Figure 3. Brown adipose tissue morphology and aging. Tissues of young (27–31 weeks old; white circles) and middle-aged (67–71 weeks old; black circles) female APOE*3-Leiden.CETP mice were collected at Zeitgeber Time 0 and 12 (n = 7–8 mice/group/time point). (A) interscapular brown adipose tissue (iBAT) and (B) subscapular BAT (sBAT) were weighed, and (C, D) expressed as percentage of body weight (n = 5–8 mice/group/time point). (E) Lipid content of sBAT was quantified and representative pictures are shown (n = 5–8/group/time point). Bar graphs represent means ± SD. *p < 0.05; **p < 0.01, according to two-way ANOVA and following Tukey’s multiple-comparison test.