Figure 5.

Adipocyte-specific Ube2i deletion increases energy expenditure and cold intolerance. (A) H/E stained BAT sections from male and female Ube2i^fl/fl and Ube2i^a-KO mice show large unilocular lipid droplets in Ube2i^a-KO mice. Scale bar 100 μm. (B) Relative gene expression by qPCR in BAT from male (left, blue) and female (right, red) Ube2i^a-KO (pink) and Ube2i^fl/fl control (green) mice for brown adipocyte and lipid metabolism genes represented as a heatmap of z-scores (∗p < 0.05, #p < 0.10). Six-month-old Ube2i^fl/fl (gray) and Ube2i^a-KO (blue) male mice were individually housed and monitored in CLAMS home cages for 6 days (n = 4–5/group). (C) Recorded traces of energy expenditure (kcal/hour) with mean values for dark/light periods (kcal/h). (D) Average RER during dark and light periods. (E) Activity was measured by wheel running. (F) Recorded traces of cumulative food intake (kcal) with mean values for dark/light periods (kcal) and (G) total food intake (kcal) per day. (H) Temperature probes were inserted under the skin to monitor intrascapular BAT temperature before (room temperature, RT) and after 2.5 h of cold (4 °C) exposure (n = 3–5/group). Statistical analysis of energy expenditure was performed by ANCOVA with lean body mass as a co-variate and cumulative food intake by standard ANOVA. Data are presented as mean +/− SEM; ∗p < 0.05, #p < 0.10.