Fig. 3.

Heterozygous Wt1 knockout mice fed with HFD have lower epididymal WAT to body weight ratios. Wild-type and heterozygous Wt1 knockout mice (n = 40 total) were kept on either chow diet (10% of kJ from fat) or HFD (60% of kJ from fat) for 11 weeks. (a) Epididymal WAT (epiWAT) weight to body weight ratios. Bars indicate means ± SEM, n = 10, each. *p < 0.05 between wild-type and Wt1 mutant animals (Student’s t test). Note that, for better data visualisation, statistical significance between mice receiving chow diet and HFD is not indicated. (b) Representative H&E staining of epiWAT of a wild-type and heterozygous Wt1 knockout mouse fed with either chow or HFD. Scale bars, 100 μm. (c) Frequency distribution of adipocyte areas in epididymal WAT of wild-type and heterozygous Wt1 knockout mice receiving either chow diet or HFD. Measurements were performed with tissue sections from n = 40 animals analysing more than 2500 cells per group. Statistical differences between mice of identical genotype receiving HFD vs chow diet are indicated by asterisks (*p < 0.05, **p < 0.01, ***p < 0.001, ANOVA with Tukey post hoc test). ^†p < 0.05, statistical differences between wild-type and heterozygous Wt1 knockout mice (ANOVA with Tukey post hoc test). Note that the adipocyte areas were not significantly different between wild-type and heterozygous Wt1 knockout mice except for the size range 2001–4000 μm². In this particular range, Wt1 knockout mice fed with chow diet had significantly smaller adipocytes in their epididymal WAT than wild-type mice. (d) Relative mRNA levels of inflammation-related genes in epididymal WAT of normal and Wt1 mutant mice. Bars represent means ± SEM, n = 10 in each group. *p < 0.05, **p < 0.01 and ***p < 0.001 as shown, ANOVA with Tukey post hoc test. (e) Relative Wt1 mRNA levels in epididymal WAT of wild-type mice receiving either chow diet or HFD. Transcripts were measured by RT-qPCR and normalised to Actb mRNA. Bars indicate means ± SEM, n = 10. (f) Relative transcript levels of genes involved in fatty acid and glucose homeostasis in epididymal WAT of wild-type and heterozygous Wt1 knockout mice receiving either normal diet or HFD. Bars show means ± SEM, n = 10 in each group. *p < 0.05 and **p < 0.01 between mice of the same genotype receiving HFD vs chow diet, ANOVA with Tukey post hoc test