Figure 3
Lipid deposition in multilocular cells of brown adipose tissue (BAT) and unilocular cells of white adipose tissue (WAT) is reduced in VGF knockout mice. Representative sections of epididymal WAT (A-C) and interscapular BAT (D-F) from ad lib-fed, age-matched Vgf R +/+ (A, D), +/- (B, E) and -/- (C, F) were stained with H&E. Adipocytes in interscapular BAT and epididymal WAT from -/- mice (C and F) contain less lipid accumulation than the corresponding adipocytes from wild type mice (A and D). Scale bars are 50 μm in length. Morphometric analysis of adipose tissue from Vgf R +/+, +/-, and -/- mice was carried out using MetaMorph, as detailed in Materials and Methods. Lipid area in BAT (panel G), cell area in WAT (panel H), and the distribution of adipocyte perimeters in WAT (panel I), were quantified for each genotype. Note the significant reduction in lipid area in both +/- and -/- BAT (ANOVA, F (2,15) = 73.5, p < 0.0001), significant reduction in adipocyte area in -/- WAT (ANOVA, F (2,15) = 7.6, p = 0.005), and shift in the distribution of cells favoring those with significantly smaller perimeters in -/- and +/- WAT (comparison of mean perimeters in μm; ANOVA, F (2,1167) = 166, p < 0.0001), compared to wild type. Values are mean ± SEM, *p < 0.05, **p = 0.005, ***p < 0.0001 compared to wild type (ANOVA and Bonferroni's posthoc test).