Figure 4
VGF ablation affects UCP1 & UCP2 protein expression, mitochondrial morphology, and mitochondrial number in BAT. Representative western blots of UCP1, UCP2, and GAPDH protein levels in BAT from Vgf R +/+, +/-, and -/- mice (panel A), and densitometric quantification by NIH image (panel B). Comparable results were found in at least three additional experiments. Ablation of VGF significantly increased UCP1 and UCP2 levels in BAT from Vgf R -/- but not Vgf R +/- mice compared to wild type +/+ mice [n = 5 mice per group, mean ± SEM, F (2,12) = 4.35 (UCP1), F (2,12) = 3.33 (UCP2), *p < 0.05, ANOVA and Dunnett's posthoc test]. Representative electron microscope photomicrographs of BAT from Vgf R -/- (panels C-E) and +/+ mice (panels F-H) are shown. The part of the image that is boxed in red is shown at higher magnification in the panel to its immediate right. Scale bars are 5 μm (panels C and F), 2.5 μm (panels D and G), and 1.25 μm (panels E and H). Note that mitochondria are smaller and more numerous in Vgf R -/- in comparison to +/+ BAT (compare panels E and H), which is quantified in panels I and J. In panel K, the number of cristae per μm2 of mitochondrial area was quantified in Vgf R -/- and +/+ BAT. Values are mean ± SEM; ***p = 0.0002 (panel E), **p = 0.001 (panel F), ***p < 0.0001 (panel G) (Student's t-test).