. Six mice per line from four different genotypes [wild-type (WT), VEGFR2+/−, kl/kl, and kl/kl;VEGFR2+/−] were euthanized at 6 wk of age. The plasma and kidneys were collected from each mouse for further experiments. A: plasma creatinine (Cr). B: plasma Pi. C: kidney fibrosis assessed with trichrome staining. C, left: representative microscopic images. Scale bar = 200 µm. C, right: quantitative analysis of fibrotic scores on trichrome-stained kidney sections with ImageJ software. D: immunoblot analysis for endothelial marker (CD31), Klotho, α-smooth muscle actin (α-SMA), connective tissue growth factor (CTGF), and β-actin in total kidney lysates. D, left: representative blots. D, right: quantitative analysis of all immunoblots from the four groups. A–D: quantitative data are expressed with scatterplots of individual data points (open circles indicate male mice and pink circles indicate female mice) and means ± SD (bars and errors) of all mice from each group. Statistical significance was evaluated by two-way ANOVA followed by a Student–Newman–Keuls test, and significance was accepted when *P < 0.05 and **P < 0.01 between two groups. The sample number in each group is presented in parentheses underneath each corresponding bar. VR2, VEGFR2.