Figure 2.

Glucocorticoids Increase Cold-Induced ¹⁸FDG Uptake by BAT

(A) Paired PET/CT scans from a subject demonstrating increased ¹⁸FDG uptake in the supraclavicular BAT (arrows) during the prednisolone phase (left panel).

(B) Paired total ¹⁸FDG uptake by BAT for all six subjects; prednisolone increased uptake by BAT compared with placebo. Data were analyzed using the Wilcoxon signed-rank test.

(C) Plasma cortisol concentrations, shown as mean ± SEM (n = 6), fell following normal diurnal variation in the warm room (p < 0.05 using repeated-measures ANOVA) but did not continue to fall during cooling (t + 120 onward) during the placebo phase (blue line), and were appropriately suppressed by prednisolone (red line).

(D) Prednisolone (red columns) decreased whole-body D2-glucose uptake compared with placebo (blue columns); whole-body D2-glucose uptake was not altered by cold exposure. Data were analyzed using the paired t test. ^∗p < 0.05, prednisolone versus placebo.